Correlations and clustering in the trading of members of the London Stock Exchange

This paper analyzes correlations in patterns of trading of different members of the London Stock Exchange. The collection of strategies associated with a member institution is defined by the sequence of signs of net volume traded by that institution in hour intervals. Using several methods we show that there are significant and persistent correlations between institutions. In addition, the correlations are structured into correlated and anti-correlated groups. Clustering techniques using the correlations as a distance metric reveal a meaningful clustering structure with two groups of institutions trading in opposite directions

The Peter Principle Revisited: A Computational Study

In the late sixties the Canadian psychologist Laurence J. Peter advanced an apparently paradoxical principle, named since then after him, which can be summarized as follows: {\it 'Every new member in a hierarchical organization climbs the hierarchy until he/she reaches his/her level of maximum incompetence'}. Despite its apparent unreasonableness, such a principle would realistically act in any organization where the mechanism of promotion rewards the best members and where the mechanism at their new level in the hierarchical structure does not depend on the competence they had at the previous level, usually because the tasks of the levels are very different to each other. Here we show, by means of agent based simulations, that if the latter two features actually hold in a given model of an organization with a hierarchical structure, then not only is the Peter principle unavoidable, but also it yields in turn a significant reduction of the global efficiency of the organization. Within a game theory-like approach, we explore different promotion strategies and we find, counterintuitively, that in order to avoid such an effect the best ways for improving the efficiency of a given organization are either to promote each time an agent at random or to promote randomly the best and the worst members in terms of competence.Comment: final version published on Physica A, 10 pages, 4 figures, 1 table (for on-line supplementary material see the link: http://www.ct.infn.it/cactus/peter-links.html

Planning Innovative and Engaging Public Meetings

One of the most effective yet challenging aspects to public outreach is hosting public meetings. Effective facilitators know that public meetings extend well beyond a PowerPoint presentation. Plans must be made for large crowds, media interviews, renderings and handouts, and collection of feedback. During this presentation, we will discuss best practices, including federal guidelines, for planning public meetings of all sizes. We will also discuss some innovative approaches to public meetings, such as integrating social media and televising the event

‘There’s no hope for any kind of decent life’: a qualitative study to explore the perspectives of people experiencing homelessness with a recent non-fatal overdose in Scotland

The past ten years has seen a marked increase in the numbers of people experiencing homelessness globally and an associated public health epidemic of drug-related deaths. Drawing from qualitative interviews as part of a wider pilot randomised controlled trial (RCT) conducted in Glasgow, Scotland with National Health Service pharmacists and third sector homeless outreach caseworkers, insights from those with living experience of both homelessness and a recent non-fatal drug overdose will be presented. Twenty people experiencing homelessness with at least one drug overdose in the past six months were interviewed in person, in a homelessness drop in centre or in emergency accommodation between November 2021 and January 2022. Findings from our study indicate that participants’ drug use and overdose risk were exacerbated during the Covid-19 pandemic due to the pervasive availability of illicit drugs for those placed in emergency accommodation, alongside reduced support and access to health and social care services. Additionally, multi-agency stressors such as a lack of autonomy and dehumanising experiences were reported, leading to a significant sense of powerlessness. Furthermore, the necessity of advocacy-based services as critical aspects of support was identified, with importance placed upon dedicated, homelessness staff and access to safe environments

The effects of nitroxyl (HNO) on soluble guanylate cyclase activity: interactions at ferrous heme and cysteine thiols

It has been previously proposed that nitric oxide (NO) is the only biologically relevant nitrogen oxide capable of activating the enzyme soluble guanylate cyclase (sGC). However, recent reports implicate HNO as another possible activator of sGC. Herein, we examine the affect of HNO donors on the activity of purified bovine lung sGC and find that, indeed, HNO is capable of activating this enzyme. Like NO, HNO activation appears to occur via interaction with the regulatory ferrous heme on sGC. Somewhat unexpectedly, HNO does not activate the ferric form of the enzyme. Finally, HNO-mediated cysteine thiol modification appears to also affect enzyme activity leading to inhibition. Thus, sGC activity can be regulated by HNO via interactions at both the regulatory heme and cysteine thiols

Changes in attitudes, beliefs, and experiences related to pregnancy during graduate medical education training from 2005 to 2021

Today, 50% of medical students are women, and residency and fellowship training years overlap with peak times for starting families. The authors describe attitudes toward pregnancy during residency and fellowship and report pregnancy rates and complications for female residents and resident partners across several decades. A web-based survey was emailed to 1,057 residents in 2005 (period 1) and 1,860 residents in 2021 (period 2). Anonymous surveys were sent to all trainees including pregnant trainees, affected co-trainees and trainee partners. Resident attitudes and pregnancy characteristics were compared between groups using the chi-square (χ2) test for categorical variables and the Kruskal-Wallis test for ordinal variables. A total of 442 residents (41.8%) responded to the 2005 survey, and 525 (28.2%) responded to the 2021 survey. Most residents who covered for a pregnant resident had positive feelings about covering for their colleagues during both time periods, although more positive attitudes were present during the period 2. Only about 10% of residents received compensation for their coverage during both time periods. Among residents with a pregnancy during training (i.e., themselves or partners), most characterized having a baby in training as “somewhat difficult” or “very difficult” at both time periods. Pregnancy complication rates were 33% and 44% for training years 2005 and 2021. As medical education evolves, training programs should be proactive in creating structured support systems for pregnant residents and resident partners to minimize adverse maternal and fetal outcomes and to improve training programs. Future studies are needed to elucidate the causality of higher-than-expected pregnancy complication rates

Synthesis of the fatty esters of solketal and glycerol-formal: biobased specialty chemicals

The caprylic, lauric, palmitic and stearic esters of solketal and glycerol formal were synthesized with high selectivity and in good yields by a solvent-free acid catalyzed procedure. No acetal hydrolysis was observed, notwithstanding the acidic reaction conditions

Urinary Benzene Biomarkers and DNA Methylation in Bulgarian Petrochemical Workers: Study Findings and Comparison of Linear and Beta Regression Models

Chronic occupational exposure to benzene is associated with an increased risk of hematological malignancies such as acute myeloid leukemia (AML), but the underlying mechanisms are still unclear. The main objective of this study was to investigate the association between benzene exposure and DNA methylation, both in repeated elements and candidate genes, in a population of 158 Bulgarian petrochemical workers and 50 unexposed office workers. Exposure assessment included personal monitoring of airborne benzene at work and urinary biomarkers of benzene metabolism (S-phenylmercapturic acid [SPMA] and trans,trans-muconic acid [t,t-MA]) at the end of the work-shift. The median levels of airborne benzene, SPMA and t,t-MA in workers were 0.46 ppm, 15.5 µg/L and 711 µg/L respectively, and exposure levels were significantly lower in the controls. Repeated-element DNA methylation was measured in Alu and LINE-1, and gene-specific methylation in MAGE and p15. DNA methylation levels were not significantly different between exposed workers and controls (P>0.05). Both ordinary least squares (OLS) and beta-regression models were used to estimate benzene-methylation associations. Beta-regression showed better model specification, as reflected in improved coefficient of determination (pseudo $R^2$) and Akaike’s information criterion (AIC). In beta-regression, we found statistically significant reductions in LINE-1 (−0.15%, P<0.01) and p15 (−0.096%, P<0.01) mean methylation levels with each interquartile range (IQR) increase in SPMA. This study showed statistically significant but weak associations of LINE-1 and p15 hypomethylation with SPMA in Bulgarian petrochemical workers. We showed that beta-regression is more appropriate than OLS regression for fitting methylation data

In search of phylogenetic congruence between molecular and morphological data in bryozoans with extreme adult skeletal heteromorphy

peerreview_statement: The publishing and review policy for this title is described in its Aims & Scope. aims_and_scope_url: http://www.tandfonline.com/action/journalInformation?show=aimsScope&journalCode=tsab20© Crown Copyright 2015. This document is the author's final accepted/submitted version of the journal article. You are advised to consult the publisher's version if you wish to cite from it

Baseline characteristics of people experiencing homelessness with a recent drug overdose in the PHOENIx pilot randomised controlled trial

Background: Drug-related deaths in Scotland are the highest in Europe. Half of all deaths in people experiencing homelessness are drug related, yet we know little about the unmet health needs of people experiencing homelessness with recent non-fatal overdose, limiting a tailored practice and policy response to a public health crisis. Methods: People experiencing homelessness with at least one non-fatal street drug overdose in the previous 6 months were recruited from 20 venues in Glasgow, Scotland, and randomised into PHOENIx plus usual care, or usual care. PHOENIx is a collaborative assertive outreach intervention by independent prescriber NHS Pharmacists and third sector homelessness workers, offering repeated integrated, holistic physical, mental and addictions health and social care support including prescribing. We describe comprehensive baseline characteristics of randomised participants. Results: One hundred and twenty-eight participants had a mean age of 42 years (SD 8.4); 71% male, homelessness for a median of 24 years (IQR 12–30). One hundred and eighteen (92%) lived in large, congregate city centre temporary accommodation. A quarter (25%) were not registered with a General Practitioner. Participants had overdosed a mean of 3.2 (SD 3.2) times in the preceding 6 months, using a median of 3 (IQR 2–4) non-prescription drugs concurrently: 112 (87.5%) street valium (benzodiazepine-type new psychoactive substances); 77 (60%) heroin; and 76 (59%) cocaine. Half (50%) were injecting, 50% into their groins. 90% were receiving care from Alcohol and Drug Recovery Services (ADRS), and in addition to using street drugs, 90% received opioid substitution therapy (OST), 10% diazepam for street valium use and one participant received heroin-assisted treatment. Participants had a mean of 2.2 (SD 1.3) mental health problems and 5.4 (SD 2.5) physical health problems; 50% received treatment for physical or mental health problems. Ninety-one per cent had at least one mental health problem; 66% had no specialist mental health support. Participants were frail (70%) or pre-frail (28%), with maximal levels of psychological distress, 44% received one or no daily meal, and 58% had previously attempted suicide. Conclusions: People at high risk of drug-related death continue to overdose repeatedly despite receiving OST. High levels of frailty, multimorbidity, unsuitable accommodation and unmet mental and physical health care needs require a reorientation of services informed by evidence of effectiveness and cost-effectiveness. Trial registration UK Clinical Trials Registry identifier: ISRCTN 10585019