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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.
261

Physical activity levels among people living with HIV/AIDS treated with high active antiretroviral therapy in Rwanda

Augustin, Murenzi January 2011 (has links)
The current study aims to determine physical activity levels among people living with HIV treated with high active antiretroviral therapy in Kigali, Rwanda. A cross-sectional design using quantitative method was used. The participant’s levels of physical activity participation and their association with anthropometric profiles were measured, using a structured selfadministered questionnaire adapted from the Sub-Saharan Africa Activity Questionnaire. Based on a scientific calculation, 407 clients passing through the clinics were included in the study. A convenient sample of people attending the clinics approached to participate voluntarily in the study. The findings of the current study highlighted the lack of motivation, lack of time and fear of worsening the disease amongst the strong barriers to physical activity participation. The current study recommends education about the benefits of physical activity participation and encouragement of patient treated with high active antiretroviral therapy in Rwanda to be emphasized on to improve their lives.
262

SMILETRAP I / II : Precision Improvements in Penning-Trap Mass-Spectrometry

Suhonen Linné, Markus January 2009 (has links)
This thesis describes the final precision mass measurements with SMILETRAP I, where a relative precision of < 1 ppb (10-9) was reached routinely, and the development of SMILETRAP II, aiming for measurements with < 0.1 ppb relative precision. The emphasis of the thesis is on the implementation of new techniques for achieving this precision improvement with SMILETRAP II. The Ramsey multiple-pulse excitation technique was tested at SMILETRAP I, and a reduction of the statistical uncertainty by factor three could by verified. The technique was applied in the last measurement with SMILETRAP I on H2+ and D+ ions. From these measurements the proton mass was deduced with a relative error of 0.18 ppb. It was found that temperature dependent magnetic field oscillations limited us from reducing the uncertainties further. A technical achievement of reducing the peak to peak temperature oscillation in the trapping region of SMILETRAP II by a factor four is presented, which should give an extended observation time and likewise improved precision. The new SMILETRAP II super-conducting magnet, with a slightly stronger field of 5.8 T compared with the previous of 4.7 T, was installed and adjusted.  A careful field alignment and reduction of inhomogeneities was done for minimizing the disturbances of the cyclotron frequency for improved precision. In that attempt, the localization and control of the trapped ion motion is also important. Thus a new cooling trap was set up. In the spring of 2009 coherent axial motion of a confined ion cloud was discovered in the cooling trap. By observation of the axial oscillations we can see the effects of evaporative cooling in the reduction of the axial energy distribution. Storing the ions up to 1 s in the cooling trap reduces the energy distribution by a factor of five. Other remarkable results of the ion oscillations are also reported. / At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 1: In progress. Paper 3: Submitted.
263

Ajouter de l'information spatiale aux modèles de composant logiciel - l'effet de localisation

HASSAN, Ali 25 September 2012 (has links) (PDF)
Highly distributed environments (HDEs) are deployment environments that include powerful and robust machines in addition to resource-constrained and mobile devices such as laptops, personal digital assistants (or PDAs), smart-phones, GPS devices, sensors, etc. Developing software for HDEs is fundamentally different from the software development for central systems and stable distributed systems. This argument is discussed deeply and in-details throughout this dissertation. HDE applications are challenged by two problems: unreliable networks, and heterogeneity of hardware and software. Both challenges need careful handling, where the system must continue functioning and delivering the expected QoS. This dissertation is a direct response to the mentioned challenges of HDEs. The contribution of this dissertation is the cloud component model and its related formal language and tools. This is the general title. However, and to make this contribution clear, we prefer to present it in the following detailed form: (1) We propose a paradigm shift from distribution transparency to localization acknowledgment being the first class concern. (2) To achieve the above mentioned objective, we propose a novel component model called cloud component (CC). (3) In this dissertation we propose a new approach to assemble CCs using systematic methodology that maintains the properties of CC model. (4) Cloud component development process and cloud component based systems development process. (5) Location modeling and advanced localization for HDEs are the pivotal key in our contribution. (6) Formal language to model single CC, CC assembly, CC development process, and CC based systems. (7) We finally present our fully-developed supporting tools: the cloud component management system CCMS, and the Registry utility. To respond to the challenges posed by HDEs, and to maintain expected software quality at the user endpoint, we think we need to pass a ¿paradigm shift¿ from the way software is designed and implemented currently to our new vision that this dissertation is devoted to. This is a paradigm shift from distribution transparency to localization acknowledgment being the first class concern. The contribution in this thesis has several faces as explained above, but still, these faces are cohesive. Each of these faces form a partial contribution, however, this partial contribution does not mean anything if isolated from the overall proposal. Moreover, the merit of the overall proposal can not be grasped by reading one partial contribution. The merit of the proposal is evident only if all parts of this work are cohesively organized. Finally, we claim that our proposal spans the entire software development process for HDEs, from requirements to deployment and runtime management.
264

The TITAN electron beam ion trap: assembly, characterization, and first tests

Froese, Michael Wayne 19 September 2006 (has links)
The precision of mass measurements in a Penning trap is directly proportional to an ion's charge state and can be increased by using highly charged ions (HCI) from an Electron Beam Ion Trap (EBIT). By bombarding the injected and trapped singly charged ions with an intense electron beam, the charge state of the ions is rapidly increased. To use this method for short-lived isotopes, very high electron beam current densities are required of the TITAN EBIT, built and commissioned at the Max-Planck-Institute for Nuclear Physics in Heidelberg, Germany and transported to TRIUMF for the TITAN on-line facility. This EBIT has produced charge states as high as Kr34+ and Ba54+ with electron beams of up to 500 mA and 27 keV. Once the EBIT is operational at full capacity (5 A, 60 keV), most species can be bred into a He-like configuration within tens of ms. / October 2006
265

Transport hochgeladener Ionen durch Nanokapillarfolien und makroskopische Glaskapillaren

Kreller, Martin 04 July 2013 (has links) (PDF)
In dieser Arbeit wird die Transmission von hochgeladenen Ionen durch Nanokapillarfolien und makroskopische Glaskapillaren untersucht. Die systematische Analyse des übertragenen Ionenstrahls liefert Informationen zur Physik der Ionentransmission und hier insbesondere zum Einfluss des Anstellwinkels zwischen Kapillarachse und Richtung des einfallenden Ionenstrahls und zum Einfluss der kinetischen Energie des einfallenden Ionenstrahls auf den Transmissionsprozess. Es werden Ionenoptiken aus Nanokapillarfolien und makroskopischen Glaskapillaren konstruiert und deren Eigenschaften zur Ionenstrahlformierung untersucht. Der durch das Kapillartarget transportierte Ionenstrahl wird durch die Ausfallsrichtung μ, die Divergenz Γ, der Intensität N und des Anteils umgeladener Teilchen charakterisiert. Es wird die Abhängigkeit dieser charakteristischen Eigenschaften von der in die Kapillaren eingetragen Ladung untersucht. Weiterhin erfolgt eine exponentielle Annäherung an die Gleichgewichtswerte mit der Aufladungskonstante ρ. Die Aufladungskonstante wächst mit steigendem Anstellwinkel und steigender kinetischer Energie der einfallenden Teilchen, ist aber für alle oben genannten Eigenschaften des ausfallenden Ionenstrahls gleich. Erstmalig werden gleichzeitig alle oben genannten Eigenschaften des transportierten Ionenstrahls in Abhängigkeit von der kinetischen Energie der einfallenden Teilchen untersucht. Die Energieabhängigkeit der Eigenschaften des übertragenen Ionenstrahls wird mit einer exponentiellen Annäherung an einen Grenzwert für hohe kinetische Energien beschrieben und durch den Parameter charakterisiert. Dieser ist für alle Eigenschaften des ausfallenden Ionenstrahls im Rahmen des Messfehlers gleich. Die in dieser Arbeit im Bereich von Ekin. = q · 630 eV bis Ekin. = q · 5600 eV gemessene exponentielle Abhängigkeit des Guiding-Prozesses von der kinetischen Energie unterscheidet sich von der in der Literatur zu findenden Abhängigkeit. Die Divergenz des ausfallenden Ionenstrahls wird gesondert betrachtet. Die Experimente zeigen eine größere Divergenz des ausfallenden Ionenstrahls in Ablenkrichtung als senkrecht zur Ablenkrichtung. Die Strahldivergenz senkrecht zur Ablenkrichtung steigt im untersuchten Energiebereich mit steigendem Anstellwinkel. In Ablenkrichtung wird in Abhängigkeit von der kinetischen Energie eine unterschiedliche Abhängigkeit der Divergenz vom Anstellwinkel gemessen. Das Verhalten wird unter Berücksichtigung des Guiding-Modells diskutiert. Untersuchungen hinsichtlich einer möglichen technischen Anwendbarkeit des Guiding-Prozesses führen zu differenzierten Ergebnissen. Die Messungen mittels einer aus einer Nanokapillarfolie geformten Linse zeigen ein geringes technischen Potenzial, da die Fokussierung des einfallenden Strahls durch die Divergenz des ausfallenden Ionenstrahls kompensiert wird. Im Gegensatz dazu zeigt die Verwendung einer makroskopischen Glaskapillare ein großes Anwendungspotenzial. Die Ionenstromdichte des einfallenden Ionenstrahls konnte mit einer konischen Glaskapillare um den Faktor 8 erhöht werden. Durch die Realisierung eines Potenzialunterschieds zwischen dem Ein- und Ausgang einer makroskopischen Kapillare wird ein Ionenstrahl innerhalb der Kapillare abgebremst. Es wird gezeigt, dass der Guiding-Effekt die Aufweitung des Ionenstrahls während der Abbremsung effektiv verhindert. Dies ermöglicht die Konstruktion einer kompakten Ionenabbremseinheit.
266

Post Divorce Experience Of Higly Educated And Professional Women

Kavas, Serap Turkmen 01 July 2010 (has links) (PDF)
ABSTRACT POST-DIVORCE EXPERIENCE OF HIGHLY EDUCATED AND PROFESSIONAL WOMEN Kavas, Serap Ph.D., Department of Sociology Supervisor: Assoc. Prof. Ayse Gunduz Hosgor July 2010, 327 pages Based on life-story interviews with women this dissertation analyzes post divorce experience of highly-educated and professional women. Economic, social, psychological well-being of divorced women / specifically, how they manage to adapt to their new lives after legal dissolution were examined. As is shown in our research while divorce caused various difficulties including financial, social and parenting problems, it, on ther other hand provided relief, for the participants. The participants developed wide range of survival strategies in the face of difficulties and challenges they experience which attested to their agency during and after the divorce process. To the study, while an urbanite, educated and professional woman&rsquo / s termination of a failing relationship itself can be considered as liberation on her part, it will be an overstatement to say that women are enjoying their independence and start anew, just as men do. In this connection, this study searched for insights into the question: How does act of divorce affect these women with respect to their empowerment? Feminist theory is used over the duration of this study. The study scrutinized on the emergent themes such as societal attitudes, single parenting, remarriage, intergenerational and intra-family transmission of divorce, financial consequence, and women&rsquo / s varying coping strategies as well as many other common themes emerged. Studying post-divorce experience of women, which is an unexplored area in Turkish context, employing qualitative method and dwelling on grounded theory approach as an inductive way of data analysis, this study intends to be a considerable contribution to the literature.
267

Physical activity levels among people living with HIV/AIDS treated with high active antiretroviral therapy in Rwanda

Augustin, Murenzi January 2011 (has links)
The current study aims to determine physical activity levels among people living with HIV treated with high active antiretroviral therapy in Kigali, Rwanda. A cross-sectional design using quantitative method was used. The participant’s levels of physical activity participation and their association with anthropometric profiles were measured, using a structured selfadministered questionnaire adapted from the Sub-Saharan Africa Activity Questionnaire. Based on a scientific calculation, 407 clients passing through the clinics were included in the study. A convenient sample of people attending the clinics approached to participate voluntarily in the study. The findings of the current study highlighted the lack of motivation, lack of time and fear of worsening the disease amongst the strong barriers to physical activity participation. The current study recommends education about the benefits of physical activity participation and encouragement of patient treated with high active antiretroviral therapy in Rwanda to be emphasized on to improve their lives.
268

Den högkänsliga personens hälsa och koppling till naturen / The highly sensitive persons' health and connection to nature

Lutvica, Nina January 2015 (has links)
Högkänslighet, eller så kallad sensory-processing sensitivity (SPS), har beskrivits som ett personlighetsdrag där individen bearbetar sensorisk information på ett djupare och starkare sätt än personer som inte är högkänsliga. Syftet med den aktuella studien var att, med hjälp av självskattningsformuläret ”the Highly Sensitive Person Scale” (HSP), undersöka högkänslighet mot skattningar av naturen (NR, NR-Self, NR-Perspective, NR-Experience), grubbleri (RRQ-Rumination) och självreflektion (RRQ-Reflection), subjektivt välbefinnande (WHO) och upplevelser av mindfulness (MAAS). Undersökningen skedde via en webb-baserad enkät och omfattade 213 deltagare. Resultatet visade att individer som är mer högkänsliga värderar naturen högre, samt grubblar och reflekterar mer kring sig själva, än mindre högkänsliga personer. Inga signifikanta skillnader förelåg mellan grupperna vad gäller mindfulness eller välbefinnande. Resultatet tyder på att både en interaktion med naturen och mindfulness kan vara gynnsamt för högkänsliga individer. Denna studie kan utgöra en startpunkt för framtida forskning, där experimentella studier med upprepad mätning kan genomföras för att undersöka naturens roll för högkänsliga personer. / Sensory-processing sensitivity (SPS) has been described as a personality trait where the individual process sensory information in a deeper and stronger way than people who are not highly sensitive. The aim of the present study was to, with the self-assessment form ”the Highly Sensitive Person Scale” (HSP), examine sensory-processing sensitivity against evaluations of nature (NR, NR-Self, NR-Perspective, NR-Experience), rumination (RRQ-Rumination) and self-reflection (RRQ-Reflection), subjective well-being (WHO) and experiences of mindfulness (MAAS). The survey was done through a web-based questionnaire and included 213 participants. The results showed that individuals who are more highly sensitive value nature higher, and also ruminate and reflect more on themselves, than people who are less highly sensitive. No significant differences existed between the groups concerning mindfulness or subjective well-being. The results suggest that both an interaction with nature and mindfulness can be favourable for highly sensitive persons. This study can serve as a starting point for future research, where experimental studies with repeated measures can be conducted to investigate the role of nature for highly sensitive persons.
269

The TITAN electron beam ion trap: assembly, characterization, and first tests

Froese, Michael Wayne 19 September 2006 (has links)
The precision of mass measurements in a Penning trap is directly proportional to an ion's charge state and can be increased by using highly charged ions (HCI) from an Electron Beam Ion Trap (EBIT). By bombarding the injected and trapped singly charged ions with an intense electron beam, the charge state of the ions is rapidly increased. To use this method for short-lived isotopes, very high electron beam current densities are required of the TITAN EBIT, built and commissioned at the Max-Planck-Institute for Nuclear Physics in Heidelberg, Germany and transported to TRIUMF for the TITAN on-line facility. This EBIT has produced charge states as high as Kr34+ and Ba54+ with electron beams of up to 500 mA and 27 keV. Once the EBIT is operational at full capacity (5 A, 60 keV), most species can be bred into a He-like configuration within tens of ms.
270

Modelling the Effects of Seston Food Quality on Zooplankton Growth: Implications for Broader food Web Dynamics

Perhar, Gurbir 19 December 2012 (has links)
An increasing number of contemporary studies in aquatic ecology emphasize the im- portance of highly unsaturated fatty acids (HUFAs) at the plant-animal interface. Studies have demonstrated a wide range of fatty acid profiles in primary producers, forcing her- bivorous zooplankton to differentially retain fatty acids to meet somatic requirements. Herbivores also vary in their somatic fatty acid profiles; cladocerans collect Eicosapen- taenoic Acid (EPA), copepods prefer Docosahexaenoic Acid (DHA). Fatty acid internal reserves can be broken down to meet structural needs (i.e. phospholipid synthesis), fuel reproduction and may play a role in cold weather adaptation. Several authors have noted increases in HUFA concentration with lowering ambient temperatures. Cladoceran membranes form a gel at lower temperatures, while copepod membranes remain fluid and allow active overwintering. Both fish and crustaceans accumulate high concentrations of HUFAs during periods of rapid growth, but colimitation with elemental resources may exist. Recent modeling results suggest food webs with high quality (nutritional and biochemical) primary producers can attain inverted biomass distributions with efficient energy transfer between trophic levels. The adoption rate for this material into man- agement studies remains low, and while other sectors of the scientific community thrive on the potential of HUFAs, planktonic food-web studies are choosing traditional view points over forward thinking. Bearing in mind the emerging hypotheses on the critical factors that drive the energy flow in the plant-animal interface, my dissertation will at- tempt to address the following general questions: What are the distinct signatures of food quality and food quantity on planktonic food web dynamics? How do nutritional and biochemical factors affect the flow of energy at the plant-animal interface? What is our current understanding of the role of highly unsaturated fatty acids (HUFAs) in aquatic food webs? To what extent can the current generation of plankton models reproduce the lower food web patterns when explicitly accounting for HUFAs? Is the integration of the HUFA role into water quality management models feasible? Explicitly accounting for HUFAs requires integrating factors of animal physiology with macro-ecology: what are the ramifications? Finally, what are the evolutionary aspects of animals coping with food quality?

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