Characteristics of academic publications, preprints, and registered clinical trials on the COVID-19 pandemic

The COVID-19 pandemic has unleashed a deluge of publications. For this cross-sectional study we compared the amount and reporting characteristics of COVID-19-related academic articles and preprints and the number of ongoing clinical trials and systematic reviews. To do this, we searched the PubMed database of citations and abstracts for published life science journals by using appropriate combinations of medical subject headings (MeSH terms), and the COVID-19 section of the MedRxiv and BioRxiv archives up to 20 May 2020 (21 weeks). In addition, we searched Clinicaltrial.gov, Chinese Clinical Trial Registry, EU Clinical Trials Register, and 15 other trial registers, as well as PROSPERO, the international prospective register of systematic reviews. The characteristics of each publication were extracted. Regression analyses and Z tests were used to detect publication trends and their relative proportions. A total of 3635 academic publications and 3805 preprints were retrieved. Only 8.6% (n = 329) of the preprints were already published in indexed journals. The number of academic and preprint publications increased significantly over time (p<0.001). Case reports (6% academic vs 0.9% preprints; p<0.001) and letters (17.4% academic vs 0.5% preprints; p<0.001) accounted for a greater share of academic compared to preprint publications. Differently, randomized controlled trials (0.22% vs 0.63%; p<0.001) and systematic reviews (0.08% vs 5%) made up a greater share of the preprints. The relative proportion of clinical studies registered at Clinicaltrials.gov, Chinese Clinical Trial Registry, and EU Clinical Trials Register was 57.9%, 49.5%, and 98.9%, respectively, most of which were still "recruiting". PROSPERO listed 962 systematic review protocols. Preprints were slightly more prevalent than academic articles but both were increasing in number. The void left by the lack of primary studies was filled by an outpour of immediate opinions (i.e., letters to the editor) published in PubMed-indexed journals. Summarizing, preprints have gained traction as a publishing response to the demand for prompt access to empirical, albeit not peer-reviewed, findings during the present pandemic.publishersversionpublishe

Ultrasmall SnO2 directly grown on commercial carbon black: a versatile composite material for Li-based energy storage

Herein, we propose a hassle-free approach to prepare SnO2/C composite using a simple, fully sustainable, and economic synthesis process, in which tin oxide is in situ nucleated on commercial carbon black C-NERGYTM Super C45 (Imerys Graphite &amp; Carbon) in form of homogenously distributed nanoparticles. The synthesis is carried out by wet impregnation without any acid treatment or high temperature process. We focused on the presence of the existing oxygen species on the carbon surface that are accessible for tin and promote Sn–O–C interactions, suggesting synergies between the two components, with an active role of the carbon support in the SnO2 conversion reaction. On one hand, in Li-ion technology, development of high-performance SnO2 anodes is hampered by its peculiar electrochemical behavior, characterized by two processes: conversion and alloying reactions. The conversion reaction being irreversible leads to specific capacities lower than theoretical, however rational design of nanosized SnO2 can mitigate this issue, though SnO2 low conductivity and electrode pulverization justify the need of carbon matrices. Some carbon structures proved to be strongly effective at laboratory-scale, but most are too expensive or complicated to obtain for scaling-up. Presence of oxygen species on C45 surface, accessible to tin, prevent fast formation of Li2O, allowing to achieve high capacity and extreme electrode stability. The assembled cells with SnO2 /C45 exhibit for more than 400 cycles the reversible capacity of 560 mA h g−1 per pure SnO2 (after subtracting C45 contribution) at 1C, demonstrating prolonged cycling operation thus providing an interesting opportunity for scalable production of stable and high-capacity battery anodes alternatively to graphite [1]. On the other hand, developing efficient and low cost electrocatalysts for ORR is fundamental to bring the Li-O2 technology closer to practical applications. The obtained composite material shows an optimal ORR activity with a final reduction mechanism following the 4 electrons pathway. This is confirmed in Li-O2 cells, indeed compared to pure C45 air-cathodes, the composite cathodes lead to the formation of much more reversible film-like discharge products, allowing for reduced overvoltage and therefore improved cycling performances both at the high current density of 0.5 mA cm-2 with more than 70 cycles and in prolonged discharge/charge conditions with over 1250 h of operation at the fixed capacity of 2.5 mAh cm-2 [2]. Considering the fast and inexpensive method used to prepare SnO2/C45, these results, in terms of reversible capacities and long cycling stability, are competitive among others obtained for SnO2-based materials synthetized by other methods such as hydrothermal, sonochemical, solvothermal, etc. All these considerations make the synthetic route reported a suitable and interesting approach for large scale production. References 1. D

Angiotensin-(1–7) and the G Protein-Coupled Receptor Mas Are Key Players in Renal Inflammation

Angiotensin (Ang) II mediates pathophysiologial changes in the kidney. Ang-(1–7) by interacting with the G protein-coupled receptor Mas may also have important biological activities

Substantial contribution of iodine to Arctic ozone destruction

Unlike bromine, the effect of iodine chemistry on the Arctic surface ozone budget is poorly constrained. We present ship-based measurements of halogen oxides in the high Arctic boundary layer from the sunlit period of March to October 2020 and show that iodine enhances springtime tropospheric ozone depletion. We find that chemical reactions between iodine and ozone are the second highest contributor to ozone loss over the study period, after ozone photolysis-initiated loss and ahead of bromine.Iodine chemistry plays a more important role than bromine chemistry in tropospheric ozone losses in the Arctic, according to ship-based observations of halogen oxides from March to October 2020.Peer reviewe

Measuring health-related quality of life in men with osteoporosis or osteoporotic fracture

<p>Abstract</p> <p>Background</p> <p>Osteoporosis is a serious health problem that worsens the quality of life and the survival rate of individuals with this disease on account the osteoporotic fractures. Studies have long focused on women, and its presence in men has been underestimated. While many studies conducted in different countries mainly assess health-related quality of life and identify fracture risks factors in women, few data are available on a Spanish male population.</p> <p>Methods/Design</p> <p>Observational study.</p> <p>Study population</p> <p>Men ≥ 40 years of age with/without diagnosed osteoporosis and with/without osteoporotic fracture included by their family doctor.</p> <p>Measurements</p> <p>The relationship between customary clinical risk factors for osteoporotic fracture and health-related quality of life in a Spanish male population. A telephone questionnaire on health-related quality of life is made.</p> <p>Statistical analysis</p> <p>The association between qualitative variables will be assessed by the Chi-square test. The distribution of quantitative variables by Student's t-test. If the conditions for using this test are not met, the non-parametric Mann-Whitney's U test will be used.</p> <p>The validation of the results obtained by the FRAX™ tool will be performed by way of the Hosmer-Lemeshow test and by calculating the area under the Receiver Operating Characteristic (ROC) curve (AUC). All tests will be performed with a confidence intervals set at 95%.</p> <p>Discussion</p> <p>The applicability and usefulness of Health-related quality of life (HRQOL) studies are well documented in many countries. These studies allow implementing cost-effective measures in cases of a given disease and reducing the costly consequences derived therefrom. This study attempts to provide objective data on how quality of life is affected by the clinical aspects involved in osteoporosis in a Spanish male population and can be useful as well in cost utility analyses conducted by health authorities.</p> <p>The sample selected is not based on a high fracture risk group. Rather, it is composed of men in the general population, and accordingly comparisons should not lead to erroneous interpretations.</p> <p>A possible bias correction will be ensured by checking reported fractures against healthcare reports and X-rays, or by consulting health care centers as applicable.</p

Measurement of the cosmic ray spectrum above 4×10184{\times}10^{18} eV using inclined events detected with the Pierre Auger Observatory

A measurement of the cosmic-ray spectrum for energies exceeding $4{\times}10^{18}$ eV is presented, which is based on the analysis of showers with zenith angles greater than $60^{\circ}$ detected with the Pierre Auger Observatory between 1 January 2004 and 31 December 2013. The measured spectrum confirms a flux suppression at the highest energies. Above $5.3{\times}10^{18}$ eV, the "ankle", the flux can be described by a power law $E^{-\gamma}$ with index $\gamma=2.70 \pm 0.02 \,\text{(stat)} \pm 0.1\,\text{(sys)}$ followed by a smooth suppression region. For the energy ($E_\text{s}$) at which the spectral flux has fallen to one-half of its extrapolated value in the absence of suppression, we find $E_\text{s}=(5.12\pm0.25\,\text{(stat)}^{+1.0}_{-1.2}\,\text{(sys)}){\times}10^{19}$ eV.Comment: Replaced with published version. Added journal reference and DO

Energy Estimation of Cosmic Rays with the Engineering Radio Array of the Pierre Auger Observatory

The Auger Engineering Radio Array (AERA) is part of the Pierre Auger Observatory and is used to detect the radio emission of cosmic-ray air showers. These observations are compared to the data of the surface detector stations of the Observatory, which provide well-calibrated information on the cosmic-ray energies and arrival directions. The response of the radio stations in the 30 to 80 MHz regime has been thoroughly calibrated to enable the reconstruction of the incoming electric field. For the latter, the energy deposit per area is determined from the radio pulses at each observer position and is interpolated using a two-dimensional function that takes into account signal asymmetries due to interference between the geomagnetic and charge-excess emission components. The spatial integral over the signal distribution gives a direct measurement of the energy transferred from the primary cosmic ray into radio emission in the AERA frequency range. We measure 15.8 MeV of radiation energy for a 1 EeV air shower arriving perpendicularly to the geomagnetic field. This radiation energy -- corrected for geometrical effects -- is used as a cosmic-ray energy estimator. Performing an absolute energy calibration against the surface-detector information, we observe that this radio-energy estimator scales quadratically with the cosmic-ray energy as expected for coherent emission. We find an energy resolution of the radio reconstruction of 22% for the data set and 17% for a high-quality subset containing only events with at least five radio stations with signal.Comment: Replaced with published version. Added journal reference and DO

Measurement of the Radiation Energy in the Radio Signal of Extensive Air Showers as a Universal Estimator of Cosmic-Ray Energy

We measure the energy emitted by extensive air showers in the form of radio emission in the frequency range from 30 to 80 MHz. Exploiting the accurate energy scale of the Pierre Auger Observatory, we obtain a radiation energy of 15.8 \pm 0.7 (stat) \pm 6.7 (sys) MeV for cosmic rays with an energy of 1 EeV arriving perpendicularly to a geomagnetic field of 0.24 G, scaling quadratically with the cosmic-ray energy. A comparison with predictions from state-of-the-art first-principle calculations shows agreement with our measurement. The radiation energy provides direct access to the calorimetric energy in the electromagnetic cascade of extensive air showers. Comparison with our result thus allows the direct calibration of any cosmic-ray radio detector against the well-established energy scale of the Pierre Auger Observatory.Comment: Replaced with published version. Added journal reference and DOI. Supplemental material in the ancillary file