Nutritional reserves of Vochysiaceae seeds: chemical diversity and potential economic uses

Contents of proteins, carbohydrates and oil of seeds of 57 individuals of Vochysiaceae, involving one species of Callisthene, six of Qualea, one of Salvertia and eight of Vochysia were determined. The main nutritional reserves of Vochysiaceae seeds are proteins (20% in average) and oils (21. 6%). Mean of carbohydrate contents was 5. 8%. Callisthene showed the lowest protein content (16. 9%), while Q. cordata was the species with the highest content (30% in average). The contents of ethanol soluble carbohydrates were much higher than those of water soluble carbohydrates. Oil contents lay above 20% for most species (30. 4% in V. pygmaea and V. pyramidalis seeds). The predominant fatty acids are lauric (Q. grandiflora), oleic (Qualea and Salvertia) or acids with longer carbon chains (Salvertia and a group of Vochysia species). The distribution of Vochysiaceae fatty acids suggests for seeds of some species an exploitation as food sources (predominance of oleic acid), for other species an alternative to cocoa butter (high contents or predominance of stearic acid) or the production of lubricants, surfactants, detergents, cosmetics and plastic (predominance of acids with C20 or C22 chains) or biodiesel (predominance of monounsaturated acids). The possibility of exploitation of Vochysiaceae products in a cultivation regimen and in extractive reserves is discussed.

Hidden vorticity in binary Bose-Einstein condensates

We consider a binary Bose-Einstein condensate (BEC) described by a system of two-dimensional (2D) Gross-Pitaevskii equations with the harmonic-oscillator trapping potential. The intraspecies interactions are attractive, while the interaction between the species may have either sign. The same model applies to the copropagation of bimodal beams in photonic-crystal fibers. We consider a family of trapped hidden-vorticity (HV) modes in the form of bound states of two components with opposite vorticities S(1,2) = +/- 1, the total angular momentum being zero. A challenging problem is the stability of the HV modes. By means of a linear-stability analysis and direct simulations, stability domains are identified in a relevant parameter plane. In direct simulations, stable HV modes feature robustness against large perturbations, while unstable ones split into fragments whose number is identical to the azimuthal index of the fastest growing perturbation eigenmode. Conditions allowing for the creation of the HV modes in the experiment are discussed too. For comparison, a similar but simpler problem is studied in an analytical form, viz., the modulational instability of an HV state in a one-dimensional (1D) system with periodic boundary conditions (this system models a counterflow in a binary BEC mixture loaded into a toroidal trap or a bimodal optical beam coupled into a cylindrical shell). We demonstrate that the stabilization of the 1D HV modes is impossible, which stresses the significance of the stabilization of the HV modes in the 2D setting.

Bayesian online algorithms for learning in discrete Hidden Markov Models

We propose and analyze two different Bayesian online algorithms for learning in discrete Hidden Markov Models and compare their performance with the already known Baldi-Chauvin Algorithm. Using the Kullback-Leibler divergence as a measure of generalization we draw learning curves in simplified situations for these algorithms and compare their performances.

Mobilization of seed reserves during germination of four tropical species of the Amazon Rainforest

Seed reserve mobilization during germination of the Amazonian species Myciaria dubia (camu-camu), Eugenia stipitata(araca-boi), Dipteryx odorata (cumaru) and Hymenaea courbaril (jatoba) was evaluated. Seeds were placed in germination chambers at 30 degrees C with it 12 h photoperiod. Analysis of primary metabolites (carbohydrates, lipids and proteins) and fatty acid composition were carried out in quiescent seeds and at four germination stages after radicle protrusion. Germination was high in all species but there were statistically significant differences between species. Differences were also observed with regard to the duration of the germination period. The seeds showed variation in the content and composition of the analyzed compounds. indicating that the mobilization rates of these compounds may affect germination velocity.

The hidden diversity of Coleodactylus amazonicus (Sphaerodactylinae, Gekkota) revealed by molecular data

Coleodactylus amazonicus, a small leaf-litter diurnal gecko widely distributed in Amazon Basin has been, considered a single species with no significant morphological differences between populations along its range. A recent molecular study, however, detected large genetic differences between populations of central Amazonia and those in the easternmost part of the Amazon Basin, suggesting the presence of taxonomically unrecognised diversity. In this study, DNA sequences of three mitochondrial (165, cytb, and ND4) and two nuclear genes (RAG-1, c-mos) were used to investigate whether the species currently identified as C. amazonicus contains morphologically cryptic species lineages. The present phylogenetic analysis reveals further genetic subdivision including at least five potential species lineages, restricted to northeastern (lineage A), southeastern (lineage B), central-northern (lineage E) and central-southern (lineages C and D) parts of Amazon Basin. All clades are characterized by exclusive groups of alleles for both nuclear genes and highly divergent mitochondrial haplotype clades, with corrected pairwise net sequence divergence between sister lineages ranging from 9.1% to 20.7% for the entire mtDNA dataset. Results of this study suggest that the real diversity of ""C. amazonicus"" has been underestimated due to its apparent cryptic diversification. (C) 2009 Elsevier Inc. All rights reserved.

Physiological and biochemical characterization of the assai palm (Euterpe oleracea Mart.) during seed germination and seedling growth under aerobic and anaerobic conditions

Physiological and biochemical aspects of assai palm during seed germination and early seedling growth were investigated. Seeds collected from plants growing in flooded and upland forests were used to determine the influence of normoxic (aerobic) and anoxic (anaerobic) conditions in germination and the initial and average time of development in the roots and shoots. After 75 days, seedlings germinated under normoxia were transferred to trays and submitted to flooding. Seed reserves (lipids, proteins, soluble sugars and starch) were monitored for quiescent and germinated seeds maintained under normoxic and anoxic conditions, as well as after 5, 10 and 20 days of seedling growth. Alcohol dehydrogenase (ADH) activity was quantified in roots and leaves of seedlings without or with flooding (partial and total). Seeds were not able to germinate under anoxia. Different strategies of storage mobilization of lipids, proteins, soluble sugars and starch were observed in seeds of each environment. ADH activity was induced by anoxia, with the highest level observed in the leaves. This study showed that, under normoxic conditions, the best developmental performance of assai palm seeds, from flooded or upland forest areas, during germination was associated with primary metabolites mobilization and seedling flooding tolerance with increased ADH activity. We conclude that the assai palm is well adapted to the anoxic conditions provoked by flooding.

Fire management and the nesting of Athene cunicularia (Aves, Strigidae) in grasslands in central Cerrado, Brazil

Fire management is a common practice in several reserves in the Cerrado, but its influences on bird reproduction remain unknown. In addition, the nesting biology of the Burrowing Owl (Athene cunicularia) has been studied in numerous environments, but not in tropical grasslands managed by fire. This study examined the effects of fire management on the nesting biology of A. cunicularia in Emas National Park, State of Goias, central Brazilian Cerrado. We compared the number of breeding pairs and their burrows in October and November 2009 at 15 study sites in grasslands managed by fire (firebreaks) and unmanaged grasslands adjacent to and distant from firebreaks. We visited active burrows two-four times and described the burrow entrances and sentinel sites and counted and observed adults and young. A total of 19 burrows were found at firebreaks. One and two burrows were found in grasslands adjacent to and distant from firebreaks, respectively. For all burrows found, one to three young reached the adult size, being able to fly and/or run in early November. The 22 burrows found were in the ground, associated or not with termite and ant nests. Most (86.4%) burrows had only one entrance. Only three burrows had two or three entrances. Structures used as sentinel perches by adults were mounds in front of the burrow entrances, termite nests, shrubs and trees. Most of these sentinel sites were shorter than 2 m high and located less than 10 m from the burrow entrance. At Emas National Park, firebreaks appear to provide more attractive conditions to the nesting of A. cunicularia than unmanaged grasslands, likely because of the short herbaceous stratum due to frequent burning of firebreaks. This study suggests that fire management provides suitable conditions for the successful reproduction of A. cunicularia in firebreaks at Emas National Park.

Mudanças no Código Florestal e seu impacto na ecologia e diversidade dos mamíferos no Brasil

Os ecossistemas florestais do Brasil abrigam um dos mais altos níveis de diversidade de mamíferos da Terra, e boa parte dessa diversidade se encontra nas áreas legalmente protegidas em áreas de domínio privado. As reservas legais (RLs) e áreas de proteção permanente (APPs) representam estratégias importantes para a proteção e manutenção dessa diversidade. Mudanças propostas no Código Florestal certamente trarão efeitos irreversíveis para a diversidade de mamíferos no Brasil. Os mamíferos apresentam papéis-chave nos ecossistemas, atuando como polinizadores e dispersores de sementes. A extinção local de algumas espécies pode reduzir os serviços ecológicos nas RLs e APPs. Outra consequência grave da redução de áreas de vegetação nativa caso a mudança no Código Florestal seja aprovada será o aumento no risco de transmição de doenças, trazendo sério problemas a saúde pública no Brasil.

Trabalho e imigração: uma comparação Brasil-Argentina

O artigo busca discutir um novo padrão migratório da Bolívia para o Brasil e para a Argentina, especialmente vinculado à precarização do trabalho e à inserção desses imigrantes em formas de trabalho precário. Esse padrão & aparentemente novo em relação à integração dos contingentes migrantes ao longo do século XX & vem produzindo consequências que ainda estão por ser mapeadas. Uma delas é a presença de um contingente de bolivianos confinado ao setor de costura, trabalhando e vivendo em oficinas clandestinas, com pouca visibilidade pública, como face de uma precarização mundializada, resultante do assim chamado “custo chinês”. Resultante de um balanço bibliográfico e de uma incursão exploratória na pesquisa de campo tanto em São Paulo como em Buenos Aires, o artigo pretende apontar para aspectos específicos do fenômeno, combinando olhares e perspectivas que cruzam as dimensões migratórias, geracionais e de gênero.

Deficiência de vitamina A em pré-escolares da cidade do Recife, Nordeste do Brasil

RESUMO. O objetivo deste estudo foi avaliar a prevalência de deficiência de vitamina A (DVA) em pré-escolares da cidade do Recife, Nordeste Brasileiro. A amostra foi composta por 344 crianças, de 24 a 60 meses, de ambos os sexos, em 18 creches públicas da cidade do Recife, em 2007. O estado nutricional de vitamina A foi avaliado pelos indicadores bioquímico (retinol sérico) e dietético (inquérito de consumo alimentar) e o status pondo-estatural através dos índices antropométricos peso/idade (P/I), altura/idade (A/I) e peso/altura (P/A). A prevalência de níveis de retinol sérico baixos (<0,70μmol/L) foi de 7,7 por cento (IC 95 por cento 4,88 – 11,81), caracterizando a DVA como problema de saúde pública do tipo leve, segundo critérios da Organização Mundial de Saúde. Por outro lado, 29,6 por cento (IC 95 por cento 24,22 – 35,63) das crianças apresentaram níveis aceitáveis ou marginais (0,70 a 1,04μmol/L) de retinol. Em relação ao consumo de vitamina A, os valores abaixo da EAR (Estimated Average Requirement), de 210μg/dia para crianças de 24 a 47 meses e de 275μg/dia para crianças de 48 a 96 meses de idade foi de 8,1 por cento e 21,3 por cento, respectivamente. As prevalências de déficits antropométricos (<-2 escores –Z) nos pré-escolares foram de 2,5 por cento para o indicador P/I, de 8,6 por cento quanto ao A/I e de 1,5 por cento em relação ao P/A. Os dados acima evidenciam a importância da institucionalização para o adequado estado nutricional das crianças e manutenção dos estoques adequados de vitamina A. Todavia, são necessários mais estudos enfocando pré-escolares não institucionalizados, ou seja, crianças que vivem fora do ambiente privilegiado das creches

Diferenciais de cárie dentária entre os índios Xavante de Mato Grosso, Brasil

O objetivo do estudo foi avaliar níveis de experiência de cárie entre subgrupos Xavante que vivem em diferentes Terras Indígenas (T.I.) no Estado de Mato Grosso, Brasil, a fim de investigar a presença de desigualdades no interior de uma mesma etnia indígena. Os dados foram coletados através de um censo de saúde bucal realizados em 2004. Das sete T.I. Xavante existentes, foram investigadas quatro (Pimentel Barbosa, Sangradouro, Areões e Marechal Rondon), nas quais foram selecionadas a maior aldeia de cada. Foram adotados os critérios preconizados pela Organização Mundial da Saúde, e utilizado o índice CPOS. Para mensurar as diferenças entre as T.I. foi estimada a razão de prevalência (RP) por meio de análise de regressão de Poisson, efetuada na faixa etária entre 6 e 34 anos para cada sexo, incluindo a idade como covariável. Nesta faixa etária, as perdas variaram entre 26 a 30 por cento. Pimentel Barbosa foi considerada como referência para comparações por apresentar menor prevalência de cárie em todas as faixas etárias analisadas. A maior disparidade foi notada entre as T.I. Pimentel Barbosa e Sangradouro, tanto em homens (RP 2,68- IC95 por cento 2,41 a 2,97) como em mulheres (RP 2,03- IC95 por cento 1,85 a 2,23). A RP do componente obturado em Areões e Marechal Rondon (diferença relativa a Pimentel Barbosa) é muito pequena em relação à carga de doença total nestas T.I., indicando menor presença de serviço odontológico restaurador. Conclui-se que a transição em saúde bucal não é homogênea entre os Xavante e que as diferenças podem estar associadas a particularidades do processo histórico de interação com a sociedade não-indígena (Continua) (Continuação) Determinantes locais e regionais, incluindo fatores demográficos, características econômicas e sócio-culturais específicas, acesso e utilização de serviços de saúde, podem ter determinado as desigualdades de ataque de cárie observadas entre os Xavante

Bee communities (Hymenoptera: Anthophila) of the "Cerrado" ecosystem in Sao Paulo State, Brazil

Five surveys of the bee communities in four "Cerrado" ecosystem reserves in Sao Paulo State were compared for species richness and similarity. These areas are fragment vegetation reser-reserves located in the Cerrado Corumbata Reserve (Corumbata), Jata Ecological Park (Luiz Antonio), Cajuru (Cajuru), and Vassununga State Park - ""Gleba de Cerrado de Pe-de-Gigante"" (Santa Rita do Passa Quatro). The methodology consisted of capturing bees foraging on flowers along transects, though with small differences between surveys. These ""cerrado"" areas have a large number of species of native bees, which are important pollinators in several Brazilian ecosystems. The community of bees varied among these different fragments. Based on 500 individuals (standardized by rarefaction), Cajuru, Corumbata 1 and Corumbata 2 were the areas with highest species richness, and Jata and Pe-de-Gigante had the lowest species richness in the bee communities. The bee faunas of Corumbata 2 and Pe-de-Gigante had the highest similarity, forming a group with the bee fauna of Cajuru. The bee faunas of Corumbata 1 and Jata were isolated from this group. We found that the bee species richness and similarity found in these ""cerrado"" areas cannot be explained by general factors such as the size of the fragment, the species richness of plants and the distance between the areas. Therefore, we suppose that local factors that differ among areas, such as interactions between populations, and competition and interference from surrounding areas influence and determine bee species richness and similarity in these reserves.

Allosteric Control of Gating Mechanisms Revisited: The Large Conductance Ca(2+)-Activated K(+) Channel

Large-conductance Ca(2+)-activated K(+) channels (BK) play a fundamental role in modulating membrane potential in many cell types. The gating of BK channels and its modulation by Ca(2+) and voltage has been the subject of intensive research over almost three decades, yielding several of the most complicated kinetic mechanisms ever proposed. A large number of open and closed states disposed, respectively, in two planes, named tiers, characterize these mechanisms. Transitions between states in the same plane are cooperative and modulated by Ca(2+). Transitions across planes are highly concerted and voltage-dependent. Here we reexamine the validity of the two-tiered hypothesis by restricting attention to the modulation by Ca(2+). Large single channel data sets at five Ca(2+) concentrations were simultaneously analyzed from a Bayesian perspective by using hidden Markov models and Markov-chain Monte Carlo stochastic integration techniques. Our results support a dramatic reduction in model complexity, favoring a simple mechanism derived from the Monod-Wyman-Changeux allosteric model for homotetramers, able to explain the Ca(2+) modulation of the gating process. This model differs from the standard Monod-Wyman-Changeux scheme in that one distinguishes when two Ca(2+) ions are bound to adjacent or diagonal subunits of the tetramer.

The first record on Brazilian stingless bees published 450 years ago by Hans Staden

Only a few decades after 1492, when Christopher Columbus arrived on a Caribbean island and Pedro Alvares Cabral claimed Brazil for Portugal in 1500, a German mercenary gave the first description of stingless bees in 1557. He got to know them when he was imprisoned for months by an anthropophagous tribe in the coastal region of Santos, today in the State of Sao Paulo. This rather short but nevertheless extremely exact record on stingless bees is hidden in the first book on Brazil. Three species and important aspects of their life history were treated. This early description has been completely overlooked by bee scientists until now. My note intends to close this evident gap.

An insight into the sialotranscriptome of the brown dog tick, Rhipicephalus sanguineus

Background: Rhipicephalus sanguineus, known as the brown dog tick, is a common ectoparasite of domestic dogs and can be found worldwide. R. sanguineus is recognized as the primary vector of the etiological agent of canine monocytic ehrlichiosis and canine babesiosis. Here we present the first description of a R. sanguineus salivary gland transcriptome by the production and analysis of 2,034 expressed sequence tags (EST) from two cDNA libraries, one consctructed using mRNA from dissected salivary glands from female ticks fed for 3-5 days (early to mid library, RsSGL1) and the another from ticks fed for 5 days (mid library, RsSGL2), identifying 1,024 clusters of related sequences. Results: Based on sequence similarities to nine different databases, we identified transcripts of genes that were further categorized according to function. The category of putative housekeeping genes contained similar to 56% of the sequences and had on average 2.49 ESTs per cluster, the secreted protein category contained 26.6% of the ESTs and had 2.47 EST's/clusters, while 15.3% of the ESTs, mostly singletons, were not classifiable, and were annotated as ""unknown function"". The secreted category included genes that coded for lipocalins, proteases inhibitors, disintegrins, metalloproteases, immunomodulatory and antiinflammatory proteins, as Evasins and Da-p36, as well as basic-tail and 18.3 kDa proteins, cement proteins, mucins, defensins and antimicrobial peptides. Comparison of the abundance of ESTs from similar contigs of the two salivary gland cDNA libraries allowed the identification of differentially expressed genes, such as genes coding for Evasins and a thrombin inhibitor, which were over expressed in the RsSGL1 (early to mid library) versus RsSGL2 (mid library), indicating their role in inhibition of inflammation at the tick feeding site from the very beginning of the blood meal. Conversely, sequences related to cement (64P), which function has been correlated with tick attachment, was largely expressed in the mid library. Conclusions: Our survey provided an insight into the R. sanguineus sialotranscriptome, which can assist the discovery of new targets for anti-tick vaccines, as well as help to identify pharmacologically active proteins.