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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.
161

Moderní izraelská povídka / Modern Israeli Short Story

Maizels, Tereza January 2013 (has links)
The dissertation "Modern Israeli short story" focuses on the form of the current short prose studied on the work of four of the renowned Israeli contemporary authors. Employing the method of text comparison we try to illustrate the specifics of the modern Israeli short story. The dissertation contains both the theoretical overview as well as analytical material. The authors were selected according to several criteria: two male and two female writers which enables us to determine whether "gender" plays a role - meaning if each author favors heroes of a specific gender or if they focus only on "female" or "male" contents. We also chose two native Israeli writers and two authors of foreign descent that immigrated to Israel which enabled us to study the linguistic angle and to realize whether the writer's background is reflected in his/her work. The analytical parts as well as the amendments contain a number of samples which prove our conclusions.
162

Secure and Privacypreserving V2X multicast DNS

Atif, Ayub, Arieltan, Justin January 2020 (has links)
The Domain Name System is a hierarchical naming system that provides information of network resources or services given domain names. DNS applications in vehicular networks raise new challenges with regards to security and privacy of vehicles. In particular, vehicular communications outside the coverage of roadside infrastructure needs to be preserved. Multicast DNS is proposed as a method to restrict queries to vehicles in a Vehicle-to-Everything environment which could include other connected devices. Contemporary DNS applications rely on robust security protocols provided by the DNS Security Extensions to authenticate responses and verify resource records. Vehicular DNS communications need authentication to verify the source and legitimacy of DNS resource records. This can be achieved through multihop Vehicle- to-Vehicle communications to reach a name server supplemented by a novel approach to verify records using the Bloom filter.In this thesis, we analyze the security and privacy risks posed by a non-authenticated baseline communication protocol. We then build a secure and privacy-preserving networked system based on pseudonym certificate-based public key infrastructure solution. The experimental analysis confirmed the improvement on security and privacy at the cost of communication and computation overhead. / Domännamnssystemet är en hierarkisk benämningssystem som ger information om nätverksresurser eller tjänster för givna domännamn. DNS application i fordon nätverk framkallar nya utmaningar när det handlar om datasäkerhet och fordons integritet. Det är särskilt fordon kommunikation utanför vägkant-infrastrukturens räckvidd som behöver bevara och försäkra operationer av DNS applikation i fordon nätverk. Multicast DNS är en föreslagen metod för att begränsa förfrågan till fordon i en fordon-till-all-miljö som kan inkludera andra anslutna enheter. Nuvarande applikationer förlitar sig på en robust säkerhetsprotokoll som kommer från DNS säkerhetsförlängning för att autentisera svar och verifiera resurs rekord. Fordon DNS kommunikationer behöver autentisering för att verifiera källor och legitimitet av DNS resurs rekord. Detta kan uppnås genom multihop fordon-till-fordon kommunikation för att ansluta sig till en namn server med hjälp av en ny metod för att verifiera uppgifter med hjälp av bloomfilter datastruktur.I tesen analyserar vi risken som finns i en icke-autentiserad integritets-läckande kommunikationsprotokoll. Vi bygger sedan ett nätverk och använder en pseudonym certifikatbaserad publik nyckel infrastruktur lösning för att undersöka förbättringar inom säkerhet och integritet. Analysen från experimenten visar att det finns en förbättring för säkerhet och integritet i utbyte mot tidsprestanda, vilket är en intressant kompromiss.
163

Social and Asocial Niche Construction in Microbial Populations

Driscoll, William Wallace January 2012 (has links)
Cooperation presents a major challenge for evolutionary theory: how can competition favor a trait that imposes a cost on the individual expressing it while benefitting another? This challenge has been answered by theory that emphasizes the importance of assortment between individuals that tend to cooperate and those who tend to behave selfishly, or `cheat'. Microbial cooperation remains puzzling, given the generally high genetic and taxonomic diversity of most microbial communities. Many microbial populations rely on shared, beneficial extracellular products for an array of functions in nature. However, when these lineages are maintained in liquid cultures, many are invaded and outcompeted by spontaneous `cheater' mutants that forego investments in these products while benefitting from those produced by neighbors. The apparent evolutionary instability of microbial investments in extracellular products in well-mixed laboratory cultures finds a natural parallel in the phenomenon of toxic microalgal blooms. These extremely dense populations of often free-living microalgae destroy populations of competing microalgae and grazing zooplankton that normally control population densities. Bloom populations of planktonic microalgae are unstructured, and seem ill suited for the evolution of cooperation. In this thesis, I have established a new theoretical framework for understanding the evolution of microbial external goods. This framework highlights the importance of cell-level structure in the distribution of these external products, as well as genetic structuring in populations. This perspective informed an investigation into the social niche of a biofilm-dwelling regulatory mutant of the important biocontrol strain Pseudomonas chlororaphis. In the highly self-structured environment of a bacterial biofilm, a surprising mutualistic association between this mutant and the wild type emerged, underscoring the importance of microbial ecology in understanding the evolution of niche construction. Extending these lessons to the evolutionary problem of exotoxins in free-swimming microalgae yields the novel possibility that fluctuations in density of toxic strains shift a cell-level functioning exotoxin into a true public good that may be exploited by cheaters. I show that exotoxicity can serve cell-level functions in Prymnesium parvum. Despite these cell-level benefits, the existence of nontoxic lineages within toxic blooms hints at a complex interaction between rapid evolutionary and ecological changes in toxic blooms.
164

Synthesis of Water Quality Data and Modeling Non-Point Loading in Four Coastal B.C. Watersheds: Implications for Lake and Watershed Health and Management

Rodgers, Lisa 24 December 2015 (has links)
I compared and contrasted nitrogen and phosphorus concentrations and land use differences in two oligotrophic lakes (Sooke and Shawnigan) and two meso-eutrophic lakes (St. Mary and Elk) in order to evaluate nutrient concentrations over time, and evaluate the relationship between in-lake nutrients and land use in the surrounding watershed. I used MapShed© nutrient transport modeling software to estimate the mass load of phosphorus and nitrogen to each lake, and evaluated the feasibility of land use modifications for reducing in-lake nutrients. In comparing nitrogen and phosphorus data in Sooke and Shawnigan Lakes, I determined that natural watershed characteristics (i.e., precipitation, topography, and soils) did not account for the elevated nutrient concentrations in Shawnigan verses Sooke Lake. Natural watershed characteristics indicated that external loads into Shawnigan Lake would be lesser-than or equal to those into Sooke Lake if both watersheds were completely forested. I evaluated trends of in-lake nutrient concentrations for Sooke and Shawnigan Lakes, as well as two eutrophic lakes, St. Mary and Elk. Ten to 30-year trends indicate that nitrogen and phosphorus levels in these lakes have not changed significantly over time. Time-segmented data showed that nutrient trends are mostly in decline or are maintaining a steady-state. Most nutrient concentration data are not precipitation-dependent, and this, coupled with significant correlations to water temperature and dissolved oxygen, indicate that in-lake processes are the primary influence on lake nutrient concentrations -- not external loading. External loading was estimated using, MapShed©, a GIS-based watershed loading software program. Model validation results indicate that MapShed© could be used to determine the effect of external loading on lake water quality if accurate outflow volumes are available. Based on various land-cover scenarios, some reduction in external loading may be achieved through land-based restoration (e.g., reforestation), but the feasibility of restoration activities are limited by private property. Given that most of the causal loads were determined to be due to in-lake processes, land-based restoration may not be the most effective solution for reducing in-lake nitrogen and phosphorus concentrations. / Graduate
165

The Export of an Algal Toxin into Terrestrial Predators via Emerging Aquatic Insects

Moy, Nicholas J. 01 January 2015 (has links)
Algal blooms are directly related to human-caused nutrient enrichment of water bodies. The cyanobacteria Microcystis aeruginosa produces microcystin (MC), a toxin that has been linked with mortalities and illness of many organisms. We show that MC is not constrained by the aquatic-terrestrial ecotone. MC was detected in a primary consumer and emerging aquatic invertebrate (Hexagenia Mayfly), a terrestrial insect and predator of emerging aquatic invertebrates (Tetragnathidae Spider), and a vertebrate consumer (Prothonotary Warbler). Mayfly and spider MC levels varied across the blooming period. MC levels in prothonotary warbler livers varied by age class; nestlings having the highest levels. MC levels decreased in fledglings over time. A more aquatic diet was related to higher MC levels in nestlings at one site and nestling fecal-sacs varied spatially, also indicating that aquatic diet is related to MC consumption. Warbler body condition and growth rate was not related to liver microcystin levels.
166

Application of Fourier-transform infrared technology to the classification of harmful algal blooms (HABS)

Kenne, Gabriel Jacob January 1900 (has links)
Master of Public Health / Department of Diagnostic Medicine/Pathobiology / Deon Van der Merwe / Cyanobacteria are Gram-negative photosynthetic bacteria capable of producing toxins responsible for morbidity and mortality in humans and domestic animals. Many are capable of forming concentrated blooms that impact the environment by limiting the growth of sub-surface plants and phytoplankton. Harmful algal blooms (HABs) are also capable of producing multiple types of toxins, creating a potential hazard to recreational water users and animals drinking water from or near a bloom. Characterization of HABs is necessary to prevent these human and animal exposures and includes classifying of the type of cyanobacteria present and whether or not they are capable of toxin production, and the exact type of cyanotoxin that is actually present in bloom. Current methods used to classify cyanobacteria and cyanotoxins include microscopy, bioassays, ELISA, PCR, HPLC, and LC/MS. All of these methods, however, have limitations that include time, labor intensity, or cost. Fourier-Transform Infrared Spectroscopy (FTIR) is another potential tool for cyanobacterial classification that is not limited by these factors. To examine the practicality of this method, library screening with default software algorithms was performed on diagnostic samples received at the Kansas State University Veterinary Diagnostic Lab, followed by PCA of samples meeting minimum quality requirements to produce cluster analyses and dendrograms. Both spectrometers and software packages used were successful at distinguishing cyanobacteria from green algae in clean samples with 89.13% agreement. PCA resulted in clear classification of cyanobacteria or green algae demonstrated by a large order of magnitude difference produced by average Euclidian distance dendrograms. While this method is only capable of differentiating cyanobacteria from green algae or other aquatic environmental constituents, its simple, rapid use and low cost make it a beneficial screening tool when coupled with toxin-detection methods to characterize HABs.
167

Caracterização espectral das imagens de cor do oceano durante florações de fitoplâncton na Lagoa dos Patos / Spectral characterization of ocean color images during phytoplankton blooms at Lagoa dos Patos

Jorge, Daniel Schaffer Ferreira 07 October 2013 (has links)
A Lagoa dos Patos (LP) é um dos ambientes oticamente complexos mais bem estudados no Brasil, e sua grande abrangência espacial, permite a união de diferentes medidas in situ com produtos de sensoriamento remoto, sendo possível entender melhor como os componentes óticos da água influenciam na sua cor. Florações de fitoplâncton possuem grande relevância ecológica e econômica, sendo o desenvolvimento de metologias simples para o seu monitoramento de vital importância. O presente trabalho utilizou produtos de coloração do oceano de imagens diárias dos sensores MODIS/Aqua e SeaWiFS durante os anos de 2002-2005, dados de modelos meteorológicos de reanálise para precipitação e velocidade do vento e dados de clorofila-a e salinidade obtidos in situ. Foi identificado que o espectro de reflectância de sensoriamento remoto é controlado pelo regime de El Niño e La Niña, variação intra anual e espacial (p<0.05), sendo a cor da água da LP em geral, característica de ambientes com alta concentração de CDOM/sedimentos ou de domínio misto. Partindo do pressuposto que o fitoplâncton domina o coeficiente de absorção da luz durante florações de fitoplâncton, e que as possíveis florações na LP se restringem a diatomáceas e cianobactérias, foi desenvolvido um modelo de classificação para discriminar a ocorrência desses eventos. O modelo proposto permite a classificação de águas oticamente complexas de acordo com o componente ótico predominante, e é pioneiro na exploração de dados do sensor MODIS/Aqua para detecção de florações de fitoplâncton em um ambiente lagunar / Patos Lagoon (PL) is one of the optical complex environment best studied in Brazil, and it large spatial extent, allows the union of different in situ and remote sensing measures, enabling a better understandment of how the optical components in water can influence its color. Phytoplankton blooms have great ecological and economic relevance, and the development of simple methodologies for your monitoring of vital importance. The present work used ocean color products from daily MODIS/Aqua and SeaWiFS images during the years 2002-2005, meteorological model data for precipitation and wind speed and chlorophyll-a and sailinity data obtained in situ. It was detected that remote sensing reflectance spectra is controlled by the regime of El Niño and La Niña, intra annual and spatial changes (p<0.05), ande the water color from PL in general, characteristic of environments with high CDOM/sediments concentration or with mixed domain. Assuming that the phytoplankton dominate light absorption coefficient during phytoplankton blooms, and that PL possible blooms are restricted to diatom and cyanobacteria, a classification model was developed to discriminate the occurance of those events. The proposed model allows for the classification of optically complex waters according to the predominant optical component, and it is pioneer in the exploration of data from MODIS/Aqua sensor to detect phytoplankton blooms in lagunar environment
168

A qualitative study of six applied music teachers within the context of Bloom's second phase of talent development

Sergey, Thomas Michael 13 March 2017 (has links)
Attrition rates among applied music students accelerate as young people progress through adolescence. Once disengaged from music participation in the teenage years, disinterest tends to persist throughout adulthood. The aim of this qualitative study was to investigate the teaching practices of applied music teachers as they worked with teenagers at a talent development level referred to as second phase (Bloom, 1985), which is typically reached in adolescence. The study investigated teaching and learning behaviors in the lessons, teachers’ management of para-instructional decisions (such as monitoring students’ progress and recommending students for collegiate-level study), and teachers’ strategies for influencing, motivating, and nurturing students. Purposeful sampling was used to recruit six classical guitar, harp, and piano teachers. Data collected from music lesson observations, semi-structured interviews, and documents were analyzed typologically for occurrences of predetermined categories of instructional behaviors and inductively for emergent themes. The study revealed several findings. Verbal directives and questions, positive approbations, and playing models dominated the teachers’ behavior. The teachers accommodated individual learning styles and empowered their students by providing them with decision-making opportunities. The teachers’ pedagogies were systematic and goal driven, with refined tone and strategies for lifelong music making among the pedagogical foci. Musical analysis was integral to the teaching, as it served to deepen students’ intellectual understanding of the music and support their memorization during performances. The teachers prescribed exact practice routines, which most of them provided in written form. The findings suggest that in light of the voluntary nature of applied music study in adolescence and the many activities competing for students’ time, a chief concern of the teachers was to influence and motivate their students to continue their participation in music lessons. The teachers accomplished this by utilizing six categories of teaching strategies, some of which could involve decisions contrary to their own musical preferences and pedagogical inclinations. The strategies’ synergy maximized the facilitation of positive student experiences, particularly those associated with public performance. These experiences seemed to fulfill students’ drive for independence, satisfy their need for recognition, and boosted their motivation to work towards achieving higher proficiency levels. / 2024-03-31T00:00:00Z
169

Avaliação da hierarquização na remoção de cianotoxinas por meio da adsorção em carvão ativado granular

Silva, Maria Natália Costa e 26 August 2014 (has links)
Submitted by Jean Medeiros (jeanletras@uepb.edu.br) on 2016-03-10T13:44:20Z No. of bitstreams: 1 PDF - Maria Natália Costa e Silva.pdf: 1280209 bytes, checksum: df5d2a51e71f30434a166906afcbecd3 (MD5) / Made available in DSpace on 2016-03-10T13:44:20Z (GMT). No. of bitstreams: 1 PDF - Maria Natália Costa e Silva.pdf: 1280209 bytes, checksum: df5d2a51e71f30434a166906afcbecd3 (MD5) Previous issue date: 2014-08-26 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The greater input of nutrients, such as nitrogen and phosphorus, from various anthropogenic uses of watersheds is one of the causes of the high growth rate of algae and cyanobacteria. Algae bloom impacts the quality of water causing taste and odor problems due to chemicals and toxins, called cyanotoxins, produced by these microorganisms. This situation, observed in sources of water supply, is worrying since the conventional treatment used by 70% of the water treatment stations in Brazil are not able to effectively remove those toxins. Studies performed by research groups around Brazil have shown the coexistence of two cyanobacteria, Microcystis aeruginosa and Cylindrospermopsis raciborskii, producers of the cyanotoxins microcystin and saxitoxins, respectively, which justifies the study of the removal of these toxins concomitantly. The aim of this study was to evaluate the ranking in removing microcystin-LR and saxitoxins-STX by adsorption on granular activated carbon (GAC) from different sources and particle sizes. Two types of palm coconut shell charcoal with the following mesh sizes 8x30 (FDG) and 12x40 (FDF) were used. A mineral charcoal with a 12x25mesh (FCM) was also used. The adsorption was made by filtration columns. The cyanotoxins were extracted from cultures of pure strains of M. aeruginosa and C. raciborskii. The method used for quantification was the immunoassay ELISA. First, we analyzed the removal efficiencies of MC-LR with each type of charcoal using samples of treated and distilled water. The filters were operated at a 66.3 m 3 /m 2 .d filtration rate. The results of this first phase showed a more effective removal of FDF (67.3%), although the average removal of FCM was higher (72.3%). In the second phase of the study, we analyzed the concomitant removal of MC-LR and STX using FDF at a 35.1 m 3 /m 2 .d filtration rate. The average removals of 58.9% and 92.5%, respectively, showed that the removal of saxitoxins is better, although we cannot assume that this toxin excels in the ranking. As for the difference between the filtration rates, we found that the removal is better with filters operating at a lower rate. / O aporte maior de nutrientes como nitrogênio e fósforo provenientes dos diversos usos antrópicos das bacias hidrográficas é um dos responsáveis pela alta taxa de crescimento de algas e cianobactérias. O bloom desses microrganismos modifica a qualidade da água, produzindo substâncias que conferem gosto e odor à água e até mesmo substâncias tóxicas, como as cianotoxinas. Essa situação presente nos mananciais de abastecimento é preocupante uma vez que o tratamento convencional utilizado por 70% das estações de tratamento de água no Brasil não são efetivamente capazes de remover tais substâncias tóxicas. O registro por grupos de pesquisa em todo país da presença conjunta de cianobactérias como a Microcystis aeruginosa e Cylindrospermopsis raciborskii, potencialmente produtoras das cianotoxinas microcistinas e saxitoxinas, respectivamente, justifica o estudo da remoção dessas toxinas em concomitância. O carvão ativado granular (CAG) é a tecnologia de tratamento avançado utilizada nesse trabalho que objetiva avaliar a hierarquização da remoção de microcistina-LR e saxitoxina STX por meio da adsorção em CAG de natureza e granulometrias distintas. Foram utilizadas colunas de filtração com dois carvões de casca de coco de dendê com granulometrias 8x30mesh (FDG) e 12x40mesh (FDF) e um carvão mineral com granulometria 12x25mesh (FCM). As cianotoxinas foram extraídas de cultivos de cepas puras de M. aeruginosa e C. raciborakii potencialmente produtoras e foi utilizado o método por imunoensaio ELISA para quantificação. Primeiramente foram analisadas as eficiências de remoção de MC-LR em cada tipo de carvão com águas de estudo formadas por água tratada e água destilada. Os filtros foram operados com taxa de filtração 66,3m³/m².d e os resultados dessa etapa evidenciaram remoção mais efetiva para o FDF (67,3%) apesar de a remoção média do FCM (72,3%) ter sido maior. Na segunda etapa do trabalho foi analisada a remoção em concomitância de MC-LR e STX e utilizou-se o FDF a uma taxa de 35,1m³/m².d em que as médias de remoção de 58,9% e 92,5%, respectivamente, evidenciaram que a saxitoxina apresenta melhor remoção, mas não se pode assumir que sobressai nessa hierarquia. Quanto à diferença nas taxas de filtração aplicadas, encontrou-se melhor remoção nos filtros operados com menor taxa.
170

Developing Ocean Color Algorithm using Moderate Resolution Imaging Spectroradiometer (MODIS) Sensor for Shallow Coastal Water Bodies

Abbas, Mohd Manzar 20 June 2018 (has links)
This study analyses the spatial and temporal variability of chlorophyll-a in Chesapeake Bay; assesses the performance of Ocean Color 3M (OC3M) algorithm; and develops a novel algorithm to estimate chlorophyll-a for coastal shallow water. The OC3M algorithm yields an accurate estimate of chlorophyll-a concentration for deep ocean water (RMSE=0.016), but it failed to perform well in the coastal water system (RMSE=23.17) of Chesapeake Bay. A novel algorithm was developed which utilizes green and red bands of the Moderate Resolution Imaging Spectroradiometer (MODIS) sensor. The novel algorithm derived the chlorophyll-a concentration more accurately in Chesapeake Bay (RMSE=4.20) than the OC3M algorithm. The study indicated that the algorithm that uses red bands could improve the satellite estimation of chlorophyll-a in the coastal water system by reducing the noise associated with bottom reflectance and colored dissolved organic matter (CDOM)

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