Tailoring optical fields emitted by nanometric sources

Here we study a simple way of controlling the emitted fields of sub-wavelength nanometric sources. The system consists of arrays of nanoparticles (NPs) embedded in optical active media. The key concept is the careful tuning of NP's damping factors, which changes the eigenmode's decay rates of the whole array. This, at long time, leads to a locking of relative phases and frequencies of individual localized-surfaces-plasmons (LSPs) and, thus, controlls the emitted field. The amplitude of the LSP's oscillations can be kept constant by embedding the system in optical active media. In the case of full loss compensation, this implies that, not only the relative phases, but also the amplitudes of the LSPs remain fixed, leading us, additionally, to interpret the process as a new example of synchronization. The proposed approach can be used as a general way of controlling and designing the electromagnetic fields emitted by nanometric sources, which can find applications in optoelectronic, nanoscale lithography and probing microscopy

The role of the water voles (Arvicola, Rodentia) in the Quatemary

Arvicolids are rodents which have molars with a morphology formed by a sequence of enamel folds similar to the curve y = sin f(x). The morphology of the crown of the first lower molar (mi) of living species of Arvicola (large voles) is identified with six criteria, irrespective of tooth size. When rootless arvicolid fossil communities are analysed, it can be seen that the mi morphology of Arvicola is present in those communities represented by specimens of small size at the beginning of the Quaternary. Before this data was known, the presence of Arvicola communities could only be detected in the second half of the Quaternary, when the specimens were comparable to the large size characterising living species. The existence of communities of small-sized Arvicola at the beginning of the Quaternary implies that the mi of Arvicola undergoes a continuous and accelerated growth throughout the entire Quatemary, which allows representatives the genus to be used as a chronological tool. These data mean that it is necessary to change the concept of the genus Allophaiomys and to formulate a new classification to reflect evolutionary relationships of quatemary arvicolids.Los arvicólidos son roedores que tienen la morfología de la corona de los dientes formada por una secuencia de pliegues de esmalte que se asemeja a la curva y=sen f(x). Las especies actuales del género Arvicola cumplen en la morfología del molar mI, seis criterios que son independientes de la talla. El examen de las poblaciones de arvicólidos sin raíz, procedentes del Pleistoceno inferior, indica la existencia de molares con una morfología idéntica a la de los ejemplares vivos de Arvicola, pero con menor talla. La existencia de esta identidad permite proponer la hipótesis de poblaciones primitivas del género Arvicola con pequeña talla durante el Pleistoceno Inferior. Estas han pasado desapercibidas entre las poblaciones de Allophaiomys. a causa de su identidad morfológica entre ambos. La hipótesis de la existencia de Arvicola en el Pleistoceno Inferior supone un profundo cambio en el concepto de Allophaiomys como género y convierte la talla de Arvicola, por su continuo crecimiento durante todo el Pleistoceno, en un útil instrumento cronológico

Human Rights, Exploitation, and Genetic Use Restriction Technology: Sowing the Seeds of Reason in the Field of the Terminator Debate.

The current debate concerning genetically modified (GM) crops is primarily focused on the negative consequences that the production and consumption of GM foods could have on people and the environment. Adding to the list of concerns is the multinational agrochemical corporations\u27 plan to implement GURTs (Genetic Use Restriction Technologies) to prohibit the unauthorized use of certain genetically modified plant varieties. Several activist groups perceive the potential implementation of GURTs to be a threat to resource-poor farmers since this technology (which the activists call Terminator Technology) may be used to wrongfully exploit resource-poor farmers in the name of economic gain. In this thesis, I argue that multinational agrochemical corporations will not necessarily be infringing upon the rights of resource-poor farmers nor with they be wrongfully exploiting such farmers through the implementation of GURTs. Given that the primary targets for implementing GURTs are currently modified plant varieties, and most resource-poor farmers are unable to afford GM seeds, multinational agrochemical corporations will not have the opportunity to form a relation with these farmers and therefore would not be able to use them as a mere means to maximizing seed industry profits. I conclude that the implementation of GURTs may be construed as immoral on some grounds, but it is not wrongfully exploitative

La morfología de la línea de esmalte en los molares de los roedores muroideos es explicada mediante una red hexagonal

The crown enamel line of muroids rodent has geometric traces that coincide exactly with an equilateral triangular lattice. This finding helps to explain the muroids dental pattern from a novel perspective in molar morphology that it is based on hexagonal structures. The adult traces imply that the morphology of the teeth mammals is consequence of a morphogenetic process. This is the study of the hexagonal lattice marks observed in the enamel line, and therefore called odontohexasymmetry. The particular dental pattern, which it is passed down from parents to offspring, it start with a genetic algorithm coded in DNA. This includes a system of intelligent self-control, which during the morphogenesis coordinates the morphology of the all teeth of a specimen to get the best occlusion. The hypothesis of mitosis area loop-development (Ruiz Bustos, 2004a, 2005, 2006 and 2007) explains that in early morphogenesis stage, the initial mass-cell (basal mitosis area), it is repeated in a loop, thereby forming all other mitosis areas of the tooth. At the end of the morphogenesis, the biomineralization processes transform the mitosis areas in the cusps crown.La línea de esmalte observada en la corona de los roedores muroideos tiene formas geométricas que coinciden exactamente con una red plana triangular equilateral. Esta conclusión ayuda a explicar el modelo dental de los muroideos con una nueva perspectiva denominada odontohexasimetria, fundamentada en las formas hexagonales observadas en la línea de esmalte. La morfología de la corona del diente de los mamíferos es heredada de padres a hijos. Esto infiere la existencia en cada espécimen de un autocontrol inteligente codificado en el genoma, que coordina la morfología de los dientes durante el desarrollo embriológico y su oclusión. La hipótesis del desarrollo el bucle de las áreas de mitosis (Ruiz Bustos, 2004a, 2005, 2006 y 2007) propone, que en los momentos iniciales de la morfogénesis, es observada una masa de células en mitosis (área de mitosis de basal). Esta es repetida en un bucle, hasta constituir todas las restantes áreas de mitosis del diente. Al final de la morfogénesis, el proceso de biomineralización transforma las áreas de mitosis en los tubérculos de la corona del diente