Evaluation of optical transmission across the ITER hard x-ray monitor system designed for the first plasma scenarios.

Hard x-ray (HXR) spectroscopy is applied for diagnostics of runaway electrons in nuclear fusion reactors. The scintillation counter is one of the most commonly used types of detectors for HXR spectroscopy. It consists of a detector that emits light when excited by HXR radiation (scintillator) directly coupled to a PMT (Photomultiplier Tube) that converts light pulses into an electrical signal. This type of detector is commonly used in existing tokamaks, such as Joint European Torus (JET), Experimental Advanced Superconducting Tokamak (EAST), Compact Assembly (COMPASS), and Axially Symmetric Divertor Experiment (ASDEX-U). In all these cases, the scintillator is directly coupled to the PMT to provide the best possible light transmission efficiency. The Hard X-ray Monitor (HXRM) is one among the first plasma diagnostic systems at ITER that provides information about the energy distribution of runaway electrons inside a tokamak by HXR spectroscopy. This system also uses a scintillator and a PMT as a detector. Due to the heavy shielding of the blanket modules, vacuum vessel, and port-plugs, it is not possible to assemble the scintillator outside the tokamak vacuum vessel. The PMT detector cannot be installed in the close vicinity of the tokamak due to either the significant magnetic field or temperature. A possible solution is to decouple the scintillator from the PMT and place the PMT inside the port-cell. Light pulses will be transmitted to the PMT via a 12 m long optical fiber bundle. Evaluation of the optical transmission was carried out to assess the performance of the HXR monitor and verify possible problems related to the PMT pulse discrimination under low light conditions.

Randomised in situ clinical trial investigating self-assembling peptide matrix P11-4 in the prevention of artificial caries lesions.

The aim was to investigate the ability of self-assembling Peptide P11-4 Matrix (SAPM) to remineralize artificial initial caries lesions compared to the use of fluoride varnish. Volunteers were recruited for this randomised, cross-over in situ trial. Bovine specimens, half including orthodontic brackets, were recessed on the buccal aspects of mandibular appliances. Specimens included internal sound enamel control, a demineralised control and a part exposed during the in situ phase. Each phase lasted four weeks, followed by a one-week washout. Treatment groups were: A: negative control, no treatment,B: positive control, 22,600 ppm fluoride varnish,C: test group, 1,000 ppm SAPM. Laser fluorescence values (LF) were measured before/after demineralisation, and after the in situ period. Micro-CT analysis was used to assess mineral changes within the specimens after the in situ phase. In specimens without brackets, ΔLF values after in situ phase were: A: +5.28, B: +0.85, C: -2.89. Corresponding ΔLF for specimens with brackets were: A: +5.77, B: +1.30, C: -3.15. LF-values between groups significantly differed from each other (p < 0.0001) after the in situ phase. Micro-CT analysis yielded no significant difference among groups for specimens without brackets. For specimens with brackets, the test group showed significantly more remineralisation than the negative (p = 0.01) and positive control (p = 0.003). Within the limitations of the study, SAPM showed prevention of caries and remineralisation of enamel around orthodontic brackets.

A estrutura do poder conjugal: uma análise de duas culturas em duas épocas / The structure of marital power: an analysis of two cultures in two different periods

Este artigo estuda a estrutura de poder em famílias, baseado nas respostas fornecidas por duas amostras de casais residentes no Rio de Janeiro. Constitui, essencialmente, uma réplica de um estudo conduzido por Centers et al. (1971) com casais americanos residentes em Los Angeles. Para efeitos de comparaçäo transcultural, além dos dados de Centers et alii, os reportados por Blood & Wolfe (1960), obtidos com uma amostra de esposas residentes em Detroit, foram também considerados. Cento e trinta e quatro casais foram entrevistados em 1988 e 96, em 1989. O instrumento de pesquisa consistia de 12 situaçöes de decisäo na esfera familiar, as quais os respondentes deveriam dizer quem nelas tinha a última palavra. Perguntas relativas a autoritarismo, satisfaçäo conjugal, idade, classe social e nível educacional foram incluídas. Os resultados indicaram uma queda do poder decisório do marido, quando comparados com os obtidos há mais de duas década por Blood & Wolfe e Centers et alii. A idade se correlacionou positivamente com o maior poder do marido. Satisfaçäo conjugal e autoritarismo näo mostraram associaçöes com poder do marido, e as demais variáveis demográficas consideradas, além de idade, demonstraram associaçöes ocasionais. Nota-se, ainda, uma preferência por uma estrutura autonômica de poder conjugal. Estes resultados säo discutidos a luz das transformaçöes sociais decorrentes da revoluçäo sexual, das mudanças dos papéis sexuais e da possível crise de identidade masculina