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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.

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.

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.”

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.

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: