Background: Daily nutrient/energy intakes are typically evaluated as a total 24-hour intake rather than as the amounts consumed per eating opportunity. Evidence suggests that smaller, frequent meals containing persistent levels of energy and protein may be more beneficial for achieving a lower body fat and higher fat-free mass than equal intakes consumed in larger and less frequent amounts. This may be due to a better-maintained energy balance (EB) that is achieved with smaller and more frequent intakes. Objective: The objective of this study was to determine the relationship between hourly EB and protein intake with body composition. Methods: Using a software program that provides hourly and 24-hour energy and nutrient intakes and hourly energy expenditures, a secondary analysis of previously collected 3-day food diaries was used to examine the relationship between hourly EB and body composition. The food and activity diaries provided information on time of food/beverage consumption and hourly energy expenditure, enabling an hourly analysis of EB. Body composition, including fat mass, fat-free mass, and bone density were examined via dual-energy x-ray absorptiometry. SPSS was used for statistical analysis, and included descriptive statistics, correlational analyses, t-tests, and regression analyses. Results: Existing data from elite female gymnasts (N=40) were assessed using an IRB-approved protocol. Higher protein consumption was significantly associated with lower bone mineral density (BMD) in the gymnasts at the arms (r= -0.535; p< 0.001), legs (r= 0.0523; p= 0.001), trunk(r= -0.517; p=0.001), spine (r= -0.472; p=0.002), and pelvis (r= -0.539; p< 0.001). Other dietary factors assessing energy and protein intakes were not significantly associated with body composition. The assessed gymnasts spent the majority of the day in hourly energy balance deficits exceeding -400 kcal. A t-test comparing subjects with higher (n=22) vs. lower (n=18) fat-free mass (FFM), using the statistical mean as the cut point, found that higher protein intakes were significantly associated with lower FFM (p=.007). Subjects with more hours spent in an EB surplus had significantly higher FFM/kg (p=.008) and lower body fat % (p=.008). Conclusion: These findings suggest that higher protein intakes may compromise BMD, a finding likely exacerbated by the long periods of time spent in EB deficits. More hours in an EB surplus was associated with positive outcomes, including higher FFM/kg and lower body fat percent. These data suggest that higher protein intakes may be consumed by gymnasts with the greatest EB deficits, perhaps as a way of minimizing (unsuccessfully) weight and fat-mass. As virtually all hours of the assessed groups were in an EB deficit, it is possible that consumed protein was used to satisfy energy needs rather than being used anabolically to support or enlarge the muscle mass. Future studies should consider addressing this issue, perhaps by assessing more heterogeneous groups where at least a proportion of the population sustains a reasonably good EB during the assessment period.

Title: Within-Day Energy Balance and Protein Intake Affect Body Composition in Physically Active Young Adult Females Background: Past studies suggest that individuals who eat smaller, more frequent meals are at a metabolic advantage when compared to those who eat larger, less frequent isocaloric meals. Studies also suggest that consumption of small amounts (~ 20 to 30 g) of protein evenly distributed during the day, may be a superior strategy for satisfying the protein requirement and improving muscle protein synthesis. It was, therefore, the purpose of this study was to assess the relationship between body composition and the distributed consumption of energy and protein in physically active young adult females. Methods: Using an IRB approved protocol, physically active female volunteers were measured for height using a standard wall mount stadiometer; body composition and weight were measured using a multi-current 8-mode segmental bioelectrical impedance device (Tanita, Arlington Heights, Illinois USA, Model BC-418). The volunteers kept a food and activity journal for one day, which was assessed to determine hourly energy balance and hourly protein intake. Exertion was assessed using a relative intensity activity MET value scale that produces multiples of resting energy expenditure, which was predicted using the Harris-Benedict equation. Results: The 28 females who volunteered for this study ranged in age from 19-24 years. Significant inverse associations were found between protein (grams/kg) consumption and fat mass (r=-0.42; p=0.026); and FFM and the ratio of protein to energy balance at 4pm (r=-0.376; p=0.049). There was a significant positive association between FFM and the ratio of protein to energy balance at 12pm (r=0.390; p=0.040) and 9pm (r= 0.379; p=0.047). There was also a significant positive association between the ratio of FFM to height and the ratio of protein to energy balance at 12 pm (r=0.423; p=0.025). There was a significant association between highest daily peak energy balance and FFM to height ratio (r=0.402; p=0.034). Regression analysis determined that independent EB and protein variables could be used to predict the dependent variable FFM to Height ratio (r=.727; p=0.019). Conclusions: These findings demonstrate a significant positive association between highest daily EB and FFM to height ratio. The results also suggest that higher protein consumption per kg is inversely associated with fat mass. Similarly, when protein is consumed when in ±400 kcal energy balance, is associated with higher FFM. Additionally, energy balance and protein variables can be used to predict FFM to height ratio using a regression equation that accounts for 52.9% of variance. These data indicate that subjects spent far more hours in an energy balance deficit than surplus, making it difficult to assess the impact of protein intake distribution on body composition. It does appear that, from a relatively small subsample (n=28) who did achieve a positive within-day energy balance and adequate protein intake, consumption of protein while in good energy balance may help physically active adult females achieve a body composition that is low in fat mass and high in lean muscle mass.

Observational and modelling studies show that the warming of the Arctic is leading to shrub expansion. This shift in vegetation cover is expected to significantly alter the distribution of snow across the landscape and the interactions between the land surface and the atmosphere. Shrubs capture wind-blown snow, increasing snow depth and decreasing winter water loss through sublimation, and bend beneath the weight of snow, affecting albedo. Snow is highly insulative and affects the soil hydrological and thermal properties. Therefore, as the snow-vegetation-soil interactions is expected to be at the core of feedback loops leading to further shrub expansion, there is a need for models to be able to simulate these processes accurately. Initially using the community land surface model JULES (Joint UK Land Environment Simulator) this study investigates the effects of shrub-tundra on snow and runoff. Alternative formulations of soil processes are proposed, which are better adapted to the representation of subgrid heterogeneity in cold regions than the current model formulation, and evaluated over the Abisko and Torne-Kalix river basins. In addition, a high resolution shrub bending model, which calculates the exposed winter shrub fraction, is developed and parameterised for use alongside the snow cover parameterisation in JULES in order to provide a better representation of shrub-specific processes. This revised JULES more than doubles the efficiency coefficient and halfs the negative bias between modelled and observed runoff in the shrub-tundra Abisko basin. However, the current structure of the model is found to be inadequate for use in investigating the effect of shrub-tundra expansion because it calculates a single energy balance for the snow-free and the snow-covered areas. To address this issue, a distributed three-source (snow-shrub-ground) model (D3SM) is developed. D3SM is evaluated against snow and energy ux measurements from a shrub-tundra basin in the Yukon, Canada, and is found to reproduce snowmelt energetics well. The effects of shrub expansion on the energy balance of the basin during snowmelt are then investigated by increasing the vegetation fraction and canopy height of the current shrub distribution, which is found to be positively correlated with topography. D3SM shows that the most significant effects of shrub expansion in the basin are to reduce the spatial variability of snow depth and to increase the sensible heat flux from the surface to the atmosphere.

Changes in large-scale vegetation structure triggered by processes such as deforestation, wildfires, and tree die-off alter surface structure, energy balance, and associated albedo-all critical for land surface models. Characterizing these properties usually requires long-term data, precluding characterization of rapid vegetation changes such as those increasingly occurring in the Anthropocene. Consequently, the characterization of rapid events is limited and only possible in a few specific areas. We use a campaign approach to characterize surface properties associated with vegetation structure. In our approach, a profiling LiDAR and hemispherical image analyses quantify vegetation structure and a portable mast instrumented with a net radiometer, wind-humidity-temperature stations in a vertical profile, and soil temperature-heat flux characterize surface properties. We illustrate the application of our approach in two forest types (boreal and semiarid) with disturbance-induced tree loss. Our prototype characterizes major structural changes associated with tree loss, changes in vertical wind profiles, surface roughness energy balance partitioning, a proxy for NDVI (Normalized Differential Vegetation Index), and albedo. Multi-day albedo estimates, which differed between control and disturbed areas, were similar to tower-based multiyear characterizations, highlighting the utility and potential of the campaign approach. Our prototype provides general characterization of surface and boundary-layer properties relevant for land surface models, strategically enabling preliminary characterization of rapid vegetation disturbance events.

Challenges surrounding energy have gained increased attention, which is not least reflected in the 2030 Agenda for Sustainable Development and the Sustainable Development Goals (SDGs). Energy issues have also become a pressing matter for most countries in the last decades. The reasons for this are not only related to the effects of the emission of greenhouse gases (GHG) from fossil fuels and their impact in climate change, but also span through other issues such as security of energy supply with geopolitical considerations and competitiveness of industry. To address these issues, a collection of public policies ranging from the international to local levels have been implemented. Sweden has historically had lower energy prices than its European counterparts, which has resulted in its industry having a relatively higher share of electricity in the total energy use by industry. The share of electricity accounts for 35% of total energy use in Swedish industry. This has led to efficiency measures being overlooked by industry, and the pulp and paper industry is by far the biggest energy user, with a share of 51% of the total energy use by industry. The variation of energy prices, and particularly electricity prices have obvious implications on the competitiveness of this sector. Production of biogas in pulp and paper mills has been gaining attention, and is now the target of an increasing number of scientific studies. The interest for this industry is not only related to security of energy supply and the environmental performance of the biogas itself, but there are also considerations regarding the biogas plant as an alternative to treat the large flows of wastewaters and other waste stream in this sector. There is an estimated biogas production potential of 1 TWh within this industry in Sweden, which accounts for 60% of the current biogas production in the country. Pulp and paper mills commonly rely on aerated biological treatment to deal with waste streams with high organic content This biological process has a high energy demand, and the integration of an anaerobic treatment, along with the use of the biogas for heat and electricity can yield a net positive energy recovery for the combined plant. This project analyses the current energy and material performance of an anaerobic biological treatment combined with an aerobic biological treatment in a recycled board mill. The anaerobic treatment is performed upstream of the aerobic one and removes most of the chemical oxygen demand of the wastewater. Energy and material balances for the plant are presented, and a comparison of the wastewater treatment plant running before and after the start-up of the biogas plant is made. The plant operation with the anaerobic digestion has shown an increased energy use of 9.4% coupled to an increased flow of wastewater of 7.7%. The average biogas production is 72 Nm³/h, which accounts for 440 kWh and is currently being flared. The introduction of AD has largely decrease the organic load in the aerobic treatment, by nearly 50%. This project ends with an optimisation model implemented with the optimisation tool reMIND to investigate potential optimisation strategies for the operation of the combined plant. The model has shown to be adequate to describe electricity use with mean error below 10%. For the biogas production, the mean error was of 16%.

During late adolescence and the transition to college, students often experience weight increases and significant lifestyle changes including the adoption of unhealthy eating habits and decreased physical activity levels. To address this concern, a science-based, interactive course, designed from a framework of behavioral theories was developed to target improvements in energy balance knowledge and determinants of dietary and physical activity behaviors. The objective of this study was to assess the effectiveness of this course using a comparison group pre-test/post-test design. Thirty-three undergraduate students, ages 18-25, participated in the course, while twenty-six students served as controls. Paired samples t-tests compared pre- to post- responses to knowledge assessments and self-perception surveys. Independent samples t-tests compared mean changes between the intervention and control group. Course evaluations were reviewed to determine to what degree behavioral strategies were perceived to influence student motivation to eat a healthy diet and engage in the recommended amount of physical activity. Significant increases were observed in energy balance knowledge (P < .001) and perceived behavioral control (P = .004) towards eating a healthy diet in the intervention group when compared to the control group. Diet and physical activity recalls and analyses were perceived by students to have the greatest influence on their motivation/ability to engage in the targeted behaviors. We conclude that an online, interactive, science-based energy balance course developed from behavioral theories can be effective at improving energy balance knowledge and dietary perceived behavioral control in a college population.

Cross-sectional evidence associates breakfast omission with negative health outcomes. The present work aimed to examine if these cross-sectional associations have a causal component, by conducting randomised control trials in healthy humans. It was established using lean individuals that there are divergent hormonal responses to morning feeding and fasting, although increased energy intake at lunch following fasting incompletely compensated for breakfast intake. Hormonal and subjective appetite responses in the afternoon did not consistently provide evidence for increased hunger following fasting. In the same participants assigned to a 6-week free-living intervention of either 700 kcal pre 11:00 or fasting until 12:00 daily, it was found that energy intake was greater in those assigned breakfast consumption, but that physical activity was also greater than those fasting. Cardiovascular risk factors and measures of metabolic control were largely unaffected by either intervention. There was no adaptation of acute metabolic/hormonal responses to feeding following either intervention. In obese individuals, similar patterns of results were obtained for the hormonal and metabolic responses to acute feeding and fasting, but with no compensation for breakfast intake at lunch. Results from the free-living intervention demonstrated no difference in energy intake between groups or physical activity over the entire day, but greater energy expenditure during the morning in those consuming breakfast. Markers of cardiovascular health and metabolic control were generally not differently affected by either intervention. Neither intervention caused adaptation of the acute hormonal and metabolic responses to feeding. In summary, acute morning fasting does not cause complete compensation for breakfast intake at lunch, or result in greater hunger throughout the afternoon. Daily morning fasting does not affect acute responses to feeding or cause increased energy intake or weight gain relative to self-selected breakfast consumption, but seems to limit physical activity in lean, and to a lesser extent, in obese individuals.

<p>The energy audit is a very interesting and complex work. The building energy audit is defined as a process to evaluate where the energy used in the building structure and to identify the opportunities of reduce energy consumptions. In this paper, it is a first time detailed study of energy audit for me. In this research, the object is to find is it necessary to improve the ventilation systems. So the first step is to estimate how much energy consumed in the building and to find out the saving potential.The major mission in this thesis is that to make a basic energy audit which is include the heat losses from the building and the heat supply in the building. The major heat losses are transmission losses, ventilation losses, heat losses from hot tap water and infiltration losses. In this project the first three types of heat losses could be find out by some useful methods but the infiltration losses is hard to measure. On the other side, the heat supply are composed by district heating , free heating from people inside, free heating from electricity applications and sun irradiation.To make an accurate and complete energy audit is essential for finding out where the energy consumption could be reduced. And this is what I am going to do in this thesis work.</p>

Structural change in a two-sector model of the climate and the economy introduces issues concerning substitutability among goods in a two-sector economic growth model where emissions from fossil fuels give rise to a climate externality. Substitution is modeled using a CES-production function where the intermediate inputs differ only in their technologies and the way they are affected by the climate externality. I derive a simple formula for optimal taxes and resource allocation over time and highlight model sensitivity w.r.t the elasticity of substitution and distribution parameters. Energy Balance Climate Models and General Equilibrium Optimal Mitigation Policies  develops a one-dimensional energy balance climate model with heat diffusion and anthropogenic forcing across latitudes driven by global fossil fuel use coupled to an economic growth model. Our results suggest that if the implementation of international transfers across latitudes are not possible or costly, then optimal taxes are in general spatially non-uniform and may be lower at poorer latitudes. Energy Balance Climate Models, Damage Reservoirs and the Time Profile of Climate Change Policy explores optimal mitigation policies through the lens of a latitude dependent energy balance climate model coupled to an economic growth model. We associate the movement of an endogenous polar ice cap with the idea of a damage reservoir being a finite source of climate related damages affecting the economy. The analysis shows that the introduction of damage reservoirs  can generate multiple steady states and Skiba points. Assessing Sustainable Development in a DICE World investigates a method for assessing sustainable development under climate change in the Dynamic Integrated model of Climate and the Economy (DICE-2007 model). The analysis shows that the sustainability measure is highly sensitive to the calibration of the inter-temporal elasticity parameter and discount rate of the social welfare function.

Background: Past studies suggest that inadequate energy intake (EI) is directly related to menstrual dysfunction (MD) in active females. Inadequate EI causes activation of the hypothalamic-pituitary-adrenal axis, disrupting the normal hormonal signaling of reproductive cycling and resulting in MD. However, studies have also demonstrated similar EI in athletes, but with different menstrual function. Traditionally, energy balance has been evaluated in 24-hour time periods. Recent research suggests there is benefit to analyzing energy balance at smaller intervals to better address physiologic response in real time. It is possible that women who meet their daily EI needs could still, therefore, experience MD if the majority of the day is spent in energy deficit. Objective: The purpose of this study is to determine whether within-day energy balance is a factor in menstrual status in active adult females. Methods: Twenty active females tracked hourly EI and energy expenditure over three days. A two-page survey was utilized to obtain information on training, health, and menstrual status. Participants were also asked to respond to several questions regarding eating habits and attitude towards food. Within-day energy balance was calculated and evaluated using NutriTimingTM software. Collected energy balance data were analyzed for associations with menstrual status. Results: Participants spent more hours in a catabolic state (energy balance less than zero) than in an anabolic state (20.5 hrs vs 3.5 hrs) and averaged a caloric deficit of -504 kcal over 24-hours. Nine subjects (45%) had experienced loss of menses for greater than 3 months (LoM>3mos), indicative of amenorrhea. Hours spent in energy surplus >400 kcal was inversely correlated with LoM>3mos (r = -0.463; P = 0.04). The impact of number of miles run per week and menstrual dysfunction, based on a quartile stratification of miles run, were analyzed using an ANOVA with Tamhane non-parametric post hoc test. Significant differences were found between the upper two quartiles of distance run per week and LoM>3mos (P = 0.048). There was no relationship between end-of-day energy balance and Lom>3mos. Conclusion: Researchers and healthcare professionals would do well to examine energy balance in an hour-by-hour manner as it is has implications for MD. This would help to clarify whether within-day energy balance is a factor in MD, and allow for the development of appropriate intervention strategies to improve health and athletic outcomes for active women.