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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.
71

Extraction of therapeutic proteins from dried blood spots and their analysis on Gyrolab

Garbergs, Hanna January 2011 (has links)
A method for extraction of therapeutic proteins from dried blood spots (DBS) followed by quantification on Gyrolab(TM) has been developed. The method makes it possible to measure the concentration of the analyte in the range 100-6000 ng/mL. The procedure can generate full analytical information from 15 μL blood originally sampled from a subject. The modest sample requirements allows for sampling a full pre-clinical pharmacokinetic profile from a single mouse. This may allow for reduced usage of animals during preclinical development of new therapeutic proteins in accordance with the 3R’s, replace, refine and reduce.
72

Resherch on the segmentation of potential tourist is impression for resorts and the marketing strategies for Moalin national scenic area

Fan, Jue-chin 05 September 2006 (has links)
How potential tourists sort out intriguing resorts or wherever could fulfill their necessities among all the tourism destinations, it¡¦s what tourism marketers eager to know and their intention to guide the tourists. In terms of touristic necessities, besides the general factors such as distance, timing, traffic ways and the cost, tourists would more and more value the image and slant on resorts while choosing tourism destination. They would decide where they want to go by acquiring more information about the credit and image of the resorts, and determine whether they would travel there again by the hands-on traveling experiences and impression. This study has at fist referred to some relevant literatures about the tourists¡¦ impressions and slants on the tourism destination and the segmental marketing, then based on the resources and attributes of Moalin national scenic area to build up measurement and questionnaire for traveling image, so as to carry positive investigation around Taiwan and base on non-residents¡¦ impression for Moalin to segmentalize its potential tourism market. There were totally 900 questionnaires issued and 666 were returned (the valid returning rate was 78%). Then by factor analysis, the images and slants of scenic resorts were divided into four constructs, including ¡§natural landscapes¡¨, ¡§history and culture¡¨, ¡§social environment¡¨ and ¡§agricultural and forestry leisured activity¡¨. Furthermore, the imagery factors of resorts were used to be variables of market segmentation and the potential tourist market was divided into 3 factorial segments as factors of ¡§traveling experiences¡¨, ¡§motives for traveling¡¨ and ¡§cognition on impediments to traveling¡¨. The factors of motives for traveling were especially extracted by factor analysis and ramified into 8 clusters such as factors of ¡§enjoying touring experience¡¨, ¡§molding peaceful temperament¡¨, ¡§calling out friends¡¨, ¡§work-out for health¡¨; as well as the four factors for cognition on impediments to traveling such as ¡§experience and safety¡¨, ¡§travel-mate¡¨, ¡§substantial reasons¡¨ and ¡§environment and equipment¡¨. The author also used traveling images, demographic variables and some relevant data about traveling experiences to describe the characteristic and difference among those market segmentations. In the end, the results were sorted out and described according to the characteristic and difference among those market segmentations, so as to work out suggestions for marketing strategies as reference for relevant industries and tourism agency to choose adequate niche market and efficient market strategy.
73

A method for the characterization of white spots in vacuum-arc remelted superalloys

Viosca, Alan Lee 30 July 2012 (has links)
Vacuum-Arc Remelting (VAR) is an important process for manufacturing Ti- and Ni-based superalloys. Currently, the sources and mechanisms behind microstructural anomalies produced in VAR superalloy ingots are not well understood. In order to help understand formation processes, a method of characterizing specific anomalies in VAR ingots is desired. This paper presents a method of characterizing the composition and morphology of anomalies in VAR alloy ingots using a combination of serial sectioning and X-ray fluorescence (XRF) energy dispersive spectroscopy (EDS) techniques. This process is demonstrated on a dirty white spot from an Alloy 718 sample. The white spot of interest was serial polished and 2-D XRF EDS maps were acquired at each polish depth. The EDS maps were then stacked to form a 3-D representation of the white spot. In addition, SEM and optical microscopy techniques were used to further characterize the composition and morphology of the dirty white spot. The dirty white spot is composed of both Ti-enriched and Nb-depleted regions. The 2-D EDS maps acquired with the XRF equipment provided adequate contrast for creating a 3-D representation of the Ti-rich region of the dirty white spot. However, contrast was not sufficient to create a 3-D representation of the Nb-depleted region. The XRF EDS equipment combined with SEM and optical microscopy techniques provided valuable information about the morphology and composition of the Alloy 718 dirty white spot. It is concluded that this dirty white spot was produced by fall-in from either the crown or shelf regions during the VAR process. / text
74

Ecology of Xanthomonas campestris pv. vitians in relation to development of bacterial leaf spot of lettuce by Vicky Toussaint.

Toussaint, Vicky. January 2001 (has links)
In Quebec, bacterial leaf spot of lettuce was observed for the first time in 1994. Since this first mention, the disease has been observed each year and the severity varied with environmental conditions. Little information was available on this disease because until recently it was only sporadically observed around the world following the first mention in 1918. In this project, we found that two groups of Xanthomonas caused the bacterial leaf spot of lettuce according to the BIOLOG profiles. From the results of strain characterization, a semi-selective medium has been developed to detect and quantify X. campestris pv. vitians. This medium is made of maltose, tryptone, methyl green, phosphate salts, amoxicillin, cephalothin, cycloheximide and trace elements. It allowed us to carry out studies on the ecology of the pathogen and on the disease epidemiology. The effect of weather conditions on bacterial population size and the bacterial leaf spot development has been studied. Weather parameters influencing the bacterial population were the number of hours with temperature higher than 28°C, the number of hours with wind velocity lower than 1 km per hour, the number of hours with relative humidity lower than 45% and the minimum relative humidity. The weather parameters that significantly discriminated between disease increase categories were the mean solar radiation, the number of hours with relative humidity higher than 90%, the mean relative humidity and the maximum temperature. Looking at the relationship between X. campestris pv. vitians population size and host plant development, it was shown that both bacterial population size and disease severity increased with leaf age. Mathematical models were developed to show these relationships. This information will be useful in disease management to decide when to apply bactericides and when to harvest. Finally, an exploratory study was conducted looking at the effects of nutrients on the size of saprophytic bacterial
75

Development and evaluation of procedures and reagents for extraction of proteins from dried blood spots for analysis using Proseek

Björkesten, Johan January 2014 (has links)
A method for extraction of proteins from dried blood spots (DBS) for analysis using Proseek is developed and evaluated. DBS, as sample format, possesses a number of desirable advantages over for example plasma samples. These advantages include for example minimal patient invasiveness, sampling simplicity and non regulated sample transportation. Highly reproducible quantitative detection of 92 proteins is demonstrated from a 1.2 mm in diameter DBS disk. The DBS inter spot analysis precision (7% coefficient of variance) is comparable to plasma inter assay precision (6% coefficient of variance). Coefficient of variance is the ratio between standard deviation to mean value for the analysed replicates. Proseek analysis of DBS could possibly reveal a unique opportunity to examine health related issues in extremely premature infants hopefully resulting in increased survival rates in the future.
76

Exploring crime in Toronto, Ontario with applications for law enforcement planning: Geographic analysis of hot spots and risk factors for expressive and acquisitive crimes

Quick, Matthew January 2013 (has links)
This thesis explores crime hot spots and identifies risk factors of expressive and acquisitive crimes in Toronto, Ontario at the census tract scale using official crime offence data from 2006. Four research objectives motivate this thesis: 1) to understand a number of local spatial cluster detection tests and how they can be applied to inform law enforcement planning and confirmatory research, 2) explore spatial regression techniques and applications in past spatial studies of crime, 3) to examine the influence of social disorganization and non-residential land use on expressive crime at the census tract scale, and 4) integrate social disorganization and routine activity theories to understand the small-area risk factors of acquisitive crimes. Research chapters are thematically linked by an intent to recognize crime as a spatial phenomenon, provide insight into the processes and risk factors associated with crime, and inform efficient and effective law enforcement planning.
77

Population studies of Cercospora zeae-maydis and related Cercospora fungi /

Okori, Patrick, January 2004 (has links) (PDF)
Diss. (sammanfattning). Uppsala : Sveriges lantbruksuniversitet, 2004. / Härtill 4 uppsatser.
78

Recurrent selection for gray leaf spot (GLS) and phaeosphaeria leaf spot (PLS) resistance in four maize populations and heterotic classification of maize germplasm from western Kenya /

Kwena, Philip Onyimbo. January 2007 (has links)
Thesis (Ph.D.) - University of KwaZulu-Natal, Pietermaritzburg, 2007. / Full text also available online. Scroll down for electronic link.
79

Etude expérimentale et numérique des modes de déformation d'un explosif comprimé / Experimental and numerical study of deformation modes of a pressed HMX-based explosive composition

Vial, Jérôme 24 October 2013 (has links)
L’utilisation industrielle ou militaire des explosifs est largement répandue. La sécurité est devenue un axe majeur avec notamment l’ignition involontaire des explosifs composés de HMX lors des impacts à basse vitesse. L’objectif de cette thèse est de contribuer à la compréhension des mécanismes dissipatifs à l’origine des échauffements locaux dans le matériau. Le développement d’un essai aux barres d’Hopkinson a permis de coupler de grandes vitesses de déformations à des pressions élevées pour compléter les données expérimentales. Cet essai a montré un angle de frottement quasiment identique à celui obtenu en quasistatique mais une contrainte de cohésion supérieure d’environ 25 MPa. Ensuite, pour observer les mécanismes pouvant être sources d’échauffement, un essai de compression dans la tranche a été développé avec des observations en temps réel. Celles-ci ont permis de conclure qu’il y a très peu de frottements entre les gros grains et la matrice (l’ensemble des petits grains, du liant et de la porosité). De la plasticité des grains de HMX a pu être observée mais surtout beaucoup d’endommagement dans certaines zones y compris dans la matrice. Une microfissuration très intense de certains grains a été observée. Parallèlement, une représentation numérique biphasique (gros grains de HMX et matrice) de toute la microstructure du matériau a été considérée. Une confrontation entre les observations expérimentales et les simulations a permis de déterminer le seuil de plasticité du HMX. Le comportement de la matrice a été identifié pour prendre en compte l’effet de vitesse et l’endommagement observé. Enfin, les confrontations entre les essais et les simulations de ceux-ci ont montré que les échauffements devraient plutôt se localiser dans la matrice que dans les gros grains de HMX et que le mécanisme le plus probable est le frottement de lèvres de microfissures. / Safety of industrial or military explosives is a major focus to prevent inadvertent ignition due to accidental loading as, for example, low-velocity impact. Our aim is to understand the dissipative mechanisms at work which could heat a pressed HMX-based PBX. A test based on the Split Hopkinson Pressure Bars system is proposed to carry out a dynamic triaxial compression test. This test simultaneously associates a high strain rate and a high pressure. Data have shown almost the same friction angle as during quasi-static experiments, but a higher cohesive stress. Then, A reversed edge-on impact test has been developed. This experiment enables the real-time observation of the deformation mechanisms at the microstructural scale. No relative displacement is observed between the biggest HMX grains and the matrix made of the smallest grains, the binder and the porosity. Plasticity has been observed into some HMX grains as well as damage by microcracking. Meanwhile, a biphasic (HMX grains and matrix) numerical representation of the material microstructure has been considered. A comparison between experimental observations and simulations is used to determine the yield stress of HMX. The behavior of the matrix has been determined to account for the influence of the strain rate and of the damage. Lastly, a comparison between tests and simulations has highlighted (1) that heating should rather be located in the matrix than in the biggest HMX grains and (2) that the most likely heating mechanism is the friction of microcracks lips.
80

Desert Playa Wetlands: Ecological Controls of their Functioning and Responses to Climate Change

January 2016 (has links)
abstract: The Basin and Range province of southwestern USA are composed of different grassland and shrubland ecosystems. Particularly understudied ecosystems in this region are playas, which are ephemerally-flooded wetlands located in topographic low areas of hydrologically-closed dryland catchments. There is not much known about the ecological functioning of playas and the role of playas within desert basins. Even less is known about how global change drivers may affect playas in the future. The main objective of this thesis was to better understand the ecological functioning and the impact of climate change on desert playa wetlands. I collected new data, used existing long-term data, and used simulation modelling techniques to address this objective. I compared playa soils to upland soils and found that playas were hotspots of soil organic carbon and nutrient storage within a desert basin. I also used existing data to analyze the response of above-ground net primary productivity (ANPP) to annual precipitation in playas and upland ecosystems. I found that playa ANPP responded in a non-linear concave-down relationship with annual precipitation amount. Playa ANPP peaked in moderately wet years and declined in very wet years, which was most likely due to flooding; whereas, upland ANPP increased linearly with precipitation. I measured soil organic carbon and nitrogen concentrations in a representative subset of playas and measured the biophysical characteristics of the upland catchments associated with each playa. I found that both catchment geomorphology and vegetation cover were correlated to differences in soil organic carbon and nitrogen among playas. These results showed the importance external soil-inputs delivered via surface runon to playas. Finally, I empirically measured groundwater recharge beneath playas and combined these empirical data with modelling data to forecast how playa groundwater recharge may change in the future. I concluded that playas contribute to groundwater recharge in desert aquifers, playa runon is a strong predictor of playa groundwater recharge, and climate change will have a net-positive impact on groundwater recharge beneath playas. Overall, my thesis research increased the understanding of the role of desert playas on the functioning of dryland ecosystems. / Dissertation/Thesis / Doctoral Dissertation Biology 2016

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