Density operator of a system pumped with polaritons: A Jaynes-Cummings like approach

We investigate the effects of considering two different incoherent pumpings over a microcavity-quantum dot system modelled using the Jaynes-Cummings Hamiltonian. When the system is incoherently pumped with polaritons it is able to sustain a large number of photons inside the cavity with Poisson-like statistics in the stationary limit, and also leads to a separable exciton-photon state. We also investigate the effects of both types of pumpings (Excitonic and Polaritonic) in the emission spectrum of the cavity. We show that the polaritonic pumping as considered here is unable to modify the dynamical regimes of the system as the excitonics pumping does. Finally, we obtain a closed form expression for the negativity of the density matrices that the quantum master equation considered here generates.Comment: 16 pages, 4 figure

Integral measurement of the 12C(n, p)12B reaction up to 10 GeV

The integral measurement of the 12C(n, p)12B reaction was performed at the neutron time-offlight facility n TOF at CERN. The total number of 12B nuclei produced per neutron pulse of the n TOF beam was determined using the activation technique in combination with a time-of-flight technique. The cross section is integrated over the n TOF neutron energy spectrum from reaction threshold at 13.6 MeV to 10 GeV. Having been measured up to 1 GeV on basis of the 235U(n, f) reaction, the neutron energy spectrum above 200 MeV has been re-evaluated due to the recent extension of the cross section reference for this particular reaction, which is otherwise considered a standard up to 200 MeV. The results from the dedicated GEANT4 simulations have been used to evaluate the neutron flux from 1 GeV up to 10 GeV. The experimental results related to the 12C(n, p)12B reaction are compared with the evaluated cross sections from major libraries and with the predictions of different GEANT4 models, which mostly underestimate the 12B production. On the contrary, a good reproduction of the integral cross section derived from measurements is obtained with TALYS-1.6 calculations, with optimized parameters.European Atomic Energy Communitys (Euratom) Seventh Framework Programme FP7/2007-2011-CHANDA (No. 605203)Narodowe Centrum Nauki (NCN)-UMO-2012/04/M/ST2/00700Croatian Science Foundation-No. 168

Biorefinery of biomass of agro-Industrial banana waste to obtain high-value biopolymers

On a worldwide scale, food demand is increasing as a consequence of global population growth. This makes companies push their food supply chains’ limits with a consequent increase in generation of large amounts of untreated waste that are considered of no value to them. Biorefinery technologies offer a suitable alternative for obtaining high-value products by using unconventional raw materials, such as agro-industrial waste. Currently, most biorefineries aim to take advantage of specific residues (by either chemical, biotechnological, or physical treatments) provided by agro-industry in order to develop high-value products for either in-house use or for sale purposes. This article reviews the currently explored possibilities to apply biorefinery-known processes to banana agro-industrial waste in order to generate high-value products out of this residual biomass source. Firstly, the Central and Latin American context regarding biomass and banana residues is presented, followed by advantages of using banana residues as raw materials for the production of distinct biofuels, nanocellulose fibers, different bioplastics, and other high-value products Lastly, additional uses of banana biomass residues are presented, including energy generation and water treatmen

Mejoramiento del desempeño docente de profesores graduados de carreras de la salud. Presente y futuro

La superación del profesional graduado de carreras no pedagógicas resulta una necesidad de la educación permanente, por cuanto el profesional graduado de ingeniera, medicina u otra carrera que ocupa una plaza como docente en un centro universitario debe formar las competencias necesarias para un desempeño docente de calidad. En esta dirección, las universidades cubanas ejecutan acciones de superación, específicamente cursos de postgrado organizados en diplomados y maestrías, que constituyen una de las principales vías para ese mejoramiento del desempeño docente de ese profesional. Es así que el objetivo de este trabajo fue analizar las acciones de superación pedagógica que desarrolla la Facultad de Ciencias Médicas Miguel Enríquez de la Universidad Médica de La Habana, Cuba para el mejoramiento del desempeño docente de los profesores graduados de carreras no pedagógicas. Se usó la metodología cualitativa mediante el análisis de las opiniones recogidas al terminar cada curso. Se evaluaron la aplicabilidad, asequibilidad y tiempo necesario de aprendizaje a través de una escala de cinco puntos. Se analizaron los doce cursos desarrollados en la Facultad de Ciencias Médicas Miguel Enríquez durante los años 2000-2020 dirigidos al mejoramiento del desempeño docente. La aplicabilidad, asequibilidad y tiempo de aprendizaje fueron los criterios evaluados, como resultado se requiere la reelaboración e los mismos; así como el diseño de otros para el futuro inmediato. A partir del análisis unos cursos son mantenidos y otros añadidos en la estrategia de superación de la facultad.Palabras clave: Desempeño docente, postgrado, profesor graduado de carreras no pedagógicas. AbstractThe overcoming of the professional graduated from non-pedagogical careers is a need of permanent education, since the professional graduated from engineering, medicine or another career who occupies a position as a teacher in a university center, must form the necessary competencies for a teaching performance of quality. In this direction, Cuban universities carry out improvement actions, specifically postgraduate courses organized in diploma and master's degrees, which constitute one of the main ways to improve the teaching performance of this professional. Thus, the objective of this work was to analyze the pedagogical improvement actions carried out by the Miguel Enríquez Faculty of Medical Sciences of the Medical University of Havana, Cuba, for the improvement of the teaching performance of professors graduated from non-pedagogical careers. The qualitative methodology was used by analyzing the opinions collected at the end of each course. The applicability, affordability, and time required for learning were assessed using a five-point scale. The twelve courses developed in the Miguel Enríquez Faculty of Medical Sciences during the years 2000-2020 were analyzed, aimed at improving teaching performance. The applicability, affordability and learning time were the evaluated criteria, as a result, reworking of them is required; as well as the design of others for the immediate future. Based on the analysis, some courses are maintained and others are added to the faculty's overcoming strategy.Keywords: Teaching performance, postgraduate, graduate professor of non-pedagogical careers

Measurements of neutron cross sections for advanced nuclear energy systems at n_TOF (CERN)

INPC 2013 – International Nuclear Physics ConferenceThe n_TOF facility operates at CERN with the aim of addressing the request of high accuracy nuclear data for advanced nuclear energy systems as well as for nuclear astrophysics. Thanks to the features of the neutron beam, important results have been obtained on neutron induced fission and capture cross sections of U, Pu and minor actinides. Recently the construction of another beam line has started; the new line will be complementary to the first one, allowing to further extend the experimental program foreseen for next measurement campaign

Measurement of the 70Ge(n,γ) cross section up to 300 keV at the CERN n_TOF facility

Neutron capture data on intermediate mass nuclei are of key importance to nucleosynthesis in the weak component of the slow neutron capture processes, which occurs in massive stars. The (n,γ) cross section on 70Ge, which is mainly produced in the s process, was measured at the neutron time-of-flight facility n_TOF at CERN. Resonance capture kernels were determined up to 40 keV neutron energy and average cross sections up to 300 keV. Stellar cross sections were calculated from kT =5 keV tokT =100 keV and are in very good agreement with a previous measurement by Walter and Beer (1985) and recent evaluations. Average cross sectionsareinagreementwithWalterandBeer(1985)overmostoftheneutronenergyrangecovered,whilethey aresystematicallysmallerforneutronenergiesabove150keV.Wehavecalculatedisotopicabundancesproduced in s-process environments in a 25 solar mass star for two initial metallicities (below solar and close to solar). While the low metallicity model reproduces best the solar system germanium isotopic abundances, the close to solar model shows a good global match to solar system abundances in the range of mass numbers A=60–80.Austrian Science Fund J3503Adolf Messer Foundation ST/M006085/1European Research Council ERC2015-StGCroatian Science Foundation IP-2018-01-857

Strong coupling of two interacting excitons confined in a nanocavity-quantum-dot system

We present a study of the strong coupling between radiation and matter, considering a system of two quantum dots, which are in mutual interaction and interacting with a single mode of light confined in a semiconductor nanocavity. We take into account dissipative mechanisms such as the escape of the cavity photons, decay of the quantum dot excitons by spontaneous emission, and independent exciton pumping. It is shown that the mutual interaction between the dots can be measured off-resonance, only if the strong coupling condition is reached. Using the quantum regression theorem, a reasonable definition of the dynamical coupling regimes is introduced in terms of the complex Rabi frequency. Finally, the emission spectrum for relevant conditions is presented and compared with the above definition, demonstrating that the interaction between the excitons does not affect the Strong Coupling

Evaluación de la variabilidad genética de clones de caucho natural presentes en la colección clonal del instituto Sinchi, mediante el uso de descriptores morfológicos

Genetic diversity of natural rubber clones of the in SINCHI Institute’s clone collection was assessed. Clones of Hevea brasiliensis (Willd. ex Adr. De Juss.) Muell.Arg., Hevea spp. (H. brasiliensis x H. benthamiana), and three more species of Hevea genus are a part of the collection. Seventy-two materials were characterized with twenty-eight morphological descriptors. They were later used to generate a similarity matrix through the analysis of multi-categorical variables, and to obtain clusters based on the matrix. A low variability between clones of H. brasiliensis and H. spp. was observed, presumably because of the direct descendants of most of the materials from crosses of parental PB 80, PB 5/51, PB 49 and Tjir, exception made of clone GU 1410. Clustering between some materials product of exclusive cross of PB series, a group between clones descendants of parental clones PB 86, and clustering between descendants of parental clones PB 5/51, were observed. Clones from other species of Hevea differ from this big group.Se estimó la variabilidad genética de clones de caucho natural presentes en la colección clonal del Instituto SINCHI, los cuales incluyen clones de Hevea brasiliensis (Willd. ex Adr. De Juss.) Muell.Arg., Hevea spp. (H. brasiliensis x H. benthamiana) y tres especies más del género Hevea. Se realizó la caracterización de 72 materiales con veintiocho descriptores morfológicos, los cuales posteriormente fueron utilizados para generar una matriz de similaridad por medio de un análisis de variables multicategóricas, así como la obtención de agrupamientos con base en esta. Con excepción del clon GU 1410, se observó una baja variabilidad entres los clones de H. brasiliensis y Hevea spp., presumiblemente por la descendencia directa de la mayoría de materiales entre cruces de los parentales PB 80, PB 5/51, PB 49 y Tjir, que evidenciaron agrupamientos entre algunos materiales producto de cruces exclusivos de la series PB, entre clones descendientes del parental PB 86 y entre clones descendientes del parental PB 5/51. Los clones de otras especies del género Hevea divergen de este gran grupo