461 research outputs found
Isotope Labelling for Reaction Mechanism Analysis in DBD Plasma Processes
Dielectric barrier discharge (DBD) plasmas and plasma catalysis are becoming an alternative procedure to activate various gas phase reactions. A low-temperature and normal operating pressure are the main advantages of these processes, but a limited energy efficiency and little selectivity control hinder their practical implementation. In this work, we propose the use of isotope labelling to retrieve information about the intermediate reactions that may intervene during the DBD processes contributing to a decrease in their energy efficiency. The results are shown for the wet reforming reaction of methane, using D2O instead of H2O as reactant, and for the ammonia synthesis, using NH3/D2/N2 mixtures. In the two cases, it was found that a significant amount of outlet gas molecules, either reactants or products, have deuterium in their structure (e.g., HD for hydrogen, CDxHy for methane, or NDxHy for ammonia). From the analysis of the evolution of the labelled molecules as a function of power, useful information has been obtained about the exchange events of H by D atoms (or vice versa) between the plasma intermediate species. An evaluation of the number of these events revealed a significant progression with the plasma power, a tendency that is recognized to be detrimental for the energy efficiency of reactant to product transformation. The labelling technique is proposed as a useful approach for the analysis of plasma reaction mechanisms
Portal Web Educativo Homo Pensantes: Herramienta Didáctica Para Promover La Competencia Argumentativa Y Fomentar El Pensamiento Crítico
El presente trabajo de investigación propone el desarrollo de una herramienta digital a manera de portal web 2.0 llamado Portal Homo pensantes, como estrategia y metodología para las clases de español de noveno grado del colegio República de Colombia, con el objetivo de que se desarrolle en los estudiantes la capacidad argumentativa y el pensamiento crítico. Para esto, se hizo una investigación eminentemente cualitativa aunque emplea la encuesta como una de las herramientas de recolección de información. Finalmente, se realizó un análisis de la experiencia de los docentes y sus estudiantes en las clases, así como de la observación y las entrevistas realizadas a la población con el fin de establecer deductivamente ciertas generalidades de la educación colombiana y sus ventajas en relación con las herramientas digitales
Study of humoral and cellular immunity in vaccinated with mRNA-1273
This work was supported by "Investigacion y Desarrollo (I + D) del Sistema Andaluz de Salud (SAS)" and Instituto de Salud Carlos III (Proyecto FIS PI21/01708).The new vaccines against SARS-CoV-2 have raised a lot of expectations about their ability to induce immunity and the
duration of this. This is the case of mRNA vaccines such as Moderna’s mRNA-1273. Therefore, it is necessary to study
the humoral and cellular immunity generated by these vaccines. Our objectives are determining what is the normal
response of antibody production, and what is the level of protective antibodies and monitoring patients in case of subsequent
infection with COVID-19. We present the first results of a longitudinal study of the humoral response in 601
health workers vaccinated with Moderna. The results show a humoral immunity at 90 days after the second dose of
100%, with a strong decrease between the levels of circulating anti-S IgG antibodies between days 30 and 90 postvaccination.
Observing a steeper decline in those who had higher titles at the beginning. In addition, we present a cellular
response of 86% at three months after the second dose, which is related to low humoral response.Investigacion y Desarrollo (I + D) del Sistema Andaluz de Salud (SAS)Instituto de Salud Carlos III
European Commission FIS PI21/0170
Surface chemistry and germination improvement of Quinoa seeds subjected to plasma activation
Plasma treatment is recognized as a suitable technology to improve germination efficiency of numerous seeds. In this work Quinoa seeds have been subjected to air plasma treatments both at atmospheric and low pressure and improvements found in germination rate and percentage of success. Seed water uptake by exposure to water vapor, although slightly greater for plasma treated seeds, did not justify the observed germination improvement. To identify other possible factors contributing to germination, the chemical changes experienced by outer parts of the seed upon plasma exposure have been investigated by X-ray photoemission spectroscopy (XPS) and scanning electron microscopy (SEM-EDX). XPS revealed that the outer layers of the Quinoa plasma treated seeds were highly oxidized and appeared enriched in potassium ions and adsorbed nitrate species. Simultaneously, SEM-EDX showed that the enrichment in potassium and other mineral elements extended to the seed pericarp and closer zones. The disappearance from the surface of both potassium ions and nitrate species upon exposure of the plasma treated seeds to water vapor is proposed as a factor favoring germination. The use of XPS to study chemical changes at seed surfaces induced by plasma treatments is deemed very important to unravel the mechanisms contributing to germination improvement
Nazismo
12 p.El nazismo es una ideología totalitarista con auge en Alemania, impuesta por el partido nacional socialista obrero “NAZI”. En el siguiente trabajo se expondrán los principios y herramientas con los que este régimen hacía uso de su poder, determinando si esta ideología buscaba un bien común o por el contrario su fin era el individual; además de señalar si Hitler como mayor representante de esta ideología fue prudente o no en el momento de ejecutar sus actos como canciller y presidente a su vez, pero no solo observaremos la prudencia jurídica de este exponente, también se enfatizará en la ideología impartida en el tiempo de la historia de la segunda guerra mundial y de la que actualmente se siguen viendo movimientos a favor, evidentemente no con el mismo ímpetu, ni alcanzando la escala mundial vista anteriormente, pero sí que ha generado gran desconcierto entre la multitud.Introducción
Nazismo
Conclusiones
Referencia
Acute oxidant damage promoted on cancer cells by amitriptyline in comparison with some common chemotherapeutic drugs
Oxidative therapy is a relatively new anticancer strategy
based on the induction of high levels of oxidative stress,
achieved by increasing intracellular reactive oxygen
species (ROS) and/or by depleting the protective
antioxidant machinery of tumor cells. We focused our
investigations on the antitumoral potential of amitriptyline
in three human tumor cell lines: H460 (lung cancer), HeLa
(cervical cancer), and HepG2 (hepatoma); comparing the
cytotoxic effect of amitriptyline with three commonly used
chemotherapeutic drugs: camptothecin, doxorubicin, and
methotrexate. We evaluated apoptosis, ROS production,
mitochondrial mass and activity, and antioxidant defenses
of tumor cells. Our results show that amitriptyline produces
the highest cellular damage, inducing high levels of ROS
followed by irreversible serious mitochondrial damage.
Interestingly, an unexpected decrease in antioxidant
machinery was observed only for amitriptyline. In
conclusion, based on the capacity of generating ROS
and inhibiting antioxidants in tumor cells, amitriptyline
emerges as a promising new drug to be tested for
anticancer therapy
Acoustic radiation force impulse elastography and contrast-enhanced sonography of sinusoidal obstructive syndrome (veno-occlusive disease): Preliminary results
We report quantitative liver acoustic radiation force impulse (ARFI) elastographic findings
in 2 cases of sinusoidal obstructive syndrome and liver contrast-enhanced sonographic
features in one of these cases. To our knowledge, findings in this condition from
these techniques have not been reported previously. Acoustic radiation force impulse
elastography showed median high shear wave velocities (case 1, 2.75 m/s; case 2, 2.58
m/s) that normalized after specific treatment for sinusoidal obstructive syndrome;
therefore, ARFI elastography provided quantitative information that helped diagnose
this condition as well as monitor the response to treatment. Contrast-enhanced sonographic
findings in one of the cases showed patchy liver enhancement that correlated
with the high-velocity patchy distribution on ARFI elastography in that case and enhanced
multidetector row computed tomographic findings in the other case. This contrast-
enhanced sonographic pattern progressively normalized during follow-up after
specific treatment. The elastographic features in both cases and contrast-enhanced
sonographic features in one of them contributed to early diagnosis and follow-up of sinusoidal
obstructive syndrome in both patients. Further prospective studies are necessary
to define the role of ARFI elastography and contrast-enhanced sonography in the
early diagnosis and clinical follow-up of this conditio
Derecho a la vida
12 p.En el siguiente trabajo se presentará el significado e importancia de este derecho entendiendo el por qué es imprescindible para la razón de ser de los demás derechos de la persona, observaremos como Colombia y algunas organizaciones actúan a favor de la protección de este derecho, identificando asimismo las consecuencias que atañen infringirlo También se inmiscuirá un poco en los numerosos debates que se han dado por saber si en ciertas acciones como el aborto, biogenética, la pena de muerte se ve vulnerado el derecho a la vida o no y analizaremos como estas situaciones que se presentan actualmente atentan contra este patrimonio universal
Resistive Switching and Charge Transport in Laser-Fabricated Graphene Oxide Memristors: A Time Series and Quantum Point Contact Modeling Approach
This work investigates the sources of resistive switching (RS) in recently reported
laser-fabricated graphene oxide memristors by means of two numerical analysis tools linked to
the Time Series Statistical Analysis and the use of the Quantum Point Contact Conduction model.
The application of both numerical procedures points to the existence of a filament connecting the
electrodes that may be interrupted at a precise point within the conductive path, resulting in resistive
switching phenomena. These results support the existing model attributing the memristance of
laser-fabricated graphene oxide memristors to the modification of a conductive path stoichiometry
inside the graphene oxide.The authors thank the support of the Spanish Ministry of Science, Innovation and Universities
under projects TEC2017-89955-P, TEC2017-84321-C4-3-R, MTM2017-88708-P and project PGC2018-098860-B-I00
(MCIU/AEI/FEDER, UE), and the predoctoral grant FPU16/01451
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