Estudo da influência da presença das estações de metrô sobre estrutura espacial urbana

Este artigo apresenta pesquisa que busca compreender de que maneira a implantação de uma estação de metrô em ambiente urbano consolidado altera as dinâmicas socioespaciais de seu entorno. O estudo pretende, a partir da análise espaço temporal e de dados sociogeográficos compreender a transformação da estrutura espacial urbana que possam ser associados a presença da estação. A cidade é uma estrutura dinâmica, um sistema complexo de redes de relações físicas e sociais onde a intervenção sobre o ambiente construído causa interferências sobre todo o sistema. A pesquisa parte do principio de que uma estação de transporte de massa redefine os níveis de acessibilidade de um local em sua relação com sistema urbano, enquanto interfere na estrutura socioespacial de seu entorno. A relação entre transporte como elemento reestruturador e forma urbana é analisada a partir de mudanças relativas a população, usos do solo e acessibilidade. O crescimento do número de redes de metrô, aliado à crescente necessidade de mobilidade urbana justifica a necessidade de aprofundamento na análise de seus impactos sobre a estrutura urbana. Esta pesquisa de mestrado se encontra em de desenvolvimento, por iniciar o estudo empírico, cujos resultados serão apresentados oportunamente. A maior limitação encontrada até o momento é a disponibilidade de dados na escala necessária e em etapa anterior e posterior a implantação da estação que permita a análise proposta.This article presents a research that seeks to understand how the implementation of a subway station in consolidated urban environment changes the dynamics sócioespaciais of its surroundings. The study intends through spatial analysis and sociogeographical data to understand the transformation of urban space structure that may be associated with the presence of the station. The city is a dynamic structure, a complex system as a network of physical and social relations, where interventions on the built environment will interfere on the whole system. The research starts from the principle that while a transit station resets the accessibility of a site in its relation with the urban system, it also interferes with the socio-spatial structure of its surroundings. The relationship between transport as restructuring element and urban form is assed through changes concerning population, landuse and accessibility. The growing number of metro networks, together with the increasing need for urban mobility, justifies the need to deepen the analysis of their impacts on the urban structure. This research as a master's degree is under development, and about to initiate the empirical study, and its results shall be presented in due course. The highest limitation found so far is the availability of data at the required scale and time (before and after the station) allowing the proposed analysis

Search for an infrared counterpart of IGR J16358-4756

We report here on near infrared observations of the field around IGR J16358-4756. The source belongs to the new class of highly absorbed X-ray binaries discovered by IBIS/INTEGRAL. Our primary goal was to identify the infrared counterpart of the source, previously suggested to be a LMXB and then further reclassified as a HMXB. We have made use of Chandra observations of the source in order to better constrain the number of possible counterparts. Using the differential photometry technique, in observations spanning a timescale of 1 month, we found no long term variability in our observations. This is compatible, and we suggest here, that the source is a HMXB.Comment: 5 pages, 2 figures, all styles included; to be published in: "The Transient Milky Way: a perspective for MIRAX", eds. F. D'Amico, J. Braga, and R. E. Rothschild, AIP Conference Proceeding

Constructing Coincident and Leading Indices of Economic Activity for the Brazilian Economy

This paper has three original contributions. The first is the reconstructioneffort of the series of employment and income to allow the creation of a newcoincident index for the Brazilian economic activity. The second is the con-struction of a coincident index of the economic activity for Brazil, and fromit, (re) establish a chronology of recessions in the recent past of the Brazilianeconomy. The coincident index follows the methodology proposed by TCBand it covers the period 1980:1 to 2007:11. The third is the construction andevaluation of many leading indicators of economic activity for Brazil which fillsan important gap in the Brazilian Business Cycles literature.

Correlating the interstellar magnetic field with protostellar jets and its sources

This article combines new CCD polarimetric data with previous information about protostellar objects in a search for correlations involving the interstellar magnetic field. Specifically, we carried out an optical polarimetric study of a sample of 28 fields of 10 X 10 arcmin^2 located in the neighborhood of protostellar jets and randomly spread over the Galaxy. The polarimetry of a large number of field stars is used to estimate both the average and dispersion of the interstellar magnetic field (ISMF) direction in each region. The results of the applied statistical tests are as follows. Concerning the alignment between the jet direction and the interstellar magnetic field, the whole sample does not show alignment. There is, however, a statistically significant alignment for objects of Classes 0 and I. Regarding the interstellar magnetic field dispersion, our sample presents values slightly larger for regions containing T Tauri objects than for those harboring younger protostars. Moreover the ISMF dispersion in regions containing high-mass objects tends to be larger than in those including only low-mass protostars. In our sample, the mean interstellar polarization as a function of the average interstellar extinction in a region reaches a maximum value around 3% for A(V) = 5, after which it decreases. Our data also show a clear correlation of the mean value of the interstellar polarization with the dispersion of the interstellar magnetic field: the larger the dispersion, the smaller the polarization. Based on a comparison of our and previous results, we suggest that the dispersion in regions forming stars is larger than in quiescent regions.Comment: ApJ accepte

All-electron full-potential implementation of real-time TDDFT in exciting

Linearized augmented planewaves combined with local-orbitals (LAPW+lo) are arguably the most precise basis set to represent Kohn-Sham states. When employed within real-time time-dependent density functional theory (RT-TDDFT), they promise ultimate precision achievable for exploring the evolution of electronic excitations. In this work, we present an implementation of RT-TDDFT in the full-potential LAPW+lo code exciting. We benchmark our results against those obtained by linear-response TDDFT with exciting and by RT-TDDFT calculations with the Octopus code, finding a satisfactory level of agreement. To illustrate possible applications of our implementation, we have chosen three examples: the dynamic behavior of excitations in MoS$_2$ induced by a laser pulse, the third harmonic generation in silicon, and a pump-probe experiment in diamond

Observing Grasping Actions Directed to Emotion-Laden Objects: Effects upon Corticospinal Excitability

The motor system is recruited whenever one executes an action as well as when one observes the same action being executed by others. Although it is well established that emotion modulates the motor system, the effect of observing other individuals acting in an emotional context is particularly elusive. The main aim of this study was to investigate the effect induced by the observation of grasping directed to emotion-laden objects upon corticospinal excitability (CSE). Participants classified video-clips depicting the right-hand of an actor grasping emotion-laden objects. Twenty video-clips differing in terms of valence but balanced in arousal level were selected. Motor evoked potentials (MEPs) were then recorded from the first dorsal interosseous using transcranial magnetic stimulation (TMS) while the participants observed the selected emotional video-clips. During the video-clip presentation, TMS pulses were randomly applied at one of two different time points of grasping: (1) maximum grip aperture, and (2) object contact time. CSE was higher during the observation of grasping directed to unpleasant objects compared to pleasant ones. These results indicate that when someone observes an action of grasping directed to emotion-laden objects, the effect of the object valence promotes a specific modulation over the motor system.Fil: Nogueira Campos, Anaelli A.. Universidade Federal de Juiz de Fora; BrasilFil: Saunier, Ghislain. Universidade Federal do Pará; BrasilFil: Della Maggiore, Valeria Monica. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Fisiología y Biofísica Bernardo Houssay. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Fisiología y Biofísica Bernardo Houssay; ArgentinaFil: De Oliveira, Laura A. S.. Centro Universitário Augusto Motta; BrasilFil: Rodrigues, Erika C.. Centro Universitário Augusto Motta; BrasilFil: Vargas, Claudia D.. Universidade Federal do Rio de Janeiro; Brasi

Evidence for reduced magnetic braking in polars from binary population models

We present the first population synthesis of synchronous magnetic cataclysmic variables, called polars, taking into account the effect of the white dwarf (WD) magnetic field on angular momentum loss. We implemented the reduced magnetic braking (MB) model proposed by Li, Wu & Wickramasinghe into the Binary Stellar Evolution (BSE) code recently calibrated for cataclysmic variable (CV) evolution. We then compared separately our predictions for polars and non-magnetic CVs with a large and homogeneous sample of observed CVs from the Sloan Digital Sky Survey. We found that the predicted orbital period distributions and space densities agree with the observations if period bouncers are excluded. For polars, we also find agreement between predicted and observed mass transfer rates, while the mass transfer rates of non-magnetic CVs with periods ≳3 h drastically disagree with those derived from observations. Our results provide strong evidence that the reduced MB model for the evolution of highly magnetized accreting WDs can explain the observed properties of polars. The remaining main issues in our understanding of CV evolution are the origin of the large number of highly magnetic WDs, the large scatter of the observed mass transfer rates for non-magnetic systems with periods ≳3 h, and the absence of period bouncers in observed samples

Essays in entrepreneurship among foreign individuals

We study how countries of origin affect foreign individuals’ choice between salaried work and entrepreneurship upon arrival to the host country. Using a change in the Portuguese immigration law we evaluate the impact of reducing regulations on entrepreneurship upon the probability of foreign individuals choose entrepreneurship upon arrival. We find that foreigners from countries more dissimilar to the host country and those from wealthier countries are more likely engage in entrepreneurship upon arrival than those from similar countries. Foreigners from countries outside the European Economic Area, who have to fulfil requirements that are not required to those from countries within this area, are less likely to enter the labor market as entrepreneurs than those from countries within this area. According to our findings reducing legal requirements to foreign entrepreneurship may encourage foreigners to engage in entrepreneurship upon arrival, although such impact is not considerable