877 resultados para Lucy Skaer


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Purpose: The aim of this study was to evaluate the accuracy of cone-beam computed tomography (CBCT) for measuring the buccal bone volume around dental implants. Materials and methods: Three to six implants were inserted into the anterior maxilla of eight skulls, depending on the availability of bone, and after this, the CBCT was performed. By means of CBCT image, measurements of the bone wall at three points of the implant were obtained, analyzed and compared with those obtained in the plaster skull casting. Results: The results showed that for the three points of the implants, no statistically significant difference in the measurements was obtained from the plaster model and CBCT images. Conclusions: CBCT can be a useful tool for assessing buccal bone volume along the implant. To cite this article:?Shiratori LN, Marotti J, Yamanouchi J, Chilvarquer I, Contin I, Tortamano-Neto P. Measurement of buccal bone volume of dental implants by means of cone-beam computed tomography.?Clin. Oral Impl. Res. 23, 2012; 797804.?doi: 10.1111/j.1600-0501.2011.02207.x

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The hydroponic cultivation of vegetables has increased markedly in recent years, however, little is known about its chemical composition, which is of extreme importance in view of changing food habits of a considerable fraction of the population seeking food quality. For this reason, cultivation of watercress, chicory, rocket and lettuce American (Lucy Brown) and smooth (cv. Regina) were grown in hydroponics, NFT system, aiming to evaluate the yield, nitrate content and chemical composition. The experiment was conducted in a greenhouse at the Universidade Federal de Santa Catarina, Florianopolis city in the Santa Catarina State (Brazil), from may to july 2004 under a completely randomized design with four replications. The spacing used was 25 x 25 cm for the crops of watercress, chicory and lettuce (cv. Lucy Brown and cv. Regina) and 5 x 5 cm to the rocket. The traits were: number of leaves, nitrate content and chemical composition of vegetables. The lettuce cv. Regina and chicory had higher number of leaves per plant. The watercress had lower water content and higher dry mass of shoots. The largest increase in fresh weight was obtained in chicory, lettuce, cv. Regina. Higher levels of lipids, protein, ash, carbohydrates, calories, fiber and nitrate were obtained from the watercress. The rocket had lower values for the variables fresh and dries the whole plant, shoot and root and leaf number per plant. All cultures showed good visual appearance, low calorie and nitrate levels suitable for human consumption.

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Osteoporotic hip fractures (OHF) are not limited to elderly; however, studies in non-elderly are scarce. Thus, the aim of this study was to evaluate co-morbidities in non-elderly patients with OHF in a Community Teaching Hospital. All hospitalizations due to OHF during a 3-year period in a Community Teaching Hospital were retrospectively evaluated for co-morbidities, and patients 18-64 years old were compared with those a parts per thousand yen65 years old. Of all hospitalizations, 232 (0.73%) were due to hip fractures, and 120/232 (51.7%) patients had OHF. The comparison of the 13 (10.8%) OHF patients < 65 years old (47.3 +/- A 9.7 years) with 107 (89.2%) a parts per thousand yen65 years old (80.4 +/- A 7.7 years) revealed a male predominance (61.5 vs. 27.1%, P = 0.022) and a distinct ethnic distribution with a lower proportion of Caucasians in the former (61.5 vs. 86.9%, P = 0.033). Moreover, non-elderly OHF patients had higher frequencies of insulin-dependent DM (38.5 vs. 3.7%, P = 0.001) and alcoholism (38.5 vs. 4.7%, P = 0.001) than aged patients. In contrast, rates of age-related co-morbidities such as stroke (7.7 vs. 18.7%, P = 0.461), heart failure (23.1 vs. 14.0%, P = 0.411), and dementia (7.7 vs. 15.9%, P = 0.689) were comparable in both groups. Logistic regression analysis demonstrated that insulin-dependent DM (OR = 25.4, 95% CI = 4.7-136.8, P < 0.001) and alcoholism (OR = 20.3, 95% CI = 3.9-103.3, P < 0.001) remained as independent risk factors for OHF in non-elderly patients. Osteoporosis is an important cause of HF in Community Hospital. Non-elderly patients with OHF have a peculiar demographic profile and associated co-morbidities. These findings reinforce the need of early osteoporosis diagnosis and rigorous fracture prevention in patients with DM and alcoholism.

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We performed an ab initio investigation on the properties of rutile tin oxide (SnOx) nanowires. We computed the wire properties determining the equilibrium geometries, binding energies, and electronic band structures for several wire dimensions and surface facet configurations. The results allowed us to establish scaling laws for the structural properties, in terms of the nanowire perimeters. The results also showed that the surface states control most of the electronic properties of the nanowires. Oxygen incorporation in the nanowire surfaces passivated the surface-related electronic states, and the resulting quantum properties and scaling laws were fully consistent with electrons confined inside the nanowire. Additionally, oxygen incorporation in the wire surfaces generated an unbalanced concentration of spin up and down electrons, leading to magnetic states for the nanowires.

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By combining first-principles electronic structure calculations and existing time-differential gamma-gamma perturbed-angular-correlation experiments we studied the site localization, the local environment, and the electronic structure of Cd impurities in sapphire (alpha-Al2O3) single crystals in different charged states. The ab initio calculations were performed with the full-potential augmented plane wave plus local orbitals method and the projector augmented wave method. Comparing the calculated electric-field-gradient tensor at the Cd nuclei in the alpha-Al2O3 host lattice and the corresponding available experimental values, we have seen that it is equally possible for Cd to replace an Al atom (in a negative charge state) or to be placed in an interstitial site (in a neutral charge state). To finally address the issue of the Cd impurity localization, we performed formation energy calculations. These results have shown that Cd placed in the substitutional Al site, in the negatively charged state, is the most probable configuration.

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Chronic kidney diseasemineral bone disorder (CKD-MBD) is defined by abnormalities in mineral and hormone metabolism, bone histomorphometric changes, and/or the presence of soft-tissue calcification. Emerging evidence suggests that features of CKD-MBD may occur early in disease progression and are associated with changes in osteocyte function. To identify early changes in bone, we utilized the jck mouse, a genetic model of polycystic kidney disease that exhibits progressive renal disease. At 6 weeks of age, jck mice have normal renal function and no evidence of bone disease but exhibit continual decline in renal function and death by 20 weeks of age, when approximately 40% to 60% of them have vascular calcification. Temporal changes in serum parameters were identified in jck relative to wild-type mice from 6 through 18 weeks of age and were subsequently shown to largely mirror serum changes commonly associated with clinical CKD-MBD. Bone histomorphometry revealed progressive changes associated with increased osteoclast activity and elevated bone formation relative to wild-type mice. To capture the early molecular and cellular events in the progression of CKD-MBD we examined cell-specific pathways associated with bone remodeling at the protein and/or gene expression level. Importantly, a steady increase in the number of cells expressing phosphor-Ser33/37-beta-catenin was observed both in mouse and human bones. Overall repression of Wnt/beta-catenin signaling within osteocytes occurred in conjunction with increased expression of Wnt antagonists (SOST and sFRP4) and genes associated with osteoclast activity, including receptor activator of NF-?B ligand (RANKL). The resulting increase in the RANKL/osteoprotegerin (OPG) ratio correlated with increased osteoclast activity. In late-stage disease, an apparent repression of genes associated with osteoblast function was observed. These data confirm that jck mice develop progressive biochemical changes in CKD-MBD and suggest that repression of the Wnt/beta-catenin pathway is involved in the pathogenesis of renal osteodystrophy. (C) 2012 American Society for Bone and Mineral Research.

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Large areas of Amazonian evergreen forest experience seasonal droughts extending for three or more months, yet show maximum rates of photosynthesis and evapotranspiration during dry intervals. This apparent resilience is belied by disproportionate mortality of the large trees in manipulations that reduce wet season rainfall, occurring after 2-3 years of treatment. The goal of this study is to characterize the mechanisms that produce these contrasting ecosystem responses. A mechanistic model is developed based on the ecohydrological framework of TIN (Triangulated Irregular Network)-based Real Time Integrated Basin Simulator + Vegetation Generator for Interactive Evolution (tRIBS+VEGGIE). The model is used to test the roles of deep roots and soil capillary flux to provide water to the forest during the dry season. Also examined is the importance of "root niche separation," in which roots of overstory trees extend to depth, where during the dry season they use water stored from wet season precipitation, while roots of understory trees are concentrated in shallow layers that access dry season precipitation directly. Observational data from the Tapajo's National Forest, Brazil, were used as meteorological forcing and provided comprehensive observational constraints on the model. Results strongly suggest that deep roots with root niche separation adaptations explain both the observed resilience during seasonal drought and the vulnerability of canopy-dominant trees to extended deficits of wet season rainfall. These mechanisms appear to provide an adaptive strategy that enhances productivity of the largest trees in the face of their disproportionate heat loads and water demand in the dry season. A sensitivity analysis exploring how wet season rainfall affects the stability of the rainforest system is presented. Citation: Ivanov, V. Y., L. R. Hutyra, S. C. Wofsy, J. W. Munger, S. R. Saleska, R. C. de Oliveira Jr., and P. B. de Camargo (2012), Root niche separation can explain avoidance of seasonal drought stress and vulnerability of overstory trees to extended drought in a mature Amazonian forest, Water Resour. Res., 48, W12507, doi:10.1029/2012WR011972.

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We investigated the clinical impact of human coronaviruses (HCoV) OC43, 229E, HKU1 and NL63 in pediatric patients with cystic fibrosis (CF) during routine and exacerbation visits. A total of 408 nasopharyngeal aspirate samples were obtained from 103 patients over a 1-year period. Samples positive for HCoV were submitted for nucleotide sequencing to determine the species. Nineteen samples (4.65%) were positive for HCoV, of which 8 were positive for NL63, 6 for OC43, 4 for HKU1, and 1 for 229E. Identification of HCoV was not associated with an increased rate of respiratory exacerbations, but NL63-positive patients had higher exacerbation rates than patients who were positive for other HCoV species.

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Non-mechanised sugarcane harvesting preceded by burning exposes workers and the people of neighbouring towns to high concentrations of pollutants. This study was aimed to evaluate the respiratory symptoms, lung function and oxidative stress markers in sugarcane workers and the residents of Mendonca, an agricultural town in Brazil, during the non-harvesting and harvesting periods and to assess the population and individual exposures to fine particulate matter (PM2.5). Sugarcane workers and healthy volunteers were evaluated with two respiratory symptom questionnaires, spirometry, urinary 1-hydroxypyrene levels, and the measurement of antioxidant enzymes and plasma malonaldehyde during the non-harvesting and harvesting periods. The environmental assessment was determined from PM2.5 concentration. PM2.5 level increased from 8 mu g/m(3) during the non-harvesting period to 23.5 mu g/m(3) in the town and 61 mu g/m(3) on the plantations during the harvesting period. Wheezing, coughing, sneezing, and breathlessness increased significantly in both groups during the harvesting period, but more markedly in workers. A decrease in lung function and antioxidant enzyme activity was observed in both populations during harvesting; this decrease was greater among the sugarcane workers. The urinary 1-hydroxypyrene levels only increased in the sugarcane workers during the harvesting period. The malonaldehyde levels were elevated in both groups, with a higher increase observed in the workers. This research demonstrates the exposure of sugarcane workers and the inhabitants of a neighbouring town to high PM2.5 concentrations during the sugarcane harvest period. This exposure was higher among the sugarcane workers, as illustrated by both higher PM2.5 concentrations in the sugarcane fields and higher urinary 1-hydroxypyrene levels in the volunteers in this group. The higher incidence of respiratory symptoms, greater decrease in lung function and more marked elevation of oxidative stress markers among the sugarcane workers during the harvest confirms the greater effect magnitude in this population and a dose-dependent relationship between pollution and the observed effects. (C) 2012 Elsevier B.V. All rights reserved.

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In 2010, a large outbreak of dengue occurred in Santos, Brazil. The detection of the NS1 antigen was used for diagnosis in addition to the detection of IgG, IgM, and RNA. A large number of NS1 false-negative results were obtained. A total of 379 RNA-positive samples were selected for thorough evaluation. NS1 was reactive in 37.7% of cases. Most of the cases were characterized as a secondary infection by dengue 2 virus. Sequencing of NS1 positive and negative isolates did not reveal any mutation that could justify the diagnostic failure. Use of existing NS1 tests in the Brazilian population may present a low negative predictive value, and they should be used with caution, preferentially after performing a validation with samples freshly obtained during the ongoing epidemic.

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In this article, using first-principles electronic structure calculations within the spin density functional theory, alternated magnetic and non-magnetic layers of rutile-CrO2 and rutile-SnO2 respectively, in a (CrO2) n (SnO2) n superlattice (SL) configuration, with n being the number of monolayers which are considered equal to 1, 2, ..., 10 are studied. A half-metallic behavior is observed for the (CrO2) n (SnO2) n SLs for all values of n. The ground state is found to be FM with a magnetic moment of 2 μB per chromium atom, and this result does not depend on the number of monolayers n. As the FM rutile-CrO2 is unstable at ambient temperature, and known to be stabilized when on top of SnO2, the authors suggest that (CrO2) n (SnO2) n SLs may be applied to spintronic technologies since they provide efficient spin-polarized carriers.

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Abstract Background Bacillus sp. H2O-1, isolated from the connate water of a Brazilian reservoir, produces an antimicrobial substance (denoted as AMS H2O-1) that is active against sulfate reducing bacteria, which are the major bacterial group responsible for biogenic souring and biocorrosion in petroleum reservoirs. Thus, the use of AMS H2O-1 for sulfate reducing bacteria control in the petroleum industry is a promising alternative to chemical biocides. However, prior to the large-scale production of AMS H2O-1 for industrial applications, its chemical structure must be elucidated. This study also analyzed the changes in the wetting properties of different surfaces conditioned with AMS H2O-1 and demonstrated the effect of AMS H2O-1 on sulfate reducing bacteria cells. Results A lipopeptide mixture from AMS H2O-1 was partially purified on a silica gel column and identified via mass spectrometry (ESI-MS). It comprises four major components that range in size from 1007 to 1049 Da. The lipid moiety contains linear and branched β-hydroxy fatty acids that range in length from C13 to C16. The peptide moiety contains seven amino acids identified as Glu-Leu-Leu-Val-Asp-Leu-Leu. Transmission electron microscopy revealed cell membrane alteration of sulfate reducing bacteria after AMS H2O-1 treatment at the minimum inhibitory concentration (5 μg/ml). Cytoplasmic electron dense inclusions were observed in treated cells but not in untreated cells. AMS H2O-1 enhanced the osmosis of sulfate reducing bacteria cells and caused the leakage of the intracellular contents. In addition, contact angle measurements indicated that different surfaces conditioned by AMS H2O-1 were less hydrophobic and more electron-donor than untreated surfaces. Conclusion AMS H2O-1 is a mixture of four surfactin-like homologues, and its biocidal activity and surfactant properties suggest that this compound may be a good candidate for sulfate reducing bacteria control. Thus, it is a potential alternative to the chemical biocides or surface coating agents currently used to prevent SRB growth in petroleum industries.

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Abstract Background The Brazilian Study on the Practice of Diabetes Care main objective was to provide an epidemiological profile of individuals with type 1 and 2 diabetes mellitus (DM) in Brazil, concerning therapy and adherence to international guidelines in the medical practice. Methods This observational, cross-sectional, multicenter study collected and analyzed data from individuals with type 1 and 2 DM attending public or private clinics in Brazil. Each investigator included the first 10 patients with type 2 DM who visited his/her office, and the first 5 patients with type 1 DM. Results A total of 1,358 patients were analyzed; 375 (27.6%) had type 1 and 983 (72.4%) had type 2 DM. Most individuals were women, Caucasian, and private health care users. High prevalence rates of hypertension, dyslipidemia and central obesity were observed, particularly in type 2 DM. Only 7.3% and 5.1% of the individuals with types 1 and 2 DM, respectively, had optimal control of blood pressure, plasma glucose and lipids. The absence of hypertension and female sex were associated with better control of type 1 DM and other cardiovascular risk factors. In type 2 DM, older age was also associated with better control. Conclusions Female sex, older age, and absence of hypertension were associated with better metabolic control. An optimal control of plasma glucose and other cardiovascular risk factors are obtained only in a minority of individuals with diabetes. Local numbers, compared to those from other countries are worse.

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Chemical abrasion was carried out on zircons grains of the Temora II standard for U-Pb dating prior to analyses using in situ Laser Ablation-MultiCollector Ion Coupled Plasma Mass Spectrometer (LA-ICPMS) followed by the Isotope Dissolution Thermal Ionization Mass Spectrometer (ID-TIMS) method. The proposed methodology was herein applied in order to reduce primarily the effects of secondary Pb loss, the presence of common lead and/or silicate impurities. Nine Temora II zircon grains were analyzed by the laser ablation method yielding an age of 418.3±4.3 Ma. Zircon grains of a same population were separated for chemical abrasion before dissolution and mass spectrometry analyses. Six fractions of them were separated for isotope dissolution using 235U-205Pb mixed spike after we have checked and assured the laboratory conditions of low blank values for total Pb of less than 2 pg/g. The obtained U-Pb zircon age by the ID-TIMS method was 415.7±1.8 Ma (error 0.43 %) based on four successful determinations. The results are consistent with the published ages for the Temora diorite (Temora I â 416.75±1.3 Ma; Temora II â 416.78±0.33 Ma) and established as 416±0.33 Ma. The technique is thus recommended for high precision U-Pb zircon analyses (error < 1 %), mainly for high resolution stratigraphic studies of Phanerozoic sequences.

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A Informação Profissional, um dos componentes do processo de Orientação Profissional Vocacional ou para a Carreira, visa fornecer dados da realidade do mundo ocupacional de forma a auxiliar pessoas em processos de tomada de decisão. Este estudo objetiva sistematizar e analisar a produção do conhecimento sobre a temática Informação Profissional com base na revisão da literatura. Os dados foram organizados em três categorias, com base em Robinson e colaboradores: (1) modelos de recursos impressos, (2) programas e sistemas de informação e (3) sites na internet. Os resultados mostram que as novas Tecnologias da Informação e Comunicação (TICs) aliadas às estratégias tradicionais representam inúmeras oportunidades de desenvolvimento da Informação Profissional, com desafios e limites a serem enfrentados em um campo que não para de evoluir. O estudo evidencia o papel da Informação Profissional, com seus limites e possibilidades, no contexto brasileiro bem como nos países desenvolvidos.