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Regulation of wool and body growth : nutritional and molecular approachesBray, Megan. January 2002 (has links) (PDF)
"May 2002" Includes bibliographical references (leaves 148-164) Describes a series of novel experiments designed to enhance our understanding of nutrient utilisation for growth of wool and the whole body.
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Regulation of wool and body growth : nutritional and molecular approaches / Megan Bray.Bray, Megan January 2002 (has links)
"May 2002" / Includes bibliographical references (leaves 148-164) / xi, 164 leaves : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Describes a series of novel experiments designed to enhance our understanding of nutrient utilisation for growth of wool and the whole body. / Thesis (Ph.D.)--University of Adelaide, Dept. of Animal Science, 2002
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The effect of depth of placement of phosphorus fertiliser on the growth and development of field peasDerafshi, Mohammadali H. January 1997 (has links) (PDF)
Bibliography: leaves 190-212. This thesis reports on the results of 3 glasshouse and 3 field experiments. The glasshouse experiments measure the effects of depth of placement and level of phosphorus (P) on the growth of field peas (Pisum sativum L. cv. Alma). The results of all the experiments suggest that placing P fertiliser 4-5 cm below the seed of field pea crops will be beneficial in terms of nodulation, P uptake, grain yield and grain P concentration.
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Field study of competition between medusahead (Taeniatherum caput-medusae ssp. asperum (Simk.) Melderis) and squirreltail (Elymus elymoides (Raf.) Swezey)Clausnitzer, David 15 August 1996 (has links)
Medusahead (Taeniatherum caput-medusae ssp. asperum (Simk.) Melderis) is a Eurasian annual grass that infests large areas of U.S. rangelands, dominating former bunchgrass/shrub sites. Squirreltail (Elymus elymoides (Raf.) Swezey) is a native perennial grass that has demonstrated the ability to establish in stands of medusahead.
A study conducted on two sites near Burns, OR had the objectives of quantifying competition between medusahead and squirreltail, and determining the effect of moisture availability on competition. Two hundred plots were arranged in a factorial design. Measurements were taken of plant growth, seed production, soil moisture, and climate.
Results for the two years are contrasting. The first year was very dry. Medusahead grew and reproduced well, producing a seed crop up to 10 times the amount planted; squirreltail grew poorly and did not reproduce. Samples of squirreltail seed retrieved from the plots in late summer were found to have remained dormant since seeding. The second year had above-average precipitation. Medusahead grew and
reproduced well again. Squirreltail grew and reproduced abundantly on one of the sites, both on freshly-seeded plots and on plots containing dormant seeds and surviving plants from the previous year.
In all cases, medusahead exhibited stronger interspecific and intraspecific
competitive effects than did squirreltail seedlings. With adequate soil moisture,
squirreltail reduced average weight and median seed production of individual medusahead
plants, but did not reduce medusahead seed production per square meter. Medusahead
succeeded in a drought year by utilizing deep soil moisture, and utilized shallower moisture in a wet year. During a wet year in plots containing mature squirreltail, medusahead utilized shallower moisture, while squirreltail strongly utilized much deeper
moisture. Interspecific competitive interference by medusahead on squirreltail seedlings suggests the potential benefits of suppressing medusahead during the seeding year for squirreltail in a rehabilitation effort, especially if climatic conditions are conducive to squirreltail germination and establishment. / Graduation date: 1997
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A New Screening Methodology for Mixture ExperimentsWeese, Maria 01 May 2010 (has links)
Many materials we use in daily life are comprised of a mixture; plastics, gasoline, food, medicine, etc. Mixture experiments, where factors are proportions of components and the response depends only on the relative proportions of the components, are an integral part of product development and improvement. However, when the number of components is large and there are complex constraints, experimentation can be a daunting task. We study screening methods in a mixture setting using the framework of the Cox mixture model [1]. We exploit the easy interpretation of the parameters in the Cox mixture model and develop methods for screening in a mixture setting. We present specific methods for adding a component, removing a component and a general method for screening a subset of components in mixtures with complex constraints. The variances of our parameter estimates are comparable with the typically used Scheff ́e model variances and our methods provide a reduced run size for screening experiments with mixtures containing a large number of components. We then further extend the new screening methods by using Evolutionary Operation (EVOP) developed by Box and Draper [2]. EVOP methods use small movement in a subset of process parameters and replication to reveal effects out of the process noise. Mixture experiments inherently have small movements (since the proportions can only range from zero to unity) and the effects have large variances. We update the EVOP methods by using sequential testing of effects opposed to the confidence interval method originally proposed by Box and Draper. We show that the sequential testing approach as compared with a fixed sample size reduced the required sample size as much as 50 percent with all other testing parameters held constant. We present two methods for adding a component and a general screening method using a graphical sequential t-test and provide R-code to reproduce the limits for the test.
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Computer and physical experiments: design, modeling, and multivariate interpolationKang, Lulu 28 June 2010 (has links)
Many problems in science and engineering are solved through experimental investigations. Because experiments can be costly and time consuming, it is important to efficiently design the experiment so that maximum information about the problem can be obtained. It is also important to devise efficient statistical methods to analyze the experimental data so that none of the information is lost. This thesis makes contributions on several aspects in the field of design and analysis of experiments. It consists of two parts. The first part focuses on physical experiments, and the second part on computer experiments.
The first part on physical experiments contains three works. The first work develops Bayesian experimental designs for robustness studies, which can be applied in industries for quality improvement. The existing methods rely on modifying effect hierarchy principle to give more importance to control-by-noise interactions, which can violate the true effect order of a system because the order should not depend on the objective of an experiment. The proposed Bayesian approach uses a prior distribution to capture the effect hierarchy property and then uses an optimal design criterion to satisfy the robustness objectives. The second work extends the above Bayesian approach to blocked experimental designs. The third work proposes a new modeling and design strategy for mixture-of-mixtures experiments and applies it in the optimization of Pringles potato crisps. The proposed model substantially reduces the number of parameters in the existing multiple-Scheffé model and thus, helps the engineers to design much smaller experiments.
The second part on computer experiments introduces two new methods for analyzing the data. The first is an interpolation method called regression-based inverse distance weighting (RIDW) method, which is shown to overcome some of the computational and numerical problems associated with kriging, particularly in dealing with large data and/or high dimensional problems. In the second work, we introduce a general nonparametric regression method, called kernel sum regression. More importantly, we make an interesting discovery by showing that a particular form of this regression method becomes an interpolation method, which can be used to analyze computer experiments with deterministic outputs.
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Thermodynamic investigations of some aqueous solutions through calorimetry and densimetryMarriott, Robert A., University of Lethbridge. Faculty of Arts and Science January 1999 (has links)
Relative densities and heat capacity ratios have been measured for selected aqueous systems. These measurements have been used to calculate apparent molar volumes and heat capacities. Densities of aqueous sodium bromide have been measured from 374 to 522 K and 10.00 to 30.00 MPa using a recently developed high temperature and pressure vibrating tube densimeter. These data have been used to test the utility of an automated high temperature and pressure densimetric data analysis program. Apparent molar volumes and heat capacities of several aqueous rare earth sulphate systems at 298.15 K and 0.10 MPa have been reported, and discussed in terms of ionic contributions. Single ion partial molar volumes and heat capacities for aqueous trivalent rare earth species have been estimated in a review of apparent molar data from the literature and through the use of semi-empirical Debye-Huckel equation. These singles ion properties have subsequently
been used to estimate the single ion properties of the monosulphate and disulphate rare earth complex species. Rigorous relaxation calculations are presented in a discussion of apparent molar heat capacities,
where relaxation contributions are shown to be negative. Apparent molar volumes and densities for aqueous L-histidine, L-phenylalanine, L-tyrosine, L-tryptophan, and L-dopa have been used to estimate reported
partial molar properties have been added to several reported properites for other amino acids and peptides to construct an additivity scheme that utilises the revised Helgeson, Kirkham, and Flowers (HKF) equations of state for neutral organic species. A volumetric study of aqueous glycine, L-serine, and glyclylglycine has been conducted at temperatures from 298 K to 423 K and pressures from 0.10 to 30.00 MPa. These data have been used to evaluate HKF coefficients in a discussion of peptide stability at elevated temperatures and pressures. / xvii, 220 leaves : ill. ; 28 cm.
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On the external validity of laboratory experimentsBoly, Amadou January 2009 (has links)
Thèse numérisée par la Division de la gestion de documents et des archives de l'Université de Montréal
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The effect of depth of placement of phosphorus fertiliser on the growth and development of field peas / by Mohammadali H. Derafshi.Derafshi, Mohammadali H. January 1997 (has links)
Bibliography: leaves 190-212. / xii, 212 leaves : ill. (some col.) ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / This thesis reports on the results of 3 glasshouse and 3 field experiments. The glasshouse experiments measure the effects of depth of placement and level of phosphorus (P) on the growth of field peas (Pisum sativum L. cv. Alma). The results of all the experiments suggest that placing P fertiliser 4-5 cm below the seed of field pea crops will be beneficial in terms of nodulation, P uptake, grain yield and grain P concentration. / Thesis (Ph.D.)--University of Adelaide, Dept. of Agronomy and Farming Systems, 1997
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The effect of depth of placement of phosphorus fertiliser on the growth and development of field peas / by Mohammadali H. Derafshi.Derafshi, Mohammadali H. January 1997 (has links)
Bibliography: leaves 190-212. / xii, 212 leaves : ill. (some col.) ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / This thesis reports on the results of 3 glasshouse and 3 field experiments. The glasshouse experiments measure the effects of depth of placement and level of phosphorus (P) on the growth of field peas (Pisum sativum L. cv. Alma). The results of all the experiments suggest that placing P fertiliser 4-5 cm below the seed of field pea crops will be beneficial in terms of nodulation, P uptake, grain yield and grain P concentration. / Thesis (Ph.D.)--University of Adelaide, Dept. of Agronomy and Farming Systems, 1997
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