A Future of Failure? The Flow of Technology Talent into Government and Civil Society

This report is an evaluation of the technology talent landscape shows a severe paucity of individuals with technical skills in computer science, data science, and the Internet or other information technology expertise in civil society and government. It investigates broadly the health of the talent pipeline that connects individuals studying or working in information technology-related disciplines to careers in public sector and civil society institutions. Barriers to recruitment and retention of individuals with the requisite skills include compensation, a perceived inability to pursue groundbreaking work, and cultural aversion to innovation

Analytic study of mass segregation around a massive black hole

We analyze the distribution of stars of arbitrary mass function xi(m) around a massive black hole (MBH). Unless xi is strongly dominated by light stars, the steady-state distribution function approaches a power-law in specific energy x=-E/(m*sigma^2)<x_max with index p=m/4M_0, where E is the energy, sigma is the typical velocity dispersion of unbound stars, and M_0 is the mass averaged over m*xi*x_{max}^p. For light-dominated xi, p can grow as large as 3/2 - much steeper than previously thought. A simple prescription for the stellar density profile around MBHs is provided. We illustrate our results by applying them to stars around the MBH in the Milky Way.Comment: Revised version published in Astrophys. J. Let

Global and regional source attribution of Shiga toxin-producing Escherichia coli infections using analysis of outbreak surveillance data

Shiga toxin-producing Escherichia coli (STEC) infections pose a substantial health and economic burden worldwide. To target interventions to prevent foodborne infections, it is important to determine the types of foods leading to illness. Our objective was to determine the food sources of STEC globally and for the six World Health Organization regions. We used data from STEC outbreaks that have occurred globally to estimate source attribution fractions. We categorised foods according to their ingredients and applied a probabilistic model that used information on implicated foods for source attribution. Data were received from 27 countries covering the period between 1998 and 2017 and three regions: the Americas (AMR), Europe (EUR) and Western-Pacific (WPR). Results showed that the top foods varied across regions. The most important sources in AMR were beef (40%; 95% Uncertainty Interval 39-41%) and produce (35%; 95% UI 34-36%). In EUR, the ranking was similar though with less marked differences between sources (beef 31%; 95% UI 28-34% and produce 30%; 95% UI 27-33%). In contrast, the most common source of STEC in WPR was produce (43%; 95% UI 36-46%), followed by dairy (27%; 95% UI 27-27%). Possible explanations for regional variability include differences in food consumption and preparation, frequency of STEC contamination, the potential of regionally predominant STEC strains to cause severe illness and differences in outbreak investigation and reporting. Despite data gaps, these results provide important information to inform the development of strategies for lowering the global burden of STEC infections

Interactions of Satellite Galaxies in Cosmological Dark Matter Halos

We present a statistical analysis of the interactions between satellite galaxies in cosmological dark matter halos taken from fully self-consistent high-resolution simulations of galaxy clusters. We show that the number distribution of satellite encounters has a tail that extends to as many as 3-4 encounters per orbit. On average 30% of the substructure population had at least one encounter (per orbit) with another satellite galaxy. However, this result depends on the age of the dark matter host halo with a clear trend for more interactions in younger systems. We also report a correlation between the number of encounters and the distance of the satellites to the centre of the cluster: satellite galaxies closer to the centre experience more interactions. However, this can be simply explained by the radial distribution of the substructure population and merely reflects the fact that the density of satellites is higher in those regions. In order to find substructure galaxies we applied (and present) a new technique based upon the N-body code MLAPM. This new halo finder MHF (MLAPM's-Halo-Finder) acts with exactly the same accuracy as the N-body code itself and is therefore free of any bias and spurious mismatch between simulation data and halo finding precision related to numerical effects.Comment: 6 pages, 4 figures, accepted by PASA (refereed contribution to the 5th Galactic Chemodynamics workshop, July 2003

A Novel Role for and Potential Therapeutic Targeting of Heme Oxygenase-1 in HIV Neuropathogenesis

HIV-associated neurocognitive disorders (HAND) affect up to 50% of HIV-infected adults despite potent viral suppression with antiretroviral therapy (ART) and are associated with persistent neuronal damage, monocyte/macrophage activation, chronic inflammation, and oxidative stress. Heme oxygenase-1 (HO-1) is a highly inducible, detoxifying enzyme critical for limiting oxidative stress, inflammation, and cellular injury within the central nervous system (CNS) and other tissues. Our analysis of HO-1 expression in the brain prefrontal cortex from HIV-infected individuals demonstrated a significant HO-1 protein deficiency, even in HIV-infected subjects treated with ART. This HO-1 deficiency associated with a diagnosis of HAND and HIV-encephalitis (HIVE) as well as with elevated CNS HIV replication, type I interferon responses, and macrophage activation. Within this cohort longer variants of a HO-1 promoter region (GT)n microsatellite polymorphism, which cause reduced HO-1 gene expression, associated with increased risk of HIVE and elevated CNS macrophage activation. HIV replication in macrophages, a primary CNS HIV reservoir, selectively reduced HO-1 protein and RNA expression and induced production of neurotoxic levels of glutamate. This HO-1 deficiency and associated neurotoxin production was a conserved feature of infection with macrophage-tropic HIV-1 and HIV-2 strains that correlated closely with the extent of replication. ART regimens applied to macrophages after HIV infection was established failed to prevent this HO-1 loss and associated neurotoxin production. HO-1 siRNA knockdown and enzymatic inhibition in HIV-infected macrophages increased supernatant glutamate and neurotoxicity. In contrast, increasing HO-1 expression through siRNA derepression or with pharmacologic inducers, including the CNS-penetrating drug dimethyl fumarate (DMF), decreased supernatant glutamate and neurotoxicity. These findings identify HO-1 as a host factor that is deficient in the brains of HIV-infected individuals and suggest that loss of HO-1 and its protective functions may contribute to HIV neuropathogenesis. Moreover, this work defines a predictable and conserved relationship between HIV replication, HO-1 loss, and neurotoxin production in macrophages that likely reflects processes in place in the HIV-infected brain of individuals receiving ART. Correcting this HO-1 deficiency could provide a novel approach for neuroprotection in individuals with or at risk for developing HAND above that provided by current ART

Mapping Substructures in Dark Matter Halos

We present a detailed study of the real and integrals-of-motion space distributions of a satellite obtained from a self-consistent high-resolution simulation of a galaxy cluster and re-simulated using various analytical halo potentials. We found that the disrupted satellite appears as a coherent structure in integrals-of-motion space in all models (``live'' and analytical potential) although the distribution is significantly smeared for the live host halo. Further the primary mechanism for this smearing is the mass growth of the host, which changes both the energy and angular momentum of the satellite debris. Hence, this must be considered when searching for (stellar) streams with future observational experiments such as RAVE and GAIA.Comment: 5 pages, 6 figures, MNRAS accepted - minor editing without changing the conclusions, a high-resolution version of the paper is available from http://astronomy.swin.edu.au/~sgill/downloads/downloads.htm

Systematic review of SGLT2 receptor inhibitors in dual or triple therapy in type 2 diabetes

Background Despite the number of medications for type 2 diabetes, many people with the condition do not achieve good glycaemic control. Some existing glucose-lowering agents have adverse effects such as weight gain or hypoglycaemia. Type 2 diabetes tends to be a progressive disease, and most patients require treatment with combinations of glucose-lowering agents. The sodium glucose co-transporter 2 (SGLT2) receptor inhibitors are a new class of glucose-lowering agents. Objective To assess the clinical effectiveness and safety of the SGLT2 receptor inhibitors in dual or triple therapy in type 2 diabetes. Data sources MEDLINE, Embase, Cochrane Library (all sections); Science Citation Index; trial registries; conference abstracts; drug regulatory authorities; bibliographies of retrieved papers. Inclusion criteria Randomised controlled trials of SGLT2 receptor inhibitors compared with placebo or active comparator in type 2 diabetes in dual or combination therapy. Methods Systematic review. Quality assessment used the Cochrane risk of bias score. Results Seven trials, published in full, assessed dapagliflozin and one assessed canagliflozin. Trial quality appeared good. Dapagliflozin 10 mg reduced HbA1c by −0.54% (weighted mean differences (WMD), 95% CI −0.67 to −0.40) compared to placebo, but there was no difference compared to glipizide. Canagliflozin reduced HbA1c slightly more than sitagliptin (up to −0.21% vs sitagliptin). Both dapagliflozin and canagliflozin led to weight loss (dapagliflozin WMD −1.81 kg (95% CI −2.04 to −1.57), canagliflozin up to −2.3 kg compared to placebo). Limitations Long-term trial extensions suggested that effects were maintained over time. Data on canagliflozin are currently available from only one paper. Costs of the drugs are not known so cost-effectiveness cannot be assessed. More data on safety are needed, with the Food and Drug Administration having concerns about breast and bladder cancers. Conclusions Dapagliflozin appears effective in reducing HbA1c and weight in type 2 diabetes, although more safety data are needed