No description available.

This thesis is concerned with the structural analysis of dyestuffs in their natural solid state by the application of solid-state nuclear magnetic resonance. These dysetuffs are all derived from the phenylazobenzene group, but tautomerism can produce structural changes, which have so far been uncharacterised in the solid-state for many of the dyestuffs currently under investigation. The information obtainable from (^13)C and (^15)N chemical shifts, both isotropic and anisotropic will be applied in this structure determination. Under magic-angle spinning the anisotropic nature of solid-state interactions is partially averaged or removed. The rotational resonance technique will be presented, which reintroduces the homonuclear dipolar interaction allowing dipolar coupling constants to be measured. Second-order effects arising from the (^14)N quadrupole interaction broaden spin-1/2 lines (RDC) in such a manner that bond lengths can be determined. This RDC analysis will be applied to a series of hydrazone structures to determine the (^15)N-(^14)N bond length within the hydrazone linkage. Finally, the two-dimensional magic-angle turning experiment will be discussed and applied to both the (13)C and (^15)N nuclei for a range of dyestuffs to show that accurate shielding tensor information can be obtained from large molecules.

Remote sensing provides methods to infer vegetation information over large areas at a variety of spatial and temporal resolutions that is of great use for terrestrial carbon cycle modeling. Understory vegetation and foliage clumping in forests present a challenge for accurate estimates of vegetation structural information. Multi-angle remote sensing was used to derive and refine new information about the vegetation structure for the purpose of improving global leaf area index mapping. A field experiment with multi-angle, high resolution airborne observations over modified and natural backgrounds (understory, moss, litter, soil) was conducted in 2007 near Sudbury, Ontario to test a methodology for the background reflectivity retrieval. The experiment showed that it is feasible to retrieve the background information, especially over the crucial low to intermediate canopy density range where the effect of the understory vegetation is the largest. The tested methodology was then applied to background reflectivity mapping over conterminous United States, Canada, Mexico, and Caribbean land mass using space-borne Multi-angle Imaging SpectroRadiometer (MISR) data. Important seasonal development of the forest background vegetation was observed across a wide longitudinal and latitudinal span of the study area. The previous first ever global mapping of the vegetation clumping index with a limited eight-month multi-angular POLDER 1 dataset was expanded by integrating new, complete year-round observations from POLDER 3. A simple topographic compensation function was devised to correct negative bias in the data set cause by topographic effects. The clumping index reductions can reach up to 30% from the topographically non-compensated values, depending on terrain complexity and land cover type. The new global clumping index map is compared with an assembled set of field measurements, covering four continents and diverse biomes. Finally, inclusion of the new vegetation structural information, including background reflectivity and clumping index, gained from the multi-angle remote sensing was then shown to improve the performance of LAI retrieval algorithms over forests.

Trabajo de Investigación Requisito para optar al Título de Cirujano Dentista / Introducción Los biotipos faciales determinan características morfológicas, funcionales, craneofaciales y oclusales del sistema estomatognático, tienen valor en el diagnóstico y plan de tratamiento de diversas discrepancias craneofaciales y dentales y permiten predecir la dirección de crecimiento máxilofacial. Entre los métodos cefalométricos más usados para la determinación del biotipo facial encontramos el Polígono de Björk – Jarabak y el Vert de Ricketts. En éste último, los factores profundidad facial y eje facial, ubicados en la sínfisis mentoniana, pueden verse altamente afectados según la clase esqueletal del paciente. Esto conlleva a que los análisis cefalométricos relacionados con planos que utilizan estos puntos puedan perder aplicabilidad en el diagnóstico del biotipo facial. El presente trabajo propone una modificación al método biotipológico del Vert, eliminando los factores en cuestionamiento, estableciendo así un estudio comparativo con el Vert de Ricketts con respecto a la concordancia diagnóstica del biotipo facial con el método Polígono de Björk-Jarabak en pacientes clase III esqueletal severa. Materiales y Métodos Se utilizaron 60 teleradiografías de perfil, 52 digitales y 8 convencionales. Para los trazados y mediciones cefalométricas se trabajó con el programa computacional NemoCeph ® . Los análisis de concordancia diagnóstica fueron realizados con la prueba kappa de Cohen. Resultados La distribución biotipológica con el método Polígono Björk Jarabak fue de dolicofacial 12%, mesofacial 65%, braquifacial 23%, con Vert de Ricketts dolicofacial 22%, mesofacial 22%, braquifacial 56% y dolicofacial 55%, mesofacial 18%, braquifacial 27% con el método Vert modificado. Ambos métodos Vert 8 tuvieron una concordancia aceptable y significativa (p<0,0005) con el método Polígono de Björk Jarabak. Conclusiones Se rechaza la hipótesis de que el Polígono de Björk Jarabak tiene una mayor concordancia diagnóstica con el método Vert modificado que con el Vert de Ricketts. Al eliminar los factores cefalométricos en cuestionamiento, profundidad facial y eje facial, en la muestra predominó el biotipo dólicofacial, mientras que al ser incluidos estos factores en el análisis, la mayoría de los biotipos fueron braquifaciales, de lo cual se desprende que estos dos factores tienen una notoria influencia en el diagnóstico del biotipo.

The countersteering effect in motorcycles describes the apparent need to steer in the wrong direction in order to cause the chassis of the vehicle to lean over in the required direction just prior to executing a turn. The inherent danger with this procedure is that in a emergency situation where a motorcyclist must execute a sudden swerve to avoid a collision, the required behaviour is counterintuitive and panic may cause the rider to make the wrong initial movement thereby reducing their chance of avoiding a collision. As the importance of the countersteering effect is not taught in UK motorcycle training courses, the current work has attempted to establish whether doing so could significantly improve the ability of riders in swerve to avoid manoeuvres. An initial survey of motorcycle riders suggested some confusion about the nature of countersteering. To explore this further, four groups of riders with different levels of experience and training: novice, experienced, advanced and expert, were tested over a simple swerve to avoid course that was based on the procedure in the current UK motorcycle test. All the riders used the same motorcycle with on-board instrumentation to record the steering effort and the response of the machine. The tests were also videoed to gain extra information about rider behaviour. The results suggest that those riders that had been trained in exploiting countersteering were better able to avoid the obstacle and significantly better at returning the machine to the desired path thereby avoiding a potential secondary collision. It appeared that those riders who had learned by experience were still not proficient when faced with a sudden swerve to avoid scenario.

No description available.

Title: H-reflex, depending on the position of the joint Aim: The aim of this study is to determine whether the position of the ankle joint influences the parameters of the soleus muscle H-reflex. We are interested in a change of amplitude, latency and threshold of the H-reflex. Method: To measure H-reflex, we have used surface elektromygraphy. We examined two different positions of the foot in probands lying on the bed on their stomach. The first position was with the feet out of bed, around 90 degrees at the ankle joint (rest position). At the second position, the foot moved the bed and was in position in plantar flexion. Stimulation were performed over the tibial nerve in the popliteal fossa. The response, we recorded the surface electrode over the soleus muscle. Results: By changing the position of the ankle from rest to plantar flexion there was no statistically significant changes in amplitude, latency or threshold of the H-reflex. In plantar flection, we found a reduction of Hmax/Mmax ratio, which is probably due to reduced excitability alpha motoneurons through reciprocal ihibition from stretched muscle of the leg. Keywords: H-reflex, soleus muscle, joint position, surface EMG

Measured and calculated differential cross sections(DCS) are contrasted through the generalized ocsillator strength for impact energies of 16, 20, 40, 54.4, 60, 75, 100 and 200 eV. The recently constructed universal formula by Msezane and Sakmar is used to compare these results. Most of the results require renormalization and also show inaccuracy at small scattering angles. By also using the cubic spline function and the constructed formula from the universal formula, for the integral cross section by Chen and Msezane, total cross sections are calculated. These integral cross sections which serve as a good check to the measured and calculated DCS indicated the importance and need for the integral cross section formula for small scattering angles as contribution from this region ranges from to of the total contribution. The need for the universal extrapolation formula is thus found to be crucially important for accurate extrapolation.

Nesta pesquisa foram avaliados 30 pacientes, sendo 15 para cada gênero, idade iniciais entre 10,83 e 16,24 anos, sendo a média de idade inicial 13,32 anos; leucodermas, brasileiros, naturais da cidade de Bauru, caracterizados por má oclusão de Classe II 1ª e 2ª divisão de Angle, na presença ou não dos segundos molares superiores e sem comprometimento esquelético. Os jovens pertencentes a essa amostra receberam o aparelho Jones jig a fim de distalizar os molares superiores a uma relação molar de ?super Classe I?; sendo que em média esse dispositivo permaneceu por 0,86 anos, ou seja, 10 meses e 10 dias. Ao final da sobrecorreção, os molares distalizados receberam um botão de Nance e como ancoragem extrabucal, o AEB com tração média-alta (capacete jeans); com o intuito de verticalizar e corrigir a angulação radicular dos molares distalizados. Foram realizadas tomadas radiográficas em dois diferentes tempos; ou seja, telerradiografias em normal lateral inicial (T1) e pós-distalização (T2) a fim de avaliar as alterações dentárias e esqueléticas decorrentes do aparelho Jones jig. As medidas cefalométricas foram submetidas ao teste t dependente de Student para avaliar as alterações de T1 para T2 e o teste t independente para avaliar o dimorfismo entre os gêneros e os efeitos provocados pela presença dos segundos molares superiores. Com base nos resultados obtidos e a partir da metodologia empregada observou-se alterações dentárias significantes como movimentação distal linear e angular dos segundos e primeiros molares superiores, assim como intrusão no sentido vertical; sendo que a taxa de distalização mensal foi de 0,26mm. Também se confirmou efeitos indesejáveis como a perda de ancoragem refletida em mesialização, extrusão e angulação mesial dos segundos pré-molares, protrusão dos incisivos superiores, aumento do overbite e overjet. Pode-se confirmar que certas movimentações dentárias promovem significantes alterações esqueléticas de estruturas localizadas à distância, ou seja, observou-se extrusão significante dos segundos pré-molares superiores, o que resultou em rotação mandibular, aumento significante da altura facial ântero-inferior e protrusão do lábio inferior. Observou-se que a presença dos segundos molares superiores interfere significantemente apenas no resultado final da angulação distal dos primeiros molares superiores e que as maiorias das variáveis se correlacionam significantemente entre si. / Thirty patients were evaluated in this study, 15 males and 15 females, leukoderm, Brazilian, natural from Bauru city, with initial ages ranging from 10.83 years to 16.24 years, being the average age 13.32 years old. They were characterized by Angle Class II division I and II malocclusion, with or without the second maxillary molars, and, no skeletal compromising. The patients were treated with the appliance Jones jig. The treatment last for 0.86 years. It´s purpose was the distalization of the first maxillary molars to normal molar relationship. After this movement, the maxillary molars were anchored with Nance button, and extraoral headgear was used to correct tipping of the distalized molars. Lateral cephalograms were obtained at two observation stages: before treatment, and after distalization to evaluate dental and skeletal changes of appliance Jones jig. Cephalometric values were submitted to: dependent sample Student t test to identify changes between T1 and T2, and, independent sample Student t test to evaluate generic dimorphism and the effects from the presence of the second maxillary molars. On the basis of obtained results and applied methodology, significant dental changes were observed, such as distalization, distal tipping, and, intrusion of first maxillary molars, with the monthly rate of distal movement being 0.26mm. Anchorage loss was also observed, characterized by significant extrusion; mesial movement and tipping of the maxillary second premolar; protrusion of the maxillary incisors; and, increase of the overbite and overjet. It can be said that some dental movements promote significant skeletal changes, such as, significant extrusion of the second maxillary premolars resulted in clockwise mandibular rotation, increase of the lower anterior face height, and, protrusion of the lower lip. Another fact also observed was that the presence of second maxillary molars interfere significantly on the first maxillary molars?s distal tipping results, and, that the variables correlate significantly amongst themselves.

A estabilidade dos resultados obtidos pelo tratamento ortodôntico apresenta-se atualmente como um dos aspectos mais preocupantes e pouco compreendidos na literatura, sem respostas conclusivas. A sobremordida, ou trespasse vertical, define-se como o trespasse entre os incisivos superiores e inferiores, apresentando-se como um aspecto necessário para a correção das más oclusões e importante na avaliação dos resultados dos tratamentos e sua estabilidade. Este estudo se propôs a avaliar, cefalometricamente e em modelos de estudo, a recidiva da sobremordida e sua relação com as curvas de Spee e ocluso-incisal, e suas respectivas recidivas. A amostra (grupo experimental) constituiu-se das telerradiografias em norma lateral e modelos de estudo de 29 pacientes, de ambos os gêneros, que apresentavam inicialmente má oclusão de Classe II, 1 divisão e sobremordida profunda de no mínimo 3,5 mm, tratados com extração dos 4 primeiros pré-molares e aparelho ortodôntico fixo, utilizando-se a técnica Edgewise simplificada. Este grupo experimental foi comparado a um grupo controle, com oclusão normal, constituído também de 29 indivíduos. Ambos os grupos utilizados fazem parte do arquivo de documentação da Disciplina de Ortodontia da FOB-USP. Foram avaliadas, para o grupo experimental, as telerradiografias em norma lateral e os modelos de estudo do início, final e 5 anos pós-tratamento, e, para o grupo controle, as telerradiografias de dois tempos de avaliação, compatível com o tempo de tratamento do grupo experimental. Para a comparação intergrupos, utilizou-se o teste t não pareado, e para a comparação intragrupo, o teste ANOVA, e na presença de resultados significantes, aplicou-se também o teste de Tukey. Para verificar a relação da recidiva da sobremordida com as curvas de Spee e ocluso-incisal, utilizou-se o teste de correlação de Pearson. Pela análise dos resultados obtidos, observou-se que a sobremordida apresentou uma correlação significante com a curva de Spee na fase pós-contenção / The long-term stability of the treatment outcomes presents as one of the main points in orthodontic literature, without conclusive answers. The overbite is defined as the vertical distance between upper and lower incisors, and it is important for malocclusions correction and for evaluation of treatment and its stability. This study aimed to evaluate, in cephalograms and study casts, the overbite relapse and its relation with the curve of Spee. The sample (experimental group) comprised 29 patients of both genders, presenting Class II, division 1 malocclusion and an overbite of at least 3.5 mm, treated by Edgewise mechanics. This experimental group was compared to a control group of normal occlusion, comprising 29 subjects. Both groups are part of the records from Orthodontic Department at Bauru Dental School, University of São Paulo. For the experimental group, cephalograms and study casts of the pretreatment, posttreatment and 5 years postretention were studied, and for the control group, cephalograms in two times of evaluation, compatible with the treatment time of the experimental group. The independent t test was used for the intergroup comparison, and the one way ANOVA, for intragroup comparison. In order to verify the relation between the overbite relapse and the curve of Spee, a Pearson's correlation test was performed. The results showed that the overbite was significantly corrected by the orthodontic treatment, when compared to the control group, and presented a significant relapse in the postretention phase. The overbite relapse presents a significant correlation with the curve of Spee in the postretention stage