1,305 research outputs found
Accessing the distribution of linearly polarized gluons in unpolarized hadrons
Gluons inside unpolarized hadrons can be linearly polarized provided they
have a nonzero transverse momentum. The simplest and theoretically safest way
to probe this distribution of linearly polarized gluons is through cos(2 phi)
asymmetries in heavy quark pair or dijet production in electron-hadron
collisions. Future Electron-Ion Collider (EIC) or Large Hadron electron
Collider (LHeC) experiments are ideally suited for this purpose. Here we
estimate the maximum asymmetries for EIC kinematics.Comment: 4 pages, 2 figures, to appear in the proceedings of the XIX
International Workshop on Deep Inelastic Scattering and Related Subjects (DIS
2011), Newport News, VA, USA, 11-15 April 201
The Line Emission Region in III Zw 2: Kinematics and Variability
We have studied the Ly-al, Hbeta, Halpha and Mg II2798 line profiles of the
Seyfert 1 galaxy III Zw 2. The shapes of these broad emission lines show
evidence of a multicomponent origin and also features which may be identified
as the peaks due to a rotating disk. We have proposed a two-component Broad
Line Region (BLR) model consisting of an inner Keplerian relativistic disk and
an outer structure surrounding the disk. The results of the fitting of the four
Broad Emission Lines (BELs) here considered, are highly consistent in both the
inner and outer component parameters. Adopting a mass of approx. 2 E8 sollar
masses for the central object we found that the outer radius of the disk is
approximately equal for the four considered lines (approx 0.01 pc). However,
the inner radius of the disk is not the same: 0.0018 pc for Ly-alpha, 0.0027 pc
for Mg II, and 0.0038 pc for the Balmer lines. This as well as the relatively
broad component present in the blue wings of the narrow [OIII] lines indicate
stratification in the emission-line region. Using long-term Hbeta observations
(1972-1990, 1998) we found a flux variation of the BEL with respect to the
[OIII] lines.Comment: ApJ, accepted, 22 pages, 10 figure
The UV Properties of the Narrow Line Quasar I Zwicky 1
I Zw 1 is the prototype narrow line quasar. We report here the results of our
study of the UV emission of I Zw 1 using a high S/N (50-120) spectrum obtained
with the HST FOS. The following main new results are obtained: 1. The Mg II and
Al III doublets are partially/fully resolved. The measured doublet ratios
verify theoretical predictions that the lines are thermalized in the BLR. 2. A
weak associated UV absorption system is detected in N~V, and possibly also in C
IV and Lya, suggesting an outflow with a velocity of 1870 km/s and velocity
dispersion <300 km/s. 3. Lines from ions of increasing ionization level show
increasing excess blue wing flux, and an increasing line peak velocity shift,
reaching a maximum blueshift of about 2000 km/s for He II 1640. This may
indicate an out-flowing component in the BLR, where the ionization level
increases with velocity, and which is visible only in the approaching
direction. The highest velocity part of this outflow may produce the associated
UV absorption system. 4. The small C III] 1909 EW, and the small C III]
1909/Lya and C III] 1909/Si III] 1892 flux ratios indicate a typical BLR
density of 10^11, i.e. about an order of magnitude larger than implied by C
III] 1909 in most quasars. A BLR component of a higher density is implied by
the EW and doublet ratio of the Al III 1857 doublet. 5. Prominent Fe II UV 191
emission is seen, together with weaker line emission at 1294 and 1871 A. These
three features have been proposed as evidence for significant Lya pumping of
the 8-10 eV levels of Fe II. 6. Significant Fe III emission is present. The Fe
III UV 34 and UV 48 multiplets are clearly resolved, and Fe III UV 1, UV 47, UV
50, and UV 68 may also be present. (Shortened version)Comment: 28 pages, 1 table and 7 figures included. Uses aas2pp4.sty. Scheduled
for the Astrophysical Journal November 10, 1997 issue, Vol. 48
Follow-up of colorectal cancer patients: quality of life and attitudes towards follow-up.
The aims of our study were to assess the effect of follow-up on the quality of life of colorectal cancer patients and to assess the attitudes of patients towards follow-up as a function of patient characteristics. Patients who had been treated with curative intent were selected from four types of hospitals. Eighty-two patients were interviewed using a structured questionnaire, whereas 130 patients received the questionnaire by mail. To assess the effect of follow-up on the quality of life, the interviewed patients were randomly allocated to three groups and interviewed at different times in relation to the follow-up visit. Analysis did not show an effect of the follow-up visit on quality of life. Patients reported a positive attitude towards follow-up: it reassured them, they judged the communication with the physician to be positive, and they experienced only slight nervous anticipation and few other disadvantages. Patients reported a strong preference for follow-up, and a large majority would prefer follow-up even if it would not lead to earlier detection of a recurrence. Apart from living situation, no patient characteristics were clearly associated with the attitude towards follow-up. Implications for clinical practice are discussed
Translational and Regulatory Challenges for Exon Skipping Therapies
Several translational challenges are currently impeding the therapeutic development of antisense-mediated exon skipping approaches for rare diseases. Some of these are inherent to developing therapies for rare diseases, such as small patient numbers and limited information on natural history and interpretation of appropriate clinical outcome measures. Others are inherent to the antisense oligonucleotide (AON)-mediated exon skipping approach, which employs small modified DNA or RNA molecules to manipulate the splicing process. This is a new approach and only limited information is available on long-term safety and toxicity for most AON chemistries. Furthermore, AONs often act in a mutation-specific manner, in which case multiple AONs have to be developed for a single disease. A workshop focusing on preclinical development, trial design, outcome measures, and different forms of marketing authorization was organized by the regulatory models and biochemical outcome measures working groups of Cooperation of Science and Technology Action: "Networking towards clinical application of antisense-mediated exon skipping for rare diseases." The workshop included participants from patient organizations, academia, and members of staff from the European Medicine Agency and Medicine Evaluation Board (the Netherlands). This statement article contains the key outcomes of this meeting.status: publishe
Banff lesions and renal allograft survival in chronic-active antibody mediated rejection
Aims: Chronic-active antibody mediated rejection (c-aABMR) is a major cause of kidney graft loss. Currently, little is known about the relation between histopathologic parameters and renal allograft survival. Methods and results: Between 2008 and 2014, 41 patients with a progressive decrease in renal function were diagnosed with c-aABMR according to Banff 2015 and followed up for at least 3 years. Clinical and renal biopsy characteristics were analyzed for association with graft survival. During follow-up 26 cases lost their graft because of c-aABMR at a median follow up of 40 months after diagnosis. Cases with v-lesions in their biopsy had a significant higher loss of eGFR prior to diagnosis. The total inflammation score (r = −0.45 p =.007) and the severity of interstitial fibrosis (r = −0.38 p =.023) were related to the eGFR at time of biopsy. Univariate regression analysis showed that eGFR at time of biopsy, total inflammation, interstitial fibrosis and the sum chronicity score were significantly related to the risk for graft failure during follow-up. In a multivariate analysis only the severity of interstitial fibrosis remained associated with decreased graft survival (HR 1.9 per score point, 95% CI 1.2–2.8, p =.004). Conclusion: Severity of renal interstitial fibrosis and not inflammation predicts graft survival in cases of c-aABMR
Design and rationale of DISCOVER global registry in type 2 diabetes:Real-world insights of treatment patterns and its relationship with cardiovascular, renal, and metabolic multimorbidities
10.1016/j.jdiacomp.2021.108077Journal of Diabetes and its Complications351210807
Data-driven dissection of emission-line regions in Seyfert galaxies
Indirectly resolving the line-emitting gas regions in distant Active Galactic
Nuclei (AGN) requires both high-resolution photometry and spectroscopy (i.e.
through reverberation mapping). Emission in AGN originates on widely different
scales; the broad-line region (BLR) has a typical radius less than a few
parsec, the narrow-line region (NLR) extends out to hundreds of parsecs. But
emission also appears on large scales from heated nebulae in the host galaxies
(tenths of kpc).
We propose a novel, data-driven method based on correlations between
emission-line fluxes to identify which of the emission lines are produced in
the same kind of emission-line regions. We test the method on Seyfert galaxies
from the Sloan Digital Sky Survey (SDSS) Data Release 7 (DR7) and Galaxy Zoo
project.
We demonstrate the usefulness of the method on Seyfert-1s and Seyfert-2
objects, showing similar narrow-line regions (NLRs). Preliminary results from
comparing Seyfert-2s in spiral and elliptical galaxy hosts suggest that the
presence of particular emission lines in the NLR depends both on host
morphology and eventual radio-loudness. Finally, we explore an apparent linear
relation between the final correlation coefficient obtained from the method and
time lags as measured in reverberation mapping for Zw229-015.Comment: Accepted into Astronomy & Astrophysic
Short-term emission line and continuum variations in Mrk110
We present results of a variability campaign of Mrk110 performed with the
9.2-m Hobby-Eberly Telescope (HET) at McDonald Observatory. The high S/N
spectra cover most of the optical range. They were taken from 1999 November
through 2000 May. The average interval between the observations was 7.3 days
and the median interval was only 3.0 days. Mrk110 is a narrow-line Seyfert 1
galaxy. During our campaign the continuum flux was in a historically low stage.
Considering the delays of the emission lines with respect to the continuum
variations we could verify an ionization stratification of the BLR. We derived
virial masses of the central black hole from the radial distances of the
different emission lines and from their widths. The calculated central masses
agree within 20%. Furthermore, we identified optical HeI singlet emission lines
emitted in the broad-line region. The observed line fluxes agree with
theoretical predictions. We show that a broad wing on the red side of the
[OIII]5007 line is caused by the HeI singlet line at 5016A.Comment: 11 pages, 16 figures, A&A Latex. Accepted for publication in A&A Main
Journa
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