882 resultados para mixed stock analysis
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OBJECTIVES: To describe disease characteristics and treatment modalities in a multidisciplinary cohort of systemic lupus erythematosus (SLE) patients in Switzerland. METHODS: Cross-sectional analysis of 255 patients included in the Swiss SLE Cohort and coming from centres specialised in Clinical Immunology, Internal Medicine, Nephrology and Rheumatology. Clinical data were collected with a standardised form. Disease activity was assessed using the Safety of Estrogens in Lupus Erythematosus National Assessment-SLE Disease Activity Index (SELENA-SLEDAI), an integer physician's global assessment score (PGA) ranging from 0 (inactive) to 3 (very active disease) and the erythrocyte sedimentation rate (ESR). The relationship between SLE treatment and activity was assessed by propensity score methods using a mixed-effect logistic regression with a random effect on the contributing centre. RESULTS: Of the 255 patients, 82% were women and 82% were of European ancestry. The mean age at enrolment was 44.8 years and the median SLE duration was 5.2 years. Patients from Rheumatology had a significantly later disease onset. Renal disease was reported in 44% of patients. PGA showed active disease in 49% of patients, median SLEDAI was 4 and median ESR was 14 millimetre/first hour. Prescription rates of anti-malarial drugs ranged from 3% by nephrologists to 76% by rheumatologists. Patients regularly using anti-malarial drugs had significantly lower SELENA-SLEDAI scores and ESR values. CONCLUSION: In our cohort, patients in Rheumatology had a significantly later SLE onset than those in Nephrology. Anti-malarial drugs were mostly prescribed by rheumatologists and internists and less frequently by nephrologists, and appeared to be associated with less active SLE.
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The present study examined the bullying experiences of a group of students, age 10-14 years, identified as having behaviour problems. A total often students participated in a series of mixed methodology activities, including self-report questionnaires, story telling exercises, and interview style joumaling. The main research questions were related to the prevalence of bully/victims and the type of bullying experiences in this population. Questionnaires gathered information about their involvement in bullying, as well as about psychological risk factors including normative beliefs about antisocial acts, impulsivity, problem solving, and coping strategies. Journal questions expanded on these themes and allowed students to explain their personal experiences as bullies and victims as well as provide suggestions for intervention. The overall results indicated that all of the ten students in this sample have participated in bullying as both a bully and a victim. This high prevalence of bully/victim involvement in students from behavioural classrooms is in sharp contrast with the general population where the prevalence is about 33%. In addition, a common thread was found that indicated that these students who participated in this study demonstrate characteristics of emotionally dysregulated reactive bullies. Theoretical implication and educational practices are discussed.
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Adult-organized children's sport attracts millions of participants in Canada and the United States each year. Though there is a great deal of research that considers children's sport, little of it focuses on recreational or house league sport and less of it offers a deep examination of children's experience of their participation. Using observations, interviews, and focus groups involving ten participants in mixed-gender recreational basketball, this qualitative research project examined their experiences. With Foucault's concepts of correct training and the panoptic gaze in mind, I used discourse and deconstruction analyses to consider the children's descriptions along with my observations of their basketball experience. I was particularly looking for prevalent discourses on sport, childhood, and gender and how they affected their experiences. Despite the league's discursive emphasis on fun, participation, fairness, and respect, that was not necessarily what the children experienced. While most stated they enjoyed their season many also expressed serious disappointments. Size and particularly skill very much determined who was most involved in the action and thus actually played baskethaW. Gender also played a significant role in their sport experiences. My findings invite questions about what genuine sport participation actually is and how it might be alternatively imagined.
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A strain of Drosophila melanogaster (mid america stock culture no. hl16) has been reported to be deficient in aldehyde oxidase activity (Hickey and Singh 1982). This strain was characterized during the course of this study and compared to other mutant strains known to be deficient in aldehyde oxidase activity. During the course of this investigation, the hl16 strain was found to be temperature sensitive in its viability. It was found that the two phenotypes, the enzyme deficiency, and the temperature sensitive lethality were the result of two different mutations, both mapping to the X-chromosome. These two mutations were found to be separable by recombination. The enzyme deficiency was found to map to the same locus as the cinnamon mutation, another mutation which affects aldehyde oxidase production. The developmental profile of aldehyde oxidase in the hl16 strain was compared to the developmental profile in the Canton S wild type strain. The aldehyde oxidase activity in adult hl16 individuals was also compared to that of various other strains. It was also found that the aldehyde oxidase activity was temperature sensitive in the adult flies. The temperature sensitive lethality mutation was mapped to position 1-0.1.
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This study explores the perceptions and experiences of middle-class women, mostly mothers, regarding the elementary school education of their children of mixed heritage. Because it endeavours to provide a forum in which the voices of women are considered a source of valuable information for educators, this study contributes to the fields of feminist and mothering research. Participants assign meanings to their lived experiences (Schon, 1983; van Manen 1997) and contemplate the various ways in which a mixed heritage mayor may not affect a child's schooling. Four main participants were interviewed who are mothers whose children of mixed heritage presently attend public elementary schools in Ontario, Canada. The study had an emergent design, thus allowing the researcher to make decisions as the study progressed. Three additional participants were included in the study to provide a wider perspective on the topic. These 3 additional women were the researcher herself as she explored her self-conceptual baggage (Kirby & McKenna. 1989); the researcher's mother in an attempt to consider the motherline (Lowinsky, 1992); and a volunteer non-mother of mixed ethnicity. The study involved a total of 12 individual interviews of approximately 2 hours in length. The 4 main participants and the researcher were each interviewed twice; the researcher's mother and the volunteer non-mother were each interviewed once. The researcher also attempted a focus group and kept a journal throughout the research process. Much of the analysis centers on women's interpretations of the mixed heritage experience and on their suggestions for elementary school educators. It concludes pondering on the invisibility (Chiong, 1998) of such children within the school system and calling for increased teacher education as a way to bring the mixed heritage experience out of the shadows.
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Female enthusiasm towards engaging in physical education (PE) significantly decreases with age as it provides females with positive and negative emotional experiences. This study examined emotions within four grade nine female PE soccer and fitness classes (N = 67). Emotional patterns were studied over time and across two units of instruction and in relation to student grades. A mixed-method approach was utilized assessing the state emotions of shame, enjoyment, anxiety, and social physique anxiety (SPA). Results revealed unsatisfactory internal consistency for shame and thus it was removed. Statistical analysis revealed no significant changes in emotions over time, whereas qualitative analysis found that state emotions were inconsistent. Statistical analysis indicated that students in the fitness classes reported significantly higher levels of anxiety and SPA on the final class (p < .01). Qualitative analysis signaled different origins and themes of students‟ emotions. No predictive relationship between emotion and students‟ grade was found.
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This thesis examines the impact of a corporate name change on stock price and trading volume of Canadian companies around the announcement date, the approval date, and the adoption date over the time period from 1997 to 2011. Name changes are classified into six categories: major and minor, structural and pure, diversified and focused, accompanied with a change in ticker symbol and without a change in ticker symbol, “Gold” name addition and deletion, and different reasons for name changes (e.g., merger and acquisition, change of structure, change of strategy, and better image). The thesis uses the standard event study methodology to perform abnormal return and trading volume analyses. In addition, regression analysis is employed to examine which type of a name change has the largest impact on cumulative abnormal returns. Sample stocks exhibit a significant positive abnormal return one-day prior to the approval day and one day after the adoption date. Around the approval date we observe significant abnormal returns for stocks with a structural name change. On the day after the adoption date we document abnormal returns for stocks with major, minor, structural, pure, focused, and ticker symbol name changes. If a merger or acquisition is the reason for a name change, companies tend to experience a significant positive abnormal return one-day before the approval date and on the adoption date. If a change of structure is the reason for a name change, companies exhibit a significant positive abnormal return on the approval date and a significant negative abnormal return on the adoption date. In case of a change of strategy as the reason for a name change, companies show a significant negative abnormal return around the approval date and a significant positive abnormal return around the adoption date.
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Abstract Mixed Martial Arts (MMA) and the Ultimate Fighting Championship (UFC) founded in 1993 have been under scrutiny for the past two decades. Unlike boxing, the ethical status of MMA and whether it is morally defensible have rarely been analyzed in the academic literature. I argue that MMA requires such an analysis because it is inherently violent. The purpose of this study was to examine elite-level MMA by referring to the ethical concepts of autonomy, paternalism and the Harm Principle. Findings from interviews with MMA athletes as well as my personal experience of MMA were presented to establish a deeper understanding of the sport and what it means to train and compete in a sport defined as violent. The conceptual analysis and findings of MMA athletes' experiences in this investigation resulted in the conclusion that MMA is ethically defensible. Additional findings, implications and recommendations for further research were also discussed.
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Les histones sont des protéines nucléaires hautement conservées chez les cellules des eucaryotes. Elles permettent d’organiser et de compacter l’ADN sous la forme de nucléosomes, ceux-ci representant les sous unités de base de la chromatine. Les histones peuvent être modifiées par de nombreuses modifications post-traductionnelles (PTMs) telles que l’acétylation, la méthylation et la phosphorylation. Ces modifications jouent un rôle essentiel dans la réplication de l’ADN, la transcription et l’assemblage de la chromatine. L’abondance de ces modifications peut varier de facon significative lors du developpement des maladies incluant plusieurs types de cancer. Par exemple, la perte totale de la triméthylation sur H4K20 ainsi que l’acétylation sur H4K16 sont des marqueurs tumoraux spécifiques a certains types de cancer chez l’humain. Par conséquent, l’étude de ces modifications et des événements determinant la dynamique des leurs changements d’abondance sont des atouts importants pour mieux comprendre les fonctions cellulaires et moléculaires lors du développement de la maladie. De manière générale, les modifications des histones sont étudiées par des approches biochimiques telles que les immuno-buvardage de type Western ou les méthodes d’immunoprécipitation de la chromatine (ChIP). Cependant, ces approches présentent plusieurs inconvénients telles que le manque de spécificité ou la disponibilité des anticorps, leur coût ou encore la difficulté de les produire et de les valider. Au cours des dernières décennies, la spectrométrie de masse (MS) s’est avérée être une méthode performante pour la caractérisation et la quantification des modifications d’histones. La MS offre de nombreux avantages par rapport aux techniques traditionnelles. Entre autre, elle permet d’effectuer des analyses reproductibles, spécifiques et facilite l’etude d’un large spectre de PTMs en une seule analyse. Dans cette thèse, nous présenterons le développement et l’application de nouveaux outils analytiques pour l’identification et à la quantification des PTMs modifiant les histones. Dans un premier temps, une méthode a été développée pour mesurer les changements d’acétylation spécifiques à certains sites des histones. Cette méthode combine l’analyse des histones intactes et les méthodes de séquençage peptidique afin de déterminer les changements d’acétylation suite à la réaction in vitro par l’histone acétyltransférase (HAT) de levure Rtt109 en présence de ses chaperonnes (Asf1 ou Vps75). Dans un second temps, nous avons développé une méthode d’analyse des peptides isomériques des histones. Cette méthode combine la LC-MS/MS à haute résolution et un nouvel outil informatique appelé Iso-PeptidAce qui permet de déconvoluer les spectres mixtes de peptides isomériques. Nous avons évalué Iso-PeptidAce avec un mélange de peptides synthétiques isomériques. Nous avons également validé les performances de cette approche avec des histones isolées de cellules humaines érythroleucémiques (K562) traitées avec des inhibiteurs d’histones désacétylases (HDACi) utilisés en clinique, et des histones de Saccharomyces cerevisiae liées au facteur d’assemblage de la chromatine (CAF-1) purifiées par chromatographie d’affinité. Enfin, en utilisant la méthode présentée précédemment, nous avons fait une analyse approfondie de la spécificité de plusieurs HATs et HDACs chez Schizosaccharomyces pombe. Nous avons donc déterminé les niveaux d’acétylation d’histones purifiées à partir de cellules contrôles ou de souches mutantes auxquelles il manque une HAT ou HDAC. Notre analyse nous a permis de valider plusieurs cibles connues des HATs et HDACs et d’en identifier de nouvelles. Nos données ont également permis de définir le rôle des différentes HATs et HDACs dans le maintien de l’équilibre d’acétylation des histones. Dans l’ensemble, nous anticipons que les méthodes décrites dans cette thèse permettront de résoudre certains défis rencontrés dans l’étude de la chromatine. De plus, ces données apportent de nouvelles connaissances pour l’élaboration d’études génétiques et biochimiques utilisant S. pombe.
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The thesis deals with some of the non-linear Gaussian and non-Gaussian time models and mainly concentrated in studying the properties and application of a first order autoregressive process with Cauchy marginal distribution. In this thesis some of the non-linear Gaussian and non-Gaussian time series models and mainly concentrated in studying the properties and application of a order autoregressive process with Cauchy marginal distribution. Time series relating to prices, consumptions, money in circulation, bank deposits and bank clearing, sales and profit in a departmental store, national income and foreign exchange reserves, prices and dividend of shares in a stock exchange etc. are examples of economic and business time series. The thesis discuses the application of a threshold autoregressive(TAR) model, try to fit this model to a time series data. Another important non-linear model is the ARCH model, and the third model is the TARCH model. The main objective here is to identify an appropriate model to a given set of data. The data considered are the daily coconut oil prices for a period of three years. Since it is a price data the consecutive prices may not be independent and hence a time series based model is more appropriate. In this study the properties like ergodicity, mixing property and time reversibility and also various estimation procedures used to estimate the unknown parameters of the process.
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This thesis is devoted to the study of some stochastic models in inventories. An inventory system is a facility at which items of materials are stocked. In order to promote smooth and efficient running of business, and to provide adequate service to the customers, an inventory materials is essential for any enterprise. When uncertainty is present, inventories are used as a protection against risk of stock out. It is advantageous to procure the item before it is needed at a lower marginal cost. Again, by bulk purchasing, the advantage of price discounts can be availed. All these contribute to the formation of inventory. Maintaining inventories is a major expenditure for any organization. For each inventory, the fundamental question is how much new stock should be ordered and when should the orders are replaced. In the present study, considered several models for single and two commodity stochastic inventory problems. The thesis discusses two models. In the first model, examined the case in which the time elapsed between two consecutive demand points are independent and identically distributed with common distribution function F(.) with mean (assumed finite) and in which demand magnitude depends only on the time elapsed since the previous demand epoch. The time between disasters has an exponential distribution with parameter . In Model II, the inter arrival time of disasters have general distribution (F.) with mean ( ) and the quantity destructed depends on the time elapsed between disasters. Demands form compound poison processes with inter arrival times of demands having mean 1/. It deals with linearly correlated bulk demand two
Commodity inventory problem, where each arrival demands a random number of items of each commodity C1 and C2, the maximum quantity demanded being a (< S1) and b(
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Poor cold flow properties of vegetable oils are a major problem preventing the usage of many abundantly available vegetable oils as base stocks for industrial lubricants. The major objective of this research is to improve the cold flow properties of vegetable oils by various techniques like additive addition and different chemical modification processes. Conventional procedure for determining pour point is ASTM D97 method. ASTM D97 method is time consuming and reproducibility of pour point temperatures is poor between laboratories. Differential Scanning Calorimetry (DSC) is a fast, accurate and reproducible method to analyze the thermal activities during cooling/heating of oil. In this work coconut oil has been chosen as representative vegetable oil for the analysis and improvement cold flow properties since it is abundantly available in the tropics and has a very high pour point of 24 °C. DSC is used for the analysis of unmodified and modified vegetable oil. The modified oils (with acceptable pour points) were then subjected to different tests for the valuation of important lubricant properties such as viscometric, tribological (friction and wear properties), oxidative and corrosion properties.A commercial polymethacrylate based PPD was added in different percentages and the pour points were determined in each case. Styrenated phenol(SP) was added in different concentration to coconut oil and each solution was subjected to ASTM D97 test and analysis by DSC. Refined coconut oil and other oils like castor oil, sunflower oil and keranja oil were mixed in different proportions and interesterification procedure was carried out. Interesterification of coconut oil with other vegetable oils was not found to be effective in lowering the pour point of coconut oil as the reduction attained was only to the extent of 2 to 3 °C.Chemical modification by acid catalysed condensation reaction with coconut oil castor oil mixture resulted in significant reduction of pour point (from 24 ºC to -3 ºC). Instead of using triacylglycerols, when their fatty acid derivatives (lauric acid- the major fatty acid content of coconut oil and oleic acid- the major fatty acid constituents of monoand poly- unsaturated vegetable oils like olive oil, sunflower oil etc.) were used for the synthesis , the pour point could be brought down to -42 ºC. FTIR and NMR spectroscopy confirmed the ester structure of the product which is fundamental to the biodegradability of vegetable oils. The tribological performance of the synthesised product with a suitable AW/EP additive was comparable to the commercial SAE20W30 oil. The viscometric properties (viscosity and viscosity index) were also (with out additives) comparable to commercial lubricants. The TGA experiment confirmed the better oxidative performance of the product compared to vegetable oils. The sample passed corrosion test as per ASTM D130 method.
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The aim of catalysis research is to apply the catalyst successfully in economically important reactions in an environmentally friendly way. The present work focuses on the modification of structural and surface properties of ceria and ceria-zirconia catalysts by the incorporation of transition metals. The applications of these catalysts in industrially important reactions like ethylbenzene oxidation, alkylation of aromatics are also investigated.Sol-gel method is effective for the preparation of transition metal modified ceria and ceria-zirconia mixed oxide since it produces catalyst with highly dispersed incorporated metal. Unlike that of impregnation method plugging of pores is not prominent for sol-gel derived catalyst materials. This prevents loss of surface area on metal modification as evident for BET surface area measurements.The powder X-ray diffraction analysis confirms the cubic structure of transition metal modified ceria and ceria-zirconia catalysts. The thermal stability is evident from TGA/DTA analysis. DR UV-vis spectra provide information on the coordination environment of the incorporated metal. EPR analysis ofCr, Mn and Cu modified ceria and a ceria-zirconia catalyst reveals the presence of different oxidation states of incorporated metal.Temperature programmed desorption of ammonia and thermogravimetric desorption of 2,6-dimethyl pyridine confirms the enhancement of acidity on metal incorporation. High a-methyl styrene selectivity in cumene cracking reaction implies the presence of comparatively more number of Lewis acid sites with some amount of Bronsted acid sites. The formation of cyclohexanone during cyclohexanol decomposition confirms the presence of basic sites on the catalyst surface.Mn and Cr modified catalysts show better activity towards ethylbenzene oxidation. A redox mechanism through oxometal pathway is suggested.All the catalysts were found to be active towards benzylation of toluene and a-xylene. The selectivity towards monoalkylated products remains almost 100%. The catalytic activity is correlated with the Lewis acidity of the prepared systems.The activity of the catalysts towards methylation of phenols depends on the strength acid sites as well as the redox properties of the catalysts. A strong dependence of methylation activity on the total acidity is illustrated.
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Department of Applied Economics,Cochin University of Science and Technology
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Mn1-xZnxFe2O4 nanoparticles (x=0-1) were synthesized by wet chemical co-precipitation techniques. X-ray diffraction, transmission electron microscopy and high-resolution transmission electron microscopy were effectively utilized to investigate the different structural parameters. The elemental analysis was conducted using energy-dispersive spectrum and inductively coupled plasma analysis. The magnetic properties such as magnetization and coercivity were measured using vibrating sample magnetometer. The observed magnetization values of the nanoparticles were found to be lower compared to the bulk counterpart. The magnetization showed a gradual decrease with zinc substitution except for a small increase from x=0.2 to 0.3. The Curie temperature was found to be enhanced in the case of ferrites in the nanoregime. The variation in lattice constant, reduced magnetization values, variation of magnetization with zinc substitution, the presence of a net magnetic moment for the zinc ferrite and the enhancement in Curie temperature in Mn1-xZnxFe2O4 all provide evidence to the existence of a metastable cation distribution together with possible surface effects at the nanoregime.