• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 19
  • 18
  • 11
  • 5
  • 2
  • 2
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • Tagged with
  • 72
  • 6
  • 6
  • 5
  • 5
  • 5
  • 5
  • 4
  • 4
  • 4
  • 4
  • 4
  • 4
  • 4
  • 4
  • 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.
1

Volume-activated chloride currents in a cancer cell line

Killey, Jennifer January 2002 (has links)
No description available.
2

Volume-sensitive membrane transport in Xenopus laevis erythrocytes

Lancaster, Jo-Ann M. January 1997 (has links)
No description available.
3

Laboratory evaluation of surface treatments to asphaltic pavements in Mississippi

Jordan, Walter Stephens 01 May 2010 (has links)
Chip and scrub seal treatments are one of the most common pavement preservation practices, however, no performance specifications exist in Mississippi. Review of literature has shown the treatment of cores being successful in reducing the viscosity of aged asphalt pavements. The purpose of this thesis is to provide a basis for performance based specifications for surface treatments in Mississippi. This thesis provides information pertaining to viscosity, moisture loss, and frosted marble analysis of emulsions and the effects of rejuvenation after application of emulsions to aged asphalt pavements which are vital to the performance of the surface treatment. The objectives to this thesis are to determine and evaluate the effects of rejuvenation, frosted marble test, and moisture loss of emulsion applied to aged asphalt pavements. Results from these analysis’ are favorable for developing or providing a basis for performance based specifications for surface treatments applied in Mississippi.
4

Estudo da redução de pelotas de minérios de ferro por hidrogênio e mistura de hidrogênio com monóxido de carbono. / Study of reduction of iron pellets for hydrogen and hydrogen mixture with carbon monoxide.

Rodrigues, Girley Ferreira 10 March 2014 (has links)
O problema da emissão de gases de efeito estufa é uma questão que tem ganhado destaque nas recentes convenções internacionais. Adiciona-se a esta questão o fato de o setor siderúrgico ser responsável por parcela significativa nas emissões de gases de efeito estufa. O presente trabalho tem por objetivos estudar processos de redução de minérios de ferro usando hidrogênio e hidrogênio mais monóxido de carbono como redutor para o processo de redução, visando assim à diminuição nas quantidades de CO2 liberadas pelo processo de redução de minérios de ferro. Os minérios foram caracterizados por Microscopia Eletrônica de Varredura, difração de raios-X, quantificação de fases pelo método Rietveld e distribuição granulométrica. Os ensaios de redução foram realizados em balança termogravimétrica e em forno tubular horizontal. A caracterização dos produtos foi realizada usando imagens obtidas por Microscopia Eletrônica de Varredura. Foi constatado que os aumentos da temperatura de redução e do fluxo de gás redutor provocam uma maior degradação física das pelotas. Verificou-se que ocorre a formação de whiskers na superfície externa das pelotas, sendo estes mais frequentes quando do fluxo combinado de H2+CO. Verificou-se que as pelotas reduzidas por hidrogênio puro resultaram em maior porosidade tanto no corpo da pelota ou mesmo no interior das partículas. Foi constatado que ocorre a redução homogênea em todas as partículas componentes da pelota. Foi constatado também que o estudo cinético através dos métodos combinados Jump-FSIA é aplicável na redução direta de pelotas de minério de ferro por H2 e H2+CO. Nas pelotas conformadas a partir de pellet feed com maior área de superfície específica (mais ativas), tanto a cinética quanto a taxa de redução indicaram que a adição de CO ao gás redutor não influi no processo de redução. A teoria de Sestak-Berggren sugere que o mecanismo controlador na reação global é a difusão podendo estar aliado a outras etapas, compondo um mecanismo misto. / The problem of the emission of greenhouse gases is an issue that has gained prominence in recent international conventions. Is added to this question the fact that the steel industry is responsible for a significant portion of emissions of greenhouse gases. The present work aims to study ways of reducing iron ore using hydrogen and hydrogen plus carbon monoxide as a reducing agent to the reduction process, thus aiming to decrease the amounts of CO2 released by reduction of iron ores process. The ores were characterized by Scanning Electron Microscopy, X-ray diffraction, phase quantification by Rietveld method and particle size distribution. The reduction assays were performed in thermogravimetric balance and horizontal tubular oven. The characterization of the products was performed using images obtained by scanning electron microscopy. It was found that increases in temperature and reduction in the flow of reducing gas cause greater physical degradation of the pellets. It was found that the formation of whiskers on the outer surface of the pellets occurs most frequently found when combined flow of H2+CO. It was found that the pellets reduced with pure hydrogen resulted in much higher porosity in the body pellet or even within the particles. It was found that the homogeneous reduction occurs in all components of the particle pellet. It was also found that the kinetic study using the combined methods Jump- FSIA applies in the direct reduction of iron ore pellets by H2 and H2+CO. In shaped pellets from pellet feed with higher specific surface area (more active), both the kinetics as the rate of reduction indicated that the addition of CO to the reducing gas has no effect on the reduction process. The Sestak - Berggren theory suggests that the mechanism controlling the overall reaction is diffusion can be combined with other steps, forming a mixed mechanism.
5

Estudo da redução de pelotas de minérios de ferro por hidrogênio e mistura de hidrogênio com monóxido de carbono. / Study of reduction of iron pellets for hydrogen and hydrogen mixture with carbon monoxide.

Girley Ferreira Rodrigues 10 March 2014 (has links)
O problema da emissão de gases de efeito estufa é uma questão que tem ganhado destaque nas recentes convenções internacionais. Adiciona-se a esta questão o fato de o setor siderúrgico ser responsável por parcela significativa nas emissões de gases de efeito estufa. O presente trabalho tem por objetivos estudar processos de redução de minérios de ferro usando hidrogênio e hidrogênio mais monóxido de carbono como redutor para o processo de redução, visando assim à diminuição nas quantidades de CO2 liberadas pelo processo de redução de minérios de ferro. Os minérios foram caracterizados por Microscopia Eletrônica de Varredura, difração de raios-X, quantificação de fases pelo método Rietveld e distribuição granulométrica. Os ensaios de redução foram realizados em balança termogravimétrica e em forno tubular horizontal. A caracterização dos produtos foi realizada usando imagens obtidas por Microscopia Eletrônica de Varredura. Foi constatado que os aumentos da temperatura de redução e do fluxo de gás redutor provocam uma maior degradação física das pelotas. Verificou-se que ocorre a formação de whiskers na superfície externa das pelotas, sendo estes mais frequentes quando do fluxo combinado de H2+CO. Verificou-se que as pelotas reduzidas por hidrogênio puro resultaram em maior porosidade tanto no corpo da pelota ou mesmo no interior das partículas. Foi constatado que ocorre a redução homogênea em todas as partículas componentes da pelota. Foi constatado também que o estudo cinético através dos métodos combinados Jump-FSIA é aplicável na redução direta de pelotas de minério de ferro por H2 e H2+CO. Nas pelotas conformadas a partir de pellet feed com maior área de superfície específica (mais ativas), tanto a cinética quanto a taxa de redução indicaram que a adição de CO ao gás redutor não influi no processo de redução. A teoria de Sestak-Berggren sugere que o mecanismo controlador na reação global é a difusão podendo estar aliado a outras etapas, compondo um mecanismo misto. / The problem of the emission of greenhouse gases is an issue that has gained prominence in recent international conventions. Is added to this question the fact that the steel industry is responsible for a significant portion of emissions of greenhouse gases. The present work aims to study ways of reducing iron ore using hydrogen and hydrogen plus carbon monoxide as a reducing agent to the reduction process, thus aiming to decrease the amounts of CO2 released by reduction of iron ores process. The ores were characterized by Scanning Electron Microscopy, X-ray diffraction, phase quantification by Rietveld method and particle size distribution. The reduction assays were performed in thermogravimetric balance and horizontal tubular oven. The characterization of the products was performed using images obtained by scanning electron microscopy. It was found that increases in temperature and reduction in the flow of reducing gas cause greater physical degradation of the pellets. It was found that the formation of whiskers on the outer surface of the pellets occurs most frequently found when combined flow of H2+CO. It was found that the pellets reduced with pure hydrogen resulted in much higher porosity in the body pellet or even within the particles. It was found that the homogeneous reduction occurs in all components of the particle pellet. It was also found that the kinetic study using the combined methods Jump- FSIA applies in the direct reduction of iron ore pellets by H2 and H2+CO. In shaped pellets from pellet feed with higher specific surface area (more active), both the kinetics as the rate of reduction indicated that the addition of CO to the reducing gas has no effect on the reduction process. The Sestak - Berggren theory suggests that the mechanism controlling the overall reaction is diffusion can be combined with other steps, forming a mixed mechanism.
6

Further Evaluation of Treatments for Vocal Stereotypy: Response Interruption Redirection and Response Cost

McNamara, Kiersty 03 November 2017 (has links)
The purpose of this study was to expand on research by evaluating the effects of response interruption redirection and response cost alone to reduce vocal stereotypy and to evaluate whether response cost increases the effectiveness of response interruption redirection. Treatment phases included response interruption redirection, response cost, and response interruption redirection plus response cost. We saw high rates of vocal stereotypy during baseline, toy baseline, and pre-intervention phases. During all treatment phases, we saw substantial decreases in stereotypy. For two of the three participants response interruption redirection and response cost was a slightly more effective treatment suggesting that using response interruption redirection with an additive of response cost may further suppress stereotypy. These results were replicated across phases. For one participant response interruption redirection was the most effective treatment. All three treatments reduced vocal stereotypy to clinically acceptable levels for two participants. For one participant, there was only a slight decrease in stereotypy when RC was implemented. We discuss limitations and areas for future research.
7

Misophonia: An Investigation of the Lesser-Known Decreased Sound Tolerance Condition

Cusack, Shannon 01 January 2017 (has links)
Misophonia is a decreased sound tolerance condition (DST) that is not yet well-established in the literature. However, the existing research on misophonia shows that it is occurring at substantial levels in the population. The majority of the existing literature has focused on the clinical correlates of misophonia. Although the correlates have been investigated, there is no accepted mechanism behind misophonia etiology or maintenance. The present study examined three hypotheses in order to start to identify potential mechanisms behind misophonia: how emotional predilections are related to the emotional response, how obsessive-compulsive disorder (OCD) symptoms and misophonia are related, and the possibility that the relationship between anxiety sensitivity (AS) and misophonia may be explained in part by the presence of OCD symptoms. Data were collected by Cash (2015) using both undergraduate students (N=451) and community participants (N = 377) using Amazon’s MTurk. Participants completed an online cross-sectional survey assessing for a number of decreased sound tolerance conditions, individual differences variables, and clinical variables. The current study specifically used measures of anxiety sensitivity, OCD, misophonia symptom severity, trait anger, and trait anxiety. Consistent with the literature on state-trait theory, trait emotion was predictive of state levels, such that trait anger was most predictive of an angry misophonic response and trait anxiety was most predictive of an anxious reaction to misophonic stimuli. Misophonia was more strongly related to obsessive than to compulsive components of OCD, consistent with case reports of obsessive thoughts in misophonia. Lastly, OCD symptoms partially mediated the relationship between AS symptom severity and misophonia symptom severity. These results supported our hypotheses, and align with the theorized role of anxiety sensitivity in OCD and in misophonia. Although the data are cross-sectional in nature, and causality cannot be confirmed, the current study provides a strong basis for future research into the mechanisms of misophonia.
8

Analysis of high plasticity clayey soil improvement at subgrade level through Portland cement added to decrease volumetric change

Castro, M., Castro, M., Navarro, J., Aybar, G., Duran, G. 28 February 2020 (has links)
This research includes the potential for resistance and the expansion that the soil presents, this evaluation was carried out through CBR tests. The soil cement technique was used to improve the physical and mechanical characteristics; this process consists in mixing the material with Portland cement type I. That combination forms soil cement 10%, 15% y 20%, which present an increase of the CBR (max: 138.7% and min: 91.9%) achieving a type of extraordinary subgrade to resist the structure of the pavement and a reduction of 7.18% in the expansion of the samples.
9

Atenuação do descenso noturno na predição do início da albuminúria em diabéticos tipo 1

Silva, Bruno Alves January 2018 (has links)
Orientador: Luis Cuadrado Martin / Resumo: A presença de albuminúria constitui fator prognóstico desfavorável nos pacientes diabéticos do tipo 1 e precede a elevação da PA de consultório em três anos. A monitorização ambulatorial de pressão arterial (MAPA) pode identificar a atenuação ou desaparecimento do descenso noturno, o que prediz o risco cardiovascular, independentemente da pressão arterial de 24 h. Entretanto, apenas um estudo avaliou o papel preditivo da atenuação do descenso noturno para o desenvolvimento da albuminúria no diabetes do tipo 1. Assim, o objetivo do corrente trabalho é de avaliar, em coorte brasileira, se o descenso noturno atenuado pode predizer o desenvolvimento de albuminúria no diabetes do tipo 1. Foi realizado estudo observacional prospectivo que visou avaliar o poder preditivo da ausência ou atenuação do descenso noturno em relação ao surgimento de albuminúria em pacientes diabéticos tipo 1 normoalbuminúricos. Os pacientes foram submetidos à MAPA e dosada a albuminúria por mais de 2 vezes. Ao cabo de um ano a albuminúria foi reavaliada. A frequência de evolução para albuminúria ente os pacientes com descenso noturno ausente/atenuado ou presente foi comparada pelo teste de Fisher. As médias de pressão arterial (PA) foram comparadas por teste "t" para amostras independentes. Foi realizada regressão linear para avaliar a associação entre descenso noturno e elevação da albuminúria no seguimento. O nível de significância foi estabelecido em 5 %. Foram avaliados 24 pacientes com idade de 24 ±8,... (Resumo completo, clicar acesso eletrônico abaixo) / Mestre
10

Implementation of operations in double-ended heaps / Implementation of operations in double-ended heaps

Bardiovský, Vojtech January 2012 (has links)
There are several approaches for creating double-ended heaps from the single-ended heaps. We build on one of them, the leaf correspondence heap, to create a generic double ended heap scheme called L-correspondence heap. This will broaden the class of eligible base single-ended heaps (e.g. by Fibonacci heap, Rank-pairing heap) and make the operations Decrease and Increase possible. We show this approach on specific examples for three different single-ended base heaps and give time complexity bounds for all operations. Another result is that for these three examples, the expected amortized time for Decrease and Increase operations in the L-correspondence heap is bounded by a constant.

Page generated in 0.0427 seconds