In Experiments 1 to 8 an attempt was made to examine the nature of the displacements found in the traditional line bisection test when applied to normal (right-handed), as well as brain lesioned subjects. The problem with this test is that it invariably confounds perceptual and motor components which might both contribute to the observed errors. However, use of the 'landmark task' enables an examination of perceptual effects in isolation. It was found that five out of six neglect patients judged the left half-line of a centrally bisected line as shorter than the right half-line. Moreover, it was consistently shown that cueing strongly influenced judgements in normal and left and right hemisphere lesioned subjects (without neglect) in that it caused them to overestimate the cued part of the line. It was argued that the perception of relative size is subject to systematic distortion as a function of this selective attention within the visual field. Neglect patients may present an abnormal example of this attentionally- induced illusion in that their attentional resources may be abnormally biased towards the ipsilesional space. The result of this imbalance may be to cause, quite directly, a gross abnormality of size perception. Nonetheless one of the neglect patients did not show spatial misperception but spatially misdirected actions, in line with what has been described as directional hypokinesia. Experiments 9 to 12 were designed to demonstrate any possible contribution the right hemisphere might make to visuomotor control, but the data on normal subjects gave little indication of a specific right hemisphere involvement in such tasks. Neither use of a spatial bisection task, nor absence of visual feedback of the moving hand or arm seemed to produce left hand advantages on the dependent measures. On the other hand, RCVA patients proved to be impaired in their reaching behaviour in that they erred systematically to the right of the true target over all three spatial positions, in the absence of visual feedback. The bias was interpreted as a pure example of directional hypokinesia.

Experiments were conducted to examine the differential capabilities of the cerebral hemispheres for the visual perception of motion. Subjects were normal right handed adult male and female humans. Stimuli were viewed binocularly and responses were manual in all studies. Lateralized low contrast real motion was presented using random texture patterns. The task was to correctly detect the direction of motion. The outcome was a significant hemisphere x trials interaction. The right hemisphere improved significantly over trials while the left hemisphere did not. Using random texture patterns in which a small lateralized square was presented in apparent motion, hemispheric superiorities were found to depend on fairly basic stimulus parameters. For low contrast relatively long stimulus field durations, the right hemisphere was significantly superior. For higher contrast apparent motion stimuli with a "masking" ISI, the left hemisphere was significantly better at accurately detecting the direction of motion. V shaped stimuli may be presented in apparent motion so as to be seen as either moving within the stimulus plane, or rotating in depth outside it. The percentage of "space" (i.e., rotation) responses increases as the ISI is lengthened. The hemispheres did not differ significantly in their judgments of motion in depth, therefore, they appear to be employing identically calibrated detection mechanisms. However, female right hemisphere "space" responses remained constant over trials, while analogous male responses decreased linearly. Stimulus parameters which had been shown in earlier experiments to result in hemispheric differences were avoided, and subjects required to identify apparently moving shapes in a random texture background. No hemispheric differences were observed in this detection task. An additional finding was that female subjects tend to more frequently report that sub-vocal verbalization mediated their (manual) responses.

The preparation and initiation of movement has previously been described using a neural accumulation model; this model involves an increase of neural activation in the motor cortex (M1) from baseline to a subthreshold level following a warning signal, which is maintained until presentation of an imperative stimulus (IS). Activity then increases until reaching movement initiation threshold. This model predicts that variability in activation during preparation may influence reaction time (RT) and its variability. The purpose of this thesis project was to determine whether differences in RT/variability of RT during the completion of tasks with varying levels of complexity may be attributable to differences in neural excitability in M1. To test this prediction, transcranial magnetic stimulation (TMS) delivered concurrently with an IS was used to determine neural excitability for movements with different accuracy demands. It was hypothesized that higher accuracy demands would result in lowered amplitude and/or greater variability of neural activation, and consequently slower/more variable RT. Fifteen healthy participants completed a simple RT task involving a targeted wrist extension movement under three different accuracy conditions (easy, moderate, difficult). TMS was delivered concurrently with the IS on 50% of trials during each condition. While pilot testing showed RT differences between accuracy conditions (Appendix A), the data presented here failed to detect significant differences in RT latency (F(2, 28) = .074, p = .929) or variability (F(1.432, 20.053) = .633, p = .538) between conditions . Similarly, no difference in MEP amplitude was observed between difficulty conditions (F(2, 28) = 2.439, p = .106). However, a subset of participants (n = 7) did show significant RT increases between easy and hard conditions (t(6) = 2.531, p = .045), but this subset still failed to show differences in MEP amplitude (t(6) = 1.157, p = .291) or variability (t(6) = 1.545, p = .173), suggesting that preparatory levels at the IS may be similar for movements involving both high and low accuracy demands.

This thesis examines the policies of the socialist movement in the last two decades of the nineteenth century with regard to the education of children. This study is used to both reassess the nature of these education policies and to criticise the validity of the historiographical models of the movement employed by others. This study is thematic and examines the whole socialist movement of the period, rather than a party or an individual and as such draws out the common policies and positions shared across the movement. The most central of these was a belief that progress in what was called the 'moral' and the 'material' must occur simultaneously. Neither the ethical transformation of individuals, nor, the material reformation of society alone would give real progress. Children, for example, needed to be fed as well as educated if the socialist belief in the power of education and the innate goodness of humanity was to be realised. This belief in the unity of moral and material reform effected all socialist policies studied here, such as those towards the family, teachers, and the content of the curriculum. The socialist programme was also heavily centred on the direct democratic control of the education system, the ideal type of which actually existed in this period in the form of school boards. The socialist programme was thus not a utopian wish list but rather was capable of realisation through the forms of the state education machinery that were present in the period. It is argued in this thesis that the removal of this democratic machinery in 1902 crucially de-stabilised this unity of the ethical and the material and was one of the factors that led to the growth of state-centred and bureaucratic socialist solutions.

Resumo: O objetivo dessa tese foi avaliar os efeitos da intrusão ortodôntica no processo de reparação de lesão de furca grau III em cães, e da presença de fator de necrose tumoral alfa (TNFα) e/ou interleucina-1 beta (IL-1ß) na mecanoresposta de células com característica de osteócitos e osteoblastos in vitro. No estudo in vivo, lesões de furca grau III foram criadas em pré-molares inferiores de sete cães. Após 75 dias, as lesões foram aleatoriamente tratadas com cirurgia a retalho (OFD) associada ou não à regeneração tecidual guiada (GTR) e enxerto ósseo autógeno (BA). Após um mês, iniciou-se a intrusão ortodôntica (I) em parte dos dentes tratados pelas duas diferentes abordagens (grupos teste), por meio de ancoragem em miniimplantes. Os cães foram sacrificados após três meses de movimentação e um mês de contenção. Todas as lesões de furca grau III foram reduzidas para grau II ou I nos grupos teste. O mesmo foi observado em 50% das lesões nos grupos controle (sem movimentação). O nível de inserção clínico foi reduzido nos grupos teste, no final da contenção (p<0.01). O grupo OFD+I apresentou maior preenchimento ósseo que os demais grupos (p<0.05), demonstrando superioridade desta associação, no tratamento de lesões de furca grau III, em cães. Esses resultados levantaram a hipótese de que o processo de degradação da membrana e/ou enxerto ósseo interagiria negativamente sobre o processo de reparo quando associado a forças ortodônticas, pois a presença de mediadores inflamatórios estaria intensificada. É conhecido que a alteração tecidual proveniente da movimentação ortodôntica é resultado da ação de mediadores químicos sobre as células dos tecidos periodontais. Portanto, buscamos avaliar in vitro a ação de duas citocinas pró-inflamatórias, TNFα e IL-1ß, sobre células ósseas em presença e ausência de carga mecânica. / Abstract: The aim was to assess the effects of orthodontic intrusion on the healing of class III furcation lesions in dogs, and of the presence of tumor necrosis factor alpha (TNFα) and/or interleukin-1 beta (IL-1ß) on the mechanoresponse of osteocyte and osteoblast-like cells in vitro. In the in vivo study, class III furcation lesions were created in lower pre-molars of seven mongrel dogs. After 75 days, teeth were randomly treated with open flap debridment (OFD) associated or not to guided tissue regeneration (GTR) and bone autograft (BA). After one month, teeth were randomly assigned to orthodontic intrusion using mini-implants anchorage or no movement. Dogs were sacrificed after three months of movement and one month contention. All class III furcations were closed or reduced to class II or I lesions in the intrusion groups while 50% of the class III lesions in non-moved teeth remained unchanged. Clinical attachment level was reduced in the intrusion groups by the end of contention (p<0.01). OFD + I presented smaller soft tissues area and larger bone tissue area than other groups (p<0.05). Orthodontic intrusion with mini-implants anchorage improved healing of class III furcation defects after OFD in dogs. Based on these results we hypothesized that degradation of membrane and/or bone autograft can negatively interfere on repair when associated to orthodontic movement because inflammatory mediators are intensified. It's known that cytokines are present during orthodontic movement which are acting on periodontal cells. Therefore we evaluated in vitro the effects of two pro-inflammatory cytokines, TNFα and IL-1ß, on bone cells in presence or absence of mechanical loading. / Orientador: Joni Augusto Cirelli / Coorientador: Rosemary Adriana Chiérici Marcantonio / Banca: Ana Cláudia Moreira Melo / Banca: Enilson Antonio Sallum / Banca: Ary dos Santos Pinto / Banca: Silvana Regina Perez Orrico / Doutor

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Christian disunity, as has been shown by Rouse and Neill, has been a major problem in the Church from the time of its inception. In Apostolic times Paul had to face serious dissension at Corinth and elsewhere. The great councils of the 4th and 5th centuries were convened to settle doctrinal disputes. The schism between Eastern and Western Christianity, which finally became permanent at about the end of the 12th century, was the result of thoroughgoing doctrinal as well as cultural differences. At the Reformation, Christianity was again drastically divided and between the 16th and 19th centuries,divisions were greatly multiplied. Chap. 1, p. 1.

The purpose of the study was to establish a new place order in the transport grain for taxis through a design that will suit the urban context. It attempts to render taxis and their associated facilities preferable and acceptable for the city user and bystander. The relationship between time and movement was studied to generate a design concept that depicts the path of the user as an experience of comfort and convenience. A quantitative and qualitative method was applied. The study examined current taxi ranks through case studies, site visits, interviews and discussions. This information was interpreted within an urban scope. The process of elimination defined the urban taxi facility. Certain requirements gained prominence to achieve the aim of a sustainable multi-functional facility with the user as primary focus. The main conclusion was that architects have a responsibility towards the environment, and should design spaces that display a relationship between human and nature thereby creating a new typology for taxi facilities. / Dissertation (MArch(Prof))--University of Pretoria, 2010. / Architecture / unrestricted

This thesis is concerned with the modelling of sea ice, particularly in regions where it is composed of individual floes interacting through collisions. This has been done by modifying and extending existing models that have demonstrated their ability to simulate sea ice in various Arctic and Antarctic regions. The purpose of this study is the introduction of the representation of floes, in terms of their size and number, into a sea ice model, thus adding a feedback mechanism and a further output to the output fields normally produced by sea ice models, the ice velocity and the ice thickness distribution and the ice concen tration. Many of the physical processes concerning floes that are relevant to a sea ice model have not yet been investigated quantitatively. These aspects of floe behaviour used as model input are calculated from idealized mechanical models of a floe field. These include determinations of floe collision rates, side melting of floes and the cracking of floes in high winds. The strength of the pack ice is investigated, and in particular the effect of open water on the strength is considered. The shape of a plastic yield curve used in the model to determine the ice interaction forces is derived theoretically. The model used includes both thermodynamics and dynamics. The ice thickness characteristics and floe sizes change due to growing and melting, advection, floe cracking, floe collisions, and redistribution processes such as ridging and rafting. Daily wind and temperature data together with long term ocean currents are used as input to drive the model. The results of a six month simulation of the sea ice development in the (Eas t) Greenland region are presented and discussed together with a comparison with the observations.