Anti-strange meson-baryon interaction in hot and dense nuclear matter

We present a study of in-medium cross sections and (off-shell) transition rates for the most relevant binary reactions for strange pseudoscalar meson production close to threshold in heavy-ion collisions at FAIR energies. Our results rely on a chiral unitary approach in coupled channels which incorporates the $s$- and $p$-waves of the kaon-nucleon interaction. The formalism, which is modified in the hot and dense medium to account for Pauli blocking effects, mean-field binding on baryons, and pion and kaon self-energies, has been improved to implement full unitarization and self-consistency for both the $s$- and $p$-wave interactions at finite temperature and density. This gives access to in-medium amplitudes in several elastic and inelastic coupled channels with strangeness content $S=-1$. The obtained total cross sections mostly reflect the fate of the $\Lambda(1405)$ resonance, which melts in the nuclear environment, whereas the off-shell transition probabilities are also sensitive to the in-medium properties of the hyperons excited in the $p$-wave amplitudes [$\Lambda$, $\Sigma$ and $\Sigma^*(1385)$]. The single-particle potentials of these hyperons at finite momentum, density and temperature are also discussed in connection with the pertinent scattering amplitudes. Our results are the basis for future implementations in microscopic transport approaches accounting for off-shell dynamics of strangeness production in nucleus-nucleus collisions.Comment: 33 pages, 7 figures; enhanced discussion in Sec. 3; order of presentation of results modified in Sec. 4; updated reference list; corrected typos and wording; version to match publication in Phys. Rev.

Strange meson-baryon interaction in hot and dense medium: recent progress for a road to GSI/FAIR

We report recent results on the dynamics of strange hadrons in two-body reactions relevant for near-threshold production in heavy-ion collisions at GSI/FAIR and NICA-Dubna. In particular, $\bar K N$ scattering in hot and dense nuclear matter is studied within a chiral unitary framework in coupled channels, setting up the starting point for implementations in microscopic off-shell transport approaches. We focus on the calculation of transition rates with special attention to the excitation of hyperon resonances and isospin effects. Additionally, we explore "unconventional" strangeness generation by meson-meson and meson-baryon interactions in connection with recent HADES observations of deep sub-threshold $\phi$ and $\Xi$ production.Comment: 4 pages, 2 figures. To be published in the Proceedings of the 15th International Conference on Strangeness in Quark Matter (SQM2015), 6-11 July 2015, JINR, Dubna, Russi

Performance enhancement in the desing of amplifier and amplifier-less circuits in modern CMOS technologies.

In the context of nowadays CMOS technology downscaling and the increasing demand of high performance electronics by industry and consumers, analog design has become a major challenge. On the one hand, beyond others, amplifiers have traditionally been a key cell for many analog systems whose overall performance strongly depends on those of the amplifier. Consequently, still today, achieving high performance amplifiers is essential. On the other hand, due to the increasing difficulty in achieving high performance amplifiers in downscaled modern technologies, a different research line that replaces the amplifier by other more easily achievable cells appears: the so called amplifier-less techniques. This thesis explores and contributes to both philosophies. Specifically, a lowvoltage differential input pair is proposed, with which three multistage amplifiers in the state of art are designed, analysed and tested. Moreover, a structure for the implementation of differential switched capacitor circuits, specially suitable for comparator-based circuits, that features lower distortion and less noise than the classical differential structures is proposed, an, as a proof of concept, implemented in a ΔΣ modulator

Probing the hot and dense nuclear matter with K∗,Kˉ∗K^*,\bar{K}^* vector mesons

We investigate probing the hot and dense nuclear matter with strange vector mesons ($K^*, \bar{K}^*$). Our analysis is based on PHSD which incorporates partonic and hadronic dof and describes the full dynamics of HICs. This allows to study the $K^*$ and $\bar{K}^*$ meson formation from the QGP and the in-medium effects related to the modification of their properties during the propagation in dense and hot matter. We employ relativistic Breit-Wigner spectral functions for the $K^*,\bar{K}^*$ mesons with self-energies obtained from a G-matrix approach to study the role of in-medium effects on the $K^*$ and $\bar{K}^*$ meson dynamics in HIC from FAIR/NICA to LHC energies. According to our analysis most of the final $K^*/\bar{K}^*$s, that can be observed experimentally, are produced during the late hadronic phase and stem dominantly from the $K (\bar{K}) + \pi \to K^*(\bar{K}^*)$ formation channel. The amount of $K^*/\bar{K}^*$s originating from the QGP channel is comparatively small even at LHC energies and such $K^*/\bar{K}^*$s can hardly be reconstructed experimentally due to the rescattering of final pions and (anti-)kaons. This mirrors the results from our previous study on the strange vector-meson production in HICs at RHIC energies. The influence of the in-medium effects on the dynamics of the $K^*/\bar{K}^*$ is rather small since they are mostly produced at low baryon densities. Additional cuts on the shape of the observed signal and the range of the invariant mass region of the $K^*/\bar{K}^*$ also affect the final spectra. We demonstrate that the $K^*/\bar{K}^*$ in-medium effects are more visible at lower beam energy, e.g. FAIR/NICA and BES RHIC energies, where the production of $K^*/\bar{K}^*$s occurs at larger baryon densities. Finally, we present the experimental procedures to extract information on the in-medium masses and widths by fitting final mass spectra at LHC energies.Comment: 24 pages, 34 figures, extended version as published in Phys. Rev.

Intercampus : administració i docència compartides entre universitats catalanes a través d'Internet

Intercampus és un projecte de vuit universitats catalanes que té el suport del Departament d'Universitats, Recerca i Societat de la Informació de la Generalitat de Catalunya. Forma part del projecte Universitat digital de la Secretaria de Telecomunicacions i Societat de la Informació. A Intercampus, a través de la utilització de les tecnologies de la informació i la comunicació (TIC), es comparteixen de forma virtual processos universitaris que van des de l'administració (Administració Oberta) fins a la docència d'assignatures (Docència Compartida entre universitats)Intercampus is a project involving eight Catalan universities enjoying the backing of the Autonomous Government of Catalonia's Department of Universities, Research and the Information Society. It forms part of the Secretary for Telecommunications and Information Society's Digital University project. With Intercampus, via the use of information and communications technologies (ICT), shared online are university processes ranging from administration (Open Administration) to the teaching of subjects (Shared Teaching between universities

Leucemia/linfoma T del adulto HTLV1, un desafío para el clínico: Leukemia / Lymphoma T of the adult HTLV1, a challenge for the clinic

Adult T-cell leukemia/lymphoma (ATL) is an aggressive disease of mature activated T cell caused by human T-cell lymphotropic virus type 1 (HTLV-1). ATL carries a bad prognosis due to intrinsic chemoresistance and severe immunosuppression. The aggressive ATL forms, acute and lymphoma, are treated with chemotherapy associated with antiretroviral agents (AZT/IFN) the acute form. However, they have failed to achieve an impact on survival, that ranges from 8-10 months, respectively. Patients with chronic and smoldering ATL forms, have a better prognosis, but long term survival is poor as well, when these patients are managed with a watchfulwaiting policy or with chemotherapy. Apparently, AZT/IFN seams to benefit these patients. Meanwhile, prevention of dissemination of HTLV-1, is a must in public health policies, performing screening in blood banks and a screening to pregnant women to reduce/avoid vertical transmission of the virus.La leucemia / linfoma de células T en adultos (LLTA) es una enfermedad agresiva de células T maduras activadas causada por el virus linfotrópico de células T humano tipo 1 (HTLV-1). ATL tiene un mal pronóstico debido a la quimiorresistencia intrínseca y la inmunosupresión severa. Las formas agresivas de LLTA, aguda y linfoma, se tratan con quimioterapia asociada con agentes antirretrovirales (AZT / IFN). Sin embargo, no han logrado lograr un impacto en la supervivencia, que oscila entre 8 y 10 meses, respectivamente. Los pacientes con formas de LLTA crónicas y latentes tienen un mejor pronóstico, pero la supervivencia a largo plazo también es deficiente, tanto cuando estos pacientes se manejan con una política de espera vigilante o con quimioterapia. Aparentemente, las costuras AZT / IFN benefician a estos pacientes. Mientras tanto, la prevención de la diseminación del HTLV-1 es imprescindible en las políticas de salud pública, tanto por tamizaje del virus en bancos de sangre como a mujeres embarazadas para reducir / evitar la transmisión vertical del virus

La evaluación formativa de competencias a través de blogs. La experiencia de seis universidades catalanas

Como consecuencia del llamado proceso de Bolonia, los programas universitarios en la actualidad están, en su mayoría, diseñados por competencias. En este contexto, las prácticas de evaluación de los estudiantes deberían ser revisadas y adecuarse a lo que precisa el desarrollo de competencias de la educación superior. La experiencia que hemos llevado a cabo propone la utilización de una metodología y una herramienta concreta para asegurar un seguimiento suficiente y una retroalimentación adecuada de los estudiantes respecto a las competencias durante su proceso de aprendizaje