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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.
311

Marina maktdemonstrationer och tvångsutövning : En studie om örlogsfartygs påverkan på utfallet av marint tvång.

Blandford, Petter January 2023 (has links)
Present naval disputes indicates that naval compellence has endured since imperial expansionism and is still an active part of nation’s maritime diplomacy and strategy. In this study, I argue that sea power is more than a symbol of the aggressor’s national power and have a substantial impact on the outcome of naval compellence. Due to the exclusiveness of specific types of warships, the strategic prioritisation creates strategic cost that can signal resolve and credibility as sunk cost. Submarines also creates the opportunity for private signalling, without public transparency. Combining data from multiple datasets that compares the outcome of naval compellence between 1918-2011 with the naval power of the aggressor, this study presents systematic evidence that battleships increase the probability of successful naval compellence while carriers, conventional and nuclear submarines can’t be proven to have a significant impact on the outcome.
312

Evaluación del impacto ambiental del efluente submarino del proyecto Provisur empleando el modelo Cormix

Vargas Torres, José Alonso 01 October 2018 (has links)
En el Perú, se tiene una buena riqueza hídrica pues se cuentan con 54 cuencas hidrográficas por las que se podrían obtener 2’046,827 metros cúbicos al año. Sin embargo, este recurso hídrico está localizado en lugares con menor densidad poblacional y no alcanza suficientemente a los lugares de mayor densidad poblacional que usualmente se ubican en la costa. Una alternativa de solución para la escasez de agua potable son las plantas desalinizadoras. Por esta razón, en el sur de Lima, se está construyendo una planta desalinizadora y una planta de tratamiento de agua residual para beneficiar directamente a los usuarios en los distritos del sur. Este proyecto, llamado PROVISUR, está siendo cuestionado por una presumible contaminación a las playas en Santa María. Por lo antes expuesto, la presente tesis tiene como objetivo estudiar el funcionamiento de una planta desalinizadora de Osmosis Inversa y de una Planta de Tratamiento de Aguas Residuales para entender el proyecto de PROVISUR. Así como también, analizar todos los impactos ambientales que son producidos por este proyecto en el mar peruano y proponer soluciones y alternativas en específico al vertimiento del efluente de ambas plantas. Finalmente, modelar la emisión mediante el programa CORMIX y determinar los impactos ambientales reales de las plantas del proyecto ubicado en el balneario de Santa María, Lima. Después de estudiar el Estudio de Impacto Ambiental del proyecto PROVISUR y de realizar el modelamiento numérico empleando el CORMIX, se tiene como conclusión, que este proyecto tendría que ser revisado por las autoridades correspondientes debido a que presenta algunas deficiencias en el Marco Legal y presenta imperfecciones en el modelamiento para la dispersión del contaminante. Los valores obtenidos después de la modelación numérica son aproximados al estudio realizado por la empresa PROVISUR en cuanto a los parámetros ambientales. Sin embargo, estos contaminantes no están siendo analizados apropiadamente para una dilución en un campo cercano a la emisión.
313

The Response of Marine Synechococcus to a Landscape of Environmental Stressors: A Proteomic Exploration

Michels, Dana E 01 March 2021 (has links) (PDF)
In the field of marine microbial ecology, many questions remain unanswered with regards to the physiological trade-offs made by phytoplankton to maximize growth (e.g., nutrient acquisition) and minimize loss (e.g., predation defenses). These tradeoffs, which occur at the cellular level, have wide reaching impacts on food web dynamics and global biogeochemical cycles. In the first chapter, we explored the use of a non-canonical amino acid (NCAA) technique, bioorthogonal non-canonical amino-acid tagging (BONCAT), in phytoplankton model systems. This technique has potential to work well in natural systems by enabling isolation of only newly synthesized proteins during an incubation period with the NCAA, reducing the complexity of natural proteomics and easing the elucidation of patterns. However, in testing BONCAT across several groups of cultured phytoplankton, we discovered that the NCAA molecule induced a stress response in the globally ubiquitous marine picocyanobacteria, Synechococcus sp. Therefore, in addition to confirming the uptake of modified amino acids by phytoplankton, chapter one investigated the implications of this stress response and limitations when using this technique to study marine microbial communities. In chapter two, we addressed our initial question by exploring tradeoffs at the protein level in a simplified culture system. This approach revealed insights into metabolic tradeoffs in response to predation pressure and nutrient stress. These insights into how phytoplankton negotiate these physiological tradeoffs at the protein level could ultimately allow for targeted proteomic studies in natural systems.
314

Desarrollo de metodologías para la cuantificación de residuos plásticos que ingresan al océano y su influencia en el agotamiento de recursos abióticos

Ita Nagy, Diana 25 August 2023 (has links)
En los últimos años, ha habido un aumento significativo en la atención internacional hacia la acumulación de plásticos en el mar. Aunque se han realizado esfuerzos para cuantificar fuentes y cantidades exactas de residuos, así como entender sus impactos, estos intentos siguen siendo limitados. Para abordar esta problemática, herramientas como el Análisis de Ciclo de Vida (ACV) deben ser mejoradas e incluir indicadores que estén relacionados con el potencial daño ambiental de las partículas plásticas en la naturaleza. Además, se requiere el desarrollo de inventarios de ciclo de vida (ICV) que contemplen los flujos de plásticos mal gestionados que ingresan al medio ambiente. En este contexto, esta tesis de doctorado presenta dos objetivos principales. Por un lado, diseñar una metodología para la cuantificación de flujos plásticos que estarían entrando al océano desde fuentes terrestres, con el fin de impulsar la creación de ICVs que los incluyan. Por otro lado, desarrollar una categoría de impacto de agotamiento de recursos abióticos que considere el efecto de la disipación de polímeros plásticos en la naturaleza. La primera parte del estudio permitió identificar diferentes barreras antrópicas y naturales que afectan el movimiento de los residuos hacia el mar, y diseñar una ecuación que ilustre la relevancia de los efectos de retención de plásticos. En la segunda parte, se desarrolló una categoría de impacto ambiental para cuantificar las consecuencias de estos flujos de materiales mal manejados dentro del ACV. La categoría de impacto, llamada marine circularity loss, cuantifica la pérdida de materiales plásticos en el océano que no podrían reingresar a la cadena de valor. Se espera que estos avances en la cuantificación de flujos de residuos plásticos y sus impactos en el océano permitan una toma de decisiones más adecuada frente a esta situación. / In recent years, the accumulation of marine plastic has gained international attention. However, attempts to quantify sources, magnitudes, and related impacts of marine waste in a more precise way are still limited. It is important that tools, such as the Life Cycle Assessment (LCA), include linkages to the potential environmental damage generated by plastic particles in nature. Likewise, life cycle inventories (LCI) must be developed including flows of mismanaged plastics that enter nature. In this context, this doctoral thesis has two main objectives. On the one hand, to design a methodology for the quantification of plastic flows that may be entering the ocean from terrestrial sources, in order to promote the creation of ICVs that include them. On the other hand, the development of an abiotic resource depletion impact category which considers the effect of the dissipation of plastic polymers in nature. The first part of the study made it possible to identify different anthropogenic and natural barriers that affect the movement of waste towards the sea, and to design an equation that allowed illustrating the relevance of the effects of plastic retention. The second part, an environmental impact category to quantify the consequences of these mismanaged material flows within the LCA was developed. The impact category, called marine circularity loss, quantifies the loss of plastic materials in the ocean that are not able to re-enter the economic value chain. It is expected that these advances in the quantification of plastic waste flows and their impacts on the ocean will allow for more appropriate decision-making to address this situation.
315

Does eutrophication cause greater growth of epiphytic algae on the seagrass Zostera marina?

Ljung, Angelica January 2024 (has links)
The most common eelgrass along the Swedish coast is Zostera marina. It is an ecosystem engineer which provides both nature and humans with important ecosystem services and various ecosystem functions. Eutrophication is one of the main reasons why the Swedish coast has lost a lot of Z. marina meadows. When there is more nitrogen in the ocean, it is an advantage for epiphytic algae so that they can grow faster. The epiphytic algae grow on Z. marina and reduce Z. marina from receiving light. And therefore, the aim of my thesis is to investigate the effect of eutrophication on the growth of epiphytic algae on Z. marina. I took water samples at 8 different locations (spanning 7.21 km) along the coast of Halmstad, from the mouth of river Nissan, which I hypothesize to be a main source of nitrogen, to the open sea. From the water samples nitrogen, absorbance and TOC was measured to see if there was any difference in the water composition from Nissan's outlet and seawards. Z. marina leaves were taken from two different sites on one occasion to investigate the degree of epiphytic algae on the leaves. I found that the nitrogen concentration was decreasing from the outlet of Nissan River along coast towards the open sea. Also, the growth of epiphytic algae on Z. marina was decreasing from the outlet of Nissan River along the coast towards the open sea. The growth of epiphytic algae on Z. marina was not solely dependent of the concentration of nitrogen. In Scandinavia, Z. marina meadows are one of the most diverse coastal ecosystems. On otherwise sandy and species-poor substrates, Z. marina is an important habitat for a rich epiflora and fauna so a more integrated understanding in both management and science of Z. marina's stress responses is needed.
316

Challenges of antiretroviral medication adherence in HIV/AIDS-infected women in Botswana

Mabuse, Magdeline 11 1900 (has links)
This study using a quantitative, descriptive design with a questionnaire investigated cultural, religious and social factors that might impact on ARV treatment in HIV/AIDS-infected women in Botswana. The study found that the majority never missed any doses, a few missed doses once or twice, and a small minority missed more than three times. The respondents’ perception of cultural influence on treatment of HIV/AIDS in women revealed that the majority (70%) believe culture has an influence on the treatment. Social factors also impacted on ARV adherence. A few of the respondents indicated that side effects and the number of pills prevented ARV medication adherence. The main reason for non-adherence, however, was forgetfulness. There had been an improvement in the majority of the respondents’ health status and quality of life. Maximizing adherence is essential. Providers and patients both have responsibilities in this regard. / Health Studies / M.A.(Health Studies)
317

Factors affecting antiretroviral therapy patients' data quality at Princess Marina Hospital pharmacy in Botswana

Tesema, Hana Tsegaye 04 June 2015 (has links)
AIM: This study aimed to explore the factors influencing antiretroviral therapy patients` data quality at Princess Marina Hospital Pharmacy in Botswana. METHODS: A phenomenological approach was adopted in this study. Specifically, Interpretative Phenomenological Analysis qualitative design was used to explore the factors influencing antiretroviral therapy patients` data quality at Princess Marina Hospital Pharmacy in Botswana. Data were collected using a semi-structured interview format on 18 conveniently selected pharmacy staff. Data were analysed using Smith’s (2005) Interpretative Phenomenological Analysis framework. RESULT: Five thematic categories emerged from data analysis: data capturing: an extra task, knowledge and experience of IPMS, training and education, mentoring and supervision, and data quality: impact on patients’ care. The findings of this study have implications for practice, training and research. CONCLUSION: Pharmacy staff had limited knowledge of IPMS and its utilisation in data capturing. Such limitations have implications in the context of the quality of data captured / Health Studies / M.A. (Health Studies)
318

The long-term effects of Sargassum muticum (Yendo) Fensholt invasion on Zostera marina L. and its associated epibiota

DeAmicis, Stacey Lynn January 2012 (has links)
In this thesis I review how Sargassum muticum (Yendo) Fensholt, an invasive alga from Asia, has spread globally due to human activities and describe how this species can affect seagrass ecosystems. Abiotic factors such as nutrient and substratum availability may facilitate the spread of S. muticum into Zostera marina L. meadows, but analyses of seawater nutrients, and sediment particle size and % organic content revealed no significant differences between experimental quadrats in seagrass meadows either with, or without the presence of S. muticum. Phenolic compounds were examined because they form the basis of defensive mechanisms in plants and algae, therefore any change in phenolic content may affect the ability of Z. marina to protect itself from disease, herbivory and invasive species through allelopathic interactions. Results from a four year field study and multiple annual laboratory experiments showed significant reductions (p = 0.034 and p = 0.002, respectively) in the caffeic and tannic acids equivalents content of Z. marina when in the presence of S. muticum. As the abundance of S. muticum increases, other changes in the physiology of Z. marina may occur including variations in growth rates, nutrient partitioning and chlorophyll fluorescence, but data from multiple laboratory experiments illustrated no significant differences in growth. Chlorophyll fluorescence analyses revealed significant differences between treatments with and without S. muticum (p = 0.008), but pairwise comparisons indicated these differences only occurred in 2008 (p < 0.001). Significant differences were also found in nutrient partitioning amongst functional regions of the shoots (p = 0.024), but pairwise comparisons detected these differences between a biomass control treatment (ZZ: Zostera + Zostera) and the ZS (with S. muticum) and ZM (Z. marina on its own at a lower biomass per replicate) treatments (p = 0.013 and p = 0.019, respectively), but not between ZS and ZM. Previous in situ research has found negative effects of S. muticum presence on densities of kelp and other algae. Results from the long-term field study indicated significantly lower mean in situ Z. marina densities within the ZS treatment (p < 0.001). Epibiota found living on the blades of Z. marina provide food for organisms within seagrass ecosystems and also create microhabitats for other species to occupy. Alterations in the abundances of epibiota and microhabitats formed could further modify seagrass ecosystems through shifts in timing of food availability, food preferences and microhabitats created. The long-term field study data revealed significantly lower epibiota abundances within the ZS treatment (p = 0.019), but differences in biomass between treatments were not detected. Changes in the biochemistry, physiology, vegetative physiognomy and epibiota assemblages of Z. marina revealed during experimental manipulations are presented and considered within the context of long-term seagrass survival in light of increasing S. muticum invasion.
319

Orenat avloppsutsläpp på Svalbard : En studie om ansvarstagande över marina miljöer i Arktis

Olsson Qvist, Jennie January 2016 (has links)
Svalbard är en arktisk ögrupp i Norra ishavet som förvaltas av Norge och huvudorten är Longyearbyen. I Longyearbyen och som på alla andra platser pågår förorenande aktiviteter, denna rapport är avgränsad till utsläpp via avloppsvatten till marina miljöer. I Arktis märks klimatförändringarna tydligt, det finns många olika styrmedel som skulle kunna förhindra föroreningen av dessa sårbara områden. Styrmedel som det visat sig under arbetet med den här rapporten inte fungerar som det var tänkt, med åsyftan på avloppshanteringen i Longyearbyen. Det finns inget avloppsreningsverk i byn där det bor ca 2300 fastboende och gästdygnen uppgick år 2015 till 128 000. Utsläppet av det orenade avloppsvattnet ut i Adventfjorden tillåts av det kravställande organet Sysselmannen på Svalbard, som gett kommunen tillstånd med lagstöd i Svalbardmiljöloven, att systematiskt släppa ut det förorenade avloppsvattnet. Målet med denna rapport är att undersöka den nuvarande utsläppssituationen med gällande styrmedel och att förstå varför tillståndet till utsläppet av det orenade avloppsvattnet getts. Resultatet visar att formuleringen av handlingsregler och avsaknad av delmål, indikatorer och återkopplingsmekanismer för genomdrivande av styrmedel, är anledningen till varför styrmedlet inte fungerar som tänkt. Detta viktiga resultat kan leda till en förändring vid genomdrivandet av styrmedlet, så att det kan uppnå sin fulla potential. Med klara och tydliga målsättningar vid utformandet av styrmedel uppnår de sina syften. Kontentan av den här rapporten är att styrmedel som används på rätt sätt kan beskydda de sårbara Arktiska marina miljöerna. / Svalbard is an Arctic Archipelago in the Arctic Ocean that is governed by Norway and the main city is Longyearbyen. In Longyearbyen, much like any other place, there is contaminating activities going on. This report is concentrated on the emissions via sewage water into marine environments. In the Arctic, climate change is very noticeable and there are many different instruments that could prevent the pollution of these vulnerable areas. During the time working on this report these instruments have shown that they are not functioning as supposed, with regards to the sewage management in Longyearbyen. There is no sewerage in the town which inhabits 2300 permanent residents and where there were, in the year of 2015, 128 000 overnight stays of tourists. The pollution of the unfiltered sewage water allowed into Adventfjorden has been permitted by the governing organisation, Sysselmannen on Svalbard. Sysselmannen has given the municipality permission with support from the environmental protection law of Svalbard (Svalbardmiljøloven) to systematically release the polluted water into the marine environments. The goal with this report is to examine the current pollution situation with the existing governance and to understand why it has been permitted to release untreated sewage water into the fjord. The result shows that the reason there is an implementation deficit is because of the formulation of the action rules, no clear milestones and the lack of feedback mechanisms in the enforcement. This important result can lead to changed governance so that it could reach its full potential. By keeping the goals clear when designing the enforcement they can achieve their goals. The conclusion of this report is that an implementation of governance can protect the vulnerable Arctic marine environments. / <p>2016-06-29</p>
320

Performing Kongwu's (空無, Emptiness, Nothingness) attitude towards language, time, and self : responding to Nam June Paik, John Cage, and Marina Abramović

Ho, I-Lien January 2014 (has links)
Since 1950s, the concept of Kongwu (空無, Emptiness, Nothingness) has migrated into American-European experimental performances, including those of John Cage and Cage-influenced artists who developed Happenings, Fluxus, and intermedia practices. This research-through-practice investigates how the concept of kongwu, an intercultural synthesis of Chinese Daoism and Indian Buddhism, may shape the principles underlying performance making and how performance may, in turn, elucidate Kongwu way of making sense the world. The installation-performance, Poem without Language contemplates Kongwu’s distrust of language by undermining the communicative purpose of writing and responds to Nam June Paik’s approach to media language. The research practice, One Street, Three Persons, Different Narratives, and Different Memories responds to John Cage’s use of silence to revise time and measurement, and exposes the habit, how we experience the ‘present’ as accumulations of the past, and how we order experiences as a linear continuity, which we call ‘time’. My performance, … is Present suggests different definitions of the ‘meditative mind’ and ‘being-here-and-now’ and critiques the relationship between embodiment and identity in Marina Abramović’s construction of ‘suchness’. Three works offer one response to the poetics and politics of intercultural encounters in the context of Chan/Zen in intermedia performance. My research-through-practice sheds light on Kongwu way of experiencing, particularly Kongwu’s attitude towards language, time, and self.

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