630 research outputs found

    Determinação de conteúdo de terebintina em diferentes espécies de Pinus spp. e estações do ano.

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    Várias espécies de Pinus têm sido utilizadas para a extração de resina, a qual é empregada como base para a produção de diversos produtos industriais. O objetivo foi estimar o conteúdo de terebintina das principais espécies de pínus com maior potencial para a produção de resina. Para o seguinte trabalho analisou-se a resina extraída de cinco espécies e de um híbrido de Pinus, P. elliottii, P. caribaea var. hondurensis, P. caribaea var. bahamensis, P. caribaea var. caribaea, e o híbrido entre P. elliottii e P. caribaea var. hondurensis. As resinas foram coletadas por um período de 24 horas e armazenadas em saco plástico sob refrigeração. O conteúdo de terebintina foi obtido pelo método de evaporação. A proporção de terebintina, que é volátil sob temperaturas entre 170 °C e 200 °C, foi obtida por meio da diferença de massa antes e depois da secagem em estufa. A partir das proporções de breu e terebintina, analisou-se quais espécies possuem maior produção de terebintina, componente que possui alto valor agregado no mercado. Com os resultados, foi possível observar que a espécie P. elliottiiapresenta uma das maiores porcentagens de produção de terebintina, variando entre 25% a 45% do total evaporado, tendo como subsequentes as espécies P. caribaea var. hondurensis, P. caribaea var. bahamensis, e o híbrido (P. elliottii x P. caribaea var. hondurensis) com porcentagens acima de 25% da produção de terebintina. Foi possível também comparar a relação de produção de terebintina entre estações: primavera, verão e outono. Notou-se que P. elliottii tem maior produção no outono e menor na primavera, mas, mesmo assim, se mantém como a espécie com a maior produção de resina entre as estações, atingindo uma porcentagem de 54% em relação às demais espécies. A segunda melhor espécie produtora de resina foi P. caribaea var. hondurensis que apresentou produção de 18% entre as estações, tendo maior produção no outono e verão, e menor produção na primavera. Os resultados deste trabalho contribuirão para a seleção de genótipos e espécies com maior produção de terebintina, assim como indicará se há estações mais propícias para a extração de resina

    The Growth of Eimeria tenella: Characterization and Application of Quantitative Methods to Assess Sporozoite Invasion and Endogenous Development in Cell Culture

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    In vitro development of the complete life cycle of Eimeria species has been achieved in primary cultures of avian epithelial cells with low efficiency. The use of immortalized cell lines simplifies procedures but only allows partial development through one round of parasite invasion and intracellular replication. We have assessed the suitability of Madin-Darby Bovine Kidney (MDBK) cells to support qualitative and quantitative studies on sporozoite invasion and intracellular development of Eimeria tenella. Analysis of parasite ultrastructure by transmission electron microscopy and serial block face—scanning electron microscopy proved the suitability of the system to generate good quality schizonts and first-generation merozoites. Parasite protein expression profiles elucidated by mass spectrometry corroborated previous findings occurring during the development of the parasite such as the presence of alternative types of surface antigen at different stages and increased abundance of proteins from secretory organelles during invasion and endogenous development. Quantitative PCR (qPCR) allowed the tracking of development by detecting DNA division, whereas reverse transcription qPCR of sporozoite- and merozoite-specific genes could detect early changes before cell division and after merozoite formation, respectively. These results correlated with the analysis of development using ImageJ semi-automated image analysis of fluorescent parasites, demonstrating the suitability and reproducibility of the MDBK culture system. This systems also allowed the evaluation of the effects on invasion and development when sporozoites were pre-incubated with anticoccidial drugs, showing similar effects to those reported before. We have described through this study a series of methods and assays for the further application of this in vitro culture model to more complex studies of Eimeria including basic research on parasite cell biology and host-parasite interactions and for screening anticoccidial drugs

    Density and distribution of Xylocopa nests (Hymenoptera: Apidae) in Caatinga areas in the surroundings of Passion fruit crops.

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    Due to their importance as pollinators of many plant species, this study aimed to know the nest density, spatial distribution, and nesting substrates used by Xylocopa species in the Caatinga, a xerophilous vegetation f Northeastern Brazil. Three areas of Caatinga in the surroundings of passion fruit crops were sampled. The bee species found in these areas were Xylocopa grisescens Lepeletier and Xylocopa frontalis (Olivier). All nests were in Commiphora leptophloeos (Burseraceae) trees (n=113). Phytosociological analysis showed that this tree species presented the highest absolute density (212.5 individuals/ha) and index of importance value (52.7). The distribution pattern of the C. leptophloeos was aggregated. The nests were located in dead and dried branches with an average diameter of 5.3±2.0 cm (n=43). The mean number of nests/tree was 3.1± 2.8 (n=113). The less disturbed area showed 6.7 nests/ha and 4.2 nests/tree. In the disturbed areas, 0.9 nests/ha and 2.4 to 2.7 nests/tree were observed. The availability of substrate for nesting in the studied areas and its importance as a limiting factor for nesting are discusse

    In vitro Anticoccidial Study of Oregano and Garlic Essential Oils and Effects on Growth Performance, Fecal Oocyst Output, and Intestinal Microbiota in vivo

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    This study investigated the in vitro effects of Greek oregano and garlic essential oils on inhibition of Eimeria parasites and their in vivo effects on production performance, intestinal bacteria counts, and oocyst output. An inhibition assay was performed in vitro using Eimeria tenella Wisconsin strain sporozoites and Madin-Darby bovine kidney (MDBK) cells. Intracellular sporozoite invasion was quantified by detection of E. tenella DNA using qPCR from cell monolayers harvested at 2 and 24 h post-infection. Parasite invasion was inhibited by the oregano essential oil at the concentration of 100 μg/ml by 83 or 93% after 2 or 24 h, respectively. Garlic essential oil reached a maximum inhibition of 70% after 24 h with the 50 μg/ml concentration. Normal morphology was observed in MDBK cells exposed to concentrations of 100 μl/ml of garlic or oregano for over 24 h. In the in vivo trial, 180 male broiler chicks (45.3 ± 0.7 g) were allocated into two treatments (6 pens of 15 chicks per treatment). Control treatment was fed commercial diets without antibiotics or anticoccidials. The ORE–GAR treatment was fed the same control diets, further supplemented with a premix (1 g/kg feed) containing the oregano (50 g/kg premix) and garlic (5 g/kg premix) essential oils. At day 37, all birds were slaughtered under commercial conditions, and intestinal samples were collected. ORE-GAR treatment had improved final body weight (1833.9 vs. 1.685.9 g; p < 0.01), improved feed conversion ratio (1.489 vs. 1.569; p < 0.01), and reduced fecal oocyst excretion (day 28: 3.672 vs. 3.989 log oocysts/g, p < 0.01; day 37: 3.475 vs. 4.007 log oocysts/g, p < 0.001). In the caecal digesta, ORE-GAR treatment had lower total anaerobe counts (8.216 vs. 8.824 CFU/g; p < 0.01), whereas in the jejunum digesta the ORE-GAR treatment had higher counts of E. coli (5.030 vs. 3.530 CFU/g; p = 0.01) and Enterobacteriaceae (5.341 vs. 3.829 CFU/g; p < 0.01), and lower counts of Clostridium perfringens (2.555 vs. 2.882 CFU/g; p < 0.01). In conclusion, the combined supplementation of oregano and garlic essential oils had a potent anticoccidial effect in vitro and a growth-promoting effect in broilers reared in the absence of anticoccidial drugs

    Economic evaluation of conservation through use of an Araucaria angustifolia provenance and progeny test.

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    Araucaria angustifolia is a species known for its valuable wood and nuts, but it is threatened with extinction. The plantation of forests for genetic resource conservation is a complementary strategy designed to reduce the species’ genetic variability loss. This study aimed to evaluate the technical and economic viability of A. angustifolia for genetic conservation through use. The analyzed provenance and progeny trial was established in 1982 in Itapeva, Brazil. It was structured using a compact family blocks design with 110 open-pollinated progenies from five natural populations, three replicates, ten plants per subplot, and 3.0 m × 2.0 m spacing. After 33 years, the trial was evaluated for total height, diameter at breast height, wood volume, and survival. The variance components and genetic parameter estimates were performed using Restricted Maximum Likelihood/Best Linear Unbiased Prediction methods (REML/BLUP) methods with the Selegen software (version 2014). The production and management scenarios were obtained using the SisAraucaria software (version 2003). Sensitivity analysis and economic parameter estimates were obtained through various economic evaluation methods using the Planin software (version 1995). In general, the genetic parameters indicated that the population has enough variability for both conservation and breeding purposes, suggesting technical viability for the establishment of a seed orchard. The economic parameters indicated that the commercialization of wood and araucaria nuts proved to be more profitable than wood production by itself. In conclusion, araucaria genetic conservation through use is a technically and economically viable ex situ conservation strategy

    A scoring tool to predict mortality and dependency after cerebral venous thrombosis

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    Abstract Background and purpose: A prognostic score was developed to predict dependency and death after cerebral venous thrombosis (CVT) to identify patients for targeted therapy in future clinical trials. Methods: Data from the International CVT Consortium were used. Patients with pre- existent functional dependency were excluded. Logistic regression was used to predict poor outcome (modified Rankin Scale score 3– 6) at 6 months and Cox regression to predict 30- day and 1- year all- cause mortality. Potential predictors derived from previous studies were selected with backward stepwise selection. Coefficients were shrunk using ridge regression to adjust for optimism in internal validation. Results: Of 1454 patients with CVT, the cumulative number of deaths was 44 (3%) and 70 (5%) for 30 days and 1 year, respectively. Of 1126 patients evaluated regarding functional outcome, 137 (12%) were dependent or dead at 6 months. From the retained predictors for both models, the SI2NCAL2C score was derived utilizing the following components: absence of female- sex- specific risk factor, intracerebral hemorrhage, infection of the central nervous system, neurological focal deficits, coma, age, lower level of hemoglobin (g/l), higher level of glucose (mmol/l) at admission, and cancer. C- statistics were 0.80 (95% confidence interval [CI] 0.75– 0.84), 0.84 (95% CI 0.80– 0.88) and 0.84 (95% CI 0.80– 0.88) for the poor outcome, 30- day and 1- year mortality model, respectively. Calibration plots indicated a good model fit between predicted and observed values. The SI2NCAL2C score calculator is freely available at www.cereb ralve noust hromb osis.com. Conclusions: The SI2NCAL2C score shows adequate performance for estimating individual risk of mortality and dependency after CVT but external validation of the score is warranted

    Study of Bc+B_c^+ decays to the K+Kπ+K^+K^-\pi^+ final state and evidence for the decay Bc+χc0π+B_c^+\to\chi_{c0}\pi^+

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    A study of Bc+K+Kπ+B_c^+\to K^+K^-\pi^+ decays is performed for the first time using data corresponding to an integrated luminosity of 3.0 fb1\mathrm{fb}^{-1} collected by the LHCb experiment in pppp collisions at centre-of-mass energies of 77 and 88 TeV. Evidence for the decay Bc+χc0(K+K)π+B_c^+\to\chi_{c0}(\to K^+K^-)\pi^+ is reported with a significance of 4.0 standard deviations, resulting in the measurement of σ(Bc+)σ(B+)×B(Bc+χc0π+)\frac{\sigma(B_c^+)}{\sigma(B^+)}\times\mathcal{B}(B_c^+\to\chi_{c0}\pi^+) to be (9.83.0+3.4(stat)±0.8(syst))×106(9.8^{+3.4}_{-3.0}(\mathrm{stat})\pm 0.8(\mathrm{syst}))\times 10^{-6}. Here B\mathcal{B} denotes a branching fraction while σ(Bc+)\sigma(B_c^+) and σ(B+)\sigma(B^+) are the production cross-sections for Bc+B_c^+ and B+B^+ mesons. An indication of bˉc\bar b c weak annihilation is found for the region m(Kπ+)<1.834GeV ⁣/c2m(K^-\pi^+)<1.834\mathrm{\,Ge\kern -0.1em V\!/}c^2, with a significance of 2.4 standard deviations.Comment: All figures and tables, along with any supplementary material and additional information, are available at https://lhcbproject.web.cern.ch/lhcbproject/Publications/LHCbProjectPublic/LHCb-PAPER-2016-022.html, link to supplemental material inserted in the reference

    Measurement of the Bs0J/ψηB_{s}^{0} \rightarrow J/\psi \eta lifetime

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    Using a data set corresponding to an integrated luminosity of 3fb13 fb^{-1}, collected by the LHCb experiment in pppp collisions at centre-of-mass energies of 7 and 8 TeV, the effective lifetime in the Bs0J/ψηB^0_s \rightarrow J/\psi \eta decay mode, τeff\tau_{\textrm{eff}}, is measured to be τeff=1.479±0.034 (stat)±0.011 (syst)\tau_{\textrm{eff}} = 1.479 \pm 0.034~\textrm{(stat)} \pm 0.011 ~\textrm{(syst)} ps. Assuming CPCP conservation, τeff\tau_{\textrm{eff}} corresponds to the lifetime of the light Bs0B_s^0 mass eigenstate. This is the first measurement of the effective lifetime in this decay mode.Comment: All figures and tables, along with any supplementary material and additional information, are available at https://lhcbproject.web.cern.ch/lhcbproject/Publications/LHCbProjectPublic/LHCb-PAPER-2016-017.htm
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