Juan Ramón Manzanilla Dorantes - Academia.edu (original) (raw)

Papers by Juan Ramón Manzanilla Dorantes

Canadian Journal of Microbiology, 2012

In Escherichia coli cells, an increase in temperature induces immediate DNA relaxation, followed ... more In Escherichia coli cells, an increase in temperature induces immediate DNA relaxation, followed by the fast recovery of DNA supercoiling. DNA gyrase, proteins synthesized during heat stress, and chaperone DnaK have been proposed to participate in this recovery. However, the mechanism of DNA supercoiling recovery has not been completely elucidated. The results presented here suggest that in cells exposed to severe heat-shock stress, DNA supercoiling levels are recovered by the reactivation of DNA gyrase. This reactivation involves solubilization of a fraction of protein GyrA present in protein aggregates, by the bichaperone DnaK-ClpB system.

Progress in Nuclear Energy, 2013

In this paper the transmutation of light water reactors (LWR) spent fuel is analyzed. The system ... more In this paper the transmutation of light water reactors (LWR) spent fuel is analyzed. The system used for this study is the fusion-fission transmutation system (FFTS). It uses a high energy neutron source produced with deuterium-tritium fusion reactions, located in the center of the system, which is surrounded by a fission region composed of nuclear fuel where the fissions take place. In this study, the fuel of the fission region is obtained from the recycling of LWR spent fuel. The MCNPX Monte Carlo code was used to setup a model of the FFTS. Two fuel types were analyzed for the fissile region: the mixed oxide fuel (MOX), and the inert matrix fuel (IMF). Results show that in the case of the MOX fuel, an important Pu-239 breeding is achieved, which can be interesting from the point of view of maximal uranium utilization. On the contrary, in the case of the IMF fuel, high consumption of Pu-239 and Pu-241 is observed, which can be interesting from the point of view of non-proliferation issues. A combination of MOX and IMF fuels was also studied, which shows that the equilibrium of actinides production and consumption can be achieved. These results demonstrate the versatility of the fusion-fission hybrid systems for the transmutation of LWR spent fuel.

Relaciones Estudios de Historia y Sociedad

Este trabajo aborda la federalización educativa en el municipio de Espita, en el Estado de Yucatá... more Este trabajo aborda la federalización educativa en el municipio de Espita, en el Estado de Yucatán de 1922 a 1935. La federalización educativa centralizadora fue precedida por la disputa entre los gobiernos municipal y estatal. Durante el siglo XIX y principios del XX, la Iglesia, las comunidades y los ayuntamientos dejaron de tener injerencia en el sistema escolar. En Espita, la federalización educativa se dio por la concurrencia y conflicto entre redes escolares en la zona urbana y por complementariedad con la instalación de escuelas en las haciendas donde no las había, en un proceso de rápida expansión de la red federal educativa.

Canadian Journal of Microbiology, 2012

In Escherichia coli cells, an increase in temperature induces immediate DNA relaxation, followed ... more In Escherichia coli cells, an increase in temperature induces immediate DNA relaxation, followed by the fast recovery of DNA supercoiling. DNA gyrase, proteins synthesized during heat stress, and chaperone DnaK have been proposed to participate in this recovery. However, the mechanism of DNA supercoiling recovery has not been completely elucidated. The results presented here suggest that in cells exposed to severe heat-shock stress, DNA supercoiling levels are recovered by the reactivation of DNA gyrase. This reactivation involves solubilization of a fraction of protein GyrA present in protein aggregates, by the bichaperone DnaK-ClpB system.

Progress in Nuclear Energy, 2013

In this paper the transmutation of light water reactors (LWR) spent fuel is analyzed. The system ... more In this paper the transmutation of light water reactors (LWR) spent fuel is analyzed. The system used for this study is the fusion-fission transmutation system (FFTS). It uses a high energy neutron source produced with deuterium-tritium fusion reactions, located in the center of the system, which is surrounded by a fission region composed of nuclear fuel where the fissions take place. In this study, the fuel of the fission region is obtained from the recycling of LWR spent fuel. The MCNPX Monte Carlo code was used to setup a model of the FFTS. Two fuel types were analyzed for the fissile region: the mixed oxide fuel (MOX), and the inert matrix fuel (IMF). Results show that in the case of the MOX fuel, an important Pu-239 breeding is achieved, which can be interesting from the point of view of maximal uranium utilization. On the contrary, in the case of the IMF fuel, high consumption of Pu-239 and Pu-241 is observed, which can be interesting from the point of view of non-proliferation issues. A combination of MOX and IMF fuels was also studied, which shows that the equilibrium of actinides production and consumption can be achieved. These results demonstrate the versatility of the fusion-fission hybrid systems for the transmutation of LWR spent fuel.

Relaciones Estudios de Historia y Sociedad

Este trabajo aborda la federalización educativa en el municipio de Espita, en el Estado de Yucatá... more Este trabajo aborda la federalización educativa en el municipio de Espita, en el Estado de Yucatán de 1922 a 1935. La federalización educativa centralizadora fue precedida por la disputa entre los gobiernos municipal y estatal. Durante el siglo XIX y principios del XX, la Iglesia, las comunidades y los ayuntamientos dejaron de tener injerencia en el sistema escolar. En Espita, la federalización educativa se dio por la concurrencia y conflicto entre redes escolares en la zona urbana y por complementariedad con la instalación de escuelas en las haciendas donde no las había, en un proceso de rápida expansión de la red federal educativa.