Evaluation of trends in organ dysfunction in critically ill patients may help predict outcome.
To determine the usefulness of repeated measurement the Sequential Organ Failure Assessment (SOFA) score ...for prediction of mortality in intensive care unit (ICU) patients.
Prospective, observational cohort study conducted from April 1 to July 31, 1999.
A 31-bed medicosurgical ICU at a university hospital in Belgium.
Three hundred fifty-two consecutive patients (mean age, 59 years) admitted to the ICU for more than 24 hours for whom the SOFA score was calculated on admission and every 48 hours until discharge.
Initial SOFA score (0-24), Delta-SOFA scores (differences between subsequent scores), and the highest and mean SOFA scores obtained during the ICU stay and their correlations with mortality.
The initial, highest, and mean SOFA scores correlated well with mortality. Initial and highest scores of more than 11 or mean scores of more than 5 corresponded to mortality of more than 80%. The predictive value of the mean score was independent of the length of ICU stay. In univariate analysis, mean and highest SOFA scores had the strongest correlation with mortality, followed by Delta-SOFA and initial SOFA scores. The area under the receiver operating characteristic curve was largest for highest scores (0.90; SE, 0.02; P<.001 vs initial score). When analyzing trends in the SOFA score during the first 96 hours, regardless of the initial score, the mortality rate was at least 50% when the score increased, 27% to 35% when it remained unchanged, and less than 27% when it decreased. Differences in mortality were better predicted in the first 48 hours than in the subsequent 48 hours. There was no significant difference in the length of stay among these groups. Except for initial scores of more than 11 (mortality rate >90%), a decreasing score during the first 48 hours was associated with a mortality rate of less than 6%, while an unchanged or increasing score was associated with a mortality rate of 37% when the initial score was 2 to 7 and 60% when the initial score was 8 to 11.
Sequential assessment of organ dysfunction during the first few days of ICU admission is a good indicator of prognosis. Both the mean and highest SOFA scores are particularly useful predictors of outcome. Independent of the initial score, an increase in SOFA score during the first 48 hours in the ICU predicts a mortality rate of at least 50%.
Muon Radiography or muography is based on the measurement of the absorption or scattering of cosmic muons, as they pass through the interior of large scale bodies, In particular, absorption muography ...has been applied to investigate the presence of hidden cavities inside the pyramids or underground, as well as the interior of volcanoes’ edifices. The MURAVES project has the challenging aim of investigating the density distribution inside the summit of Mt. Vesuvius. The information, together with that coming from gravimetric measurements, is useful as input to models, to predict how an eruption may develop. The MURAVES apparatus is a robust and low power consumption muon telescope consisting of an array of three identical and independent muon trackers, which provide in a modular way a total sensitive area of three square meters. Each tracker consists of four doublets of planes of plastic scintillator bars with orthogonal orientation, optically coupled to Silicon photomultipliers for the readout of the signal. The muon telescope has been installed on the slope of the volcano and has collected a first set of data, which are being analyzed.
Ionization cooling is the preferred method for producing bright muon beams. This cooling technique requires the operation of normal conducting, radio-frequency (rf) accelerating cavities within the ...multi-tesla fields of dc solenoid magnets. Under these conditions, cavities exhibit increased susceptibility to rf breakdown, which can damage cooling channel components and imposes limits on channel length and transmission efficiency. We report, for the first time, stable high-vacuum, normal-conducting cavity operation at gradients of50MV/min an external magnetic field of three tesla, through the use of beryllium cavity elements. This eliminates a significant technical risk that has previously been inherent in ionization cooling channel designs.
Three-Dimensional Structure of a Purple Lipoxygenase Skrzypczak-Jankun, Ewa; Bross, Rebecca A; Carroll, Richard T ...
Journal of the American Chemical Society,
11/2001, Letnik:
123, Številka:
44
Journal Article
Recenzirano
Polyunsaturated fatty acid metabolism is governed primarily by two enzymes, prostaglandin H synthase and lipoxygenase. The crystal structure of the metastable product-oxidized purple form of soybean ...lipoxygenase-3 was determined at 2.0 Å resolution. The data reveal that the chromophore corresponds to an iron-peroxide complex, a potential intermediate in the catalyzed reaction. A significant alteration of the iron site accompanies the formation of the complex. The structure, the first for a fatty acid-lipoxygenase complex, also reveals an unexpected mode of binding, and identifies amino acid residues that may play significant roles in catalysis, regio- and stereoselectivity.
Based on theoretical perspectives from the work/family literature, this study tested a model for examining expatriate families' adjustment while on global assignments as an antecedent to expatriates' ...adjustment to working in a host country. Data were collected from 110 families that had been relocated for global assignments. Longitudinal data, assessing family characteristics before the assignment and cross-cultural adjustment approximately 6 months into the assignment, were coded. This study found that family characteristics (family support, family communication, family adaptability) were related to expatriates' adjustment to working in the host country. As hypothesized, the families' cross-cultural adjustment mediated the effect of family characteristics on expatriates' host-country work adjustment.
Charged-particle tracking in the international Muon Ionisation Cooling Experiment (MICE) will be performed using two solenoidal spectrometers, each instrumented with a tracking detector based on ...350μm diameter scintillating fibres. The design and construction of the trackers is described along with the quality-assurance procedures, photon-detection system, readout electronics, reconstruction and simulation software and the data-acquisition system. Finally, the performance of the MICE tracker, determined using cosmic rays, is presented.
The muographic imaging of volcanoes relies on the measured transmittance of the atmospheric muon flux through the target. An important bias affecting the result comes from background contamination ...mimicking a higher transmittance. The MU‐RAY and TOMUVOL collaborations measured independently in 2013 the atmospheric muon flux transmitted through the Puy de Dôme volcano using their early prototype detectors, based on plastic scintillators and on Glass Resistive Plate Chambers, respectively. These detectors had three (MU‐RAY) or four (TOMUVOL) detection layers of 1 m2 each, tens (MU‐RAY) or hundreds (TOMUVOL) of nanosecond time resolution, a few millimeter position resolution, an energy threshold of few hundreds MeV, and no particle identification capabilities. The prototypes were deployed about 1.3 km away from the summit, where they measured, behind rock depths larger than 1000 m, remnant fluxes of 1.83±0.50(syst)±0.07(stat) m−2 d−1 deg−2 (MU‐RAY) and 1.95±0.16(syst)±0.05(stat) m−2 d−1 deg−2 (TOMUVOL), that roughly correspond to the expected flux of high‐energy atmospheric muons crossing 600 meters water equivalent (mwe) at 18° elevation. This implies that imaging depths larger than 500 mwe from 1 km away using such prototype detectors suffer from an overwhelming background. These measurements confirm that a new generation of detectors with higher momentum threshold, time‐of‐flight measurement, and/or particle identification is needed. The MU‐RAY and TOMUVOL collaborations expect shortly to operate improved detectors, suitable for a robust muographic imaging of kilometer‐scale volcanoes.
Key Point
The feasibility of muon imaging of km thick volcanoes was checked using two different detectors
The MU-RAY project: Volcano radiography with cosmic-ray muons Ambrosi, G.; Ambrosino, F.; Battiston, R. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
02/2011, Letnik:
628, Številka:
1
Journal Article
Recenzirano
Cosmic-ray muon radiography is a technique for imaging the variation of density inside the top few 100
m of a volcanic cone. With resolutions up to 10s of meters in optimal detection conditions, muon ...radiography can provide images of the top region of a volcano edifice with a resolution that is considerably better than that typically achieved with conventional methods. Such precise measurements are expected to provide us with information on anomalies in the rock density distribution, like those expected from dense lava conduits, low density magma supply paths or the compression with depth of the overlying soil. The MU-RAY project aims at the construction of muon telescopes and the development of new analysis tools for muon radiography. The telescopes are required to be able to work in harsh environment and to have low power consumption, good angular and time resolutions, large active area and modularity. The telescope consists of two
X–
Y planes of 2×2 square meters area made by plastic scintillator strips of triangular shape. Each strip is read by a fast WLS fiber coupled to a silicon photomultiplier. The readout electronics is based on the SPIROC chip.