50 research outputs found

    EXTRATO DE MAMONA COMO MANIPULADOR DA FERMENTAÇÃO RUMINAL

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    Objetivou-se investigar os efeitos da adição do extrato de farelo de mamona (EFM) sobre o perfil da fermentação ruminal in vitro em dietas com alto e baixo teor de forragem. Utilizou-se ensaio de incubação ruminal in vitro com dois controles, um negativo (sem aditivo) e um positivo (monensina sódica) e EFM liofilizado (20, 40 e 60 mg/frasco). Em condições de alto teor de forragem na dieta, a adição do EFM aumentou o pH do meio e a concentração de acetato, reduziu a produção de gás, mas não afetou a produção de gás por unidade de matéria seca (MS) digerida em relação ao tratamento controle. Em comparação com monensina sódica, o EFM reduziu as concentrações de propionato e amônia e aumentou a produção de gás por unidade de MS digerida. Em condições de baixo teor de forragem, a adição do EFM reduziu o pH e potencial redox do meio em relação ao tratamento controle. Em comparação com a monensina sódica, o EFM reduziu o pH do meio e a produção total de gás, mas não afetou a produção de gás por unidade de MS digerida. O extrato de farelo de mamona destoxificado não apresenta potencial como manipulador da fermentação ruminal.Palavras-chave: amônia; digestibilidade; eficiência; metano. CASTOR BEAN EXTRACT AS A MANIPULATOR OF RUMINAL FERMENTATION ABSTRACT: Effects of the castorbean meal extract (CME) on ruminal in vitro were investigate in high and low forage diet conditions. For each dietary condition, one in vitro ruminal incubation experiment was conducted in a completely randomized design, with nine repetitions per treatment (three animal inoculum donators and three 48 hors-incubations). In high forage diet, CME increased ruminal pH acetate concentration, reduced gas production, but it did not affect the gas production per unit of digested dry matter (DM), in relation to control treatment. Compare to monensin sodium, CME reduced propionate and ammonia concentrations and increased gas production per unit of digested DM, indicating that CME reduces ruminal energetic efficiency. In low forage diet, CME reduced pH and redox potential compare to control. Compare to monensin sodium, CME reduced pH and gas production, but it did not affect gas production per unit of digested DM. Castorbean meal extract does not present potential as manipulator of the ruminal fermentation.Keywords: ammonia; digestibility; efficiency; methane

    Proteomics-based identification of differentially abundant proteins reveals adaptation mechanisms of Xanthomonas citri subsp citri during Citrus sinensis infection

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    Background: Xanthomonas citri subsp. citri (Xac) is the causal agent of citrus canker. A proteomic analysis under in planta infectious and non-infectious conditions was conducted in order to increase our knowledge about the adaptive process of Xac during infection. Results: For that, a 2D-based proteomic analysis of Xac at 1, 3 and 5 days after inoculation, in comparison to Xac growth in NB media was carried out and followed by MALDI-TOF-TOF identification of 124 unique differentially abundant proteins. Among them, 79 correspond to up-regulated proteins in at least one of the three stages of infection. Our results indicate an important role of proteins related to biofilm synthesis, lipopolysaccharides biosynthesis, and iron uptake and metabolism as possible modulators of plant innate immunity, and revealed an intricate network of proteins involved in reactive oxygen species adaptation during Plants'Oxidative Burst response. We also identified proteins previously unknown to be involved in Xac-Citrus interaction, including the hypothetical protein XAC3981. A mutant strain for this gene has proved to be non-pathogenic in respect to classical symptoms of citrus canker induced in compatible plants. Conclusions: This is the first time that a protein repertoire is shown to be active and working in an integrated manner during the infection process in a compatible host, pointing to an elaborate mechanism for adaptation of Xac once inside the plant.Fundacao de Amparo a Pesquisa do Estado de Sao PauloFundacao de Amparo a Pesquisa do Estado de Minas GeraisBIGA grant-CAPESUniv Fed Ouro Preto, Inst Ciencias Exatas & Biol, Dept Ciencias Biol DECBI, Ouro Preto, MG, BrazilUniv Fed Ouro Preto, Nucleo Pesquisas Ciencias Biol NUPEB, Ouro Preto, MG, BrazilUniv Fed Rio de Janeiro, Inst Quim, Dept Bioquim DBq, Rio De Janeiro, RJ, BrazilUniv Estadual Paulista, UNESP, Dept Tecnol, Fac Ciencias Agr & Vet Jaboticabal, Jaboticabal, SP, BrazilUniv Estadual Campinas, UNICAMP, Inst Quim, Campinas, SP, BrazilUniv Sao Paulo, Inst Quim, Dept Bioquim, Sao Paulo, SP, BrazilUniv Fed Sao Paulo UNIFESP, Dept Ciencias Biol, Diadema, SP, BrazilVirginia Tech, Biocomplex Inst, Blacksburg, VA USAUniv Sao Paulo, Inst Quim, Dept Bioquim, Sao Paulo, SP, BrazilUniv Fed Sao Paulo UNIFESP, Dept Ciencias Biol, Diadema, SP, BrazilCAPESFAPESP: 04/02006-7Fundacao de Amparo a Pesquisa do Estado de Minas Gerais: CBB-APQ-04425-10BIGA grant-CAPES: 3385/2013Web of Scienc

    Measurement of the cosmic ray spectrum above 4×10184{\times}10^{18} eV using inclined events detected with the Pierre Auger Observatory

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    A measurement of the cosmic-ray spectrum for energies exceeding 4×10184{\times}10^{18} eV is presented, which is based on the analysis of showers with zenith angles greater than 6060^{\circ} detected with the Pierre Auger Observatory between 1 January 2004 and 31 December 2013. The measured spectrum confirms a flux suppression at the highest energies. Above 5.3×10185.3{\times}10^{18} eV, the "ankle", the flux can be described by a power law EγE^{-\gamma} with index γ=2.70±0.02(stat)±0.1(sys)\gamma=2.70 \pm 0.02 \,\text{(stat)} \pm 0.1\,\text{(sys)} followed by a smooth suppression region. For the energy (EsE_\text{s}) at which the spectral flux has fallen to one-half of its extrapolated value in the absence of suppression, we find Es=(5.12±0.25(stat)1.2+1.0(sys))×1019E_\text{s}=(5.12\pm0.25\,\text{(stat)}^{+1.0}_{-1.2}\,\text{(sys)}){\times}10^{19} eV.Comment: Replaced with published version. Added journal reference and DO

    Energy Estimation of Cosmic Rays with the Engineering Radio Array of the Pierre Auger Observatory

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    The Auger Engineering Radio Array (AERA) is part of the Pierre Auger Observatory and is used to detect the radio emission of cosmic-ray air showers. These observations are compared to the data of the surface detector stations of the Observatory, which provide well-calibrated information on the cosmic-ray energies and arrival directions. The response of the radio stations in the 30 to 80 MHz regime has been thoroughly calibrated to enable the reconstruction of the incoming electric field. For the latter, the energy deposit per area is determined from the radio pulses at each observer position and is interpolated using a two-dimensional function that takes into account signal asymmetries due to interference between the geomagnetic and charge-excess emission components. The spatial integral over the signal distribution gives a direct measurement of the energy transferred from the primary cosmic ray into radio emission in the AERA frequency range. We measure 15.8 MeV of radiation energy for a 1 EeV air shower arriving perpendicularly to the geomagnetic field. This radiation energy -- corrected for geometrical effects -- is used as a cosmic-ray energy estimator. Performing an absolute energy calibration against the surface-detector information, we observe that this radio-energy estimator scales quadratically with the cosmic-ray energy as expected for coherent emission. We find an energy resolution of the radio reconstruction of 22% for the data set and 17% for a high-quality subset containing only events with at least five radio stations with signal.Comment: Replaced with published version. Added journal reference and DO

    Measurement of the Radiation Energy in the Radio Signal of Extensive Air Showers as a Universal Estimator of Cosmic-Ray Energy

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    We measure the energy emitted by extensive air showers in the form of radio emission in the frequency range from 30 to 80 MHz. Exploiting the accurate energy scale of the Pierre Auger Observatory, we obtain a radiation energy of 15.8 \pm 0.7 (stat) \pm 6.7 (sys) MeV for cosmic rays with an energy of 1 EeV arriving perpendicularly to a geomagnetic field of 0.24 G, scaling quadratically with the cosmic-ray energy. A comparison with predictions from state-of-the-art first-principle calculations shows agreement with our measurement. The radiation energy provides direct access to the calorimetric energy in the electromagnetic cascade of extensive air showers. Comparison with our result thus allows the direct calibration of any cosmic-ray radio detector against the well-established energy scale of the Pierre Auger Observatory.Comment: Replaced with published version. Added journal reference and DOI. Supplemental material in the ancillary file

    Global maps of soil temperature

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    Research in global change ecology relies heavily on global climatic grids derived from estimates of air temperature in open areas at around 2 m above the ground. These climatic grids do not reflect conditions below vegetation canopies and near the ground surface, where critical ecosystem functions occur and most terrestrial species reside. Here, we provide global maps of soil temperature and bioclimatic variables at a 1-km² resolution for 0–5 and 5–15 cm soil depth. These maps were created by calculating the difference (i.e., offset) between in-situ soil temperature measurements, based on time series from over 1200 1-km² pixels (summarized from 8500 unique temperature sensors) across all the world’s major terrestrial biomes, and coarse-grained air temperature estimates from ERA5-Land (an atmospheric reanalysis by the European Centre for Medium-Range Weather Forecasts). We show that mean annual soil temperature differs markedly from the corresponding gridded air temperature, by up to 10°C (mean = 3.0 ± 2.1°C), with substantial variation across biomes and seasons. Over the year, soils in cold and/or dry biomes are substantially warmer (+3.6 ± 2.3°C) than gridded air temperature, whereas soils in warm and humid environments are on average slightly cooler (-0.7 ± 2.3°C). The observed substantial and biome-specific offsets emphasize that the projected impacts of climate and climate change on near-surface biodiversity and ecosystem functioning are inaccurately assessed when air rather than soil temperature is used, especially in cold environments. The global soil-related bioclimatic variables provided here are an important step forward for any application in ecology and related disciplines. Nevertheless, we highlight the need to fill remaining geographic gaps by collecting more in-situ measurements of microclimate conditions to further enhance the spatiotemporal resolution of global soil temperature products for ecological applications

    Global maps of soil temperature.

    Get PDF
    Research in global change ecology relies heavily on global climatic grids derived from estimates of air temperature in open areas at around 2 m above the ground. These climatic grids do not reflect conditions below vegetation canopies and near the ground surface, where critical ecosystem functions occur and most terrestrial species reside. Here, we provide global maps of soil temperature and bioclimatic variables at a 1-km2 resolution for 0-5 and 5-15 cm soil depth. These maps were created by calculating the difference (i.e. offset) between in situ soil temperature measurements, based on time series from over 1200 1-km2 pixels (summarized from 8519 unique temperature sensors) across all the world's major terrestrial biomes, and coarse-grained air temperature estimates from ERA5-Land (an atmospheric reanalysis by the European Centre for Medium-Range Weather Forecasts). We show that mean annual soil temperature differs markedly from the corresponding gridded air temperature, by up to 10°C (mean = 3.0 ± 2.1°C), with substantial variation across biomes and seasons. Over the year, soils in cold and/or dry biomes are substantially warmer (+3.6 ± 2.3°C) than gridded air temperature, whereas soils in warm and humid environments are on average slightly cooler (-0.7 ± 2.3°C). The observed substantial and biome-specific offsets emphasize that the projected impacts of climate and climate change on near-surface biodiversity and ecosystem functioning are inaccurately assessed when air rather than soil temperature is used, especially in cold environments. The global soil-related bioclimatic variables provided here are an important step forward for any application in ecology and related disciplines. Nevertheless, we highlight the need to fill remaining geographic gaps by collecting more in situ measurements of microclimate conditions to further enhance the spatiotemporal resolution of global soil temperature products for ecological applications

    Leishmania enriettii: biochemical characterisation of lipophosphoglycans (LPGs) and glycoinositolphospholipids (GIPLs) and infectivity to Cavia porcellus

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    Background: Leishmania enriettii is a species non-infectious to man, whose reservoir is the guinea pig Cavia porcellus. Many aspects of the parasite-host interaction in this model are unknown, especially those involving parasite surface molecules. While lipophosphoglycans (LPGs) and glycoinositolphospholipids (GIPLs) of Leishmania species from the Old and New World have already been described, glycoconjugates of L. enriettii and their importance are still unknown.Methods: Mice peritoneal macrophages from C57BL/6 and knock-out (TLR2 -/-, TLR4 -/-) were primed with IFN-gamma and stimulated with purified LPG and GIPLs from both species. Nitric oxide and cytokine production were performed. MAPKs (p38 and JNK) and NF-kB activation were evaluated in J774.1 macrophages and CHO cells, respectively.Results: LPGs were extracted, purified and analysed by western-blot, showing that LPG from L88 strain was longer than that of Cobaia strain. LPGs and GIPLs were depolymerised and their sugar content was determined. LPGs from both strains did not present side chains, having the common disaccharide Gal(beta 1,4) Man(alpha 1)-PO4. the GIPL from L88 strain presented galactose in its structure, suggestive of type II GIPL. On the other hand, the GIPL of Cobaia strain presented an abundance of glucose, a characteristic not previously observed. Mice peritoneal macrophages from C57BL/6 and knock-outs (TLR2 -/- and TLR4 -/-) were primed with IFN-gamma and stimulated with glycoconjugates and live parasites. No activation of NO or cytokines was observed with live parasites. On the other hand, LPGs and GIPLs were able to activate the production of NO, IL-6, IL-12 and TNF-alpha preferably via TRL2. However, in CHO cells, only GIPLs were able to activate TRL2 and TRL4. in vivo studies using male guinea pigs (Cavia porcellus) showed that only strain L88 was able to develop more severe ulcerated lesions especially in the presence of salivary gland extract (SGE).Conclusion: the two L. enriettii strains exhibited polymorphisms in their LPGs and GIPLs and those features may be related to a more pro-inflammatory profile in the L88 strain
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