GW170817 was the first gravitational-wave detection of a binary neutron-star merger. It was accompanied by radiation across the electromagnetic spectrum and localized to the galaxy NGC 4993 at a ...distance of 40 megaparsecs. It has been proposed that the observed γ-ray, X-ray and radio emission is due to an ultra-relativistic jet being launched during the merger (and successfully breaking out of the surrounding material), directed away from our line of sight (off-axis). The presence of such a jet is predicted from models that posit neutron-star mergers as the drivers of short hard-γ-ray bursts. Here we report that the radio light curve of GW170817 has no direct signature of the afterglow of an off-axis jet. Although we cannot completely rule out the existence of a jet directed away from the line of sight, the observed γ-ray emission could not have originated from such a jet. Instead, the radio data require the existence of a mildly relativistic wide-angle outflow moving towards us. This outflow could be the high-velocity tail of the neutron-rich material that was ejected dynamically during the merger, or a cocoon of material that breaks out when a jet launched during the merger transfers its energy to the dynamical ejecta. Because the cocoon model explains the radio light curve of GW170817, as well as the γ-ray and X-ray emission (and possibly also the ultraviolet and optical emission), it is the model that is most consistent with the observational data. Cocoons may be a ubiquitous phenomenon produced in neutron-star mergers, giving rise to a hitherto unidentified population of radio, ultraviolet, X-ray and γ-ray transients in the local Universe.
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KISLJ, NUK, SBMB, UL, UM, UPUK
Gravitational waves have been detected from a binary neutron star merger event, GW170817. The detection of electromagnetic radiation from the same source has shown that the merger occurred in the ...outskirts of the galaxy NGC 4993, at a distance of 40 megaparsecs from Earth. We report the detection of a counterpart radio source that appears 16 days after the event, allowing us to diagnose the energetics and environment of the merger. The observed radio emission can be explained by either a collimated ultrarelativistic jet, viewed off-axis, or a cocoon of mildly relativistic ejecta. Within 100 days of the merger, the radio light curves will enable observers to distinguish between these models, and the angular velocity and geometry of the debris will be directly measurable by very long baseline interferometry.
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BFBNIB, NMLJ, NUK, ODKLJ, PNG, SAZU, UL, UM, UPUK
Hydrothermal reduction is a promising approach for graphene oxide (GO) reduction since it is environmentally friendly, simple, and cost effective. We present a detailed study of structural changes ...occurring in graphene oxide during the reduction process. The correlations between the interlayer spacing, chemical states, work functions, surface morphology, level of disorders, the number of layers, and processing time are elucidated. The results reveal that GO flakes remain in the early stage of the reduction process and that they are fully reduced after a 4-h hydrothermal treatment. With an increase in the reduction time, the resulting product, i.e., reduced graphene oxide, has a low oxygen content, small interlayer spacing, and crumbled and wrinkled structures. We are convinced that these properties can be tuned to a desired level for various applications.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Nuclear magnetic resonance spectroscopy is a powerful tool for the structural analysis of organic compounds and biomolecules but typically requires macroscopic sample quantities. We use a sensor, ...which consists of two quantum bits corresponding to an electronic spin and an ancillary nuclear spin, to demonstrate room temperature magnetic resonance detection and spectroscopy of multiple nuclear species within individual ubiquitin proteins attached to the diamond surface. Using quantum logic to improve readout fidelity and a surface-treatment technique to extend the spin coherence time of shallow nitrogen-vacancy centers, we demonstrate magnetic field sensitivity sufficient to detect individual proton spins within 1 second of integration. This gain in sensitivity enables high-confidence detection of individual proteins and allows us to observe spectral features that reveal information about their chemical composition.
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BFBNIB, NMLJ, NUK, ODKLJ, PNG, SAZU, UL, UM, UPUK
Oteseconazole was approved by the US FDA in April 2022. It is the first approved selective and orally bioavailable CYP51 inhibitor for the treatment of patients with recurrent Vulvovaginal ...candidiasis. Herein, we describe its dosage, administration, chemical structure, physical properties, synthesis, mechanism of action, and pharmacokinetics.
Atopic dermatitis is epidermal hyperplasia, skin barrier dysfunction, and the aberrant activation of immune cells. Janus kinase (JAK) is a family of cytoplasmic nonreceptor tyrosine kinases that ...consists of four members, such as JAK1, JAK2, JAK3, and TYK2. The JAK signaling pathway plays a critical role in a wide range of autoimmune and inflammatory diseases, including atopic dermatitis. Abrocitinib is an orally bioavailable and selective JAK1 inhibitor, and it was approved in January, 2022, for the treatment of atopic dermatitis. The chemical structure and physical properties of abrocitinib, its synthesis, mechanism of action, and pharmacokinetic profile are summarized.
COVID-19 is a contagious disease. Paxlovid, a combination of Nirmatrelvir and Ritonavir, was granted emergency use authorization by the United States Food and Drug Administration (FDA) for the ...treatment of COVID-19 on December 22, 2021. These are peptidomimetic coronavirus main protease inhibitors. Nirmatrelvir is a proline derivative. The present patent describes similar proline- like compounds, their preparation, use, pharmaceutical composition, and treatment.
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