946 resultados para Global effect index


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Glassy films of Ga10Ge25S65 with 4 mu m thickness were deposited on quartz substrates by electron beam evaporation. Photoexpansion (PE) (photoinduced increase in volume) and photobleaching (PB) (blue shift of the bandgap) effects have been examined. The exposed areas have been analyzed using perfilometer and an expansion of 1.7 mu m (Delta V/V approximate to 30%) is observed for composition Ga10Ge25S65 exposed during 180 min and 3 mW/cm(2) power density. The optical absorption edge measured for the film Ge25Ga10S65 above and below the bandgap show that the blue shift of the gap by below bandgap photon illumination is considerable higher (Delta E-g = 440 meV) than Delta E-g induced by above bandgap illumination (Delta E-g = 190 meV). The distribution of the refraction index profile showed a negative change of the refraction index in the irradiated samples (Delta n = -0.6). The morphology was examined using a scanning electron microscopy (SEM). The chemical compositions measured using an energy dispersive analyzer (EDX) indicate an increase of the oxygen atoms into the irradiated area. Using a Lloyd's mirror setup for continuous wave holography it was possible to record holographic gratings using the photoinduced effects that occur in them. Diffraction efficiency up to 25% was achieved for the recorded gratings and atomic force microscopy images are presented. (c) 2005 Elsevier B.V. All rights reserved.

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Objective. The purpose of this study was to evaluate the effect of total abdominal hysterectomy on ovarian blood supply using transvaginal color Doppler ultrasonography in women of reproductive age. Methods. This prospective study included 61 women aged 40 years or younger who were divided into 2 groups: group 1, comprising 31 patients who underwent total abdominal hysterectomy (TAH), and group 2, comprising 30 women with no abnormalities. Inclusion criteria included normal ovarian function at baseline, with basal follicle-stimulating hormone levels of less than 15 mUI/mL, normal body weight, no tobacco use, and no history of laparotomy or ovarian disease. Ovarian arterial blood supply by determination of the pulsatility index (PI) on Doppler analysis and ovarian volume on transvaginal ultrasonography were assessed at baseline and at 6 and 12 postoperative months. The Student t test, profile analysis, and Friedman and Mann-Whitney tests were used in the statistical analysis of data. Results. Statistical analysis of baseline data revealed that both groups were homogeneous. At months 6 and 12, greater ovarian volumes and lower PI values were observed in patients who underwent TAH (P < .05). By the end of the study, in 8 of the 31 patients who underwent TAH (25.5%), benign ovarian cysts were observed. in the control group, all the parameters studied remained unchanged. Conclusions. The reduced PI values observed on Doppler ultrasonography suggested a decrease in the resistance flow in the ovarian arteries in women of reproductive age who underwent TAH.

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Comm indica L. is an herbaceous species with ornamental and medicinal value, having seeds with a hard seed coat. This study aimed to test the influence of constant temperatures ranging from 5 to 45 C, at 5 C intervals, on the germination of scarified seeds. Data obtained were analyzed through the model of enthalpy of activation in order to obtain the optimum temperature range for germination. The species showed seed germinability in a wide temperature range (10-40 degrees C) being the optimal temperature range between 13.84 and 34.41 degrees C, determined by the enthalpy of activation.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Globalisation trends and biorterrorism issues have led to new concerns relating to public health, animal health, international trade and food security. There is an imperative to internationalise and strengthen global public health capacity by renewed emphasis on veterinary public health in veterinary education and increasing opportunities for elective experiential learning in public practice programmes for veterinary students. Recent experience with a US-Brazil Higher Education Consortia Program is used as an example of potential ways in which veterinary students can gain an appreciation for global veterinary issues.

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In this analysis, using available hourly and daily radiometric data performed at Botucatu, Brazil, several empirical models relating ultraviolet (UV), photosynthetically active (PAR) and near infrared (NIR) solar global components with solar global radiation (G) are established. These models are developed and discussed through clearness index K(T) (ratio of the global-to-extraterrestrial solar radiation). Results obtained reveal that the proposed empirical models predict hourly and daily values accurately. Finally. the overall analysis carried Out demonstrates that the sky conditions are more important in developing correlation models between the UV component and the global solar radiation. The linear regression models derived to estimate PAR and NIR components may be obtained without sky condition considerations within a maximum variation of 8%. In the case of UV, not taking into consideration the sky condition may cause a discrepancy of up to 18% for hourly values and 15% for daily values. (C) 2008 Elsevier Ltd. All rights reserved.

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A performance trial was conducted with broiler chicks to Study the effect of phytase (PHY) supplementation in diets formulated With reduced AME, Ca, and P. The nutrient digestibility was determined during the 14- to 21-d and 28- to 35-d periods. The treatments consisted of 3 diets (NC1, NC2. NC3) differing ill nutrient content and each diet with Or without supplemental PHY (NC1, 0 oi 500; NC2, 0 or 750; NC3, 0 or 1,000 U of PHY/kg feed) and I positive control diet (PC). Compared with the PC diet. negative control diets (NC) resulted in lower AME and apparent ileal amino acid digestibility for some amino acids. Phytase Supplementation of the NC diets increased AME. apparent ileal amino acid digestibility, and apparent ileal crude protein digestibility. Phytase addition also increased mineral absorption in 2 1 - and 35-d-old broilers fed NC diets. Reduced nutrient digestibility appears to be I factor in the weight gain and feed intake results. Reducing Ca and P content reduced feed intake in a stepwise fashion in the NC diets. Phytase increased feed intake and generally improved nutrient digestibility, which resulted in an increase in digestible nutrient intake. Averaged across NC diets. PHY improved body weight. Bone-breaking strength was the most consistent predictor of Ca and P reduction. All NC diets had significantly lower bone-breaking strength than the PC. Phytase supplementation of the NC diets gave bone-breaking strengths that were comparable to the PC. Diets with PHY had the highest bioeconomic index.

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During the period from October/92 to September/94 experiments were carried out at the Seed Laboratory, FCAV/UNESP, Jaboticabal, SP, Brazil, using soybean seeds of different genotypes in order to evaluate the effect of genotype on the electrical conductivity (bulk conductivity) of soaked seeds. Seed moisture content (105 ± 3°C, 24 h), standard germination (four 50-seed samples, paper towel, 30°C), and vigor-accelerated aging (42°C, 48 h) were first determined. Undamaged soybean seeds were soaked in deionized water (four 50-seed samples, 75 ml, 25°C, 24 h) and electrical conductivity (μmhos.cm+1.g+1) was measured. Significant differences in conductivity were observed among genotypes having the same pattern of germination and vigor. The results have showed that electrical conductivity can be significantly influenced by genotype.

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The aim of this work was to observe the interaction between soil moisture and irrigation time intervals on the germination of sugarcane cv. RB785148 sets in semi-controlled conditions. One-bud sets of the variety RB785148 were germinated in ceramic pots filled with soil under a transparent PVC cover using soil humidity levels of 22, 25 and 30%, that were restored at intervals of 7, 14 and 21 days. The experiment was carried out at three different periods of the year: May-June/94; Oct.-Nov./94; and Mar.-Apr./95. The results indicate that the germination decreased mainly in function of the decrease in soil humidity, whereas irrigation interval have no statistical effect on germination. An interaction between humidity level and irrigation interval was observed. A variation of the timecourse of the germination could be observed when the results of the experiments installed at different dates were compared.

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The role of superoxide in adriamycin-induced nephropathy (single dose; i.v. 3 mg/kg) has been studied by blocking superoxide synthesis through the administration of allopurinol (500 mg/L in drinking water). In Experiment I (EI), allopurinol administration was started 3 days prior to nephropathy induction and continued until day 14. In Experiment II (EII) allopurinol administration was started 2 weeks after nephropathy induction and was maintained until the end of the experiment (26 weeks). Affected glomeruli frequency and tubulointerstitial lesion index (TILI) were determined at Weeks 2 and 4 (EI) and Week 26 (EII). In EI, and 24 h mean proteinuria in the nephrotic control group (NCG-I) differed from that of the treated nephrotic group (TNG-I) at Week 1 (TNG = 33.3 ± 6.39 mg/24 h; NCG = 59.8 ± 6.3 mg/24 h; p < 0.05) and 2 (NCG-I = 80.0 ± 17.5 mg/24h; TNG-I = 49.1 ± 8.4 mg/24 h; p < 0.05). No glomerular alterations were observed and TILI medians were not different in both nephrotic groups at week 2 (NCG-I = 1+: TNG = 1+) and 4 (NCG = 4+; TNG = 4+). In EII, NCG-II and TNG-II presented different 24 h proteinuria values only at Week 6, (136.91 ± 22.23 mg/24 h ad 72.66 ± 10.72 mg/24 h, respectively; p < 0.05). Between nephrotic groups, there was no statistical difference in the median of affected glomeruli (CNG-II = 56%; TNG-II = 48% and TILI (NCG-II = 8+; TNG-II = 9+). Thus, allopurinol was associated with a transient reduction in proteinuria and it did not alter the progression of the nephropathy.

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The investigation was carried out during May - June 1996 in Agronomical Sciences College - UNESP, Campus de Botucatu. The objective was to study the effect of seed types (carenate, alate and orbicular) and different substrates (vermiculite, sand, soil, commercial mixture and producer's mixture) on Calendula officinalis germination and seedling development. The design was in randomized blocks, with 4 replications. The germination index of the seeds was evaluated, as well as the development of aerial part and root system of the seedlings. Results showed that seed types have no relation with seedling development, therefore, germination was better on alate and orbicular seeds in C. officinalis. With reference to the substrates, the producer's mixture and the commercial mixture gave better germination and seedling development.

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Experiments on the effect of topical application of the synthetic juvenile hormone (JH-III) and of the solvent used to dissolve the hormone on the development of the wax glands of workers of Apis mellifera, were made. The results show that it was impossible to determine the effect of the juvenile hormone (JH) apart from its solvent (acetone), which also alters the developmental pattern of the gland. Most of the experiments reported in scientific literature do not consider the effect of the solvent, analyzing the results by only comparing the treatment with the hormone plus solvent to a control without any treatment. The data presented suggests that this kind of procedure compromises the evaluation of the real JH effect.

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Seasonal variations in the diurnal evolution of the global, diffuse and direct solar radiation at the surface, the clearness index, diffuse fraction and direct fraction are described in detail for the City of Sao Paulo, Brazil. The description is based on measurements of global and diffuse solar radiation carried out over 5.25 years. The diffuse component was measured with a shadow-band device. The annual evolution of the amplitude of the diurnal cycle of all radiometric parameters indicates a seasonal pattern with two distinct periods: autumn-winter and spring-summer. About 10% of the observed period was characterized by clear sky days. This seasonal variation is determined by a larger incidence of clear sky days in the autumn-winter period. Reductions of up to 10% in hourly and daily values of global radiation were observed in conjunction with an increase in particulate matter concentration on clear sky days. The pollution effect may be responsible for the discrepancy, of 16%, found between local and more regional estimates of global solar radiation in Sao Paulo. The diurnal evolution of hourly values of monthly-averaged global and diffuse solar radiation were successfully estimated by the empirical expressions derived here. Daily values of monthly-averaged global solar radiation were satisfactorily estimated using the Angstrom expression.

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By comparing the behavior of three Acromyrmex (Hymenoptera, Formicidae) species during foraging on artificial trails of different lengths, we observed the occurrence of task partitioning and its relation to the food distance from the nest. Task partitioning was verified by leaf cache formation along the trail and leaf direct transferring among workers. There was significant difference between the number of leaf fragments carried directly to the fungus chamber and those transferred direct or indirectly, via cache, depending upon the trail length. Task partitioning could be a strategy used by leaf-cutting ants that allows the workers to use food sources far from their nests.

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This paper investigates both theoretically and experimentally the effect of the location and number of sensors and magnetic bearing actuators on both global and local vibration reduction along a rotor using a feedforward control scheme. Theoretical approaches developed for the active control of beams have been shown to be useful as simplified models for the rotor scenario. This paper also introduces the time-domain LMS feedforward control strategy, used widely in the active control of sound and vibration, as an alternative control methodology to the frequency-domain feedforward approaches commonly presented in the literature. Results are presented showing that for any case where the same number of actuators and error sensors are used there can be frequencies at which large increases in vibration away from the error sensors can occur. It is also shown that using a larger number of error sensors than actuators results in better global reduction of vibration but decreased local reduction. Overall, the study demonstrated that an analysis of actuator and sensor locations when feedforward control schemes are used is necessary to ensure that harmful increased vibrations do not occur at frequencies away from rotor-bearing natural frequencies or at points along the rotor not monitored by error sensors.