Fermions via spinor-valued one-forms

Spinor-valued one-forms (Rarita-Schwinger fields) are normally used in the context of supergravity, where they describe spin 3/2 particles (gravitinos). Indeed, when decomposed into irreducible representations of the Lorentz group such a field contains both a spin 1/2 and a spin 3/2 component, and the Rarita-Schwinger Lagrangian is designed to make only the spin 3/2 propagate. We point out that the opposite construction is also possible, and give a spinor-valued one-form field Lagrangian that describes a propagating spin 1/2 particle.Comment: 23 pages, no figure

Cuidado humanizado na área da saúde

Nós profissionais de saúde estamos tradicionalmente mais vinculados ao humanismo em relação à outras disciplinas, por nossa formação e porque trabalhamos de maneira muito direta com doentes, além de termos que criar contextos que sirvam como pontes para gerar humanismo1. Em sentido genérico e aplicado à saúde, o humanismo refere-se aos atos de assistência, suporte, ajuda e de conservação que apóiam a pessoa ou grupos com necessidades, para poder melhorar suas condições de vida. Também fazemos referência a essa atitude de tratar as pessoas com dignidade e respeito, baseados em um modelo de relação e assistência centrada na pessoa e no tratamento do ser humano em seu conjunto e de uma maneira integral

Nanoestructuras híbridas fe3o4-ag-y2o3:eu3+: evaluación de sus propiedades físicas y su posible aplicación en Sensado

Tesis Doctoral del Posgrado en Ciencia de MaterialesSe desarrolló un material híbrido a partir de estructuras unidimensionales (1D) de óxido de itrio dopado con varias concentraciones de europio (Y2O3:Eu3+), decoradas con magnetita (Fe3O4) y plata (Ag) nanoestructurada, utilizando un método de síntesis hidrotermal. Cada uno de los materiales se sintetizó por separado y se caracterizó por diferentes técnicas; espectroscopia Infrarroja (IR), espectroscopia Raman (Rm), espectroscopia de fluorescencia (PL), difracción de rayos X (XRD), microscopía electrónica de barrido (SEM), espectroscopia de rayos X de energía dispersiva (EDS), microscopía electrónica de transmisión (TEM), microscopía electrónica de transmisión por barrido (STEM) y magnetometría (Mg). Una vez caracterizados los materiales por separado, se sintetizó y caracterizó el material híbrido. Los resultados muestran que se puede obtener nanobarras de Y2O3:Eu3+ decoradas con nanopartículas de Fe3O4-Ag, las cuales presentan una mejora en la respuesta luminiscente al aplicar un campo magnético externo.The authors acknowledges the Kleberg Advanced Microscopy Center (KAMiC) and NIH RCMI Nanotechnology and Human Health Core (Grant 5G12RR013646-12) at UTSA; UAEMex Grant 3688/20147CIB and CONACYT Grant 280518

On F-Algebroids and Dubrovin's Duality

In this note we introduce the concept of F-algebroid, and give its elementary properties and some examples. We provide a description of the almost duality for Frobenius manifolds, introduced by Dubrovin, in terms of a composition of two anchor maps of a unique cotangent F-algebroid.Comment: 13 pages; v2 has small changes, it has improved exposition. Revised version to appear in: "Archivum Mathematicum

An integrative approach for modeling and simulation of Heterocyst pattern formation in Cyanobacteria strands

A comprehensive approach to cellular differentiation in cyanobacteria is developed. To this aim, the process of heterocyst cell formation is studied under a systems biology point of view. By relying on statistical physics techniques, we translate the essential ingredients and mechanisms of the genetic circuit into a set of differential equations that describes the continuous time evolution of combined nitrogen, PatS, HetR and NtcA concentrations. The detailed analysis of these equations gives insight into the single cell dynamics. On the other hand, the inclusion of diffusion and noisy conditions allows simulating the formation of heterocysts patterns in cyanobacteria strains. The time evolution of relevant component concentrations are calculated allowing for a comparison with experiments. Finally, we discuss the validity and the possible improvements of the model.Comment: 20 pages (including the supporting information), 8 figure

2D sigma models and differential Poisson algebras

We construct a two-dimensional topological sigma model whose target space is endowed with a Poisson algebra for differential forms. The model consists of an equal number of bosonic and fermionic fields of worldsheet form degrees zero and one. The action is built using exterior products and derivatives, without any reference to any worldsheet metric, and is of the covariant Hamiltonian form. The equations of motion define a universally Cartan integrable system. In addition to gauge symmetries, the model has one rigid nilpotent supersymmetry corresponding to the target space de Rham operator. The rigid and local symmetries of the action, respectively, are equivalent to the Poisson bracket being compatible with the de Rham operator and obeying graded Jacobi identities. We propose that perturbative quantization of the model yields a covariantized differential star product algebra of Kontsevich type. We comment on the resemblance to the topological A model.Comment: 20 page