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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.
131

Identification of a putative two-component gold-sensor histidine kinase regulator in Stenotrophomonas maltophilia OR02

Zack, Andrew M. 11 May 2020 (has links)
No description available.
132

Evaluation of heavy metals in soil : a case study of platinum tailing dam site

Nkobane, Molebogeng Precious 09 1900 (has links)
Mining industry has been identified as the main sustenance of the South African economy, however the negative impacts of the industry on the ecological systems cannot be over emphasized due to the released waste which is mostly heavy metals into the environment. The study evaluated six heavy metal (A1, Cu, Fe, Ni, Pb and Cr) contents in a tailings dam from a specific mine site. Two sets of samples for the investigation were measured, that is, one in year 2012 and the other in year 2013. In the year 2012, the sample set was only taken at a distance profile of 500 meters from the foot of the dam, whereas the sample set taken in the year 2013 was for the 500 and 1500 meter distance profiles from the foot of the dam. The year 2012 and 2013 sample sets for the 500m distance profile were sampled very similarly to each other. A kilogram of each sample was taken as per grid format. The samples at varied depths were taken at 0-cm depth for the top layer, 20cm depth for the second layer, and 30cm depth for the third layer. The samples for the surface varied distance were taken at 1 m, 2m, 3m, and 4m away from each 500m and 1500 sampling points. The 2012 samples were analysed using characterization methods namely ICP MS and The 2013 samples were analysed using the ICP OES. The comparison of the field results for the six heavy metals studied (A1, Fe, Pb, Cu, Ni and Cr) was performed using statistical analytical methods, namely ANOVA. The statistical analysis results for heavy metals (A1, Fe, Pb, Cu, Ni and Cr) from sample and 2013 revealed that the group means are not significantly different from each other which means that there is no significant difference in (A1, Fe, Pb, Cu, Ni and Cr) concentrations with respect to both depth and distance. The observations from both 2012 and 2013 indicate the results of the samples are in agreement. In addition, the comparative average concentrations of the three results obtained reach the same conclusion that the tailing dam probably does not introduce considerable or significant amounts of these metals (A1, Fe, Pb, Cu, Ni and Cr) into the surrounding soils. / Chemical Engineering / M. Tech. (Chemical Engineering)
133

Unlocking the Paradox of Christian Metal Music

Strother, Eric S. 01 January 2013 (has links)
In 1984, Stryper released its first album The Yellow and Black Attack and introduced audiences to a different kind of heavy metal. Instead of lyrics about sex, alcohol, and Satan, Stryper sang about Jesus, salvation, and God. While there were a number of fans ready for this change more were not. Members of the Church as well as members of the metal subculture were in agreement that Christianity and heavy metal were incompatible. Despite these objections, however, more bands emerged, and Christian metal became a significant genre within the Christian music industry. These bands presented Christian-oriented lyrics within the full spectrum of metal subgenres. This dissertation examines the ways in which Christian metal bands create an intersection between Christianity and the heavy metal subculture, infusing Christianity within the textual, visual, and musical structures of heavy metal. The author employs Deena Weinstein’s “metal code” to frame the analysis. The metal code includes the textual elements (band names, album and song titles, and song lyrics); the visual elements (band logos; album covers; and the various elements of the concert experience including the bands’ appearances, the staging, the interactions with the fans, and music videos); and the musical elements (timbre, modality, formal structure, and production of the songs and albums) that set metal apart from other musical genres. The dissertation also examines the concept of bands as “metal missionaries” that immerse themselves within the heavy metal subculture for the purpose of bringing the Christian message of hope and salvation. The author concludes that even though Christian metal bands modify aspects of elements that are otherwise incompatible with their Christian beliefs and message, they still maintain a sense of stylistic integrity that gives them credibility within the heavy metal subculture and allows them to fulfill their mission.
134

Traffic-Related Metals in Soil and Sediment in Mauritius / Trafikrelaterade metaller i jord och sediment på Mauritius

Petersson, Liselott January 2005 (has links)
<p>Trafik utgör en stor föroreningskälla av tungmetaller i vägnära jordar och särskilt är det koppar (Cu), bly (Pb) och zink (Zn) som associeras med fordonstrafik. I ett historiskt perspektiv härrör blyutsläpp främst från bränsleförbränning, medan kopparemissioner (i första hand från slitage av bromsbelägg) och zinkutsläpp (från däck) från trafik står för så mycket som hälften av det urbana utsläppet av koppar och zink till omgivningen.</p><p>Koppar-, bly- och zinkkoncentrationer i vägnära jord och sediment undersöktes inom avrinningsområdet för Grand River North West i Mauritius. Eftersom totalmetall utgör en dålig indikator på den mängd metall som finns potentiellt tillgänglig för biota användes extraktion med hjälp av 0.5 M HCl tillsammans med totalkoncentrationer.</p><p>Den rumsliga variationen längsmed transekt vinkelrätt mot vägar undersöktes liksom variationen med djupet. Observerade kopparkoncentrationer var jämförbara med bakgrundsnivåer. Till skillnad från Cu var koncentrationer av Pb och Zn förhöjda i den omedelbara närheten till vägar med relativt stor trafikintensitet, men halterna minskade snabbt med avståndet. Resultat från platserna för jordreferenser visar på storskalig förorening av Pb på ön. Uppmätta kopparkoncentrationer kunde inte knytas till trafikens påverkan.</p><p>Vid regn kan metaller som finns i förorenat vägdamm och förorenad jord övergå till löslig form, eller sköljas bort i partikulär form, och transporteras till närliggande vattendrag. I Mauritius är det här av speciell vikt eftersom flodsediment till slut kommer att deponeras i de känsliga kustområdena som omger ön. Dock tyder inte resultaten på förhöjda metallhalter i sediment nära de studerade vägarna.</p><p>Även om erhållna resultat av Cu inte visar på någon förhöjning och zonen med hög förorening av Pb och Zn är relativt smal, är det angeläget att följa utvecklingen eftersom antalet fordon växer snabbt i Mauritius, vilket kan förändra dagens situation och ge upphov till större miljöpåverkan. För att undvika eventuella ekologiska skador är det därför av stor vikt att i fortsättningen övervaka situationen längs landets vägar.</p> / <p>Traffic has been identified as a significant heavy metal polluter of roadside soils, and copper (Cu), lead (Pb) and zinc (Zn) in particular are associated with road travel. In a historic perspective, the Pb contribution from anthropogenic sources to nature has predominantly been a result of fuel combustion. There are indications that Cu (mainly through braking system) and Zn (emissions from tires) released from traffic give rise to as much as half of the total urban contribution of copper and zinc to the environment.</p><p>Concentrations of Cu, Pb and Zn in roadside soils and sediment have been determined at selected roads within the Grand River North West watershed in Mauritius. As total metal concentrations are not a suitable indicator of the metal concentrations that are potentially available to biota, metals extractable in 0.5 M HCl have been determined along with total concentrations. The spatial variation in metal concentration along soil transects perpendicular to roads were investigated, as was the variation with depth.</p><p>Observed Pb and Zn concentrations exhibited elevated levels in topsoil in the immediate vicinity of roads with relatively large traffic densities, but the decrease in concentration with distance was rapid. Results from soil reference sites pointed to a large scale Pb pollution on the island. In comparison, observed Cu concentrations could not be assigned any influence from traffic at the selected study sites.</p><p>In the event of rain, metals contained in polluted road dust and soil may be released into soluble form, or flushed from roadways as particulate matter, and transported to nearby water courses. In Mauritius, this is of particular importance as sediment in rivers eventually may be deposited in the sensitive coastal areas of the island. However, results do not indicate that there were any elevated levels of heavy metals in sediment close to roads that were investigated in this study.</p><p>Although Cu concentrations in roadside soils did not show any enrichment and the zone of elevated Pb and Zn concentrations was not wide, there is a concern that the continuing rapid increase in the number of vehicles in Mauritius will change the situation, possibly resulting in greater impact on the surrounding environment. Hence, in order to avoid any ecological damage, it is desirable to continue monitoring the situation along highways in the country.</p>
135

Copper, manganese, and zinc in Puerco River sediments

Henshel, Judy, 1958- January 1988 (has links)
A study was conducted to test for the presence of heavy metals (Cu, Mn, and Zn) in surface sediments of the Puerco River channel in the aftermath of a toxic spill in 1979 near Church Rock, New Mexico. Analysis of samples from five sites downstream from the spill showed that these substances were not present in unusually large amounts, though an increasing gradient of metal concentration with distance downstream was revealed. Statistical analysis revealed the Cu, Mn, and Zn were associated with clay and silt, soil organic matter, organic carbon, and carbonates, all of which existed as extraneous, uncontrolled variables. Adjusted metal concentrations, obtained with covariate analyses, confirmed the increasing gradient downstream. Clay and silt also increased downstream. Some toxic substances may have leached into the riverbed; possible mechanisms for this process are also discussed and further study to substantiate or disprove this hypothesis is recommended.
136

Word Salad

Liberto, Anthony 01 January 2007 (has links)
I've always considered myself a serious person who understood the meaning of labor. I am determined to labor over my ideas, and to labor seriously. The problem, and by "problem," I mean, "best thing" about this is that no one takes me seriously. Ever. They seem to like my work anyway. Apparently, I'm more funny than I am serious. But that's okay, because, secretly, I think I've always tried to be serious because I never thought I was smart enough to be funny. I often misunderstand things. Sometimes I mishear or wrongly attribute or think that facts are a metaphors or that metaphors are facts. Then I take this (mis)information back to my studio and playing Cosmic Matchmaker, yoking together seeming disparate elements to create a visual vocabulary. And then I labor over it. Very seriously.
137

"Not eager to fit in" : The collective work of creating an alternative cosmology of Heavy Metal

Schug, Lisa January 2017 (has links)
The celebration of a White heteronormative masculinity is still vivid in Heavy Metal. This has embodied and discursive consequences that are visible in the domination of Metal spaces or the marginalisation of female, trans* or non-binary musicians, but also in an aesthetics of (hetero- and cis-) sexism and racism that is often apparent. Nevertheless, Metal is still empowering and joyful for those who experience exclusion and marginalisation. They have found ways to react and organise an alternative participation in Heavy Metal. Using a queered approach to Cultural Studies, this study aims at intervening in the continuous reproduction of a normative White and straight Metal masculinity. Collecting data from five ethnographic interviews with queer Metalheads and additional autoethnographic data, it shows how queer Metalheads organise their participation in Heavy Metal and create an alternative Metal cosmology. This study is not only a theoretical intervention. As a result of the interview project, a new community of queer Metalheads was created.
138

Investigating the tomato tolerance to cadmium (Cd) via high throughput proteomics / Investigando a tolerância de tomate ao (Cd) via proteômica de alto rendimento

Nogueira, Marina de Lima 30 April 2019 (has links)
The problem of cadmium (Cd) toxicity aggravates every year. However, the amount of plant species presenting some degree of tolerance to this metal is low. Therefore, it is of utmost importance to understand the Cd tolerance mechanisms. Two tomato cultivars exhibiting distinct levels of tolerance to Cd were investigated by exposing them to 35 &#956;m de CdCl2 for eight days. The samples (roots, stems, and leaves) were collected at 0, 2, 4, 6 and 8 days. The root length and surface area were obtained using a WinRhizo PRO 2009c image analyzer. The ICP OES method was used for the quantification of metals in the different tissues. The translocation index (TrI), metal uptake and Cd distribution nutrient absorbed (NA), and nutrient efficiency (NUE) were calculated. The plant material used for stress indicators and proteomics analysis were collected in liquid nitrogen. Lipid peroxidation and H2O2 contents were obtained by spectrometry. For the proteomics data the gel-free method was used. The stress indicators showed the variation in both cultivars, evidencing the stress caused by the Cd. Chlorosis and necrotic spots were observed in plants exposed to Cd less significant way in the first days of exposure and more evident in the less tolerant cultivar (TTO) in the last days. The growth reduction can be observed in both cultivars, more evident in TTO. Regarding the Cd distribution, the two cultivars showed similar behavior, with the highest percentage of Cd in the roots. The Cd absorption could interfere with both cultivars in the accumulation absorption and efficiency in the use of most nutrients assessed. In general, the Cd interference was more evident at TTO than at YOSH. Highest percentages of TrI were also observed in TTO cultivar. Identification and evaluation of the differentially accumulated protein (DAP) in the two cultivars roots it is possible to observe that in the presence of Cd the cultivar TTO generates a more significant alteration in the amplitude of the accumulation and the number of proteins. These results suggest that the cultivar, which presents a higher degree of tolerance, has some form to make the Cd unavailable or a mechanism that makes the Cd transportation to the leaves more difficult. / O problema da toxicidade do cádmio (Cd) agrava-se a cada ano. No entanto, a quantidade de espécies de plantas que apresentam algum grau de tolerância a este metal é baixa. Portanto, é de suma importância entender os mecanismos de tolerância do Cd. Com esse intuito duas cultivares de tomate (TTO e YOSH) exibindo níveis distintos de tolerância ao Cd foram investigadas, expondo-as a 35 &#956;m de CdCl2 por oito dias. As amostras (raízes, caules e folhas) foram coletadas aos 0, 2, 4, 6 e 8 dias. O comprimento da raiz e área de superfície foram obtidos usando um analisador de imagem WinRhizo PRO 2009c. O método ICP OES foi utilizado para a quantificação de metais nos diferentes tecidos. O índice de translocação (Trl), a absorção de metal e a distribuição de Cd dos nutrientes absorvidos (NA) e eficiência de nutrientes (NUE) foram calculados. O material vegetal usado para indicadores de estresse e análise proteômica foi coletado em nitrogênio líquido. A peroxidação lipídica e o teor de H2O2 foram obtidos por espectrometria. Para os dados proteômicos, foi utilizado o método livre de gel. Os indicadores de estresse mostraram a variação nas duas cultivares, evidenciando o estresse causado pelo Cd. A clorose e manchas necróticas foram observadas em plantas expostas ao Cd de maneira menos significativa nos primeiros dias de exposição e mais evidentes no cultivar menos tolerante (TTO) nos últimos dias. A redução do crescimento pode ser observada em ambas as cultivares, mais evidente no TTO. Quanto à distribuição de Cd, as duas cultivares apresentaram comportamento semelhante, com o maior percentual de Cd nas raízes. A absorção de Cd pode interferir nas duas cultivares na absorção, acúmulo e eficiência no uso da maioria dos nutrientes avaliados. Em geral, a interferência do Cd foi mais evidente no TTO do que no YOSH. As maiores porcentagens de TrI também foram observadas na cultivar TTO. Identificação e avaliação da proteína diferencialmente acumulada (DAP) nas raízes das duas cultivares é possível observar que na presença de Cd a cultivar TTO gera uma alteração mais significativa na amplitude do acúmulo e no número de proteínas. Estes resultados sugerem que a cultivar, que apresenta um maior grau de tolerância, tem alguma forma de tornar o Cd indisponível ou um mecanismo que dificulte o transporte de Cd para as folhas.
139

Evaluation of heavy metals in soil : a case study of platinum tailing dam site

Nkobane, Molebogeng Precious 09 1900 (has links)
Mining industry has been identified as the main sustenance of the South African economy, however the negative impacts of the industry on the ecological systems cannot be over emphasized due to the released waste which is mostly heavy metals into the environment. The study evaluated six heavy metal (A1, Cu, Fe, Ni, Pb and Cr) contents in a tailings dam from a specific mine site. Two sets of samples for the investigation were measured, that is, one in year 2012 and the other in year 2013. In the year 2012, the sample set was only taken at a distance profile of 500 meters from the foot of the dam, whereas the sample set taken in the year 2013 was for the 500 and 1500 meter distance profiles from the foot of the dam. The year 2012 and 2013 sample sets for the 500m distance profile were sampled very similarly to each other. A kilogram of each sample was taken as per grid format. The samples at varied depths were taken at 0-cm depth for the top layer, 20cm depth for the second layer, and 30cm depth for the third layer. The samples for the surface varied distance were taken at 1 m, 2m, 3m, and 4m away from each 500m and 1500 sampling points. The 2012 samples were analysed using characterization methods namely ICP MS and The 2013 samples were analysed using the ICP OES. The comparison of the field results for the six heavy metals studied (A1, Fe, Pb, Cu, Ni and Cr) was performed using statistical analytical methods, namely ANOVA. The statistical analysis results for heavy metals (A1, Fe, Pb, Cu, Ni and Cr) from sample and 2013 revealed that the group means are not significantly different from each other which means that there is no significant difference in (A1, Fe, Pb, Cu, Ni and Cr) concentrations with respect to both depth and distance. The observations from both 2012 and 2013 indicate the results of the samples are in agreement. In addition, the comparative average concentrations of the three results obtained reach the same conclusion that the tailing dam probably does not introduce considerable or significant amounts of these metals (A1, Fe, Pb, Cu, Ni and Cr) into the surrounding soils. / Chemical Engineering / M. Tech. (Chemical Engineering)
140

Concentrations of lead, copper and zinc in forest soils near industrial areas

Galyas, Éva January 2019 (has links)
Environmental contamination with heavy metals, especially of soils, has been a continuousproblem worldwide since the beginning of the industrial revolution. Heavy metal emissionshave increased continuously since 1900 and the metals accumulate in the environment. Pulpand paper mill factories, and factories which produce sulphuric acid emit heavy metals,among others lead (Pb), copper (Cu) and zinc (Zn). Results from previous studies showedthat the soils near factories had higher concentrations of these pollutants than the controlplace. In this study I want to determine the effects of industrial heavy metal emissions of onehistoric and one present industry on nearby soil heavy metal concentrations.Samples were taken near one historically heavily contaminated site, the old sulphite factoryin Rydöbruk (1897-1944) and near the present Stora Enso paper mill in Hyltebruk. As acontrol site, I compared these with Rocknen nature reserve area.At each site I took 6 soil samples, representing the top 15-20 cm of soil and organic material.Samples were analysed with an Atomic Absorption Spectrometer and the concentrations oflead, copper and zinc were determined per ashed dry material.I analyzed the samples at the laboratory using the guideline from the Swedish StandardInstitute for water analysis.The concentrations of the soil samples showed no significant difference between the naturereserve area and the industrial sites (One-way ANOVA). This was due to very variableorganic content within and between the sites.Organic content of the samples has a significantly effect on the metal concentrations for Pband Cu (Linear Regression test). In conclusion, metals can accumulate in the vegetation, andin case of Pb and Cu there is a correlation between their concentration and the amount oforganic matter. Therefore in future studies it is best if soil with very high organic content orvegetation is used to determine if forest soil near industries are affected by past or presentindustrial emissions of heavy metals.

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