Decontamination and deodorization of 2,4,6-trichloroanisole on cork

The presence of 2,4,6-trichloroanisole (2,4,6-TCA) in cork was identified as a problem for the cork industry in the early 80’s and also considered as a potent compound towards the origin of organoleptic defects in wines. These defects are easily detected by the consumers and it only takes as little as about 5 ng/L to be detected. However, there is a certain difficulty when trying to detect such low concentration levels with mass spectrometry. Heavily contaminating the cork substrates with TCA could be a solution for this detection limitation. By artificially contaminating the samples and by using quadrupole mass spectrometry (QMS) coupled with temperature-programmed desorption (TPD), we verified the presence of a TCA desorption peak in a cork substrate. We also verified that heating above a temperature of 160ºC in a high vacuum atmosphere allows the removal of this contaminant from cork substrates. A TCA quantification method that was developed with this work confirmed that the majority of the TCA was removed with the TPD experiment when heating above the TPD peak. The main outcome of this experiment is the proposed process to remove TCA from cork stoppers by heating at temperatures close or above the TPD peak. Such process would have the goal of making cork and its derivative products free of TCA, or at least below the human detection threshold. In order to achieve this goal, it is necessary to understand how the TCA adsorption occurs, and that will be the objective and the contribution of this thesis work - to confirm the nature of the TCA adsorption and, most importantly, an attempt to determine which group of its molecule is effectively adsorbing onto the cork substrates. For this purpose, other substrates and compounds were chosen to be experimented due to their similarities with the constitution of cork constitution and the chemical structure of TCA, respectively. This experiment showed that cellulose does not have a relevant role in the adsorption process

The influence of habitat and species attributes on the density and nest spacing of a stingless bee (Meliponini) in the Atlantic Rainforest.

T. spinipes lives in perennial eusocial colonies and builds nests exposed on tree branches. Why this habitat generalist with exposed nests cannot nest successfully in forest habitats is intriguing. This study explores the hypothesis this species reaches higher densities in vegetation with open canopies and the subsidiary shading hypothesis, assuming the failure of exposed nests in closed canopy rainforest. As this species shows the basic attributes of territorial foraging groups, the hypothesis of uniform nest spacing is also tested. Comparative field data on nest density and spacing in open canopy vegetation and adjacent closed canopy forest are used to test these hypotheses. In random 40 20x200m plots in rubber groves, 18 nests were recorded. This nest density for a single stingless bee was approximately 36 times higher than in the adjacent rainforest. The high density of nests in the rubber groves is also associated with a regular spatial distribution of nests. The ostensive patrolling distances from the colonies probably operates at short distances, which still corresponds to large territorial areas for such a small stingless bee.We conclude that: this species faces powerful nesting constraints in the ever green and closed canopy of rainforest habitats; as the nest density approaches the density threshold, the patrolling mechanism regulates access to prospective nest sites; the high availability of sunny sites for nesting within the deciduous and open canopy of rubber trees favours the high nest density of T. spinipes and its wide spread distribution where this agroforestry system dominates.

Tree species used for nesting by stingless bees (Hymenoptera: Apidae: Meliponini) in the Atlantic Rain Forest (Brazil): Availability or Selectivity

The stingless bees (Meliponini) are numerically dominant in tropical forests and most species depend on preexisting cavities for nesting, mainly tree hollows. However, it is still incipient the knowledge about basic characteristics of forest trees used for nesting. The basic questions addressed in this study include: would appropriate hollows be restricted to a few tree species? Would there be selectivity in the use of tree hollows in the forest? These issues are addressed from the comparison of usage patterns among forest trees in different stages of forest regeneration in the Atlantic Forest (Michelin Reserve in northeastern Brazil). Among 89 nests (from six species) found in tree hollows, in a sampled area of 32 ha of forests, 78.7% were associated with live plants and 21.3% to dead trees. This result does not support the hypothesis of selectivity for living trees, considering the high rate of living trees: dead trees (40:1). Nests were sampled from 41 tree species of 31 genera and 22 plant families. Meliponini species showed no differential association with any tree species. The absence of selectivity of tree species as nesting site is probably due to the high diversity of trees per hectare of Atlantic rainforest. The stingless bees also showed no selectivity for wood hardness, therefore the potential durability of tree hollows probably exerts weak selective pressure on bees, or at least the hardness variation range of trees used for nesting has no important influence on reproductive success of the colonies of stingless bees

Pollinator Sharing in Specialized Bee Pollination Systems: a Test with the Synchronopatric Lip Flowers of Centrosema Benth (Fabaceae)

Bee-pollinated lip flowers of two synchronopatric species of Centrosema were used as models to examine the influence of specialized pollination systems on the ecological mechanisms of pollinator sharing. Regression analysis of bee abundances in the habitat on bee abundances on C. pubescens flowers was significant (r = 0.69; P = 0.001) and became very consistent and highly significant (r = 0.87; P = 0.00001) using a size threshold of bee pollinators longer than 15mm. These same relationships were not significant (P > 0.01), however, for C. brasilianum flowers. The structures of the two pollination systems also sustained the hypothesis of a size threshold for pollinators, although only the C. pubescens-bees interactions sustained the hypothesis of random interactions proportional to species abundances in the habitat. The flower visitor pools of the two plant species shared the same four main bee guilds: the pollinators Centridini, Xylocopa, and Euglossini and the primary nectar robber Oxaea. However, a significant divergence (P < 0.01) was detected between the two systems when the abundances and behaviors (pollinators or cheaters) of the main shared flower visitors were incorporated into the overall quantitative analysis (NMDS). The flowers size differences are not significant (P > 0.05) and could not explain these divergences. Particularly, the concentrations of the largest pollinators Eulaema and Xylocopa on C. pubescens flowers and the behavior shift of Centridini bees that act as legitimate pollinators in C. pubescens and as nectar robbers in C. brasilianum are better understood as functional foraging responses triggered by the synchronopatry and by nectar volume differences (P = 0.001) between both lip flowers. Paradoxically, the robbery activity of Centridini bees arises as a supply side effect of smaller nectar volume in C. brasilianum flowers

Annual survival rate of tropical stingless bee colonies (Meliponini): variation among habitats at the landscape scale in the Brazilian Atlantic Forest

Stingless social bees live in perennial colonies whose longevity is influenced by various ecological factors. This study analyzed the influence of habitat anthropization and native forest regeneration stage on the longevity of natural colonies at the landscape scale. Random sampling of 25x25m plots, totaling 30ha per habitat type, located and monitored 118 nests of 14 species in the forest and 105 nests of six species in the anthropic habitat. Significant differences in colony longevity were observed between young and long-lived forests  and between long-lived forests and anthropized habitat. Shorter longevities have generally been associated with a set of smaller-bodied species residing in anthropized habitats. The greatest longevities were associated with the three abundant and exclusive forest species, and was similar in the two forest regeneration stages: Melipona scutellaris, Scaptotrigona xanthotricha and Scaptotrigona bipunctata had high annual survival rates ranging from 87% to 93%. Another abundant species in the landscape was Tetragonisca angustula, a small habitat-generalist with short longevity (63%) that varied among habitats. Euclidean distance analysis based on this generalist placed young forest closest to anthropic habitat, and grouped the replicates of long-lived forest. Considering spatial variation in the life history traits, we infer that, among prospective landscape habitats, the Atlantic Forest favors stingless bees with high colonial longevity. On the other hand, generalists, such as T. angustula, with shorter colonial longevity and high reproduction rates are being favored by the expansion of anthropized habitats in place of deforested areas

Flora oleífera e sua guilda de abelhas em uma comunidade de restinga tropical

Centridini is a very diversified oilbee group in the open vegetation habitats of coastal restinga, where it represents 20% of all bee species and 50% of bee individuals sampled on melittophilous flowers. This oilbee guild is packed in Byrsonima sericea (Malpighiaceae) flowers, its single oil source in this plant community. B. sericea is a self-incompatible species that relies mainly on Centridini bees for cross-pollination, therefore, the high population density of B. sericea (65 indiv/ha) in the restinga might be related with the high local abundance of Centridini bees and vice-versa. This statement is indirectly supported by the positive relationship between diversity measures of Centridini and Malpighiaceae in the surrounding lowlands. Anyway, to explain the high diversity of Centridini in the restinga, the abundance of oilflowers might be more important than richness of oilflowers. These rich oil patches release population growth of the Centridini bees, and they should play a central role for planning in situ biological conservation in the patchy restinga landscape.As abelhas Centridini destacam-se na comunidade de abelhas da restinga arbustivo-arbórea, onde somam 20% das espécies e 50% dos indivíduos. As 17 espécies dessa guilda de coletores de óleos concentram-se especialmente nas flores de Byrsonima sericea D.C. (Malpighiaceae), a única fonte local de óleos florais. B. sericea é auto-incompatível e depende de Centridini para polinização cruzada, por isso, a abundância dessas abelhas parece estreitamente relacionada à densidade local excepcionalmente elevada desta fonte de óleo (65 indiv/ha) e vice-versa. Este argumento é apoiado, indiretamente, pela correlação positiva entre as diversidades alfa de Centridini e de Malpighiaceae nesta faixa tropical. Em aparente contradição, a abundância de óleos florais oferece explicação mais satisfatória para a diversidade excepcionalmente elevada de Centridini na restinga, do que a riqueza local da flora oleífera. Ricos em óleos florais, os hábitats de restinga arbustiva-arbórea funcionam como centro de expansão populacional de Centridini e, por isso, têm papel central na conservação biológica in situ

Permeability of matrices of agricultural crops to Euglossina bees (Hymenoptera, Apidae) in the Atlantic Rain Forest

International audienceAbstractWe evaluate the permeability of three matrices of arboreal crops for the Euglossina bees that inhabit the Brazilian Atlantic rainforest hotspot. The comparisons of occurrences and abundances within three mosaics of forest and extensive arboreal crops (piassava palm, oil palm, and rubber tree) showed that all the matrices were permeable to most orchid bees. The piassava palm was the most permeable, where the spatial distribution of all species of Euglossina did not differ between forest fragments and matrix. The oil palm has shown some loss of permeability to Eulaema atleticana, while the rubber tree crop was not so permeable to El. atleticana and Euglossa imperialis. Euglossa iopoecila was sampled only in the forest fragments. At the present scale of forest cover in the three studied mosaics (10 to 40 %), the arboreal matrices are contributing towards the functional connectivity in the Atlantic Rain Forest at both scales: the landscape mosaic and the Brazilian Atlantic Forest corridor

“Deixa Ela Falar”: Uma Análise Semiolinguística de uma Obra Literária com Capa de Meme Genuinamente Brasileiro

O presente trabalho propõe-se a analisar uma publicação da página do Facebook “Obras literárias com capas de memes genuinamente brasileiros”, cujo objetivo era chamar a atenção do destinatário para a quantidade de vezes em que a pré-candidata à presidência da república, Manuela D’Ávila, foi interrompida por outros indivíduos, ao participar do programa Roda Viva, da TV Cultura. Para tal, recorreu-se ao livro “Garota Interrompida”, deslocando o sentido deste último vocábulo, criando o que Charaudeau (2005) chama de novo Processo de Semiotização do Mundo, pois se substituiu a ilustração da capa do livro por uma foto de Manuela, sentada nos estúdios do referido programa. Além disso, recorrer-se-á à noção de imaginário sócio-discursivo(2013), cunhada pelo teórico em questão, para explicar a crença de que mulheres podem ter suas falas interrompidas. Assim, tal página foi capaz de denunciar o machismo sofrido pela deputada, ao criticar todos que tentaram subjugá-la, dizendo, indiretamente, “deixa ela falar”.O presente trabalho propõe-se a analisar uma publicação da página do Facebook “Obras literárias com capas de memes genuinamente brasileiros”, cujo objetivo era chamar a atenção do destinatário para a quantidade de vezes em que a pré-candidata à presidência da república, Manuela D’Ávila, foi interrompida por outros indivíduos, ao participar do programa Roda Viva, da TV Cultura. Para tal, recorreu-se ao livro “Garota Interrompida”, deslocando o sentido deste último vocábulo, criando o que Charaudeau (2005) chama de novo Processo de Semiotização do Mundo, pois se substituiu a ilustração da capa do livro por uma foto de Manuela, sentada nos estúdios do referido programa. Além disso, recorrer-se-á à noção de imaginário sócio-discursivo(2013), cunhada pelo teórico em questão, para explicar a crença de que mulheres podem ter suas falas interrompidas. Assim, tal página foi capaz de denunciar o machismo sofrido pela deputada, ao criticar todos que tentaram subjugá-la, dizendo, indiretamente, “deixa ela falar”

Testemunhos de fieis publicados pela Igreja Universal do Reino de Deus no jornal Folha Universal: uma análise exploratória

The aim of the present study is to identify profiles of testimonies published in the newspaper column "Miracles of Faith" from the "Folha Universal" - Igreja Universal do Reino de Deus (IURD). We used content analysis, the survey methodology and the method Grade of Membership (GoM) to identify profiles. We obtained two well defined profiles of witnesses and a third, with lower prevalence. The most prevalent profile was associated with women who participated in campaigns promoted by the church, which sought IURD due to health problems. The second most prevalent was associated with higher probability of testimonies of homosexual men and/or with emotional problems. The results should be analyzed with caution since the testimonies are pre-screened before being published, given the fact that the testimony could attract more believers.Igreja Universal do Reino de Deus, religion, demography, Grade of Membership method