907 resultados para INTERPERSONAL COMPARISONS


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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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A performance comparison between a recently proposed novel technique known as fast orthogonal frequency-division multiplexing (FOFDM) and conventional orthogonal frequency-division multiplexing (OFDM) is undertaken over unamplified, intensity-modulated, and direct-detected directly modulated laser-based optical signals. Key transceiver parameters, such as the maximum achievable transmission capacity and the digital-to-analog/analog-to-digital converter (DAC/ADC) effects are explored thoroughly. It is shown that, similarly to conventional OFDM, the least complex and bandwidth efficient FOFDM can support up to similar to 20 Gb/s over 500 m worst-case multimode fiber (MMF) links having 3 dB effective bandwidths of similar to 200 MHz X km. For compensation of the DAC/ADC roll-off, a power-loading (PL) algorithm is adopted, leading to an FOFDM system improvement of similar to 4 dB. FOFDM and conventional OFDM give similar optimum DAC/ADC parameters over 500 m worst-case MMF, while over 50 km single-mode fiber a maximum deviation of only similar to 1 dB in clipping ratio is observed due to the imperfect chromatic dispersion compensation caused by one-tap equalizers.

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The objectives of this study were: a) to determine, in a cross-sectional manner, the effect of aerobic training on the peak oxygen uptake, the intensity at O2peak and the anaerobic threshold (AnT) during running and cycling; and b) to verify if the transference of the training effects are dependent on the analized type of exercise or physiological index. Eleven untrained males (UN), nine endurance cyclists (EC), seven endurance runners (ER), and nine triathletes (TR) were submitted, on separate days, to incremental tests until voluntary exhaustion on a mechanical braked cycle ergometer and on a treadmill. The values of O2peak (ml.kg-1.min-1) obtained in running and cycle ergometer (ER = 68.8 ± 6.3 and 62.0 ± 5.0; EC = 60.5 ± 8.0 and 67.6 ± 7.6; TR = 64.5 ± 4.8 and 61.0 ± 4.1; UN = 43.5 ± 7.0 and 36.7 ± 5.6; respectively) were higher in the group that presented specific training in the modality. The UN group presented the lower values of O2peak, regardless of the type of exercise. This same behavior was observed for the AnT (ml.kg-1.min-1) determined in running and cycle ergometer (ER = 56.8 ± 6.9 and 44.8 ± 5.7; EC = 51.2 ± 5.2 and 57.6 ± 7.1; TR = 56.5 ± 5.1 and 49.0 ± 4.8; UN = 33.2 ± 4.2 and 22.6 ± 3.7; respectively). It can be concluded that the transference of the training effects seems to be only partial, independently of the index (O2peak, IO2peak or AnT) or exercise type (running or cycling). In relation to the indices, the specificity of training seems to be less present in the O2peak than in the IO2peak and the AnT.

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

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Studies of DNA damage in gastric epithelial cells of Helicobacter pylori (H. pylori)-infected patients are conflicting, possibly due to different methods used for scoring DNA damage by Comet assay. Therefore, we compared the sensitivity of visual microscopic analysis (arbitrary units-scores and comets%) and image analysis system (tail moment), in the gastric epithelial cells from the antrum and corpus of 122 H. pylori-infected and 32 non-infected patients. The feasibility of cryopreserved peripheral blood lymphocytes and whole-blood cells for DNA damage biomonitoring was also investigated. In the antrum, the levels of DNA damage were significantly higher in H. pylori-infected patients with gastritis than in non-infected patients with normal mucosa, when evaluated by image analysis system, arbitrary units and comets%. In the corpus, the comets% was not sufficiently sensitive to detect the difference between H. pylori-infected patients with gastritis and non-infected patients with normal mucosa. The image analysis system was sensitive enough to detect differences between non-infected patients and H. pylori-infected patients with mild gastritis and between infected patients with moderate and severe gastritis, in both antrum, and corpus, while arbitrary units and comets% were unable to detect these differences. In cryopreserved peripheral blood lymphocytes, the levels of DNA damage (tail moment) were significantly higher in H. pylori-infected patients with moderate and severe gastritis than in non-infected patients. Overall, our results indicate that the image analysis system is more sensitive and adequate to measure the levels of DNA damage in gastric epithelial cells than the other methods assayed. (c) 2005 Elsevier B.V. All rights reserved.

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In the present investigation we analyzed both histology and area of secretory cells from workers, virgin and physogastric queen mandibular glands of Melipona bicolor bicolor Lepeletier. The histological differences observed include the number of vacuoles present in the cell cytoplasm and the quantity and distribution of the secretion. The morphometry results demonstrated the occurrence of significative differences in the cell area values that were related to the secretory cell activity level, which is higher in the physogastric queens. Worker and queen glands have histological patterns quite similar, but the morphometric data indicated cast-specific differences, as well as differences between the queens, which were related to the posture activity.

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Follicle diameters and concentrations of follicular fluid factors were studied in the two largest follicles (F1 and F2) using F1 diameters in increments of 0.2 mm (equivalent to 4 h intervals) and extending from 7.4 to 8.4 mm (12 heifers in each of 6 groups). Changes were compared between follicles using the F2 associated with each F1-diameter group. Diameter deviation began in the 8.2-mm group as indicated by a greater (P < 0.05) diameter difference between F1 and F2 in the 8.4-mm group than in the 8.2-mm group. In the 8.0-mm group, estradiol concentrations began to increase (P < 0.05) differentially in F1 versus F2, and free insulin-like growth factor-1 (IGF-1) began to decrease differentially in F2 (P < 0.06). Combined for F1 and the associated F2, activin-A concentrations increased (P < 0.05) between the 7.6- and 8.2-mm groups and then decreased (P < 0.05). Results supported the hypothesis that estradiol and free IGF-1 concentrations simultaneously become higher in F1 than in the associated F2 by the beginning of diameter deviation. Results did not support the hypothesis that a transient elevation in activin-A is present in F1 but not in the associated F2 at the beginning of the estradiol and IGF-1 changes; instead, a mean transient elevation in activin-A occurred at this time only when data for the two follicles were combined. Comparisons between F1 and F2 also were made by independently grouping F2 and using diameter groups at 0.2-mm increments for F2 as well as for F1. In the diameter groups common to F1 and F2 (7.4, 7.6, 7.8, and 8.0 mm) there was a group effect (P < 0.003) for estradiol involving an increase (P < 0.05) beginning at the 7.6-mm group averaged over F1 and F2. For free IGF-1 concentrations, a fluctuation (a significant increase followed by a significant decrease) occurred independently in F1 between the 7.4-to 7.8-mm groups and independently in F2 between the 7.0- to 7.4-mm groups.

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SAOZ (Systeme d'Analyse par Observations Zenithales) is a ground-based UV-Visible zenith-sky spectrometer installed between 1988 and 1995 at a number of NDSC stations at various latitudes on the globe. The instrument is providing ozone and NO2 vertical columns at sunrise and sunset using the Differential Optical Absorption Spectroscopy (DOAS) technique in the visible spectral range. The ERS-2 GOME Ozone Monitoring Experiment (GOME) in 1995 was the first satellite mission to provide a global picture of atmospheric NO 2 with reasonable spatial and temporal resolution. It was then followed by SCanning ImAging spectroMeter for Atmospheric ChartographY (SCIAMACHY) onboard ENVISAT in 2002, and Ozone Monitoring Instrument (OMI) onboard EOS-AURA in 2004, with a similar capacity to monitor total NO 2. All these instruments are nadir viewing mapping spectrometers, applying the DOAS technique in the visible for deriving the NO2 total column. Here we present the results of NO2 long-term comparisons between GOME and SAOZ for the whole period of GOME operation since 1995 at all latitudes - tropics, mid-latitudes and polar regions - in both hemispheres. Comparisons are also shown with the most recently available SCIAMACHY and OMI data in 2004-2005. Overall, the daytime satellite measurements (around noon) are found consistent with sunrise ground-based data, with an average smaller difference at the tropics and mid-latitudes than in the polar areas in the summer. The agreement is even improved after correcting for the NO2 photochemical change between sunrise and the satellite overpass using a box model. However, some seasonal dependence of the difference between ground-based and satellite total NO2 still remains, related to the accuracy of photochemical simulations and the set of NO2 air mass factors used in the retrievals of both systems.

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This paper presents a practical experimentation for comparing reactive/non-active energy measures, considering three-phase four-wire non-sinusoidal and unbalanced circuits, involving five different commercial electronic meters. The experimentation set provides separately voltage and current generation, each one with any waveform involving up to fifty-first harmonic components, identically compared with acquisitions obtained from utility. The experimental accuracy is guaranteed by a class A power analyzer, according to IEC61000-4-30 standard. Some current and voltage combination profiles are presented and confronted with two different references of reactive/non-active calculation methodologies; instantaneous power theory and IEEE 1459-2010. The first methodology considers the instantaneous power theory, present into the advanced mathematical internal algorithm from WT3000 power analyzer, and the second methodology, accomplish with IEEE 1459-2010 standard, uses waveform voltage and current acquisition from WT3000 as input data for a virtual meter developed on Mathlab/Simulink software. © 2012 IEEE.

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Objective: To compare immediate and staged approach implant placement in circumferential defects treated with deproteinized bovine bone mineral (DBBM); hidroxyapatite/tricalcium phosphate (HA/TP); autogenous bone (Ab); and coagulum (Cg); upon implant stability, osseointegration and alveolar crest maintenance. Materials and methods: Six dogs underwent extractions of lower premolars, bilaterally. Twelve weeks later four bone defects (6 mm wide/4 mm long) were drilled at one side and randomly filled with DBBM; HA/TP; Ab; and Cg, respectively, and left to heal (staged approach). Eight weeks later one implant (Osseospeed™, AstraTech) was placed in experimental sites. At the same session four defects were drilled on contra-lateral side and implants were inserted immediately after biomaterials grafting (immediate approach). Animals were euthanized 8 weeks later. Implant stability was measured by resonance frequency analysis (RFA) at installation and after sacrifice. Ground sections were prepared for bone contact (BIC); bone area (BA); distance implant shoulder-bone crest (IS-C); distance implant shoulder first bone contact (IS-B); and areas occupied by soft tissue. Results: The BA and BIC were superior in the staged approach. The Cg exhibited higher BIC and BA as compared with other materials at the total implant body (P = 0.004 and 0.012, respectively). The DBBM, HA/TP and Ab groups rendered similar BA and BIC. The immediate approach resulted in less crest resorption compared to staged approach. The biomaterials did not affect the IS-C and IS-B measurements. Particles area tended to be higher in DBBM group than HA/TP (P = 0.15), while soft tissue infiltrate was higher in DBBM group when used in the immediate approach (P = 0.04). The RFA indicated gain in stability in the staged approach (P = 0.002). The correlation test between RFA vs. BIC and BA demonstrated inferior stability for DBBM group in immediate approach (P = 0.01). Conclusions: Implants placed in healed defects resulted in better stability as a consequence of higher BIC and BA. The Cg alone rendered increased BIC compared to other materials in both approaches. Immediate approach should be preferable to staged approach in terms of alveolar crest maintenance. The BIC and BA values did not vary between micro and macro-threads in this experimental model. Implants installed in sites filled with DBBM in immediate approach were less stable. © 2011 John Wiley & Sons A/S.

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

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The biological characteristics of Aedes aegypti (Diptera, Culicidae), which is a vector of dengue and yellow fever, make this organism a good model for studying population structure and the events that may influence it under the effect of human activity. We assessed the genetic variability of five A. aegypti populations using RAPD-PCR technique and six primers. Four populations were from Brazil and one was from the USA. A total of 165 polymorphic DNA loci were generated. Considering the six primers and the five populations, the mean value of inter-population genetic diversity (Gst) was 0.277, which is considered high according to the Wright classification. However, pairwise comparisons of the populations gave variable Gst values ranging from 0.044 to 0.289. This variation followed the population's geographic distance to some extent but was also influenced by human activity. The lowest Gst values were obtained in the comparison of populations from cities with intensive commercial and medical contacts. These mosquito populations were previously classified as insecticide resistant, susceptible, or with decreased susceptibility; this parameter apparently had an effect on the Gst values obtained in the pairwise comparisons. ©FUNPEC-RP.

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A visual methods study was conducted with 16 at-risk youth living in a mid-sized Brazilian city. In this study, we focus on data obtained from four of those youth who were working adolescents, aged 13-15, and identify contextually specific protective processes associated with resilience. Through a reciprocal process of collaborative research that included observation, photo elicitation, video recording of a 'day in the life' of each youth, and semi-structured interviews, youth and researchers co-constructed an understanding of adaptive coping in a particularly challenging social environment. By employing techniques from grounded theory to analyze the data, we identified a pattern of protagonism among these youth that enabled them to maintain well-being despite exploitation as working children. This conceptualization of protagonism as a protective process has implications for human service workers who intervene to improve the living conditions of working children. © 2013 Taylor & Francis.