261 research outputs found
New perspectives on strong z=0.5 MgII absorbers: are halo-mass and equivalent width anti-correlated?
We measure the mean halo-mass of z=0.5 MgII absorbers using the
cross-correlation (over co-moving scales 0.05-13h^{-1}Mpc) between 1806 MgII
quasar absorption systems and ~250,000 Luminous Red Galaxies (LRGs), both
selected from the SDSS DR3. The MgII systems have rest-frame equivalent widths
W_r(2796)>=0.3A. From the ratio of the MgII-LRG cross-correlation to the
LRG-LRG auto-correlation, we find that the bias ratio between MgII absorbers
and LRGs is 0.65+/-0.08, which implies that the absorber host-galaxies have a
mean halo-mass 20-40 times smaller than that of the LRGs; the MgII absorbers
have halos of mean mass =11.94+/-0.31(stat)+/-0.25(sys). We
demonstrate that this statistical technique, which does not require any
spectroscopic follow-up, does not suffer from contaminants such as stars or
foreground and background galaxies. Finally, we find that the absorber
halo-mass is anti-correlated with the equivalent width. If MgII absorbers were
virialized in galaxy halos a positive M_h-W_r correlation would have been
observed since W_r(2796) is a direct measure of the velocity spread of the MgII
sub-components. Thus, our results demonstrate that the individual clouds of a
MgII system are not virialized in the gaseous halos of the host-galaxies. We
review past results in the literature on the statistics of MgII absorbers and
find that they too require an M_h-W_r anti-correlation. When combined with
measurements of the equivalent width distribution, the M_h-W_r anti-correlation
naturally explains why absorbers with W_r(2796)>=2A are not seen at large
impact parameters. We interpret the M_h-W_r anti-correlation within the
starburst scenario where strong MgII absorbers are produced by
supernovae-driven winds.Comment: 18 pages, 12 EPS figures, Accepted by MNRAS. Full table of MgII
absorbers available at http://www.ast.cam.ac.uk/~mim/pub.html, minor changes
to match the published tex
Contributions of local speech encoding and functional connectivity to audio-visual speech perception
Seeing a speaker’s face enhances speech intelligibility in adverse environments. We investigated the underlying network mechanisms by quantifying local speech representations and directed connectivity in MEG data obtained while human participants listened to speech of varying acoustic SNR and visual context. During high acoustic SNR speech encoding by temporally entrained brain activity was strong in temporal and inferior frontal cortex, while during low SNR strong entrainment emerged in premotor and superior frontal cortex. These changes in local encoding were accompanied by changes in directed connectivity along the ventral stream and the auditory-premotor axis. Importantly, the behavioral benefit arising from seeing the speaker’s face was not predicted by changes in local encoding but rather by enhanced functional connectivity between temporal and inferior frontal cortex. Our results demonstrate a role of auditory-frontal interactions in visual speech representations and suggest that functional connectivity along the ventral pathway facilitates speech comprehension in multisensory environments
Safety of medication use in primary care
© 2014 Royal Pharmaceutical Society.BACKGROUND: Medication errors are one of the leading causes of harmin health care. Review and analysis of errors have often emphasized their preventable nature and potential for reoccurrence. Of the few error studies conducted in primary care to date, most have focused on evaluating individual parts of the medicines management system. Studying individual parts of the system does not provide a complete perspective and may further weaken the evidence and undermine interventions.AIM AND OBJECTIVES: The aim of this review is to estimate the scale of medication errors as a problem across the medicines management system in primary care. Objectives were: To review studies addressing the rates of medication errors, and To identify studies on interventions to prevent medication errors in primary care.METHODS: A systematic search of the literature was performed in PubMed (MEDLINE), International Pharmaceutical Abstracts (IPA), Embase, PsycINFO, PASCAL, Science Direct, Scopus, Web of Knowledge, and CINAHL PLUS from 1999 to November, 2012. Bibliographies of relevant publications were searched for additional studies.KEY FINDINGS: Thirty-three studies estimating the incidence of medication errors and thirty-six studies evaluating the impact of error-prevention interventions in primary care were reviewed. This review demonstrated that medication errors are common, with error rates between 90%, depending on the part of the system studied, and the definitions and methods used. The prescribing stage is the most susceptible, and that the elderly (over 65 years), and children (under 18 years) are more likely to experience significant errors. Individual interventions demonstrated marginal improvements in medication safety when implemented on their own.CONCLUSION: Targeting the more susceptible population groups and the most dangerous aspects of the system may be a more effective approach to error management and prevention. Co-implementation of existing interventions at points within the system may offer time- and cost-effective options to improving medication safety in primary care.Peer reviewe
Detection and attention for auditory, visual, and audiovisual speech in children with hearing loss
Mutant huntingtin causes defective actin remodeling during stress: defining a new role for transglutaminase 2 in neurodegenerative disease
Huntington's disease (HD) is caused by an expanded CAG tract in the Interesting transcript 15 (IT15) gene encoding the 350 kDa huntingtin protein. Cellular stresses can trigger the release of huntingtin from the endoplasmic reticulum, allowing huntingtin nuclear entry. Here, we show that endogenous, full-length huntingtin localizes to nuclear cofilin–actin rods during stress and is required for the proper stress response involving actin remodeling. Mutant huntingtin induces a dominant, persistent nuclear rod phenotype similar to that described in Alzheimer's disease for cytoplasmic cofilin–actin rods. Using live cell temporal studies, we show that this stress response is similarly impaired when mutant huntingtin is present, or when normal huntingtin levels are reduced. In clinical lymphocyte samples from HD patients, we have quantitatively detected cross-linked complexes of actin and cofilin with complex formation varying in correlation with disease progression. By live cell fluorescence lifetime imaging measurement–Förster resonant energy transfer studies and western blot assays, we quantitatively observed that stress-activated tissue transglutaminase 2 (TG2) is responsible for the actin–cofilin covalent cross-linking observed in HD. These data support a direct role for huntingtin in nuclear actin re-organization, and describe a new pathogenic mechanism for aberrant TG2 enzymatic hyperactivity in neurodegenerative diseases
Genetic association study of QT interval highlights role for calcium signaling pathways in myocardial repolarization.
The QT interval, an electrocardiographic measure reflecting myocardial repolarization, is a heritable trait. QT prolongation is a risk factor for ventricular arrhythmias and sudden cardiac death (SCD) and could indicate the presence of the potentially lethal mendelian long-QT syndrome (LQTS). Using a genome-wide association and replication study in up to 100,000 individuals, we identified 35 common variant loci associated with QT interval that collectively explain ∼8-10% of QT-interval variation and highlight the importance of calcium regulation in myocardial repolarization. Rare variant analysis of 6 new QT interval-associated loci in 298 unrelated probands with LQTS identified coding variants not found in controls but of uncertain causality and therefore requiring validation. Several newly identified loci encode proteins that physically interact with other recognized repolarization proteins. Our integration of common variant association, expression and orthogonal protein-protein interaction screens provides new insights into cardiac electrophysiology and identifies new candidate genes for ventricular arrhythmias, LQTS and SCD
The twilight of the Liberal Social Contract? On the Reception of Rawlsian Political Liberalism
This chapter discusses the Rawlsian project of public reason, or public justification-based 'political' liberalism, and its reception. After a brief philosophical rather than philological reconstruction of the project, the chapter revolves around a distinction between idealist and realist responses to it. Focusing on political liberalism’s critical reception illuminates an overarching question: was Rawls’s revival of a contractualist approach to liberal legitimacy a fruitful move for liberalism and/or the social contract tradition? The last section contains a largely negative answer to that question. Nonetheless the chapter's conclusion shows that the research programme of political liberalism provided and continues to provide illuminating insights into the limitations of liberal contractualism, especially under conditions of persistent and radical diversity. The programme is, however, less receptive to challenges to do with the relative decline of the power of modern states
Allergen immunotherapy with nanoparticles containing lipopolysaccharide from Brucella ovis
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