887 resultados para 3.5G EUL Techniques


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This review summarizes the chromosomal changes detected by molecular cytogenetic approaches in esophageal squamous cell carcinoma (ESCC), the ninth most common malignancy in the world. Whole genome analyses of ESCC cell lines and tumors indicated that the most frequent genomic gains occurred at 1, 2q, 3q, 5p, 6p, 7, 8q, 9q, 11q, 12p, 14q, 15q, 16, 17, 18p, 19q, 20q, 22q and X, with focal amplifications at 1q32, 2p16-22, 3q25-28, 5p13-15.3, 7p12-22, 7q21-22, 8q23-24.2, 9q34, 10q21, 11p11.2, 11q13, 13q32, 14q13-14, 14q21, 14q31-32, 15q22-26, 17p11.2, 18p11.2-11.3 and 20p11.2. Recurrent losses involved 3p, 4, 5q, 6q, 7q, 8p, 9, 10p, 12p, 13, 14p, 15p, 18, 19p, 20, 22, Xp and Y. Gains at 5p and 7q, and deletions at 4p, 9p, and 11q were significant prognostic factors for patients with ESCC. Gains at 6p and 20p, and losses at 10p and 10q were the most significant imbalances, both in primary carcinoma and in metastases, which suggested that these regions may harbor oncogenes and tumor suppressor genes. Gains at 12p and losses at 3p may be associated with poor relapse-free survival. The clinical applicability of these changes as markers for the diagnosis and prognosis of ESCC, or as molecular targets for personalized therapy should be evaluated.

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Among the osteotomies performed in orthognathic surgery, the sagittal osteotomy of the mandibular ramus (SOMR) is the most common, allowing a great range of movements and stable internal fixation (SIF), therefore eliminating the need of maxillomandibular block in the postoperative period. Objectives: The purpose of this study was to evaluate the biomechanical resistance of three national systems used for SIF in SOMR in sheep mandibles. Material and methods: The study was performed in 30 sheep hemi-mandibles randomly divided into 3 experimental groups, each containing 10 hemi-mandibles. The samples were measured to avoid discrepancies and then subjected to SOMR with 5-mm advancement. In group I, 2.0x12 mm screws were used for fixation, inserted in an inverted "L" pattern (inverted "L" group). In group II, fixation was performed with two 2.0x12 mm screws, positioned in a linear pattern and a 4-hole straight miniplate and four 2.0x6.0 mm monocortical screws (hybrid group). In group III, fixation was performed with two-hole straight miniplates and eight 2.0x6.0 mm monocortical screws (mini plate group). All materials used for SIF were supplied by Osteosin - SIN. The hemimandibles were subjected to vertical linear load test by Kratos K2000MP mechanical testing unit for loading registration and displacement. Results: All groups showed similar resistance during mechanical test for loading and displacement, with no statistically significant differences between groups according to analysis of variance. Conclusion: These results indicate that the three techniques of fixation are equally effective for clinical fixation of SOMR.

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

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Objectives: To evaluate the influence of different protocols for resin cement removal during cementation on biofilm formation.Methods: Twenty-eight ceramic blocks, which were injected under pressure, were placed over enamel blocks obtained from freshly extracted bovine incisors. The ceramic blocks were cemented to the enamel blocks using a dual-cured resin cement and the excess resin was removed according to the experimental group: TS: Teflon spatula; BR: brush; BR+: brush and polishing; SB+: scalpel blade and polishing. After autoclaving, the samples were colonised by incubation in a sucrose broth suspension standardised with Streptococcus mutans in microaerophilic stove. Specimens were quantitatively analysed for bacterial adherence at the adhesive interface using confocal laser scanning microscopy and counting the colony forming units, and qualitatively analysed using SEM. The roughness (Ra/Rz/RSm) was also analysed. Data were analysed by 1-way ANOVA and Tukey's test (5%).Results: The roughness values ranged from 0.96 to 1.69 mu m for Ra (p > 0.05), from 11.59 to 22.80 mu m for Rz (p = 0.02 < 0.05) and from 293.2 to 534.3 mu m for RSm (p = 0.00). Bacterial adhesion varied between 1,974,000 and 2,814,000 CFU/ml (p = 0.00). Biofilm mean thickness ranged from 0.477 and 0.556 mu m (p > 0.05), whilst the biovolume values were between 0.388 and 0.547 mu m(3)/mu m(2) (p = 0.04). Lower values for roughness, bacterial adhesion, biofilm thickness and biovolume were found with BR, whilst TS presented the highest values for most of the parameters. SEM images confirmed the quantitative values.Conclusions: The restoration margin morphology and interface roughness affects bacterial accumulation. The brush technique promoted less bacterial colonisation at the adhesive interface than did the other removal methods.Clinical significance: The brush technique seems to be a good option for removing the excess resin cement after adhesive cementation in clinical practice, as indicated by its better results with lower bacterial colonisation. (C) 2012 Elsevier Ltd. All rights reserved.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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This paper considers the dynamics of two planets, as the planets B and C of the pulsar PSR B1257+12, near a 3/2 mean-motion resonance. A two-degrees-of-freedom model, in the framework of the general three-body planar problem, is used and the solutions are analyzed through surfaces of section and Fourier techniques in the full phase space of the system.

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Four types of stainless steel coatings prepared by a high velocity oxy-fuel spraying system (HVOF) were studied. Differences among coated steels were related to the spraying parameters, which influenced the behavior of the samples against the corrosion. The electrochemical behavior of the stainless steel coatings was strongly influenced by porosity, the presence of micro- and macro-cracks, and also of un-melted particles. Once the electrolyte reached the steel substrate via these defects, the galvanic pair formed between the coating and substrate-accelerated corrosion, leading to the depletion of the coating. (C) 2004 Elsevier Ltd. All rights reserved.

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The speciose Brazilian Elateridae fauna is characterized by high karyotypic diversity, including one species (Chalcolepidius zonatus Eschscholtz, 1829) with the lowest diploid number within any Coleoptera order. Cytogenetic analysis of Conoderus dimidiatus Germar, 1839, C. scalaris (Germar, 1824,) C. ternarius Germar, 1839, and C. stigmosus Germar, 1839 by standard and differential staining was performed with the aim of establishing mechanisms of karyotypic differentiation in these species. Conoderus dimidiatus, C. scalaris, and C. ternarius have diploid numbers of 2n(male) = 17 and 2n(female) = 18, and a X0/XX sex determination system, similar to that encountered in the majority of Conoderini species. The karyotype of C. stigmosus was characterized by a diploid number of 2n=16 and a neoXY/neoXX sex determination system that was highly differentiated from other species of the genus. Some features of the mitotic and meiotic chromosomes suggest an autosome/ancestral X chromosome fusion as the cause of the neoXY system origin in C. stigmosus. C-banding and silver impregnation techniques showed that the four Conoderus species possess similar chromosomal characteristics to those registered in most Polyphaga species, including pericentromeric C band and autosomal NORs. Triple staining techniques including CMA(3)/DA/DAPI also provided useful information for differentiating these Conoderus species. These techniques revealed unique GC-rich heterochromatin associated with NORs in C. scalaris and C. stigmosus and CMA(3)-heteromorphism in C. scalaris and C. ternarius.

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This paper investigates properties of integer programming models for a class of production planning problems. The models are developed within a decision support system to advise a sales team of the products on which to focus their efforts in gaining new orders in the short term. The products generally require processing on several manufacturing cells and involve precedence relationships. The cells are already (partially) committed with products for stock and to satisfy existing orders and therefore only the residual capacities of each cell in each time period of the planning horizon are considered. The determination of production recommendations to the sales team that make use of residual capacities is a nontrivial optimization problem. Solving such models is computationally demanding and techniques for speeding up solution times are highly desirable. An integer programming model is developed and various preprocessing techniques are investigated and evaluated. In addition, a number of cutting plane approaches have been applied. The performance of these approaches which are both general and application specific is examined.

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Ultrafine PbZr0.20Ti0.80O3 was omorphized through high-energy mechanical milling. The structural evolution through the omorphization process was accompanied by various characterization techniques, such as X-ray diffraction, Fourier-transformed IR spectroscopy (FTIR), high-resolution transmission electron microscopy (HR-TEM), and Raman spectroscopy. A strong photoluminescence was measured at room temperature for amorphized PbZr0.20Ti0.80O3, and interpreted by means of high-level quantum mechanical calculations in the density functional theory frame-work. Three periodic models were used to represent the crystalline and amorphized PbZr0.20Ti0.80O3, and they allowed the calculation of electronic properties that are consistent with the experimental data and that explain the appearance of photoluminescence.

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Silica gel, chemically modified with 2,5-dimercapto-1,3,4-thiadiazole [=Si(CH2)(3)-NC2HNS3], abbreviated as SiB, was used to adsorb metal ions from ethanol by both batch and column techniques. Elution of Cu(II) was done with a solvent mixture of acetone and hydrochloric acid (9:1 v/v). Zn(II), Cd(II), Ni(II), Pb(II), Co(II) and Fe(III) were eluted with 0.5 mol l(-1) HC1 in ethanol solution. The modified silica was applied in the preconcentration of metal ions from commercial ethanol, normally used as engine fuel. The method is suitable for quantifying these metals at low mu g l(-1) levels.

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An amperometric biosensor based on cholinesterase (ChE) has been used for the determination of selected carbamate insecticides in vegetable samples. The linear range of the biosensor for the N-methylcarbamates (aldicarb, carbaryl, carbofuran, methomyl and propoxur) varied from 5 x 10(-5) to 50 mg kg(-1). Limits of detection were calculated on the basis that the ChE enzymes were 10% inhibited and varied, depending of the combination ChE (as acetyl- or butyrylcholinesterase) vs. inhibitor (pesticide), from 1 x 10(-4) to 3.5 mg kg(-1). The biosensor-based carbamate determination was compared to liquid chromatography/UV methods. Three vegetable samples were spiked with carbofuran and propoxur at 125 mu g kg(-1) followed by conventional procedures. Good correlations were observed for carbofuran in the vegetable extracts (79, 96 and 91% recoveries for potato, carrot and sweet pepper, respectively), whereas for propoxur unsatisfactory results were obtained. Potato and carrot samples were spiked with 10, 50 and 125 mu g kg(-1) carbofuran, followed by direct determination by the amperometric biosensor. The fortified sampler; resulted in very high inhibition values, and recoveries were: 28, 34 and 99% for potato, and 140, 90 and 101% for carrot, respectively, at these three fortification levels. (C) 1998 Elsevier B.V. B.V.

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Statement of problem. Cavity and tooth preparations generate heat because the use of rotary cutting instruments on dental tissues creates friction. Dental pulps cannot survive temperature increases greater than 5.5degreesC.Purpose. This study evaluated the efficiency of 3 different water flows for 2 different tooth preparation techniques to determine which are safe for use.Material and methods. Thermocouples were placed in the pulpal chambers of 30 bovine teeth, and 1 of 2 tooth preparation techniques was used: a low-load intermittent tooth preparation technique or a high-load tooth preparation technique without intervals. Water flows of 0, 30, and 45 mL/min were associated with each technique, for a total of 6 different groups. The results were analyzed with a 2-factor analysis of variance (P<.05).Results. Temperature increases with the high-load technique were 16.40&DEG;C without cooling (group 1), 11.68&DEG;C with 30 mL/min air-water spray cooling (group III), and 9.96&DEG;C with 45 mL/min cooling (group V). With the low-load tooth preparation technique, a 9.54&DEG;C increase resulted with no cooling (group II), a 1.56&DEG;C increase with 30 mL/min air-water spray cooling (group TV), and a 0.04&DEG;C decrease with 45 mL/min cooling (group VI). The low-load technique was associated with more ideal temperature changes.Conclusion. The results of this study confirm the necessity of using a low-load technique and water coolants during cavity and tooth preparation procedures.

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PTCR barium titanate has been prepared following two different powder preparation techniques: the solid-state reaction route and co-precipitation route for the comparison of results. The co-precipitation route produces better PTCR characteristics with low room temperature resistivity and better reproducibility of prepared samples. The effects of different concentrations of additives like donors, acceptors and excess titanium have been optimized to get good quality PTCR samples. (C) 2002 Elsevier B.V. B.V. All rights reserved.