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Swales are designed to infiltrate runoff from intermittent storm events. Present design methodologies have resulted in swales which operate under several conditions; these conditions are soil, vegetation, climatic and geographical location dependent. To attain a swale design which considers and accounts for the important factors under Florida conditions, adequate assessment of rainfall, overland, flow, infiltration and soil moisture must be given priority treatment. Several roadside and residential swales were studied and relationships were drawn for soil moisture, porosity and infiltration rates. A design methodology is included and computer modeling infiltration aids in the design.

This thesis contains a brief description of the apparatus, the procedure, and the results of an investigation of the absorption of cosmic rays in thin absorbers. The existence of an anomalous maximum at a thickness of 10.5 cm. of lead is reported, which is tenatively interpreted as being caused by the production of a penetrating ionizing radiation by a neutral radiation through some seemingly unknown process. / Thesis / Master of Science (MS)

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Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Earth and Planetary Sciences, 1979. / Microfiche copy available in Archives and Science. / Vita. / Bibliography: leaves 146-153. / by Kathleen Marie Parkin. / Ph.D.

Field experiments were conducted in Virginia to evaluate the efficacy of AEF-130060 03 plus AEF-107892 applied postemergence (POST) for the control of Italian ryegrass [Lolium multiflorum (Lam)] in barley [Hordeum vulgare (L.)] in comparison to other herbicides currently registered for use in wheat [Triticum aestivum (L.)] and barley. Laboratory experiments were also conducted to evaluate absorption, translocation and metabolism of AEF-130060 03 plus AEF-107892 in wheat, barley, and Italian ryegrass with or without the addition of dicamba. AEF-130060 03 plus AEF-107892 was applied alone at three POST timings. All of these applications were effective in controlling Italian ryegrass. The third application timing of AEF-130060 03 plus AEF-107892 commonly resulted in lower yields than the first or second application timing, due to increased duration of Italian ryegrass competition, increased barley injury and insufficient time for barley recovery from this injury. In the field experiment, significantly greater barley injury was observed when AEF-130060 03 plus AEF-107892 was combined with 2,4-D and dicamba. Early postemergence (EP) treatments of AEF-130060 03 plus AEF-107892 provided control of Italian ryegrass equivalent to that of delayed preemergence (DPRE) applications of flufenacet plus metribuzin when rainfall was received. However, when rainfall was not received AEF-130060 03 plus AEF-107892 provided superior control. Because the efficacy of AEF-130060 03 plus AEF-107892 is not dependant on rainfall, it should provide more consistent control of Italian ryegrass than DP treatments. Laboratory experiments indicated that Italian ryegrass absorbed greater than 2.5, 2.0, and 1.5 times the amount of applied radioactivity at 24, 48, and 96 hours after treatment (HAT), respectively, than wheat or barley. Metabolism experiments indicated that quantity of parent compound in the three species was greatest in Italian ryegrass, followed by barley and then wheat. However, the sum total of metabolites was not different between species. A higher rate of metabolism of AEF-130060 03 plus AEF-107892 was also observed in wheat and barley than in Italian ryegrass. Thus, lower absorption of herbicide by wheat and barley, coupled with a more rapid rate of metabolism, most likely accounts for differential selectivity between these plant species. No differences in absorption, translocation or metabolism were observed within the three plant species due to the addition of dicamba. An additional experiment was conducted in 2000 and 2001 to evaluate the efficacy of preemergence (PRE) and EP applications of DPX-R6447 for the control of Italian ryegrass in wheat and barley in comparison to other herbicides currently registered for use in these crops. Barley and wheat injury and yield were similar with treatments of DPX-R6447 at rates below 176 g ai/ha and treatments of flufenacet plus metribuzin applied alone in both years. Consistent Italian ryegrass control with DPX-R6447 occurred only with rates of 176 g ai/ha or greater in both years. However, these rates resulted in variable injury in both wheat and barley between years. Rates higher than 176 g ai/ha of DPX-R6447 resulted in unacceptable barley and wheat injury. The lack of consistency with regard to barley and wheat injury could limit the utility of this compound in these crops. Field trials were conducted in Virginia to evaluate herbicide programs for control of Italian ryegrass in no-till corn [Zea mays (L.)] establishment. Herbicide programs using transgenic corn hybrids were compared to standard programs that utilize non-selective herbicides in combination with high rates of triazine herbicides. Italian ryegrass control and corn yields similar to those provided by standard programs could be attained through the use of paraquat plus atrazine, and glyphosate applied in combination with atrazine or rimsulfuron plus thifensulfuron-methyl. In glyphosate-tolerant corn, EP applications of glyphosate controlled Italian ryegrass, but yield did not differ from yields of corn treated with standard PRE applications of glyphosate plus atrazine. The use of glufosinate, imazethapyr plus imazapyr, or sethoxydim with appropriate herbicide-tolerant hybrids did not demonstrate potential for improved control of Italian ryegrass. Field experiments were also conducted to investigate the incidence and severity of maize chlorotic dwarf virus (MCDV) and maize dwarf mosaic virus (MDMV) in response to POST johnsongrass control in two corn hybrids. Recent observations have indicated a lack of virus-tolerance in glyphosate-tolerant corn hybrids in Virginia. The rapidity of virus disease development in corn resulting from application of glyphosate or nicosulfuron was also investigated. The virus-susceptible glyphosate-tolerant hybrid developed significantly higher levels of virus incidence three weeks after treatment than the virus-tolerant, non-transgenic hybrid, and virus incidence and severity increased throughout the duration of the growing season. Little or no disease incidence occurred in the virus-tolerant hybrid. The virus-susceptible hybrid exhibited significant increases in disease incidence in response to any herbicide treatment applied to johnsongrass-containing plots relative to the same treatment applied to weed free plots. Johnsongrass control with nicosulfuron or glyphosate caused similar disease incidence and severity in the virus-susceptible hybrid, regardless of application method. Results of these experiments indicated that growers' choice of hybrid should focus primarily on disease resistance rather than herbicide resistance. / Ph. D.

Production of ammonia N, a-amino N, and peptide N was investigated following in vitro ruminal incubation of solvent soybean meal (SBM), dehydrated alfalfa, corn gluten feed, fish meal, distillers dried grains with solubles (DDG), cotton seed meal, brewers fried grains, meat and bone meal, blood meal, prolac, and casein (CAS). The influence of milling procedures on the production of ammonia N, a-amino N, and peptide N was also evaluated using different batches of soybean meals and distillers dried grains with solubles. The concentrations of peptide N and ammonia N measured in the cell free media at 0, 2, 4, 6, and 8 h were increased linearly (P < 0.001) with time. The mean concentrations of a-amino N were lower (P < 0.05) than the mean concentrations of peptide N and ammonia N. Production of peptide N, a-amino N, and ammonia N were varied (P < 0.05, time x protein) between proteins and between batches. Irrespective of the protein used, the amino acid composition of peptides (<3,000 MW) that appeared at 8 h had specific patterns suggesting differential utilization of peptides by ruminal microorganisms. Cell-free supernatants obtained following incubation (8 h) of SBM, CAS, and DDG were used as mucosal substrates in parabiotic chambers to quantify absorption of free and peptide-bound amino acids via ruminal and omasal epithelia of sheep. Serosal appearance of amino acids in peptide form was nearly three times higher (P < 0.001) than free amino acids. On tissue dry weight basis, serosal appearance of amino acids was greater (P < 0.01) across omasal than via ruminal tissues. There was a greater serosal appearance of amino acids from CAS than from SBM. Total, total essential (EAA), total nonessential (NEAA), and individual amino acid appearance in serosal fluids varied (P < 0.05, amino acid form x protein source) among SBM, CAS, and DDG. Collectively, these results indicate that the forestomach epithelia of sheep possess the potential to absorb ruminally derived peptides (relatively large amounts) and free amino acids (relatively small amounts). Also, the ruminal microbial degradation of dietary proteins may influence the amounts and types of free and peptide-bound amino acids absorbed via forestomach. / Ph. D.

Bulimia is often viewed as an extreme expression of eating concerns and body image disturbances that afflicts many adolescent and adult women. The cognitive strategies employed by individuals to inhibit eating and facilitate bingeing and purging are thought to include disattending internal sensations of hunger and satiety while sustaining attention on food, distorted beliefs, and interoceptive experiences (e.g., Heatherton & Baumeister, 1991). To the extent that these attentional and perceptual shifts mediate bulimic symptomatology, individuals with bulimic tendencies should exhibit certain cognitive attributes. Because hypnotizability, dissociation, and absorption have each been invoked (either directly or indirectly) as explanatory constructs for clinical and subclinical bulimia, the present study evaluated the absolute and relative effects of these factors on bulimic symptomatology in a large sample of undergraduate women (N = 309) using structural equation modeling. Following 2 assessments of hypnotic susceptibility (Harvard Group Scale of Hypnotic Susceptibility, Form A [Shor & Orne, 1962] & Group Stanford Hypnotic Susceptibility Scale, Form C [Crawford & Allen, 1982]), participants completed measures of eating disorder symptomatology (Eating Disorders Inventory-2 [Garner, 1991]; Three Factor Eating Questionnaire [Stunkard & Messick, 1985]), dissociation (Dissociative Experiences Scale [Carlson & Putnam, 1986]; Dissociation Questionnaire [Vanderlinden et al., 1993]), and absorption (Tellegen Absorption Scale [Tellegen & Atkinson, 1974]; Differential Attentional Processes Inventory [Crawford, Brown, & Moon, 1993; Grumbles & Crawford, 1981]). A final model including the latent constructs Hypnotizability, Dissociation, Absorption, and Bulimic Symptomatology provided a very good fit to the data (X 2 (58, N = 309) = 31.09, NFI = .932, CFI = .967, & RMSEA = .053). As hypothesized, dissociation was found to a have moderate effect (Standardized coefficient = .32, p < .01) on Bulimic Symptomatology when controlling for Hypnotizability and Absorption. Moreover, contrary to past research, the path between Hypnotizability and Bulimic Symptomatology and the path between Absorption and Bulimic Symptomatology were not significant. Based on these finding, we can now speak with increased confidence of a meaningful link between dissociation and the continuum of bulimic symptomatology. A pathological dissociative style appears to contribute to the development of bulimia. / Ph. D.