457 research outputs found
Gemini NIFS survey of feeding and feedback processes in nearby Active Galaxies: I - Stellar kinematics
We use the Gemini Near-Infrared Integral Field Spectrograph (NIFS) to map the
stellar kinematics of the inner few hundred parsecs of a sample of 16 nearby
Seyfert galaxies, at a spatial resolution of tens of parsecs and spectral
resolution of 40 km/s. We find that the line-of-sight (LOS) velocity fields for
most galaxies are well reproduced by rotating disk models. The kinematic
position angle (PA) derived for the LOS velocity field is consistent with the
large scale photometric PA. The residual velocities are correlated with the
hard X-ray luminosity, suggesting that more luminous AGN have a larger impact
in the surrounding stellar dynamics. The central velocity dispersion values are
usually higher than the rotation velocity amplitude, what we attribute to the
strong contribution of bulge kinematics in these inner regions. For 50% of the
galaxies, we find an inverse correlation between the velocities and the
Gauss-Hermitte moment, implying red wings in the blueshifted side and blue
wings in the redshifted side of the velocity field, attributed to the movement
of the bulge stars lagging the rotation. Two of the 16 galaxies (NGC 5899 and
Mrk 1066) show an S-shape zero velocity line, attributed to the gravitational
potential of a nuclear bar. Velocity dispersion maps show rings of low-
values (50-80 km/s) for 4 objects and "patches" of low-sigma for 6 galaxies at
150-250 pc from the nucleus, attributed to young/ intermediate age stellar
populations.Comment: To be published in MNRA
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Bilateral Lung Transplantation in a Patient with Humoral Immune Deficiency: A Case Report with Review of the Literature
Humoral immune deficiencies have been associated with noninfectious disease complications including autoimmune cytopenias and pulmonary disease. Herein we present a patient who underwent splenectomy for autoimmune cytopenias and subsequently was diagnosed with humoral immune deficiency in the context of recurrent infections. Immunoglobulin analysis prior to initiation of intravenous immunoglobulin (IVIG) therapy was notable for low age-matched serum levels of IgA (11 mg/dL), IgG2 (14 mg/L), and IgG4 (5 mg/L) with a preserved total level of IgG. Flow cytometry was remarkable for B cell maturation arrest at the IgM+/IgD+ stage. Selective screening for known primary immune deficiency-causing genetic defects was negative. The disease course was uniquely complicated by the development of pulmonary arteriovenous malformations (AVMs), ultimately requiring bilateral lung transplantation in 2012. This is a patient with humoral immune deficiency that became apparent only after splenectomy, which argues for routine immunologic evaluation prior to vaccination and splenectomy. Lung transplantation is a rare therapeutic endpoint and to our knowledge has never before been described in a patient with humoral immune deficiency for the indication of pulmonary AVMs
Biogenic Nitrogen Gas Production at the Oxic–Anoxic Interface in the Cariaco Basin, Venezuela
Excess nitrogen gas (N2xs) was measured in samples collected at six locations in the eastern and western sub-basins of the Cariaco Basin, Venezuela, in September 2008 (non-upwelling conditions) and March 2009 (upwelling conditions). During both sampling periods, N2xs concentrations were below detection in surface waters, increasing to ~ 22 μmol N kg−1 at the oxic–anoxic interface ([O2] \u3c ~ 4 μmol kg−1, ~ 250 m). Below the oxic–anoxic interface (300–400 m), the average concentration of N2xs was 24.7 ± 1.9 μmol N kg−1 in September 2008 and 27.5 ± 2.0 μmol N kg−1 in March 2009, i.e., N2xs concentrations within this depth interval were ~ 3 μmol N kg−1 higher (p \u3c 0.001) during the upwelling season compared to the non-upwelling period. These results suggest that N-loss in the Cariaco Basin may vary seasonally in response to changes in the flux of sinking particulate organic matter. We attribute the increase in N2xs concentrations, or N-loss, observed during upwelling to: (1) higher availability of fixed nitrogen derived from suspended and sinking particles at the oxic–anoxic interface and/or (2) enhanced ventilation at the oxic–anoxic interface during upwelling
Gemini NIFS survey of feeding and feedback in nearbyActive Galaxies - III. Ionized versus warm molecular gasmasses and distributions
We have used the Gemini Near-Infrared Integral Field Spectrograph (NIFS) in
the J and K bands to map the distribution, excitation and kinematics of the
ionized HII and warm molecular gas H, in the inner few 100 pc of 6 nearby
active galaxies: NGC 788, Mrk 607, NGC 3227, NGC 3516, NGC 5506, NGC 5899. {For
most galaxies, this is the first time that such maps have been obtained}. The
ionized and H gas show distinct kinematics: while the H gas is mostly
rotating in the galaxy plane with low velocity dispersion (), the
ionized gas usually shows signatures of outflows associated with higher
values, most clearly seen in the [FeII] emission line. These two gas
species also present distinct flux distributions: the H is more uniformly
spread over the whole galaxy plane, while the ionized gas is more concentrated
around the nucleus and/or collimated along the ionization axis of its Active
Galactic Nucleus (AGN), presenting a steeper gradient in the average surface
mass density profile than the H gas. The total HII masses cover the range
M, with surface mass densities in the range
3-150 M pc, while for the warm H the values are 10
times lower. We estimate that the available gas reservoir is at least
100 times more massive than needed to power the AGN. If this gas form new stars
the star-formation rates, obtained from the Kennicutt-schmidt scalling
relation, are in the range 1-260 10 M yr. But
the gas will also - at least in part - be ejected in the form of the observed
otflows
Carotid Plaque Neovascularization and Hemorrhage Detected by MR Imaging are Associated with Recent Cerebrovascular Ischemic Events
BACKGROUND AND PURPOSE: Pathologic studies suggest that neovascularization and hemorrhage are important features of plaque vulnerability for disruption. Our aim was to determine the associations of these features in carotid plaques with previous cerebrovascular ischemic events by using highresolution CE-MRI
Biomarkers and degree of atherosclerosis are independently associated with incident atherosclerotic cardiovascular disease in a primary prevention cohort: The ARIC study
Biomarkers and atherosclerosis imaging have been studied individually for association with incident cardiovascular disease (CVD); however, limited data exist on whether the biomarkers are associated with events with a similar magnitude in the presence of atherosclerosis. In this study, we assessed whether the presence of atherosclerosis as measured by carotid intima media thickness (cIMT) affects the association between biomarkers known to be associated with coronary heart disease (CHD) and incident cardiovascular disease (CVD) in a primary prevention cohort
Relative risks of chronic kidney disease for mortality and end-stage renal disease across races are similar
Some suggest race-specific cutpoints for kidney measures to define and stage chronic kidney disease (CKD), but evidence for race-specific clinical impact is limited. To address this issue, we compared hazard ratios of estimated glomerular filtration rates (eGFR) and albuminuria across races using meta-regression in 1.1 million adults (75% Asians, 21% Whites, and 4% Blacks) from 45 cohorts. Results came mainly from 25 general population cohorts comprising 0.9 million individuals. The associations of lower eGFR and higher albuminuria with mortality and end-stage renal disease (ESRD) were largely similar across races. For example, in Asians, Whites, and Blacks, the adjusted hazard ratios (95% confidence interval) for eGFR 45-59 versus 90-104 ml/min per 1.73 m(2) were 1.3 (1.2-1.3), 1.1 (1.0-1.2), and 1.3 (1.1-1.7) for all-cause mortality, 1.6 (1.5-1.7), 1.4 (1.2-1.7), and 1.4 (0.7-2.9) for cardiovascular mortality, and 27.6 (11.1-68.7), 11.2 (6.0-20.9), and 4.1 (2.2-7.5) for ESRD, respectively. The corresponding hazard ratios for urine albumin-to-creatinine ratio 30-299 mg/g or dipstick 1+ versus an albumin-to-creatinine ratio under 10 or dipstick negative were 1.6 (1.4-1.8), 1.7 (1.5-1.9), and 1.8 (1.7-2.1) for all-cause mortality, 1.7 (1.4-2.0), 1.8 (1.5-2.1), and 2.8 (2.2-3.6) for cardiovascular mortality, and 7.4 (2.0-27.6), 4.0 (2.8-5.9), and 5.6 (3.4-9.2) for ESRD, respectively. Thus, the relative mortality or ESRD risks of lower eGFR and higher albuminuria were largely similar among three major races, supporting similar clinical approach to CKD definition and staging, across races
MicroRNA-221 Modulates RSV Replication in Human Bronchial Epithelium by Targeting NGF Expression
Background: Early-life infection by respiratory syncytial virus (RSV) is associated with aberrant expression of the prototypical neurotrophin nerve growth factor (NGF) and its cognate receptors in human bronchial epithelium. However, the chain of events leading to this outcome, and its functional implications for the progression of the viral infection, has not been elucidated. This study sought to test the hypothesis that RSV infection modulates neurotrophic pathways in human airways by silencing the expression of specific microRNAs (miRNAs), and that this effect favors viral growth by interfering with programmed death of infected cells. Methodology: Human bronchial epithelial cells infected with green fluorescent protein-expressing RSV (rgRSV) were screened with multiplex qPCR arrays, and miRNAs significantly affected by the virus were analyzed for homology with mRNAs encoding neurotrophic factors or receptors. Mimic sequences of selected miRNAs were transfected into noninfected bronchial cells to confirm the role of each of them in regulating neurotrophins expression at the gene and protein level, and to study their influence on cell cycle and viral replication. Principal Findings: RSV caused downregulation of 24 miRNAs and upregulation of 2 (p,0.01). Homology analysis of microarray data revealed that 6 of those miRNAs exhibited a high degree of complementarity to NGF and/or one of its cognate receptors TrKA and p75 NTR. Among the selected miRNAs, miR-221 was significantly downregulated by RSV and it
Migration as a form of workforce attrition: a nine-country study of pharmacists
Background
There is a lack of evidence to inform policy development on the reasons why health professionals migrate. Few studies have sought to empirically determine factors influencing the intention to migrate and none have explored the relationship between factors. This paper reports on the first international attempt to investigate the migration intentions of pharmacy students and identify migration factors and their relationships.
Methods
Responses were gathered from 791 final-year pharmacy students from nine countries: Australia, Bangladesh, Croatia, Egypt, Portugal, Nepal, Singapore, Slovenia and Zimbabwe. Data were analysed by means of Principal Components Analysis (PCA) and two-step cluster analysis to determine the relationships between factors influencing migration and the characteristics of subpopulations most likely and least likely to migrate.
Results
Results showed a significant difference in attitudes towards the professional and sociopolitical environment of the home country and perceptions of opportunities abroad between those who have no intention of migrating and those who intend to migrate on a long-term basis. Attitudes of students planning short-term migration were not significantly different from those of students who did not intend to migrate. These attitudes, together with gender, knowledge of other migrant pharmacists and past experiences abroad, are associated with an increased propensity for migration.
Conclusion
Given the influence of the country context and environment on migration intentions, research and policy should frame the issue of migration in the context of the wider human resource agenda, thus viewing migration as one form of attrition and a symptom of other root causes. Remuneration is not an independent stand-alone factor influencing migration intentions and cannot be decoupled from professional development factors. Comprehensive human resource policy development that takes into account the issues of both remuneration and professional development are necessary to encourage retention
Action selection and action awareness
Human actions are often classified as either internally generated, or externally specified in response to environmental cues. These two modes of action selection have distinct neural bases, but few studies investigated how the mode of action selection affects the subjective experience of action. We measured the experience of action using the subjective compression of the interval between actions and their effects, known as ‘temporal binding’. Participants performed either a left or a right key press, either in response to a specific cue, or as they freely chose. Moreover, the time of each keypress could either be explicitly cued to occur in one of two designated time intervals, or participants freely chose in which interval to act. Each action was followed by a specific tone. Participants judged the time of their actions or the time of the tone. Temporal binding was found for both internally generated and for stimulus-based actions. However, the amount of binding depended on whether or not both the choice and the timing of action were selected in the same way. Stronger binding was observed when both action choice and action timing were internally generated or externally specified, compared to conditions where the two parameters were selected by different routes. Our result suggests that temporal action–effect binding depends on how actions are selected. Binding is strongest when actions result from a single mode of selection
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