Increased elastase sensitivity and decreased intramolecular interactions in the more transmissible 501Y.V1 and 501Y.V2 SARS-CoV-2 variants' spike protein-an in silico analysis.

Two SARS-CoV-2 variants of concern showing increased transmissibility relative to the Wuhan virus have recently been identified. Although neither variant appears to cause more severe illness nor increased risk of death, the faster spread of the virus is a major threat. Using computational tools, we found that the new SARS-CoV-2 variants may acquire an increased transmissibility by increasing the propensity of its spike protein to expose the receptor binding domain via proteolysis, perhaps by neutrophil elastase and/or via reduced intramolecular interactions that contribute to the stability of the closed conformation of spike protein. This information leads to the identification of potential treatments to avert the imminent threat of these more transmittable SARS-CoV-2 variants

Numerical evidence for `multi-scalar stars'

We present a class of general relativistic soliton-like solutions composed of multiple minimally coupled, massive, real scalar fields which interact only through the gravitational field. We describe a two-parameter family of solutions we call ``phase-shifted boson stars'' (parameterized by central density rho_0 and phase delta), which are obtained by solving the ordinary differential equations associated with boson stars and then altering the phase between the real and imaginary parts of the field. These solutions are similar to boson stars as well as the oscillating soliton stars found by Seidel and Suen [E. Seidel and W.M. Suen, Phys. Rev. Lett. 66, 1659 (1991)]; in particular, long-time numerical evolutions suggest that phase-shifted boson stars are stable. Our results indicate that scalar soliton-like solutions are perhaps more generic than has been previously thought.Comment: Revtex. 4 pages with 4 figures. Submitted to Phys. Rev.

A first-in-human study of AMG 208, an oral MET inhibitor, in adult patients with advanced solid tumors.

BackgroundThis first-in-human study evaluated AMG 208, a small-molecule MET inhibitor, in patients with advanced solid tumors.MethodsThree to nine patients were enrolled into one of seven AMG 208 dose cohorts (25, 50, 100, 150, 200, 300, and 400 mg). Patients received AMG 208 orally on days 1 and days 4-28 once daily. The primary objectives were to evaluate the safety, tolerability, pharmacokinetics, and maximum tolerated dose (MTD) of AMG 208.ResultsFifty-four patients were enrolled. Six dose-limiting toxicities were observed: grade 3 increased aspartate aminotransferase (200 mg), grade 3 thrombocytopenia (200 mg), grade 4 acute myocardial infarction (300 mg), grade 3 prolonged QT (300 mg), and two cases of grade 3 hypertension (400 mg). The MTD was not reached. The most frequent grade ≥3 treatment-related adverse event was anemia (n = 3) followed by hypertension, prolonged QT, and thrombocytopenia (two patients each). AMG 208 exposure increased linearly with dose; mean plasma half-life estimates were 21.4-68.7 hours. One complete response (prostate cancer) and three partial responses (two in prostate cancer, one in kidney cancer) were observed.ConclusionsIn this study, AMG 208 had manageable toxicities and showed evidence of antitumor activity, particularly in prostate cancer

Experimental identification of non-pointlike dark-matter candidates

We show that direct dark matter detection experiments can distinguish between pointlike and non-pointlike dark-matter candidates. The shape of the nuclear recoil energy spectrum from pointlike dark-matter particles, e.g., neutralinos, is determined by the velocity distribution of dark matter in the galactic halo and by nuclear form factors. In contrast, typical cross sections of non-pointlike dark matter, for example, Q-balls, have a new form factor, which decreases rapidly with the recoil energy. Therefore, a signal from non-pointlike dark matter is expected to peak near the experimental threshold and to fall off rapidly at higher energies. Although the width of the signal is practically independent of the dark matter velocity dispersion, its height is expected to exhibit an annual modulation due to the changes in the dark matter flux.Comment: 4 pages; minor changes, references adde

Structured information extraction from complex scientific text with fine-tuned large language models

Intelligently extracting and linking complex scientific information from unstructured text is a challenging endeavor particularly for those inexperienced with natural language processing. Here, we present a simple sequence-to-sequence approach to joint named entity recognition and relation extraction for complex hierarchical information in scientific text. The approach leverages a pre-trained large language model (LLM), GPT-3, that is fine-tuned on approximately 500 pairs of prompts (inputs) and completions (outputs). Information is extracted either from single sentences or across sentences in abstracts/passages, and the output can be returned as simple English sentences or a more structured format, such as a list of JSON objects. We demonstrate that LLMs trained in this way are capable of accurately extracting useful records of complex scientific knowledge for three representative tasks in materials chemistry: linking dopants with their host materials, cataloging metal-organic frameworks, and general chemistry/phase/morphology/application information extraction. This approach represents a simple, accessible, and highly-flexible route to obtaining large databases of structured knowledge extracted from unstructured text. An online demo is available at http://www.matscholar.com/info-extraction

The H2 velocity structure of inner knots in HH 212: asymmetries and rotation

High-resolution R~50 000 long-slit spectroscopy of the inner knots of the highly symmetrical protostellar outflow HH 212 was obtained in the 1-0 S(1) line of H2 at 2.12 micron with a spatial resolution of ~0.45 arcsec. At the resulting velocity resolution of ~6 km s-1, multiple slit oriented observations of the northern first knot NK1 clearly show double-peaked line profiles consistent with either a radiative bow shock or dual (forward and reverse) shocks. In contrast, the velocity distribution of the southern first knot SK1 remains single-peaked, suggesting a significantly lower jet velocity and possibly a different density variation in the jet pulses in the southern flow compared to the northern flow. Comparison with a semi-empirical analytical model of bow shock emission allows us to constrain parameters such as the bow inclination to the line of sight, the bow shock and jet velocities for each flow. Although a few features are not reproduced by this model, it confirms the presence of several dynamical and kinematical asymmetries between opposite sides of the HH 212 bipolar jet. The position-velocity diagrams of both knots exhibit complex dynamics that are broadly consistent with emission from a bow shock and/or jet shock, which does not exclude jet rotation, although a clear signature of jet rotation in HH 212 is missing. Alternative interpretations of the variation of radial velocity across these knots, such as a variation in the jet orientation, as well as for the velocity asymmetries between the flows, are also considered. The presence of a correlation between flow velocity and collimation in each flow is suggested.Comment: Accepted for publication in Astronomy and Astrophysics, 16 page

Two-Level Systems in Nucleated and Non-Nucleated Epitaxial alpha-Tantalum films

Building usefully coherent superconducting quantum processors depends on reducing losses in their constituent materials. Tantalum, like niobium, has proven utility as the primary superconducting layer within highly coherent qubits. But, unlike Nb, high temperatures are typically used to stabilize the desirable body-centered-cubic phase, alpha-Ta, during thin film deposition. It has long been known that a thin Nb layer permits the room-temperature nucleation of alpha-Ta, although neither an epitaxial process nor few-photon microwave loss measurements have been reported for Nb-nucleated Ta films prior to this study. We compare resonators patterned from Ta films grown at high temperature (500 {\deg}C) and films nucleated at room temperature, in order to understand the impact of crystalline order on quantum coherence. In both cases, films grew with Al2O3 (001) || Ta (110) indicating that the epitaxial orientation is independent of temperature and is preserved across the Nb/Ta interface. We use conventional low-power spectroscopy to measure two level system (TLS) loss, as well as an electric-field bias technique to measure the effective dipole moments of TLS in the surfaces of resonators. In our measurements, Nb-nucleated Ta resonators had greater loss tangent (1.5 +/- 0.1 x 10^-5) than non-nucleated (5 +/- 1 x 10^-6) in approximate proportion to defect densities as characterized by X-ray diffraction (0.27 {\deg} vs 0.18 {\deg} [110] reflection width) and electron microscopy (30 nm vs 70 nm domain size). The dependence of the loss tangent on domain size indicates that the development of more ordered Ta films is likely to lead to improvements in qubit coherence times. Moreover, low-temperature alpha-Ta epitaxy may enable the growth of new, microstate-free heterostructures which would not withstand high temperature processing

Global embeddings of scalar-tensor theories in (2+1)-dimensions

We obtain (3+3)- or (3+2)-dimensional global flat embeddings of four uncharged and charged scalar-tensor theories with the parameters B or L in the (2+1)-dimensions, which are the non-trivially modified versions of the Banados-Teitelboim-Zanelli (BTZ) black holes. The limiting cases B=0 or L=0 exactly are reduced to the Global Embedding Minkowski Space (GEMS) solution of the BTZ black holes.Comment: 19 pages, 2 figure

Comparative Study Of High Temperature Workability OF ZM21 And AZ31 Magnesium Alloys

High temperature regime, 300-450?C for Mg-Al-Zn alloys, is currently used in primary processing, such as rolling and extrusion, as well as for secondary operation like forging. The knowledge of temperature and strain rate proper combination (processing window) as well as the microstructure evolution occurring during hot deformation clarifies the relationships between forming variables and final properties of components. Numerous data on AZ31 and few other Mg-Al alloys, produced by laboratory testing, are available in the scientific and technical literature. The ZM21, Mg-2Zn-1Mn, by contrast, is characterized by absolute lack of scientific data. In the alloy the addition of manganese, by suppressing the formation of beta phase, increases the solidus temperature that results in the larger processing window than in AZ31. The benefit requires extensive analysis aimed at optimizing the deformation variables that affect the microstructure refinement under dynamic and static recrystallization. The high-temperature plastic deformation and the microstructure evolution of the ZM21 were thus investigated in the temperature range between 200 and 500?C and results were analysed and compared with those of a conventional heat-treated AZ31