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Antecedentes. En Honduras, el teosinte (Dioon mejiae) se cultiva desde épocas prehistóricas y su uso como alimento de consumo humano ha sido aislado y reducido. Sin embargo, sus semillas son prometedoras por altos contenidos en carbohidratos, proteínas y minerales en el afrontamiento de la inseguridad alimentaria. Objetivos. Se propuso elaborar una harina de teosinte para almacenarla a dos temperaturas en los días 0, 30, 60 y 90 después de su preparación para determinar estabilidad. Asimismo, se preparó un extracto hidroalcohólico para determinar la capacidad antioxidante y toxicidad aguda oral. Métodos. Se midieron los valores de pH de las harinas almacenadas a diversas temperaturas y tiempos. Se utilizó la técnica de DPPH para la determinación de la capacidad antioxidante del extracto y ratas wistar para evaluar la toxicidad aguda oral. Resultados. La harina de teosinte no sufrió cambios físicos después de tres meses de almacenamiento y el valor promedio de pH obtenido fue de 6.80. El mayor porcentaje de inhibición fue del 94% para una concentración de 25.00 mg/mL del extracto y no se observaron efectos tóxicos agudos en los animales de experimentación. Conclusión. La harina de teosinte es un potencial alimento funcional, por su actividad antioxidante y su nula toxicidad aguda. Palabras clave: harina, capacidad antioxidante, toxicidad aguda oral, DPPH.

Se determinó la calidad ambiental del curso hídrico del río Guatapurí sobre el balneario Hurtado en los meses de diciembre de 2018 a junio de 2019, para ello, se utilizaron los índices QBR, IHF, BMWP/COL e índice de contaminación ICO evaluados en 3 tramos (aguas arriba – balneario – aguas abajo) en un trayecto de 1.387km durante las temporadas de lluvia y sequía. Los resultados obtenidos fueron correlacionados utilizando la metodología de Spearman. Los índices biológicos mostraron los siguientes resultados en el área de estudio; el BMWP/COL presentó calidad de agua muy limpias, en QBR presentó riberas con degradación extrema, IHF presentó hábitat acuático medianamente diverso y los parámetros físico químicos evaluados cumplieron parcialmente con la normatividad vigente para uso de agua. Los índices ICO evaluados mostraron relación entre fuerte y moderada con IHF, mientras que la relación con QBR fue moderada y BMWP/COL no fue aceptable. The environmental quality of the water course of the Guatapurí river on the Hurtado health resort was determined in the months of December 2018 to June 2019, for this, the QBR, IHF, BMWP / COL and ICO contamination index evaluated in 3 sections were used (upstream – health resort - downstream) on a 1.387km path during the rainy and dry seasons. The results obtained were correlated using Spearman's methodology. The biological indexes showed the following results in the study area; The BMWP / COL presented very clean water quality, in QBR it presented riverside with extreme degradation, IHF presented a moderately diverse aquatic habitat and the physical chemical parameters evaluated partially complied with current regulations for water use. The ICO indices evaluated showed a relationship between strong and moderate with IHF, while the relationship with QBR was moderate and BMWP / COL was not acceptable.

This work proposes a hybrid drive controlled configuration, using a minimum emissions search algorithm, which ensures the operation of the Internal Combustion Engine (ICE) in its fuel efficiency range, minimizing CO2 emissions by controlling the power flow direction of the Electric Machine (EM). This action is achieved by means of Power Converters, in this case a bi-directional DC-DC Buck-Boost Converter in the DC-side and a DC-AC T-type Converter as the inverting stage. Power flow is controlled by means of a bi-directional Model Predictive Control (MPC) scheme, based on an emissions optimization algorithm. A novel drivetrain configuration is presented where both, the ICE and the EM are in tandem arrangement. The EM is driven depending on the traction requirements and the emissions of the ICE. The EM is capable of operates in motor and generator mode ensuring the Minimum Emission Operating Point (MEOP) of the ICE regardless of the mechanical demand at the drivetrain. Simulation and validation results using a Hardware in the Loop (HIL) virtual prototype under different operation conditions are presented in order to validate the proposed overall optimization strategy.

Las Plataformas Itinerantes para la Acción Social–PIAS surgen en 2012 como una iniciativa de la Marina de Guerra del Perú para acercar servicios públicos a zonas alejadas en la Amazonía en embarcaciones que navegan por las cuencas amazónicas. Desde 2017, el Ministerio de Desarrollo e Inclusión Social–MIDIS creó el Programa de Acción para la inclusión Social–PAIS, que unificó los programas sociales Tambos y PIAS con la finalidad de mejorar y ampliar su cobertura en zonas rurales y poblaciones de pobreza y pobreza extrema, como son la Amazonía y las localidades altoandinas. A lo largo de los años, esta iniciativa se ha fortalecido y ha logrado articularse con diversas instituciones del sector público, debido —entre otros aciertos— al enfoque intercultural y la gestión de recursos humanos al interior del proyecto. Actualmente son cinco embarcaciones que trabajan inclusive en contextos difíciles como el de la pandemia, y acercan a la ciudadanía a servicios públicos de calidad.

Ebstein's anomaly is a rare complex congenital heart disease, first described in 1866 by physician Wilhelm Ebstein, characterized by anatomical and functional malformations of the tricuspid valve and the right ventricle because of inadequate delaminization of the tricuspid valve tissue. By presenting a clinical case and reviewing the literature, we analyzed the approach of an adult patient with Ebstein anomaly with ventricular preexcitation.We describe the case of a 34-year-old male patient, with a clinical history of palpitations and dyspnea, and his paraclinics documented Ebstein type B anomaly associated with patent foramen oval and paroxysmal supraventricular tachycardia, Successful radiofrequency ablation was performed and tricuspid valvuloplasty was proposed.It is concluded that Ebstein's anomaly is complex with clinical, morphological and physiopathological heterogeneous spectrum. Manifested from severe symptomatic forms in the neonatal period to asymptomatic or minimally symptomatic ones detected incidentally. Its diagnosis is based on clinical suspicion and confirmed by echocardiography or imaging studies. The therapeutic strategy may be based on medical management in its mild asymptomatic forms up to surgical interventions that include tricuspid valvuloplasty, palliative surgery, valve replacement or cardiac transplantation.la anomalía de Ebstein es una cardiopatía congénita compleja infrecuente, descrita por primera vez en 1866 por el médico Wilhelm Ebstein, caracterizada por malformaciones anatómicas y funcionales de la válvula tricúspide y del ventrículo derecho a consecuencia de una inadecuada deslaminización del tejido valvular tricuspídeo. Mediante la presentación de caso clínico y revisión de la literatura analizamos el abordaje de un paciente adulto con anomalía de Ebstein con preexcitación ventricular.describimos el caso de un paciente masculino de 34 años, con historial clínico de palpitaciones y disnea, en sus paraclínicos se documentó anomalía de Ebstein tipo B asociado a foramen oval permeable y taquicardia paroxística supraventricular, como tratamiento se realizó ablación por radiofrecuencia exitosa y proponiéndose valvuloplastia tricuspídea.la anomalía de Ebstein es compleja de espectro clínico, morfológico y fisiopatológico heterogéneo, manifestada desde formas graves sintomáticas en el periodo neonatal hasta asintomáticas o mininamente sintomáticas detectadas de forma incidental. Su diagnóstico parte de la sospecha clínica confirmándose a partir de ecocardiografía o estudios de imagen. La estrategia terapéutica puede estar basada en manejo médico en sus formas leves asintomáticas hasta intervenciones quirúrgicas que incluyen valvulo-plastia tricuspídea, cirugía paliativa, reemplazo valvular o trasplante cardiaco.

In this paper, a Model Predictive Control (MPC) strategy is introduced for its application in a four-level quasi-nested topology, feeding an Interior Permanent Magnet Synchronous Machine (IPMSM) AC-drive. The proposed control strategy is capable to synthesize the required output space vectors to ensure perfect tracking of the AC-drive speed reference under different loading conditions, while also ensuring voltage balance between the dc-link capacitors. The proposed converter topology is based on a reduced number of components compared to other mature converter topologies, such as the neutral-point clamped converter (NPC) or the active neutral-point clamped converter (ANPC) topologies, when compared in terms of the number of output voltage levels, since this quasi-nested topology does not require passive clamping devices such as diodes or active switches. Moreover, no floating dc-link capacitors with asymmetrical voltage levels are employed, thus simplifying the dc-link capacitor voltage balance mechanism. This work presents the switching operation principles and MPC control law when supplying an IPMSM AC-drive load are addressed in detail. Simulation and validation results using a Hardware in the Loop (HIL) prototype under different operation conditions are presented in order to validate the proposed converter topology and control strategy.

It is investigated the reconstruction during the slow-roll inflation in the most general class of scalar-torsion theories whose Lagrangian density is an arbitrary function $$f(T,\phi )$$ f ( T , ϕ ) of the torsion scalar T of teleparallel gravity and the inflaton $$\phi $$ ϕ . For the class of theories with Lagrangian density $$f(T,\phi )=-M_{pl}^{2} T/2 - G(T) F(\phi ) - V(\phi )$$ f ( T , ϕ ) = - M pl 2 T / 2 - G ( T ) F ( ϕ ) - V ( ϕ ) , with $$G(T)\sim T^{s+1}$$ G ( T ) ∼ T s + 1 and the power s as constant, we consider a reconstruction scheme for determining both the non-minimal coupling function $$F(\phi )$$ F ( ϕ ) and the scalar potential $$V(\phi )$$ V ( ϕ ) through the parametrization (or attractor) of the scalar spectral index $$n_{s}(N)$$ n s ( N ) and the tensor-to-scalar ratio r(N) as functions of the number of $$e-$$ e - folds N. As specific examples, we analyze the attractors $$n_{s}-1 \propto 1/N$$ n s - 1 ∝ 1 / N and $$r\propto 1/N$$ r ∝ 1 / N , as well as the case $$r\propto 1/N (N+\gamma )$$ r ∝ 1 / N ( N + γ ) with $$\gamma $$ γ a dimensionless constant. In this sense and depending on the attractors considered, we obtain different expressions for the function $$F(\phi )$$ F ( ϕ ) and the potential $$V(\phi )$$ V ( ϕ ) , as also the constraints on the parameters present in our model and its reconstruction.

It is investigated the reconstruction during the slow-roll inflation in the most general class of scalar-torsion theories whose Lagrangian density is an arbitrary function $f(T,\phi)$ of the torsion scalar $T$ of teleparallel gravity and the inflaton $\phi$. For the class of theories with Lagrangian density $f(T,\phi)=-M_{pl}^{2} T/2 - G(T) F(\phi) - V(\phi)$, with $G(T)\sim T^{s+1}$ and the power $s$ as constant, we consider a reconstruction scheme for determining both the non-minimal coupling function $F(\phi)$ and the scalar potential $V(\phi)$ through the parametrization (or attractor) of the scalar spectral index $n_{s}(N)$ and the tensor-to-scalar ratio $r(N)$ as functions of the number of $e-$folds $N$. As specific examples, we analyze the attractors $n_{s}-1 \propto 1/N$ and $r\propto 1/N$, as well as the case $r\propto 1/N (N+\gamma)$ with $\gamma$ a dimensionless constant. In this sense and depending on the attractors considered, we obtain different expressions for the function $F(\phi)$ and the potential $V(\phi)$, as also the constraints on the parameters present in our model and its reconstruction., Comment: 14 pages, 1 figure, Accepted version for publication in EPJC

The reconstruction of a k-essence inflationary universe, considering the unification between the swampland criteria and the attractor given by the scalar spectral index $n_S(N)$ together with the slow roll parameter $\epsilon(N)$in terms of the number of $e$-folds $N$ is studied. In the context of a coupling of the form $L(\phi)\,X$ in the k-essence model, we find the effective potential $V$ and the coupling parameter $L$ in terms of the scalar spectral index and the slow roll parameter under a general formalism. To apply the unification in our model, we consider some examples in order to rebuild the effective potential $V(\phi)$ and the coupling parameter $L(\phi)$ as a function of the inflaton field $\phi$. Here, we find that the reconstruction gives rise to an exponential potential and also to natural and hyperbolic inflation, respectively. Thus, in this article we show that it is possible to unify the theoretical foundations from the swampland criteria and the observational parameters corroborated by observations, in the reconstruction of an inflationary universe.