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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
101

Sobre problemas associados a cones de segunda ordem / About problems related to second order cones

Detsch, Denise Trevisoli, 1983- 18 August 2018 (has links)
Orientador: Maria Aparecida Diniz Ehrhardt / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Matemática, Estatística e Computação Científica / Made available in DSpace on 2018-08-18T12:52:22Z (GMT). No. of bitstreams: 1 Detsch_DeniseTrevisoli_M.pdf: 1081241 bytes, checksum: c29e7e81ee2ecb8467802991fc75be51 (MD5) Previous issue date: 2011 / Resumo: Este trabalho teve como foco o estudo de problemas SOCP, tanto nos seus aspectos teóricos quanto nos seus aspectos práticos. Problemas SOCP são problemas convexos de otimização nos quais uma função linear 'e minimizada sobre restrições lineares e restrições de cone quadrático. Tivemos dois objetivos principais: estudar o conceito, as aplicações e os métodos de resolução de problemas SOCP, permitindo verificar a viabilidade de trabalhar com tais problemas; e verificar na prática o benefício de se utilizar uma ferramenta específica de SOCP para a resolução de problemas que se enquadram nessa classe. Para a avaliação prática utilizamos um software de otimização genérica (fmincon) e outro específico de SOCP (CVXOPT). A análise ficou concentrada nos requisitos robustez, número de iterações e variação do tempo com o aumento da dimensão dos problemas. Diante dos resultados obtidos com os testes numéricos, pudemos concluir que 'e interessante usar SOCP sempre que possível / Abstract: This dissertation focuses on the study of SOCP problems, both in its theoretical, and in its practical aspects. SOCP problems are convex optimization problems in which a linear function is minimized over linear constraints and second-order cone constraints. We had two main objectives: study the concept, applications and methods for solving the SOCP problem, making it possible to verify the feasibility of working with such problems; and to verify the practical benefits of using a SOCP specific tool for the resolution of problems of this class. The experimental evaluation used a generic optimization software (fmincon) and other SOCP specific software (CVXOPT). The analysis was concentrated on the robustness, number of iterations and time variation with the increasing scale of the problems. From results obtained with the numerical tests, we concluded that SOCP is worth to be used whenever possible / Mestrado / Matematica Aplicada / Mestre em Matemática Aplicada
102

Componentes calcináveis para implantes Cone Morse: análise da desadaptação entre pilar / implante

Levasseur, Caio Marcelus Pais 30 April 2015 (has links)
Submitted by Renata Lopes (renatasil82@gmail.com) on 2015-12-08T11:13:05Z No. of bitstreams: 1 caiomarceluspaislevasseur.pdf: 4546598 bytes, checksum: be57e1ab62ac45ae2f9ffe3e165c9e75 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2015-12-09T13:38:24Z (GMT) No. of bitstreams: 1 caiomarceluspaislevasseur.pdf: 4546598 bytes, checksum: be57e1ab62ac45ae2f9ffe3e165c9e75 (MD5) / Made available in DSpace on 2015-12-09T13:38:24Z (GMT). No. of bitstreams: 1 caiomarceluspaislevasseur.pdf: 4546598 bytes, checksum: be57e1ab62ac45ae2f9ffe3e165c9e75 (MD5) Previous issue date: 2015-04-30 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Os sistemas de implantes osseointegráveis se apresentam em um ou mais componentes, e a correta inter-relação, passividade de assentamento e resistência biomecânica, definem a resistência / vulnerabilidade do mesmo frente aos fatores bacterianos e oclusais. Objetivo: Avaliar as deformações inerentes ao processamento laboratorial dos pilares calcináveis de corpo único para o sistema de implantes Cone Morse. Materiais e métodos: Utilizou-se 20 implantes Cone Morse da marca SIN, 10 componentes protéticos calcináveis e 10 não calcináveis. Após os processos laboratoriais, os conjuntos foram submetidos à Microscopia eletrônica de varredura (MEV) da interface pilar/implante, para análise qualitativa e quantitativa da desadaptação gerada. Os conjuntos foram levados a ciclos térmicos (1.000 ciclos) e de fadiga mecânica (500.000 ciclos) e novamente foi realizada a MEV. Os resultados foram comparados através de análise estatística de Mean-Whitmann. Resultados: O grupo de teste (G1) apresentou os maiores valores iniciais, com média de 34, 55 μm e 11,17 μm, para a subdivisões A (fundição) e B (aplicação de porcelana) respectivamente. A subdivisão B do grupo teste apresentou a maior alteração pós testes, com média de 19,28 μm de aumento da desadaptação protética. As subdivisões G1.A, G2.A, G2.B mostraram tendência à diminuição da desadaptação de -1,03 μm, - 1,64 μm, e -0,49 μm, respectivamente. Pilares Cone Morse não calcináveis apresentam-se com alta estabilidade e baixa taxa de desadaptações. Para o grupo teste pode-se afirmar que o processo de fundição nitidamente criou as maiores dilatações e desadaptações das estruturas. O processo de sinterização da porcelana em teste, criou uma redução da desadaptação medida, porém esta voltou a aumentar após os testes em laboratório. Para o grupo controle, houve a manutenção das taxas de desadaptações menores ao limite de 10 μm, e com tendência de redução após os testes. Conclusão: O pilar calcinável Cone Morse de corpo único mostrou-se como desfavorável quanto à biomecânica, e o processo de fundição gerou as maiores desadaptações. / The system of dental implants present in one or more components, and the correct interrelationship, settling and passive biomechanical strength, defining the strength / vulnerability of the same to the forward occlusal and bacterial factors.Objective: To evaluate the defects associated to laboratory processing of abutments of unique body to the system of Cone Morse implants. Methods: We used 20 Cone Morse implants SIN brand, prosthetic components 10 and 10 calcinable not calcinable. After the laboratory processes the sets were subjected to scanning electron microscopy (SEM) of the pillar / implant interface, for qualitative and quantitative analysis of the generated misfit. The samples were taken to alternated thermal cycles (1000 – 50 and 550) and mechanical fatigue (500,000 - 120 N/cm2) and again was carried out by SEM. The results were compared by statistical analysis Mean-Whitmann (P>0,05). Results: The test group (G1) showed the highest initial values, averaging 34.55 and 11.17 micrometres for subdivisions A (casting) and B (porcelain application) respectively. The B subdivision of the test group showed the greatest change after tests, averaging 19.28 mm of increasing prosthetic misfit. The G1.A subdivisions, G2.A, G2.B showed a tendency to decrease the mismatch of -1.03 micrometres - 1.64 micrometres and -0.49 micrometres respectively. Pillars Cone Morse calcinable not present with high stability and low rate misfits. For the test group it can be said that the casting process clearly created the largest expansion and mismatches of structures. The porcelain sintering process under test, created a reduction of the mismatch measure, however this increased again after the tests in the laboratory. For the control group, there was the maintenance of rates of minor mismatches to 10 micrometres limit, and with downward trend after the tests. Conclusion: Cone Morse castable pillars proved to be unfavorable on the biomechanics, and the casting process generated the biggest misfits.
103

Expressão da quimiocina Ccl25 e seu receptor Ccr9 no processo de implantação embrionária em camundongos. / Expression of chemokine (C-C) motif 25 and its receptor during mouse embryo implantation.

Rodrigo Barbano Weingrill 24 August 2015 (has links)
Neste estudo foi analisada a expressão gênica e protéica, uterina e embrionária da quimiocina Ccl25 e de seu receptor Ccr9 nas fases iniciais da implantação embrionária (dias 3,5, 4,5, 5,5 e 7,5 de gestação). Por meio de reações imunohistoquímicas e de citometria de fluxo, foram identificadas as populações celulares envolvidas nesta expressão. Também, foram realizados ensaios de quimiotaxia com o silenciamento da expressão de Ccl25 (ODNs-Antisense) nas células trofoblásticas, para a avaliação das atividades desta quimocina. Nossos resultados sugerem o estabelecimento de uma comunicação embrião (células trofoblásticas) - endométrio (células do sistema immunológico), via Ccl25/Ccr9. Esses achados são relevantes para a compreensão das interações blastocisto/sistema immunológico materno no estabelecimento dos mecanismos imunoreguladores durante a implantação embrionária. / In this study, we analyzed the gene and protein, uterine and embryonic expression of Ccl25 chemokine and its receptor Ccr9 in early stages of embryo implantation (days 3.5, 4.5, 5.5 and 7.5 of gestation). By using immunohistochemistry and flow cytometric assays, cell populations involved in this expression were identified. In addition, chemotaxis assays were also performed after silencing of Ccl25 (ODNs-antisense) in trophoblast cells. . Our results suggest the establishment of an endometrium (immune cells) - embryo (trophoblast cells) dialogue via Ccl25/CCR9. These findings are relevant for understanding the interactions between blastocyst and maternal immune system in the establishment of immunoregulatory mechanisms during implantation.
104

Western White Pine: The Effect of Clone and Cone Color on Attacks by the Mountain Pine Cone Beetle

Jenkins, Michael J 01 May 1982 (has links)
The relationship between clone and cone color in western white pine, Pinus monticola Douglas, to attack by the mountain pine cone beetle, Conophthorus monticolae Hopkins, was studied in the Sandpoint Seed Orchard, Idaho. A positive relationship was shown to exist during a 5 year field evaluation. Cone beetles were found to prefer dark colored cones and to attack certain clones at a higher rate than others. Laboratory dissections did not indicate that cone color affected oviposition, brood development or brood mortality. Olfactometer experiments demonstrated that olfactory stimuli are involved in the cone beetle attack sequence. Visual cues relating to cone color may be involved in the initial long range host orientation of attacking beetles.
105

As conexões repressivas no Cone Sul (1960-1990): Terrorismo de Estado em conexão internacional / The repressive connections in the Southern Cone (1960-1990): State Terror in international connections

Silva, Jussaramar da 20 April 2017 (has links)
Submitted by Filipe dos Santos (fsantos@pucsp.br) on 2017-05-08T11:33:15Z No. of bitstreams: 1 Jussaramar da Silva.pdf: 2370521 bytes, checksum: 37bbc5a72b0346472d4366ee888da000 (MD5) / Made available in DSpace on 2017-05-08T11:33:15Z (GMT). No. of bitstreams: 1 Jussaramar da Silva.pdf: 2370521 bytes, checksum: 37bbc5a72b0346472d4366ee888da000 (MD5) Previous issue date: 2017-04-20 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / This thesis deals with the repressive connections in the Southern Cone between the 1960s and 1990s, looking at how these countries have transformed their security systems into what can be called a singular repressive system, based on the articulation between agents and unity in Modus operandi adopted among various nations of this sub-continent, creating the practice of State Terror. Such connection merged the Counterrevolutionary War Doctrine with the National Security Doctrines, both practiced by external orientation, either French, or North American; Creating an International System of Repression. The strategies and tactics adopted in the persecutory actions against the "internal enemy" prove this connection; Demonstrating the financing of National States with this practice through the creation of training centers in order to standardize such actions or with the involvement of military attachés, whose most terrifying face is evident in the extermination practices, torture and extrajudicial actions that involved The official armed forces or their illegal arms, such as paramilitaries and death squads / Esta tese versa sobre as conexões repressivas no Cone Sul entre as décadas de 1960 a 1990, verificando como esses países transformaram seus sistemas de segurança no que se pode denominar um sistema repressivo no singular, tendo como fundamento a articulação entre os agentes e a unidade no modus operandi adotado entre as diversas nações deste sub-continente, criando a prática do Terror de Estado. Tal conexão fundiu a Doutrina de Guerra Contrarrevolucionária com as Doutrinas de Segurança Nacional, ambas praticadas por orientação externa, seja francesa, seja norte-americana; criando um Sistema Internacional de Repressão. As estratégias e táticas adotadas nas ações persecutórias contra o “inimigo interno” comprovam tal conexão; demonstrando o financiamento dos Estados Nacionais com tal prática, através da criação de escolas de formação, a fim de uniformizar tais ações, ou com o envolvimento de adidos militares, cuja face mais tenebrosa se evidencia nas práticas de extermínio, torturas e ações extrajudiciais que envolveram as forças armadas oficiais ou seus braços ilegais, como paramilitares e esquadrões da morte
106

Charakterisierung von Mausmutanten als Modellsysteme für hereditäre Zapfendystropien

Stieger, Susann 27 September 2011 (has links)
Die Zapfenphotorezeptoren (ZPR) sind verantwortlich für das Scharf- und Farbensehen. Ein totaler Funktionsverlust der ZPR, welcher beim Menschen zur Achromatopsie führt, hat eine Degeneration der ZPR zur Folge. Die pathologischen Vorgänge, die zur Degeneration der ZPR führen sind noch nicht restlos entschlüsselt worden. Zur Analyse der ZPR-Degeneration werden Tiermodelle genutzt, wobei bisher nur wenige Tiermodelle vorhanden sind. Ziel dieser Arbeit ist die Untersuchung und Charakterisierung von Mausmodellen, die Mutationen in funktionell bedeutsamen Genen der ZPR tragen. Hierbei handelt es sich entweder um ein weiteres potentielles Kandidatengen für ZPR-Dystrophien, das SLC24A2 Gen, oder um das PDE6C Gen, welches als ursächlich für Achromatopsie identifiziert wurde. Die Tiere der verschiedenen Mauslinien wurden anhand ihrer Ohrkennung genotypisiert und für die verschiedenen molekularbiologischen Verfahren euthanasiert. Von den Augen wurde entweder das gesamte Auge, das eye cup, oder die Netzhaut weiterverarbeitet. Es wurde eine Methode zur Anrei¬cherung der ZPR mit fluorescence activated cell sorting (FACS) erarbeitet. Des Weiteren kamen Techniken auf der DNA-, RNA- und Protein- Ebene (PCR, RT-PCR, Klonieren, Western blot) sowie histologische und immunhistologische Techniken zur Anwendung. Die Tiere wurden in vivo mithilfe von bildgebenden Verfahren (Scanning Laser Ophthalmology (SLO)) untersucht und funktionell durch die Elektroretinographie (ERG) charakterisiert. Für diese Studie wurde die Cone-GFP (die grünes fluoreszierendes Protein in den ZPR produziert) Mauslinie zur Entwicklung der ZPR-Anreicherung eingesetzt und analysiert. Die slc24a2ENU-Maus¬mutante wurde extern hergestellt, wobei durch eine ENU-induzierte Mutagenese eine Punktmutation im slc24a2-Gen, welches für den NCKX2 Austauscher kodiert, an Position 1722 (c.1722g>t) gene¬riert wurde. Als weiteres Mausmodell wird die spontan aufgetretene Mausmutante cpfl1 (cone photo¬receptor function loss 1) untersucht, die zwei unterschiedliche Mutationen im pde6c-Gen besitzt. Durch Kreuzen dieser Mauslinien untereinander und mit der Trα -/- Mauslinie (knock-out Mutation der Stäbchen Transducin α-Untereinheit) wurden die Doppelmutanten Linien slc24a2ENUxCone-GFP, slc24a2ENUxTrα-/- und cpfl1xCone-GFP hergestellt und untersucht. Bei Cone-GFP Mäusen konnten ZPR mittels FACS angereichert und gezielt untersucht werden. In der angereicherten ZPR-Population wurde bei RT-PCR Analysen zum einen nur eine Spleißvariante des NCKX2-Austauschers detektiert, während bei RT-PCR Analysen von ganzen Augen mehrere Spleißvarianten des NCKX2-Austauschers gefunden wurden. Zum Zweiten wurden weitere Mitglie¬der der NCKX-Familie in der angereicherten ZPR-Population (NCKX-1, 4) detektiert. Bei der slc24a2ENU-Mausmutante konnte die Mutation im slc24a2-Gen sowohl auf DNA- als auch auf RNA- Ebene nachgewiesen werden, jedoch nicht auf Proteinebene. Sowohl bei morphologischen (SLO und Histologie) als auch funktionellen (ERG) Untersuchungen wurden keine Unterschiede zwischen Wildtyp und Mutante in der Retina erkannt. Mithilfe der SLO wurde bei allen Tieren eine verlängerte Persistenz der arteria hyaloidea beobachtet. Das ERG war bei der slc24a2xTrα-/- Dop¬pelmutanten gegenüber der reinen Trα-/- ohne Veränderung. Bei den slc24a2ENUxCone GFP Mäusen und den reinen Cone-GFP Mäusen konnte im Alter von einem Jahr keine Amplitude mehr im ERG gemessen werden. Bei der SLO (bei beiden Doppelmutanten) wurden bei einigen Mäusen autofluo¬reszierende Punkte, so genannte „AF-dots“ beobachtet. Eine Ursache hierfür konnte nicht erbracht werden. Vergleichende genomische DNA-Untersuchungen von Intron 4 des pde6c Gens zwischen der cpfl1-Maus und dem Wildtyp C57Bl/6 zeigten bei der cpfl1-Maus eine im Vorfeld bereits auf RNA-Ebene beschriebene 116bp Insertion als Anteil einer 1522bp großen genomischen Insertion ist. Zusätzlich wurde eine 1bp Deletion im Exon 7 des pde6c Gens bei der cpfl1-Maus detektiert (c.1042delT). Beide Mutationen bedingen eine Verschiebung des Leserasters (frame shift), das wiederum zu einem verfrühten Stopcodon führt (p.E289fsX297 und p.L348fsX362). Vergleichende RT-PCR Untersu¬chungen der pde6c Transkripte zwischen der cpfl1-Maus mit ihrem Parentalstamm BALB/c erbrach¬ten, dass beide die 116bp Insertion tragen. Bei der ERG Untersuchung der cpfl1-Maus (im Alter von drei und sechs Wochen) konnte keine ZPR-Antwort registriert werden. Bei einer vergleichenden SLO-Verlaufsstudie (3., 4., 6. und 8. Lebenswoche) zwischen der Cone-GFP und der Doppelmutanten cpfl1xCone-GFP Maus zeigte sich, dass die Anzahl der ZPR zu Beginn der Studie gleich sind, im weiteren Verlauf bei der Doppelmutante immer stärker abnehmen und mit 8 Wochen nur noch im ventralen Bereich vorhanden sind. Es konnte in dieser Arbeit gezeigt werden, dass die Cone-GFP Maus ein potentiell sehr wichtiges Mausmodell werden kann, um weiterführende Grund-lagenforschung an ZPR zu ermöglichen. Zum einen können ZPR durch FACS angereichert werden und zum anderen ist eine eindeutige und einfache Darstellung der ZPR in vivo durch die SLO-Technik möglich. Jedoch ist es wichtig, den Untersuchungszeitpunkt innerhalb der ersten 2 Monate anzusetzen, da die ZPR der Cone-GFP Maus danach fortschreitend degenerieren. Aufgrund der RT-PCR Untersuchung der NCKX-Familie in der angereicherten ZPR-Population der Cone-GFP Maus konnten weitere Mitglieder der NCKX Austauscher Familie in den ZPR identifiziert werden, wodurch die Aussage, dass der NCKX2-Austauscher die einzige Möglichkeit darstellt, um Ca2+-Ionen aus dem Außensegment der ZPR zu schleusen, relativiert werden muss. Die Slc24a2ENU-Mausmutante zeigt keinen offensichtlichen degenerativen retinalen Phänotyp. Die einzige Besonderheit stellt die sporadisch auftretende persistierende Arteria hyaloidea dar. Der bei einigen doppelmutanten Tieren auftretende retinale Phänotyp, der „AF-dots“-Phänotyp, ist möglich¬erweise auf den Stammhintergrund (C3H) zurückzuführen. Weitere Untersuchungen sind zur Klärung dieser Frage notwendig. Die cpfl1-Maus ist das erste Modell für Achromatopsie, bei dem die Pathologie durch Mutationen im pde6c-Gen ausgelöst wird. Das cpfl1-Allel besitzt zwei unterschiedliche Mutationen, die beide zu einem verfrühten Abbruch der Proteinsynthese führen. Durch RNA-Untersuchungen konnte gezeigt werden, dass die cpfl1-Maus sich nur in der 1 bp Deletion von dem Parentalstamm BALB/c unterscheidet. Jedoch scheinen beide Mutationen einen Anteil an der Herausbildung des Phänotyps der cpfl1-Maus zu haben. Im Rahmen der vergleichenden Verlaufsstudie mit Doppelmutanten cpfl1xCone-GFP wurde als pathologischer Vorgang eine Degeneration und keine Aplasie der ZPR nachgewiesen, da im Alter von 3 Wochen noch eine normale Anzahl an ZPR vorhanden ist.
107

Avaliação dimensional do espaço aéreo faríngeo em crianças com diferentes morfologias faciais por meio da tomografia computadorizada do feixe cônico /

Zinsly, Sabrina dos Reis. January 2010 (has links)
Resumo: O objetivo neste estudo foi avaliar as diferenças no espaço aéreo faríngeo em crianças com diferentes padrões faciais. Foram avaliadas as tomografias computadorizadas de feixe cônico de 98 indivíduos em crescimento, com idade média de 8,9 anos, divididas por sexo e faixa etária, e subdivididas de acordo com o padrão de crescimento (horizontal, vertical normal e produtores) e tipo de má oclusão (Classe I e Classe II). Utilizando um programa tridimensional, foram analisados o volume, área sagital, menor área de seção transversal e as dimensões ântero-posteriores da faringe superior e inferior. As dimensões ântero-posterior da faringe superior e inferior foi significativamente menor em indivíduos com Classe II em crianças na faixa etária entre 9 a 11 anos e a faringe superior em foi significativamente menor em crianças na faixa etária entre 5 e 7 anos com padrão de crescimento vertical. Porém, quando a faringe foi avaliada tridimensionalmente, não foram encontradas diferenças nas demais dimensões sugerindo que diferenças no padrão vertical e no tipo de má oclusão ântero-posterior (Classe I e II) não influenciam as dimensões da faringe. Não foi encontrado dimorfismo sexual. A região de maior constrição da faringe esteve presente mais freqüentemente na orofaringe (86%). Embora as dimensões lineares possam variar entre os diferentes padrões faciais, quando avaliadas tridimensionalmente, elas não foram influenciadas pelas diferentes morfologias faciais / Abstract: The aim of this study was to assess the differences in pharyngeal airway space in children with different facial patterns. Cone-beam computed tomography records of 98 growing patients with mean age of 8.9 years divided by sex and age groups and subdivided according to growth pattern (horizontal, normal and vertical growers) and type of malloclusion (Class I and Class II) were evaluated .Using a 3-dimensional virtual program the volume, sagital area, smallest cross section area, anteroposterior dimensions of superior and inferior pharynx were obtained. The anteroposterior linear dimensions of superior and inferior pharynx in children with 9 to11 years was significant smaller in patients with Class II relationship but in 3D evaluation differences were not found suggesting that anteroposterior malocclusion do not influence pharynx dimensions. The anteroposterior linear dimensions of superior , pharynx in children with 5 to7 years was significant smaller in patients with vertical growth pattern when compared to normal growers, but in 3D evaluation differences were not found suggesting that vertical pattern do not influence pharynx dimensions. No sexual dimorphism was found. The most constricted region of pharynx were mostly found at oropharynx(96%).Although linear dimensions can vary among different facial patterns, the 3-dimensional dimensions weren't influenced by different facial morphologies / Orientador: Luiz Cesar de Moraes / Coorientador: Weber José da Silva Ursi / Banca: Jefferson Luis OshiroTanaka / Banca: Edmundo Medici Filho / Mestre
108

Development of an opto-fluidic probe for on-line noncontact dimensional inspection and tool condition monitoring in a hazardous manufacturing environment

Xie, Tuqiang January 2000 (has links)
No description available.
109

Evaluation of Volumetric Change of Periapical Lesions After Apicoectomy as a Measure of Postsurgical Healing Utilizing Cone Beam Computed Tomography

Arasu, Eshwar 01 January 2017 (has links)
The aim of this study was to evaluate whether volumetric changes in persistent periapical lesions can be detected in follow-ups six months to five years after apicoectomy using cone-beam computed tomography. Patients with a previous treatment history of apicoectomy and for whom a pre-surgical CBCT scan was taken between November 2010 and December 2015 were invited to participate in the study. A post-surgical CBCT image of the treated tooth was obtained at the recall visit. Volumetric and linear measurements of periapical lesions on initial and postoperative CBCT images were performed using DiThreshGUI software and two calibrated examiners—a board-certified endodontist and a board-certified oral radiologist. Repeated-measures ANOVA were used to estimate the magnitude of reduction and to test for differences (at alpha=0.05). A total of 20 patients with 27 surgically treated teeth were recalled at an average interval of 37 months. Reduction in the size of lesions was observed in 24 teeth (88%); overall, the volumes significantly decreased as detected by software-assisted measurement of volume (P = .0002) and by calculation from linear measurements (P < .0001). Volumetric analysis detected a reduction of 86% in lesions while the linear-derived volume measurements yielded an average reduction of 96%. These two methods of lesion assessment were strongly correlated with one another in pre-surgical scans (r>0.88) when apical lesions are measurable.
110

Investigating treatment options for battlefield retinal laser injury

Aslam, Sher A. January 2013 (has links)
Battlefield retinal laser injury is an infrequent but potentially devastating cause of irreversible blindness. Resultant laser-induced photoreceptor death may occur by necrosis or apoptosis, the latter which is a form of programmed cell death that may be physiological or pathological. Though necrosis cannot be prevented, apoptosis may be inhibited under certain conditions. Therefore, following retinal laser injury, specific treatment aims to target apoptotic photoreceptors and may take the form of neuroprotection or cell replacement. The primary aim of this thesis was to construct an in vivo model in which to observe the effects of retinal laser exposure on cone photoreceptor apoptosis. Current methodology to determine the effects involves histological techniques and is therefore limited to being cross-sectional. An in vivo model would permit longitudinal study to observe the cone response to injury using clinically relevant applications, including fundus autofluorescence imaging. Such a construct would enable more sensitive evaluation of new therapies which would be of direct translational relevance. The secondary aim was to investigate potential therapeutic options for retinal laser injury by pharmacological means in the form of CNTF or cell transplantation. To identify the possible molecular signals involved in neurotrophic factor-induced photoreceptor cell survival, apoptotic gene expression was investigated focusing on those genes modulated by the CNTF pathway.

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