RCAAP Repository

O cálculo da luminescência em um semicondutor de gap direto e feito através de dois métodos bastante utilizados na literatura espelicializada na área, são tomados para uma simples comparação dos resultados teóricos obtidos. No primeiro caso, o método da equação de movimento da função de Green que, representa a interação entre o campo excitante, no caso um LASER potente e, a amostra semicondutora e desenvolvido com uso do desacoplamento RPA. A função diel étrica e obtida desse cálculo. No segundo a aplicação da teoria diagramática de perturbação, como um método mais rigoroso e sofisticado, no entanto de domínio mais difícil, e desenvolvido com o mesmo propósito do anterior. Com mais elegância obtemos o c álculo da luminescência. Os dois métodos são apresentados com alguma completude. Ao nal comparamos os dois resultados.

The phase diagram of an Ising metamagnet in an uniform magnetic field and in a random magnetic field is studied using a mean field theory derived from Bogoliubov variational principle. The phase diagram displays tricritical behavior and reentrance phenomenon for determined values of the random magnetic field above a certain critical value. The reentrance phenomenon is due to the competition between the other interactions ferromagnetic, anti-ferromagnetic, uniform magnetic field and the random magnetic field. In particular, if the model exhibits a first-order transition in zero random field, then a bimodal distribution never destroys this first-order transition, in contradiction to the case of a trimodal distribution.

Nonlinear fiber Bragg gratings has been considered since the end of last century for applications in optical communications and sensor techniques. The investigation of ultrashort pulses in linear Bragg gratings, however has been considered in the last few years due the development of specifical numerical techniques to solve this problem. In the present work an analytical and numerical study of the reflection and transmission characteristics of nonlinear Bragg gratings was done. For the first time, it has been considered periodic variations of the nonlinearity in that devices operating in the continuous wave regime, leading to a new class of nonuniform gratings. It was extensively investigated the bi- and multistable characteristics in these nonlinear fiber Bragg gratings. Also, for the first time, the numerical study of ultrahsort pulses (»1 ps) incident in nonlinear gratings was done. The focus was the input pulse intensity dependence on that gratings. Also, the depedences in the time shapes of grating index modulation depth and nonlinear index were studied. Apodized gratings were considered since they are of fundamental importance in modern communications systems.

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This study investigates the impacts of the government income transfers on laborforce participation using data from the 1991 and 2000 Brazilian Censures. The determinants of labor force participation are evalualed by means of a random utility model.It is observed that the government income transfers have a strong impact on individual’s willingness to join the labor force. Other variables that affected significantly the labor force participation are geographic localization, education and fertility.

This article is the premise of the relationship between economic growth recorded in the first half of the decade and the current behavior to income distribution. Then emphasis is on checking in Brazilian regions, where does in fact growth is more "pro-poor" in urban than in rural areas. The methodology of analysis employs the technical developed by Kakwani, Khandker and Son (2004), which uses the measures of Headcount ratio (P0), Poverty gap ratio (P1) and Severity of Poverty (P2) quantifying-qualifying issue growth as "pro-poor" or not one. Results show predominance the core of economic growth pro-poor, and suggesting that poverty reduction was present in all regions and sectors, but its intensity is not enough to believe a reduction of distance that separates the region northeast of other regions.

COUTINHO, Fernanda. Vestígios da infância de um escritor romântico. Revista de Letras, Fortaleza, v. 29, pt. 2, p.42-46, 2009.

PELOGGIO, Marcelo Almeida. O homem por trás das cores. Revista de Letras, Fortaleza, v. 1, n. 29, pt. 2, p. 69-74, 2009.

PRIORE, Mary Del. Conversas entre história e literatura: o exemplo de Alencar. Revista de Letras, Fortaleza, v. 1, n. 29 , pt. 2, p. 92-95, 2009.

MORAES, Vera Lúcia Albuquerque de. José de Alencar e a organização do campo intelectual do segundo império. Revista de Letras, Fortaleza, v. 1, n. 29, pt. 2 , p. 114-120, 2009.

MENDES, Danielle. Quadros em movimento, esquadros da memória: memória, imagem e palavra em José de Alencar. Revista de Letras, Fortaleza, v.1, n. 29, pt. 2, p. 19-25 2009.

BARBOSA, Ivone Cordeiro. História social do sertão na obra de José de Alencar. Revista de Letras, Fortaleza, v. 1, n. 29, pt. 2, p. 47-53, 2009.

PINTO, Maria Cecília de Moraes. Alencar e o tamanho da sociedade fluminense. Revista de Letras, Fortaleza, v. 1, n. 29, pt. 2 , p. 83-88, 2009.

SILVA Odalice de Castro. Outra “nota à Iracema”: o corpo escrito de Martim.Revista de Letras, Fortaleza, v. 1, n. 29, pt. 2, p. 101-105, 2009.

LAJOLO, Marisa. José de Alencar,um criador de autores e de leitores. Revista de Letras, Fortaleza, v. 1, n. 29, pt. 2, p. 89-91, 2009.

Morais, Apiano F.; Andrade Jr., José S.. Escoamento de fluidos complexos e transporte de partículas em geometrias irregulares. Fortaleza, 2011. 131p. Tese de Doutorado — Departamento de Física, Universidade Federal do Ceará.

The interactions between innate and acquired immune responses participate in the pathophysiology of the autoimmune diseases. Though infections are associate with the development of the chronic arthritis it is possible that exposure to some germs as helminthes and fungi influences potentially the prevalence and/or gravity of the immune diseases. Lectins derivate of the plants can modulate the inflammation by action in receptors of the innate response. We investigated the effect of extracts from Ascaris suum (AS), Coccidioides posadasii (CS) and a lectin isolated from Dioclea violacea (Dviol) in zymosan-induced arthritis (ZyA). Wistar rats and Swiss mice received 1 mg or 0.1 mg zymosan intra-articular (i.art.), respectively. Groups were pretreated (30 min) with AS (0.25 - 2.5 mg/animal; i.p. or p.o.) CP (1 - 100 µg/animal; i.art. i.p. or p.o) or Dviol (0.3 - 30 µg; i.art. or 1 - 6 mg/kg; i.v.). Non-treated group (NT) received Zy (i.art.) and the vehicle. Naive animals received just saline (i.art.) and the vehicle. The hypernociception was evaluated through articular incapacitation test in s/1min. The joint exudate was used for evaluation of cell influx (CI), nitrite and cytokine levels. The synovium was used for histopatology. The glycosaminoglycan (GAG) content of the cartilage was quantificated for the measured of the structural damage. The AS extract both i.p. and p.o. significantly and dose-dependently inhibited CI and hypernociception in ZyA as compared to NT (P<0.01) as well as reverted articular damage assessed by quantification of the GAG and by synovitis observed in the histology. The administration of the AS extract reduced significantly levels of nitrite, interleukin-1β (IL-1β) and IL-10, but not tumor necrosis factor alpha (TNF-α) as compared to NT. In mice, it reduced IL-10 but not IL-1β and TNF- α. The treatment with CP extract both i.p. and p.o. inhibited hypernociception and CI in ZyA as compared to NT, but not reverted articular injury measured by GAG and histology. The administration of the Dviol in naïve animals promoted CI significant, though just the highest dose (30 g) promoted hypernociception. In ZyA, Dviol (i.art.) reduced the CI and hypernociception dose-dependently (P<0.01). The administration of Dviol (i.v.) significantly reduced both the hyperalgesia and CI in ZyA as compared to NT (P<0.01). The effect of the Dviol was reverted when it was pre-incubated with mannose (1M). The date show that AS extract promote functional improve and protect of the articular damage in ZyA that are associate with reduction of the NO and cytokine (i.art.) liberation. This effect is species independent and functions orally. An extract of the fungi CP has anti-inflammatory activity in ZyA. A lectin isolated of the Dviol reduces CI and hypernociception in ZyA probably by coupling the mannose receptor. Together the results show that substances that act in receptors of the innate response modulate the immunomediate articular inflammation.

Reactive oxygen species (ROS) and nitrogen (RNS) promote tissue destruction in inflammatory diseases such as rheumatoid arthritis. However, agents that activate ROS production by NADPH oxidase reduce inflammation in experimental models. Considering the controversial participation of via NO-cGMP in nociception, inhibitors of phosphodiesterase-5 have controversial role in models of pain. In this study, it was investigated the effect of phytol, an activating of NADPH oxidase, and tadalafil, a phosphodiesterase-5 inhibitor, in models of zymosan-induced arthritis (ZyA) and Zy-induced peritonitis as well as osteoarthritis by anterior cruciate ligament transection (ACLT) and acetic acid writhing. In ZyA, rats and mice received 1 mg and 100 µg zymosan intra-articular (i.art.), respectively. In peritonitis or writhing, mice received 100 µg of Zy or acetic acid intraperitoneal (i.p.), respectively. In osteoarthritis, rats underwent ACLT. Rats received phytol subcutaneous (s.c) 30 min – 8 d before ZyA or tadalafil orally (p.o.) 2 h after Zy. Other rats received SIN-1 (i.art.), ODQ (i.art.) or naloxone (i.p.) 1.5 – 2 h after Zy. Mice received phytol s.c. 1 – 24 h before Zy i.art.. Other mice received phytol i.art. 1 h before or 1.5 h after Zy. In peritonitis or writhing, phytol s.c. was injected 30 min – 24 h before Zy or acetic acid, respectively. In osteoarthritis, it was done one s.c. phytol administration 5 d before and 35 d after ACLT or tadalafil p.o. from 4 – 7 d after ACLT. Control groups received Zy i.art. or i.p. or acetic acid or were submitted to ACLT. The hypernociception was assessed by articular incapacitation test recorded as paw elevation time - PET. Cell influx (CI) was quantified in joint lavage after 6 h or 7 d of ZyA and in peritoneal lavage after 4 h of peritonitis. NO, IL-1, TNF-α, IL-10 and CINC-1 were measured in acute articular supernatant in rats while cartilage glycosaminoglycans (GAGs) were quantified after 7 d of ZyA in rats. Results were expressed as mean ± SEM, submitted to ANOVA and Tukey test or to Student’s t test (P <0.05). In writhing, data were expressed as median and submitted to the Kruskal-Wallis test (P<0.05). In ZyA, systemic (s.c.) and prophylactic administration of phytol decreased acute CI, independent of dose and time of administration, in mice. Local (i.art.) prophylactic or therapy injection of phytol decreased significantly CI in mice submitted to ZyA. Similar to the acute phase, phytol reduced significantly chronic CI. In ZyA in rats, phytol decreased acute and chronic CI as well as PET. As to GAGs, there was significant increase by phytol, reaching a level similar to naive animals. In peritonitis or writhing, phytol decreased CI or number of writhing, respectively, regardless of administration time. In osteoarthritis, phytol decreased significantly PET on days 1, 7, 9 and 11 as well as the peak between 4th and 7th d after ACLT. NO, IL-1, TNF-α and IL-10 were reduced in ZyA too. As tadalafil, there was decreased acute IC and PET, in a dose-dependent, in ZyA in rats. ODQ, administered prior tadalafil, reversed tadalafil effect about CI and PET in ZyA, that didn’t happen with a prior injection of naloxone. Tadalafil reduced TNF-α and IL-10 in ZyA and PET in osteoarthritis. The results show that phytol promotes anti-inflammatory and antinociceptive effects species, stimulus, tissue and route of administration independent. These actions are associate with the local release of NO and cytokines. In parallel, tadalafil has similar anti-inflammatory and antinociceptive effects associated with the lock on the local release of TNF. These findings suggest that activators of NADPH oxidase, possibly from compounds in the diet, modify the natural history of inflammatory arthropathy. The antinociceptive effect of phosphodiesterase-5 inhibitors should be explored, since these compounds are progressive indication in inflammatory diseases that occur with vascular damage and hypoxia.

In this thesis, we study complete space-like hypersurfaces immersed in semi-Riemannian manifolds, satisfying some conditions on their higher-order mean curvatures in order to get Bernstein-type results. Analytical tools we use are some versions of the maximum principle. When the ambient space is a generalized Robertson-Walker spacetime which is supposed to obey the strong null convergence condition, we establish new characterizations of totally geodesic spacelike hypersurfaces. Furthermore, we obtain a lower estimate the minimum index of relative nullity when the space-like hypersurface is r-maximal, or when there are two consecutive higher-order mean curvatures that do not change sin. We also obtain rigidity results and new characterizations of totally umbilical hypersurfaces, assuming they have some constant higher-order mean curvature, and that the ambient space is a spacetime Robertson-Walker obeying the null convergence condition. These results are applied to the de Sitter and anti-de Sitter spaces. Finally, we prove a Bernstein-type theorem for constant mean curvature complete hypersurfaces immersed in a riemannian product.

Disrupted sleep and nocturnal hypoxia are common in cystic fibrosis (CF). However, the predictors of nocturnal hypoxia in CF are still controversial. In order to identify the risk factors for nocturnal desaturation and sleep disturbances, we carried out a clinical and polysomnographic investigation of CF patients. We studied 30 clinically stable CF cases with clinical lung disease (mean age=12.8; mean forced expiratory volume in 1 second FEV1=65.2), 10 CF cases without significant lung disease (mean age=13.3; mean FEV1=99.8), and 20 controls (mean age=15.5). Patients were evaluated by spirometry, 6-min walk test (6MWT), the Shwachman–Kulczycki (S–K) score, and full overnight polysomnography. Cases with clinical lung disease had lower body mass index, forced vital capacity, and S–K scores. During sleep, five CF cases with clinical lung disease (15%) had SaO2 <90% during more than 30% of total sleep timeand 11 cases (36.6%) had a nadir SaO2 below 85%. FEV1 values for CF cases with clinical lung disease were related to nadir SaO2 (P<0.03) and to mean oxygen saturation SaO2 (P=0.02). A receiver operating characteristic (ROC) analysis determined FEV1 at 64% to be predictive of nocturnal desaturation as defined by minimum SaO2 <85% (sensitivity=92.3%; specificity=77.3%) or SaO2<90% for 30% of sleep time (sensitivity=81.8%; specificity=85.2%). Frequency of impaired sleep was not different in CF cases with (N=5) and without significant lung disease (N=2, P=0.53). Sleep architecture was not significantly different between the two groups. Sleep apnea was present in three CF cases with clinical lung disease and in one case without significant lung disease. In summary, desaturation during sleep can be predicted by FEV1<64%with good sensitivity and specificity. There are no significant differences in sleep architecture between clinically stable CF cases with and without significant lung disease. The recognition of biological markers that can predict clinical deterioration in cystic fibrosis (CF) is a key issue in everyday care of these patients. The (S-K) scores and (FEV1) have been considered the best independent predictors of impairment/disability. The aim of this study was to evaluate the role of high-resolution computed tomography of the chest (HRCT) and the use of the Bhalla score in the detection of functional disability in CF. Cases of both genders, aged older than six years, with CF clinically stable were studied with spirometry, basal oxygen saturation SpO2, the 6MWT, HRCT and the S-K score. Twenty-five patients (15 male, mean age 14.2±5.6) with FEV1 (range 28.6-98.0; mean 62.5±21.8) were studied. Nine patients had severe/moderate respiratory insufficiency (4079). Bronchiectasis was the most frequent finding. Peribronchial thickening, mucus plugging and emphysema, despite being less severe, were also commonly observed. None of the cases presented bullae. Total scores of CT abnormalities varied from 7 to 25 (13.8±4.4). The ROC curve showed the high sensitivity/specificity for Bhalla and S-K scores in the prediction of clinical disability as measured by the FEV1. By comparison, the Bhalla scores showed higher sensitivity than the S-K scores. SpO2 and the 6MWT were not good predictors of disability as measured by functional pulmonary tests. Melatonin, a natural hormone secreted by the pineal gland, has an important function in the synchronization of circadian rhythms, including the sleep–wake cycle, and has been shown to possess significant anti-oxidant properties. To evaluate the effects of exogenous melatonin on sleep and inflammation and oxidative stress markers in CF we conducted a randomized double-blind placebo controlled study initially involving 20 patients with CF. One case failed to conclude the study. All subjects were clinically stable when studied and without recent infectious exacerbation or hospitalization in the last 30 days. Groups were randomized for placebo (N= 10; mean age 12.10±6.0) or melatonin 3.0 mg (N=9; mean age 16.62±8.26) during 21 days. Actigraphy was performed during 6 days before start of medication and in the third week (days 14 to 20) of treatment. Isoprostane and nitrite levels were determined in exhaled breath condensate (EBC) at baseline (day 0) and after treatment (Day 21). Melatonin improved sleep efficiency (p=0.01) and tended to improve sleep latency (p= 0.08). Melatonin reduced EBC nitrite (p=0.01) but not isoprostane. In summary, melatonin administration reduces nitrite levels in EBC and improves sleep measures in clinically stable CF patients.