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1
León, Ramón. « Mecacci, L. (1999). Psicología moderna e postmoderna. Roma - Bari : Editori Laterza, 192 p ». Pontificia Universidad Católica del Perú, 2002. http://repositorio.pucp.edu.pe/index/handle/123456789/100012.
Texte intégralRésumé :
Libro de denso contenido, pero de estilo accesible al lector medianamente informado; obra de pequeño formato y dedicada a temas de amplio alcance: esas son apreciaciones que surgen tras la lectura de Psicología moderna e postmodema.Su autor, Luciano Mecacci, poco conocido en el mundo de habla hispana, es probablemente el más prolífico autor de la psicología italianade nuestros días. Su último libro - posterior al que comentamos,dedicado a los "desastres del psicoanálisis"- , es una ácida pero muybien fundamentada crítica a las ideas de Freud como práctica psicoterapéutica
2
Heissenbüttel, Dietrich. « Italienische Malerei vor Giotto Wandmalerei und Geschichte des Gebiets um Matera (Apulien, Basilicata) bis zur Mitte des 14. Jahrhunderts ; Matera, Laterza, Ginosa, Gravina / ». [S.l. : s.n.], 2000. http://deposit.ddb.de/cgi-bin/dokserv?idn=969392753.
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3
Mòdol, Caballero Guillem. « Gene therapy targeting neuregulins for the treatment of amyotrophic lateral sclerosis ». Doctoral thesis, Universitat Autònoma de Barcelona, 2019. http://hdl.handle.net/10803/667869.
Texte intégralRésumé :
L’esclerosi lateral amiotròfica (ELA) és una malaltia neurodegenerativa devastadora sense cap tractament efectiu disponible. Els mecanismes moleculars involucrats en la mort de les motoneurones (MN) són complexos i inclouen nombroses disfuncions d’aquestes, on les cèl·lules del voltant com els astròcits i la micròglia hi poden contribuir. La Neuregulina 1 (NRG1) és un factor neurotròfic expressat en les MNs i les unions neuromusculars que ajuda en el desenvolupament neuromuscular i axonal i en el seu manteniment. Estudis recens suggereixen un rol crucial de la NRG1 i dels seus receptors ErbB en l’ELA, particularment per la isoforma I (NRG1-I) en el procés de reinnervació colateral, i per la isoforma III (NRG1-III) en la preservació de les MNs, obrint un nou camp per desenvolupar noves teràpies per l’ELA. Tanmateix, per clarificar el rol de la via NRG1-ErbB en la supervivència de les MNs és necessari fer més estudis i així provar la seva eficàcia terapèutica.
En la present tesis, hem avaluat l’efecte terapèutic de la sobreexpressió de la NRG1 en el sistema nerviós central i perifèric. D’aquesta manera, primer van caracteritzar el rol de la NRG1 exògena utilitzant un model in vitro de cultius organotípics de medul·la espinal subjectes a una excitotoxicitat crònica causada per l’àcid DL-threo-β-hydroxaspàrtic. Els nostres resultats mostren que l’addició en el medi de la NRG1 recombinant humana (rhNRG1) va incrementar significativament la supervivència de les MNs a través de l’activació dels receptors ErbB. Aquest efecte va ser bloquejat quan vam afegir el lapatinib, un inhibidor dels ErbB. El tractament amb la rhNRG1 també va reduir la reactivitat microglial superant els efectes causats per l’excitotoxicitat, i va activar la via de supervivència PI3K/AKT, a més de restaurar el flux autofàgic normal en el cultiu. A més a més l’addició de la rhNRG1 al medi va promoure el creixement neurític motor i sensorial.
A continuació vàrem decidir d’utilitzar teràpies gèniques basades en vectors adeno-associats per sobreexpressar la NRG1-I en el múscul esquelètic, i la NRG1-III en la medul·la espinal per preservar les MNs en un model in vivo d’ELA, els ratolins SOD1G93A. Els resultats obtinguts van indicar que ambdues teràpies gèniques van ser capaces de preservar la funció neuromuscular dels músculs de les extremitats, van millorar la locomoció, van incrementar el nombre de MNs supervivents, i van reduir la reactivitat astrocitària i microglial en les femelles SOD1G93A tractades a l’estadi final de la malaltia. A més a més, en la medul·la espinal l’eix NRG1-III/ErbB4 regula l’excitabilitat de la MN a través del transportador KCC2 i redueix l’expressió del marcador de vulnerabilitat de MN MMP-9. La NRG1-I expressada en el múscul esquelètic va senyalitzar amb els receptors ErbB2 i 3 presents en les cèl·lules de Schwann terminals, per promoure reinnervació axonal. Malgrat això, quan vàrem combinar ambdues teràpies gèniques no vam trobar un efecte sinèrgic. Conjuntament, els nostres resultats indiquen que les isoformes de la NRG1 juguen un rol important en la supervivència de les MN i que la sobreexpressió viral pot ser considerada com una nova teràpia per tractar l’ELA.Amyotrophic Lateral Sclerosis (ALS) is a devastating neurodegenerative disorder with no effective treatment currently available. The molecular mechanisms that are involved in the motoneuron (MN) death are complex and include several MN dysfunctions, and contribution of surrounding cells such as microglia and astrocytes. Neuregulin 1 (NRG1) is a neurotrophic factor highly expressed in MNs and neuromuscular junctions that supports axonal and neuromuscular development and maintenance. Recent studies have suggested a crucial role for NRG1 and their ErbB receptors in ALS, particularly for isoform I (NRG1-I) in the collateral reinnervation process, and isoform III (NRG1-III) in the preservation of the MNs, opening a new window for developing novel ALS therapies. However, further studies are needed to clarify the role of the NRG1-ErbB pathway on MN survival and to provide the proof of concept of its therapeutical efficacy. In the present thesis we have evaluated the therapeutic effect of NRG1 overexpression in the central and the peripheral nervous system. For this purpose, we first characterized the role of exogenous NRG1 using an in vitro model of spinal cord organotypic cultures (SCOC) subject to chronic excitotoxicity caused by DL-threo-β-hydroxyaspartic acid. Our results revealed that addition of recombinant human NRG1 (rhNRG1) to the medium significantly increased MN survival through the activation of ErbB receptors, which was blocked by addition of lapatinib, an ErbB inhibitor, and reduced microglial reactivity overcoming the excitotoxicity effects. rhNRG1 activated the pro-survival PI3K/AKT pathway and restored the autophagic flux in the spinal cord culture. Furthermore, addition of rhNRG1 to the medium promoted motor and sensory neurite outgrowth. We have then directed gene therapies based on adeno-associated viruses to overexpress NRG1-I in the skeletal muscles, and NRG1-III in the spinal cord to preserve the MNs in the in vivo model of ALS, the SOD1G93A mice. Our results indicate that both gene therapies were able to preserve the neuromuscular function of the hindlimb muscles, improve the locomotor performance, increase the number of surviving MNs and reduce the astrocyte and microglial reactivity in the treated female SOD1G93A mice at the end-stage of the disease. Furthermore, in the spinal cord the NRG1-III/ErbB4 axis regulates MN excitability through the KCC2 transporter and reduces the expression of the MN vulnerability marker MMP-9. NRG1-I expressed in the skeletal muscle signals with ErbB2 and 3 receptors present in terminal Schwann cells to promote axonal reinnervation. However, when we aimed to combine both viral-mediated therapies we did not find a synergic effect. Altogether, our results indicate that NRG1 isoforms play an important role on MN survival and that a viral-mediated overexpression may be considered as a potential novel therapy to treat ALS.
4
Bianchedi, Ferrando María Carolina. « Luxación lateral ». Trabajo final de especialización, Universidad Nacional de Cuyo. Facultad de Odontología, 2017. http://bdigital.uncu.edu.ar/9899.
Texte intégralRésumé :
Los dientes permanentes con ápice cerrado que sufren lesiones traumáticas como la luxación lateral con fractura de la tabla ósea vestibular deben considerarse una emergencia en odontología, ya que si se tratan dentro de las primeras horas de ocurrido el traumatismo, pueden ser reposicionados de forma manual, antes de que los tejidos de soporte se hayan reorganizado para eliminar la traba ósea apical, la compresión del ligamento periodontal a nivel cervical y apical y las alteraciones producidas en la oclusión por la migración de los elementos dentarios en sentido no
axial.Fil: Bianchedi Ferrando, María Carolina. Universidad Nacional de Cuyo. Facultad de Odontología.
5
Cera, Flávia Letícia Biff. « Co-lateral ». Florianópolis, SC, 2007. http://repositorio.ufsc.br/xmlui/handle/123456789/89597.
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Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Comunicação e Expressão. Programa de Pós-graduação em LiteraturaMade available in DSpace on 2012-10-22T23:58:01Z (GMT). No. of bitstreams: 1 247573.pdf: 911708 bytes, checksum: 2fde81da16a15e00ff99f3232d990d63 (MD5)
Hélio Oiticica e Ferréz nos apresentam o marginal em dois momentos decisivos. O primeiro encontra os "labirintos" em plena época de remoção das favelas, quando se tentava impedir o contato através do isolamento, época que coincide com o Golpe de 1964. Já Ferréz vive na extensão do estado de exceção e reivindica o título de literatura marginal, definida como "Aquela que vem da margem. De marginal, mesmo, até de cara que já roubou, que já passou pela vida". O marginal, nesta pesquisa, aparece cindido em duas concepções: a que mantém a relação com o centro, que chamamos de efeito colateral, e outra que suspende a relação. Partindo destas, leremos as proposições de Oiticica que se vinculam à favela de forma direta, sobretudo as da década de 1960: Éden, Barracão, Parangolé, Apocalipopótese, Mundo-Abrigo (década de 1970) e, com as referências a Cara de Cavalo e ao anti-herói anônimo. No que diz respeito à literatura marginal, trabalhamos em um primeiro momento com os dois romances inaugurais deste movimento, a saber, Cidade de Deus de Paulo Lins e Capão Pecado de Ferréz. Do efeito ao afeto, do colateral ao co-lateral, este percurso nos mostra o desafio que é pensar a vida, uma vez que só é possível pensá-la na margem, neste limiar que é um campo de batalha onde a vida se depara constantemente com o poder. Esta margem, no entanto, enquanto linha de fuga, não aparecerá necessariamente caracterizada pelos extremos, embora, como dissemos, orbite em torno da favela (que também não está necessariamente nas margens), mas sim como uma suspensão da relação entre limite e centro. Um limiar. The "marginal man" is presented by Hélio Oiticica and Ferréz in two decisive moments. Oiticica seeks the "labyrinths" in a period that, coinciding with the coup of 1964, is characterized by the prohibition of contact (by means of isolation), by the removing the "favelas" (slums). On the other side, Ferréz lives in the extension of the state of exception and reclaims the title of marginal literature, defined as "that (literature) which comes from the margin. Marginal, indeed, even dude that has already stolen that has been a criminal". The "marginal", in this research, appears broken in two conceptions: one that maintains itself in relation to a center, which we choose to call "collateral damage", and one which suspends that relation. With both these conceptions, we will try to read those of Oiticica's propositions which concerns to the slums in a direct form, specially, those of the 1960s: Éden, Barracão, Parangolé, Apocalipopótese, Mundo-Abrigo (this one from the 1970s) and also those related to Cara de Cavalo and to the anonymous anti-hero. We also worked on the two novels that inaugurate marginal literature: Cidade de Deus, written by Paulo Lins and Capão Pecado, by Ferréz. From effect to affection, from collateral to co-lateral, our path attempts to show that life is only thinkable in the margins, in this threshold that is a battlefield where life collides constantly with power. This margin, however, doesn't, in our research, appear necessarily characterized by the extremes, even if, as we said, the slum is its gravitational point, but as a suspension of the relation between center and limit: a threshold.
6
Stok, Andrew. « Lateral current injection s-laser with ion-implanted lateral heterobarriers ». Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape4/PQDD_0018/MQ49752.pdf.
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7
Hu, Ye. « Lateral Torsional Buckling of Wooden Beams with Mid-Span Lateral Bracing ». Thesis, Université d'Ottawa / University of Ottawa, 2016. http://hdl.handle.net/10393/35076.
Texte intégralRésumé :
An analytical and numerical investigation is conducted for the lateral torsional buckling analysis of wooden beam with a mid-span lateral brace subjected to symmetrically distributed loading. Two models are developed; one for the case of a rigid brace and another one for the case of a flexible brace. The analytical solutions are based on the principle of stationary potential energy and a Fourier expansion of the buckling displacement fields and bending moments. The validity of both models are verified against 3D finite element analyses in ABAQUS. Where applicable, verifications were also conducted against available solutions from previous studies. Parametric studies were conducted to investigate the effect of geometric and material parameters on the critical moments. The results indicate the presence of two separate groups of potential buckling modes, symmetric and anti-symmetric, with fundamentally different behavioural characteristics. The governing buckling mode is shown to depend on the bracing height, load height and lateral brace stiffness. The study shows that beyond a certain threshold bracing height, the critical moment is governed by the antisymmetric mode of buckling. Also, above a certain optimum bracing stiffness, no increase is observed in the critical moments. The models developed are used to construct a comprehensive database of parametric investigations which are then employed for developing simplified equations for determining the threshold heights, associated critical moments, and optimum stiffness.
8
Huzzey, Linda Mary. « Lateral variability in a coastal plain estuary (fronts, density, lateral circulation) ». W&M ScholarWorks, 1986. https://scholarworks.wm.edu/etd/1539616706.
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A series of observations of the density distribution across the York River estuary documents distinct lateral differences in density and degree of vertical mixing. The magnitude of the density differences varies throughout the tidal cycle; maximum lateral gradients occur at times of minimum current. When the density distribution is sufficiently inhomogeneous, longitudinal estuarine fronts are generated. These fronts are axially aligned, up to several miles in length, and are apparent for less than 2 hours at any given location. Although the density difference across the frontal boundary is often small, horizontal pressure gradients acting over a broad frontal region generate the convergent circulations necessary to maintain these fronts. Measurements of the longitudinal velocities across the same section reveals negligible phase difference but a significant amplitude difference between the currents in the channel and those over the shoals. Differential advection across the estuary due to this velocity shear is the process by which the observed density distribution is generated.
9
Botch, Catherine F. « Creativity, the lateral path less taken lateral thinking in the art classroom / ». Instructions for remote access. Click here to access this electronic resource. Access available to Kutztown University faculty, staff, and students only.xxx, 1997. http://www.kutztown.edu/library/services/remote_access.asp.
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Thesis (M. Ed.)--Kutztown University of Pennsylvania, 1997.Source: Masters Abstracts International, Volume: 45-06, page: 2745. Typescript. Abstract precedes thesis as preliminary leaves iv-v. Includes bibliographical references (leaves 98-103).
10
Amberetu, Mathew Atekwana. « Lateral superjunction power MOSFETs ». Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp05/MQ63012.pdf.
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11
Lester, Leo. « On Lateral Gene Transfer ». Thesis, University of Reading, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.487489.
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Is bacterial evolution phylogenetic or reticulate? Darwin showed that life's history W;J.S mappable with trees. For almost everytfillg that we can see about us, this is largely correct, but beyond the limit of our sight thrives the unseen majority: The tiny, singlecelled prokaryotes do not reserve their genes only for the next generation. Through lateral gene transfer they swap genes with contemporaries, regardless of species. Discovered in the war years, the true place of lateral gene transfer within evolution has not yet been settled. As work on it.has multiplied, so its apparent extent has grown. Here a reappraisal of lateral gene transfer is carried out. The methods of its detection are examined and refined. The ~sults show that lateral transfer is not nearly so prevalent as some say. Less frequent, but still important, lateral gene transfer is shown to be a key mover in the evolution of the entire eukaryote domain. Its effect on individual genes, how it can increase rates of evolution and even trigger 'positive selection regimes, is exposed. The interconnectivity of species is then explored. Species that are the source of many genes receive many. Species that receive lots of genes through lateral transfer hold fewer unique genes. In addition, it is as if all species are connected through a massive network of lateral transfers. But any new information must be placed in its proper context: lateral gene transfer is only one of evolution's tools. Convergent evolution is exposed as a problem, both when trying to detect lateral transfer and perhaps also when constructing phylogenies. For all our problems with bacterial phylogenies, with building and interpreting them, the lesson of lateral gene transfer is that we can have faith in the idea of bacterial species and, after almost a hundred and fifty years, in Darwin too.
12
Boyd, Kudakwashe. « Lateral and subjacent support ». Thesis, Stellenbosch : University of Stellenbosch, 2009. http://hdl.handle.net/10019.1/2763.
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Thesis (LLM (Public Law))--University of Stellenbosch, 2009.ENGLISH ABSTRACT: The first part of this thesis deals with the right of lateral and subjacent support and explains how it should be applied in South African law. The thesis illustrates how the neighbour law principles of lateral support were incorrectly extended to govern conflicts pertaining to subjacent support that arose in South African mining law. From 1911 right up to 2007, these two clearly distinguishable concepts were treated as synonymous principles in both academic writing and case law. The thesis plots the historical development of this extension of lateral support principles to subjacent support conflicts. In doing so, it examines the main source of South Africa’s law of support, namely English law. The thesis then shows how the Supreme Court of Appeal in Anglo Operations Ltd v Sandhurst Estates (Pty) Ltd 2007 (2) SA 363 (SCA) illustrated how the English law doctrine of subjacent support, with all its attendant ramifications, could not be useful in resolving disputes that arise between a land surface owner and a mineral rights holder in South African mining law. The second of half of the thesis investigates the constitutional implications of the Supreme Court of Appeal’s decision in Anglo Operations in light of the systemic changes introduced by the Minerals and Petroleum Resources Development Act 28 of 2002. In terms of this new Act, all the mineral and petroleum resources of South Africa are the common heritage of the people of South Africa, and the state is the custodian thereof. This means that landowners are no longer involved in the granting of mineral rights to subsequent holders. In light of the Anglo Operations decision, landowners in the new dispensation of mineral exploitation face the danger of losing the use and enjoyment of some/all their land. The thesis therefore examines the implications of the statutory provisions in South African legislation (new and old) that have/had an impact on the relationship between landowners and mineral right holders with regard to the question of subjacent support, as well as the implications of the Anglo Operations decision for cases where mineral rights have been granted under the statutory framework.
AFRIKAANSE OPSOMMING: Die eerste deel van die tesis handel oor die reg op sydelingse en oppervlakstut en hoe dit in die Suid-Afrikaanse reg toegepas behoort te word. Die tesis wys hoe die bureregbeginsels rakende sydelingse stut verkeerdelik uitgebrei is na konflikte rakende oppervlakstut wat in die Suid-Afrikaanse mynreg ontstaan het. Vanaf 1911 en tot in 2007 is hierdie twee duidelik verskillende konsepte in sowel akademiese geskrifte en in die regspraak as sinonieme behandel. Die tesis sit die historiese ontwikkeling van die uitbreiding van laterale stut-beginsels na oppervlakstut-konflikte uiteen. In die proses word die hoofbron van die Suid-Afrikaanse reg ten aansien van steun, naamlik die Engelse reg, ondersoek. Die tesis wys uit hoe die Hoogste Hof van Appèl in Anglo Operations Ltd v Sandhurst Estates (Pty) Ltd 2007 (2) SA 363 (SCA) beslis het dat die Engelse leerstuk van oppervlakstut met al sy meegaande implikasies nie in die Suid-Afrikaanse reg sinvol aangewend kan word om dispute wat tussen die oppervlakeienaar van grond en die mineraalreghouer ontstaan, op te los nie. Die tweede helfte van die tesis ondersoek die grondwetlike implikasies van die Hoogste Hof van Appèl se beslissing in Anglo Operations in die lig van die sistemiese wysigings wat deur die Wet op Ontwikkeling van Minerale en Petroleumhulpbronne 28 van 2002 tot stand gebring is. Ingevolge die nuwe Wet is alle mineraal- en petroleumhulpbronne die gemeenskaplike erfenis van alle mense van Suid-Afrika en die staat is die bewaarder daarvan. Dit beteken dat grondeienaars nie meer betrokke is by die toekenning van mineraalregte aan houers daarvan nie. In die lig van die Anglo Operations-beslissing loop grondeienaars die gevaar om die voordeel en gebruik van al of dele van hulle grond te verloor. Die tesis ondersoek daarom die implikasies van verskillende bepalings in Suid-Afrikaanse wetgewing (oud en nuut) wat ‘n impak op die verhouding tussen die grondeienaar en die houer van die mineraalregte het, sowel as die implikasies van Anglo Operations vir gevalle waar mineraalregte onder die nuwe statutêre raamwerk en toegeken is.
13
Rachel, Chad. « An Investigation and Comparison of Accepted Design Methodologies for the Analysis of Laterally Loaded Foundations ». ScholarWorks@UNO, 2003. http://scholarworks.uno.edu/td/55.
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Single piles and pile groups are frequently subjected to high lateral forces. The safety and functionality of many structures depends on the ability of the supporting pile foundation to resist the resulting lateral forces. In the analysis and design of laterally loaded piles, two criterions usually govern. First, the deflection at the working load should not be so excessive as to impair the proper function of the supporting member. Second, the ultimate strength of the pile should be high enough to take the load imposed on it under the worst loading condition. Typically, pile length, pile section, soil type, and pile restraint dictate the analysis. This paper presents different methods, specifically Broms' method and the p-y method, for both the analysis and design of laterally loaded single piles. Both linear and nonlinear analyses are considered. The measured results of several full-scale field tests performed by Lymon Reese are compared to computed results using Broms' method of analysis and the p-y method of analysis. Observations are made as to the correlation between the results and recommendations are made as to the applicability of the accepted methods for the analysis and design of laterally loaded piles.
14
Boucher-Thrasher, Annette. « Evidence for anatomical connectivity between lateral hypothalamic and lateral preoptic area brain stimulation sites ». Thesis, University of Ottawa (Canada), 1987. http://hdl.handle.net/10393/5246.
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Korndörfer, Joachim. « Untersuchungen zur Herstellung eines hydraulischen Bindemittels auf der Basis eines Rückstandes des Bergbaus von lateritischen Erzen ». [S.l. : s.n.], 2000. http://deposit.ddb.de/cgi-bin/dokserv?idn=961038020.
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Bhutada, Manish Kumar. « Functional Properties Of The Superior Head Of Human Lateral Pterygoid Muscle ». Thesis, The University of Sydney, 2006. http://hdl.handle.net/2123/5038.
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Ozdemir, Kerem Murat. « Lateral Buckling Of Overhanging Beams ». Master's thesis, METU, 2005. http://etd.lib.metu.edu.tr/upload/12606488/index.pdf.
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Lateral torsional buckling should be taken into account during the design of overhanging steel beams. One special type of overhanging beams is the crane trolley monorails. Lateral buckling of overhanging monorails under idealized loading and
boundary conditions has been studied in the past using classical mathematical procedures. This thesis aims to present a detailed investigation of overhanging monorails using finite element analysis. Effects of different loading and boundary
conditions were studied in detail. It was found out that the location of loading and supports on the cross section have significant effects on the buckling capacity. Beams having different warping and torsional properties were analyzed. The effects of cross section distortion on buckling capacity were investigated for beams with single and double overhangs. The reduction in capacity due to cross section distortion has been
quantified. Based on the analysis results simple design recommendations were developed for lateral buckling of overhanging monorails and they are presented herein.
18
Miles, David John. « Lateral thermal buckling of pipelines ». Thesis, University of Cambridge, 1998. https://www.repository.cam.ac.uk/handle/1810/251654.
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19
Dwivedi, Tashi. « Aerodynamic damping in lateral buffeting ». Thesis, University of Ottawa (Canada), 2001. http://hdl.handle.net/10393/9204.
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Using the balanced cantilever method of erection, the cable-stayed bridge during its critical construction phase resembles a long overhanging cantilever structure. This type of structure is particularly vulnerable to wind-induced buffeting instabilities because of its low natural frequencies and low overall stiffness. In the past, the critical buffeting case for both vertical and horizontal excitation was assumed to occur when the wind was incident perpendicular to the bridge's axis. Recent observations in some cable-stayed bridges during construction revealing higher lateral responses at yaw angles other than perpendicular have triggered interest in the lateral vibration case. Buffeting instabilities are affected mainly by the aerodynamic damping term. Experimental research for the vertical aerodynamic damping resulted in the cosine approximation. In the absence of available experimental data for lateral vibration, the cosine approximation is extended from the vertical case and assumed to be valid for the lateral aerodynamic term. The experimental section of this thesis attempts to clarify the validity of the cosine approximation for the lateral aerodynamic damping case. Cantilever-type section models are triggered into vibration under various wind speeds and over a range of yaw angles, the aerodynamic damping is calculated, and the results are studied.
20
Holmes, D. M. « Lateral drying of ceramic suspensions ». Thesis, University of Cambridge, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.604187.
Texte intégralRésumé :
Many ceramic processing routes, such as tape casting, screen-printing and ink jet printing, involve deposition of a suspension of ceramic particles in a prescribed shape on a substrate. As the liquid evaporates from the suspension, the particles pack together and liquid leaves the pores. In water-based suspensions, these processes often occur at fronts that move from the edge to the centre of the drying layer. This is known as lateral drying. As drying proceeds, the body can change shape, residual stresses can develop and cracking can occur. However, existing models cannot predict either the shape changes that occur or adequately explain why the drying layer cracks. To study this, the drying behaviour of layers of alumina suspensions was investigated experimentally. Measurements were made of the movement of lateral fronts, the changes in local thickness and the activity at the surface of the layers, and the cracking behaviour and the dried thickness profiles were studied. By considering the redistribution of liquid at the first lateral front, where particles pack together, an expression for the thickness profile of the dried layers has been derived. Mass loss data, together with the local thickness measurements, suggest that the particles do not come into touching contact at this first front. Instead, a collapse event occurs when the repulsive layers between the particles are overcome. The development of stress in a drying layer is generally attributed to the build-up of capillary pressure at the surface of the body. However, this causes compression of the particle network, despite the constraint to shrinkage imposed by the substrate, and therefore cannot explain why cracking occurs. Here, it is proposed that the driving force for cracking actually arises from the collapse event. This predicts that cracking should occur while the space between the particles is still filled with liquid. This is consistent with the measurements of surface activity and local thickness, and the cracking behaviour observed.
21
Carroll, Seàn P. « Crowd-induced lateral bridge vibration ». Thesis, University of Nottingham, 2013. http://eprints.nottingham.ac.uk/28410/.
Texte intégralRésumé :
Vibration induced by walking pedestrians has motivated research in the civil engineering community for many years. An area within this broad field that has received particular attention is the dynamic interaction that can occur between pedestrians and laterally flexible bridge structures. Perhaps the most notable example occurring on the opening day of London's Millennium Bridge. The enduring interest in this research problem is fuelled by two of its key features; (i) the sensitivity and adaptability of human balance to lateral motion and (ii) the spatial and temporal variation in flow characteristics exhibited by a pedestrian crowd. Both of these features are addressed herein. In this project an experimental campaign was executed with the aim of identifying the interaction mechanism by which pedestrians produce force harmonics, that resonate with the oscillating structure on which they walk. These so-called self-excited forces have been experimentally identified by others but the underlying reason for their existence has remained an open question. In an effort to address this, human balance behaviour while walking on a laterally oscillating treadmill was recorded using 3-dimensional motion capture equipment. Subsequent analysis revealed that human response to sinusoidal base motion is dominated by periodic alteration of foot placement position. This produces amplitude modulation of the lateral component of the ground reaction force and is ultimately responsible for the self-excited force harmonics. It was further revealed that human centre of mass motion while walking on an oscillating structure is predominantly passive. The passive inverted pendulum model is thus an excellent model of pedestrian frontal plane balance. The second facet of this work is concerned with developing a crowd-structure interaction model that builds upon the current state of the art. The model presented utilises the understanding of human-structure interaction identified above and employs an agent-based modelling approach. Thus, the resulting 'virtual crowd' is capable of simulating key crowd features, such as inter-subject variability and emergent velocity-density flow behaviour. Using this model, it is shown that the experimentally identified human-structure interaction mechanism can lead to large amplitude lateral deck oscillations, consistent with field observations reported in the literature. The model successfully predicts the multi-mode instability of Bristol's Clifton Suspension Bridge in the absence of step frequency tuning among the crowd. This provides supporting evidence for the model's validity. The work described above has resulted in a clearer understanding of the feedback between pedestrian balance behaviour and bridge response. Furthermore, the modelling techniques developed have potential for application in the wider study of crowd-induced vibration of dynamically susceptible structures.
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Wu, Yung-chuan John, et 吳永傳. « Lateral cephalometrics in southern Chinese ». Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2014. http://hdl.handle.net/10722/206470.
Texte intégralRésumé :
The lateral cephalometric radiograph (LCR) is an important tool in orthodontics to aid diagnosis, inform treatment planning and to evaluate treatment outcomes. Following identification of frequently used cephalometric analyses in the literature, the aims of this thesis were: (i) to establish cephalometric norm values for 12-year-old southern Chinese children for the modified Björk’s analysis, Jacobson’s Wits appraisal, Pancherz’s Sagittal Occlusal (SO) and Vertical Occlusal (VO) analyses (Paper I and II); (ii) to identify gender and racial/ethnic variations in cephalometric norm values (Paper I and II); (iii) to extrapolate from the cephalometric norm values of 12-year-old southern Chinese to produce norm values for 10, 11, 13 and 14-year-old - for these common aforementioned cephalometric analyses and McNamara’s analysis (Paper III); (iv) to investigate variations in the cephalometric characteristics of southern and northern Chinese children (Paper IV); and (v) to study the relationship between common cephalometric reference planes and the True Horizontal Plane (THP), and variations with respect to gender (Paper V).
Extant LCRs from a community based sample of 200 male and 205 female 12-year-old southern Chinese in Hong Kong; 86 Caucasian children and 100 northern Chinese children, were traced and digitized twice employing the Computer Assisted Simulated for Orthognathic Surgery (CASSOS) program. Cephalometric norm values were created and extrapolated for 10 to 14-year-old. Gender and racial/ethnic variations were determined. In addition, the relationship between some common cephalometric reference planes (Sella Nasion Plane - SNP; Constructed Horizontal Plane - CHP; Frankfurt Horizontal Plane - FHP; Upper Occlusal Plane - UOP; Functional Occlusal Plane - FOP) and the THP was determined; and gender differences examined.
Cephalometric norm values for modified Björk’s analysis, Jacobson’s Wits appraisal and Pancherz’s SO & VO analyses were produced for 12-year-old southern Chinese children. Variations in cephalometric norm values with respect to gender (P<0.05) and race/ethnicity (P<0.05) were observed. Extrapolated cephalometric norm values for modified Björk’s analysis, Jacobson’s Wits appraisal, Pancherz’s SO & VO analyses, and McNamara’s analysis were produced for 10 to 14-year-old. Variations in cephalometric norm values with respect to age (P<0.05), gender (P<0.05) and race/ethnicity (P<0.05) were observed. Furthermore, variations in cephalometric values between southern and northern Chinese children were evident (P<0.05), and between Caucasians and both Chinese groups (P<0.05). The mean inclination between THP and the conventional cephalometric planes differed significantly from zero: SNP/THP (P<0.05), UOP/THP (P<0.05), FOP/THP (P<0.05); and gender differences were apparent (P<0.05).
In conclusion, norm values for frequently used cephalometric analyses were produced for 12-year-old southern Chinese, and extrapolated to produce norm values for 10 to 14-year-old. Age, gender and racial/ ethnic differences were apparent, supporting the need for age, gender and racial/ethnic specific norms. Common cephalometric reference planes differed to THP, and this warrants consideration in cephalometric analyses.published_or_final_version
Dentistry
Doctoral
Doctor of Philosophy
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Soom, Mohd Amin Mohd. « Hydraulic analysis of trickle lateral ». Thesis, University of Southampton, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.277631.
Texte intégral
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Chok, Kermin 1980. « Lateral systems for tall buildings ». Thesis, Massachusetts Institute of Technology, 2004. http://hdl.handle.net/1721.1/30135.
Texte intégralRésumé :
Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2004.Includes bibliographical references.
The advances in three-dimensional structural analysis and computing resources have allowed the efficient and safe design of increasingly taller structures. These structures are the consequence of increasing urban densification and economic viability. The modern skyscraper has and will thus continue to feature prominently in the landscape of urban cities. The trend towards progressively taller structures has demanded a shift from the traditional strength based design approach of buildings to a focus on constraining the overall motion of the structure. Structural engineers have responded to this challenge of lateral control with a myriad of systems that achieve motion control while adhering to the overall architectural vision. An investigation was carried out to understand the behavior of the different lateral systems employed in today's skyscrapers. The investigation examined the structural behavior of the traditional moment frame, the braced frame, the braced frame with outriggers and finally the tubular structure. The advantages and disadvantages of all schemes were explored from both an architectural and structural efficiency standpoint. Prior to the computer modeling of each lateral system, each scheme was understood from an analytical standpoint to both verify computer results and to illustrate the importance of hand calculations. The study repeatedly illustrated that motion was the governing condition and this led to the proposal of an approach for the design of braced frames.
by Kermin Chok.
M.Eng.
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Rehmanjee, Yasmin H. (Yasmin Hydery) 1976. « Lateral vibration of pedestrian bridges ». Thesis, Massachusetts Institute of Technology, 2001. http://hdl.handle.net/1721.1/84286.
Texte intégralRésumé :
Thesis (M.Eng.)--Massachusetts Institute of Technology, Dept. of Civil and Environmental Engineering, 2001."June 2001."
Includes bibliographical references (leaf 56).
by Yasmin H. Rehmanjee.
M.Eng.
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Souza, Sergio Pereira de. « Tombamento lateral de tratores agricolas ». Universidade de São Paulo, 2002. http://teses.usp.br/teses/disponiveis/11/11148/tde-20181127-161937/.
Texte intégralRésumé :
Os inúmeros acidentes de trabalho na agricultura têm exigido esforços de diversos setores no sentido de torná-los menos freqüentes, devido aos problemas que acarretam à atividade agrícola e na intensidade em que ocorrem. Em alguns países estes acidentes lideram os registros de acidentes fatais, acompanhados de perto dos registros observados nas atividades de mineração e da construção civil. Dentre os diversos tipos de acidentes na atividade agrícola, os de maior ocorrência são os que envolvem tratores agrícolas, em especial, os do tipo tombamentos. Estes, por sua vez, podem ser frontais (empinamento) ou laterais. Os tombamentos laterais são os mais freqüentes, com 75% do total dos registros de tombamentos. Como proposta de prevenção a esse tipo de acidente avaliou-se a possibilidade do emprego de um clinômetro, disponível no Departamento de Engenharia da ESALQ-USP. Este instrumento mede ângulo de inclinação e têm apresentado grande aplicação em diversas áreas. Inicialmente foram determinadas suas características estáticas tais como curva de calibração, sensibilidade estática, faixa de leitura, erros e histerese. Para tanto utilizou-se uma mesa de seno. Na seqüência, esse clinômetro foi instalado em um trator e avaliou-se seu comportamento em três taludes de inclinações distintas. Dos seis cenários criados nos ensaios dinâmicos, em apenas um deles, onde houve inclinação à direita e na maior declividade, o clinômetro não apresentou semelhança|estatisticamente significativa com a referência. O clinômetro instalado em um trator reproduziu os taludes a que foi exposto, indicando ser um instrumento útil na prevenção de tombamento lateral de tratores na medida em que alerta o operador quanto à exposição ao risconot available
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AL-SHADEEDI, AKRAM. « LATERAL AND VERTICAL ORGANIC TRANSISTORS ». Kent State University / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=kent1492441683969202.
Texte intégral
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Manickaraj, Nagarajan. « Neuromotor Characteristics of Lateral Epicondylalgia ». Thesis, Griffith University, 2017. http://hdl.handle.net/10072/365841.
Texte intégralRésumé :
Neuromotor dysfunction such as delayed upper extremity reaction time and altered wrist posture during gripping, are considered part of the pathophysiology in lateral epicondylalgia (LE). This might manifest as changes in the forearm muscle activity patterns in LE. In addition to a systematic review (Study 1) of the current literatures of forearm muscle activity in LE, this thesis presents three case-control studies that provide new insights into: the timing of forearm muscle activity during wrist extension reaction time (RT) (Study 2), the magnitude of forearm muscle activity during isometric gripping with different wrist postures (Study 3), and forearm muscle synergies during ramp and steady-state phases of isometric gripping (Study 4) in individuals with LE. This thesis also presents the association of forearm muscle activity with the clinical, sensory and tendon structural changes associated with LE. The systematic review identified consistent evidence of increased electromechanical delay and altered cortical excitability associated with the forearm extensor muscles in LE. These findings suggest both peripheral and central contribution to altered motor control in LE. The second study, which used intramuscular electromyography (EMG), provided evidence that delayed RT in LE is due to prolonged extensor carpi radialis brevis (ECRB) and extensor digitorum communicis (EDC) motor time, with no between-group differences in premotor time. Wrist extension RT was associated only with ECRB and EDC premotor time but not with extensor carpi ulnaris (ECU) premotor in LE. Increased duration of LE symptoms was associated with shorter RT, as well as shorter ECRB and anconeus premotor time.Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Allied Health
Griffith Health
Full Text
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Ambrose, Joseph George. « Deconvolution of lateral shear interferograms ». Diss., The University of Arizona, 1994. http://hdl.handle.net/10150/186610.
Texte intégralRésumé :
This dissertation develops and presents an existing but little known method to provide an exact solution to the Wavefront Difference Equation routinely encountered in the reduction of Lateral Shear Interferograms (LSI). The method first suggested by Dr. Roland Shack treats LSI as a convolution of the wavefront with an odd impulse pair. This representation casts the Lateral Shear problem in terms of Fourier optics operators and filters with a simplified treatment of the reduction of the LSI possible. This work extends the original proposal applied to line scans of wavefronts to full two-dimensional recovery of the wavefront along with developing the associated mathematical theory and computer code to efficiently execute the wavefront reduction. Further, a number of applications of the wavefront reduction technique presented here are developed. The applications of the filtering technique developed here include optical imaging systems exhibiting the primary aberrations, a model of residual tool marks after fabrication and propagation of an optical probe through atmospheric turbulence. The computer program developed in this work resides on a PC and produces accurate results to a 1/500 wave when compared to ray traced input wavefronts. The combination of the relatively simple concept providing the basis of the reduction technique with the highly accurate results over a wide range of input wavefronts makes this a timely effort. Finally, the reduction technique can be applied to the accurate testing of aspheric optical components.
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Nordström, Gustav, et Markus Lawergren. « Fysioterapi vid akut lateral fotledsdistorsion ». Thesis, Luleå tekniska universitet, Institutionen för hälsovetenskap, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-72545.
Texte intégralRésumé :
Abstrakt Inledning: Laterala fotledsdistorsioner är en av de vanligaste skadorna hos motionärer och idrottande individer. Om den akuta skadan inte behandlas optimalt kan detta leda till komplikationer såsom degenerativa förändringar och kronisk instabilitet. Olika former av fysioterapeutiska behandlingsinterventioner såsom, proprioceptionsträning, styrketräning, manuella terapier, kyla/värme, externa stöd, elterapi och multimodala behandlingar används kliniskt av fysioterapeuter för att bygga upp strukturerna i foten och minska risken för återstukning. Syfte: Sammanställa vetenskaplig kunskap och värdera effekten av fysioterapeutiska åtgärder vad gäller smärta, funktion och upprepade fotledsdistorsioner vid akuta laterala fotledsdistorsioner. Metod: Databaserna Pubmed och Pedro användes i litteratursökningen. Detta resulterade i 79 träffar i Pubmed och 60 i Pedro, varav 17 artiklar inkluderades. Resultat: Varken träning, manuella terapier, värme/kyla, externt stöd, multimodal träning eller elterapi är mer effektivt än någon annan behandling för att förbättra smärta, funktion och minska upprepade fotledsdistorsioner efter en lateral fotledsdistorsion. Konklusion: I det akuta skedet verkar inte valet av behandlingsmetod ha en stor inverkan på rehabilitering vid fotledsdistorsioner om durationen är för kort eller frekvensen för låg. Fler RCT-studier inom området med längre duration och högre frekvens behöver göras för att kunna dra en definitiv slutsats om de olika behandlingsmetodernas effekt vid denna skada.
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Grández, Molina Madeleine Alessandra. « Comparación de la distorsión geométrica lineal de la telerradiografía digital con la telerradiografía convencional en cráneos humanos ». Bachelor's thesis, Universidad Peruana de Ciencias Aplicadas (UPC), 2014. http://hdl.handle.net/10757/322462.
Texte intégralRésumé :
The lateral cephalometric radiography is an essential tool in clinical practice, especially in the area of orthodontics, allows measurements to investigate the development and growth of the facial skeleton , aiding in the diagnosis and treatment plan for each patient. The first type of radiography was the conventional were used and the development of technology has evolved to be digital . The purpose of this study was to compare the geometric distortion of digital lateral cephalometric with conventional cephalometric in human cadaver skulls . The sample was taken for convenience and was composed of 21 human cadavers dry skulls, three markers were placed on each skull lead. The first marker was at the level of the junction of the sutures sphenofrontal, coronal , flaky and sphenosquamosa and parallel to the Frankfort plane . The second one below the frontozygomatic suture and the last at the branch level of the jaw and positioned in the concave part of the line above and parallel to the Frankfort plane . No significant differences were found when comparing the measurements of conventional and digital plates in the upper and middle third, but when the last third was analyzed differences were found between conventional and digital images . All the images presented distortion when they were compared with the gold standard.La telerradiografía lateral es una herramienta esencial en la práctica clínica especialmente en el área de ortodoncia, nos permite realizar mediciones para investigar el desarrollo y crecimiento del esqueleto facial, ayudando en el diagnóstico y plan de tratamiento de cada paciente. El primer tipo de radiografía utilizada fueron las convencionales y con el desarrollo de la tecnología, fue evolucionando hasta ser digital. El propósito de este estudio fue comparar la distorsión geométrica de la telerradiografía lateral digital con la telerradiografía convencional en cráneos de cadáveres humanos. La muestra fue tomada por conveniencia, siendo conformada por 21 cráneos secos de cadáveres humanos, se le colocaron tres marcadores de plomo a cada cráneo. El primer marcador estuvo a nivel de la unión de las suturas esfenofrontal ,coronal, escamosa y esfenoescamosa y paralelo al plano de Frankfort. El segundo debajo de la sutura frontocigomática y el último a nivel de la rama de la mandíbula y posicionado en la parte más cóncava de la línea anterior y paralela al plano de Frankfort. No se hallaron diferencias significativas al comparar las medidas de las placas convencionales y digitales en el tercio medio y superior, pero al analizar el tercer tercio si se hallaron diferencias entre las imágenes convencionales y digitales. En cuanto a la comparación con el gold standard, todas las placas presentaron distorsión. PALABRAS CLAVES: telerradiografía lateral, distorsión, telerradiografía convencional, telerradiografía digital
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Quesada, González Daniel. « Design and application of nanomaterial-based lateral flow devices ». Doctoral thesis, Universitat Autònoma de Barcelona, 2018. http://hdl.handle.net/10803/665602.
Texte intégralRésumé :
Els biosensors de fluxe lateral són dispositius basats en paper d'alta rellevància en diagnòstics "point-of-care" i monitoratge ambiental. Aquests dispositius són de baix cost, ràpids, robustos i simples de fer servir.
En aquesta recerca, els dispositius de fluxe lateral són aplicats per la detecció d'ions d'urani en aigua potable amb alta sensibilitat i baix temps d'assaig. El límit de detecció obtingut amb aquest assaig ha estat 40 nM, tres vegades inferior a la quantitat màxima recomanada d'urani en aigües de consum.
També, una nova estratègia per incrementar la senyal colorimètrica en les tires de fluxe lateral és reportada. Les nanofibres de cel·lulosa poden ésser introduïdes als nanoporus de la nitrocel·lulosa, matriu on les reaccions de fluxe lateral succeeixen, augmentant l'àrea on les biomolècules poden enganxar-se, incrementant així la probabilitat de retenir les partícules responsables del senyal en mostres positives. Seguint aquesta estratègia, s'ha aconseguit un increment del senyal colorimètric d'un 30%.
I finalment, nanopartícules d'òxid d'iridi són reportades per primera vegada als assaigs de fluxe lateral com a senyalitzadors colorimètrics. Les propietats electroquímiques d'aquest nanomaterial permeten, a més d'una resposta òptica, la quantificació electroquímica de la mostra tal com s'ha demostrat detectant èters de difenil polibrominats aplicant nanopartícules d'òxid d'iridi en elèctrodes serigrafiats de carboni.
La recerca bibliogràfica realitzada ha esdevingut en tres publicacions:
• Quesada-González, D. & Merkoçi, A. “Nanoparticle-based lateral flow biosensors”. Biosens. Bioelectron. 73, 47–63 (2015).
• Quesada-González, D. & Merkoçi, A. “Mobile phone–based biosensing: an emerging ‘diagnostic and communication’ technology”. Biosens. Bioelectron. 92, 549–562 (2016).
• Quesada-González, D. & Merkoçi, A. “Nanomaterial-Based Devices for Point-of-Care Diagnostic Applications”. Chem. Soc. Rev. 47, 4697–4709 (2018).
També el treball experimental ha esdevingut en 4 articles encara no publicats:
• Quesada-González, D.; Jairo, G. A.; Blake, R.C., Blake, D.A. & Merkoçi, A. “Uranium (VI) detection in groundwater using a gold nanoparticle/paper-based lateral flow device”. Under revision (2018).
• Quesada-González, D.; Stefani, C.; González, I.; de la Escosura-Muñiz, I.; Domingo, N.; Mutjé, P. & Merkoçi, A. “Signal enhancement on gold nanoparticle-based lateral flow tests using cellulose nanofibers”. In preparation (2018).
• Quesada-González, D.; Baiocco, A.; Martos, A. A.; de la Escosura-Muñiz, A.; Palleschi, G. & Merkoçi, A. “Iridium oxide (IV) nanoparticle-based electrocatalytic detection of PBDE”. Under revision (2018).
• Quesada-González, D.; Sena-Torralba, A.; Wicaksono, W. P.; de la Escosura-Muñiz, A.; Ivandini, T. A. & Merkoçi A. “Iridium oxide (IV) nanoparticle-based lateral flow immunoassay”. In preparation (2018).Lateral flow biosensors are paper-based devices of high relevance in point-of-care diagnostics and environmental monitoring. These devices are low-cost, fast, robust and simple to use. In this research, lateral flow biosensors are applied for the detection of uranium ions in drinking water with high selectivity and low assay time. The limit of detection reached in this assay was of 40 nM, three times lower than the maximum amount of uranium recommended in consume water. Also, a novel colorimetric signal enhancement strategy on lateral flow strips is reported. Cellulose nanofibers can be introduced into nitrocellulose pores, the matrix in which lateral flow reactions occur, increasing the area where biomolecules can be attached, increasing then the probability of stopping label particles on positive samples. Following this strategy, a 30% of color signal enhancement was achieved. And last, iridium oxide nanoparticles are reported for the first time on lateral flow assays as colorimetric labels. The electrocatalytical properties of this nanomaterial allow, besides the colorimetric response, electrochemical quantification of the sample as it is demonstrated by detecting polybrominated diphenyl ethers using iridium oxide nanoparticles on screen printed carbon electrodes. The state-of-the art studies carried out resulted in three review publications: • Quesada-González, D. & Merkoçi, A. “Nanoparticle-based lateral flow biosensors”. Biosens. Bioelectron. 73, 47–63 (2015). • Quesada-González, D. & Merkoçi, A. “Mobile phone–based biosensing: an emerging ‘diagnostic and communication’ technology”. Biosens. Bioelectron. 92, 549–562 (2016). • Quesada-González, D. & Merkoçi, A. “Nanomaterial-Based Devices for Point-of-Care Diagnostic Applications”. Chem. Soc. Rev. 47, 4697–4709 (2018). Also the experimental work performed conducted to four full length articles not yet published: • Quesada-González, D.; Jairo, G. A.; Blake, R.C., Blake, D.A. & Merkoçi, A. “Uranium (VI) detection in groundwater using a gold nanoparticle/paper-based lateral flow device”. Under revision (2018). • Quesada-González, D.; Stefani, C.; González, I.; de la Escosura-Muñiz, I.; Domingo, N.; Mutjé, P. & Merkoçi, A. “Signal enhancement on gold nanoparticle-based lateral flow tests using cellulose nanofibers”. In preparation (2018). • Quesada-González, D.; Baiocco, A.; Martos, A. A.; de la Escosura-Muñiz, A.; Palleschi, G. & Merkoçi, A. “Iridium oxide (IV) nanoparticle-based electrocatalytic detection of PBDE”. Under revision (2018). • Quesada-González, D.; Sena-Torralba, A.; Wicaksono, W. P.; de la Escosura-Muñiz, A.; Ivandini, T. A. & Merkoçi A. “Iridium oxide (IV) nanoparticle-based lateral flow immunoassay”. In preparation (2018).
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St-Amour, Rémi. « Lateral Torsional Buckling of Wood I-Joist ». Thesis, Université d'Ottawa / University of Ottawa, 2016. http://hdl.handle.net/10393/35161.
Texte intégralRésumé :
Engineered wood I-joists have grown in popularity as flooring and roofing structural systems in the past 30 years, replacing solid sawn lumber joists. Typical wood I-joists are manufactured with a very slender section, which is desirable to achieve higher flexural capacities and longer spans; however, this makes them susceptible to lateral torsional buckling failure. Continuous beam spans and uplift forces on roof uplift are potential scenarios where lateral instability can occur and reflects the need to investigate the lateral torsional buckling behavior of wood I-joists. Within this context, the present study conducts an experimental investigation on the material properties and the critical buckling load of 42 wood I-joist specimens. A 3D finite element model is built using the experimentally determined material parameters to effectively predict the observed buckling behavior of the specimens while also accounting for initial imperfections in the joists. The adequacy of other analytical models to predict the critical buckling load of wood I-joists are also investigated. It is demonstrated that the American design standard underestimates the critical buckling load of wood I-joists while the classical theory provides an adequate estimate of the buckling capacity. Furthermore, the effects of initial imperfections on the lateral torsional buckling behavior are discussed. The developed and verified FE model is used to reproduce the nonlinear buckling behavior of the wood I-joist and also to provide an accurate estimate of the lateral torsional buckling capacity using the linear buckling analysis.
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Godinho, Vanda Cristina Ng. « Esclerose lateral amiotrófica : revisão bibliográfica da patofisiologia ». Master's thesis, Universidade da Beira Interior, 2013. http://hdl.handle.net/10400.6/1402.
Texte intégralRésumé :
A Esclerose Lateral Amiotrófica (ELA) é uma doença do neurónio motor fatal e progressiva, cuja patogenia é ainda desconhecida.
O processo patológico decorre de uma degenerescência dos neurónios motores periféricos no tronco encefálico e medula espinhal, que leva a desnervação e consequente atrofia nas fibras musculares correspondentes. Nas regiões onde ocorre adelgaçamento das fibras nervosas há deposição de pigmentos lipídicos e outras substâncias conjuntamente com proliferação de astroglia e microglia. No início do processo patológico, alguns grupos musculares vão sendo afetados, levando a uma fraqueza muscular assimétrica pouco específica. Com o avançar da doença, vai sendo maior o número de músculos envolvidos, acabando por comprometer a musculatura respiratória e levando à morte.
O fenómeno que leva à destruição neuronal ainda não foi esclarecido, o que faz com que esta patologia de rápida progressão seja ainda um grande problema no seio da Neurologia. Devido à ausência de uma etiologia específica, fatores de risco exógeno estão a ser cada vez mais explorados como agente causal da doença. A descoberta contínua de mutações em genes de pacientes com ELA faz com que os fatores genéticos adquiram uma maior importância na etiopatogénese da doença, principalmente porque parecem estar diretamente relacionados com os diversos processos que levam à destruição dos neurónios motores.
Os mecanismos que levam à destruição são diversos, entre eles o mecanismo de stress oxidativo, excitotoxicidade pelo glutamato, agregação proteica, alteração da função dos astrócitos, alterações neurovasculares, processos inflamatórios e disfunção dos neurofilamentos e microtúbulos. Nenhum destes processos funciona de modo isolado e diversos estudos apontam para um mecanismo em constante interação que culmina no dano e morte neuronais.
O conhecimento escasso da fisiopatologia desta doença leva à dificuldade na elaboração de estratégias terapêuticas eficazes para abrandar o curso da doença. No momento apenas o Riluzole mostra resultados, embora com um aumento da sobrevida dos pacientes em apenas alguns meses. Com o decorrer dos estudos, mais aspetos da ELA têm vindo a ser desvendados, abrindo assim novas possibilidades e hipóteses para estudos mais aprofundados.The Amyotrophic Lateral Sclerosis (ALS) is a fatal and progressive motor neuron disease, whose pathogenesis is still unknown. The pathological process stems from a degeneration of the peripheral motor neurons of the brainstem and spinal cord, which leads to denervation and consequent atrophy of the correspondent muscular fibers. In the regions where occurs muscular fibers’ thinning, occurs deposition of lipid pigments and other substances, as so astroglial and microglial proliferation. In the beginning of the pathological process, some muscular groups are affected, leading to an unspecific asymmetrical muscular weakness. As the disease progresses, larger is the number of affected muscles groups, eventually compromising the respiratory muscles and leading to death. The phenomenon inducing neuronal destruction has not been enlightened, that makes this fast progression pathology a huge problem in the Neurology field. Due to the absence of a specific etiology, exogenous risk factors are being increasingly explored as causative agent of the disease. The ongoing discovery of genes mutations in ALS patients increases genetic factors’ importance in the pathogenesis of the disease, mainly because it seems to be directly linked to several processes responsible for motor neuron destruction. The mechanisms leading to degeneration are several, among them there’s the oxidative stress process, glutamate excitotoxicity, protein aggregation dysfunction, astrocyte dysfunction, neurovascular alterations, inflammatory processes as so neurofilament and microtubule dysfunction. None of this processes act isolated or independently and many studies suggests the existence of a complex mechanism in constant interplay, culminating in neuronal damage and death. The scarce knowledge of ALS’ physiopathology difficult the elaboration of efficient therapeutic strategies intended to slow disease progress. At the moment, only Riluzole shows some significant results, although with just a modest lengthening of the patient’s survival in months. In the course of the studies many aspects of ALS had been discovered, clearing the way to new hypothesis and possibilities for deeper studies.
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Puigdomenech, Poch Maria. « Development of therapeutic strategies for amyotrophic lateral sclerosis ». Doctoral thesis, Universitat Autònoma de Barcelona, 2020. http://hdl.handle.net/10803/670740.
Texte intégralRésumé :
L’esclerosis lateral amiotròfica (ELA) és una malaltia neurodegenerativa devastadora, per la qual actualment no existeix cap tractament. L’ELA es caracteritza per la pèrdua progressiva de motoneurones (MN) tan superiors com inferiors i la consegüent atrofia muscular. A dia d’avui es desconeix el mecanisme molecular específic que promou la mort de les MN, però s’ha relacionat amb diferents processos que inclouen tant les MN com les cèl·lules del voltant com pot ser l’estrès oxidatiu, la inflamació o l’agregació de proteïnes com la superòxid dismutasa 1 (SOD1). En aquesta tesis nosaltres proposem dues estratègies terapèutiques per L’ELA: incrementar l’eficiència de silenciament de la proteïna mutada SOD1 mitjançant teràpia gènica i estudiar el rol de l’àcid lisofosfatídic (LPA) com a mediador de la inflamació, en la fisiopatologia de l’ELA.
En el primer capítol, amb l’objectiu de reduir els nivells de RNA de la proteïna mutada SOD1, nosaltres administrem oligonucleòtids antisentit (ASO) conjugats a lligands específics per tal d’incrementar la seva internalització a les cèl·lules. Els resultats presentats revelen la eficient internalització d’aquesta teràpia a neurones i cèl·lules glials. A més, la conjugació del ASO amb el lligand DCPP redueix de manera més eficient els nivells de RNA de SOD1 que no pas els ASO no conjugats. Tot i això l’administració del ASO conjugat al lligand DCPP en els ratolins SOD1G93A, el model experimental de ALS, no presenten afectes terapèutics.
Pel que fa el segon capítol, com que la inflamació és un tret comú de la majoria de les condicions neurològiques i sabent que el receptor LPA2 contribueix en la fisiopatologia de la lesió medul·lar, ens preguntem si l’LPA podria contribuir en la fisiopatologia de l’ELA. Per això vam creuar ratolins nuls pel receptor LPA2 amb ratolins SOD1G93A. Els resultats demostren que l’absència del receptor LPA2 retarda la progressió de la malaltia i evita l’atròfia muscular en ratolins SOD1G93A.
Col·lectivament els resultats que presentem en aquesta tesis aporten nova informació que podria servir per desenvolupar estratègies pel tractament de l’ELA.La esclerosis lateral amiotrófica (ELA) es una enfermedad neurodegenerativa devastadora, por la cual actualmente no existen ningún tratamiento. La ELA se caracteriza por la pérdida progresiva de motoneuronas (MN) superiores e inferiores y la consiguiente atrofia muscular. Hoy en día se desconocen los mecanismos moleculares específicos que promueven la muerte de estas MN, aunque se han relacionado con múltiples procesos que incluyen tanto las MN como las células subyacentes, tales como el estrés oxidativo, la inflamación o la agregación de proteínas como la superóxido dismutasa 1. En esta tesis nosotros proponemos dos estrategias terapéuticas para el ELA: incrementar la eficiencia del silenciamiento de la proteína mutada SOD1 mediante terapia génica y estudiar el rol del ácido lisofosfatídico (LPA) como mediador de la inflamación, en la fisiopatología del ELA. En el primer capítulo, con el objetivo de reducir los niveles de RNA de la proteína mutada SOD1, administramos oligonucleótidos antisentido (ASO) conjugados a ligandos específicos, por así incrementar su internalización a las células. Los resultados presentados revelan la eficiente internalización de esta terapia en neuronas y células gliales. Además, la conjugación del ASO con el ligando DCPP reduce de manera más eficiente que los ASO no conjugados, los niveles de RNA de SOD1 en los ratones SOD1G93A. Sin embargo, la administración del ASO conjugado con el ligando DCPP en los ratones SOD1G93A no presenta efectos terapéuticos. En el segundo capítulo, como la inflamación es un factor común en varias condiciones neurológicas y sabiendo que el receptor LPA2 contribuye en la fisiopatología de la lesión medular, nos preguntamos si el LPA podría contribuir en la fisiopatología del ELA. Por esto cruzamos ratones nulos por el receptor LPA2 con ratones transgénicos SOD1G93A. Nuestros resultados demuestran que la ausencia del receptor LPA2 retarda la progresión de la enfermedad y evita la atrofia muscular en ratones SOD1G93A. Colectivamente los resultados presentados en esta tesis aportan nueva información que podrían servir para desarrollar estrategias para el tratamiento de la ELA.
Amyotrophic lateral sclerosis (ALS) is a devasting neurodegenerative disorder with no effective treatment currently available. ALS is characterized by the progressive loss of both upper and lower motoneuron (MN) and the consequent muscle atrophy. Nowadays the specific molecular mechanism that underline the MN death is unknown, however has been related several dysfunction mechanisms in MNs and the surrounding cells, such: oxidative stress, inflammation or aggregation of aberrant proteins like superoxide dismutase 1 (SOD1). In this thesis we propose two therapeutic strategies for ALS: increase the silencing efficiency of the mutated SOD1, by means of gene therapy and study the role of the lysophosphatidic acid (LPA) in the pathophysiology of ALS. In the first chapter, with the aim to reduce the RNA levels of the SOD1 mutated, we administrated antisense oligonucleotide (ASO) conjugated to specific ligands to increase the internalization of the molecule. The results present here reveal the efficient internalization of the therapy in neurons and glia cells. Furthermore, the conjugated- ASO with the ligand DCPP reduce more efficiently than the unconjugated ASO, the SOD1 RNA levels in the SOD1G93A mice, an experimental model of ALS. However, the administration of the conjugated-ASO with the ligand DCPP in the SOD1G93A mice, does not present therapeutic effects. In the second chapter, since inflammation is a hallmark of most neurological conditions and LPA2 has been reported that contribute to the pathophysiology of spinal cord injury, we wonder if LPA could be involved in the pathophysiology of ALS. To assess whether activation of LPA2 contributes to ALS, we crossed LPA2 null with SOD1G93A mice. Our results reveal that the absence of LPA2 delays onset and progression of the disease and prevent the muscle atrophy in ALS mice. Collectively the results presented here provide more novel data that could underline new therapeutic strategies for ALS.
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Bamberg, Christopher Ryan. « Lateral Movement of Unbraced Wood Composite I-Joists Exposed to Dynamic Walking Loads ». Thesis, Virginia Tech, 2009. http://hdl.handle.net/10919/31977.
Texte intégralRésumé :
The research summarized in this thesis is comprised of an experimental analysis of the mechanical behavior of a wood composite I-joist with different bracing configurations exposed dynamic walking loads. Three 16 in. deep GPI® 65 I-joists were simply supported and laid parallel to each other, while the bracing was attached to the top flange. Five different brace stiffnesses were used: zero stiffness (control), 1.2 lb/in., 8.5 lb/in., 14.0 lb/in. and infinitely stiff. Two different brace configurations were used: one-quarter of the span length (60 in.) and one third the span length (80 in.). The dynamic walking loads consisted of human test subjects attached to a safety platform walking across the I-joist at a designated pace. Experimental results for this research consisted of the I-joistâ s lateral accelerations, lateral displacements and twist. An Analysis of Covariance (ANCOVA) was used for the statistical analysis of the results and was performed for each measurement. The statistical analysis determined the effects of different bracing configurations, stiffnesses, measurement locations as well as test subjectsâ weight and occupation.
Test results and observed trends are provided for all test configurations. Lateral displacement and twist experienced the same trend throughout the experiment: as brace stiffness increased, lateral displacement and twist decreased. This correlated with basic beam theory and bracing fundamentals. It should be noted that as the stiffness increased, the effect on lateral displacement and twist response decreased.
However, the trend for lateral displacement and twist was not observed for the lateral accelerations. The 1.2 lb/in. brace stiffness had much larger lateral accelerations for the 60 in. brace configuration throughout the span and were also larger at the bracing point for the 80 in. brace configuration. This could have been due to the energy applied from the springs or a natural frequency of the I-joist system could have been reached during testing. However, the other four brace stiffnesses followed the same trend as the lateral displacements and twist.
In addition, this research demonstrates a method for the measurement of lateral buckling due to worker loads. The mitigation of lateral buckling can use appropriate bracing systems. The measurements of the change in lateral buckling behavior can be used to develop safety devices and ultimately ensure the protection of construction workers.
Master of Science
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Haubrich, Alexander George Carl. « Akustoelektrischer Strom durch lateral definierte Quantenpunktkontakte ». [S.l.] : [s.n.], 2001. http://deposit.ddb.de/cgi-bin/dokserv?idn=961446056.
Texte intégral
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Haubrich, Alexander George Carl. « Akustoelektrischer Strom durch lateral definierte Quantenpunktkontakte ». Diss., lmu, 2001. http://nbn-resolving.de/urn:nbn:de:bvb:19-3157.
Texte intégral
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Chan, Kin Wa (Karl), University of Western Sydney, of Science Technology and Environment College et School of Computing and Information Technology. « Lateral electron disequilibrium in radiation therapy ». THESIS_CSTE_CIT_Chan_K.xml, 2002. http://handle.uws.edu.au:8081/1959.7/538.
Texte intégralRésumé :
The radiation dose in radiation therapy is mainly measured by ion chamber. The ion chamber measurement will not be accurate if there is not enough phantom material surrounding the ion chamber to provide the electron equilibrium condition. The lack of electron equilibrium will cause a reduction of dose. This may introduce problems in treatment planning. Because some planning algorithms cannot predict the reduction, they over estimate the dose in the region. Electron disequilibrium will happen when the radiation field size is too small or the density of irradiated material is too low to provide sufficient electrons going into the dose volume. The amount of tissue required to provide electron equilibrium in a 6MV photon beam by three methods: direct calculation from Klein-Nisina equation, measurement in low density material phantom and a Monte Carlo simulation is done to compare with the measurement, an indirect method from a planning algorithm which does not provide an accurate result under lateral electron disequilibrium. When the error starts to happen in such planning algorithm, we know that the electron equilibrium conditions does not exist. Only the 6MV photon beam is investigated. This is because in most cases, a 6MV small fields are used for head and neck (larynx cavity) and 6MV fields are commonly used for lung to minimise uncertainity due to lateral electron at higher energies.Master of Science (Hons)
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Wu, Zhou. « Collaborative lateral maps on the Web ». Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape7/PQDD_0016/MQ49474.pdf.
Texte intégral
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Chan, Kin Wa. « Lateral electron disequilibrium in radiation therapy / ». View thesis, 2002. http://library.uws.edu.au/adt-NUWS/public/adt-NUWS20040507.164802/index.html.
Texte intégralRésumé :
Thesis (M.Sc.) (Hons)-- University of Western Sydney, 2002."A thesis submitted in fulfillment of the requirements for the Degree of Master of Science (Honours) in Physics at the University of Western Sydney" "September 2002" "Kin Wa (Karl) Chan of Medical Physics Department of Westmead Hospital and the University of Western Sydney"-- t.p. Bibliography: leaves 100-105.
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Linder, Tomas, Torbjörn Löfqvist, Coppel Ludovic Gustafsson, Magnus Neuman et Per Edström. « Lateral light scattering in fibrous media ». Mittuniversitetet, Avdelningen för naturvetenskap, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-18657.
Texte intégralRésumé :
Lateral light scattering in fibrous media is investigated by computing the modulation transfer function (MTF) of 22 paper samples using a Monte Carlo model. The simulation tool uses phase functions from infinitely long homogenous cylinders and the directional inhomogeneity of paper is achieved by aligning the cylinders in the plane. The inverse frequency at half maximum of the MTF is compared to both measurements and previous simulations with isotropic and strongly forward single scattering phase functions. It is found that the conical scattering by cylinders enhances the lateral scattering and therefore predicts a larger extent of lateral light scattering than models using rotationally invariant single scattering phase functions. However, it does not fully reach the levels of lateral scattering observed in measurements. It is argued that the hollow lumen of a wood fiber or dependent scattering effects must be considered for a complete description of lateral light scattering in paper.PaperOpt
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Gray, Louise Elizabeth. « A novel electrochemical lateral flow immunoassay ». Thesis, University of Strathclyde, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.501682.
Texte intégralRésumé :
Cardiac surgery with cardiopulmonary bypass (CPB) can trigger systemic inflammatory response syndrome (SIRS) in patients. Pro-inflammatory cytokines lL-6 and IL-8 are reported as particular markers in blood of the inflammatory •espouse to CPB. It would be useful to measure the inflammatory response in the surgical theatre in real/near real time to improve the effectiveness and timings for interventions which may counteract any undesirable inflammatory response. Currently, Enzyme Linked Immunosorbent Assays (ELISAs) and similar systems are used in the central laboratory to measure inflammatory markers however they do not provide results within the appropriate timescale for rapid intervention. Consequently other approaches to assay provision at point of care must be considered. This thesis is concerned with the design, fabrication and characterisation of a prototype, electrochemical, lateral flow system opening a new approach to rapid, point of care (POC), quantitative monitoring of inflammatory markers.
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Merican, Azhar Mahmood. « The lateral retinaculum of the knee ». Thesis, Imperial College London, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.520953.
Texte intégral
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Dailey, Ryan T. « LEADING FACTORS DETERMINING LATERAL TRANSFER SUCCESS ». Monterey, California. Naval Postgraduate School, 2013. http://hdl.handle.net/10945/32808.
Texte intégralRésumé :
This study examines the characteristics of officers applying to and being selected by lateral transfer boards using biannual redesignation data from November 2010 through November 2012. The lateral transfer board reviews approximately 500 applicants each year. The majority of the Restricted Line designators rely on lateral transfer boards as their primary means of accessing new officers, where the average applicant is an O-3, male, and is a surface warfare officer (1110). Although the applicants are moderately different at each board, the aggregate selection rate is 40 percent. A probit analysis suggests that officers who are most likely to be successful at redesignating are Hispanic and O-4, as well as Limited Duty Officers. The regression results indicate that there is no gender difference in selection but senior pay grades are selected at a higher rate, where Information Professional and Foreign Area Officer communities currently have the greatest demand for officers at the lateral transfer boards. Additionally, Surface Warfare provides the greatest supply of applicants on average, but holding all else equal, an officer is less likely to be selected if he or she applies as a surface warfare officer.
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Xiao, Qiuwu. « Lateral Torsional Buckling of Wood Beams ». Thèse, Université d'Ottawa / University of Ottawa, 2014. http://hdl.handle.net/10393/31174.
Texte intégralRésumé :
Structural wood design standards recognize lateral torsional buckling as an important failure mode, which tends to govern the capacity of long span laterally unsupported beams. A survey of the literature indicates that only a few experimental programs have been conducted on the lateral torsional buckling of wooden beams. Within this context, the present study reports an experimental and computational study on the elastic lateral torsional buckling resistance of wooden beams.
The experimental program consists of conducting material tests to determine the longitudinal modulus of elasticity and rigidity modulus followed by a series of 18 full-scale tests. The buckling loads and mode shapes are documented. The numerical component of the study captures the orthotropic constitutive properties of wood and involves a sensitivity analysis on various orthotropic material constants, models for simulating the full-scale tests conducted, a comparison with experimental results, and a parametric study to expand the experimental database.
Based on the comparison between the experimental program, classical solution and FEA models, it can be concluded that the classical solution is able to predict the critical moment of wood beams. By performing the parametric analysis using the FEA models, it was observed that loads applied on the top and bottom face of a beam decrease and increase its critical moment,respectively. The critical moment is not greatly influenced by moving the supports from mid-span to the bottom of the end cross-section.
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Keddie, J. R. « Swollen lateral roots in the Cyperaceae ». Thesis, University of Nottingham, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.355438.
Texte intégral
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Flowers, Joanna Mary. « Molecular studies in amyotrophic lateral sclerosis ». Thesis, King's College London (University of London), 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.397027.
Texte intégral
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Stefanou, Georgios Konstantinos. « Transport properties of lateral spin valves ». Thesis, University of Leeds, 2017. http://etheses.whiterose.ac.uk/20697/.
Texte intégralRésumé :
The current study is focused on the investigation of the spin and heat properties of a Permalloy/silver/Permalloy, Permalloy/silver (doped with Iron)/Permalloy and Vanadium/silver/Vanadium spin valves in a lateral geometry. The presence of a downturn in the spin-signal of these lateral spin valves at low temperatures, below 30 K, can be avoided by depositing the Ag at a faster rate. This will promote a better microstructure that seems to have a crucial role in systems with very low or no magnetic impurities. A small part of the report is dedicated to test the two different behaviours of the spin signal that have been suggested in the literature, in the case of spin transport through an oxidised normal metal channel. According to literature, it would either remove the downturn of the spin signal at low temperatures, or form one. Our devices exhibited no downturn below 30 K, but by oxidising them, did not lead to the creation of it. By doping the normal metal channel with a dust layer of magnetic impurities (MIL) one would expect that by increasing scattering centers the spin signal and spin diffusion length would decrease no matter where the MIL would be. Interestingly that was not confirmed, as not only the spin signal and diffusion length vary depending on the position of the MIL in the NM channel, but also in the occasion of the device where the MIL was place right in the middle of the NM channel. At temperatures above 70 K the spin signal presented was bigger than that of the reference device. Moreover, the spin diffusion length presented in the particular set of devices, exceeded that of the reference set of devices for temperatures higher than 140 K. Finally, thermal effects were also expected to get picked up during the measurements as in order to create the spin accumulation, a charge current of 500 μ A is driven through the resistive Permalloy injector. That would give rise to Joule heating and Peltier effect once it reaches the Permalloy/silver junction due to the mismatch of the Peltier coefficients. Heat would then diffuse along the silver channel and through the substrate and would be detected in the second silver/Permalloy junction. The latter acted as a thermocouple and due to the difference in their Seebeck coefficients the temperature difference that was picked up, was converted to potential difference. The Scanning Thermal Microscopy technique was employed to image these effects. Based on the results of the technique, an analytical model that can predict the injector and detector junction temperature increase from that of the substrate was developed. In addition to that, since the voltage output is proportional to the product of the effective Seebeck coefficient with the temperature difference, the detector voltage could be predicted. To test the model a simple system of V/Ag/V device was used to deconvolute the thermal effects avoiding having a spin accumulation in the detector signal. After that, the thermal effects arising in a Py/Ag/Py lateral spin valve were investigated. Finally, since the Peltier effect was present in the measurements, the non-local resistance, spin signal and baseline resistance were analysed as a function of current direction to find a so far not studied effect. There was a splitting in the non-local and baseline resistance across all different devices that had temperature and current dependence. To confirm that the effect was not an artefact, three cryostats, three transport sticks, two sample holders and two more systems (Py/Cu/Py and CoFe/Cu/CoFe) were studied.
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Schymick, Jennifer. « The genetics of amyotrophic lateral sclerosis ». Thesis, University of Oxford, 2009. http://ora.ox.ac.uk/objects/uuid:f68f15c2-2875-46ba-bf25-8324c1dead91.
Texte intégralRésumé :
Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease characterised clinically by rapidly progressive paralysis leading ultimately to death from respiratory failure. There is no cure for ALS and no definitive explanation for the onset and rapid progression of motor neuron degeneration. Genetics is a known risk factor for a portion of familial cases. However, the role of genetics in the commoner sporadic form of the disease is poorly understood, although numerous genes have been implicated. The primary aim of this thesis project is to uncover the genetic causes that underlie ALS. To accomplish this goal, the main focus of this thesis is to perform genome-wide association analysis of sporadic ALS using high density SNP arrays. This thesis describes the first and the largest genome-wide association studies of ALS to date. Results demonstrate that there is no single large effect susceptibility variant underlying a large proportion of ALS, such as ApoE in Alzheimer’s disease. However, the genotyping data has been made publically available and the digital nature of this data means that it is a resource that can grow with future studies. Beyond genome-wide association, this thesis describes work using linkage, haplotype and sequence analysis to investigate the genetic overlap between ALS and frontotemporal dementia. Lastly, this thesis presents a novel method for linkage analysis using high throughput SNP arrays. Ultimately, it is hoped that by uncovering the genes that cause ALS, such knowledge will shed light on the pathogenic mechanisms underlying motor neuron degeneration and potentially lead to new rational therapies effective in slowing or even halting disease progression.