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The purpose of this work is to be able to identify the levels of attention and meditation at the time the virtual classes are held, as a result of the COVID-19 pandemic; the conventional way of studying change considerably, and to a greater extent the physical place where the classes are held. Faced with this situation, children tend to be distracted by many distracting agents such as television. The proposed methodology allows evaluating the levels of attention and meditation in children when they are in their virtual classes, it is evaluated using a device for measuring brain signals better known as the brain-computer interface, which provides us with a level of attention and of meditation from 0 to 100%. The results that are presented are related to average values of the measurements made, to demonstrate the methodology was evaluated by two situations, the first is the measurement of a 6-year-old child and the second that of a 15-year-old, each of them With totally different situations in the realization of virtual classes, the measurements show that the 6-year-old child tends more to be distracted with values of 20% of attention and meditation when he is preparing for the class, achieving levels of attention of 72% When they are concentrated on the completion of the tasks, the results in the 15-year-old student show that they are less likely to be distracted, registering levels of attention of 30% when they are entering their classes and reaching high levels of attention above from 90% to 100% when they are solving math problems, the study concludes that students, depending on their age, pay different attention to virtual classes, recommending eliminating distraction agents to improve the attention of students when they are in virtual classes.

The ores of manganese are difficult to concentrate, nevertheless in this study of research, it has been achieved to raise the grade of manganese applying different equipments, machines, flow charts and diverse chemical reagents of flotation, obtaining the best results by means of flotation of the gangue, being the tail the concentrate of manganeso. The original ore has 23,8% Mn, on having it concentrate by inverse flotation, one manages to obtain 47,50% Mn in the concentrate, product very quoted on the intermal and external market., Los minerales de manganeso son difíciles de concentrar, no obstante, en este estudio de investigación se ha logrado elevar la ley del manganeso aplicando diferentes equipos, máquinas, diagramas de flujo y diversos reactivos químicos de flotación, obteniendo los mejores resultados mediante flotación de la ganga siendo el relave el concentrado de manganeso. El mineral original tiene 23,8% de Mn, al concentrarlo por flotación inversa se llega a obtener 47,50% Mn en el concentrado; producto muy cotizado en el mercado interno y externo.

Confocal Raman Microscopy combines the three-dimensional optical resolution of confocal microscopy and the sensitivity to molecular vibrations which characterizes Raman spectroscopy. Hence, the technique is capable of providing a three-dimensional image of the chemical composition with micrometer resolution. An image is obtained by raster-scanning the sample with respect to the laser focus and measuring the integrated intensity of characteristic Raman lines. We present three applications of this method to different classes of materials. In specimens of sintered ceramics, the composition is determined and the size and shape of grains are visualized. Spider silk fibers show Raman spectra which are characteristic of the spider species; in some cases the fibers have hollow cores. Polymer fibers produced by electrospinning from mixtures of polymer solutions feature homogeneous Raman spectra, even in cases of immiscible polymers. This demonstrates that the electrospinning technique produces materials which are largery homogeneous on the micrometer length scale. The compositions of the fibers agree for most samples, but not in all cases, with the compositions of the solutions.

Thermal and mechanical behavior of i-PP and NBR blends were studied, with special reference to the effect of dynamic vulcanization and compatibilization. DSC and TGA characterization techniques were employed. Tensile properties and impact strength were also evaluated. Results indicate that NBR content decreased PP’s crystallinity degree, increased thermal stability and slightly increased impact strength. Dynamic vulcanization did not show significant changes on mechanical or thermal properties. The addition of a compatibilizer seemed to lower interfacial tension of the dynamically vulcanized blend, although this decrease was not enough to increase tensile properties. Se estudió el comportamiento térmico y mecánico de mezclas de Polipropileno (i-PP) y caucho nitrilo (NBR), haciendo énfasis en el efecto de la vulcanización dinámica y la presencia de un compatibilizante. Se emplearon las técnicas de caracterización por DSC y TGA. Las propiedades de tensión y de resistencia al impacto también fueron evaluadas. Los resultados obtenidos indican que el contenido de NBR disminuye la cristalinidad del PP, incrementa la estabilidad térmica y aumenta ligeramente la resistencia al impacto. La vulcanización dinámica no arrojó cambios significativos en las propiedades mecánicas o térmicas. Finalmente, el uso de un agente compatibilizante pareciera disminuir la tensión interfacial de la mezcla vulcanizada dinámicamente, a pesar de que esta disminución no fue suficiente para mejorar las propiedades de tensión.

We report the final results of a prospective trial testing the combination of fludarabine, Ara-C and idarubicin (FLAI) followed by low-dose gemtuzumab ozogamicin (FLAI-GO) in 85 patients aged 60 years or more with CD33+ acute myeloid leukaemia (AML). Median age was 68 years (60-82); karyotype was unfavourable in 21 patients (24 %), intermediate in 63 (74 %) and favourable in 1 (2 %). There were five therapy-related deaths. Of the 80 evaluable patients, 47 achieved complete response (CR) (58 %); CR rates were 65 and 32 % in good-intermediate/poor karyotype patients, respectively. Median length of CR was 7 months (3-76). The cumulative incidence of relapse was 84 % with an actuarial survival of 50.3 % at 1 year and 14.4 % at 2 years. The study control population is an unselected consecutive historic cohort of 104 patients treated with the FLAI regimen, who were matched for age and prognostic factors. CR rates after FLAI-GO and FLAI were comparable. However, patients with de novo AML and intermediate-favourable karyotype receiving GO had a significantly lower risk of relapse at 2 years as compared to patients not receiving GO (n = 77) (40 vs 80 %, p = 0.01) and significantly better disease-free survival (p = 0.018) and overall survival (p = 0.022).