Evaluating the effectiveness of undergraduate courses at the Federal University of Ceará (UFC) through the Data Envelopment Analysis (DEA)

O texto apresenta dados oriundos de pesquisa sobre a eficiência dos cursos de graduação da Universidade Federal do Ceará (UFC) entre os anos 2006 e 2009, com base em indicadores de insumos (inputs) e de resultados (outputs). Para tal empregou-se o método Data Envelopment Analysis (DEA), numa amostra não probabilística de 30 cursos de graduação. Adotando-se como indicador de output o número de alunos concludentes, constatou-se que, em média, a quantidade de concludentes está muito abaixo da quantidade de alunos ingressantes, durante todo o período analisado. Aplicando-se a modelagem completa do método DEA, com ênfase nos indicadores de output (alunos concludentes), os resultados mostram que existe um grupo de nove DMU (decision making units), o que equivale a 30% dos cursos analisados que permaneceram, ao longo do tempo, no nível máximo de eficiência. De forma análoga, constatamos cinco DMU (16,7%) que, ao longo do tempo, permaneceram sempre ineficientes, com valores de eficiência relativa abaixo de 80% (padrão mínimo de eficiência relativa).El texto presenta datos oriundos de investigación sobre la eficiencia de los cursos de graduación de la Universidad Federal de Ceará (UFC) entre los años 2006 y 2009, con base en indicadores de insumos (inputs) y de resultados (outputs). Para tal se empleó el método Data Envelopment Analysis (DEA), en una muestra no probabilística de 30 cursos de graduación. Adoptándose como indicador de output el número de alumnos concluyentes, se constató que, en media, la cantidad de concluyentes está mucho rebajo de la cantidad de alumnos ingressantes, durante todo el periodo analizado. Aplicándose la modelagem completa del método DEA, con énfasis en los indicadores de output (alumnos concluyentes), los resultados muestran que existe un grupo de nueve DMU (decision making units), lo que equivale la un 30% de los cursos analizados que permanecieron, al largo del tiempo, en el nivel máximo de eficiencia. De forma análoga, constatamos cinco DMU (un 16,7%) que, al largo del tiempo, permanecieron siempre ineficientes, con valores de eficiencia relativa abajo del 80% (patrón mínimo de eficiencia relativa).The paper presents data from research on the effectiveness of undergraduate courses at the Federal University of Ceará (UFC) between the years 2006 and 2009, based on indicators of inputs and outputs. For this method utilizes the Data Envelopment Analysis (DEA), a non-probability sample of 30 undergraduate courses. Adopting as output indicator the number of students conclusive, it was found that on average, the amount of conclusive is far below the amount of new students during the whole period. Applying the complete modeling of the DEA, with emphasis on output indicators (student conclusive), the results show that there is a group of nine DMUs (decision making units), equivalent to 30% of the courses analyzed, which remained at the over time, the highest level of efficiency. Similarly, we found five DMUs (16.7%) which, over time, always remained inefficient, with values ​​of relative efficiency below 80% (minimum standard of efficiency relative)

Diffusion entropy analysis on the scaling behavior of financial markets

In this paper the diffusion entropy technique is applied to investigate the scaling behavior of financial markets. The scaling behaviors of four representative stock markets, Dow Jones Industrial Average, Standard&Poor 500, Heng Seng Index, and Shang Hai Stock Synthetic Index, are almost the same; with the scale-invariance exponents all in the interval $[0.92, 0.95]$. These results provide a strong evidence of the existence of long-rang correlation in financial time series, thus several variance-based methods are restricted for detecting the scale-invariance properties of financial markets. In addition, a parsimonious percolation model for stock markets is proposed, of which the scaling behavior agrees with the real-life markets well.Comment: 5 pages, 3 figure

A joint experimental and theoretical study on the electronic structure and photoluminescence properties of Al2(WO4)3 powders

In this paper, aluminum tungstate Al2(WO4)3 powders were synthesized using the co-precipitation method at room temperature and then submitted to heat treatment processes at different temperatures (100, 200, 400, 800, and 1000 °C) for 2 h. The structure and morphology of the powders were characterized by means of X-ray diffraction (XRD), Rietveld refinement data, and field emission scanning electron microscopy (FE-SEM) images. Their optical properties were examined with ultraviolet-visible (UV-vis) diffuse reflectance spectroscopy and photoluminescence (PL) measurements. XRD patterns and Rietveld refinement data showed that Al2(WO4)3 powders heat treated at 1000 °C for 2 h have a orthorhombic structure with a space group (Pnca) without the presence of deleterious phases. FE-SEM images revealed that these powders are formed by the aggregation of several nanoparticles leading to the growth of microparticles with irregular morphologies and an agglomerated nature. UV-vis spectra indicated that optical band gap energy increased from 3.16 to 3.48 eV) as the processing temperature rose, which was in turn associated with a reduction in intermediary energy levels. First-principle calculations were performed in order to understand the behavior of the PL properties using density functional theory at the B3LYP calculation level on periodic model systems and indicate the presence of stable electronic excited states (singlet). The analyses of the band structures and density of states at both ground and first excited electronic states provide insight into the main features, based on structural and electronic order-disorder effects in octahedral [AlO6] clusters and tetrahedral [WO4] clusters, as constituent building units of this material

Fetal cardiotocography before and after water aerobics during pregnancy

<p>Abstract</p> <p>Objective</p> <p>To evaluate the effect of moderate aerobic physical activity in water on fetal cardiotocography patterns in sedentary pregnant women.</p> <p>Method</p> <p>In a non-randomized controlled trial, 133 previously sedentary pregnant women participated in multiple regular sessions of water aerobics in a heated swimming pool. Cardiotocography was performed for 20 minutes before and just after the oriented exercise. Cardiotocography patterns were analyzed pre- and post-exercise according to gestational age groups (24-27, 28-31, 32-35 and 36-40 weeks). Student's t and Wilcoxon, and McNemar tests were used, respectively, to analyze numerical and categorical variables.</p> <p>Results</p> <p>No significant variations were found between pre- and post-exercise values of fetal heart rate (FHR), number of fetal body movements (FM) or accelerations (A), FM/A ratio or the presence of decelerations. Variability in FHR was significantly higher following exercise only in pregnancies of 24-27 weeks.</p> <p>Conclusions</p> <p>Moderate physical activity in water was not associated with any significant alterations in fetal cardiotocography patterns, which suggests no adverse effect on the fetus.</p

Nut production in Bertholletia excelsa across a logged forest mosaic: implications for multiple forest use

Although many examples of multiple-use forest management may be found in tropical smallholder systems, few studies provide empirical support for the integration of selective timber harvesting with non-timber forest product (NTFP) extraction. Brazil nut (Bertholletia excelsa, Lecythidaceae) is one of the world’s most economically-important NTFP species extracted almost entirely from natural forests across the Amazon Basin. An obligate out-crosser, Brazil nut flowers are pollinated by large-bodied bees, a process resulting in a hard round fruit that takes up to 14 months to mature. As many smallholders turn to the financial security provided by timber, Brazil nut fruits are increasingly being harvested in logged forests. We tested the influence of tree and stand-level covariates (distance to nearest cut stump and local logging intensity) on total nut production at the individual tree level in five recently logged Brazil nut concessions covering about 4000 ha of forest in Madre de Dios, Peru. Our field team accompanied Brazil nut harvesters during the traditional harvest period (January-April 2012 and January-April 2013) in order to collect data on fruit production. Three hundred and ninety-nine (approximately 80%) of the 499 trees included in this study were at least 100 m from the nearest cut stump, suggesting that concessionaires avoid logging near adult Brazil nut trees. Yet even for those trees on the edge of logging gaps, distance to nearest cut stump and local logging intensity did not have a statistically significant influence on Brazil nut production at the applied logging intensities (typically 1–2 timber trees removed per ha). In one concession where at least 4 trees ha-1 were removed, however, the logging intensity covariate resulted in a marginally significant (0.09) P value, highlighting a potential risk for a drop in nut production at higher intensities. While we do not suggest that logging activities should be completely avoided in Brazil nut rich forests, when a buffer zone cannot be observed, low logging intensities should be implemented. The sustainability of this integrated management system will ultimately depend on a complex series of socioeconomic and ecological interactions. Yet we submit that our study provides an important initial step in understanding the compatibility of timber harvesting with a high value NTFP, potentially allowing for diversification of forest use strategies in Amazonian Perù

Results from the first use of low radioactivity argon in a dark matter search

Liquid argon is a bright scintillator with potent particle identification properties, making it an attractive target for direct-detection dark matter searches. The DarkSide-50 dark matter search here reports the first WIMP search results obtained using a target of low-radioactivity argon. DarkSide-50 is a dark matter detector, using two-phase liquid argon time projection chamber, located at the Laboratori Nazionali del Gran Sasso. The underground argon is shown to contain Ar-39 at a level reduced by a factor (1.4 +- 0.2) x 10^3 relative to atmospheric argon. We report a background-free null result from (2616 +- 43) kg d of data, accumulated over 70.9 live-days. When combined with our previous search using an atmospheric argon, the 90 % C.L. upper limit on the WIMP-nucleon spin-independent cross section based on zero events found in the WIMP search regions, is 2.0 x 10^-44 cm^2 (8.6 x 10^-44 cm^2, 8.0 x 10^-43 cm^2) for a WIMP mass of 100 GeV/c^2 (1 TeV/c^2 , 10 TeV/c^2).Comment: Accepted by Phys. Rev.