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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.
11

Qualified clinical psychologists' experiences of working with children with life-limiting conditions : a qualitative study

Davenport, Rebecca Kate January 2012 (has links)
Background: Despite the increased presence of clinical psychologists in paediatric services, including palliative care teams, there has been little research into their experience of working with children with life-limiting conditions. Existing studies have tended to focus mainly on the experience of medical professionals working in this area. Such studies have found that working with life-limiting conditions and child death has a significant impact on medical professionals, causing stress, burnout and feelings of professional failure. As clinical psychologists have a role in supporting the emotional needs of children, families and staff teams, it is important to explore their experiences, the impact that such work has on them, and any potential personal and professional implications. Aims: After identifying the above gap in the research, this study aimed to explore clinical psychologists‟ experiences of working with children with life-limiting conditions. Method: Semi-structured interviews were conducted with seven qualified clinical psychologists who were working in hospital settings with children with life-limiting conditions. The transcripts of the interviews were then analysed using Interpretative Phenomenological Analysis (IPA). Results: Three superordinate themes emerged from the analysis: „The meeting of two worlds: When psychology and medicine converge‟, „Nobody is immune: Facing the challenges of working of life-limiting conditions‟ and „Balancing the rough with the smooth: Finding a way to manage‟. Implications & conclusion: Participants experienced challenges in having to adapt to a medical world and in facing emotional impacts however, they also reported positive experiences from their work. The study raised many implications for clinical practice including the need to potentially help psychologists to prepare for the possible changes required when practicing in a hospital setting. This could perhaps be incorporated more into clinical training or be provided as in-house training when starting in the post.
12

Control of marine plankton respiration : High temperature sensitivity at low temperatures influenced by substrate availability

Amundsson, Katharina January 2016 (has links)
Temperature dependence of marine plankton respiration is an important factor in understanding the function and changes in the ecosystem of the ocean. The aim of this study is to test the temperature sensitivity (Q10) of plankton respiration. The oxygen optode method was used to measure plankton respiration. Natural water samples from the Baltic Sea was incubated at short (in situ +1, +2, +3°C) and long (in situ +5, +10, +20°C) temperature intervals with influence of dissolved organic matter (DOC). The Arrhenius equation and Q10-model was used to determine the temperature dependence (Q10) of respiration at different temperatures. There was a significant difference in Q10 between short temperature intervals at low temperatures (p=0,008) and long temperature intervals at higher temperatures. There was no significant difference between long and short temperature intervals when DOC was added (p=0,094). A significant effect could be seen with the DOC enrichment at low temperatures, where the Q10-values became significantly lower (p=0,002) after DOC addition. This effect could, however, not be seen at higher temperatures (p=0,117). Together with results from earlier studies it was concluded that the difference in temperature depends on the actual temperature and not the length of the interval. Lowered temperature dependence at raised DOC concentration, was the opposite of what was expected. The results suggest that the importance of temperature for CO2 emissions and development of hypoxia in the sea may have been underestimated.
13

Surgical outcomes of pars plana vitrectomy with and without internal limiting membrane peeling for symptomatic vitreomacular traction

Stern, Adam 12 July 2017 (has links)
PURPOSE: To study the long-term anatomic and visual outcomes after pars plana vitrectomy (PPV) with and without internal limiting membrane (ILM) peeling in patients with symptomatic vitreomacular traction (VMT). This study assesses the frequency of complications, changes in visual acuity, and changes in anatomical central macular thickness after macular surgery. METHODS: This retrospective, single-site, single-surgeon study reviewed 40 medical records (45 eyes) of patients at the Beth Israel Deaconess Medical Center requiring PPV with ILM peeling (n=27) or without ILM peeling (n=18) for VMT between the years of 2003 and 2016. Successful surgery was defined as the relief of anatomical traction, and the absence of a second surgery, or any post-operative complications (n=42). Visual acuity was documented for each eye prior to surgery and post surgery. RESULTS: All 27 (100%) eyes that had ILM peeling had successfully resolved macular traction following a single surgery, and 15 of the 18 (83.3%) eyes without ILM peel were successful. None of 27 (0%) eyes that had ILM peeling required a second surgery, nor did they have complications. 3 of the 18 (16.7%) eyes without ILM peeling required a second surgery. Best corrected visual acuity (BCVA, logMAR) improved significantly in both groups: BCVA improved from 0.59 ± 0.29 preoperatively to 0.37 ± 0.25 postoperatively in eyes receiving ILM peeling and from 0.77 ± 0.37 to 0.53 ± 0.37 in eyes with PPV only. Mean change in CMT pre-operatively to post-operatively was found to be greater in eyes with PPV alone, but this difference was not statistically significant. CONCLUSIONS: Our case series shows that PPV with ILM peeling for VMT relieved macular traction better than PPV alone, although there was no significant difference in visual acuity outcomes or central macular thickness between the two groups. Further research is required to validate these findings. / 2019-07-11T00:00:00Z
14

Greenalgae as a substrate for biogas production - cultivation and biogas potentials

Liu, Yang January 2010 (has links)
<p>Algae is regarded as a good potential substrate for biogas production, due to high cells productivity, low cellulose and zero lignin content. Two parts were included in this study: first, cultivations of micro-algae (<em>Chlorella sorokiniana</em> and <em>Tetraselmis suecica</em>) at two different nitrate concentrations, also the effect of addition of CO<sub>2</sub> on algae grow was investigated in this first part. Second, batch fermentations of the cultivated micro-algae as well as a powder <em>Chlorella</em> (obtained from Raw Food Shop) and a dry mix filamentous algae (collected in the pounds in the park at the back of the Tema-building and then dried) were performed. In this part also effects of thermo-lime pretreatment (room temperature, 80<sup>o</sup>C, 105<sup>o</sup>C and 120<sup>o</sup>C) on the algae biogas potentials was investigated.</p><p> </p><p>Both strains of micro-algae cultured at low nitrate gave more CH<sub>4</sub> yield: 319 (±26) mL and 258 (±12) mL CH<sub>4 </sub>per added gVS was obtained during the degradation of <em>Chlorella sorokiniana </em>grown at 0.4mM-N and 2mM-N level, respectively. For<em> Tetraselmis suecica</em> 337 (±37) mL and 236 (±20) mL CH<sub>4</sub> per added gVS was obtained at 2.4mM-N and 12mM-N level, respectively. Powder <em>Chlorella</em> gave the highest biogas production (719 ±53 mL/added gVS) and CH<sub>4</sub> yields (392 ±14 mL/added gVS), followed by the dry filamentou<em>s</em> algae (661 ±20 mL biogas and 295 ±9 mL CH<sub>4</sub> per added gVS) and <em>Tetraselmis suecica</em> (12 mM-N; 584 ±7 mL biogas and 295 ±9 mL CH<sub>4</sub> per added gVS).</p><p> </p><p>A negative effect of lime treatment at room temperature on CH<sub>4</sub> yield of algal biomass was obtained. Lime treatment at 120<sup>o</sup>C showed the fastest degradation rate for <em>Tetraselmis</em> <em>suecica </em>and powder <em>Chlorella</em> during the initial 5 days of incubation.  </p><p> </p><p><em>Chlorella sorokiniana</em> and <em>Tetraselmis suecica</em> cultures flushed with biogas containing 70% and also CO<sub>2</sub> enriched air (5% CO<sub>2</sub>) did not increase cells growth (measured as OD<sub>600</sub>) if compared to references grown under air. On the contrary, a clearly inhibition effect on the algal cells growth was observed in some cultures.</p>
15

Distributed Policing with Full Utilization and Rate Guarantees

Choi, Albert C. B. January 2009 (has links)
A network service provider typically sells service at a fixed traffic rate to customers. This rate is enforced by allowing or dropping packets that pass through, in a process called policing. Distributed policing is a version of the problem where a number of policers must limit their combined traffic allowance to the specified rate. The policers must coordinate their behaviour such that customers are fully allowed the rate they pay for, without receiving too much more, while maintaining some semblance of fairness between packets arriving at one policer versus another. A review of prior solutions shows that most use predictions or estimations to heuristically allocate rates, and thus cannot provide any error bounds or guarantees on the achieved rate under all scenarios. Other solutions may suffer from starvation or unfairness under certain traffic demand patterns. We present a new global ``leaky bucket'' approach that provably prevents starvation, guarantees full utilization, and provides a simple upper bound on the rate allowed under any incoming traffic pattern. We find that the algorithm guarantees a minimum 1/n share of the rate for each policer, and achieves close to max-min fairness in many, but not all cases. We also suggest some experimental modifications that could improve the fairness in practice.
16

Distributed Policing with Full Utilization and Rate Guarantees

Choi, Albert C. B. January 2009 (has links)
A network service provider typically sells service at a fixed traffic rate to customers. This rate is enforced by allowing or dropping packets that pass through, in a process called policing. Distributed policing is a version of the problem where a number of policers must limit their combined traffic allowance to the specified rate. The policers must coordinate their behaviour such that customers are fully allowed the rate they pay for, without receiving too much more, while maintaining some semblance of fairness between packets arriving at one policer versus another. A review of prior solutions shows that most use predictions or estimations to heuristically allocate rates, and thus cannot provide any error bounds or guarantees on the achieved rate under all scenarios. Other solutions may suffer from starvation or unfairness under certain traffic demand patterns. We present a new global ``leaky bucket'' approach that provably prevents starvation, guarantees full utilization, and provides a simple upper bound on the rate allowed under any incoming traffic pattern. We find that the algorithm guarantees a minimum 1/n share of the rate for each policer, and achieves close to max-min fairness in many, but not all cases. We also suggest some experimental modifications that could improve the fairness in practice.
17

Nonlinear optical properties of absorbing molecular systems

Robertson, John Michael January 2002 (has links)
No description available.
18

Capacity Constraints for Air Traffic Flow Development

Petersen, Rebecca January 2018 (has links)
In aviation, the demand for air traffic grows at a higher rate than the capacity. As the demand is predicted to continue to grow also in the future, so is the problem of capacity shortage. If the capacity cannot match the demand, it will result in congestion and delay. There are numerous factors that limit the capacity both on airside and landside, for example the runway capacity, noise restrictions, the environment surrounding the airport etc. Actors such as airlines, ground service companies, ICAO and IATA also affect and are affected by the available capacity. When planning opening of new airports or in case of changes in the location and size of the airports, the requirement for, as well as the currently available capacity must be examined. Previous studies regarding key limiting factors to air traffic capacity, address different constraints, but lack a comprehensive view. A compilation of air traffic constraints would therefore be a valuable tool in airport planning when capacity demand changes. The aim of this thesis was to identify key limiting factors and see how they affect air traffic. This thesis analyses the importance of different limiting factors in respect to the level of significance to which previous research has acknowledged the different constraints. To compliment the literature review, professionals in airport planning were interviewed. The result from the literature review as well as the interviews showed that the major limiting factor to air traffic capacity is the runway. The runway was also the factor that was affecting as well was affected by other limiting factors. Previous literature considered wake vortex to be the second most important constraint whereas the interviewees considered stands to be the runner up limiting factor. In conclusion, this thesis showed that the runway is the most important limiting factor to air traffic capacity. The thesis also showed that different limiting factors are closely linked to each other. For an overall understanding of air traffic capacity constraints and how these constraints affect air traffic flow, it is essential to understand the interaction between the limiting factors.
19

Palliative Care: Viewpoints from Nurses

Buttry, Nancy Kyle 01 December 2016 (has links)
TITLE: Palliative Care: Viewpoints from Nurses Palliative Care has been described as care that includes the physical, intellectual, emotional, social, and spiritual needs of an individual when they are diagnosed with a serious or life-limiting illness. The ultimate goal of palliative care is to promote the best quality of life possible. Palliative care should be implemented across the lifespan and across different health care settings. The purpose of this study was to describe the perceptions, impact, and meaning of palliative care from the viewpoint of nurses who provide basic palliative care to patients and their families. This study used a qualitative design to investigate the meaning, experiences, and feelings of nurses who provide palliative care in small or critical access hospitals and other agencies in this rural area. Three focus groups and eleven interviews were conducted with nurses working in a variety of agencies from October 2015 to February 2016. The four themes that emerged from the data included inconsistencies, knowledge deficits, communication issues, and emotional responses and rewards to providing palliative care. The themes focused on the need for clarification of the meaning of palliative care, more education on the topic and better communication. The nurses shared that it was rewarding to provide palliative care but identified barriers that they felt should be addressed. Nurses participating in the study did not perceive that they had palliative care at their agencies. Recommendations included that more health education about palliative care be provided to healthcare professionals, the community, and individuals with life-limiting illnesses and their families. Key words: palliative care, quality of life, life-limiting illness, nursing
20

ProspecÃÃo de Cylindrospermopsis Raciborskii em ReservatÃrios no Cearà e Efeitos da DepleÃÃo de Nutrientes na sua ConcentraÃÃo Celular / Prospecting Cylindrospermopsis raciborskii in reservoirs in Cearà and Effects of Nutrient Depletion in your Cell Concentration

MÃrio Ubirajara GonÃalves Barros 22 March 2013 (has links)
CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / A qualidade da Ãgua dos reservatÃrios brasileiros vem sendo comprometida devido ao intenso processo de eutrofizaÃÃo. O lanÃamento de esgoto sanitÃrio, a agropecuÃria e a piscicultura intensiva favorecem esse fenÃmeno pela introduÃÃo no meio aquÃtico de altas concentraÃÃes de nutrientes, principalmente o nitrogÃnio e o fÃsforo. A eutrofizaÃÃo da Ãgua prejudica o abastecimento pÃblico pelo fato de favorecer a proliferaÃÃo de cianobactÃrias potencialmente produtora de toxinas. O presente trabalho teve como objetivo realizar um mapeamento das cianobactÃrias potencialmente produtora de toxinas, especificamente a espÃcie Cylindrospermopsis raciborskii, em mananciais utilizados para abastecimento pÃblico no estado do CearÃ. Os dados necessÃrios para a prospecÃÃo do fitoplÃncton nos reservatÃrios do Cearà foram coletados no laboratÃrio central da Companhia de Ãgua e Esgoto do Cearà (CAGECE). Avaliou-se tambÃm a influÃncia da depleÃÃo de nutrientes limitantes no desenvolvimento de culturas da C. raciborskii T3. Os experimentos foram realizados utilizando-se como meio de cultivo o ASM-1 e variaÃÃes do mesmo com a retirada de 75 e 50% de fÃsforo e nitrogÃnio da sua composiÃÃo inicial. As culturas foram desenvolvidas em condiÃÃes nÃo axÃnicas, mantidas sob intensidade luminosa constante de 6,75 &#956;.mol.m-2.s-1 submetidas à fotoperÃodo de 12h:12h e temperatura de 24Â2 ÂC. O mapeamento da comunidade fitoplanctÃnica nos reservatÃrios estudados apresentou dominÃncia de cianobactÃrias, frequentemente maiores que 90% do fitoplÃncton total. Com relaÃÃo à cianobactÃria C. raciborskii, sua presenÃa foi evidenciada em todos os reservatÃrios estudados, com menor representaÃÃo no aÃude Cedro (30%) e maior no AÃude Carmina (98%). Em todos os aÃudes, exceto o AÃude Cedro, a presenÃa do gÃnero C. raciborskii foi, em mÃdia, maior que 70% durante todo o perÃodo estudado. A dominÃncia dessa espÃcie foi evidenciada em trÃs reservatÃrios: aÃude Acarape do Meio (92%), aÃude Serafim Dias (89%) e aÃude do Coronel (73%) e em dois reservatÃrios, aÃude SÃtios Novos e aÃude Cedro, esta espÃcie nÃo dominou em nenhuma coleta. Os resultados mostraram tambÃm que as culturas com depleÃÃo de nitrogÃnio apresentaram nitidamente menor crescimento com relaÃÃo aos outros experimentos, atingindo a fase estacionÃria mais cedo e com menores concentraÃÃes celulares. Jà as culturas com depleÃÃo de fÃsforo (75 e 50% P) apresentaram curvas de crescimento mais acentuadas, demonstrando assim que o elemento nitrogÃnio foi limitante para o crescimento da C. raciborskii nas condiÃÃes deste experimento. / The water quality of Brazilian reservoirs has been harmful due to the intense process of eutrophication. Wastewater, agriculture and intensive farming favor this phenomenon by introducing into the aquatic environment high concentrations of nutrients, particularly nitrogen and phosphorus. Eutrophication of water affect the public water supply because induces proliferation of cyanobacteria potentially toxins producer. This study aimed to perform a mapping of cyanobacteria potentially toxins producer, specifically Cylindrospermopsis raciborskii, in reservoirs used for public supply in the state of CearÃ. Data were collected in the central laboratory of Water and Wastewater Company of Cearà (CAGECE). We also evaluated the effect of depletion of limiting nutrients in the growth of C. raciborskii T3. The experiments were performed using as the culture medium ASM-1 and variations of it with the removal of 75% and 50% of phosphorus and nitrogen from its initial composition. Cultures were grown in axenic conditions and maintained under constant light intensity of 6.75&#956;.mol.m-2.s-1, subjected to photoperiod of 12h: 12h and 24  2  C. The mapping of phytoplankton in reservoirs studied showed dominance of cyanobacteria, often greater than 90% of the total cell concentration. Regarding the cyanobacterium C.raciborskii, its presence was evident in all reservoirs studied, with less representation in Cedro (30%) and higher in Carmina (98%). In all reservoirs except Cedro, the presence of the genus C. raciborskii was on average greater than 70% throughout the study period. The dominance of this species was found in three reservoirs: Acarape do Meio (92%), Serafin Dias (89%) and Coronel (73%) and two reservoirs, Sitios Novos and Cedro, this species did not dominated in any campaign. The results also showed that the nitrogen-depleted cultures showed significantly lower growth relative to other experiments, reaching the stationary phase sooner and at lower cell concentrations. Cultures with depletion of phosphorous (75%P and 50%P) showed more pronounced growth curves, showing that the element nitrogen was limiting the growth of C. raciborskii in this experiment.

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