93 resultados para 378.861


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This paper presents research for developing a virtual inspection system that evaluates the dimensional tolerance of forged aerofoil blades formed using the finite element (FE) method. Conventional algorithms adopted by modern coordinate measurement processes have been incorporated with the latest free-form surface evaluation techniques to provide a robust framework for the dimensional inspection of FE aerofoil models. The accuracy of the approach had been verified with a strong correlation obtained between the virtual inspection data and coordinate measurement data from corresponding aerofoil components.

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The mixing of poly(methyl methacrylate) (PMMA) bone cement has been studied to develop methods for preparing a consistently high quality cement. A novel droplet test experimental procedure was developed that characterised the wetting characteristics involved in bone cement mixing. Using this technique it was established that increased wetting occurred by mixing bone cement at a lower temperature (-28 degreesC) than normal mixing at room temperature.

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This letter investigates the optimum decision delay and tap-length of the finite-length decision feedback equalizer. First we show that, if the feedback filter (FBF) length N-b is equal to or larger than the channel memory upsilon and the decision delay Delta is smaller than the feedforward filter (FFF) length N-f, then only the first Delta + 1 elements of the FFF can be nonzero. Based on this result we prove that the maximum effective FBF length is equal to the channel memory upsilon, and if N-b greater than or equal to upsilon and N-f is long enough, the optimum decision delay that minimizes the MMSE is N-f - 1.

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This study aimed to compare and contrast how midwives working in either hospital or community settings are currently responding to the cooccurrence of domestic and child abuse (CA), their perceived role and willingness to identify abuse, record keeping, reporting of suspected or definite cases of CA and training received. A survey questionnaire was sent to 861 hospital and community midwives throughout Northern Ireland which resulted in 488 midwives completing the questionnaire, leading to a 57% response rate. Comparisons were made using descriptive statistics and cross-tabulation, and the questionnaire was validated using exploratory factor analysis. Community midwives reported receiving more training on domestic and CA. Although a high percent of both hospital and community midwives acknowledged a link between domestic violence (DV) and CA, it was the community midwives who encountered more suspected and definite (P <0.001) cases of CA. More community midwives reported to be aware of the mechanisms for reporting CA. However, an important finding is that although 12% of community midwives encountered a definite case of CA, only 2% reported the abuse, leaving a 10% gap between reporting and identifying definite cases of CA. Findings suggest that lack of education and training was a problem as only a quarter of hospital-based midwives reported to have received training on DV and 40% on CA. This was significantly less than that received by community midwives, as 57% received training on DV, and 62% on CA. The study suggests that midwives need training on how to interact with abused mothers using non-coercive, supportive and empowering mechanisms. Many women may not spontaneously disclose the issues of child or domestic abuse in their lives, but often respond honestly to a sensitively asked question. This issue is important as only 13% of the sample actually asked a woman a direct question about DV.

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The comet assay is a technique used to quantify DNA damage and repair at a cellular level. In the assay, cells are embedded in agarose and the cellular content is stripped away leaving only the DNA trapped in an agarose cavity which can then be electrophoresed. The damaged DNA can enter the agarose and migrate while the undamaged DNA cannot and is retained. DNA damage is measured as the proportion of the migratory ‘tail’ DNA compared to the total DNA in the cell. The fundamental basis of these arbitrary values is obtained in the comet acquisition phase using fluorescence microscopy with a stoichiometric stain in tandem with image analysis software. Current methods deployed in such an acquisition are expected to be both objectively and randomly obtained. In this paper we examine the ‘randomness’ of the acquisition phase and suggest an alternative method that offers both objective and unbiased comet selection. In order to achieve this, we have adopted a survey sampling approach widely used in stereology, which offers a method of systematic random sampling (SRS). This is desirable as it offers an impartial and reproducible method of comet analysis that can be used both manually or automated. By making use of an unbiased sampling frame and using microscope verniers, we are able to increase the precision of estimates of DNA damage. Results obtained from a multiple-user pooled variation experiment showed that the SRS technique attained a lower variability than that of the traditional approach. The analysis of a single user with repetition experiment showed greater individual variances while not being detrimental to overall averages. This would suggest that the SRS method offers a better reflection of DNA damage for a given slide and also offers better user reproducibility.

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The particle size characteristics and encapsulation efficiency of microparticles prepared using triglyceride materials and loaded with two model water-soluble drugs were evaluated. Two emulsification procedures based on o/w and w/o/w methodologies were compared to a novel spray congealing procedure. After extensive modification of both emulsification methods, encapsulation efficiencies of 13.04% tetracycline HCl and 11.27% lidocaine HCl were achievable in a Witepsol (R)-based microparticle. This compares to much improved encapsulation efficiencies close to 100% for the spray congealing method, which was shown to produce spherical particles of similar to 58 mu m. Drug release studies from a Witepsol (R) formulation loaded with lidocaine HCl showed a temperature-dependent release mechanism, which displayed diffusion-controlled kinetics at temperatures similar to 25 degrees C, but exhibited almost immediate release when triggered using temperatures close to that of skin. Therefore, such a system may find application in topical semi-solid formulations, where a temperature-induced burst release is preferred.

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Aims: The aim of the study was to assess whether alcohol-related mortality data in the UK should be extended to include contributory as well as underlying cause of death. Methods: A total of 101,320 deaths registered in Northern Ireland between 2001 and 2007 were analysed to determine the quantity and characteristics of those with an underlying or contributory alcohol-related cause of death. Results: Alcohol was found to be an underlying cause of death in 1690 cases (1.7% of deaths) and a contributory cause in a further 1105 cases. Analyses show that the addition of alcohol-related contributory causes of deaths would increase the male-female ratio, result in steeper socio-economic gradients and amplify the apparent rate of increase of alcohol-related deaths. The significant contribution of alcohol to external causes of death, such as accidents and suicide, is also more evident. Conclusions: Using only underlying cause of death undoubtedly underestimates the burden of alcohol-related harm and may provide an inaccurate picture of those most likely to suffer from an alcohol-related death, especially among younger men.