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Fluctuations and Oscillations in Cell MembranesHändel, Chris 22 February 2016 (has links)
Zellmembranen sind hochspezialisierte Mehrkomponentenlegierungen, welche sowohl die
Zelle selbst als auch ihre Organellen umgeben. Sie spielen eine entscheidende Rolle bei
vielen biologisch relevanten Prozessen wie die Signaltransduktion und die Zellbewegung.
Aus diesem Grund ist eine genaue Charakterisierung ihrer Eigenschaften der Schlüssel
zum Verständnis der Bausteine des Lebens sowie ihrer Erkrankungen. Besonders Krebs
steht im engen Zusammenhang mit Veränderungen der biomechanischen Eigenschaften
vom Gewebe, Zellen und ihren Organellen. Während Veränderungen des Zytoskeletts
von Krebszellen im Fokus vieler Biophysiker stehen, ist die Bedeutung der Biomechanik
von Zellmembran weitgehend unklar. Zellmembranen faszinieren Wissenschaftler jedoch
nicht nur wegen ihrer biomechanischen Eigenschaften. Sie sind auch Beispiele für eine
selbstorganisierte und heterogene Landschaft, in der Prozesse fernab des Gleichgewichtes,
wie z.B. räumliche und zeitliche Musterbildungen, auftreten. Die vorgelegte Dissertation
untersucht erstmals umfassend die zentrale Rolle der Zellmembran und ihrer molekularen
Architektur für die Signalübertragung, die Biomechanik und die Zellmigration. Hierfür
werden einfache Modellmembranen aber auch komplexere Vesikel und ganze Zellen
mittels etablierter physikalischer Methoden analysiert. Diese reichen von Fourier-
Analysen zur Charakterisierung von thermisch angeregten Membranundulationen über
Massenspektrometrie und ‘Optical Stretcher’ Messungen von ganzen Zellen bis hin
zur Filmwaagentechnik. Des Weiteren wird ein Modellsystem vorgestellt, welches
sowohl einen experimentellen als auch einen mathematischen Zugang zum ‘ME-switch’
ermöglicht. Die vorgelegte Dissertation bietet neue Einblicke in wichtige Funktionen
von Zellmembranen und zeigt neue therapeutische Perspektiven in der Membran- und
Krebsforschung auf.:1 Introduction
2 Background
2.1 The Cell Membrane
2.1.1 Lipids in Cell Membranes
2.1.2 Membrane Proteins
2.1.3 An Overview on Membrane Models
2.1.4 Lipid Rafts
2.2 Model Membranes – An Experimental Access to Cell Membranes
2.2.1 Surface Tension and Thermodynamic Equilibrium
2.2.2 Langmuir Monolayer
2.2.3 The Polymorphism of Langmuir Monolayers
2.2.4 Membrane Vesicles
2.3 Biological Membranes as Semiflexible Shells
2.3.1 Elasticity of Soft Shells
2.3.2 Helfrichs Theory About Bending Deformations
2.3.3 Membrane Undulation
2.4 Membranes in Cell Signaling
2.4.1 Signal Transduction Fundamentals
2.4.2 Phosphoinositides
2.4.3 Phosphatidylinositol Signaling Pathway
2.4.4 The Myristoyl-Electrostatic Switch
2.5 Reaction-Diffusion Systems
2.5.1 Diffusion
2.5.2 Michaelis-Menten Kinetics
2.5.3 Reaction-Diffusion Systems
3 Methods, Materials and Theory
3.1 Optical Microscopy
3.1.1 Fluorescence Microscopy
3.1.2 Phase Contrast Microscopy
3.2 Cell Culture and GPMV Formation
3.2.1 Tumor Dissociation and Cell Culturing of Primary Cells
3.2.2 Cell Lines and Cell Culturing
3.2.3 Preparation of Giant Plasma Membrane Vesicles
3.3 Optical Stretcher
3.4 Fourier Analysis of Thermally Excited Membrane Fluctuations
3.4.1 The Quasi-Spherical Model – Membrane Fluctuations
3.4.2 Determination of the Bending Rigidity
3.5 Mass Spectrometry
3.5.1 MALDI-TOF Mass Spectrometry
3.5.2 ESI Mass Spectrometry
3.6 Migration, Invasion and Cell Death Assays
3.7 Langmuir-Blodgett Technique
3.7.1 Langmuir Troughs and Film Balances
3.7.2 Experimental Setup and Monolayer Preperation
3.7.3 Phospholipids, Dyes and Buffer Solutions
4 Fluctuations in Cell Membranes
4.1 Cell Membrane Softening in Human Breast and Cervical Cancer Cells
4.1.1 Bending Rigidity of Human Beast and Cervical Cell Membranes
4.1.2 MALDI-TOF Analysis of Lipid Composition
4.1.3 Summary and Discussion
4.2 Targeting of Membrane Rigidity – Implications on Migration
4.2.1 ESI Tandem Analysis of Lipid Composition
4.2.2 Biomechanical Behavior of Whole Cells and Membranes
4.2.3 Migration and Invasion Behavior
4.2.4 Summary and Discussion
5 Oscillations in Cell Membranes
5.1 Mimicking the ME-switch
5.1.1 DPPC/PIP2 monolayers at the presence of MARCKS
5.1.2 Lateral organization of PIP2 in DPPC/PIP2 monolayers
5.1.3 Translocation of MARCKS
5.1.4 Phosphorylation of MARCKS by PKC
5.1.5 Summary and Discussion
5.2 Dynamic Membrane Structure Induces Temporal Pattern Formation
5.2.1 Mechanism of the Oscillation
5.2.2 Modeling the ME-switch
5.2.3 Time Evolution
5.2.4 Phase Diagrams and Open Systems
5.2.5 Summary and Discussion
6 Conclusion and Outlook
Appendix
Bibliography
List of Figures
List of Abbreviations
Acknowledgement
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Validation of Mechanical Response Tissue Analysis by Three-Point Mechanical Bending of Artificial Human UlnasArnold, Patricia A. 03 June 2013 (has links)
No description available.
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Comparison of Cortical Porosity, Diameter, and Stiffness as Predictors of Ulna Bending StrengthHausfeld, Gabrielle Christine 30 April 2015 (has links)
No description available.
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Связь психологического благополучия и личностных особенностей в контексте понимания человека как открытой саморазвивающейся системы : магистерская диссертация / The relationship between psychological well-being and personal characteristics in the context of understanding a person as an open self-developing systemДолгошеина, А. А., Dolgosheina, A. A. January 2024 (has links)
Объектом исследования является психологическое благополучие студентов. Предметом исследования стала связь психологического благополучия студентов с личностными особенностями, которые являются показателями открытости психологической системы (ригидность, флексибильность, когнитивная закрытость, локус контроля). Магистерская диссертация состоит из введения, двух глав, заключения, списка литературы (103 источника) и приложения, включающего в себя сводную таблицу результатов корреляционного анализа. Объем магистерской диссертации 86 страниц, на которых размещены 2 рисунка и 9 таблиц. Во введении раскрывается актуальность проблемы исследования, разработанность проблематики, ставятся цель и задачи исследования, определяются объект и предмет исследования, формулируются гипотезы, указываются методики для проведения эмпирического исследования. Первая глава включает в себя обзор иностранной и отечественной литературы по теме психологического благополучия, ригидности, флексибильности, когнитивной закрытости и локуса контроля. Представлены разделы, посвященные исследованию подходов к пониманию термина «благополучие» и основных факторов психологического благополучия; понятия самореализации в рамках системного подхода; специфики континуума «ригидность – флексибильность», когнитивной закрытости и локуса контроля, как показателей открытости психологической системы человека. Выводы по первой главе представляют собой итоги по изучению теоретического материала. Вторая глава посвящена эмпирической части исследования. В ней представлено описание методов проведенного исследования и результатов, полученных по всем использованным методикам: опросник Шкала психологического благополучия К. Рифф, Томский опросник ригидности В. Залевского, Опросник когнитивной флексибильности J.Dennis, J. VanderWal, опросник Стремление к когнитивной закрытости D. Webster, A. Kruglanski, шкала Локуса контроля Дж. Роттера. Также в главе представлен корреляционный анализ результатов исследования. Выводы по главе 2 включают в себя основные результаты эмпирического исследования. В заключении в обобщенном виде изложены результаты теоретической и эмпирической частей работы, а также выводы по выдвинутым гипотезам. / The object of the study is the psychological well-being of students. The subject of the study was the relationship of students' psychological well-being with personal characteristics, which are indicators of the openness of the psychological system (rigidity, flexibility, cognitive closeness, locus of control). The master's thesis consists of an introduction, two chapters, a conclusion, a list of references (103 sources) and an appendix, which includes a summary table of the results of correlation analysis. The volume of the master's thesis is 86 pages, which contain 2 figures and 9 tables. The introduction reveals the relevance of the research problem, the elaboration of the problem, sets the purpose and objectives of the study, defines the object and subject of the study, formulates hypotheses, specifies methods for conducting empirical research. The first chapter includes a review of foreign and domestic literature on the topic of psychological well-being, rigidity, flexibility, cognitive closure and locus of control. The sections devoted to the study of approaches to understanding the term "well-being" and the main factors of psychological well–being; the concept of self-realization within the framework of a systematic approach; the specifics of the continuum "rigidity - flexibility", cognitive closeness and locus of control as indicators of the openness of the human psychological system are presented. The conclusions of the first chapter represent the results of the study of theoretical material. The second chapter is devoted to the empirical part of the study. It describes the methods of the study and the results obtained using all the methods used: K. Riff Scale of Psychological Well-being questionnaire, V. Zalevsky Tomsk Rigidity Questionnaire, J.Dennis, J. VanderWal Cognitive Flexibility Questionnaire, D. Webster, A. Kruglanski, J. Webster Locus Control scale. Rotter. The chapter also presents a correlation analysis of the results of the study. The conclusions of Chapter 2 include the main results of the empirical study. In conclusion, the results of the theoretical and empirical parts of the work, as well as conclusions on the hypotheses put forward, are summarized.
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Ocular biomechanics in glaucoma and space-related neuro-ocular syndrome : assessing ocular rigidity and pulsatile optic nerve deformation with video-optical coherence tomography.Masís-Solano, Marissé 04 1900 (has links)
La compréhension des propriétés biomécaniques de la tête du nerf optique (TNO) est cruciale pour la gestion de conditions telles que le glaucome et le Syndrome Neuro-Oculaire Lié à l'Espace (SNOE). Cette thèse propose d’utiliser l'imagerie par tomographie de cohérence optique vidéo à haute fréquence (V-OCT) traitée avec des algorithmes de traitement d'image existants pour évaluer quantitativement la déformation pulsatile de la TNO due aux cycles cardiaques. Cette méthode est utilisée afin d’investiguer deux phénomènes: la réponse biomécanique de la TNO dans les conditions terrestres; et la réponse du TNO dans l'environnement de microgravité de l'espace.
Le premier segment de cette thèse présente une nouvelle méthode non-invasive pour mesurer le déplacement pulsatile de la TNO via l'OCT vidéo (V-OCT), offrant des progrès significatifs dans la quantification des propriétés biomécaniques de l'œil in vivo. Une validation approfondie de cette technique, à la fois numérique et expérimentale, a confirmé la sensibilité de l'algorithme aux déformations induites, sa robustesse face à divers niveaux de bruit, et sa répétabilité. Deux groupes d’individus, sains et myopes, ont été évalués sous différentes conditions de contrainte physiologique. La déformation pulsatile des tissus de la TNO a été capturée quantitativement et représentée sous forme de cartes de déformation, montrant la sensibilité de la méthodologie aux déformations induites et la robustesse aux interférences de bruit élevé. Pour les sujets dont les yeux ont une longueur axiale de moins de 25mm, des différences notables de déformation pulsatile médiane ont émergé entre les positions primaires et en abduction de l'œil, avec une reproductibilité confirmée via des coefficients de corrélation intra-classe élevés.
Ayant validé la méthode, elle a donc a été appliquée à une cohorte de glaucomateux pour examiner l'impact de la réduction de la pression intraoculaire (PIO) sur le déplacement pulsatile de la TNO. Chez les patients atteints de glaucome primaire à angle ouvert (GPAO), en particulier ceux sans myopie axiale, les interventions abaissant la PIO ont conduit à une réduction significative de la pulsation de la TNO. Cependant, les patients glaucomateux myopes n'ont affiché aucun changement substantiel, suggérant une relation nuancée entre la modulation de la PIO et la biomécanique de la TNO. Une étude de cohorte n’a révélé aucune différence marquée dans la pulsation de la TNO à travers divers degrés de gravité du glaucome. Pourtant, la déformation pulsatile a été corrélée à l'épaisseur de la couche de fibres nerveuses rétiniennes et à des mesures hémodynamiques spécifiques, soulignant les interconnexions complexes entre la biomécanique et l'hémodynamique oculaires.
La dernière partie de cette thèse aborde les modifications de la rigidité oculaire chez les astronautes avant et après des vols spatiaux prolongés. En analysant les données de 26 yeux de 13 astronautes, la recherche a démontré des réductions significatives de la rigidité oculaire, de la pression intraoculaire et de l'amplitude du pouls oculaire après la mission. Ces découvertes explorent des effets précédemment inconnus de la microgravité sur les propriétés mécaniques de l'œil, améliorant notre compréhension du SNOE.
Cette étude, tout en approfondissant notre compréhension des complexités biomécaniques et hémodynamiques de la TNO, démontre le potentiel du V-OCT comme outil pour le diagnostic et le suivi des conditions du nerf optique. Les techniques et les perspectives acquises ici posent également les bases pour de futures explorations prometteuses à la fois pour les patients atteints de glaucome et pour les astronautes. / The eye is a semi-rigid sphere with complex biomechanical properties. Chronic disease or stress like space flight can interfere with these properties, leading to vision loss. Noninvasive measurements of the biomechanical properties of the optic nerve head (ONH) could provide better tracking and management of conditions such as glaucoma and Space-Related Neuro-Ocular Syndrome (SANS). This thesis proposes to use high-frequency optical coherence tomography video imaging (V-OCT) with existing image processing algorithms to quantitatively evaluate the pulsatile displacement of the ONH due to cardiac cycles. This methodology is applied across two streams of research: examining the ocular biomechanical response of the ONH under terrestrial conditions; and the ONH deformation in the microgravity environment of space.
The first section of this thesis introduces a non-invasive method to measure ONH pulsatile displacement via video-based OCT (V-OCT), quantifying biomechanical eye properties in vivo. A thorough validation of this technique, both numerically and experimentally, confirmed the algorithm’s sensitivity to induced deformation, robustness against various noise levels, and repeatability. Two groups, healthy and myopic individuals, underwent assessment under different physiological strain conditions. Pulsatile ONH tissue deformation was quantitatively captured and represented as deformation maps. For those subjects with eyes with an axial length of less than 25mm, notable median pulsatile displacement differences were found between primary and abducted eye positions. Reproducibility was confirmed via high intraclass correlation coefficients.
Building on this foundation, the method was applied to a cohort of glaucoma patients to examine the impact of IOP reduction on ONH pulsatile displacement. In primary open-angle glaucoma (POAG) patients, particularly those without axial myopia, IOP-lowering interventions significantly reduced ONH pulsation. However, myopic glaucoma patients displayed no substantial changes, suggesting that myopic status moderates the relationship between IOP modulation and ONH biomechanics. This pilot study was expanded to a larger cross-sectional cohort study (N=176), revealing a decrease in ONH pulsatile displacement in people with early and moderate glaucoma compared to controls. . In addition, pulsatile displacement correlated with retinal nerve fiber layer thickness and specific hemodynamic measures, showing that ocular biomechanics and hemodynamics are closely linked.
The last section of the thesis investigates ocular rigidity alterations in astronauts before and after extended space flights. Analyzing data from 26 eyes of 13 astronauts, significant reductions in ocular rigidity were observed; similarly, intraocular pressure and ocular pulse amplitude were reduced post-mission. These findings reveal previously undocumented microgravity effects on the eye's mechanical properties, improving our comprehension of SANS.
This thesis demonstrates the potential of V-OCT as a tool for the diagnosis and assessment of the progression of optic nerve conditions. By gaining a deeper understanding of the biomechanical and hemodynamic intricacies of the ONH, we lay the groundwork for future explorations that hold promise for both glaucoma patients and astronauts.
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LHCb Upstream Tracker box : Thermal studies and conceptual designMårtensson, Oskar January 2016 (has links)
The LHC (Large Hadron Collider) will have a long shut down in the years of 2019 and 2020, referred to as LS2. During this stop the LHC injector complex will be upgraded to increase the luminosities, which will be the first step of the high luminosity LHC program (which will be realized during LS3 that takes place in 2024-2026). The LHCb experiment, whose main purpose is to study the CP-violation, will during this long stop be upgraded in order to withstand a higher radiation dose, and to be able to read out the detector at a rate of 40MHz,compared to 1MHz at present. This change will improve the trigger efficiency significantly. One of the LHCb sub-detectors the Trigger Tracker (TT), will be replaced by a new sub-detector called UT. This report presents the early stage design (preparation for mock-up building) of the box that will be isolating the new UT detector from the surroundings and to ensure optimal detector operation. Methods to fulfill requirements such as light and gas tightness, Faraday-cage behavior and condensation free temperatures, without breaking the fragile beryllium beam pipe, are established. / LHC (Large Hadron Collider) kommer under åren 2019-2020 att ha ett längre driftstopp. Under detta driftstopp så kommer LHC's injektionsanordningar att uppgraderas för att kunna sätta fler protoner i circulation i LHC, och därmed öka antalet partikelkollisioner per tidsenhet. Denna uppgradering kommer att vara första steget i "High Luminocity LHC"-programmet som kommer att realiseras år 2024-2026. LHCb-experimentet, vars främsta syfte är att studera CP-brott, kommer också att uppgraderas under stoppet 2019-2020. Framför allt så ska avläsningsfrekvensen ökas från dagens 1MHz till 40MHz, och experimentet ska förberedas för de högre strålningsdoser som kommer att bli aktuella efter stoppet 2024-2026. En av LHCb's deldetektorer, TT detektorn, kommer att bytas ut mot en ny deldetektor som kallas UT. Den här rapporten presenterar den förberedande designen av den låda som ska isolera UT från dess omgivning och försäkra optimala förhållanden för detektorn. Kraven på den isolerande lådan och tillvägagångssätt för att uppfylla dessa krav presenteras. / LHCb, LS2 and LS3 Upgrade
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Essays on optimal fiscal and monetary policiesKiarsi, Mehrab 01 1900 (has links)
Cette thèse se compose de trois articles sur les politiques budgétaires et monétaires optimales. Dans le premier article, J'étudie la détermination conjointe de la politique budgétaire et monétaire optimale dans un cadre néo-keynésien avec les marchés du travail frictionnels, de la monnaie et avec distortion des taux d'imposition du revenu du travail. Dans le premier article, je trouve que lorsque le pouvoir de négociation des travailleurs est faible, la politique Ramsey-optimale appelle à un taux optimal d'inflation annuel significativement plus élevé, au-delà de 9.5%, qui est aussi très volatile, au-delà de 7.4%. Le gouvernement Ramsey utilise l'inflation pour induire des fluctuations efficaces dans les marchés du travail, malgré le fait que l'évolution des prix est coûteuse et malgré la présence de la fiscalité du travail variant dans le temps. Les résultats quantitatifs montrent clairement que le planificateur s'appuie plus fortement sur l'inflation, pas sur l'impôts, pour lisser les distorsions dans l'économie au cours du cycle économique. En effet, il ya un compromis tout à fait clair entre le taux optimal de l'inflation et sa volatilité et le taux d'impôt sur le revenu optimal et sa variabilité. Le plus faible est le degré de rigidité des prix, le plus élevé sont le taux d'inflation optimal et la volatilité de l'inflation et le plus faible sont le taux d'impôt optimal sur le revenu et la volatilité de l'impôt sur le revenu. Pour dix fois plus petit degré de rigidité des prix, le taux d'inflation optimal et sa volatilité augmentent remarquablement, plus de 58% et 10%, respectivement, et le taux d'impôt optimal sur le revenu et sa volatilité déclinent de façon spectaculaire. Ces résultats sont d'une grande importance étant donné que dans les modèles frictionnels du marché du travail sans politique budgétaire et monnaie, ou dans les Nouveaux cadres keynésien même avec un riche éventail de rigidités réelles et nominales et un minuscule degré de rigidité des prix, la stabilité des prix semble être l'objectif central de la politique monétaire optimale. En l'absence de politique budgétaire et la demande de monnaie, le taux d'inflation optimal tombe très proche de zéro, avec une volatilité environ 97 pour cent moins, compatible avec la littérature. Dans le deuxième article, je montre comment les résultats quantitatifs impliquent que le pouvoir de négociation des travailleurs et les coûts de l'aide sociale de règles monétaires sont liées négativement. Autrement dit, le plus faible est le pouvoir de négociation des travailleurs, le plus grand sont les coûts sociaux des règles de politique monétaire. Toutefois, dans un contraste saisissant par rapport à la littérature, les règles qui régissent à la production et à l'étroitesse du marché du travail entraînent des coûts de bien-être considérablement plus faible que la règle de ciblage de l'inflation. C'est en particulier le cas pour la règle qui répond à l'étroitesse du marché du travail. Les coûts de l'aide sociale aussi baisse remarquablement en augmentant la taille du coefficient de production dans les règles monétaires. Mes résultats indiquent qu'en augmentant le pouvoir de négociation du travailleur au niveau Hosios ou plus, les coûts de l'aide sociale des trois règles monétaires diminuent significativement et la réponse à la production ou à la étroitesse du marché du travail n'entraîne plus une baisse des coûts de bien-être moindre que la règle de ciblage de l'inflation, qui est en ligne avec la littérature existante. Dans le troisième article, je montre d'abord que la règle Friedman dans un modèle monétaire avec une contrainte de type cash-in-advance pour les entreprises n’est pas optimale lorsque le gouvernement pour financer ses dépenses a accès à des taxes à distorsion sur la consommation. Je soutiens donc que, la règle Friedman en présence de ces taxes à distorsion est optimale si nous supposons un modèle avec travaie raw-efficace où seule le travaie raw est soumis à la contrainte de type cash-in-advance et la fonction d'utilité est homothétique dans deux types de main-d'oeuvre et séparable dans la consommation. Lorsque la fonction de production présente des rendements constants à l'échelle, contrairement au modèle des produits de trésorerie de crédit que les prix de ces deux produits sont les mêmes, la règle Friedman est optimal même lorsque les taux de salaire sont différents. Si la fonction de production des rendements d'échelle croissant ou decroissant, pour avoir l'optimalité de la règle Friedman, les taux de salaire doivent être égales. / This dissertation consists of three essays on optimal fiscal and monetary policies. In the first two essays, I consider New Keynesian frameworks with frictional labor markets, money and distortionary income tax rates. In the first one, I study the joint determination of optimal fiscal and monetary policy and the role of worker's bargaining power on this determination. In the second one, I study the effects of worker’s bargaining power on the welfare costs of three monetary policy rules, which are: inflation targeting and simple monetary rules that respond to output and labor market tightness, with and without interest-rate smoothing. In the third essay, I study the optimality of the Friedman rule in monetary economies where demand for money is motivated by firms, originated in a cash-in-advance constraint.
In the first essay, I find that when the worker’s bargaining power is low, the Ramsey-optimal policy calls for a significantly high optimal annual rate of inflation, in excess of 9.5%, that is also highly volatile, in excess of 7.4%. The Ramsey government uses inflation to induce efficient fluctuations in labor markets, despite the fact that changing prices is costly and despite the presence of time-varying labor taxes. The quantitative results clearly show that the planner relies more heavily on inflation, not taxes, in smoothing distortions in the economy over the business cycle. Indeed, there is a quite clear trade-off between the optimal inflation rate and its volatility and the optimal income tax rate and its variability. The smaller is the degree of price stickiness, the higher are the optimal inflation rate and inflation volatility and the lower are the optimal income tax rate and income tax volatility. For a ten times smaller degree of price stickiness, the optimal rate of inflation and its volatility rise remarkably, over 58% and 10%, respectively, and the optimal income tax rate and its volatility decline dramatically. These results are significant given that in the frictional labor market models without fiscal policy and money, or in the Walrasian-based New Keynesian frameworks with even a rich array of real and nominal rigidities and for even a miniscule degree of price stickiness, price stability appears to be the central goal of optimal monetary policy. Absent fiscal policy and money demand frictions, optimal rate of inflation falls to very near zero, with a volatility about 97 percent lesser, consistent with the literature.
In the second essay, I show how the quantitative results imply that worker's bargaining weight and welfare costs of monetary rules are related negatively. That is, the lower the bargaining power of workers, the larger the welfare losses of monetary rules. However, in a sharp contrast to the literature, the rules that respond to output and labor market tightness feature considerably lower welfare costs than the inflation targeting rule. This is specifically the case for the rule that responds to labor market tightness. The welfare costs also remarkably decline by increasing the size of the output coefficient in the monetary rules. My findings indicate that by raising the worker's bargaining power to the Hosios level and higher, welfare losses of the three monetary rules drop significantly and response to output or market tightness does not, anymore, imply lower welfare costs than the inflation targeting rule, which is in line with the existing literature.
In the third essay, I first show that the Friedman rule in a monetary model with a cash-in-advance constraint for firms is not optimal when the government to finance its expenditures has access to distortionary taxes on consumption. I then argue that, the Friedman rule in the presence of these distorting taxes is optimal if we assume a model with raw-efficient labors where only the raw labor is subject to the cash-in-advance constraint and the utility function is homothetic in two types of labor and separable in consumption. Once the production function exhibits constant-returns-to-scale, unlike the cash-credit goods model that the prices of both goods are the same, the Friedman is optimal even when wage rates are different. If the production function has decreasing or increasing-returns-to-scale, then to have the optimality of the Friedman rule, wage rates should be equal.
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Vliv sekuritizace na dynamiku cen bydlení ve Španělsku / Impact of Securitization on House Price Dynamics in SpainHejlová, Hana January 2014 (has links)
The thesis tries to explain different nature of the dynamics during the upward and downward part of the last house price cycle in Spain, characterized by important rigidities. Covered bonds are introduced as an instrument which may accelerate a house price boom, while it may also serve as a source of correction to overvalued house prices in downturn. In a serious economic stress, lack of investment opportunities motivates investors to buy the covered bonds due to the strong guarantees provided, which may in turn help to revitalize the credit and housing markets. To address such regime shift, house price dynamics is modelled within a framework of mutually related house price, credit and business cycles using smooth transition vector autoregressive model. Linear behaviour of such system is rejected, indicating the need to model house prices in a nonlinear framework. Also, importance of modelling house prices in the context of credit and business cycles is confirmed. Possible causality from issuance of covered bonds to house price dynamics was identified in this nonlinear structure. Finally, threat to financial stability resulting from rising asset encumbrance both in the upward and downward part of the house price cycle was identified, stressing the need to model impact of the covered bonds on house prices in...
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A ficção e o real: a importância da educação no século XIXCorrêa, Giseli Rodrigues 28 April 2009 (has links)
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Previous issue date: 2009-04-28 / Secretaria da Educação do Estado de São Paulo / It is an analysis of the education process in the formation of the youth in the XIX century, taking for base the works fiction of a Brazilian and Portuguese writers, besides the knowledge in place and texts about the ancient College Caraça, model in that epoch, situated in Minas Gerais.
Leaving from our research object, the novel O Ateneu, from Raul Pompéia, through the memories of Sérgio, the protagonist, revealed the function of one of the best colleges in Rio de Janeiro of the XIX century: austere discipline and basic mistakes not apparent at fathers eyes who were sending their children to study in the boarding school.
So, we like to answer the next question: might we understand that the character Sérgio reveals Pompéia, as soon as he reproduces the characteristics of his creator?
The identity of the character, trought the memory, can be seen as a projection of the author? The narrative elaborated of Sérgio perspective, already ripened through his impressions and sharp perception, analyses facts and situations that structured the social environment of the boarding school. The episodes served how revealed successive of the corruption and the moral misery that they were ruling in the traditional College Abílio, that it was frequented by Pompéia.
In this sense, it was possible to draw a parallel between this work and Os Maias and A Reliquia of Eça de Queiroz, since they show the importance of the education in the life s formation of Carlos Eduardo and Teodorico, that, unfortunately, little used it, because the first one, although it had an exemplary education financed by his grandfather, surrendered to the enchantments of his sister Maria Eduarda, that after surviving the incest and killed Afonso of displeasure; already the second used an education hypocritical and religious to inherit the fortune of his aunt, Sr.ͣ Patrocínio, and was unmasked through a relic.
All the novels wanted to show the importance of the education in the formation of people. Therefore, it was realized a research in a real establishment: the College Caraça, which worked like boarding school and seminar during the XIX century, to make a possible demonstration of model education; concern it was of Ramalho Ortigão with his children and his grandchildren / Trata-se de uma análise do processo educacional na formação da juventude no séc. XIX, tomando por base as obras ficcionais de um escritor brasileiro e de um português, além do conhecimento in loco e de textos a respeito do antigo Colégio Caraça, modelo na época, situado em Minas Gerais.
Partindo do nosso objeto de pesquisa, o romance O Ateneu, de Raul Pompéia, por meio das memórias de Sérgio, o protagonista, revelou o funcionamento de um dos melhores colégios cariocas do século XIX: disciplina austera e erros básicos não aparentes aos olhos dos pais, que enviavam seus filhos para estudar no internato.
Assim, desejamos responder à seguinte questão: poderíamos entender que a personagem Sérgio revela Pompéia, uma vez que reproduz as características de seu criador?
A identidade da personagem, pela memória, pode ser vista como uma projeção do autor? A narrativa elaborada a partir da perspectiva de Sérgio, já amadurecido por meio de suas impressões e percepção aguda, analisa fatos e situações, que estruturaram o ambiente social do internato. Os episódios serviram como desvelamentos sucessivos da corrupção e da miséria moral que imperavam no tradicional Colégio Abílio, do Barão de Macaúbas, colégio esse freqüentado por Pompéia.
Nesse sentido, foi possível traçar um paralelo entre essa obra e Os Maias e A Relíquia, de Eça de Queiroz, pois retratam a importância da educação na formação da vida das personagens Carlos Eduardo e Teodorico que, infelizmente, pouco a aproveitaram, pois o primeiro, embora tivesse uma educação exemplar financiada pelo seu avô, rendeu-se aos encantos de Maria Eduarda; que, posteriormente descobrirá ser sua irmã, vivendo o incesto e matando Afonso da Maia de desgosto; já o segundo utilizou-se da educação hipócrita e religiosa recebida para herdar os bens de sua tia, Sr.ͣ Patrocínio, tendo sido desmascarado por meio de uma relíquia.
Todos os romances desejaram mostrar a importância da educação na formação das pessoas. Por isso, foi realizada também uma pesquisa em um estabelecimento de ensino real: o Colégio Caraça, que funcionou como internato e seminário durante o século XIX, para tornar possível a demonstração de uma educação modelo; preocupação que era também a de Ramalho Ortigão com seus filhos e seus netos
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Exploration of the Cerebral Dysfunctions Induced by Arterial Rigidity and/or the Overexpression of TGFβ in a Mouse ModelBloch, Sherri 06 1900 (has links)
No description available.
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