52 research outputs found
The Geometry and Kinematics of the Broad-Line Region in NGC 5548 from HST and IUE Observations
The spatial and radial velocity distribution of broad-line-emitting gas in the Seyfert 1 galaxy NGC 5548 is examined through the process of reverberation mapping, which is done by detailed comparison of continuum and emission-line variations. Recent spectroscopic monitoring of NGC 5548 with HST and IUE allows us to resolve the transfer function (TF) that relates the continuum and emission-line variability. We also examine the radial velocity-resolved TFs, and confirm that predominantly radial motions of the line-emitting clouds can be excluded. We find that a broad-line region comprised of clouds that are orbiting a central source of mass ~108 M☉ along randomly inclined Keplerian orbits and irradiated by a beamed continuum source yields a TF and line profile that are qualitatively consistent with the observations. In this model, the clouds that produce the variable C IV emission lie within 12 lt-days of the central source, and the continuum radiation is confined to a wide biconical beam (semi-opening angle 35°-60°) with the observer viewing into the cone
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Multi-omic association study identifies DNA methylation-mediated genotype and smoking exposure effects on lung function in children living in urban settings
Impaired lung function in early life is associated with the subsequent development of chronic respiratory disease. Most genetic associations with lung function have been identified in adults of European descent and therefore may not represent those most relevant to pediatric populations and populations of different ancestries. In this study, we performed genome-wide association analyses of lung function in a multiethnic cohort of children (n = 1,035) living in low-income urban neighborhoods. We identified one novel locus at the TDRD9 gene in chromosome 14q32.33 associated with percent predicted forced expiratory volume in one second (FEV1) (p = 2.4x10-9; βz = -0.31, 95% CI = -0.41- -0.21). Mendelian randomization and mediation analyses revealed that this genetic effect on FEV1 was partially mediated by DNA methylation levels at this locus in airway epithelial cells, which were also associated with environmental tobacco smoke exposure (p = 0.015). Promoter-enhancer interactions in airway epithelial cells revealed chromatin interaction loops between FEV1-associated variants in TDRD9 and the promoter region of the PPP1R13B gene, a stimulator of p53-mediated apoptosis. Expression of PPP1R13B in airway epithelial cells was significantly associated the FEV1 risk alleles (p = 1.3x10-5; β = 0.12, 95% CI = 0.06–0.17). These combined results highlight a potential novel mechanism for reduced lung function in urban youth resulting from both genetics and smoking exposure
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Biomarkers and Noncalcified Coronary Artery Plaque Progression in Older Men Treated With Testosterone.
ObjectiveRecent results from the Cardiovascular Trial of the Testosterone Trials showed that testosterone treatment of older men with low testosterone was associated with greater progression of noncalcified plaque (NCP). We evaluated the effect of anthropometric measures and cardiovascular biomarkers on plaque progression in individuals in the Testosterone Trial.MethodsThe Cardiovascular part of the trial included 170 men aged 65 years or older with low testosterone. Participants received testosterone gel or placebo gel for 12 months. The primary outcome was change in NCP volume from baseline to 12 months, as determined by coronary computed tomography angiography (CCTA). We assayed several markers of cardiovascular risk and analyzed each marker individually in a model as predictive variables and change in NCP as the dependent variable.ResultsOf 170 enrollees, 138 (73 testosterone, 65 placebo) completed the study and were available for the primary analysis. Of 10 markers evaluated, none showed a significant association with the change in NCP volume, but a significant interaction between treatment assignment and waist-hip ratio (WHR) (P = 0.0014) indicated that this variable impacted the testosterone effect on NCP volume. The statistical model indicated that for every 0.1 change in the WHR, the testosterone-induced 12-month change in NCP volume increased by 26.96 mm3 (95% confidence interval, 7.72-46.20).ConclusionAmong older men with low testosterone treated for 1 year, greater WHR was associated with greater NCP progression, as measured by CCTA. Other biomarkers and anthropometric measures did not show statistically significant association with plaque progression
Playing on common ground: Spaces of sport, education and corporate connectivity, contestation and creativity
In this article we examine connectivities within the ‘messy’ organizational commons of sport, education and corporate partnerships. As scholars forewarn, there are currently key stakeholders within the commons that that have set agendas, occupied ideological and physical terrain, and legitimized a presence and authority. The intertwining of organizations here is an evident function of an increased symbiosis between sport, education and governmental and non-governmental stakeholders to carve out significant sector spaces, and exert authority and power over the creation, implementation and ownership ‘collaborative’ and intersectional work. Drawing on spatial theorists, Henri Lefebvre and Yi Fu Tuan, and examples from FIFA and the IOC, we present a conceptual framework of global stakeholder relations. Focusing of processes of thought, production and action, we offer an intersectional critique of the nuances of Sport–Corporate–Education nexus and consider possibilities and potential for sport education spaces to be reconfigured ane
Polymorphism in chlordiazepoxide: crystal chemistry, particle morphology and structural aspects of phase inter-conversion.
The Geometry and Kinematics of the Broad-Line Region in NGC 5548 from HST and IUE Observations
The spatial and radial velocity distribution of broad-line-emitting gas in the Seyfert 1 galaxy NGC 5548 is examined through the process of reverberation mapping, which is done by detailed comparison of continuum and emission-line variations. Recent spectroscopic monitoring of NGC 5548 with HST and IUE allows us to resolve the transfer function (TF) that relates the continuum and emission-line variability. We also examine the radial velocity-resolved TFs, and confirm that predominantly radial motions of the line-emitting clouds can be excluded. We find that a broad-line region comprised of clouds that are orbiting a central source of mass ~108 M☉ along randomly inclined Keplerian orbits and irradiated by a beamed continuum source yields a TF and line profile that are qualitatively consistent with the observations. In this model, the clouds that produce the variable C IV emission lie within 12 lt-days of the central source, and the continuum radiation is confined to a wide biconical beam (semi-opening angle 35°-60°) with the observer viewing into the cone
Intravitreal bevacizumab in the treatment of vasoproliferative retinal tumours
AIM: To evaluate the efficacy of intravitreal bevacizumab in the treatment of retinal vasoproliferative tumours (VPT). MATERIALS AND METHODS: Six eyes of 6 patients with VPT who received intravitreal bevacizumab were retrospectively reviewed. All patients received between one and three injections of intravitreal bevacizumab depending upon response to treatment. Best-corrected visual acuity (BCVA), tumour size, and presence of co-pathology or sequelae were noted pre- and postoperatively and then analysed. Subsequent retreatments were performed in patients with recurrent or persistent VPT according to the ophthalmologist's discretion. Retreatments included photodynamic therapy with verteporfin, ruthenium-106 plaque brachytherapy, or endoresection of tumour. RESULTS: The mean follow-up duration was 33.3 months (range 10–66 months). At baseline, the mean logMAR BCVA was 1.45 (Snellen equivalent of 6/165); range 0.10–1.90 (6/8—CF). Following bevacizumab treatment the mean logMAR BCVA was 0.98 (Snellen equivalent of 6/57); range 0.5–1.9 (Snellen equivalent of 6/19 to CF). Therefore, there was no statistically significant change in visual acuity. The mean tumour thickness reduced from 2.4 to 2.1 mm following treatment with bevacizumab. However, this did not reach the statistical significance of P<0.05. Despite the visual improvement following bevacizumab therapy, five out of six patients had recurrence of tumour activity during the follow-up period and required further intervention in order to achieve sustained regression. CONCLUSIONS: Intravitreal bevacizumab appeared to result in temporary reduction of tumour thickness in 3 out of 6 VPT patients. However, neither the reduction in tumour thickness nor the change in visual acuity were statistically significant and intravitreal bevacizumab monotherapy had limited effectiveness in causing long-term regression of the lesions. Additional therapy was indicated in five out of six patients to establish long-term regression. The efficacy of bevacizumab as an adjunct is as yet undetermined and further studies are needed. Presently, we recommend other treatment modalities in the long-term management of VPTs
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