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Mar 1, 2020

Physicists model the supernovae that result from pulsating supergiants like Betelgeuse

Posted by in categories: cosmology, physics

Betelgeuse has been the center of significant media attention lately. The red supergiant is nearing the end of its life, and when a star over 10 times the mass of the Sun dies, it goes out in spectacular fashion. With its brightness recently dipping to the lowest point in the last hundred years, many space enthusiasts are excited that Betelgeuse may soon go supernova, exploding in a dazzling display that could be visible even in daylight.

While the famous star in Orion’s shoulder will likely meet its demise within the next million years—practically couple days in cosmic time—scientists maintain that its dimming is due to the star pulsating. The phenomenon is relatively common among red supergiants, and Betelgeuse has been known for decades to be in this group.

Coincidentally, researchers at UC Santa Barbara have already made predictions about the brightness of the supernova that would result when a pulsating star like Betelgeuse explodes.

Mar 1, 2020

Why is there any matter in the universe at all? New study sheds light

Posted by in categories: cosmology, particle physics

Scientists at the University of Sussex have measured a property of the neutron—a fundamental particle in the universe—more precisely than ever before. Their research is part of an investigation into why there is matter left over in the universe, that is, why all the antimatter created in the Big Bang didn’t just cancel out the matter.

The team—which included the Science and Technology Facilities Council’s (STFC) Rutherford Appleton Laboratory in the UK, the Paul Scherrer Institute (PSI) in Switzerland, and a number of other institutions—was looking into whether or not the neutron acts like an “electric compass.” Neutrons are believed to be slightly asymmetrical in shape, being slightly positive at one end and slightly negative at the other—a bit like the electrical equivalent of a bar magnet. This is the so-called “” (EDM), and is what the team was looking for.

This is an important piece of the puzzle in the mystery of why matter remains in the Universe, because scientific theories about why there is matter left over also predict that neutrons have the “electric compass” property, to a greater or lesser extent. Measuring it then it helps scientists to get closer to the truth about why matter remains.

Mar 1, 2020

Helical quantum Hall phase in graphene on strontium titanate

Posted by in categories: particle physics, quantum physics

Materials that exhibit topological phases can be classified by their dimensionality, symmetries and topological invariants to form conductive-edge states with peculiar transport and spin properties. For example, the quantum Hall effect can arise in two-dimensional (2-D) electron systems subjected to a perpendicular magnetic field. When distinct characteristics of quantum Hall systems are compared with time-reversal symmetric (entropy conserved) topological insulators (TIs), they appear to rely on Coulomb interactions between electrons to induce a wealth of strongly correlated, topologically or symmetry-projected phases in a variety of experimental systems.

In a new report now on Science, Louis Veyrat and a research team in materials science, and optoelectronics in France, China and Japan tuned the ground state of the graphene zeroth Landau level i.e. orbitals occupied by charged particles with discrete energy values. Using suitable screening of the Coulomb interaction with the high dielectric constant of a strontium titanate (SrTiO3) substrate, they observed robust helical edge transport at magnetic fields as low as 1 Tesla, withstanding temperatures of up to 110 kelvin across micron-long distances. These versatile graphene platforms will have applications in spintronics and topological quantum computation.

Topological insulators (TIs), i.e., a material that behaves as an insulator in its interior but retains a conducting surface state, with zero Chern number have emerged as quantum Hall (QHTIs) arising from many-body interacting Landau levels. They can be pictured as two independent copies of quantum Hall systems with opposite chirality, but the experimental system is at odds with the described scenario, where a strong insulating state is observed on increasing the perpendicular in charge-neutral, high-mobility graphene devices.

Mar 1, 2020

New platform for engineering ribosomes to ‘cook new cuisines’

Posted by in categories: bioengineering, biotech/medical

Synthetic biology researchers at Northwestern University have developed a system that can rapidly create cell-free ribosomes in a test tube, then select the ribosome that can perform a certain function.

The system, called synthesis and evolution (RISE), is an important step toward using ribosomes beyond their natural capabilities. The key feature of RISE is the ability to evolve ribosomes without cell viability constraints. The result could be new ways to synthesize materials, like nylon, or therapies, like that could address rising antibiotic resistance.

“Ribosomes have an extraordinary capability as the protein synthesis machinery of the cell,” said Michael Jewett, Walter P. Murphy Professor of Chemical and Biological Engineering and director of the Center for Synthetic Biology at Northwestern’s McCormick School of Engineering, who led the research. “But to synthesize proteins beyond those found in nature, we have to design and modify the ribosome to work with non-natural substrates. Developing ribosomes in vitro is an important part of that system, and we are very excited to have this new capability.”

Mar 1, 2020

Venn and the art of avoiding a parallel governance universe

Posted by in categories: cosmology, governance

Boards and management teams can easily find themselves either stepping on each other’s toes – or, conversely, functioning in parallel universes. So how do you find the perfect balance? Top tips on achieving a Venn-like state from Patrick Dunne – a serial social entrepreneur, chair of the EY foundation and the author of a new book on governance.

Mar 1, 2020

How China is using AI and big data to combat coronavirus outbreak

Posted by in categories: biotech/medical, information science, robotics/AI, surveillance

Authorities in China step up surveillance and roll out new artificial intelligence tools to fight deadly epidemic.

Mar 1, 2020

Coronavirus genome structure and replication

Posted by in category: biotech/medical

Curr Top Microbiol Immunol. 2005;287:1–30.

In addition to the SARS coronavirus (treated separately elsewhere in this volume), the complete genome sequences of six species in the coronavirus genus of the coronavirus family [avian infectious bronchitis virus-Beaudette strain (IBV-Beaudette), bovine coronavirus-ENT strain (BCoV-ENT), human coronavirus-229E strain (HCoV-229E), murine hepatitis virus-A59 strain (MHV-A59), porcine transmissible gastroenteritis-Purdue 115 strain (TGEV-Purdue 115), and porcine epidemic diarrhea virus-CV777 strain (PEDV-CV777)] have now been reported. Their lengths range from 27,317 nt for HCoV-229E to 31,357 nt for the murine hepatitis virus-A59, establishing the coronavirus genome as the largest known among RNA viruses.

Mar 1, 2020

DNA discovery can lead to new types of cancer drugs

Posted by in categories: biotech/medical, health

Cells can both survive and multiply under more stress than previously thought, shows research from the Faculty of Health and Medical Sciences.

This was found by inhibiting the essential gene DNA polymerase alpha, or POLA1, which initiates DNA replication during .

The discovery gives researchers new insights into DNA replication and may potentially be used for a new type of cancer treatment. Research Leader and Associate Professor Luis Toledo of the Center for Chromosome Stability at the Department of Cellular and Molecular Medicine states as follows:

Mar 1, 2020

Binary Stars Appear To Harbor Just As Many Planets As Single Stars, Says Study

Posted by in category: space

New paper sheds light on the age-old question about the frequency of planets around binary versus single stars.

Mar 1, 2020

Can Destroying Senescent Cells Treat Age-Related Disease?

Posted by in categories: biotech/medical, life extension

I think so.


A handful of clinical trials are underway to find out whether drugs that target senescent cells can slow the ravages of old age.