315 research outputs found

    Spatial distribution of unidentified infrared bands and extended red emission in the compact galactic HII region Sh 152

    Get PDF
    We present visible and near IR images of the compact HII region Sh 152. Some of these images reveal the presence of Extended Red Emission (ERE) around 698 nm and emission from Unidentified Infra Red Bands (UIRBs) at 3.3 and 6.2 micron. Other images show the near infrared (7-12 micron) continuous emission of the nebula. The ERE emission is found to coincide with the ionized region and significantly differ from the UIRBs location. Also some evidence is found in favor of grains as carriers for ERE.Comment: 3 pages, 4 figures, to be published in the proceedings of the colloquium "The universe as seen by ISO" help in Paris, October 20-23, 1998 ; available in html format at http://www.obs-hp.fr/preprints.htm

    A Turn-over in the Galaxy Luminosity Function of the Coma Cluster Core?

    Get PDF
    Our previous study of the faint end (R\leq21.5) of the galaxy luminosity function (GLF) was based on spectroscopic data in a small region near the Coma cluster center. In this previous study Adami et al. (1998) suggested, with moderate statistical significance, that the number of galaxies actually belonging to the cluster was much smaller than expected. This led us to increase our spectroscopic sample. Here, we have improved the statistical significance of the results of the Coma GLF faint end study (R\leq22.5) by using a sample of 85 redshifts. This includes both new spectroscopic data and a literature compilation. The relatively small number of faint galaxies belonging to Coma that was suggested by Adami et al. (1998) and Secker et al. (1998) has been confirmed with these new observations. We also confirm that the color-magnitude relation is not well suited for finding the galaxies inside the Coma cluster core, close to the center at magnitudes fainter than R\sim19. We show that there is an enhancement in the Coma line of sight of field galaxies compared to classical field counts. This can be explained by the contribution of groups and of a distant z0.5z\sim 0.5 cluster along the line of sight. The result is that the Coma GLF appears to turn-over or at least to become flat for the faint galaxies. We suggest that this is due to environmental effects.Comment: 8 pages, 6 postscript figures, accepted in A&A, new table 1, updated figure

    A Comprehensive Study to Delineate the Role of an Extracellular Vesicle-Associated MicroRNA-29a in Chronic Methamphetamine Use Disorder

    Get PDF
    Extracellular vesicles (EVs), which express a repertoire of cargo molecules (cf. proteins, microRNA, lipids, etc.), have been garnering a prominent role in the modulation of several cellular processes. Here, using both non-human primate and rodent model systems, we provide evidence that brain-derived EV (BDE) miRNA, miR-29a-3p (mir-29a), is significantly increased during chronic methamphetamine (MA) exposure. Further, miR-29a levels show significant increase both with drug-seeking and reinstatement in a rat MA self-administration model. We also show that EV-associated miR-29a is enriched in EV pool comprising of small EVs and exomeres and further plays a critical role in MA-induced inflammation and synaptodendritic damage. Furthermore, treatment with the anti-inflammatory drug ibudilast (AV411), which is known to reduce MA relapse, decreased the expression of miR-29a and subsequently attenuated inflammation and rescued synaptodendritic injury. Finally, using plasma from MUD subjects, we provide translational evidence that EV-miR29a could potentially serve as a biomarker to detect neuronal damage in humans diagnosed with MA use disorder (MUD). In summary, our work suggests that EV-associated miR-29a-3p plays a crucial role in MUD and might be used as a potential blood-based biomarker for detecting chronic inflammation and synaptic damage

    A comprehensive study to delineate the role of an extracellular vesicle-associated microRNA-29a in chronic methamphetamine use disorder

    Get PDF
    Extracellular vesicles (EVs), which express a repertoire of cargo molecules (cf. proteins, microRNA, lipids, etc.), have been garnering a prominent role in the modulation of several cellular processes. Here, using both non-human primate and rodent model systems, we provide evidence that brain-derived EV (BDE) miRNA, miR- 29a-3p (mir-29a), is significantly increased during chronic methamphetamine (MA) exposure. Further, miR-29a levels show significant increase both with drug-seeking and reinstatement in a rat MA self-administration model. We also show that EVassociated miR-29a is enriched in EV pool comprising of small EVs and exomeres and further plays a critical role in MA-induced inflammation and synaptodendritic damage. Furthermore, treatment with the anti-inflammatory drug ibudilast (AV411), which is known to reduce MA relapse, decreased the expression of miR-29a and subsequently attenuated inflammation and rescued synaptodendritic injury. Finally, using plasma fromMUDsubjects, we provide translational evidence that EV-miR29a could potentially serve as a biomarker to detect neuronal damage in humans diagnosed with MA use disorder (MUD). In summary, our work suggests that EVassociated miR-29a-3p plays a crucial role in MUD and might be used as a potential blood-based biomarker for detecting chronic inflammation and synaptic damage

    Relative luminosity measurement of the LHC with the ATLAS forward calorimeter

    Full text link
    In this paper it is shown that a measurement of the relative luminosity changes at the LHC may be obtained by analysing the currents drawn from the high voltage power supplies of the electromagnetic section of the forward calorimeter of the ATLAS detector. The method was verified with a reproduction of a small section of the ATLAS forward calorimeter using proton beams of known beam energies and variable intensities at the U-70 accelerator at IHEP in Protvino, Russia. The experimental setup and the data taking during a test beam run in April 2008 are described in detail. A comparison of the measured high voltage currents with reference measurements from beam intensity monitors shows a linear dependence on the beam intensity. The non-linearities are measured to be less than 0.5 % combining statistical and systematic uncertainties.Comment: 16 page

    Hypertensive response to exercise in adult patients with repaired aortic coarctation

    Get PDF
    OBJECTIVE: The clinical and prognostic implications of a hypertensive response to exercise after repair of coarctation of the aorta (CoA) remain controversial. We aimed to determine the prevalence of a hypertensive response to exercise, identify factors associated with peak exercise systolic blood pressure (SBP) and explore the association of peak exercise SBP with resting blood pressure and cardiovascular events during follow-up. METHODS: From the Dutch national CONgenital CORvitia (CONCOR) registry, adults with repaired CoA who underwent exercise stress testing were included. A hypertensive response to exercise was defined as a peak exercise SBP ≥210 mm Hg in men and ≥190 mm Hg in women. Cardiovascular events consisted of coronary artery disease, stroke, aortic complications and cardiovascular death. RESULTS: Of the original cohort of 920 adults with repaired CoA, 675 patients (median age 24 years (range 16-72 years)) underwent exercise stress testing. Of these, 299 patients (44%) had a hypertensive response to exercise. Mean follow-up duration was 10.1 years. Male sex, absence of a bicuspid aortic valve and elevated resting SBP were independently associated with increased peak exercise SBP. Peak exercise SBP was positively predictive of office SBP (β=0.11, p<0.001) and 24-hour SBP (β=0.05, p=0.03) at follow-up, despite correction for baseline SBP. During follow-up, 100 patients (15%) developed at least 1 cardiovascular event. Peak exercise SBP was not significantly associated with the occurrence of cardiovascular events (HR 0.994 (95% CI 0.987 to 1.001), p=0.11). CONCLUSIONS: A hypertensive response to exercise was present in nearly half of the patients in this large, prospective cohort of adults with repaired CoA. Risk factors for increased peak exercise SBP were male sex, absence of a bicuspid aortic valve and elevated resting SBP. Increased peak exercise SBP independently predicted hypertension at follow-up. These results support close follow-up of patients with a hypertensive response to exercise to ensure timely diagnosis and treatment of future hypertension

    Cardiovascular morbidity and mortality in adult patients with repaired aortic coarctation

    Get PDF
    BACKGROUND: The long‐term burden of cardiovascular disease after repair of coarctation of the aorta (CoA) has not been elucidated. We aimed to determine the incidence of and risk factors for cardiovascular events in adult patients with repaired CoA. Additionally, mortality rates were compared between adults with repaired CoA and the general population. METHODS AND RESULTS: Using the Dutch Congenital Corvitia (CONCOR) registry, patients aged ≥16 years with previous surgical or transcatheter CoA repair from 5 tertiary referral centers were included. Cardiovascular events were recorded, comprising coronary artery disease, stroke/transient ischemic attack, aortic complications, arrhythmias, heart failure hospitalizations, endocarditis, and cardiovascular death. In total, 920 patients (median age, 24 years [range 16–74 years]) were included. After a mean follow‐up of 9.3±5.1 years, 191 patients (21%) experienced at least 1 cardiovascular event. A total of 270 cardiovascular events occurred, of which aortic complications and arrhythmias were most frequent. Older age at initial CoA repair (hazard ratio [HR], 1.017; 95% CI, 1.000–1.033 [P=0.048]) and elevated left ventricular mass index (HR, 1.009; 95% CI, 1.005–1.013 [P<0.001]) were independently associated with an increased risk of cardiovascular events. The mortality rate was 3.3 times higher than expected based on an age‐ and sex‐matched cohort from the Dutch general population (standardized mortality ratio, 3.3; 95% CI, 2.3–4.4 [P<0.001]). CONCLUSIONS: This large, prospective cohort of adults with repaired CoA showed a high burden of cardiovascular events, particularly aortic complications and arrhythmias, during long‐term follow‐up. Older age at initial CoA repair and elevated left ventricular mass index were independent risk factors for the occurrence of cardiovascular events. Mortality was 3.3‐fold higher compared with the general population. These results advocate stringent follow‐up after CoA repair and emphasize the need for improved preventive strategies

    Standalone vertex finding in the ATLAS muon spectrometer

    Get PDF
    A dedicated reconstruction algorithm to find decay vertices in the ATLAS muon spectrometer is presented. The algorithm searches the region just upstream of or inside the muon spectrometer volume for multi-particle vertices that originate from the decay of particles with long decay paths. The performance of the algorithm is evaluated using both a sample of simulated Higgs boson events, in which the Higgs boson decays to long-lived neutral particles that in turn decay to bbar b final states, and pp collision data at √s = 7 TeV collected with the ATLAS detector at the LHC during 2011

    Measurements of Higgs boson production and couplings in diboson final states with the ATLAS detector at the LHC

    Get PDF
    Measurements are presented of production properties and couplings of the recently discovered Higgs boson using the decays into boson pairs, H →γ γ, H → Z Z∗ →4l and H →W W∗ →lνlν. The results are based on the complete pp collision data sample recorded by the ATLAS experiment at the CERN Large Hadron Collider at centre-of-mass energies of √s = 7 TeV and √s = 8 TeV, corresponding to an integrated luminosity of about 25 fb−1. Evidence for Higgs boson production through vector-boson fusion is reported. Results of combined fits probing Higgs boson couplings to fermions and bosons, as well as anomalous contributions to loop-induced production and decay modes, are presented. All measurements are consistent with expectations for the Standard Model Higgs boson
    corecore