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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.
51

Avaliação da eficácia de medidas de recuperação ambiental em mineração de calcário para cimento. / Assessment of effectiveness rehabilitation measures in limestone mines.

Ana Claudia Neri 12 November 2007 (has links)
A gestão do processo de recuperação de uma área degradada pela mineração consiste em três etapas principais: planejamento; implementação das medidas de correção ou prevenção e implementação de gestão. Neste trabalho, foi desenvolvido um instrumento de avaliação que pode ser usado por órgãos públicos ou por empresas de mineração para auxiliar no controle e melhoria das práticas de recuperação ambiental. A avaliação é feita por meio da aplicação de um roteiro, fundamentado nas boas práticas internacionais e nacionais relacionadas à recuperação ambiental de minas. Para fins de teste e calibração, os roteiros foram aplicados em três minas de calcário, nas quais se verificou que as evidências - visuais, documentais e verbais (obtidas por meio de entrevistas) - coletadas devem ser interpretadas dentro de um contexto que envolva o entendimento das características ambientais e operacionais particulares de cada mina. As categorias de classificação da avaliação da eficácia de medidas de recuperação ambiental foram definidas em: eficaz, parcialmente eficaz, não eficaz e não se aplica. Ante aos resultados, foi possível identificar um \"cenário atual\" das práticas de recuperação ambiental empregadas em cada mina inspecionada e consequentemente recomendar ações visando a melhoria das práticas atuais e a redução de um futuro passivo ambiental. Diante destes resultados, conclui-se que o procedimento de avaliação da eficácia de medidas de recuperação ambiental desenvolvido nesta pesquisa é adequado, mas sua aplicação somente pode ser feita por um profissional que detenha alguma experiência no assunto, fator primordial para o julgamento e contextualização das evidências coletadas. O roteiro proposto nesta pesquisa ainda pode ser aplicado em outras minas de diferentes minerais e pedreiras. / The reclamation process management of an area degraded by mining activity consists of three main steps: planning. application of correction or prevention measures and monitoring. In this work, an assessment tool to be used by public bodies or by mining companies in order to support the control and improvement of environmental reclamation practices was developed. The assessment has been carried out with a script based on the national and international good practices regarding environmental reclamation in mines. For testing and calibration purposes, the scripts were applied in three limestone mines. The conclusion is that the evidences - visual, documental and verbal (interview) - must be analyzed in a context which involves the understanding of the environmental and operational characteristics in each mine. The categories for classification of the efficacy assessment of environmental reclamation measures have been defined as: efficacious, partially efficacious, non-efficacious and not applicable. Considering the results, it was possible to identify a \"current scenario\" of the environmental reclamation practices used in each inspected mine and consequently recommend actions to improve the current practices and reduce a future environmental liability. It was concluded that the procedure of the efficacy assessment of the environmental reclamation practices developed in this research is appropriate, but its application can only be made by a professional that presents some experience in the subject. It is a decisive factor for the evaluation and contextualization of the collected evidences. The proposed script for this research can still be applied in other mines with different minerals and quarries.
52

Hidrossemeadura com espécies arbustivo-arbóreas nativas para preenchimento de áreas degradadas na Serra do Mar / Hydroseeding of native tree species to recover degraded areas on the Serra do mar

Fabiana de Arantes Basso 19 June 2008 (has links)
A técnica da hidrossemeadura é comumente empregada como medida de recuperação de taludes gerados nos empreendimentos rodoviários, áreas degradadas pela mineração, aeroportos e hidrelétricas, utilizando gramíneas agressivas e leguminosas visando um rápido recobrimento do solo para conter a erosão. O uso de espécies arbustivo-arbóreas nativas na hidrossemeadura ainda é pouco estudado, destacando-se alguns trabalhos de desenvolvimento de equipamentos e escolha de espécies adequadas. Inserido neste contexto a proposta do trabalho foi testar a viabilidade da técnica da hidrossemeadura com espécies arbustivo-arbóreas nativas para preenchimento de áreas degradadas inseridas em uma matriz ainda com grande cobertura florestal remanescente, possibilitando o uso de uma baixa diversidade de espécies na hidrossemeadura, uma vez que o enriquecimento ocorreria naturalmente, com propágulos oriundos do entorno, se a condição do ambiente permitir a fixação desses propágulos. Para isto foram aplicados 14,88 kg de sementes em 2,64 ha de área, sendo 2,976 kg de cada uma das seguintes espécies arbustivo-arbóreas: Cecropia pachystachya, Mimosa bimucronata, Peltophorum dubium, Schinus terebinthifolius e Senna multijuga. O delineamento experimental foi o de blocos ao acaso em esquema fatorial 2x5 com um tratamento adicional e com quatro repetições de cada bloco. Foram testadas cinco doses diferentes de sementes (Kg/ ha) e a influência do adubo químico (NPK) no momento da aplicação da hidrossemeadura no preenchimento da área. A dissertação foi dividida em dois capítulos, o primeiro referente à viabilidade da técnica da hidrossemeadura, tendo o segundo avaliado o sucesso de estabelecimento das espécies utilizadas. De maneira geral a técnica da hidrossemeadura apresentou-se viável para preenchimento das áreas, porém, estudos com espécies arbustivo-arbóreas são necessários para indicação das espécies mais adequadas. / Hydroseeding is a common practice on the restoration of slopes generated by road, airport and hydroelectric constructions or mining activities, and its usually applied with fast-growing grasses and legumes, aiming rapid soil recovery and erosion control. Hydroseeding of native tree species is scarce, except for few studies on equipment development and selection of adequate species. Within this context, this study aims to test the feasibility of native tree species on hydroseeding as a technique to recover degraded areas within a landscape where prevails forest remnants, which allows a low diversity on hydroseeding, once the enrichment of species may occur naturally through incoming propagules from forested neighbourhood. The native tree species evaluated by this study were: Cecropia pachystachya, Mimosa bimucronata, Peltophorum dubium, Schinus terebinthifolius and Senna multijuga. Five different quantities of seeds (Kg/ ha) and the influence of chemical manure (NPK) during application were tested. It was a 2x5 factorial experiment folowing the randomized block design and with an additional control treatment (without hydroseeding nor chemical manure). Dissertation is presented on two chapters: the first one refers to the native tree species´ hydroseeding feasibility and the second evaluates the establishment success of these species. As an overall conclusion hydroseeding is feasible and effective to recover degraded areas, although further studies are needed to indicate the most suitable native tree species for this technique.
53

DiagnÃstico da ocorrÃncia de micro-organismos simbiontes em Ãreas sob processo de desertificaÃÃo no municÃpio de IrauÃuba, Cearà / Diagnosis of the occurrence of micro-organisms symbionts in areas under desertification process in the city of IrauÃuba, CearÃ

Aldenia Mendes Mascena 22 December 2014 (has links)
FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgico / A degradaÃÃo do solo resultante de prÃticas nÃo conservacionistas pode acarretar prejuÃzos irreparÃveis Ãs propriedades quÃmicas e biolÃgicas do solo de regiÃes semiÃridas do nordeste brasileiro. O objetivo do trabalho foi avaliar alguns atributos quÃmicos do solo, a densidade populacional de rizÃbios nativos, isolar e testar estirpes eficientes na fixaÃÃo simbiÃtica do nitrogÃnio atmosfÃrico no feijÃo-caupi (Vigna unguiculata (L.) Walp.), alÃm de avaliar a densidade de fungos micorrizicos arbusculares e a respiraÃÃo basal do solo em quatro Ãreas de exclusÃo (preservadas desde o ano de 2000) e de superpastejo (pecuÃria extensiva) localizadas no municÃpio de IrauÃuba-CE. Foram utilizadas quatro Ãreas de exclusÃo de animais e de superpastejo (adjacentes Ãs Ãreas de exclusÃo), sendo coletadas amostras de solos na profundidade de 0 a 20 cm para analisar alguns atributos quÃmicos (pH, CE, C, N, MO, e P assimilÃvel) e biolÃgicos do solo (densidade de esporos de fungos micorrizico arbusculares e rizÃbios nativos, respiraÃÃo basal do solo), alÃm do isolamento e teste de eficiÃncia das estirpes nativas em relaÃÃo a fixaÃÃo biolÃgica do nitrogÃnio atmosfÃrico. Os experimentos foram conduzidos em casa de vegetaÃÃo e no LaboratÃrio de Microbiologia do Solo pertencente ao Departamento de CiÃncias do Solo da Universidade Federal do CearÃ. Para os testes de eficiÃncia da fixaÃÃo simbiÃtica de nitrogÃnio atmosfÃrico das estirpes nativas isoladas das quatro Ãreas foi adotado um delineamento experimental inteiramente casualizado, com 4 repetiÃÃes. Na Ãrea 1 foram adotados nove tratamentos e quatro repetiÃÃes, sendo um controle com adiÃÃo de nitrogÃnio mineral (+N-R) e um com omissÃo de nitrogÃnio mineral e ausÃncia de inoculaÃÃo C(-N-R); na Ãrea 3 foram adotados oito tratamentos e quatro repetiÃÃes, sendo um controle com adiÃÃo de nitrogÃnio mineral (+N-R) e um com omissÃo de nitrogÃnio mineral e ausÃncia de inoculaÃÃo C(-N-R); na Ãrea 4 o teste foi composto de seis tratamentos e quatro repetiÃÃes, sendo um controle com adiÃÃo de nitrogÃnio mineral (+N-R) e um com omissÃo de nitrogÃnio mineral e ausÃncia de inoculaÃÃo C(-N-R); na Ãrea 5 o teste foi constituindo de quatro tratamentos e quatro repetiÃÃes, sendo um controle com adiÃÃo de nitrogÃnio mineral (+N-R) e um com omissÃo de nitrogÃnio mineral e ausÃncia de inoculaÃÃo C(-N-R). Os tratamentos diferenciados das quatro Ãreas foram estabelecidos de acordo com o total de estirpes isoladas e autenticadas de cada Ãrea de estudo. As atuais prÃticas de manejo do solo empregadas nas Ãreas de exclusÃo de animais (pousio) favoreceram a presenÃa de propÃgulos de fungos micorrÃzicos arbusculares no solo em decorrÃncia da preservaÃÃo da vegetaÃÃo e da conservaÃÃo da camada superficial do solo. As estirpes de rizÃbios nativas isoladas e testadas das Ãreas 1 e 5 estabeleceram simbiose com o feijÃo-caupi, demonstrado uma eficiÃncia fixadora do N 2 razoÃvel, podendo ser em futuros ensaios de competiÃÃo. Evidencia-se a necessidade de que mais estudos em relaÃÃo as propriedades quÃmicas e biolÃgicas dos solos de IrauÃuba-CE sejam realizadas, para que se possa buscar alternativas para a reduÃÃo dos efeitos negativos do processo de degradaÃÃo observados nas Ãreas em estudo. / The soil degradation resulting from non-conservative practices can cause irreparable damage to chemical and biological properties of the soil of semiarid regions in northeastern Brazil. The objective of this research was to evaluate the soil chemical attributes, the population density of rhizobia and its symbiotic fixing efficiency of the atmospheric nitrogen in cowpea (Vigna unguiculata (L.) Walp.) in addition to density of arbuscular mycorrhizal fungi and the basal soil respiration in four areas of exclusion and overgrazing located in the municipality of IrauÃuba-CE. Four areas of animal exclusion and overgrazing (adjacent to the exclusion areas) were chosen, with soil samples being collected in the 0 to 20 cm to analyze the chemical attributes pH, Electric Conductivity (EC), Carbon (C),Nitrogen (N), Organic Matter (OM), and assimilable Phosphorus (P) and biological attributes (arbuscular mycorrhizal fungi spores density, rhizobia density and effectiveness and basal soil respiration. The experiments were conducted under greenhouse conditions and, for the atmospheric symbiotic nitrogen fixation performance tests, native strains were isolated from the four areas and a completely randomized design, with four replications, was adopted. In area 1 were used nine treatments and four replications, with a control with the addition of mineral nitrogen (+N-R) and another with mineral nitrogen omission and no inoculation C(-N-R); in area 3 were used eight treatments and four replications, with a control with the addition of mineral nitrogen (+N-R) and with mineral nitrogen omission and no inoculation C(-N-R); in area 4 the test consisted of six treatments and four replications, with a control with the addition of mineral nitrogen (+N-R) and with mineral nitrogen omission and no inoculation C(-N-R); in area 5 the test were used four treatments and four replications and a control with the addition of mineral nitrogen (+N-R) and another with mineral nitrogen omission and no inoculation C(-N-R). The different treatment numbers of the four areas were established according to the total number of isolated and authenticated strains of each study area. The current soil management practices employed in the areas of exclusion of animals (fallow) favored the presence of propagules of arbuscular mycorrhizal fungi in the soil due to the preservation of vegetation and conservation of topsoil. Native rhizobia strains isolated and tested from Areas 1 and 5 established symbiosis with the cowpea and demonstrated a fixing efficiency of N 2 reasonable and can be used in future field trials. More studies on the chemical and biological properties of soils IrauÃuba-CE should be performed so that we can find alternatives for reducing the negative effects of the degradation process observed in the areas under study.
54

Analise parametrica da estabilidade de plataformas ferroviarias degradadas / Parametric evaluation of degraded railway subgrade stability

Aguiar, Paulo Roberto 22 August 2007 (has links)
Orientador: Cassio Eduardo Lima de Paiva / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-09T09:00:02Z (GMT). No. of bitstreams: 1 Aguiar_PauloRoberto_M.pdf: 2785267 bytes, checksum: 6bde50559dcc0d0d8052701ee543e1b3 (MD5) Previous issue date: 2007 / Resumo: O estudo desenvolvido neste trabalho consiste na avaliação da capacidade de suporte do subleito ferroviário, através da determinação do risco à ruptura circular da plataforma, de uma secção transversal de um pátio ferroviário sujeito à carga de um veículo estacionado em uma via lateral, são utilizadas as equações. Para fins de desenvolvimento do presente estudo é utilizado o método de Eisenmann para determinação das tensões atuantes na base do trilho. As tensões atuantes na plataforma são calculadas através das equações de Carothers-Terzaghi. A avaliação do risco à ruptura circular é feita através do programa computacional GEOSLOPE-SLOPE/W versão 6. Após a determinação dos fatores de segurança à ruptura para várias situações analisadas, é feita a análise dos resultados obtidos no sentido de determinar as situações de risco de estabilidade da via à ruptura circular da plataforma / Abstract: This study deals with an evaluation of subgrade capacity by determining the circular rupture stability risk of a slope adjacent to a railway yard track subject the tensions of a loaded gondola car parked in this track. The Eisenmann method is applied for determination of tensions at the railway subgrade and the tensions are calculated by means Carothers-Terzaghi equations. The analysis of circular failure risk is made by means of the computer software Geoslope-Slope/W version 6. After calculating the safety factors for many situations, the results are evaluated to stablish the stability risks of the slope adjacent to the railway track / Mestrado / Transportes / Mestre em Engenharia Civil
55

Enriquecimento de uma floresta em restauração através da transferência de plântulas da regeneração natural e da introdução de plântulas e mudas / Diversity enhancement of a forest under restoration process through understorey seedlings transplanting and introduction of nursery seedlings

Milene Bianchi dos Santos 12 September 2011 (has links)
A restauração de áreas degradadas tem como objetivo a formação de um ambiente florestal e o restabelecimento das interações entre espécies vegetais e animais que auxiliam na manutenção das populações locais e a evolução da comunidade implantada. Atualmente, existe a preocupação com a qualidade das áreas restauradas no Estado de São Paulo nos últimos anos em relação à perda da diversidade biológica e ao estado de declínio em que se encontram, principalmente devido ao isolamento dessas áreas na paisagem. Considerando a contínua expansão econômica e a construção de obras que acarretam o corte legalizado de áreas naturais, a utilização dos recursos dessas áreas pode se tornar uma alternativa para a restauração de áreas degradadas através da obrigatoriedade de ações mitigadoras e compensatórias. A transferência de plântulas dessas áreas é uma técnica utilizada para a produção de mudas de elevada riqueza de espécies e formas de vida que podem ser utilizadas no enriquecimento de áreas em processo de restauração ou de florestas secundárias degradadas. O isolamento desses fragmentos dificulta a chegada de novas espécies na área, mesmo após a formação do dossel que propicia um ambiente adequado ao estabelecimento de guildas como as espécies de sub-bosque. Dessa forma, torna-se necessária a introdução assistida de novas espécies nessas áreas para o restabelecimento de interações ecológicas e auto-perpetuação da floresta. O objetivo deste estudo foi analisar diferentes técnicas de enriquecimento em uma Floresta Estacional Semidecidual em processo de restauração. O estudo foi realizado em um fragmento localizado no município de Santa Bárbara dOeste, SP. Foram coletadas plântulas de uma área que seria legalmente suprimida e transferidas para o viveiro visando à produção de mudas. Posteriormente, mudas de vinte espécies foram plantadas no fragmento de Floresta Estacional Semidecidual e apresentaram elevadas taxas de sobrevivência. Nesta mesma área foi realizado o plantio de plântulas e mudas de espécies de subbosque produzidas em viveiro. Foram plantadas sete espécies de plântulas e dez espécies de mudas na entrelinha do plantio original que durante o período de avaliação apresentaram elevadas taxas de sobrevivência. Deste modo, esses resultados demonstram a viabilidade da técnica de transferência de plântulas da regeneração natural, do plantio de plântulas e mudas de espécies de sub-bosque visando o enriquecimento de áreas em processo de restauração. / The main objective of ecological restoration is to built a forested environment and reestablish plants and animals interactions, which promotes the maintenance of local populations and the development of the restored community. Nowadays, there is concern about the quality of restored forests in the São Paulo State (Brazil), regarding their biodiversity loss, related to the landscape isolation on which they are found. Considering the fact that economic expansion and building works result on legalized deforestation, the good use of these natural resources may consist on an interesting alternative to restoration ecology. Transplanting seedlings from these condemned areas is a technique that aims to gather high diversity of species and lifeforms that can be used to enhance diversity on restored sites or secondary forests. Isolation of forest remnants raise difficulties to the arrival of colonizing species, even after a canopy is formed and therefore a suitable environment for the establishment of guilds such as understorey species is available. For that matter it is necessary to assist the introduction of new species to these areas under reforestation process, reestablishing ecological interactions and forest self- maintenance. The main purpose of this study was to analyze different techniques of diversity enhancement of a Seasonal Semideciduous Forest under restoration process. The study was taken on a forest remnant located at Santa Barbara d\'Oeste (São Paulo State). Seedlings were transplanted from a site to be legally deforested and taken to a seedling nursery. Then, seedlings of 20 species were planted on a forest remnant and presented high survival rates. At this same site, seedlings produced under nursery conditions were planted; seven understorey species of young seedlings and ten understorey species of regular sized seedlings were transplanted to a restored forest and presented high survival rates during evaluation period. The results add evidence that transplanting seedlings from forest understorey and from nurseries is a feasible technique to enhance diversity on restoring forests.
56

Effets des amendements organiques exogènes sur la composition de la matière organique et le stockage du carbone d'un sol dégradé par l'érosion dans le Nord du Vietnam / Effects of exogenous organic amendments on carbon storage and soil organic matter composition in erosion-degraded soil in Northern Vietnam

Ngo, Thi Phuong 06 May 2014 (has links)
Une stratégie pour améliorer durablement la fertilité des sols dégradés par érosion au Nord du Vietnam consiste à apporter des amendements organiques exogènes (AOEs). L'application du lisier de buffle, son compost et lombricompost, ainsi que le biochar permettraient à faible coût d’améliorer la qualité des sols et la croissance des plantes en réduisant l'utilisation d'engrais, mais également de séquestrer du carbone. L’objective de cette thèse est d’évaluer (1) l’utilité des quatre AOEs seuls ou en association pour séquestrer du carbone, et (2) l’effet de l’apport des quatre substrats organiques seuls ou en association sur la quantité et qualité des matières organiques d’un sol agricole tropical dégradé typique du Nord du Vietnam. Pour répondre à cet objectif, nous avons effectué des incubations au laboratoire, en sachet de litière dans des conditions de terrain et suivi pendant trois ans une expérience en mesocosme avec ajouts des AOEs au sol cultivé en conditions de terrain.Nos résultats montrent que le compostage en présence de vers de terre conduit à une plus forte transformation de la matière organique issue du lisier de buffle par rapport au compostage traditionel. Le lombricompost était enrichi en composés azotés et appauvri en polysaccharides, et se caractérisait par une altération plus importante des lignines en comparaison avec le compost. La stabilité biologique de ces AOEs a été liée à leur teneur en carbone soluble, diminuant suivant l’ordre : lisier de buffle > compost > lombricompost, alors que leur réactivité chimique était similaire. Le biochar, constitué de carbone aromatique, se caractérisait par une très forte stabilité biologique et chimique. L’association du biochar avec les autres AOEs a influencé leur stabilité chimique et biologique, en protégeant la matière organique labile contre l'oxydation chimique et la dégradation biologique.Notre expérience de trois ans en mésocosmes en conditions naturelles a montré que tous les AOEs ont un effet positif sur le stockage du carbone dans le sol ainsi que sur la qualité de la matière organique de sol. L’association de biochar et de lombricompost en augmenttant l’abondance des composés dérivés de la lignine ainsi que la teneur en sucre provenant des plantes et des microorganismes, semble montrer un effet synergique de cette association sur la fertilité des sols (activité microbienne, prospection racinaire). Comparé aux résultats d’incubation en sachet de litières, ces résultats indiquent un effet significatif et contrasté des AOEs sur la croissance des plantes en particulier sur l’apport racinaire. En conclusion, l’association de biochar et de lombricompost semble la meilleure solution pour améliorer la qualité de sol dégradé par l'érosion dans le Nord du Vietnam. Ces résultats devront être confirmés par des études à long terme, tant du point de vue de la qualité physicochimique que biologique des sols amendés par ces AOEs. / Intensification of agricultural use of tropical soils in Northern Vietnam leads to acidification associated with organic matter loss, rapid decline of their fertility and high erosion rates. Such negative effects may be counteracted by exogenous organic amendments (EOMs). The application of buffalo manure, its compost and vermicompost and biochar alone or in mixture with other EOMs is promising to improve at low cost soil quality, plant growth and carbon sequestration. The aims of this study were to evaluate (1) the usefulness of the four EOM alone or in mixture to sequester carbon and (2) the effect of these amendments on quantity and quality of soil organic matter of a tropical soil degraded by erosion. To anwer to this objective we carried out incubations in the laboratory, in litterbags under field conditions and we monitored a mesocom experiment, where the EOM were added and subjected during three years to cultivation and natural rainfall conditions. Our results showed that composting in the presence of earthworms led to stronger transformation of buffalo manure than regular composting. Vermicompost was enriched in N-containing compounds and depleted in polysaccharides. It further contained stronger modified lignin compared to regular compost. Biological reactivity of these AOEs was related to their soluble organic matter content, which decreased in the order buffalo manure > compost > vermicompost, whereas their chemical reactivity was similar. Bamboo biochar was enriched in aromatic carbon and characterized by a high biological and chemical recalcitrance. The presence of biochar influenced the biological as well as chemical reactivity of the other organic amendments. It led to a protection of organic matter against chemical oxidation and changed their susceptibility to biological degradation. Our experience with mesocosmes during 3 year under the natural conditions showed that all organic amendments had a positive effect on soil carbon storage and significantly influences soil organic matter quality. Biochar could increase the soil carbon sequestration potential, when applied in mixture with vermicompost. The presence of biochar increased lignin derived compounds abundance as well as both plant and microbial sugar content of soil amended with vermicompost but it had no effect in the case of control soil. Compared to our litterbag experiment these results show that EOM have a strong contrasting effect on plant growth, in particular root litter input. In conclusion, the incorporation of biochar and vermicompost seems to be the best solution to improuve the quality of degraded soil in Northem Vietnam. More studies about the impacts of this amendment on soil physico-chemical and biological properties in long-term are needed to comfirm these results.
57

The Internal Validation and Casework Application of MiniSTR Systems

Kleyn, Eugene Lyle January 2008 (has links)
Magister Scientiae - MSc / The objective of the study was to conduct an internal validation on miniSTR systems and apply it to cases received from the South African Missing Persons Task Team (SAMPTT). This was prompted by the fact that miniSTR systems have been shown to out perform some of the commercial kits available in the time of the study and provide an alternative to mtDNA when analysing degraded DNA from skeletal remains and that the DNA extracted from skeletal remains received from the SAMPTT would be degraded due to the remains generally being fragmented or charred and buried for many years. The miniSTR loci chosen for validation comprised the Combined DNA Index System (CODIS) thirteen core loci and were arranged into four triplexes and one uniplex. / South Africa
58

The effects of emotional prosody on perceived clarity in degraded speech

Lindqvist, Rasmus January 2021 (has links)
The ability to hear is important to communicate with other people. People suffering from hearing loss are more likely to also suffer from loneliness and depression (Mener et al., 2013; Mo et al., 2005). To understand how degraded speech is recognized, the pop-out effect has been studied. The pop-out effect is the moment when a listener recognizes the meaning of degraded speech. Previous research on the pop-out effect in perception of speech has predominantly been focused towards top-down processes, such as form-based priming and semantic coherence in sentences. The purpose of this study was to research the relationship between emotional prosody and the perception of speech in varying levels of degraded speech. The participants were presented sentences with angry, neutral or happy prosody in varying levels of noise vocoding. The participants were then asked to rate the perceived amount of noise for each sentence, and if the prosody was perceived as positive, neutral or negative for each sentence. The results suggest that the participants' ability to perceive positive prosody in the sentences decreased more rapidly than negative as the amount of noise increased. The result did not show any statistically significant evidence that emotional prosody had any effect on the perceived amount of noise. Future research should further investigate emotional prosody together with emotional semantics, as an emotionally coherent spoken sentence, and the influences on speech perception in adverse listening conditions, in order to further investigate the factors contributing to the pop-out effect.
59

Dyslexia and the Perception of Indexical Information in Speech

Beam, Gaylene P. 29 August 2019 (has links)
No description available.
60

Computational methods for the objective review of forensic DNA testing results

Gilder, Jason R. 31 July 2007 (has links)
No description available.

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