2,039 research outputs found
Track train dynamics analysis and test program: Methodology development for the derailment safety analysis of six-axle locomotives
The operational safety of six axle locomotives is analyzed. A locomotive model with corresponding data on suspension characteristics, a method of track defect characterization, and a method of characterizing operational safety are used. A user oriented software package was developed as part of the methodology and was used to study the effect (on operational safety) of various locomotive parameters and operational conditions such as speed, tractive effort, and track curvature. The operational safety of three different locomotive designs was investigated
Nonequilibrium static growing length scales in supercooled liquids on approaching the glass transition
The small wavenumber behavior of the structure factor of
overcompressed amorphous hard-sphere configurations was previously studied for
a wide range of densities up to the maximally random jammed state, which can be
viewed as a prototypical glassy state [A. Hopkins, F. H. Stillinger and S.
Torquato, Phys. Rev. E, 86, 021505 (2012)]. It was found that a precursor to
the glassy jammed state was evident long before the jamming density was reached
as measured by a growing nonequilibrium length scale extracted from the volume
integral of the direct correlation function , which becomes long-ranged
as the critical jammed state is reached. The present study extends that work by
investigating via computer simulations two different atomic models: the
single-component Z2 Dzugutov potential in three dimensions and the
binary-mixture Kob-Andersen potential in two dimensions. Consistent with the
aforementioned hard-sphere study, we demonstrate that for both models a
signature of the glass transition is apparent well before the transition
temperature is reached as measured by the length scale determined from from the
volume integral of the direct correlation function in the single-component case
and a generalized direct correlation function in the binary-mixture case. The
latter quantity is obtained from a generalized Orstein-Zernike integral
equation for a certain decoration of the atomic point configuration. We also
show that these growing length scales, which are a consequence of the
long-range nature of the direct correlation functions, are intrinsically
nonequilibrium in nature as determined by an index that is a measure of
deviation from thermal equilibrium. It is also demonstrated that this
nonequilibrium index, which increases upon supercooling, is correlated with a
characteristic relaxation time scale.Comment: 26 pages, 14 figure
Level-1 jet trigger hardware for the ALICE electromagnetic calorimeter at LHC
The ALICE experiment at the LHC is equipped with an electromagnetic
calorimeter (EMCal) designed to enhance its capabilities for jet measurement.
In addition, the EMCal enables triggering on high energy jets. Based on the
previous development made for the Photon Spectrometer (PHOS) level-0 trigger, a
specific electronic upgrade was designed in order to allow fast triggering on
high energy jets (level-1). This development was made possible by using the
latest generation of FPGAs which can deal with the instantaneous incoming data
rate of 26 Gbit/s and process it in less than 4 {\mu}s.Comment: proceeding of TWEPP-10 at Aachen. 6 pages, 4 figure
Application of regulatory sequence analysis and metabolic network analysis to the interpretation of gene expression data
We present two complementary approaches for the interpretation of clusters of
co-regulated genes, such as those obtained from DNA chips and related methods.
Starting from a cluster of genes with similar expression profiles, two basic
questions can be asked:
1. Which mechanism is responsible for the coordinated transcriptional response
of the genes? This question is approached by extracting motifs that are shared
between the upstream sequences of these genes. The motifs extracted are putative
cis-acting regulatory elements.
2. What is the physiological meaning for the cell to express together these
genes? One way to answer the question is to search for potential metabolic
pathways that could be catalyzed by the products of the genes. This can be
done by selecting the genes from the cluster that code for enzymes, and trying
to assemble the catalyzed reactions to form metabolic pathways.
We present tools to answer these two questions, and we illustrate their use with
selected examples in the yeast Saccharomyces cerevisiae. The tools are available
on the web (http://ucmb.ulb.ac.be/bioinformatics/rsa-tools/;
http://www.ebi.ac.uk/research/pfbp/; http://www.soi.city.ac.uk/~msch/)
Efficiency of spinal anesthesia versus general anesthesia for lumbar spinal surgery: a retrospective analysis of 544 patients.
BACKGROUND: Previous studies have shown varying results in selected outcomes when directly comparing spinal anesthesia to general in lumbar surgery. Some studies have shown reduced surgical time, postoperative pain, time in the postanesthesia care unit (PACU), incidence of urinary retention, postoperative nausea, and more favorable cost-effectiveness with spinal anesthesia. Despite these results, the current literature has also shown contradictory results in between-group comparisons.
MATERIALS AND METHODS: A retrospective analysis was performed by querying the electronic medical record database for surgeries performed by a single surgeon between 2007 and 2011 using procedural codes 63030 for diskectomy and 63047 for laminectomy: 544 lumbar laminectomy and diskectomy surgeries were identified, with 183 undergoing general anesthesia and 361 undergoing spinal anesthesia (SA). Linear and multivariate regression analyses were performed to identify differences in blood loss, operative time, time from entering the operating room (OR) until incision, time from bandage placement to exiting the OR, total anesthesia time, PACU time, and total hospital stay. Secondary outcomes of interest included incidence of postoperative spinal hematoma and death, incidence of paraparesis, plegia, post-dural puncture headache, and paresthesia, among the SA patients.
RESULTS: SA was associated with significantly lower operative time, blood loss, total anesthesia time, time from entering the OR until incision, time from bandage placement until exiting the OR, and total duration of hospital stay, but a longer stay in the PACU. The SA group experienced one spinal hematoma, which was evacuated without any long-term neurological deficits, and neither group experienced a death. The SA group had no episodes of paraparesis or plegia, post-dural puncture headaches, or episodes of persistent postoperative paresthesia or weakness.
CONCLUSION: SA is effective for use in patients undergoing elective lumbar laminectomy and/or diskectomy spinal surgery, and was shown to be the more expedient anesthetic choice in the perioperative setting
1947 To Congratulate You Card
A card reading To Congratulate You to Louis-Philippe Gagné from J. B. Marcotte and family.https://digitalcommons.usm.maine.edu/fac-lpg-1947-01-03/1030/thumbnail.jp
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