The Virginia Tech crossbreeding program began in the fall of 2002 by mating Holstein and Jersey foundation females to Holstein and Jersey bulls to create HH, HJ, JH, and JJ breed groups (sire breed listed first). Collection of daily dry matter intakes (DMI) began in the fall of 2005 and continued through spring of 2008. DMI were measured for two weeks out of every six week period in first lactation on 44, 32, 29, and 13 HH, HJ, JH, and JJ cows. Daily milk and body weights and monthly milk components were collected. The National Research Council (NRC) DMI prediction equation was used across breed groups to investigate breed differences. DMI prediction equations were developed across breeds. Random regression model were used to predict energy consumed (TEC), energy needed for production, maintenance, and growth at every week of lactation (WOL). Energy balance (EB) was calculated at every WOL by subtracting energy for production, maintenance, growth, and pregnancy from TEC. Common health events were recorded if they occurred in the first 100 days of lactation. Logistic regression was used to analyze health disorder. The HJ and JH were not different from each other in any analyses. The NRC under-predicted DMI for HH and over-predicted DMI for HJ, JH, and JJ. There were significant breed differences in the prediction equations developed. Results indicated that breeds differ in DMI after accounting for production and body weights. The HH cows consumed more energy than HJ and JJ cows. The HH, HJ, and JJ were not different from each other for production but were different from JJ. The JH allocated less energy to maintenance than the HH. There were no breed differences for weeks required to reach positive EB, return to positive cumulative EB, or EB at week 21 of lactation. The HJ, JH, and JJ were more likely to have an incidence of mastitis than HH. The HJ and JH were less likely to have an incidence of metritis than HH. The results indicate breeds differ in DMI, and health diseases and evidence suggests differences in characterization of EB and warrants further investigation. / Ph. D.

Up to 80% of menopausal women suffer from hot flushes, consisting of a coordinated activation of heat loss mechanisms (sweating, cutaneous vasodilatation, etc.). Ovarian steroid withdrawal also leads to hypersecretion of gonadotropins (LH and FSH) and changes in body fat distribution. Because gonadotropin release, thermoregulation, and energy balance are hierarchically controlled by the hypothalamus, it is likely that changes in response to estrogen withdrawal are occurring at the level of the hypothalamus. The infundibular (arcuate) nucleus of the hypothalamus contains an estrogen-sensitive population of cells that co-express kisspeptin, neurokin B (NKB), and dynorphin ("KNDy neurons"). KNDy neurons have been proposed to be a site of estrogen negative feedback on gonadotropin release in multiple species because they are estrogen sensitive and respond to estrogen withdrawal with somatic hypertrophy and significant changes in gene expression. Because KNDy neurons project to known thermoregulatory centers in the hypothalamus (such as the median preoptic nucleus, MnPO), we also hypothesized that changes in thermoregulation were also a due to changes in KNDy neurons. Ovariectomized (OVX) rats also show disorders of thermoregulation, increased serum LH and FSH, and altered weight gain. Furthermore, OVX rats exhibit KNDy gene expression changes similar to changes seen in the human, making this model ideal to study the effects of estrogen withdrawal. We used a novel neurotoxin conjugate NK₃-SAP to ablate KNDy neurons in OVX female rats. We then observed core and tail skin temperatures, serum gonadotropin levels, and weight changes before and after replacement with 17β-estradiol. Next, we ablated NK3R-expressing neurons in the MnPO and monitored the thermoregulatory axis. Rats with KNDy-ablation did not exhibit the rise in LH and profound weight gain associated with ovariectomy. Furthermore, KNDy-ablated animals did not exhibit the chronic vasodilatation observed in OVX rats, providing the first evidence that KNDy neurons play a role in vasomotion. Rats with NK₃R cell-specific MnPO lesions also exhibited decreased activation of heat loss effectors. Together, these data demonstrate an important role for arcuate KNDy neurons in estrogen modulation of LH release and body weight, and demonstrate that NKB signaling is critical for activation of heat dissipation effectors.

Title: The Relationship between Moderate, Within Day Protein Intake and Energy Balance on Body Composition of Collegiate Sand Volleyball Players Background: Achieving an ideal body composition with relatively low fat mass and relatively high fat-free mass (FFM) is desirable for virtually all competitive athletes. Some studies suggest that protein intake, depending on quality, amount, and timing, may improve relative musculature by stimulating muscle protein synthesis, but some issues related to timing and amount of protein intake remain unclear. Current evidence suggests that frequent consumption of moderate amounts of protein is useful for muscle building. Purpose: The purpose of this study was to simultaneously assess energy balance and protein intake to determine if these factors are associated with body composition in a population of collegiate sand volleyball players. Methods: In a cross sectional, observational study, players completed a food intake and activity form for a 24-hour period to serve as the basis of energy balance and protein intake assessment. The assessment day was representative of a typical day during the regular training season. These data were entered into a software program providing total and hourly energy balance and nutrient content of the consumed foods. Athletes were measured for body composition via a multi-current bioelectrical impedance scale to predict weight, BMI, fat mass and fat free mass. Height was measured using a standard wall-mounted stadiometer. Data analyses included descriptive and frequency statistics, Spearman correlations and regression analyses. Results: Twelve women from the GSU sand volleyball team participated in the study using an IRB-approved protocol. The mean BMI was 22 kg/m2 (±3 kg/m2) and the mean body fat percentage was 18% (±7%). The mean protein intake for all participants was 132 grams (±52 g). Protein intake distribution was skewed, on average, toward the latter half of the day with approximately 19% of protein consumed in the morning and 34% consumed in the evening. The mean net energy balance at the end of the 24-hour assessment period was -404 (±385) kcal. Athletes, on average, spent 17 hours in a catabolic energy balance state (< 0 kcal). No significant correlation was found between energy balance per gram of protein consumption and body composition. However, regression analyses indicated that energy balance and protein variables explain a significant proportion (p=.037) of the variance in body fat percentage. Conclusions: Sand volleyball players in this study spent a high proportion of time in a negative energy balance, which may have compromised the potential benefit that frequent protein consumption may have had on FFM. Since both energy balance and protein explain a significant proportion of the variance in body composition, these athletes might benefit from improving within-day energy balance as a strategy for optimizing body composition.

The boreal forest forms a band that stretches across the continents of the northern hemisphere. Wildfire disturbances have helped transform this forest into stands of varying ages with varying soil drainage. It is well known that the boreal forest contributes greatly to the global water cycle, but less is known as to how variable these water fluxes are throughout the forest mosaic. Throughout the growing seasons of 2006 and 2007, meteorological measurements were taken during the growing season from three different aged black spruce stands near Thompson, MB. The stands that were burned in 1930 and 1964 each included upland and lowland sites with independent measurements. The stand burned in 1850 had measurements taken only from an upland site. Evapotranspiration (ET) was calculated from the residual energy after net radiation (Rn), sensible heat flux (H) and ground heat flux were measured. We sought to investigate whether ET varied with stand age and topographic location. Results indicate that there is a significant increase in Rn, H, and ET as forests age. ET levels range from being 4% to 19% lower for younger stands. It is assumed that the depth of the organic layer at older sites allows for mosses to more effectively wick up available moisture through capillary rise, and have higher transpiration levels. The larger tree density at the 1964 sites compared to the 1930 sites may account for a portion of the observed increase in ET for these ages. Differences in drainage between the 1930 and 1850 sites may also account for a portion of the increase in ET observed between these two ages. Wetland sites had H and ET that were significantly less than for the upland sites. ET rates were 11 to 20% higher at the upland sites than the wetland sites; part of this difference is thought to be due to the presence of larger trees, with an increased capacity to transpire water at upland sites. As the number of forest fires has been predicted to increase substantially in the future, the prospect of the boreal forest average stand age being younger would affect the boreal’s water and energy budgets. Our data helps to describe water and energy budgets for forest stands with different drainage capabilities, for stands between the ages of 45 and 160 years. This knowledge will be used to help predict the degree and speed of climate change that will be experienced in the boreal forest. / October 2008

Many recent studies on the relative costs and benefits of biofuels have raised the need for a detailed and rigorous analysis of the operations of a biorefinery that is focused on optimization. The current thesis concentrates on the design and optimization of plants for producing biodiesel and ethanol from cellulosic biomass. We have performed numerical simulations combined with systematic parametric analyses to investigate the effect of various parameters on the overall material and energy balances of each biorefinery. The efficiency of the simulated processes was investigated by introducing and/or estimating various metrics in order to select the more beneficial directions for process improvements. Particular emphasis has been paid on heat integration and the design of highly efficient combined heat and power (CHP) units that generate the steam and electricity needed for the purification of biofuels and their co-products. The first part of the thesis is focused on biodiesel production via transesterification of soybean oil with methanol, under alkali-catalyzed conditions. We have analyzed the performance of several reactor configurations in order to improve the conversion of the reversible transesterification reactions. The effect of the oil to alcohol ratio has also been extensively explored. Furthermore, the energy requirements of the simulated process have been rigorously calculated. Since biodiesel facilities can be used either for small-scale, distributed applications or for large-scale production, we have explored whether it is more energy efficient to burn the glycerol-rich stream in a combined heat and power (CHP) plant, or purify the glycerol and use it a feedstock for producing higher-value chemicals with further biotechnological processes. The second part of the thesis focuses on the production of cellulosic ethanol. Having developed the process model, a detailed parametric analysis was carried out to determine how the energy balances and overall efficiency of the biorefinery were influenced by changes in (a) the composition of the biomass feedstock, and (b) the conversion levels of the hydrolysis and fermentation stages. Furthermore, the requirements of the utility section of the ethanol plant were calculated. The utility section included a combined heat and power unit where by-product streams of the production process were utilized for energy generation. The parametric analysis indicated that these streams were in most cases an insufficient fuel source for meeting the energy requirements of the plant and thus, additional fuel was required (biomass, coal, or natural gas). The calculations of this section indicated a significant trade-off between ethanol production and external energy inputs, thus casting some doubt on the ultimate effectiveness of efforts to develop genetically modified energy crops (with high carbohydrate content) in order to maximize fuel production.

Introduction: Ballet dancers’ body weight and BMI have been shown to be below recommended levels, and total energy intake is often sustained at a level below the predicted energy requirement. Less is known about the ability of dancers to manage energy balance (EB) during the day, as energy requirements fluctuate as a result of periods of rest and intense activity. Compromised EB may result in decreased athletic performance, higher body fat percentage, and increased injury risk. Purpose: To assess within-day energy balance (WIDEB) during a typical training day in a group of pre-professional ballet dancers and dancers in the early years of professional careers, and to assess the relationship between inadequate EB and injury rates in these dancers. Methods: A two part assessment tool was developed to measure energy intake and energy expenditure hour by hour within a single 24 hour time period. Body mass index (BMI), resting energy expenditure, total day energy balance, and energy deficits > -400 kcal were also used in analysis. Participants were asked to document number of injuries incurred within the previous dance season, and how many days the injury resulted in one or more complete or partial sessions of time lost beyond the injury itself. Data analysis included descriptive statistics, t-tests, and Spearman’s correlation to evaluate relationships between EB and injury rates. Results: Data were collected from 21 (5 males, 16 females) pre-professional and professional ballet dancers from the Atlanta Ballet. Average BMI was 21.9 ±1.4 for male dancers (MD) and 19.1 ±1.0 for female dancers (FD). Negative energy balance (EB) was found at hour 24 in 90.5% participants. Average energy intake for all dancers was 2,382 kcal (± 921) and the average predicted energy expenditure was 3,317 kcal (± 592). Mean EB at hour 24 for all participants was -781.2 (±689.4). The average day EB for males was -223.6 (±629.7) and -1156.9 (±582.5) for females. The largest energy deficits (>900 kcal) compared to estimated expenditures were found between the hours 17 and 20. Participants spent an average of 660.0 (±192.6) minutes per day in negative EB > - 400 kcal. Total group (TG) injury days and energy deficit data (number of minutes > - 400 kcal) were not significantly correlated. Number of minutes > - 400 kcal and number of injuries reported per dancer were correlated (r = -0.44 P = 0.046). MD (n = 5) injury days were significantly associated with EB at hours 1 through 7 (r = 0.90 P = 0.37). MD total number of times injured was associated with EB at hours 1 through 7 (r = 0.89 P = 0.04). A significant association was found in FD between number of times injured and deficits > - 400 kcal. Conclusions: Ballet dancers have significant energy deficits during a typical training day therefore increasing their risk for injuries. Nutrition education would be a key component of an injury prevention program for dancers.

This thesis defines the Energy Balance Load ( BL E ) as the difference between the heating requirements plus the electric gains in the building and the cooling coil loads. It then applies a first law energy balance in conjunction with the concepts of analytical redundancy (AR) and trend checking to demonstrate that measured values of BL E can be compared with the simulated characteristic ambient temperature-based BL E to serve as a useful tool to identify bad data. Uncertainty and sensitivity analysis are introduced to analyze the impact of each building or system parameter to the simulated values of BL E . A Visual Basic for Application (VBA) program has been developed through this research work, which applies the methodology illustrated in this thesis to automatically prescreen the measured building energy consumption data with the inputs of several key parameters. Through case studies of six on-campus buildings, the methodology and the program successfully identified monitored consumption data that appears to be erroneous, which may result from incorrect scale factors of the sensors and the operational changes to the building that may enormously affect the key parameters as the simulation inputs. Finally, suggestions are given for the on-line diagnostics of sensor signals.

Obesity is a known risk factor for many types of cancer including pancreatic. Calorie restriction (CR), an anti-obesity diet regimen, has potent anticancer effects that may be mediated through its ability to reduce serum metabolic hormones and protumorigenic cytokines such as insulin-like growth factor (IGF)-1. IGF-1 is a metabolic hormone responsive to nutrient status that activates the inflammatory, cancer-related pathway, nuclear factor (NF)-[kappa]B. For this report, we tested the hypothesis that CR, via regulation of IGF-1, inhibits pancreatic tumor cell growth through modulation of NF-kB activation and protumorigenic gene expression. Male athymic nude mice were randomized to either a control diet consumed ad libitum (n=15) or a 30% CR diet (n=15) for 17 weeks, at which time, mice were injected with human pancreatic cancer cells (MiaPaca) and tumor growth was monitored for 6 weeks. Translocation of p65, a regulatory element of NF-[kappa]B, and expression of its downstream gene targets were analyzed in excised tumors. CR mice weighed less, (p<0.05), and had smaller tumors (p=0.022) relative to controls. Tumors from CR mice, relative to controls, demonstrated significant decreases in NF-[kappa]B downstream genes CCND1, RELA, Survivin, VEGF, and XIAP. These findings parallel our previous studies in pancreatic tumors from mouse origin, and suggest that the inhibitory effects of CR on MiaPaca pancreatic tumor growth are associated with decreased NF-kB activation. / text

The boreal forest forms a band that stretches across the continents of the northern hemisphere. Wildfire disturbances have helped transform this forest into stands of varying ages with varying soil drainage. It is well known that the boreal forest contributes greatly to the global water cycle, but less is known as to how variable these water fluxes are throughout the forest mosaic. Throughout the growing seasons of 2006 and 2007, meteorological measurements were taken during the growing season from three different aged black spruce stands near Thompson, MB. The stands that were burned in 1930 and 1964 each included upland and lowland sites with independent measurements. The stand burned in 1850 had measurements taken only from an upland site. Evapotranspiration (ET) was calculated from the residual energy after net radiation (Rn), sensible heat flux (H) and ground heat flux were measured. We sought to investigate whether ET varied with stand age and topographic location. Results indicate that there is a significant increase in Rn, H, and ET as forests age. ET levels range from being 4% to 19% lower for younger stands. It is assumed that the depth of the organic layer at older sites allows for mosses to more effectively wick up available moisture through capillary rise, and have higher transpiration levels. The larger tree density at the 1964 sites compared to the 1930 sites may account for a portion of the observed increase in ET for these ages. Differences in drainage between the 1930 and 1850 sites may also account for a portion of the increase in ET observed between these two ages. Wetland sites had H and ET that were significantly less than for the upland sites. ET rates were 11 to 20% higher at the upland sites than the wetland sites; part of this difference is thought to be due to the presence of larger trees, with an increased capacity to transpire water at upland sites. As the number of forest fires has been predicted to increase substantially in the future, the prospect of the boreal forest average stand age being younger would affect the boreal’s water and energy budgets. Our data helps to describe water and energy budgets for forest stands with different drainage capabilities, for stands between the ages of 45 and 160 years. This knowledge will be used to help predict the degree and speed of climate change that will be experienced in the boreal forest.

No description available.