A rapid, chemical method for the detection and quantitation of Iipoic acid has been developed. Lipoic acid produces a yellow color when reacted with PdCl₄⁻² in 1 N HCI. The colored complex formed is extractable into methylene chloride, which can be readily concentrated, increasing the color intensity. The limit of sensitivity of this assay for lipoic acid detection in supernatants from Escherichia coli K-12 cell cultures is 2.5 x 10⁻⁵ M, giving an absorbance of 0.10 at 408 nm. Using this assay, it would be possible to screen for a mutant of Escherichia coil K-12 which excretes 100-fold more lipoic acid than the parent strain. Cellular lipoic acid in an anaerobic Escherichia coli K-12 culture remained constant (5 to 6 µg/g dry weight) during growth in a. minimal salts medium containing 1% glucose. However, cellular lipoic acid in an aerobic Escherichia coli K-12 culture increased from 15 µg/g dry weight to 20 to 25 µg/g dry weight during cell growth in the same medium. Aeration (2 L air/L medium/ minute) of a mid-log phase anaerobic Escherichia coli K-12 culture resulted in a doubling of cellular lipoic acid levels within the first thirty minutes and a four fold increase over the next five hours of aerated cell growth. Chinese hamster ovary cells were found not to incorporate the two known bacterial precursors, [²H₃]-acetate and [U-²H₁₅]-octanoate, into lipoic acid. Further studies with both Chinese hamster ovary and mouse fibroblast cells which were designed to demonstrate that these two transformed eel 1 1 ines require lipoic acid for maximal growth were inconclusive. / Master of Science

Kinetic data on soot and pyrolytic graphite oxidation rates have been used to calculate the ability of woodstove catalysts to burn woodstove effluent particles. Large variations appear in the literature and depending upon which particle diameter and rates were used one can calculate maximum possible particle oxidation efficiencies of 10⁻¹ to 40 per cent, with most investigators predicting less than a 1 per cent efficiency. This suggests that the 80 per cent reduction in "particulate" emissions which is shown by tests with catalyst-equipped stoves is due to catalytic oxidation of high molecular weight vapors rather than due to particle burnup. Dilute (500 and 250 ppm) acetylene/air mixtures flowing between parallel catalytic plates have been studied experimentally. Measured acetylene profiles for the hydrodynamic entry length region are presented and compared to profiles calculated by a single-phase, two-dimensional, low mass transfer analytical model currently under development and which eventually will be extended to cover three-dimensional flows such as those in the passageways of a woodstove catalyst. The measured temperature profile for a 5000 ppm acetylene/air mixture flowing between parallel catalytic plates was compared to the temperature profile calculated by a single step, adiabatic, constant pressure, homogeneous model. / Master of Science

The preferential adsorption of n-decanol, n-decylamine, n-decanoic acid, and ethyl octanoate from binary solutions with heptane onto alumina was studied. The net surface excess isotherms were measured and resolved into component isotherms. The heat of immersion of the alumina in n-decanol, ethyl octanoate, and n-decanoic acid solutions was measured. The heats of immersion support the resolved isotherms which indicate that the order of preferential adsorption is n-decanoic acid > n-decanol ≃ n-decylamine ≃ ethyl octanoate. However, adsorption equilibrium constants calculated for each system indicate that the order of preferential adsorption is ethyl octanoate > n-decanol > n-decylamine > n-decanoic acid. An explanation for the discrepancy is put forth. A theoretical model of surface heterogeneity is also applied to the data for the ethyl octanoate and n-decanol systems. The reasonable fit of the model in each case suggests that the alumina surface is heterogeneous. / Master of Science

Calcium is an important factor in many cellular activities and in the maintenance of structural integrity of membranes. Calcium accumulation in the rat lens above the normal physiological range (0.11 µmol/g wet weight) has been associated with formation of cataracts. Selenite is known to influence the histological characteristics of the lens and also alter important biochemical functions. In the selenite induced cataract calcium levels increase as much as 5-fold above normal, the increase preceding appearance of mature opacity by 24 hours. Calcium in the lens rapidly exchanges with labelled calcium in the incubation medium and. establishes equilibrium within 30 minutes. Selenite, accumulated in lens in vivo, causes a 5-6 fold increase in lens calcium over controls during a 24 hour incubation in modified Hank's medium at 37°C. In vitro lmM selenite in the culture medium results in a 15-fold increase in lens calcium, a 17-fold increase in sodium/potassium ratio, and a 60% increase in lens hydration. Efflux of calcium from in vivo and in vitro selenite-treated lens is not impaired. The lens retains the capability to transport 3-4 fold greater calcium over controls from lenses which have accumulated excess calcium in the presence of selenite. In vivo selenite treatment results in a 2.5-fold increase only of extracellular water. In in vitro selenite-treated lenses, however, there is a 2.6-fold increase in extracellular water and a 1.8-fold increase of intracellular water. Selenite treatment of the lenses in vivo and in vitro causes a greater influx of calcium into the lens. Calcium accumulation may act in a nonspecific manner altering lens biochemical functions, membranes and structure, causing development of relationships between selenite induced lens fiber opacities. cataract and cell the associated changes in lens calcium content further validates this model for studying the biochemical changes which impact cataract formation. / Master of Science

Bovine morulae (day 6; n=328) were obtained to evaluate the effect of uterine flushings (UF) obtained from ovariectomized progesterone (P) or estrogen (E) treated cows or from previously superovulated cows on day 6, 10, or 15 post insemination on early embryo development. Ninety-eight cows were superovulated with follicle stimulating hormone. Embryos were collected by non-surgical flushing procedures and morphologically evaluated and randomly assigned to culture. Embryos were cultured in Ham's F-10 containing 10% steer serum (SS), 10% P or E concentrated UF, 10% SS plus 1% UF from day 6, 10, or 15, or different concentrations of UF from day 6, 10, or 15 (10%, 1%, .1%, .01%). Embryos were cultured up to the hatched blastocyst stage or degeneration and evaluated at 12 h intervals. Treatment differences were evaluated by analysis of variance after assigning a value of 0 to 5 to each embryo representing its final stage of development. Overall analysis revealed that embryo development was significantly affected by supplement, but not affected by initial quality. Final developmental score was significantly higher in SS than in all other supplements. Combination of 1% UF and 10% SS resulted in enhanced embryo development compared to all single UF protein treatments. Time to the hatching blastocyst and hatched blastocyst developmental stages was reduced (P<.05) in 1% day 15 UF compared to 1% day 6 and day 10 UF plus 10% SS, or 10% SS. These results suggest that day 15 UF may contain a substance which may shorten the time of embryo hatching in vitro. / Master of Science

A novel concept of recovering heat from hot gases using countercurrently flowing vibrofluldized solids (that is, solids levitated solely by mechanical vibration) has been proposed and tested. Based on a theoretical heat transfer model, the heat transfer coefficient between the air and the solids was calculated. A factorial design of experiments showed that a higher heat transfer coefficient was obtained with higher air flow rates and lower solid flow rates. The baffle height had an insignificant affect on the heat transfer. Tests with multiple baffles led to a maximum heat transfer coefficient (143 W/m²-K) when using four baffles. For all tests performed in this work, the solids were not truly vibrofluldized. Instead, they were merely vibro-conveyed (or vibro-shuffled) as a single mass. A new vibrating system will provide the sufficient energy for vibrofluidization, and enhanced heat transfer is expected. This work demonstrated for the first time the solid impeding phenomenon in a fluidized-bed heat exchanger. Specifically, experimental tests showed that if a baffle was lowered past a limiting height at given air and solid flow rates, the increased air velocity past a baffle could prevent the solids from exiting the exchanger. An economic evaluation showed that the vibrofluidized-bed heat-exchanger system would be economically feasible for the production of boiler feedwater using heat recovered from boiler combustion gases. The payback time for the system could be as little as 1.4 years. The convective heat-transfer data from a supernatant gas to a flowing vibrofluidized bed of solids were the first of their kind, and they have led to a better understanding of the new vibrofluidized-bed heat-exchanger system. The successful completion of this project sheds encouraging light onto future heat-recovery operations with such a system. / Master of Science

The inland interstate borderfisheries and the arrangements to manage them were identified and described by two surveys. A cartographic survey of the U.S. inland borders (excluding the Great Lakes) identified 62 rivers, 71 impoundments of non-border rivers, and 64 natural lakes, totalling 4.1 million acres. A telephone/mail survey of 48 state inland fisheries chiefs identified 68 interstate arrangements. A typology of interstate arrangements was developed and used to differentiate these along two dimensions -- type of agreement and type of management framework. Fifty-five of the 81 watered borders were covered by a Type IA arrangement that is negotiated directly between two states and does not establish an autonomous institution. Their four major functions were to (1) control fishing, ( 2) control management, ( 3) delimit the scope of the arrangement, and (4) protect the arrangement. Seventeen provisions identified matters to be addressed within each of those four functions, with specifications defining how each matter would be handled. For instance, 59 arrangements controlled the use of the resource; 56 of the 59 included a provision for type of license reciprocity; and 50 of the 56 specified simple recognition of both states' licenses. The Type IA arrangements occurred most often and were most complex on rivers -- the largest borderwater type -- and on borders that were really important to the border states. Some arrangement characteristics were highly regionalized, suggesting that the lack of communication has limited the use of promising arrangement alternatives. / Master of Science

Hemolymph of Tipula trivittata larvae permits freeze tolerance of this insect due to its content of cryoprotectants and ice nucleating proteins. Spontaneous ice nucleation of the dialyzed hemolymph occurs between -5 C and -11 C up to dilutions of 1:1000. The objectives of this study were to evaluate the effects of seeding temperature (-5 C vs -7 C), and the presence of hemolymph at a low (.1% v/v) and a high (10% v/v) level on the survival of frozen-thawed bovine embryos. In Exp. l, survival rates of 6 and 7 day bovine embryos frozen in medium containing .1% hemolymph and seeded at -5 C or -7 C, were compared to evaluate the effect of seeding temperature. The effect of hemolymph was evaluated by including a control without hemolymph seeded at -7 C. In Exp. 2, survival rates of embryos frozen with and without 10% hemolymph were compared. In Exp. 3 the evaluation of the effect of 10% hemolymph was continued. Also included was a control handled identically to embryos frozen in medium with 10% hemolymph regarding pre and post freeze manipulations but which was not frozen. This allowed evaluation of freezing damage per se. For Exps. l, 2, and 3, survival based on mean final development score and time to advance a developmental stage in vitro did not differ for embryos frozen. However, in Exp.· 3, the control which was not frozen had 30% greater survival than embryos undergoing the same manipulations but which were frozen. Thus, neither seeding temperature nor inclusion of .1% or 10% hemolymph in freezing medium had a significant effect on survival of frozen-thawed bovine embryos. / Master of Science

Alfalfa is difficult to ensile because of its low water soluble carbohydrate content, low dry matter content, and high buffering capacity. Therefore, the isolation of mutants of L. plantarum was undertaken to develop a strain(s) which could improve the fermentation of alfalfa silage when used as an inoculum. Efforts to isolate starch- or hemicellulose-utilizing strains proved unsuccessful as did the isolation of high temperature resistant mutants and oxygen resistant mutants. Mutants resistant to plumbagin (an intracellular O₂- generator) and citrate were isolated. Of these mutants, some were found to be more sensitive to cadmium than the parent strain. Though these three characteristics point to an enhanced manganese accumulation since O₂- is scavenged by manganese, citrate will chelate manganese, making it unavailable to the organism, and cadmium is transported by the manganese transport system, the rates of 54_Mn transport were no greater than the parent. When grown aerobically on a glucose-limited medium, the parent strain consumed oxygen and produced high concentrations of acetic acid and low concentrations of lactic acid. By contrast, one mutant (strain MC226), produced high concentrations of lactic acid and demonstrated low rates of O₂ consumption and low levels of acetic acid. The parent strain and two plumbagin- and citrate-resistant mutants were used to inoculate alfalfa for silage production. The inoculated silages showed a lower pH and higher titratable acidity than that of an uninoculated control. Silages inoculated with the parent strain exhibited high levels of acetic acid and low levels of lactic acid, indicative of oxygen consumption by the parent strain. Less acetic acid was evident in silages inoculated with the mutant strains. All silages contained a high level of butyric and isobutyric acids and propionic and isovaleric acids were also detected, indicative of clostridial growth. / Master of Science

Adrenal corticosterone and aldosterone content, body weight changes and serum osmolality were examined during water restriction and water deprivation. Progressive water deprivation resulted in increased serum osmolality and decreased body weight; adrenal aldosterone content did not change. Adrenal corticosterone content tended to be elevated during early water deprivation indicating a stress response, but tended to decrease after seven days of water deprivation suggesting adrenal fatigue. During water restriction, after the period of weight loss, adrenal elevated corticosterone content and serum osmolality were elevated. As the birds began to gain weight aldosterone did not change, but adrenal corticosterone content and serum osmolality approached control values, suggesting the birds were beginning to adapt to the water restriction. The lack of an aldosterone response suggests that high sodium in the diet was more important than the water regimes in regulating aldosterone. The adrenal was sensitive to ACTH as indicated by the elevated adrenal aldosterone and corticosterone content after ACTH injection, however sodium status probably affects the aldosterone response to ACTH. / Master of Science