165 research outputs found
Two Particle Azimuthal Correlations in 4.2A GeV C+Ta Collisions
Two particle azimuthal correlations are studied in 4.2A GeV C+Ta collisions
observed with the 2-m propane bubble chamber exposed at JINR Dubna
Synchrophasotron. The correlations are analyzed both for protons and negative
pions, and their dependence on the collision centrality, rapidity and rapidity
difference is investigated. It is found that protons show a weak back-to-back
correlations, while a side-by-side correlations are observed for negative
pions. Restricting both protons to the target or projectile fragmentation
region, the side-by-side correlations are observed for protons also. Using the
two particle correlation function, the flow analysis is performed and intensity
of directed flow is determined without event-by event estimation of the
reaction plane.Comment: 4 pages, 3 figure
Strong-field approximation for intense-laser atom processes: the choice of gauge
The strong-field approximation can be and has been applied in both length
gauge and velocity gauge with quantitatively conflicting answers. For
ionization of negative ions with a ground state of odd parity, the predictions
of the two gauges differ qualitatively: in the envelope of the angular-resolved
energy spectrum, dips in one gauge correspond to humps in the other. We show
that the length-gauge SFA matches the exact numerical solution of the
time-dependent Schr\"odinger equation.Comment: 5 pages, 3 figures, revtex
Outbreak of West Nile virus infection among humans in Serbia, August to October 2012
We describe the first reported outbreak of West Nile virus (WNV) infection in humans in Serbia in August to October 2012 and examine the association of various variables with encephalitis and fatal outcome. Enzyme-linked immunosorbent assay (ELISA) was used for detection of WNV-specific IgM and IgG antibodies in sera and cerebrospinal fluid. A total of 58 patients (mean age: 61 years; standard deviation: 15) were analysed: 44 were from Belgrade and its suburbs; 52 had neuroinvasive disease, of whom 8 had meningitis, while 44 had encephalitis. Acute flaccid paralysis developed in 13 of the patients with encephalitis. Age over 60 years and immunosuppression (including diabetes) were independently associated with the development of encephalitis in a multivariate analysis: odds ratio (OR): 44.8 (95% confidence interval (CI): 4.93-408.59); p=0.001 (age over 60 years); OR: 10.76 (95% CI: 1.06-109.65); p=0.045 (immunosuppression including diabetes). Respiratory failure requiring mechanical ventilation developed in 13 patients with encephalitis. A total of 35 patients had completely recovered by the time they were discharged; nine patients died. The presence of acute flaccid paralysis, consciousness impairment, respiratory failure and immunosuppression (without diabetes) were found to be associated with death in hospital in a univariate analysis (p lt 0.001, p=0.007, p lt 0.001 and p=0.010, respectively)
Seasonality of trichinellosis in patients hospitalized in Belgrade, Serbia
A retrospective study of the course and outcome of trichinellosis in a series of 50 patients hospitalized at the Institute for Infectious and Tropical Diseases in Belgrade between 2001 and 2008 was performed. Clinical diagnosis of trichinellosis was based upon the patients' clinical history, symptoms and signs, and eosinophilia. The occurrence of cases showed a strong seasonality (P lt 0.00011. The incubation period ranged between one and 33 days. The mean time between onset of symptoms and admission was nine days. Family outbreaks were the most frequent. Smoked pork products were the dominant source of infection (76 %). Fever was the most frequent clinical manifestation (90 %), followed by myalgia (80 %) and periorbital edema (76 %). 43 patients were examined serologically and 72 % of them had anti-Trichinella antibodies. Eosinophilia and elevated levels of serum CK and LDH were detected in 94, 50 and 56 % of the patients, respectively. All patients responded favorably to treatment with mebendazole or albendazole, but eight developed transient complications. Trichinellosis remains a major public health issue in Serbia
Aerosol route as a feasible bottom-up chemical approach for up-converting phosphor particles processing
The opportunities of the hot wall aerosol synthesis, i.e. conventional spray pyrolysis (CSP) method are demonstrated for the generation of highly spherical three-dimensional (3D) nanostructured phosphor particles with uniformly distributed components, phases and nano-clustered inner structure. With the presumption that certain particle morphology is formed during the evaporation/drying stage, the aerosol transport properties and powder generation are correlated with the particles structural and morphological features. With the help of various analyzing techniques like Field Emission Scanning Electron Microscopy (FE-SEM), Transmission Electron Microscopy (TEM) coupled with energy dispersive X-ray Analysis and STEM mode (TEM/EDS), X-ray Powder Diffraction (XRPD) and fluorescence measurements the feasible processing of up-conversion rare-earth Y2O3:Er, Yb phosphors powders are discussed.This is the peer-reviewed version of the paper:Dugandžić, I., Lojpur, V., Mančić, L., Dramićanin, M.D., Rabanal, M.E., Hashishin, T., Tan, Z., Ohara, S., Milošević, O., 2013. Aerosol route as a feasible bottom-up chemical approach for upconverting phosphor particles processing. Advanced Powder Technology (Special Issue Featuring Articles from ICCCI2012), 24, 852–857. [https://doi.org/10.1016/j.apt.2013.02.011
Nonleptonic decays and the Skyrme model
Nonleptonic decay branching ratios are estimated by means of the
QCD enhanced effective weak Hamiltonian supplemented by the SU(3) Skyrme model
used to estimate the nonperturbative matrix elements. The model has only one
free parameter, namely the Skyrme charge , which is fixed through the
experimental values of the octet-decuplet mass splitting and the
axial coupling constant . The whole scheme is equivalent to that which
works well for the nonleptonic hyperon decays. The ratios of calculated
amplitudes are in agreement with experiment. However, the absolute values are
about twice too large if short-distance corrections and only ground
intermediate states are included.Comment: 4 pages, 1 figure, 1 table, version to appear in Phys.Rev.
Vortex structure of thin mesoscopic disks in the presence of an inhomogeneous magnetic field
The vortex states in a thin mesoscopic disk are investigated within the
phenomenological Ginzburg-Landau theory in the presence of different ''model''
magnetic field profiles with zero average field which may result from a
ferromagnetic disk or circulating currents in a loop near the superconductor.
We calculated the dependences of both the ground and metastable states on the
magnitude and shape of the magnetic field profile for different values of the
order parameter angular moment, i.e. the vorticity. The regions of existence of
the multi-vortex state and the giant vortex state are found. We analysed the
phase transitions between these states and studied the contribution from
ring-shaped vortices. A new transition between different multi-vortex
configurations as the ground state is found. Furthermore, we found a vortex
state consisting of a central giant vortex surrounded by a collection of
anti-vortices which are located in a ring around this giant vortex. The limit
to a disk with an infinite radius, i.e. a film, will also be discussed. We also
extended our results to ''real'' magnetic field profiles and to the case in
which an external homogeneous magnetic field is present.Comment: 17 pages, 23 figures. Submitted to PR
Relativistic treatment of harmonics from impurity systems in quantum wires
Within a one particle approximation of the Dirac equation we investigate a
defect system in a quantum wire. We demonstrate that by minimally coupling a
laser field of frequency omega to such an impurity system, one may generate
harmonics of multiples of the driving frequency. In a multiple defect system
one may employ the distance between the defects in order to tune the cut-off
frequency.Comment: 9 pages Latex, 8 eps figures, section added, numerics improve
Leptonic and charged kaon decay modes of the meson measured in heavy-ion collisions at the CERN SPS
We report a measurement of meson production in central Pb+Au
collisions at E/A=158 GeV. For the first time in heavy-ion collisions,
mesons were reconstructed in the same experiment both in the KK
and the dilepton decay channel. Near mid-rapidity, this yields rapidity
densities, corrected for production at the same rapidity value, of 2.05 +-
0.14(stat) +- 0.25(syst) and 2.04 +- 0.49(stat)+-{0.32}(syst), respectively.
The shape of the measured transverse momentum spectra is also in close
agreement in both decay channels. The data rule out a possible enhancement of
the yield in the leptonic over the hadronic channel by a factor larger
than 1.6 at 95% CL.Comment: 11 pages, 4 figures,submitted to Phys. Rev. Let
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