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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
91

Variation and availability of nutrients in co-products from bio-ethanol production fed to ruminants

Nuez-Ortin, Waldo Gabriel 15 April 2010 (has links)
The main objective of this project was to investigate the effects of the type of dried distillers grains with solubles (wheat DDGS, corn DDGS, and blend DDGS (eg. wheat:corn = 70:30)) and bio-ethanol plant origin on the nutrient variation and availability in ruminants. In addition, DDGS products were studied as opposed to their parental grains. The project was divided into the several following studies. In Study 1, we studied the nutritive value of DDGS products in terms of (1) chemical profiles, (2) protein and carbohydrate sub-fractions associated with different degradation rates, and (3) digestible component nutrients and energy values using the NRC 2001-chemical approach and the in situ assay-biological approach. Also, we tested the validity of acid detergent insoluble crude protein (ADICP) and acid detergent lignin (ADL) to predict the potential degradability of DDGS. Due to starch fermentation in the ethanol process, the chemical components in DDGS became approximately threefold more concentrated than in feedstock grains. Slowly degraded protein (PB3) and unavailable protein (PC) increased in DDGS, indicating a decrease in the overall protein degradability in the rumen. Intermediately degraded protein (PB2) was higher for corn DDGS than for wheat DDGS and blend DDGS (54.2 vs. 27.7 vs. 30.8 %CP), while PB3 was higher for wheat DDGS and blend DDGS (29.9 vs. 51.2 vs. 53.2 %CP). Mainly as a result of differing heat conditions, PC differed significantly between wheat DDGS originated at different bio-ethanol plants (0.7 vs. 7.6 %CP). The prediction of truly digestible CP (tdCP) and NDF (tdNDF) differed between the NRC 2001-chemical approach and the in situ assay-biological approach; however, both approaches reported similar energy values. These values were the highest for corn DDGS (DE3X: 3.9 Mcal kg-1), followed by blend DDGS (DE3X: 3.6 Mcal kg-1), and wheat DDGS (DE3X: 3.4 Mcal kg-1). Corn DDGS was superior to corn, wheat DDGS was similar to wheat and corn, and blend DDGS was similar to corn. No significant differences in energy values were reported between bio-ethanol plants. ADICP was not an accurate indicator of the potential degradability of protein in DDGS samples, while ADL seemed to be an acceptable indicator of the potential degradability of DM (r = -0.87; P<0.01), CP (r = -0.89; P<0.01), and NDF (r = -0.82; P<0.01) in wheat DDGS samples incubated in rumen during 48 h.<p> In Study 2, we studied the ruminal and intestinal digestion profiles and the hourly effective rumen degradation ratios between nitrogen (N) and energy. The results showed a reduction in the effective degradability of DM (EDDM), OM (EDOM) and CP (EDCP) of wheat DDGS relative to wheat; however, corn DDGS remained the same as corn. The effective degradability of NDF (EDNDF) did not vary between the DDGS samples and feedstock grains. Among DDGS types, EDDM ranged from 52.4 to 57.7 %, EDOM from 46.4 to 53.5 %DM, and EDCP from 34.0 to 45.6 %CP, being higher as the proportion of wheat in feedstock increased. No significant differences in EDDM, EDOM, EDCP and EDNDF for wheat DDGS were detected between the different bio-ethanol plants. The hourly effective degradability ratios between N and energy indicated a potential excess of N in rumen when DDGS samples were evaluated as single ingredient. This excess increased as the proportion of wheat in feedstock increased. Estimated intestinal digestibility of rumen bypass protein (IDP) was similar between wheat and wheat DDGS, but higher in corn DDGS than in corn. Blend DDGS had the highest IDP (93.9 %RUP). Due to the significantly different PC sub-fraction found in wheat DDGS originated at the different bio-ethanol plants, a large but numerical difference was detected in IDP (89.4 vs. 75.9 %RUP).<p> In Study 3, we used both the DVE/OEB System and the NRC 2001 Model to reveal the metabolic characteristics of DDGS protein and predict the protein supply to dairy cattle. The two models showed higher protein values (DVE or MP) for DDGS samples than for feedstock grains. The higher IDP for blend DDGS largely contributed to the higher protein value relative to wheat DDGS and corn DDGS (MP: 277 vs. 242 vs. 250 g kg-1 DM). Similarly, protein values differed significantly between the bio-ethanol plants mainly as a result of the numerical but large difference in IDP (MP: 272 vs. 223 g kg-1 DM). According to the two models, the degraded protein balance for DDGS products was higher than in the parental grains. Wheat DDGS showed the highest potential N excess (DBPNRC: 78 g kg-1 DM). For corn DDGS, however, the DVE/OEB System suggested a potential N excess (11 g kg-1 DM) while the NRC 2001 Model exhibited a potential N deficiency (-12 g kg-1 DM). The degraded protein balance for wheat DDGS was similar between the different bio-ethanol plants.<p> In conclusion, the chemical and biological characteristics of DDGS varied among types and between wheat DDGS samples manufactured at the different bio-ethanol plants. Thus, it is inappropriate to assume fixed values for the nutritive value of DDGS without considering factors such as type of grain used and bio-ethanol plant origin. Further research with higher number of samples will help to clarify the use of the chemical profile to predict energy values and the potential degradability of DDGS.
92

Changes in Obesity-related Food Behavior: A Nutrition Education Intervention to Change Attitudes and Other Factors Associated with Food-related Intentions in Adolescents: An Application of the Theory of Planned Behavior

Carson, Diane E. 2010 May 1900 (has links)
This research examines the effect of a nutrition education intervention to change attitudes and other factors associated with eating breakfast and consuming low-fat dairy and whole-grains. Adolescents (n = 106) 11 to 15 years old were recruited from afterschool programs in Los Angeles County, California. Participants in the treatment group (n = 57) met once weekly for 60 minutes during seven weeks. The curriculum focused on changing attitudes, subjective norms, and perceived behavioral control toward eating breakfast along with including low-fat dairy and whole grains. The first three lessons focused on basic nutrition concepts. The later lessons focused on identifying barriers and overcoming barriers, goal-setting, and identifying methods to stay motivated. Questionnaires were administered at baseline and post-intervention. Data were analyzed using SAS statistical analysis program (v. 9.2). Eighty-eight percent of participants were Hispanic, 55% were girls, and mean age was 12 years. One-hundred six adolescents completed the questionnaire at baseline and 75 completed it at post-intervention. Cronbach alpha statistic for subjective norms and attitudes toward eating breakfast, consuming low-fat dairy and whole-grains were 0.67 and higher for each dependant variable. Intention was significantly predicted by attitudes, subjective norms, and perceived behavioral control; however, as these models do not differentiate change, additional models were run with interactions between group (treatment versus control) and the change variables. Significant changes in perceived behavioral control were observed among participants in the treatment group regarding drinking skim milk, 1% milk, and 2% milk respectively (p < .05; p < .001; p < .001) and attitude (p < .05). No change was observed in breakfast eating or consumption of wholegrains
93

Boosting Lunch Is In The Bag

Almansour, Fawaz 20 August 2015 (has links)
Lunch Is In The Bag (LIITB) was a multi-level behavioral intervention with the goal of increasing the amounts of fruits, vegetables, and whole grains that parents pack in their preschoolers' lunches. The purpose of this dissertation project was to: 1) to examine the temperatures of perishable food items packed in preschoolers' sack lunches; 2) to examine parents' psychosocial constructs that relate to packing fruits, vegetables, and whole grains at four periods during the booster study; 3) to assess the servings of fruits, vegetables, and whole grains with the related nutrient content at four periods during the booster study. The four assessment periods are before LIITB, after LIITB, before the one-week booster, and after the one-week booster. Results showed that more than 97 percent of perishable food items in the sack lunches were stored at unacceptable temperatures (40-140°F). Servings of vegetables (-0.15, p=0.05) and whole grains (-0.53, p<0.0001) in preschool lunches decreased significantly before the booster in the intervention group. The booster increased the servings of vegetables (0.10, p=0.09) and whole grains (0.16, p =0.01) compared to booster baseline. The one-week booster increased thiamin, dietary fiber, and vitamin C content of foods in preschoolers' lunches. During the booster study, parents experienced improvement in psychosocial variables after LIITB and before the booster. Knowledge decreased before the booster. Parents' psychosocial variables were linked to packing more vegetables and significantly more whole grains due to the intervention. Education for parents and the public must focus on methods of packing safe, healthy lunches in order to prevent foodborne illness and chronic disease. The results of this study provide data for continued examination of an area of parental behavior related to packing lunches for their children. The booster study demonstrated that a booster was important for maintenance of program outcomes, and to increase the servings of vegetables and whole grains that parents packed in their preschool children's lunches. / text
94

Small Grains Variety Evaluation at Maricopa, Coolidge and Yuma, 2010

Ottman, M. J. 09 1900 (has links)
Small grain varieties are evaluated each year by University of Arizona personnel. The purpose of these tests is to characterize varieties in terms of yield and other attributes. Variety performance varies greatly from year to year and several site-years are necessary to adequately characterize the yield potential of a variety. A summary of small grain variety trials conducted by the University of Arizona can be found online at http://ag.arizona.edu/pubs/crops/az1265.pdf.
95

Wheat and Barley Varieties for Arizona 2013

Ottman, Michael J. 11 1900 (has links)
Revised
96

Commercial Production of Wheat Grain Irrigated with Municipal Wastewater

Day, A. D., McFadyen, J. A., Tucker, T. C., Cluff, C. B. Unknown Date (has links)
Authors' manuscript; no date on item. / Experiments were conducted in southern Arizona to study the effects of irrigating wheat (Triticum aestivum L.) with a mixture of pump water and wastewater and pump water alone on wheat growth, grain yield, grain quality, soil properties, and irrigation water quality. In small plot research, wheat irrigated with a mixture of pump water and wastewater produced taller plants, more heads per unit area, heavier seeds, higher grain yields, and higher straw yields than did wheat grown with only pump water. When large fields were compared, wheat grown with a mixture of pump water and wastewater had taller plants, more lodging, lower grain volume-weights, and higher grain yields than did wheat produced with pump water. The pH and exchangeable sodium of soil irrigated with pump water alone or a mixture of pump water and wastewater were similar. Electricalconductivity and nitrate-nitrogen were higher in soils irrigated with pump water than they were in soils irrigated with a mixture of pump water and wastewater. Extractable phosphorus was higher in soils irrigated with a mixture of pump water and wastewater than in soils irrigated with pump water. Total soluble salts and nitrate-nitrogen were higher in pump water than they were in the pump water and wastewater mixture; however, the pump water and wastewater mixture had a higher level of phosphorus than did pump water.
97

Potential of Wastewater for Commercial Barley Production

Day, A. D., McFadyen, J. A., Tucker, T. C., Cluff, C. B. 21 March 2014 (has links)
No date on item; authors' manuscript. / Experiments were conducted in southern Arizona to investigate the effects of irrigation with pump water and a pump water-wastewater mixture on barley (Hordium vulgare L.) growth, grain yield, and grain quality; soil properties; and irrigation water quality. In 1974 and 1975, on small plot research, barley irrigated with a 50:50 mixture of pump water and wastewater significantly exceeded barley irrigated with pump water alone in plant height, number of heads per unit area, number of seeds per head, seed weight, grain yield, and straw yield. In large field studies conducted from 1970 through 1977, barley irrigated with the mixture had taller plants, more lodging, lower grain volume-weights and higher grain yields than barley irrigated with pump water alone. Soils irrigated with both types of irrigation water had similar pH. Soluble salts (ECx103), exchangeable sodium percentage, nitrate-nitrogen, and extractable phosphorus were significantly higher in soils irrigated with the pump water-wastewater mixture than in soils irrigated with pump water. Water quality analyses showed that the pump water-wastewater mixture had lower total soluble salts, lower nitrate-nitrogen, and higher phosphorus levels than pump water alone.
98

Air rise through an immersed granular bed : - bulk and surfaces dynamics

Varas Siriany, Germàn 17 November 2011 (has links) (PDF)
When air is injected at the bottom of an immersed granular layer, it crosses the system by percolating or fracturing. It thus forms several paths that reach the free surface of the layer at different locations. In this thesis, we study this process experimentally (for a three and two dimensional setup), numerically and theoretically. First, we focus on the dynamics of the air invading the medium at short and long time scale, when injecting a continuous air flow. At long time, the typical size of the region explored by the air can be accounted for by a diffusion-like process [1]. We also investigate the effect of gravity by tilting the experimental cell. We contrast the results with numerical simulations for the injection of a fixed volume of air, and characterize the morphology of the invasion zone. We show that the typical height and width of the region explored by the air does not depend on the injected volume only, but also on a dimensionless parameter χ which accounts for the relative effects of the gravity and capillarity [2]. Finally, when increasing the water height above the granular layer, successive grain advection and deposition form a crater consisting of two dunes growing and moving apart one from the other. We observe that the typical size of the crater increases logarithmically with time, independently of the gas emission process [3].References -[1] G.Varas, V. Vidal and J.-C. Géminard, Phys. Rev. E. 83, 011302 (2011).[2] G.Varas, V. Vidal and J.-C. Géminard, Phys. Rev. E. 83, 061302 (2011).[3] G.Varas, V. Vidal and J.-C. Géminard, Phys. Rev. E. 79, 021301 (2009).
99

Net energy of wheat-corn distillers dried grains with solubles for growing pigs as determined by the comparative slaughter, indirect calorimetry, and the chemical composition methods

Ayoade, Deborah 17 January 2012 (has links)
ABSTRACT Two experiments were conducted to determine the net energy (NE) of wheat-corn distillers dried grains with solubles (wcDDGS) using the comparative slaughter (CS), the indirect calorimetry (IC) and the chemical composition (CH) methods. Based on the CS method, NE values of 2,407, and 2,424 kcal/kg DM were obtained for wcDDGS included at 15% and 30%, respectively. For the IC method, the NE values of 2,407, and 2,403 kcal/kg DM were obtained for wcDDGS included at 15% and 30%, respectively; corresponding values for the CH method were 2,536 and 2,197 kcal/kg DM, respectively. It is concluded that NE value of wcDDGS ranges from 2,367 kcal/kg DM to 2,416 kcal/kg DM depending on the method used. As the values obtained from the various methods were not different, the average NE value for the wcDDGS evaluated was 2,396 ± 25.71 kcal/kg DM.
100

Absorption and accumulation of cadmium from cereal grains

Moberg Wing, Anncatherine January 1993 (has links)
Cadmium (Cd) is a potentially toxic trace element. Cereal grains contribute one-third to one-half of the Cd exposure via the diet. Among cereal grains, wheat generally contains the highest Cd concentration and the bran and germ fractions contain more Cd than the endosperm. An increase in the consumption of unrefined grains may cause an increase in the body burden of Cd if an increase in the exposure to Cd via the diet leads directly to increased Cd absorption and accumulation. However, there is evidence that certain factors may reduce the availability of Cd for absorption from the diet. The purposes of these studies were to refine an atomic absorption spectrometric method for measuring the accumulation of Cd from diets with low, naturally occuring concentrations of Cd, to evaluate the extent to which Cd is accumulated from different milling fractions of wheat and from different cereal grains, and to determine to what extent the presence of certain minerals and mineral-binding factors in the diet and the iron (Fe) status of the individual affect Cd accumulation from cereal grain diets. The results of the method studies showed that the amount of Cd in the liver and kidneys of rats after six weeks on different diets and the retention of 109Cd in these organs three weeks after the ingestion of 109Cd-labelled test meals of the diets were in agreement on the fractional and total accumulation of Cd from the diets. To a first approximation, the accumulation of Cd in the liver and kidneys in rats appears to be the product of the separate effects of the concentration of Cd in the diet which is available for absorption and the Fe status of the rats. The Cd concentration in grains varied by a factor of five between whole wheat and rye and the amounts of Cd accumulated in rats from diets with whole grains were nearly proportional to the Cd concentrations in the grains. The fractional accumulation of Cd was lower in rats given diets with whole grains or wheat fractions high in fiber and phytic acid than in rats fed endosperm wheat diets. This lower fractional Cd accumulation did not compensate for the high Cd concentrations in whole wheat and wheat bran. The fractional accumulation of Cd in the liver of rats is inversely related to their Fe status. The fractional Cd accumulation in the liver of rats with low Fe status was as much as ten times that in rats with high Fe status. The Cd accumulation in the kidneys appears to be even more sensitive to Fe status. The accumulation of Cd in human placenta supports these conclusions. Women who eat diets with less cereal grain fiber and who also maintain their Fe stores during pregnancy generally accumulate less Cd in the placenta than those who eat more grain fiber and/or have lower Fe status. On the basis of these results, it is recommended that as much as possible of the dietary fiber from cereal grains should derive from grains with low Cd concentrations. It is also imperative that the diet provide sufficient Fe and other nutrients to promote Fe status and thereby limit Cd accumulation. / <p>Diss. (sammanfattning) Umeå : Umeå universitet, 1993, härtill 5 uppsatser.</p> / digitalisering@umu

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