Simple Sorting Criteria Help Find the Causal Order in Additive Noise Models

Additive Noise Models (ANM) encode a popular functional assumption that enables learning causal structure from observational data. Due to a lack of real-world data meeting the assumptions, synthetic ANM data are often used to evaluate causal discovery algorithms. Reisach et al. (2021) show that, for common simulation parameters, a variable ordering by increasing variance is closely aligned with a causal order and introduce var-sortability to quantify the alignment. Here, we show that not only variance, but also the fraction of a variable's variance explained by all others, as captured by the coefficient of determination $R^2$, tends to increase along the causal order. Simple baseline algorithms can use $R^2$-sortability to match the performance of established methods. Since $R^2$-sortability is invariant under data rescaling, these algorithms perform equally well on standardized or rescaled data, addressing a key limitation of algorithms exploiting var-sortability. We characterize and empirically assess $R^2$-sortability for different simulation parameters. We show that all simulation parameters can affect $R^2$-sortability and must be chosen deliberately to control the difficulty of the causal discovery task and the real-world plausibility of the simulated data. We provide an implementation of the sortability measures and sortability-based algorithms in our library CausalDisco (https://github.com/CausalDisco/CausalDisco).Comment: See https://github.com/CausalDisco/CausalDisco for implementation

Gestational Diabetes Mellitus Upsets the Proportion of Fatty Acids in Umbilical Arterial but Not Venous Plasma

OBJECTIVE—Neonates of women with gestational diabetes mellitus (GDM) have reduced levels of arachidonic acid (AA) (20:4 n-6) and docosahexaenoic acid (DHA) (22:6 n-3). To assess whether this is the result of impaired placental transfer or endogenous fetal metabolism, fatty acids in umbilical venous and arterial plasma were analyzed in neonates of GDM women

Review of progress in implementing the recommendations of Sir Gareth Roberts, regarding employability and career development of PhD students and research staff

The need for improvement in the development of research careers and researchers’ training in transferable skills was highlighted in two particular recommendations (numbers 4.2 and 5.3) in the 2002 report ‘SET for success: the report of Sir Gareth Roberts’ Review - the supply of people with science, technology, engineering and mathematics skills’ (Roberts, 2002). As a consequence of that review, Research Councils UK (RCUK)1 have invested about £120 million, usually referred to as ’Roberts’ Money’, in research organisations to address this concern in all research disciplines. The last ‘Roberts’ Money’ payment will be for the period up to March 2011; it was therefore proposed to assess the progress made with taking forward these specific recommendations. An independent panel was formed by RCUK to undertake this review in 2010. The terms of reference for the panel are in Annex A. In summary, the panel was asked to review progress made and to advise RCUK and the higher education (HE) sector about future requirements for the development and training of researchers. In the course of their review, the panel considered a wide range of existing reports, interviewed key stakeholders in the HE sector and elsewhere, as well as drawing on their own knowledge and expertise. This report presents the findings of the panel’s review

Sensing of Dietary Lipids by Enterocytes: A New Role for SR-BI/CLA-1

BACKGROUND: The intestine is responsible for absorbing dietary lipids and delivering them to the organism as triglyceride-rich lipoproteins (TRL). It is important to determine how this process is regulated in enterocytes, the absorptive cells of the intestine, as prolonged postprandial hypertriglyceridemia is a known risk factor for atherosclerosis. During the postprandial period, dietary lipids, mostly triglycerides (TG) hydrolyzed by pancreatic enzymes, are combined with bile products and reach the apical membrane of enterocytes as postprandial micelles (PPM). Our aim was to determine whether these micelles induce, in enterocytes, specific early cell signaling events that could control the processes leading to TRL secretion. METHODOLOGY/PRINCIPAL FINDINGS: The effects of supplying PPM to the apex of Caco-2/TC7 enterocytes were analyzed. Micelles devoid of TG hydrolysis products, like those present in the intestinal lumen in the interprandial period, were used as controls. The apical delivery of PPM specifically induced a number of cellular events that are not induced by interprandial micelles. These early events included the trafficking of apolipoprotein B, a structural component of TRL, from apical towards secretory domains, and the rapid, dose-dependent activation of ERK and p38MAPK. PPM supply induced the scavenger receptor SR-BI/CLA-1 to cluster at the apical brush border membrane and to move from non-raft to raft domains. Competition, inhibition or knockdown of SR-BI/CLA-1 impaired the PPM-dependent apoB trafficking and ERK activation. CONCLUSIONS/SIGNIFICANCE: These results are the first evidence that enterocytes specifically sense postprandial dietary lipid-containing micelles. SR-BI/CLA-1 is involved in this process and could be a target for further study with a view to modifying intestinal TRL secretion early in the control pathway

The effect of extended post-mortem ageing on the Warner–Brazler shear force of longissimus thoracis from beef heifers from two sire breeds, slaughtered at 20 or 25 mo of age

peer-reviewedwere examined. Spring-born Angus × Holstein-Friesian heifers (n = 48) and Belgian Blue × Holstein-Friesian heifers (n = 48) were slaughtered, within sire breed, at 20 or 25 mo of age. Approximately 48 h post-mortem, LT steaks (2.5 cm) were removed, and either stored at −20°C for chemical analysis or vacuum-packed, stored at 2°C for 7, 14 or 28 d post-mortem and then at −20°C pending Warner–Bratzler shear force (WBSF) analysis. Muscle from Angus-sired heifers had higher (P < 0.001) intramuscular fat (IMF) concentration, lower (P < 0.001) proportion of type IIX muscle fibres and higher (P < 0.001) proportion of type IIA and type I muscle fibres compared to muscle from Belgian Blue-sired heifers. Collagen characteristics did not differ between sire breeds. Later slaughter increased (P < 0.001) IMF concentration and decreased (P < 0.001) total and insoluble concentrations and collagen solubility. There were no interactions between the main effects for WBSF and no difference between sire breeds. Later slaughter and increasing the duration of ageing decreased (P < 0.05) WBSF. Based on threshold WBSF values in the literature, all samples would be considered tender (<39 N) after 7 d ageing. Untrained consumers are likely to detect the decrease in WBSF from 7 to 14 d ageing but not due to further ageing. Within the production system examined and based on WBSF data, extending LT ageing to 28 d is not necessary to ensure consumer satisfaction

Crise du Covid-19 : le testing et la vaccination à l’aune des rendements décroissants [Covid-19 crisis: testing and vaccination in the light of diminishing returns]

At the time of the assessment of the sanitary measures taken to fight the crisis, we have analysed the testing and vaccination following the grid well known in health economics: the law of diminishing returns. In the first phase, the returns are positive and increasing, the increase in benefits being faster than the increase in costs. In the second phase, returns are still positive but decreasing, with costs increasing faster than benefits. In the third and last phase, the returns become negative, with benefits decreasing despite an increase in costs. Both testing and vaccination, which were very beneficial at the beginning of the crisis, progressively followed a trajectory of diminishing returns with the extension of the measures to wider populations (asymptomatic or young persons), or for example with the emergence of the Omicron variant