Correlations of Electrons from Heavy Flavor Decay with Hadrons in Au+Au and p+p Collisions

Measurements of electrons from the decay of open-heavy flavor mesons have shown that the yields are suppressed in Au+Au collisions compared to expectations from binary-scaled p+p collisions. These measurements indicate that charm and bottom quarks interact with the hot-dense matter produced in heavy-ion collisions much more than expected. Here we extend these studies to two-particle correlations where one particle is an electron from the decay of a heavy-flavor meson and the other is a charged hadron from either the decay of the heavy meson or from jet fragmentation. These measurements provide more detailed information about the interactions between heavy quarks and the matter, such as whether the modifcation of the away-side-jet shape seen in hadron-hadron correlations is present when the trigger particle is from heavy-meson decay and whether the overall level of away-side-jet suppression is consistent. We statistically subtract correlations of electrons arising from background sources from the inclusive electron-hadron correlations and obtain two-particle azimuthal correlations at $\sqrt{s_{NN}}$ =200 GeV between electrons from heavy-flavor decay with charged hadrons in p+p and also first results in Au+Au collisions. We find the away-side-jet shape and yield to be modified in Au+Au collisions compared to p+p collisions.Comment: talk given at Winter Workshop in Nuclear Dynamics 201

Nuevas pautas de migración y poblamiento: las dinámicas de los municipios de Cataluña

Cataluña exhibits important settlement changes. Population concentration has been replaced by a growing population dispersal, which main destination are municipalities above 10.000 inhabitants - usually classified as "intermedios"or "rurals"- At first, this population dispersal was concentrated in the Región Metropolitana de Barcelona, but during last years there is a growing population dispersal in more remote areas from Barcelonès. Nevertheless, it is not a common process in the whole Cataluña. These changes are basically produced by migration. Barcelones and the most populated cities which surroundit are the main origin. This paper analyses these processes that are transforming the Catalan area. It is needed a more detailed study about causes and economical and social effects this migration is producing. It is also pointed out some lines of research derived from other European examples, but they can help us as referente points to develop the analysis of these processes in Catalonia and Spain.Cataluña muestra cambios significativos en el sistema de poblamiento. La concentración de la población ha dado lugar a una dispersión creciente que tiene como principal destino los municipios de menos de 10.000 habitantes -habitualmente clasificados como intermedios o rurales-. Si bien en un primer momento dicha dispersión se concentraba en la Región Metropolitana de Barcelona, en los últimos años se asiste a una progresiva difusión de la población hacia áreas cada vez más alejadas del Barcelonés. Sin embargo, no es un proceso generalizado en todo el territorio catalán. Estos cambios son producto básicamente de la migración, actuando el Barcelonés y las principales ciudades de su entorno como origen. En esta comunicación se analizan estos procesos que suponen una transformación importante del sistema de poblamiento en el territorio. Un estudio más pormenorizado de los factores y de los impactos sociales y económicos que tiene esta migración está pendiente de realizarse. También se apuntan algunas líneas de reflexión que, a raíz de la literatura científica europea, pueden servir como elementos de guía para el análisis de estos procesos en el caso de Cataluña y España

Analysis by RNA-seq of transcriptomic changes elicited by heat shock in Leishmania major

Besides their medical relevance, Leishmania is an adequate model for studying post-transcriptional mechanisms of gene expression. In this microorganism, mRNA degradation/stabilization mechanisms together with translational control and post-translational modifications of proteins are the major drivers of gene expression. Leishmania parasites develop as promastigotes in sandflies and as amastigotes in mammalians, and during host transmission, the parasite experiences a sudden temperature increase. Here, changes in the transcriptome of Leishmania major promastigotes after a moderate heat shock were analysed by RNA-seq. Several of the up-regulated transcripts code for heat shock proteins, other for proteins previously reported to be amastigote-specific and many for hypothetical proteins. Many of the transcripts experiencing a decrease in their steady-state levels code for transporters, proteins involved in RNA metabolism or translational factors. In addition, putative long noncoding RNAs were identified among the differentially expressed transcripts. Finally, temperature-dependent changes in the selection of the spliced leader addition sites were inferred from the RNA-seq data, and particular cases were further validated by RT-PCR and Northern blotting. This study provides new insights into the post-transcriptional mechanisms by which Leishmania modulate gene expressionThis work was supported by grants (to B.A. and J.M.R.) from Ministerio de Economía, Industria y Competitividad, project number SAF2017-86965-R (co-funded with FEDER funds), and by the Network of Tropical Diseases Research RICET (RD16/0027/0008), co-funded with FEDER funds. The CBMSO receives institutional grants from the Fundación Ramón Areces and from the Fundación Banco de Santande

S-Wave Quarkonia in Potential Models

We discuss S-wave quarkonia correlators and spectral function using the Wong-potential, and show that these do not agree with the lattice results.Comment: based on talk presented at Strangeness in Quark Matter, UCLA, March 26-31, 200

Heavy-quark energy loss and thermalization in a strongly coupled SYM plasma

Using the AdS/CFT correspondence, we compute the radiative energy loss of a slowly decelerating heavy quark with mass M moving through a supersymmetric Yang Mills (SYM) plasma at temperature T at large t'Hooft coupling \lambda. The calculation is carried out in terms of perturbation in \sqrt{\lambda}T/M, and the rate of the energy loss is computed up to second order. We explain the physical meaning of each correction and estimate the thermalization time of a heavy quark moving in a strongly-coupled plasma.Comment: 14 pages, 1 figur

Transverse Momentum Broadening and the Jet Quenching Parameter, Redux

We use Soft Collinear Effective Theory (SCET) to analyze the transverse momentum broadening, or diffusion in transverse momentum space, of an energetic parton propagating through quark-gluon plasma. Since we neglect the radiation of gluons from the energetic parton, we can only discuss momentum broadening, not parton energy loss. The interaction responsible for momentum broadening in the absence of radiation is that between the energetic (collinear) parton and the Glauber modes of the gluon fields in the medium. We derive the effective Lagrangian for this interaction, and we show that the probability for picking up transverse momentum k_\perp is given by the Fourier transform of the expectation value of two transversely separated light-like path-ordered Wilson lines. This yields a field theoretical definition of the jet quenching parameter \hat q, and shows that this can be interpreted as a diffusion constant. We close by revisiting the calculation of \hat q for the strongly coupled plasma of N=4 SYM theory, showing that previous calculations need some modifications that make them more straightforward and do not change the result.Comment: 18 pages, 7 figures; v2, minor revisions, references added; v3, version to appear in Phys. Rev. D: Feynman rules corrected, improved explanations of the gauge invariance of our calculation and of how the scaling of SCET operators differs from that in other contexts in the literature; no changes to any result

Increase of gluthatione S-transferase, carboxyl esterase and carbonyl reductase in Fasciola hepatica recovered from triclabendazole treated sheep

Fasciolasis is a zoonotic parasitic disease caused by Fasciola hepatica and its control is mainly based on the use of triclabendazole (TCBZ). Parasite resistance to different anthelmintics is growing worldwide, including the resistance of F. hepatica to TCBZ. In the present work we evaluate “in vivo” the activity of xenobiotic metabolizing enzymes of phase I (carboxyl esterases) and phase II (glutathione S-transferases and carbonyl reductases) recovered of flukes from sheep treated with TCBZ. All three enzymes showed increased activity in TCBZ flukes returning 60 h post-treatment at similar to baseline unexposed flukes. TCBZ action may induce secondary oxidative stress, which may explain the observed increment in activities of the analyzed enzymes as a defensive mechanism. The enzymes analyzed are candidates to participate actively in the development of resistance at TCBZ in F. hepatica.Fil: Scarcella, Silvana Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tandil. Centro de Investigacion Veterinaria de Tandil; ArgentinaFil: Solana, M. V.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tandil. Centro de Investigacion Veterinaria de Tandil; ArgentinaFil: Fernandez, Vanesa. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tandil. Centro de Investigacion Veterinaria de Tandil; ArgentinaFil: Lamenza, Pamela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tandil. Centro de Investigacion Veterinaria de Tandil; ArgentinaFil: Ceballos, Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tandil. Centro de Investigacion Veterinaria de Tandil; ArgentinaFil: Solana, Hugo Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Tandil. Centro de Investigacion Veterinaria de Tandil; Argentina. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas; Argentin

Jet quenching and broadening: the transport coefficient q^\hat{q} in an anisotropic plasma

The jet quenching parameter $\hat{q}$ is analyzed for a quark jet propagating in an anisotropic plasma. The momentum anisotropy is calculated at high temperature of the underlying quark-gluon plasma. $\hat{q}$ is explicitly estimated in leading-logarithmic approximation by the broadening of the massless quark interacting via gluon exchange. A plasma instability is present. Strong indications are found that $\hat{q}$ is increasing with increasing anisotropy. Possible implications for the saturation scale $Q_s$ in $A-A$ collisions are pointed out.Comment: 1