Expectativas dos estudantes quanto a sua formação na Universidade Federal da Integração Latino Americana

Anais do II Encontro de Iniciação Científica e de Extensão da Unila - Sessão de Antropologia - 03/07/13 – 13h30 às 18h30 - Unila-PTI - Bloco 09 – Espaço 03 – Sala 02A coopera ̧c ̃ao, o intercˆambio e a integra ̧c ̃ ao s ̃ao os pilares conceituais do projeto pedag ́ogico e pol ́ ıtico da Universidade Federal da Integra ̧c ̃ao Latino Americana (UNILA), localizada em Foz do Igua ̧cu-Paran ́a. Com isto, a institui ̧c ̃ao busca que estudantes de diferentes nacionalidades adquiram uma vis ̃ao multicultural e complexa da realidade latino-americana. A UNILA como um espa ̧co de educa ̧c ̃ao internacional enfrenta desafios de adapta ̧c ̃ao e integra ̧c ̃ao pr ́oprios de uma institui ̧c ̃ao em que a metade de seus estudantes s ̃ao estrangeiros e, onde a diversidade ́etnica e lingu ́ ıstica est ̃ao presentes. Esse estudo busca caracterizar os motivos que orientam a escolha dos estudantes ao estudar na UNILA, levando em conta suas espectativas ao entrar na institui ̧c ̃ao e, como ou com quem os estudantes se relacionam, ou de que maneira constroem suas redes sociais e acadˆemicas e por que. O estudo parte da seguinte pergunta: Como os es- tudantes se interrelacionam em sala de aula? Para saber como os estudantes constroem suas redes sociais, acadˆemicas e por que. A hip ́otese ́e que cursos mais heterogˆeneos sejam ambientes com mais possibilidades de integra ̧c ̃ao, e as intera ̧c ̃oes sociais constru ́ ıdas em sala de aula sejam diversificadas. Essa quest ̃ao ́e importante j ́ a que a analise foca nas rela ̧c ̃oes entre os estudantes de um curso espec ́ ıfico, o que nos permitir ́a descobrir se existem padr ̃oes se formando entre o grupo. Essa pergunta investiga como eles se relacionam na hora de apresentar seus trabalhos ou construir seus grupos de estudos. Dentro disso, procura-se identificar quais seriam as categorias ou vari ́aveis que influenciariam nas decis ̃oes desses atores, ou seja, se por gˆenero, idioma, naci- onalidade, etnia ou origem geogr ́a fica. Tomando como foco a quest ̃ ao da multiculturalidade, ́e necess ́ ario intender quais as expectativas dos estudantes quanto a sua forma ̧c ̃ ao na universidade e como definem suas experiˆencias acadˆemicas, para assim, compreender como est ́a se dando o processo de integra ̧c ̃ao desde um ponto de vista focado no aluno e nas rela ̧c ̃oes sociais cons- tru ́ ıdas, para saber, como esses fatores contribuem no processo de constru ̧c ̃ ao e reconstru ̧c ̃ ao de suas identidades individuais e coletivas. Esse trabalho ́e fruto de um estudo interdisciplinar que integra dados obtidos atrav ́es de um question ́ario estruturado, aplicado a uma amostra represen- tativa de estudantes escolhidos aleatoriamente, de entrevistas etnogr ́ a ficas feitas com estudantes de diferentes nacionalidades e uma Analises de Redes Sociais (ARS) aplicadas a uma turma fechada. A partir dos dados coletados, procuramos conhecer os aspectos que influenciam os estudantes a estudarem na UNILA e, como est ̃ao se dando a conforma ̧c ̃ao das redes de intera ̧c ̃ ao social dos estudantes em sala de aula. O objetivo ́e saber como os estudantes definem suas experiˆencias acadˆemicas, e tamb ́em que grau de intera ̧c ̃ ao est ́ a se criando a partir das rela ̧c ̃ oes sociais e culturais diversas obtidas a partir da analise formal das redes sociais dos estudantes de um dos cursos de bacharelado da universidade, o que permite observar alguns padr ̃oes que podem estar se formando nesses grupos. O estudo da ARS foi feito com a turma de Desenvolvi- mento Rural e Seguran ̧ca Alimentar, 3 a semestre. Essa turma foi escolhida por ser uma turma heterogˆenea onde se encontram cinco nacionalidades das onze que fazem parte atualmente da UNILA. Os entrevistados responderam a quatro perguntas com as quais foram geradas quatro redes. Com base nas redes, podemos observar que as rela ̧c ̃oes podem estar sendo geradas por afinidades lingu ́ ısticas e tamb ́em regionais. Foi poss ́ ıvel visualizar dois grupos, sendo o primeiro composto por indiv ́ ıduos de nacionalidade brasileiros e paraguaios, enquanto que o segundo ́e composto majoritariamente por peruanos, bolivianos e venezuelanos. Essas rela ̧c ̃oes podem es- tar ocorrendo por uma quest ̃ao lingu ́ ıstica, sendo que, brasileiros se relacionam mais entre si, mas tamb ́em com alguns paraguaios, isso nos leva a pensar que a posi ̧c ̃ao geogr ́a fica entre os pa ́ ıses pode ser um fator que tende a aproximar esses indiv ́ ıduos, a l ́ ıngua aqui nem sempre seria um empecilho para as rela ̧c ̃oes sociais. J ́a no caso dos indiv ́ ıduos oriundos dos pa ́ ıses andinos, ocorre que estes tendem a se relacionar mais com espano-falantes por terem maior dificuldade com o idioma portuguˆes, por conta de um menor contato entre suas popula ̧c ̃ oes. Com base nessa an ́alise a hip ́otese n ̃ ao ́e v ́alida, pois as rela ̧c ̃ oes tendem a ser pouco diversas seguindo padr ̃oes de homogeneidade em ambientes que apresentam maior diversidade.Universidade Federal da Integração Latino-Americana (UNILA

Cosmology and Cluster Halo Scaling Relations

We explore the effects of dark matter and dark energy on the dynamical scaling properties of galaxy clusters. We investigate the cluster Faber-Jackson (FJ), Kormendy and Fundamental Plane (FP) relations between the mass, radius and velocity dispersion of cluster size halos in cosmological $N$-body simulations. The simulations span a wide range of cosmological parameters, representing open, flat and closed Universes. Independently of the cosmology, we find that the simulated clusters are close to a perfect virial state and do indeed define a Fundamental Plane. The fitted parameters of the FJ, Kormendy and FP relationships do not show any significant dependence on $\Omega_m$ and/or $\Omega_{\Lambda}$. The one outstanding effect is the influence of $\Omega_{m}$ on the thickness of the Fundamental Plane. Following the time evolution of our models, we find slight changes of FJ and Kormendy parameters in high $\Omega_m$ universe, along with a slight decrease of FP fitting parameters. We also see an initial increase of the FP thickness followed by a convergence to a nearly constant value. The epoch of convergence is later for higher values of $\Omega_m$ while the thickness remains constant in the low $\Omega_m$ $\Lambda$-models. We also find a continuous increase of the FP thickness in the Standard CDM (SCDM) cosmology. There is no evidence that these differences are due to the different power spectrum slope at cluster scales. From the point of view of the FP, there is little difference between clusters that quietly accreted their mass and those that underwent massive mergers. The principal effect of strong mergers is to change significantly the ratio of the half-mass radius $r_{half}$ to the harmonic mean radius $r_h$.Comment: 24 pages, 17 figures, submitted to MNRA

z~2: An Epoch of Disk Assembly

We explore the evolution of the internal gas kinematics of star-forming galaxies from the peak of cosmic star-formation at $z\sim2$ to today. Measurements of galaxy rotation velocity $V_{rot}$, which quantify ordered motions, and gas velocity dispersion $\sigma_g$, which quantify disordered motions, are adopted from the DEEP2 and SIGMA surveys. This sample covers a continuous baseline in redshift from $z=2.5$ to $z=0.1$, spanning 10 Gyrs. At low redshift, nearly all sufficiently massive star-forming galaxies are rotationally supported ($V_{rot}>\sigma_g$). By $z=2$, the percentage of galaxies with rotational support has declined to 50$\%$ at low stellar mass ($10^{9}-10^{10}\,M_{\odot}$) and 70$\%$ at high stellar mass ($10^{10}-10^{11}M_{\odot}$). For $V_{rot}\,>\,3\,\sigma_g$, the percentage drops below 35$\%$ for all masses. From $z\,=\,2$ to now, galaxies exhibit remarkably smooth kinematic evolution on average. All galaxies tend towards rotational support with time, and it is reached earlier in higher mass systems. This is mostly due to an average decline in $\sigma_g$ by a factor of 3 since a redshift of 2, which is independent of mass. Over the same time period, $V_{rot}$ increases by a factor of 1.5 for low mass systems, but does not evolve for high mass systems. These trends in $V_{rot}$ and $\sigma_g$ with time are at a fixed stellar mass and should not be interpreted as evolutionary tracks for galaxy populations. When galaxy populations are linked in time with abundance matching, not only does $\sigma_g$ decline with time as before, but $V_{rot}$ strongly increases with time for all galaxy masses. This enhances the evolution in $V_{rot}/\sigma_g$. These results indicate that $z\,=\,2$ is a period of disk assembly, during which the strong rotational support present in today's massive disk galaxies is only just beginning to emerge.Comment: 12 pages, 8 figures, submitted to Ap

The Origin of Color Gradients in Early-Type Systems and Their Compactness at High-z

In this Letter, we present mean optical+NIR color gradient estimates for 5080 early-type galaxies (ETGs) in the grizYJHK wavebands of the Sloan Digital Sky Survey (SDSS) plus UKIRT Infrared Deep Sky Survey (UKIDSS). The color gradient is estimated as the logarithmic slope of the radial color profile in ETGs. With such a large sample size, we study the variation of the mean color gradient as a function of waveband with unprecedented accuracy. We find that (i) color gradients are mainly due, on average, to a metallicity variation of about -0.4dex per decade in galaxy radius; and (ii) a small, but significant, positive age gradient is present, on average, in ETGs, with the inner stellar population being slightly younger, by ~0.1dex per radial decade, than the outer one. Also, we show that the presence of a positive mean age gradient in ETGs, as found in the present study, implies their effective radius to be smaller at high z, consistent with observations.Comment: 4 pages, 2 color figures, accepted for publication in the Astrophysical Journal Letter

Systematic variation of the stellar Initial Mass Function with velocity dispersion in early-type galaxies

An essential component of galaxy formation theory is the stellar initial mass function (IMF), that describes the parent distribution of stellar mass in star forming regions. We present observational evidence in a sample of early-type galaxies (ETGs) of a tight correlation between central velocity dispersion and the strength of several absorption features sensitive to the presence of low-mass stars. Our sample comprises ~40,000 ETGs from the SPIDER survey (z<0.1). The data, extracted from the Sloan Digital Sky Survey, are combined, rejecting both noisy data, and spectra with contamination from telluric lines, resulting in a set of 18 stacked spectra at high signal-to-noise ratio (S/N> 400 per A). A combined analysis of IMF-sensitive line strengths and spectral fitting is performed with the latest state-of the art population synthesis models (an extended version of the MILES models). A significant trend is found between IMF slope and velocity dispersion, towards an excess of low-mass stars in the most massive galaxies. Although we emphasize that accurate values of the IMF slope will require a detailed analysis of chemical composition (such as [a/Fe] or even individual element abundance ratios), the observed trends suggest that low-mass ETGs are better fit by a Kroupa-like IMF, whereas massive galaxies require bottom-heavy IMFs, exceeding the Salpeter slope at velocity dispersions above 200km/s.Comment: 5 pages, 4 figures, accepted for publication in MNRAS Letter

The Faber-Jackson relation for early-type galaxies: Dependence on the magnitude range

We take a sample of early-type galaxies from the Sloan Digital Sky Survey (SDSS-DR7, $\sim$ 90 000 galaxies) spanning a range of approximately 7 $mag$ in both $g$ and $r$ filters and analyse the behaviour of the Faber-Jackson relation parameters as functions of the magnitude range. We calculate the parameters in two ways: i) We consider the faintest (brightest) galaxies in each sample and we progressively increase the width of the magnitude interval by inclusion of the brighter (fainter) galaxies (increasing-magnitude-intervals), and ii) we consider narrow-magnitude intervals of the same width ($\Delta M = 1.0$ $mag$) over the whole magnitude range available (narrow-magnitude-intervals). Our main results are that: i) in both increasing and narrow-magnitude-intervals the Faber-Jackson relation parameters change systematically, ii) non-parametric tests show that the fluctuations in the values of the slope of the Faber-Jackson relation are not products of chance variations. We conclude that the values of the Faber-Jackson relation parameters depend on the width of the magnitude range and the luminosity of galaxies within the magnitude range. This dependence is caused, to a great extent by the selection effects and because the geometrical shape of the distribution of galaxies on the $M - \log (\sigma_{0})$ plane depends on luminosity. We therefore emphasize that if the luminosity of galaxies or the width of the magnitude range or both are not taken into consideration when comparing the structural relations of galaxy samples for different wavelengths, environments, redshifts and luminosities, any differences found may be misinterpreted.Comment: 15 pages, 5 figures. A&A. Accepte

The age-redshift relation for Luminous Red Galaxies in the Sloan Digital Sky Survey

We present a detailed analysis of 17,852 quiescent, Luminous Red Galaxies (LRGs) selected from Sloan Digital Sky Survey (SDSS) Data Release Seven (DR7) spanning a redshift range of 0.0 < z < 0.4. These galaxies are co-added into four equal bins of velocity dispersion and luminosity to produce high signal-to-noise spectra (>100A^{-1}), thus facilitating accurate measurements of the standard Lick absorption-line indices. In particular, we have carefully corrected and calibrated these indices onto the commonly used Lick/IDS system, thus allowing us to compare these data with other measurements in the literature, and derive realistic ages, metallicities ([Z/H]) and alpha-element abundance ratios ([alpha/Fe]) for these galaxies using Simple Stellar Population (SSP) models. We use these data to study the relationship of these galaxy parameters with redshift, and find little evidence for evolution in metallicity or alpha-elements (especially for our intermediate mass samples). This demonstrates that our subsamples are consistent with pure passive evolving (i.e. no chemical evolution) and represent a homogeneous population over this redshift range. We also present the age-redshift relation for these LRGs and clearly see a decrease in their age with redshift (5 Gyrs over the redshift range studied here) which is fully consistent with the cosmological lookback times in a concordance Lambda CDM universe. We also see that our most massive sample of LRGs is the youngest compared to the lower mass galaxies. We provide these data now to help future cosmological and galaxy evolution studies of LRGs, and provide in the appendices of this paper the required methodology and information to calibrate SDSS spectra onto the Lick/IDS system.Comment: 26 pages, with several appendices containing data. Accepted for publication in MNRA

The Formation and Evolution of Virgo Cluster Galaxies - I. Broadband Optical & Infrared Colours

We use a combination of deep optical (gri) and near-infrared (H) photometry to study the radially-resolved colours of a broad sample of 300 Virgo cluster galaxies. For most galaxy types, we find that the median g-H colour gradient is either flat (gas-poor giants and gas-rich dwarfs) or negative (i.e., colours become bluer with increasing radius; gas-poor dwarfs, spirals, and gas-poor peculiars). Later-type galaxies typically exhibit more negative gradients than early-types. Given the lack of a correlation between the central colours and axis ratios of Virgo spiral galaxies, we argue that dust likely plays a small role, if at all, in setting those colour gradients. We search for possible correlations between galaxy colour and photometric structure or environment and find that the Virgo galaxy colours become redder with increasing concentration, luminosity and surface brightness, while no dependence with cluster-centric radius or local galaxy density is detected (over a range of ~2 Mpc and ~3-16 Mpc^-2, respectively). However, the colours of gas-rich Virgo galaxies do correlate with neutral gas deficiency, such that these galaxies become redder with higher deficiencies. Comparisons with stellar population models suggest that these colour gradients arise principally from variations in stellar metallicity within these galaxies, while age variations only make a significant contribution to the colour gradients of Virgo irregulars. A detailed stellar population analysis based on this material is presented in Roediger et al (2011b; arXiv:1011.3511).Comment: 34 pages, 12 figures, 1 table, submitted to MNRAS; Paper II (arXiv:1011.3511) has also been update

The mRNA expression of SETD2 in human breast cancer: Correlation with clinico-athological parameters

BACKGROUND: SET domain containing protein 2 (SETD2) is a histone methyltransferase that is involved in transcriptional elongation. There is evidence that SETD2 interacts with p53 and selectively regulates its downstream genes. Therefore, it could be implicated in the process of carcinogenesis. Furthermore, this gene is located on the short arm of chromosome 3p and we previously demonstrated that the 3p21.31 region of chromosome 3 was associated with permanent growth arrest of breast cancer cells. This region includes closely related genes namely: MYL3, CCDC12, KIF9, KLHL18 and SETD2. Based on the biological function of these genes, SETD2 is the most likely gene to play a tumour suppressor role and explain our previous findings. Our objective was to determine, using quantitative PCR, whether the mRNA expression levels of SETD2 were consistent with a tumour suppressive function in breast cancer. This is the first study in the literature to examine the direct relationship between SETD2 and breast cancer. METHODS: A total of 153 samples were analysed. The levels of transcription of SETD2 were determined using quantitative PCR and normalized against (CK19). Transcript levels within breast cancer specimens were compared to normal background tissues and analyzed against conventional pathological parameters and clinical outcome over a 10 year follow-up period. RESULTS: The levels of SETD2 mRNA were significantly lower in malignant samples (p = 0.0345) and decreased with increasing tumour stage. SETD2 expression levels were significantly lower in samples from patients who developed metastasis, local recurrence, or died of breast cancer when compared to those who were disease free for > 10 years (p = 0.041). CONCLUSION: This study demonstrates a compelling trend for SETD2 transcription levels to be lower in cancerous tissues and in patients who developed progressive disease. These findings are consistent with a possible tumour suppressor function of this gene in breast cancer