164 research outputs found
Optimized methods to measure acetoacetate, 3-hydroxybutyrate, glycerol, alanine, pyruvate, lactate and glucose in human blood using a centrifugal analyser with a fluorimetric attachment
Optimized methods are described for the analysis of glucose, lactate, pyruvate, alanine, glycerol, D-3-hydroxybutyrate and acetoacetate in perchloric acid extracts of human blood using the Cobas Bio centrifugal analyser. Glucose and lactate are measured using the photometric mode and other metabolites using the fluorimetric mode. The intra-assay coefficients of variation ranged from 0.7 to 4.1%, except with very low levels of pyruvate and acetoacetate where the coefficients of variation were 7.1 and 12% respectively. All seven metabolites can be measured in a perchloric acid extract of 20 μl of blood. The methods have been optimized with regard to variation in the perchloric acid content of the samples. These variations arise from the method of sample preparation used to minimize changes occurring in metabolite concentration after venepuncture
SuperWASP: Wide Angle Search for Planets
SuperWASP is a fully robotic, ultra-wide angle survey for planetary transits.
Currently under construction, it will consist of 5 cameras, each monitoring a
9.5 x 9.5 deg field of view. The Torus mount and enclosure will be fully
automated and linked to a built-in weather station. We aim to begin
observations at the beginning of 2003.Comment: 4 pages, 1 figure, to be published in proceedings of "Scientific
Frontiers in Research on Extrasolar Planets
Current Status of the SuperWASP Project
We present the current status of the SuperWASP project, a Wide Angle Search
for Planets. SuperWASP consists of up to 8 individual cameras using ultra-wide
field lenses backed by high-quality passively cooled CCDs. Each camera covers
7.8 x 7.8 sq degrees of sky, for nearly 500 sq degrees of sky coverage.
SuperWASP I, located in LaPalma, is currently operational with 5 cameras and is
conducting a photometric survey of a large numbers of stars in the magnitude
range ~7 to 15. The collaboration has developed a custom-built reduction
pipeline and aims to achieve better than 1 percent photometric precision. The
pipeline will also produce well sampled light curves for all the stars in each
field which will be used to detect: planetary transits, optical transients, and
track Near-Earth Objects. Status of current observations, and expected rates of
extrasolar planetary detections will be presented. The consortium members,
institutions, and further details can be found on the web site at:
http://www.superwasp.org.Comment: 3 pages, 2 figures, submitted to the Proceedings of the 13th Cool
Stars Workshop, Ed. F. Favata, ESA-S
Impact of Laws Aimed at Healthcare-Associated Infection Reduction: A Qualitative Study
Background: Healthcare-associated infections (HAIs) are preventable. Globally, laws aimed at reducing HAIs have been implemented. In the USA, these laws are at the federal and state levels. It is not known whether the state interventions are more effective than the federal incentives alone. Objective: The aims of this study were to explore the impact federal and state HAI laws have on state departments of health and hospital stakeholders in the USA and to explore similarities and differences in perceptions across states. Methods: A qualitative study was conducted. In 2012, we conducted semistructured interviews with key stakeholders from states with and without state-level laws to gain multiple perspectives. Interviews were transcribed and open coding was conducted. Data were analysed using content analysis and collected until theoretical saturation was achieved. Results: Ninety interviews were conducted with stakeholders from 12 states (6 states with laws and 6 states without laws). We found an increase in state-level collaboration. The publicly reported data helped hospitals benchmark and focus leaders on HAI prevention. There were concerns about the publicly reported data (eg, lack of validation and timeliness). Resource needs were also identified. No major differences were expressed by interviewees from states with and without laws. Conclusions: While we could not tease out the impact of specific interventions, increased collaboration between departments of health and their partners is occurring. Harmonisation of HAI definitions and reporting between state and federal laws would minimise reporting burden. Continued monitoring of the progress of HAI prevention is needed
New periodic variable stars coincident with ROSAT sources discovered using SuperWASP
We present optical lightcurves of 428 periodic variable stars coincident with ROSAT X-ray sources, detected using the first run of the SuperWASP photometric survey. Only 68 of these were previously recognised as periodic variables. A further 30 of these objects are previously known pre-main sequence stars, for which we detect a modulation period for the first time. Amongst the newly identified periodic variables, many appear to be close eclipsing binaries, their X-ray emission is presumably the result of RS CVn type behaviour. Others are probably BY Dra stars, pre-main sequence stars and other rapid rotators displaying enhanced coronal activity. A number of previously catalogued pulsating variables (RR Lyr stars and Cepheids) coincident with X-ray sources are also seen, but we show hat these are likely to be misclassifications. We identify four objects which are probable low mass eclipsing binary stars, based on
their very red colour and light curve morphology
Distances, ages, and epoch of formation of globular clusters
We review the results on distances and absolute ages of galactic globular
clusters (GCs) obtained after the release of the Hipparcos catalogue. Several
methods for the Population II local distance scale are discussed, exploiting
NEW RESULTS for RR Lyraes in the Large Magellanic Cloud (LMC). We find that the
so-called Short and Long Distance Scales may be reconciled whether a consistent
reddening scale is adopted for Cepheids and RR Lyrae variables in the LMC.
Distances and ages for the 9 clusters discussed in Paper I are re-derived using
an enlarged sample of local subdwarfs, which includes about 90% of the
metal-poor dwarfs with accurate parallaxes (Delta p/p < 0.12) in the whole
Hipparcos catalogue. On average, our revised distance moduli are decreased by
0.04 mag with respect to Paper I. The corresponding age of the GCs is
t=11.5+-2.6 Gyr (95% confidence range). The relation between Mv(ZAHB) and
metallicity for the nine programme clusters turns out to be
Mv(ZAHB)=(0.18+-0.09)([Fe/H]+1.5)+(0.53+-0.12).Thanks to Hipparcos the major
contribution to the total error budget associated with the subdwarf fitting
technique has been moved from parallaxes to photometric calibrations, reddening
and metallicity scale. This total uncertainty still amounts to about +-0.12
mag. Comparing the corresponding (true) LMC distance modulus 18.64+-0.12 mag
with other existing determinations, we conclude that at present the best
estimate for the distance of the LMC is: 18.54+-0.03+-0.06, suggesting that
distances from the subdwarf fitting method are 1 sigma too long. Consequently,
our best estimate for the age of the GCs is revised to: Age = 12.9+-2.9 Gyr
(95% confidence range). The best relation between Mv(ZAHB) and [Fe/H] is:
Mv(ZAHB) =(0.18+-0.09)([Fe/H]+1.5)+(0.63+-0.07).Comment: 76 pages, 6 encapsulated figures and 6 tables. Latex, uses
aasms4.sty. Revised and improved version, with new data on field RR Lyraes in
LMC. Accepted in the Astrophysical Journa
The Age Of Globular Clusters In Light Of Hipparcos: Resolving the Age Problem?
We review five independent techniques which are used to set the distance
scale to globular clusters, including subdwarf main sequence fitting utilizing
the recent Hipparcos parallax catalogue. These data together all indicate that
globular clusters are farther away than previously believed, implying a
reduction in age estimates. This new distance scale estimate is combined with a
detailed numerical Monte Carlo study designed to assess the uncertainty
associated with the theoretical age-turnoff luminosity relationship in order to
estimate both the absolute age and uncertainty in age of the oldest globular
clusters. Our best estimate for the mean age of the oldest globular clusters is
now Gyr, with a one-sided, 95% confidence level lower limit of
9.5 Gyr. This represents a systematic shift of over 2 compared to our
earlier estimate, due completely to the new distance scale---which we emphasize
is not just due to the Hipparcos data. This now provides a lower limit on the
age of the universe which is consistent with either an open universe, or a
flat, matter dominated universe (the latter requiring H_0 \le 67 \kmsmpc).
Our new study also explicitly quantifies how remaining uncertainties in the
distance scale and stellar evolution models translate into uncertainties in the
derived globular cluster ages. Simple formulae are provided which can be used
to update our age estimate as improved determinations for various quantities
become available.Comment: 41 pages, including 10 eps figs, uses aaspp4.sty and flushrt.sty,
submitted to Ap.J., revised to incorporate FULL Hipparcos catalogue dat
Optimization of a Morphing Wing Based on Coupled Aerodynamic and Structural Constraints
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/77091/1/AIAA-39016-101.pd
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