5,709 research outputs found
QGP Susceptibilities from PNJL Model
An improved version of the PNJL model is used to calculate various
thermodynamical quantities, {\it viz.}, quark number susceptibility, isospin
susceptibility, specific heat, speed of sound and conformal measure. Comparison
with Lattice data is found to be encouraging.Comment: 4 pages, 2 figures, poster presented at Quark Matter'0
Virulence potential of Candida albicans isolated from oral cavity of patients with chronic renal failure on hemodialysis
Objective In patients with chronic renal failure (PCRF), the frequency of colonization of the oral cavity by yeasts of genus Candida spp. is high compared with healthy individuals. These yeasts have virulence factors that may contribute to the persistence of colonization and the development of these infections. The aim of this study was evaluate aspects of virulence from Candida albicans isolated from oral cavity of PCRF on dialysis.
Methods This study was initially conducted with 49 clinical samples of C. albicans. The virulence factors assayed were produce of biofilm, germ tube, determination of adherence in oral epithelial cells and evaluation of resistance to the antimicrobial action of neutrophils and mononuclear cells.
Results All isolates were highly efficient in forming biofilms on poly- styrene microplates, where 94% of the samples formed 4 + biofilm. Used as a screening test, of which three isolates were selected with different degrees of ability to form biofilm to assess other indicators of virulence. Overall, the isolates exhibited different characteristics regarding the virulence factors analyzed. It was also observed that the hypophosphorous acid (HOCl), production, one of leading inflammatory mediators with fungicidal action, also varied especially when the neutrophils, and not mononuclear cells, were stimulated with different samples. (Figure 1).
Conclusion Therefore, our results indicate that C. albicans, is not only the most common species in the oral cavity of CRFP on dialysis, but also it presents the main virulence attributes, which reinforces the importance of monitoring of these patients towards the prevention of fungal infections
Thermodynamics of two-colour QCD and the Nambu Jona-Lasinio model
We investigate two-flavour and two-colour QCD at finite temperature and
chemical potential in comparison with a corresponding Nambu and Jona-Lasinio
model. By minimizing the thermodynamic potential of the system, we confirm that
a second order phase transition occurs at a value of the chemical potential
equal to half the mass of the chiral Goldstone mode. For chemical potentials
beyond this value the scalar diquarks undergo Bose condensation and the diquark
condensate is nonzero. We evaluate the behaviour of the chiral condensate, the
diquark condensate, the baryon charge density and the masses of scalar diquark,
antidiquark and pion, as functions of the chemical potential. Very good
agreement is found with lattice QCD (N_c=2) results. We also compare with a
model based on leading-order chiral effective field theory.Comment: 24 pages, 12 figure
The CMS RPC gas gain monitoring system: an overview and preliminary results
The status of the CMS RPC Gas Gain Monitoring (GGM) system developed at the
Frascati Laboratory of INFN (Istituto Nazionale di Fisica Nucleare) is reported
on. The GGM system is a cosmic ray telescope based on small RPC detectors
operated with the same gas mixture used by the CMS RPC system. The GGM gain and
efficiency are continuously monitored on-line, thus providing a fast and
accurate determination of any shift in working point conditions. The
construction details and the first result of GGM commissioning are described.Comment: 8 pages, 9 figures, uses lnfprepCMS.sty, presented by L. Benussi at
RPC07, Mumbai, INDIA 200
Gas Analysis and Monitoring Systems for the RPC Detector of CMS at LHC
The Resistive Plate Chambers (RPC) detector of the CMS experiment at the LHC
proton collider (CERN, Switzerland) will employ an online gas analysis and
monitoring system of the freon-based gas mixture used. We give an overview of
the CMS RPC gas system, describe the project parameters and first results on
gas-chromatograph analysis. Finally, we report on preliminary results for a set
of monitor RPC.Comment: 9 pages, 8 figures. Presented by Stefano Bianco (Laboratori Nazionali
di Frascati dell'INFN) at the IEEE NSS, San Diego (USA), October 200
Design and Vertical Tests of SPS-series Double-Quarter Wave (DQW) Cavity Prototypes for the HL-LHC Crab Cavity System
Crab crossing is essential for high-luminosity colliders. The High Luminosity
Large Hadron Collider (HL-LHC) will equip one of its Interaction Points (IP1)
with Double-Quarter Wave (DQW) crab cavities. A DQW cavity is a new generation
of deflecting RF cavities that stands out for its compactness and broad
frequency separation between fundamental and first high-order modes. The
deflecting kick is provided by its fundamental mode. Each HL-LHC DQW cavity
shall provide a nominal deflecting voltage of 3.4 MV, although up to 5.0 MV may
be required. A Proof-of-Principle (PoP) DQW cavity was limited by quench at 4.6
MV. This paper describes a new, highly optimized cavity, designated DQW
SPS-series, which satisfies dimensional, cryogenic, manufacturing and impedance
requirements for beam tests at SPS and operation in LHC. Two prototypes of this
DQW SPS-series were fabricated by US industry and cold tested after following
conventional SRF surface treatment. Both units outperformed the PoP cavity,
reaching a deflecting voltage of 5.3-5.9 MV. This voltage - the highest reached
by a DQW cavity - is well beyond the nominal voltage of 3.4 MV and may even
operate at the ultimate voltage of 5.0MVwith sufficient margin. This paper
covers fabrication, surface preparation and cryogenic RF test results and
implications
Fluctuations as probe of the QCD phase transition and freeze-out in heavy ion collisions at LHC and RHIC
We discuss the relevance of higher order moments of net baryon number
fluctuations for the analysis of freeze-out and critical conditions in heavy
ion collisions at LHC and RHIC. Using properties of O(4) scaling functions, we
discuss the generic structure of these higher moments at vanishing baryon
chemical potential and apply chiral model calculations to explore their
properties at non-zero baryon chemical potential. We show that the ratios of
the sixth to second and eighth to second order moments of the net baryon number
fluctuations change rapidly in the transition region of the QCD phase diagram.
Already at vanishing baryon chemical potential they deviate considerably from
the predictions of the hadron resonance gas model which reproduce the second to
fourth order moments of the net proton number fluctuations at RHIC. We point
out that the sixth order moments of baryon number and electric charge
fluctuations remain negative at the chiral transition temperature. Thus, they
offer the possibility to probe the proximity of the thermal freeze-out to the
crossover line.Comment: 24 pages, 12 EPS files, revised version, to appear in EPJ
Recent results and developments on double-gap RPCs for CMS
Abstract A 3 mm wide-gap Resistive Plate Chamber, as proposed for CMS, has been tested in the H2 Cern beam line. Results on efficiency, rate capability, time resolution and cluster size are reported
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