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This case report describes a technique that uses a palatal mucosal graft and an acrylic resin postoperative stent in an attempt to increase the layer of keratinized tissue around osseointegrated implants in an atrophic mandible. During second-stage surgery a split-thickness labial flap is reflected and apically repositioned by being sutured onto the periosteum and connective tissue. A palatal mucosal graft is then sutured onto the recipient site. The stent is worn for at least 4 weeks following surgery. This procedure helps to eliminate mobility of the mucosa in the area, deepen the vestibule, and prevent muscle reinsertion. (Int J Periodontics Restorative Dent 2008;28:617-623.)

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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It is well known that a predator has the potential to regulate a prey population only if the predator responds to increases in prey density and inflicts greater mortality rates. Predators may cause such density-dependent mortality depending on the nature of the functional and numerical responses. As spiders are usually faced with a shortage of prey, the killing behavior of the spider Nesticodes rufipes at varying densities of Musca domestica was examined here through laboratory functional response experiments where spiders were deprived of food for 5 (well-fed) or 20 days (hungry). An additional laboratory experiment was also carried out to assess handling time of spiders. The number of prey killed by spiders over 24- and 168-h periods of predator-prey interaction was recorded. Logistic regression analyses revealed the type II functional response for both well-fed and hungry spiders. We found that the lower predation of hungry spiders during the first hours of experimentation was offset later by an increase in predation ( explained by estimated handling times), resulting in similarity of functional response curves for well-fed and hungry spiders. It was also observed that the higher number of prey killed by well-fed spiders over a 24- h period of spider-prey interaction probably occurred due to their greater weights than hungry spiders. We concluded that hungry spiders may be more voracious than well-fed spiders only over longer time periods, since hungry spiders may spend more time handling their first prey items than well-fed spiders.

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Pearl glands are scattered throughout the lamina of developing leaves and rarely found on adult leaves of Piper regnellii (Piperaceae). The pearl gland is a bicellular secretory trichome composed of a short broad basal cell and a spatula-like, semiglobular apical cell. Four different stages of the pearl grand were determined during its ontogenesis: origin, pre-secretory, secretory and post-secretory. During the pre-secretory stage, mitochondria, ribosomes, dictyosomes, rough endoplasmic reticulum, and plastids with electron dense inclusions were present in the cytoplasm of the apical cell. During the secretory stage, the most remarkable characteristics of the apical cell are the proliferation of dictyosomes and their vesicles, rough endoplasmic reticulum, and modified plastids. At this stage, electron-dense oil drops occur in the plastids as well as scattered within the cytoplasm, proteins and polysaccharides are seen in the plastids, vesicles, and vacuoles. Only polysaccharides are present in the periplasmic space, wall cavities, and on the surface of the apical cell. The polysaccharides are one of the main components of the mucilagenous exudate that covers the developing leaf structures. The apical cell of the senescing trichomes undergoes a progressive degeneration of its cellular components, the plastids being the first organelles to undergo lysis.

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The present study was designed to investigate the effects of a single dose of an estrogen antagonist-clomiphene-during neonatal life, on later neuroendocrine system and reproductive performance. Immediately after birth, male pups received clomiphene citrate (s.c.). At adulthood, although testosterone levels and wet weights of reproductive organs were not altered, the treatment induced an increased number of spermatozoa and a delay in the transit time in the cauda epididymis. Additionally, there was impairment of sexual behavior evidenced by a delay in the latencies to the first mount and first intromission. Treated rats also showed decreased dopaminergic and serotonergic neurotransmissions in the hypothalamus and decreased dopaminergic neurotransmission in the striatum. The decreased dopaminergic activity could be related to the lower sexual motivation observed. These results indicate the necessity of preventing exposure to drugs that may impair sexual differentiation, which can compromise later mating success as well as the capacity to generate descendants. (c) 2006 Elsevier B.V. All rights reserved.

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Hypoxanthine-guanine phosphoribosyltransferase (HGPRTase) is an essential gene of the parasite Schistosoma mansoni and it is well conserved in its hosts (mouse and human) at the protein but not at the RNA level. This feature prompted us to assess RNA interference (RNAi) to combat schistosomiasis. Small interfering RNAs (siRNAs) were Produced against HGPRTase, injected in infected mice and the number of worms was counted six days after injection. The total number of parasites was reduced by approximately 27% after treatment. RT-PCR analyzes showed a significant reduction in parasite target mRNA but not in host's homologue. The use of low doses of molecules did not oversaturate si- or miRNA pathways as mice survival rates were not affected by siRNAs. This is the first successful in vivo demonstration of a RNAi-based treatment against schistosomiasis. We believe that improvements in molecule delivery and an increase on siRNA dose could rapidly eliminate parasite. (c) 2007 Elsevier B.V. All rights reserved.

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Seventy specimens of Hypsiboas albopunctatus (Anura: Hylidae) were collected and surveyed for endoparasites in Brasilia, Brazil at the end of the rainy season (February and March) in 2005. Sixteen males (22.86%) were infected by Rhabdias sp., Aplectana sp., Cosmocerca sp., and Falcaustra mascula. Rhabdias sp., a lung parasite, presented the highest prevalence (8.57%), mean intensity of infestation (1.333), and mean abundance (0.114). Moreover, this is the first report of a rhabdiasid nematode in the Hylidae in Brazil. The intestinal parasites, Cosmocerca sp. and Aplectana sp., had a similar prevalence (5.71%), but the former presented a higher mean intensity of infestation and mean abundance. The behavior and food habits of amphibians are responsible for the differences in their helminthofauna, and this study presents four new records of nematodes in H. albopunctatus.

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

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

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

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In this work, GdAlO3:RE3+ (RE = Eu or Tb) was successfully prepared by the Pechini method at lower temperatures when compared to others methods as solid-state synthesis and sol-gel process. In accordance to the XRD data, the fully crystalline single-phase GdAlO3 could be obtained at 900 degrees C. The differential thermal analysis (DTA) shows a crystallization peak at 850 degrees C. The samples are composed by monocrystalline particles (50-120 nm) exhibiting the formation of aggregates among them, which indicates the beginning of the sinterization process. This feature indicates a strong tendency to the formation of aggregates, which is a suitable ability for the close-packing of particles, and hence a potential application in X-ray intensifying screens. Luminescence measurements indicate Gd3+ -> RE3+ energy transfer. The Eu3+ emission spectra exhibit all the characteristics D-5(0) -> F-7(j) transitions and the observed profile suggests that RE3+ ions occupy at least one site without center of symmetry. For terbium-doped samples, the D-5(3) -> F-7(j) (blue emission) and D-5(4) -> F-7(j) (green emission) transitions were observed and the ratio between them may depend on the Tb3+ content due to cross-relaxation processes. (C) 2009 Elsevier B.V. All rights reserved.

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

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O trabalho teve como objetivo estudar a influência de diferentes densidades populacionais de craveiros, cultivados em casa de vegetação sobre a qualidade das flores. As densidades de plantio estudadas foram de 233.333, 175.000 e 116.667 plantas por hectare, obtidas da utilização dos seguintes espaçamentos: 0,15 m x 0,20 m; 0,20 mx 0,20m e 0,30 m x 0,30 m. Scania Red foi o cultivar utilizado. Os parâmetros analisados foram o número de cravos com cálice inteiro e rachado por planta e por hectare, bem como comprimento da haste com flor, peso da haste com flor e diâmetro da corola. Concluiu-se que o aumento da densidade de plantio ocasionou um acréscimo na produção de cravos com cálice inteiro por hectare, uma diminuição da produção de cravos com cálice rachado por planta, uma diminuição do peso da haste com flor e uma diminuição do diâmetro da corola. Não houve influência da densidade de plantio sobre a produção de cravos com cálice inteiro por planta, sobre a produção de cravos com cálice rachado por hectare e sobre o comprimento da haste com flor.

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The conductivity of poly(p-phenylene sulfide) (PPS) amorphous samples sandwiched between metallic electrodes has been studied as a function of applied voltage, temperature, and electrode material. The voltage (U) dependence of the currents for electric fields within the range 10(3)-10(6) V/cm exhibits exp beta U-1/2 behavior with beta = beta(Schottky) below the glass transition temperature (T-g congruent to 90 degrees C), and beta = beta(Poole-Frenkel) above T-g. Coordinated temperature measurements of de currents with different metallic contacts and thermally stimulated currents (TSC) indicate, however, that the conductivity at T < T-g is consistent with the so-called ''anomalous'' Poole-Frenkel effect rather than the Schottky effect. Consequently, the p-type conductivity in amorphous PPS is proposed to be a bulk-limited process due to ionization of two different types of acceptor centers in the presence of neutral hole traps. (C) 1996 John Wiley & Sons, Inc.

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We have carried out dielectric and Raman spectroscopy studies at the 298-623 K temperature range in polycrystalline Pb0.70Sr0.30TiO3 thin films grown by a soft chemical method. The diffuse phase-transition behavior of the thin films was observed by means of the dielectric constant versus temperature curves, which show a broad peak. Such behavior was confirmed later by Raman spectroscopy measurements up to 823 K, indicating that a diffuselike phase transition takes place at around 548-573 K. The damping factor of the E(1TO) soft mode was calculated using the damped simple harmonic oscillator model. on the other hand, Raman modes persist above the tetragonal to cubic phase transition temperature although all optical modes should be Raman inactive. The origin of these modes was interpreted in terms of a breakdown of the microscopic local cubic symmetry by chemical disorder. The lack of a well-defined transition temperature and the presence of broad bands at some temperature interval above the ferroelectric-paraelectric phase-transition temperature suggested a diffuse nature of the phase transition. This result corroborates the dielectric constant versus temperature data, which showed a broad ferroelectric phase transition in this thin film. (C) 2004 American Institute of Physics.