The Symmetry Concept in the Perspective of Basic Education Teachers

The curricular changes that have occurred with the Portuguese Mathematics programme of study of 2007 showed, among other situations, the introduction of new contents and the new concept of symmetry. For the teachers, these changes require scientific updates to be provided so that the outcomes of the mathematics teaching can be guaranteed. In the academic year 2011/2012 a questionnaire was applied to a 142 inservice basic education teachers of a particular region of Portugal, to analyze the content knowledge in this subject (symmetry) and the form of scientific update occurred. The processing of data allowed us to identify inadequate conceptions, beliefs, topics more or less successful in responses and also compare the teacher’s responses of the different teaching groups.info:eu-repo/semantics/publishedVersio

Scalar field description of decaying-Λ\Lambda cosmologies

The conditions under which cosmologies driven by time varying cosmological terms can be described by a scalar field coupled to a perfect fluid are discussed. An algorithm to reconstruct potentials dynamically and thermodynamically analogue to given phenomenological $\Lambda$ models is presented. As a worked example, the deflationary cosmology, which evolves from a pure de Sitter vacuum state to a slightly modified FRW cosmology is considered. It is found that this is an example of nonsingular warm inflation with an asymptotic exponential potential. Differences with respect to other scalar field descriptions of decaying vacuum cosmologies are addressed and possible extensions are indicated.Comment: 12 pages, revtex, references added, corrected typos and minor text change

Transition Redshift: New Kinematic Constraints from Supernovae

The transition redshift (deceleration/acceleration) is discussed by expanding the deceleration parameter to first order around its present value. A detailed study is carried out by considering two different parameterizations: $q=q_0 + q_1z$ and $q=q_0 + q_1 z(1+z)^{-1}$, and the associated free parameters ($q_o, q_1$) are constrained by 3 different supernova samples. The previous analysis by Riess {\it{et al.}} [ApJ 607, 665, 2004] using the first expansion is slightly improved and confirmed in light of their recent data ({\emph{Gold}}07 sample). However, by fitting the model with the Supernova Legacy Survey (SNLS) type Ia sample we find that the best fit to the redshift transition is $z_t = 0.61$ instead of $z_t = 0.46$ as derived by the High-z Supernovae Search (HZSNS) team. This result based in the SNLS sample is also in good agreement with the Davis {\it{et al.}} sample, $z_t=0.60^{+0.28}_{-0.11}$ ($1\sigma$). Such results are in line with some independent analyzes and accommodates more easily the concordance flat model ($\Lambda$CDM). For both parameterizations, the three SNe type Ia samples considered favor recent acceleration and past deceleration with a high degree of statistical confidence level. All the kinematic results presented here depend neither on the validity of general relativity nor the matter-energy contents of the Universe.Comment: 19 pages, 15 figures, 1 table, revised version accepted for publication in MNRA

The management of student´s virtual money – sensibilisation and learning for life

The advanced technological age, marketing and society of the abundance in which we live, have a strong influence on the consumption and eating habits of the children. Every day in schools, these little human beings make autonomous choices and their parents, despite seeking to control and know their actions, cannot do it entirely for many reasons. The study was carried out in a group of the fifth grade and their results were subjected to a descriptive and inferential analysis, in which the purpose was to study the relation of some of the variables in question. The conclusions point for example to the parents' lack of knowledge in what concerns the type of consumption and on how their students spend their money. So it can be said that the role of the school in raising responsible citizens in managing their money is a necessary and continuous learning throughout the school life.info:eu-repo/semantics/publishedVersio

Large-scale analysis of the SDSS-III DR8 photometric luminous galaxies angular correlation function

We analyse the large-scale angular correlation function (ACF) of the CMASS luminous galaxies (LGs), a photometric-redshift catalogue based on the Data Release 8 (DR8) of the Sloan Digital Sky Survey-III. This catalogue contains over $600 \, \, 000$ LGs in the range $0.45 \leq z \leq 0.65$, which was split into four redshift shells of constant width. First, we estimate the constraints on the redshift-space distortion (RSD) parameters $b\sigma_8$ and $f\sigma_8$, where $b$ is the galaxy bias, $f$ the growth rate and $\sigma_8$ is the normalization of the perturbations, finding that they vary appreciably among different redshift shells, in agreement with previous results using DR7 data. When assuming constant RSD parameters over the survey redshift range, we obtain $f\sigma_8 = 0.69 \pm 0.21$, which agrees at the $1.5\sigma$ level with Baryon Oscillation Spectroscopic Survey DR9 spectroscopic results. Next, we performed two cosmological analyses, where relevant parameters not fitted were kept fixed at their fiducial values. In the first analysis, we extracted the baryon acoustic oscillation peak position for the four redshift shells, and combined with the sound horizon scale from 7-year \textit{Wilkinson Microwave Anisotropy Probe} $(WMAP7)$ to produce the constraints $\Omega_{m}=0.249 \pm 0.031$ and $w=-0.885 \pm 0.145$. In the second analysis, we used the ACF full shape information to constrain cosmology using real data for the first time, finding $\Omega_{m} = 0.280 \pm 0.022$ and $f_b = \Omega_b/\Omega_m = 0.211 \pm 0.026$. These results are in good agreement with $WMAP7$ findings, showing that the ACF can be efficiently applied to constrain cosmology in future photometric galaxy surveys.Comment: MNRAS accepted. Minor corrections to match publish versio

Processo agroindustrial: obtenção de melão desidratado por associação de osmose e secagem em estufa.

O presente trabalho descreve um processo de obtencao de melao desidratado por osmose seguida de secagem em estufa, como uma forma alternativa de aproveitamento e agregacao de valor ao produto.bitstream/CNPAT-2010/8613/1/Ct-095.pd

Influência da cobertura morta no desenvolvimento de fruteiras tropicais.

bitstream/CNPAT-2010/7344/1/Dc-049.pd