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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.
231

Identifying Regulatory Patterns at the 3'end Regions of Over-expressed and Under-expressed Genes

Othoum, Ghofran K. 05 1900 (has links)
Promoters, neighboring regulatory regions and those extending further upstream of the 5’end of genes, are considered one of the main components affecting the expression status of genes in a specific phenotype. More recently research by Chen et al. (2006, 2012) and Mapendano et al. (2010) demonstrated that the 3’end regulatory regions of genes also influence gene expression. However, the association between the regulatory regions surrounding 3’end of genes and their over- or under-expression status in a particular phenotype has not been systematically studied. The aim of this study is to ascertain if regulatory regions surrounding the 3’end of genes contain sufficient regulatory information to correlate genes with their expression status in a particular phenotype. Over- and under-expressed ovarian cancer (OC) genes were used as a model. Exploratory analysis of the 3’end regions were performed by transforming the annotated regions using principal component analysis (PCA), followed by clustering the transformed data thereby achieving a clear separation of genes with different expression status. Additionally, several classification algorithms such as Naïve Bayes, Random Forest and Support Vector Machine (SVM) were tested with different parameter settings to analyze the discriminatory capacity of the 3’end regions of genes related to their gene expression status. The best performance was achieved using the SVM classification model with 10-fold cross-validation that yielded an accuracy of 98.4%, sensitivity of 99.5% and specificity of 92.5%. For gene expression status for newly available instances, based on information derived from the 3’end regions, an SVM predictive model was developed with 10-fold cross-validation that yielded an accuracy of 67.0%, sensitivity of 73.2% and specificity of 61.0%. Moreover, building an SVM with polynomial kernel model to PCA transformed data yielded an accuracy of 83.1%, sensitivity of 92.5% and specificity of 74.8% using 10-fold cross-validation for evaluation. These clustering and classification analyses strongly suggest that the regions surrounding the 3’end of genes contain sufficiently rich regulatory information to discriminate between over- and under-expressed genes; at least in the case of genes implicated in OC.
232

Characterising Stream Interaction Regions using 3D magnetohydrodynamic simulations

Pahud, Danielle M. 29 October 2021 (has links)
Throughout the solar cycle and predominantly during the declining phase, Stream Interaction Regions (SIRs) drive space weather on Earth. SIRs occur when the Sun’s rotation aligns a fast solar wind stream behind a slow solar wind stream. Both fast wind and slow wind are compressed and heated, forming a pressure ridge driven by the dynamic pressure of the fast wind. In the frame advecting with the SIR, the high pressure region is bound by a forward wave, which propagates away from the Sun, and reverse wave which propagates sunwards. The pressure waves steepen into shocks with increasing heliospheric distance, the shocks usually form beyond Earth’s orbit. Located between the waves, the stream interface is a tangential discontinuity separating streams that were originally fast from slow. While the general mechanism for the formation and evolution of SIRs is relatively well known, the implications of the 3D structure in the inner heliosphere have not been well understood, in part due to the sparsity of in situ observations outside of the ecliptic plane. In this dissertation, I have used the heliospheric adaptation of the Lyon-Fedder- Mobarry (LFM-helio) MHD model to simulate both idealized and realistic SIR structures in order to validate the model against in situ measurements and to elucidate which characteristics of the solar wind influence the evolution of SIRs. The LFM-helio is shown to accurately reproduce the solar wind conditions at various heliospheric distances. The simulations produced SIRs which agree with in situ observations. The simulations were used to show that the large scale shape of high speed streams driving SIRs affect the amount of heating, compression, and flow deflection. Further, for even small latitudinal separations, SIR evolution depends on the latitudinal structure of the High Speed Stream driving the SIR. Increasing the temperature at the inner boundary of the LFM-helio results in a solar wind that is globally faster and that produces SIRs exhibiting less compressive heating. Increasing the magnetic field strength uniformly at the inner boundary has an effect on the dynamical evolution SIRs whereas increasing the magnetic field strength in proportion to the solar wind speed latitudinally compresses the extent of the band of slow wind, modifying the global structure of the heliosphere.
233

PATTERNS OF DIPEPTIDE USAGE FOR GENE PREDICTION

Gangadharaiah, Dayananda Sagar 16 July 2010 (has links)
No description available.
234

Meridional advection of moisture in the Arctic.

Boyes, G. A. January 1963 (has links)
No description available.
235

A culture in transition : a case study of Eastern Arctic students' creative work

Shapiro, Jane A. (Jane Ann), 1953- January 1989 (has links)
No description available.
236

Paradiplomacia ambiental e econômica no regime internacional de mudanças climáticas : a iniciativa regions adapt

Pinho, Mariângela Mendes Lomba 12 April 2017 (has links)
Submitted by Rosina Valeria Lanzellotti Mattiussi Teixeira (rosina.teixeira@unisantos.br) on 2017-08-15T18:08:30Z No. of bitstreams: 1 Mariangela mendes Lomba Pinho.pdf: 3323000 bytes, checksum: cf5e189449ea8dd8e383ede49e2b7d05 (MD5) / Made available in DSpace on 2017-08-15T18:08:30Z (GMT). No. of bitstreams: 1 Mariangela mendes Lomba Pinho.pdf: 3323000 bytes, checksum: cf5e189449ea8dd8e383ede49e2b7d05 (MD5) Previous issue date: 2017-04-12 / Universidade Católica de Santos - Católica de Santos / Although the International Climate Change Regime has been growing to higher proportions day after day, problems related to global warming seem to have been causing successive losses to mankind; Several initiatives, however, have been implemented towards the mitigation of climate hazards. There is need to go beyond that, though, and take adapting actions to current and future conditions to ensure sustainable development. The State has evidenced its lack of conditions to act efficiently in that segment and that said space is being slowly occupied by subnational players, who become important agents in the international relations. In that context, and considering the capitalist economies in a globalized environment, this thesis analyzes the environmental and economic paradiplomacy as a governance tool to contribute with more effective results, using soft law tools and acting in transnational climate networks, which by means of environmental economic instruments enable project financing. If the adapt is a new path taken in climate-related discussions, an innovative initiative, called Regions Adapt, still in the structuring phase, presents a bold proposal for subnational players. To achieve the outlined goals, this research was initially composed of the bibliographic and documentary method, with a review of the scholarly literature on the topic in general, since specific scientific works have not been found, complemented by technical visits and open interviews. Afterwards, the works was developed on a single case study to test the research compilations. Under such standpoint, São Paulo State was selected, once it holds the economic leadership in the country and because it is the region where this doctoral program is inserted, in addition to the vast experience in several actions already implemented in the international agenda of sustainability. Results indicate that the environmental paradiplomacy and economic paradiplomacy are indispensable tools to help face climate change and foment the new concept of economy, with an array of environmental economic instruments being offered in the market, although, in practical terms, access to the resources is still complex. Researches evidenced that due to the recent installation of the Regions Adapt initiative, economic aspects are not yet outlined. As to the State of São Paulo, object of the single case study, nowadays, despite the difficulties, it presents itself as a pioneer in environmental and paradiplomacy matters. / El Régimen Internacional del Cambio Climático asume proporciones cada vez significativas, pero los problemas relacionados con el calentamiento global siguen causando pérdidas sucesivas en la humanidad. Sin embargo, numerosas iniciativas han sido implementadas para mitigar los riesgos climáticos, pero hay que ir más allá y realizar acciones de adaptación a las condiciones actuales y futuras que pueden asegurar un escenario de desarrollo sostenible. El Estado ha demostrado que no puede actuar con eficacia en este segmento de manera aislada y este espacio ha sido ocupado gradualmente por los actores subnacionales que se convierten en actores importantes en las relaciones internacionales. En este contexto, y teniendo en cuenta las economías capitalistas en un mundo globalizado, esta tesis analiza la paradiplomacia ambiental y económica como herramienta de gobernanza global para contribuir con resultados más eficaces, con el uso de herramientas de soft law y actuando en redes climáticas transnacionales que, a través de instrumentos económicos ambientales, permiten la financiación de proyectos. Si la adaptación es una nueva dimensión en las discusiones de los problemas climáticos, una iniciativa innovadora, llamada Regions Adapt, que aún se está estructurando, se presenta como una propuesta audaz para los actores subnacionales. Para alcanzar los objetivos indicados, el presente tesis consistió en inicialmente adoptar el método bibliográfico y documental, con una revisión de la literatura académica sobre el tema en general, ya que no se encontraron artículos científicos específicos sobre paradiplomacia ambiental y economica, complementados con visitas técnicas y entrevistas abiertas. En la secuencia, se realizó un estudio de caso único para probar la investigación. Bajo este prisma, el Estado de Sao Paulo ha sido elegido, por su liderazgo económico en el país y por ser la región donde se inserta este programa de doctorado y también por su amplia experiencia en diversas acciones ya implementadas en el agenda internacional de la sostenibilidad. Los resultados indican que la paradiplomacia ambiental y económica son herramientas esenciales para ayudar en la lucha contra el cambio climático y promover un nuevo concepto de la economía, ya que se ofrecen en el mercado una amplia gama de instrumentos económicos ambientales, aunque en la práctica el acceso a esos recursos sigue siendo complejo. La investigación demostró que, debido a la reciente instalación de la iniciativa Regions Adapt, todavía sus instrumentos económicos no están bien delineados. En cuanto al Estado de Sao Paulo, estudio de caso único de esta investigación, en nuestros días, a pesar de las dificultades, sigue como pionero en temas ambientales y paradiplomáticos. / O Regime Internacional de Mudanças Climáticas vem tomando proporções cada vez maiores, porém os problemas relacionados ao aquecimento global vêm ocasionando sucessivas perdas à humanidade. Entretanto, inúmeras iniciativas têm sido implementadas no sentido de mitigar os riscos climáticos, mas é preciso ir além e efetuar ações de adaptação para que as condições atuais e futuras possam garantir o desenvolvimento sustentável. O Estado já demonstrou que não apresenta condições de atuar eficientemente neste segmento e este espaço vem sendo ocupado paulatinamente por atores subnacionais, que se tornam importantes agentes nas relações internacionais. Neste contexto, e considerando as economias capitalistas em um ambiente globalizado, a presente tese analisa a paradiplomacia ambiental e econômica como instrumento de governança global para contribuir com resultados mais efetivos, utilizando ferramentas de soft law e atuando em redes climáticas transnacionais que, por meio de instrumentos econômicos ambientais, possibilitam financiamento aos projetos. Se a adaptação é uma nova vertente nas discussões das questões climáticas, uma iniciativa inovadora, denominada Regions Adapt, que ainda está em estruturação, apresenta uma proposta arrojada para os atores subnacionais. Para atingir os objetivos traçados, esta pesquisa compôs-se inicialmente do método bibliográfico e documental, com uma revisão da literatura acadêmica sobre o tema em geral, visto que não foram encontrados trabalhos científicos específicos, complementados por visitas técnicas e entrevistas abertas. Na sequência, efetuou-se um estudo de caso único para testar as compilações da pesquisa. Sob tal prisma, foi selecionado o Estado de São Paulo, por ser a liderança econômica no pais e por ser a região onde este programa de doutorado está inserido, além de possuir vasta experiência em diversas ações já implementadas na agenda internacional da sustentabilidade. Os resultados indicam que a paradiplomacia ambiental e econômica são ferramentas imprescindíveis para auxiliar no enfrentamento das mudanças climáticas e no fomento a um novo conceito de economia, sendo oferecido no mercado uma gama de instrumentos econômicos ambientais, embora na prática o acesso aos recursos ainda seja complexo. As pesquisas evidenciaram que em função da recente instalação da iniciativa Regions Adapt, os aspectos econômicos ainda não estão delineados. Quanto ao Estado de São Paulo, objeto do estudo de caso único, hodiernamente, apesar das dificuldades, apresenta pioneirismo nas questões ambientais e paradiplomáticas.
237

Arid Zone Forestry Program: State of Knowledge and Experience in North America

Ffolliott, Peter F. January 1989 (has links)
No description available.
238

A Distributed Surface Temperature and Energy Balance Model of a Semi-Arid Watershed

Washburne, James Clarke 05 1900 (has links)
A simple model of surface and sub -surface soil temperature was developed at the watershed scale ( -100 km2) in a semi -arid rangeland environment. The model consisted of a linear combination of air temperature and net radiation and assumed: 1) topography controls the spatial distribution of net radiation, 2) near- surface air temperature and incoming solar radiation are relatively homogeneous at the watershed scale and are available from ground stations and 3) soil moisture dominates transient soil thermal property variability. Multiplicative constants were defined to account for clear sky diffuse radiation, soil thermal inertia, an initially fixed ratio between soil heat flux and net radiation and exponential attenuation of solar radiation through a partial canopy. The surface temperature can optionally be adjusted for temperature and emissivity differences between mixed hare soil and vegetation canopies. Model development stressed physical simplicity and commonly available spatial and temporal data sets. Slowly varying surface characteristics, such as albedo, vegetation density and topography were derived from a series of Landsat TM images and a 7.5" USGS digital elevation model at a spatial resolution of 30 m. Diurnally variable atmospheric parameters were derived from a pair of ground meteorological stations using 30 -60 min averages. One site was used to drive the model, the other served as a control to estimate model error. Data collected as part of the Monsoon '90 and WG '92 field experiments over the ARS Walnut Gulch Experimental. Watershed in SE Arizona were used to validate and test the model. Point, transect and spatially distributed values of modeled surface temperature were compared with synchronous ground, aircraft and satellite thermal measurements. There was little difference between ground and aircraft measurements of surface reflectance and temperature which makes aircraft transects the preferred method to "ground truth" satellite observations. Mid- morning modeled surface temperatures were within 2° C of observed values at all but satellite scales, where atmospheric water vapor corrections complicate the determination of accurate temperatures. The utility of satellite thermal measurements and models to study various ground phenomena (eg. soil thermal inertia and surface energy balance) were investigated. Soil moisture anomalies were detectable, but were more likely associated with average near -surface soil moisture levels than individual storm footprints.
239

Forty-five numbers for snow: a brief introduction to the UDC for Polar libraries

Gilbert, Mark, Lane, Heather 12 1900 (has links)
This paper discusses the development of the Polar UDC. It examines some elements of the UDC specific to the Polar context, in particular the geographical auxiliary schedule. Some future plans for the implementation of UDC in a library and also in a museum context are outlined.
240

A distributed surface temperature and energy balance model of a semi-arid watershed.

Washburne, James Clarke. January 1994 (has links)
A simple model of surface and sub-surface soil temperature was developed at the watershed scale (-100 km²) in a semi-arid rangeland environment. The model consisted of a linear combination of air temperature and net radiation and assumed: (1) topography controls the spatial distribution of net radiation, (2) near-surface air temperature and incoming solar radiation are relatively homogeneous at the watershed scale and are available from ground stations and (3) soil moisture dominates transient soil thermal property variability. Multiplicative constants were defined to account for clear sky diffuse radiation, soil thermal inertia, an initially fixed ratio between soil heat flux and net radiation and exponential attenuation of solar radiation through a partial canopy. The surface temperature can optionally be adjusted for temperature and emissivity differences between mixed bare soil and vegetation canopies. Model development stressed physical simplicity and commonly available spatial and temporal data sets. Slowly varying surface characteristics, such as albedo, vegetation density and topography were derived from a series of Landsat TM images and a 7.5" USGS digital elevation model at a spatial resolution of 30 m. Diurnally variable atmospheric parameters were derived from a pair of ground meteorological stations using 30-60 min averages. One site was used to drive the model, the other served as a control to estimate model error. Data collected as part of the Monsoon '90 and WG '92 field experiments over the ARS Walnut Gulch Experimental Watershed in SE Arizona were used to validate and test the model. Point, transect and spatially distributed values of modeled surface temperature were compared with synchronous ground, aircraft and satellite thermal measurements. There was little difference between ground and aircraft measurements of surface reflectance and temperature which makes aircraft transects the preferred method to "ground truth" satellite observations. Mid-morning modeled surface temperatures were within 2° C of observed values at all but satellite scales, where atmospheric water vapor corrections complicate the determination of accurate temperatures. The utility of satellite thermal measurements and models to study various ground phenomena (e.g. soil thermal inertia and surface energy balance) were investigated. Soil moisture anomalies were detectable, but were more likely associated with average near-surface soil moisture levels than individual storm footprints.

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