The first analytical expression to estimate photometric redshifts suggested by a machine

We report the first analytical expression purely constructed by a machine to determine photometric redshifts ($z_{\rm phot}$) of galaxies. A simple and reliable functional form is derived using $41,214$ galaxies from the Sloan Digital Sky Survey Data Release 10 (SDSS-DR10) spectroscopic sample. The method automatically dropped the $u$ and $z$ bands, relying only on $g$, $r$ and $i$ for the final solution. Applying this expression to other $1,417,181$ SDSS-DR10 galaxies, with measured spectroscopic redshifts ($z_{\rm spec}$), we achieved a mean $\langle (z_{\rm phot} - z_{\rm spec})/(1+z_{\rm spec})\rangle\lesssim 0.0086$ and a scatter $\sigma_{(z_{\rm phot} - z_{\rm spec})/(1+z_{\rm spec})}\lesssim 0.045$ when averaged up to $z \lesssim 1.0$. The method was also applied to the PHAT0 dataset, confirming the competitiveness of our results when faced with other methods from the literature. This is the first use of symbolic regression in cosmology, representing a leap forward in astronomy-data-mining connection.Comment: 6 pages, 4 figures. Accepted for publication in MNRAS Letter

A reforma agrária no segundo mandato de Fernando Henrique Cardoso.

Já no primeiro mandato do presidente Fernando Henrique Cardoso, a política agrária sofreu reorientações significativas, que marcariam seu segundo mandato, a partir da nomeação de Raul Jungmann como ministro do Desenvolvimento Agrário. A reforma agrária finalmente encontrou o seu sujeito, a agricultura familiar, e o Estado encontrou a sua missão agrária como gestor do território. Foram assim estabelecidas as bases concretas para o exercício da função social da propriedade, recuperando o Estado, na prática, o domínio eminente do território do país. Importante providência nesse sentido foi a anulação dos títulos irregulares de propriedade de sessenta milhões de hectares de terra. O governo firmou a prerrogativa do Estado de "rotinizar" a redistribuição da terra concentrada e regular e assegurar o direito de propriedade em associação com a dupla alternativa de dois modelos agrícolas conviventes: o agronegócio e a agricultura familiar

Acidente com hipoclorito de sódio

A redução do número de microrganismos presentes nos canais radiculares é fundamental para o sucesso da terapia endodôntica e, para conseguir isto, os Médicos Dentistas utilizam substâncias químicas. O hipoclorito de sódio é uma das principais substâncias químicas utilizadas como auxiliar na preparação do sistema de canais radiculares, dada a sua capacidade de dissolução da matéria orgânica e o seu efeito anti-microbiano. Porém, durante o uso deste irrigante pode ocorrer algum imprevisto como um acidente ou uma complicação e o Médico Dentista deve ter conhecimento suficiente para prevenir estas situações e saber também tratá-las quando necessário. O objectivo deste trabalho é realizar uma revisão na literatura sobre o correto manuseamento do hipoclorito de sódio e também descrever os acidentes/complicações que podem advir da utilização do mesmo, mostrando aos Médicos Dentistas a importância de conhecer as suas propriedades, para saber evitar/lidar com estas situações indesejáveis.Reducing the number of microorganisms present in the root canals system is critical to the success of endodontic therapy, and in order to do this, Dentists use chemicals. Sodium hypochlorite is one of the main chemical substances used as a valuable aid in the shaping of the root canal system, due to its dissolution capacity of organic matter and its antimicrobial effect. However, during the use of this irrigant there may be some unforeseen as an accident or a complication and the Dentist must have sufficient knowledge to prevent such situations and also to know how to treat them when they happen. The objective of this work is to review the literature on the correct handling of sodium hypochlorite and also to describe the accidents / complications that can occur when using this irrigant, showing to the clinicians the importance of knowing their properties, in order to know how to avoid and deal with these undesirable situations

Spectral Synthesis of Star-forming Galaxies in the Near-Infrared

The near-infrared spectral region is becoming a very useful wavelength range to detect and quantify the stellar population of galaxies. Models are developing to predict the contribution of TP-AGB stars, that should dominate the NIR spectra of populations 0.3 to 2 Gyr old. When present in a given stellar population, these stars leave unique signatures that can be used to detect them unambiguously. However, these models have to be tested in a homogeneous database of star-forming galaxies, to check if the results are consistent with what is found from different wavelength ranges. In this work we performed stellar population synthesis on the nuclear and extended regions of 23 star-forming galaxies to understand how the star-formation tracers in the near-infrared can be used in practice. The stellar population synthesis shows that for the galaxies with strong emission in the NIR, there is an important fraction of young/intermediate population contributing to the spectra, which is probably the ionisation source in these galaxies. Galaxies that had no emission lines measured in the NIR were found to have older average ages and less contribution of young populations. Although the stellar population synthesis method proved to be very effective to find the young ionising population in these galaxies, no clear correlation between these results and the NIR spectral indexes were found. Thus, we believe that, in practice, the use of these indexes is still very limited due to observational limitations.Comment: Accepted for publication on MNRAS. 21 pages, 14 figures, 2 table

Nuclear and Extended Spectra of NGC 1068 - II: Near-Infrared Stellar Population Synthesis

We performed stellar population synthesis on the nuclear and extended regions of NGC 1068 by means of near-infrared spectroscopy to disentangle their spectral energy distribution components. This is the first time that such a technique is applied to the whole 0.8 - 2.4 micron wavelength interval in this galaxy. NGC 1068 is one of the nearest and probably the most studied Seyfert 2 galaxy, becoming an excellent laboratory to study the interaction between black holes, the jets that they can produce and the medium in which they propagate. Our main result is that traces of young stellar population are found at ~ 100 south of the nucleus. The contribution of a power-law continuum in the centre is about 25%, which is expected if the light is scattered from a Seyfert 1 nucleus. We find peaks in the contribution of the featureless continuum about 100 - 150 pc from the nucleus on both sides. They might be associated with regions where the jet encounters dense clouds. Further support to this scenario is given by the peaks of hot dust distribution found around these same regions and the H2 emission line profile, leading us to propose that the peaks might be associate to regions where stars are being formed. Hot dust also has an important contribution to the nuclear region, reinforcing the idea of the presence of a dense, circumnuclear torus in this galaxy. Cold dust appears mostly in the south direction, which supports the view that the southwest emission is behind the plane of the galaxy and is extinguished very likely by dust in the plane. Intermediate age stellar population contributes significantly to the continuum, specially in the inner 200 pc.Comment: 9 pages, 8 figures. Accepted for publication at MNRA

Environment-Friendly Flame Retardants for Bio-Based Polyurethanes

Finding alternative ways to decrease the large consumption of non-renewable resources has been one of the greatest challenges faced by the industry and academia. The trend of using bio-renewable-based materials is an interesting alternative to tackle environmental issues as well as provide economically viable materials. In this work, carvone, an essential oil, was used to synthesize a bio-based polyol through a thiol-ene reaction. The chemical functions were analyzed through Fourier transformed infrared spectrum (FTIR), gel permeation chromatography (GPC), viscosity, and hydroxyl number, which confirmed the synthesis of carvone-based polyol. The latter was then physically blended with three different flame-retardants separately: expandable graphite (EG), aluminum trihydroxide (ATH), and aluminum hypophosphite (AHP). This facile method was demonstrated to be efficient as the inherently poor resistance to fire of polyurethane foams (PUF) was decreased due to the self-quenching fire properties. During the testing for the foams, it was observed that all three sets had a closed-cell content of around 95%, density in the range of 28-50 kg/m3, and average compressive strength of 210 kPa. Also, the flame retardancy presented a drastic decrease in the burning time and weight loss as the neat sample burned from 98 s and 40.7% and dropped to 11 s and 3.55 % (EG), 58 s, and 12.23 % (ATH), and 5.2 s and 3.6 % (AHP), respectively. Hence, an effective, and facile route to develop bio-based flame-retardant polyurethane is presented in this thesis, showing promising large-scale applications

Shotgun Mass Spectrometry Workflow Combining IEF and LC-MALDI-TOF/TOF

We present a high throughput shotgun mass spectrometry workflow using a bidimensional peptide fractionation procedure consisting of isoelectric focusing and RP-HPLC prior to mass spectrometric analysis, with the aim of optimizing peptide separation and protein identification. As part of the workflow we used the ‘Isotope-Coded Protein Labeling’ (ICPL) method for accurate relative quantitation of protein expression. Such workflow was successfully applied to a comparative proteome analysis of schizophrenia versus healthy control brain tissues and can be an alternative to proteome researches