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Title: Relationship of Energy Balance and Body Composition in Elite Female Gymnasts Background: Studies suggest that athletes participating in weight-specific and appearance-based sports, including gymnasts, are at risk for developing negative energy balance both during and at the end of the day. A prolonged state of negative energy balance has been associated with lower fat-free mass, higher fat mass, and lower bone mineral density. Energy balance is defined as energy in minus energy out, and has been viewed in the past as a static, 24-hour system that begins anew each day. This study examined the relationship of energy balance and body composition (lean body mass, fat mass, body fat percent) and bone mineral density. Studies evaluating the relationship between energy balance and body composition have been conducted in the past, but few have taken into consideration hourly energy balance and the effects of multiple time periods of energy deficit of < -400kcal. Purpose: The purpose of this study was to assess the relationship between energy balance and body composition in female gymnasts. Methods: This study utilized a secondary analysis of existing data, and included 23 female elite, nationally ranked, gymnasts. Participants were included in this analysis if they had completed three-day food and activity records and had full body DEXA scans. The food and activity records were analyzed using NutriTiming®, which predicts RMR via the Harris-Benedict equation, uses a MET-based relative intensity activity scale, and accesses the USDA Nutrient Database for Standard Reference, Release 26. NutriTiming provides both 24-hour and hourly energy balance values. Original data were collected as part of a study conducted at Georgia State University in 1993 that had received IRB-approval. The current study also received IRB approval. Results: Subject characteristics (mean ± SD) were: age (15.1 ±1. 58 years), height (151.3 ±7.7cm), and weight (45.63 ±8. 31kg). Average energy intake during the three days examined was 1375 kcal (±405), and the average predicted energy expenditure was 2430 kcal (± 298), for an energy balance of -1053 (± -438). Subjects were in a negative energy balance state the majority of the days analyzed. Spearman rho analysis found significant negative correlations between kcal consumed per kg bodyweight and body fat percent (r= -0.603, p=0.002), bone mineral density (r= -0.577, p=0.004), fat mass (r= -0.556, p=0.006), lean body mass (r= -0.466, p=0.025), lean body to height ratio (r= -0.466, p=0.025), and weight (r=-0.633, p=0.001). A significant amount of variance (R2= 0.435; SEE= ±0.05919, p=0.001) was explained in bone mineral density (dependent variable) with fat mass (independent variable). Conclusion: The associations in this study are consistent with previous studies evaluating the relationships between energy balance deficits and body composition, indicating that poor energy balance is associated with lower lean and higher fat mass. Lean body mass, fat mass, and BMD were positively correlated with age, but 24-hour energy balance was negatively correlated with age (r= -0.484; p=0.019), suggesting that, although growing, subjects were consuming less energy with increasing age.

In 1973 and again in 1979 oil prices increased dramatically forcing many developed and developing nations to begin programmes of energy conservation in different areas of industry. I.R Iran as an oil producing and exporting country never felt the full effect of these global oil shortages. Therefore, it was one of the few countries in the world not to invest much time or money in the study of energy conservation. Recent studies have shown that in less than two decades domestic oil consumption and Iranian oil production will balance. When this happens Iran will lose its revenue from oil exports, upon which it is dependent for foreign currency, and may even have to begin to import energy. Therefore, Iran is not only behind most countries in the investigation of energy conservation technology but is facing severe shortages. This thesis studies Iran's energy production, consumption, and outlines the possibilities for energy conservation in Iran. Chapters 1 through 4 of this work introduce Iran, its geography and location and also provide a synopsis of its current energy situation. Chapter 2 explains Iran's energy balance, outlining the production and consumption of the different fuels used in Iran. Chapter 3 looks at energy demand forecasts as well as price and income elasticities. It is this chapter that highlights Iran's impending energy crisis. Chapter 4 discusses the general energy efficiency potential and obstacles to that energy efficiency in Iran. This chapter touches on the subjects of fuel prices and the institutions set up to control energy. Chapter 5 looks at energy conservation in Industry. It is divided into two main parts; first, a general look at industrial energy conservation techniques and practices in developed and developing nations; second, a specific look at energy conservation in Iranian industry. The latter section is itself divided into three parts; one, an energy audit of the National Industries Organization; two, energy conservation in the cement industry with a specific case study done at the Tehran cement factory; and, three, a general look at energy conservation in the glass industry, with a specific case study done at the Ghazvin Glass Company. Chapter 6 examines energy conservation in Transportation. It opens with a general overview of technical and managerial aspects of energy conservation in transportation in general around the world. Next, it discusses potential for energy conservation related to transportation in Iran. Chapter 7 discusses energy conservation in Mining. There has been very little work done on this subject, especially when compared to the information available on energy conservation in transportation and industry. Therefore, a special study was carried out in this field. This study identified a number of possible areas of energy conservation in mining. A separate section of Chapter 7 describes the Iranian mining sector and notes that its growth will necessitate quite a lot of work on energy conservation in that sector. Chapters 8 and 9 examine Employment and the Environmental aspects of energy conservation. First the subjects are examined in a general way and then they are discussed specifically for the case of Iran. Chapter 10 contains the conclusion and recommendations for every chapter of this work. The study of energy production and use in Iran which is described and discussed in this thesis is related to recommended actions for the future. It is shown that energy conservation can play an important role in the Iranian economy. Not only can it have positive environmental and employment effects, but it can delay the time when Iran ceases to be a net exporter of oil.

Background: Over the past decade obesity has doubled in children aged 6-11 and tripled among adolescents aged 12-19. One trend that has coincided with this increased obesity prevalence is decreased meal frequency, which may impact blood sugar, meal size, cortisol release, insulin release, and appetite controls that include the release of leptin and ghrelin. Ultimately, these changes may result in a simultaneous lowering of the metabolic (i.e., fat-free) mass and a rising of the fat mass. Purpose: To assess food/beverage intake in a way that would determine if large deviations in energy balance (EB) during the day were related to body fat percent (BF%). Methods: Using an IRB-approved protocol, male and female children were assessed using NutriTiming® (NutriTiming LLC, 2011) software, which simultaneously assesses energy intake from consumed foods and beverages and energy expenditure from activities with different intensities. A 24-hour recall questionnaire and interview, with at least one parent present, was used to obtain data, which represented a typical school day. BF% was assessed using an 8-mode bioelectrical impedance segmental body composition analyzer (Tanita, Model BC-418). Statistical analysis was performed with SPSS (ver. 18). Results: A total of 16 children ranging in age from 8-14 years were interviewed. Due to incomplete data on 4 subjects, 12 subjects (6 boys; 6 girls ranging in age from 9-14 years; mean=11.41 ± 1.5) were included in the data analysis. Energy intakes averaged 1,984 ± 510 kcal; and energy expenditure averaged 1,689 ± 351 kcal. Average BF% was 24.3 ± 4.9. Using Spearman correlation and independent group t-test (with the mean energy balance as the cut-point) traditional end-of-day energy balance (24-hr energy in vs. 24-hr energy out) was not statistically associated with body fat %, and there was no difference in BF% between those above and below the end-of-day EB mean. However, more hours spent in an energy surplus (EB > 0) was significantly associated with lower body fat % (r=-0.914; PP

Background: The customary mechanism for assessing weight change involves an assessment of the imbalance in the energy consumed vs. the energy expended. This energy balance ratio is commonly assessed in 24-hour periods, but this strategy fails to account for the timing of macronutrient intake and within-day fluctuations in energy balance, which have an influence on body composition and, ultimately, weight. Hourly fluctuations in energy balance provides information on the time spent in a catabolic state and time spent in an anabolic state, which is not possible with a 24-hour energy balance assessment. Measuring hourly energy balance to optimize absorption and storage of specific nutrients may be a practical strategy for obese individuals to improve body composition. Purpose: The purpose of this study was to observe current dietary habits and assess hourly energy balance of college students with different BMI categories (i.e., below and above a BMI of 30) to determine if there are differences between body composition and hours spent in different energy balance states. Methods: The subjects completed a four-day diet and physical activity record from which energy intake and energy expenditures from a relative intensity activity scale was predicted linked to MET values. After completing the record, subject weight, height, % body fat and fat free mass was assessed using a multi-frequency bioelectrical impedance segmental body composition analyzer. Results: Data were analyzed from a total of 17 college students (9 men and 8 women) ranging from 20-28 years old (mean age 23 ± 2.6). Predicted energy intake averaged 2237.3 ± 749.3 kcals/d and predicted energy expenditure averaged 2941.7 ± 552.7 kcals/d. The average body fat % of the subjects was 27.1 ± 11.6% and the average BMI of the subjects 28.8 ± 5.8. Using an Independent Samples T-Test, eight subjects with a BMI ≥ 30 spent more time in hours high deficit (< -400 kcals Energy Balance) when compared to nine subjects with a BMI < 30. Nine subjects with a BMI < 30 spent more time in ±400 kcal energy balance. Using a Spearman Rho correlation, body fat % was positively correlated to hours high deficit (p ≤ 0.01) and negatively correlated to hours in ±400 kcal energy balance (p ≤ 0.01). Analysis of men and women found that body fat % of men was not significantly associated to any energy balance variables. While not significant, there was a trend toward a positive correlation between body fat % and hours high deficit (p=0.065) and a negative correlation between body fat % and hours in ±400 kcal energy balance (p=0.065). In women, subjects who spent more time in high energy deficit (< -400 kcals Energy Balance) had higher body fat % (p ≤ 0.05). Subjects who spent more hours in optimum energy balance (± 400 kcal Energy Balance) had lower body fat % (p ≤ 0.05). Conclusions: These data suggest that spending long periods of time in an energy deficit is correlated with higher body fat % and higher BMI in college students. Particularly for women, it may be beneficial for body composition to avoid long periods of time in energy deficit and strive to remain in or near ±400 kcal energy balance. College students may be especially prone to extreme deficits in energy balance because of unpredictable schedules and frequent meal skipping. Recommendations for avoiding large energy deficits throughout the day may be beneficial for this population.

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Pancreatic cancer is the fourth leading cause of cancer death in the United States, with a five-year survival rate under 5%. Given the disease’s deadliness, increasing our understanding of the molecular nature of the pancreatic cancer is key to developing more effective preventive measures and treatments. Dietary energy restriction (DER) has been shown to have potent anticancer effects in pancreatic cancer, but the mechanism of action has yet to be completely elucidated. Here we investigate the potential of altered microRNA expression as a mechanism by which DER exerts its anticancer effect. Using the Exiqon microRNA Array, we identified several microRNAs of interest for further study. This includes microRNA (mir) 669c, a known regulator of glutathione-S transferases (linked to carcinogen metabolism and oxidative stress) that increases with age. To our knowledge, this is the first exploration of the effects of DER (which is known to suppress oxidative stress and other processes associated with aging and cancer) on microRNA expression. These findings may provide the initial steps towards identifying novel targets for pancreatic cancer prevention or treatment. / text

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Nowadays, energy is becoming more and more important. With the development of society, the demand of energy is also increasing correspondingly. There is 22% of the total energy which is used in building part. A more effective and sustainable energy system becomes necessary due to increasing energy prices and demand. The aim of this thesis is to make an energy survey of this building, evaluating different sources of energy supply and losses in this building. By evaluating, a better thermal comfort is expectedly achieved when having examinations, and a possible saving method is also expected in order to reduce the cost of this system.  In this project, the building is located in University of Gävle which is surveyed. It has 2 floors. The first floor is underground as a basement. An examination room is included in the second floor. There are a space heating system and heating recovery system ventilation in this examination building. At first step of analysis, the data of construction, ventilation, district heating and hot tap water were arranged by Mr. Magnus. Secondly, an energy balance had been done, and it helped to make energy input and output more clearly. In energy supply part, the solar radiation is 22.4MWh, the internal heat from people is 1.95MWh, the internal heat from equipment is 5.63MWh and district heating is 184MWh. In energy losses part, the transmission loss is 165MWh, the mechanical ventilation loss is 38.3MWh, the infiltration loss is 8.38MWh and the hot tap water is 2.09MWh. Thirdly, results of calculations were analyzed. At last, the optimization methods were given to save energy. The optimization methods were changing type of windows and improving indoor temperature which influenced the transmission loss part. Another method was reducing operating time of the ventilation system. Through these optimizing methods, the total energy use is reduced from 214MWh to 179MWh, and district heating is reduced from 184MWh to 149MWh. District heating of this building is supplied by Gävle Energi company, which is able to save 20% cost by these optimizing methods. According to the investment analysis, 19thousand SEK energy is saved per annum.

In the summer of 2008 (June 2nd September 19th) detailed measurements of meteorological conditions and glacier surface properties were conducted in the Belcher Glacier catchment (718 km2), Devon Island Ice Cap, Nunavut, Canada. These measurements were used to force and validate a distributed surface energy balance and sub-surface snow model capable of calculating surface ablation rates and meltwater runoff. This study represents a contribution to the International Polar Year (IPY) Glaciodyn project, whose overall aim is to examine the role of hydrology and ice dynamics in the response of marine-terminating glaciers in the Arctic to climate change. Spatially-averaged total water equivalent (w.e.) ablation was 677 mm w.e., and total predicted runoff during the 2008 summer was 3.9 x 108 m3. Net radiation (87%) was the main source of energy over the study period, followed by the sensible heat flux (13%). Net longwave radiation and the latent heat flux represented an overall energy loss from the surface. Modelled melt season duration lasted from June 17th August 15th, and the majority of ablation occurred in two main periods, from June 26th July 18th, and from July 27th to August 14th. Snowfall and lower air temperatures limited ablation between these dates and after August 15th. Ice exposure at elevations below 1000 m occurred by July 1st. Periods of high ablation rates were associated with positive air temperatures and high net shortwave radiation receipts, and with near surface air temperature gradients that were shallow or inverted (i.e. higher air temperatures at higher elevations). Periods of minimum ablation rates occurred when net shortwave radiation receipts were reduced (e.g. following summer snowfall) and when air temperatures were negative. The largest changes in both the net surface energy balance and ablation rates were linked to changes in surface albedo associated with (i) snowpack removal and ice exposure, and (ii) summer snowfall events. Modelled time series of runoff from individual sub-catchments within the Belcher catchment will be used to force a coupled hydrology and ice flow dynamics model of the Belcher Glacier that will be used to investigate the dynamic response of tidewater-terminating glaciers to surface hydrological forcing.