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Envelope as Climate Negotiator: Evaluating adaptive building envelope's capacity to moderate indoor climate and energyJanuary 2013 (has links)
abstract: Through manipulation of adaptable opportunities available within a given environment, individuals become active participants in managing personal comfort requirements, by exercising control over their comfort without the assistance of mechanical heating and cooling systems. Similarly, continuous manipulation of a building skin's form, insulation, porosity, and transmissivity qualities exerts control over the energy exchanged between indoor and outdoor environments. This research uses four adaptive response variables in a modified software algorithm to explore an adaptive building skin's potential in reacting to environmental stimuli with the purpose of minimizing energy use without sacrificing occupant comfort. Results illustrate that significant energy savings can be realized with adaptive envelopes over static building envelopes even under extreme summer and winter climate conditions; that the magnitude of these savings are dependent on climate and orientation; and that occupant thermal comfort can be improved consistently over comfort levels achieved by optimized static building envelopes. The resulting adaptive envelope's unique climate-specific behavior could inform designers in creating an intelligent kinetic aesthetic that helps facilitate adaptability and resiliency in architecture. / Dissertation/Thesis / Ph.D. Environmental Design and Planning 2013
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Método para redução de mancha nas vedações externas de edifícios. / Method to reduce soiling deposition on building envelope.Flávio Leal Maranhão 11 December 2009 (has links)
O permanente contato das vedações externas dos edifícios com os materiais integrantes das vedações externas dos edifícios (fachadas e telhados) com os agentes de degradação provocam o surgimento de manchas, que normalmente estão associadas à deposição de poluentes e a proliferação de microorganismos. Para inibir o surgimento dessas manchas existem, atualmente, diversos métodos disponíveis, sendo que nenhum tem se mostrado efetivo. Esta tese de doutorado, com base em um extenso programa laboratorial - com o uso de métodos como MEV, FTIR, ângulo de contato, crescimento acelerado de microrganismos, atividade fotocatalítica, entre outros-, criou um novo método, destinado aos materiais de construção silicosos e porosos, que se baseia na modificação de suas propriedades superficiais, por meio da sobreposição de uma camada hidrofóbica por uma hidrofílica. Para se obter essa disposição superficial, utilizou-se um hidrofugante à de octil-silicone, que apresenta elevada repelência à água e maior durabilidade, e um semicondutor à base de dióxido de titânio, que apresenta atividade fotocatalítica quando incidido por radiação ultravioleta. Como resultado, o método proposto (denominado na tese por WR+TiO2-sequencial) apresenta, comprovadamente, os seguintes benefícios: (i) redução de manchas causadas pela adesão de partículas com características apolares, similares às partículas de poluição dos grandes centros urbanos; (ii) limpeza espontânea de certos tipos de manchas, decorrentes dos processos fotocatalíticos que promovem a oxidação/redução de matéria orgânica; (iii) inibição do crescimento de microrganismo em escala laboratorial; (iv) redução da absorção total de água e, principalmente, da cinética do ganho de massa. Por isso, edificações cujas vedações externas venham a ser tratadas com o método aqui proposto são, potencialmente, células ativas para a sustentabilidade do ambiente construído, pois: reduzem o consumo de energia, reduz os custos de manutenção e contribuem para despoluição da atmosfera urbana. / Building roofs and façades usually show blackening surfaces after few years in large cities. On porous and silicious materials those soiling is caused by particles pollution depositions and mould growth, and the available methods available to prevent this phenomenum do not have a good performance along its service life. This thesis, based on an intensive laboratory research with many test technics as SEM, FTIR, contact angle, accelerated mould growth, and photocatalytical activity, create a new method to prevent soiling on porous and silicous building materials. This method modify the materials surface properties, making the outer surface layers with nano-actived titanium dioxide particles, which has photocatalitycal activity under UV radiation, and below it a hydrophobic layer, composed by octyl-silicones. The main results in laboratory scale experiments obtained by this new method (so-called in this thesis by WR+TiO2-sequencial) are: (i) stainings reductions caused by apolar agent, (ii) self-cleaning properties for some stain and after UV radiation exposition, (iii) mould growth resistance, and (iv) water absorption reduction. As a consequences, building envelopes trated with the new method is supposed to contribute to built and environment sustantability, because: can reduce the energy consumption, reduce de maintenance costs e has a de-pollution properties.
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Codage de l'enveloppe temporelle dans le nerf auditif / Temporal envelope coding of sound in the auditory nerveHasselmann, Florian 21 November 2017 (has links)
Contexte : La compréhension de la parole dans le silence est dépendante des mécanismes de codage de l’enveloppe temporelle du signal sonore. Une anomalie du codage (d’origine infectieuse, immunitaire, génétique, tumorale, ou environnementale) entraine irrémédiablement une diminution des performances audiométriques vocales. Les méthodes d’exploration fonctionnelle de la cochlée (potentiels d’action composite du nerf auditif, potentiel évoqués auditifs précoces) utilisent des stimuli sonores simples (clics, bouffées tonales) pour détecter une anomalie de codage des indices temporels. Le but de cette étude était de développer une méthode électrophysiologique capable de mesurer les réponses du nerf auditif à des stimuli modulés en amplitude.Matériel et méthodes : La réponse électrophysiologique du nerf auditif a été mesurée à l’aide d’une électrode placée sur la niche de la fenêtre ronde de la cochlée de gerbilles et de rats vieillissants. Les stimuli acoustiques consistaient en des bandes de bruit de 20 secondes modulées sinusoïdalement en amplitude et centrées sur 4, 8 et 16 kHz. Nous avons étudié le niveau, la profondeur de modulation, la fréquence de modulation et la fréquence porteuse.Résultats : Notre étude sur le modèle de perte sélective neuronale (ouabain) montre que l’analyse des potentiels globaux cochléaires permet de détecter une perte de fibres à basse activité spontanée dans le nerf auditif, résultat important car indétectable (« surdités cachées ») actuellement avec les tests utilisés en routine en clinique (EcoG et PEA) (Batrel, Huet, Hasselmann et al, Plos One 2017). Ensuite, en combinant le stimulus de cette étude avec une fonction sinusoïdale, nous avons développé et validé une méthode pour évaluer la qualité de codage de l’enveloppe par le nerf auditif. Nous avons appliqué cette méthode sur un modèle de vieillissement (rat Sprague-Dawley). Nos résultats suggèrent que le viellissement entraine une modifcation du phénotype des fibres du nerf auditif sans pertes de fibres associées (article Occelli, Hasselmann et al, soumis à eNeuro). Conclusion : Notre travail démontre qu’il est indispensable d’élargir le nombre de techniques d’exploration fonctionnelle de la cochlée car les tests utilisés en routine en clinique ne permettent pas de déceler des déficits subtils d’encodage dans le nerf auditif. La mesure de l’activité soutenue des fibres permet de détecter la perte sélective des neurones à basse activité spontanée, indétectable avec les méthodes classiques. Le changement de phénotype des fibres observé au cours du vieillissement du rat Sprague-Dawley est détectable avec notre méthode alors qu’il ne l’est pas avec le potentiel d’action composite du nerf auditif. / Background: Speech intelligibility in quiet is critically dependent on the temporal envelope of a sound signal. An abnormal coding of this temporal cue (due to infectious, immune, genetic, tumoral or environmental of origin) implies a decrease of speech recognition scores. The current proxy to probe deafness in clinical framework (Compound Action Potential of the auditory nerve, auditory brainstem responses) uses simplistic stimuli (clicks, tone bursts) to detect a such abnormal coding of the temporal cues. The aim of this study was to develop a new electrophysiology method in murins able to measure the auditory nerve responses to amplitude-modulation stimuli.Material and methods: The electrophysiology response of the auditory nerve was recorded using an electrode implanted onto the round window niche on normal-hearing gerbil cochlea and aging rat cochlea. The acoustical stimuli consisted of 20 seconds sinusoidally amplitude-modulated noise-band centered on 4, 8 and 16 kHz. We have studied varying sound level, the modulation depth, the modulation frequency and the carrier frequency.Results: Our study on the selective fiber loss ouabain model show the mass potentials recorded at the round window enable the detection of low spontaneous rate fibers in gerbil auditory nerve. This result is important because the current clinical used tests aren’t enough sensitive to detect a such coding impairment (CAP, ABR) (Batrel, Huet, Hasselmann et al., 2017). Then we combined the stimulus of this previous study with a sinusoidal function to develop a new method to assess the envelope coding by the auditory nerve. We validated this new method. Last, we used our method on an aging model (Sprague-Dawley rat). Our results suggest aging leads to a phenotype change of auditory nerve fibers without associated fiber loss (article Occelli, Hasselmann et al, submitted to eNeuro).Conclusion: Our study shows it’s indispensable to expand the number of tools to probe the cochlea because the current clinical used tests aren’t enough sensitive to detect subtle deficits of encoding in the auditory nerve. The recording of the fiber sustained activity enable to detect the selective loss of low-spontaneous rate neurons. A such loss is undetectable with classical clinical tools. The phenotype change of fibers we observed in aging Sprague-Dawley rats is detectable with our method whereas it’s not using the compound action potential of the auditory nerve.
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Conception d’amplificateurs de puissance reconfigurables en technologie CMOS avancée pour une application 4G LTE / Design of reconfigurable power amplifiers in CMOS technology dedicated to 4G LTE applicationTuffery, Adrien 20 December 2012 (has links)
Cette thèse porte sur la conception d’amplificateurs de puissance reconfigurables en technologie CMOS avancée pour une application cellulaire de 4ème génération. Dans les systèmes de communication sans fil, le rendement énergétique est un critère primordial qui impacte la durée d’utilisation de la batterie. Principalement déterminé par la consommation d’énergie du transmetteur, il est plus particulièrement lié à celle de l’amplificateur de puissance (PA). Pour les terminaux mobiles de 4ème génération (4G), les techniques de transmission et les modulations utilisées pour atteindre les débits de données visés induisant une dynamique importante du signal à transmettre, l’implémentation de techniques d’amélioration du rendement autour du PA devient indispensable, afin de le reconfigurer en puissance.Nous avons mis au point dans ce travail de recherche des architectures innovantes utilisant les techniques d’amélioration du Power Cell Switching (PCS) et de l’Envelope Tracking (ET). Le double objectif visé étant d’améliorer significativement le rendement pour les faibles niveaux de puissance et d’apporter de la flexibilité par rapport à un PA utilisé seul. Une première architecture utilisant la technique du PCS totalement intégré en technologie CMOS 65nm de STMicroelectronics, mettant en œuvre des transformateurs comme combineurs de puissance, a été réalisée pour valider la fonctionnalité du concept proposé. Puis une deuxième architecture combinant les techniques du PCS et de l’ET a été conçue, afin d’évaluer les avantages qu’apporte la combinaison de ces deux techniques par rapport à un PA fonctionnant seul et à un PA développé utilisant la technique du PCS. / This thesis deals with the design of reconfigurable power amplifiers implemented in CMOS technology for 4G LTE application. For the next generation communication systems such as 4G LTE, orthogonal frequency division multiplexing (OFDM) is employed for a wideband communication. Indeed, signal information is encoded both in amplitude and phase domains, which results in a higher peak to average power ratio than for 2G and 3G systems. Consequently, the overall power amplifier (PA) efficiency does not only depend on efficiency at maximum power, but also and mainly on efficiency at back-off level where the PA operates most of the time. Obviously, classical PA architectures do not address this problem, because it can only achieve maximum efficiency at a single power level, usually around the peak output power. Therefore, the overall efficiency of the PA is considerably low and efficiency improvement techniques are required to increase the battery life-time. This thesis exposes innovative architectures using Power Cell Switching (PCS) and Envelope Tracking (ET) techniques. The main objective of the proposed architectures is to significantly improve the average efficiency in comparison with a stand-alone power amplifier at power back-off. Consequently, a reconfigurable PA architecture using a 4-step PCS technique has been implemented in CMOS 65nm technology. A second architecture was designed to evaluate the improvement obtained with the combination of these two techniques.
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Spécificités et enjeux théorico-cliniques des groupes thérapeutiques pour patients schizophrènes / Specificities and theoretical-clinical stakes of therapeutic groups for schizophrenic patientsVollon, Clarisse 12 May 2017 (has links)
Notre pratique clinique dans le cadre de groupes thérapeutiques pour patients schizophrènes nous a conduit à nous interroger sur les spécificités métapsychologiques de ce type de dispositif de soins. En nous intéressant aux premières séances d’un groupe psychanalytique de paroles et d’un psychodrame psychanalytique de groupe mené dans une unité de soins et de réinsertion avec des patients schizophrènes adultes hospitalisés depuis de nombreuses années, nous avons dégagé quatre hypothèses. Elles concernent la construction et la structuration de ces deux groupes via l’observation de la texture de leur enveloppe psychique groupale respective, l’organisation de la groupalité psychique interne des patients schizophrènes durant les premières séances, et la nature du transfert psychotique groupal. En utilisant une méthode clinique, nous avons tenté de montrer que ce travail de recherche permet plus globalement d’envisager une nouvelle articulation des modèles psychanalytiques du groupe déjà existant, la nécessité de proposer de nouveaux outils méthodologiques pour étudier la concaténation des chaînes associatives individuelles et groupales, ainsi que les enjeux thérapeutiques de ces thérapies. / Our clinical practice as part of group therapy for schizophrenic patients has led us to question the metapsychological characteristics of this type of care device. As we interested in the first sessions of a psychoanalytic support group and a psychoanalytic psychodrama conducted in a group care and rehabilitation unit with adult schizophrenic patients hospitalized for many years, we have identified four assumptions. They concern the construction and structuring of these two groups through the observation of the texture of their respective group psychical envelope, organizing the internal psychic groupality schizophrenic patients during the first sessions, and the nature of groupal psychotic transference. Using a clinical method, we tried to show that this research allows more broadly to consider a new articulation of psychoanalytic models of existing group, the need to propose new methodological tools to study the concatenation of the individual associative chains and groupal and therapeutic issues of these therapies.
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Comprendre la flexibilité génétique de la protéine d’enveloppe de VIH-1 à travers l’étude du réseau de coévolution de ses acides aminés / Understanding the genetic flexibility of the HIV-1 envelope protein through the study of the network of its coevolving amino acidsGasser, Romain 13 June 2016 (has links)
Une des caractéristiques du Virus de l’Immunodéficience Humaine de type 1 (VIH-1) est sa diversification génétique extensive, qui lui permet d’échapper au système immunitaire. Néanmoins, il est nécessaire que le taux de mutation requis pour à cette évolution rapide ne compromette pas la fonctionnalité de ses protéines. Les travaux présentés ici ont eu pour objectif l’étude des réseaux de coévolution qui composent les glycoprotéines d’enveloppe (Env) afin de comprendre les règles qui sous-tendent leur évolution. Il a été mis en évidence que les régions variables de ces protéines, grâce à leur flexibilité structurelle, peuvent aussi servir à faciliter l’incorporation de mutations touchant les régions plus constantes. De plus, un réseau de coévolution impliqué dans les changements de conformations nécessaires à l’activité de Env a été identifié, soutenant le fait que ces régions variables ont un rôle central dans ces changements. Ces études démontrent le rôle crucial joué par les régions variables en dévoilant un nouvel aspect de leur contribution à l’évolution du VIH-1. / The Human Immunodeficiency Virus type 1 (HIV-1) is characterized by an extensive genetic diversification of its strains that allows the virus to escape the immune system. However, the mutation rate needed for this rapid evolution must not compromise the functionality of the viral proteins. The aim of the work presented here has been to study the coevolution networks that constitute the envelope glycoproteins (Env) in order to understand the rules driving their evolution. The results have highlighted that variable regions, thanks to their structural freedom, can facilitate the incorporation of mutations in more constant regions. Moreover, a coevolution network involved in the conformational changes required for the activity of Env has been identified, underlining the central role played by variable regions in these processes. Besides underscoring the crucial role played by variable regions in the functionality of Env, these studies unveil a new aspect of their contribution to HIV-1 evolution.
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Analysis, measurement and cancellation of the bandwidth and amplitude dependence of intermodulation distortion in RF power amplifiersVuolevi, J. (Joel) 05 October 2001 (has links)
Abstract
The main emphasis in modern RF power amplifier (PA) research is on
improving
linearity while at the same time maintaining reasonably good efficiency, for
which purpose external linearization in the form of feedforward or predistortion
is often used. Linearity and linearization can be considered from both a
fundamental signal (amplitude and phase conversions, AM-AM & AM-PM) and an
intermodulation distortion (IMD) regeneration point of view, and since a study of
intermodulation gives more information on the behaviour of an amplifier,
linearity is studied in this thesis by analysing the amplitude and phase of IM
components under varying signal conditions, i.e. as functions of temperature,
modulation bandwidth and amplitude.
To study the behaviour of IM components analytically, a Volterra model including
electro-thermal distortion mechanisms is developed and a simulation technique is
introduced to determine how easily the amplifier can be linearized. An
S-parameter characterization method for extracting the Volterra model and the
simulation model is developed, and the amplitude and phase dependences of the IM
components are shown by means of measurements performed by a novel technique
developed here. The results show that the behaviour of IM components is more
complicated than had commonly been expected.
Three techniques are developed for eliminating the frequency dependence of IM
components, impedance optimization, envelope filtering and envelope injection. In
the envelope injection technique, a low frequency envelope signal is added to the
input of the amplifier in order to improve both the bandwidth and amplitude range
of the memoryless predistortion. The functionality of envelope injection is
demonstrated by Volterra calculations, simulations and measurements, and the
technique is applied to 1W, 1.8 GHz common-emitter BJT and common-source MESFET
amplifiers. IM cancellation better than 20 dB is achieved over a wide range of
bandwidths and amplitudes.
It is concluded that an inherently linear amplifier is not necessarily easy to
linearize any further using external techniques, but that the part of the
distortion that varies with bandwidth and amplitude can be cancelled out using
envelope injection and the remaining memoryless distortion by means of a simple
polynomial RF predistorter. This results in good cancellation of distortion, and
since both envelope injection and RF predistortion consume little power, both
good efficiency and linearity can be achieved.
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Identification and characterization of protein-protein interactions in the nuclear envelopeVijayaraghavan, Balaje January 2017 (has links)
The nuclear envelope forms the interface between the nucleus and the cytoplasm. The nuclear envelope consists of the two concentric lipid membranes, the nuclear pores and the nuclear lamina. The inner nuclear membrane contains hundreds of unique transmembrane proteins showing high tissue diversity. Mutations of some proteins in the nuclear envelope give rise to a broad spectrum of diseases called envelopathies or laminopathies. In this thesis, I aimed to study the functional organization of the nuclear envelope by identifying and characterizing interactions between the nuclear envelope proteins. For this, we developed a novel method called the Membrane Protein Crosslink Immuno-Precipitation, which enable identification of protein-protein interactions in the nuclear envelope in live cells. We identified several novel interactions of the inner nuclear membrane protein, Samp1, and studied the interaction between the Samp1 and the nuclear GTPase, Ran in detail. Samp1 can bind to Ran and is thus the first known transmembrane Ran binding protein and Samp1 might provide a local binding site for Ran in the inner nuclear membrane. We found that Samp1 also binds to the inner nuclear membrane protein, Emerin and Ran can regulate the Samp1-Emerin interaction in the nuclear envelope. During mitosis, Samp1 distributes in the mitotic spindle. Therefore, we investigated a possible functional role of Samp1 in the mitotic machinery. Samp1 depletion resulted in aneuploid phenotypes, metaphase prolongation and decreased distribution of γ-tubulin and β-tubulin in the mitotic spindle. We found that Samp1 can bind to γ-tubulin, which is essential for the microtubule nucleation and hence for the spindle stability. The new interesting features of Samp1 provide insights on the unforeseen functions of the nuclear envelope proteins. / <p>At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 3: Manuscript. Paper 4: Manuscript.</p>
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The Amyotrophic Lateral Sclerosis 8 Mutant VAPB-P56S Causes a Nuclear Envelope and Nuclear Pore DefectChalhoub, Antonious January 2012 (has links)
A P56S mutation in the VAPB MSP domain is linked to adult-onset amyotrophic lateral sclerosis 8. The objective of this study is to characterize the functional role of VAPB in transport of NE and NPC proteins from the ER to the NE. Over-expression of VAPB-P56S blocked the transport of nucleoporins (Nups) and NE proteins, resulting in their sequestration in dilated cytoplasmic membranes. Simultaneous overexpression of the FFAT motif (two phenylalanines in an acidic track) antagonizes mutant VAPB effects and restores transport to the NE. VAPB function is required for transport to the NE because knockdown of endogenous VAPB recapitulates this phenotype. Moreover, the compartment in which Nups and NE proteins are sequestered and retained was identified as ER-Golgi intermediate compartment (ERGIC). Moreover, a defect in the transport of NE and NPC proteins attenuates nucleocytoplasmic shuttling of the glucocorticoid receptor (GR). Further, VAPB-P56S which is only soluble in SDS was solubilized in the Triton-X-100 fraction similar to VAPB-WT upon co-transfection with the FFAT motif suggesting that FFAT interacts with the insoluble VAPB-P56S protein changing its biophysical properties.
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Molecular gas around the binary star R AquariiOlander, Terese January 2017 (has links)
At the end of the lives of low- to intermediate mass stars they can be found on the asymptotic giant branch (AGB). The AGB phase ends when the entire circumstellar envelope (CSE) is blown away in a superwindphase, in the end creating a planetary nebula. It is unknown what shapes the CSE and the planetary nebula. Binarity is a favored theory. In order to test this theory the CSE around the star R Aquarii has been studied using the emission from different molecules observed with ALMA. R Aquarii is a nearby binary system and therefore easy to study. The system consists of a Mira variable on the AGB and a hot white dwarf. It was found that only in the emission from the 12CO J=3–2 transition were the CSE resolved enough for any structure to be seen. The morphology was irregular and no clear symmetry was seen. A spot in the same molecular line was detected at high velocities (v = -23 km/s) relative to the star at a projected distance of 7 arcsec south of R Aqr. Line profiles for 12CO and 13CO follow the same shape but differs in magnitude, indicating that they can be found in the same structure. A mass loss rate of 6.5·10-7 solar masses per year was calculated for R Aquarii using line intensities obtained from the line profile of 12CO. The morphology and kinematics of the CO CSE of R Aquarii are discussed within the limitations of the current data set. More observations with better resolution are needed to better understand the morphology of the CSE of R Aquarii and draw firm conclusions.
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