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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.
511

Comparative Mapping of QTLs Affecting Oil Content, Oil Composition, and other Agronomically Important Traits in Oat (Avena sativa L.)

Hizbai, Biniam T. 01 November 2012 (has links)
Groat oil content and composition are important quality traits in oats (Avena sativa L). These traits are controlled by many genes with additive effects. The chromosomal regions containing these genes, known as quantitative trait loci (QTL), can be discovered through their close association with markers. This study investigated total oil content and fatty acid components in an oat breeding population derived from a cross between high oil ('Dal') and low oil ('Exeter') parents. A genetic map consisting of 475 DArT (Diversity Array Technology) markers spanning 1271.8 cM across 40 linkage groups was constructed. QTL analysis for groat oil content and composition was conducted using grain samples grown at Aberdeen, ID in 1997. QTL analysis for multiple agronomic traits was also conducted using data collected from hill plots and field plots in Ottawa, ON in 2010. QTLs for oil content, palmitic acid (16:0), stearic acid (18:0), oleic acid (18:1), linoleic acid (18:2) and linolenic acid (18:3) were identified. Two of the QTLs associated with oil content were also associated with all of the fatty acids examined in this study, and most oil-related QTL showed similar patterns of effect on the fatty acid profile. These results suggest the presence of pleiotropic effects on oil-related traits through influences at specific nodes of the oil synthesis pathway. In addition, 12 QTL-associated markers (likely representing nine unique regions) were associated with plant height, heading date, lodging, and protein content. The results of this study will provide information for molecular breeding as well as insight into the genetic mechanisms controlling oil biosynthesis in oat.
512

高密度ピンアレイ形触覚マウスによる格子状仮想テクスチャ呈示 (第2報,触知ピン間隔,テクスチャ密度および畝高さの検討)

大岡, 昌博, OHKA, Masahiro, 古賀, 浩嗣, KOGA, Hiroshi, 宮岡, 徹, MIYAOKA, Tetsu, 三矢, 保永, MITSUYA, Yasunaga 03 1900 (has links)
No description available.
513

Mikrotypografins inverkan på läsbarheten hos tryckt brödtext : En forskningsöversikt / How microtypography affects the legibility of running text in print : A research review

Skoglund, Gabriel January 2012 (has links)
Hur en texts typografiska utformning påverkar hur enkel den blir att läsa är en fråga som har sysselsatt forskare under lång tid. Förhoppningen har varit att få en bättre förståelse för hur läsning går till och hur man bäst bör sätta text för att underlätta för läsaren. Ett problem har dock varit att skapa medvetenhet om forskningens resultat bland dem som arbetar med att sätta text. Tanken med detta examensarbete var att skapa en överblick av forskningen, med inriktning på hur mikrotypografin, det vill säga den typografi som berör detaljer i textens utformning, påverkar läsbarheten i brödtext. Efter litteratursökningar valdes tio vetenskapligt publicerade empiriska studier på detta område ut. Artiklarna beskrevs och diskuterades med hänsyn till deras metodik och deras resultat. Följande mikrotypografiska faktorer behandlades i studierna: skillnader i läsbarhet mellan typsnitt, x-höjdens och teckenavståndets inverkan på läsbarheten, skillnader i läsbarhet mellan gemener, versaler och kursiv text samt skillnader i läsbarhet mellan olika bokstavsformer. Slutsatsen var att forskningen kring läsbarhet ger intressanta inblickar i hur typografin inverkar på läsprocessen. Det begränsade antalet studier på varje område samt brist på studier utförda på svenska gör det dock svårt att skapa konkreta riktlinjer för hur text bör sättas. Vidare konstaterades att studier utförda i samarbete mellan forskare och typografiskt kunniga vore en möjlig metod att sprida kunskap till de typografiska yrkena och öka sannolikheten för praktisk tillämpning av forskningsresultaten. / How the typographic design of a document affects how easy it is to read is a subject that has long been of interest to researchers. The aim has been to reach a better understanding of the reading process, and to find an ideal way to design text for maximum legibility. However, the researchers have seemingly failed to raise awareness about their results in the typographic community. The aim of this thesis was to create an overview of the research into how microtypography – the typography concerned with individual letters and sentences – affects the legibility of running text. Ten empirical studies on this subject, published in scientific journals, were selected after literature searches. The methods and results of the studies were described and discussed. The studies were concerned with the following microtypographic factors: differences in legibility between typefaces, the role of x-height and letter spacing in, differences in legibility between lower case, upper case and italic letters as well as differences in legibility between specific letter shapes. The conclusion was that legibility research gives interesting insights into how typography can influence the reading process. However, the limited amount of studies found concerning each typographic factor, as well as the lack of studies concerning Swedish typography makes it hard to create typographic guidelines for Swedish typographers based on the research. It was also concluded that studies conducted in cooperation between researchers and typographers might be a way to raise awareness about the research and lead to greater practical application of research results.
514

Klinisches Management des Ullrich-Turner-Syndroms

Schonhoff, Peter 04 April 2012 (has links) (PDF)
In dieser retrospektiven klinischen Studie wurden die Akten von 89 Patientinnen mit Ullrich-Turner-Syndrom ausgewertet, die zwischen 1974 und 2004 in der Universitätsklinik und Poliklinik für Kinder und Jugendliche in Leipzig behandelt worden sind. Berücksichtigt wurde die Verteilung der Karyotypen im Patientenkollektiv sowie das Auftreten von assoziierten Begleiterkrankungen. Das Alter bei Diagnosestellung, die Größe bei Diagnosestellung und die Gründe für die Verdachtsdiagnose Ullrich-Turner-Syndrom wurden analysiert. Darüber hinaus untersuchte der Autor die durchgeführten Maßnahmen zur Pubertätsinduktion im Hinblick auf ihren Beginn und Erfolg sowie deren Einfluss auf die Wachstumraten. Gut 50% der Patientinnen besaßen den Karyotyp 45,X, die anderen Karyotypen setzten sich aus Mosaiken zusammen. Assoziierte Begleiterkrankungen waren im Patientenkollektiv unterrepräsentiert. Das durchschnittliche Alter bei Diagnosestellung betrug 8,21 Jahre, es fiel während des Beobachtungszeitraumes signifikant ab. Der durchschnittliche Größen-SDS zum Zeitpunkt der Diagnosestellung betrug -2,86. Es wurde, verglichen mit den Empfehlungen der Leitlinien, eine verspätete Diagnosestellung konstatiert. Die Pubertätsinduktion begann mit durchschnittlich 13,93 Jahren mit einer signifikanten Reduktion im Verlauf. Die Dauer vom Beginn der Pubertätsinduktion bis zum Eintreten der Menarche betrug 2,51 Jahre, die Dauer vom Tannerstadium B2 zum Stadium B5 betrug gut 27 Monate. Eine Menarche wurde bei nur 65% der Patientinnen sicher beobachtet. Die Ergebnisse wurden kritisch überprüft und in den Kontext anderer Studien eingeordnet. Aus den Ergebnissen wurde gefolgert, dass das Ullrich-Turner-Syndrom, trotz einer positiven Entwicklung in den letzten Jahren, noch immer zu spät diagnostiziert wurde. Die Pubertätsinduktion verlief trotz der verzögerten Diagnosestellung hinsichtlich der Entwicklung der Tannerstadien erfolgreich. Demgegenüber blieb die Induktion der Menarche nur mäßig erfolgreich. Eine Beeinflussung der Wachstumraten durch die Östrogentherapie wurde nicht beobachtet.
515

Obesity and blood pressure among elementary school children in Anadarko Oklahoma

Frick, Lisa Marie, January 2002 (has links) (PDF)
Thesis--University of Oklahoma. / Includes bibliographical references (leaves 75-79).
516

Reservoir description with well-log-based and core-calibrated petrophysical rock classification

Xu, Chicheng 25 September 2013 (has links)
Rock type is a key concept in modern reservoir characterization that straddles multiple scales and bridges multiple disciplines. Reservoir rock classification (or simply rock typing) has been recognized as one of the most effective description tools to facilitate large-scale reservoir modeling and simulation. This dissertation aims to integrate core data and well logs to enhance reservoir description by classifying reservoir rocks in a geologically and petrophysically consistent manner. The main objective is to develop scientific approaches for utilizing multi-physics rock data at different time and length scales to describe reservoir rock-fluid systems. Emphasis is placed on transferring physical understanding of rock types from limited ground-truthing core data to abundant well logs using fast log simulations in a multi-layered earth model. Bimodal log-normal pore-size distribution functions derived from mercury injection capillary pressure (MICP) data are first introduced to characterize complex pore systems in carbonate and tight-gas sandstone reservoirs. Six pore-system attributes are interpreted and integrated to define petrophysical orthogonality or dissimilarity between two pore systems of bimodal log-normal distributions. A simple three-dimensional (3D) cubic pore network model constrained by nuclear magnetic resonance (NMR) and MICP data is developed to quantify fluid distributions and phase connectivity for predicting saturation-dependent relative permeability during two-phase drainage. There is rich petrophysical information in spatial fluid distributions resulting from vertical fluid flow on a geologic time scale and radial mud-filtrate invasion on a drilling time scale. Log attributes elicited by such fluid distributions are captured to quantify dynamic reservoir petrophysical properties and define reservoir flow capacity. A new rock classification workflow that reconciles reservoir saturation-height behavior and mud-filtrate for more accurate dynamic reservoir modeling is developed and verified in both clastic and carbonate fields. Rock types vary and mix at the sub-foot scale in heterogeneous reservoirs due to depositional control or diagenetic overprints. Conventional well logs are limited in their ability to probe the details of each individual bed or rock type as seen from outcrops or cores. A bottom-up Bayesian rock typing method is developed to efficiently test multiple working hypotheses against well logs to quantify uncertainty of rock types and their associated petrophysical properties in thinly bedded reservoirs. Concomitantly, a top-down reservoir description workflow is implemented to characterize intermixed or hybrid rock classes from flow-unit scale (or seismic scale) down to the pore scale based on a multi-scale orthogonal rock class decomposition approach. Correlations between petrophysical rock types and geological facies in reservoirs originating from deltaic and turbidite depositional systems are investigated in detail. Emphasis is placed on the cause-and-effect relationship between pore geometry and rock geological attributes such as grain size and bed thickness. Well log responses to those geological attributes and associated pore geometries are subjected to numerical log simulations. Sensitivity of various physical logs to petrophysical orthogonality between rock classes is investigated to identify the most diagnostic log attributes for log-based rock typing. Field cases of different reservoir types from various geological settings are used to verify the application of petrophysical rock classification to assist reservoir characterization, including facies interpretation, permeability prediction, saturation-height analysis, dynamic petrophysical modeling, uncertainty quantification, petrophysical upscaling, and production forecasting. / text
517

Design, implementation, and characterisation of a novel lidar ceilometer

Vande Hey, Joshua D. January 2013 (has links)
A novel lidar ceilometer prototype based on divided lens optics has been designed, built, characterised, and tested. The primary applications for this manufacturable ground-based sensor are the determination of cloud base height and the measurement of vertical visibility. First, the design, which was developed in order to achieve superior performance at a low cost, is described in detail, along with the process used to develop it. The primary design considerations of optical signal to noise ratio, range-dependent overlap of the transmitter and receiver channels, and manufacturability, were balanced to develop an instrument with good signal to noise ratio, fast turn-on of overlap for detection of close range returns, and a minimised number of optical components and simplicity of assembly for cost control purposes. Second, a novel imaging method for characterisation of transmitter-receiver overlap as a function of range is described and applied to the instrument. The method is validated by an alternative experimental method and a geometric calculation that is specific to the unique geometry of the instrument. These techniques allow the calibration of close range detection sensitivity in order to acquire information prior to full overlap. Finally, signal processing methods used to automate the detection process are described. A novel two-part cloud base detection algorithm has been developed which combines extinction-derived visibility thresholds in the inverted cloud return signal with feature detection on the raw signal. In addition, standard approaches for determination of visibility based on an iterative far boundary inversion method, and calibration of attenuated backscatter profile using returns from a fully-attenuating water cloud, have been applied to the prototype. The prototype design, characterisation, and signal processing have been shown to be appropriate for implementation into a commercial instrument. The work that has been carried out provides a platform upon which a wide range of further work can be built.
518

Relationships between coastal Douglas-fir site index and synoptic categorical measures of site quality

Klinka, Karel, Carter, R. E. (Reid E.), Chourmouzis, Christine January 2001 (has links)
Knowledge of ecological characteristics of trees, sites and tree growth on different sites is fundamental for silvicultural decision-making and planning. With the biogeoclimatic ecosystem classification in place, silvicultural management in British Columbia has been given an ecological foundation; however, relationships between growth and site have not yet been fully investigated. The purpose of this study was to determine how height growth of Douglas-fir within the drier portion of the CWH zone varies with site. We adopted site index (m @ 50 yr bh) as a species-specific measure of forest productivity, recognizing that it indicates height growth performance at a selected point in time. If forest productivity is correlated with ecological measures of site quality, what site factors should be used to quantify the relationships? Because of compensating effects, the numerous site factors can be reduced to four primary (synoptic) factors that directly affect plant establishment and growth: climate (light and temperature), soil moisture, soil nutrients, and soil aeration (not used in this study).
519

Predicting site index of Lodgepole pine and interior spruce in the sub-boreal spruce zone

Klinka, Karel, Wang, Qingli, Wang, G. G., Coates, K. Dave, Chourmouzis, Christine January 2001 (has links)
Knowledge of ecological site characteristics and tree growth on different sites is fundamental for silvicultural decisionmaking and planning. With biogeoclimatic ecosystem classification in place in British Columbia, silvicultural management has been given an ecological foundation; however, relationships between growth and site quality have not yet been fully investigated. The purpose of this study was to determine how site conditions within the SBS zone affect the height growth of lodgepole pine (Pl) and interior spruce (Sx).
520

New height growth and site index models for Pacific silver fir in southwestern British Columbia

Klinka, Karel, Splechtna, Bernhard E., Chourmouzis, Christine, Varga, Pal January 1999 (has links)
Pacific silver fir (Abies amabilis (Dougl. ex Loud.) Forbes) is an important timber crop species in coastal forests of B.C. Its range extends from sea-level to almost timberline, and from the hypermaritime region on the west coast of Vancouver Island to the subcontinental region on the leeward side of the Coast Mountains. With this relatively wide climatic amplitude, a large variability in the height growth pattern of Pacific silver fir can be expected, since climate is considered to be the most influential determinant of the trajectory of height over age of forest trees. This variability, however, is not reflected in the height growth curves and site index tables used to estimate Pacific silver fir site index, since the curves and tables were developed from low-elevation stands on Vancouver Island. Consequently, when these curves and tables are applied to high-elevation or submaritime stands, we get biased estimates of site index. Accurate estimates of site index are necessary for accurate yield predictions. Furthermore, they are essential for making rational decisions about whether to cut the forest in situations where potential tree growth is marginal, such as in high-elevation forests.

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