997 resultados para Metallic part


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The tests that are currently available for the measurement of overexpression of the human epidermal growth factor-2 (HER2) in breast cancer have shown considerable problems in accuracy and interlaboratory reproducibility. Although these problems are partly alleviated by the use of validated, standardised 'kits', there may be considerable cost involved in their use. Prior to testing it may therefore be an advantage to be able to predict from basic pathology data whether a cancer is likely to overexpress HER2. In this study, we have correlated pathology features of cancers with the frequency of HER2 overexpression assessed by immunohistochemistry (IHC) using HercepTest (Dako). In addition, fluorescence in situ hybridisation (FISH) has been used to re-test the equivocal cancers and interobserver variation in assessing HER2 overexpression has been examined by a slide circulation scheme. Of the 1536 cancers, 1144 (74.5%) did not overexpress HER2. Unequivocal overexpression (3+ by IHC) was seen in 186 cancers (12%) and an equivocal result (2+ by IHC) was seen in 206 cancers (13%). Of the 156 IHC 3+ cancers for which complete data was available, 149 (95.5%) were ductal NST and 152 (97%) were histological grade 2 or 3. Only 1 of 124 infiltrating lobular carcinomas (0.8%) showed HER2 overexpression. None of the 49 'special types' of carcinoma showed HER2 overexpression. Re-testing by FISH of a proportion of the IHC 2+ cancers showed that only 25 (23%) of those assessable exhibited HER2 gene amplification, but 46 of the 47 IHC 3+ cancers (98%) were confirmed as showing gene amplification. Circulating slides for the assessment of HER2 score showed a moderate level of agreement between pathologists (kappa 0.4). As a result of this study we would advocate consideration of a triage approach to HER-2 testing. Infiltrating lobular and special types of carcinoma may not need to be routinely tested at presentation nor may grade 1 NST carcinomas in which only 1.4% have been shown to overexpress HER2. Testing of these carcinomas may be performed when HER2 status is required to assist in therapeutic or other clinical/prognostic decision-making. The highest yield of HER2 overexpressing carcinomas is seen in the grade 3 NST subgroup in which 24% are positive by IHC. (C) 2003 Elsevier Science Ltd. All rights reserved.

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A model of iron carbonate (FeCO3) film growth is proposed, which is an extension of the recent mechanistic model of carbon dioxide (CO2) corrosion by Nesic, et al. In the present model, the film growth occurs by precipitation of iron carbonate once saturation is exceeded. The kinetics of precipitation is dependent on temperature and local species concentrations that are calculated by solving the coupled species transport equations. Precipitation tends to build up a layer of FeCO3 on the surface of the steel and reduce the corrosion rate. On the other hand, the corrosion process induces voids under the precipitated film, thus increasing the porosity and leading to a higher corrosion rate. Depending on the environmental parameters such as temperature, pH, CO2 partial pressure, velocity, etc., the balance of the two processes can lead to a variety of outcomes. Very protective films and low corrosion rates are predicted at high pH, temperature, CO2 partial pressure, and Fe2+ ion concentration due to formation of dense protective films as expected. The model has been successfully calibrated against limited experimental data. Parametric testing of the model has been done to gain insight into the effect of various environmental parameters on iron carbonate film formation. The trends shown in the predictions agreed well with the general understanding of the CO2 corrosion process in the presence of iron carbonate films. The present model confirms that the concept of scaling tendency is a good tool for predicting the likelihood of protective iron carbonate film formation.

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Male kids (110) from six goat genotypes, i.e. Boer x Angora (BA), Boer x Feral (1317), Boer x Saanen (BS), Feral x Feral (FF), Saanen x Angora (SA) and Saanen x Feral (SF) and two slaughter weight groups, i.e. Capretto and Chevon (liveweight at slaughter 14-22 and 30-35 kg, respectively) were compared for growth, carcass and meat quality characteristics. Due to their better growth rate, kids from BS and SF genotypes reached the required liveweight for slaughter earlier than kids from other Genotypes used in the study. Chevon kids had a significantly (P < 0.05) lower average daily gain (119 g per day) compared to Capretto kids (171 g per day). SA, SF and FF kids deposited more internal fat in comparison to kids from other genotypes. The dressing percentage of kids ranged from 51 to 54%, with significant differences between genotypes. BS and SF kids had longer carcasses. while BF kids had larger eye muscle area compared to other genotypes. Goat carcasses had a thin subcutaneous fat cover (1.6-2.2 mm). Genotype had a significant (P < 0.05) influence on cooking loss, pigment concentration and muscle colour parameters (CIE L*, a* and b* values). As denoted by the higher V and fibre optic probe values and lower subjective muscle score, the longissimus muscle colour was lighter for BS kids than other genotypes. Cooked meat from the BF kids had lower shear force values and better sensory scores compared to other genotypes. A significant (P < 0.05) decrease in muscle tenderness was observed from Capretto to Chevon carcasses, whereas cooked meat from these two slaughter weight groups was equally accepted (P > 0.05) by the panellists. (C) 2003 Elsevier Science B.V. All rights reserved.

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The dissected carcass composition and fatty acid profiles of intermuscular fat from 110 male goat kids from six genotypes i.e. Boer x Angora (BA), Boer x Feral (BF), Boer x Saanen (BS), Feral x Feral (1717), Saanen x Angora (SA) and Saanen x Feral (SF) and two slaughter weight groups i.e. Capretto and Chevon (liveweight at slaughter 14-22 and 30-35 kg, respectively) were compared. Carcass tissue distribution for various genotypes was: muscle (63-66%), fat (10-13%) and bone (21-24%). Genotype significantly (P < 0.05) influenced the carcass composition; BA and FF carcasses had significantly higher muscle to bone ratio, while carcasses from BS kids were leaner compared to other genotypes. However, the two slaughter weight groups did not differ significantly (P > 0.05) in terms of carcass composition, when compared at the same carcass weight. In the present study, significant (P < 0.01) correlations were observed between percentage of muscle, fat and bone in most of the primal cuts and that in the carcass side. The main saturated fatty acids (SFAs) identified were palmitic (16:0) and stearic acid (18:0), while oleic acid (18: 1, omega9) was the main unsaturated fatty acid (UFA) in the intermuscular fat from goat kids. There were significant (P < 0.05) differences between genotypes in the proportions of individual fatty acids. Adipose tissue from BS kids had significantly higher UFAs (mainly oleic acid) and thus had a significantly lower melting point compared to other genotypes. There were significantly higher proportions of palmitic acid (35%) in the adipose tissue from Capretto kids compared to that from Chevon kids (22%). The concentration of UFAs increased in the adipose tissue from Capretto to Chevon carcasses. (C) 2003 Elsevier Science B.V. All rights reserved.

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For dynamic simulations to be credible, verification of the computer code must be an integral part of the modelling process. This two-part paper describes a novel approach to verification through program testing and debugging. In Part 1, a methodology is presented for detecting and isolating coding errors using back-to-back testing. Residuals are generated by comparing the output of two independent implementations, in response to identical inputs. The key feature of the methodology is that a specially modified observer is created using one of the implementations, so as to impose an error-dependent structure on these residuals. Each error can be associated with a fixed and known subspace, permitting errors to be isolated to specific equations in the code. It is shown that the geometric properties extend to multiple errors in either one of the two implementations. Copyright (C) 2003 John Wiley Sons, Ltd.

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In Part 1 of this paper a methodology for back-to-back testing of simulation software was described. Residuals with error-dependent geometric properties were generated. A set of potential coding errors was enumerated, along with a corresponding set of feature matrices, which describe the geometric properties imposed on the residuals by each of the errors. In this part of the paper, an algorithm is developed to isolate the coding errors present by analysing the residuals. A set of errors is isolated when the subspace spanned by their combined feature matrices corresponds to that of the residuals. Individual feature matrices are compared to the residuals and classified as 'definite', 'possible' or 'impossible'. The status of 'possible' errors is resolved using a dynamic subset testing algorithm. To demonstrate and validate the testing methodology presented in Part 1 and the isolation algorithm presented in Part 2, a case study is presented using a model for biological wastewater treatment. Both single and simultaneous errors that are deliberately introduced into the simulation code are correctly detected and isolated. Copyright (C) 2003 John Wiley Sons, Ltd.

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Raw milk was stored for 0, 2 and 4 days and processed in a UHT pilot plant by either direct or indirect heating. The unstored raw milk was also pasteurised. The thermally induced changes resulting from these treatments were investigated by examining a number of indices of heat damage. Lactulose, furosine, total and free hydroxymethylfurfural (HMF) and acid-soluble beta-lactoglobulin were analysed by high performance liquid chromatography (HPLC) while soluble tryptophan was examined by fluorescence spectroscopy. The directly heated UHT milk showed less heat damage than the indirectly heated milk, while the pasteurised milk displayed the least heat damage. During storage of the UHT milk for 12 weeks at similar to20degreesC, the levels of lactulose remained constant, while the furosine concentration increased. Both the total HMF and undenatured beta-lactoglobulin contents showed a general decrease during storage; however free HMF values initially rose but then decreased after four weeks' storage. As the age of the milk at the time of UHT processing increased, the levels of some of the indicators decreased. It is concluded that lactulose is the most reliable index of heat treatment, as it is virtually unaffected by refrigerated storage of the milk before or ambient storage after UHT processing. Reliance on other indicators may give misleading information on the heat load that UHT milk has received during processing.

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Within the development of motor vehicles, crash safety (e.g. occupant protection, pedestrian protection, low speed damageability), is one of the most important attributes. In order to be able to fulfill the increased requirements in the framework of shorter cycle times and rising pressure to reduce costs, car manufacturers keep intensifying the use of virtual development tools such as those in the domain of Computer Aided Engineering (CAE). For crash simulations, the explicit finite element method (FEM) is applied. The accuracy of the simulation process is highly dependent on the accuracy of the simulation model, including the midplane mesh. One of the roughest approximations typically made is the actual part thickness which, in reality, can vary locally. However, almost always a constant thickness value is defined throughout the entire part due to complexity reasons. On the other hand, for precise fracture analysis within FEM, the correct thickness consideration is one key enabler. Thus, availability of per element thickness information, which does not exist explicitly in the FEM model, can significantly contribute to an improved crash simulation quality, especially regarding fracture prediction. Even though the thickness is not explicitly available from the FEM model, it can be inferred from the original CAD geometric model through geometric calculations. This paper proposes and compares two thickness estimation algorithms based on ray tracing and nearest neighbour 3D range searches. A systematic quantitative analysis of the accuracy of both algorithms is presented, as well as a thorough identification of particular geometric arrangements under which their accuracy can be compared. These results enable the identification of each technique’s weaknesses and hint towards a new, integrated, approach to the problem that linearly combines the estimates produced by each algorithm.

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Foi desenvolvido um método destinado a fazer a triagem rápida e o escalonamento da toxicidade geral exercida por xenobióticos tendo como modelo o Saccharomyces cerevisiae. Para padronizar as condições de experimentação foi estabelecida a relação entre a absorvência a 525 nm e o número de células em suspensão por mililitro de meio de cultura e calculadas uma curva padrão e respectiva equação definidora (Y=6,8219E-08X + 0,0327) Culturas de Saccharomyces cerevisiae em meio completo para leveduras (YPD - 1% de glucose 2%, de peptona 0,5% e extracto de levedura 1%) foram expostas a diferentes concentrações de nicotina e a inibição do crescimento avaliada.

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O projecto “Principais tendências no cinema português contemporâneo” nasceu no Departamento de Cinema da ESTC, com o objectivo de desenvolver investigação especializada a partir de um núcleo formado por alunos da Licenciatura em Cinema e do Mestrado em Desenvolvimento de Projecto Cinematográfico, a que se juntaram professores-investigadores membros do CIAC e convidados. O que agora se divulga corresponde a dois anos e meio de trabalho desenvolvido pela equipa de investigação, entre Abril de 2009 e Novembro de 2011. Dada a forma que ele foi adquirindo, preferimos renomeá-lo, para efeitos de divulgação, “Novas & velhas tendências no cinema português contemporâneo”.

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During the last two decades screen-film (SF) systems have been replaced by digital X-ray systems. The advent of digital technologies brought a number of digital solutions based on different detector and readout technologies. Improvements in technology allowed the development of new digital technologies for projection radiography such as computed radiography (CR) and digital radiography (DR). The large number of scientific papers concerning digital X-ray systems that have been published over the last 25 years indicates the relevance of these technologies in healthcare. There are important differences among different detector technologies that may affect system performance and image quality for diagnostic purposes. Radiographers are expected to have an effective understanding of digital X-ray technologies and a high level of knowledge and awareness concerning the capabilities of these systems. Patient safety and reliable diagnostic information are intrinsically linked to these factors. In this review article - which is the first of two parts - a global overview of the digital radiography systems (both CR and DR) currently available for clinical practice is provided.

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Digital X-ray detector technologies provide several advantages when compared with screen-film (SF) systems: better diagnostic quality of the radiographic image, increased dose efficiency, better dynamic range and possible reduction of radiation exposure to the patient. The transition from traditional SF systems to digital technology-based systems highlights the importance of the discussion around technical factors such as image acquisition, themanagement of patient dose and diagnostic image quality. Radiographers should be aware of these aspects concerning their clinical practice regarding the advantages and limitations of digital detectors. Newdigital technologies require an up-to-date of scientific knowledge concerning their use in projection radiography. This is the second of a two-part review article focused on a technical overview of digital radiography detectors. This article provides a discussion about the issues related to the image acquisition requirements and advantages of digital technologies, the management of patient dose and the diagnostic image quality.

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Trabalho Final de Mestrado para obtenção do grau de Mestre em Engenharia de Electrónica e Telecomunicações

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O presente trabalho visa propor uma estratégia para a construção e lançamento de um novo modelo de negócio para a atuação das Relações Públicas em Portugal, numa proposta direcionada para as micro e pequenas empresas. Entre o serviço in house e a consultadoria clássica existe um espaço não coberto em Portugal: um serviço in house partilhado. Apresenta-se aqui este projeto de serviço de Relações Públicas para aqueles para quem é incomportável assumir nos seus quadros um Técnico de Comunicação.