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How pulsars attain their speed jumps

A team of astronomers from the University of Amsterdam has discovered that sudden speed jumps in the rotational velocity of pulsars have a minimum size, and that they are caused not by the unpinning and displacement of just one sub-surface superfluid vortex, but by billions.


This result is important to our understanding of the behaviour of matter under extreme
conditions.


Pulsars are rotating neutron stars --remnants of massive stars that end their lives in supernova explosions. They act like cosmic lighthouses whose beams sweep through
the universe.

Their rotational velocity decreases in time, but can suddenly increase in rare events called glitches. These glitches are caused by the unpinning and displacement of vortices that connect the crust with the mixture of particles containing superfluid neutrons beneath the crust.

The team of astronomers discovered that the glitches of the Crab Pulsar always involve a decrease in the rotational period of at least 0.055 nanosecond.

The Crab Pulsar was one of the first pulsars to be discovered and has been observed almost daily with the 42-foot telescope at the Jodrell Bank Observatory over the last 29 years. The huge amount of data makes this object the best choice to study glitches.
The smallest glitch is likely to be caused by the unpinning and movement of billions of vortices.

“Surprisingly, no one tried to determine a lower limit to glitch size before. Many assumed that the smallest glitch would be caused by a single vortex unpinning. The smallest glitch is clearly much larger than we expected,” Danai Antonopoulou from the University of Amsterdam (UvA), said.


Proteins may hold key to treating schizophrenia

A new study has revealed that the physiological signature of schizophrenia lies in the measurable proteins in brains.

The researchers from the University of Southern Denmark have analysed proteins in the brains of rats that have been given hallucinogenic drugs and believe that knowing these proteins and comparing their behavior to proteins in the brains of not-schizophrenic people may make it possible to develop more effective drugs.

The researchers said that when they gave rats hallucinogenic drug phenocyclidine (PCP), which provides a range of symptoms in people that are very similar to schizophrenia, the rats become valuable study objects for schizophrenia researchers.

Ole Norregaard Jensen said that scientists have studied PCP rats for decades, but until now no one really knew what was going on in the rat brains at the molecular level, but could now see changes in the proteins in the brain already after 15 minutes. And after 240 minutes, it was almost over.

The researchers said that they found 2604 proteins, and in 352 of them, we saw changes that can be associated with the PCP injections and theses proteins responded immediately when the animals were exposed to the drug.

The drug made proteins turn on or off when they should not turn on and off, which started a chain reaction of other disturbances in the molecular network around the proteins, such as changes in metabolism and calcium balance.

New Chinese herbal medicine could help treat Hepatitis C


Scientists have revealed that a new Chinese herbal medicine could the significant potential of treating Hepatitis C.

The researchers have found that a new compound, SBEL1, which has been isolated from Chinese herbal medicines, has the ability to inhibit hepatitis C virus (HCV) activity in cells at several points in the virus’ lifecycle.

The study showed that the compound could inhibit HCV activity by approximately
90 per ent.

The scientists, who pre-treated human liver cells in vitro with SBEL1 prior to HCV
infection, found that SBEL1 pre-treated cells contained 23 per cent less HCV protein than the control, suggesting that SBEL1 blocks virus entry.

Markus Peck-Radosavljevic, Secretary-General of the European Association for the Study of the Liver and Associate Professor of Medicine, said that people infected with hepatitis C are at risk of developing severe liver damage including liver cancer and cirrhosis and that SBEL1 has demonstrated significant inhibition of HCV at multiple stages of the viral lifecycle.

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