897 resultados para structured wall pipe


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The purpose of this study was to evaluate the repair process in the reconstruction of the anterior wall of the frontal sinus of monkeys with bovine bone matrix. Four adult Cebus apella monkeys underwent an ostectomy of the anterior wall of the frontal sinus. The frontal sinus mucosa and the nasofrontal duct were not manipulated. Reconstruction occurred with implants of bovine bone matrix laminae measuring 2.0 x 2.5 cm and 0.4 mm thick, stabilized under pressure in the lateral wall of the frontal sinus. The monkeys were sacrificed over a period of 150 days and routine laboratory procedures were followed for hematoxylin-eosin staining and histologic evaluation of the specimens. Neoformed bone tissue was observed in contact with the frontal sinus mucosa and the bovine bone matrix. The frontal sinus mucosa remained whole without fibrous tissue or cystic formations. There was no occurrence of cellularization as well as revascularization of the bovine bone matrix, though it has permitted bone conduction on this surface. It was possible to conclude that the demineralized bovine bone matrix was biotolerable, being incorporated into the bone without the presence of inflammatory cells with characteristics of inertness and antigenicity and behaved as an osteoconductive material.

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Few studies has been done using guided bone regeneration in maxillary sinus defects. AIM: To assess the bone repair process in surgical defects on the alveolar wall of the monkey maxillary sinus, which communicates with the sinus cavity, by using collagen membranes: Gen-derm - Genius Baumer, Pro-tape - Proline and autologous temporal fascia. MATERIALS AND METHODS: In this prospective and experimental study, orosinusal communications were performed in four tufted capuchin monkeys (Cebus apella) and histologic analysis was carried out 180 days after. RESULTS: In the defects without a cover (control), bone proliferation predominated in two animals and fibrous connective tissue predominated in the other two. In defects repaired with a temporal fascia flap, fibrous connective tissue predominated in three animals and bone proliferation predominated in one. In the defects repaired with Gen-derm or Pro-tape collagen membranes there was complete bone proliferation in three animals and fibrous connective tissue in one. CONCLUSIONS: Surgical defect can be repaired with both bone tissue and fibrous connective tissue in all study groups; collagen membranes was more beneficial in the bone repair process than temporal fascia or absence of a barrier.

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The main purpose of this article is to relate two among the most important themes of the current organizational dynamic: organizational culture, innovation and environmental management. Great part of the literature about environmental management and environmental innovation refers to organizational culture as the most arduous wall or the most significant element to develop effective practices of business environmental management. However, relationship among such concepts is, many times, superficial or camouflaging the necessary analytic depth. To solve this challenge, this article integrates the levels of the organizational culture (workmanships, values and presupposed unconscious), the typologies of environmental innovation (total productivity of resources, innovations for the segregation of materials and articulation of bio-systems), and the environmental technologies (end-of-pipe, environmental measurement, pollution prevention and zero-impact technology). Recommendations and challenges for the continuity of this research are registered.

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O presente trabalho visa a fornecer uma contribuição ao estudo dos perfis formados a frio sob altas temperaturas, em conseqüência da deflagração de um incêndio. Especificamente, abordam–se assuntos inerentes ao fenômeno da transferência de calor em paredes do tipo steel frame – dry wall com ou sem isolamento térmico na cavidade. Para tanto, propõem–se modelos computacionais capazes de fornecer, com certa precisão, o valor de temperatura em qualquer ponto do sistema estudado. Dessa forma, é possível, então, traçar configurações de distribuição de temperatura (uniforme ou não–uniforme) na seção transversal dos montantes que constituem o painel, fornecendo subsídios para análise de estabilidade e pós–flambagem dos elementos estruturais em questão. As simulações numéricas de transferência de calor são efetuadas com auxílio dos programas computacionais ABAQUS e SAFIR, ambos baseados no método dos elementos finitos.

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Mashups are becoming increasingly popular as end users are able to easily access, manipulate, and compose data from several web sources. To support end users, communities are forming around mashup development environments that facilitate sharing code and knowledge. We have observed, however, that end user mashups tend to suffer from several deficiencies, such as inoperable components or references to invalid data sources, and that those deficiencies are often propagated through the rampant reuse in these end user communities. In this work, we identify and specify ten code smells indicative of deficiencies we observed in a sample of 8,051 pipe-like web mashups developed by thousands of end users in the popular Yahoo! Pipes environment. We show through an empirical study that end users generally prefer pipes that lack those smells, and then present eleven specialized refactorings that we designed to target and remove the smells. Our refactorings reduce the complexity of pipes, increase their abstraction, update broken sources of data and dated components, and standardize pipes to fit the community development patterns. Our assessment on the sample of mashups shows that smells are present in 81% of the pipes, and that the proposed refactorings can reduce that number to 16%, illustrating the potential of refactoring to support thousands of end users developing pipe-like mashups.

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Abstract The goal of this project is to evaluate the effectiveness of bioswells in protecting water quality from urban runoff. The hypothesis tested in this project is that water in bioswells improves water quality. Water quality in both a bioswell and an underground concrete lined ditch, both containing ground and surface water, were tested for certain water quality parameters. These parameters consisted of: Dissolved Oxygen, pH, water temperature, weather temperature, Total Dissolved Solids, Specific Conductivity, Alkalinity, Total Dissolved Carbon, Chemical Oxygen Demand, and depth and width of the sampling site. An additional contaminant that was looked at was motor oil. This was measured by comparing Total Organic Carbon with Chemical Oxygen Demand. A variety of different methods to measure the water quality parameters were utilized. The concrete site had more stable readings, but much higher water temperatures. However, the bioswell water is mainly from surface water runoff, and the underground concrete lined pipe is from underground water, so the two cannot be directly compared. The bioswell had high readings, especially pertaining to Oxygen Demand, Total Organic Carbon, and Specific Conductivity in early test dates. But, these readings improved as they were filtered though the bioswell. As plant activity increased and the weather began to warm up there were more stable readings. It is concluded that bioswells are an effective way to reduce problems associated with urban runoff pertaining to certain water quality parameters.

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Stage-structured models that integrate demography and dispersal can be used to identify points in the life cycle with large effects on rates of population spatial spread, information that is vital in the development of containment strategies for invasive species. Current challenges in the application of these tools include: (1) accounting for large uncertainty in model parameters, which may violate assumptions of ‘‘local’’ perturbation metrics such as sensitivities and elasticities, and (2) forecasting not only asymptotic rates of spatial spread, as is usually done, but also transient spatial dynamics in the early stages of invasion. We developed an invasion model for the Diaprepes root weevil (DRW; Diaprepes abbreviatus [Coleoptera: Curculionidae]), a generalist herbivore that has invaded citrus-growing regions of the United States. We synthesized data on DRW demography and dispersal and generated predictions for asymptotic and transient peak invasion speeds, accounting for parameter uncertainty. We quantified the contributions of each parameter toward invasion speed using a ‘‘global’’ perturbation analysis, and we contrasted parameter contributions during the transient and asymptotic phases. We found that the asymptotic invasion speed was 0.02–0.028 km/week, although the transient peak invasion speed (0.03– 0.045 km/week) was significantly greater. Both asymptotic and transient invasions speeds were most responsive to weevil dispersal distances. However, demographic parameters that had large effects on asymptotic speed (e.g., survival of early-instar larvae) had little effect on transient speed. Comparison of the global analysis with lower-level elasticities indicated that local perturbation analysis would have generated unreliable predictions for the responsiveness of invasion speed to underlying parameters. Observed range expansion in southern Florida (1992–2006) was significantly lower than the invasion speed predicted by the model. Possible causes of this mismatch include overestimation of dispersal distances, demographic rates, and spatiotemporal variation in parameter values. This study demonstrates that, when parameter uncertainty is large, as is often the case, global perturbation analyses are needed to identify which points in the life cycle should be targets of management. Our results also suggest that effective strategies for reducing spread during the asymptotic phase may have little effect during the transient phase. Includes Appendix.

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The Objective Structured Clinical Examination (OSCE) appears to be an effective alternative for assessing not only medical knowledge, but also clinical skills, including effective communication and physical examination skills. The purpose of the current study was to implement an OSCE model in a geriatrics fellowship program and to compare the instrument with traditional essay examination. Seventy first- and second-year geriatric fellows were initially submitted to a traditional essay examination and scored from 0 to 10 by a faculty member. The same fellows subsequently underwent an OSCE with eight 10-minute stations covering a wide range of essential aspects of geriatric knowledge. Each OSCE station had an examiner responsible for its evaluation according to a predefined checklist. Checklist items were classified for analysis purposes as clinical knowledge items (CKI) and communication skills items (CSI); fellow responses were scored from 0 to 10.Although essay examinations took from 30 to 45 minutes to complete, 180200 minutes were required to evaluate fellows using the proposed OSCE method. Fellows scored an average of 6.2 +/- 1.2 on the traditional essay examination and 6.6 +/- 1.0 on the OSCE (P < .001). Subanalyses of OSCE scores indicated that average performance on CKI was lower than the average on CSI (6.4 +/- 1.1 vs. 8.4 +/- 1.1; P < .001). Fellow performance on the essay examination was similar to their performance on CKI (P = .13). Second-year fellows performed better than first-year fellows on the essay examination (P < .001) and CKI (P = .05), but not on CSI (P = .25).The OSCE was successfully implemented as an educational strategy during a geriatrics fellowship program. Combining different testing modalities may provide the best assessment of competence for various domains of knowledge, skills, and behavior.

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Rapid decline in cell-wall digestibility hinders efficient use of warm-season grasses. The objective of this study was to identify genes whose expressions are related to the slope of decline in cell-wall digestibility. Eleven guineagrass genotypes were harvested at three ages and classified according to fibre digestibility. Extreme genotypes were separated into groups with either FAST or SLOW decline in fibre digestibility. Expression of transcripts from six genes from the lignin synthesis pathway was quantified by real-time PCR. Fast decline in fibre digestibility was associated with higher DM yield after 90 d of regrowth. Apart from lower fibre digestibility and higher lignin content for the FAST group, there were no other differences between the two groups for the chemical composition of stems and leaves. Maturity affected differently the expression of two of the six genes, cinnamate 4-hydroxylase and caffeoyl-CoA O-methyltransferase (C4H and CCoAOMT). Genotypes with fast decline in fibre digestibility had greater increase in the expression of C4H and CCoAOMT from 30 to 60 d of regrowth, than genotypes with slower decline. Expression of C4H and CCoAOMT appears to be related to the decline in cell-wall digestibility with advance in maturity of guineagrass.

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This paper estimates the impact of the use of structured methods on the quality of education for students in primary public school in Brazil. Structured methods encompass a range of pedagogical and managerial instruments applied in the educational system. In recent years, several municipalities in the state of Sao Paulo have contracted out private educational providers to implement these structured methods in their schooling systems. Their pedagogical proposal involves structuring of curriculum content, development of teacher and student textbooks, and the training and supervision of teachers anti instructors. Using a difference-in-differences estimation strategy, we find that the 4th- and 8th-grade students in the municipalities with structured methods performed better in Portuguese and mathematics than did students in municipalities not exposed to these methods. We find no differences in passing rates. A robustness test supports the assumption that there is no unobserved municipal characteristics associated with proficiency changes over time that may affect the results. (C) 2012 Elsevier Ltd. All rights reserved.

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The combination of solid-phase microextraction (SPME) with comprehensive two-dimensional gas chromatography is evaluated here for fatty acid (FA) profiling of the glycerophospholipid fraction from human buccal mucosal cells. A base-catalyzed derivatization reaction selective for polar lipids such as glycerophospholipid was adopted. SPME is compared to a miniaturized liquidliquid extraction procedure for the isolation of FA methyl esters produced in the derivatization step. The limits of detection and limits of quantitation were calculated for each sample preparation method. Because of its lower values of limits of detection and quantitation, SPME was adopted. The extracted analytes were separated, detected, and quantified by comprehensive two-dimensional gas chromatography with flame ionization detection (FID). The combination of SPME and comprehensive two-dimensional gas chromatography with FID, using a selective derivatization reaction in the preliminary steps, proved to be a simple and fast procedure for FA profiling, and was successfully applied to the analysis of adult human buccal mucosal cells.

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Prosthetic meshes are commonly used to correct abdominal wall defects. However, the inflammatory reaction induced by these devices in the peritoneum is not completely understood. We hypothesized that nitric oxide (NO), produced by nitric oxide synthase 2 (NOS2) may modulate the response induced by mesh implants in the abdominal wall and, consequently, affect the outcome of the surgical procedure. Polypropylene meshes were implanted in the peritoneal side of the abdominal wall in wild-type and NOS2-deficient (NOS2(-/-)) mice. After 15 days tissues around the mesh implant were collected, and inflammatory markers (the cytokine interleukin 1 beta (IL-1 beta) and NO) and tissue remodeling (collagen and metalloproteinases (MMP) 2 and 9) were analyzed. The lack of NOS2-derived NO induced a higher incidence of visceral adhesions at the mesh implantation site compared with wild-type mice that underwent the same procedure (P < 0.05). Additionally, higher levels of IL-1 beta were present in the mesh-implanted NOS2(-/-) animals compared with control and wild-type mice. Mesh implantation induced collagen I and III deposition, but in smaller amounts in NOS2(-/-) mice. MMP-9 activity after the surgical procedure was similarly increased in both groups. Conversely, MMP-2 activity was unchanged in mesh-implanted wild-type mice, but was significantly increased in NOS2(-/-) mice (P < 0.01), due to decreased S-nitrosylation of the enzyme in these animals. We conclude that NOS2-derived NO is crucial for an adequate response to and integration of polypropylene mesh implants in the peritoneum. NO deficiency results in a prolonged inflammatory reaction to the mesh implant, and reduced collagen deposition may contribute to an increased incidence of visceral adhesions. (C) 2011 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

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The theoretical E-curve for the laminar flow of non-Newtonian fluids in circular tubes may not be accurate for real tubular systems with diffusion, mechanical vibration, wall roughness, pipe fittings, curves, coils, or corrugated walls. Deviations from the idealized laminar flow reactor (LFR) cannot be well represented using the axial dispersion or the tanks-in-series models of residence time distribution (RTD). In this work, four RTD models derived from non-ideal velocity profiles in segregated tube flow are proposed. They were used to represent the RTD of three tubular systems working with Newtonian and pseudoplastic fluids. Other RTD models were considered for comparison. The proposed models provided good adjustments, and it was possible to determine the active volumes. It is expected that these models can be useful for the analysis of LFR or for the evaluation of continuous thermal processing of viscous foods.

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Objective Vasoactive intestinal peptide (VIP) is a neuropeptide with elevated expression in regions that control urogenital functions. Estrogen appears to modulate VIP expression in various organs, but this effect has not been demonstrated in the vaginal wall. The aim of this study was to evaluate the influence of estrogen status on VIP expression in vessels of the vaginal wall. Methods Surgical specimens were removed from the vaginal walls of 18 premenopausal women and 12 postmenopausal women who were given surgery for genital prolapse grade I or II. Vaginal specimens were stained with estrogen receptor-alpha (ER-alpha) and VIP antibodies. Levels of follicle stimulating hormone (FSH), estradiol, prolactin, fasting glucose and serum thyroxine stimulating hormone were also measured. Estrogen status was assessed on the basis of FSH and ER-alpha scores. Results The vaginal walls of premenopausal women had significantly higher ER-alpha scores than those of menopausal women (premenopausal group, 3.6 +/- 2.2; menopausal group, 1.4 +/- 1.8; p = 0.01). Premenopausal women also had significantly higher levels of VIP in the vaginal wall than menopausal women (p = 0.02). Increasing age was associated with lower level of VIP staining (odds ratio 0.88; 95% confidence interval 0.78-0.99). Conclusion Levels of ER-alpha and VIP expression in the posterior vaginal wall were higher in premenopausal than in menopausal women, but VIP expression was not associated with estrogen status. Age was an independent predictor of VIP staining in vaginal wall biopsies.