The CO A-X System for Constraining Cosmological Drift of the Proton-Electron Mass Ratio

The $\textrm{A}^1\Pi-\textrm{X}^1\Sigma^+$ band system of carbon monoxide, which has been detected in six highly redshifted galaxies ($z=1.6-2.7$), is identified as a novel probe method to search for possible variations of the proton-electron mass ratio ($\mu$) on cosmological time scales. Laboratory wavelengths of the spectral lines of the A-X ($v$,0) bands for $v=0-9$ have been determined at an accuracy of $\Delta\lambda/\lambda=1.5 \times 10^{-7}$ through VUV Fourier-transform absorption spectroscopy, providing a comprehensive and accurate zero-redshift data set. For the (0,0) and (1,0) bands, two-photon Doppler-free laser spectroscopy has been applied at the $3 \times 10^{-8}$ accuracy level, verifying the absorption data. Sensitivity coefficients $K_{\mu}$ for a varying $\mu$ have been calculated for the CO A-X bands, so that an operational method results to search for $\mu$-variation.Comment: 7 pages (main article), 3 figures, includes supplementary materia

Robust Constraint on a Drifting Proton-to-Electron Mass Ratio at z=0.89 from Methanol Observation at Three Radio Telescopes

A limit on a possible cosmological variation of the proton-to-electron mass ratio $\mu$ is derived from methanol (CH$_3$OH) absorption lines in the benchmark PKS1830$-$211 lensing galaxy at redshift $z = 0.89$ observed with the Effelsberg 100-m radio telescope, the Institute de Radio Astronomie Millim\'{e}trique 30-m telescope, and the Atacama Large Millimeter/submillimeter Array. Ten different absorption lines of CH$_3$OH covering a wide range of sensitivity coefficients $K_{\mu}$ are used to derive a purely statistical 1-$\sigma$ constraint of $\Delta\mu/\mu = (1.5 \pm 1.5) \times 10^{-7}$ for a lookback time of 7.5 billion years. Systematic effects of chemical segregation, excitation temperature, frequency dependence and time variability of the background source are quantified. A multi-dimensional linear regression analysis leads to a robust constraint of $\Delta\mu/\mu = (-1.0 \pm 0.8_{\rm stat} \pm 1.0_{\rm sys}) \times 10^{-7}$.Comment: 5 pages, 3 figures. Published in PR

A stringent limit on a drifting proton-to-electron mass ratio from alcohol in the early Universe

The standard model of physics is built on the fundamental constants of nature, but it does not provide an explanation for their values, nor requires their constancy over space and time. Here, we set a limit on a possible cosmological variation of the proton-to-electron mass ratio μ by comparing transitions in methanol observed in the early universe with those measured in the laboratory. Based on radio-astronomical observations of PKS1830-211, we deduced a constraint of ∆μ/μ = (0.0 ± 1.0) × 10−7 at redshift z = 0.89, corresponding to a look-back time of 7 billion years. This is consistent with a null result

The Hyperlipidaemic Drug Fenofibrate Significantly Reduces Infection by SARS-CoV-2 in Cell Culture Models

The severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) pandemic has caused a significant number of fatalities and worldwide disruption. To identify drugs to repurpose to treat SARS-CoV-2 infections, we established a screen to measure the dimerization of angiotensin-converting enzyme 2 (ACE2), the primary receptor for the virus. This screen identified fenofibric acid, the active metabolite of fenofibrate. Fenofibric acid also destabilized the receptor-binding domain (RBD) of the viral spike protein and inhibited RBD binding to ACE2 in enzyme-linked immunosorbent assay (ELISA) and whole cell-binding assays. Fenofibrate and fenofibric acid were tested by two independent laboratories measuring infection of cultured Vero cells using two different SARS-CoV-2 isolates. In both settings at drug concentrations, which are clinically achievable, fenofibrate and fenofibric acid reduced viral infection by up to 70%. Together with its extensive history of clinical use and its relatively good safety profile, this study identifies fenofibrate as a potential therapeutic agent requiring an urgent clinical evaluation to treat SARS-CoV-2 infection

Dietary acrylamide intake and risk of breast cancer in the UK women's cohort

No studies to date have demonstrated a clear association with breast cancer risk and dietary exposure to acrylamide.Methods:A 217-item food frequency questionnaire was used to estimate dietary acrylamide intake in 33,731 women aged 35-69 years from the UK Women's Cohort Study followed up for a median of 11 years

ARDD 2020: from aging mechanisms to interventions

Aging is emerging as a druggable target with growing interest from academia, industry and investors. New technologies such as artificial intelligence and advanced screening techniques, as well as a strong influence from the industry sector may lead to novel discoveries to treat age-related diseases. The present review summarizes presentations from the 7th Annual Aging Research and Drug Discovery (ARDD) meeting, held online on the 1st to 4th of September 2020. The meeting covered topics related to new methodologies to study aging, knowledge about basic mechanisms of longevity, latest interventional strategies to target the aging process as well as discussions about the impact of aging research on society and economy. More than 2000 participants and 65 speakers joined the meeting and we already look forward to an even larger meeting next year. Please mark your calendars for the 8th ARDD meeting that is scheduled for the 31st of August to 3rd of September, 2021, at Columbia University, USA

Variation in contents of hypericin and flavonoids in Hypericum maculatum (Hypericaceae) from Lithuania

This study, carried out in 2004–2005, describes the variation of hypericin and flavonoid contents in different samples of Hypericum maculatum . Flowering tops of H. maculatum were collected and analysed for hypericin and flavonoids using HPLC. The contents of hypericin ranged from 0.35–0.95 mg/g; flavonoid contents varied as follows: hyperoside — 16.66–40.89 mg/g, quercitrin — 0.00 to 1.07 mg/g and quercetin — 1.46–4.96 mg/g. The study indicated that flavonoid rutin was absent from the flavonoid pattern of H. maculatum , or present only in trace amounts (0.00–0.67 mg/g), however, H. maculatum is one of the most important sources of hyperoside. The samples of H. maculatum which accumulated high levels of flavonoids seem to be promising for further propagation