Open Problems on Central Simple Algebras

We provide a survey of past research and a list of open problems regarding central simple algebras and the Brauer group over a field, intended both for experts and for beginners.Comment: v2 has some small revisions to the text. Some items are re-numbered, compared to v

High, usual and impaired functioning in community-dwelling older men and women: Findings from the MacArthur Foundation Research Network on successful aging

The objective of this study is to determine the range of complex physical and cognitive abilities of older men and women functioning at high, medium and impaired ranges and to determine the psychosocial and physiological conditions that discriminate those in the high functioning group from those functioning at middle or impaired ranges. The subjects for this study were drawn from men and women aged 70-79 from 3 Established Populations for the Epidemiologic Study of the Elderly (EPESE) programs in East Boston MA, New Haven CT, and Durham County NC screened on the basis of criteria of physical and cognitive function. In 1988, 4030 men and women were screened as part of their annual EPESE interview. 1192 men and women met criteria for "high functioning". Age and sex-matched subjects were selected to represent the medium (n = 80) and low (n = 82) functioning groups. Physical and cognitive functioning was assessed from performance-based examinations and self-reported abilities. Physical function measures focused on balance, gait, and upper body strength. Cognitive exams assessed memory, language, abstraction, and praxis. Significant differences for every performance-based examination of physical and cognitive function were observed across functioning groups. Low functioning subjects were almost 3 times as likely to have an income of [les]$5000 compared to the high functioning group. They were less likely to have completed high school. High functioning subjects smoked cigarettes less and exercised more than others. They had higher levels of DHEA-S and peak expiratory flow rate. High functioning elders were more likely to engage in volunteer activities and score higher on scales of self-efficacy, mastery and report fewer psychiatric symptoms.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/31100/1/0000778.pd

XMM-Newton Reflection Grating Spectrometer Observations of Discrete Soft-X-ray Emission Features from NGC 1068

We present the first high-resolution, soft-X-ray spectrum of the prototypical Seyfert 2 galaxy, NGC 1068. This spectrum was obtained with the XMM-Newton Reflection Grating Spectrometer. Emission lines from H-like and He-like low-Z ions (from C to Si) and Fe-L-shell ions dominate the spectrum. Strong, narrow radiative recombination continua (RRC) for several ions are also present, implying that most of the observed soft-X-ray emission arises in low-temperature (few eV) plasma. This plasma is photoionized by the inferred nuclear continuum (obscured along our line of sight), as in the unified model of active galactic nuclei (AGN). We find excess emission (compared with pure recombination) in all resonance lines (np to 1s) up to the photoelectric edge, demonstrating the importance of photoexcitation as well. We introduce a simple model of a cone of plasma irradiated by the nuclear continuum; the line emission we observe along our line of sight perpendicular to the cone is produced through recombination/radiative cascade following photoionization and radiative decay following photoexcitation. A remarkably good fit is obtained to the H-like/He-like ionic line series, with inferred radial ionic column densities consistent with recent observations of warm absorbers in Seyfert 1 galaxies. Previous Chandra imaging revealed a large (extending out to 500 pc) ionization cone containing most of the X-ray flux, implying that the warm absorber in NGC 1068 is a large-scale outflow. To explain the ionic column densities, a broad, flat distribution in the logarithm of the ionization parameter ($\xi=L_X/n_e r^2$) is necessary, spanning $\log\xi=0$--3. This suggests either radially-stratified ionization zones or the existence of a broad density distribution (spanning a few orders of magnitude) at each radius.Comment: 23 pages, 16 figures, ApJ (accepted). XSPEC local model "photo" is available at http://xmm.astro.columbia.edu/research.htm

Search for new phenomena in final states with an energetic jet and large missing transverse momentum in pp collisions at √ s = 8 TeV with the ATLAS detector

Results of a search for new phenomena in final states with an energetic jet and large missing transverse momentum are reported. The search uses 20.3 fb−1 of √ s = 8 TeV data collected in 2012 with the ATLAS detector at the LHC. Events are required to have at least one jet with pT > 120 GeV and no leptons. Nine signal regions are considered with increasing missing transverse momentum requirements between Emiss T > 150 GeV and Emiss T > 700 GeV. Good agreement is observed between the number of events in data and Standard Model expectations. The results are translated into exclusion limits on models with either large extra spatial dimensions, pair production of weakly interacting dark matter candidates, or production of very light gravitinos in a gauge-mediated supersymmetric model. In addition, limits on the production of an invisibly decaying Higgs-like boson leading to similar topologies in the final state are presente

Development of the PSYCHS: Positive SYmptoms and Diagnostic Criteria for the CAARMS Harmonized with the SIPS

Aim: To harmonize two ascertainment and severity rating instruments commonly used for the clinical high risk syndrome for psychosis (CHR-P): the Structured Interview for Psychosis-risk Syndromes (SIPS) and the Comprehensive Assessment of At-Risk Mental States (CAARMS). Methods: The initial workshop is described in the companion report from Addington et al. After the workshop, lead experts for each instrument continued harmonizing attenuated positive symptoms and criteria for psychosis and CHR-P through an intensive series of joint videoconferences. Results: Full harmonization was achieved for attenuated positive symptom ratings and psychosis criteria, and modest harmonization for CHR-P criteria. The semi-structured interview, named Positive SYmptoms and Diagnostic Criteria for the CAARMS Harmonized with the SIPS (PSYCHS), generates CHR-P criteria and severity scores for both CAARMS and SIPS. Conclusions: Using the PSYCHS for CHR-P ascertainment, conversion determination, and attenuated positive symptom severity rating will help in comparing findings across studies and in meta-analyses

Variation in the Glucose Transporter gene <i>SLC2A2 </i>is associated with glycaemic response to metformin

Metformin is the first-line antidiabetic drug with over 100 million users worldwide, yet its mechanism of action remains unclear1. Here the Metformin Genetics (MetGen) Consortium reports a three-stage genome-wide association study (GWAS), consisting of 13,123 participants of different ancestries. The C allele of rs8192675 in the intron of SLC2A2, which encodes the facilitated glucose transporter GLUT2, was associated with a 0.17% (P = 6.6 × 10−14) greater metformin-induced reduction in hemoglobin A1c (HbA1c) in 10,577 participants of European ancestry. rs8192675 was the top cis expression quantitative trait locus (cis-eQTL) for SLC2A2 in 1,226 human liver samples, suggesting a key role for hepatic GLUT2 in regulation of metformin action. Among obese individuals, C-allele homozygotes at rs8192675 had a 0.33% (3.6 mmol/mol) greater absolute HbA1c reduction than T-allele homozygotes. This was about half the effect seen with the addition of a DPP-4 inhibitor, and equated to a dose difference of 550 mg of metformin, suggesting rs8192675 as a potential biomarker for stratified medicine

Postdigital Dialogue

This article is a multi-authored experimental postdigital dialogue about postdigital dialogue. Fourteen authors were invited to produce their sections, followed by two author-reviewers who examined the article as a whole. Authors were invited to reflect on Petar Jandric’s book Learning in the age of digital reason (2017) or to produce completely new insights. The article also contains a summary of book symposium on Learning in the age of digital reason held at the 2017 American Educational Research Conference (AERA). The authors are tentatively confident that this article produces more knowledge than the arithmetic sum of its constituent parts. However, they are also very aware of its limits and insist that their conclusions are not consensual or homogenous. As traditional forms of research increasingly fail to describe our current reality, they present this article as an experiment and a possible starting point for developing new dialogical research approaches fit for our postdigital reality

Systems genetics identifies a convergent gene network for cognition and neurodevelopmental disease

Genetic determinants of cognition are poorly characterized, and their relationship to genes that confer risk for neurodevelopmental disease is unclear. Here we performed a systems-level analysis of genome-wide gene expression data to infer gene-regulatory networks conserved across species and brain regions. Two of these networks, M1 and M3, showed replicable enrichment for common genetic variants underlying healthy human cognitive abilities, including memory. Using exome sequence data from 6,871 trios, we found that M3 genes were also enriched for mutations ascertained from patients with neurodevelopmental disease generally, and intellectual disability and epileptic encephalopathy in particular. M3 consists of 150 genes whose expression is tightly developmentally regulated, but which are collectively poorly annotated for known functional pathways. These results illustrate how systems-level analyses can reveal previously unappreciated relationships between neurodevelopmental disease–associated genes in the developed human brain, and provide empirical support for a convergent gene-regulatory network influencing cognition and neurodevelopmental disease

Search for a new resonance decaying to a W or Z boson and a Higgs boson in the ll/lv/vv + bb final states with the ATLAS detector

A search for a new resonance decaying to a W or Z boson and a Higgs boson in the ll/lv/vv + bb final states is performed using 20.3 fb −1 of pp collision data recorded at √ s = 8 TeV with the ATLAS detector at the Large Hadron Collider. The search is conducted by examining the W H / Z H invariant mass distribution for a localized excess. No significant deviation from the Standard Model background prediction is observed. The results are interpreted in terms of constraints on the Minimal Walking Technicolor model and on a simplified approach based on a phenomenological Lagrangian of Heavy Vector Triplets

Search for high-mass diboson resonances with boson-tagged jets in proton-proton collisions at √s=8 TeV with the ATLAS detector

A search is performed for narrow resonances decaying into WW, WZ, or ZZ boson pairs using 20.3 fb−1 of proton-proton collision data at a centre-of-mass energy of √s=8 TeV recorded with the ATLAS detector at the Large Hadron Collider. Diboson resonances with masses in the range from 1.3 to 3.0 TeV are sought after using the invariant mass distribution of dijets where both jets are tagged as a boson jet, compatible with a highly boosted W or Z boson decaying to quarks, using jet mass and substructure properties. The largest deviation from a smoothly falling background in the observed dijet invariant mass distribution occurs around 2 TeV in the WZ channel, with a global significance of 2.5 standard deviations. Exclusion limits at the 95% confidence level are set on the production cross section times branching ratio for the WZ final state of a new heavy gauge boson, W′, and for the WW and ZZ final states of Kaluza-Klein excitations of the graviton in a bulk Randall-Sundrum model, as a function of the resonance mass. W′ bosons with couplings predicted by the extended gauge model in the mass range from 1.3 to 1.5 TeV are excluded at 95% confidence level