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Real-life tractor beam pulls in particles

The Millennium Falcon
© Fair Use, Screengrab/Lucas Film
The Millennium Falcon in Star Wars Episode IV: A New Hope.
The invisible force that pulls in the Millennium Falcon spacecraft to the Death Star in Star Wars movies is still far from becoming a reality, but physicists have developed a miniature version of sorts: a tractor beam that can reel in tiny particles.

The laser-based retractor beam pulled the particles a distance of about 8 inches (20 centimeters), which is 100 times farther than any previous experiments with tractor beams.

"Because lasers retain their beam quality for such long distances, this could work over meters," study researcher Vladlen Shvedov, research fellow at the Australian National University, said in a statement. "Our lab just was not big enough to show it."

During the experiment, the researchers used a laser that projected a doughnut-shaped beam of light with a hot outer ring and cool center. They used the light beam to suck in tiny glass spheres, each of which measured about 0.2 millimeters (0.008 inches) wide.

Not only did the researchers move the glass spheres farther than had been demonstrated in previous experiments, but they used a different technique altogether. Other retractor beams rely on the momentum of light particles in the laser beam to reel in mass. In those experiments, the momentum from the light particles shooting out of the laser is transferred to the target that the laser is hauling in. However, that technique works well only in a vacuum that is shielded from other free-floating particles that can interfere with the momentum transfer.
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Electrostatic force microscopy (EFM) shows electric charge propagating along microbial nanowires

Geobacter
© Credit: UMass Amherst
UMass Amherst researchers recently provided stronger evidence than ever before to support their claim that the microbe Geobacter produces tiny electrical wires, called microbial nanowires, along which electric charges propagate just as they do in carbon nanotubes, a highly conductive man-made material.
The claim by microbiologist Derek Lovley and colleagues at the University of Massachusetts Amherst that the microbe Geobacter produces tiny electrical wires, called microbial nanowires, has been mired in controversy for a decade, but the researchers say a new collaborative study provides stronger evidence than ever to support their claims.

UMass Amherst physicists working with Lovley and colleagues report in the current issue of Nature Nanotechnology that they've used a new imaging technique, electrostatic force microscopy (EFM), to resolve the biological debate with evidence from physics, showing that electric charges do indeed propagate along microbial nanowires just as they do in carbon nanotubes, a highly conductive man-made material.

Physicists Nikhil Malvankar and Sibel Ebru Yalcin, with physics professor Mark Tuominen, confirmed the discovery using EFM, a technique that can show how electrons move through materials. "When we injected electrons at one spot in the microbial nanowires, the whole filament lit up as the electrons propagated through the nanowire," says Malvankar.

Yalcin, now at Pacific Northwest National Lab, adds, "This is the same response that you would see in a carbon nanotube or other highly conductive synthetic nanofilaments. Even the charge densities are comparable. This is the first time that EFM has been applied to biological proteins. It offers many new opportunities in biology."

Comment: see also: Forming new circuits - Meet the electric life forms that live on pure energy

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Ten years on, scientists still debating the origins of Homo floresiensis - the 'Hobbit'

Homo floresiensis
© John Gurche/National Museum of Natural History
Homo floresiensis adult female - model of head.
It's been ten years since the bones of Homo floresiensis, aka, the "hobbit" were uncovered in Liang Bua, a cave, on the island of Flores in Indonesia, and scientists still can't agree on the diminutive hominin's origins.

This month, the journal Nature has printed a comment piece by Chris Stringer of the Natural History Museum in London and two pieces by Ewen Callaway, one a retrospective with interviews with the central players, and the other a podcast with the four principle scientists involved in the find - Bert Roberts, Thomas Sutikna, Dean Falk, and Stringer.

Did H. floresiensis descend from Australopithecus, leaving Africa and somehow settling on Flores, or was it a case of an early member of our family tree finding its way to the island and then because of limited resources, evolving into a much smaller size? That's the central question in the debate.

The majority opinion has sided with the island effect, mostly because of the time frame - H. floresiensis existed a mere 13,000 years ago, which means it was alive when other Homo sapiens were about, thus it seemed to make sense that H. floresiensis was also a member that had become stranded on an island. But Stringer doesn't agree. In his commentary piece he notes the chin and jaw are more reminiscent of pre-human fossils, dating back approximately two million years.

Also, the body shape and tiny brain appear to be more primitive than humans. He says taken together, the evidence suggests a closer match with Australopithecus, a pre-human group living in Africa which also includes the remains of the famous "Lucy" - and which also date back to approximately 1.2 million years ago.
Sun

North America to experience spectacular sunset due to partial solar eclipse October 23

solar eclipse
© Reuters / Abdel-Halim Shahaby
Much of North America will experience a solar eclipse on Thursday, with the moon covering up to 70 percent of the sun in the late afternoon. Along most of the East Coast and Midwest, the event will occur during sunset, allowing for dramatic photography.

"Sunsets are always pretty. One sunset this month could be out of this world. On Thursday, Oct. 23rd, the setting sun across eastern parts of the USA will be red, beautiful and... crescent-shaped," NASA Science wrote. The alignment of the two orbs on the East Coast at the end of the day "will be especially beautiful... transforming the usual sunset into something weird and wonderful."

The farther north viewers are, the deeper the eclipse they'll see, and the farther west they are, the higher the sun and moon will be in the sky. Thus the comparatively later dusk of the Midwest may provide the most spectacular views of sunset-enhanced phenomenon.

"Observers in the Central Time zone have the best view because the eclipse is in its maximum phase at sunset," longtime NASA eclipse expert Fred Espenak said. "They will see a fiery crescent sinking below the horizon, dimmed to human visibility by low-hanging clouds and mist."
Health

New study suggests 21-day Ebola quarantine is off-base, virus could incubate longer

Hospital workers and public health officials in the U.S. have come under fire for a series of missteps in their response to the Ebola crisis, from initially misdiagnosing Thomas Eric Duncan to allowing a nurse who cared for him at a Dallas hospital to fly on a commercial airliner shortly before she too was diagnosed with the deadly illness.

Now an engineering professor with expertise in assessing the risks posed by pathogens claims he's identified another big problem with authorities' response to the crisis.

In a paper published Oct. 14 in the journal PLOS Currents: Outbreaks, Drexel University's Dr. Charles N. Haas argues that there's not enough evidence to support the recommended 21-day quarantine period for people suspected of harboring the virus.
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Genomic remnants from ancient viruses play a prominent role in embryonic development

ancient viruses
© Credit: A*STAR Genome Institute of Singapore
Genomic remnants from ancient viruses may help human embryonic stem cells maintain the flexibility needed to form the full spectrum of tissues in the body.
Like fossils buried beneath a modern landscape, the human genome is littered with sequences that originated from ancient viral DNA insertion events. Scientists have long assumed that these 'transposable elements' are, like fossils, biologically inactive and primarily interesting as a window into evolutionary history. However, researchers at the A*STAR Genome Institute of Singapore have now uncovered evidence that some of these sequences play a prominent role in early embryonic development.

Huck-Hui Ng and colleagues embarked on this project in collaboration with Guillaume Bourque at Canada's McGill University. Bourque's group had discovered that one particular class of sequences of transposable elements - known as human endogenous retrovirus subfamily H (HERV-H) - appears to be specifically expressed in human embryonic stem cells (hESCs). Indeed, these HERV-H sequences are actively transcribed in hESCs, producing enigmatic RNA strands that do not encode a protein but nevertheless appear to serve some function.

Ng and Bourque set out to clarify the role of this RNA by performing experiments in which they selectively depleted it from stem cells. hESCs are actively maintained in a so-called 'pluripotent' state, from which they are capable of developing into any cell type in the human body (see image). In the absence of HERV-H RNA, hESCs rapidly lost their pluripotency; the researchers noted that the loss of HERV-H expression considerably altered the activity of many genes associated with cell development and proliferation.
Galaxy

Solar-system-wide 'climate' change: More galactic cosmic rays are reaching Earth than normal

New space weather observations continue to stun scientists reared on the Aristotelian 'uniformitarian' model, where nothing dynamic ever (or very rarely) happens in space. This is from phys.org:
In a recently published paper in Space Weather, associate professor Nathan Schwadron of the UNH Institute for the Study of Earth, Oceans, and Space (EOS) says that due to a highly abnormal and extended lack of solar activity, the solar wind is exhibiting extremely low densities and magnetic field strengths, which in turn is causing dangerous levels of hazardous radiation to pervade the space environment.
While the study notes that "human beings face a variety of consequences ranging from acute effects (radiation sickness) to long-term effects including cancer induction and damage to organs including the heart and brain," the funding angle for this study was to assess the impact of increased radiation on astronauts travelling to Mars (ha! like that will ever happen in today's global economic depression). That's not what interests us here at SOTT.net. What we're interested in is the trend of reducing solar output and the high radiation levels seen during the sun's last minimum cycle... in terms of the immediate, present effects of increased cosmic rays reaching the planet's surface.
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Jewelry that harvests energy from your veins

© Naomi Kizhner
Naomi Kizhner, an industrial designer and graduate student from Hadassah College in Jerusalem, has designed jewelry that theoretically extracts energy from the wearers own body. The 'speculative' jewelry is embedded into the person's veins and uses their blood to turn small wheels inside the device.
Comet

Earth at risk after cuts close comet-spotting program that spotted the Siding Spring

© Nasa, JPL-Caltech, UCLA/AAP
A Nasa infrared image of Comet Siding Spring. The comet, also known by the less catchy name of C/2007 Q3, was discovered in 2007 by astronomers at the Siding Spring Observatory.
The Earth has been left with a huge blind spot for potentially devastating comet strikes after the only dedicated comet-spotting program in the southern hemisphere lost its funding, leading astronomers have warned.

The program, which discovered the Siding Spring comet that narrowly missed Mars on Sunday, was shut down last year after losing funding.

"It's a real worry," Bradley Tucker, an astronomer at the Australian National University (ANU) and University of California Berkeley, told Guardian Australia.

"There could be something hurtling towards us right now and we wouldn't know about it."


Comment: Indeed, something wicked this way comes, and SOTT has been warning about it for years.


The Siding Spring survey - named after the observatory near Coonabarabran in central New South Wales, where the Mars comet was first spotted - was the only program in the southern hemisphere actively searching for potentially hazardous comets, asteroids and meteors.

Comment: Don't say we didn't warn you. As was mentioned above, SOTT has been talking about the cosmic threat for years now, and how this knowledge is being purposefully concealed and distorted by the Powers that Be. Considering the recent anti-Putin charade and continuous bloodshed in the Middle East, Victor Clube, author of The Cosmic Serpent and The Cosmic Winter was right when he said in the report commissioned by the U.S. Air Force:
We do not need the celestial threat to disguise Cold War intentions; rather we need the Cold War to disguise celestial intentions!


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Cell biology research shakes up mitochondrial mystery

mitochondria

A volume rendering of mitochondria
Elvis did it, Michael Jackson did it, and so do the mitochondria in our cells. They shake. While Elvis and Michael shook for decades before loud and appreciative audiences, mitochondrial oscillations have quietly bewildered scientists for more than 40 years.

Now, a team of scientists at National Institutes of Health's National Institute of Dental and Craniofacial Research (NIDCR) has imaged mitochondria for the first time oscillating in a live animal, in this case, the salivary glands of laboratory rats. The report, published online today in the journal Cell Reports, shows the oscillations occur spontaneously and often in the rodent cells, which leads the researchers to believe the oscillations almost surely also occur in human cells.

"The movements could last from tens of seconds to minutes, which was far longer and frequently at a faster tempo than observed previously in cell culture," said Roberto Weigert, Ph.D., an NIDCR scientist and senior author on the study. The mitochondria also appear to synchronize their movements not only in an individual cell but, quite unexpectedly, into a linked network of oscillators vibrating throughout the tissue.

"You look through the microscope, and it almost looks like a synchronized dance," said Weigert. "The synchronization, to borrow an old cliché, tells us that we need to differentiate the forest from the trees - and vice versa - when studying mitochondria. It may be that the forest holds the key to understanding how mitochondria function in human health and disease."
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