New developments in information and communications technologies have rapidly made their way into the forefront of educational concerns. With exciting possibilities for global communication, access to vast amounts of information and new approaches to teaching and learning practices, a small number of schools have integrated the technology into the school environment. However, the majority of schools are just feeling their way and this is particularly so in small rural schools which are removed from the high technology communications networks of the capital cities. This study placed open learning technology into three rural schools where the teachers had control over its use. Using qualitative multi-site case study techniques, the effect of the technology on the planning and teaching strategies of the teachers, classroom organisation and management, changes in teacher-student interactions, student motivation, curriculum enhancement and/or extension, the role of the teacher, and professional development issues was investigated. It was found that the use of the technology had a positive effect on encouraging open learning and student-centred approaches to lesson delivery. The Internet and e-mail were accepted by the teachers and the wider school community and became part of normal classroom activities. Staff development opportunities figured largely in the outcomes of this study being revealed as a necessity for teacher adoption of the innovation. The leadership role of the principals emerged as an important theoretical construct influencing the implementation of the innovation. Finally, the introduction of the technology was found to contribute to breaking down the barriers of distance that are a characteristic of rural and isolated schools. By providing teachers in rural schools with access to open learning technology that can be readily integrated into teaching activities, it is likely that lasting change in attitude to the legitimacy of information gained through the technology, and a greater level of independent student classroom activity, will occur.

Made available in DSpace on 2014-12-17T14:20:14Z (GMT). No. of bitstreams: 1 EdvaniaDC_1_52.pdf: 3112703 bytes, checksum: bfda1659150981847294f382e8fc1261 (MD5) Previous issue date: 2009-08-28 / It investigates the perception of the public space in the city of Natal. It approaches, therefore apprehension forms, entails and experiences, in the formalization in the way of seeing, to live and to interact with that part of the urban territoriality. With that perspective, they were focalized, especially, three periods lived in Natal: the first two decades of the century XX, the beginning of the forties, also of the previous century, and the scenery with which that city comes at the present time. With that direction, it puts back in focus, and for reflection, not just an universe that makes possible the people to interact, independent of the individual will of each one, but also the importance of that interaction for the social and political life of the city and for the formation of a wider and interactive vision of the people with yours surroundings / Investiga a percep??o do espa?o p?blico na cidade de Natal. Aborda, portanto formas de apreens?o, v?nculos e experi?ncias, na formaliza??o no modo de ver, vivenciar e interagir com essa parte da territorialidade urbana. Com essa perspectiva, foram focalizados, em especial, tr?s per?odos vivenciados por a capital potiguar: as duas primeiras d?cadas do s?culo XX, o in?cio dos anos quarenta, tamb?m do s?culo anterior, e o cen?rio com o qual essa cidade se apresenta na atualidade. Com esse direcionamento, recoloca em foco, e para reflex?o, n?o apenas um universo que possibilita as pessoas interagirem, independentes da vontade individual de cada um, mas tamb?m a import?ncia dessa intera??o para a vida social e pol?tica da cidade e para a forma??o de uma vis?o mais ampla e interativa das pessoas com seu entorno

In the normal operation of quadrupole ion trap mass spectrometers, the trapped ions are ejected symmetrically through both the upper (detector) and lower(source) endcap electrodes during mass selective boundary ejection experiment. This reduces the sensitivity of the instrument by almost 50%. In this preliminary study, we altered the geometry parameters of the quadrupole ion traps to introduce asymmetry. The asymmetry displaced the ion cloud towards the detector endcap which resulted in a preferential ejection through this endcap, thus imparting directionality to the ejected ions and hence to the sensitivity enhancement. Two symmetrical mass analyzers have been taken up for numerical study. They include the Paul trap(QIT) and the cylindricaliontrap(CIT). Asymmetry to these geometries is introduced in two ways, one by varying the upper endcap hole radius alone and in other by stretching the trap along the upper endcap only. The escape velocity plots and mass selective boundary ejection simulations are used to demonstrate the directionality of ion ejection for these geometries. The simulations revealed a significant increase in the number of ions getting ejected in the direction of asymmetry.

Ion traps used in mass spectrometers are of two classes. One class consists of traps having three electrode geometries which have rotational symmetry about central axis. They are called axially symmetric ion traps. Paul trap, Cylindrical Ion Trap(CIT) are examples in this class. Other class of traps contain 2D electric field inside them which has same profile along the central axis due to translational symmetry. Linear Ion Trap(LIT) and Rectilinear Ion Trap(RIT) are examples in this class. In the ideal hyperbolic geometries of Paul trap and LIT, electric field is a perfectly linear function of distance from the center of the trap. But when these ideal geometries are simplified in to simpler geometries of the CIT and the RIT for ease in machining, linearity of field, which is a specialty of Paul trap and LIT is lost. In this thesis, an effort is made to optimize the field within the traps by using split electrodes. The ring electrode of the CIT and both pairs of electrodes in the RIT are divided into more number of parts. Suitable voltages are applied on these parts to improve the linearity of the field. This thesis contains six chapters. Chapter 1 contains a background information about mass spectrometry. Chapter 2 discusses the Boundary Element Method (BEM) used to calculate charge distribution and Nelder-Mead method used for optimization. It also shows the calculation of multipoles. In Chapter 3, two new geometries namely split-electrode RIT and split-electrode CIT are considered with the objective of improving the linearity of electric field inside them. It is shown here that by applying certain external potential on various parts of split electrodes of these geometries, it is possible to improve the linearity of electric field inside them. In Chapter 4, capacitor models of new geometries proposed in chapter 3 are discussed. The use of external capacitors as a replacement to external power supply is also discussed in this chapter. InChapter5, study similar to that ofChapter3is carried out by splitting the geometries in more number of parts. The possibility of improved field profile is investigated by applying full potential to some of these parts and keeping other parts at ground potential. In Chapter 6, concluding remarks are discussed.

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The problem of low domestic savings is inherent in most Southern African Development Community (SADC) countries. This has motivated most of the SADC countries to institute policies that seek to attract foreign capital to cover the investment deficit that arises from low domestic savings rates. This study gives robust conclusions on the effectiveness of individual tax incentives commonly used by SADC countries in attracting foreign mobile capital. This study has broadened the dimensions research can take in analysing the contribution of tax incentives to Foreign Direct Investment (FDI) inflows into developing countries. In separating individual tax incentives mainly used in the SADC region the study gives a robust analysis on the impact of each tax incentive on FDI inflows into SADC countries. The tax incentives used in this study are: tax holidays, corporate income tax (CIT), reduced CIT in specific sectors and losses carried forward. The study also derives data indices for governance, infrastructure and economic policy variables which gives the study clean and reliable data for efficient regression results. These macroeconomic data derivations assist in giving the FDI attraction analysis more variables and well behaved data in drawing conclusions. Through an analysis and comparison of trends in FDI inflows and stock data in different African regions the study draws important conclusions on the impact of the socio-economic environment in FDI attraction. The study, in consultation with data from the period 2004 to 2013 separates the SADC countries into four panels based on resource richness. Panel 1 includes the resources-rich countries, Panel 2 the resources-poor countries, Panel 3 all SADC countries, except South Africa and Panel 4 all the SADC countries. Each of the estimate models in this study, use individual tax incentives variables to avoid the effects of collinearity between different tax incentives variables and to improve the predictive power of the panel data models. This study derived tax incentives data for individual SADC countries, from Ernst and Young’s worldwide tax data. Regular tax incentives in the SADC are derived from tax holidays, corporate income tax (CIT); losses carried forward and reduced CIT in specific sectors. This study seeks to achieve two major objectives: firstly, to establish the effectiveness of tax incentives in attracting FDI inflows into SADC countries, and, secondly, to establish other variables that influence FDI inflows into SADC countries. The study estimated four panels for SADC countries, separated according to resource richness. This was done because different types of FDI are dependent on the available resources in developing countries and thus factors that influence the FDI inflows differ according to resource richness. Resource-seeking FDI moves to resources-rich economies, market-seeking FDI goes to economies that have access to larger markets and efficiency-seeking and strategic-asset-seeking FDI move to economies that ensure efficient use of their capital resources. Thus, as expected, factors that attract FDI to countries in the separate panels differ in direction of causality and magnitude of impact. The study adopts a system Generalised Method of Moments (SYS GMM) methodology to address the problem of endogeneity associated with dynamic panel data models. The estimated results established that tax holidays positively explain FDI inflows in Panel 2. CIT was found to negatively affect FDI inflows into all SADC countries despite their particular category of resource-richness. Losses carried forward are insignificant in all panels and reduced CIT in specific sectors negatively influences FDI inflows in Panel 1 and surprisingly positively influences FDI inflows in Panel 2. The lagged FDI variable shows a positive relationship with current year FDI inflows. The governance index is significant and positively affects FDI inflows in panels 1, 3 and 4. Panel 2 shows a negative relationship between governance and FDI inflows. Market potential measured by GDP growth rate is insignificantly different from zero in all the four panels in the study and negatively signed, except in models A and C of Panel 2. The stock of infrastructure is significant and negatively signed in all the panels. The log natural resources variable though insignificant in some models, mainly, exhibit a significant and negative effect in most models of the study’s panel estimations. The trade openness variable is positively related to FDI inflows in Panel 1. Panel 2 show negative effects of trade openness to FDI inflows. Financial globalisation significantly impacts positive FDI inflows in all the four panels. The economic policy variable is insignificant in all the four panels of the study, except, in model B of Panel 1 where it is weakly significant at 10% level and negatively signed. The study concludes that tax incentives are important in FDI attraction in the SADC countries; therefore, an effective tax mix that ensures efficient use of tax incentives is important to ensure sustainable FDI inflows into the region. Good governance is important in the region for FDI inflows to increase. Increasing government rents from natural resources reduces FDI inflows in the SADC. Previous year flows of FDI are positively related to current year inflows, thus consistent FDI attraction policies in the SADC are important. Infrastructure in the SADC should be consistently improved to ensure suitability with the dynamic nature of foreign investment. Financial markets should be developed to ensure effective flow of capital and growth in economies through more investment. / Economics / D. Com.. (Economics)

Le rôle que pourrait jouer l’interaction des systèmes cholinergiques (ACh) et dopaminergiques (DA) semble crucial dans la physiopathologie de certaines maladies neurodégénératives, en particulier dans la démence à corps de Lewy (DCL). Ce travail de thèse se propose de valider un protocole d’imagerie moléculaire en tomographie d’émission monophotonique, consistant en un marquage de l’ACh et de la DA chez un même individu, afin de pouvoir étudier in vivo les interactions ACh/DA.Après avoir mis au point chez des sujets âgés et des patients atteints de maladie d’Alzheimer une méthode d’imagerie cérébrale quantitative des neurones ACh utilisant un radioligand sélectif du transporteur vésiculaire de l’ACh, le [123I]-IBVM, et basée sur une modélisation pharmacocinétique, nous avons montré le potentiel de cette méthode à mettre en évidence une atteinte différentielle des circuits ACh dans la Paralysie Supranucléaire Progressive et l’Atrophie Multisystématisée. Dans la dernière partie de ce travail de thèse, nous avons pour la première fois réalisé un double marquage des systèmes ACh et DA dans la DCL, en utilisant, en plus du [123I]-IBVM, un radioligand sélectif du transporteur de la dopamine et validé en routine clinique, le [123I]-FP-CIT. En parallèle, une étude comportementale évaluant la présence d’hallucinations, de fluctuations cognitives, d’altérations des rythmes circadiens ainsi qu’un bilan des performances neuropsychologiques, ont été menés. Cette étude est actuellement en cours de réalisation. Les tous premiers résultats montrent l’existence de liens cohérents entre les données d’imagerie moléculaire et les données cliniques. / The question of how acetylcholine (ACh) and dopamine (DA) could be involved together in the pathophysiology of some neurodegenerative disorders is essential, particularly in dementia with Lewy bodies (DLB). The present study aims at assessing an in vivo molecular imaging method of both ACh and DA brain systems using single photon emission computed tomography. In the first part of the present study, a method based on pharmacokinetic analysis making it possible to quantify ACh neurons in vivo, using [123I]-IBVM, a specific radioligand of vesicular acetylcholine transporter, was developed and validated in healthy subjects and Alzheimer’s disease patients. Then, we showed the ability of our method to demonstrate a differential alteration of ACh pathways in Progressive Supranuclear Palsy and Multiple System Atrophy patients. In the last part of this study, we imaged for the first time both ACh and DA systems in DLB patients, using not only [123I]-IBVM, but also [123I]-FP-CIT, a specific radioligand of dopamine transporter. Concomitantly, a behavioral exploration of hallucinations, fluctuating cognition and disturbances of circadian rhythms was achieved in these patients, as well as a neuropsychological examination. This study is currently in progress. The first results show consistent links between imaging and clinical data.

This study uses aspects of time series methodology to model and forecast major taxes such as Personal Income Tax (PIT), Corporate Income Tax (CIT), Value Added Tax (VAT) and Total Tax Revenue(TTAXR) in the South African Revenue Service (SARS). The monthly data used for modeling tax revenues of the major taxes was drawn from January 1995 to March 2010 (in sample data) for PIT, VAT and TTAXR. Due to higher volatility and emerging negative values, the CIT monthly data was converted to quarterly data from the rst quarter of 1995 to the rst quarter of 2010. The competing ARIMA/SARIMA and Holt-Winters models were derived, and the resulting model of this study was used to forecast PIT, CIT, VAT and TTAXR for SARS fiscal years 2010/11, 2011/12 and 2012/13. The results show that both the SARIMA and Holt-Winters models perform well in modeling and forecasting PIT and VAT, however the Holt-Winters model outperformed the SARIMA model in modeling and forecasting the more volatile CIT and TTAXR. It is recommended that these methods are used in forecasting future payments, as they are precise about forecasting tax revenues, with minimal errors and fewer model revisions being necessary. / Statistics / M.Sc. (Statistics)

Les centres d’information sur les tératogènes (CIT) fournissent aux professionnels de la santé ainsi qu’au public de l’information sur les risques et bienfaits associés à l’utilisation des médicaments durant la grossesse et l’allaitement. Le Centre IMAGe (Info-Médicaments en Allaitement et Grossesse) du CHU Sainte-Justine (Centre Hospitalier Universitaire Sainte-Justine) au Québec, est un CIT qui offre depuis 1997 un service téléphonique d’information gratuit aux professionnels de la santé. Deux études ont été réalisées à partir des appels reçus au Centre IMAGe. La première étude a été réalisée sur l’ensemble des appels reçus entre janvier 2004 et avril 2007 au sujet de femmes qui prenaient ou envisageaient prendre un médicament durant la grossesse ou l’allaitement. Les objectifs de cette étude visaient à déterminer les classes de médicaments les plus fréquentes ainsi que les indications d’utilisation et les déterminants d’un appel à leur sujet (caractéristiques maternelles associées). Les antidépresseurs, les anti-inflammatoires, les antibiotiques, les benzodiazépines et les antipsychotiques sont les classes de médicaments qui correspondaient aux plus grands nombres d’appels. Cela porte à croire que pour ces classes de médicaments, il existe chez les professionnels de la santé un besoin d’information en ce qui concerne les risques et bienfaits de leur utilisation durant la grossesse et l’allaitement. La dépression représentait une des trois indications les plus prévalentes chez les femmes qui prenaient ou désiraient prendre des antidépresseurs, des benzodiazépines ou des anti-psychotiques durant la grossesse ou l’allaitement. Le tabagisme était associé à l’utilisation des antidépresseurs et des anti-psychotiques durant la grossesse, ainsi qu’à un appel au sujet des anti-inflammatoires durant l’allaitement. La deuxième étude a été réalisée sur l’ensemble des appels reçus entre janvier 2003 et mars 2008. Cette étude visait à déterminer l’impact des avis émis par Santé Canada concernant les risques de l’exposition aux antidépresseurs durant la grossesse et celui concernant le retrait du rofécoxib, sur le nombre d’appels reçus à IMAGe. L’analyse des séries temporelles du nombre hebdomadaire d’appels reçus a révélé que l’avis de Santé Canada sur les risques de malformations cardiaques associés à l’utilisation de la paroxétine lors du premier trimestre de la grossesse a généré une augmentation statistiquement significative, soudaine et permanente du nombre d’appels reçus à IMAGe au sujet des antidépresseurs. Ces études permettent de mieux comprendre le besoin d’information des professionnels de la santé sur les risques et bienfaits de l’utilisation des médicaments durant la grossesse et l’allaitement. / Teratogen Information Services (TIS) are giving information on the risks and benefits associated with medication use during pregnancy and lactation, to the health care providers and the public. IMAGe Center at the CHU Sainte-Justine in Quebec is a TIS which providing since 1997 a free telephone information service to the health care providers. Two studies were conducted using the calls received at IMAGe Center. The first study included all the calls received between January 2004, and April 2007, concerning women who used or expected to use medication during pregnancy or lactation. The objectives of this study aimed to identify the most frequent medication classes, the indications of use, and the predictors of a call concerning them (associated maternal characteristics). Antidepressants, anti-inflammatory drugs, antibiotics, benzodiazepines, and anti-psychotics represented the medication classes with the greater amount of calls. These results rise to the possibility that more information about the risks and benefits associated with the use of these medication classes during pregnancy and lactation is needed by the health care providers. Depression was in the top three of the most prevalent indications of use for the antidepressants, benzodiazepines, and anti-psychotics. Smoking was associated with the use of antidepressants and anti-psychotics during pregnancy, and with a call concerning the anti-inflammatory drugs during lactation. The second study included all the calls received between January 2003, and March 2008. This study aimed to identify the impact of the Health Canada (HC) warnings, concerning the risks of antidepressant use during pregnancy, and related to the rofecoxib market withdrawal, on the number of calls received to IMAGe. Time series of the weekly number of calls received demonstrated that the Health Canada warning on the risk of cardiac malformations associated with paroxetine use during the first trimester of pregnancy generated a statistically significant abrupt and permanent increase of the calls received at IMAGe about the antidepressants. These studies ensure to better understand the information need of the health care providers concerning the risks and benefits of medication use during pregnancy and lactation.

The thesis aims at building an experimental setup for conducting the boundary ejection and resonance ejection experiments on wide variety of ion trap mass analyzers. The experimental setup has two parts namely power electronics circuits and mechanical assembly. The focus of the thesis is on the electronics hardware which provides various power sources required for the operation of ion trap mass spectrometer. The electronics circuits discussed in the thesis have better performance, flexibility and ruggedness compared to the existing setup. The traditional power supplies used in ion trap mass spectrometers are all linear supplies. But one major drawback of these supplies is the high power dissipation and consequently, the power efficiency degrades. We are trying to introduce switch mode power supplies to reduce the power dissipation loss and eventually increase the power efficiency. In the course of the work the following power supplies have been developed. The supplies are - 1.Constant current source, 2.Filament base, 3.gating power supply and pulsing circuit, 4.High voltage DC power supply and 5. High voltage RF generator.