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Clinical practice guidelines for dietary intake in hemodialysis focus on individual nutrients. Little is known about associations of dietary patterns with survival. We evaluated the associations of dietary patterns with cardiovascular and all-cause mortality among adults treated by hemodialysis.

We present preliminary results about photons production in relativistic heavy ion collisions. The main novelty of our study is the calculation of the contribution of the pre-equilibrium stage to the photon spectrum. The initial stage is modeled by an ensemble of classical gluon fields which decay to a quark-gluon plasma via the Schwinger mechanism, and the evolution of the system is studied by coupling classical field equations to relativistic kinetic theory; photons production is then computed by adding collision processes into the collision integral. We find that the contribution of early stage photons to the direct photon spectrum is substantial in the transverse momentum region pT≳1.5 GeV.

We review the application and successes of a phase-space coalescence plus fragmentation model that has been applied for hadronization at RHIC. The physical concept is discussed together with the practical implementation. The robustness of main predictions is reviewed together with several open issues like relevance of three dimensional calculation, finite width of the wave functions, effects of quark masses, energy-entropy conservation, space-momentum correlation. Eventually the relevance of coalescence also for the study of the microscopic interaction of heavy quarks is highlighted.

One of the primary aims of the ongoing nuclear collisions at Relativistic Heavy Ion Collider (RHIC) and Large Hadron Collider (LHC) energies is to create a Quark Gluon Plasma (QGP). The Heavy Quarks (HQ) constitutes a unique probe of the QGP properties. Both at RHIC and LHC energies a puzzling relation between the nuclear modification factor RAA(pT) and the elliptic flow v2(pT) related to heavy quark has been observed which challenged all the existing models.

The time evolution of cosmological parameters in the early Universe at the deconfinement transition is studied by an equation of state (EoS) which takes into account the finite baryon density and the background magnetic field. The nonperturbative dynamics is described by the field correlator method which gives, with a small number of free parameters, a good fit of lattice data. The entire system has two components, i.e., the quark-gluon plasma and the electroweak sector, and the solutions of the Friedmann equation show that the scale factors a(t) and H(t) = (1/a)da/dt are weakly dependent on the EoS, but the deceleration parameter q(t) and the jerk j(t) are strongly modified above the critical temperature Tc, corresponding to a critical time tc ≃ 20-25 μs. The time evolution of the cosmological parameters suggests that above and around Tc, there is a transient state of acceleration typical of a matter-dominated universe; this is entailed by the QCD strong interaction. The effect of the hadronic matter below Tc does not qualitatively change the previous behavior and one can consistently follow the cosmological evolution up to 100 μs. [ABSTRACT FROM AUTHOR]

Abstract:: In the reaction dynamics of intermediate-energy radioactive beams we can probe highly asymmetric nuclear matter in compressed as well as dilute phases. In this report some predictions are presented, based on analytical results as well as on reaction simulations. We suggest a series of experiments with RIB aimed to shed light on isospin properties of nuclear interactions in the medium.

Large Fabry–Pérot Interferometers (FPIs) are used in a variety of astronomical instrumentation, including spectro-polarimeters for 4 m class solar telescopes. In this work we comprehensively characterize the cavity of a prototype 150 mm FPI, sporting a novel, fully symmetric design. Of particular interest, we define a new method to properly assess the gravity effects on the interferometer’s cavity when the system is used in either the vertical or horizontal configuration, both typical of solar observations. We show that the symmetric design very effectively limits the combined effects of pre-load and gravity forces to only a few nm over a 120 mm diameter illuminated surface, with gravity contributing ∼2 nm peak-to-valley (∼0.3 nm rms) in either configuration. We confirm a variation of the tilt between the plates of the interferometer during the spectral scan, which can be mitigated with appropriate corrections to the spacing commands. Finally, we show that the dynamical response of the new system fully satisfies typical operational scenarios. We conclude that large, fully symmetric FPIs can be safely used within solar instrumentation in both, horizontal and vertical position, with the latter better suited to limiting the overall volume occupied by such an instrument.

The use of a programmable phase-shifting interferometer to detect the deformation of scattering surfaces is described. The interferometer is a commercial instrument in use for optical testing applications; the sample surface is imaged as a speckle pattern. The measuring procedure and the program are outlined, and an experimental demonstration on an aluminium plate under load is given.

Abstract: A suitable protocol for the transient expression of seed protein genes in protoplasts derived from cell suspension cultures of common bean has been established. Preliminary analyses of cultures to verify the synthesis of phaseolin – actively accumulated by the starting tissue, the developing cotyledon – showed that the protein was no longer synthesised after 5 days of culture. Transient expression of a phaseolin sequence, driven by a constitutive promoter, resulted in the accumulation of the correctly glycosylated and assembled protein. This system, when compared to tobacco protoplasts, largely avoids phaseolin fragmentation and the presence of contaminant polypeptides in the immunoprecipitates. Therefore, bean protoplasts are a good system to study the expression of wild-type as well as in-vitro-modified bean seed proteins.

Abstract: Sunflower suspension cell cultures were subjected to different heat treatments and the electrophoretic patterns of heat-induced endocellular and secreted proteins were analyzed. In response to heat shock (3 h at 40°C), sunflower cells synthesized new polypeptides and secreted them into the medium, while the synthesis of other polypeptides was suppressed. Two major polypeptides of about 50 and 32 kDa were strongly induced. The two-dimensional electrophoretic analysis showed that the 32-kDa band is composed of at least four different polypeptides. Western blotting hybridizations of secreted proteins with various lectins were performed. The 32-kDa band gave a positive signal with concanavalin A.

The intrinsic antiviral activity of macrophages has been studied in healthy donors and in patients affected by breast cancer and melanoma.In vitrodifferentiated macrophages from blood-derived monocytes were infected with measles virus, herpes simplex virus type 2 and adenovirus 17. The challenge was carried out with different multiplicities of infection and the synthesis of virus was tested by evaluating the single cycle growth curve in 24 h. The results obtained show that the restriction of virus infectivity by macrophages is strongly influenced by the multiplicity of infection. This was particularly evident with the adenovirus 17. Moreover, macrophages from patients with melanoma and breast cancer showed an impairment of the intrinsic antiviral activity in comparison with normal subjects.

Some sources of error with multiphase homodyne interferometry are reviewed. A major advantage over the classic two-channel approach is that the inaccuracies that originate from laser-power fluctuations and drifts are shown to be automatically compensated for by proper adjustment of the light beams.

A three-channel homodyne interferometer based on a structured delay plate is described. Detection and data acquisition are performed with standard optoelectronics in a PC environment. The device, which is used as a displacement sensor, features sub-nanometric sensitivity.

Proton-proton elastic scattering has been measured by the TOTEM experiment at the CERN Large Hadron Collider at √s = 7 TeV in special runs with the Roman Pot detectors placed as close to the outgoing beam as seven times the transverse beam size. The differential cross-section measurements are reported in the |t|-range of 0.36 to 2.5 GeV2. Extending the range of data to low t values from 0.02 to 0.33 GeV2, and utilizing the luminosity measurements of CMS, the total proton-proton cross section at √s = 7 TeV is measured to be (98.3 ±0.2stat ±2.8syst) mb.

We present several possibilities offered by the reaction dynamics of dissipative heavy ion collisions to study in detail the symmetry term of the nuclear equation of state EOS. In particular we focus the attention on transport properties and fragment production mechanisms. We discuss some new features of instabilities in asymmetric nuclear matter, underlying in particular the link between the nature of unstable fluctuations and the properties of the interaction. Now chemical instabilities may appear as isoscalar-like unstable oscillations, similarly to mechanical instabilities, leading to the formation of a more symmetric liquid phase, surrounded by a neutron rich gas phase, the Isospin Distillation effect. We present numerical simulations of multifragmentation processes in central heavy ion collisions at intermediate energies. In the same context, but in the case of semi-peripheral reactions, the dynamics of the so-called neck region is discussed. We show that in general the isospin dynamics plays an important role in all steps of the reaction, from prompt nucleon emission to primary cluster formation and eventually to sequential decays. Many observables appear rather sensitive to the isovector part of the nuclear EOS, in particular in more exclusive experiments.

In designing the optics of an imaging classic mount multi-étalon spectro-polarimeter as a post-focus instrument for the next generation of ground-based solar telescopes (Advanced Technology Solar Telescope, European Solar Telescope), many constraints must be considered. The large entrance pupil diameter of the telescope (4 m), the demanded large field of view (≥ 90 arcsec), high spectral resolving power (≥ 200000), and limited field-dependent blue-shift of the instrumental profile (≤ 3 FWHM) require Fabry-Pérot interferometers of large diameter (≥ 200 mm), lighted by highly collimated beams. This implies large optical elements and long optical paths. Moreover, to use interference pre-filters, placed between the interferometers to reduce the inter-reflections in axial-mount, with a relatively small diameter (≤ 70 mm), a "pupil adapter" should be included, with a further increase of the optical path length. Although a multi-étalon spectro-polarimeter works in quasi-monochromatic light, the Fraunhofer lines of interest cover a wide range of wavelengths (850 nm - 1650 nm), demanding a good chromatic aberration control. Finally, a low instrumental polarization (≤ 0.5 %) is required to allow a high polarimetric precision. In this paper a diffraction limited optical solution is described, fulfilling all the above requirements in a relative small volume.

We present numerical results of electric conductivity σel of a fluid obtained solving the relativistic transport Boltzmann equation in a box with periodic boundary conditions. We compute σel using two methods: the definition itself, i.e., applying an external electric field, and the evaluation of the Green-Kubo relation based on the time evolution of the current-current correlator. We find a very good agreement between the two methods. We also compare numerical results with analytic formulas in relaxation time approximation (RTA) where the relaxation time for σel is determined by the transport cross section σel, i.e., the differential cross section weighted with the collisional momentum transfer. We investigate the electric conductivity dependence on the microscopic details of the two-body scatterings: isotropic and anisotropic cross section as well as massless and massive particles. We find that the RTA underestimates considerably σell; for example, at screening masses mD ~ T, such underestimation can be as large as a factor of 2. Furthermore, we study a more realistic case for a quark-gluon system (QGP) considering both a quasiparticle model tuned to lattice QCD (1QCD) thermodynamics, as well as the case of a perturbative QCD (pQCD) gas with running coupling. Also, for these cases more directly related to the description of the QGP system, we find that the RTA significantly underestimates the σel by about 60%-80%. [ABSTRACT FROM AUTHOR]

We discuss the appearance of quark matter in neutron star cores, focusing on the possibility that the recent observation of a very heavy neutron star could constrain free parameters of quark matter models. For that, we use the equation of state derived with the field correlator method, extended to the zero temperature limit, whereas for the hadronic phase we use the equation of state obtained within both the nonrelativistic and the relativistic Brueckner-Hartree-Fock many-body theory. We find a strong dependence of the maximum mass both on the value of the qq interaction V1 and on the gluon condensate G2, for which we introduce a dependence on the baryon chemical potential mB. We find that the maximum masses are consistent with the observational limit for not too small values of V1. [ABSTRACT FROM AUTHOR]

A study of the shear viscosity of hadrons and quarks in hybrid stars has been performed in the framework of the microscopic transport theory. The neutron-star structure has been determined employing the equation of state from the Brueckner theory with three-body force for the hadron phase, and the equation of state from the MIT bag model for the deconfined quark phase. The nucleon-nucleon cross sections in dense matter have been consistently calculated from the Brueckner G matrix, whereas for the quark-quark cross sections the perturbative QCD has been adopted. Despite that the quark contribution to the shear viscosity is quite small at low temperature, the transition to the deconfined phase makes the equation of state much softer with the result that the baryon viscosity turns out to be enhanced instead of reduced in hybrid stars. The damping time scale of r-modes due to the shear viscosity has been evaluated for several stable configurations of a hybrid star and compared with the neutron-star spin-down time scale induced by the emission gravitation radiation from the r-modes. The enhancement of the total viscosity makes the viscosity time scale comparable with the gravitation radiation one at low temperature. [ABSTRACT FROM AUTHOR]

The two-equation of state model is used to describe the hadron-quark phase transition in dense-hot matter formed in heavy-ion collisions. The nonlinear Walecka model is used to describe the hadronic phase. For the quark phase, the Nambu-Jona-Lasinio (NJL) model coupled to Polyakov-loop fields is used to include both the chiral and (de)confinement dynamics. The phase diagrams are derived frorn the Gibbs conditions and compared with the results obtained in the hadron-NJL model without confinement. As in the hadron-NJL case a first order transition is observed, but with a critical end point at much higher temperatures, a consequence of the confinement mechanism that reduces the degrees of freedom of the quark matter in proximity to the phase transition. Particular attention is devoted to the phase transition in isospin asymmetric matter. Interesting isospin effects are found at high baryon density and reduced temperatures, which are in fact also common to other quark models, like the MIT bag model and the NJL model. Some possible observational signals are suggested to probe in heavy-ion collision experiments at intermediate energies. [ABSTRACT FROM AUTHOR]

We study the interpretation of lattice data about the thermodynamics of the deconfinement phase of SU(3) Yang-Mills theory, in terms of gluon quasiparticles propagating in a background of a Polyakov loop. A potential for the Polyakov loop, inspired by the strong coupling expansion of the QCD action, is introduced; the Polyakov loop is coupled to transverse gluon quasiparticles by means of a gaslike effective potential. This study is useful to identify the effective degrees of freedom propagating in the gluon medium above the critical temperature. A main general finding is that a dominant part of the phase transition dynamics is accounted for by the Polyakov loop dynamics; hence, the thermodynamics can be described without the need for diverging or exponentially increasing quasiparticle masses as T → Tc, at variance respect to standard quasiparticle models. [ABSTRACT FROM AUTHOR]

The two-equation-of-state model is used to describe the hadron-quark phase transition in asymmetric matter formed at high density in heavy-ion collisions. For the quark phase, the three-flavor Nambu-Jona-Lasinio effective theory is used to investigate the influence of dynamical quark mass effects on the phase transition. At variance to the MIT-Bag results, with fixed-current quark masses, the main important effect of the chiral dynamics is the appearance of an end point for the coexistence zone. We show that a first-order hadron-quark phase transition may take place in the region T⊂(50-80) MeV and ρB⊂(2-4)ρ0, which is possible to be probed in the new planned facilities, such as FAIR at GSI-Darmstadt and NICA at JINR-Dubna. From the isospin properties of the mixed phase, some possible signals are suggested. The importance of chiral symmetry and dynamical quark mass on the hadron-quark phase transition is stressed. The difficulty of an exact location of a critical end point comes from its appearance in a region of competition between chiral symmetry breaking and confinement, where our knowledge of effective QCD theories is still rather uncertain. [ABSTRACT FROM AUTHOR]

The TOTEM T2 telescope will measure inelastically produced charged particles in the forward region of the LHC Interaction Point 5. Each arm of the telescope consists in a set of 20 triple-GEM (Gas Electron Multiplier) detectors with tracking and trigger capabilities. The GEM technology has been considered for the design of TOTEM very forward T2 telescopes thanks to its characteristics: large active areas, good position and timing resolution, excellent rate capability and radiation hardness. Each of the four T2 half arms has been fully assembled and equipped with electronics at CERN and systematically tested in the SPS beam line H8 in 2008/09. After some optimization, the operation of the GEM chambers was fully satisfactory and the T2 telescopes were installed and commissioned in their final positions at the LHC interaction point. During the first LHC run (December 2009) the T2 telescopes have collected data, at 900 GeV and 2.36 TeV. We will present here the performances of the detector and the preliminary results obtained using the data collected. [ABSTRACT FROM AUTHOR]

We consider the SU(2) glasma with Gaussian fluctuations and study its evolution by means of classical Yang-Mills equations solved numerically on a lattice. Neglecting in this first study the longitudinal expansion, we follow the evolution of the pressures of the system and compute the effect of the fluctuations in the early stage up to t≈2 fm/c, that is the time range in which the glasma is relevant for high energy collisions. We measure the ratio of the longitudinal over the transverse pressure, PL/PT, and we find that unless the fluctuations carry a substantial amount of the energy density at the initial time, they do not change significantly the evolution of PL/PT in the early stage and that the system remains quite anisotropic. We also measure the longitudinal fields correlators both in the transverse plane and along the longitudinal direction: while at initial time fields appear to be anticorrelated in the transverse plane, this anticorrelation disappears in the very early stage, and the correlation length in the transverse plane increases. On the other hand, we find a dependence of the gauge invariant correlator on the longitudinal coordinate, which we interpret as a partial loss of correlation induced by the dynamics that we dub the gauge invariant string breaking. We finally study the effect of fluctuations on the longitudinal correlations: we find that string breaking is accelerated by the fluctuations and waiting for a sufficiently long time fluctuations lead to the complete breaking of the color strings. [ABSTRACT FROM AUTHOR]