Abstract Background: Antiphospholipid syndrome (APS) is characterized by episodes of thrombosis, obstetric morbidity or both, associated with persistently positive antiphospholipid antibodies (aPL). Studying the profile of a rare disease in an admixed population is important as it can provide new insights for understanding an autoimmune disease. In this sense of miscegenation, Brazil is characterized by one of the most heterogeneous populations in the world, which is the result of five centuries of interethnic crosses of people from three continents. The objective of this study was to compare the clinical and laboratory characteristics of Brazilian vs. non-Brazilian primary antiphospholipid syndrome (PAPS) patients. Methods: We classified PAPS patients into 2 groups: Brazilian PAPS patients (BPAPS) and PAPS patients from other countries (non-BPAPS). They were compared regarding demographic characteristics, criteria and non-criteria APS manifestations, antiphospholipid antibody (aPL) profile, and the adjusted Global Antiphospholipid Syndrome Score (aGAPSS). Results: We included 415 PAPS patients (88 [21%] BPAPS and 327 [79%] non-BPAPS). Brazilian patients were significantly younger, more frequently female, sedentary, obese, non-white, and had a higher frequency of livedo (25% vs. 10%, p < 0.001), cognitive dysfunction (21% vs. 8%, p = 0.001) and seizures (16% vs. 7%, p = 0.007), and a lower frequency of thrombocytopenia (9% vs. 18%, p = 0.037). Additionally, they were more frequently positive for lupus anticoagulant (87.5% vs. 74.6%, p = 0.01), and less frequently positive to anticardiolipin (46.6% vs. 73.7%, p < 0.001) and anti-ß2-glycoprotein-I (13.6% vs. 62.7%, p < 0.001) antibodies. Triple aPL positivity was also less frequent (8% vs. 41.6%, p < 0.001) in Brazilian patients. Median aGAPSS was lower in the Brazilian group (8 vs. 10, p < 0.0001). In the multivariate analysis, BPAPS patients still presented more frequently with livedo, cognitive dysfunction and sedentary lifestyle, and less frequently with thrombocytopenia and triple positivity to aPL. They were also less often white. Conclusions: Our study suggests a specific profile of PAPS in Brazil with higher frequency of selected non-criteria manifestations and lupus anticoagulant positivity. Lupus anticoagulant (not triple positivity) was the major aPL predictor of a classification criteria event.

Resumo O estudo de aglomerantes alternativos ao cimento Portland, como os cimentos geopoliméricos, contribui para o desenvolvimento de materiais com diferentes propriedades. Com este objetivo, nesta pesquisa, foi avaliado experimentalmente o comportamento de vigas de concreto comparando com modelo numérico utilizando Elementos Finitos. Foram fabricadas duas vigas de concreto, uma utilizando cimento Portland e outra utilizando cimento geopolimérico. As vigas foram instrumentadas com LVDT´s e strain gauges para medir a deformação do concreto e do aço. A resistência à compressão do concreto geopolimérico foi 8% superior em relação ao concreto de cimento Portland (55 MPa e 51 MPa, respectivamente) e a tensão de ruptura a flexão também foi 8% superior para a viga de concreto geopolimérico (131 kN) em relação a viga de concreto de cimento Portland (121 kN). Mecanismos distintos de ruptura foram observados, com maior deformação plástica para viga de concreto geopolimérico, mostrando sua tenacidade. O concreto geopolimérico apresentou maior resistência de aderência à tração e maior coesão na interface com a armadura.

Abstract The study of alternative binders to Portland cement, such as geopolymer cements, offers the chance to develop materials with different properties. With this purpose, this study evaluated experimentally the mechanical behavior of a geopolymer concrete beam and compared to a Finite Element (FE) nonlinear numerical model. Two concrete beams were fabricated, one of Portland cement and another of metakaolin-based geopolymer cement. The beams were instrumented with linear variable differential transformers and strain gauges to measure the deformation of the concrete and steel. Values for the compressive strength of the geopolymer cement concrete was 8% higher than the Portland cement concrete (55 MPa and 51 MPa, respectively) and the tensile rupture strength was also 8% higher (131 kN) for the geopolymer concrete beam in relation to Portland cement concrete beam (121 kN). Distinct failure mechanisms were verified between the two samples, with an extended plastic deformation of the geopolymer concrete, revealing post-fracture toughness. The geopolymer concrete showed higher tensile strength and better adhesion in cement-steel interface.

We are currently in the process of calibration of a new cosmic ray detector called SciBar Cosmic Ray Telescope (SciCRT) located at the top of the Sierra Negra volcano at 4,600 m.a.s.l., in Eastern Mexico. The SciCRT will work mainly as a Solar Neutron and Muon Telescope, with a high angular resolution (~ 1°), but it will also serve as a gamma ray and hadron shower detector. The mini-SciCR is a prototype of the SciCRT, it uses the same scintillator bars and recording hardware, the size of the mini-SciCR is 1/1568 compared with the SciCRT. In this paper we will report the main results obtained with the mini-SciCR that was operating at the top of the Sierra Negra volcano from October 2010 to July 2012. Our main aims were to show the appropriate performance of all the detector systems and to develop a tecnique to separate the flux of soft and hard secondary cosmic rays with the help of a Monte Carlo simulation, our energy range of interest is from 100 MeV to a few GeV. Aditionally we will report results with a modification of the detector setup that helped to confirm the correct identification of the particle species.

We present a summary of current research on planetary nebulae and their central stars, and related subjects such as atomic processes in ionized nebulae, AGB and post-AGB evolution. Future advances are discussed that will be essential to substantial improvements in our knowledge in the field.

Se presenta un resumen del estado actual de la investigación sobre las nebulosas planetarias y sus estrellas centrales, y temas relacionados como los procesos atómicos en nebulosas ionizadas, y la evolución de las estrellas de la rama gigante asintótica y post-gigante asintótica. Se discuten los avances futuros que serán necesarios para incrementar sustancialmente nuestro conocimiento en este campo.

Correlations between the oxidation potentials and the stretching frequencies of the carbonyl groups in the fac-tricarbonylbromo(polypyridyl)rhenium(I) complexes with respect to the BrRe(CO)5 precursor are discussed

Correlaciones entre los potenciales de oxidación y las frecuencias de estiramiento de los grupos carbonilos son discutidas en complejos tricarbonilbromo(polipiridilo) de renio(I), respecto al precursor BrRe(CO)5.