30 resultados para Lino

em Biblioteca Digital da Produção Intelectual da Universidade de São Paulo


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This theoretical proposal applies evolutionary aesthetic, animal signalling and sexual selection to understand our artistic cognition, especially rock art aesthetics. Iconographic motifs, universally found in rock art, indicate which set of pre-artistic aesthetic psychological bias has been co-opted to catch the viewer`s attention. The co-evolutionary process of sexual selection could have shaped the design features of both rock art images and their aesthetic cognition by conferring mutual benefits on both producers, via manipulation, and receivers, via information extraction. We show some strategic techniques identified in rock art and art that indicate the occurrence of this co-evolution between producers and receivers.

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We report on the generation of tunable light around 400 nm by frequency-doubling ultrashort laser pulses whose spectral phase is modulated by a sum of sinusoidal functions. The linewidth of the ultraviolet band produced is narrower than 1 nm, in contrast to the 12 nm linewidth of the non-modulated incident spectrum. The influence of pixellation of the liquid crystal spatial light modulator on the efficiency of the phase-modulated second harmonic generation is discussed.

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The excited-state dynamics of free-base meso-tetrakis(sulfonatophenyl) porphyrin J-aggregates obtained by the Z-scan technique in femto- and picosecond time scales, along with UV-Vis spectroscopy and flash photolysis is reported. Besides obtaining the S-1 state lifetime, the discrimination between internal conversion and intersystem crossing nonradiative processes from that state was also possible, and their rates and respective quantum yields were found. The aggregates present reverse saturable absorption at 532 nm for both singlet and triplet excited states. The data shown is important for several applications such as optical limiting, photodynamic therapy and others. (C) 2011 Elsevier B.V. All rights reserved.

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Objective. To determine the influence of socioeconomic factors on disease activity in a Latin American (LA) early rheumatoid arthritis (RA) multinational inception cohort at baseline. Methods. Clinical evaluation, ethnicity, socioeconomic status (SES), 4-variable Disease Activity Score in 28 joints using the erythrocyte sedimentation rate (DAS28-ESR), Health Assessment Questionnaire (HAQ) disability index (DI), and erosions were recorded in 1,093 patients with early RA (<1 year from onset). Multivariate analyses evaluated influences of sex, age, marital status, education, medical coverage, SES, and ethnicity on HAQ DI, DAS28-ESR, and presence of erosions. Results. Ethnicities included 43% Mestizo, 31% Caucasian, 19% African LA, 4% Amerindian, and 3% other. Fifty-eight percent were of low/low-middle SES, 42% had <8 years of education, 21% had no medical coverage, median disease duration was 6 months (25th, 75th percentiles 4, 9 months), median HAQ DI score was 1.25 (25th, 75th percentiles 0.63, 2.00), median DAS28-ESR score was 6.2 (25th, 75th percentiles 4.9, 7.2), and 25% had erosions. Women and Mestizos, African LA, and Amerindians had earlier onset than men or Caucasians (P < 0.01). When adjusted by country, the analysis of covariance model showed that low/low-middle SES, female sex, partial coverage, and older age were associated with worse HAQ DI scores; only low/low-middle SES was associated with higher DAS28 scores. Statistically significant differences were found in HAQ DI and DAS28 scores between countries. When excluding country, low/low-middle SES, female sex, and no coverage were associated with worse HAQ DI and DAS28 scores, whereas separated/divorced/widowed status was associated with worse HAQ DI scores and age was associated with worse DAS28 scores. Logistic regression showed that older age, no coverage, and the Amerindian and other ethnic groups were associated with erosions. Conclusion. We compared early RA patients from the main LA ethnic groups. Our findings suggest that low/low-middle SES is important in determining disease activity. A more genetic-related background for erosions is possible.

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The few studies that have investigated judgments of time have suggested that the memory of duration is distorted more for emotional events than for neutral events, while in contrast there is abundant evidence that other aspects of memories of emotional events are more accurate. To reconcile this apparent discrepancy, we used a procedure in which the participants learned a standard duration over several trials under three emotional conditions: a threatening, a nonthreatening, and a neutral control condition. They were then tested either immediately or 24 h after learning. In this test phase, they had to indicate whether presented comparison durations were or were not the same as the previously learned standard duration. We found that durations were recalled better in the emotional than in the neutral condition, and that this occurred to a greater extent in the threatening than in the nonthreatening condition. Arousing emotions thus enhanced temporal memory, just as they enhance memory for other aspects of emotional events.

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This paper reports the synthesis of Au nanoparticles by 30-fs pulses irradiation of a sample containing HAuCl4 and chitosan, a biopolymer used as reducing agent and stabilizer. We observed that it is a multi-photon induced process, with a threshold irradiance of 3.8 x 10(11) W/cm(2) at 790 nm. By transmission electron microscopy we observed nanoparticles from 8 to 50 nm with distinct shapes. Infrared spectroscopy indicated that the reduction of gold and consequent production of nanoparticles is related to the fs-pulse induced oxidation of hydroxyl to carbonyl groups in chitosan. (C) 2011 Optical Society of America

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Although mangroves represent ecosystems of global importance, the genetic diversity and abundance of functional genes that are key to their functioning scarcely have been explored. Here, we present a survey based on the nifH gene across transects of sediments of two mangrove systems located along the coast line of Sao Paulo state (Brazil) which differed by degree of disturbance, i.e., an oil-spill-affected and an unaffected mangrove. The diazotrophic communities were assessed by denaturing gradient gel electrophoresis (DGGE), quantitative PCR (qPCR), and clone libraries. The nifH gene abundance was similar across the two mangrove sediment systems, as evidenced by qPCR. However, the nifH-based PCR-DGGE profiles revealed clear differences between the mangroves. Moreover, shifts in the nifH gene diversities were noted along the land-sea transect within the previously oiled mangrove. The nifH gene diversity depicted the presence of nitrogen-fixing bacteria affiliated with a wide range of taxa, encompassing members of the Alphaproteobacteria, Betaproteobacteria, Gammaproteobacteria, Firmicutes, and also a group of anaerobic sulfate-reducing bacteria. We also detected a unique mangrove-specific cluster of sequences denoted Mgv-nifH. Our results indicate that nitrogen-fixing bacterial guilds can be partially endemic to mangroves, and these communities are modulated by oil contamination, which has important implications for conservation strategies.

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This work reports on the spectral dependence of both nonlinear refraction and absorption in lead-germanium oxide glasses (PbO-GeO2) containing silver nanoparticles. We have found that this material is suitable for all-optical switching at telecom wavelengths but at the visible range it behaves either as a saturable absorber or as an optical limiter. (C) 2012 Optical Society of America

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Hydroquinone (HQ) is the main oxidative substance in cigarette smoke and a toxic product of benzene biotransformation. Although the respiratory tract is an inlet pathway of HQ exposure, its effect on airway muscle responsiveness has not been assessed. We thus investigated the effects of low dose in vivo HQ-exposure on tracheal responsiveness to a muscarinic receptor agonist. Male Swiss mice were exposed to aerosolised 5% ethanol/saline solution (HQ vehicle; control) or 0.04 ppm HQ (1 h/day for 5 days) and tracheal rings were collected 1 h after the last exposure. HQ exposure caused tracheal hyper-responsiveness to methacholine (MCh), which was abolished by mechanical removal of the epithelium. This hyperresponsiveness was not dependent on neutrophil infiltration, but on tumour necrosis factor (TNF) secretion by epithelial cells. This conclusion was based on the following data: (1) trachea from HQ-exposed mice presented a higher amount of TNF, which was abrogated following removal of the epithelium; (2) the trachea hyperresponsiveness and TNF levels were attenuated by in vivo chlorpromazine (CPZ) treatment, an inhibitor of TNF synthesis. The involvement of HQ-induced TNF secretion in trachea mast cell degranulation was also demonstrated by the partial reversion of tracheal hyperresponsiveness in sodium cromoglicate-treated animals, and the in vivo HQ-exposure-induced degranulation of trachea connective tissue and mucosal mast cells, which was reversed by CPZ treatment. Our data show that in vivo HQ exposure indirectly exacerbates the parasympathetic-induced contraction of airway smooth muscle cells, mediated by TNF secreted by tracheal epithelial cells, clearly showing the link between environmental HQ exposure and the reactivity of airways. (C) 2012 Elsevier Ireland Ltd. All rights reserved.

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Mangrove ecosystems are tropical environments that are characterized by the interaction between the land and the sea. As such, this ecosystem is vulnerable to oil spills. Here, we show a culture-independent survey of fungal communities that are found in the sediments of the following two mangroves that are located on the coast of Sao Paulo State (Brazil): (1) an oil-spill-affected mangrove and (2) a nearby unaffected mangrove. Samples were collected from each mangrove forest at three distinct locations (transect from sea to land), and the samples were analyzed by quantitative PCR and internal transcribed spacer (ITS)-based PCR-DGGE analysis. The abundance of fungi was found to be higher in the oil-affected mangrove. Visual observation and correspondence analysis (CA) of the ITS-based PCR-DGGE profiles revealed differences in the fungal communities between the sampled areas. Remarkably, the oil-spilled area was quite distinct from the unaffected sampling areas. On the basis of the ITS sequences, fungi that are associated with the Basidiomycota and Ascomycota taxa were most common and belonged primarily to the genera Epicoccum, Nigrospora, and Cladosporium. Moreover, the Nigrospora fungal species were shown to be sensitive to oil, whereas a group that was described as "uncultured Basidiomycota" was found more frequently in oil-contaminated areas. Our results showed an increase in fungal abundance in the oil-polluted mangrove regions, and these data indicated potential fungal candidates for remediation of the oil-affected mangroves.

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Asthma is an allergic lung disease can be modulated by drugs that modify the activity of central nervous system (CNS) such as amphetamine (AMPH). AMPH is a highly abused drug that exerts potent effects on behavior and immunity. In this study we investigated the mechanism involved in the effects of long-term AMPH treatment on the increased magnitude of allergic lung response. We evaluated mast cells degranulation, cytokines release, airways responsiveness and, expression of adhesion molecules. Male Wistar rats were treated with AMPH or vehicle (PBS) for 21 days and sensitized with ovalbumin (OVA) one week after the first injection of vehicle or AMPH. Fourteen days after the sensitization, the rats were challenged with an OVA aerosol, and 24 h later their parameters were analyzed. In allergic rats, the treatment with AMPH exacerbated the lung cell recruitment due increased expression of ICAM-1, PECAM-1 and Mac-1 in granulocytes and macrophages recovered from bronchoalveolar lavage. Elevated levels of IL-4, but decreased levels of IL-10 were also found in samples of lung explants after AMPH treatment. Conversely, the ex-vivo tracheal hyper-responsiveness to methacholine (MCh) was reduced by AMPH treatment, whereas the force contraction of tracheal segments due to in vitro antigen challenge remained unaltered. Our findings suggest that lung inflammation and airway hyper-responsiveness due to OVA challenge are under the distinct control of AMPH during long-term treatment. Our data strongly indicate that AMPH positively modulates allergic lung inflammation via the increase of ICAM-1, PECAM-1, Mac-1 and IL-4. AMPH also abrogates the release of the anti-inflammatory cytokine IL-10. (c) 2012 Elsevier B.V. All rights reserved.

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Este estudo verificou se emoções percebidas durante uma escuta musical influenciam a percepção temporal. Músicos e não músicos foram submetidos a tarefas de escuta de trechos musicais do repertório erudito ocidental com 20 segundos de duração cada um e tarefas de associação temporal de cada trecho ouvido a durações padrões, que variavam de 16 a 24 segundos. Os trechos musicais empregados eram representativos de uma dentre as categorias emocionais Alegria, Tristeza, Serenidade ou Medo / Raiva. Uma análise de variância mostrou que, enquanto os não músicos apresentaram subestimações temporais associadas a pelo menos um trecho musical de cada uma das categorias emocionais, os músicos subestimaram todos os trechos musicais tristes, relacionados às características de baixo arousal e valência afetiva negativa.

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Background. Intestinal ischemia and reperfusion (I/R) is a documented cause of acute lung injury (ALI) and systemic inflammation. We previously reported that obstruction of thoracic lymphatic flow during intestinal I/R blunts pulmonary neutrophil recruitment and microvascular injury and decreases the systemic levels of tumor necrosis factor. Here, we consider the existence of a gut-lung axis promoting the induction of systemic inflammation, whereby drained intestinal lymph stimulates lung expression of adhesion molecules and matrix components and generation of inflammatory mediators. Material and Methods. Upon administration of anesthesia, male Wistar rats were subjected to occlusion of the superior mesenteric artery for 45 min, followed by 2 h of intestinal reperfusion (I/R); groups of rats were subjected to I/R with or without thoracic lymphatic duct ligation immediately before the procedure. The non-manipulated rats were used to investigate basal parameters. Results. Obstruction of thoracic lymphatic flow before intestinal I/R decreased the ability of cultured lung tissue explants to release IL-1 beta, IL-10, and VEGF. In contrast, lymphatic obstruction normalized the elevated lung expression of PECAM-1 caused by intestinal I/R. On the other hand, lung E-selectin expression was significantly reduced, whereas fibronectin expression and collagen synthesis were not affected. Lymph levels of LTB4 and TXB2 were found to be significantly increased. Conclusions. These data suggest that lymph factors drained from the intestine during ischemic trauma stimulate the lung to generate inflammatory mediators and alter the expression of adhesion molecules. Disturbances in lung homeostasis mediated by lymph might contribute to the spread of inflammatory processes, thereby accounting for the systemic inflammation induced by intestinal I/R. (C) 2012 Elsevier Inc. All rights reserved.

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Prevalence of Toxoplasma gondii infection in 510 free-range (FR) chickens (380 from 33 small farms, and 130 from a slaughter house for FR chickens) from Espirito Santo state, southeastern Brazil, was investigated. Antibodies to T. gondii were sought using commercial indirect haemagglutination (IHAT, Imuno-HAI Toxo (R), Wama Diagnostica, Sao Paulo, Brazil, cut-off 1:16) and the modified agglutination test (MAT, cut-off 1:25) tests. Attempts were made to isolate viable T. gondii from seropositive chickens by bioassay in mice. Pooled samples of brain, heart and quadriceps muscle of one thigh (total 40 g) from 64 chickens with IHAT titers of >= 1:16 were minced, digested in pepsin and bioassayed in mice. Antibodies to T. gondii were found in 40.4% (206/510) FR chickens by IHAT (titer >= 1:16) and 38.8% (198/510) by MAT (titer >= 1:25); concordance between IHAT and MAT was 81.6% (kappa index = 0.614). Viable T. gondii was isolated (designated TgCkBr234-281) from 48 of 64(75%) seropositive (IHAT titers >= 1:32) FR chickens. Most isolates of T. gondii were virulent for mice; 100% of mice inoculated with 44 of 48 isolates died of toxoplasmosis within 30 days post inoculation (p.i). An epidemiological investigation revealed that people living in rural areas have little knowledge about the parasite and about the risk of acquiring it from raw meat. Results indicated that the locally available IHAT was useful for screening of chicken sera for T. gondii antibodies. (C) 2012 Elsevier B.V. All rights reserved.

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Evidence from appetitive Pavlovian and instrumental conditioning studies suggest that the amygdala is involved in modulation of responses correlated with motivational states, and therefore, to the modulation of processes probably underlying reinforcement omission effects. The present study aimed to clarify whether or not the mechanisms related to reinforcement omission effects of different magnitudes depend on basolateral complex and central nucleus of amygdala. Rats were trained on a fixed-interval 12 s with limited hold 6 s signaled schedule in which correct responses were always followed by one of two reinforcement magnitudes. Bilateral lesions of the basolateral complex and central nucleus were made after acquisition of stable performance. After postoperative recovery, the training was changed from 100% to 50% reinforcement schedules. The results showed that lesions of the basolateral complex and central nucleus did not eliminate or reduce, but interfere with reinforcement omission effects. The response from rats of both the basolateral complex and central nucleus lesioned group was higher relative to that of the rats of their respective sham-lesioned groups after reinforcement omission. Thus, the lesioned rats were more sensitive to the omission effect. Moreover, the basolateral complex lesions prevented the magnitude effect on reinforcement omission effects. Basolateral complex lesioned rats showed no differential performance following omission of larger and smaller reinforcement magnitude. Thus, the basolateral complex is involved in incentive processes relative to omission of different reinforcement magnitudes. Therefore, it is possible that reinforcement omission effects are modulated by brain circuitry which involves amygdala. (C) 2012 Elsevier B.V. All rights reserved.