Sterilizable photomultiplier tubes Final report

Environment, static acceleration, vibration, shock, gas contamination, and life tests in development of sterilizable photomultipliers for space program

Improved sterilizable multiplier phototubes Final report

Development of sterilizable multiplier phototube for scintillation counte

Is the way we're dieting wrong?

Progress in personalized medicine is now being translated to personalized nutrition. A recent proof-of-concept study shows that the increase in blood glucose levels after a meal is highly variable between individuals, but can be predicted by using a computational model that combines information from gut microbiome profiles and dietary questionnaires. This study raises questions about the usefulness of universal diet recommendations, and suggests we might need to move on to personalized diets

Extreme AO Observations of Two Triple Asteroid Systems with SPHERE

We present the discovery of a new satellite of asteroid (130) Elektra - S/2014 (130) 1 - in differential imaging and in integral field spectroscopy data over multiple epochs obtained with SPHERE/VLT. This new (second) moonlet of Elektra is about 2 km across, on an eccentric orbit and about 500 km away from the primary. For a comparative study, we also observed another triple asteroid system (93) Minerva. For both systems, component-resolved reflectance spectra of the satellites and primary were obtained simultaneously. No significant spectral difference was observed between the satellites and the primary for either triple system. We find that the moonlets in both systems are more likely to have been created by sub-disruptive impacts as opposed to having been captured.Comment: 8 pages, 4 figures, 1 table, accepted to be published in the Astrophysical Journal Letter

Reduction of trimethylamine N-oxide to trimethylamine by the human gut microbiota: supporting evidence for ‘metabolic retroversion’

Dietary sources of methylamines such as choline, trimethylamine (TMA), trimethylamine N-oxide (TMAO), phosphatidylcholine (PC) and carnitine are present in a number of foodstuffs, including meat, fish, nuts and eggs. It is recognized that the gut microbiota is able to convert choline to TMA in a fermentation-like process. Similarly, PC and carnitine are converted to TMA by the gut microbiota. It has been suggested that TMAO is subject to ‘metabolic retroversion’ in the gut (i.e. it is reduced to TMA by the gut microbiota, with this TMA being oxidized to produce TMAO in the liver). Sixty-six strains of human faecal and caecal bacteria were screened on solid and liquid media for their ability to utilize trimethylamine N-oxide (TMAO), with metabolites in spent media profiled by Proton Nuclear Magnetic Resonance (1H NMR) spectroscopy. Enterobacteriaceae produced mostly TMA from TMAO, with caecal/small intestinal isolates of Escherichia coli producing more TMA than their faecal counterparts. Lactic acid bacteria (enterococci, streptococci, bifidobacteria) produced increased amounts of lactate when grown in the presence of TMAO, but did not produce large amounts of TMA from TMAO. The presence of TMAO in media increased the growth rate of Enterobacteriaceae; while it did not affect the growth rate of lactic acid bacteria, TMAO increased the biomass of these bacteria. The positive influence of TMAO on Enterobacteriaceae was confirmed in anaerobic, stirred, pH-controlled batch culture fermentation systems inoculated with human faeces, where this was the only bacterial population whose growth was significantly stimulated by the presence of TMAO in the medium. We hypothesize that dietary TMAO is used as an alternative electron acceptor by the gut microbiota in the small intestine/proximal colon, and contributes to microbial population dynamics upon its utilization and retroversion to TMA, prior to absorption and secondary conversion to TMAO by hepatic flavin-containing monooxygenases. Our findings support the idea that oral TMAO supplementation is a physiologically-stable microbiota-mediated strategy to deliver TMA at the gut barrier

Lockdown, bottoms up? Changes in adolescent substance use across the COVID-19 pandemic

The COVID-19 pandemic notably altered adolescent substance use during the initial stage (Spring 2020) of the pandemic. The purpose of this longitudinal study is to examine trajectories of adolescent substance use across the pandemic and subsequent periods of stay-at-home orders and re-opening efforts. We further examined differences as a function of current high school student versus graduate status. Adolescents (n = 1068, 14–18 years, Mage = 16.95 years and 76.7% female at T1) completed 4 different self-report surveys, starting during the first stay-at-home order and ending approximately 14 months later. Negative binomial hurdle models predicted: (1) the likelihood of no substance use and (2) frequency of days of substance use. As hypothesized, results demonstrated significant increases in adolescents’ likelihood of alcohol use, binge drinking, and cannabis use once initial stay-at-home orders were lifted, yet few changes occurred as a result of a second stay-at-home order, with rates never lowering again to that of the first lockdown. Further, graduates (and particularly those who transitioned out of high school during the study) demonstrated a greater likelihood and frequency of substance use and were more stable in their trajectories across periods of stay-at-home orders than current high school students. Unexpectedly, however, there was a strong increase in current high school students’ likelihood of e-cigarette use and a significant linear increase in participants’ frequency of e-cigarette use over the study. Results suggest adolescent substance use, and in particular, e-cigarette use among current high school students, may be of increasing concern as the pandemic evolves

Unfolding-Based Process Discovery

This paper presents a novel technique for process discovery. In contrast to the current trend, which only considers an event log for discovering a process model, we assume two additional inputs: an independence relation on the set of logged activities, and a collection of negative traces. After deriving an intermediate net unfolding from them, we perform a controlled folding giving rise to a Petri net which contains both the input log and all independence-equivalent traces arising from it. Remarkably, the derived Petri net cannot execute any trace from the negative collection. The entire chain of transformations is fully automated. A tool has been developed and experimental results are provided that witness the significance of the contribution of this paper.Comment: This is the unabridged version of a paper with the same title appearead at the proceedings of ATVA 201