Recent results from the cosmic ray program of the NA61/SHINE experiment

NA61/SHINE is a fixed target experiment designed to study hadron-proton, hadron-nucleus and nucleus-nucleus interactions at the CERN Super-Proton-Synchrotron. In this paper we summarize the results from pion-carbon collisions recorded at beam momenta of 158 and 350 GeV/c. Hadron production measurements in this type of interactions is of fundamental importance for the understanding of the muon production in extensive air showers. In particular, production of (anti)baryons and $\rho^0$ are mechanisms responsible for increasing the number of muons which reaches the ground. The underestimation of the (anti)baryons or $\rho^0$ production rates in current hadronic interaction models could be one of the sources of the excess of muons observed by cosmic ray experiments. The results on the production spectra of $\pi^{\pm}$, K$^{\pm}$, p, $\bar{\text{p}}$, $\Lambda$, $\bar{\Lambda}$, K$^{0}_\text{S}$, $\rho^0$, $\omega$ and K$^{0*}$ are presented, as well as their comparison to predictions of hadronic interaction models currently used in air shower simulations.Comment: 8 pages, 9 figures. To appear in the proceedings of the 20th International Symposium on Very High Energy Cosmic Ray Interactions (ISVHECRI 2018), Nagoya, Japa

Measurements of Hadron Production in Pion-Carbon Interactions with NA61/SHINE at the CERN SPS

NA61/SHINE is a fixed target experiment designed to study hadron-proton, hadron-nucleus and nucleus-nucleus interactions at the CERN Super-Proton-Synchrotron. In this proceeding we present results on spectra of identified hadrons produced in pion-carbon production interactions, which are of fundamental importance to improve the extensive air shower modeling, and hence the interpretation of ultra-high-energy-cosmic-rays measurements. In particular, our measurements of (anti)baryons and $\rho^0$ production in pion-carbon interactions can contribute to improve the predictions of muon production by air shower simulations using hadronic interaction models. In this contribution we discuss the data analysis and the results from pion-carbon collisions recorded at beam momenta of 158 and 350 GeV/c. The preliminary spectra of $K^{\pm}$ and $p$($\bar{p}$) are shown, as well as a comparison to predictions of hadronic interaction models used in air shower simulations. Additionally, we present final results on the production of $\rho^0$, $\omega$ and $K^{0*}$ resonances.Comment: Proceedings of 35th International Cosmic Rays Conference, Busan, South Kore

Uso de redes sociales y factores del rendimiento académico en estudiantes de ingeniería electrónica de una Universidad del Callao 2020-II

La presente investigación tuvo como objetivo determinar la relación entre el uso de las redes sociales y factores del rendimiento académico en estudiantes de ingeniería electrónica de una Universidad del Callao 2020-II La investigación realizada responde al enfoque cuantitativo, de diseño no experimental, correlacional de corte transversal. Se utilizó un cuestionario para cada variable, cuyo un índice de fiabilidad fue de ,951 y ,892 para los instrumentos de la variable redes sociales y factores del rendimiento académico respectivamente, la muestra estuvo conformada por 90 estudiantes. Después del procesamiento de los datos y análisis de resultados obtenidos de la aplicación de los instrumentos se concluyó que: Existe una correlación negativa baja entre las variables redes sociales y factores del rendimiento académico con una significancia estadística p = 0,005 y un Rho de Spearman = -0.293, confirma una relación de tipo indirecta o inversa entre las variables de estudio

Novas ocorrências de sementes paleozoicas no Rio Grande do Sul e suas síndromes de dispersão

Sementes têm um importante papel para o entendimento das estratégias reprodutivas e afinidades botânicas das plantas. Porém, são poucos os estudos sobre esses órgãos para o Paleozoico. O Morro Papaléo, em Mariana Pimentel, no Rio Grande do Sul, é um importante sítio do Permiano Inferior com vasta fonte de sementes fósseis das mais variadas formas e tamanhos. O material deste estudo foi coletado no afloramento Cocuruto, que representa depósitos do Grupo Itararé, e as sementes deste material se encontram preservadas na forma de impressões/compressões. Analisou-se e descreveram-se sementes incluídas principalmente nos gêneros Samaropsis e Cordaicarpus, além de um exemplar relacionado ao gênero Cornucarpus. Como resultados foram identificadas as morfoespécies: Cordaicarpus brasilianus, Cordaicarpus cerronegrensis, Cordaicarpus truncata, Samaropsis kurtzii, Samaropsis seixasii e Samaropsis moreirana, além de algumas formas que não puderam ser classificadas em nível específico. Do ponto de vista das síndromes de dispersão, as sementes estudadas apresentaram pelo menos três tipos prováveis: a Barocoria, dispersão por gravidade Anemocoria, pelo vento, a Hidrocoria, pela água. Porém, uma possível dispersão auxiliada por animais não pode ser descartada. Elas incluem desde sementes de plantas pioneiras até aquelas de sucessão inicial, dadas as diferenças significativas nos tamanho das diferentes sementes. Quanto às afinidades botânicas, há sementes que podem ser vinculadas às glossopterídeas (grupo dominante), às Cordaitales e às coníferas, mas também às Gingkophyta. Por último, com base na associação estudada foi possível estabelecer uma correlação com estratos do topo do Grupo Itararé que afloram na região de Cerquilho, em São Paulo. Desta correlação, sugeriu-se Cordaicarpus cerronegrensis e Samaropsis kurtzii como espécies-guia úteis na Bioestratigrafia, sendo essa última típica de depósitos correlatos da Argentina, considerados do Permiano mais basal

Analysis of vectorcardiographic dynamic changes in patients with acute myocardial ischemia

This work evaluates the vectorcardiographic dynamic changes in ischemic patients before and during Percutaneous Transluminal Coronary Angioplasty (PTCA). Four vectorcardiographic parameters were computed in 51 ischemic and 52 healthy subjects with the objective of assessing the differences between both groups: ST Vector Magnitude Area (STVMa), T Vector Magnitude Area (TVMa), ST Vector Difference (STVD), and T Vector Difference (TVD). The conventional ST-Change Vector Magnitude (STCVM) and Spatial Ventricular Gradient (SVG) were also calculated. Results indicate that the most of them show significant differences between healthy and ischemic subjects. Since, the statistical minute-by-minute PTCA comparison against a healthy population shows that ischemic patients monitoring reached values of Sensitivity = 99.5% and Specificity = 99.4%, when STVD, TVD and SVG were used in the classification. In conclusion the sensitivity and specificity for acute ischemia monitoring could be increase with the used of only three vectorcardiographic parameters.Fil: Correa Prado, Raul Oscar. Universidad Nacional de San Juan. Facultad de Ingenieria. Departamento de Electronica y Automatica. Gabinete de Tecnologia Medica; ArgentinaFil: Arini, Pedro David. Universidad de Buenos Aires. Facultad de Ingenieria. Instituto de Ingeniería Biomédica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Saavedra 15. Instituto Argentino de Matemática; ArgentinaFil: Correa Prado, Lorena Sabrina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Saavedra 15. Instituto Argentino de Matemática; ArgentinaFil: Valentinuzzi, Maximo. Universidad de Buenos Aires. Facultad de Ingenieria. Instituto de Ingeniería Biomédica; ArgentinaFil: Laciar Leber, Eric. Universidad Nacional de San Juan. Facultad de Ingenieria. Departamento de Electronica y Automatica. Gabinete de Tecnologia Medica; Argentin

“Ars”: Visual Arts magazine by PPGAV, ECA/University of Sao Paulo

The “Ars” magazine, created by the graduate program in Visual Arts from Escola de Comunicação e Artes [School of Arts and Communication], at the University of Sao Paulo, gathers art relevant works by students at the university and outside of the academia. The magazine suggests that the issues involving an art school should not remain restricted to the academic environment, but should be taken as a cultural debate beyond the University walls and doubt art perspectives in a contemporary context

Multiscale characterization of the micromechanics of pure Mg

An important limitation of wrought (rolled and extruded) Mg alloys is their inherent strong mechanical anisotropy, a consequence of their hexagonal closed- packed (hcp) lattice. Several reasons contribute to this effect. First, at room temperature, the critical resolved shear stresses (CRSSs) of basal and non-basal slip systems have very different values, spanning several orders of magnitude; second, twinning, a very common deformation mechanism in these materials, exhibits a pronounced polarity, i.e. its activation is dependent on the relative orientation between the c-axis and the applied stress; finally, both hot and cold deformation processing textures are often quite sharp and the way the activation of different slip systems is influenced by the local texture and grain boundary network is not clear. Together, these factors lead to a dependence of the dominant deformation mechanisms on the texture, grain size, testing mode (tension or compression) and the testing direction, resulting in large differences in yield stress values and strain-hardening responses. In this work, we adopt a multiscale characterization strategy to unravel the micromechanisms of pure Mg. First, we present a coupled experimental and simulation study on the nanoindentation of pure Mg at different temperatures to determine the critical resolved shear stress evolution of the different slip systems at the single crystal level [1-3]. For this, several indentations were performed at temperatures between RT and 300 °C in individual grains of a polycrystalline sheet of pure Mg with different crystallographic orientations. The deformation profile and the microstructure around the indents was analyzed by atomic force microscopy (AFM) and electron backscatter diffraction (EBSD), to determine the CRSS of the different slip systems without grain boundary effects. EBSD assisted trace analysis during in-situ SEM mechanical testing of cold-rolled polycrystalline Mg sheets was then used to account for the role of the local microstructure, such as the local texture and grain boundary network, on the activation of the different deformation modes, In particular, it was found that, with decreasing grain size, at room temperature, a clear transition from non-basal to basal-slip dominated flow takes place under tension [4] and a transition from twinning to basal slip takes place under compression [5]. On the other hand, a similar transition from twinning to basal slip takes place with increasing temperature and decreasing strain rate [6]. The emergence of basal slip as a dominant mechanism is shown to be due to increasing levels of connectivity between favorably oriented grains, which facilitate slip transfer across grain boundaries. This study emphasizes the complexity of the micromechanics of pure Mg, where the activation of different deformation modes is strongly affected, not only by their single crystal CRSS levels, but also by the local grain boundary networks and local texture emerging from processing

Quaternion Neural Network with Temporal Feedback Calculation: Application to Cardiac Vector Velocity during Myocardial Infarction

Quaternion neural networks have been shownto be useful in image and signal processing applications.Herein, we propose a novel architecture of a neural unit model characterized by its ability of encoding 3-dimensional past information and that facilitates the learning of velocity patterns. We evaluate the implementation of the networkin a study of the cardiac vector velocity and its usefulness in early detection of patients with anterior myocardial infarction. Experimental results show an improvement of the performance in terms of convergence speed and precision when comparing with traditional methods. Furthermore, the network shows successful results in measuring the velocity reduction that is usually observed in vectorcardiogram signals in the presence of myocardial damage. Through a linear discriminant analysis, a pair of 100% / 98% of sensitivity/specificity is met with only two velocity parameters. We conclude that this method is a very promising developmentfor future computational tools devoted to early diagnosis ofheart diseases.Fil: Cruces, Pablo Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Saavedra 15. Instituto Argentino de Matemática Alberto Calderón; ArgentinaFil: Correa Prado, Raul Oscar. Universidad Nacional de San Juan. Facultad de Ingeniería. Departamento de Electrónica y Automática. Gabinete de Tecnología Médica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Laciar Leber, Eric. Universidad Nacional de San Juan. Facultad de Ingeniería. Departamento de Electrónica y Automática. Gabinete de Tecnología Médica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Arini, Pedro David. Universidad de Buenos Aires. Facultad de Ingeniería. Instituto de Ingeniería Biomédica; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Saavedra 15. Instituto Argentino de Matemática Alberto Calderón; ArgentinaXXI Congreso Argentino de BioingenieríaCórdobaArgentinaSociedad Argentina de BioingenieríaUniversidad Nacional de Córdob