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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.
151

Avaliação da resistência mecânica à compressão axial da poliuretana de mamona e quitosana associada a cimento de fosfato de cálcio no preenchimento de falhas ósseas do terceiro metacarpiano de equinos / Mechanical evaluation of strength of ricinus communis polyurethane and chitosan with calcium phosphate cement on filling of bone gap in equine third metacarpal bone

Rodrigo Crispim Moreira 30 May 2014 (has links)
Os equinos são animais que, quando adultos, apresentam elevado peso corpóreo e ossos bastante resistentes para sustentar esse peso. Dessa forma, para que ocorra fratura nos ossos do cavalo é necessário um trauma de elevada energia resultando em fraturas cominutivas, que podem formar falhas ósseas impedindo o contato entre os fragmentos ósseos, o que compromete a estabilidade e resistência da osteossíntese. Devido à complexidade desse tipo de fraturas e aos implantes disponíveis apresentarem baixa resistência para o uso nessa espécie e devido a seu comportamento, o tratamento de fraturas em equinos apresenta baixos índices de sucesso. Dessa maneira, o uso de um material osteocondutor com resistência mecânica para o preenchimento dessas falhas poderia elevar a resistência da osteossíntese, levando a melhores índices de sucesso na correção dessas fraturas. O presente estudo teve como objetivo a avaliação biomecânica em laboratório de dois biomateriais substitutos ósseos no preenchimento de falha óssea. Para isso foram utilizados 30 ossos terceiro metacarpiano de equinos que foram submetidos a osteossíntese com placa LCP em sua face dorsal e criada uma falha óssea transversal completa de um centímetro na diáfise média. Dez dessas peças foram submetidas a ensaios biomecânicos não destrutivos até a carga de 1000N, onde foram avaliadas a rigidez, as deformações da peça inteira, da placa e do osso individualmente em diferentes regiões. As outras 20 dessas peças foram submetidas a ensaios destrutivos, onde foram avaliadas a carga e deformação suportada no limite elástico e no ponto de ruptura. Dessa forma, pôde-se observar que houve aumento na rigidez de 699,39N/mm para 2905,38N/mm e 4274,93N/mm devido ao preenchimento da falha com poliuretana de mamona e quitosana, respectivamente. A peça inteira teve sua deformação diminuída de 1,73mm para 0,5mm e 0,35 com carga de 1000N, devido ao preenchimento da falha com poliuretana de mamona e quitosana, respectivamente. A placa teve sua deformação diminuída de 2260,64µd para 320,25µd pelo preenchimento da falha com poliuretana de mamona e para 89,88µd com o preenchimento com quitosana durante a aplicação de 1000N. O osso próximo à falha sofreu maiores deformações tanto com poliuretana de mamona quanto com quitosana, contudo não apresentou maiores deformações em região distante da falha. A peça inteira teve aumento da carga suportada em seu limite elástico de 1008N para 8804N apenas com o preenchimento da falha com quitosana. A peça inteira teve sua deformação diminuída de 1,64mm para 1,26 no limite elástico apenas devido ao preenchimento da falha poliuretana de mamona. A peça inteira teve aumento da força suportada no momento de ruptura de 1660N para 15187N e 11012N com o preenchimento da falha com poliuretana de mamona e quitosana, respectivamente. A peça inteira teve sua deformação máxima no ponto de ruptura diminuída de 5,4mm para 2,16mm apenas com o preenchimento da falha com quitosana. / Adult horses are heavy animals equipped with bones strong enough to support their body weight. High energy trauma is required to produce comminuted fractures, where bone loss may prevent proper fracture reduction and compromise osteosynthesis resistance and stability. In horses, aside from behavioural issues, low success rates associated with comminuted fracture resolution may be due to the complexity of such fractures or the low resistance of bone implants. Therefore, osteoconductive biomaterials with good mechanical resistance would potentially benefit treatment outcomes. This ex vivo study evaluated the biomechanical behaviour of two bone surrogate biomaterials in experimental third metacarpal fractures in horses. Thirty equine third metacarpal bone specimens were submitted to dorsal LCP (locking compression plate) osteosynthesis following creation of a transverse 1 cm wide middiaphiseal defect. Defects were filled either with Ricinus communis polyurethane or calcium phosphate cement-chitosan composite. Ten specimens were submitted to non-destructive biomechanical testing under 1000N maximum load; construct stiffness, construct deformation and isolated deformation of LCP and third metacarpal bone in different regions were evaluated. The remaining 20 specimens were submitted to destructive biomechanical testing; maximum load and deformation within the elastic limit, and to failure were documented. Bone defect repair with RCP or CPC-chitosan composite increased construct stiffness from 699,39N/mm to 2905.38N/mm and 4274.93N/mm and decreased construct deformation under 1000N from 1.73mm to 0,5mm and 0.35 respectively. LCP deformation under 1000N decreased from 2260.64d to 320.25µd and from 2260.64µd to 89.88d following filling of the bone defect with RCP or CPC-chitosan composite respectively. Bone deformation around the defect increased following treatment with RCP or CPC-chitosan composite. However bone deformation away from the defect remained unchanged. Maximum load within the elastic limit increased from 1008N to 8804N when the experimental defect was filled with chitosan composite. Conversely, construct deformation within the elastic limit decreased from 1.64mm to 1.26mm following treatment with RCP. Maximum load to construct failure increased from 1660N to 15187N and 11012N following bone defect repair with RCP or calcium phosphate cement-chitosan composite respectively. However, construct maximum deformation decreased from 5.4mm to 2.16mm when calcium phosphate cement-chitosan composite was used.
152

Evaluation of ricinus communis semi-purified extracts' potential as anti-metastatic agents using metastatic breast cancer (MCF-7) cancer cells

Mabasa, Rixile Forever January 2017 (has links)
Thesis (MSc. (Biochemistry)) -- University of Limpopo, 2017 / The malignancy of cancer cells is responsible for the high death rate in patients diagnosed with metastatic cancers. Medicinal plants represent a reservoir of bioactive compounds that can be useful in the management of cancer. In this study, semi-purified extracts of Ricinus communis leaves were evaluated for their potential to serve as an anti-metastatic agent by using in vitro assays that tested their effects on a number of processes related to metastasis. The exhaustive extraction procedure was employed to generate the crude acetone extracts of R. communis leaves. The crude extracts were then subjected to solvent-solvent fractionation to yield six semi-purified extracts (n-butanol, Chloroform, Ethyl-acetate, n-hexane, Methanol + H2O and H2O). Thin layer chromatography (TLC) was done to determine the phytochemical composition of the semi-purified extracts as well as their antioxidant potential. Non-polar fractions showed to have a diverse mixture of phytochemicals with, however, very limited antioxidant activity. On the other hand, polar fractions showed to have phytochemical compounds with strong antioxidant potential. TLC guided the selection of n-hexane and n-butanol as fractions of great phytochemical diversity and antioxidant activity, respectively. The selected fractions were then assessed for their effect on the viability of normal fibroblasts (BUD-8) and breast (MCF-7) cancer cells using the MTT assay. The n-butanol fraction was shown to significantly decrease the viability of BUD-8 at concentrations above 200 µg/ml. The n-hexane fraction, however, showed to significantly affect the viability of the cells even at lower concentrations. On the positive side, the reduced viability of BUD-8 cells after exposure to both fractions was followed by an increase in cell proliferation after 24 hours suggesting that the extracts exhibited cytostatic rather than cytotoxic effects. Treatment of MCF-7 cells with different concentrations (100-500 µg/ml) of the fractions showed a dose- and time-dependant decrease in cell viability. Hoechst stain also confirmed the non-toxicity of the fractions to MCF-7 cells at 100 and 200 µg/ml. The fractions also showed to possess free radical scavenging activities by reducing the amount of intracellular ROS as demonstrated by the DCFH-DA fluorescent assay. Fluorescence intensity was strongly reduced in cells treated with the fractions and elevated in H2O2-treated and untreated MCF-7 cells. The effect of the fractions on metastasis was assessed by determining their effects on MCF-7 cell migration, attachment and invasiveness using wound healing assay, adhesion assay and Boyden chamber invasion assay, respectively. The wound healing assay showed the fractions to have strong inhibitory activities on the migration of MCF-7 cells. The xii ability of the cells to attach to cell culture treated plates was also greatly reduced in cells treated with the fractions. The n-butanol fraction was demonstrated to exhibit a time- and dose-dependent inhibition on MCF-7 cell invasion by reducing the cells’ capability to penetrate through the matrigel matrix to the bottom of the porous membrane. Gelatin-zymography was done to assess the effect of the n-butanol fraction on activity of MMP-2 and MMP-9. The fraction showed to completely inhibit the gelatinolytic activity of MMP-2 and no band corresponding to the molecular weight of MMP-9 was observed, suggesting that MCF-7 cells produce undetectable levels of MMP-9. The n-butanol fraction further showed to down-regulate the expression of a range of proteins such as MMP-9, uPA, VEGF, TGF-β1 implicated in metastasis and angiogenesis determined using the human angiogenesis antibody array kit. This study demonstrated that the fractions of R. communis extracts have the ability to inhibit major processes of the metastatic cascade by down-regulating the expression of proteins relevant to metastasis. Thus, the fractions can be considered as potential anti-metastatic agents functional in the regulation and/or treatment of malignant of cancers. / National Research Foundation (NRF)
153

Average Free-Running Period in Spider (Frontinella communis) Peaks and Desynchronizes Throughout its Active Season

Crain, Shae, Jones, Thomas, Moore, Darrell, 2346742 12 April 2019 (has links)
An organism’s circadian clock exists as a self-regulating oscillator that can synchronize with its surroundings. This manifests as physiological and behavioral output which can anticipate changes in environment. These rhythms may even persist internally and are known to oscillate at a period (tau) of around 24 hours even in the absence of external cues. In the laboratory, such rhythmic output is known as a free-running period (FRP). Given that circadian rhythms are distributed in a number of taxa as well as their tendency to oscillate along with the solar day, it has been suggested that they result from natural selection. The argument that tone’s clock is adaptive is based on how it is advantageous: the clock instills temporal order among physiological processes as well as enabling one to anticipate external cues. Losing that order in one’s clock has also been associated with a number of metabolic and neurological pathologies. Along with adaptive significance, it has been surmised that an internal clock which synchronizes with one’s surrounding environment is beneficial to an individual. An organism whose free-running period closest matches the rhythmic output of its external environment will exhibit a higher relative fitness as compared to those whose periods deviate from 24 hours. This forms the basis of the ‘circadian resonance hypothesis’. Circadian resonance has been examined in a number of species, from Cyanobacteria to mammals. Collectively, experimental results have supported the rationale that an individual does best when its internal clock resonates with the 24 hour day. The bowl and doily spider, Frontinella communis, not only has its own endogenous rhythm (free-running period), it exhibits an average free-running period of 28.26 hours, deviating from a usual period of ~24 hours. Keeping in mind the circadian resonance hypothesis, an internal clock with such an extreme deviation from the 24 hour day should prove detrimental to one’s overall health. Despite this, Frontinella communis not only has a long clock; among the species, their clocks also appear to be highly variable, FRPs ranging from ~24 to ~33 hours. This study monitored locomotor activity of Frontinella communis to examine whether its free-running period, on average, remained the same throughout its active season (May-September). It was found that average free-running period in F. communis varied significantly over a five-month period. Average FRP appears to peak in June followed by a steady, linear decline as the season continues. A variety of organisms have been shown to exhibit seasonal responses that allow them to cope with environmental change. It is not known whether the change in Frontinella’s FRP is such an advantage or is merely coincidental. Any free running period detected under the alpha level of 0.05 was not ruled significant. Along with the rise and fall of average FRPs, the presence of FRP deemed significant was found to decline as the season ended- 42% of individuals (n= 19) reported as arrhythmic. While age has been found to correlate with circadian desynchrony in other taxa (rats, humans), an association in Frontinella remains to be tested.
154

DNA degradation and repair in Escherichia coli following UV irradiation/

Fong, Kenneth Shui-yuen January 1977 (has links)
This document only includes an excerpt of the corresponding thesis or dissertation. To request a digital scan of the full text, please contact the Ruth Lilly Medical Library's Interlibrary Loan Department (rlmlill@iu.edu).
155

Digital Storytelling: The Application of Vichian Theory

Pierotti, Karen 24 March 2006 (has links) (PDF)
Storytelling is often looked at as something archaic or something that simpler cultures engage in. However, in our sophisticated and highly technological world storytelling swirls about us though we may not always recognize it. This thesis looks at the phenomenon of digital storytelling that functions to create community on the Internet. In order to ground this phenomenon in theory, I examine the works of Giambattista Vico, the 18th-century Neapolitan philosopher/rhetorician, who lived on the cusp of the Renaissance and the Age of Enlightenment. Furthermore, as a teacher of rhetoric to youth, Vico admonished young people to study the arts of poetry, painting, and oratory. These three arts are part of digital storytelling with the story line, visuals, and voice over. Digital storytelling, therefore, reaches more people because these arts are easily understood and accepted by people of all ages and education. Marshall McLuhan, the 20th-century Canadian scholar was an eclectic critic of technology and culture who anticipated the Internet. McLuhan used Vichian theory as the basis for some of his writings on technology. My study synthesizes and makes connections between McLuhan's writings on technology and the particular technology of digital storytelling. The new technologies bring back a secondary orality as well as more visual communication such as the radio and television in a print saturated culture. Today we are living in a world where writing, the spoken word and music, and visual images blend together in the digital milieu of the Internet. Digital storytelling is just one way that technology is being used to enhance an ancient genre. As one of its goals is to create community, this genre is trying to achieve what McLuhan suggested in the coming together of a global village.
156

The Origin of the O-methyl and the N-methyl Groups in the Alkaloid Ricinine

Dubeck, Michael 07 1900 (has links)
The origin of the 0 -methyl and the N -methyl group in the alkaloid ricinine has been determined. Carbon 14 labelled sodium bicarbonate sodium formate and C14 methyl labelled L-methionine and choline were administered to growing seedlings of Ricinus communis which elaborate the alkaloid ricinine. Methionine was the only metabolite that produced C14 activity in the alkaloid. The activity was located entirely in the methyl groups and the specific activity of the O-methyl and N-methyl group was found, within experimental error, to be identical. / Thesis / Master of Science (MSc)
157

Identification and mapping of genomic regions controlling fire blight and psylla resistance and hybrid necrosis in pear / Identification et cartographie de régions du génome contrôlant la résistance au feu bactérien et au psylle et la nécrose hybride chez le poirier

Montanari, Sara 03 July 2015 (has links)
Le feu bactérien et le psylle causent d’importantes pertes économiques dans les zones de production du poirier dans le monde entier. Le développement de nouvelles variétés de poirier résistantes à ces bio-agresseurs constitue un enjeu majeur dans le cadre d’un programme de lutte intégrée. L’objectif de ce projet de thèse est l'étude du déterminisme génétique de la résistance vis-à-vis de ces deux bio-agresseurs. La thèse a été réalisée dans le cadre d’une collaboration internationale entre Fondazione Edmund Mach (Italie), Institut de Recherches en Horticulture et Semences (France) et Plant & Food Research (Nouvelle-Zélande). Une descendance interspécifique de poirier T003 x ‘Moonglow’ a été développée avec pour objectif de cumuler les résistances au feu bactérien et au psylle provenant de variétés asiatiques et européennes de Pyrus. Deux cartes génétiques ont été élaborées pour T003 et ‘Moonglow’ sur la base de marqueurs SNP (Single Nucleotide Polymorphism) et SSR (microsatellite), et la cartographie de QTLs (Quantitative Trait Loci) a permis de démontrer le déterminisme polygénique de la résistance à ces bio-agresseurs. Une sélection assistée par marqueurs (MAS) peut donc être engagée pour ces deux caractères. Des incompatibilités génétiques ont aussi été observées dans une partie de la descendance, ce qui a permis de cartographier pour la première fois chez le poirier les zones du génome liées au phénomène de « nécrose hybride ». Le développement de marqueurs liés aux gènes létaux devrait permettre aux sélectionneurs d’éviter les combinaisons incompatibles en croisement qui peuvent impacter certains caractères agronomiques co-ségrégant avec ces gènes létaux. / The goal of this PhD project was to study the genetic architecture of pear resistance to two of its most significant diseases and pests, fire blight and psylla, which cause severe yield losses in all the main pear production regions worldwide. The development of new pear varieties with resistance against these two biotic stresses is of major interest for Integrated Pest Management. This project was designed in a joint collaboration among Fondazione Edmund Mach (Italy), Institut de Recherches en Horticulture et Semences (France) and Plant & Food Research (New-Zealand). The interspecific pear F1 progeny T003 x ‘Moonglow’ was developed with the purpose of cumulating resistances to fire blight and psylla deriving from Asian and European pear cultivars. Single nucleotide polymorphism (SNP) and simple sequence repeat (SSR)-based genetic maps were built for T003 and ‘Moonglow’. Quantitative Trait Loci (QTLs) were detected for the resistances, demonstrating their polygenic nature. Marker-assisted selection (MAS) can now be applied for these two traits. Furthermore, the segregating population exhibited genetic incompatibilities, and the genomic regions associated with hybrid necrosis were mapped for the first time in pear. Development of molecular markers linked to the lethal genes should allow breeders to avoid crosses leading to incompatible combinations that could affect the expression of important agronomic traits co-segregating with these genes.
158

Amino acid and glucose conjugates of a phenylpyrrole compound : synthesis, systemicity and biological properties / Conjugués entre un dérivé phénylpyrrolique et un aminocide ou le glucose : synthèse, systémie et propriétés biologiques

Wu, Hanxiang 07 April 2017 (has links)
Le but de notre travail est de développer une stratégie de vectorisation pour conférer la mobilité phloémienne aux produits agrochimiques en appliquant le concept de prodrogue dans l'élaboration de composés phytopharmaceutiques. Le fenpiclonil, fongicide non systémique de la famille des phénylpyrroles, a été choisi comme composé parent modèle et modifié en l'associant à un acide alpha-aminé ou à un monosaccharide.La mobilité phloémienne des conjugués entre le fenpiclonil et les acides L ou D-glutamique ou le D-glucose (D-GFC) a été évaluée chez des plantules de ricin. Le test de systémie a montré que le L-aminoacide était nettement plus favorable à la mobilité phloémienne que l'acide D-aminé ou le D-glucose. Les résultats suggèrent que le conjugué fenpiclonil/L-aminoacide est reconnu et manipulé par un système de transport d'acide aminé stéréospécifique énergisé par la force proton-motrice. Des expériences complémentaires ont montré que le D-GFC était un inhibiteur puissant et sélectif de l'absorption du saccharose par les tissus foliaires et du chargement phloémien du saccharose. En raison de l'inhibition spécifique des transporteurs de saccharose (par exemple AtSUC2), le D-GFC peut être envisagé comme un nouvel outil en phloémologie.Enfin, nous avons exploré l'impact de la modification de structure de l'espaceur afin d'optimiser la stratégie de prodrogue. Après avoir introduit différentes structures d'espaceur entre le fenpiclonil et la fonction acide aminé, le conjugué qui contient un cycle triazole avec l'acide aminé comprenant la chaine la plus courte a montré la meilleure mobilité phloémienne et, par ailleurs, une systémie optimisée par rapport aux dérivés acides du fenpiclonil dans la gamme des valeurs de pH de l'apoplasme foliaire. / The purpose of our work is to develop a vectorization strategy to confer phloem mobility to agrochemicals by applying prodrug concept into agrochemical design. Fenpiclonil, a non-systemic fungicide from the phenylpyrrole family, was selected as a model parent compound and modified by associating it with an amino acid or a monosaccharide.The phloem mobility of L and D-glutamic acid and D-glucose fenpiclonil conjugates (D-GFC) was evaluated in Ricinus seedlings. The systemicity test showed that the L-amino acid promoiety was clearly more favorable to phloem mobility than D-amino acid or D-glucose. The results suggested that the transport of the L-amino acid conjugate is governed by a stereospecific amino acid carrier system energized by the proton motive force. Further investigation indicated that D-GFC was a potent and selective inhibitor of sucrose uptake by leaf tissues and sucrose phloem loading. Due to its specific inhibition of sucrose transporters (e.g. AtSUC2), D-GFC can be a candidate as a new tool in phloemology. Finally, we explored structural modifications of the spacer arm to optimize the prodrug strategy. Different structures of the spacer arm were introduced between fenpiclonil and the amino acid function. The conjugate which contains a triazole ring with the shortest amino acid chain showed the best phloem mobility and a better systemicity than fenpiclonil acidic derivatives within the pH range of the foliar apoplast.
159

Efeito de soluções experimentais de Ricinus communis, peróxido alcalino e cloreto de cetilpiridínio na superfície da liga metálica de cobalto cromo / Effect of experimental solutions of Ricinus communis, alkaline peroxide and cetylpyridinium chloride on the surface of the cobalt chromium alloy

Curylofo, Patricia Almeida 24 January 2017 (has links)
A longevidade da prótese e a saúde bucal de usuário de Prótese Parcial Removível (PPR) são muito dependentes de higiene apropriada. O objetivo deste estudo foi comparar o efeito de soluções de Ricinus communis, em diferentes concentrações, com soluções de peróxido alcalino e cloreto de cetilpiridínio, em relação à liga metálica de Cobalto Cromo (Co-Cr) que compõe a estrutura de PPR. A amostra do experimento foi composta por 55 espécimes de Co-Cr, confeccionados a partir de padrões de cera circulares (12 mm x 3 mm) obtidos a partir de uma matriz metálica. Os padrões foram fundidos, numerados aleatoriamente e divididos em 5 grupos de imersão: H2O- água deionizada (controle) (15 minutos); Rc 2%- Ricinus communis 2% (20 minutos), Rc 10% -Ricinus communis 10% (20 minutos), PA- peróxido alcalino (15 minutos) e CCP- cloreto de cetilpiridínio 0,500 mg (10 minutos). Os espécimes foram avaliados quanto à rugosidade de superfície (n=10) no início e após a simulação de 6 meses, 1, 2, 3, 4 e 5 anos tanto pelo microscópio confocal a laser (Sa, &micro;m), como também pelo rugosímetro de superfície (Ra, &micro;m). Um espécime de cada grupo foi analisado quanto à topografia de superfície (Microscopia Eletrônica de Varredura, MEV) e Espectrometria de Energia Dispersiva de Raios-X (EDS) antes e após simulação de uso por 5 anos. De acordo com os resultados obtidos (&alpha;=0,05) pela microscopia confocal (Sa), não houve diferença para o fator solução (Kruskal-Wallis); para o fator tempo (Friedman) houve diferença estatística em Rc 2% entre T0 e T1, T3, T4 e T6 (p<0,001) e em Rc 10% de T2 para T3 (p=0,007), com diminuição da rugosidade. Com o rugosímetro (Ra), houve diferença estatística (Kruskal- Wallis) para CCP que apresentou menor rugosidade em relação à Rc 10% em T1 (p=0,048) e T6 (p=0,013). Em relação ao tempo (Friedman), a água propiciou diminuição da rugosidade superficial (Ra) de T0 para T2 (p=0,013). Na análise de MEV e EDS podese verificar que as soluções não apresentaram efeitos deletérios sobre as superfícies. Conclui-se que embora tenha sido encontrada diferença estatística para a rugosidade, os resultados são clínicamentes aceitáveis. Deste modo, todas as soluções podem ser utilizadas com segurança pelo período de 5 anos. / Denture longevity and oral health of Removable Partial Denture (RPD) user are highly dependent on proper hygiene. The aim of this study was to compare the effect of solutions of Ricinus communis, in different concentrations, with solutions of alkaline peroxide and cetylpyridinium chloride 0.500 mg, in relation to the Cobalt Chromium (Co-Cr) alloy that composes the structure of RPD. The sample of the experiment consisted of 55 specimens of Co-Cr, made from circular wax patterns (12 mm x 3 mm) obtained in a metal matrix. The patterns were cast, randomly enumerated and divided into 5 immersion groups: H2Odeionized water (control) (15 minutes); Rc 2%- Ricinus communis 2% (20 minutes), Rc 10% -Ricinus communis 10% (20 minutes), PA-alkaline peroxide (15 minutes) and CCPcetylpyridinium chloride 0.500 mg (10 minutes). The specimens were evaluated for surface roughness (n = 10) at the beginning and after the simulation of 6 months, 1, 2, 3, 4 and 5 years by the laser confocal microscope (Sa, &micro;m) and by the rugosimeter of surface (Ra, &micro;m). One specimen from each group was analyzed for surface topography (Scanning Electron Microscopy, SEM) and Energy-dispersive X-ray spectroscopy (EDS) befofe and after simulation of use for 5 years. According to the results obtained (&alpha;= 0.05) by confocal microscopy (Sa), there was no difference for the solution factor (Kruskal- Wallis); For the time factor (Friedman) there was a statistical difference in Rc 2% in T0 to T1, T3, T4 and T6 (p <0.001) and Rc 10% in T2 to T3 (p = 0.007), with decrease in roughness. With the the rugosimeter (Ra), there was a statistical difference (Kruskal- Wallis) for CCP that presented less roughness in relation to the Rc 10% in T1 (p = 0.048) and T6 (p = 0.013). In relation to the time, (Friedman) the water caused a reduction of surface roughness (Ra) between T0 and T2 (p = 0.013). In the analysis of SEM and EDS it can be verified that the solutions did not present deleterious effects on the surfaces. It was concluded that although a statistical difference was found for roughness, the results are clinically acceptable. Thus, all solutions can be safely used for a period of 5 years.
160

Normalvärden och F-waves vid registrering på tibialis anterior vid undersökning av peroneus communis med elektroneurografi / Normal values and F-waves for registration on tibialis anterior for examination of peroneus communis with electroneurography

Lundström, Malin January 2019 (has links)
För att undersöka misstänkt tillklämningsneuropati i peroneus communis (PC) används elektroneurografi, där elektrisk stimulering möjliggör undersökning av nervledningshastigheter, svarsamplitud och överledningstid. Vid opålitlig registrering på extensor digitorium brevis (EDB), görs registreringen på tibialis anterior (TA). I dagsläget finns dock inga normalvärden eller standardiserad metod för registrering på TA. Syftet med studien var därför att ta fram dessa normalvärden och utveckla en metod för TA-registrering, och samtidigt jämföra de båda registreringspunkterna gällande nervledningshastighet, undersöka sidoskillnaderna vid registrering på TA och undersöka hur kroppslängden påverkade överledningstiden. Det undersöktes om s.k. F-waves kunde påvisas vid registrering på TA och i så fall hur hög svarsandelen och svarslatensen var. 22 deltagare mellan 23-59 år gamla och 154-190 cm i kroppslängd undersöktes. TA undersöktes med den aktiva registreringselektroden på muskeln där den var som störst och med referenselektroden på fotleden. Stimuleringar gjordes på laterala poplitea fossa och 110 mm ned distalt om caput fibula. EDB undersöktes enligt metodbeskrivning. Normalvärdena för TA var 2,2-5,4 mV gällande amplitud, 55-73 m/s gällande nervledningshastighet och 3,8-5,9 ms gällande överledningstid. Sidoskillnaderna var 0-1,4 mV gällande amplitud, 0-8 m/s gällande hastighet och 0-0,8 ms gällande överledningstid. De beräknade gränsvärdena visar på de små sidoskillnaderna som krävs för en klinisk betydelse. Överledningstiden kunde till 23 % förklaras av kroppslängden. Resultaten var likvärdiga med tidigare studier. Jämförelsen av nervledningshastigheten mellan registrering på TA och EDB visade en statistiskt, men inte nödvändigtvis kliniskt signifikant skillnad, med bias + 5 m/s. F-waves återfanns hos samtliga deltagare, med svarsandelen 94-100 %. F-wave svarslatensen kunde till 41 % förklaras av kroppslängden. / Electroneurography is used to examine a suspected entrapmentneuropathy in peroneus communis (PC), where an electric stimulus enables the evaluation of nerve conduction velocity, muscle response amplitude and latency. If registration from the extensor digitorum brevis (EDB) provides unreliable results, the registration can be made from tibialis anterior (TA). Currently there are no normal values available in our laboratory and no standard method regarding the registration on TA. The purpose of this study was therefore to retrieve normal values for this registration and to develop and establish a method, and also compare the different registration sites, to examine the side differences from the registrations on TA, and how the height affected the latency. It was also examined if so called F-waves could be recorded from TA, and if so, determine the response rate and latency. 22 participants between 23-59 years an 154-190 cm were examined. TA was examined with the active registration electrode on the site where the muscle was the largest and the reference electrode on the ankle. Stimulations were made on lateral poplitea fossa and 110 mm lower on distal caput fibula. EDB were examined according to established methods. Normal values for the registration on TA were 2,2-5,4 mV regarding amplitude, 55-73 m/s regarding nerve conduction velocity and 3,8-5,9 ms regarding latency. Side differences were 0-1,4 mV regarding amplitude, 0-8 m/s regarding nerve conduction velocity and 0-0,8 ms regarding latency. The calculated limits show that it only takes small side differences to have a clinical significance. The method gave equivalent results to previous studies. 23 % of the latency could be explained by height. The comparing of the nerve conduction velocity from the different registrations showed a significant statistical, but not necessarily clinical, difference, with the bias 5 m/s. F-waves were retrieved from all participants with a response rate of 94-100 %. 41 % of the F-wave latency could be explained by height.

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