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HIV-like viruses in non-human primates have existed much longer than previously thought

HIV-like viruses in non-human primates have existed much longer than previously thought | Amazing Science | Scoop.it

Viruses similar to those that cause AIDS in humans were present in non-human primates in Africa at least 5 million years ago and perhaps up to 12 million years ago, according to study by scientists at Fred Hutchinson Cancer Research Center. Until now, researchers have hypothesized that such viruses originated much more recently.

 

HIV-1, the virus responsible for AIDS, infiltrated the human population in the early 20th century following multiple transmissions of a similar chimpanzee virus known as SIVcpz. Previous work to determine the age of HIV-like viruses, called lentiviruses, by comparing their genetic blueprints has calculated their origin to be tens of thousands of years ago.

 

However, other researchers have suspected this time frame to be much too recent. Michael Emerman, Ph.D., a virologist and member of the Human Biology Division at Fred Hutchinson Cancer Research Center, and Alex Compton, a graduate student in the Emerman Lab, describe the use of a technique to estimate the extent to which primates and lentiviruses have coexisted by tracking the changes in a host immunity gene called APOBEC3G that were induced by ancient viral challenges.

 

They report that this host immunity factor is evolving in tandem with a viral gene that defends the virus against APOBEC3G, which allowed them to determine the minimum age for the association between primates and lentiviruses to be around 5 or 6 million years ago, and possibly up to 12 million years ago.

 

These findings suggest that HIV-like infections in primates are much older than previously thought, and they have driven selective changes in antiviral genes that have incited an evolutionary arms race that continues to this day. The study also confirms that viruses similar to HIV that are present in various monkey species today are the descendants of ancient pathogens in primates that have shaped how the immune system fights infections.

 

"More than 40 non-human primate species in sub-Saharan Africa are infected with strains of HIV-related viruses," Emerman said. "Since some of these viruses may have the potential to infect humans as well, it is important to know their origins."

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20,000+ FREE Online Science and Technology Lectures from Top Universities

20,000+ FREE Online Science and Technology Lectures from Top Universities | Amazing Science | Scoop.it

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Siegfried Holle's curator insight, July 4, 2014 8:45 AM

Your knowledge is your strength and power 

Saberes Sin Fronteras Ong's curator insight, November 30, 2014 5:33 PM

Acceso gratuito a documentos de las mejores universidades del mundo

♥ princess leia ♥'s curator insight, December 28, 2014 11:58 AM

WoW  .. Expand  your mind!! It has room to grow!!! 

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DNA 'cage' holding a payload of drugs set to begin clinical trial soon

DNA 'cage' holding a payload of drugs set to begin clinical trial soon | Amazing Science | Scoop.it

Ido Bachelet, who was previously at Harvard’s Wyss Institute in Boston, Massachusetts and Israel’s Bar-Ilan University, intends to treat a patient who has been given six months to live. The patient is set to receive an injection of DNA nanocages designed to interact with and destroy leukemia cells without damaging healthy tissue. Speaking in December, he said: ‘Judging from what we saw in our tests, within a month that person is going to recover.


DNA nanocages can be programmed to independently recognize target cells and deliver payloads, such as cancer drugs, to these cells. 

George Church, who is involved in the research at the Wyss Institute explained the idea of the microscopic robots is to make a ‘cage’ that protects a fragile or toxic payload and ‘only releases it at the right moment.’


These nanostructures are built upon a single strand of DNA which is combined with short synthetic strands of DNA designed by the experts.  When mixed together, they self-assemble into a desired shape, which in this case looks a little like a barrel.


Dr Bachelet said: 'The nanorobot we designed actually looks like an open-ended barrel, or clamshell that has two halves linked together by flexible DNA hinges and the entire structure is held shut by latches that are DNA double helixes.’


A complementary piece of DNA is attached to a payload, which enables it to bind to the inside of the biological barrel. The double helixes stay closed until specific molecules or proteins on the surface of cancer cells act as a 'key' to open the ‘barrel’ so the payload can be deployed.


'The nanorobot is capable of recognizing a small population of target cells within a large healthy population,’ Dr Bachelet continued.

‘While all cells share the same drug target that we want to attack, only those target cells that express the proper set of keys open the nanorobot and therefore only they will be attacked by the nanorobot and by the drug.’


The team has tested its technique in animals as well as cell cultures and said the ‘nanorobot attacked these [targets] with almost zero collateral damage.’ The method has many advantages over invasive surgery and blasts of drugs, which can be ‘as painful and damaging to the body as the disease itself,’ the team added.

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Mammoth genome sequence completed

Mammoth genome sequence completed | Amazing Science | Scoop.it

An international team of scientists has sequenced the complete genome of the woolly mammoth. A US team is already attempting to study the animals' characteristics by inserting mammoth genes into elephant stem cells. They want to find out what made the mammoths different from their modern relatives and how their adaptations helped them survive the ice ages.


The new genome study has been published in the journal Current BiologyDr Love Dalén, at the Swedish Museum of Natural History in Stockholm, told BBC News that the first ever publication of the full DNA sequence of the mammoth could help those trying to bring the creature back to life. "It would be a lot of fun (in principle) to see a living mammoth, to see how it behaves and how it moves," he said.


But he would rather his research was not used to this end. "It seems to me that trying this out might lead to suffering for female elephants and that would not be ethically justifiable."


Dr Dalén and the international group of researchers he is collaborating with are not attempting to resurrect the mammoth. But the Long Now Foundation, an organisation based in San Francisco, claims that it is. Now, with the publication of the complete mammoth genome, it could be a step closer to achieving its aim.


On its website, the foundation says its ultimate goal is "to produce new mammoths that are capable of repopulating the vast tracts of tundra and boreal forest in Eurasia and North America. "The goal is not to make perfect copies of extinct woolly mammoths, but to focus on the mammoth adaptations needed for Asian elephants to live in the cold climate of the tundra.

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Scientists use nanoscale building blocks and DNA 'glue' to shape 3-D superlattices

Scientists use nanoscale building blocks and DNA 'glue' to shape 3-D superlattices | Amazing Science | Scoop.it
aking child's play with building blocks to a whole new level-the nanometer scale-scientists at the U.S. Department of Energy's (DOE) Brookhaven National Laboratory have constructed 3D "superlattice" multicomponent nanoparticle arrays where the arrangement of particles is driven by the shape of the tiny building blocks. The method uses linker molecules made of complementary strands of DNA to overcome the blocks' tendency to pack together in a way that would separate differently shaped components. The results, published in Nature Communications, are an important step on the path toward designing predictable composite materials for applications in catalysis, other energy technologies, and medicine. "If we want to take advantage of the promising properties of nanoparticles, we need to be able to reliably incorporate them into larger-scale composite materials for real-world applications," explained Brookhaven physicist Oleg Gang, who led the research at Brookhaven's Center for Functional Nanomaterials (CFN), a DOE Office of Science User Facility.

"Our work describes a new way to fabricate structured composite materials using directional bindings of shaped particles for predictable assembly," said Fang Lu, the lead author of the publication.

The research builds on the team's experience linking nanoparticles together using strands of synthetic DNA. Like the molecule that carries the genetic code of living things, these synthetic strands have complementary bases known by the genetic code letters G, C, T, and A, which bind to one another in only one way (G to C; T to A). Gang has previously used complementary DNA tethers attached to nanoparticles to guide the assembly of a range of arrays and structures. The new work explores particle shape as a means of controlling the directionality of these interactions to achieve long-range order in large-scale assemblies and clusters.

Spherical particles, Gang explained, normally pack together to minimize free volume. DNA linkers-using complementary strands to attract particles, or non-complementary strands to keep particles apart-can alter that packing to some degree to achieve different arrangements. For example, scientists have experimented with placing complementary linker strands in strategic locations on the spheres to get the particles to line up and bind in a particular way. But it's not so easy to make nanospheres with precisely placed linker strands.

"We explored an alternate idea: the introduction of shaped nanoscale 'blocks' decorated with DNA tethers on each facet to control the directional binding of spheres with complementary DNA tethers," Gang said.
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Technology Trends - Singularity Blog: Most Anticipated New Technologies for 2015/2016

Technology Trends - Singularity Blog: Most Anticipated New Technologies for 2015/2016 | Amazing Science | Scoop.it
Future timeline, a timeline of humanity's future, based on current trends, long-term environmental changes, advances in technology such as Moore's Law, the latest medical advances, and the evolving geopolitical landscape.


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Ursula Sola de Hinestrosa's curator insight, April 24, 4:50 PM

Nuevas tecnologias

AugusII's curator insight, April 25, 6:15 PM

Being up to date a must -  Learning on trends useful.

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The Current State of Machine Intelligence

The Current State of Machine Intelligence | Amazing Science | Scoop.it

A few years ago, investors and startups were chasing “big data”. Now we’re seeing a similar explosion of companies calling themselves artificial intelligence, machine learning, or collectively “machine intelligence”. The Bloomberg Beta fund, which is focused on the future of work, has been investing in these approaches.


Computers are learning to think, read, and write. They’re also picking up human sensory function, with the ability to see and hear (arguably to touch, taste, and smell, though those have been of a lesser focus).


Machine intelligence technologies cut across a vast array of problem types (from classification and clustering to natural language processing and computer vision) and methods (from support vector machines to deep belief networks). All of these technologies are reflected on this landscape.


What this landscape doesn’t include, however important, is “big data” technologies. Some have used this term interchangeably with machine learning and artificial intelligence, but I want to focus on the intelligence methods rather than data, storage, and computation pieces of the puzzle for this landscape (though of course data technologies enable machine intelligence).


We’ve seen a few great articles recently outlining why machine intelligence is experiencing a resurgence, documenting the enabling factors of this resurgence. Kevin Kelly, for example chalks it up to cheap parallel computing, large datasets, and better algorithms.


Machine intelligence is enabling applications we already expect like automated assistants (Siri), adorable robots (Jibo), and identifying people in images (like the highly effective but unfortunately named DeepFace). However, it’s also doing the unexpected: protecting children from sex trafficking, reducing the chemical content in the lettuce we eat, helping us buy shoes online that fit our feet precisely, anddestroying 80's classic video games.


Big companies have a disproportionate advantage, especially those that build consumer products. The giants in search (Google, Baidu), social networks (Facebook, LinkedIn, Pinterest), content (Netflix, Yahoo!), mobile (Apple) and e-commerce (Amazon) are in an incredible position. They have massive datasets and constant consumer interactions that enable tight feedback loops for their algorithms (and these factors combine to create powerful network effects) — and they have the most to gain from the low hanging fruit that machine intelligence bears.

Best-in-class personalization and recommendation algorithms have enabled these companies’ success (it’s both impressive and disconcerting that Facebook recommends you add the person you had a crush on in college and Netflix tees up that perfect guilty pleasure sitcom).

Now they are all competing in a new battlefield: the move to mobile. Winning mobile will require lots of machine intelligence: state of the art natural language interfaces (like Apple’s Siri), visual search (like Amazon’s “FireFly”), and dynamic question answering technology that tells you the answer instead of providing a menu of links (all of the search companies are wrestling with this).Large enterprise companies (IBM and Microsoft) have also made incredible strides in the field, though they don’t have the same human-facing requirements so are focusing their attention more on knowledge representation tasks on large industry datasets, like IBM Watson’s application to assist doctors with diagnoses.
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John Vollenbroek's curator insight, April 25, 2:53 AM

I like this overview

pbernardon's curator insight, April 26, 2:33 AM

Une infographie et une cartographie claire et très intéressante sur l'intelligence artificielle et les usages induits que les organisations vont devoir s'approprier.

 

#bigdata 

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Two huge magma chambers sit beneath Yellowstone National Park

Two huge magma chambers sit beneath Yellowstone National Park | Amazing Science | Scoop.it
Underneath the bubbling geysers and hot springs of Yellowstone National Park in Wyoming sits a volcanic hot spot that has driven some of the largest eruptions on Earth. Geoscientists have now completely imaged the subterranean plumbing system and have found not just one, but two magma chambers underneath the giant volcano.

“The main new thing is we unveil a deeper and bigger magma reservoir in the lower crust,” says study author Hsin-Hua Huang, a seismologist at the University of Utah in Salt Lake City.

Scientists had already known about a plume, which brings molten rock up from deep in the mantle to a region about 60 kilometers below the surface. And they had also imaged a shallow magma chamber about 10 kilometers below the surface, containing about 10,000 cubic kilometers of molten material. But now they have found a deeper one, 4.5 times larger, that sits between 20 and 50 kilometers below the surface. “They found the missing link between the mantle plume and the shallow magma chamber,” says Peter Cervelli, a geophysicist in Anchorage, Alaska, who works at the U.S. Geological Survey’s Yellowstone Volcano Observatory.

The discovery does not, on its own, increase the chance of an eruption, which is driven by an emptying of the shallow chamber. The last major eruption was 640,000 years ago, and today the threat of earthquakes is far more likely. But the deeper chamber does mean that the shallow chamber can be replenished again and again. “Knowing that you have this additional reservoir tells you you could have a much bigger volume erupt over a relatively short time scale,” says co-author Victor Tsai, a geophysicist at the California Institute of Technology in Pasadena. The discovery, reported online today in Science, also confirms a long-suspected model for some volcanoes, in which a deep chamber of melted basalt, a dense iron- and magnesium-rich rock, feeds a shallower chamber containing a melted, lighter silicon-rich rock called a rhyolite.

The researchers used seismometers to measure the noise of earthquakes in order to take a sort of sonogram of Earth’s crust. When earthquakes pass through liquid material, seismic waves slow down. The team interprets these low-velocity regions as magma chambers (although these chambers are still mostly solid rock and contain only a small fraction of liquid melt). Distant earthquakes are useful for imaging deep structures, like the mantle plume, and local earthquakes can help to see the shallow chamber. Huang says his study is the first time that both types of data were combined so that the middle depths, and the deeper chamber, could be seen. His team used 11 seismometers from the EarthScope USArray to listen for the deep earthquakes and 69 seismometers from several local seismic networks to gather data from shallower earthquakes.
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Lipid-nanoparticle-encapsulated siRNAs cure monkeys infected with West African Ebola strain

Lipid-nanoparticle-encapsulated siRNAs cure monkeys infected with West African Ebola strain | Amazing Science | Scoop.it
An experimental drug has cured monkeys infected with the strain of the Ebola virus present in West Africa, US-based scientists say.


An experimental drug has cured monkeys infected with the Ebola virus, US-based scientists have said. The treatment, known as TKM-Ebola-Guinea, targets the Makona strain of the virus, which caused the current deadly outbreak in West Africa. All three monkeys receiving the treatment were healthy when the trial ended after 28 days; three untreated monkeys died within nine days. Scientists cautioned that the drug's efficacy has not been proven in humans. At present, there are no treatments or vaccines for Ebola that have been proven to work in humans.


University of Texas scientist Thomas Geisbert, who was the senior author of the study published in the journal Nature, said: "This is the first study to show post-exposure protection... against the new Makona outbreak strain of Ebola-Zaire virus." Results from human trials with the drug are expected in the second half of this year.


The current outbreak of Ebola virus in West Africa is unprecedented, causing more cases and fatalities than all previous outbreaks combined, and has yet to be controlled1. Several post-exposure interventions have been employed under compassionate use to treat patients repatriated to Europe and the United States2. However, the in vivo efficacy of these interventions against the new outbreak strain of Ebola virus is unknown.


In the current study, the scientists show that lipid-nanoparticle-encapsulated short interfering RNAs (siRNAs) rapidly adapted to target the Makona outbreak strain of Ebola virus are able to protect 100% of rhesus monkeys against lethal challenge when treatment was initiated at 3 days after exposure while animals were viremic and clinically ill.


Although all infected animals showed evidence of advanced disease including abnormal hematology, blood chemistry and coagulopathy, siRNA-treated animals had milder clinical features and fully recovered, while the untreated control animals succumbed to the disease. These results represent the first successful demonstration of therapeutic anti-Ebola virus efficacy against the new outbreak strain in non-human primates and highlight the rapid development of lipid-nanoparticle-delivered siRNA as a countermeasure against this highly lethal human disease.

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Ultra-high-resolution nondestructive 3D imaging of biological cells with picosecond ultrasound

Ultra-high-resolution nondestructive 3D imaging of biological cells with picosecond ultrasound | Amazing Science | Scoop.it

A team of researchers in Japan and Thailand reports the first known nondestructive 3-D scan of a single biological cell using a revised form of “picosecond* ultrasound.” This new technique can achieve micrometer (millionth of a meter) resolution of live single cells, imaging their interiors in slices separated by 150 nanometers (.15 micrometer), in contrast to the typical 0.5-millimeter (500 micrometers) spatial resolution of a standard medical MRI scan. The work is a proof-of-principle that could open the door to new ways of studying the physical properties of living cells by imaging them non-destructively in vivo, the researchers say.


The team accomplished the imaging by first placing a cell in solution on a titanium-coated sapphire substrate and then scanning with a point source of high-frequency sound generated by using a beam of focused ultrashort laser pulses over the titanium film. This was followed by focusing another beam of laser pulses on the same point to pick up tiny changes in optical reflectance caused by the sound traveling through the cell tissue.


“By scanning both beams together, we’re able to build up an acoustic image of the cell that represents one slice of it,” explained co-author Professor Oliver B. Wright, who teaches in the Division of Applied Physics, Faculty of Engineering at Hokkaido University. “We can view a selected slice of the cell at a given depth by changing the timing between the two beams of laser pulses.”


“The time required for 3-D imaging [with conventional acoustic microscopes] probably remains too long to be practical,” Wright said. “Building up a 3-D acoustic image, in principle, allows you to see the 3-D relative positions of cell organelles without killing the cell.


“By using an ultraviolet-pulsed laser, we could improve the lateral resolution by about a factor of three — and greatly improve the image quality. And, switching to a diamond substrate instead of sapphire would allow better heat conduction away from the probed area, which, in turn, would enable us to increase the laser power and image quality.”

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New WiFi system uses LED lights to boost bandwidth tenfold

New WiFi system uses LED lights to boost bandwidth tenfold | Amazing Science | Scoop.it

Researchers at Oregon State University have invented a new technology called WiFiFO (WiFi Free space Optic) that can increase the bandwidth of WiFi systems by 10 times, using optical transmission via LED lights. The technology could be integrated with existing WiFi systems to reduce bandwidth problems in crowded locations, such as airport terminals or coffee shops, and in homes where several people have multiple WiFi devices.


Experts say that recent advances in LED technology have made it possible to modulate the LED light more rapidly, opening the possibility of using light for wireless transmission in a “free space” optical communication system. “In addition to improving the experience for users, the two big advantages of this system are that it uses inexpensive components, and it integrates with existing WiFi systems,” said Thinh Nguyen, an OSU associate professor of electrical and computer engineering. Nguyen worked with Alan Wang, an assistant professor of electrical and computer engineering, to build the first prototype.


“I believe the WiFO system could be easily transformed into a marketable product, and we are currently looking for a company that is interested in further developing and licensing the technology,” Nguyen said. 


The system can potentially send data at up to 100 megabits per second. Although some current WiFi systems have similar bandwidth, it has to be divided by the number of devices, so each user might be receiving just 5 to 10 megabits per second, whereas the hybrid system could deliver 50–100 megabits to each user. In a home where telephones, tablets, computers, gaming systems, and televisions may all be connected to the Internet, increased bandwidth would eliminate problems like video streaming that stalls and buffers (think Netflix).


The receivers are small photodiodes that cost less than a dollar each and could be connected through a USB port for current systems, or incorporated into the next generation of laptops, tablets, and smartphones. A provisional patent has been secured on the technology, and a paper was published in the 17th ACM International Conference on Modeling, Analysis and Simulation of Wireless and Mobile Systems. 


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Glassy Butterflies: Low-reflection Wings Make Butterflies Nearly Invisible

Glassy Butterflies: Low-reflection Wings Make Butterflies Nearly Invisible | Amazing Science | Scoop.it

The effect is known from the smart phone: Sun is reflected by the display and hardly anything can be seen. In contrast to this, the glasswing butterfly hardly reflects any light in spite of its transparent wings. As a result, it is difficult for predatory birds to track the butterfly during the flight. Researchers of KIT under the direction of Hendrik Hölscher found that irregular nanostructures on the surface of the butterfly wing cause the low reflection. In theoretical experiments, they succeeded in reproducing the effect that opens up fascinating application options, e.g. for displays of mobile phones or laptops.


Transparent materials such as glass, always reflect part of the incident light. Some animals with transparent surfaces, such as the moth with its eyes, succeed in keeping the reflections small, but only when the view angle is vertical to the surface. The wings of the glasswing butterfly that lives mainly in Central America, however, also have a very low reflection when looking onto them under higher angles. Depending on the view angle, specular reflection varies between two and five percent. For comparison: As a function of the view angle, a flat glass plane reflects between eight and 100 percent, i.e. reflection exceeds that of the butterfly wing by several factors. Interestingly, the butterfly wing does not only exhibit a low reflection of the light spectrum visible to humans, but also suppresses the infrared and ultraviolet radiation that can be perceived by animals. This is important to the survival of the butterfly.


For research into this so far unstudied phenomenon, the scientists examined glasswings by scanning electron microscopy. Earlier studies revealed that regular pillar-like nanostructures are responsible for the low reflections of other animals. The scientists now also found nanopillars on the butterfly wings. In contrast to previous findings, however, they are arranged irregularly and feature a random height. Typical height of the pillars varies between 400 and 600 nanometers, the distance of the pillars ranges between 100 and 140 nanometers. This corresponds to about one thousandth of a human hair.


In simulations, the researchers mathematically modeled this irregularity of the nanopillars in height and arrangement. They found that the calculated reflected amount of light exactly corresponds to the observed amount at variable view angles. In this way, they proved that the low reflection at variable view angles is caused by this irregularity of the nanopillars. Hölscher’s doctoral student Radwanul Hasan Siddique, who discovered this effect, considers the glasswing butterfly a fascinating animal: “Not only optically with its transparent wings, but also scientifically. In contrast to other natural phenomena, where regularity is of top priority, the glasswing butterfly uses an apparent chaos to reach effects that are also fascinating for us humans.”


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Warm bodied fishes found able to swim farther and faster than cold bodied fish

Warm bodied fishes found able to swim farther and faster than cold bodied fish | Amazing Science | Scoop.it

A team of researchers with members from Japan, the U.S. and the U.K. has found that some warm bodied sharks and tunas are able to swim more than twice as fast non-warm bodied fish and they are also able to swim farther. In their paper published in the journal Proceedings of the National Academy of Sciences, the team describes how they used existing data along with new data they obtained by attaching sensors to several sharks in different locations around the world, to better understand endothermy in fishes and what their studies revealed.

Fish are generally thought of as cold-blooded creatures—their internal temperature matches the temperature of the water around them. But some species have been found to have internal temperatures higher than the water around them—sometimes as much as 20°C higher. Common sense suggests that a higher internal temperature must come at some cost, which of course would be the need to eat more food than cold bloodied sea creatures. The natural question then is, what benefit would a fish or shark receive as a result of having warmer insides? That was what the researchers with this new effort sought to learn.


To find out, they scoured the current literature and then conducted some field studies of their own, attaching sensors to some sharks that are known to be warm bodied. In analyzing the data from their work, they found that warm bodied sharks were able to swim on average 2.7 times as speedily as similar sized sharks that were not warm bodied—they also found that they were able to swim farther.


The researchers suggest warmer "red" muscle endothermy offers more power per pound for the sharks and other warm bodied fish, allowing for speedier acceleration and more staying power. In their experiments, they found that that the warm bodied sharks were able to swim long distances in a reasonably short amount of time, which they note, would allow them to take advantage of seasonal changes in different locales. It also might be a positive attribute as the seas warm. They suggest their study and results offer a plausible explanation for the evolution of endothermy in fish.

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Earth-Size Event Horizon Telescope Will Explore Black Hole In Center Of Our Galaxy

Earth-Size Event Horizon Telescope Will Explore Black Hole In Center Of Our Galaxy | Amazing Science | Scoop.it

Looking into the galactic center is hard. Too much dust and gas lies between Earth and the center of the Milky Way that very little of the visible light emitted there makes it to us. We can peek through that dust and gas by collecting x-rays, infrared radiation, and radio waves. Even then, however, resolving the tiny speck of sky that contains the Milky Way’s central black hole, with enough clarity to see the black hole’s shadow, is extremely difficult. You need a very special telescope roughly the size of the Earth to do it. This might sound impractical. Fortunately, it’s possible to mimic the performance of an Earth-size telescope by coordinating existing radio telescopes scattered around the world.


That’s the idea behind the Event Horizon Telescope (EHT). If all goes well, by the end of next year the EHT will be a coordinated array of radio telescopes stretching from the South Pole to Hawaii to Chile to Mexico, plus many points in between. The astronomers behind the EHT have been already been observing for years using a smaller telescope array. In 2007, a three-station version of the EHT resolved Sagittarius A*, the black hole at the center of the Milky Way, with unprecedented clarity, detecting something (“structure” is the proper term) on the scale that we would expect from the black hole’s event horizon. It was a big deal, the farthest into the inner sanctum of a black hole that anyone had ever seen. The goal now is to make the EHT powerful enough to take the black hole’s picture.


Shep Doeleman, an astronomer with joint appointments at the Massachusetts Institute of Technology and the Harvard-Smithsonian Center for Astrophysics, leads the international group of researchers who are working to make this happen. Scientists from the U.S., Japan, Taiwan, Chile, Mexico, and several European countries are involved in the project.


The EHT uses the technique of Very Long Baseline Interferometry (VLBI) to synthesize an Earth-sized telescope in order to achieve the highest resolution possible using ground-based instrumentation. The target source is observed simultaneously at all telescopes. The data are recorded at each of the sites and later brought back to a processing facility where they are passed through a special purpose supercomputer known as a correlator. More information about radio astronomy and the technique of interferometry is available here.


Key science results so far
  • Sgr A* is a black hole: Material is falling into the Sgr A* system. If Sgr A* had a surface no bigger than the size measured by the EHT, it would be a very bright source at infrared wavelengths. However, Sgr A* is a faint infrared source, indicating that energy is disappearing through an event horizon, the existence of which defines a black hole.
  • The accretion disc in Sgr A* is inclined to the line of sight: The material orbiting and falling into the black hole is confined to a region called the accretion disk. The size obtained from the EHT indicates that we are viewing this disk closer to edge-on than face-on. EHT data also place constraints on other parameters, such as the spin of the black hole.
  • The millimeter emission in Sgr A* is offset from the black hole: As an object gets close to a black hole, it appears bigger than it actually is. The apparent size measured by the EHT is smaller than the minimum size allowed by gravitational lensing. The emission must therefore be offset from the black hole. Models indicate that we are seeing the portion of the accretion disk that is moving toward us.
  • The variability in Sgr A* occurs near the black hole: The emission we detect from Sgr A* changes in brightness, but its apparent size does not change. While the mechanism that produces this variability is not well understood, EHT data indicate that the changes occur in the accretion flow very near the black hole.
  • The black hole in M87 is spinning: Like any other object, black holes can rotate. The small size of the emission around M87 implies that the black hole is rotating rapidly and that the accreting material is orbiting the black hole in the same direction.


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Chinese scientists admitted to tweaking the genes of human embryos for the first time in history

Chinese scientists admitted to tweaking the genes of human embryos for the first time in history | Amazing Science | Scoop.it

A group of Chinese scientists just reported that they modified the genome of human embryos, something that has never been done in the history of the world, according to a report in Nature News


A recent biotech discovery - one that has been called the biggest biotech discovery of the century - showed how scientists might be able to modify a human genome when that genome was still just in an embryo.


This could change not only the genetic material of a person, but could also change the DNA they pass on, removing "bad" genetic codes (and potentially adding "good" ones) and taking an active hand in evolution.


Concerned scientists published an argument that no one should edit the human genome in this way until we better understood the consequences after a report uncovered rumours that Chinese scientists were already working on using this technology.


But this new paper, published April 18 in the journal Protein and Cell by a Chinese group led by gene-function researcher Junjiu Huang of Sun Yat-sen University, shows that work has already been done, and Nature News spoke to a Chinese source that said at least four different groups are "pursuing gene editing in human embryos."


Specifically, the team tried to modify a gene in a non-viable embryo that would have been responsible for a deadly blood disorder. But they noted in the study that they encountered serious challenges, suggesting there are still significant hurdles before clinical use becomes a reality.


CRISPR, the technology that makes all this possible, can find bad sections of DNA and cut them and even replace them with DNA that doesn't code for deadly diseases, but it can also make unwanted substitutions. Its level of accuracy is still very low.


Huang's group successfully introduced the DNA they wanted in only "a fraction" of the 28 embryos that had been "successfully spliced" (they tried 86 embryos at the start and tested 54 of the 71 that survived the procedure). They also found a "surprising number of ‘off-target’ mutations," according to Nature News.


Huang told Nature News that they stopped then because they knew that if they were do this work medically, that success rate would need to be closer to 100 percent. Our understanding of CRISPR needs to significantly develop before we get there, but this is a new technology that's changing rapidly.


Even though the Chinese team worked with non-viable embryos, embryos that cannot result in a live birth, editing the human genome and changing the DNA of an embryo is considered ethically questionable, because it could lead to more uses of this technology in humans. Changing the DNA of viable embryos could have unpredictable results for future generations, and some researchers want us to understand this better before putting it into practice.


Still, many researchers think this technology (most don't think it's ready to be used yet) could be invaluable. It could eliminate genetic diseases like sickle cell anemia, Huntington's disease, and cystic fibrosis, all devastating illnesses caused by genes that could theoretically be removed. Others fear that once we can do this accurately, it will inevitably be used to create designer humans with specific desired traits. After all, even though this research is considered questionable now, it is still actively being experimented with.


Huang told Nature News that both Nature and Science journals rejected his paper on embryo editing, "in part because of ethical objections." Neither journal commented to Nature News on that statement. Huang plans on trying to improve the accuracy of CRISPR in animal models for now. But CRISPR is reportedly quite easy to use, according to scientists who previously argued against doing this research in embryos now, meaning that it's incredibly likely these experiments will continue.

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Chinese scientists admitted to tweaking the genes of human embryos for the first time in history

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New insight into how brain makes memories

New insight into how brain makes memories | Amazing Science | Scoop.it

Every time you make a memory, somewhere in your brain a tiny filament reaches out from one neuron and forms an electrochemical connection to a neighboring neuron. A team of biologists at Vanderbilt University, headed by Associate Professor of Biological Sciences Donna Webb, studies how these connections are formed at the molecular and cellular level.


The filaments that make these new connections are called dendritic spines and, in a series of experiments described in the April 17 issue of the Journal of Biological Chemistry, the researchers report that a specific signaling protein, Asef2, a member of a family of proteins that regulate cell migration and adhesion, plays a critical role in spine formation. This is significant because Asef2 has been linked to autism and the co-occurrence of alcohol dependency and depression.


"Alterations in dendritic spines are associated with many neurological and developmental disorders, such as autism, Alzheimer's disease and Down Syndrome," said Webb. "However, the formation and maintenance of spines is a very complex process that we are just beginning to understand."


Neuron cell bodies produce two kinds of long fibers that weave through the brain: dendrites and axons. Axons transmit electrochemical signals from the cell body of one neuron to the dendrites of another neuron. Dendrites receive the incoming signals and carry them to the cell body. This is the way that neurons communicate with each other.


As they wait for incoming signals, dendrites continually produce tiny flexible filaments called filopodia. These poke out from the surface of the dendrite and wave about in the region between the cells searching for axons. At the same time, biologists think that the axons secrete chemicals of an unknown nature that attract the filopodia. When one of the dendritic filaments makes contact with one of the axons, it begins to adhere and to develop into a spine. The axon and spine form the two halves of a synaptic junction. New connections like this form the basis for memory formation and storage.


The formation of spines is driven by actin, a protein that produces microfilaments and is part of the cytoskeleton. Webb and her colleagues showed that Asef2 promotes spine and synapse formation by activating another protein called Rac, which is known to regulate actin activity. They also discovered that yet another protein, spinophilin, recruits Asef2 and guides it to specific spines. "Once we figure out the mechanisms involved, then we may be able to find drugs that can restore spine formation in people who have lost it, which could give them back their ability to remember," said Webb.

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Scientists discover asthma's potential root cause and a novel treatment

Scientists discover asthma's potential root cause and a novel treatment | Amazing Science | Scoop.it

Cardiff scientists have for the first time identified the potential root cause of asthma and an existing drug that offers a new treatment.

Published today in Science Translational Medicine journal, University researchers, working in collaboration with scientists at King's College London and the Mayo Clinic (USA), describe the previously unproven role of the calcium sensing receptor (CaSR) in causing asthma, a disease which affects 300 million people worldwide. 

The team used mouse models of asthma and human airway tissue from asthmatic and non-asthmatic people to reach their findings.

Crucially, the paper highlights the effectiveness of a class of drugs known as calcilytics in manipulating CaSR to reverse all symptoms associated with the condition. These symptoms include airway narrowing, airway twitchiness and inflammation - all of which contribute to increased breathing difficulty.

"Our findings are incredibly exciting," said the principal investigator, Professor Daniela Riccardi, from the School of Biosciences. "For the first time we have found a link airways inflammation, which can be caused by environmental triggers - such as allergens, cigarette smoke and car fumes – and airways twitchiness in allergic asthma.

"Our paper shows how these triggers release chemicals that activate CaSR in airway tissue and drive asthma symptoms like airway twitchiness, inflammation, and narrowing. Using calcilytics, nebulized directly into the lungs, we show that it is possible to deactivate CaSR and prevent all of these symptoms."

Dr Samantha Walker, Director of Research and Policy at Asthma UK, who helped fund the research, said: 

"This hugely exciting discovery enables us, for the first time, to tackle the underlying causes of asthma symptoms. Five per cent of people with asthma don't respond to current treatments so research breakthroughs could be life changing for hundreds of thousands of people. 

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Scientists link unexplained childhood paralysis to enterovirus D68

Scientists link unexplained childhood paralysis to enterovirus D68 | Amazing Science | Scoop.it

A research team led by UC San Francisco scientists has found the genetic signature of enterovirus D68 (EV-D68) in half of California and Colorado children diagnosed with acute flaccid myelitis -- sudden, unexplained muscle weakness and paralysis -- between 2012 and 2014, with most cases occurring during a nationwide outbreak of severe respiratory illness from EV-D68 last fall. The finding strengthens the association between EV-D68 infection and acute flaccid myelitis, which developed in only a small fraction of those who got sick. The scientists could not find any other pathogen capable of causing these symptoms, even after checking patient cerebrospinal fluid for every known infectious agent.


Researchers analyzed the genetic sequences of EV-D68 in children with acute flaccid myelitis and discovered that they all corresponded to a new strain of the virus, designated strain B1, which emerged about four years ago and had mutations similar to those found in poliovirus and another closely related nerve-damaging virus, EV-D70. The B1 strain was the predominant circulating strain detected during the 2014 EV-D68 respiratory outbreak, and the researchers found it both in respiratory secretions and -- for the first time -- in a blood sample from one child as his acute paralytic illness was worsening.


The study also included a pair of siblings, both of whom were infected with genetically identical EV-D68 virus, yet only one of whom developed acute flaccid myelitis. 


"This suggests that it's not only the virus, but also patients' individual biology that determines what disease they may present with," said Charles Chiu, MD, PhD, an associate professor of Laboratory Medicine and director of UCSF-Abbott Viral Diagnostics and Discovery Center. "Given that none of the children have fully recovered, we urgently need to continue investigating this new strain of EV-D68 and its potential to cause acute flaccid myelitis."


Among the 25 patients with acute flaccid myelitis in the study, 16 were from California and nine were from Colorado. Eleven were part of geographic clusters of children in Los Angeles and in Aurora, Colorado, who became symptomatic at the same time, and EV-D68 was detected in seven of these patients.

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Fast and Accurate 3D Imaging Technique to Track Optically-Trapped Particles

Fast and Accurate 3D Imaging Technique to Track Optically-Trapped Particles | Amazing Science | Scoop.it

Optical tweezers have been used as an invaluable tool for exerting micro-scale force on microscopic particles and manipulating three-dimensional (3-D) positions of particles. Optical tweezers employ a tightly-focused laser whose beam diameter is smaller than one micrometer (1/100 of hair thickness), which generates attractive force on neighboring microscopic particles moving toward the beam focus. Controlling the positions of the beam focus enabled researchers to hold the particles and move them freely to other locations so they coined the name “optical tweezers.”

 

To locate the optically-trapped particles by a laser beam, optical microscopes have usually been employed. Optical microscopes measure light signals scattered by the optically-trapped microscopic particles and the positions of the particles in two dimensions. However, it was difficult to quantify the particles’ precise positions along the optic axis, the direction of the beam, from a single image, which is analogous to the difficulty of determining the front and rear positions of objects when closing an eye due to a lack of depth perception. Furthermore, it became more difficult to measure precisely 3-D positions of particles when scattered light signals were distorted by optically-trapped particles having complicated shapes or other particles occlude the target object along the optic axis.

 

Professor YongKeun Park and his research team in the Department of Physics at the Korea Advanced Institute of Science and Technology (KAIST) employed an optical diffraction tomography (ODT) technique to measure 3-D positions of optically-trapped particles in high speed. The principle of ODT is similar to X-ray CT imaging commonly used in hospitals for visualizing the internal organs of patients. Like X-ray CT imaging, which takes several images from various illumination angles, ODT measures 3-D images of optically-trapped particles by illuminating them with a laser beam in various incidence angles.

 

The KAIST team used optical tweezers to trap a glass bead with a diameter of 2 micrometers, and moved the bead toward a white blood cell having complicated internal structures. The team measured the 3-D dynamics of the white blood cell as it responded to an approaching glass bead via ODT in the high acquisition rate of 60 images per second. Since the white blood cell screens the glass bead along an optic axis, a conventionally-used optical microscope could not determine the 3-D positions of the glass bead. In contrast, the present method employing ODT localized the 3-D positions of the bead precisely as well as measured the composition of the internal materials of the bead and the white blood cell simultaneously.

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How the Hubble Space Telescope has changed our view of the universe

How the Hubble Space Telescope has changed our view of the universe | Amazing Science | Scoop.it
Hubble has made more than 1.2 million observations and generated 100 terabytes of data, all while whirling around the Earth at 17,000 mph.

Without Hubble, astronomy "would be an awful lot poorer a field,” said Mike Garcia, a program scientist for Hubble at NASA headquarters in Washington. “The Hubble images capture the beauty of the heavens in a way that nothing else has done. The pictures are works of art, and nothing else has done that.”

Garcia, who has worked on NASA projects for over 30 years, has used the satellite’s images to study black holes in the Andromeda galaxy.


“Hubble found out that there's a supermassive black hole in the center of every galaxy. And that was a surprise,” Garcia said. “The black holes and the galaxies know about each other. The size of the black hole is in lockstep with the size of the galaxy."


Hubble doesn’t just stare into deep space; the telescope is just as good at observing objects closer to home. Hubble has provided scientists with images of Pluto’s four moons and photographic evidence that Jupiter’s Great Red Spot has been shrinking, as well as treating viewers to the fragments of a comet crashing into the gas planet.


Garcia’s favorite Hubble image captures the Andromeda galaxy’s nucleus, 2 million light-years away, which is actually pretty close. "It's a double nucleus, which is really rare. And it surrounds a supermassive black hole," Garcia said. "Only an astronomer would love it. It’s not an image the public would go wild over."


But there are plenty of images the public has gone wild over. Hubble images are embedded in our culture – seen in frames on walls, on computer screen savers and postage stamps. “An image captures people’s imaginations right away,” said John Trauger, a senior scientist at the Jet Propulsion Laboratory in La Cañada-Flintridge. “Hubble has really helped the idea of communicating science.”


Trauger helped process one of Hubble’s most recognizable images, featuring a dying star throwing dust back into space. “MyCn18,” an hourglass-shaped nebula with a green eye-like center, was photographed in 1996 and made the cover of both National Geographic and the Pearl Jam album “Binaural.”


Trauger was also the principal investigator of JPL’s mission to repair Hubble after it was launched with a flaw that rendered all its instruments “unfocusable.” In 1993, Space Shuttle Endeavour installed a new camera, called Wide Field Planetary Camera 2, giving us a view into the deepest regions of space. The camera was replaced again with a third version in 2009. With Hubble, scientists can see the same amount of detail in objects 10 times farther than they would be able to get from a land-based observatory. That allows humans to view a region of space 1,000 times larger than what we can see from the ground, Trauger said.


Hubble’s quest to capture the universe in images has benefited Earthlings in other ways, too. As NASA and the military push for more advanced digital camera technologies, those improvements eventually find their way into our pocket-sized devices.


Twenty-five years after its launch and six years after its last servicing mission, Hubble is at its scientific peak of productivity. NASA expects the satellite to work well in to the 2020s. By 2037, the agency estimates atmospheric drag will start to take its toll. Then they’ll think about boosting it up or bringing it back.

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Autism and prodigy share a common genetic link

Autism and prodigy share a common genetic link | Amazing Science | Scoop.it

Researchers have uncovered the first evidence of a genetic link between prodigy and autism. The scientists found that child prodigies in their sample share some of the same genetic variations with people who have autism. These shared genetic markers occur on chromosome, according to the researchers from The Ohio State University and Nationwide Children’s Hospital in Columbus.


The findings confirm a hypothesis made by Joanne Ruthsatz, co-author of the study and assistant professor of psychology at Ohio State’s Mansfield campus. In a previous study, Ruthsatz and a colleague had found that half of the prodigies in their sample had a family member or a first- or second-degree relative with an autism diagnosis.


“Based on my earlier work, I believed there had to be a genetic connection between prodigy and autism and this new research provides the first evidence to confirm that,” Ruthsatz said.


The new study appears online in the journal Human Heredity.


These findings are the first step toward answering the big question, Ruthsatz said. “We now know what connects prodigy with autism. What we want to know is what distinguishes them. We have a strong suspicion that there’s a genetic component to that, as well, and that’s the focus of our future work,” she said.


The Human Heredity study involved five child prodigies and their families that Ruthsatz has been studying, some for many years. Each of the prodigies had received national or international recognition for a specific skill, such as math or music. All took tests to confirm their exceptional skills.


The researchers took saliva samples from the prodigies, and from between four and 14 of each prodigy’s family members. Each prodigy had between one and five family members in the study who had received a diagnosis on the autism spectrum.

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A new wearable device, NailO, turns the user’s thumbnail into a miniature wireless track pad

A new wearable device, NailO, turns the user’s thumbnail into a miniature wireless track pad | Amazing Science | Scoop.it

Researchers at the MIT Media Laboratory are developing a new wearable device that turns the user’s thumbnail into a miniature wireless track pad. They envision that the technology could let users control wireless devices when their hands are full — answering the phone while cooking, for instance. It could also augment other interfaces, allowing someone texting on a cellphone, say, to toggle between symbol sets without interrupting his or her typing. Finally, it could enable subtle communication in circumstances that require it, such as sending a quick text to a child while attending an important meeting.


The researchers describe a prototype of the device, called NailO, in a paper they’re presenting next week at the Association for Computing Machinery’s Computer-Human Interaction conference in Seoul, South Korea.


According to Cindy Hsin-Liu Kao, an MIT graduate student in media arts and sciences and one of the new paper’s lead authors, the device was inspired by the colorful stickers that some women apply to their nails. “It’s a cosmetic product, popular in Asian countries,” says Kao, who is Taiwanese. “When I came here, I was looking for them, but I couldn’t find them, so I’d have my family mail them to me.”


Indeed, the researchers envision that a commercial version of their device would have a detachable membrane on its surface, so that users could coordinate surface patterns with their outfits. To that end, they used capacitive sensing — the same kind of sensing the iPhone’s touch screen relies on — to register touch, since it can tolerate a thin, nonactive layer between the user’s finger and the underlying sensors.

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A layered fabric 3D printer for soft interactive objects

A layered fabric 3D printer for soft interactive objects | Amazing Science | Scoop.it

A team from Disney ResearchCarnegie Mellon University and Cornell University have devised a 3-D printer that layers together laser-cut sheets of fabric to form soft, squeezable objects such as phone cases and toys. These objects can have complex geometries and incorporate circuitry that makes them interactive.


“Today’s 3-D printers can easily create custom metal, plastic, and rubber objects,” said Jim McCann, associate research scientist at Disney Research Pittsburgh. “But soft fabric objects, like plush toys, are still fabricated by hand. Layered fabric printing is one possible method to automate the production of this class of objects.”


The fabric printer is similar in principle to laminated object manufacturing, which takes sheets of paper or metal that have each been cut into a 2-D shape and then bonds them together to form a 3-D object. Fabric presents particular cutting and handling challenges, however, which the Disney team has addressed in the design of its printer.


The latest soft printing apparatus includes two fabrication surfaces: an upper cutting platform and a lower bonding platform. Fabric is fed from a roll into the device, where a vacuum holds the fabric up against the upper cutting platform while a laser cutting head moves below. The laser cuts a rectangular piece out of the fabric roll, then cuts the layer’s desired 2-D shape or shapes within that rectangle. This second set of cuts is left purposefully incomplete so that the shapes receive support from the surrounding fabric during the fabrication process.


Once the cutting is complete, the bonding platform is raised up to the fabric and the vacuum is shut off to release the fabric. The platform is lowered and a heated bonding head is deployed, heating and pressing the fabric against previous layers. The fabric is coated with a heat-sensitive adhesive, so the bonding process is similar to a person using a hand iron to apply non-stitched fabric ornamentation onto a costume or banner.


Once the process is complete, the surrounding support fabric is torn away by hand to reveal the 3-D object. The researchers demonstrated this technique by using 32 layers of 2-millimeter-thick felt to create a 2 ½-inch bunny. The process took about 2 ½ hours.


Two types of material can be used to create objects by feeding one roll of fabric into the machine from left to right, while a second roll of a different material is fed front to back. If one of the materials is conductive, the equivalent of wiring can be incorporated into the device. The researchers demonstrated the possibilities by building a fabric starfish that serves as a touch sensor, as well as a fabric smartphone case with an antenna that can harvest enough energy from the phone to light an LED.

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Ancient Death Toll of Pacific Island Birds Confirmed in New Study

Ancient Death Toll of Pacific Island Birds Confirmed in New Study | Amazing Science | Scoop.it
The first Polynesian settlers caused nearly 1,000 flightless birds like the dodo to go extinct, new research suggests


Almost 4,000 years ago, tropical Pacific Islands were an untouched paradise, but the arrival of the first people in places like Hawaii and Fiji caused irreversible damage to these natural havens, due to overhunting and deforestation. As a result, birds disappeared. But understanding the scale and extent of these extinctions has been hampered by uncertainties in the fossil record.


Professor Tim Blackburn, Director of ZSL's Institute of Zoology says: "We studied fossils from 41 tropical Pacific islands and using new techniques we were able to gauge how many extra species of bird disappeared without leaving any trace." They found that 160 species of non-passerine land birds (non-perching birds which generally have feet designed for specific functions, for example webbed for swimming) went extinct without a trace after the first humans arrived on these islands alone. "If we take into account all the other islands in the tropical Pacific, as well as seabirds and songbirds, the total extinction toll is likely to have been around 1,300 bird species," Professor Blackburn added.


Species lost include several species of moa-nalos, large flightless waterfowl from Hawai'i, and the New Caledonian Sylviornis, a relative of the game birds (pheasants, grouse, etc) but which weighed in at around 30kg, three times as heavy as a swan. Certain islands and bird species were particularly vulnerable to hunting and habitat destruction. Small, dry islands lost more species because they were more easily deforested and had fewer places for birds to hide from hunters. Flightless birds were over 30 times more likely to become extinct that those that could fly.


Bird extinctions in the tropical Pacific did not stop with these losses. Forty more species disappeared after Europeans arrived, and many more species are still threatened with extinction today.

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Real-time multicolor imaging with luminescent protein-based Nano-lanterns

Real-time multicolor imaging with luminescent protein-based Nano-lanterns | Amazing Science | Scoop.it

While fluorescence imaging (in which external light is used to excite a specimen that then emits light in response) is essential in cell biology, it has a number of significant drawbacks, including autofluorescence, phototoxicity and photobleaching, resulting from that excitation light. In addition, fluorescence imaging has the unfortunate side effect of triggering cellular activation when combined with optogenetics – an otherwise extremely valuable tool. On the other hand, luminescence (in this case, a type of chemiluminescence called bioluminescence) imaging doesn't require light activation, and so eschews these issues – but currently suffers from low brightness and poor color variants.


Recently, however, scientists at RIKEN and Osaka University extended their previous development of a bright yellowish-green luminescent protein Nano-lantern to devise bright cyan and orange luminescent proteins some 20 times brighter than previously possible with wild-type (i.e., naturally-occurring) Renilla luciferase, or Rluc – an oxidative enzyme associated with a luciferin-binding protein – found in a type of soft coral known as a sea pansy. (Luciferins are organic substances, found in luminescent organisms, which produce a near-heatless light upon oxidation.) Specifically, the researchers accomplished this by bioluminescence resonance energy transfer (BRET) from enhanced Renilla luciferase to a fluorescent protein, stating that their proof-of-principle experiments show that luminescence imaging has become a practical alternative when the side effects by the excitation light are not negligible – for example, when the samples are very sensitive to photodamage – and that the most effective future application of luminescence imaging lies in combining it with optogenetics, since the latter's external light illumination can be reserved for optical stimulation.


Dr. Yasushi Okada discussed the paper that he, Dr. Akira Takai, Dr. Takeharu Nagai, and their colleagues published in Proceedings of the National Academy of Sciences, starting with the challenges of developing cyan and orange luminescent proteins approximately 20 times brighter than wild-type Renilla luciferase. "Making the cyan version was straightforward," Okada tells Phys.org. "We acquired the best available cyan fluorescent protein, mTurquoise2," or mTq2, "from Dr Joachim Goedhart at University of Amsterdam. I was so impressed with the title of his paper1 that I immediately requested the plasmid – and he said that my request was the first he received. Several weeks after, we started working with our colleague Dr. Takeharu Nagai on yellow lanterns and soon came up with the idea of swapping the mVenus used in the yellow Nano-lantern," or YNL, "with mTq2 – and it worked excellently, producing the cyan Nano-lantern," or CNL.


Okada adds that developing the orange Nano-lantern (ONL) took trial-and-error. "We initially planned to use a large Stokes shift orange fluorescent protein like LSSmOrange2, but it didn't work well." A Stokes shift, which is essential in fluorescence imaging, refers to the difference between the energy (i.e., wavelength) of the excitation and emitted photons – and a large Stokes shift typically indicates a greater difference and thereby easier detection. "We therefore tested all possible combinations of available orange to red fluorescent proteins and Rluc variants – hundreds of them – and we finally identified the best combination." That combination became the orange Nano-lantern.

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MIT scientists developed a new tabletop instrument that can detect individual electrons in a radioactive gas

MIT scientists developed a new tabletop instrument that can detect individual electrons in a radioactive gas | Amazing Science | Scoop.it
The new instrument is expected to help scientists measure the mass of a neutrino -- something that has not been done accurately so far.


Scientists at the Massachusetts Institute of Technology (MIT) have developed a new tabletop instrument that can detect individual electrons in a radioactive gas. The development of the new particle detector is being considered as a major step toward measuring the mass of a neutrino, a particle smaller than an atom and with no electrical charge.


As a radioactive gas decays and emits electrons, the detector -- created as part of an experiment dubbed “Project 8” -- uses a magnet to trap them in a magnetic bottle. A radio antenna then catches very weak signals released by the electrons, which, according to scientists, can be used to accurately map the electrons’ activity over several milliseconds. The latest findings were published in the journal Physical Review Letters on Monday.


“We can literally image the frequency of the electron, and we see this electron suddenly pop into our radio antenna,” Joe Formaggio, an associate professor of physics at MIT, said in a statement. “Over time, the frequency changes, and actually chirps up. So these electrons are chirping in radio waves.”


As part of the new study, the researchers recorded the activity of more than 100,000 individual electrons in Krypton gas. According to them, the newly developed instrument can help measure the mass of a neutrino, which is believed to be extremely difficult to detect as it does not appear to interact with ordinary matter.

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Water Automatically Leaps Off A Gecko’s Self-Cleaning Skin

Water Automatically Leaps Off A Gecko’s Self-Cleaning Skin | Amazing Science | Scoop.it

It started when Jolanta Watson put a frozen box-patterned gecko on a glass slide. The lizard’s skin is adorned with beautiful auburn and tan blotches, and Watson wanted to study it under a microscope. But as she reached for a scalpel, she noticed that tiny water droplets had formed on the slide. The longer she looked, the more droplets there were. Where were they coming from? The microscope revealed the answer. Through its lens, Watson saw that droplets would condense on the gecko’s skin, roll into each other, and jump off under their own power. That’s why the slide was wet. The box-patterned gecko’s skin can actively repel water even if it’s dead and immobile. And when it’s alive, it can use this phenomenon, which Watson calls “geckovescence”, to clean itself with no effort.


There are some 1,500 species of geckos, which are best known for their sticky feet. Their toes are covered in thousands of microscopic hairs that allow them to cling to seemingly flat surfaces—including the walls of Watson’s Australian home. As she and her husband Gregory watched these lizards, they realised that scientists had largely ignored the rest of the gecko’s body. Their toes were cool, but what about the rest of their skin? In particular, how does it deal with water?


The box-patterned gecko lives in the Australian desert, where rainfall is rare and water is scarce. Still, chilly nights and humid mornings can produce a lot of dew, some of which condenses on the gecko’s skin. That’s a problem: water-logged skin is a breeding ground for microbes and fungi, which could potentially cause diseases. Fortunately, as the Watsons found, the gecko can automatically dry itself. When they looked at the lizard’s skin under the microscope, they saw that its scales are like rounded domes. Each of these is covered in miniscule hairs, just a few millionths of a metre long, about the size of a small bacterium. They’re densely packed too: thousands of them would fit in the cross-section of a single human hair.


Many natural structures, including springtailsleafhopperslotus leaves, and guillemot eggs, use similar microscopic textures to waterproof themselves. The principles are always the same: there are raised sections, like the gecko’s hairs, that trap pockets of air and stop water from seeping into the spaces between them. When droplets form, they sit on top of the raised bits as nigh-perfect spheres, rather than flattening out as they would do on a tabletop or on your skin.


The Watsons saw exactly this when they cooled gecko skin to the point when dew started to condense. Spherical droplets appeared, and grew. When they touched each other, they merged. And when they merged, they would occasionally fly off. Why? Because when two droplets unite, their volume stays the same but their combined surface area—and thus, their surface energy—goes down. They convert some of that surface energy into kinetic energy, and if the trade-off is substantial enough, they can launch themselves into the air.


All of this happens without help from any external forces, but external forcescan help. In fog, water droplets in the air collide with those on the gecko’s skin, increasing the odds that they will jump off. Here’s a series of images showing one such jump. Wind helps too; it blows droplets into each other, and carries the airborne drops away from the lizard.

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LEONARDO WILD's curator insight, April 23, 8:44 AM

Water is amazing, and geckos, too.