524 research outputs found
Spectral Variations in Early-Type Galaxies as a Function of Mass
We report on the strengths of three spectral indicators - Mg_2, Hbeta, and
Hn/Fe - in the integrated light of a sample of 100 field and cluster E/S0
galaxies. The measured indices are sensitive to age and/or and metallicity
variations within the galaxy sample. Using linear regression analysis for data
with non-uniform errors, we determine the intrinsic scatter present among the
spectral indices of our galaxy sample as a function of internal velocity
dispersion. Our analysis indicates that there is significantly more intrinsic
scatter in the two Balmer line indices than in the Mg_2 index, indicating that
the Balmer indices provide more dynamic range in determining the age of a
stellar population than does the Mg_2 index. Furthermore, the scatter is much
larger for the low velocity dispersion galaxies, indicating that star formation
has occurred more recently in the lower mass galaxies.Comment: 4 pages, 1 figure, 1 table, to appear in the Astrophysical Journal
Letter
University of Vermont Community Tobacco Use and Attitudes Survey
Introduction: Smoking remains an important public health issue in U.S. Colleges. 17.3% of U.S. smokers are 18-24 years old. 28% of U.S. college students began smoking at age 19 or older. Currently 1,104 U.S. Colleges have adopted Tobacco-Free policies.https://scholarworks.uvm.edu/comphp_gallery/1216/thumbnail.jp
Inpatient costs, mortality and 30-day re-admission in patients with central-line-associated bloodstream infections
AbstractPrevious work has suggested that central-line-associated bloodstream infection (CLABSI) is associated with increased costs and risk of mortality; however, no studies have looked at both total and variable costs, and information on outcomes outside of the intensive-care unit (ICU) is sparse. The aim of this study was to determine the excess in-hospital mortality and costs attributable to CLABSI in ICU and non-ICU patients. We conducted a retrospective cohort and cost-of-illness study from the hospital perspective of 398 patients at a tertiary-care academic medical centre from 1 January 2008 to 31 December 2010. All CLABSI patients and a simple random sample drawn from a list of all central lines inserted during the study period were included. Generalized linear models with log link and gamma distribution were used to model costs as a function of CLABSI and important covariates. Costs were adjusted to 2010 US dollars by use of the personal consumption expenditures for medical care index. We used multivariable logistic regression to identify independent predictors of in-hospital mortality. Among both ICU and non-ICU patients, adjusted variable costs for patients with CLABSI were c. $32 000 (2010 US dollars) higher on average than for patients without CLABSI. After we controlled for severity of illness and other healthcare-associated infections, CLABSI was associated with a 2.27-fold (95% CI 1.15–4.46) increased risk of mortality. Other healthcare-associated infections were also significantly associated with greater costs and mortality. Overall, CLABSI was associated with significantly higher adjusted in-hospital mortality and total and variable costs than those for patients without CLABSI
A survey to investigate the association of pain, foot disability and quality of life with corns
Background
Corns are a common foot problem affecting a large proportion of the population. This study describes the characteristics of corns experienced by 201 participants taking part in a randomised controlled trial to investigate associations between demographic and corn parameters on pain, foot related disability and quality of life (QoL).
Methods
Pain from the main (index) corn was measured using a visual analogue scale (VAS); foot related disability was assessed with the Foot Disability Questionnaire (now known as the Manchester Foot Pain and Disability Index) and quality of life was recorded with the EQ-5D questionnaire. The effect of demographic and corn parameters on the pain and quality of life outcomes was assessed with analysis of variance (ANOVA) methods. The effect of the same factors on a linear combination of the foot-related disability outcome measures was assessed using multivariate ANOVA methods. Pain was also tested for its mediating properties on the causal pathway between the independent variables and quality of life.
Results
The mean pain score was 5.29 points on a 10 cm VAS, with females reporting substantively higher pain levels than males. Age affected foot-related disability, with lower levels on all domains of the MFPDI reported in older participants; each year of advancing age was associated with falls of: 0.009 points on the Concern about Appearance (CA) domain; 0.047 points on the Functional Limitation (FL) domain and 0.048 points on the Pain Intensity (PI) domain. Sex and corn type also affected disability, with higher scores reported by females and participants with plantar corns.
Conclusions
The effect of pain was shown to mediate the relationship between sex and foot-related disability. The presence of plantar corns has a more detrimental effect on QoL than dorsal/inter-digital corns
Polarization instabilities in a two-photon laser
We describe the operating characteristics of a new type of quantum oscillator
that is based on a two-photon stimulated emission process. This two-photon
laser consists of spin-polarized and laser-driven K atoms placed in a
high-finesse transverse-mode-degenerate optical resonator, and produces a beam
with a power of 0.2 W at a wavelength of 770 nm. We observe
complex dynamical instabilities of the state of polarization of the two-photon
laser, which are made possible by the atomic Zeeman degeneracy. We conjecture
that the laser could emit polarization-entangled twin beams if this degeneracy
is lifted.Comment: Accepted by Physical Review Letters. REVTeX 4 pages, 4 EPS figure
Canine pseudopregnancy: an evaluation of prevalence and current treatment protocols in the UK
Background: There is a dearth of literature on pseudopregnancy in the bitch, with only a few treatment-based
studies published since the 1990s. Pseudopregnancy may be under-recognised in bitches and may account for a
proportion of behavioural cases seen in veterinary practices including aggression. Little is known about commonly
used treatments for overtly pseudopregnant bitches and it is possible that current regimes may not be prescribed
for a sufficient duration to control any clinical signs including, physical and behavioural changes. To investigate
current trends in diagnosis and treatment of canine pseudopregnancy, a postal survey was sent to 2000 randomly
selected veterinary surgeons in UK veterinary practices. The questionnaire queried how often vets recognise cases
of pseudopregnancy in spayed and entire bitches, which physical or behavioural signs are commonly recognised
for diagnosis, and which management or treatment protocols are used.
Results: The response rate was 19.8% (397/2000). Ninety-six percent of veterinary surgeons reported seeing
pseudopregnant bitches showing behavioural changes without any physical changes within the last 12 months.
Of those behavioural changes, collecting and mothering objects was the most frequently reported behavioural
sign (96%). Ninety-seven percent of vets had seen aggression in pseudopregnant bitches. Nevertheless, only 52%
of vets routinely asked owners about behavioural changes during consultations. Forty-nine percent of respondents
reported seeing pseudopregnancy in spayed bitches. The most commonly reported physical sign was enlarged
mammary glands and/or milk production (89%). Treatment options varied (surgical, medical or none) and depended on
duration and severity of physical and behavioural signs, owners’ preference, cost, concurrent disease, drug availability
and previous history.
Conclusions: This is the largest epidemiological study of canine pseudopregnancy in the UK. The prevalence and
severity of clinical signs in dogs with pseudopregnancy are variable and possibly under-estimated. Dogs with overt
pseudopregnancy experience diverse physical and behavioural changes and information on standard treatment
protocols are lacking. Although, progress on our understanding of diagnosis and treatment of pseudopregnancy in
spayed and entire bitches has been made, further studies are warranted
Facilitating the analysis of a UK national blood service supply chain using distributed simulation
In an attempt to investigate blood unit ordering policies, researchers have created a discrete-event model of the UK National Blood Service (NBS) supply chain in the Southampton area of the UK. The model has been created using Simul8, a commercial-off-the-shelf discrete-event simulation package (CSP). However, as more hospitals were added to the model, it was discovered that the length of time needed to perform a single simulation severely increased. It has been claimed that distributed simulation, a technique that uses the resources of many computers to execute a simulation model, can reduce simulation runtime. Further, an emerging standardized approach exists that supports distributed simulation with CSPs. These CSP Interoperability (CSPI) standards are compatible with the IEEE 1516 standard The High Level Architecture, the defacto interoperability standard for distributed simulation. To investigate if distributed simulation can reduce the execution time of NBS supply chain simulation, this paper presents experiences of creating a distributed version of the CSP Simul8 according to the CSPI/HLA standards. It shows that the distributed version of the simulation does indeed run faster when the model reaches a certain size. Further, we argue that understanding the relationship of model features is key to performance. This is illustrated by experimentation with two different protocols implementations (using Time Advance Request (TAR) and Next Event Request (NER)). Our contribution is therefore the demonstration that distributed simulation is a useful technique in the timely execution of supply chains of this type and that careful analysis of model features can further increase performance
Regulation of HSP27 on NF-κB pathway activation may be involved in metastatic hepatocellular carcinoma cells apoptosis
<p>Abstract</p> <p>Background</p> <p>During the process of metastasis, cells are subjected to various apoptotic stimuli. Aberrant expression of apoptotic regulators often contribute to cell metastasis. Heat shock protein 27(HSP27) is confirmed as an apoptosis regulator, but its antiapoptotic mechanism in metastatic hepatocellular carcinoma (HCC) cells remains unclear.</p> <p>Methods</p> <p>Levels of HSP27 protein and its phosphorylation in Hep3B, MHCC97L to MHCC97H cells with different metastatic potentials were determined by western blot analysis. MHCC97H cells were transfected with specific small interference RNA (siRNA) against HSP27. The <it>in vitro </it>migration and invasion potentials of cells were evaluated by Transwell assay. The apoptosis ratio of MHCC97H cells was analyzed by TUNEL staining and Flow Cytometry. Alteration of signal transduction pathway after HSP27 knockdown in MHCC97H cells was evaluated through a Human Q Series Signal Transduction in Cancer Gene Array analysis. Nuclear NF-κB contentration and endogenous IKK activity were demonstrated by ELISA assay. The association of IKKα, IKKβ, IκBα with HSP27 and the association between IKKβ and IKKα in MHCC97H cells were determined by co-immunoprecipitation assay followed by western blot analysis.</p> <p>Results</p> <p>HSP27 protein and its phosphorylation increased in parallel with enhanced metastatic potentials of HCC cells. siRNA-mediated HSP27 knockdown in MHCC97H significantly suppressed cells migration and invasion <it>in vitro </it>and induced cell apoptosis; the prominently altered signal transduction pathway was NF-κB pathway after HSP27 knockdown in MHCC97H cells. Furthermore, inhibition of HSP27 expression led to a significant decrease of nuclear NF-κB contentration and endogenous IKK activity. In addition, HSP27 was associated with IKKα, IKKβ, IκBα in three HCC cells above. ELISA assay and western blot analysis also showed a decrease of the association between IKKβ and IKKα, the association between phosphor-HSP27 and IKK complex, and an increase of total IκBα but reducing tendency of phosphor-IκBα when HSP27 expression was efficiently knocked down in MHCC97H cells.</p> <p>Conclusion</p> <p>Altogether, these findings revealed a possible effect of HSP27 on apoptosis in metastatic HCC cells, in which HSP27 may regulate NF-kB pathway activation.</p
Search for the lepton-family-number nonconserving decay \mu -> e + \gamma
The MEGA experiment, which searched for the muon- and electron-number
violating decay \mu -> e + \gamma, is described. The spectrometer system, the
calibrations, the data taking procedures, the data analysis, and the
sensitivity of the experiment are discussed. The most stringent upper limit on
the branching ratio of \mu -> e + \gamma) < 1.2 x 10^{-11} was obtained
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