RCAAP Repository

Vitamin C is essential for fish diets because many species cannot syntethize it. This vitamin is needed for bone and cartilage formation. Moreover, it acts as antioxidant and improve the immunological system. The present work investigated the effects of vitamin C diet supplementation to spotted sorubim (Pseudoplatystoma coruscans) fingerlings by frequency of bone and cartilage deformation. Ascorbyl poliphosphate (AP) was used as source of vitamin C in the diets for spotted sorubim fingerlings during three months. Six diets were formulated: one diet control (0 mg/kg of vitamin C) and 500, 1,000, 1,500, 2,000 and 2,500 mg AP/kg diets. Fishes fed without vitamin C supplementation presented bone deformation in head and jaws, and fin fragilities. Thus, 500 mg AP/kg diet was enough to prevent deformation and the lack of vitamin C supplementation worsening the development of fingerlings.

Intensive fish production systems are characterized by 100% artificial feeding, so any dietary imbalances or deficiencies may lead to diseases outbreaks and economic losses. This study was set out to determine the effects of increasing levels of dietary vitamin E on growth and hematology of juvenile pacu. Fishes were fed for 90 days, twice a day until apparent satiation with semi-purified diets containing 0.0; 25; 50; 150; 300 or 600 mg.kg−1 diet DL-α-tocopheryl acetate in a completely randomized design trial (n=4); biometrical and hematological data were collected and analyzed. Fishes fed with vit E diet (150 mg.kg−1) showed higher (p<0.05) weight gain and specific growth. Hematocrit, erythroblast number and total plasma protein were increased (p<0.05) in fishes fed diet with no vit E diet. Vitamin E supplementation in artificial diets for pacu is essential for growth and maintenance of normal erythropoiesis.

Conventional tillage (CT) and no-tillage (NT) management systems alter soil nutrient availability and consequently modify soil microbial response to nutrient additions such as carbon (C) and phosphorus (P). The objective of this study is to evaluate microbial response to the addition of C (glucose) and P (Na2HPO4.7H2O) under CT and NT in the brazilian Cerrado. In response to glucose addition, the NT system yielded higher microbial respiration rates and glucose consumption than the CT system. The best microbial response to C addition was after 0 - 12 h incubation in NT and 0 - 24 h in CT. The addition of P produced higher demand under CT than NT. After incubation, biochemical indicators such as microbial respiration, glucose consumption, dehydrogenase activity and metabolic yield confirmed the higher glucose demands under NT and higher phosphorus demands under CT. These results demonstrate that C and P addition alter significantly the microbial response, suggesting that soil microorganisms present nutrient differential demands between CT and NT management systems.

This paper presents the practical application of concepts, and some methods of risk analysis, to check the possibility of overcoming a water level of project in the spillway of dam Orós, by excess of influent flow. Also evaluated the empirical formulas contained in the original design. Due to the difficulty of obtaining design data from the dam, since the end of construction date of January, 11, 1961, we minimize the effects of some variables in the calculations, leading us to the consequent simplification of the scenario under study. For a better evaluation and characterization of the setting, some variables in the model such as water level, accumulation and flow of the spillway, had updated their data to June 28, 2011. We have demonstrated the importance of risk analysis for project design, construction and operation of large reservoirs, and the need for ongoing assessments of works of this nature.

Two distinct fishing technologies were identified among the shellmound builders of the Saquarema Lagoonal Complex, in the Brazilian state of Rio de Janeiro: bone point technology and worked fish spines. These technologies were related to the acquisition of specific fish resources; Worked fish spines were used in the capture of Micropogonias furnieri (Desmarest), and bone points used for fishing specimens of the Ariidae family. Worked spines technology was predominant between 6,726 cal. years BP and 3,699 cal. years BP, while the bone point technology was dominant after 3,699 cal. years BP. It is believed these different strategies for obtaining fishing resources before 3,699 years cal. BP was related to environmental. Notably the gradual regression of relative sea level occurred during the mid- and late Holocene.

The worldwide prestige of economists in the lay media lies significantly higher than scientists and academics from other fields of expertise. Brazil is not an exception as well. A point that calls attention to this fact is that the most prestigious international economists, who are frequently present in the lay media, are also distinguished in the academic environment. The lay prestige may be measured by their presence in the media and by surveys of public opinion, whereas academic prestige may be evaluated using database indicators of publications and citations of academic articles. One indicator that became frequently used is the h-index, measuring publications and citations simultaneously. A relevant finding regarding international economists is that both lay prestige and academic prestige are high and, apparently, mutually dependent. Among Brazilian economists, lay prestige is not accompanied by academic prestige. This last one is significantly low, even though doctorate studies in international universities of excellence are commonplace in these economists' curricula. The data point to a low intensity of academic life in Brazilian economics schools.

In this paper, we obtain vanishing theorems and finitely many ends theorems of complete Riemannian manifolds with weighted Poincaré inequality, applying them to minimal hypersurfaces.

Climate variations and historical land use had a major impact on landscape development in the Brazilian Atlantic Forest (Mata Atlântica). In southeast Brazil, rainforest expanded under warm-humid climate conditions in the late Holocene, but have been dramatically reduced in historical times. Nevertheless, the numerous remaining forest fragments are of outstanding biological richness. In our research in the Atlantic Forest of Rio de Janeiro we aim at the reconstruction of the late Quaternary landscape evolution and an assessment of human impact on landscapes and rainforests. In this context, special focus is given on (a) effects of climate variations on vegetation cover, soil development, and geomorphological processes, and (b) spatial and temporal land use and landscape degradation patterns. In this paper we present some new results of our interdisciplinary research in the Serra dos Órgãos mountain range, state of Rio de Janeiro.

The geographic distribution of 27 species of the South American megafauna of herbivore mammals during the Late Pleistocene was analyzed in order to identify their distributional patterns. The distribution of the species was studied using the panbiogeographical method of track analysis. Six generalized tracks (GTs) and two biogeographic nodes were obtained. The GTs did not completely superpose with the areas of open savanna present in Pleistocene, nor with the biotic tracks of some arthropods typical of arid climate, indicating that these animals avoided arid environment. Overall, the GTs coincided with some biogeographic provinces defined on the basis of living taxa, indicating that certain current distributional patterns already existed in Pleistocene. The biogeographic nodes coincided with the borders between the main vegetal formations of the Pleistocene, showing that the type of vegetation had great influence in the distribution of the mammalian megafauna. The node 1 confirmed the existence of contact zones between paleobiogeographic regions near Argentina-Uruguay border. The node 2 connects the Brazilian Intertropical regions.

We describe the nest, eggs, and nestlings of the Restinga Antwren (Formicivora littoralis), an endangered bird of Restinga ecosystem (sandy coastal plain vegetation) that is endemic to Rio de Janeiro state. Twelve nests were found at the edges of trails or natural gaps at Massambaba Restinga region, in different supporting plants and heights from the ground (X ± SD 1.27 ± 0.97 m, range 0.27 to 3.45 m). Nests were cup-shaped and were in horizontal forks attached to branches at three to five points with whitish, soft, and thin cotton-like vegetable fiber. The nests' cup shape and measurements were similar to congeneric species, but nest material was different. Eggs were white with brown spots concentrated on the large end or around the middle, giving the appearance of a rough brown ring. Their mean (± SD) minimum diameter was 13.1 ± 0.34 mm, with maximum diameter of 18.0 ± 0.38 mm, and mass of 1.7 ± 0.18 g (n = 8). We found two nestlings completely naked on their first day after hatching.

Solanum paniculatum L. is a plant species widespread throughout tropical America, especially in the Brazilian Cerrado region. It is used in Brazil for culinary purposes and in folk medicine to treat liver and gastric dysfunctions, as well as hangovers. Previous studies with S. paniculatum ethanolic leaf extract or ethanolic fruit extract demonstrated that they have no genotoxic activity neither in mice nor in bacterial strains, although their cytotoxicity and antigenotoxicity were demonstrated in higher doses. In order to assess the possible compounds responsible for the activities observed, we fractionated the ethanolic fruit extract of S. paniculatum, characterized by 1H and 13C NMR spectra, and evaluated two fractions containing steroidal alkaloids against mitomycin C (MMC) using the mouse bone marrow micronucleus test. Swiss mice were orally treated with different concentrations (25, 50, or 100 mg.kg−1) of each fraction simultaneously with a single intraperitonial dose of MMC (4 mg.kg−1). Antigenotoxicity was evaluated by using the frequency of micronucleated polychromatic erythrocytes (MNPCE), whereas anticytotoxicity was assessed by the polychromatic and normochromatic erythrocytes ratio (PCE/NCE). Our results demonstrated that steroidal alkaloids isolated from S. paniculatum strongly protected cells against MMC aneugenic and/or clastogenic activities as well as modulated MMC cytotoxic action.

Noni, a Hawaiian name for the fruit of Morinda citrifolia L., is a traditional medicinal plant from Polynesia widely used for the treatment of many diseases including arthritis, diabetes, asthma, hypertension and cancer. Here, a commercial noni juice (TNJ) was evaluated for its protective activities against the lesions induced by mitomycin C (MMC) and doxorrubicin (DXR) using the Somatic Mutation and Recombination Test (SMART) in Drosophila melanogaster. Three-day-old larvae, trans-heterozygous for two genetic markers (mwh and flr3 ), were co-treated with TNJ plus MMC or DXR. We have observed a reduction in genotoxic effects of MMC and DXR caused by the juice. TNJ provoked a marked decrease in all kinds of MMC- and DXR-induced mutant spots, mainly due to its antirecombinagenic activity. The TNJ protective effects were concentration-dependent, indicating a dose-response correlation, that can be attributed to a powerful antioxidant and/or free radical scavenger ability of TNJ.

The Streptoverticillium sp. Z1 is an actinomycete isolated from the soil under Cerrado vegetation, the extract of this strain was investigated in nociceptive and inflammatory models. The Streptoverticillium extract (ExS) 50 and 100 mg/kg (s.c.) produced a significant inhibition of acetic acid-induced abdominal writhings thereby demonstrating an anti-nociceptive effect. In the tail flick test the ExS (s.c.) was inactive. This result implited that ExS does not contain opioid-like compounds with central analgesic properties. In the inflammatory models, ExS 100 and 200 mg/kg (s.c.) were able to inhibit the croton oil-induced ear edema and, ExS 200 and 500 mg/kg (s.c.) inhibited the leukocyte migration on the carrageenan-induced peritonitis. The phospholipase A2 enzymatic assay showed that the anti-inflammatory activity of ExS was not due to direct effect on phospholipase A2 activity. These data suggest that Streptoverticillium sp. produces metabolites with anti-inflammatory effect and that these metabolites are unable to directly inhibit phospholipase A2 enzyme.

Melocactus violaceus is an endangered species due to habitat destruction and the overcollection of this species for ornamental use. The aim of this study was to test the effect of different temperatures on the germination of M. violaceus. Three treatments were conducted: a constant temperature of 25ºC, a 20-35ºC alternating temperature, both inside germination chamber, and an alternating temperature under room temperature (mean temperature ranged from 25-37ºC). The final seed germination rates at the alternating temperature treatments were not significantly different (65% in the seed germinator and 62.5% at room condition). However, both treatments with alternating temperatures had significantly higher germination rates compared to the treatment kept at the constant temperature (8%). Our study showed that alternating temperatures between 20 and 37ºC provides satisfactory conditions to induce a high percentage of seed germination of M. violaceus, without the passage of seeds through the digestive tract of its natural disperser, the lizard Tropidurus torquatus. This condition contributes to efficiently producing seedlings that can be reintroduced into conservation areas or used as ornamentals that may help reduce the overcollection of the remaining native populations.

The Deciduous Complex that occurs in northern Minas Gerais State, Brazil, raises questions about the floristic affinities of these formations in relation to neighboring phytogeographical domains. Little is known about the identity of the seasonal forest formations that comprise this complex, or about its relationships to abiotic components, such as soils, topography and climate. This study aimed to recognize the patterns of floristic similarity of all studied fragments of dry forest of northern Minas Gerais with soil and climate attributes, based on the available database. Cluster analysis indicated the existence of two floristic groups that had clear associations with either the Koppen's BSh (semi-arid) or Aw (seasonal tropical) climates. Likewise, the subdivisions of these groups showed clear associations with the dominant soil classes in the region. The Red-Yellow Latosol is the dominant soil classes in the BSh climatic domain, seconded by alluvial areas associated with Fluvic Neosols. The Aw domain comprised a much varied set of soils: Nitosols, Argisols, Cambisols and Litholic Neosols, most derived from the Bambuí limestone/slate formation. The ecotonal nature of northern Minas Gerais State provides a complex interaction between the flora of neighboring phytogeographical domains. This, allied to pedogeomorphological factors, allowed a better understanding of the effects of late Quaternary climate changes for the Deciduous Complex evolution. We conclude that the Latosols under present-day semi-arid climates (BSh) are relicts of former wetter climates, during which humid forest (semideciduous) expansion took place. Later, these semideciduous forests were subjected to a much drier climate, when selection for deciduousness led to the present-days Deciduous Complex scenario.

Reis Lake is located in the municipality of Caracaraí, state of Roraima (Brazil) and is subject to fluctuations in water level. The aim of this study was to analyze the structure of the phytoplankton community on the nictemeral and seasonal scales and determined the influence of limnological variables. Sampling was performed in the rainy season (June/2006) and dry season (November/2006), considering two nictemeral cycles. The phytoplankton community was assessed with regard to composition and density, abiotic variables were analyzed simultaneously. The lake had low concentrations of oxygen, clinograde profile and water stratified during the day and homogenous at night, with low concentrations of nutrients and waters ranging from slightly acidic to alkaline. The phytoplankton was represented by 43 taxa, 35 species in the dry season and 29 species in the rainy season. Low densities of phytoplankton occurred in both nictemeral cycles, with accentuated vertical gradient. The highest densities were recorded in the dry season. Reis Lake exhibits characteristics that classify it as a polymythic and oligotrophic environment. The variability in the data was more important seasonally than on the nictemeral scale, supporting the hypothesis of the influence of the hydrological cycle on the dynamics of phytoplankton communities in floodplain lakes.

The effects of copper toxicity on the photosynthetic activities of Avicennia germinans was investigated using two CuSO4 concentrations (0.062 and 0.33 M) added in Hoagland's solution in an aerated hydroponic system. Photosynthesis and chlorophyll fluorescence were measured after 30 h of copper stress. Results obtained in this study show that increasing levels of Cu+2 of 0.062 and 0.33 M Cu+2 resulted in a general reduction of the stomatal conductance (28 and 18%, respectively) and 100% of inhibition of net photosynthesis. Additionally, at these concentrations of Cu+2, reductions of chlorophyll fluorescence parameters were also observed. These changes suggested that the photosynthetic apparatus of Avicennia germinans was the primary target of the Cu+2 action. It is concluded that Cu+2 ions causes a drastic decline in photosynthetic gas exchange and Chlorophyll fluorescence parameters in A. germinans leaves.

The genus Lygodium Sw. is one of the few climbing ferns in the world. The spores of L. venustum Sw. and L. volubile Sw. were studied using light, scanning, and transmission electron microscopy. This work is based on herbarium material. The spores are trilete, triangular, with straight to convex sides in polar view. The equatorial diameter is 72-104 µm, and the polar diameter is 64-84 µm. The ornamentation in L. venustum is verrucate-tuberculate while in L. volubile, it is verrucate-tuberculate in the proximal face but with a few ridges on the distal face, where a micro-ornamentation constituted by verrrucae and tubercles is observed. An equatorial ridge is also present. The exospore is two-layered; in L. venustum, it is smooth in contrast with the ornamented exospore of L. volubile. The perispore of the two species analyzed is similar. This wall is four-layered with particular elements arranged radially in the middle layer. On the spores surface of both species, few spheroids are observed. The results introduced in the current study may be useful for the systematics of the genus as well as for phylogenetic purposes.

Three new species of the genus Ananteris Thorell have been discovered in Brazil. Ananteris desiderio sp. n., Ananteris camacan sp. n. and Ananteris infuscata sp. n. are respectively described from specimens collected in the regions of São Desidério, Camacã, Rebio UNA and Jequié in the state of Bahia, and Grão Mogol and Novo Horizonte in the state of Minas Gerais, Brazil. New records are also proposed for Ananteris luciae Lourenço, Ananteris mauryi Lourenço and Ananteris franckei Lourenço. The number of known Ananteris species known in the scorpion fauna of Brazil is now raised to 24.

Each animal species selects specific microhabitats for protection, foraging, or micro-climate. To understand the distribution patterns of small mammals on the ground and in the understorey, we investigated the use of microhabitats by small mammals in a deciduous forest of southern Brazil. Ten trap stations with seven capture points were used to sample the following microhabitats: liana, fallen log, ground litter, terrestrial ferns, simple-trunk tree, forked tree, and Piper sp. shrubs. Seven field phases were conducted, each for eight consecutive days, from September 2006 through January 2008. Four species of rodents (Akodon montensis, Sooretamys angouya, Oligoryzomys nigripes and Mus musculus) and two species of marsupials (Didelphis albiventris and Gracilinanus microtarsus) were captured. Captured species presented significant differences on their microhabitat use (ANOVA, p = 0.003), particularly between ground and understorey sites. Akodon montensis selected positively terrestrial ferns and trunks, S. angouya selected lianas, D. albiventris selected fallen trunks and Piper sp., and G. microtarsus choose tree trunks and lianas. We demonstrated that the local small-mammal assemblage does select microhabitats, with different types of associations between species and habitats. Besides, there is a strong evidence of habitat selection in order to diminish predation.