State University of Santa Cruz

About: State University of Santa Cruz is a education organization based out in Ilhéus, Brazil. It is known for research contribution in the topics: Population & Species richness. The organization has 3266 authors who have published 4642 publications receiving 51876 citations. The organization is also known as: Universidade Estadual de Santa Cruz.

Tropical forest loss and its multitrophic effects on insect herbivory.

Abstract: Forest loss threatens biodiversity, but its potential effects on multitrophic ecological interactions are poorly understood. Insect herbivory depends on complex bottom-up (e.g., resource availability and plant antiherbivore defenses) and top-down forces (e.g., abundance of predators and herbivorous), but its determinants in human-altered tropical landscapes are largely unknown. Using structural equation models, we assessed the direct and indirect effects of forest loss on insect herbivory in 40 landscapes (115 ha each) from two regions with contrasting land-use change trajectories in the Brazilian Atlantic rainforest. We considered landscape forest cover as an exogenous predictor and (1) forest structure, (2) abundance of predators (birds and arthropods), and (3) abundance of herbivorous arthropods as endogenous predictors of insect leaf damage. From 12 predicted pathways, 11 were significant and showed that (1) leaf damage increases with forest loss (direct effect); (2) leaf damage increases with forest loss through the simplification of vegetation structure and its associated dominance of herbivorous insects (indirect effect); and further demonstrate (3) a lack of top-down control of herbivores by predators (birds and arthropods). We conclude that forest loss favors insect herbivory by undermining the bottom-up control (presumably reduced plant antiherbivore defense mechanisms) in forests dominated by fast-growing pioneer plant species, and by improving the conditions required for herbivores proliferation.

How colorful are fruits? Limited color diversity in fleshy fruits on local and global scales

Abstract: Summary The colors of fleshy fruits are considered to be a signal to seed-dispersing animals, but their diversity remains poorly understood. Using an avian color space to derive a sensory morphospace for fruit color, we tested four hypotheses of fruit color diversity: fruit colors occupy a limited area of the color space; they are less diverse than flower colors; fruit colors within localities are similar to each other; and fruit color diversity reflects phylogeny. The global fruit color diversity of 948 primarily bird-dispersed plant species and the color diversity of localities were compared with null models of random, unconstrained evolution of fruit color. Fruit color diversity was further compared with the diversity of 1300 flower colors. Tests of phylogenetic effects on fruit color were used to assess the degree of correspondence with phylogeny. Global and local fruit color diversity was limited compared with null models and fruits have achieved only half the color diversity of flowers. Interestingly, we found little indication of phylogenetic conservatism. Constraints resulting from the chemical properties of pigments probably limit global fruit and flower color diversity. Different types of selection on fruits and flowers may further explain the smaller color diversity of fruits.

Bioactive Oleanane, Lupane and Ursane Triterpene Acid Derivatives

Abstract: Betulinic, ursolic and oleanolic acids isolated from the aerial parts of Eriope blanchetii (Lamiaceae) were subjected to different esterification reactions, yielding 12 C-3 position ester derivatives. All compounds were identified using spectroscopic techniques, such as IR, 1H-NMR and MS. The derivatives were further investigated for their antioxidant level, Artemia salina lethality and antimicrobial activity.

Modeling population dynamics and conservation of arapaima in the Amazon

Abstract: To promote understanding of fish population dynamics in tropical river-floodplains, we have synthesized existing information by developing a largely empirical population model for arapaima (Arapaima sp.). Arapaima are characterized by very large bodies, relatively late sexual maturity, small clutches, and large parental investment per offspring, and their populations are overexploited and even declining due to overfishing. We used unparalleled time series data on growth, reproduction, catch-at-age, and size-class abundance estimates for a population that has increased several-fold and undergone drastic changes in fishing practices in the Amazon, Brazil. Model population numbers were close to observed numbers, with generally low mean absolute percentage errors for juveniles (16%), adults (30%), and catch (18%). In using the model to test ecological hypotheses and to investigate management strategies, we found the following: (1) Annual recruitment is directly and positively related to spawner abundance, and it appears to be density-compensatory following a Beverton–Holt relation (R 2 = 0.85). (2) Fishing-selectivity of arapaima caused by use of harpoons and gillnets can lower yield potentials dramatically through removal of the faster-growing individuals of the population. That is in part because fewer individuals live long enough to reproduce and survivors take longer to reach reproductive age. (3) Arapaima populations can sustain annual catches of up to 25% of the number of adults in the population the previous year if minimum size (1.5 m) and closed season (December–May) limits are met. (4) When 25% of the number of adults in the population the previous year is harvested under a 1.6 m minimum size limit of catch, catches are slightly smaller but abundance of adults in the population is considerably greater than under a 1.5 m limit. These findings can be used in ongoing management initiatives, but caution is needed because of present biological and ecological uncertainty about these fishes.

Confiabilidade da versão brasileira da escala de atividades instrumentais da vida diária - doi:10.5020/18061230.2008.p290

Abstract: Objective: To analyze the reliability of the Scale of Instrumental Activities of Daily Living (IADL) developed by Lawton and Brody and adapted to Brazilian context. Methods: A cross-sectional analytical study, with 16 women from groups of acquaintanceship, aged 60 to 89 years. In data collection, an individual interview was applied to assess the functional condition of the elderly and the accomplishment of strength testing of upper and lower limbs. Procedures of descriptive and inferential statistics were used for data analysis, by using the correlation intra-class index for obtaining the agreement among the tests for the same examiner (reliability) and for different evaluators (objectivity). The concurrent validity was obtained using Spearman’s correlation for the comparison of self-reported measures and those obtained by strength tests. We established a significance level of 5% with a confidence interval of 95%. Results: Concerning the stability of the measures, they can be classified as almost perfect agreement, both for the reliability (Ricc=0.89) as for the objectivity (Ricc=0.80). In concurrent validity, we observed a moderate relationship between the strength of upper limbs and the referred functional condition (rho=0.53); yet the relationship was not significant regarding the strength of lower limbs. Conclusions: The analysis of the data allows us to affirm that the scale of IADL presents satisfactory psychometric indexes. However, the concurrent validity evidenced that the scale only presents agreement in reference to the force of upper limbs.