232 research outputs found

    Assessing the soil physical characteristics of the gallery woods area at the hydrographic Mariana sub-catchment for environmental conservation

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    [Abstract] The objective of this work was to characterize soil physical properties of the gallery woods area at the hydrographic Mariana sub-catchment. The physical attributes evaluated were: bulk density, gravimetric humidity, soil porosity and mechanical resistance to penetration. The field work was carried out at Alta Floresta-MT, Brazil. Nine plots of 20 m x 50 m in surface were marked along the upper and middle river course areas in such a way that they were representative of all the subcatchment extension. The experimental design was completely randomized. Soil density of the gallery woods area was higher than that of the native forest, so that development of the root system of the trees even could be restricted. Gravimetric humidity was found to be homogeneous when different areas or different depths were compared. Soil porosity was found to be adequate for native gallery woods. Mean penetration resistance at the 0-0.25 m depth was classified as moderate, bout hint the upper and middle river course areas

    Working-class royalty: bees beat the caste system

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    The struggle among social classes or castes is well known in humans. Here, we show that caste inequality similarly affects societies of ants, bees and wasps, where castes are morphologically distinct and workers have greatly reduced reproductive potential compared with queens. In social insects, an individual normally has no control over its own fate, whether queen or worker, as this is socially determined during rearing. Here, for the first time, we quantify a strategy for overcoming social control. In the stingless bee Schwarziana quadripunctata, some individuals reared in worker cells avoid a worker fate by developing into fully functional dwarf queens

    Composição E Diversidade De Anuros Na Restinga Do Município De Conde, Litoral Norte Do Estado Da Bahia, Nordeste Do Brasil

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    The Conde municipality is located in the northern coast of the state of Bahia (NC), northeastern Brazil, and is part of the Atlantic Tropical domain. The anuran fauna of the northern portion of the NC is still poorly known if compared to the southern portion. The Restinga is one of the predominant environments of the coastal plains of the NC and it is characterized essentially by presenting sandy soil covered by herbaceous and shrubby vegetation. The objective of this study was to determine the anuran species composition and diversity for the Restinga of the Conde municipality. Sampling was carried out at night by active search over four periods of five consecutive days each, two over the ‘main rainy season’ and two in a ‘lesser rainy season’, using 14 sample units (SUs) and five extra sample plots (EPs). We calculated dominance and species diversity using the Berger-Parker and Shannon-Wiener H’ indices, respectively. We used accumulation curves and the Jackknife 1 estimator to estimate anuran species richness, considering only the data obtained from the SUs. We recorded 713 anuran specimens distributed within 33 species, 13 genera and five families (Bufonidae, Craugastoridae, Hylidae, Leptodactylidae and Microhylidae). The Hylidae and Leptodactylidae families had the highest species richness. Considering only the SUs (Jackknife 1 estimator in brackets), we recorded 28 species in the study area (33.9 ± 2.3), 13 in Shrubby Vegetation Zones-SVZ (20.8 ± 2.9) and 25 in Freshwater Wetland Zones-FWZ (28.9 ± 1.9). The abundance and species diversity of the FWZ (n = 638 specimens; H’= 2.4) were higher than those recorded for the SVZ (n = 52 specimens; H’ = 1.9). The SVZ and FWZ showed distinct dominant species, wherein Pristimantis paulodutrai was the dominant species in SVZ and Scinax fuscomarginatus in FWZ. The Restinga of the Conde municipality stands out as the one with the highest anuran species richness already recorded considering only SVZ and FWZ. Moreover, its anuran species composition represented 55% of the anuran species known for the NC and included taxa common to three different morphoclimatic domains (Tropical Atlantic, Cerrado and Caatinga). © 2016, Universidade Estadual de Campinas UNICAMP. All rights reserved.16

    Pickering emulsions stabilized with curcumin-based solid dispersion particles as mayonnaise-like food sauce alternatives

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    Pickering emulsions, which are emulsions stabilized by colloidal particles, are being increasingly positioned as novel strategies to develop innovative food product solutions. In this context, the present work aims to develop Pickering emulsions stabilized by natural-based curcuminloaded particles produced by the solid dispersion technique as promising mayonnaise-like food sauce alternatives. Two particle formulations (KC1 and KC2) were produced using k-carrageenan as the matrix material and different curcumin contents, then employed in the preparation of three Pickering emulsion formulations comprising different oil fractions (') and particle concentrations (KC1 ' 0.4 (4.7%), KC2 ' 0.4 (4.7%) and KC2 ' 0.6 (4.0%)). The creaming index tests accompanied by the optical microscopy analysis evidenced the good stability of the developed products for the tested period of 28 days. The final products were tested concerning color attributes, pH, oxidative stability, textural, and nutritional composition, and compared with two commercial mayonnaises (traditional and light products). Overall, the produced emulsions were characterized by a bright yellow color (an appealing attribute for consumers), an acidic pH (similar to mayonnaise), and a considerably improved oxidative stability, implying a foreseeable longer shelf life. The sauce KC1 ' 0.4 (4.7%) showed a similar texture to the light commercial mayonnaise, being a promising alternative to conventional sauces, holding a low-fat content and potentially added benefits due to the curcumin and virgin olive oil intrinsic properties.The authors are grateful to the Foundation for Science and Technology (FCT, Portugal) and FEDER under Programme PT2020 for financial support to CIMO (UIDB/00690/2020) and LSRE-LCM (UIDB/50020/2020). Promove program of the “la Caixa” Foundation and BPI. National funding by FCT, P.I., through the institutional scientific employment program-contract for Arantzazu Santamaria-Echart, Nuno Rodrigues, Márcio Carocho, and Lillian Barros. FCT for the Research grant SFRH/BD/147326/2019 of Stephany C. de Rezende.info:eu-repo/semantics/publishedVersio
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