Personal Meaning Maps as an Assessment Tool for a Planetarium Session: A Study with Primary School Children

This study aims to analyse the potentialities of using Personal Meaning Maps to assess school children’s learning in a visit to a Planetarium. A total of 123 primary students were involved. They were asked to create a PMM, and a drawing, before and after the visit. The results suggest that the visit enhanced the degree to which students generate words and conceptual categories to describe their understanding of the suggested concepts. PMMs seemed to be a good tool to evaluate the impact of the activities on students’ ideas about the thematic explored. Drawings helped to understand the main misconceptions.info:eu-repo/semantics/publishedVersio

Relativistic treatment of harmonics from impurity systems in quantum wires

Within a one particle approximation of the Dirac equation we investigate a defect system in a quantum wire. We demonstrate that by minimally coupling a laser field of frequency omega to such an impurity system, one may generate harmonics of multiples of the driving frequency. In a multiple defect system one may employ the distance between the defects in order to tune the cut-off frequency.Comment: 9 pages Latex, 8 eps figures, section added, numerics improve

Promoting science outdoor activities for elementary school children: Contributions from a research laboratory

The purposes of the study were to analyse the promotion of scientific literacy through practical research activities and to identify children's conceptions about scientists and how they do science. Elementary school children were engaged in two scientific experiments in a marine biology research laboratory. A total of 136 students answered a questionnaire about their previous habits towards science and carried out the following actions: (1) a guided visit to the laboratory, (2) a brief presentation of the research theme, (3) the development of two experiments, and (4) a questionnaire about the experiments and science conceptions. The research methods included observation, document analysis, and content analysis of the answers to the questionnaires. Additionally, each visit was video recorded in order to design learning materials. The results revealed that most of the pupils were able to follow every stage of experimentation. However, some of them misinterpreted results and conclusions. One implication of the study is that this type of outdoor activity is extremely important to promote meaningful science learning in children, but more care should be taken in practical science activities so that children can overcome some common difficulties when performing scientific inquiry.info:eu-repo/semantics/publishedVersio

History of science and science museums: an enriching partnership for elementary school science

The activity presented in this article is intended for elementary school students and focus on the pioneering oceanographic work of the Portuguese King Carlos I. This activity involves the exploration of the exhibits belonging to two different science museums, the Aquarium Vasco da Gama and the Maritime Museum. Students were asked to study fish adaptations to deep sea, through the exploration of a fictional story, also based on historical data from the work of the King that served as a guiding script for all the subsequent tasks. In both museums, students had access to observations of: historical collections of organisms, oceanographic biological sampling instruments, fish gears and ships. They could also observe the characteristics and adaptations of diverse deep-sea fish species. The present study aimed to analyse the impact of this activity on students’ scientific knowledge, on their understanding of the nature of science and on the development of transversal skills. All students considered the project very interesting. The obtained results suggest that the activity promoted not only the understanding of scientific concepts, but also the development of knowledge about science itself and the construction of scientific knowledge. This emphasizes the relevance of creating activities informed by the history of science. As a final remark we suggest that the partnership between elementary schools and museums should be seen as an educational project approach, in which the teacher has to assume a key, mediating role between the school and the museums.info:eu-repo/semantics/publishedVersio

Noise Sources in Photometry and Radial Velocities

The quest for Earth-like, extrasolar planets (exoplanets), especially those located inside the habitable zone of their host stars, requires techniques sensitive enough to detect the faint signals produced by those planets. The radial velocity (RV) and photometric transit methods are the most widely used and also the most efficient methods for detecting and characterizing exoplanets. However, presence of astrophysical "noise" makes it difficult to detect and accurately characterize exoplanets. It is important to note that the amplitude of such astrophysical noise is larger than both the signal of Earth-like exoplanets and state-of-the-art instrumentation limit precision, making this a pressing topic that needs to be addressed. In this chapter, I present a general review of the main sources of noise in photometric and RV observations, namely, stellar oscillations, granulation, and magnetic activity. Moreover, for each noise source I discuss the techniques and observational strategies which allow us to mitigate their impact.Comment: 11 pages, 2 tables, Lecture presented at the IVth Azores International Advanced School in Space Sciences on "Asteroseismology and Exoplanets: Listening to the Stars and Searching for New Worlds" (arXiv:1709.00645), which took place in Horta, Azores Islands, Portugal in July 201

Pegamento De Enxertos De Tomateiro Em Diferentes Solanáceas

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)This paper aimed to assess tomato grafting on different solanaceous species through two grafting methods. Scions were cut from cultivar Santa Cruz Kada seedlings. A fully randomized experimental design was carried out with treatments in a 9 x 2 factorial scheme. As rootstocks, four accessions of mini-tomatoes (0224-53, RVTC 57, RVTC 20 and 6889-50 Solanum lycopersicum L); two species of wild tomato (Solanum habrochaites var hirsutum ‘PI-127826’ and Solanum pennellii ‘LA716’); other two tomato species [Solanum, cocona (Solanum sessiliflorum) and physalis (Physalis peruviana)] and a control with cultivar Santa Cruz Kada (auto-graft) rootstocks were used. In addition, two grafting methods were evaluated full cleft and approach graft. Fifteen days after grafting, plants were assessed for graft-take percentage; root length; plant height; leaf number; foliar area; root, stem and leaf dry matter; and ratio between shoot and root dry matter. Based on the results, we may state rootstock and grafting interaction had effect on both graft-take rate and plant development. Overall, the studied plants should be recommended as rootstock, except for 6889-50 mini-tomato (S. lycopersicum L.) and S. pennellii. Full cleft grafting was most suitable for cocona and physalis, while the approach method showed better results for the mini-tomato accessions 0224-53, RVTC 57 and RVTC 20, as well as for S. habrochaites. © 2016, Universidade Federal Rural do Semi-Arid. All rights reserved.302513520CAPES, Coordenação de Aperfeiçoamento de Pessoal de Nível SuperiorCoordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES

Seleção De Genótipos De Tomateiro Para Processamento Com Alto Teor De Zingibereno Resistentes A Pragas

Tomato cultivars resistant to arthropod pests are an important tool to reduce the use of pesticides. Resistance sources can be found in wild Solanum species such as S. habrochaites, which shows high levels of zingiberene (ZGB). This study aimed to evaluate the resistance of a tomato F2 progeny to spider mite and whitefly by evaluating the ZGB content, in laboratory, in plants from the F2 population of the interspecific crossing Solanum lycopersicum cultivar Redenção x Solanum habrochaites var. hirsutum (PI-127826), F1 plants, susceptible plants (cultivar Redenção) and plants of the wild species (PI-127826). From the F2 population, six plants with high content and three with low content of ZGB were selected. For evaluating the impact of ZGB on the spider mite behavior, the distance walked by spider mites from a central point was measured on the selected plants and their parents. For whitefly, the number of eggs and nymphs were quantified. Spider mites travelled shorter distances in plants with high ZGB content. Also, the number of whitefly eggs and nymphs was lower in these plants. Higher ZBG contents affected negatively both the spider mite and the whitefly behavior. © 2016, Sociedade de Olericultura do Brasil. All rights reserved.34338739

Measurement of D*+/- meson production in jets from pp collisions at sqrt(s) = 7 TeV with the ATLAS detector

This paper reports a measurement of D*+/- meson production in jets from proton-proton collisions at a center-of-mass energy of sqrt(s) = 7 TeV at the CERN Large Hadron Collider. The measurement is based on a data sample recorded with the ATLAS detector with an integrated luminosity of 0.30 pb^-1 for jets with transverse momentum between 25 and 70 GeV in the pseudorapidity range |eta| < 2.5. D*+/- mesons found in jets are fully reconstructed in the decay chain: D*+ -> D0pi+, D0 -> K-pi+, and its charge conjugate. The production rate is found to be N(D*+/-)/N(jet) = 0.025 +/- 0.001(stat.) +/- 0.004(syst.) for D*+/- mesons that carry a fraction z of the jet momentum in the range 0.3 < z < 1. Monte Carlo predictions fail to describe the data at small values of z, and this is most marked at low jet transverse momentum.Comment: 10 pages plus author list (22 pages total), 5 figures, 1 table, matches published version in Physical Review

Search for supersymmetry in final states with jets, missing transverse momentum and one isolated lepton in sqrt{s} = 7 TeV pp collisions using 1 fb-1 of ATLAS data

We present an update of a search for supersymmetry in final states containing jets, missing transverse momentum, and one isolated electron or muon, using 1.04 fb^-1 of proton-proton collision data at sqrt{s} = 7 TeV recorded by the ATLAS experiment at the LHC in the first half of 2011. The analysis is carried out in four distinct signal regions with either three or four jets and variations on the (missing) transverse momentum cuts, resulting in optimized limits for various supersymmetry models. No excess above the standard model background expectation is observed. Limits are set on the visible cross-section of new physics within the kinematic requirements of the search. The results are interpreted as limits on the parameters of the minimal supergravity framework, limits on cross-sections of simplified models with specific squark and gluino decay modes, and limits on parameters of a model with bilinear R-parity violation.Comment: 18 pages plus author list (30 pages total), 9 figures, 4 tables, final version to appear in Physical Review

Reducing heterotic M-theory to five dimensional supergravity on a manifold with boundary

This paper constructs the reduction of heterotic $M$-theory in eleven dimensions to a supergravity model on a manifold with boundary in five dimensions using a Calabi-Yau three-fold. New results are presented for the boundary terms in the action and for the boundary conditions on the bulk fields. Some general features of dualisation on a manifold with boundary are used to explain the origin of some topological terms in the action. The effect of gaugino condensation on the fermion boundary conditions leads to a `twist' in the chirality of the gravitino which can provide an uplifting mechanism in the vacuum energy to cancel the cosmological constant after moduli stabilisation.Comment: 16 pages, RevTe