4,772 research outputs found
The Comparison of Creatinine and Cystatin C Value in Preeclampsia Severity and Neonatal Outcome
Objectives: to compare the levels of creatinine and cystatin C with the severity of preeclampsia, and assess neonatal outcomes.Materials and Methods: Creatinine, cystatin C, and neonatal outcomes were assesed in 17 normotensive samples, 17 samples of mild preeclampsia and 17 samples of severe preeclampsia. Analysis of data with statistical tests of ANOVA and t test differences between 2 proportions.Results: The mean levels of creatinine in the normotensive group, mild preeclampsia, severe preeclampsia are 0.56 mg/dL, 0.67 mg/ dL, and 0.75 mg/dL, p=0.138; While on cystatin C are 0.82 mg/L, 1.03 mg/L and 1.32 mg/L, p=0.000. The adverse neonatal out-come wasn't found in the normotensive group. In mild pre-eclampsia obtained 1 preterm birth and 1 intrauterine fetal death (IUFD), whereas in severe preeclampsia obtained 3 babies born preterm, 1 IUFD, and 1 intrauterine growth restriction (IUGR).Conclusion: levels of cystatin C was increased significantly in line with increased severity of preeclampsia, whereas creatinine was not increased significantly. Cystatin C is better than crea-tinine as a marker of renal dysfunction in preeclampsia patients. There was an increase in adverse neonatal outcomes in the group of preeclampsia
Non-universal Casimir Effect in Saturated Superfluid He Films at T
Measurements of Casimir effects in He films in the vicinity of the bulk
superfluid transition temperature have been carried out, where
changes in the film thickness and the superfluid density are both monitored as
a function of temperature. The Kosterlitz-Thouless superfluid onset temperature
in the film is found to occur just as the Casimir dip in the film thickness
from critical fluctuations becomes evident. Additionally, a new film-thickening
effect is observed precisely at when the temperature is swept
extremely slowly. We propose that this is a non-universal Casimir effect
arising from the viscous suppression of second sound modes in the film.Comment: 5 pages, 6 figures, corrected an equation, small change to fit valu
An eigenfunction method for particle acceleration at ultra-relativistic shocks
We adapt and modify the eigenfunction method of computing the power-law
spectrum of particles accelerated at a relativistic shock front via the
first-order Fermi process (Kirk, J.G., Schneider, P., Astrophysical Journal
315, 425 (1987)) to apply to shocks of arbitrarily high Lorentz factor. The
power-law index of accelerated particles undergoing isotropic small-angle
scattering at an ultrarelativistic, unmagnetized shock is found to be s=4.23
+/- 0.2 (where s=d\ln f/ d\ln p, with f the Lorentz-invariant phase-space
density and p the momentum), in agreement with the results of Monte-Carlo
simulations. We present results for shocks in plasmas with different equations
of state and for Lorentz factors ranging from 5 to infinity.Comment: 4 pages, 2 figures, contribution to the Proceedings of the 5th
Huntsville GRB Symposiu
Particle Acceleration at Ultra-Relativistic Shocks and the Spectra of Relativistic Fireballs
We examine Fermi-type acceleration at relativistic shocks, and distinguish
between the initial boost of the first shock crossing cycle, where the energy
gain per particle can be very large, and the Fermi process proper with repeated
shock crossings, in which the typical energy gain is of order unity. We
calculate by means of numerical simulations the spectrum and angular
distribution of particles accelerated by this Fermi process, in particular in
the case where particle dynamics can be approximated as small-angle scattering.
We show that synchrotron emission from electrons or positrons accelerated by
this process can account remarkably well for the observed power-law spectra of
GRB afterglows and Crab-like supernova remnants. In the context of a
decelerating relativistic fireball, we calculate the maximum particle energy
attainable by acceleration at the external blast wave, and discuss the minimum
energy for this acceleration process and its consequences for the observed
spectrum.Comment: To appear in Proceedings of the 5th Huntsville Gamma-Ray Burst
Symposium. LaTeX, 6 pages, 2 figures, uses aipproc.sty and epsfi
Caecal diverticulitis presenting as acute appendicitis: a case report
Solitary caecal diverticulum is an uncommon entity and therefore difficult to diagnose except at surgery. Caecal diverticulitis is an infrequent cause of acute abdomen and usually presents in a manner similar to acute appendicitis. It is extremely difficult to differentiate it preoperative from acute appendicitis and such distinction is usually made in the operating room. The optimal management of this clinical condition is still controversial, ranging from conservative treatment with antibiotics to aggressive surgical resections
Neutrino Background Flux from Sources of Ultrahigh-Energy Cosmic-Ray Nuclei
Motivated by Pierre Auger Observatory results favoring a heavy nuclear
composition for ultrahigh-energy (UHE) cosmic rays, we investigate implications
for the cumulative neutrino background. The requirement that nuclei not be
photodisintegrated constrains their interactions in sources, therefore limiting
neutrino production via photomeson interactions. Assuming a injection spectrum and
photodisintegration via the giant dipole resonance, the background flux of
neutrinos is lower than if UHE nuclei ubiquitously survive in
their sources. This is smaller than the analogous Waxman-Bahcall flux for UHE
protons by about one order of magnitude, and is below the projected IceCube
sensitivity. If IceCube detects a neutrino background, it could be due to other
sources, e.g., hadronuclear interactions of lower-energy cosmic rays; if it
does not, this supports our strong restrictions on the properties of sources of
UHE nuclei.Comment: 7 pages, 3 figure
Element Diffusion in the Solar Interior
We study the diffusion of helium and other heavy elements in the solar
interior by solving exactly the set of flow equations developed by Burgers for
a multi-component fluid, including the residual heat-flow terms. No
approximation is made concerning the relative concentrations and no restriction
is placed on the number of elements considered. We give improved diffusion
velocities for hydrogen, helium, oxygen and iron, in the analytic form derived
previously by Bahcall and Loeb. These expressions for the diffusion velocities
are simple to program in stellar evolution codes and are expected to be
accurate to . Our complete treatment of element diffusion can be
directly incorporated in a standard stellar evolution code by means of an
exportable subroutine, but, for convenience, we also give simple analytical
fits to our numerical results.Comment: TeX document, 25 pages, for hardcopy with figures contact
[email protected]. Institute for Advanced Study number AST 93/1
APPLICATION OF FUZZY-MLP MODEL TO ULTRASONIC LIVER IMAGE CLASSIFICATION
In this paper, we propose the application of fuzzy-MLP in theclassification of ultrasonic liver images. The four sets of ultrasonic liverimages used in the experiment are: normal, liver cysts, alcoholic cirrhosisand carcinoma.To deal with the sample images efficiently, we extract textural features fromthe Pathology Bearing Regions (PBRs) of the ultrasound liver images. Theselected features for the classification are entropy, energy and maximumprobability-based texture features extracted using gray level co-occurrencematrix second-order statistics. The fuzzy-MLP model is constructed for theselected features classify various categories of ultrasonic liver images.The efficacy of Fuzzy-MLP model and conventional artificial neural network(ANN) has been compared on the basis of the same feature vector. A testwith 82 training data and 110 test data for all the four classes shows 92.73%classification accuracy for the proposed fuzzy-MLP model. It is comparedwith the 81.82% counterpart provided by conventional ANN method
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