Recommendations to reduce hand exposure for standard nuclear medicine procedures

The optimization of the extremity dosimetry of medical staff in nuclear medicine was the aim of the Work Package 4 (WP4) of the ORAMED project, a Collaborative Project (2008-2011) supported by the European Commission within its 7th Framework Programme. Hand doses and dose distributions across the hands of medical staff working in nuclear medicine departments were evaluated through an extensive measurement program involving 32 hospitals in Europe and 139 monitored workers. The study included the most frequently used radionuclides, (99m)Tc- and (18)F-labelled radiopharmaceuticals for diagnostic and (90)Y-labelled Zevalin (R) and DOTATOC for therapy. Furthermore, Monte Carlo simulations were performed in different predefined scenarios to evaluate separately the efficacy of different radiation protection measures by comparing hand dose distributions according to various parameters. The present work gives recommendations based on results obtained with both measurements and simulations. This results in nine practical recommendations regarding the positioning of the dosemeters for an appropriate skin dose monitoring and the best protection means to reduce the personnel exposure.

Proposed gravitational wave observatory based on solid elastic spheres

Spherical gravitational wave (GW) detectors offer a wealth of so far unexplored possibilities to detect gravitational radiation. We find that a sphere can be used as a powerful testbed for any metric theory of gravity, not only general relativity as considered so far, by making use of a deconvolution procedure for all the electric components of the Riemann tensor. We also find that the spheres cross section is large at two frequencies, and advantageous at higher frequencies in the sense that a single antenna constitutes a real xylophone in its own. Proposed GW networks will greatly benefit from this. The main features of a two large sphere observatory are reported.

Hollow sphere as a detector of gravitational radiation

The most important features of the proposed spherical gravitational wave detectors are closely linked with their symmetry. Hollow spheres share this property with solid ones, considered in the literature so far, and constitute an interesting alternative for the realization of an omnidirectional gravitational wave detector. In this paper we address the problem of how a hollow elastic sphere interacts with an incoming gravitational wave and find an analytical solution for its normal mode spectrum and response, as well as for its energy absorption cross sections. It appears that this shape can be designed having relatively low resonance frequencies (~ 200 Hz) yet keeping a large cross section, so its frequency range overlaps with the projected large interferometers. We also apply the obtained results to discuss the performance of a hollow sphere as a detector for a variety of gravitational wave signals.

De la razón vital a la razón poética: el logos de las cosas

La importante presencia del mundo de la objetualidad en el pensamiento de MaríaZambrano constituye una de sus características más destacables; la atención que en su obra reciben las "cosas" no sólo hace de éstas un tema zambraniano, sino que parece aludir a unrasgo de la forma de racionalidad que la autora introduce: la "razón poética" podría definirse por su capacidad de acoger el logos de las cosas, accediendo así a su sentido. Estaforma de racionalidad, coherente con su planteamiento teórico, pone de manifiesto una distancia con el de Ortega y Gasset que permite cuestionar las relaciones entre ambos autoresy abordar si la "razón poética" es sólo un desarrollo de la "razón vital" o presenta, desde el inicio, una identidad propia, en tomo a la que se articula su aportación.

O dever e a aspiração em crianças brasileiras

Este trabalho teve por objetivo investigar a caracterização do "erro educacional fundamental", com base na distinção entre a moralidade do dever e a da aspiração.Participaram como sujeitos 120 crianças da pré-escola e da 4ª série do ensino fundamental, de ambos os sexos e de diferentes classes sociais. Como instrumento de análise, foram utilizadas seis histórias: duas do domínio moral, duas do pró-social e duas do acadêmico. Foi feita análise das previsões das "reações dos professores" em relação aos personagens transgressores e cumpridores de uma norma e das "reações emocionais dos personagens transgressores". Os resultados evidenciam que houve diferença significativa nas respostas para "as reações dos professores", em relação à idade (domínio pró-social e acadêmico) e ao sexo (domínio acadêmico). Quanto à análise das "reações emocionais dos personagens transgressores", verificou-se que a idade influenciou expressivamente as respostas no domínio pró-social. Finalmente foram discutidas implicações teóricas e educacionais dos resultados.