Description and phylogenetic relationships of a new species of treefrog of the Dendropsophus leucophyllatus group (Anura: Hylidae) from the Amazon basin of Colombia and with an exceptional color pattern

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Growth of euterpe oleracea seedlings under different color nets and light conditions

Euterpe oleracea, a native palm to the Amazon, has recognized trading importance because of its fruits and heart of palm. However, it still requires general information on its propagation and cultivation. As light is essential for plant growth, this work aimed to study the effect of different color nets and light conditions on the initial growth of E. oleracea, with the objective to obtain high quality seedlings. The experiment was conducted in Jaboticabal County, São Paulo State, Brazil. The experimental design was entirely randomized, with six treatments (six light conditions: red net with 50% of shading - red Chromatinet®; blue net with 50% of shading - blue Chromatinet®; black nets with 70, 50 or 30% of shading; and full sun) and six replications (six evaluation periods: 30, 60, 90, 120, 150 and 180 days after the beginning of the experiment). Each plot consisted of four pots with one plant per pot, resulting in 144 plants. Seedling growth was monthly evaluated by collecting four plants per replication until the end of the experiment. Shoot length, root length, stem diameter, leaf number, leaf area and root and shoot dry matter were evaluated. The best quality seedlings of E. oleracea were obtained when they were cultivated under the black net with 50% of shading.

Can savannas become forests? A coupled analysis of nutrient stocks and fire thresholds in central Brazil

Aims: The effects of fire ensure that large areas of the seasonal tropics are maintained as savannas. The advance of forests into these areas depends on shifts in species composition and the presence of sufficient nutrients. Predicting such transitions, however, is difficult due to a poor understanding of the nutrient stocks required for different combinations of species to resist and suppress fires. Methods: We compare the amounts of nutrients required by congeneric savanna and forest trees to reach two thresholds of establishment and maintenance: that of fire resistance, after which individual trees are large enough to survive fires, and that of fire suppression, after which the collective tree canopy is dense enough to minimize understory growth, thereby arresting the spread of fire. We further calculate the arboreal and soil nutrient stocks of savannas, to determine if these are sufficient to support the expansion of forests following initial establishment. Results: Forest species require a larger nutrient supply to resist fires than savanna species, which are better able to reach a fire-resistant size under nutrient limitation. However, forest species require a lower nutrient supply to attain closed canopies and suppress fires; therefore, the ingression of forest trees into savannas facilitates the transition to forest. Savannas have sufficient N, K, and Mg, but require additional P and Ca to build high-biomass forests and allow full forest expansion following establishment. Conclusions: Tradeoffs between nutrient requirements and adaptations to fire reinforce savanna and forest as alternate stable states, explaining the long-term persistence of vegetation mosaics in the seasonal tropics. Low-fertility limits the advance of forests into savannas, but the ingression of forest species favors the formation of non-flammable states, increasing fertility and promoting forest expansion. © 2013 Springer Science+Business Media Dordrecht.

Fruit color and contrast in seasonal habitats - a case study from a cerrado savanna

Communication contributes to mediate the interactions between plants and the animals that disperse their genes. As yet, seasonal patterns in plant-animal communication are unknown, even though many habitats display pronounced seasonality e.g. when leaves senescence. We thus hypothesized that the contrast between fruit displays and their background vary throughout the year in a seasonal habitat. If this variation is adaptive, we predicted higher contrasts between fruits and foliage during the fruiting season in a cerrado-savanna vegetation, southeastern Brazil. Based on a six-year data base of fruit ripening and a one-year data set of fruit biomass, we used reflectance measurements and contrast analysis to show that fruits with distinct colors differed in the beginning of ripening and the peak of fruit biomass. Black, and particularly red fruits, that have a high contrast against the leaf background, were highly seasonal, peaking in the wet season. Multicolored and yellow fruits were less seasonal, not limited to one season, with a bimodal pattern for yellow ones, represented by two peaks, one in each season. We further supported the hypothesis that seasonal changes in fruit contrasts can be adaptive because fruits contrasted more strongly against their own foliage in the wet season, when most fruits are ripe. Hence, the seasonal variation in fruit colors observed in the cerrado-savanna may be, at least partly, explicable as an adaptation to ensure high conspicuousness to seed dispersers. © 2013 The Authors.

Chromatic characteristics and color-related phenolic composition of Brazilian young red wines made from the hybrid grape cultivar BRS Violeta (BRS Rúbea×IAC 1398-21)

The color characteristics and the phenolic composition related to color of young red wines elaborated with the hybrid grape cultivar BRS Violeta, developed for its adaptation to sub-tropical climates in Brazil, have been studied. These wines are characterized with a deep red-purplish color, reaching color intensity averaging 24 units. In spite of being young red wines elaborated with short maceration time, their content in total polyphenols was very high (around 3692. mg/L, as gallic acid equivalents), especially when compared to similar Vitis vinifera young red wines. Within polyphenols, anthocyanins predominated (around 2037. mg/L, as malvidin 3,5-diglucoside equivalents) and they were almost exclusively anthocyanidin 3,5-glucosides (ca. 97%), mainly built from B-ring tri-substituted anthocyanidins (delphinidin. >. petunidin. ≈. malvidin) and having high proportion of p-coumaroylated derivatives (ca. 28%) that confer higher stability. The content of hydroxycinnamic acid derivatives was also remarkable (ca. 95. mg/L, as caffeic acid equivalents) and unknown glucose derivatives of p-coumaric acid accounted for ca. 42% of total HCAD. Finally, these found flavonols were mainly based on myricetin whereas kaempferol derivatives were missing, their total content being within the ranges usually found for V. vinifera wines, but reaching their top values (ca. 91. mg/L, as quercetin 3-glucoside equivalents). All the aforementioned data suggest that Violeta wine could be considered an important dietary source of healthy polyphenols with a moderate alcoholic content (ca. 11.6%). © 2013 Elsevier Ltd.

Experimental poverty thresholds for the United States 1990 to 1998

Includes bibliography

Desempenho de métodos baseados na indução de fluorescência para a detecção de lesões de cárie em superfícies oclusais e proximais: estudos in vitro

Pós-graduação em Ciências Odontológicas - FOAR

Relação do Color Doppler e Power Doppler com densidade micro vascular intra tumoral corada com o anticorpo CD34 no câncer de mama

Pós-graduação em Ginecologia, Obstetrícia e Mastologia - FMB

Impacto da mastite subclínica na reprodução de vacas leiteiras

Pós-graduação em Zootecnia - FMVZ

El yo y el otro: alteridad próxima en la declaración del color y la raza en preguntas abiertas. El caso de la Encuesta Mensual de Empleo del Instituto Brasileño de Geografía y Estadística

Incluye bibliografía

Utilização da técnica VxIAT para a determinação de volumes de precipitação na área central do Estado de São Paulo

Pós-graduação em Agronomia (Energia na Agricultura) - FCA

A homotextualidade em “El color del verano”, de Reinaldo Arenas, ou quando o desejo assume corpo no texto

Pós-graduação em Letras - FCLAS

In vivo color changes of esthetic orthodontic ligatures

OBJETIVO: avaliar as alterações de cor ocorridas em elastômeros estéticos de quatro marcas comerciais, quando expostos ao meio bucal. MÉTODOS: foram examinadas as quatro marcas comerciais mais citadas por ortodontistas — Morelli, Uniden, American Orthodontics (AO) e TP —, em 25 pacientes consecutivos. Os elastômeros foram distribuídos de forma aleatória e ordenados nas quatro hemiarcadas de cada paciente, permanecendo no meio bucal por 30 dias. Após esse período, duas unidades de cada marca em todos os pacientes foram fotografadas de forma padronizada para, posteriormente, serem analisadas através de avaliação visual quanto à variação de cor, por escores (0, 1, 2, 3), por um painel de quatro examinadores. Os escores médios dos examinadores foram analisados estatisticamente por meio da ANOVA e teste de Tukey, com p<0,05. RESULTADOS: os escores médios de pigmentação, após 30 dias no meio intrabucal, obtidos para os elastômeros Morelli (1,80±0,78) e Uniden (1,92±0,66) não foram estatisticamente diferentes entre si. Entretanto, essas marcas estavam significativamente mais pigmentadas após 30 dias no meio intrabucal (p<0,01) quando comparadas às marcas importadas, American Orthodontics (0,97±0,6) e TP (0,83±0,79). CONCLUSÃO: apesar de todas as quatro marcas apresentarem uma indesejável pigmentação após 30 dias no meio intrabucal, as marcas American Orthodontics e TP apresentaram alterações de cor menos significativas do que as marcas Morelli e Uniden.

Um teste computadorizado para a avaliação de visão de cores em crianças e sujeitos não-verbais baseado no teste de discriminação de cores de Mollon-Reffin

O presente estudo visou garantir condições favoráveis para a avaliação de discriminação de cores em crianças, por meio de uma adaptação no modo Trivector do teste de discriminação de cores de Mollon-Reffin. Como a tarefa original, de indicar a abertura do C de Landolt, se mostrou pouco intuitiva para crianças pequenas, o alvo foi mudado para uma área colorida aproximadamente quadrada e a resposta requerida passou a ser tocar no alvo. O modo de teste Trivector mede os limiares de discriminação de cor ao longo de três linhas de confusão características das três formas variantes de visão de cor humana: protan-, deutan- e tritan-. O Experimento I avaliou a concordância entre o teste original e a versão adaptada, com 29 sujeitos adultos com visão de cor normal. A comparação dos limiares obtidos com as duas versões, por meio do método de avaliação de concordância de Bland-Altman, mostrou boa concordância entre as versões. No Experimento II, o teste adaptado foi aplicado em 25 crianças de 2 a 7 anos, usando técnicas de treino operante para estabelecer e manter o desempenho dos sujeitos. Os limiares diminuíram progressivamente acompanhando o aumento na idade. Os limiares protan- e deutan- foram consistentemente menores que os limiares tritan-, um padrão que já havia sido observado com adultos no teste original. Os resultados demonstram que, feitas as adaptações necessárias, o teste é adequado para a avaliação da discriminação de cor em crianças pequenas e pode ser uma ferramenta útil para a identificação das variações da visão de cor durante o desenvolvimento, bem como para a aplicação em outras populações humanas e, inclusive, outros primatas. (CNPq, FINEP).

Estimativa da sensibilidade ao contraste espacial de luminância e discriminação de cores por meio do potencial provocado visual transiente

O potencial provocado visual (VEP) é uma resposta cortical registrável na superfície do couro cabeludo, que reflete a atividade dos neurônios de V1. É classificado, a partir da freqüência temporal de estimulação, em transiente ou de estado estacionário. Outras propriedades do estímulo parecem provocar uma atividade seletiva dos diversos grupos de neurônios existentes em V1. Desse modo, o VEP vem sendo usado para estudar a visão humana acromática e cromática. Diversos trabalhos usaram o VEP para estimar a sensibilidade ao contraste de luminância no domínio das freqüências espaciais. Mais recentemente, há estudos que empregaram o VEP para medir os limiares de discriminação de cores. O VEP transiente pode complementar as medidas psicofísicas de sensibilidade ao contraste espacial de luminância e de discriminação cromática, e constitui um método não invasivo para estudar a visão de indivíduos com dificuldades de realizar testes psicofísicos.