Detection of radio emission from stars via proper-motion searches

We present a method for identifying radio stellar sources using their proper-motion. We demonstrate this method using the FIRST, VLASS, RACS-low and RACS-mid radio surveys, and astrometric information from Gaia Data Release 3. We find eight stellar radio sources using this method, two of which have not previously been identified in the literature as radio stars. We determine that this method probes distances of ~90pc when we use FIRST and RACS-mid, and ~250pc when we use FIRST and VLASS. We investigate the time baselines required by current and future radio sky surveys to detect the eight sources we found, with the SKA (6.7 GHz) requiring <3 years between observations to find all eight sources. We also identify nine previously known and 43 candidate variable radio stellar sources that are detected in FIRST (1.4 GHz) but are not detected in RACS-mid (1.37 GHz). This shows that many stellar radio sources are variable, and that surveys with multiple epochs can detect a more complete sample of stellar radio sources.Comment: 20 pages, 6 figures, 6 tables, accepted for publication in PAS

Data Mesh: a Systematic Gray Literature Review

Data mesh is an emerging domain-driven decentralized data architecture that aims to minimize or avoid operational bottlenecks associated with centralized, monolithic data architectures in enterprises. The topic has picked the practitioners' interest, and there is considerable gray literature on it. At the same time, we observe a lack of academic attempts at defining and building upon the concept. Hence, in this article, we aim to start from the foundations and characterize the data mesh architecture regarding its design principles, architectural components, capabilities, and organizational roles. We systematically collected, analyzed, and synthesized 114 industrial gray literature articles. The review provides insights into practitioners' perspectives on the four key principles of data mesh: data as a product, domain ownership of data, self-serve data platform, and federated computational governance. Moreover, due to the comparability of data mesh and SOA (service-oriented architecture), we mapped the findings from the gray literature into the reference architectures from the SOA academic literature to create the reference architectures for describing three key dimensions of data mesh: organization of capabilities and roles, development, and runtime. Finally, we discuss open research issues in data mesh, partially based on the findings from the gray literature

Periodic Radio Emission from the T8 Dwarf WISE J062309.94-045624.6

We present the detection of rotationally modulated, circularly polarized radio emission from the T8 brown dwarf WISE J062309.94-045624.6 between 0.9 and 2.0 GHz. We detected this high proper motion ultracool dwarf with the Australian SKA Pathfinder in $1.36$ GHz imaging data from the Rapid ASKAP Continuum Survey. We observed WISE J062309.94-045624.6 to have a time and frequency averaged Stokes I flux density of $4.17\pm0.41$ mJy beam$^{-1}$, with an absolute circular polarization fraction of $66.3\pm9.0\%$, and calculated a specific radio luminosity of $L_{\nu}\sim10^{14.8}$ erg s$^{-1}$ Hz$^{-1}$. In follow-up observations with the Australian Telescope Compact Array and MeerKAT we identified a multi-peaked pulse structure, used dynamic spectra to place a lower limit of $B>0.71$ kG on the dwarf's magnetic field, and measured a $P=1.912\pm0.005$ h periodicity which we concluded to be due to rotational modulation. The luminosity and period we measured are comparable to those of other ultracool dwarfs observed at radio wavelengths. This implies that future megahertz to gigahertz surveys, with increased cadence and improved sensitivity, are likely to detect similar or later-type dwarfs. Our detection of WISE J062309.94-045624.6 makes this dwarf the coolest and latest-type star observed to produce radio emission.Comment: Accepted for publication in ApJ Letters; 11 pages, 3 figures and 2 table

Helicobacter suis Causes Severe Gastric Pathology in Mouse and Mongolian Gerbil Models of Human Gastric Disease

Background: “Helicobacter (H.) heilmannii” type 1 is the most prevalent gastric non-H. pylori Helicobacter species in humans suffering from gastric disease. It has been shown to be identical to H. suis, a bacterium which is mainly associated with pigs. To obtain better insights into the long-term pathogenesis of infections with this micro-organism, experimental infections were carried out in different rodent models. Methodology/Principal findings: Mongolian gerbils and mice of two strains (BALB/c and C57BL/6) were infected with H. suis and sacrificed at 3 weeks, 9 weeks and 8 months after infection. Gastric tissue samples were collected for PCR analysis, histological and ultrastructural examination. In gerbils, bacteria mainly colonized the antrum and a narrow zone in the fundus near the forestomach/stomach transition zone. In both mice strains, bacteria colonized the entire glandular stomach. Colonization with H. suis was associated with necrosis of parietal cells in all three animal strains. From 9 weeks after infection onwards, an increased proliferation rate of mucosal epithelial cells was detected in the stomach regions colonized with H. suis. Most gerbils showed a marked lymphocytic infiltration in the antrum and in the forestomach/stomach transition zone, becoming more pronounced in the course of time. At 8 months post infection, severe destruction of the normal antral architecture at the inflamed sites and development of mucosa-associated lymphoid tissue (MALT) lymphoma-like lesions were observed in some gerbils. In mice, the inflammatory response was less pronounced than in gerbils, consisting mainly of mononuclear cell infiltration and being most severe in the fundus. Conclusions/Significance: H. suis causes death of parietal cells, epithelial cell hyperproliferation and severe inflammation in mice and Mongolian gerbil models of human gastric disease. Moreover, MALT lymphoma-like lesions were induced in H. suis-infected Mongolian gerbils. Therefore, the possible involvement of this micro-organism in human gastric disease should not be neglected

Generation of proton-motive force by an archaeal terminal quinol oxidase from Sulfolobus acidocaldarius

The terminal quinol oxidase of the cytochrome aa3 type was isolated from the extreme thermo-acidophilic archaeon Sulfolobus acidocaldarius. In micellar solution, the enzyme oxidized various quinols and exerted the highest activity with the physiological substrate caldariella quinol. The enzyme was functionally reconstituted into monolayer liposomes composed of archaeal tetraether lipids also derived from S. acidocaldarius. With the electron donor system ascorbate and N,N,N',N'-tetramethyl-p-phenylenediamine, the reconstituted enzyme was more active in the archaeal lipids as compared to lipids derived from Escherichia coli at temperatures above 50°C. Due to the low proton permeability of the tetraether lipids, it was possible to generate a steady-state transmembrane electrical potential (ΔΨ, interior negative), and transmembrane pH gradient (ΔpH, interior alkaline) at temperatures up to 70°C. The successful functional reconstitution of the cytochrome aa3-type quinol oxidase from Sulfolobus identifies it as the key energy converter in the respiratory system of this hyperthermophilic archaeon

A global survey of health care workers' awareness of non-alcoholic fatty liver disease:The AwareNASH survey

Background: The estimated global prevalence and burden of non-alcoholic fatty liver disease (NAFLD) and its advanced stage, non-alcoholic steatohepatitis (NASH), is increasing. Yet, NAFLD remains largely underdiagnosed. In addition to hepatic morbidity and mortality, NAFLD is associated with increased cardiovascular complications, warranting a multidisciplinary approach. Despite its rapidly increasing prevalence, knowledge of NAFLD among healthcare workers is limited, especially with specialists outside the field of hepatology and gastroenterology. Objectives: To investigate knowledge, practice and opinions/attitudes of healthcare workers towards diagnosis and management of NAFLD/NASH. Methods: The survey was designed in collaboration with a multidisciplinary scientific committee established especially for this study. The survey was disseminated to healthcare workers from seven different disciplines through four collaborating societies, social media and at a cardiology-themed conference from February to June 2022. Median and interquartile range were mentioned for numeric responses and proportions for categorical responses or responses on a Likert scale. Likert scale responses were treated as ordinal data and analysed with the appropriate tests. Results: The full dataset included 613 respondents from 88 different countries (including 488 physicians). 64% of the surveyed physicians underestimated the prevalence of NAFLD. General practitioners and cardiologists underestimated the prevalence most often (74% and 77%, respectively). Compared to the other disciplines, cardiologists were least familiar with the symptoms and diagnostic criteria and felt least confident in diagnosing and managing NAFLD. Overall, 65% of physicians reported regularly using evidence-based guidelines for managing NAFLD, yet 72% reported challenges in providing lifestyle recommendations. A lack of awareness was the most common reported reason for the lack of screening for NAFLD (68% respectively). Conclusions: Despite the growing burden of NAFLD, there is a significant gap in awareness, knowledge, and management among physicians treating patients with cardiometabolic comorbidities, particularly cardiologists. Hepatologists and gastroenterologists could play a role in educating their fellow physicians.</p