958 resultados para least limiting water range
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
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The effect of ultrasound and osmotic dehydration pretreatments on papaya drying kinetics was investigated. The ultrasound pretreatment was carried out in an ultrasonic bath at 30 A degrees C. The osmotic pretreatment in sucrose solution was carried out in an incubator at 34 A degrees C and agitation of 80 rpm for 210 min. The drying process was conducted in a fixed bed dryer at 70 A degrees C. Experimental data were fitted successfully using the Page model for dried fresh and pretreated fruits, with coefficient of determination greater than 0.9992 and average relative error lower that 14.4 %. The diffusional model was used to describe the moisture transfer, and the effective water diffusivity was identified in the order of 10(-9) m(2) s(-1). It was found that drying rates of osmosed fruits were the lowest due to the presence of infused solutes, while the ultrasound pretreatment contributed to faster drying rates. Evaluation of the dried fruit was performed by means of total carotenoids retention. Ultrasound treatments in distilled water prior to air-drying gave rise to dried papayas with retention of carotenoids in the range 30.4-39.8 % and the ultrasonic-assisted osmotic dehydration of papayas showed carotenoids retention values up to 64.9 %, whereas the dried fruit without pretreatment showed carotenoids retention lower than 24 %.
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This study aimed to investigate the genetic variability of two Brazilian free range (Caipira) chickens lines using microsatellites analysis of ten loci. It was collected a total of 99 blood samples, which 49 were from Paraiso Pedres (PP) and 50 were from Rubro Negra (RN) lines. The amplification of the DNA fragments was performed by polymerase chain reaction (PCR) and the genotyping was conduct using ABI 3130 sequencer. The allele number variation was among 3 (LEI0254) to 32 (LEI0212) in the PP line, and 4 (LEI0254) to 31 (LEI0212) in the RN line. The allelic average per locus was 13.3 and 13.1 in the PP and RN lines, respectively. The average observed and the expected heterozygosity were 0.650 and 0.820 in the PP line, and 0.671 and 0.804 in the RN line. All of the analyzed loci were informative (PIC>0.5). These results indicate that these free-range animals have a high genetic variability, at least for the majority of the analyzed loci, and this genetic variation is higher than the commercial chickens and similar for the no-commercial birds.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
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Phytochromes are red/far-red light photoreceptors that mediate a variety of photomorphogenic processes in plants, from germination to flowering. In addition, there is evidence that phytochromes are also part of the stress signalling response, especially in response to water deficit stress, which is the major abiotic factor limiting plant growth and crop productivity worldwide. In this study, we used the phyA (far red-insensitive; fri), phyB1 (temporary red-insensitive; tri) and phyB2 mutants of tomato (Solanum lycopersicum L.) to study the roles of these three phytochromes in drought stress responses. Compared to wild type (WT) plants grown under water-deficit stress conditions, the fri, tri, and phyB2 mutants did not exhibit altered dry weights, leaf areas, stomatal densities, or stomatal opening. The stomatal conductance of all three mutants was severely reduced under both fully-hydrated and water-deficit conditions. Although relative water contents did change after drought stress in each mutant, the most significant reduction in water potential during water stress was observed in the fri mutant. However, this mutant returned its water status to WT levels during rehydration. Although the phyB2 mutant lost more water from detached leaves during abscisic acid (ABA) treatment, phyB2 behaved like WT plants, indicating that this mutant was not insensitive to ABA. Overall, these results indicate that the phytochromes phyA, phyB1, and phyB2 modulate drought stress responses in tomato.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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In water distribution systems, old metallic pipes have been replaced by plastic pipes due to their deterioration over time. Although acoustic methods are effective in finding leaks in metallic pipes, they have been found to be problematic when applied to plastic pipes due to the high damping within the pipe wall and the surrounding medium. This is responsible for the leak signal not traveling long distances. Moreover, the leak energy in plastic pipes is generally located at a narrow frequency range located at low frequencies. However, the presence of resonances can narrow even more this frequency range. In order to minimise the influence of background noise and resonances on the calculation of the time delay estimate, band-pass filters are often used to supress undesirable frequency components of the noise. The objective of this paper is to investigate the influence of resonances in the pipe system (pipe, valves, connections and hydrants), on the time delay estimate calculated using acoustic signals. Analytical models and actual leak data collected in a bespoke rig located in the United Kingdom are used to investigate this feature.
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The aim of this work was the development and characterization of a biocompatible microemulsion (ME) containing soybean oil (O), phosphatidylcholine/sodium oleate/Eumulgin®HRE40 as the surfactant mixture (S) and water or buffer solution as the aqueous phase (W), for oral delivery of the poorly water-soluble drugs sulfamerazine (SMR) and indomethacin (INM). A wide range of combinations to obtain clear oil-in-water (o/w) ME was observed from pseudo-ternary phase diagrams, which was greater after the incorporation of both drugs, suggesting that they acted as stabilizers. Drug partition studies indicated a lower affinity of the drugs for the oil domain when they were ionized and with increased temperature, explained by the fact that both drugs were introduced inside the oil domain, determined by nuclear magnetic resonance. High concentrations of SMR and INM were able to be incorporated (22.0 and 62.3 mg/mL, respectively). The ME obtained presented an average droplet size of 100 nm and a negative surface charge. A significant increase in the release of SMR was observed with the ME with the highest percentage of O, because of the solubilizing properties of the ME. Also, a small retention effect was observed for INM, which may be explained by the differences in the partitioning properties of the drugs. © 2015 Wiley Periodicals, Inc. and the American Pharmacists Association J Pharm Sci 104:3535-3543, 2015.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Ultraviolet (UV) filters are widely used in the formulation of personal care products (PCPs) to prevent damage to the skin, lips, and hair caused by excessive UV radiation. Therefore, large amounts of these substances are released daily into the aquatic environment through either recreational activities or the release of domestic sewage. The concern regarding the presence of such substances in the environment and the exposure of aquatic organisms is based on their potential for bioaccumulation and their potential as endocrine disruptors. Although there are several reports regarding the occurrence and fate of UV filters in the aquatic environment, these compounds are still overlooked in tropical areas. In this study, we investigated the occurrence of the organic UV filters benzophenone-3 (BP-3), ethylhexyl salicylate (ES), ethylhexyl methoxycinnamate (EHMC), and octocrylene (OC) in six water treatment plants in various cities in Southeast Brazil over a period of 6 months to 1 year. All of the UV filters studied were detected at some time during the sampling period; however, only EHMC and BP-3 were found in quantifiable concentrations, ranging from 55 to 101 and 18 to 115 ng L(-1), respectively. Seasonal variation of BP-3 was most clearly noticed in the water treatment plant in Araraquara, São Paulo, where sampling was performed for 12 months. BP-3 was not quantifiable in winter but was quantifiable in summer. The levels of BP-3 were in the same range in raw, treated and chlorinated water, indicating that the compound was not removed by the water treatment process.
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A method for the identification and quantification of pesticide residues in water, soil, and sediment samples has been developed, validated, and applied for the analysis of real samples. The specificity was determined by the retention time and the confirmation and quantification of analyte ions. Linearity was demonstrated over the concentration range of 20 to 120 µg L(-1), and the correlation coefficients varied between 0.979 and 0.996, depending on the analytes. The recovery rates for all analytes in the studied matrix were between 86% and 112%. The intermediate precision and repeatability were determined at three concentration levels (40, 80, and 120 µg L(-1)), with the relative standard deviation for the intermediate precision between 1% and 5.3% and the repeatability varying between 2% and 13.4% for individual analytes. The limits of detection and quantification for fipronil, fipronil sulfide, fipronil-sulfone, and fipronil-desulfinyl were 6.2, 3.0, 6.6, and 4.0 ng L(-1) and 20.4, 9.0, 21.6, and 13.0 ng L(-1), respectively. The method developed was used in water, soil, and sediment samples containing 2.1 mg L(-1) and 1.2% and 5.3% of carbon, respectively. The recovery of pesticides in the environmental matrices varied from 88.26 to 109.63% for the lowest fortification level (40 and 100 µg kg(-1)), from 91.17 to 110.18% for the intermediate level (80 and 200 µg kg(-1)), and from 89.09 to 109.82% for the highest fortification level (120 and 300 µg kg(-1)). The relative standard deviation for the recovery of pesticides was under 15%.
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This study aims to determine physical properties of particleboard made of sawmill waste, as a mix of several wood species, and two adhesives: urea-formaldehyde, usually employed in industry (even with drawbacks or formaldehyde emission during pressing) and FASTBOND®, water based resin, still poorly referenced in literature. Sixteen panels have been produced, in four experimental conditions, defined by using two adhesives and a 12 mm thick limiter (or not). Variance analysis was adopted to evaluate influence of experimental conditions on physical properties of produced panels, manufactured in nominal dimensions 350x350mm; 10% resin related to particles mass (at 5% moisture); 3.5 MPa compaction pressure, temperature 130°C, in a 10 min cycle. Tests to determine density, moisture content, swelling and water absorption were carried out based on normative parameters of ABNT NBR 14810:2006. Results have been satisfactory to panels produced with urea-formaldehyde but those manufactured with polychloroprene based resin (FASTBOND®) not meet regulatory requirements. Best results have been obtained without limiter.
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Freshwater copepods were sampled in the La Plata River basin to identify the processes that affect beta diversity and to determine the main factors influencing their geographical distribution and patterns of endemism. Beta diversity patterns exhibited strong dissimilarity between locations; the turnover process was predominant and indicated a replacement of species along the basin. Redundancy analysis indicated the presence of two large sets of species separated geographically by a boundary zone, with several associated variables. Northern species were associated with water transparency and temperature, mean air temperature, mean air temperature during winter and minimum air temperature of coldest month, indicating that these species are not tolerant to low temperatures and are abundant in reservoirs that are common in the upper stretch of the Paraná River basin. Southern species were related with amplitude of air temperature, turbidity, total phosphorus and total suspended matter, indicating that these species are polythermic and have adapted to live in river stretches. From 20 environmental variables analyzed in our study, partial least squares analysis indicated four variables with increased retention of effects on copepod abundance: air temperature, minimum temperature of coldest month, turbidity and transparency. Because almost all of the species found in this study occurred across a wide range of habitat types, the cause of the separation between river and reservoir species could be considered to be more anthropogenic than natural, and it primarily affected species abundance. For certain members of the northern group of copepod species, distribution was dependent on high temperatures, whereas the distribution of the southern group indicated that the species were polythermic.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)