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Pregnanediol (5B Pregnane- 3⋉- 20⋉- dial) is the chief urinary metabolite of progesterone, and as such is important in that variations in its concentration reflect variations in progesterone secretion. Estimations of pregnanediol concentration are therefore of considerable interest to the obstetrician and gynaecologist. Pregnanediol was first identified in the urine of pregnant women in 1929 by Marrian. Nearly ten years later Venning developed a method by which the glucuronic acid ester of pregnanediol could be extracted from the urine and its concentration gravimetrically determined. Numerous variations of the Venning theme were published in the next few years, each being claimed by its authors to be an improvement on the original. Most of these involved the estimation of the conjugated form, and it was a while before the advantage of estimating the hydrolysed aglycone was realized. Hydrolysis, when it was practised, resolved itself into two methods - namely, hydrolysis by heating the urine with a mineral acid, and enzymic hydrolysis by incubation with beta-glucuronidase. Acid hydrolysis, while producing a less clean hydrolysate, is more rapid and convenient than enzyme hydrolysis, and is used in the Klapper method which is presently the most widely used method in clinical studies. Klapper employs a double chromategraphic column separation of pregnanediol followed by colorimetric evaluation. Variations of Klapper's method have also appeared and not a few investigators have published comparisons of the various methods. Klapper himself compared his method to certain other methods and concluded that his was definitely superior. Of the accuracy of the Klapper method there is no doubt. Subsequent methods have proved more sensitive, but in terms of practicability Klapper's is the method of choice. As was pointed out with some complacency, "practicability is most satisfactory, one technician readily performing some twenty determinations in one week." In contrast to the flood of criticisms, comparisons, variations, claims and counter-claims which accompanied the publication of the abovementioned methods, the thin layer chromatographic method perfected by Waldi attracted very little attention. It is very much more rapid than all other existing techniques, is very sensitive, specific and of acceptable accuracy. In an attempt to ensure its usefulness for clinical and medical research laboratories, the Waldi method has been marketed in 'kit' form. It is intended primarily as a diagnostic aid in establishing pregnancy, and as such it might have enjoyed considerable application had it not been for the advent of the immunological method of pregnancy diagnosis which is very much more rapid. Nevertheless, the Waldi method, used purely as a means of assessing the pregnanediol content of the urine is extremely useful, and it is the purpose of this investigation to establish this usefulness, especially with respect to routine clinical investigations. The validity of some diagnoses which are based on pregnanediol assay results, is also investigated. As it is impossible to explain the significance or usefulness of a pregnanediol assay without first explaining the functions of progesterone, some time and space must be expended in a brief description, firstly, of the role played by progesterone in the phenomenon of the menstrual cycle, and secondly, of its vital importance in pregnancy. It must be realized that progesterone is only one of the many hormones involved in these events, but, in order to limit the introduction of extraneous detail, no mention is made of the other hormonal participants except when necessary for the understanding of the whole. It may be mentioned here that much of the evidence that was used for the elucidation of the functions and origins of progesterone, was derived from studies of its metabolite, pregnanediol.

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The structure of a stable smooth wall zero pressure gradient turbulent boundary layer is investigated experimentally in order to determine the dominant outer region structure and to develop a hypothetical generalized boundary layer flow model. Three hot wire configurations, two vertically separated X-wires and a leading straight wire, a horizontal rake of 5 straight wires, and a vertical rake of 5 straight wires were used in the experiments, conducted at Reɵ = 8200. The basis for data reduction procedures came from crosscorrelations and the Variable Interval Time Average (VITA) technique. Three structure types are reported in the literature to be important: streaks and counter rotating streamwise vorticity, wall scaled hairpins or ring vortices, and large scale (0(ઠ)) bulges. A simple pictorial model consisting of three Reɵ dependent interdeveloping stages, which integrate all three structure types, is presented and discussed in relation to the literature and experiments performed. The rake data indicate that the positive ([formula omitted]u/[formula omitted]t) VITA detected velocity front has a scale much larger than that of the wall scaled eddies which typically have a scale of 100-300 y[formula omitted], and that this velocity front exhibits characteristics that are consistent with the trailing velocity front described in the model. The general convection velocity from basic crosscorrelations and the convection velocity of the positive VITA detected velocity front both had values 90-100% of the local mean velocity over most of the boundary layer. Evidence of small scale structure concentration on the downstream edge of the trailing velocity front is presented. A new method used to determine the average structure inclination angle associated with the trailing velocity front is presented and demonstrates that the generalized structure inclination angle, calculated from basic crosscorrelations between vertically separated sensors, does not indicate structure shape, but is associated with the bulk flow associated with the structure. The new method appears to give results that are consistent with flow visualization and more accurately estimates the inclination angle associated with the most dominant feature of the outer flow, the positive VITA velocity front. Although the model presented is somewhat crude and further development and refinement are required, the model appears to agree with most data in the literature, as well as the present experimental results. / Applied Science, Faculty of / Mechanical Engineering, Department of / Graduate

Analytical and numerical analyses along with experimental results are presented for laminar forced convection from a heated flat plate. The heating is of either the constant flux or constant temperature type with a discontinuity in the lateral as well as the free-stream direction. The principal objective was to examine the disturbance created by the lateral discontinuity in heating. Analytical solutions of the boundary layer type relating the wall temperature variation to a specific heat flux distribution were found. These involve Heaviside calculus, Fourier transform techniques and the Lévque velocity approximation, and although formally correct only as the Prandtl number approaches infinity, are found to be fairly accurate for Prandtl numbers as low as unity. Reduction of the energy equation to a two-dimensional elliptic equation by a double similarity transform enabled the calculation of numerical solutions valid in any free-stream cross-section removed from the leading edge. Results for technologically interesting cases of heated strips were found by superposition. The error in assuming such strips to be two-dimensional throughout their lateral extent is calculated. A velocity profile corresponding with the Blasius profile and a cross-sectional temperature field above a wind tunnel model of a heated flat plate were measured with a constant temperature anemometer and a rake of miniature thermocouples respectively. A temperature profile well into the heated portion is of two-dimensional form and the temperature field at the lateral step correlates with a numerical solution. In general, there is good agreement between all three approaches. / Applied Science, Faculty of / Mechanical Engineering, Department of / Graduate

Some conductive and convective heat transfer problems with radiative boundary conditions are analysed theoretically. Three specific problems have been analysed. The study has, therefore, been divided into three parts. In Part I the temperature distribution produced in-long, solid circular and rectangular cylinders and a solid sphere in interplanetary space is studied. The solid bodies receive parallel radiation flux on one side and emanate radiant energy to their surroundings at zero degree Rankine. Steady state, constant physical and surface properties, and no heat loss by convection are assumed. Solution of the linear conduction equation with nonlinear boundary conditions is obtained by two approximate, semi-analytical methods, (i) point matching and (ii) least-squares fitting. The results are compared with earlier results obtained by a variational method. The least-squares fit method appears to be most suitable regarding accuracy and simplicity in computation. Its accuracy does not appear to depend appreciably either on the radiation-conduction parameter or on the surface absorptivity. The effect of semi-grayness of the receiving surface is analysed. In Part II the heat transfer characteristics of a circular fin dissipating heat from its surface by convection and radiation are analysed. The temperature is assumed uniform along the base of the fin and constant physical and surface properties are assumed. There is radiant interaction between the fin and its base. Two separate situations are considered. In the first situation heat transfer from the end of the fin is neglected. Solution of the linear conduction equation with nonlinear boundary conditions has been obtained by the least-squares fit method. A solution has also been obtained by the finite difference method and the results compared. Results are presented for a wide range of environmental conditions and physical and surface properties of the fin. In the second situation heat transfer from the end of the fin is also included in the analysis. The solution is obtained by a finite difference procedure. It is shown that neglecting heat transfer from the end is a good approximation for long fins or for fins of high thermal conductivity material. In Part III the problem of laminar heat transfer in a circular tube under radiant heat flux boundary conditions has been analysed. Fully developed velocity profile is assumed and the tube is considered stationary. A steady radiant energy flux is being incident on one half of the tube circumference while the fluid emanates heat through the wall on all sides by radiation to a zero degree temperature environment. A solution by finite difference procedure has been obtained. The temperature distribution and the Nusselt number variation are presented for a wide range of the governing physical parameters. / Applied Science, Faculty of / Mechanical Engineering, Department of / Graduate

M.Ing. / The goal of the project was to stimulate aspects of the atmospheric boundary layer. As a result of the complexity of the derived models, it was decided to rather do an experiment on turbulent Couette flow to simulate. some aspects of the atmospheric boundary layer. A Couette flow channel with a maximum wall speed of 1 m/s was built. Experiments were done at two Reynolds numbers, l600 and 2500, corresponding to a channel height of 0.06 m and belt speeds of 0.4 mI and 0.58 m/s, respectively. The Coutte channel has the facility that the supper stationary wall can be heated or cooled. Experiments were carried out with positive and negative temperature gradients for both the Reynolds numbers giving the following results. By heating the top wall a stratified flow results which leads to no mixing of the flow properties. This phenomena is analogous to night time conditions in the atmosphere, when layers at different temperatures form a layered structure with little mixing between layers.

CHARLES UNIVERSITY FACULTY OF PHARMACY IN HRADEC KRÁLOVÉ Department of Pharmaceutical Chemistry and Pharmaceutical Analysis Candidate: Aneta Ptáčková Supervisor: PharmDr. Lukáš Lochman, Ph.D. Title of thesis: Modification of capillary wall by graphene for separation applications Capillary electrophoresis (CE) is a highly efficient separation method. Substances are separated due to their different mobility in an electric field. The CE modes of operation can be modified in different ways, e.g. capillary electrochromatography or micellar electrokinetic capillary chromatography. Modification of the inner wall of the capillary is believed to help improve separation efficiency and selectivity. Graphene is carbon with a hexagonal structure in form of two-dimensional sp2 single-atom-thick sheets. Graphene seems to be a suitable material for separation application due to its excellent properties such as large surface area and affinity to aromatic ring through π-π interactions. Our work is focused on the modification of the capillary wall by graphene. One of the methods of capillary wall modification is the Layer-by-Layer method via layering of differently charged substances bounded by electrostatic forces. Another method is chemical coating employing covalent interactions. Different combinations of polymers...

In times of economic hardship, everyone must find ways to adapt, and the poultry industry is no exception. The majority of the cost in an integrated poultry operation is feeding the birds. Distillers dried grains with solubles (DDGS) has been around for decades as a by-product of the beverage industry and more recently as a co-product of the ethanol industry. Over the past decade, there has been a dramatic increase in the production of DDGS from U.S. ethanol biorefineries, making the co-product a very economical choice. DDGS have not held a common place in the poultry industry for long though, as issues with nutritional variability, storage, transportation, etc. all have led to the product being avoided by nutritionists much of the time. Even now, DDGS are fed at a relatively low inclusion level compared to other major feed ingredients such as corn, wheat and soybean meal. With the often volatile price of corn grain, DDGS are receiving more attention as a feasible alternative in commercial poultry diets as research, such as that presented in this dissertation, continues to elucidate the nutritional, economical and dietary inclusion aspects of this once neglected ingredient. The primary purpose of this research has been to determine the efficacy of DDGS as an ingredient in poultry diets, and also to further elaborate on the suitable inclusion rates in a ration. In the end it is clear that DDGS are an effective and suitable choice for inclusion into both broiler and layer diets. DDGS can be incorporated into layer diets at up to one-third of the ration with no deleterious effects on performance or egg quality. DDGS can be added to broiler diets at varying inclusion levels, depending on bird age, as the research points towards increased tolerance of the co-product as the bird ages, without harming bird health or performance. It is also shown that further processing of DDGS, primarily fiber separation, can have a positive effect on bird performance. In conclusion, DDGS inclusion in poultry rations is a sound choice provided attention is paid to the nutritional profile of this co-product.

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