90 resultados para Pre loads


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A simple HPLC/UV method was developed for the determination of the anticancer candidate LaSOM 65 in rat plasma. Samples were cleaned by protein precipitation with acetonitrile (recovery > 95%), after which they were subjected to chromatography under the isocratic elution of an acetonitrile:water (45:55, ν/ν) solution with detection at 303 nm. The method was linear (r² > 0.98) over the concentration range (0.05-2 µg mL-1) with intra- and inter-day precision ranging from 9.6% to 13.6% and 4.3% to 5.4%, respectively. The accuracy of the method ranged from 85% to 113.6%, and it showed sufficient sensitivity to determine pharmacokinetic parameters of LaSOM 65 after intravenous administration to Wistar rats.

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Silica gel chemically modified with 2-Aminotiazole groups, abbreviated as SiAT, was used for preconcentration of copper, zinc, nickel and iron from kerosene, normally used as a engine fuel for airplanes. Surface characteristics and surface area of the silica gel were obtained before and after chemical modification using FT-IR, Kjeldhal and surface area analysis (B.E.T.). The retention and recovery of the analyte elements were studied by applying batch and column techniques. The experimental parameters, such as shaking time in batch technique, flow rate and concentration of the eluent (HCl- 0.25-2.00 mol L-1) and the amount of silica, on retention and elution, have been investigated. Detection limits of the method for copper, iron, nickel and zinc are 0.77, 2.92, 1.73 and 0.097 mg L-1, respectively. The sorption-desorption of the studied metal ions made possible the development of a preconcentration method for metal ions at trace level in kerosene using flame AAS for their quantification.

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The benefit promoted by ectomycorrhizal depends on the interaction between symbionts and phosphorus (P) contents. Phosphorus effect on ectomycorrhizal formation and the effectiveness of these in promoting plant growth for fungal pre-selection were assessed under in vitro conditions. For P effect evaluation, Eucalyptus urophylla seedlings inoculated with four Pisolithus sp. isolates and others non-inoculated were grown on substrate containing 0.87, 1.16 and 1.72 mg P per plant. For evaluation of effectiveness and fungal pre-selection, other 30 isolates of Pisolithus sp., Pisolithus microcarpus ITA06 isolate, Amanita muscaria AM16 isolate, Scleroderma areolatum SC129 isolate were studied. D26 isolate promoted the highest plant heights for the three P doses, D51 at the lower dose and D72 at the intermediate dose. P doses did not influenced shoot fresh weight and fungal colonization. In the pre-selection of fungi, 14 isolates of Pisolithus sp., P. microcarpus ITA06 isolate and S. areolatum SC129isolate increased plant height and fresh weight. D82 isolate of Pisolithus sp. had effect singly on plant height while D17 and D58 on fresh weight. Of these, only D15, D17, D58 and ITA06 had typical ectomycorrhizae. The cultivation in vitro has shown adequate for pre-selection of ectomycorrhizal fungi. Colonization and benefits depend on species and isolate. D15, D17 and D58 of Pisolithus sp. and P. microcarpus isolate ITA06 are the most promising for nursery studies.

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The aim of this paper was to evaluate the automated acclimatization effects during pre-milking of cows on thermal conditioning, physiology, milk production and cost-benefit of the automated adiabatic evaporative cooling system (AECS). The treatments 20; 30; 40 min and control consisted of exposure time of pre-milking cows to the automated AECS. Sixteen cows were used with an average daily milk yield of 19 kg, distributed in a 4 x 4 Latin square design. The Tukey's test (P<0.05) was used to compare the means. The environmental variables, dry bulb temperature (DBT, ºC) and relative humidity (RH, %), were recorded every minute, which allowed the determination of the system efficiency through the Temperature and Humidity Index (THI). The respiratory rate (RR), rectal temperature (RT) and temperature of the coat (TC) were measured before and after the acclimatization. The 40 min treatment kept the environmental variables and the comfort indexes within recommended limits. The physiological variables (RR, RT and TC) were lower in the 40 min treatment and reflected positively on milk production, which increased 3.66% compared to the control treatment. The system was profitable, having a 43 days return on investment and a monthly revenue increase of R$ 1,992.67.

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The seeding process was the operation that suffered the most changes in no-tillage system due the cover crop soil and new particle soil arrangement. The objective of this study was to verify the effects of loads applied to the wheels and adjustments of sowing depth on seedling emergence of corn in no-tillage system. The experimental design was completely randomized with a factorial arrangement 5x4, with five loads applied to the wheels and four theoretical sowing depth adjustments. The real sowing depth increased in the lower theoretical depth and decreased in the higher theoretical depth, due to the compaction loads. Regarding the time of emergence, loads applied had not influence at the greater depths. Emergence time decreased with the load increase in the lower depths. Thus, the adjustment of the compactor wheels can influence in the corn seeding process.

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The theme of the research is the development of the domain of marketing knowledge in the design of agricultural machinery. It is developed throughout the design of agricultural machinery in order to identify the corporate and customers needs and to develop strategies to satisfy these needs. The central problem of the research questions which marketing tools to apply on pre-development process of farm machinery, in order to increase the market value of the products and of the company and, consequently, generate competitive advantage to the manufacturers of agricultural machinery. As methodology, it was developed bibliographical research and multicase study of the development process of agricultural machinery developed by small, medium and large companies and the academy. As a result, a marketing reference model was elaborated for the pre-development stage of agricultural machinery, which outlines the activities, tasks, mechanisms and controls that can be used in strategic planning and in products planning of agricultural machinery manufacturers, contributing to explain the explicit knowledge in the marketing field.

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Due to the importance of the environment on animal production and thus environmental control, the study aims to build a system for monitoring and control the meteorological variables, temperature and relative humidity, low cost, which can be associated with an evaporative cooling system (ECS). The system development included all the stages of assembly, test and laboratory calibration, and later the validation of the equipment carried in the field. The validation step showed results which allowed concluding that the system can be safely used in the monitoring of these variables. The controller was efficient in management of the microclimate in the waiting corral and allowed the maintenance of the air temperature within the comfort range for dairy cattle in pre-milking with averaged 25.09 ºC during the afternoon. The equipment showed the lower cost (R$ 325.76) when compared to other middle market (R$ 450.00).

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The interaction between the soil and tillage tool can be examined using different parameters for the soil and the tool. Among the soil parameters are the shear stress, cohesion, internal friction angle of the soil and the pre-compression stress. The tool parameters are mainly the tool geometry and depth of operation. Regarding to the soils of Rio Grande do Sul there are hardly any studies and evaluations of the parameters that have importance in the use of mathematical models to predict tensile loads. The objective was to obtain parameters related to the soils of Rio Grande do Sul, which are used in soil-tool analysis, more specifically on mathematical models that allow the calculation of tractive effort for symmetric and narrow tools. Two of the main soils of Rio Grande do Sul, an Albaqualf and a Paleudult were studied. Equations that relate the cohesion, internal friction angle of the soil, adhesion, soil-tool friction angle and pre-compression stress as a function of water content in the soil were obtained, leading to important information for use of mathematical models for tractive effort calculation.

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The objective of this study was to characterize the microclimatic profile of broiler transport trucks under commercial conditions, in the summer, by continuous monitoring of environmental variables (temperature and air relative humidity). Three loads were monitored from farm to slaughterhouse, considering factors such as distance and day periods (morning, afternoon, and night). To obtain the profile of the environmental variables during journey, data loggers, that determined the microclimate to which birds were submitted, were installed in the trucks; data loggers also allowed visualization of the Enthalpy Comfort Index (ECI) so that load regions could be classified according to heat comfort limits for 6-week old poultries. Temperature, relative humidity, and ECI in the truck were analyzed, using geostatistics, by the ordinary kriging method. The afternoon was the most critical period, and truck central and rear regions were most problematic for chickens, thus most susceptible to losses.

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The aim of this study was to investigate the effect of pre-slaughter handling on the occurrence of PSE (Pale, Soft, and Exudative) meat in swine slaughtered at a commercial slaughterhouse located in the metropolitan region of Dourados, Mato Grosso do Sul, Brazil. Based on the database (n=1,832 carcasses), it was possible to apply the integrated multivariate analysis for the purpose of identifying, among the selected variables, those of greatest relevance to this study. Results of the Principal Component Analysis showed that the first five components explained 89.28% of total variance. In the Factor Analysis, the first factor represented the thermal stress and fatiguing conditions for swine during pre-slaughter handling. In general, this study indicated the importance of the pre-slaughter handling stages, evidencing those of greatest stress and threat to animal welfare and pork quality, which are transport time, resting period, lairage time before unloading, unloading time, and ambience.

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Energy consumption in the world has been growing every year. The industrial sector represents 27.32% of the world energy demand. Heating systems that use solar energy may contribute with a percentage of the total energy required by industries. This work aimed to study the use of vacuum solar collectors for water pre-heating in boilers. We used four collectors installed according to NBR 15,569; water flow through the tubes was 0.058 L/s, and temperature in the inlet and outlet pipes was measured. Results showed that instantaneous radiation, and inlet fluid and room temperatures are variables that influence the process, reaching water maximum temperature in the solar collector outlet of 97.9 °C, and efficiency of approximately 65% for most experiments. For the financial viability evaluation, the payback study was applied, which resulted in 4; 7 and 5 years, for the respective sources: firewood, LPG (liquefied petroleum gas), and electricity. Regarding the calculation of the annual contribution to the reduction of greenhouse gases, it was, respectively, 2.162 and 356 kg of CO2 per m² of collector tubes, in comparison with firewood and LPG.

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Brazil is amongst the world’s largest swine producers. However, its competitiveness has been vulnerable due to a lack of cooperation between the supply chain players. This condition makes the financial losses to be evaluated taking into account only an individual node, and most of the time, these damages are imputed by swine breeders. Living weight losses occur between the farm to slaughterhouses, and the main cause of these losses is the pre-slaughter handling, especially during animal transportation. In this research, we analyzed the pre-slaughter handling in a swine farm in Brasilândia, MS, Brazil. Analyzed data were provided by five slaughterhouses (farm clients) from the studied region, in which it was considered living weight losses, carcass bruising, animal injury, and death rate. The results indicated that total financial losses represent 160 thousand dollars per year, when taking into account the supply chain management.

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ABSTRACT The successful in the implementation of wind turbines depends on several factors, including: the wind resource at the installation site, the equipment used, project acquisition and operational costs. In this paper, the production of electricity from two small wind turbines was compared through simulation using the computer software HOMER - a national model of 6kW and an imported one of 5kW. The wind resources in three different cities were considered: Campinas (SP/BR), Cubatão (São Paulo/BR) and Roscoe (Texas/ USA). A wind power system connected to the grid and a wind isolated system - batteries were evaluated. The results showed that the energy cost ($/kWh) is strongly dependent on the windmill characteristics and local wind resource. Regarding the isolated wind system – batteries, the full supply guarantee to the simulated electrical load is only achieved with a battery bank with many units and high number of wind turbines, due to the intermittency of wind power.

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The hormone oxytocin is released by the neuropituitary gland through stimulation of the neurons of the supraoptic and paraventricular nuclei of the hypothalamus. In order to determine the physiological concentrations of this hormone in domestic cats, blood samples were collected from 15 male animals (Felis silvestris catus) during the pre- and post-puberty periods (at four and eight months of age, respectively). Oxytocin determination was accomplished by radioimmunoassay. The average oxytocin concentrations measured in the pre- and post-puberty periods were 2.54±0.24 (μg/dL) and 2.53±0.28 (μg/dL), respectively, and there were no statistical differences between these measurements. Because there are few literature on the analysis of this hormone, especially in the case of male Felis silvestris catus, more studies on the influence of oxytocin on the physiology and reproduction of this species should be conducted under maintenance and situations of stress (such as transportation), and other routine events.