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Periodic hybrid-exchange density functional theory calculations are used to explore the first layer of water at model oxide surfaces, which is an important step for understanding the photocatalytic reactions involved in solar water splitting. By comparing the structure and properties of SnO2(110) and TiO2(110) surfaces in contact with water, the effects of structural and electronic differences on the water chemistry are examined. The dissociative adsorption mode at low coverage (1/7 ML) up to monolayer coverage (1 ML) on both SnO2 and TiO2(110) surfaces is analysed. To investigate further the intermolecular interactions between adjacent adsorbates, monolayer adsorption on each surface is explored in terms of binding energies and bond lengths. Analysis of the water adsorption geometry and energetics shows that the relative stability of water adsorption on SnO2(110) is governed largely by the strength of the chemisorption and hydrogen bonds at the surface of the adsorbate-substrate system. However on TiO2(110), a more complicated scenario of the first layer of water on its surface arises in which there is an interplay between chemisorption, hydrogen bonding and adsorbate-induced atomic displacements in the surface. Furthermore the projected density of states of each surface in contact with a mixture of adsorbed water molecules and adsorbed hydroxyls is presented and sheds some light on the nature of the crystalline chemical bonds as well as on why adsorbed water has often been reported to be unstable on rutile SnO2(110).

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O presente trabalho teve por objetivo investigar a atividade antioxidante dos extratos das folhas de Cordia verbenacea obtido por maceração em etanol e partição em solventes orgânicos. O infuso das folhas também foi investigado. O teor de fenóis totais foi avaliado pelo método de Folin-Ciocalteau e o de flavonoides totais pela formação de complexo com cloreto de alumínio. O extrato etanólico, as subfrações e o infuso foram testados em diversas concentrações para determinar a atividade sequestradora de DPPH expressa em termos de sua CE50. A melhor atividade antioxidante encontrada foi para o extrato em acetato de etila, EA, CE50 15,0 ± 0,5 µg.mL-1. Os ensaios espectrofotométricos revelaram altas concentrações de fenóis e de flavonoides no extrato EA. A análise por HPLC-DAD foi realizada para se obter o perfil de UV-Vis dos picos cromatográficos do extrato EA. As características espectrais foram relacionadas a compostos fenólicos e flavonoídicos.

The objective of the present study was to investigate the antioxidant activity of extracts from Cordia verbenacea leaves obtained by maceration in ethanol and partitioned with organic solvents. The infusion of leaves was also investigated. The total phenolic and total flavonoid content was evaluated by the Folin-Ciocalteau method and by the aluminum chloride complex method, respectively. The ethanol extract, the subfractions and the infusion were assayed at various concentrations to determine the DPPH scavenging activity expressed in terms of CE50. The best antioxidant activity was found on the ethyl acetate extract, EA, CE50 15.0 ± 0.5 µg.mL-1. The spectrophotometric assays revealed high phenol and flavonoid concentrations on the EA extract. The HPLC-DAD analysis was performed to reveal the UV-Vis profile of the chromatographic peaks of the EA extract. The UV spectral characteristics were related to phenol and polyphenol compounds.

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Thin heteroepitaxial overlayers have been proposed as templates to generate stable, self-organized nanostructures at large length scales, with a variety of important technological applications. However, modeling strain-driven self-organization is a formidable challenge due to different length scales involved. In this Letter, we present a method for predicting the patterning of ultrathin films on micron length scales with atomic resolution. We make quantitative predictions for the type of superstructures (stripes, honeycomb, triangular) and length scale of pattern formation of two metal-metal systems, Cu on Ru(0001) and Cu on Pd(111). Our findings are in excellent agreement with previous experiments and call for future experimental investigations of such systems.

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AIMS: To compare the sensitivity and specificity of new rabbit monoclonal antibody SP3 with those of mouse monoclonal and rabbit polyclonal antibodies using HER2 amplification defined by chromogenic in situ hybridisation (CISH) as the gold standard. METHODS: Serial sections from tissue microarrays (TMAs) containing 84 breast carcinomas were submitted to CISH (Zymed HER2 Spot-Light kit) and immunohistochemistry, using NeoMarkers SP3 (rabbit monoclonal), DAKO A0485 and DAKO HercepTest (polyclonal), Novocastra NCL-CB11, Cell Marque CM-CB11, and Genentech 4D5 (mouse monoclonal). RESULTS: The best antibody concordance was between SP3 and HercepTest (kappa = 0.74). SP3, A0485 and HercepTest detected all HER2 amplified tumours, but were less specific than mouse monoclonal antibodies. 3/38 (7.9%) and 8/38 (21.0%) non-amplified tumours were scored as 3+ using SP3 and A0485, respectively. 3/46 (6.5%) amplified tumours were negative for NCL-CB11. SP3, HercepTest and A0485 showed no gene amplification on 55%, 62.5% and 92.3% of the 2+ scored tumours, but most of the 2+ scored tumours using monoclonal antibodies were amplified by CISH (80-92.3%). CONCLUSIONS: SP3 is more sensitive than mouse monoclonal antibodies for Her2 assessment. However, HercepTest, CB11 and 4D5 show higher specificity than SP3 for the identification of HER2 gene amplification. Mouse monoclonal antibodies show less Her2 2+ tumours; most are amplified by CISH.

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Water used in hydrotherapy units of Nova Iguaçu and Nilópolis, Rio de Janeiro State, Brazil, was microbiologically analyzed. Thirty samples (5ml each) were weekly collected from September 2001 to June 2002 before the beginning and after the end of activities in the units. For analysis, routine techniques were used, which showed the presence of Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, Klebsiella spp, Candida spp, Penicillium spp, Epidermophyton spp, Aspergillus fumigatus, Aspergillus niger, Aspergillus spp, Cephalosporium spp, Cladosporium spp, Trichophyton rubrum, and Trichophyton spp. Results indicated a need for improving hygienic conditions, suggesting that water might be a contamination source in the evaluated units

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A survey was carried out in a hospital of Nova Iguaçu, Rio de Janeiro, Brazil, in the period from July 1999 to March 2002, to determine the infection rate of Listeriamonocytogenes in HIV+ patients with diarrhea symptoms; 134 samples were processed by microbiological methods. The results demonstrated 12.68% of positive samples. However, no statistical differences were observed for age or sex in the studied group, suggesting that this microorganism should be regarded in the differential diagnosis of infectious processes in HIV+ patients in the area.

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A survey was carried out in a hospital of Nova Iguaçu, Rio de Janeiro, Brazil, in the period from July 1999 to March 2002, to determine the infection rate of Listeria monocytogenes in HIV+ patients with diarrhea symptoms; 134 samples were processed by microbiological methods. The results demonstrated 12.68% of positive samples. However, no statistical differences were observed for age or sex in the studied group, suggesting that this microorganism should be regarded in the differential diagnosis of infectious processes in HIV+ patients in the area

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The frequency of envenoming in Northwest counties of the Rio de Janeiro State, Brazil, from 1995 to 2000 was evaluated. Reports from the Municipal Secretariat of Health of these counties were used. The results demonstrated that, from 1997 to 1999, there was a shortage of notification, and 40 cases of envenomations caused by Bothrops snakes were registered. These cases were more common from February to October, and the lower limbs of male peasants were the mainly affected areas.(AU)

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The principle advantages of open rhinoplasty concern diagnosis as well as technical facilities. The transcolumelar approach, initially described by Rheti in 1934 for surgical corrections of the cleft lip nose, was adopted by us since 1992 in 48 patients. We have systematically made a "staggered incision" at the collumella's narrowest point, that allows a great view of nasal structures. The results were considered good, even in difficult rhinoplasties. The scars were inconspicous, without cicatricial hypertrophies or deformities.

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