1,153 research outputs found
Alkali metal for ultraviolet band-pass filter
An alkali metal filter having a layer of metallic bismuth deposited onto the alkali metal is provided. The metallic bismuth acts to stabilize the surface of the alkali metal to prevent substantial surface migration from occurring on the alkali metal, which may degrade optical characteristics of the filter. To this end, a layer of metallic bismuth is deposited by vapor deposition over the alkali metal to a depth of approximately 5 to 10 A. A complete alkali metal filter is described along with a method for fabricating the alkali metal filter
Simultaneous UV and X-ray Spectroscopy of the Seyfert 1 Galaxy NGC 5548. I. Physical Conditions in the UV Absorbers
We present new UV spectra of the nucleus of the Seyfert 1 galaxy NGC 5548,
which we obtained with the Space Telescope Imaging Spectrograph at high
spectral resolution, in conjunction with simultaneous Chandra X-ray Observatory
spectra. Taking advantage of the low UV continuum and broad emission-line
fluxes, we have determined that the deepest UV absorption component covers at
least a portion of the inner, high-ionization narrow-line region (NLR). We find
nonunity covering factors in the cores of several kinematic components, which
increase the column density measurements of N V and C IV by factors of 1.2 to
1.9 over the full-covering case; however, the revised columns have only a minor
effect on the parameters derived from our photoionization models. For the first
time, we have simultaneous N V and C IV columns for component 1 (at -1040
km/s), and find that this component cannot be an X-ray warm absorber, contrary
to our previous claim based on nonsimultaneous observations. We find that
models of the absorbers based on solar abundances severely overpredict the O VI
columns previously obtained with the Far Ultraviolet Spectrograph, and present
arguments that this is not likely due to variability. However, models that
include either enhanced nitrogen (twice solar) or dust, with strong depletion
of carbon in either case, are successful in matching all of the observed ionic
columns. These models result in substantially lower ionization parameters and
total column densities compared to dust-free solar-abundance models, and
produce little O VII or O VIII, indicating that none of the UV absorbers are
X-ray warm absorbers.Comment: 33 pages, 5 figures (Figures 3 and 4 are in color), Accepted for
publication in the Astrophysical Journa
Functional studies of the kidney of living animals using multicolor 2-photon microscopy
Optical microscopy, when applied to living animals, provides a powerful means of studying cell biology in the most physiologically relevant setting. The ability of two-photon microscopy to collect optical sections deep into biological tissues has opened up the field of intravital microscopy to high-resolution studies of the brain, lens, skin, and tumors. Here we present examples of the way in which two-photon microscopy can be applied to intravital studies of kidney physiology. Because the kidney is easily externalized without compromising its function, microscopy can be used to evaluate various aspects of renal function in vivo. These include cell vitality and apoptosis, fluid transport, receptor-mediated endocytosis, blood flow, and leukocyte trafficking. Efficient two-photon excitation of multiple fluorophores permits comparison of multiple probes and simultaneous characterization of multiple parameters and yields spectral information that is crucial to the interpretation of images containing uncharacterized autofluorescence. The studies described here demonstrate the way in which two-photon microscopy can provide a level of resolution previously unattainable in intravital microscopy, enabling kinetic analyses and physiological studies of the organs of living animals with subcellular resolution
The Role of Discrete Emotions in Job Satisfaction: A Meta-Analysis
[Summary] The relationship between emotions and job satisfaction is widely acknowledged via affective events theory (AET). Despite its widespread use, AET was not designed to address why specific emotions might differentially relate to job satisfaction. We utilize appraisal theory of emotion to refine AET and provide this nuanced theorizing. We metaâanalytically test our ideas with 235 samples across 99â883 individuals and 22â600 intraâindividual episodes. We test two approachesâspecific emotion experiences (16 discrete emotions) versus general emotion experiences (positive or negative emotions)âand present empirical evidence of their similarities and differences with job satisfaction. Our findings suggest that specific emotions with circumstanceâagency appraisals (e.g., depression and happiness) have the strongest associations with job satisfaction compared to emotions with selfâ and otherâagency appraisals and general emotion experiences. However, more variability is observed for negative emotions and job satisfaction compared to positive emotions. Further, we address and even challenge influential critiques of emotions and job satisfaction via a metaâanalytic test of five moderatorsâemotion intensity versus frequency, target of emotion, job satisfaction measure, level of analysis, and time referent for emotion and job satisfaction recall. In sum, we advance academic and practitioner understanding of the relationship between emotions and job satisfaction
Conversion Efficacy and Safety of Intravenous Ibutilide Compared With Intravenous Procainamide in Patients With Atrial Flutter or Fibrillation 11This study was sponsored by Pharmacia & Upjohn, Kalamazoo, Michigan.22See Appendix Afor a complete list of investigators and study sites.
AbstractObjectives. This multicenter study compared the efficacy and safety of ibutilide versus procainamide for conversion of recent-onset atrial flutter or fibrillation.Background. Ibutilide fumarate is an intravenous (IV) class III antiarrhythmic agent that has been shown to be significantly more effective than placebo in the pharmacologic conversion of atrial flutter and fibrillation to sinus rhythm. Procainamide is commonly used for conversion of recent-onset atrial fibrillation to normal sinus rhythm.Methods. One hundred twenty-seven patients (age range 22 to 92 years) with atrial flutter or fibrillation of 3 h to 90 daysâ (mean 21 days) duration were randomized to receive either two 10-min IV infusions of 1 mg of ibutilide fumarate, separated by a 10-min infusion of 5% dextrose in sterile water, or three successive 10-min IV infusions of 400 mg of procainamide hydrochloride.Results. Of the 127 patients, 120 were evaluated for efficacy: 35 (58.3%) of 60 in the ibutilide group compared with 11 (18.3%) of 60 in the procainamide group had successful termination within 1.5 h of treatment (p < 0.0001). Seven patients were found to have violated the protocol and were not included in the final evaluation. In the patients with atrial flutter, ibutilide had a significantly higher success rate than procainamide (76% [13 of 17] vs. 14% [3 of 22], p = 0.001). Similarly, in the atrial fibrillation group, ibutilide had a significantly higher success rate than procainamide (51% [22 of 43] vs. 21% [8 of 38], p = 0.005). One patient who received ibutilide, which was found to be a protocol violation, had sustained polymorphic ventricular tachycardia requiring direct current cardioversion. Seven patients who received procainamide became hypotensive.Conclusions. This study establishes the superior efficacy of ibutilide over procainamide when administered to patients to convert either atrial fibrillation or atrial flutter to sinus rhythm. Hypotension was the major adverse effect seen with procainamide. A low incidence of serious proarrhythmia was seen with the administration of ibutilide occurring at the end of infusion
Society of pediatric liver transplantation: Current registry status 2011â2018
BackgroundSPLIT was founded in 1995 in order to collect comprehensive prospective data on pediatric liver transplantation, including waiting list data, transplant, and early and late outcomes. Since 2011, data collection of the current registry has been refined to focus on prospective data and outcomes only after transplant to serve as a foundation for the future development of targeted clinical studies.ObjectiveTo report the outcomes of the SPLIT registry from 2011 to 2018.MethodsThis is a multicenter, crossâsectional analysis characterizing patients transplanted and enrolled in the SPLIT registry between 2011 and 2018. All patients, <18Â years of age, received a first liverâonly, a combined liverâkidney, or a combined liverâpancreas transplant during this study period.ResultsA total of 1911 recipients from 39 participating centers in North America were registered. Indications included biliary atresia (38.5%), metabolic disease (19.1%), tumors (11.7%), and fulminant liver failure (11.5%). Greater than 50% of recipients were transplanted as either Status 1A/1B or with a MELD/PELD exception score. Incompatible transplants were performed in 4.1%. KaplanâMeier estimates of 1âyear patient and graft survival were 97.3% and 96.6%. First 30Â days of surgical complications included reoperation (31.7%), hepatic artery thrombosis (6.3%), and portal vein thrombosis (3.2%). In the first 90Â days, biliary tract complications were reported in 13.6%. Acute cellular rejection during first year was 34.7%. At 1 and 2Â years of followâup, 39.2% and 50.6% had normal liver tests on monotherapy (tacrolimus or sirolimus). Further surgical, survival, allograft function, and complications are detailed.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/153657/1/petr13605_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/153657/2/petr13605.pd
FANCJ compensates for RAP80 deficiency and suppresses genomic instability induced by interstrand cross-links
FANCJ, a DNA helicase and interacting partner of the tumor suppressor BRCA1, is crucial for the repair of DNA interstrand crosslinks (ICL), a highly toxic lesion that leads to chromosomal instability and perturbs normal transcription. In diploid cells, FANCJ is believed to operate in homologous recombination (HR) repair of DNA double-strand breaks (DSB); however, its precise role and molecular mechanism is poorly understood. Moreover, compensatory mechanisms of ICL resistance when FANCJ is deficient have not been explored. In this work, we conducted a siRNA screen to identify genes of the DNA damage response/DNA repair regime that when acutely depleted sensitize FANCJ CRISPR knockout cells to a low concentration of the DNA cross-linking agent mitomycin C (MMC). One of the top hits from the screen was RAP80, a protein that recruits repair machinery to broken DNA ends and regulates DNA end-processing. Concomitant loss of FANCJ and RAP80 not only accentuates DNA damage levels in human cells but also adversely affects the cell cycle checkpoint, resulting in profound chromosomal instability. Genetic complementation experiments demonstrated that both FANCJ\u27s catalytic activity and interaction with BRCA1 are important for ICL resistance when RAP80 is deficient. The elevated RPA and RAD51 foci in cells co-deficient of FANCJ and RAP80 exposed to MMC are attributed to single-stranded DNA created by Mre11 and CtIP nucleases. Altogether, our cell-based findings together with biochemical studies suggest a critical function of FANCJ to suppress incompletely processed and toxic joint DNA molecules during repair of ICL-induced DNA damage
Characterization of the emitting and absorbing media around the nucleus of the active galaxy UGC11763 using XMM-Newton data
Aims. The detailed analysis of all data taken by the XMM-Newton satellite of
UGC11763 to characterize the different components that are emitting and
absorbing radiation in the vicinity of the active nucleus.
Methods. The continuum emission was studied through the EPIC spectra taking
profit of the spectral range of these cameras. The high resolution RGS spectra
were analyzed in order to characterize the absorbing features and the emission
line features that arise in the spectra of this source.
Results. A power law with a photon index \Gamma = 1.72^{+0.03}_{-0.01}
accounts for the continuum emission of this source in the hard X-rays from 10
down to 1 keV. At lower energies, a black body model with kT= 0.100\pm 0.003
keV provides a good description of the observed soft excess. The absorption
signatures in the spectra of UGC11763 are consistent with the presence of a two
phase ionized material (log U=1.65^{+0.07}_{-0.08}; 2.6\pm 0.1 and log N_{H} =
21.2\pm 0.2; 21.51\pm 0.01 cm^{-2}, respectively) in the line of sight. The
physical conditions found are consistent with the two phases being in pressure
equilibrium. The low ionization component is more ionized than typically found
for warm absorbers in other Seyfert 1 galaxies. There are also signatures of
some emission lines: Ovii He(r), Ovii He(f), a blend of the
Neix He triplet and Fexviii at \lambda 17.5 \AA.Comment: 11 pages, 10 figures, accepted to be published by A&
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Power and Authority in Eastern Christian Experience: Papers of the Sophia Institute Academic Conference New York, December 2010
The essays in this volume were delivered at the Third Annual Conference of the Sophia Institute in December 2010 at Union Theological Seminary in New York City. The theme of that conference, âPower and Authority in Eastern Christian Experience,â brought forth a diverse group of scholars who contributed their perspectives on the ways the Eastern Orthodox Church, in its broadest sense, has negotiated the notions of power, authority, (dis)obedience, and resistance over time and space. These insightful essays promise to draw the Orthodox world into a dynamic and productive discourse
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