Thesis (Ph. D.)--West Virginia University, 2003. / Title from document title page. Document formatted into pages; contains xiii, 122 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 100-106).

The first objective of this study was to evaluate the utility of bulk tank tests to detect the presence of Mycobacterium avium subspecies paratuberculosis (MAP) antibody in dairy herds for the purpose of Johne’s disease surveillance. Individual cow milk samples were collected by CanWest Dairy Herd Improvement customer service representatives in herds across Ontario, Canada. These samples, along with bronopol preserved bulk tank samples were collected from herds participating in the Ontario Johne’s Education and Management Assistance Program (OJEMAP), a producer funded Johne’s control scheme. Overall, there were 309 farms tested, with herd size from 15 to 986 milking cows. The relative sensitivity and specificity of the bulk tank ELISA test when a positive herd was defined as 1 or more positive cows was 54.7% and 90.6%, respectively. The second objective was to determine the effect of milk storage temperature and duration on the Johne’s milk ELISA test result. When herd level factors were considered in a logistic model, average monthly protein (%) and the percent of positive milk contributed to the bulk tank by milk ELISA positive cows were found to be significantly (p<0.05) associated with the probability of a herd testing positive on the bulk tank Hyper ELISA protocol. Positive and negative MAP milk samples were stored for varying times and under different temperature conditions. In a mixed linear model, time was found to be significantly (<0.001) associated with the log transformed ELISA optical density. When the results were dichotomized into positive and negative by the cut-off of 0.10 and cross classified, the amount of misclassification was considered biologically negligible.

Thesis (doctoral)--Universität Bonn, 1990. / Vita. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (p. 179-184).

Thesis (doctoral)--Universität Bonn, 1990. / Vita. Includes bibliographical references (p. 179-184).

Forces acting between individual grains in a powder can have a critical and controlling effect on powder bulk behaviour. Operations such as powder flow, fluidisation, compaction, agglomeration and mixing are all influenced significantly by the intensity of interparticle forces. This is especially true when the particle size falls below around 100 mum at which point the surface forces outweigh the force due to gravity acting on a single particle. Studies of cohesion using bulk powder samples are of limited use because it is difficult to decouple the fundamental mechanisms of interparticle force from other contributions to cohesion such as variations in the powder microstructure, or geometric interlocking of individual particles. A review of the relevant literature has unearthed conflicting evidence associated with the influence of relative humidity (RH) on both bulk powder cohesion and interparticle force. Therefore there is a need for experimental force studies at the scale of the individual particle to identify the fundamental mechanisms that prevail and resolve some of the apparent uncertainty that currently exists. A custom built force instrument, incorporating Atomic Force Microscope (AFM) technology, was designed, constructed and commissioned. This instrument was used to quantify the interactions between particles of around 40 mum in diameter and flat surfaces as a function of the relative humidity of the surrounding air. Interactions between soda-lime glass surfaces, gold surfaces and amorphous quartz surfaces were studied. Striking results were obtained on soda-lime glass surfaces upon decreasing the RH from > 70% to around 40%. At this point the glass surfaces suddenly exhibited a strong repulsion upon approach. The range of this repulsion was observed at separation distances as great as 250 nm. Once the surfaces were brought into contact the strong repulsion was accompanied by a very large force of adhesion. This strong repulsion and associated peak value of adhesion was not observed at other RH values and was specific to desorption rather than adsorption. Force curves for gold and quartz surfaces showed no such repulsion and peak adhesion. It is thought that the critical humidity coincides with the formation of a complete monolayer of adsorbed water molecules. A number of possible explanations have been offered for the effect and its uniqueness to soda-lime glass in the present experiments. Theoretical calculations of adhesion force have been performed based on the concept of capillary meniscus formation. Calculations give values of around 17000 nN for a sphere 40 mum in diameter and a contact angle of 20&deg;. These values are somewhat larger than measured values in all cases apart from peak adhesion. It is thought that at low humidities there is insufficient water adsorbed to overcome the effect of surface roughness. Contact occurs at asperities, which reduces the expected contact area and hence leads to an adhesive force that is lower than predicted. At humidities > 80% the experiments show evidence of capillary elongation upon surface separation. This implies that the surface adsorbed film is mobile with bulk liquid being drawn into the bridge under the action of the surface tension force. The associated increase in bridge volume and the change in bridge curvature with I elongation will tend to equalise the Laplace pressure inside the bridge and therefore give a value of adhesion that is lower than predicted.

Since, June of 1999 The Regulation of Bulk Transfer for Urban Planning has been carried out, which is tried implementing in Taipei & Taipei county until June of 2004. From July 1 of 2005, on all counties and cities implement it in an all-round way. So far, there are only two application cases in Kaohsiung city , since the examining principles have been announced. This research will probe into reference documents of TDR and all the situtations about bulk transfer in this country¡CThrough all these points of view the study aims at probing into the problems of implementing it in Kaohsiung city bulk transfer.The research approach adopts an exploratory case study, including calculating IRR with cases and interviewing real estate, officials and scholars. The goal is to get ¡§generalizing¡¨ , not ¡§ particularizing¡¨ analysis.The result of study is based on construct validity of thesis. It¡¦s analytic generalization not statistical generalization.From the sight of Kaohsiung¡¦s TOD policy we find :In policy direction, for core of the city (Cianjin, Sinsing, Lingya, Sanmin, Yencheng district), there are functions to match up the centeral government¡¦s six years plan for urban renewal.But urban renewal is the most difficult for real estate co. to invest and develop.Nowadays, outside the core of city and in the suburb, vacan lots are preferred to invest.Like this, the policy directions are not combined with the behavior of non-governmental investment.The bulk is needed in the core of city, but it is difficulty to processing. And in the second circle and suburb, there is no bulk transfer encouragement, which is not fit for the development policies.Under the circumstance against policy & both hurting public and private. It¡¦s difficult for the bulk transfer policy to make great achievements.From the reference documents and case data, we farther find that a bulk transfer case should catch with the development trend of the local real estate market in order to succeed.In interviewing , all the interviewees have the same point of view: In Taipei city and county, because of highly urban development, gathering population and high profit of real estate, the bulk transfer already extremely popular. Comparatively, in Kaohsiung city, because of industry depression, purchasing power drop, no population growth and real estate market is difficult to promote the bulk transfer policy. Because, whether the bulk receving lots can create the profit is the key point for bulk transfer to become popular.

Thesis (Ph. D.)--Virginia Polytechnic Institute and State University, 1985. / Vita. Abstract. Includes bibliographical references (leaves 142-148). Also available via the Internet.

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Las propiedades físicas de las resinas compuestas son muy importantes, por ello el objetivo del presente estudio fue determinar la profundidad de polimerización de las resinas “bulk fill” al ser fotoactivadas a diferentes distancias. La parte experimental se realizó utilizando el método ISO 4049, se elaboraron 36 moldes cilíndricos de 4mm de diámetro y 12 mm de altura, en las cuales se colocó la resina; se elaboraron 12 muestras de cada resina (resina A y resina B) y se dividieron de acuerdo a la distancia de fotoactivación (0mm y 4mm) por lo que se obtuvieron 6 grupos con 6 muestras de resina en cada grupo, todas se polimerizaron por LED a 10 segundos. La medición de la altura absoluta polimerizada de las muestras se realizó con un micrómetro de 0,01mm de precisión, finalmente cada altura absoluta fue dividida entre 2 lo cual se registró como la profundidad de polimerización de cada muestra. Los datos fueron sometidos a la prueba T-Student para muestras independientes y a la prueba ANOVA con un nivel de confianza de 95%. Los resultados mostraron que la resina A presentó mayor profundidad de polimerización que la resina B para las dos distancias de fotoactivación (0mm y 4mm). Los datos mostraron valores de p<0.05 siendo estadísticamente significativa entre las resinas evaluadas. Se concluyó que las profundidades de polimerización de las resinas “bulk fill” están determinadas por la distancia de fotoactivación, la resina A presenta mayor profundidad de polimerización que la resina B. Palabras claves: profundidad de polimerización, resinas compuestas bulk fill. / --- The physical properties of the composites are very important so the aim of this study was to determine the depth of cure of resins "bulk fill" photoactivated at different distances. The experimental part was carried out using the ISO 4049 method, cylindrical molds 36 of 4mm diameter and 12 mm in height, in which the resin is placed is produced; 12 samples of each resin (resin A and resin B) were prepared and divided according to the distance of photoactivation (0mm and 4mm) so 6 groups were obtained with 6 resin samples in each group, all were polymerized by LED 10 seconds. Measuring the absolute height of all samples it was performed using a micrometer of 0.01mm accuracy absolute height finally each was divided between 2, which was recorded as the depth of cure of each sample. The data were submitted to the Student t-test for independent samples and ANOVA test with a confidence level of 95%. The results showed that the resin A showed further polymerisation resin B for the two distances photoactivation (0mm and 4mm). The data showed P values <0.05 were statistically significant between the resins evaluated. It was concluded that the depths of polymerization of the resins "bulk fill" are determined by the distance photoactivation, the resin A has greater depth of cure the resin B. Keywords: depth of cure, composites bulk fill.