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Holden, James Anthony, and jamesholden@netspace net au. "Vaccination Strategies for the Prevention of Swine Dysentery." RMIT University. Applied Sciences, 2006. http://adt.lib.rmit.edu.au/adt/public/adt-VIT20070112.122102.
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The SmpA outer membrane lipoprotein of B. hyodysenteriae has several characteristics that indicate the potential to protect against swine dysentery (SD). It localises to the outer membrane and antibodies directed against SmpA can prevent the growth of B. hyodysenteriae in vitro. There is some variation observed in the distribution and expression of the SmpA lipoprotein, suggesting that vaccination with SmpA may not provide protection against challenge with a heterologous B. hyodysenteriae strain. This study has characterised the variation at the smpA locus, and in the process has identified a novel gene, smpB. There is very low similarity between smpB and smpA, with the exception of an identical lipoprotein signal sequence. This suggests that SmpB may be translocated to the outer membrane of B. hyodysenteriae in a similar fashion to SmpA. The results described in this thesis indicate that strains of B. hyodysenteriae harbour either smpA or smpB, but not both, explaining the earlier results of Turner et al. (1991). The presumed outer membrane location of SmpB lead to further investigations into its potential to protect mice from infection with B. hyodysenteriae. Swine Dysentery is a inflammatory disease of the swine colon. Therefore it is believed that a mucosal immune response may provide increased protection against challenge. In this study, vaccination of mice with recombinant SmpB elicited high levels of serum antibodies, induced the production of Interleukin-4 producing T lymphocytes and decreased the observed histological effects after challenge with virulent B. hyodysenteriae. In efforts to increase the protected conferred by vaccination with SmpB, recombinant Salmonella typhimurium STM-1 vaccines were created to express SmpB or deliver DNA vaccines encoding SmpB. Vaccination with these recombinant Salmonella vectors did not induce a measurable SmpB specific immune response. Macrophage survival and plasmid stability studies indicated that this was due to instability of the expression plasmids in STM-1. Although SmpB will only ever protect against strains of B. hyodysenteriae harbouring smpB, these results indicate that with further research, SmpB (and SmpA) may contribute to protection from SD. Toxin production is an important aspect of the pathogenesis of many pathogenic bacteria. Vaccination with attenuated toxins is commonly used to prevent disease. In this study, the B. hyodysenteriae â-haemolysin HlyA was used to vaccinate mice to determine the protection induced after challenge. Vaccination of mice with recombinant HlyA induced significant levels of serum antibodies and lowered the observed pathological effects after challenge of vaccinated mice with virulent B. hyodysenteriae. In an attempt to increase the mucosal immune response and therefore the protection afforded after vaccination with HlyA, recombinant S. typhimurium STM-1 strains were created to express HlyA or deliver DNA vaccines encoding HlyA. Similar to the recombinant STM-1 vaccines expressing SmpB, a HlyA specific immune response was not observed by ELISA or ELISPOT analysis. Plasmid stability trials revealed that the inability to induce a detectable HlyA specific immune response by recombinant STM-1 vaccination may be due to ins tability of the plasmids. Outer membrane proteins are often important components of vaccines against bacterial and viral pathogens. Considering the variation observed in the smpA locus in this study resulting in the identification of smpB, further investigation into the distribution and conservation of outer membrane encoding genes in B. hyodysenteriae strains was undertaken. In particular, the blpAEFG, vspABCD and vspEFGH clusters were analysed for their distribution. It was demonstrated that genes that are B. hyodysenteriae specific (vspABCD and vspEFGH) displayed higher levels of polymorphism than those that are distributed amongst non-pathogenic species, such as B. innocens (which contains blpAEFG). This suggests that the variation in the vspABCD and vspEFGH clusters amongst B. hyodysenteriae strains may be a result of the exposure to the host immune system. Further investigation was undertaken by PFGE analysis and 2D-gel electrophoresis, to analyse genomic and proteomic variation at a global level. Although strains of B. hyodyse nteriae produced several different electrophoretic types (ET) upon PFGE analysis, only limited correlation between the PFGE ET, the polymorphisms in vspABCD and vspEFGH and the presence of smpA/smpB were observed. 2D-gel electrophoresis analysis of outer membrane preparations of two B. hyodysenteriae strain revealed several distinct differences in the outer membrane between B. hyodysenteriae strains. The observed differences in the proteins contained in the outer membrane of B. hyodysenteriae is important for vaccine design, as the induction of cross protection between strains of B. hyodysenteriae is essential for a effective vaccine.
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Parveg, Dristy Rahul. "A Study of Different Switched Mode Power Amplifiers for the Burst Mode Operation." Thesis, University of Gävle, Department of Technology and Built Environment, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-3090.
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<p>Power-amplifier efficiency is a significant issue for the overall efficiency of most wireless system. Therefore, currently there are different kind of Switched mode power amplifiers are developed which are showing very high efficiency also at higher frequencies but all of these amplifiers are subjected to drive with the constant envelope signals. Whereas, for the increasing demand of high data rate transmissions in wireless communication there are some new modulation schemes are introduced and which are generating no more a constant envelope signal but a high peak to average power signal. Therefore, recently a new technique is proposed called the burst mode operation for operating the switched mode power amplifiers efficiently while driven by a high peak to average power signal.</p><p> </p><p>The purpose of this master thesis work was to review the theory of this burst mode operation and some basic investigations of this theory on switched mode power amplifiers were performed in simulation environments. The amplifiers of class D, inverse D, DE and J are studied. The thesis work was mainly carried out by ADS and partly in MATLAB SIMULINK environment. Since this burst mode operation is a completely new technique therefore a new Harmonic balance simulation setups in ADS and Microwave Office are developed to generate the RF burst signals.</p><p> </p><p>A Class J amplifier based on LDMOS technique is measured by a 16 carrier multi-tone signal having peak to average power ratio of 7 dB and achieved the drain efficiency of 50% with -30 dBc linearity at 946 MHz.</p><p> </p><p> </p>
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Ramadan, Alaaeddine. "Amplification de puissance à haut rendement en bande L et en technologie GaN intégrant une pré formation de la tension de commande d'entrée." Limoges, 2010. https://aurore.unilim.fr/theses/nxfile/default/ffee17f3-34c5-439b-8f3b-a0e896c80931/blobholder:0/2010LIMO4016.pdf.
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La technologie de semi-conducteurs de puissance GAN est en pleine phase de développement à l'heure actuelle et offre de réelles potentialités pour la génération de fortes puissances à l'état solide en hyperfréquence. Le sujet de thèse concerne donc l'étude de l'amplification de puissance en commutation en technologie GaN avec la réalisation d'un démonstrateur à 2 GHz sur la base d'une puissance de sortie de 15Watts. L'étude aboutit à un contrôle et une préformation adéquats des harmoniques de courants et de tensions en entrée et en sortie de l'étage de puissance. Un point innovant et central de ce travail de thèse a été l'analyse multi-harmonique conjointe entre l'étage 'driver' et l'étage de puissance pour préformer le signal de commande de l'étage de puissance et aboutir à un fonctionnement optimisé en rendement sur une large bande passante. Les travaux de thèse se sont concrétisés par la réalisation d'un amplificateur démonstrateur à deux étages comprenant un premier étage fonctionnant en classe F inverse et un second étage fonctionnant en classe F. Cette réalisation est par nature adressable à l'amplification de signaux à enveloppe constante ne nécessitant pas de spécifications contraignantes en terme de linéarité<br>High efficiency performances of microwave power amplifiers are reached by implementing proper matching conditions at harmonic components. Harmonic tuned amplifiers offer for the moment the best energy conversion efficiency between DC supply and RF power at fundamental frequency available in a 50 Ω load. In addition to proper harmonic terminations, the minimization of power losses at fundamental frequency in the output RF matching and power combining circuit is of prime importance. This has been widely reported over the past few years. Considering this main aspect GaN technology offers an evident advantage due to its high drain voltage operation capability that is beneficial for designing low loss and wideband output matching circuits. Several works have been reported during the past few years. This work examines power added efficiency improvements by implementing an appropriate gate source voltage waveform shaping of power cells. Analytical calculations, circuit simulations using a nonlinear model of a 15W GaN HEMT and a two stage power amplifier design have been achieved. The power stage operates at high drain bias voltage under class F conditions while the driver stage operates at low drain bias voltage under inverse class F conditions to drive the input of power stage by an appropriate gate source voltage waveform shape. Very good power added efficiency have been reached over a wide frequency bandwidth. This work addresses the amplification of constant envelope signals that do not require any stringent specification in terms of linearity
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Souri, Mohammad. "FINITE ELEMENT MODELING AND FABRICATION OF AN SMA-SMP SHAPE MEMORY COMPOSITE ACTUATOR." UKnowledge, 2014. http://uknowledge.uky.edu/me_etds/38.
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Shape memory alloys and polymers have been extensively researched recently because of their unique ability to recover large deformations. Shape memory polymers (SMPs) are able to recover large deformations compared to shape memory alloys (SMAs), although SMAs have higher strength and are able to generate more stress during recovery.
This project focuses on procedure for fabrication and Finite Element Modeling (FEM) of a shape memory composite actuator. First, SMP was characterized to reveal its mechanical properties. Specifically, glass transition temperature, the effects of temperature and strain rate on compressive response and recovery properties of shape memory polymer were studied. Then, shape memory properties of a NiTi wire, including transformation temperatures and stress generation, were investigated. SMC actuator was fabricated by using epoxy based SMP and NiTi SMA wire. Experimental tests confirmed the reversible behavior of fabricated shape memory composites.
The Finite Element Method was used to model the shape memory composite by using a pre-written subroutine for SMA and defining the linear elastic and plastic properties of SMP. ABQUS software was used to simulate shape memory behavior. Beside the animated model in ABAQUS, constitutive models for SMA and SMP were also developed in MATLAB® by using the material properties obtained from experiments. The results of FEM simulation of SMC were found to be in good agreement with experimental results.
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Ohlenroth, Matthias, and Thomas Radke. "Linux SMP." Universitätsbibliothek Chemnitz, 1998. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-199800243.
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Rashid, S. M. Shahriar. "Design and Heterogeneous Integration of Single and Dual Band Pulse Modulated Class E RF Power Amplifiers." The Ohio State University, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=osu1543505207173487.
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Laaksonen, Mikael. "A reliable SMPP implementation in Erlang." Thesis, Uppsala universitet, Institutionen för informationsteknologi, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-204894.
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Software failure is one of the main problems in computer systems. Especially in systems with demand for high availability, such as telecom systems. SMPP is a protocol for sending short messages between entities in the telecom network. This thesis describes the design and implementation of a highly fault tolerant and reliable SMPP server and client. The implementation is done in Erlang, a language that was designed for fault tolerance. After testing the fault tolerance, the developed software has been integrated into telecommunication systems in commercial use at Mobile Arts.
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Austin, Ty (Roydrick Tyrone). "Makivism design : Social Media Participatory Design (SMPD)." Thesis, Massachusetts Institute of Technology, 2018. http://hdl.handle.net/1721.1/118500.
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Thesis: S.M. in Architecture Studies, Massachusetts Institute of Technology, Department of Architecture, 2018.<br>Cataloged from PDF version of thesis. "June 2018."<br>Includes bibliographical references (page 60).<br>We live in a world today where instantaneous transparency is the rule of thumb. Social media platforms such as Facebook or Linkedin have become the primary modes of communication and connectivity amongst professional and personal circles. Building Information Modeling, or BIM, is a 3D parametric modeling software. BIM visually assists architecture and engineering design teams remotely collaborate, innovate, and connect instantaneously with colleagues clients in more productive ways to create efficient construction projects. However, BIM's strengths in efficient transparency are often not extended to the principal stakeholders of any project: the community. This thesis will examine an intersectional interest known as Social Media Participatory Design (SMPD) or Makivism Design. SMPD is the integration of both 3D parametric modeling with social media. Network platforms, such as Facebook or Linkedin, are the primary modes of communication and connectivity amongst design professionals and community leaders today. By implementing SMPD into the built environment sector, community stakeholders can attain instantaneous access into the design process of a project through their favorite social media app. The primary research objective of this thesis is examine whether SMPD provides the designer, or user, the knowledge and communication they need to make the informed, transparent and inclusive design making decisions needed to collaborate on community-based projects. We will determine whether SMPD has the potential to empower those who feel marginalized and demand designers and clients alike to be more inclusive.<br>by Ty Austin.<br>S.M. in Architecture Studies
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Daniels, Michael John. "Metal binding to the cyanobacterial metallothionein SmtA." Thesis, University of Newcastle upon Tyne, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.314096.
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Vouillot, Léna. "Développement des motoneurones chez un modèle amphibien d'amyotrophie spinale généré à l'aide de nucléases." Thesis, Evry-Val d'Essonne, 2014. http://www.theses.fr/2014EVRY0038.
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Les amyotrophies spinales proximales sont des maladies génétiques neuromusculaires caractérisées par la dégénérescence des motoneurones spinaux et une atrophie des muscles squelettiques proximaux. La perte de fonction du gène smn1, un gène essentiel à la survie des motoneurones, entraîne une réduction drastique du niveau de protéine SMN et est, à l’origine des symptômes observés chez les patients. L'amphibien anoure Xenopus tropicalis constitue un très bon petit animal modèle pour étudier cette maladie ainsi que le développement des motoneurones. En effet une diminution de la production de la protéine SMN via l’utilisation de morpholinos a permis de montrer chez les têtards, des défauts de migration des motoneurones ainsi qu’une atrophie des muscles caudaux. Pour développer un modèle héritable de SMA, nous avons utilisé des nucléases tels que les ZFN ou le système CRISPR/Cas pour générer des mutations du gène smn chez Xenopus tropicalis. Nous avons conçu les outils moléculaires pour induire différentes mutations du gène smn avec des ZFN ou le système CRISP/Cas9. Nous avons ensuite validé l'efficacité de ces nucléases dans des embryons in vivo et développé une méthode de recherche de mutations basée sur l’utilisation des endonucléases T7EI et Surveyor. Nous avons obtenu un animal fondateur mutant qui permettra de générer des embryons homozygotes pour la mutation. En parallèle, nous avons développé une lignée transgénique chez Xenopus tropicalis permettant de visualiser les populations de motoneurones spinaux, pour mieux caractériser les animaux mutants smn in vivo. La combinaison de ces deux lignées permettra de mieux comprendre la physiopathologie motoneuronal liée à des mutations de smn<br>Spinal muscular atrophy (SMA) is a neurodegenerative disease characterized by motor neuron loss and skeletal muscle atrophy. In human the loss of function of the smn1 gene, the main supplier of survival motor neuron protein (SMN), leads to reduced levels of SMN and eventually to SMA. The anuran amphibian Xenopus tropicalis is a good animal model for the study of SMA and motor neurons development. Indeed the inhibition of the production of SMN using antisense morpholinos leads to caudal muscular atrophy in tadpoles. To develop an inheritable SMA model, we edited the smn gene in X. tropicalis using zinc-finger nucleases (ZFNs) and CRISPR/Cas system. As a first step, we designed the molecular tools needed to induce mutations of the smn gene using ZFN and CRISPR/cas9. Next we probed the efficiency of these tools and developed a method to identify mutations using T7EI and Surveyor endonucleases. We obtained a mutant frog and thus we will be able to produce homozygous mutant embryos for smn. In parallel we developed a transgenic line of Xenopus tropicalis frogs in which we can image motor neurons populations in vivo. The combination of both lines should enable to increase our knowledge and understanding of motor neuron physiopathology due to smn mutations
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Rocha, Carols A. (Carlos Andres Rocha Penagos). "SMPL : a network architecture for collaborative distributed services." Thesis, Massachusetts Institute of Technology, 2005. http://hdl.handle.net/1721.1/33889.
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Thesis (S.M.)--Massachusetts Institute of Technology, School of Architecture and Planning, Program in Media Arts and Sciences, 2005.<br>Includes bibliographical references (p. 85-89).<br>This thesis proposes a network architecture, called SMPL, for the design and development of collaboration-oriented, distributed applications over the Internet. The goal of SMPL is to enable the development of applications that easily integrate the capabilities of different types of computing resources, software platforms, and data repositories across the Internet transcending the level of a single device. SMPL proposes a new abstraction of the Internet as a network composed of services, resources, and capabilities instead of just machines. The SMPL architecture distributes resources through a peer-to-peer network of service providers. The design of SMPL encourages developers to add value to the system by facilitating the creation of new functionalities based upon compositions of the existing ones.<br>Carlos A. Rocha.<br>S.M.
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Herrada, B. Patricio, and F. Claudio Rojas. "Plan estratégico de marketing: servicio intradomiciliario SMAPA-HOGAR." Tesis, Universidad de Chile, 2005. http://www.repositorio.uchile.cl/handle/2250/111207.
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Tesis para optar al grado de Magíster en Administración<br>No disponible a texto completo<br>Los servicios sanitarios constituyen prestaciones básicas vinculadas al bienestar social, por cuanto desempeñan un papel fundamental para la salud de las personas y el adecuado desarrollo de las actividades productivas del país.
En 1989 se realizó una reestructuración completa de la industria sanitaria, la cual contempló la creación de varios cuerpos legales complementarios; La Ley General de Servicios Sanitarios (DFL N°382), que definió las reglas para solicitar y otorgar las concesiones de servicios sanitarios y las condiciones para su explotación. El DFL Nº 70, que fijó las normas para determinar las tarifas de cada empresa concesionaria bajo criterios de eficiencia económica y autosuficiencia financiera, y la Ley 18.902, que creó la Superintendencia de Servicios Sanitarios fijando su estructura y atribuciones. En estos años también se promulgó la ley sobre subsidios al consumo de agua potable.
A partir de la creación de las empresas en el año 1989, éstas iniciaron un proceso de “empresarización”, orientado a generar incentivos y esquemas de operación de tipo empresarial, lo que evidentemente ha redundado en un aumento de la eficiencia y productividad de las mismas.
En términos generales se puede sostener que las empresas sanitarias operan bajo concesiones otorgadas por el Estado, lo que las compromete a entregar servicio a toda persona dentro de su área de concesión. El operador tiene derecho a explotar dicha concesión por un período de tiempo indefinido y cobrar a sus clientes por los servicios brindados.
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Pablos, Hernández Miriam. "Earth remote sensing with SMOS, Aquarius and SMAP missions." Doctoral thesis, Universitat Politècnica de Catalunya, 2016. http://hdl.handle.net/10803/403991.
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The first three of a series of new generation satellites operating at L-band microwave frequencies have been launch in the last decade. L-band is particularly sensitive to the presence of water content in the scene under observation, being considered the optimal bandwidth for measuring the Earth's global surface soil moisture (SM) over land and sea surface salinity (SSS) over oceans.
Monitoring these two essential climate variables is needed to further improve our understanding of the Earth's water and energy cycles. Additionally, remote sensing at L-band has been proved useful for monitoring the stability in ice sheets and measuring sea ice thickness.
The ESA's Soil Moisture and Ocean Salinity (SMOS, 2009-2017) is the first mission specifically launched to monitor SM and SSS. It carries on-board a novel synthetic aperture radiometer with multi-angular and full-polarization capabilities. NASA's Aquarius (2011-2015) was the second mission, devoted to SSS monitoring with a combined real aperture radiometer/scatterometer system
that allows correcting for sea surface roughness. NASA's Soil Moisture Active Passive (SMAP, 2015-2018) is the second mission dedicated to measure SM. It carries on-board a real aperture full-polarimetric radiometer and a synthetic aperture radar (SAR) for enhanced spatial resolution and freeze/thaw detection.
This Ph.D. Thesis is focused on analyzing the geophysical information that can be obtained from L-band SMOS, Aquarius and SMAP observations. The research activities are structured as follows: -Inter-comparison of radiometer brightness temperatures at selected targets. A novel methodology to measure the consistency between SMOS and Aquarius radiometric data over the entire dynamic range of observations (land, ice and ocean) is proposed. It allows detecting spatial/temporal differences or biases without latitudinal limitations neither cross-overs. This is a necessary step to combine observations from different instruments in a long term dataset for environmental, meteorological, hydrological or climatological studies.
-Ice thickness effects on passive remote sensing of Antarctic continental ice. The relationship between Antarctic ice thickness spatial variations and changes detected by SMOS and Aquarius measurements is explored. The emissivity of Antarctica is analyzed to disentangle the role of the geophysical contributions (snow layers at different depths and subglacial lakes) to the observed signal.
The stability of the L-band signal in the East Antarctic Plateau, calibration/validation site for microwave satellite missions, is assessed.
-Microwave/optical synergy for multi-scale soil moisture sensing. The relationship of SM and land surface temperature (LST) dynamics is evaluated to better understand the fundamental SM-LST link through evapotranspiration and thermal inertia physical processes. A new approach to measure the critical soil moisture from time-series of spaceborne SM and LST is proposed. The synergistic use of SMOS SM and remotely sensed LST for refining SM disaggregation algorithms is also analyzed.
-Comparison of passive and active microwave vegetation parameters. Recent research has shown that microwave vegetation opacity, sensitive to biomass and water content, and albedo, related to canopy structure, can be retrieved from passive L-band observations. The relationships between these two parameters and radar-derived vegetation descriptors have been explored using
airborne observations from the SMAP Validation Experiment 2012 (SMAPVEX12). The obtained relations could allow for improved SM retrievals in active-passive systems, and also to estimate the vegetation properties at high resolution using SAR observations.
The Ph.D. Thesis has been developed within the activities of the Barcelona Expert Centre (BEC). The presented results contribute to the use of L-band remote sensing in different scientific disciplines such as climate, cryosphere, hydrology and ecology.<br>Els primers tres d'una sèrie de satèl·lits de nova generació funcionant a la banda L han sigut llançats a l'última dècada. La banda L es molt sensible a la presència d'aigua a l'escena observada, sent considerada òptima per mesurar la humitat del sòl (SM) i la salinitat del mar (SSS) de manera global a la superfície de la Terra. Monitoritzar aquestes dues variables climàtiques essencials es necessari per millorar el nostre coneixement dels cicles de l'aigua i l'energia. La teledetecció a banda L també ha sigut útil per monitoritzar l'estabilitat de les capes de gel i mesurar el gruix de gel marí. La missió Soil Moisture and Ocean Salinity (SMOS, 2009-2017) de l'ESA és la primera específicament llançada per monitoritzar SM i SSS. Porta un nou radiòmetre d'apertura sintètica amb capacitat multiangular i polarització completa. La missió Aquarius (2011-2015) de la NASA va ser la segona, dedicada a monitoritzar SSS amb un sistema de radiòmetre/escateròmetre d’apertura real que permet corregir la rugositat de la superfície del mar. La missió Soil Moisture Active Passive (SMAP, 2015-2018) de la NASA és la segona dedicada a mesurar SM. Porta un radiòmetre d'apertura real i polarització completa i un radar d'apertura sintètica (SAR) per una millor resolució espaial i detecció de congelació/descongelació. Aquesta tesi està enfocada en analitzar la informació geofísica que pot obtenir-se de les observacions a banda L d'SMOS, Aquarius i SMAP. La seva investigació està estructurada com: -Intercomparació de temperatures de brillantor en zones seleccionades. Es proposa un nou mètode per mesurar la consistència entre les dades radiomètriques d'SMOS i Aquarius sobre el rang dinàmic complet d'observacions (terra, gel, oceà). Això permet detectar diferències espaials/temporals o biaixos sense limitacions latitudinals ni creuaments. Aquest pas es necessari per combinar observacions de diferents instruments en un llarg conjunt de dades per estudis mediambientals, hidrològics o climatològics. -Efecte de gruix de gel en teledetecció de gel continental a l'Antàrtida. S'explora la relació entre les variacions espaials del gruix de gel antàrtic i els canvis detectats a les mesures d'SMOS i Aquarius. L'emissivitat de l'Antàrtida es analitzada per discernir el rol de les contribucions geofísiques (capes de gel a diferents profunditats i llacs subglacials) al senyal observat. S'avalua l'estabilitat del senyal a banda L sobre la zona est de l'altiplà antàrtic, lloc per calibratge/validació de satèl·lits de microones. -Sinèrgia de microones/òptic per teledetecció de SM multiescala. S'avalua la correlació entre la SM i la temperatura de la superfície del sòl (LST) per entendre millor la relació SM-LST a través de processos físics d'evapotranspiració i inèrcia tèrmica. Es proposa un nou mètode per mesurar la humitat crítica utilitzant sèries temporals de SM i LST de satèl·lit. S'analitza l'ús de la SM de SMOS amb la LST de teledetecció per refinar algorismes de desagregació de SM. -Comparació de paràmetres passius i actius de microones relatius a la vegetació. Recent investigació ha mostrat que l'opacitat, sensible a la biomassa i el contingut d'aigua, i l'albedo, relacionat amb l'estructura, poden ser recuperats d'observacions passives a banda L. S'exploren les relacions entre aquests dos paràmetres i estimadors de vegetació derivats de radar utilitzant les observacions d'avió de l'experiment de validació d'SMAP 2012 (SMAPVEX12). Les relacions obtingudes podrien permetre millors recuperacions de SM en sistemes actius/passius i estimar les propietats de la vegetació a alta resolució utilitzant mesures de SAR. La tesi s'ha desenvolupat dins les activitats del Barcelona Expert Centre (BEC). Els resultats presentats contribueixen a l'ús de la banda L a diferents disciplines científiques com la climatologia, la criosfera, la hidrologia i l'ecologia.
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Robinson, Andrea Keryn. "Microbial zinc metallothioneins : function of SmtA and species distribution." Thesis, University of Newcastle Upon Tyne, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.366622.
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Tareen, Maria. "Investigating copper binding to bacterial metallothioneins SmtA and MymT." Thesis, University of Warwick, 2014. http://wrap.warwick.ac.uk/66365/.
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Metallothioneins are characterized as a group of small proteins with low molecular weight and high content of cysteinyl residues and their synthesis is induced by metal ions (e.g., Zn or Cd). The physicochemical properties of Zn-, Cd-, and Cu-containing MTs have been studied. However, copper metallothioneins (CuOMTs) have been examined less intensively, with only two MTs containing Cu(I) having been structurally characterized to date i.e., yeast MT and Neurospora crassa MT. The present study focuses on the stoichiometry and structural effects of binding of Cu(I) to the natively zinc binding MT (SmtA) from the cyanobacterium Synechococcus elongatus PCC7942. For this purpose, a Cu(I) titration study of Zn4SmtA was anaerobically performed utilizing the collective detection of ESIOMS, UV-Vis absorbance and 1H-15N NMR spectroscopy, and fully exchanged Cu(I)-SmtA was also generated from the apoOprotein. ESIOMS data confirmed the presence of predominantly monomeric Cu7SmtA. UV-vis titrations of Zn4SmtA showed that up to 7 Cu(I) displace Zn(II) from the protein, which was further studied in more detail by Cu(I) titrations of Zn4SmtA monitored with 1H-15N and 111Cd-15H NMR spectroscopy. The extensive NMR analysis showed the unfolding of protein on Cu(I) addition with absence of inertness towards Cu(I) exchange and that the protein undergoes significant conformational changes on Cu(I) addition. Preliminary characterization of MymT from Mycobacterium tuberculosis was also done and the composition of the metal cluster in the dominant Cu5MymT species was proposed and cooperativity was established by ESIOMS analyses, although structural characterisation was impeded by the highly dynamic nature of the protein.
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Chew, W. M. "Optimum electromagnetic design for wound components in SMPS applications." Thesis, University of Bath, 1989. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.328339.
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Schmollinger, Martin. "Designing parallel algorithms for SMP clusters." [S.l. : s.n.], 2003. http://deposit.ddb.de/cgi-bin/dokserv?idn=969343841.
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Puttmann, John Paul. "Spatially Targeted Activation of a SMP." University of Dayton / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1525166147319011.
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Kolář, Jan. "Motivace pracovníků ve firmě SMP CZ." Master's thesis, Vysoká škola ekonomická v Praze, 2011. http://www.nusl.cz/ntk/nusl-81623.
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The aim of this master thesis is an analysis of a motivation system in SMP CZ. The first part defines the way of a research and describes used methods. The second part focuses on theoretical knowledge, which is crucial for understanding of motivation. The biggest part is devoted to actual research of a job satisfaction of employees. In this context, possible solutions and perspectives for future development are suggested.
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Buchanan, Matthew L. "Investigation of Advanced Spaceborne GNSS-R Techniques Usingthe SMAP Satellite." The Ohio State University, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=osu1565890319858178.
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Pachalla, Seshadri Rajagopal. "Analysis of oscillating flow cooled SMA actuator." Texas A&M University, 2004. http://hdl.handle.net/1969.1/2669.
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Shape Memory Alloys (SMA) are a group of metallic alloys that have the ability to return to some previously defined shape or size when subjected to an appropriate thermal cycling procedure. In recent years there has been a lot of research on the development of small, light and, yet, powerful actuators for use in areas like robotics, prosthetics, biomimetics, shape control and grippers. Many of the miniaturized conventional actuators do not have sufficient power output to be useful and SMAs can be used advantageously here.
The widespread use of SMAs in actuators is limited by their low bandwidth. Use of SMAs in two-way actuators requires that they undergo thermal cycling (heating and cooling). While SMAs can be heated quickly by resistive heating, conventional convection cooling mechanisms are much slower as the exothermic austenitic to martensitic phase transformation is accompanied by the release of significant amount of latent heat.
While a number of cooling mechanisms have been studied in SMA actuator literature, most of the cooling mechanisms involve unidirectional forced convection. This may not be the most effective method. Oscillating flow in a channel can sometimes enhance heat transfer over a unidirectional flow. One possible explanation for this heat transfer enhancement is that the oscillatory flow creates a very thin Stokes viscous boundary-layer and hence a large time-dependent transverse temperature gradient at the heated wall. Therefore heat transfer takes place at a large temperature difference, thereby enhancing the heat transfer.
In this work, the heat transfer from an SMA actuator under an oscillating channel is investigated and is compared to steady, unidirectional flow heat transfer.
Oscillating flow is simulated using a finite volume based method. The resulting velocity field is made use of in solving the heat transfer problem using a finite difference scheme. A parametric study is undertaken to identify the optimal flow conditions required to produce the maximum output for a given geometry of the SMA actuator. The latent heat of transformation of the SMA is accounted for by means of a temperature dependent specific heat.
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Martin, Michael Paul. "Performance measurement in the RAMP SMP facility." Thesis, Monterey, California. Naval Postgraduate School, 1989. http://hdl.handle.net/10945/26157.
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Dano, Marie-Laure. "SMA-Induced Deformations In general Unsymmetric Laminates." Diss., Virginia Tech, 1997. http://hdl.handle.net/10919/30390.
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General unsymmetric laminates exhibit large natural curvatures at room temperature. Additionally, inherent to most unsymmetric laminates is the presence of two stable configurations. Multiple configurations and stability issues arise because of the geometric nonlinearities associated with the large curvatures. The laminate can be changed from one stable configuration to the other by a simple snap-through action. This situation offers the opportunity to use shape memory alloys (SMA) attached to the laminate to generate the snap-through forces and change the shape of the laminate on command. Presented is a model which can predict SMA-induced deformations in general unsymmetric laminates and, particularly, the occurrence of the snap through. First, a methodology is developed to predict the deformations of flat general unsymmetric epoxy-matrix composite laminates as they are cooled from their elevated cure temperature. Approximations to the strain fields are used in the expression for the total potential energy, and the Rayleigh-Ritz approach is used to study equilibrium. To further study the laminate deformations, finite-element analyses are performed. Experimental results are presented which confirm the predictions of the developed theory and the finite-element analyses regarding the existence of multiple solutions and the magnitude of the deformations. Results are compared with those of several other investigators. Next, the deformation behavior of general unsymmetric laminates subjected to applied forces is studied. The principle of virtual work is used to derive the equilibrium equations relating the laminate deformations to the applied forces. By solving the equilibrium equations as a function of the force level, relations between the laminate deformations and the applied force are derived, and the force level at which the laminate changes shape is determined. Finally, an existing SMA constitutive model is implemented into the developed theory to predict the deformations of simple structures to SMA-induced forces. Experiments on a narrow aluminium plate with an externally attached SMA actuator are conducted. The experimental results show good agreement with the predictions from the developed theory. Next, the deformation behavior of general unsymmetric laminates subjected to SMA actuators is predicted using the developed theory. Experiments using SMA actuators to generate the snap through of nsymmetric laminates are conducted. Good correlation with the developed theory is obtained.<br>Ph. D.
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Anjum, Sadaf Saad. "Fabrication of smart intercalated polymer-SMA nanocomposite." Thesis, Cranfield University, 2015. http://dspace.lib.cranfield.ac.uk/handle/1826/9384.
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Mimicking nature gives rise to many important facets of biomaterials. This study is inspired by nature and reports on the fabrication of an intercalated polymer-NiTi nanocomposite that mimics the structural order of urethral tissue performing micturition. PTFE is chosen due to its hydrophobicity, low surface energy, and thermal and chemical stability. NiTi has been selected as a prime candidate for this research due to its excellent mechanical stability, corrosion resistance, energy absorbance, shape memory and biocompatibility. Nanoscale engineering of intercalated nanocomposites is done by PVD sputtering PTFE and NiTi. FTIR spectroscopy confirms that PTFE reforms as polymer chains after sputtering. Suitable PVD sputtering parameters were selected by investigating their influence on deposition rates, microstructure and properties of PTFE and NiTi thin films. PTFE forms stable nanocomposite coatings with NiTi and displays favourable surface interactions, known as ‘intercalation’. Intercalated PTFE-NiTi films were fabricated as layered and co-sputtered thin films. Co-sputtered nanocomposites contained nearly one-third vacant sites within its internal microstructure because of intercalation while intercalation introduced minute pits in fibrous NiTi columns of layered nanocomposites. These pits allow PTFE to extend their chains and crosslinks, resulting in microstructural and functional changes in the thin films. Intercalated PTFE-NiTi nanocomposites offer a close match to the natural tissue in terms of responding to the fluid contact (wetting angle modifications), and allow the soft and hard matter to incorporate in one framework without any chemical reactions (intercalation). An intercalated microstructure in co-sputtered and layered nanocomposites was verified by EDS-SEM and EDS-TEM techniques. The functional responses were witnessed by changes in water contact angle (WCA) and coefficient of friction (CoF) values measured on the film surface. The WCA (99°) and CoF (0.1 – 0.2) of the intercalated nanocomposite (sample PNT12) were different to the NiTi (top layer). WCA and CoF indicate the internal microstructural interactions because of intercalation. Although the pseudoelastic behaviour of NiTi can provide additional fluid response but the difficulty is an absence of crystallinity in as-deposited NiTi, and the heat treatment that melts PTFE. However, DSC and XRD techniques were employed to find the optimum NiTi composition and transition temperatures for phase transformation related to pseudoelasticity. This study provides the basis to incorporate the shape memory (pseudoelasticity or thermal shape memory effect (shape memory effect)) features of NiTi into the intercalated nanocomposite in future. The intercalated PTFE-NiTi nanocomposite reveals a fascinating research precinct, having the response generating characteristics similar to that of natural tissue.
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Chen, Yen-Ming. "RC Snubber Design using Root-Loci Approach for Synchronous Buck SMPS." Thesis, University of Waterloo, 2005. http://hdl.handle.net/10012/963.
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This thesis presents an analytical approach using Root-Loci method for designing optimum passive series RC snubbers for continuous-current synchronous buck switch mode power supply (SMPS).
Synchronous buck SMPS is the most popular power converter topology found in modern consumer electronics. It offers relatively good efficiency to target the high-current and low-voltage requirements while it is also relatively inexpensive to implement.
Passive series RC snubbers are simple, efficient and cost-effective open-loop equalizer circuit for synchronous buck SMPS. Its purpose is to control and to balance between the rate of rise and the overshoots of transient switching waveform in order to optimize efficiency and reliability
Existing methods of RC snubber design are solely based on second-order approximation. It is investigated in this research that this approximation is highly inaccurate in SMPS applications because higher order equivalent models are required for the load path of the SMPS. The results using the RC snubbers obtained from existing method are shown to be unsatisfactory without correlation to the calculations and simulations based on second-order approximation. Optimum RC values obtained using Root-Loci approach presented in this thesis are shown to correlate to both Spice simulation and lab measurements.
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Miller, Mickey R. "The Role of SmpB in Licensing tmRNA Entry into Stalled Ribosomes." BYU ScholarsArchive, 2013. https://scholarsarchive.byu.edu/etd/4162.
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Ribosomes translate the genetic information contained in mRNAs into protein by linking together amino acids with the help of aminoacyl-tRNAs. In bacteria, protein synthesis stalls when the ribosome reaches the 3'-end of truncated mRNA transcripts lacking a stop codon. Trans-translation is a conserved bacterial quality control process that rescues stalled ribosomes. Transfer-messenger RNA (tmRNA) and its protein partner SmpB mimic a tRNA by entering the A site of the ribosome and accepting the growing peptide chain. The ribosome releases the truncated mRNA and resumes translation on the tmRNA template. The open reading frame found on tmRNA encodes a peptide tag that marks the defective nascent peptide for proteolysis. A stop codon at the end of the open reading frame allows the ribosome to be recycled and engage in future rounds of translation.The entry of tmRNA into stalled ribosomes presents a challenge to our understanding of ribosome function because during the canonical decoding process, the ribosome specifically recognizes the codon-anticodon duplex formed between tRNA and mRNA in the A site. Recognition of proper base-pairing leads to conformational changes that accelerate GTP hydrolysis by EF-Tu and rapid accommodation of the tRNA into the ribosome for peptidyl transfer. The puzzle is that tmRNA enters stalled ribosomes and reacts with the nascent peptide in the absence of a codon-anticodon interaction. Instead, SmpB binding in the decoding center begins the rescue process, but it has been unclear how SmpB licenses tmRNA entry into stalled ribosomes. We analyzed a series of SmpB and ribosomal RNA mutants using pre-steady-state kinetic assays for EF-Tu activation and peptidyl transfer. Although the conserved 16S nucleotides A1492 and A1493 play an essential role in canonical decoding, they play little or no role in EF-Tu activation or peptidyl transfer to tmRNA. In contrast, a third nucleotide, G530, stacks with the side chain of SmpB residue His136, inducing conformational changes that lead to GTP hydrolysis by EF-Tu. A portion of the C-terminal tail forms a helix within the mRNA channel, monitoring the length of mRNA bound in the ribosome to avoid aborting productive protein synthesis. Helix formation in the mRNA channel is essential for accommodation and peptidyl transfer, but not for GTP hydrolysis. We show that conserved residues in the tail are essential for EF-Tu activation, accommodation, or translocation to the P site. Our findings lead to a clearer model of how the tmRNA-SmpB complex enters stalled ribosomes.
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Cazier, DeAnna June. "The Role of SmpB in the Early Stages of Trans-Translation." BYU ScholarsArchive, 2009. https://scholarsarchive.byu.edu/etd/2126.
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Ribosomes stall on defective messenger RNA transcripts in eubacteria. Without a mechanism to release stalled ribosomes, these cells would die. Transfer-messenger RNA (tmRNA) and small protein B (SmpB) reactivate stalled ribosomes in a process known as trans-translation. Together, tmRNA and SmpB mimic alanyl-tRNA, entering the A site of stalled ribosomes and accepting transfer of the stalled polypeptide. A portion of tmRNA is then positioned as a template for the ribosome to resume translating. The tmRNA open reading frame encodes a proteolysis tag to mark the aberrant polypeptide for degradation and a stop codon to release the ribosome. How are tmRNA and SmpB allowed into stalled ribosomes? In normal translation, decoding mechanisms carefully monitor the anticodon of tRNAs entering the A site and select only those that are complementary to the mRNA codon. How do tmRNA and SmpB get around the decoding machinery? It appears that interactions between the SmpB C-terminal tail and the decoding center are responsible. Using an in vivo tagging assay and an in vitro peptidyl-transfer assay, we monitored the effect of mutations in the SmpB tail on trans-translation. We found that mutations in SmpB that prevent helix formation are unable to support peptidyl transfer. We also found that while mutation of key nucleotides in the ribosomal decoding center severely inhibit peptidyl transfer to normal tRNAs, these mutations do not inhibit peptidyl transfer to tmRNA. We conclude that the SmpB tail stimulates peptidyl transfer by forming a helix that interacts with the ribosome to signal decoding in a novel manner. How is the tmRNA open reading frame positioned for the ribosome to resume translating? Mutation of the tmRNA nucleotide A86 alters reading frame selection. Using a genetic selection, we identified SmpB mutants that restore normal frame selection to A86C tmRNA without altering frame selection on wild-type tmRNA. Through rational mutation of the SmpB tail we identified an SmpB mutant that supports peptidyl transfer but prevents translation of the tmRNA open reading frame. We conclude that SmpB plays a functional role in selecting the tmRNA open reading frame.
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Hippold, Judith, and Gudula Rünger. "Task Pool Teams for Implementing Irregular Algorithms on Clusters of SMPs." Universitätsbibliothek Chemnitz, 2006. http://nbn-resolving.de/urn:nbn:de:swb:ch1-200600537.
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The characteristics of irregular algorithms make a parallel implementation difficult, especially for PC clusters or clusters of SMPs. These characteristics may include an unpredictable access behavior to dynamically changing data structures or strong irregular coupling of computations. Problems are an unknown load distribution and expensive irregular communication patterns for data accesses and redistributions. Thus the parallel implementation of irregular algorithms on distributed memory machines and clusters requires a special organizational mechanism for a dynamic load balance while keeping the communication and administration overhead low. We propose task pool teams for implementing irregular algorithms on clusters of PCs or SMPs. A task pool team combines multithreaded programming using task pools on single nodes with explicit message passing between different nodes. The dynamic load balance mechanism of task pools is generalized to a dynamic load balance scheme for all distributed nodes. We have implemented and compared several versions for task pool teams. As application example, we use the hierarchical radiosity algorithm, which is based on dynamically growing quadtree data structures annotated by varying interaction lists expressing the irregular coupling between the quadtrees. Experiments are performed on a PC cluster and a cluster of SMPs.
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Henriques, Moreira Daniel. "SimPatrol: um simulador de sistemas multiagentes para o patrulhamento." Universidade Federal de Pernambuco, 2008. https://repositorio.ufpe.br/handle/123456789/2248.
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Made available in DSpace on 2014-06-12T15:55:45Z (GMT). No. of bitstreams: 2
arquivo2286_1.pdf: 1818614 bytes, checksum: bde38ef39500718996aa2511dab57905 (MD5)
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Previous issue date: 2008<br>Conselho Nacional de Desenvolvimento Científico e Tecnológico<br>Apesar de sistemas multiagentes estarem se tornando cada vez mais comuns no
desenvolvimento de software, há ainda que se chegar a um consenso sobre como
modelar e comparar diferentes soluções de sistemas multiagentes para um mesmo
problema. Em outras palavras, os pesquisadores de tal área ainda estão à procura
de benchmarks que sirvam de referência para a comparação de abordagens
distintas. Dada a importância do estabelecimento de benchmarks para sistemas
multiagentes, uma questão que surge entre os pesquisadores da área de
patrulhamento é a possibilidade e o potencial do problema do patrulhamento como
um destes benchmarks. Apesar da quantidade de trabalho produzido até este ponto,
tem-se encontrado dificuldades para comparar precisamente as soluções propostas
para o patrulhamento. Estas dificuldades remetem principalmente à ausência de
ferramentas (em especial um simulador unificado) que permitam aos estudiosos se
concentrarem na solução do problema em si, e não na sua representação. Partindo
deste cenário, este trabalho tem como objetivo discutir o estabelecimento do
patrulhamento enquanto um benchmark para sistemas multiagentes.
Adicionalmente, como um primeiro passo no sentido de preencher as lacunas que
dificultam tal estabelecimento, introduz-se o SimPatrol, um novo simulador voltado
para a tarefa de patrulhamento, fortemente inspirado pelos simuladores da RoboCup
e TAC. Novos resultados são produzidos a partir de uma avaliação de parte das
técnicas propostas pelas pesquisas anteriores frente às novas funcionalidades
implementadas pelo simulador, em especial a inédita medida de ociosidade dos
vértices, que leva em consideração o tempo de raciocínio gasto pelos patrulheiros
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Paredes, Matta Elizabeth Victoria Adela. "Comportamiento mecánico de las mezclas tipo SMA (STONE MASTIC ASPHALT)." Bachelor's thesis, Universidad Ricardo Palma. Programa Cybertesis PERÚ, 2010. http://cybertesis.urp.edu.pe/urp/2010/paredes_ev/html/index-frames.html.
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Pardon, Gaspard. "A feasibility Study of SMA Powder Composite Actuators." Thesis, KTH, Mikrosystemteknik, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-91283.
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黃君保 and Kwan-po Wong. "High-speed network interface for commodity SMP clusters." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2000. http://hub.hku.hk/bib/B31225330.
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Wong, Kwan-po. "High-speed network interface for commodity SMP clusters." Hong Kong : University of Hong Kong, 2000. http://sunzi.lib.hku.hk/hkuto/record.jsp?B22505520.
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Dano, Marie-Laure. "SMA-induced deformations in unsymmetric cross-ply laminates." Thesis, This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-09122009-040504/.
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Aphanuphong, Sutha. "Embedded heaters and sensors for micro SMA actuators." Connect to online resource, 2008. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1458441.
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Acuna, Subia Luis Carlos. "Vlastnosti asfaltových směsí typu SMA s R-materiálem." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2018. http://www.nusl.cz/ntk/nusl-371816.
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The aim of the diploma thesis is to verify and compare the properties of bituminous stone mastic asphalt, namely SMA 11S with modified PMB 45 / 80-55 asphalt binder or 50/70 road bitumen binder with rubber granulate. Comparison of properties is performed using functional tests. The thesis is divided into the theoretical and practical part. The theoretical part deals with the familiarization with the use of the SMA mixture, the selected concepts concerning recycling of non-leveled roads are described and described. Attention is paid especially to the recycling of roads in the Czech Republic with an emphasis on hot recycling on the incinerator, which allows increased dosing of Reclaimed Asphalt into asphalt mixtures. In the practical part, the results of the functional tests of the SMA 11S mixture, which have been taken from the test section, are processed and evaluated.
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Aghamaleky, Sarvestany Arwin. "Schwann cell pathology in spinal muscular atrophy (SMA)." Thesis, University of Edinburgh, 2015. http://hdl.handle.net/1842/15908.
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The childhood neuromuscular disease spinal muscular atrophy (SMA) is caused by low levels of survival motor neuron (SMN) protein. Historically, SMA has been characterised as a disease primarily affecting lower motor neurons. However, recent breakthroughs have revealed defects in other non-neuronal cells and tissues. In vivo analysis of peripheral nerve showed defects in Schwann cells, manifesting as abnormal myelination and delayed maturation of axo-glia interactions. The experiments in this thesis were designed to build on these observations and examine whether Schwann cell defects are intrinsic and occur as a primary result of low levels of SMN in that cell type, or rather represent a secondary consequence of pathology in neighbouring motor neurons. I initially developed a protocol to allow isolation of high-yields of purified, myelination-competent Schwann cells from ‘Taiwanese’ SMA mice. SMA-derived Schwann cells had significantly reduced SMN levels and failed to respond normally to differentiation cues. Increasing SMN levels restored myelin protein expression in Schwann cells from SMA mice. Perturbations in expression of key myelin proteins were likely due to failure of protein translation and/or stability rather than transcriptional defects. Co-cultures of healthy neurons with SMA Schwann cells revealed a significant reduction in myelination compared to cultures where wild-type Schwann cells were used. The presence of SMA Schwann cells also disrupted neurite stability. Perturbations in the expression of key extracellular matrix proteins, such as laminin α2, in SMA-derived Schwann cells suggests that Schwann cells were influencing neurite stability by modulating the composition of the extracellular matrix. Previous studies have demonstrated that low levels of SMN lead to disruption of ubiquitin homeostasis and decreased expression of ubiquitin-like modifier activating enzyme (UBA1) in the neuromuscular system, driving neuromuscular pathology via a beta-catenin dependent pathway. Label-free proteomics analysis of SMA and control Schwann cells identified 195 proteins with modified expression profiles. Bioinformatic analysis of these proteins using Ingenuity Pathway Analysis (IPA) software confirmed that major disruption of protein ubiquitination pathways was also present in Schwann cells from SMA mice. Immunolabeling and proteomics data both revealed that UBA1 levels were significantly reduced in SMA-derived Schwann cells. However, loss of UBA1 in Schwann cells did not lead to downstream modifications in beta-catenin pathways. Pharmacological inhibition of UBA1 in healthy Schwann cells was sufficient to induce defects in myelin protein expression, suggesting that UBA1 defects contribute directly to Schwann cell disruption in SMA. I conclude that low levels of SMN induce intrinsic defects in Schwann cells, mediated at least in part through disruption to ubiquitination pathways.
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Watts, Talina Christensen. "Genetic analysis of the role of SmpB in determining frame on tmRNA /." Diss., CLICK HERE for online access, 2008. http://contentdm.lib.byu.edu/ETD/image/etd2501.pdf.
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Carretero, Miguel Adrian. "Aplicação dos conceitos do SMP2 para comunicação entre sistemas legados de simulação." Instituto Nacional de Pesquisas Espaciais, 2012. http://urlib.net/sid.inpe.br/mtc-m19/2011/12.05.20.15.
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Um Simulador de Satélites é composto por modelos que representam o comportamento dos vários subsistemas de um satélite podendo ainda, incluir modelo do ambiente espacial e de estações terrenas de recepção de dados. Muitos destes modelos, em especial os do ambiente espacial, geralmente, não sofrem alterações de um simulador para outro, podendo ser reutilizados ao longo de anos, em diferentes simuladores. Entretanto, esta prática de reutilização não tem sido rotineiramente aplicada. Visando melhorar a interoperabilidade e aumentar o reúso neste tipo de aplicação, a Agência Espacial Européia (ESA) definiu o padrão Simulation Model Portability (SMP), Portabilidade de Modelos de Simulação, que orienta a estruturação de Simuladores de Satélite. O objetivo dessa dissertação é explorar a aplicabilidade dos conceitos do SMP para viabilizar a comunicação entre modelos legados de simulação. Identificados os limites na arquitetura atual do SMP foi proposta uma extensão aos mecanismos de comunicação desta arquitetura de modo a permitir a inclusão dos modelos legados a um simulador que seja conforme o SMP. Uma demonstração da solução dada ao mecanismo de comunicação proposto é feita através de um estudo de caso. Essa dissertação mostra uma solução para aplicação dos mecanismos para interoperabilidade entre modelos legados de simulação se beneficiando da padronização para reforçar o reúso de modelos e de mecanismos que dão suporte a um simulador. Entretanto, a solução ainda mantém a dependência da plataforma computacional e de uma linguagem orientada a objetos.<br>A Satellite Simulator is composed of a set of models that represents the behavior of the various satellite subsystems. It may also include a model of the space environment and of the ground stations. Many of these models, especially the space environment model do not change from one simulator to another and can be reused over the years. However, this is not a common practice. In order to improve interoperability and increase re-use of the models, the European Space Agency (ESA) created a standard named Simulation Model Portability (SMP) that guides the development of Satellite Simulators. The objective of this work is to explore the applicability of the concepts of SMP to enable communication between legacy simulation models. After identifying limitations in the current SMP architecture it was proposed an extension of the SMP communication mechanisms to allow the addition of legacy models to a SMP simulator. A case study was used to demonstrate the results of the proposed communication mechanism. This work also presents a computational implementation of the interoperability mechanisms between the legacy simulation models (which takes advantage from standardization) to enhance the reuse of models and mechanisms that support a simulator system. However, this solution still preserves its dependence on the computing platform and an on an object-oriented language.
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Hanke, Tomas. "Development of solid matrix-antibody-antigen (SMAA) complexes as multivalent subunit vaccines." Thesis, University of St Andrews, 1994. http://hdl.handle.net/10023/13989.
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In the course of the work presented in this thesis, the construction of solid matrix-antibody-antigen (SMAA) complexes as vaccines was further developed. In particular, it was demonstrated that it is feasible to assemble SMAA complexes using a short oligopeptide tag (Pk) attached to the C-termini of antigens and a Pk tag- specific mAb SV5-P-k. In order to facilitate the purification of recombinant proteins for immunization purposes, a second affinity tag was attached to the antigen N-termini. Initially, the N-terminal tag was 26-kDa-large thrombin-removable glutathione S-transferase (GST), which permitted first-step purification on immobilized glutathione. However, because of problems with protein insolubility and the proteolytical removal of GST from the hybrid proteins, the GST domain was substituted by an N-terminal 12-amino acid-long tag (His) containing an array of 6 histidines. The His tag was small and thus did not require removal prior to immunization, and allowed purification of His-linked proteins on a nickel-affinity column. Moreover, it was possible to preform nickel-affinity chromatography under protein denaturing conditions, which allowed purification of insoluble or aggregated proteins. In addition, novel prokaryotic expression vectors were constructed for a single-cloning-step addition of these N- and C-terminal tags to proteins of interest. These vectors were used to individually express all non-glycosylated products encoded by the simian immunodeficiency virus (SIV) in E. coli. The SIV envelope glycoprotein gp160 with the Pk tag attached to its C-terminus was expressed in insect cells and first-step purified on a lentile lectin column. Following the first purification step on either nickel or lentile columns, all SIV proteins were purified and successfully incorporated into SMAA complexes using anti-Pk tag mAb SV5-P-k. Thus, efficient purification protocols were developed, which purified recombinant proteins via two different affinity tags attached to their N- and C-termini and isolated predominantly full-size proteins. As a stage in achieving the goal of human multivalent vaccines, the SV5-P-k mAb was humanized and is currently being expressed in Chinese hamster ovary cells.
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Akram, Farhan. "Gate driver solutions for high power density SMPS using Silicon Carbide MOSFETs." Thesis, Mittuniversitetet, Institutionen för elektronikkonstruktion, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-41188.
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Discrete silicon carbide (SiC) power devices have unique characteristics that outpace those of silicon (Si) counterparts. The improved physical features have provided better faster switching, greater current densities, lower on-resistance, and temperature performances. However, there is lack of suitable commercial gate drivers that are compatible for high-voltage, and high-speed devices. There has been a great research effort required for the advancement of gate drivers for high voltage SiC transistors. A drive circuit for a SiC MOSFET needs to be optimized in normal operation to give best efficiency and same drive circuit should secure the MOSFET under unsuitable conditions. To ensure the rapid switching of these advanced SiC MOSFETs, a gate driver capable of providing the high current capability is required. In this work, three different high-power-density, high-speed, and high-noise-immunity gate driver modules for 10 kV SiC MOSFET were built and optimized. Double-pulse test was developed for the dynamic characterization of SiC MOSFETs and gate drivers. This setup provided clean measurements of DUT voltage and current under well-defined conditions and correlated to simulation results. Designed gate drivers have thoroughly investigated to test and compare it with our future design. The influential parameters such as dV/dt, dI/dt, and gate driving capability of gate driver were adjusted according to the requirements. The short circuit protection test was performed to check the reliability of driver modules in worst conditions. Furthermore, a DC-DC converter was designed and tested with the advanced gate drivers. The driver modules were tested in designed converter under different load conditions and influential parameters were successfully demonstrated. The driver modules effectively helped in reducing the EMI and switching losses. These designed gate drivers and prototype converter provide all the attractive features and can be widely implemented in industrial applications for energy efficient systems.
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Quenum, José Ghislain. "Conception et éxécution d' interactions dans les SMA [Systèmes multi-agents] : spécialisation et sélection de protocoles génériques." Paris 6, 2005. http://www.theses.fr/2005PA066457.
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Yariz, Kemal Oral. "The Chronicles of X-Linked Spinal Muscular Atrophy: The Linkage, The Gene and The SMN Complex." Scholarly Repository, 2008. http://scholarlyrepository.miami.edu/oa_dissertations/115.
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Spinal Muscular Atrophy (SMA) is an autosomal recessive motor neuron disease. SMA is associated with homozygous mutations in the Survival of Motor Neuron gene I (SMN1). SMN protein does not appear to exist in cells in isolation but associates with several proteins to form a large multi-protein complex. The functions of SMN complex include assembly, metabolism and transport of diverse classes of ribonucleoproteins. X- Linked Spinal Muscular Atrophy is a rare congenital disorder characterized by multiple joint contractures. It is associated with hypotonia, areflexia, chest deformities and congenital joint contractures. A candidate interval was defined for XL-SMA in Xp11.3-Xq11.2 in 1995. The purpose of this study was to refine the XL-SMA gene region and discover the XL-SMA gene. In addition to that, the gene product was investigated to delineate the genotype-phenotype correlation. My studies were focused on single nucleotide polymorphism (SNP) analysis. The candidate gene interval was refined by studying 14 SNPs in the three largest families. This analysis revealed a recombination event which allowed elimination of the NDP gene. Significantly positive LOD scores were obtained from these SNP studies. The exons and exon-intron boundaries of 12 genes were screened. No mutations were found in these genes in affected male samples. In late 2006, UBE1 (Ubiquitin activating enzyme 1) was discovered as the XL-SMA gene. UBE1 protein is responsible for the first step of ubiquitination of proteins in a cell. To investigate a possible common molecular mechanism between SMA and XL-SMA, proteins in the SMN Complex in XL-SMA patient cell lines were studied. SMN and Gemin3 protein levels were found to be consistently lower in XL-SMA patient cell lines (lymphoblasts) compared to healthy cell line. These results imply that there may be a common disease mechanism. To understand if the SMN and Gemin3 RNA levels decrease. RNA expression studies were performed. These studies confirmed that there is no difference of RNA expression of SMN and Gemin3 in XL-SMA cell lines when compared to healthy cell lines. As for UBE1, the same experimental procedure for SMN Complex proteins were repeated with antibodies to UBE1 to determine if there is any decline of UBE1 protein levels in XL-SMA patient cell lines compared to a healthy cell line. There was a decline in protein levels of UBE1 in XL-SMA patients. Two possible models are proposed for a molecular mechanism in XL-SMA: 1) UBE1 involves in degradation of a protein which downregulates SMN Complex (or a protein which stabilizes SMN Complex). When UBE1 is mutated, the protein in question is not degraded and this results in excess downregulation of SMN Complex (maybe via a pathway involving SMN-Gemin3 interaction). 2) UBE1 and UBA6 interact with the proteins of SMN Complex as they monoubiquinate them for different cellular processes. When UBE1 is mutated, UBA6 cannot compensate the deficiency of UBE1, which in turn disrupts normal cellular RNA metabolism required for motor neuron development and survival.
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Miguel-Aliaga, Irene. "Spinal muscular atrophy : of flies, worms and men." Thesis, University of Oxford, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.343478.
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Hariri, Mohammed, and not supplied. "Control of Structures Using SMA Wires and Piezoelectric Patches." RMIT University. Aerospace, Mechanical & Manufacturing Engineering, 2009. http://adt.lib.rmit.edu.au/adt/public/adt-VIT20091001.154507.
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Smart materials and structures systems are increasingly being developed to handle more complex problems. One of the main research schemes is the augmentation of the control authority of the smart actuators used in such systems. The augmentation can be obtained by constructing hybrid and multi- smart materials actuator systems and/or by the optimization of the location and orientation of those actuators. In the first part of this study, the alteration of the natural frequency of composite structures using Nitinol-based Shape Memory Alloy (SMA) wires will be presented using the analyses of strain energy perturbations on a plate. These governing strain equations were solved analytically and numerically to show the effect of point forces acting in a distributive manner and the subsequent effect it has on the plate's stiffness and hence it's natural frequency. In the second part of the thesis, a more complex loading condition is considered to investigate piezoceramic actuator control authority in relation to wing flutter control. The advancement in the application of active material induced-strain actuation such as piezoelectric materials in suppression of structural vibrations drew wide interest in its use for wing flutter control. Higher flutter speed and hence wider operating envelope was achieved by delaying the coalescence of the eigenvalues for plunge and twist modes. . This delay is obtained by adding more strain energy to the system as a result of the activation of the piezoelectric actuators. Most of the studies done were by controlling the plunge/bending motion, where the piezoelectric actuators are bonded longitudinally to produce bending moments. In this study, the control of the pitch/twisting motion was investigated and it showed better control of flutter by using simultaneous multi-actuations compared to single piezo actuations. It was shown that within the scope of the angular orientations of the piezoelectric patches investigated in this study, piezoelectric patches oriented about +150 from the beam's longitudinal ax is resulted in the most optimal piezo-configuration. This was corroborated by both the numerical flutter speed and actuator moment evaluations. In addition, the orientation of the piezoelectric patches was shown to significantly affect the pitch angle of the beam relative to each other. The damping ratio was also investigated and this showed greater instability for piezoelectric patches oriented at negative angles, thus further supporting the finding of the aforementioned optimal orientation of +150. These findings confirmed the dominance of the base (closest to the fixed portion of the beam) piezo when actuated with other piezos.
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Sitnikova, Elena. "Dynamic behaviour of an impact system with SMA restraint." Thesis, University of Aberdeen, 2010. http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=202764.
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The interest in use of SMAs in vibrational systems is stimulated by their ability to dissipate energy and consequently their potential to control the dynamic behaviour of the system. In this thesis nonlinear dynamics of an impact oscillator with one sided motion constraint made of a shape memory alloy (SMA) is investigated. The pseudoelastic behaviour of SMAs is characterized by high non-linear recovery deformations and energy dissipation due to the occurrence of hysteresis. The thermo-mechanical description of the SMA element follows the formulation proposed by Bernardini et al. [1,2]. Extensive numerical investigations into the influence of the forcing parameters, which characterize the intensity of the load acting on the SMA has been carried out. They suggest that the system can exhibit complex dynamic responses, which if appropriately controlled can be used for vibration reduction. The comparison with the equivalent elastic oscillator response has shown that the use of the SMA can significantly change the dynamic response of the system. Whereas low amplitude regimes are not affected by the SMA element, at resonances when the response amplitudes are large, a significant vibration reduction is achieved due to the phase transformation hysteresis loop. Two types of periodic response co-existence is also revealed in these regions. At the same time, in other frequency ranges the existence of additional modes of motion in the pseudoelastic oscillator can cause new large amplitude responses (both periodic and chaotic) to be generated, as well as eliminate some of the co-existing responses. Various bifurcation scenarios are constructed and the influence of the SMA element is discussed. To verify the obtained theoretical predictions, an experimental rig was designed and limited experimental studies have been conducted. The substantial response amplitude reduction at resonances has been captured, as well as the jumps to higher amplitude responses due to the softening behaviour of SMA. The numerical results appeared to be in a good agreement with the experimental data.
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Paine, Jeffrey Steven Nelson. "Multi-functional SMA hybrid composite materials and their applications /." This resource online, 1994. http://scholar.lib.vt.edu/theses/available/etd-06062008-162936/.
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Moreira, Maria Isabel Giusti. "Um modelo de sistema AVA-SMA orientado à legislação." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2017. http://hdl.handle.net/10183/171382.
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Dentro da Educação a Distância (EaD), os softwares de apoio como os Ambientes Virtuais de Aprendizagem (AVA) são considerados recursos que favorecem a comunicação entre os atores envolvidos, permitindo a troca de informação. Atribuir Inteligência Artificial a esses AVAs, utilizando Sistemas Multiagentes (SMA) e uma forma de procurar que os mesmos tenham um bom desempenho e que seus recursos facilitem o processo de aprendizagem. Esse trabalho cont em um estudo sobre os principais AVAs existentes e sobre os métodos alternativos de integração de AVA com SMA. Ao analisar o estado da arte dos AVAs pode-se observar que todos trabalham como ferramentas de auxílio ao aluno, por em nenhum deles trabalha aspectos da gestão da EaD dando suporte aos aspectos relevantes da legislação dessa modalidade. Por esse motivo, essa Tese tem por objetivo a criação de um modelo de integração AVA-SMA que possa tornar o AVA MOODLE capaz de auxiliar os gestores da EaD em suas diferentes tarefas, com base na incorporação, ao mesmo, de um modelo de representação de legislação. Para realizar essa integração do modelo AVA-SMA orientado a Legislação foi desenvolvido um espec co modelo organizacional de Sistema Multiagente. Por m com base em um estudo de caso, ser a realizado simulações para veri car as funcionalidades do Modelo de Sistema AVA-SMA orientado a Legislação, proposto nesta Tese.<br>In Distance Learning (EaD), supporting software such as Virtual Learning Environments (VLE) are considered resources that favor communication between the actors involved, allowing the exchange of information. Assigning Arti cial Intelligence to these VLEs, using Multi-Agent Systems (MAS) is a way of ensuring they have a good performance and that its resources facilitate the learning process. This work contains a study on the major existing VLEs and on alternative methods to integrate VLE with MAS. When analyzing the state of the art of the VLEs it is possible to see that all of them work as aid tools for students, but none of them work on management aspects of distance learning that support the relevant aspects of the legislation for this type of education. Therefore, this thesis aims to create a VLE-MAS integration model that can make the VLE MOODLE able to help distance learning managers in their di erent tasks, based on incorporating a legislation representation model to it. To accomplish this integration of the legislation-oriented VLE-MAS model, a speci c Multi-Agent System organizational model was developed. At last, based on a case study, simulations will be conducted to verify the functionalities of the VLE-MAS System Model oriented to legislation, proposed in this thesis.
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Paine, Jeffrey S. "Multi-functional SMA hybrid composite materials and their applications." Diss., Virginia Tech, 1994. http://hdl.handle.net/10919/38219.
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Shape memory alloy (SMA) materials such as nitinol have unique properties associated with the shape recovery effect and the material’s phase changes that have been used in a variety of actuator and sensing applications. By embedding SMA elements into host composite materials, control or modification of the SMA hybrid composite’s structural properties can be accomplished inservice, thereby increasing the hybrid composite’s structural functionality. Previous studies addressed increasing composite materials’ functionality by enabling in-service control of their dynamic response. Utilizing the SMA’s substantial recovery stress and capacity to dissipate strain energy to increase the hybrid composite’s static functionality is addressed herein. Specific applications for SMA hybrid composites include improving composite material’s impact damage resistance and composite cylinder stress and deflection control.
In stress and deflection control of cylindrical structures, SMA actuators are placed within the composite cylinder to form an active compound cylinder. The active SMA elements can significantly reduce the internal pressure-induced radial dilation and creep so that under severe loading, piston to cylinder tolerances may be maintained. Similar to a conventional metallic compound cylinder, the active compound cylinder also reduces peak cylinder hoop stresses. Hybridizing composites with nitinol improves their impact resistance because of nitinol’s tremendous capacity to absorb impact strain energy through the stress-induced martensitic phase transformation. The amount of impact damage is reduced and the material’s resistance to impact perforation at various velocities is improved. The experimental response of nitinol hybrid composites and the associated mechanics are presented. The unique toughness and resistance to permanent deformation that is a result of the stress-induced martensitic phase transformation enables the nitinol to absorb on the order of 4 times the strain energy of high alloy steel and 16 times that of many graphite/epoxy composites.
In most static applications where SMA elements are used for reinforcement, maintaining the integrity of the interface between the SMA elements and the host polymeric matrix composite material is critical to operation. The relationship between preparation of SMA elements for hybrid composite fabrication and interfacial bond strength is presented to address this issue. The mechanics of interfacial shear failure between SMA element and composite is also presented.<br>Ph. D.
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Ebersson, Joel. "Design och konstruktion av laborationsutrustning till en kraftelektronikkurs." Thesis, Uppsala University, Electricity, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-131542.
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<p>The purpose of this degree project was to build laboratory equipment for a new course in power electronics that starts this autumn 2010 at Uppsala University. The equipment is intended for student labs and it covers the most important areas of the course including rectifying, buck-/boost-converters and PWM-modulation. It is built as one sealed unit where all the electronics are built-in but visible and it has a connection board where students safely can connect the different circuits. The project has advanced from theoretical studies of circuit design, choosing of components and simulations to drawing the printed circuit board (PCB), soldering, case building, final testing and troubleshooting - basically most steps from an early idea to a final product. Measurements on the final product gave about the same results as the earlier simulations of the circuits and the result is overall satisfying.</p><br><p>Syftet med det här examensarbetet var att bygga laborationsutrustning till en ny kurs i kraftelektronik som börjar hösten 2010 på Uppsala Universitet. Utrustningen är avsedd för studentlaborationer och den täcker de viktigaste delarna av kursen inklusive likriktning, buck-/boost-omvandlare och pulsbreddsmodulering (PWM). Laborationsutrustningen är byggd som en sluten enhet där all elektronik är inbyggd men synlig och den har en kopplingsplatta där studenterna säkert kan koppla ihop olika kretsar. Projektet har sträckt sig från teoretiska studier inklusive kretsdesign, komponentval och simuleringar till ritande av kretskortet (PCB-kortet), lödning, byggande av höljet, sluttestning och felsökning - i huvudsak de flesta stegen från en tidig idé till en färdig produkt. Mätningar på den färdiga produkten är ganska lika de tidigare simuleringarna av kretsarna och resultatet är totalt sett tillfredställande.</p>