Morphodynamics of headland-bay beaches: Examples from the Coast of Santa Catarina state, Brazil

The overall goal of this study is to contribute to increased understanding of headland-bay beach morphodynamics, z'.e to elucidate the interaction between hydrodynarnic processes, beach morphology and sedimentology at Large Scale Coastal Behaviour in the c oastline o f S anta C atarina, b etween L aguna and S ão Francisco, an east coast swell enviromnent with headland and bay geomorphologies. In order to investigate morphodynamic processes, beach planforms for 90 beaches on the Santa Catarina coast were analyzed by utilizing maps and aerial photography at different scales. An intensive field investigation of m orphologic and sedimentological changes was conducted on 28 beaches in central-north Santa Catarina coast from May 1994 to March 1996, where morphological and sedimentological changes were related to spatial variations in wave/tidal and sedimentary provenance conditions. Field investigations were additionally conducted on three beaches in an effort to determine alongshore sediment mobility at headland-bay beaches. In this case, temporal morphological changes were correlated with wave information (wave height, period and direction obtained from visual beach observations and wave forecast models).O objetivo principal deste estudo é contribuir para o aumento do entendimento da morfodinâmica de praias de enseada, isto é, elucidar a interação entre processos hidrodinâmicos, morfologia e sedimentologia praial em meso e macro escala. A área de estudo compreende as praias do estado de Santa Catarina, entre Laguna e São Francisco, as quais se encontram em uma zona costeira que recebe ondulações provenientes de leste e apresenta uma geomorfologia composta de promontórios e baias. Para a definir a forma em planta, 90 praias forarn analisadas utilizando-se de mapas e fotografia aéreas em diferentes escalas. Um programa intensivo de levantamento de campo das mudanças morfológicas e sedimentológicas foi conduzido em 28 praias no litoral centro-norte de Santa Catarina, entre Maio de 1994 e Março de 1996. As mudanças morfológicas e sedimentológicas foram relacionadas com variações espaciais nas condições das ondas/marés, bem como proveniência dos sedimentos. Adicionalmente, foram conduzidos levantamentos morfológicos em três praias (Praia Brava, Balneário Camboriú e Taquaras/Taquarinhas) para determinar-se o transporte de sedimento ao longo da costa em praias de enseada. Neste caso, as variações morfológicas foram relacionadas com observações visuais e previsões de ondas

Smoothed Analysis of the Minimum-Mean Cycle Canceling Algorithm and the Network Simplex Algorithm

The minimum-cost flow (MCF) problem is a fundamental optimization problem with many applications and seems to be well understood. Over the last half century many algorithms have been developed to solve the MCF problem and these algorithms have varying worst-case bounds on their running time. However, these worst-case bounds are not always a good indication of the algorithms' performance in practice. The Network Simplex (NS) algorithm needs an exponential number of iterations for some instances, but it is considered the best algorithm in practice and performs best in experimental studies. On the other hand, the Minimum-Mean Cycle Canceling (MMCC) algorithm is strongly polynomial, but performs badly in experimental studies. To explain these differences in performance in practice we apply the framework of smoothed analysis. We show an upper bound of $O(mn^2\log(n)\log(\phi))$ for the number of iterations of the MMCC algorithm. Here $n$ is the number of nodes, $m$ is the number of edges, and $\phi$ is a parameter limiting the degree to which the edge costs are perturbed. We also show a lower bound of $\Omega(m\log(\phi))$ for the number of iterations of the MMCC algorithm, which can be strengthened to $\Omega(mn)$ when $\phi=\Theta(n^2)$. For the number of iterations of the NS algorithm we show a smoothed lower bound of $\Omega(m \cdot \min \{ n, \phi \} \cdot \phi)$.Comment: Extended abstract to appear in the proceedings of COCOON 201

Aprendizagem significativa do tema “fotossíntese” no ensino fundamental: um relato de experiência

Anais do II Seminário Seminário Estadual PIBID do Paraná: tecendo saberes / organizado por Dulcyene Maria Ribeiro e Catarina Costa Fernandes — Foz do Iguaçu: Unioeste; Unila, 2014Um dos principais problemas no ensino de ciências está no distanciamento do conteúdo teórico proposto pelo docente à realidade de vida do aluno. Como o tema da fotossíntese apresenta-se de forma abstrata e distante do cotidiano do aprendiz, este trabalho apresenta como alternativa uma atividade experimental, baseada na construção, discussão e observação dos resultados. Dessa forma, a interação entre o professor e os alunos são pontos principais na identificação dos conhecimentos prévios dos estudantes e conceitualização do tema proposto. Como resultado observa-se maior participação e interesse da turma na implementação das atividades proposta

Circulating markers of arterial thrombosis and late-stage age-related macular degeneration: a case-control study.

PURPOSE: The aim of this study was to examine the relation of late-stage age-related macular degeneration (AMD) with markers of systemic atherothrombosis. METHODS: A hospital-based case-control study of AMD was undertaken in London, UK. Cases of AMD (n=81) and controls (n=77) were group matched for age and sex. Standard protocols were used for colour fundus photography and to classify AMD; physical examination included height, weight, history of or treatment for vascular-related diseases and smoking status. Blood samples were taken for measurement of fibrinogen, factor VIIc (FVIIc), factor VIIIc, prothrombin fragment F1.2 (F1.2), tissue plasminogen activator, and von Willebrand factor. Odds ratios from logistic regression analyses of each atherothrombotic marker with AMD were adjusted for age, sex, and established cardiovascular disease risk factors, including smoking, blood pressure, body mass index, and total cholesterol. RESULTS: After adjustment FVIIc and possibly F1.2 were inversely associated with the risk of AMD; per 1 standard deviation increase in these markers the odds ratio were, respectively, 0.62 (95% confidence interval 0.40, 0.95) and 0.71 (0.46, 1.09). None of the other atherothrombotic risk factors appeared to be related to AMD status. There was weak evidence that aspirin is associated with a lower risk of AMD. CONCLUSIONS: This study does not provide strong evidence of associations between AMD and systematic markers of arterial thrombosis, but the potential effects of FVIIc, and F1.2 are worthy of further investigation

Quarkonium suppression from SPS to RHIC (and from p+A to A+A)

Heavy quarkonia production is expected to be sensitive to the formation of a quark gluon plasma (QGP). It was (and still is with ongoing data analyses) extensively studied at the CERN SPS, at collision energy $\sqrt{s_{NN}}$ of the order of 20 GeV. An anomalous suppression was clearly observed. The PHENIX experiment at RHIC has presented preliminary results that exhibit a similar amount of $J/\psi$ suppression, at ten times higher collision energy. I review the results obtained at both facilities. While interpreting and comparing them, the importance of understanding normal nuclear effects is emphasized. A new method to derive a reference for Au+Au collisions from the centrality dependence of d+Au measurements at RHIC is exposed.Comment: Plenary talk given at Hard Probes 2006, June 9-16, 2006, Asilomar, CA, USA; 8 pages, 8 figure

Finite Temperature Many-Body Theory with the Lipkin Model

We have compared exact numerical results for the Lipkin model at finite temperature with Hartree-Fock theory and with the results of including in addition the ring diagrams. In the simplest version of the Lipkin model the Hartree-Fock approach shows a ``phase transition" which is absent in the exact results. For more realistic cases, Hartree-Fock provides a very good approximation and a modest improvement is obtained by adding the ring diagrams.Comment: 17 pages, NUC-MINN-93/16-T (4 figures obtainable by fax from the authors

Wave run-up on embayed beaches. Study case: Itapocorói Bay, Southern Brazil

This paper presents a new approach for estimating run-up on embayed beaches based on a study of the microtidal coast of Itapocorói Bay, Southern Brazil using the surf similarity parameter and wave height at break location. The four step methodology involved: 1) direct wave measurement (34 days), wave run-up measurement (19 days at 7 points within the bay), measurement of bathymetry and beach topography in the entire bay; 2) tests on available formulae to calculate wave run-up; 3) use of the SWAN spectral wave model to simulate wave parameters at breaking at each wave run-up measurement point and; 4) development of a new formula/approach to assess wave run-up on embayed beaches (in both exposed and protected areas). During the experiments the significant wave height varied from 0.5 m to 3.01 m, the mean wave period from 2.79 s to 7.76 s (the peak period varied between 2.95 s and 17.18 s), the mean wave direction from 72.5° to 141.9° (the peak direction varied from 39.2° to 169.8°) and the beach slope (tan β) from 0.041 to 0.201. The proposed formula is in good agreement with measured data for different wave conditions and varying degrees of protection. The analysis demonstrates that although R² varies from 0.52 to 0.75, the wave run-up distribution over the measurements agreed well with the proposed model, as shown by quantile-quantile analysis (R²=0.98 to 0.99). The errors observed in individual cases may be related to errors of measurements, modeling and to non-linear processes in the swash zone, such as infragavity waves.Este artigo tem o objetivo de estimar o run-up em praias de enseada a partir de estudo realizado na Enseada do Itapocorói, localizada em uma costa de micromarés no sul do Brasil utilizando o parâmetro de similaridade de surf (surf similarity parameter) e altura de ondas no ponto de quebra. A metodologia aplicada foi dividida em quatro etapas: 1) medição direta de ondas (34 dias), medidas de wave run-up (19 dias em 7 pontos da baía), medições topo-batimétricas; 2) testes com as fórmulas disponíveis na literatura para cálculo do run-up; 3) uso do modelo espectral SWAN para simular a propagação das ondas e obter os parâmetros de ondas no ponto de quebra no momento das medições do run-up e; 4) desenvolvimento de uma nova abordagem para estimar o run-up em praias de enseada (aplicável às áreas protegidas e expostas da enseada). Os resultados demonstram que, durante os experimentos, a altura significativa de onda variou entre 0,5 e 3,01 m, o período médio entre 1,79 e 7,76 s (o período de pico entre 2,95 e 17,19 s), a direção média entre 72,5° e 141,9° (a direção de pico entre 39,2° e 169,8°) e a declividade da face da praia (tan β) entre 0,041 e 0,201. A fórmula proposta apresenta boa concordância com os dados medidos para diferentes condições de ondas e graus de proteção da praia. Como conclusão destaca-se que, apesar do R² variar entre 0,52 e 0,75, a distribuição das medições de run-up apresentou boa concordância com o modelo proposto, como demonstrado pela análise quantil-quantil (R²=0,98 a 0,99). Os erros observados em casos individuais podem estar relacionados a erros das medições, do modelo e aos processos não lineares presentes na zona de espraiamento, como as ondas de infragravidade

An Analogue of Holstein-Primakoff and Dyson Realizations for Lie Superalgebras. The Lie superalgebra sl(1/n)

An analogue of the Holstein-Primakoff and of the Dyson realization for the Lie superalgebra $sl(1/n)$ is written down. The expressions are formally the same as for the Lie algebra $sl(n+1)$, however in the latter the Bose operators have to be replaced with Fermi operators.Comment: TeX, 6 page

New estimation of Sobol' indices using kernels

In this work, we develop an approach mentioned by da Veiga and Gamboa in 2013. It consists in extending the very interestingpoint of view introduced in \cite{gine2008simple} to estimate general nonlinear integral functionals of a density on the real line, by using empirically a kernel estimator erasing the diagonal terms. Relaxing the positiveness assumption on the kernel and choosing a kernel of order large enough, we are able to prove a central limit theorem for estimating Sobol' indices of any order (the bias is killed thanks to this signed kernel)