220 research outputs found
Cytotoxicity and antibacterial studies of iridoids and phenolic compounds isolated from the latex of Himatanthus sucuuba
The latex of Himatanthus sucuuba (Spruce) Woodson, used popularly in the Amazon for the treatment of tumors, gastritis, inflammations and infections, was evaluated for cytotoxicity and antibacterial activities. The iridoid lactones, plumericin and isoplumericin were isolated from latex by bioassay fractionation and were found to be associated with DNA damage. Gallic acid exhibited the highest antimicrobial activity among the phenolic compounds isolated from the aqueous fraction. The compounds associated to cytotoxicity and antimicrobial activities could be responsible to the effects of this species used in traditional medicine.Key words: Himatanthus sucuuba, iridoids, phenolics, cytotoxicity, antibacterial
Protein synthesis and degradation gene SNPs related to feed intake, feed efficiency, growth, and ultrasound carcass traits in Nellore cattle.
We looked for possible associations of SNPs in genes related to protein turnover, with growth, feed efficiency and carcass traits in feedlot Nellore cattle. Purebred Nellore bulls and steers (N = 290; 378 ± 42 kg body weight, 23 months ± 42 days old) were evaluated for daily feed intake, body weight gain (BWG), gross feed efficiency, feed conversion ratio, partial efficiency of growth, residual feed intake (RFI), ultrasound backfat, rump fat, and ribeye area
Cross-Cultural Adaptation and Validation of SNOT-20 in Portuguese
Introduction. Chronic rhinosinusitis is a highly prevalent disease, so it is necessary to create valid instruments to assess the quality of life of these patients. The SNOT-20 questionnaire was developed for this purpose as a specific test to evaluate the quality of life related to chronic rhinosinusitis. It was validated in the English language, and it has been used in most studies on this subject. Currently, there is no validated instrument for assessing this disease in Portuguese. Objective. Cross-cultural adaptation and validation of SNOT-20 in Portuguese. Patients and Methods. The SNOT-20 questionnaire underwent a meticulous process of cross-cultural adaptation and was evaluated by assessing its sensitivity, reliability, and validity. Results. The process resulted in an intelligible version of the questionnaire, the SNOT-20p. Internal consistency (Cronbach's alpha = 0.91, P < .001), reliability testing-retesting (r = 0.994, P < .001), content validity, validity of discrimination of patients without chronic rhinosinusitis (U = 44, P < .0001) and assessment of sensitivity to change (SRM = 1.53 and 1.09) were evaluated. Conclusion. We conducted a successful process of cross-cultural adaptation and validation of the SNOT-20 questionnaire into Portuguese
Evaluating the potential of biodiesel production through microalgae farming in photobioreactor and high rate ponds from wastewater treatment
In the last decade, the research works on microbial as a potential source of lipid for biodiesel production have been growing. In this work, the potential of a sludge from high-rate lagoons in urban sewage treatment, composed mainly by Chlorella sp., as oil source for biodiesel production, was studied. The potential of Chlorella sp. growth in photobioreactor under controlled conditions was also investigated. Low lipid content (up to 3%) was observed in both cases. The composition of both oils showed high amount of fatty acids and fatty acid based compounds, however there are also other non-fatty acid based lipids. Density and viscosity of biodiesel from biosolid oil were determined and the results showed that these physico-chemical properties do not match the specification required for biodiesel. The results showed that sewage sludge from Samambaia treatment station (DF, Brazil) and Chlorella sp. cultivated under the conditions described in this work are not potential sources of fatty material for biodiesel production
Operations of and Future Plans for the Pierre Auger Observatory
Technical reports on operations and features of the Pierre Auger Observatory,
including ongoing and planned enhancements and the status of the future
northern hemisphere portion of the Observatory. Contributions to the 31st
International Cosmic Ray Conference, Lodz, Poland, July 2009.Comment: Contributions to the 31st ICRC, Lodz, Poland, July 200
Measurement of the Depth of Maximum of Extensive Air Showers above 10^18 eV
We describe the measurement of the depth of maximum, Xmax, of the
longitudinal development of air showers induced by cosmic rays. Almost four
thousand events above 10^18 eV observed by the fluorescence detector of the
Pierre Auger Observatory in coincidence with at least one surface detector
station are selected for the analysis. The average shower maximum was found to
evolve with energy at a rate of (106 +35/-21) g/cm^2/decade below 10^(18.24 +/-
0.05) eV and (24 +/- 3) g/cm^2/decade above this energy. The measured
shower-to-shower fluctuations decrease from about 55 to 26 g/cm^2. The
interpretation of these results in terms of the cosmic ray mass composition is
briefly discussed.Comment: Accepted for publication by PR
Suscetibilidade de cultivares de arroz irrigado (Oryza sativa) à deriva simulada do herbicida imazethapyr + imazapic
The Fluorescence Detector of the Pierre Auger Observatory
The Pierre Auger Observatory is a hybrid detector for ultra-high energy
cosmic rays. It combines a surface array to measure secondary particles at
ground level together with a fluorescence detector to measure the development
of air showers in the atmosphere above the array. The fluorescence detector
comprises 24 large telescopes specialized for measuring the nitrogen
fluorescence caused by charged particles of cosmic ray air showers. In this
paper we describe the components of the fluorescence detector including its
optical system, the design of the camera, the electronics, and the systems for
relative and absolute calibration. We also discuss the operation and the
monitoring of the detector. Finally, we evaluate the detector performance and
precision of shower reconstructions.Comment: 53 pages. Submitted to Nuclear Instruments and Methods in Physics
Research Section
Atmospheric effects on extensive air showers observed with the Surface Detector of the Pierre Auger Observatory
Atmospheric parameters, such as pressure (P), temperature (T) and density,
affect the development of extensive air showers initiated by energetic cosmic
rays. We have studied the impact of atmospheric variations on extensive air
showers by means of the surface detector of the Pierre Auger Observatory. The
rate of events shows a ~10% seasonal modulation and ~2% diurnal one. We find
that the observed behaviour is explained by a model including the effects
associated with the variations of pressure and density. The former affects the
longitudinal development of air showers while the latter influences the Moliere
radius and hence the lateral distribution of the shower particles. The model is
validated with full simulations of extensive air showers using atmospheric
profiles measured at the site of the Pierre Auger Observatory.Comment: 24 pages, 9 figures, accepted for publication in Astroparticle
Physic
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