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Äh! Vadå nervös? Kör nu bara! : En studie om hur lärare och elever kan arbeta i gymnasieskolan för att lära sig hantera rampfeberSparén, Jennie, Ryefalk, Rasmus January 2013 (has links)
The purpose of our study is to find out how teachers can help their students to learn how to managestage fright. By interviewing high school teachers and high school students and also observe one oftheir classes, we wanted to find out how they think about the causes of stage fright and what youcan do to relieve it. We also wanted to find out how teachers are working to teach students how todeal with stage fright, and how they think that you also could work. As a teacher of music, among other things, the task is to assess and rate the students performancesin music. Several components are based on the students' courage to play on his or her instrument infront of other people. Those who suffer from stage fright find this in many cases hard, which bothinhibit the student's development and hampers the assessment for the teacher. It is assumed, however, implicit in the curriculum of music that stage fright does not exist or that students have thetools to manage it. We want our work to provide an input into how teachers in high school can work with stage frightwith their students and we believe that teachers in other subjects also can use this. There is some research on how to deal with stage fright as a musician, but a lot comes from thesport which for a long time has studied how to perform best under pressure. The results of our studyshow that stage fright can be caused by several things, and that there are also several ways to learn how to manage it. For example, to be well prepared and gain greater self-awareness. Much is basedon strengthening self-esteem and make sure the teacher sees each student's needs. But theinterviewed teachers also feel that they lack skills and education in the area, and they base their thoughts only on their own empirical data.
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Reduction and Speciation of Monoglycerides to Produce High Quality BiodieselRapaka, Srikanth 26 July 2012 (has links)
Biodiesel is rapidly growing as a fuel of interest due to the various advantages it has over conventional diesel fuel. While the pros – non-toxic, biodegradable, low green house gas emissions seem advantageous, the major issue that plagues the use of biodiesel is its cold weather operability. Biodiesel can present challenges in cold-weather operation, because certain of its constituent compounds can form precipitates in the fuel. These precipitates can cause undesired effects like plugging of fuel filters and deposits. This issue has been attributed to the presence of impurities (mostly saturated monoglycerides, di-glycerides, soap etc) in biodiesel and has been discussed in the literature. There is a move by users and standards associations to implement more stringent norms and quality control to avoid problems in the widespread use of biodiesel. This study involves ways to reduce MG’s in biodiesel by mitigating to a greater extent the possibility of side reactions (formation of soap). The effect of selective transesterification of oil as a function of alcohol, temperature and catalyst concentration was also studied. Although saturated MG’s with high melting points are a greater source of deposits, it can be hypothesized that the polymorphic nature of unsaturated Monoglycerides could also be contributing to cold flow issues. It is hence vital to make sure the biodiesel is free from all forms of monoglycerides. It was also seen that there is very little specificity of selection of fatty acid types in the transesterification reaction and that the amount and type of MGs present in the biodiesel is reflected by the relative amount of fatty acids types present in the oil. In biodiesel derived from Canola oil, a preponderance of monoolein was found for all runs. The initial runs carried out as a two stage process using the membrane followed by batch reactor gave very low MG concentrations, well below ASTM standards.
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Antihypertrophic effect of hemin in deoxycorticosterone acetate-salt-induced hypertensive rat modelJadhav, Ashok B. 14 January 2009
The application of the synthetic mineralocorticoid, deoxycorticosterone acetate (DOCA)-salt, to unilaterally nephrectomised rats induces severe hypertension due to volume-overload, and mimics human primary aldosteronism. Importantly, DOCA-salt hypertension is characterized by severe cardiac and renal lesions triggered by nuclear factor kappa B (NF-kappaB), activating protein (AP-1), and transforming growth factor beta1 (TGF-beta1) leading to end-stage organ damage. Although DOCA-salt hypertension is a low renin model, local production of angiotensin-II and aldosterone in cardiac and renal tissues stimulate TGF-beta1, fibronectin and collagen-1 causing fibrosis and hypertrophy. Since TGF-beta1 gene promoter contains binding sites for NF-kappaB and AP-1, cross-talk between TGF-beta1, NF-kappaBnand AP-1 can be envisaged. Accordingly, the activation of TGF-beta1, fibronectin, collagen, NF-kappaB and AP-1 may constitute a potent destructive force in hypertension.<p>
Emerging evidence indicates that upregulation of the heme oxygenase (HO) system is cytoprotective with antioxidant, antihypertensive and antihypertrophic effects. Interestingly, the promoter region of HO-1 gene harbors consensus-binding sites for NF-kappaB and AP-1; therefore, the HO system may regulate these transcription factors to counteract tissue insults. However, the multifaceted interactions between the HO system, NF-kappaB, AP-1, TGF-beta1, fibronectin and collagen in mineralocorticoid-induced end-stage-organ damage have not been fully characterized. Similarly, the effect of the HO system on tissue angiotensin-II and aldosterone levels in mineralocorticoid-induced hypertension remains unclear. Therefore, the present study was designed to investigate the antihypertrophic effect of the HO system in cardiac and renal tissue of DOCA-salt hypertensive rats.
In this study, the HO inducer, hemin, lowered blood pressure and attenuated cardiac/renal hypertrophy, whereas the HO inhibitor, chromium mesoporphyrin (CrMP), nullified the effects of hemin and exacerbated cardiac/renal injury the DOCA-salt hypertensive rats. The protective effect of hemin was associated with increased HO-1, HO activity, cyclic guanosine monophosphate (cGMP), superoxide dismutase activity, ferritin and the total antioxidant capacity in the cardiac and renal tissue. In contrast, angiotensin-II, aldosterone, 8-isoprostane, NF-kappaB and AP-1 were significantly downregulated. Furthermore, hemin therapy attenuated TGF-beta1 and extracellular matrix (ECM) proteins such as fibronectin and collagen, with corresponding reduction of cardiac histopathological lesions, including longitudinal/cross-sectional muscle fiber thickness, scarring, muscular hypertrophy, coronary arteriolar thickening and collagen deposition. Similarly, hemin attenuated structural lesions in the kidney such as glomerular hypertrophy, glomerular sclerosis, mononuclear cell infiltration, tubular cast formation, tubular dilation and renal arteriolar thickening with concomitant improvement of kidney function as evidenced by reduction of plasma creatinine, proteinuria, but enhanced creatinine clearance.<p>
Collectively, these results suggest that the HO system suppressed hypertension, cardiac and renal fibrosis, and hypertrophy in the DOCA-salt hypertensive rat by downregulating transcription factors such as NF-kappaB and AP-1, reducing ECM proteins such as fibronectin and collagen, decreasing local tissue production of angiotensin-II and aldosterone, and improved renal functional capacity.
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Improved Vacuum Frying Process for High Quality Sweet Potato ChipsRavli, Yagmur 1985- 14 March 2013 (has links)
Vacuum frying is a promising method for preserving the desired color, texture, and flavor of products with high sugar content. Since most vegetables and fruits degrade when processed with traditional frying, vacuum frying is an excellent alternative to high temperature processing. However, in vacuum frying the product should be pre-treated before frying to obtain a better texture.
The kinetics of oil absorption and oil distribution in sweet potato chips (total, internal, and surface oil content) was studied so that effectiveness of the de-oiling system could be established. An analysis of product quality attributes (PQA) such as moisture content, oil content, microstructure, diameter shrinkage, and thickness expansion, as well as, color, texture, bulk density, true density, and porosity of chips fried at different temperatures (120, 130, and 140°C) was performed to evaluate the effect of process temperature on the product.
The final oil content of the sweet potato chips was 0.178±0.007, 0.178±0.011, and 0.172±0.002 g/g solid for frying temperatures of 120, 130, and 140ºC, respectively. These values were lower (~60% less) than those found in traditionally fried sweet potato chip, which indicates that the de-oiling mechanism is crucial in vacuum frying processing.
It was found that the rate of change in PQAs is greatly affected by temperature; however, the final values of bulk density, true density, porosity, diameter shrinkage, and thickness expansion were not affected by temperature. The texture of the samples was affected by temperature, with the chips fried at 140 degrees C being crispier. In terms of color, the L* and color b* values decreased as temperature increased. While color a* was not affected by temperature.
In this study, a two-stage frying process was also evaluated to improve the flavor and texture of sweet potato chips. First, a basket filled with the sweet potato slices was submerged into the oil under atmospheric conditions. As soon as the potato slices were partially cooked (1 min), the pressure was lowered to 1.33 kPa (vacuum frying stage) and the product fried for 2 more min. The products were fried at 130 degrees C for different interval of times. Starch gelatinization, texture, moisture content, and oil content were evaluated at each time interval. Sensory analysis was accomplished by using a consumer panel with 50 members. The samples were compared with the on-stage frying and atmospheric frying processes.
The two-stage fried chips had better appearance and texture compared to the ones that were only fried under vacuum or atmospheric conditions. The samples were lighter and more yellow than the chips fried under the single-stage process. In vacuum frying, the temperature of the chips does not reach the gelatinization temperature until most of the water is evaporated. Therefore, there is not sufficient moisture content in the product for gelatinization to occur completely. As a result, the product has a glassy texture. In the two stage frying, the atmospheric frying prior to vacuum frying helps the starch to gelatinize thus producing a better product in terms of texture, oil content, and flavor. The atmospheric fried samples were darker in color and had a scorch taste. The degree of starch gelatinization was 21% higher for the two-stage fried samples than the single-stage fried ones.
The application of the dual stage enhances the quality of sweet potato chips, improves consumer satisfaction, and reduces the need for space, cost, and any other needs of blanching pre-treatment to the sweet potato manufacturers.
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オープンアクセスジャーナルの現状三根, 慎二, Mine, Shinji 08 1900 (has links)
No description available.
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Reasoning About Multi-stage ProgramsInoue, Jun 24 July 2013 (has links)
Multi-stage programming (MSP) is a style of writing program
generators---programs which generate programs---supported by special
annotations that direct construction, combination, and execution of
object programs. Various researchers have shown MSP to be effective
in writing efficient programs without sacrificing genericity.
However, correctness proofs of such programs have so far received
limited attention, and approaches and challenges for that task have
been largely unexplored. In this thesis, I establish formal
equational properties of the multi-stage lambda calculus and related
proof techniques, as well as results that delineate the intricacies
of multi-stage languages that one must be aware of.
In particular, I settle three basic questions that naturally arise
when verifying multi-stage functional programs. Firstly, can adding
staging MSP to a language compromise the interchangeability of terms
that held in the original language? Unfortunately it can, and more
care is needed to reason about terms with free variables. Secondly,
staging annotations, as the term ``annotations'' suggests, are often
thought to be orthogonal to the behavior of a program, but when is
this formally guaranteed to be the case? I give termination
conditions that characterize when this guarantee holds. Finally, do
multi-stage languages satisfy extensional facts, for example that
functions agreeing on all arguments are equivalent? I develop a
sound and complete notion of applicative bisimulation, which can
establish not only extensionality but, in principle, any other valid
program equivalence as well. These results improve our general
understanding of staging and enable us to prove the correctness of
complicated multi-stage programs.
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High Efficiency Two-Stage GaN Power Amplifier with Improved LinearityKhan, Amreen January 2013 (has links)
The trade-off between linearity and efficiency is the key limiting factor to wideband power amplifier design. Current wireless research focuses much of its effort on building power amplifiers with the two aforementioned criteria going hand in hand to build an optimal design.
This thesis investigates the sources of nonlinearity associated with GaN high electron mobility transistors (HEMT), and their subsequent effects on the linearity metrics of the power amplifier. The investigation began with an analysis of the sources of nonlinearity, and then a design-based approach to mitigate those sources of nonlinearity was developed. This design approach was compared with existing trends in power amplifier design. The device technology used in the design was CREE GaN HEMT (45W and 6W).
In this report, a systematic approach to designing a two stage power amplifier is discussed, and analyzed for design of linear and highly efficient power amplifiers for base stations. The designed power amplifier consists of two stages: a driver stage and a power stage. The driver stage aimed to linearize the power stage by using circuit analysis and transistor properties along with providing the necessary gain. The power stage was built to complement the driver stage and to achieve high efficiency for the power amplifier. An inter-stage matching network placed between the two stages allowed for the required matching of impedances; transmission lines in the bias feed controlled the harmonic impedances for optimal performance without disrupting performance at fundamental frequencies. This approach effectively improved, and maintained, high efficiency over 200MHz of bandwidth.
The design approach was simulated and fabricated in order to test the feasibility of linear power amplifier operation with the use of digital pre-distortion (DPD). The fabricated prototype achieved about 70% peak efficiency over the bandwidth and maintained linearity above 40dBc adjacent channel leakage ratio (ACLR) and below 3% error vector magnitude (EVM). The measurement results indicated that the need for DPD was eliminated when the power amplifier was operating in back-off at the center frequency (800MHz). This thesis compares the prototyped design with existing multistage designs which use linear drivers. The report provides conclusions derive from measurement results and bandwidth limitations faced throughout the course of the design. Lastly, potential research directions, which may allow researchers to overcome the limitations of this design, are discussed.
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Les jeunes adultes québécois dans la rencontre de l'autre lors d'un stage d'initiation à la coopération internationaleChoquette, Dominique January 2008 (has links) (PDF)
L'engouement pour les stages de coopération internationale est très prégnant auprès des jeunes adultes québécois. De nombreux stages sont par ailleurs offerts par des organismes de coopération internationale dans certains pays en développement. Dans cette dynamique se pose alors la question des rapports à l'Autre et la façon dont les stagiaires impliqués dans une démarche de stage vivent et se représentent la rencontre avec l'Autre. Plus globalement, cela met en exergue les rapports d'identité et d'altérité en présence dans le stage de coopération internationale. Cette recherche s'est déroulée auprès de 10 stagiaires impliqués dans un stage d'initiation à la coopération internationale en Afrique provenant de deux organismes de coopération internationale. Des rencontres avec les stagiaires avant et après leur stage en Afrique, et avec les responsables de stage dans les organismes ont eu lieu. Ces rencontres ont permis d'identifier six constats et de formuler huit recommandations quant à l'amélioration de la mise en oeuvre des stages pour favoriser une meilleure rencontre de l'Autre. Les constats sont: 1) le stage est perçu comme un voyage d'épreuves initiatiques pour découvrir son identité; 2) l'Autre est perçu en autoréférence avec le Soi et permet d'attester de sa présence au monde; 3) la rencontre de l'Autre provoque une exotisation ou une idéalisation de l'Autre; 4) le stage se pose en discontinuité du parcours de vie des stagiaires et les apprentissages sont surtout liés à la découverte de soi; 5) l'intégration durant le stage est conçue comme la participation à un projet et aux pratiques de la vie quotidienne; et 6) le retour au pays se vit sur le mode de la compensation et le désir de combler un certain vide ressenti au retour. Les recommandations s'inscrivent dans la perspective d'un recentrement du stage autour du projet réalisé à l'étranger pour favoriser une meilleure implication des stagiaires durant leur séjour. Elles concernent: 1) l'amélioration des critères de sélection des stagiaires; 2) la clarification du fonctionnement du projet de stage et la mise en place de journées éducatives; 3) la mise en place d'ateliers de formation sur la langue, la connaissance de soi et de sa culture d'origine, la culture d'accueil, la meilleure préparation du retour de stage et celle des familles d'accueil; 4) la relativisation de l'importance du groupe de stagiaires lors de la réalisation du séjour à l'étranger; 5) le meilleur soutien de la part de la personne accompagnatrice comme pivot de l'intégration des stagiaires; 6) le meilleur encadrement favorisant la latitude pour l'implication des stagiaires dans le projet d'éducation du public; 7) le développement d'outils d'information pour l'entourage des stagiaires; et 8) l'accent sur des ateliers d'introspection de soi et d'exploration de pistes d'implication durant la rencontre de bilan de stage. ______________________________________________________________________________ MOTS-CLÉS DE L’AUTEUR : Stage, Identité, Altérité, Coopération internationale, Organisme de coopération internationale, Jeunes adultes québécois.
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DIGITAL GAIN ERROR CORRECTION TECHNIQUE FOR 8-BIT PIPELINE ADCjaveed, khalid January 2010 (has links)
An analog-to-digital converter (ADC) is a link between the analog and digital domains and plays a vital role in modern mixed signal processing systems. There are several architectures, for example flash ADCs, pipeline ADCs, sigma delta ADCs,successive approximation (SAR) ADCs and time interleaved ADCs. Among the various architectures, the pipeline ADC offers a favorable trade-off between speed,power consumption, resolution, and design effort. The commonly used applications of pipeline ADCs include high quality video systems, radio base stations,Ethernet, cable modems and high performance digital communication systems.Unfortunately, static errors like comparators offset errors, capacitors mismatch errors and gain errors degrade the performance of the pipeline ADC. Hence, there is need for accuracy enhancement techniques. The conventional way to overcome these mentioned errors is to calibrate the pipeline ADC after fabrication, the so-called post fabrication calibration techniques. But environmental changes like temperature and device aging necessitates the recalibration after regular intervals of time, resulting in a loss of time and money. A lot of effort can be saved if the digital outputs of the pipeline ADC can be used for the estimation and correctionof these errors, further classified as foreground and background techniques. In this thesis work, an algorithm is proposed that can estimate 10% inter stage gain errors in pipeline ADC without any need for a special calibration signal. The efficiency of the proposed algorithm is investigated on an 8-bit pipeline ADC architecture.The first seven stages are implemented using the 1.5-bit/stage architecture whilethe last stage is a one-bit flash ADC. The ADC and error correction algorithms simulated in Matlab and the signal to noise and distortion ratio (SNDR) is calculated to evaluate its efficiency.
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Antihypertrophic effect of hemin in deoxycorticosterone acetate-salt-induced hypertensive rat modelJadhav, Ashok B. 14 January 2009 (has links)
The application of the synthetic mineralocorticoid, deoxycorticosterone acetate (DOCA)-salt, to unilaterally nephrectomised rats induces severe hypertension due to volume-overload, and mimics human primary aldosteronism. Importantly, DOCA-salt hypertension is characterized by severe cardiac and renal lesions triggered by nuclear factor kappa B (NF-kappaB), activating protein (AP-1), and transforming growth factor beta1 (TGF-beta1) leading to end-stage organ damage. Although DOCA-salt hypertension is a low renin model, local production of angiotensin-II and aldosterone in cardiac and renal tissues stimulate TGF-beta1, fibronectin and collagen-1 causing fibrosis and hypertrophy. Since TGF-beta1 gene promoter contains binding sites for NF-kappaB and AP-1, cross-talk between TGF-beta1, NF-kappaBnand AP-1 can be envisaged. Accordingly, the activation of TGF-beta1, fibronectin, collagen, NF-kappaB and AP-1 may constitute a potent destructive force in hypertension.<p>
Emerging evidence indicates that upregulation of the heme oxygenase (HO) system is cytoprotective with antioxidant, antihypertensive and antihypertrophic effects. Interestingly, the promoter region of HO-1 gene harbors consensus-binding sites for NF-kappaB and AP-1; therefore, the HO system may regulate these transcription factors to counteract tissue insults. However, the multifaceted interactions between the HO system, NF-kappaB, AP-1, TGF-beta1, fibronectin and collagen in mineralocorticoid-induced end-stage-organ damage have not been fully characterized. Similarly, the effect of the HO system on tissue angiotensin-II and aldosterone levels in mineralocorticoid-induced hypertension remains unclear. Therefore, the present study was designed to investigate the antihypertrophic effect of the HO system in cardiac and renal tissue of DOCA-salt hypertensive rats.
In this study, the HO inducer, hemin, lowered blood pressure and attenuated cardiac/renal hypertrophy, whereas the HO inhibitor, chromium mesoporphyrin (CrMP), nullified the effects of hemin and exacerbated cardiac/renal injury the DOCA-salt hypertensive rats. The protective effect of hemin was associated with increased HO-1, HO activity, cyclic guanosine monophosphate (cGMP), superoxide dismutase activity, ferritin and the total antioxidant capacity in the cardiac and renal tissue. In contrast, angiotensin-II, aldosterone, 8-isoprostane, NF-kappaB and AP-1 were significantly downregulated. Furthermore, hemin therapy attenuated TGF-beta1 and extracellular matrix (ECM) proteins such as fibronectin and collagen, with corresponding reduction of cardiac histopathological lesions, including longitudinal/cross-sectional muscle fiber thickness, scarring, muscular hypertrophy, coronary arteriolar thickening and collagen deposition. Similarly, hemin attenuated structural lesions in the kidney such as glomerular hypertrophy, glomerular sclerosis, mononuclear cell infiltration, tubular cast formation, tubular dilation and renal arteriolar thickening with concomitant improvement of kidney function as evidenced by reduction of plasma creatinine, proteinuria, but enhanced creatinine clearance.<p>
Collectively, these results suggest that the HO system suppressed hypertension, cardiac and renal fibrosis, and hypertrophy in the DOCA-salt hypertensive rat by downregulating transcription factors such as NF-kappaB and AP-1, reducing ECM proteins such as fibronectin and collagen, decreasing local tissue production of angiotensin-II and aldosterone, and improved renal functional capacity.
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