A unique electron microscope that can help create four-dimensional “movies“ of molecules may hold the answers to research questions in a number of fields including chemistry, biology, and physics, according to an article in the Dec. 24 issue of Chemical & Engineering News, ACS’ weekly newsmagazine, Physorg.com wrote.
In the article, C&EN Associate Editor Rachel Petkewich notes that the microscope, located at the California Institute of Technology, is a modified transmission electron microscope interfaced with an ultrafast laser. The ultrafast microscope is the only one capable of capturing four-dimensional pictures of molecules--3-D structural changes over time--as they form and break apart, the writer states.
These reactions occur at extremely fast rates--one billionth of one millionth of a second, or a ’femtosecond’--that can’t be seen directly in real-time by other instruments. In 1999, Caltech chemist Ahmed H. Zewail, the lead scientist on the new work, was awarded the Nobel Prize in Chemistry for his pioneering studies of these ultrafast reactions.
Zewail and his colleagues are now making refinements to their ultrafast microscope and plan to capture a wider variety of images, including the details of whole cells, the writer notes. Caltech is negotiating an agreement with a microscope manufacturer to commercialize the instrument and make it available to other scientists, according to the article.

Scientists have discovered evidence suggesting a herpes virus may be responsible for some cases of meningitis and encephalitis.
Human herpes virus 6 (HHV-6) is one of the most prevalent in humans. There are two variants of HHV-6, HHV-6A and HHV-6B which is attributed to a common childhood disease characterized by a high fever and rash, ScienceDaily said.
Studies indicate that by age 3 the majority of children have been infected by HHV-6, after which the virus persists in the salivary glands into adulthood. The virus may remain dormant or reactivate in immunocompetent or immunocompromised individuals.
Over a span of four years, researchers from the New York State Department of Public Health, Albany and SUNY, Albany collected specimens from patients hospitalized with symptoms of encephalitis and meningitis, and tested them for the presence of HHV-6.
The majority of the specimens were taken from cerebrospinal fluid and some of the symptoms exhibited by the patients include fever, altered mental status, and abnormal CSF profile, as well as seizures in those ages 3 and under.
Results showed that 26 specimens from 24 patients were positive for HHV-6, of which 20 were identified as the HHV-6B strain. Forty-two percent of the patients were aged 3 or under, possibly indicating primary infection, while the remaining patients ranging from 4 to 81 years old were probably experiencing viral reactivation.
“The detection of HHV-6 in specimens from patients diagnosed with encephalitis or meningitis, in the absence of a positive PCR result for other agents, strongly suggests a role for HHV-6 in the pathogenesis of these central system diseases,“ say the researchers.

A view of the HD189733 s tar-planet system near a half-moon phase when polarization of the light reflected by the planet reaches the maximum.

An international team of astronomers, led by Professor Svetlana Berdyugina of ETH Zurich’s Institute of Astronomy, has for the first time ever been able to detect and monitor the visible light that is scattered in the atmosphere of an exoplanet.
Employing techniques similar to how Polaroid sunglasses filter away reflected sunlight to reduce glare, the team of scientists were able to extract polarized light to enhance the faint reflected starlight ’glare’ from an exoplanet, according to Eurekalert.
As a result, the scientists could infer the size of its swollen atmosphere.
They also directly traced the orbit of the planet, a feat of visualization not possible using indirect methods.
The transiting exoplanet under study circles the dwarf star HD189733 in the constellation Vulpecula and lies more than 60 light years from the earth. Known as HD189733b, this exoplanet was discovered two years ago via Doppler spec-troscopy. HD189733b is so close to its parent star that its atmosphere expands from the heat.
Until now, astronomers have never seen light reflected from an exoplanet, although they have deduced from other observations that HD189733b probably resembles a “hot Jupiter“--a planet orbiting extremely closely to its parent star.
Unlike Jupiter, however, HD189733b orbits its star in a couple of days rather than the 12 years it takes Jupiter to make one orbit of the sun.
The international team, consisting of Svetlana Berdyugina, Dominique Fluri (ETH Zurich), Andrei Berdyugin and Vilppu Piirola (Tuorla Observatory, Finland), used the 60cm KVA telescope by remote control.
The researchers obtained polarimetric measurements of the star and its planet. They discovered that polarization peaks near the moments when half of the planet is illuminated by the star as seen from the earth. Such events occur twice during the orbit, similar to half-moon phases.
The polarization indicates that the scattering atmosphere is considerably larger (>30%) than the opaque body of the planet seen during transits and most probably consists of particles smaller than half a micron, for example atoms, molecules, tiny dust grains or perhaps water vapor, which was recently suggested to be present in the atmosphere.

Some claim drinking eight glasses of water a day leads to good health, while reading in dim light damages eyesight.
Others believe we only use 10 percent of our brains or that shaving legs cause hair to grow back thicker, BBC said.
But a review of evidence by US researchers surrounding seven commonly-hold beliefs suggests they are actually “medical myths“.
Some are utterly untrue, while others have no evidential proof, the British Medical Journal reports.
Researchers from the Indiana University School of Medicine in Indianapolis hunted medical literature for evidence on each claim.
They found no evidence supporting the need to drink eight glasses of water a day.
In fact, studies suggest that adequate fluid intake is often met by drinking juice, milk, and even caffeine-rich tea and coffee.
Data also suggests drinking excessive amounts of water can be dangerous.
The belief that we only use 10 percent of our brains appears to be completely untrue.
Studies of patients with brain damage suggest that damage to almost any area of the brain has specific and lasting effects on mental, vegetative and behavioral capabilities.
Brain imaging studies also show that no area of the brain is completely silent or inactive.
And the belief that hair and fingernails continue to grow after death may be an optical illusion caused by retraction of the skin after death.
The actual growth of hair and nails requires a complex interplay of hormonal regulation not present after death.
Again, illusion may be to blame for the belief that shaving hair causes it to grow back faster, darker, and coarser, report author Rachel Vreeman told the BMJ.
The stubble resulting from shaving grows out without the finer taper seen at the ends of unshaven hair, giving the impression of thickness and coarseness.
Again, expert opinion is that reading in dim light does not damage your eyes. And there is little evidence to support the banning mobile phones from hospitals on the basis of electromagnetic interference.
Finally, eating turkey--and the tryptophan amino acid it contains--does not make people especially drowsy.
Indeed, turkey, chicken and minced beef contain similar amounts of tryptophan.
The researchers explained: “Any large meal can induce sleepiness because blood flow and oxygenation to the brain decrease, and meals rich in protein or carbohydrate may cause drowsiness.“
Dr David Tovey, editor of Clinical Evidence journal, said, “The difficulty is it is often hard to disprove a theory.
“On the flip-side, absence of evidence does not necessarily mean absence of effect.
“Where reliable evidence becomes really important is in helping people make serious decisions about harms and risks.“
He added, “Many of these ’myths’ are innocuous. However, we are still finding evidence that runs contrary to current practice and what we expect.“

Researchers at Chalmers University in Sweden have succeeded in combining a receiver for high frequencies with an antenna on a small chip.
The receiver is just a few square millimeter and is suitable for new safety systems, image sensors, and radio communication for high bitrates.
The receiver is an electronic circuit including antenna, low noise amplifier, and frequency converter monolithically integrated on gallium arsenide, ScienceDaily wrote.
“This is a breakthrough in our research. Our result opens the possibility to manufacture systems for very high frequencies within the so called “THZ-electronics“ area, to a relatively low cost.
In the next phase of this project even more functions can be integrated on the same chip“, according to Herbert Zirath, professor at the department of Microwave Electronics.
This circuit can be used, for instance, in radiometer systems in future safety systems looking for concealed weapons without personal intrusive search.
Other applications for this circuit are imaging sensors that can look through darkness, smoke or fog. This is an important safety function for vehicles such as cars and aircrafts.
“Thanks to this technology, we now have the possibility of integrating imaging sensors by using circuits of a few square millimeter which is much smaller than the present technology at a lower cost.
“For automotive applications such as cars, aircrafts and satellites, the size and weight is of utmost importance. The present systems consist of many pieces and demands several cubic decimeters volume,“ says Herbert Zirath.
The new circuit is designed to work at the frequency of 220 gigahertz, but this is not an upper limit. According to professor Zirath, the technology can be used up to and above 300GHz in a near future.
The technology is also interesting for wireless data communication because, due to the very high bandwidth, data rate well above 10 Gbit/s is possible to realize in future radio links.