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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

Morphological granulometric estimation with random primitives and applications to blood cell counting

Theera-Umpon, Nipon, January 2000 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 2000. / Typescript. Vita. Includes bibliographical references (leaves 113-117). Also available on the Internet.
132

Leukocyte activation in newborns in relation to prenatal stress

Yektaei-Karin, Elham, January 2009 (has links)
Diss. (sammanfattning) Stockholm : Karolinska institutet, 2009. / Härtill 4 uppsatser.
133

Morphological granulometric estimation with random primitives and applications to blood cell counting /

Theera-Umpon, Nipon, January 2000 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 2000. / Typescript. Vita. Includes bibliographical references (leaves 113-117). Also available on the Internet.
134

Hämatologisch-immunologische Verlaufsuntersuchungen bei Kühen mit Gebärparese

Winkler, Katharina Regina 11 June 2015 (has links) (PDF)
Zusammenfassung Katharina Regina Winkler Hämatologisch-immunologische Verlaufsuntersuchungen bei Kühen mit Gebärparese Medizinische Tierklinik der Veterinärmedizinischen Fakultät der Universität Leipzig Eingereicht im September 2014 100 Seiten, 41 Abbildungen, 13 Tabellen, 282 Literaturangaben, 17 Seiten Anhang Schlüsselwörter: Gebärparese, Stoffwechsel, Glucocorticoide, Endotoxin, Blutbild Problemstellung: Der Mineralstoffwechsel unterliegt immunologischen Einflüssen. Vitamin-D3 ist essentiell für die Antigen- und Zytokinsynthesen in den Blutzellen. Die Osteoblastenreifung wird durch Zytokine beeinflusst. Das tangiert die Gebärparese (GP) und erschließt potentiell prophylaktische sowie therapeutische Ansätze. Zielstellung: Es wurde geprüft, ob a) es Mineralstoffunterschiede bei der GP-Diagnose und im Verlauf zu früheren Studien gibt, b) die Parameter Endotoxin (ET), anti-Lipid A-IgG-Titer (ALA-IgG-Titer) und Haptoglobin (Hp) sowie Leuko- und Erythrogramme gesicherte Beziehungen zur GP sowie zu Mineralstoffen und immunologischen Parametern haben, c) die Therapie bei GP durch Glucocorticoide verbessert werden kann und d) Jungkühe mehr Geburtsstress und Belastungen des Ca-Pi-K-Stoffwechsels haben. Versuchsanordnung: Untersucht wurden 111 HF-Kühe bzw. Jungkühe: 21 GP-Kühe mit Grundbehandlung, 22 GP-Kühe mit zusätzlicher Dexamethason-21-iso-ni-cotinat-Therapie (Dexa-IN), 40 gesunde Kontrollkühe (KG) und 28 gesunde Jungkühe. Laborkontrollen erfolgten bei den GP-Kühen vor der Therapie, bei den KG 1 - 3 Tage post partum (d p. p.) sowie 1 d und 14 d nach dem Therapiedatum. Analysiert wurden neben Stoffwechselparametern Endotoxin (LAL-Test), ALA-IgG-Titer, Haptoglobin sowie das Leuko- und Erythrogramm. Ergebnisse: Die Erstbehandlung war bei 47 % ohne und 67 % mit Dexa-IN-Therapie erfolgreich; die Heilungsrate betrug 74 bzw. 82 %, d. h., die Dexa-IN-Therapie verbesserte das Behandlungsergebnis bei GP ohne Nebenwirkungen. 69,8 % der GP-Kühe hatten eine kombinierte Hypokalz- und Hypophosphatämie. 24 Stunden nach Beginn der Therapie waren beide Mineralstoffe in den GP-Gruppen wieder physiologisch. 11,6 % der GP-Kühe und 10,7 % der Jungkühe hatten eine Hypophosphatämie. Das ist offensichtlich eine Folge des Kalbestresses in diesen Gruppen. Die Mg-, Na- und Cl-Konzentrationen waren in allen Gruppen physiologisch. Mg korrelierte negativ mit Ca und Pi (p<0,01). Die K-Konzentrationen waren in den GP-Gruppen einen d p. p. signifikant niedriger als in den KG. Sie korrelierten mit Ca- und Pi in den GP-Gruppen mit 0,42 bis 0,48 (p<0,01). Auf stärkere Stresseinflüsse auf K wiesen Korrelationen zu Glucose, Bilirubin, eosinophile und basophile Granulozyten sowie Lymphozyten hin. Die Fe-Konzentrationen der GP- und KG-Kühe waren physiologisch. Fe korrelierte mit ALA-IgG-Titer gesichert negativ. Die ET-Konzentrationen ließen nur schwache Beziehungen zur GP erkennen, wie rET:Ca=-0,17 (p<0,05). ET korrelierte mit den ALA-IgG-Titern gesichert positiv (Dexa-IN-Gruppe). Die ALA-IgG-Titer differierten bei den Kühen nicht gesichert, sie korrelierten nicht mit Ca, aber mit Pi und mit der Mehrzahl der klinisch-chemischen und hämatologischen Parameter. Das zeigt die Entzündungseinflüsse auf den Pi-Stoffwechsel mit der Förderung von Hypophosphatämien. Die Hp-Konzentrationen streuten stark und waren in allen Gruppen am Diagnose- und noch mehr am Folgetag erhöht (p>0,05). Bei Jungkühen wies der höhere Anstieg auf stärkeren Kalbestress hin. Die Leukozytenzahl war am GP-Diagnosetag erhöht (Leukozytose; p>0,05) und sank zum Folgetag in den Normbereich ab. In der Dexa-IN-Gruppe war der Abfall am stärksten (p<0,05). Die Leukozytenzahl korrelierte gesichert negativ mit den ALA-IgG-Titer sowie in den GP-Gruppen mit den Pi- sowie Ca-Konzentrationen, ebenso die neutrophilen Granulozyten. Eosinophile, basophile Granulozyten sowie Lymphozyten sanken p. p. ab (p<0,05) und korrelierten gesichert mit Ca und Pi. Die GP-Kühe hatten am Diagnosetag eine Monozytose (p<0,05). Die Monozyten korrelierten mit den ALA-IgG-Titern, mit dem Pi und dem Ca gesichert negativ. Sie hatten die engsten Beziehungen zum Entzündungsgeschehen sowie den Pi- und Ca-Konzentrationen. Die CK-Aktivitäten waren am Diagnose- und am Folgetag gegenüber der KG signifikant erhöht. Mit Ca korrelierte die CK in allen Kuh-Gruppen gesichert negativ, mit Pi nur in der GP-Gruppe ohne Dexa-IN. Die CK stand in enger gesicherter Beziehung zu Entzündungsindikatoren. Hämoglobin war in den GP-Gruppen am Diagnosetag signifikant, der Hämatokrit und die Erythrozytenzahlen tendenziell gesteigert. Schlussfolgerungen: Die Studie zeigt bei GP-Kühen vielfältige Beziehungen des Ca-Pi-K-Stoffwechsels zu Entzündungsindikatoren und legt ursächliche Einflüsse nahe, besonders zu ALA-IgG-Titern und Monozyten. Sie können Ursachen für Hypophosphat- und Hypokalämie sein. Zusätzliche Dexa-IN-Therapie verbessert das Behandlungsergebnis.
135

Automated Quantification of Biological Microstructures Using Unbiased Stereology

Bonam, Om Pavithra 01 January 2011 (has links)
Research in many fields of life and biomedical sciences depends on the microscopic image analysis of biological images. Quantitative analysis of these images is often time-consuming, tedious, and may be prone to subjective bias from the observer and inter /intra observer variations. Systems for automatic analysis developed in the past decade determine various parameters associated with biological tissue, such as the number of cells, object volume and length of fibers to avoid problems with manual collection of microscopic data. Specifically, automatic analysis of biological microstructures using unbiased stereology, a set of approaches designed to avoid all known sources of systematic error, plays a large and growing role in bioscience research. Our aim is to develop an algorithm that automates and increases the throughput of a commercially available, computerized stereology device (Stereologer, Stereology Resource Center, Chester, MD). The current method for estimation of first and second order parameters of biological microstructures requires a trained user to manually select biological objects of interest (cells, fibers etc.) while systematically stepping through the three dimensional volume of a stained tissue section. The present research proposes a three-part method to automate the above process: detect the objects, connect the objects through a z-stack of images (images at varying focal planes) to form a 3D object and finally count the 3D objects. The first step involves detection of objects through learned thresholding or automatic thresholding. Learned thresholding identifies the objects of interest by training on images to obtain the threshold range for objects of interest. Automatic thresholding is performed on gray level images converted from RGB (red-green-blue) microscopic images to detect the objects of interest. Both learned and automatic thresholding are followed by iterative thresholding to separate objects that are close to each other. The second step, linking objects through a z-stack of images involves labeling the objects of interest using connected component analysis and then connecting these labeled objects across the stack of images to produce a 3D object. Finally, the number of linked objects in a 3D volume is counted using the counting rules of stereology. This automatic approach achieves an overall object detection rate of 74%. Thus, these results support the view that automatic image analysis combined with unbiased sampling as well as assumption and model-free geometric probes, provides accurate and efficient quantification of biological objects.
136

Physical Activity Promotion among School-Aged Children Using Pedometers and Rewards

Ek, Kari E 01 January 2011 (has links)
Physical activity is important for children as many children are considered overweight or obese. The benefits of exercise have been demonstrated in empirical studies across all age ranges (Horne, Hardman, Lowe, & Rowlands, 2009; Kelly et al., 2004; Louie & Chan, 2003; Southard & Southard, 2006). In the current study, a multiple baseline design across participants was used to assess the effectiveness of goal setting, reinforcement contingencies, and pedometers that provide feedback to increase step count of 5 participants. During baseline each participant wore a sealed pedometer to assess the average steps the participants took per day. After baseline, each participant, researcher, and parent set a reasonable goal of steps to achieve per day in order to receive a specific reinforcer chosen by the parent and participant. A behavioral contract stated the specific goal number of steps for the day and the specific reinforcer they would receive. At the end of each day before the child went to bed, the parent recorded the number of steps and provided the child with feedback about whether reinforcement was earned. Data collection for four of the five participants showed a mean increase in steps taken per day during intervention 1 in comparison to baseline levels. Participants met their goal step counts during intervention 1 on 12%, 35%, 50%, 71% and 76% of days. All three participants that participated in intervention 2 increased their mean count from both baseline and intervention 1 levels. Participants met their goal step counts during intervention 2 on 62%, 100%, and 100% of days. Two participants participated in the follow up phase of the study; both participants maintained their goals from intervention 2 and completed their goal step count on 100% of days.
137

On modeling telecommuting behavior : option, choice and frequency

Singh, Palvinder 18 June 2012 (has links)
The current study contributes to the already substantial scholarly literature on telecommuting by estimating a joint model of three dimensions- option, choice and frequency of telecommuting. In doing so, we focus on workers who are not self-employed workers and who have a primary work place that is outside their homes. The unique methodological features of this study include the use of a general and flexible generalized hurdle count model to analyze the precise count of telecommuting days per month, and the formulation and estimation of a model system that embeds the count model within a larger multivariate choice framework. The unique substantive aspects of this study include the consideration of the "option to telecommute" dimension and the consideration of a host of residential neighborhood built environment variables. The 2009 NHTS data is used for the analysis, and allows us to develop a current perspective of the process driving telecommuting decisions. This data set is supplemented with a built environment data base to capture the effects of demographic, work-related, and built environment measures on the telecommuting-related dimensions. In addition to providing important insights for policy analysis, the results in this study indicate that ignoring the "option" dimension of telecommuting can, and generally will, lead to incorrect conclusions regarding the behavioral processes governing telecommuting decisions. The empirical results have implications for transportation planning analysis as well as for the worker recruitment/retention and productivity literature. / text
138

A count data model with endogenous covariates : formulation and application to roadway crash frequency at intersections

Born, Kathryn Mary 24 March 2014 (has links)
This thesis proposes an estimation approach for count data models with endogenous covariates. The maximum approximate composite marginal likelihood inference approach is used to estimate model parameters. The modeling framework is applied to predict crash frequency at urban intersections in Irving, Texas. The sample is drawn from the Texas Department of Transportation crash incident files for the year 2008. The results highlight the importance of accommodating endogeneity effects in count models. In addition, the results reveal the increased propensity for crashes at intersections with flashing lights, intersections with crest approaches, and intersections that are on frontage roads. / text
139

A framework for developing road risk indices using quantile regression based crash prediction model

Wu, Hui, doctor of civil engineering 13 October 2011 (has links)
Safety reviews of existing roads are becoming a popular practice of many agencies nationally and internationally. Knowing road safety information is of great importance to both policymakers in addressing safety concerns and travelers in managing their trips. There have been various efforts in developing methodologies to measure and assess road safety in an effective manner. However, the existing research and practices are still constrained by their subjective and reactive nature. The goal of this research is to develop a framework of Road Risk Indices (RRIs) to assess road risks of existing highway infrastructure for both road users and agencies based on road geometrics, traffic conditions, and historical crash data. The proposed RRIs are intended to give a comprehensive and objective view of road safety, so that safety problems can be identified at an early stage before they rise in the form of accidents. A methodological framework of formulating RRIs that integrates results from crash prediction models and historical crash data is proposed, and Linear Referencing tools in the ArcGIS software are used to develop digital maps to publish estimated RRIs. These maps provide basic Geographic Information System (GIS) functions, including viewing and querying RRIs, and performing spatial analysis tasks. A semi-parameter count model and quantile regression based estimation are proposed to capture the specific characteristics of crash data and provide more robust and accurate predictions on crash counts. Crash data collected on Interstate Highways in Washington State for the year 2002 was extracted from the Highway Safety Information System (HSIS) and used for the case study. The results from the case study show that the proposed framework is capable of capturing statistical correlations between traffic crashes and influencing factors, leading to the effective integration of safety information in composite indices. / text
140

Characterization of the spatial arrangement of opening-mode fractures

Gómez Torres, Leonel Augusto, 1969- 07 November 2011 (has links)
In spite of the abundance of opening-mode fractures in the earth's upper crust, knowledge about their spatial arrangement remains limited. The spatial arrangement of fractures refers to the patterns of fracture positions in space. On one-dimensional analyses, fracture position can be obtained by combining fracture apertures, spacings, and their sequence along a one-dimensional scanline. Previous approaches failed to account for fracture position and fracture size, thus a new technique, normalized correlation count (NCC), was used to overcome these limitations. This technique was designed to distinguish random from non-random (fractal, inherited/imposed, periodically arranged fractures, or periodically arranged clusters) spatial arrangements of fractures. In addition, another method to quantify the attributes of microfractures in rock samples larger than a thin section was developed and used to quantify their spatial arrangements. NCC indicated that where statistically significant (non-random) clusters exist, large fractures are more clustered than small ones. Differential clustering according to fracture size was detected in data sets from different lithologies at outcrop and rock-sample scale, suggesting that this phenomenon is related to development of fracture systems as opposed to host rock lithology and scale. Fracture clusters with power-law variation of spatial correlation with length scale are not strictly natural fractals because clusters occur in cascades at discrete values of length scale and not in a continuous fashion. Some statistically significant clusters with a power-law of spatial correlation are formed by smaller clusters with a power-law of spatial correlation that are also periodically arranged. Fractures from the Cupido Fm. in the Monterrey salient were grouped in three categories based on their trace morphology, cement composition, and timing of fracture cements with respect to fracture opening. Fractures at outcrop scale in two of the categories exhibit low percentages of synkinematic cement and random arrangements, whereas fractures in the remaining category exhibit large amounts of synkinematic cement and periodically arranged clusters. An evolutionary model of fracture development based on subcritical propagation is proposed. This model suggests that mechanical layering increases during cluster development, explaining the non-random clustering within interclustering domains at outcrop scale and implies that cluster spacing increases with mechanical layering but decreases during evolution towards cluster saturation. / text

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