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Quando há exposição à radiação ionizante, a probabilidade de desenvolver um dano por efeito estocástico aumenta, e um dos mais temidos efeitos estocásticos é o câncer. Os cálculos realizados, a partir de dados obtidos com a população de Hiroshima, mostraram que esses efeitos não possuem dose limiar. Assim é impossível prever, que um determinado valor de dose, induzirá um dano, e por isso, as doses, devem ser sempre limitadas. As exposições médicas têm contribuído para o aumento da dose recebida pelas populações de países, como o Brasil. Isto se deve ao fato, de que, houve um aumento nos procedimentos intervencionistas que utilizam radiações ionizantes. O que tem preocupado pesquisadores, já que, muitas empresas não se adequaram as normas de proteção radiológica. O uso adequado de equipamentos de proteção individual reduz a exposição de pacientes e profissionais. Profissionais treinados e conhecedores das normas são capazes de escolher a blindagem adequada para cada tipo de procedimento. Assim avaliamos o conhecimento e a prática dos profissionais em radiologia, na proteção de pacientes, que não podem ser removidos do ambiente nos exames de raios-X e verificamos se o treinamento melhora a qualidade desse serviço. Concluiu-se que há deficiência no conhecimento das normas e falhas na proteção de pacientes, e que, o treinamento no que diz respeito à proteção radiológica, aumenta o nível de conhecimento teórico dos profissionais envolvidos, além de melhorar as suas práticas, com relação à proteção, reduzindo as doses e minimizando os riscos envolvidos nas exposições médicas.

Anthracene derivatives are an interesting class of compounds and modifications in the anthracene ring, producing different compounds with different properties. Structural analysis of anthracene derivatives with modifications in position 9,10 of the aromatic ring is necessary in order to obtain information about its properties. The introduction of groups with polar substituents increases the possibility to modify the molecule lipophilicity, corroborating its use as bioimaging probes. Anthracene derivatives are used in many biochemical applications. These compounds can react with molecular singlet oxygen [O2 (1Δg)], a reactive oxygen species, through the Diels–Alder reaction [4 + 2] to form the respective endoperoxide and to be used as a chemical trap in biological systems. Thus, the structural and crystalline characterizations of two anthracene derivatives are presented in this work to obtain information about their physical-chemical properties. The compounds were characterized by Fourier-transform infrared spectroscopy, thermogravimetric analyses and scanning electron microscopy. The molecular structures of the compounds were studied by the Density Functional Theory, M06-2X/6-311++G(d,p) level of theory in the gas phase. From the results obtained for the frontier molecular orbitals, HOMO and LUMO, and from the Molecular Electrostatic Potential map, it was possible to predict the chemical properties of both compounds. The supramolecular arrangements were also theoretically studied, whose molecules were kept fixed in their crystallographic positions, through the natural bonding orbitals analysis to check the stability of interactions and the quantum theory of atoms in molecules to verify the type of intermolecular interaction between their molecules, as well as how they occur.

Fine aggregate matrix (FAM) has been regarded as a key constituent of asphalt mixtures. Although several design methods have been recently proposed to prepare FAM specimens that represent the materials contained within the asphalt concretes, the volumetric characteristics of FAM may not be uniformly distributed within samples compacted using devices such as the Superpave gyratory compactor (SGC). This can mislead the mechanical analyses conducted with testing specimens that are typically extracted from different locations of the compacted samples, as they can present varying volumetric characteristics. This study employs the advanced micro-computed tomography (CT) scan technique to evaluate the air void distribution within FAM specimens extracted from different locations of SGC samples compacted with distinct air void contents. Rheological tests are performed in a dynamic shear rheometer to determine the dynamic shear modulus of the testing specimens. A statistical analysis is conducted to evaluate potential correlations between the volumetric and the rheological characteristics of the FAMs and to identify locations within the SGC samples from which small cylindrical specimens with similar characteristics can be extracted and used for testing. The adoption of advanced techniques such as the CT scan is essential for the advancement of the knowledge on the complex characteristics of asphalt mixtures, and may facilitate the fabrication of FAMs that are more representative of those that comprise asphalt concretes, as well as allow the use of similar replicates in mechanical tests.

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This study employs the advanced X-ray microtomography technique to evaluate the open and closed porosity geometry within fine aggregate matrix specimens extracted from different locations of SGC samples compacted with distinct densities. The adoption of advanced techniques such as the X-ray microtomography facilitate the fabrication of FAMs that are more representative of those that comprise asphalt concretes, as well as allow the use of similar replicates in mechanical tests. In addition, the traditional porosity assessment methods are well documented, but provide only global average results for the entire sample. In this context, X-ray microtomography stands out because, besides porosity information, pore distribution and a series of other parameters related to the internal structure of the object can be evaluated. This study evaluated the geometry of open and closed pores of FAM specimens extracted from different locations of SGC compacted samples. From the results and analyses, it can be concluded that the shape of the closed pores is spherical and the shape of the open pores is cylindrical for the SGC samples compressed with 2.26 g/cm3, 2.34 g/cm3 and 2.44 g/cm3.

This work describes molecular structures of chalcones 2'-Hydroxy-4',6'-dimethyl-2-chlorochalcone and 2'-Hydroxy-4',6'-dimethyl-4-chlorochalcone and overlap of these structures in order to detect the change in planarity. The Hirshfeld Surface analysis to investigate when the position of the atom the chlorine in the aromatic ring is changed and how does this change influence in the properties of the organic compound. The geometric molecular were obtained through the DFT/M06-2X/6-311++G(2d, 2p) theory level. Frontier Molecular Orbital, NBO and MEP map were determined, in order to observe the information related to charge transfer in the molecule. The interactions between the molecules were verified with the aid of QTAIM.