964 resultados para Methods Time Measurement (MTM)


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Este artículo enfoca eltrabajo docente enlas universidades públicas provincialesdel Paraná/Brasil. Inicialmente se problematiza loactual contexto marcado por la restructuraciónproductiva y por la reforma de Estado y lastransformaciones por lascualesvienepasandolauniversidadbrasileña. A partir de ahíelestudio se vuelve para el cotidiano docente mediante entrevistas realizadas contreinta y seis docentes vinculados latres universidades públicas provinciales. Se analizalas entrevistas hechasconlos docentes y se discute tendencias observadas enlosdatoscolectados. Se postula laconstitución de una nueva métrica deltiempo y una nuevaespacializacióneneltrabajo docente resultante de loscambiospolítico-económicos, cuya tónica es la gradual exencióndelfinanciamiento público y lacomercializacióndelconocimiento a través de laprivatización de cursos y de lainnovación tecnológica subordinada. Se aborda algunasrepercusiones de las condiciones objetivas sobre lasactividades académico-científicas y políticas delcuerpo de profesores como elenvolvimiento de este conprácticasdelcasi mercado educacional, la falta de tiempo para eltrabajo de cuño intelectual y elvaciamiento de la política sindical

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Este artículo enfoca eltrabajo docente enlas universidades públicas provincialesdel Paraná/Brasil. Inicialmente se problematiza loactual contexto marcado por la restructuraciónproductiva y por la reforma de Estado y lastransformaciones por lascualesvienepasandolauniversidadbrasileña. A partir de ahíelestudio se vuelve para el cotidiano docente mediante entrevistas realizadas contreinta y seis docentes vinculados latres universidades públicas provinciales. Se analizalas entrevistas hechasconlos docentes y se discute tendencias observadas enlosdatoscolectados. Se postula laconstitución de una nueva métrica deltiempo y una nuevaespacializacióneneltrabajo docente resultante de loscambiospolítico-económicos, cuya tónica es la gradual exencióndelfinanciamiento público y lacomercializacióndelconocimiento a través de laprivatización de cursos y de lainnovación tecnológica subordinada. Se aborda algunasrepercusiones de las condiciones objetivas sobre lasactividades académico-científicas y políticas delcuerpo de profesores como elenvolvimiento de este conprácticasdelcasi mercado educacional, la falta de tiempo para eltrabajo de cuño intelectual y elvaciamiento de la política sindical

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The application of Rheology to study biological systems is a new and very extensive matter, in which melon is absolutely unknown. The goal of this work is to determine some physical characteristics of this fruit, immediately after harvest and during its conservation in cold storage. Portugal and Spain are the most interested countries in these studies, as they are important producers of melon. The varieties Branco da Leziria and Piel de sapo were chosen because they are the most popular in both countries. The fruit were studied on the day they were harvested, and then were conserved in cold storage in the "Instituto del Frio" in Madrid, and they were periodically tested again. Thus during seven days the same fruits, and new fruits, were picked up and tested. On the first day of testing we had 20 fruits to study and at the end of the testing period we had used 80 fruits. The results from the non-destructive impact test were very significant and they may contribute to standardise methods to measure fruit maturity. These results were confirmed by those obtained from compression tests. The results obtained during the Impact tests with melon were similar to those obtained previously with other fruits. There is a close relationship between the results of the Impact tests and Compression tests. Tests like Impact and Compression can be adapted to melon, varieties 'Piel de Sapo" and 'Branco de Leziria', allowing us to continue further work with this species. The great number of data obtained during performance of the tests allowed us to go on with this work and to contribute to standardise methods of measurement and expression of characteristics of a new biological product. During the "Impact damage in fruits and vegetables" workshop, held in Zaragoza in 1990, these matters were included in the priority list.

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El ruido es un contaminante que cada vez va tomando más importancia por ser un tipo de contaminación propio de las sociedades modernas. Su estudio en tanto su origen y efectos en la población, ha sido objeto de numerosas líneas de investigación en el mundo, siendo una de las herramientas más utilizadas las encuestas de percepción de molestias realizadas en numerosos países y de variados diseños metodológicos. Sin embargo, la profusa información recolectada por muchos años y por distintos países por medio de estas herramientas no permite obtener datos relacionados entre ellos para estudiar las distintas condiciones de exposición a distintos tipos de fuentes de ruido, dado que responden a diseños de instrumentos de recolección de datos (encuestas) distintos y, aún más, a escalas de mediciones distintas. Un esfuerzo por generar datos y estudios que puedan ser relacionados para contribuir a mayor conocimiento del ruido y sus efectos en la salud de la población, es la iniciativa desarrollada por el ICBEN (International Commission of Biological Effects on Noise) que desde el año 1997 un grupo de investigadores se ha propuesto generar estudios e investigaciones bajo una metodología que permita comparar los diferentes estudios que se realicen y que sus conclusiones permitan ser utilizadas por el resto y así generar nuevos conocimientos y validar dichos resultados. Uno de los problemas que en la actualidad se tiene es que las encuestas que se utilizan en distintos países, e incluso en ellos mismos, no sólo incorporan preguntas de diversas modalidades y estilos, sino que además para las respuestas que entregan los encuestados se utilizan una variedad de métodos y escalas que no permiten ser extrapolados o comparados con otros estudios. Dado que las escalas que algunos estudios utilizan, para conocer el grado de molestia que presenta la población, sin verbales, las líneas de investigación y recomendaciones internacionales sugieren que cada país desarrolle sus propias escalas y que no se remitan sólo a traducir aquellas utilizadas en otros idiomas. Esto debido que cada palabra que se utilice en las escalas encierra un concepto metrológico, esto es, que las personas le asignan un valor específico de intensidad en el continuo de grados de molestia, por lo que deben ser obtenidas para cada población bajo estudio. Esta investigación, siguiendo las recomendaciones internacionales, ha obtenido una escala verbal para ser utilizada en encuestas de percepción subjetiva de molestias por ruido en Chile, para una población de entre 15 a 65 años de edad. Se ha podido desarrollar un test para obtener dicha escala siguiendo la metodología internacional, lo que ha permitido además discutir y analizar su utilización en futuras investigaciones. Del mismo modo, se ha podido analizar la equivalencia que tiene con otras escalas que podrían ser obtenidas con esta misma metodología, así como la escala que la recomendación internacional ISO propone para el idioma español. Los resultados obtenidos permiten comprobar la necesidad de que cada país hispanoparlante desarrolle sus propias escalas lo que podría explicar, entre otros aspectos, del por qué la norma internacional aún no tiene características de oficial a falta de mayor consenso en la comunidad científica, por lo que los datos aportados en esta investigación permitirán profundizar estos y otros aspectos a los investigadores en esta materia. ABSTRACT Noise is considered as a pollutant that it is growing in importance because it has become recognized as a major annoyance in modern societies. The study of its origin and effects on populations has been the objective of numerous lines of investigation all over the world. The annoyance questionnaire is a tool that is frequently utilized in numerous countries using a variety of design methods. Nevertheless, the quantity of information collected over several years in different countries using these tools has not allowed an interrelated correlation of data because the data indicates that the different study tools designed to collect data have used varying collection techniques and measurement scales that define the exposure to different types and sources of noise pollution. In an effort to generate data and studies then can be combined to better the understanding of noise and its effects on public health, an initiative that was developed by ICBEN (International Commission of Biological Effects on Noise) was proposed in 1997 and is designed to generate and investigate studies under methodologies that allow the comparisons of different studies already undertaken and the coordination of their conclusions. These investigative tools can be used by other investigators who will be able to generate additional information and validates results. One of the currently existing problems is that the questionnaires utilized by different countries and within the same countries not only use questions based on different models and styles, but also the answers given by the subjects being interviewed are interpreted using different methods and measurement scales which do not permit direct comparison of relationship with other studies. Given the measurement tools used to obtain the reported levels of annoyance that the population experiences (without verbal response) the lines of investigation and international recommendations are that each country develops its own scale that does not rely only on verbal responses in the corresponding language. This is because each word utilized in the measurement scale has a numeric concept with which interview subjects will assign a specific numeric intensity from the continuum of levels of annoyance and must be obtained for each population under study. This investigation, which follows international recommendations, has obtained a verbal scale to be utilized in subjective perception questionnaires of noise annoyance in Chile, for a subject population of subjects between 15 and 65 years of age. It has been able to develop a test to obtain said measurement scale following the international methodology guidelines which has permitted discussion and analysis of their use by other investigators. By the same token, it has been possible to analyze the equivalency that exists between other scales that could be obtained with the same methodology including the scale as recommended by international ISO for Spanish Language. The results obtained allows proof of the necessity that each Spanish Speaking Country develop their own measurement scales which could explain, the reason why the international norm still does not have the official characteristics because of a failure of a majority consensus in the scientific community, by which the data contribution from this investigation will allow the investigator to deepen these and other aspects of the subject.

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Este proyecto está dividido en dos partes, una de ellas dedicada al estudio del sistema de adquisición NetdB y su aplicación a prácticas de Acústica Arquitectónica y la otra dedicada a la evaluación de la herramienta OneNote 2010 y su aplicación al proceso enseñanza – aprendizaje. Se estructura en cinco secciones bien definidas que se comentan a continuación: La primera sección, fundamentos teóricos, se centrará en explicar los distintos parámetros medidos y su relación con la acústica. Para ello se definirán los conceptos teóricos básicos que ayudarán al seguimiento del proyecto en su totalidad. La segunda sección está dedicada al sistema de adquisición NetdB, y en ella se explican sus características, el conexionado del equipo y la configuración del mismo con el software dBBati. En la tercera sección se describen las medidas realizadas con el sistema de adquisición NetdB, basadas en la normativa nacional e internacional vigente. Estas medidas son: - Medición del tiempo de reverberación en recintos ordinarios, según la Norma UNE-EN ISO 3382-2. - Medición del coeficiente de absorción sonora en cámara reverberante, según la Norma UNE-EN ISO 354. - Medición “in situ” del aislamiento a ruido aéreo, según las normas UNE-EN ISO 140-4 y UNE-EN ISO 717-1. En cada una de las medidas se describe el objetivo, los equipos utilizados, la conexión entre los distintos equipos, el ensayo realizado según la norma correspondiente, los cálculos y resultados obtenidos y las conclusiones finales de la medida. En la cuarta sección se describe la herramienta OneNote 2010, detallándose su estructura, configuración y la evaluación de su aplicación al proceso enseñanza – aprendizaje. Por último, se darán unas conclusiones finales, en las que se recapitularán los resultados de las valoraciones obtenidos durante la realización del proyecto. ABSTRACT. This project is divided into two parts, one of them dealing with the study of NetdB acquisition system and its application on Architectural Acoustics practices and the other dedicated to the evaluation of the OneNote 2010 tool and its application on the teaching-learning process. The structure of the project consists of five clearly defined sections as stated hereunder: 1. Theoretical fundamentals, based on the explanation of the different parameters subject to measurement and their relation to acoustics. To this end, basic theoretical concepts will be clearly defined, which will help the follow-up of the project as a whole. 2. NetdB acquisition system: whereby features will be clearly defined, as well as the equipment connection and its configuration within the dBBati software. 3. Description of the measures carried out on the NetdB acquisition system under current regulations both national and international, being those measures as follows: - Reverberation Time measurement in ordinary premises, according to the UNE-EN ISO 3382-2 standard. - Sound absorption ratio measurement in reverberating chamber, according to the UNE-EN ISO 354 standard. - “In situ” sound proofing air traffic, according to UNE-EN ISO 140-4 and UNE-EN ISO 717-1 standards. Each of the measures stated above comprises the description of the following issues: its aim, the equipment in use, the connection among different equipment, the test carried out under the corresponding standard, the calculations and results obtained and finally the conclusions reached at. 4. OneNote 2010 tool: full description detailing its structure, configuration as well as the evaluation of its application on the teaching-learning process. Finally, the report will give the final conclusions by means of recapitulating the results of the different assessments obtained along the process.

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Seasonal changes of daylength (photoperiod) affect the expression of hormonal and behavioral circadian rhythms in a variety of organisms. In mammals, such effects might reflect photoperiodic changes in the circadian pace-making system [located in the suprachiasmatic nucleus (SCN) of the hypothalamus] that governs these rhythms, but to date no functionally relevant, intrinsic property of the SCN has been shown to be photoperiod dependent. We have analyzed the temporal regulation of light-induced c-fos gene expression in the SCN of rats maintained in long or short photoperiods. Both in situ hybridization and immunohistochemical assays show that the endogenous circadian rhythm of light responsiveness in the SCN is altered by photoperiod, with the duration of the photosensitive subjective night under the short photoperiod 5-6 h longer than under the long photoperiod. Our results provide evidence that a functional property of the SCN is altered by photoperiod and suggest that the nucleus is involved in photoperiodic time measurement.

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Purpose: The aim of this study is to determine the reliability of corneal thickness measurements derived from SOCT Copernicus HR (Fourier domain OCT). Methods: Thirty healthy eyes of 30 subjects were evaluated. One eye of each patient was chosen randomly. Images were obtained of the central (up to 2.0 mm from the corneal apex) and paracentral (2.0 to 4.0 mm) cornea. We assessed corneal thickness (central and paracentral) and epithelium thickness. The intra-observer repeatability data were analysed using the intra-class correlation coefficient (ICC) for a range of 95 per cent within-subject standard deviation (SW) and the within-subject coefficient of variation (CW). The level of agreement by Bland–Altman analysis was also represented for the study of the reproducibility between observers and agreement between methods of measurement (automatic versus manual). Results: The mean value of the central corneal thickness (CCT) was 542.4 ± 30.1 μm (SD). There was a high intra-observer agreement, finding the best result in the central sector with an intra-class correlation coefficient of 0.99, 95 per cent CI (0.989 to 0.997) and the worst, in the minimum corneal thickness, with an intra-class correlation coefficient of 0.672, 95 per cent CI (0.417 to 0.829). Reproducibility between observers was very high. The best result was found in the central sector thickness obtained both manually and automatically with an intra-class correlation coefficient of 0.990 in both cases and the worst result in the maximum corneal thickness with an intra-class correlation coefficient of 0.827. The agreement between measurement methods was also very high with intra-class correlation coefficient greater than 0.91. On the other hand the repeatability and reproducibility for epithelial measurements was poor. Conclusion: Pachymetric mapping with SOCT Copernicus HR was found to be highly repeatable and reproducible. We found that the device lacks an appropriate ergonomic design as proper focusing of the laser beam onto the cornea for anterior segment scanning required that patients were positioned slightly farther away from the machine head-rest than in the setup for retinal imaging.

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Background: In early 2001 Australia experienced a sudden and unexpected disruption to heroin availability, know as the 'heroin shortage'. This 'shortage has been linked to a decrease in needle and syringe output and therefore possibly a reduction in injecting drug use. We aimed to examine changes, if any, in blood-borne viral infections and presentations for injecting related problems related to injecting drug use following the reduction heroin availability in Australia, in the context of widespread harm reduction measures. Methods: Time series analysis of State level databases on HIV, hepatitis B, hepatitis C notifications and hospital and emergency department data. Examination of changes in HIV, hepatitis B, hepatitis C notifications and hospital and emergency department admissions for injection-related problems following the onset of the heroin shortage; non-parametric curve-fitting of number of hepatitis C notifications among those aged 15 - 19 years. Results: There were no changes observed in hospital visits for injection-related problems. There was no change related to the onset heroin shortage in the number of hepatitis C notifications among persons aged 15 - 19 years, but HCV notifications have subsequently decreased in this group. No change occurred in HIV and hepatitis B notifications. Conclusion: A marked reduction in heroin supply resulted in no increase in injection-related harm at the community level. However, a delayed decrease in HCV notifications among young people may be related. These changes occurred in a setting with widespread, publicly funded harm reduction initiatives.

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The importance of availability of comparable real income aggregates and their components to applied economic research is highlighted by the popularity of the Penn World Tables. Any methodology designed to achieve such a task requires the combination of data from several sources. The first is purchasing power parities (PPP) data available from the International Comparisons Project roughly every five years since the 1970s. The second is national level data on a range of variables that explain the behaviour of the ratio of PPP to market exchange rates. The final source of data is the national accounts publications of different countries which include estimates of gross domestic product and various price deflators. In this paper we present a method to construct a consistent panel of comparable real incomes by specifying the problem in state-space form. We present our completed work as well as briefly indicate our work in progress.

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Introduction – Why do we need ‘biomarkers? Biomarkers of protein oxidation Introduction Major issues/questions Protein carbonyl biomarkers Biochemistry Methods of measurement Storage, stability and limitations in use Protein thiol biomarkers Biochemistry Methods of measurement Storage, stability and limitations on use Aliphatic amino acid biomarkers Biochemistry Methods of measurement Storage, stability and limitations on use Oxidised Tryptophan Biomarkers Biochemistry Method of measurement Storage, stability and limitations on use Oxidised tyrosine biomarkers Biochemistry Methods of measurement Storage, stability and limitations on use Formation of neoepitopes on oxidised proteins Validation of assays for protein oxidation biomarkers Relationship of protein oxidation to disease Modulation of protein oxidation biomarkers by antioxidants Future perspectives Introduction to lipid peroxidation biomarkers Introduction: biochemistry of lipid peroxidation Malondialdehyde Methods of measurement Storage, stability and limitations on use Conjugated dienes Method of measurement Storage, stability and limitations of use LDL lag phase Method of measurement Storage, stability and limitations of use Hydrocarbon gases Biochemistry Method of measurement Storage, stability and limitations on use Lipofuscin Biochemistry Method of measurement Storage, stability and limitation on use Lipid peroxides Biochemistry Method of measurement Storage, stability and limitations on use Isoprostanes Biochemistry Method of measurement Storage, stability and limitations on use Possible new biomarkers of lipid oxidation Relationship of lipid peroxidation to disease Modulation of lipid peroxidation biomarkers by antioxidants Functional consequences of lipid peroxidation Contribution of dietary intake to lipid peroxidation products Biomarkers of DNA oxidation Introduction Confounding factors Units and terminology Nuclear and mitochondrial DNA damage Lymphocytes as surrogate tissues Measurement of DNA damage with the comet assay Practical details Storage, stability, and limitations of the assay Measurement of DNA base oxidation by HPLC Practical details Storage, stability and limitations of the method Measurement of DNA base oxidation by GC–MS Biochemistry of 8-oxoguanine, adenine and fapy derivatives Methods of measurement Storage, stability and limitations of the method Analysis of guanine oxidation products in urine Method of measurement Limitations and criticisms Immunochemical methods Methods of measurement Storage, stability, and limitations of the assay 32P post-labelling Method of measurement Limitations and criticisms Validation of assays for DNA oxidation Oxo-dGuo in lymphocyte DNA Urinary measurements DNA–aldehyde adducts Biochemistry Method of measurement Products of reactive nitrogen species Endpoints arising from oxidative DNA damage Mutations Chromosome aberrations Micronuclei Site-specific DNA damage Relationship of DNA oxidation to disease Modulation of DNA oxidation biomarkers by antioxidants Direct and indirect effects of oxidative stress: measures of total oxidant/antioxidant levels Visualisation of cellular oxidants Biochemistry: histochemical detection of ROS Method of measurement Limitations, storage and stability Measurement of hydrogen peroxide Biochemistry Methods of measurement Storage, stability and limitations on use Measurement of the ratio of antioxidant/oxidised antioxidant Biochemistry Method of measurement Storage, stability and limitations on use Total antioxidant capacity Biochemistry Terminology Methods of measurement Storage, stability and limitations on use Validation of assays for direct oxidant and antioxidant biomarkers Relationship of oxidant/antioxidant measurement to disease Modulation of oxidant/antioxidant biomarkers by dietary antioxidants Induction of genes in response to oxidative stress Background Measurement of antioxidant responsive genes and proteins Effects of antioxidant intake on the activity of antioxidant enzymes

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Pin on disc wear machines were used to study the boundary lubricated friction and wear of AISI 52100 steel sliding partners. Boundary conditions were obtained by using speed and load combinations which resulted in friction coefficients in excess of 0.1. Lubrication was achieved using zero, 15 and 1000 ppm concentrations of an organic dimeric acid additive in a hydrocarbon base stock. Experiments were performed for sliding speeds of 0.2, 0.35 and 0.5 m/s for a range of loads up to 220 N. Wear rate, frictional force and pin temperature were continually monitored throughout tests and where possible complementary methods of measurement were used to improve accuracy. A number of analytical techniques were used to examine wear surfaces, debris and lubricants, namely: Scanning Electron Microscopy (SEM), Auger Electron Spectroscopy (AES), Powder X-ray Diffraction (XRD), X-ray Photoelectron Spectroscopy (XPS), optical microscopy, Back scattered Electron Detection (BSED) and several metallographic techniques. Friction forces and wear rates were found to vary linearly with load for any given combination of speed and additive concentration. The additive itself was found to act as a surface oxidation inhibitor and as a lubricity enhancer, particularly in the case of the higher (1000 ppm) concentration. Wear was found to be due to a mild oxidational mechanism at low additive concentrations and a more severe metallic mechanism at higher concentrations with evidence of metallic delamination in the latter case. Scuffing loads were found to increase with increasing additive concentration and decrease with increasing speed as would be predicted by classical models of additive behaviour as an organo-metallic soap film. Heat flow considerations tended to suggest that surface temperature was not the overriding controlling factor in oxidational wear and a model is proposed which suggests oxygen concentration in the lubricant is the controlling factor in oxide growth and wear.

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The thesis investigates two different in vitro aspects of Chlamydia trachomatis (CT). The thesis analyzes the effect of different sugars on CT infectivity. which is investigated on HeLa cells after 2 hour-incubation of elementary bodies (EBs) with glucose, sucrose or mannitol. Sugars effect on EB membrane fluidity is investigated by fluorescence anisotropy measurement, whereas changes in lipopolysaccharide exposure are examined by cytofluorimetric analysis. By Western blot experiments, the phosphorylation state of Focal Adhesion Kinase in cells infected with EBs pre-incubated with sugars it’s explored. Sugar significantly increase infectivity, acting on the EB structure. Sugars induce an increase of EB membrane fluidity, leading to changes in LPS exposure. After incubation with sucrose and mannitol, EBs lead to higher FAK phosphorylation, enhancing activation of anti-apoptotic and proliferative signals in the host. Secondly, the thesis explores the protective effect of different Lactobacilli against CT infection: Lactobacillus crispatus and Lactobacillus reuteri. CT infectivity is evaluated after host cells were treated for 1 hour with diluted supernatant cell-free fraction or with the bacterial cells. Assessed that L.crispatus is more protective than L.reuteri, lactic acid production is evaluated by HPLC. Subsequently Lactate dehydrogenases activity is evaluated by resazurin assay and by LC-MS. Then, D-lactate dehydrogenase specific activity has been investigated by measuring NADH formation. Afterwards, addition of D or L-lactic acid to L.reuteri supernatant has been performed and their effect in promoting protection in the host cells assessed. Then a metabolic analysis has been carried out by real-time measurement of mitochondrial respiration after treatment. Finally, histone acetylation and lactylation, and gene and protein expression of relevant targets, have been investigated. It is shown that the D isomer is more efficient in conferring protection, causing a shift in the host cell metabolic profile and a pattern of histone modifications that changes the expression of important targets.