Investigating the inclusive transverse spectra in high-energy pppp collisions in the context of geometric scaling framework

The presence of geometric scaling within the $p_T$ spectra of produced hadrons at high energy $pp$ collisions using small-$x$ $k_T$-factorization is investigated. It is proposed a phenomenological parameterization for the unintegrated gluon distribution in the scaling range which reproduces the features of the differential cross section both in the saturated and dilute perturbative QCD regimes. As the saturation scale acts as an effective regulator of the infrared region (IR), the extension of the model to quantities usually associated to soft physics is studied. The approach is applied to compute the average $p_T$ and the rapidity distribution of produced gluons at high energies.Comment: 11 pages, 9 figure

Coulomb corrections to inclusive cross sections at the future Electron - Ion Collider

The experimental results of the future electron -- ion ($e A$) collider are expected to constrain the dynamics of the strong interactions at small values of the Bjorken -- $x$ variable and large nuclei. Recently it has been suggested that Coulomb corrections can be important in inclusive and diffractive $eA$ interactions. In this paper we present a detailed investigation of the impact of the Coulomb corrections to some of the observables that will be measured in the future $eA$ collider. In particular, we estimate the magnitude of these corrections for the charm and longitudinal cross sections in inclusive and diffractive interactions. Our results demonstrate that the Coulomb corrections for these observables are negligible, which implies that they can be used to probe the QCD dynamics.Comment: 9 pages, 6 figures. Improved version to be published in Physical Review

Nuclear Modification Factor in Small System Collisions within Perturbative QCD Including Thermal Effects

In this paper, dedicated to the memory of the late Prof. Jean Cleymans, the nuclear modification factors, $R_{xA}$, are investigated for pion production in small system collisions, measured by PHENIX experiment at RHIC (Relativistic Heavy Ion Collider). The theoretical framework is the transverse momentum $k_T$-factorization formalism for hard processes at small momentum fraction, $x$. Evidence for collective expansion and thermal effects for pions, produced at equilibrium, is studied based on phenomenological parametrization of blast-wave type in the relaxation time approximation. The dependencies on the centrality and on the projectile species are discussed in terms of the behavior of Cronin peak and the suppression of $R_{xA}$ at large transverse momentum, $p_T$. The multiplicity of produced particles, which is sensitive to the soft sector of the spectra, is also included in the present analysis.Comment: 12 pages, 4 figures. Contribution to MDPI Physics Special Issue "Jean Cleymans: A Life for Physics", dedicated to the memory of Professor Jean Cleyman

Investigating entanglement entropy at small-x in DIS off protons and nuclei

In this work we analyse the entanglement entropy in deep inelastic scattering off protons and nuclei. It is computed based on the formalism where the partonic state at small-x is maximally entangled with proton being constituted by large number of microstates occuring with equal probabilities. We consider analytical expressions for the number of gluons, N_{gluon}, obtained from gluon saturation models for the dipole-target amplitudes within the QCD color dipole picture. In particular, the nuclear entanglement entropy per nucleon is studied. We also study the underlying uncertainties on these calculations and compare the results to similar investigations in literature.Comment: 11 pages, 5 figures and 1 table (revised, conclusions unchanged). Extended version to be published in Physical Review

Satisfaction regarding the methods used to evaluate hotel performance

This study has four specific objectives: to analyse the association between hotel features and the methods used to evaluate hotel performance; to analyse the convergence between what the theory considers as appropriate performance evaluation methods, and the opinion of the hotels’ financial managers; to identify the factors that explain why the same method is considered appropriate in some hotels and not in others; to analyse whether there is an association between the method used to evaluate hotel performance and customer satisfaction. Data collection was made using two sequential methods. Firstly, we conducted a survey directed at the financial managers of 3, 4 and 5-star hotels located in Portugal, where we obtained 189 completed surveys. Secondly, we collected information regarding the degree of customer satisfaction for the hotels responding to the initial survey using the information available on the online platform Tripadvisor.com. The results obtained allow us to indicate as main contributions the following: validation of the expectations confirmation paradigm as an adequate theoretical model to explain customer satisfaction in hotels, namely showing that the performance evaluation methods can be regarded as factors affecting the actual customer experience; to demonstrate that the satisfaction indicator room is what contributes the most to the level of overall customer satisfaction; to demonstrate the existing convergence between what the theory considers as appropriate performance evaluation methods, and the opinion of the hotels’ financial managers, unlike what was previously reported in other industries.info:eu-repo/semantics/publishedVersio

Exclusive vector meson production in electron-ion collisions

We calculate the nuclear cross section for coherent and incoherent vector meson production within the QCD color dipole picture, including saturation effects. Theoretical estimates for scattering on both light and heavy nuclei are given over a wide range of energy.Comment: 11 pages, 6 figures, 1 tabl

Effect of clay mineral addition on properties of bio-based polymer blends

The effect of clay mineral addition to bio-based blends on morphology and physical properties of thermoplastic starch (TPS) and polypropylene grafted with maleic anhydride (PP-g-MA) was investigated. Blends and nanocomposites containing organoclay, Cloisite 30B, were prepared by melt mixing and characterized by several techniques. X-ray diffraction (XRD), scanning and transmission electron microscopy (SEM, STEM) and dynamic mechanical analysis (DMA) demonstrate a very good dispersion of the clay mineral in the polymer matrix, an increase of polymer compatibility and an improvement of mechanical properties. Biodegradation studies performed in compost revealed that Cloisite 30B addition enhanced the matrix biodegradability. Therefore clay minerals, which can be obtained from natural resources, can be efficiently used to improve the properties of bio-based materials and contribute to sustainability.The authors acknowledge the n-STeP - Nanostructured systems for Tail, with reference NORTE-07-0124-FEDER-000039, supported by the Programa Operacional Regional do Norte (ON.2), PEst-C/CTM/LA0025/2013 (Strategic Project - LA 25 - 2013-2014)

Cast nephropathy: an extremely rare renal presentation of Waldenström's macroglobulinaemia

Renal involvement in Waldenström's macroglobulinaemia (WM) is very unusual when compared to multiple myeloma. We report a case of a patient who developed anuric acute kidney injury secondary to cast nephropathy, dependent on high-flux haemodialysis. Complementary study revealed the presence of blood IgM monoclonal gammopathy and a massive bone marrow lymphoplasmacytic infiltration. There were no osteolytic lesions and no clinical signs/symptoms of hyperviscosity syndrome. The diagnosis of WM was established and a dexamethasone plus cyclophosphamide regime was started, in addition to plasmapheresis. The patient partially recovered renal function allowing haemodialysis and plasmapheresis withdrawal. He remained asymptomatic with a good response to chemotherapy and 12 months after his renal function remained stable. This is a rare clinical case in which WM presented as an IgM cast nephropathy, which in turn is an extremely rare renal presentation of this equally rare haematological disorder