The purpose of this investigation was to modify the procedure of Bills, Khatri and Day for use in the development of a suitable method for determining the quantitative distribution of the free fatty acids (FFA) in normal, heated, and rancid milk and milk fractions The method consists of extracting the FFA from lyophilized milk, separating the FFA from neutral fat, converting the FFA to methyl esters, and analyzing the methyl esters by gas-liquid chromatography (GLC). The salts of FFA present in lyophilized milk or milk fractions were released by lowering the pH of the sample with H₂SO₄, and subsequently extracted with ethyl ether. The extracted FFA were simultaneously isolated from the extract and methylated by using the one-step procedure of Bills, Khatri and Day. A specially designed concentration flask was employed with a reflux system to concentrate the methyl esters. The esters were then separated by GLC. Quantitative calculations were made from the GLC peak areas using internal standards. The major esterified fatty acids of milk are n-saturated, evennumbered 4:0-18:0 and unsaturated 18:1 and 18:2 acids. The distribution of major FFA in whole milks was found to be essentially the same as that of the esterified fatty acids of milk fat. Heat treatments of milk, whether pasturization or extended holding at 100°C, effect a progressive reduction in total FFA. Decreases in long chain fatty acids are also characteristic of extended heating. Milks determined to be rancid by acid degree value and organoleptic analysis showed high levels of FFA, 1.5-3.6% of the fat content of the sample. The increases in 6:0-12:0 resulting from lipase hydrolysis approximate the amounts shown by Al-Shabibi and co-authors to produce rancid flavor when added to good quality milk. Milk triglycerides, fat globule membrane, skim milk, and buttermilk show characteristic FFA patterns which appear to be related to the solubility properties of the individual acids. Seventy-one percent of the total FFA in a given portion of 40% cream was found in the triglyceride fraction, 26% in the crudie fat globule membrane preparation and 3% in the skim milk fraction. The total concentrations of FFA were found to be: 1% of the fat in whole milk or 0.04% of the fluid milk weight; 0.16% of the total weight of 40% cream; 0.28% of centrifuged triglycerides; 1.7% of the fat globule membrane; and 0.008% of the fluid weight of skim milk. / Graduation date: 1965

The composition of dairy products can have a significant impact on a dairy manufacturer’s revenue. By including more of the low-value components (water and lactose) and less of the higher value components (fat and protein) in their products, within customer specifications, higher yields and therefore higher revenue can be attained. The purpose of this project was to optimise product composition at Westland Milk Products, and develop procedures for the maintenance of yield reporting.

No description available.

No description available.

This dissertation project examines the rhetorical performances of women who hold or have held the highest office of a nation-state. Currently, only 20 women are in such positions of political national leadership. This project asks how these women rhetorically perform--discursively, visually, and through embodied performance--their positions of power and how they are read, time again, against and with other women who have held similar positions in different geopolitical locations. Specifically, I ask how these rhetorical performances open up and/or close down the potential to confront gendered expectations of leadership. I argue that a "woman world leader" is not just a head of state, but also a symbolic heterodoxy that interrupts and reaffirms the doxa of the nation-state as an eternal structure. I analyze three rhetorical situations--autobiographies, the Council of Women World Leaders, and the nickname of "Iron Lady,"--in order to conclude that woman world leaders, as a discourse, can limit the potential for ethical rhetorical action of embodied women as world leaders. I link the function of the discourse of women world leaders to that of the "US presidency," as established by Campbell and Jamieson, in that it creates a transnational tradition of women as leaders. By researching women as world leaders, a subject of curiosity following the 2008 US Presidential campaigns, this project contributes to popular and academic discussions of power, identity, and transnational political participation at the foundation of which are writing, rhetoric, and education.

A series of studies was conducted using SEM in conjunction with chemical analysis, in situ and in vitro digestion techniques, to characterize the anatomical components from barley, corn, sorghum and wheat grains which constitute "fiber" and investigate their susceptibility to rumen microbial digestion. Fractured grains were used to identify anatomical features and cell types prior to and after extraction or digestion. Certain anatomical features, including pericarp tissue, aleurone cells, endosperm cell walls, corneous and floury endosperm tissue and lemma and palea from barley, were easily identifiable in fractured and ground grains, and in neutral detergent extracted or digested residues. In situ and in vitro incubation conditions were varied to assess the effect of concentrate and/or reduction of pH on the disappearance of identifiable grain fractions. In situ incubations were conducted using steers adapted to 0-, 30- and 90% concentrate diets. In vitro inoculum buffered at pH 7 or 6 was provided by a steer fed 0- or 90% concentrate. Tissues resistant to rumen microbial digestion during extended (144-h) in situ incubations and shorter term (12- to 48-h) in vitro incubations were primarily those identified in NDF, and included pericarp, lemma and palea, and small amounts of corneous endosperm. Remaining tissues identified included barley lemma, palea and pericarp; corn pericarp, tip cap and small amounts of corneous endosperm; sorghum pericarp and corneous endosperm with matrix and protein bodies; and wheat pericarp. In vitro disappearance of isolated NDF after 48-h ranged from 43% for barley to 89% for corn. Labile structures included embryonic tissue and portions of endosperm cell walls, protein matrix and residual starch. Resistant tissues included pericarp, aleurone cell walls, tip cap and portions of the corneous endosperm. Relative rankings of NDF digestibility under all conditions studied were similar (corn > sorghum > wheat > barley) whether determined using isolated NDF or calculated from TIVDMD residues. Neither concentrate level fed to the host animal nor pH of the in vitro incubation flask affected rankings among grains, although increasing concentrate level and/or reducing pH appeared to reduce in vitro NDF disappearance. Evaluation of electron micrographs of fractured grains suggested that similar anatomical structures in the various grains differed in their resistance to microbial digestion. For example, pericarp from barley and wheat appeared to be more resistant than that from corn or sorghum. Endosperm of barley was less resistant than that of sorghum.

Whole-body bioelectrical impedance analysis (BIA) was evaluated for its reliability and accuracy in estimating body composition in children and youth. The established electrical principle for estimating volume in a geometrical system from conductor-length('2) divided by impedance is the basis for the use of this method in humans. The hypothesis that body-height('2) divided by the resistance component of impedance (resistance index) can be used to estimate total body water (TBW), fat free body (FFB), and percent fat (%FAT) was tested. Validation studies in adults indicate BIA is a reliable and fairly accurate method of estimating TBW, FFB, and %FAT but no testing has been completed on children. The subjects were 103 nonobese and obese anglo males and females from 10 to 14 years old. Within-day reliability of resistance and reactance was assessed by analysis of variance with built-in comparisons. Between-day reliability for all measurements, made four to five weeks apart, was evaluated by test-retest correlation coefficients and paired t-tests. The criterion variables were FFB and %FAT estimated using equations developed for children and youth based on: (1) skinfolds, (2) body density, (3) TBW, (4) density and TBW, (5) density, TBW, and bone mineral content. Regression and multiple regression analyses were used to select the most accurate method of measuring FFB and %FAT and to determine the relationship among criterion variables and the following independent variables: resistance index alone and combined with sex, fatness category, sex x fatness, age, sexual maturation status, weight, anthropometric variables, and reactance. From this study the following conclusions were made: (1) BIA measurements were reliable, (2) resistance index had a linear relationship with FFB estimated from several criterion variables, (3) weight, sex, fatness category, sex x fatness, age, and sexual maturation status were significant variables for predicting criterion variables used in combination with resistance index but were not significant when anthropometric variables were included in the analysis, (4) prediction accuracy for FFB and %FAT from resistance index was fair (SEE 2.58 kg and 4.21%) and from resistance index plus anthropometric variables and reactance was good (SEE 1.88 kg and 3.26%) and similar to that from the best anthropometric variables alone (SEE 2.11 kg and 3.19%).

This study investigates the effects of writers attending to the informational needs of their readers at different times during composing. Each of 76 university freshmen enrolled in 7 sections of freshman composition and literature was randomly assigned to one of four treatment conditions: (1) no attention to audience, (2) attention to audience before and during drafting, (3) attention to audience before and during revising, and (4) attention to audience before and during both drafting and revising. Students' original and revised essays were scored holistically for overall quality and given separate holistic scores for organization, structure, development, grammar and mechanics, and attention to audience. Due to lower inter-rater reliability and other factors that are fully discussed, the study yielded no significant results.

Levels of nitrogen, phosphorus, potassium, calcium, magnesium, zinc, manganese, copper and selenium in grasses grown under rainfed conditions on different soils in the Santa Rita Experimental Range and other areas in southern Arizona were evaluated to determine whether these nutrients are deficient, sufficient or toxic to cattle. In the greenhouse, two grasses grown on five different soils representing four soil orders were fertilized with nitrogen and phosphorus and the uptake of a number of nutrients was determined. For the grasses collected from the field, the nutrient contents generally decreased with time to maturity and the highest levels were attained during August when the grasses were young, and March, the start of the spring growth. The nitrogen and phosphorus contents were lower than the requirement for grazing cattle indicating the need for supplementing protein and phosphorus. The contents of potassium, calcium, zinc, manganese, copper and selenium were adequate for grazing animals. Although the magnesium level in some cases was lower than the requirement, it was considered adequate because its deficiency is now known in warm season grasses. The nutrient contents in the grasses grown on Comoro soils were generally higher than when grown on an adjacent Sonoita soil. Soil analysis revealed no consistent pattern of the levels in these grasses and in Comoro and Sonita soils on which they were grown, except for nitrogen. The nutrient contents in the heads and leaves of two species of grasses were higher than in their stems. The greenhouse experiments showed that the vegetation on the N + P treatment was more vigorous than on the nitrogen treatment and the control, respectively. For the two grasses grown on the five different soils, the nitrogen and magnesium contents mostly were not significantly different between the three treatments, probably due to the dilution effect resulting from the vigorous vegetative growth on the N + P treatment. The phosphorus content in the grasses grown on the N + P treatment was significantly higher than the other two treatments. The nitrogen and phosphorus levels in the soils before and after planting were similar indicating that nitrogen and phosphorus fertilization helped maintain their levels in the soils. Other nutrients in the soils decreased after planting. Most of the nutrients were higher in the surface soils than in the subsurface soils, probably due to the ability of grasses to recycle nutrients from the subsoil.

The equilibrium equations relating dissolved CO2 , HC03- CO3-, H+, solid phase CaC03 , exchangeable H+ and ionic strength were programmed for simultaneous solution on a 7072 IBM digital computer. This routine was combined with an eXisting program which had been successfully used to relate the equilibrium of soluble and exchangeable Ca+ + ,Mg+ + ,Na+; dissolved Cl - , S04- ' and N03-; and solid phase CaS04 •2H20. The final systems analysis model thus developed accounted for most of the dissolved substances normally present in significant quantities in ground waters and soil solutions. This model made possible calculation of the equilibrium concentrations which would result if the concentration of one or more of these constituents were to be arbitrarily changed. This systems analysis model was used to predict the equilibrium concentrations of ionic species in soil solutions obtained from soils at moisture and carbon dioxide levels different from those prevailing in the original analysis. The soils used in this study were vastly different in chemical characteristics, texture, and genesis. Included were soils which were both acid and basic in reaction, calcareous and noncalcareous, gypsiferous and nongypsiferous, and both high and low in organic matter. In general, the chemical predictions obtained were of about the same level of accuracy as the experimental methods used to determine these chemical constituents. Soil cores from strata underlying an irrigated area were collected, and the 1: 1 soil-water extracts of these cores were analyzed for chemical constituents. The systems analysis model developed in this study was then used to estimate the concentrations of the chemical constituents which would have been in solution in the cores at the time they were sampled. The soil solutions calculated to be in most strata were similar to the underlying ground water, thus indicating a probable common origin for the water above and below the water table. It is believed that this systems analysis approach can, with minor modification, be used to predict changes in ground water quality as water percolates through strata of known chemical characteristics.