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Effect of Yellow Pea Protein and Fibre on Short-term Food Intake, Subjective Appetite and Glycemic Response in Healthy Young MenSmith, Christopher 26 March 2012 (has links)
In order to elucidate the component(s) of yellow peas responsible for their health benefits, the effects of 10 or 20 g of isolated yellow pea protein (P10 and P20) or fibre (F10 and F20) on food intake (FI) at an ad libitum pizza meal served at 30 min (experiment 1) or 120 min (experiment 2), blood glucose (BG) and appetite in young healthy males (20-30 y) were investigated. In experiment 1, P20 suppressed FI compared to all other treatments and lowered cumulative FI (pizza meal kcal + treatment kcal) compared to F10. Protein treatments suppressed pre-meal (0-30 min) BG compared to control, whereas only P20 suppressed post-meal (50-120 min) BG. In experiment 2, there was no effect of treatment on any outcome measures. Thus, protein is the component responsible for the short-term effects of yellow peas on glycaemia and FI, but its second-meal effects diminish by 2 hours post-consumption.
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High Folate, but not High Multivitamin Gestational Diets, Affect the Serotonergic Regulation of Food Intake in Female Wistar OffspringPoon, Abraham 26 November 2012 (has links)
The hypothesis that high multivitamin gestational (HV) diets affect the development of central serotonergic regulatory systems in female offspring, and that this is due to its high folic acid content, was investigated. Dams were fed the AIN-93G diet containing the recommended multivitamin mix (RV), 10-fold the RV amount (HV), or the RV diet with 10-fold the folic acid (Hfol). Serotonergic control of food intake and macronutrient selection was assessed by measuring long-term intake and selection, short-term intake and selection following injections of serotonin receptor agonists, and hypothalamic serotonin receptor expression. Offspring from Hfol dams selected more protein and were less responsive to agonist injections, but showed no altered serotonin receptor expression. In contrast, those born to HV fed dams were not different from the RV controls in any measure. In conclusion, the Hfol, but not HV gestational diet affects serotonergic regulation of food intake in female rat offspring.
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Nutritionally Adequate Protein Sources in Diets During Gestation, Lactation and Weaning Influence Food Intake and the Risk of Characteristics of Metabolic Syndrome in Offspring of Wistar RatsJahan-mihan, Alireza 31 August 2011 (has links)
The hypothesis that source of protein in a nutritionally adequate diet during gestation, lactation and weaning alters food intake and characteristics of metabolic syndrome in the offspring was investigated. Pregnant Wistar rats were randomized to either the AIN 93-G casein (C) or soy protein (S) diets (n=12/group) during gestation only or during gestation and lactation. Male offspring in each dams’ diet group were weaned to either C or S diets (n=12/group). Food intake, body weight (BW), fat pad mass, systolic (SBP) and diastolic (DBP) blood pressure, and plasma homocysteine (p<0.05) were higher in offspring born to dams fed the S diet. Fasting blood glucose (BG), BG in response to a glucose gavage and Homeostatic Model of Assessment of Insulin Resistance (HOMA-IR) index were higher only in male offspring born to dams fed the S diet. Moreover, gene expression of Agouti Related Protein (AgRP) was higher in offspring born to dams fed the S diet at weaning. Extending the dams’ diet during gestation and lactation magnified the effect of the gestational S diet on BW and composition and glucose metabolism in male offspring. Although composition of the weaning diets interacted with that of the dams’ diets, the latter was the dominant factor in determining metabolic outcomes in the offspring. In conclusion, the soy protein diet, compared to the casein diet when consumed during gestation or throughout gestation and lactation increased food intake and the presence of characteristics of metabolic syndrome in the offspring.
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Nutritionally Adequate Protein Sources in Diets During Gestation, Lactation and Weaning Influence Food Intake and the Risk of Characteristics of Metabolic Syndrome in Offspring of Wistar RatsJahan-mihan, Alireza 31 August 2011 (has links)
The hypothesis that source of protein in a nutritionally adequate diet during gestation, lactation and weaning alters food intake and characteristics of metabolic syndrome in the offspring was investigated. Pregnant Wistar rats were randomized to either the AIN 93-G casein (C) or soy protein (S) diets (n=12/group) during gestation only or during gestation and lactation. Male offspring in each dams’ diet group were weaned to either C or S diets (n=12/group). Food intake, body weight (BW), fat pad mass, systolic (SBP) and diastolic (DBP) blood pressure, and plasma homocysteine (p<0.05) were higher in offspring born to dams fed the S diet. Fasting blood glucose (BG), BG in response to a glucose gavage and Homeostatic Model of Assessment of Insulin Resistance (HOMA-IR) index were higher only in male offspring born to dams fed the S diet. Moreover, gene expression of Agouti Related Protein (AgRP) was higher in offspring born to dams fed the S diet at weaning. Extending the dams’ diet during gestation and lactation magnified the effect of the gestational S diet on BW and composition and glucose metabolism in male offspring. Although composition of the weaning diets interacted with that of the dams’ diets, the latter was the dominant factor in determining metabolic outcomes in the offspring. In conclusion, the soy protein diet, compared to the casein diet when consumed during gestation or throughout gestation and lactation increased food intake and the presence of characteristics of metabolic syndrome in the offspring.
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Computation and Analysis of EGR Mixing in Internal Combustion Engine ManifoldsSakowitz, Alexander January 2013 (has links)
This thesis deals with turbulent mixing processes occurring in internal combustion engines, when applying exhaust gas recirculation (EGR). EGR is a very efficient way to reduce emissions of nitrogen oxides (NOx) in internal combustion engines. Exhaust gases are recirculated and mixed with the fresh intake air, reducing the oxygen con- centration of the combustion gas and thus the peak combustion temperatures. This temperature decrease results in a reduction of NOx emissions. When applying EGR, one is often faced with non-uniform distribution of exhaust among and inside the cylinders, deteriorating the emission performance. The mixing of exhaust gases and air is governed by the flow in the engine intake manifold, which is characterized by unsteadiness due to turbulence and engine pulsations. Moreover, the density cannot be assumed to be constant due to the presence of large temperature variations.Different flow cases having these characteristics are computed by compressible Large Eddy Simulations (LES). First, the stationary flows in two T-junction type geometries are investigated. The method is validated by comparison with experimental data and the accuracy of the simulations is confirmed by grid sensitivity studies. The flow structures and the unsteady flow modes are described for a range of mass flow ratios between the main and the branch inlet. A comparison to RANS computations showed qualitatively different flow fields.Thereafter, pulsating inflow conditions are prescribed on the branch inlet in or- der to mimic the large pulsations occurring in the EGR loop. The flow modes are investigated using Dynamical Mode Decomposition (DMD).After having established the simulation tool, the flow in a six-cylinder engine is simulated. The flow is studied by Proper Orthogonal Decomposition (POD) and DMD. The mixing quality is studied in terms of cylinder-to-cylinder non-uniformity and temporal and spatial variances. It was found that cycle-averaging of the concentration may give misleading results. A sensitivity study with respect to changes in the boundary conditions showed that the EGR pulsations, have large influence on the results. This could also be shown by POD of the concentration field showing the significance of the pulses for the maldistribution of exhaust gases.Finally, the flow in an intake manifold of a four-cylinder engine is investigated in terms of EGR distribution. For this geometry, pipe bends upstream of the EGR inlet were found to be responsible for the maldistribution. / <p>QC 20130207</p>
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The Relationship Between Carbohydrate Restrictive Diets And Body Fat Percentage in the Female AthleteLorenzo, Lauren L 22 July 2011 (has links)
Purpose: To assess the dietary intake and body composition of recreational and competitive female athletes, for the purpose of analyzing the relationships between macronutrient intake and body composition.. The main aim was to determine the relationship between caloric intake, carbohydrate (CHO) intake and protein intake with body fat percentage in active females. Methods: Using an IRB approved protocol, 44 volunteer female recreational and competitive athletes 18 years of age or older were recruited. Interviews were conducted to gather information on within day energy balance by assessing the time and amount of foods/beverages consumed, and the duration and intensity (using a Rating of Perceived Exertion scale) of activity performed on the day of assessment. All analyses were performed using Nutritiming™ (Calorie and Pulse Technologies, Atlanta, GA) to assess energy surpluses, energy deficits, and end of day energy balance. Information on date of birth, race/ethnicity, menstrual status, sleep and wake times, and prior diagnoses of metabolic disease and/or eating disorders were collected at the time of the interview. Height was assessed using a standard stadiometer. Weight and body composition were assessed via Bioelectrical Impedance Analysis (BIA) using InBody 230 (BioSpace Co. USA). The BIA assessment was performed to determine body fat percentage, Basal Metabolic Rate (BMR), Body Mass Index (BMI), segmental body composition, and fat and lean mass in kilograms. Nutrient data were derived using an interviewer-led, 24-hour recall. Results: CHO intake/kg total mass was significantly and inversely correlated with body fat percentage and BMI, (p=0.018 and p=0.001 respectively). Protein intake/kg total mass was also inversely and significantly correlated with body fat percentage (p=0.006). Fat intake was not significantly associated with BMI, body fat percent, or lean mass in kilograms. Total energy intake/kg total mass was inversely associated with BMI (p=0.001), with fat mass (p=0.001), and with body fat percentage, (p=0.001). CHO intake/kg total mass was positively associated with the total number of hours spent in an anabolic (i.e., EB>0) state (p=0.001), and was inversely associated with the total number of hours spent in a catabolic (i.e., EB < 0) state (p=0.001). CHO intake/kg total mass was the only substrate to be significantly correlated with the number of hours spent ± 400 kcal EB over a 24 hour period (p=0.001). Z-scores were created to establish categories of body composition and energy balance values. Utilizing Chi-Square tests, it was determined that more hours spent in an energy surplus (> 400kcal) was associated with higher body fat percent (p=0.042). Conclusions: CHO restriction, whether done intentionally or as a function of an energy restrictive intake, was commonly observed in this subject pool. Of the females surveyed, 79% did not meet their daily energy needs and, on average, consumed 49% of the recommended daily intake of CHO established for active people. The findings that subjects with lower CHO intakes had higher body fat levels, and that CHO was associated with improved maintenance of energy balance, which was also associated with lower body fat percent, suggest that physically active women should not restrict CHO to achieve a desired body composition. It was also observed that end-of-day energy balance was not associated with either energy substrate consumption or body composition.
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The Effect of Adolescent Physical and Sexual Dating Violence on the Nutritional and Psychological Health of Adolescent GirlsRaiford, Jerris Laverne 12 January 2006 (has links)
The purpose of this study was to explore the stress-eating relation established in the literature by examining a naturally occurring stressor, adolescent dating violence, and its effect on eating in adolescent girls. Specifically, analyses focused on assessing the mediating role of depression in the adolescent dating violence-fruit and vegetable intake relation and the moderating role of sports team involvement in the adolescent dating violence-depression relation. A nationally representative sample of 5,892 black, Hispanic, and white adolescent girls were surveyed using measures assessing physical and sexual dating violence experiences, depressed affect, suicidal thoughts, plans, and/or attempts, fruit and vegetable intake and involvement in team sports. This study supported the hypothesis that depression mediates the relation between adolescent dating violence and dietary intake, but only in black adolescent girls. These findings suggest that black girls victimized by dating violence experience depression, which may affect their desire or motivation to eat properly. This study also supported the hypothesis that sports team involvement, a source of social support and physical activity, moderated the relation between adolescent dating violence and depression and suicidality, but only for white adolescent girls. For this group, participating on a sports team served to protect those girls reporting dating violence from experiencing depression at the high rate reported by those dating violence victims not involved on a sports team. The findings presented in this study provide evidence that depression explains how experiences of dating violence affect eating behavior for a high-risk group, black adolescent girls. Recognizing depression’s contribution to this group’s high rate of obesity and overweight is an important step in preventing obesity and obesity-related outcomes in this population. Also, this study highlights an important source of social support, sports team involvement, and its potential to protect dating violence victims from experiencing depression and suicidal ideation, plans, and attempts.
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MC3R and MC4R Knockdown via RNA InterferenceMankin, Danielle N 12 July 2012 (has links)
Melanocortins (MCs) play an important role in feeding, metabolism, and energy expenditure. While melanocortin receptor (MCR) mRNA has been found in the mesolimbic dopamine (DA) pathway, the ability of melanocortins to regulate feeding and other behaviors through actions on the mesolimbic DA system have not been examined. Short-hairpin RNAs (shRNAs) were created targeting MC3R and MC4R and were tested via in vitro studies for their ability to knockdown their target receptor. A total of three shRNAs were created targeting each receptor, and each shRNA caused successful knockdown. These shRNAs are tools that can be used for future in vivo studies to examine the various behavioral effects of melanocortins on the mesolimbic DA pathway.
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Arsenic Exposure Risk from Rice and Other Dietry Components in Rural BengalHalder, Dipti January 2013 (has links)
This study investigates the risk of arsenic (As) exposure from staple diet to the communities in rural Bengal, even when they have been supplied with As safe drinking water. The results indicate that average accumulation of As in rice grain increases with decrease of grain size [extra-long slender (ELS): 0.04 mg kg-1; long slender (LS): 0.10 mg kg-1; medium slender (MS): 0.16 mg kg-1 and short bold (SB): 0.33 mg kg-1], however people living in the rural villages mostly prefer brown colored SB type of rice because of its lower cost. Among the vegetables generally consumed in rural villages, the accumulation of As is highest in the leafy type of vegetables (0.21 mg kg-1), compared to non-leafy (0.07 mg kg-1) and root vegetables (0.10 mg kg-1). Arsenic predominantly accumulates in rice (>90%) and vegetables (almost 100%) in inorganic species [As(III & V)]. The estimates of exposure via dietary and drinking water routes show that when people are consuming water with As concentration <10 μg L-1, the total daily intake of inorganic As (TDI-iAs) exceeds the previous provisional tolerable daily intake (PTDI) value of 2.1 μg day-1 kg-1 BW, recommended by World Health Organization (WHO) in 35% of the cases due to consumption of rice. Considerably high concentration of As in urine and saliva despite drinking of As safe water (<10 μg L-1) further supports that dietary intake of As, mainly through consumption of rice could be alternative pathway of As exposure among the population. When the level of As concentration in drinking water is above 10 μg L-1, the TDI-iAs exceeds the previous PTDI for all the participants. These results imply that when rice consumption is a significant contributor to the TDI-iAs, supplying water with As concentration at current national drinking water standard for India and Bangladesh (50 μg L-1) would place many people above the safety threshold of PTDI. When As concentration in drinking water exceeds 50 μg L-1 As exposure through drinking water largely predominates over the exposure through dietary intake. It is found that the consumption of vegetables in rural Bengal does not pose significant health threat to the population independently. It is also revealed that cooking of rice with high volume of As safe (<10 μg L-1) water can decrease both total and inorganic As content in cooked rice. However, the assessment of As exposure risk indicates that despite such lowering in As concentrations, still consumption of cooked rice is a significant pathway of As exposure to the population in rural Bengal. This study suggests that any effort to mitigate the As exposure of the villagers in Bengal must consider the risk of As exposure from rice consumption together with drinking water. / <p>QC 20130919</p> / EAECA-EURINDIA 2009-1665
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The effect of perennial grass species on forage growth and quality, etiolated growth, animal performance and economicsWard, Charlotte I. 13 February 2009 (has links)
A series of experiments were conducted during 2005 and 2006 to evaluate five perennial grass species for forage yield and quality, steer performance and grazing capacity, animal intake, plant energy reserves and economic return under grazed conditions. In 1999, two 0.8 ha replicates each of Paddock meadow bromegrass (<i>Bromus riparius</i>Rehm.), Carlton smooth bromegrass (<i>Bromus inermis</i>Leyss.) and AC Knowles hybrid bromegrass (<i>B. riparius</i> x <i>B. inermis</i>) were seeded. In 2003, two 0.8 ha replicates each of AC Goliath crested wheatgrass (<i>Agropyron cristatum </i> (L.) Gaertn.), hybrid bromegrass, and Courtenay tall fescue (<i>Festuca arundinacea </i> Schreb.) were seeded. A long established stand of crested wheatgrass acted as the control pasture. For 2003 established pastures, AC Goliath crested wheatgrass (7515 kg ha-1) had greater (P<0.05) cumulative dry matter yield than hybrid bromegrass (3136 kg ha-1) during the 2005 grazing season. Average (2005-2006) crude protein (CP) was greatest (P<0.05) for hybrid and smooth bromegrass for 1999 established pastures at start and middle of period one. Control pastures had the greatest (P<0.05) neutral detergent fiber (NDF) mid-grazing period. Over 2 years, smooth bromegrass had greater acid detergent fiber (ADF) (P<0.05) than control pastures at the end of the grazing period one. Average (2005-2006) in vitro organic matter digestibility (IVOMD) was greatest for hybrid and meadow bromegrass (P<0.05) at the start of grazing period one. Control pastures (129 g kg-1) had lower CP levels at the start of the 2005-2006 (average) grazing period 1 (P<0.05) compared to species seeded in 2003. Control and hybrid bromegrass pastures had the greatest NDF and ADF levels at the start of grazing period 1 (2005-2006 average) while tall fescue pastures had the lowest (P<0.05) NDF and ADF levels. Over 2 years, control pastures had the lowest IVOMD at start of grazing (P<0.05). In 2006, hybrid and smooth bromegrass had greater etiolated re-growth than control pastures (P<0.05). In 2006, grazed plants seeded in 1999 had greater (P<0.05) etiolated re-growth than ungrazed plants. For 2003 seeded grasses, crested wheatgrass produced greater (P<0.05) etiolated re-growth than tall fescue and control pastures. Average daily gain was similar (P>0.05) for all 1999 and 2003 seeded grasses. Overall, bromegrasses seeded in 1999 produced greater animal grazing days (AGD) than control pastures (P<0.05). Total beef production (TBP) was greater (P<0.05) for hybrid and meadow bromegrass compared to the control. All species seeded in 2003 produced greater AGD (P<0.05) compared to the control. Crested wheatgrass produced greater (P<0.05) TBP than the control over both years of the study. The C33:C32 alkane ratio estimated greater DMI (P<0.05) for hybrid bromegrass (9.9 kg d-1) and control pastures (9.6 kg d-1) compared to crested wheatgrass (6.8 kg d-1) or tall fescue (6.8 kg d-1) during period 1 in 2006. Over 2 years, net return to labor, equity and personal draw was greater (P<0.05) for hybrid bromegrass ($91.24 ha-1) compared to the control (-$54.32 ha-1). For 2003 seeded pastures, all pastures generated positive returns over 2 years. Crested wheatgrass ($92.49 ha-1) had greater net return than control pastures (-$54.32 ha-1) (P<0.05). Finally, the results of this grazing study indicate beef producers can manage these grasses during the summer grazing season and maintain high levels of animal performance and pasture production. This study has demonstrated that bromegrasses, crested wheatgrass and tall fescue could work well in a complementary grazing system.
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