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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.
411

Stable Isotope Biogeochemistry of South Florida Coastal Marine Ecosystems

Strand, Sarah Elise 12 November 2014 (has links)
Southeast Florida’s continual urban expansion will potentially increase anthropogenic pollution in adjacent coastal marine systems. Furthermore, increased nutrient loads could have detrimental effects on the already threatened Florida Reef Tract. The present study uses a stable isotopic approach to determine the sources and the impact of nutrients on the Florida Reef Tract. δ13C and δ15N analysis of macroalgae, sponges, and sediment were analyzed in order to determine nutrient inputs in this region. While δ13C data did not display any significant trends spatially, δ15N values of the majority of biota exhibited a strong East to West gradient with more enriched values close to shore. Relative enrichment in δ15N values were measured for sediments sampled along the Florida Reef Tract in comparison to a pristine Marquesas Keys sediment core. The δ15N data also implies that shoreline anthropogenic nutrients have more nutrient loading implications on reefs than major point sources.
412

A framework for the assessment of nursing tasks and environmental demands

Durosaiye, Isaiah Oluremi January 2017 (has links)
The nursing profession is pivotal to the delivery of healthcare services within the UK National Health Service (NHS). However, studies have shown that an increasing number of older nurses are leaving the NHS as a result of the physical and cognitive demands of the nursing job. In particular, a growing body of literature suggests that ward nurses are at risk of sustaining work-related injuries due to the demands of their job. Responding to these challenges, the aim of this PhD research project was to develop a framework to support NHS ward nurses in the ward environment, by exploring how the architectural design features of NHS hospital wards could be improved to create a better fit between ward nurses and their work environment, by applying the Person-Environment Fit theory. The Nursing Tasks and Environmental Assessment Framework (NTEA Framework) consists of two components. The Nursing Tasks Demand Matrix (NTDM), which provides a nuanced understanding of nursing tasks on wards and the Ward Environment Assessment Tool (WEAT), which is used to conduct Post-Occupancy Evaluation of hospital wards. The two together forms the NTEA Framework, which offers a holistic approach to improving nurses’ quality of life in the workplace. The NTEA Framework may be used by facilities managers, human resource managers, occupational health advisors, ward managers and the NHS management, for refurbishments decisions, in drafting nurses’ job descriptions, to perform occupation health screening and for the assessment of the adequacy of NHS healthcare estates for ward nurses. The NTEA Framework is also a benchmarking information tool that could inform design of healthcare facilities.
413

Elementos químicos em invertebrados terrestres como indicadores de qualidade ambiental de áreas urbanas

SANTOS, Mariana Luiza de Oliveira 26 February 2016 (has links)
Submitted by Fabio Sobreira Campos da Costa (fabio.sobreira@ufpe.br) on 2017-07-14T13:25:17Z No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) Dissertacao com as correcoes da banca-2.pdf: 7763298 bytes, checksum: 36272e73c79d4926dc5e8ecb3b84eb35 (MD5) / Made available in DSpace on 2017-07-14T13:25:17Z (GMT). No. of bitstreams: 2 license_rdf: 811 bytes, checksum: e39d27027a6cc9cb039ad269a5db8e34 (MD5) Dissertacao com as correcoes da banca-2.pdf: 7763298 bytes, checksum: 36272e73c79d4926dc5e8ecb3b84eb35 (MD5) Previous issue date: 2016-02-26 / FACEPE / Invertebrados terrestres podem ser empregados como biomonitores para a avaliação da qualidade ambiental de áreas urbanas devido à capacidade de absorver substâncias químicas do ambiente por meio da alimentação ou contato direto. Ainda são poucos os estudos realizados utilizando insetos como biomonitores, mesmo sendo bastante relevantes ao considerar seu papel ecológico e densidade populacional elevada. Este trabalho foi realizado com o intuito de utilizar invertebrados terrestres como biomonitores nas áreas urbanas Manguezal Memorial Arcoverde, Reserva da Mata do Frio e Campus Tecnológico do Nordeste, todas localizadas em Pernambuco. Para fins de monitoração de impactos ambientais, foram utilizados padrões de referência para estudos ambientais da classe Insecta obtidos no Refúgio Ecológico Charles Darwin, Igarassu, Pernambuco, unidade conservação com maior grau de conservação. A coleta dos invertebrados para realização do estudo foi executada utilizando-se armadilhas com iscas de mel, laranja, sardinha e carne putrefata a fim de atrair animais com diferentes hábitos alimentares. Após a coleta, os invertebrados foram lavados e em seguida, separados em nível de ordem para realização das análises químicas. A maior diversidade de ordens de invertebrados terrestres foi encontrada na Reserva da Mata do Frio, enquanto a ordem mais abundante coletada nas áreas urbanas estudadas foi Hymenoptera. Porções-teste de 0,1 g de massa seca foram analisadas por Espectrometria de Fluorescência de Raios-X por Dispersão de Energia (EDXRF), Espectrometria de Massas com Plasma Indutivamente Acoplado (ICP-MS) e Absorção Atômica por Forno de Grafite (GFAAS). A qualidade do procedimento analítico foi avaliada utilizando-se de porções-teste dos materiais de referência SRM 2976, SRM 8414, SRM 8415 e IAEA 336. As técnicas analíticas empregadas permitiram a determinação da concentração dos elementos químicos As, Cd, Cl, Co, Cr, Cu, Fe, K, Mo, P, Pb, S, Sb, Th, U e Zn nos invertebrados das áreas urbanas estudadas. O manguezal Parque Memorial Arcoverde apresentou maiores características de ambiente impactado, devido às elevadas concentrações de Cd, Co, Cu, Mo, S, Sb e Zn nos invertebrados analisados. Na Reserva da Mata do Frio, foram obtidas concentrações superiores dos elementos químicos Cl, Cu, K e Zn, enquanto que, no Campus Tecnológico do Nordeste, o elemento químico Cd se destacou por apresentar concentração superior a faixa esperada em amostras de Hymenoptera. Considerando a relativa facilidade de coleta e análise, diversos ecossistemas puderam ser avaliados convenientemente utilizando invertebrados terrestres. / Terrestrial invertebrates can be employed as biomonitors for the environmental quality assessment in urban areas due to the ability of uptake of chemical substances through food or direct contact. Moreover, there are few studies using insects as biomonitors, even though their relevance owing to their ecological role and high population density. This work has utilized terrestrial invertebrates as biomonitors in the urban areas Parque Memorial Arcoverde, Reserva da Mata do Frio and Campus Tecnológico do Nordeste, located in the Pernambuco State, Brazil. Reference standards for environmental studies of class Insecta obtained in the Refúgio Ecológico Charles Darwin, Igarassu, Pernambuco, Brazil, a conservation unit of high conservation level, were used for environmental impact monitoring purposes. Invertebrates were sampled by using traps with honey, orange, sardine and rotten meat as attractive for animals of different food habits. After, the invertebrates were washed and then separated at the order level in order to analyze the chemical elements. The greatest diversity of orders was found in the Reserva da Mata do Frio, while the most abundant order in the studied urban areas was Hymenoptera. Test portions of 0.1 g were analyzed by Energy Dispersive X-Ray Fluorescence Spectroscopy (EDXRF), Inductively Coupled Plasma Mass Spectrometry (ICPMS) and Graphite Furnace Atomic Absorption (GFAAS). The quality of the analytical procedure was evaluated using the reference materials SRM 2976, SRM 8414, 8415 and IAEA 336. The analytical techniques employed here allowed the determination of As, Cd, Cl, Co, Cr, Cu, Fe, K, Mo, P, Pb, S, Sb, Th, U and Zn in the invertebrates from the studied urban areas. The Parque Memorial Arcoverde mangrove was considered one of the most impacted areas according to the high concentrations of Co, Cu, Mo, S, Sb and Zn determined in the invertebrates. For the Reserva Mata do Frio, it was observed the highest concentrations of the chemical elements Cl, Cu, K and Zn, while one invertebrate sample from the Campus Tecnológico do Nordeste accumulated Cd above the expected range. Considering the relative facility of sampling and analysis, diverse ecosystems could be appropriately assessed by means of terrestrial invertebrates.
414

Avaliação do impacto da contaminação do solo de áreas agrícolas de Bom Repouso (MG) por meio de ensaios ecotoxicológicos / Assessment of the contamination impact of the soil in agricultural areas from Bom Repouso (MG) by ecotoxicological tests

Natália Costa de Lima 01 October 2010 (has links)
Nas últimas décadas tem-se verificado um significativo aumento na quantidade de contaminantes que são liberados no ambiente, destacando-se os agrotóxicos como um dos mais utilizados e nocivos. Os agrotóxicos são utilizados para o controle de doenças, pragas e plantas invasoras e, apesar de sua eficiência, seus efeitos em nível de ecossistema e saúde humana são preocupantes. No município de Bom Repouso/MG, devido à prática agrícola há intenso uso de agrotóxicos, os quais são aplicados nas lavouras de morango e batata sem controle mais efetivo, não sendo verificada nenhuma avaliação ambiental física, química e biológica, ou que incluísse os testes de toxicidade terrestres. Dentro desse contexto, o presente estudo procurou avaliar a aplicabilidade dos testes ecotoxicológicos padronizados internacionalmente para organismos terrestres, além de avaliar os impactos ambientais decorrentes das atividades agrícolas no município de Bom Repouso. Para tanto, ensaios de toxicidade (testes de evitamento, toxicidade aguda e crônica) com a espécie Eisenia andrei (ANNELIDA, OLIGOCHAETA), além de análises físicas e químicas, foram realizados com amostras de solo coletadas nas monoculturas de morango e batata, e em área de mata preservada. Nas análises físicas e químicas dos solos foram detectadas concentrações de metais e agrotóxicos em concentrações abaixo de valores orientadores definidos em legislação vigente, ressaltando-se que ambos também ocorreram em áreas de mata preservada. Elevadas concentrações de alumínio foram detectadas nos solos, porém não existem valores orientadores estabelecidos e provavelmente são características do tipo de solo da área de estudo. Não foi verificada toxicidade aguda aos organismos-teste, enquanto que nos testes de evitamento verificou-se que os organismos evitaram os solos de área de cultivo de morango e batata, preferindo os da mata; porém não é possível afirmar se esse resultado se deve à presença de contaminantes ou às propriedades físicas e químicas dos solos. Em relação aos efeitos subletais, a perda de peso não foi caracterizada como efeito de toxicidade, e os efeitos sobre a reprodução, para a maioria dos solos testados, não foram significativos, com exceção de duas amostras coletadas em área de mata e uma amostra de área de batata. Este resultado pode ter sido influenciado pelas concentrações de agrotóxicos não detectados (mas identificados em estudos anteriores), embora as características ácidas do solo também possam ter maior representatividade. Especificamente para as áreas de mata, as concentrações de alumínio detectadas nos solos e a dificuldade de ajuste de umidade provavelmente também influenciaram os resultados. Em função dos resultados obtidos, verifica-se que ainda são necessárias alterações nos procedimentos dos testes ecotoxicológicos com organismos terrestres, com adaptações para testes com amostras de solos naturais. Em relação ao município de Bom Repouso, são evidentes os problemas ambientais decorrentes do uso de agrotóxicos, sendo necessária uma avaliação de risco que permita uma visão sistêmica da situação ambiental e de saúde dos moradores da região. / In the last decades there has been a significant increase in the amount of contaminants that are released into the environment, especially pesticides as one of the most used and harmful. The pesticides are used to control diseases, plagues and invaded plants and, despite its efficiency, its effects on the ecosystem level and human health are disturbing. In the Bom Repouso/MG municipality, due to the agricultural practice, there is an intensive use of pesticides, which are applied in strawberry and potato crops without more effective control, and it is not checked any biological, chemical and physical environmental assessment, which would include tests for terrestrial toxicity. In this context, this current study sought to evaluate the applicability of ecotoxicological tests internacionally standardized for terrestrial organisms and to evaluate the environmental impacts of agricultural activities in the Bom Repouso/MG municipality. Therefore, toxicity tests (tests of avoidance, chronic and acute toxicity) with the species Eisenia andrei (ANNELIDA, OLIGOCHAETA), in addition physical and chemical analysis, were performed with soil samples collected from monocultures of strawberry and potato, in addition preserved forest. In the chemical and physical analysis of the soils were detected concentrations of metals and pesticides in concentrations below the guiding values defined in current legislation, emphasizing that both also occurred in areas of preserved forest. High concentrations of aluminum were detected in soils, but there are no established guinding values and probably these are characteristics of the soil type of the study area. It was not observed acute toxicity to the test-organisms, whereas in tests of avoidance, it was observed that the organisms avoided the soils of the cultivation of strawberry and potato, preferring the forest, but it is not possible to state whether this result is due to the presence of contaminants or the chemical and physical properties of the soils. With respect to the sub lethal effects, the weight loss was not characterized as an effect of toxicity, and the effects on reproduction, for the most soils tested, were not significant, except for the two samples collected in the forest area and one sample in the potato area. This result may have been influenced by the concentrations of pesticides not detected (but identified in previous studies), although the acid soil characteristics may also have greater representation. Specifically for the forest areas, the concentration of aluminum detected in soils and the difficulty of the moisture adjusting, probably also influenced the results. Depending on the results, it observes that are still necessary changes in the procedures ecotoxicological tests with terrestrial organisms, with adjustments for tests with samples of natural soils. With reference to the Bom Repouso municipality, are obvious the environmental problems and because of the use of pesticides, it is necessary an assessment risk that allows a systemic view of the environmental situation and of the health of region residents.
415

Trends in Human-wildlife Interactions as Related to Land Use and Human Density in Massachusetts

Huguenin, Michael A, Jr 18 March 2015 (has links)
We conducted a study of human-wildlife interactions in Massachusetts, USA between April 2010 and May 2012. Our objectives were to (1) compile and summarize public-generated reports on human-wildlife interactions across Massachusetts; (2) evaluate reports based on species, public concerns, and seasonal distribution; and (3) evaluate public perceptions of human-wildlife interactions. We collected unsolicited reports of human-wildlife interaction submitted to the Massachusetts Division of Fisheries and Wildlife (MDFW) through phone calls, emails, and face-to-face communications from the public. We received 2,730 reports from 332 of 351 towns in Massachusetts regarding 76 different wildlife species ranging from moose (Alces alces) to honey bees (Apis mellifera). Coyotes (Canis latrans) (328, 12%), bears (Ursus americanus) (307, 11%), and foxes (Vulpes vulpes and Urocyon cinereoargenteus) (284, 10%) were the most common species reported. Property disturbance/damage was the most common report type (934, 35%), concern for the welfare of wildlife was the most common concern type (539, 24%), and the most common report and concern pairing (referred to as perception type) was reports of young/injured wildlife with a concern for the welfare of wildlife (279, 13%). We tested for differences in reporting rates of human-wildlife interactions among seasons (spring, summer, fall, and winter) and among 5 urban-suburban development categories (low, medium-low, medium, medium-high, high). The distribution of total animal report records were greater than expected for spring and for summer and less than expected for fall and for winter. The distribution of total animal report records were less than expected for low and medium-low development categories, and greater than expected for medium, medium-high, and high development categories. We then conducted multiple regression analyses to examine how total reports of human-wildlife interactions, as well as reports of human and species-specific interactions (coyotes, foxes, bears, fishers (Martes pennanti), and birds of prey) related to median home value and landscape composition and configuration. Total reports and reports of coyote, fox, and fisher were correlated with our model.
416

Modeling Historical and Future Range of Variability Scenarios in the Yuba River Watershed, Tahoe National Forest, California

Mallek, Maritza 13 July 2016 (has links)
In California's northern Sierra Nevada mountains, the fire-dependent processes of forest ecosystems have been interrupted and altered by human land use and fire suppression. U.S. Forest Service policy directs land managers to plan for a future that includes multiple use and the restoration of resilient ecosystems. Planning decisions are to be informed by an analysis of the range of variability of ecological processes at multiple scales. Current climate trends in the northern Sierra are of increasing temperatures, increased precipitation, and earlier snowmelt, as well as changes to the frequency and duration of drought. These climate changes have and continue to influence fire frequency, extent, and severity. For this thesis, project partners and I adapted the Rocky Mountain Landscape Simulator (RMLands), a spatially explicit, stochastic, landscape disturbance and succession model, for use in the Sierra Nevada. RMLands was used to simulate wildfires and vegetation dynamics on a portion of the Tahoe National Forest in California, first under historical climate settings and then under alternative climate trajectories based on the Representative Concentration Pathway RCP8.5 projections. I then quantified the historical and the future ranges of variability in the disturbance regime, seral stage distribution, and patch configuration, and compared these to the current landscape. My results suggest more frequent and extensive high severity fire, as well as higher canopy closure, than most other studies of mixed conifer Sierran forests. However, the results typically agree qualitatively with other research, and some differences may be due to differences in study design. Under warmer and drier future climate scenarios, the total area burned, and the proportion burned at high severity, increased. Due to fire's effects on vegetation, the current landscape departs from either historical or future conditions by several statistical measures. Based on these findings, I recommend that managers implement aggressive restoration efforts, utilize mitigation measures where the consequences of changing fire regimes are socially unacceptable, and carefully balance the needs of different ecosystems and of the resident communities. My study can be used to inform goals and specific strategies in restoration planning and help project planners think about impacts at the landscape scale.
417

Improving Growth and Survival of Cultured Yellow Lampmussel (Lampsilis cariosa) for Restoring Populations

Martell, Virginia 01 February 2020 (has links)
In North America 72% of freshwater mussel species are endangered, threatened, or of special concern due to factors such as habitat loss and degradation, biological invasion, and land use change. Propagation of freshwater mussels has been considered a necessary conservation strategy for population restoration where threats have been mitigated but small population sizes limit population viability. Yellow lampmussel is a species of freshwater mussel that is endangered, threatened, or imperiled throughout its range; therefore, I evaluated laboratory techniques (probiotic supplements and secondary rearing designs) to improve culture of yellow lampmussel for population restoration. Several aquaculture facilities commonly use probiotics; thus, I used commercial probiotics to determine if 1) probiotic concentration and 2) type of probiotic mixture improved growth or survival of juvenile mussels during primary culture. I further asked whether probiotics affected mussels by reducing ammonia, thereby improving water quality. Some probiotics increased survival (and, in one experiment, increased growth) of juvenile mussels, regardless of concentration, but results were variable by experiment and probiotic type. Probiotics did not significantly reduce ammonia concentrations, so this was unlikely the mechanism of benefit. I also investigated the effect of different secondary rearing systems at two culture facilities on growth and survival of juvenile mussels in two size classes (5.0 mm). I used five different secondary culture systems that were either indoors (dogpans and baskets) or outdoors (trough, airlift upweller, tank upweller, baskets), where water was either recirculating or flow-through. Survival was exceptional in all larger size class rearing systems, and the baskets in the ponds had the greatest growth rates. Smaller mussels had lower survival than the larger mussels, indicating that when deploying juvenile mussels into outdoor culture systems mussels size should be greater than 5.0 mm. Results of this project will inform future rearing yellow lampmussel in New England and more broadly add to the limited literature on probiotic use and secondary rearing designs in freshwater mussel culture.
418

Hydrologic Controls on Phosphorus Speciation and Mobilization in a Subalpine Watershed (East River, Colorado)

Arthen-Long, Lucia Isobel 20 October 2021 (has links)
The cycling of phosphorus (P) through floodplain environments is critical to ecosystem productivity and has significant implications on both water quality and soil fertility. P export from soils in response to saturation has been well documented, but the relative vulnerability of specific P pools to mobilization remains poorly constrained, as do the mechanisms mediating its release. The prediction of P availability in and export from mountainous floodplain soils is of great importance as global climate change is projected to significantly alter precipitation regimes in alpine systems. This study combined a thorough characterization of P distribution across a hillslope to floodplain transect with a high resolution analysis of P response to saturation, providing insight into both P cycling and flood-induced mobilization in the East River watershed in Gothic, Colorado. P-XANES, 31P NMR, and sequential extractions revealed that P concentrations were greatest in the floodplain and dominated by inorganic P (Pi) bound to primary minerals, while hillslope P was lower and characterized by more bioavailable and organic (Po) pools. Time series analysis of P response to extended water saturation confirmed our hypothesis that P mobilization would occur in two phases, first driven by lysis of microbial cells upon initial rewetting, and later driven by the reductive dissolution of Fe oxides with extended saturation. These findings indicated that (i) the interaction of weathering and hydrology dictate P speciation across the transect; (ii) hillslope P may be concentrated in microbial pools while floodplain P is primarily bound by minerals; (iii) bioavailable P pools may be dominated by Po; and (iv) Po is more vulnerable to mobilization during initial rewetting of dried soils while Pi responds more to changes in redox potential during extended saturation. Results from this study underscore the significance of hydrology in determining P speciation and mobilization, indicating that long-term changes in precipitation may influence P bioavailability and export from alpine watersheds. Understanding the mechanisms by which P is mobilized is therefore of critical importance to better predict soil P response to saturation in a changing climate.
419

Postup digitalizace v Česku a na Slovensku na příkladu sportovních kanálů ČT4 Sport a Trojky / Progress in digitizing of television broadcasting in Czech and Slovak Republic at the example of sport channels ČT4 Sport and Trojka

Kalemba, Jiří January 2009 (has links)
Diploma thesis "Progress in digitizing of television broadcasting in Czech and Slovak Republic at the example of ČT4 Sport and Trojka" deals with contemporary status of analogue to digital broadcasting changeover. Its goal is to explore and compare this difficult process in two countries - Czech and Slovak Republic. For detailed results of this comparison there will also be analysis of two digital sport channels - ČT4 Sport and Trojka - in my diploma thesis. Both channels belong to public broadcasters. This diploma thesis intends to notice, describe and explain all differences found throughout the analysis.
420

Dokumentace části hradu Rokštejn pomocí laserového skenování / Documentation of Rokštejn using laser scanning

Schwarz, Jakub January 2016 (has links)
The aim of this thesis is the measure of the Rokštejn castle by laser scanning. The measured data are processed in the SCENE software and accuracy of registration and transformation of scans is intended. The next step is to test the software for working with point cloud. In the end, is in the selected 3D software created 3D model of the castle by using processed point cloud.

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