WorldWideScience

Sample records for net energy balances

  1. Net Balanced Floorplanning Based on Elastic Energy Model

    DEFF Research Database (Denmark)

    Liu, Wei; Nannarelli, Alberto

    2008-01-01

    with balanced net delays to increase the safety margins of the design. In this paper, we investigate the properties of floorplanning based on the elastic energy model. The B*-tree, which is based on an ordered binary tree, is used for circuit representation and the elastic energy is used as the cost function...

  2. Energy balance framework for Net Zero Energy buildings

    Science.gov (United States)

    Approaching a Net Zero Energy (NZE) building goal based on current definitions is flawed for two principal reasons - they only deal with energy quantities required for operations, and they do not establish a threshold, which ensures that buildings are optimized for reduced consum...

  3. Comparative analysis of net energy balance for satellite power systems (SPS) and other energy systems

    Energy Technology Data Exchange (ETDEWEB)

    Cirillo, R.R.; Cho, B.S.; Monarch, M.R.; Levine, E.P.

    1980-04-01

    The net energy balance of seven electric energy systems is assessed: two coal-based, one nuclear, two terrestrial solar, and two solar power satellites, with principal emphasis on the latter two systems. Solar energy systems require much less operating energy per unit of electrical output. However, on the basis of the analysis used here, coal and nuclear systems are two to five times more efficient at extracting useful energy from the primary resource base than are the solar energy systems. The payback period for all systems is less than 1.5 years, except for the terrestrial photovoltaic (19.8 yr) and the solar power satellite system (6.4 yr), both of which rely on energy-intensive silicon cells.

  4. Energy balance of maize production in Brazil: the energetic constraints of a net positive outcome

    Energy Technology Data Exchange (ETDEWEB)

    Soares, Luis Henrique de Barros; Alves, Bruno Jose Rodrigues; Urquiaga, Segundo

    2008-07-01

    Among the factors used to analyze and to establish the sustainability of a whole agricultural production system, the energy balance is one of the most powerful and robust. The maize production in Brazil is surely the reflex of an energy intensive system that demands many field operations and heavy fertilizer applications, notably nitrogen in urea form. This work presents an energy balance of this major crop adjusted to the Brazilian conditions of cultivation. The input components were grouped based on their energy contents, and the possible improvements in the agricultural practices that could improve energy balance and net energy withdrawn from the farming were considered. The replacement of N synthetic fertilizer by biological nitrogen fixation, whether the process is directly carried out by endophytic diazotroph bacteria or by means of a N{sub 2}- fixing legume culture planted before the main crop as a green-manure is also discussed. (author)

  5. Improvement potential for net energy balance of biodiesel derived from palm oil: A case study from Indonesian practice

    Energy Technology Data Exchange (ETDEWEB)

    Kamahara, Hirotsugu [Research Institute of Science for Safety and Sustainability, National Institute of Advanced Industrial Science and Technology, Tsukuba, Ibaraki 305-8569 (Japan); Hasanudin, Udin [Department of Agroindustrial Technology, University of Lampung, Bandar Lampung, Lampung 35145 (Indonesia); Widiyanto, Anugerah [International Cooperation Center for Engineering Education Development, Toyohashi University of Technology, Toyohashi, Aichi 441-8580 (Japan); Tachibana, Ryuichi [Department of Civil and Environmental Engineering, Nagaoka University of Technology, Nagaoka, Niigata 940-2188 (Japan); Atsuta, Yoichi; Goto, Naohiro; Daimon, Hiroyuki [Department of Environmental and Life Sciences, Toyohashi University of Technology, 1-1 Hibarigaoka, Tempaku, Toyohashi, Aichi 441-8580 (Japan); Fujie, Koichi [Graduate School of Environment and Information Sciences, Yokohama National University, Yokohama, Kanagawa 240-8501 (Japan)

    2010-12-15

    Biodiesel derived from palm oil has been recognized as a high-productivity oil crop among the first generation of biofuels. This study evaluated and discussed the net energy balance for biodiesel in Indonesia by calculating the net energy ratio (NER) and net energy production (NEP) form the total energy input and output. The results of the calculation of energy input for the default scenario demonstrated that the primary energy inputs in the biodiesel production lifecycle were the methanol feedstock, energy input during the biodiesel production process, and urea production. These three items amounted to 85% of the total energy input. Next, we considered and evaluated ways to potentially improve the energy balance by utilizing by-products and biogas from wastewater treatment in the palm oil mill. This result emphasized the importance of utilizing the biomass residue and by-products. Finally, we discussed the need to be aware of energy balance issues between countries when biofuels are transported internationally. (author)

  6. Net Zero Energy Buildings

    DEFF Research Database (Denmark)

    Marszal, Anna Joanna; Bourrelle, Julien S.; Musall, Eike

    2010-01-01

    and identify possible renewable energy supply options which may be considered in calculations. Finally, the gap between the methodology proposed by each organisation and their respective national building code is assessed; providing an overview of the possible changes building codes will need to undergo......The international cooperation project IEA SHC Task 40 / ECBCS Annex 52 “Towards Net Zero Energy Solar Buildings”, attempts to develop a common understanding and to set up the basis for an international definition framework of Net Zero Energy Buildings (Net ZEBs). The understanding of such buildings...... parameters used in the calculations are discussed and the various renewable supply options considered in the methodologies are summarised graphically. Thus, the paper helps to understand different existing approaches to calculate energy balance in Net ZEBs, highlights the importance of variables selection...

  7. Net radiation, sensible and latent heat flux densities on slopes computed by the energy balance method

    Science.gov (United States)

    Fritschen, Leo; Qian, Ping

    1990-01-01

    Energy balance components obtained over five grass-covered sloping surfaces near Manhattan, KS, using the Bowen ratio energy balance technique with the instruments mounted horizontally were compared with calculated values when the instruments were mounted parallel to the surfaces. Hourly values of the components changed when the instruments were parallel to the surfaces. The changes were larger at low solar angles (spring and fall) and on steeper slopes. An area average of daylight totals, assuming that all aspects were equally represented, changed only 0.1 percent on June 6 and 2.3 percent on October 11. The calculations, extended to steeper slopes, indicated small changes in the daylight totals for slopes of less than 10 deg.

  8. Energy balance of the global photovoltaic (PV) industry--is the PV industry a net electricity producer?

    Science.gov (United States)

    Dale, Michael; Benson, Sally M

    2013-04-02

    A combination of declining costs and policy measures motivated by greenhouse gas (GHG) emissions reduction and energy security have driven rapid growth in the global installed capacity of solar photovoltaics (PV). This paper develops a number of unique data sets, namely the following: calculation of distribution of global capacity factor for PV deployment; meta-analysis of energy consumption in PV system manufacture and deployment; and documentation of reduction in energetic costs of PV system production. These data are used as input into a new net energy analysis of the global PV industry, as opposed to device level analysis. In addition, the paper introduces a new concept: a model tracking energetic costs of manufacturing and installing PV systems, including balance of system (BOS) components. The model is used to forecast electrical energy requirements to scale up the PV industry and determine the electricity balance of the global PV industry to 2020. Results suggest that the industry was a net consumer of electricity as recently as 2010. However, there is a >50% that in 2012 the PV industry is a net electricity provider and will "pay back" the electrical energy required for its early growth before 2020. Further reducing energetic costs of PV deployment will enable more rapid growth of the PV industry. There is also great potential to increase the capacity factor of PV deployment. These conclusions have a number of implications for R&D and deployment, including the following: monitoring of the energy embodied within PV systems; designing more efficient and durable systems; and deploying PV systems in locations that will achieve high capacity factors.

  9. Understanding Net Zero Energy Buildings

    DEFF Research Database (Denmark)

    Salom, Jaume; Widén, Joakim; Candanedo, José

    2011-01-01

    Although several alternative definitions exist, a Net-Zero Energy Building (Net ZEB) can be succinctly described as a grid-connected building that generates as much energy as it uses over a year. The “net-zero” balance is attained by applying energy conservation and efficiency measures...... and by incorporating renewable energy systems. While based on annual balances, a complete description of a Net ZEB requires examining the system at smaller time-scales. This assessment should address: (a) the relationship between power generation and building loads and (b) the resulting interaction with the power grid....... This paper presents and categorizes quantitative indicators suitable to describe both aspects of the building’s performance. These indicators, named LMGI - Load Matching and Grid Interaction indicators, are easily quantifiable and could complement the output variables of existing building simulation tools...

  10. NASA Net Zero Energy Buildings Roadmap

    Energy Technology Data Exchange (ETDEWEB)

    Pless, S.; Scheib, J.; Torcellini, P.; Hendron, B.; Slovensky, M.

    2014-10-01

    In preparation for the time-phased net zero energy requirement for new federal buildings starting in 2020, set forth in Executive Order 13514, NASA requested that the National Renewable Energy Laboratory (NREL) to develop a roadmap for NASA's compliance. NASA detailed a Statement of Work that requested information on strategic, organizational, and tactical aspects of net zero energy buildings. In response, this document presents a high-level approach to net zero energy planning, design, construction, and operations, based on NREL's first-hand experience procuring net zero energy construction, and based on NREL and other industry research on net zero energy feasibility. The strategic approach to net zero energy starts with an interpretation of the executive order language relating to net zero energy. Specifically, this roadmap defines a net zero energy acquisition process as one that sets an aggressive energy use intensity goal for the building in project planning, meets the reduced demand goal through energy efficiency strategies and technologies, then adds renewable energy in a prioritized manner, using building-associated, emission- free sources first, to offset the annual energy use required at the building; the net zero energy process extends through the life of the building, requiring a balance of energy use and production in each calendar year.

  11. Energy Balance and Obesity

    Science.gov (United States)

    Hill, James O.; Wyatt, Holly R.; Peters, John C.

    2012-01-01

    This paper describes the interplay among energy intake, energy expenditure and body energy stores and illustrates how an understanding of energy balance can help develop strategies to reduce obesity. First, reducing obesity will require modifying both energy intake and energy expenditure and not simply focusing on either alone. Food restriction alone will not be effective in reducing obesity if human physiology is biased toward achieving energy balance at a high energy flux (i.e. at a high level of energy intake and expenditure). In previous environments a high energy flux was achieved with a high level of physical activity but in today's sedentary environment it is increasingly achieved through weight gain. Matching energy intake to a high level of energy expenditure will likely be more a more feasible strategy for most people to maintain a healthy weight than restricting food intake to meet a low level of energy expenditure. Second, from an energy balance point of view we are likely to be more successful in preventing excessive weight gain than in treating obesity. This is because the energy balance system shows much stronger opposition to weight loss than to weight gain. While large behavior changes are needed to produce and maintain reductions in body weight, small behavior changes may be sufficient to prevent excessive weight gain. In conclusion, the concept of energy balance combined with an understanding of how the body achieves balance may be a useful framework in helping develop strategies to reduce obesity rates. PMID:22753534

  12. Energy balance measurement

    DEFF Research Database (Denmark)

    Dhurandhar, N V; Schoeller, D; Brown, A W

    2015-01-01

    -reports of EI and PAEE are imperfect, but nevertheless deserving of use, to a view commensurate with the evidence that self-reports of EI and PAEE are so poor that they are wholly unacceptable for scientific research on EI and PAEE. While new strategies for objectively determining energy balance......Energy intake (EI) and physical activity energy expenditure (PAEE) are key modifiable determinants of energy balance, traditionally assessed by self-report despite its repeated demonstration of considerable inaccuracies. We argue here that it is time to move from the common view that self...... of energy balance....

  13. Investigations of a Cost-Optimal Zero Energy Balance

    DEFF Research Database (Denmark)

    Marszal, Anna Joanna; Nørgaard, Jesper; Heiselberg, Per

    2012-01-01

    The Net Zero Energy Building (Net ZEB) concept is worldwide recognised as a promising solution for decreasing buildings’ energy use. Nevertheless, a consistent definition of the Net ZEB concept is constantly under discussion. One of the points on the Net ZEB agenda is the zero energy balance...

  14. Load Matching and Grid Interaction of Net Zero Energy Buildings

    DEFF Research Database (Denmark)

    Voss, Karsten; Sartori, Igor; Napolitano, Assunta

    2010-01-01

    of seasonal energy storage on-site. Even though the wording “Net Zero Energy Building” focuses on the annual energy balance, large differences may occur between solution sets in the amount of grid interaction needed to reach the goal. The paper reports on the analysis of example buildings concerning the load...... matching and grid interaction. Indices to describe both issues are proposed and foreseen as part of a harmonized definition framework. The work is part of subtask A of the IEA SHCP Task40/ECBCS Annex 52: “Towards Net Zero Energy Solar Buildings”.......“Net Zero Energy Building” has become a prominent wording to describe the synergy of energy efficient building and renewable energy utilization to reach a balanced energy budget over a yearly cycle. Taking into account the energy exchange with a grid infrastructure overcomes the limitations...

  15. Energy balance in JET

    Directory of Open Access Journals (Sweden)

    G.F. Matthews

    2017-08-01

    Full Text Available In this paper we discuss results from the study of the energy balance in JET based on calculated heating energies, radiated energy from bolometry and tile calorimetry. Recent data enables us to be more confident in the numbers used and to exclude certain possibilities but the overall energy imbalance which typically amounts to 25% of total input remains unexplained. This shows that caution is required in interpreting fractional radiated powers which are commonly used to measure the effectiveness of impurity seeded scenarios at reducing divertor heat load.

  16. Appetite and energy balancing.

    Science.gov (United States)

    Rogers, Peter J; Brunstrom, Jeffrey M

    2016-10-01

    pleasure of eating it. The latter, which is similar to food reward, is determined primarily by the state of emptiness of the gut and food liking related to the food's sensory qualities and macronutrient value and the individual's dietary history. Importantly, energy density adds value because energy dense foods are less satiating kJ for kJ and satiation limits further intake. That is, energy dense foods promote energy intake by virtue (1) of being more attractive and (2) having low satiating capacity kJ for kJ, and (1) is partly a consequence of (2). Energy storage is adapted to feast and famine and that includes unevenness over time of the costs of obtaining and ingesting food compared with engaging in other activities. However, in very low-cost food environments with energy dense foods readily available, risk of obesity is high. This risk can be and is mitigated by dietary restraint, which in its simplest form could mean missing the occasional meal. Another strategy we discuss is the energy dilution achieved by replacing some sugar in the diet with low-calorie sweeteners. Perhaps as or more significant, though, is that belief in short-term energy balancing (the energy depletion model) may undermine attempts to eat less. Therefore, correcting narratives of eating to be consistent with biological reality could also assist with weight control. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  17. Calculation Tool for Determining the Net Energy Gain

    DEFF Research Database (Denmark)

    Laustsen, Jacob Birck; Svendsen, Svend

    2002-01-01

    for windows are presented. Based on these methods a program has been developed that determines the heat loss coefficient, U, and the total solar energy transmittance, g, for windows compounded of specific window components selected from a database. The program calculates the net energy gain for specific....... A proper and direct way to describe the energy performance of windows is by the net energy gain, E, which expresses the energy balance for the window. It is defined as the solar heat gain transmitted in minus the heat loss transmitted out through the window during the heating season. The net energy gain...... is dependent on both the U-values and the g-values. Beyond this it is dependent on the orientation of the windows and the climate and the actual period. This makes it difficult to choose the glazings and windows that are optimal with regard to energy performance in a given case. These facts have aroused a need...

  18. Defining net zero energy buildings

    CSIR Research Space (South Africa)

    Jonker Klunne, W

    2013-01-01

    Full Text Available Worldwide increasing attention to energy consumption and associated environmental impacts thereof has resulted in a critical attitude towards energy usage of building. Increasing costs of energy and dependence on energy service providers add...

  19. 47 CFR 69.608 - Carrier Common Line hypothetical net balance.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 3 2010-10-01 2010-10-01 false Carrier Common Line hypothetical net balance... SERVICES (CONTINUED) ACCESS CHARGES Exchange Carrier Association § 69.608 Carrier Common Line hypothetical net balance. The hypothetical net balance shall be equal to a Carrier Common Line revenue requirement...

  20. Energy performance of windows based on the net energy gain

    DEFF Research Database (Denmark)

    Svendsen, Svend; Kragh, Jesper; Laustsen, Jacob Birck

    2005-01-01

    The paper presents a new method to set up energy performance requirements and energy classes for windows of all dimensions and configurations. The net energy gain of windows is the solar gain minus the heat loss integrated over the heating season. The net energy gain can be calculated for one...... orientation or averaged over different orientations. The averaged value may be used for energy labeling of windows of standard size. Requirements in building codes may also be based on the net energy gain instead of the thermal transmittance of the window. The size and the configuration of the window, i.......e. number of glazing units, have a very large effect on the net energy gain. Therefore the energy labeling or the requirements based on the standard size may not give valid information on the energy performance of windows of non-standard size. The paper presents a method to set up requirements and classes...

  1. Net-Zero Energy Buildings: A Classification System Based on Renewable Energy Supply Options

    Energy Technology Data Exchange (ETDEWEB)

    Pless, S.; Torcellini, P.

    2010-06-01

    A net-zero energy building (NZEB) is a residential or commercial building with greatly reduced energy needs. In such a building, efficiency gains have been made such that the balance of energy needs can be supplied with renewable energy technologies. Past work has developed a common NZEB definition system, consisting of four well-documented definitions, to improve the understanding of what net-zero energy means. For this paper, we created a classification system for NZEBs based on the renewable sources a building uses.

  2. Net energy evaluation of feeds and determination of net energy requirements for pigs

    Directory of Open Access Journals (Sweden)

    Jean Noblet

    2007-07-01

    Full Text Available Feeds for pigs can be attributed different energy values according to, first, the step considered in energy utilization (DE: digestible energy, ME: metabolizable energy and NE: net energy and, second, the method used for estimation at each step. Reference methods for evaluating DE content are based on in vivo digestibility measurements; indirect estimates of DE values are obtained from in vitro methods or prediction equations based on chemical characteristics. Methods have also been proposed for estimating urinary energy (and gas energy to a smaller extent in order to calculate ME content from DE value. The NE values originate from energy balance studies (slaughter methods or, more commonly, indirect calorimetry measurements in respiration chambers and their compilation allows the calculation of NE prediction equations based on digestible nutrient contents or DE or ME contents. Such equations are applicable to both ingredients and compound feeds. They may differ between origins according to the fractionation method of organic matter or assumptions such as the NE requirement for maintenance (or fasting heat production. These measurements represent the bases for establishment of energy values in feeding tables. Results indicate that energy digestibility of feeds is negatively affected by dietary fibre content but this negative effect is attenuated with body weight increase, which suggests that feeds should be attributed DE values according to pig BW; in practice, at least two different DE values, one for growing-finishing pigs and one for mature pigs (reproductive sows, are recommended. The energy digestibility of pig feeds can also be affected by feed processing (pelletting, extrusion, etc.. Efficiency of ME utilization for NE averages 74-75% for conventional pig diets but it is directly dependent on diet chemical composition with efficiencies higher for ME from fat (90% or starch (82% than from protein or dietary fibre (60%. The hierarchy

  3. Dairy Proteins and Energy Balance

    DEFF Research Database (Denmark)

    Bendtsen, Line Quist

    High protein diets affect energy balance beneficially through decreased hunger, enhanced satiety and increased energy expenditure. Dairy products are a major source of protein. Dairy proteins are comprised of two classes, casein (80%) and whey proteins (20%), which are both of high quality......, but casein is absorbed slowly and whey is absorbed rapidly. The present PhD study investigated the effects of total dairy proteins, whey, and casein, on energy balance and the mechanisms behind any differences in the effects of the specific proteins. The results do not support the hypothesis that dairy...... proteins, whey or casein are more beneficial than other protein sources in the regulation of energy balance, and suggest that dairy proteins, whey or casein seem to play only a minor role, if any, in the prevention and treatment of obesity....

  4. Surface Energy Balance System (SEBS) Handbook

    Energy Technology Data Exchange (ETDEWEB)

    Cook, D. R. [Argonne National Lab. (ANL), Argonne, IL (United States)

    2016-01-01

    A Surface Energy Balance System (SEBS) has been installed collocated with each deployed Eddy Correlation Flux Measurement System (ECOR) at the Atmospheric Radiation Measurement (ARM) Climate Research Facility’s Southern Great Plains (SGP) site, North Slope of Alaska (NSA) site, first ARM Mobile Facility (AMF1), second ARM Mobile Facility (AMF2), and third ARM Mobile Facility (AMF3) at Oliktok Point (OLI). A SEBS was also deployed with the Tropical Western Pacific (TWP) site, before it was decommissioned. Data from these sites, including the retired TWP, are available in the ARM Data Archive. The SEBS consists of upwelling and downwelling solar and infrared radiometers within one net radiometer, a wetness sensor, and soil measurements. The SEBS measurements allow the comparison of ECOR sensible and latent heat fluxes with the energy balance determined from the SEBS and provide information on wetting of the sensors for data quality purposes.

  5. Energy Balance Bowen Ratio (EBBR) Handbook

    Energy Technology Data Exchange (ETDEWEB)

    Cook, D. R. [Argonne National Lab. (ANL), Argonne, IL (United States)

    2016-01-01

    The Energy Balance Bowen Ratio (EBBR) system produces 30-minute estimates of the vertical fluxes of sensible and latent heat at the local surface. Flux estimates are calculated from observations of net radiation, soil surface heat flux, and the vertical gradients of temperature and relative humidity (RH). Meteorological data collected by the EBBR are used to calculate bulk aerodynamic fluxes, which are used in the Bulk Aerodynamic Technique (BA) EBBR value-added product (VAP) to replace sunrise and sunset spikes in the flux data. A unique aspect of the system is the automatic exchange mechanism (AEM), which helps to reduce errors from instrument offset drift.

  6. Energy Balance Bowen Ratio Station (EBBR) Handbook

    Energy Technology Data Exchange (ETDEWEB)

    Cook, DR

    2011-02-23

    The energy balance Bowen ratio (EBBR) system produces 30-minute estimates of the vertical fluxes of sensible and latent heat at the local surface. Flux estimates are calculated from observations of net radiation, soil surface heat flux, and the vertical gradients of temperature and relative humidity (RH). Meteorological data collected by the EBBR are used to calculate bulk aerodynamic fluxes, which are used in the Bulk Aerodynamic Technique (BA) EBBR value-added product (VAP) to replace sunrise and sunset spikes in the flux data. A unique aspect of the system is the automatic exchange mechanism (AEM), which helps to reduce errors from instrument offset drift.

  7. Balancing energy flexibilities through aggregation

    DEFF Research Database (Denmark)

    Valsomatzis, Emmanouil; Hose, Katja; Pedersen, Torben Bach

    2014-01-01

    in both energy production and consumption, is the key to solving these problems. Flexibilities can be expressed as flex-offers, which due to their high number need to be aggregated to reduce the complexity of energy scheduling. In this paper, we discuss balance aggregation techniques that already during......One of the main goals of recent developments in the Smart Grid area is to increase the use of renewable energy sources. These sources are characterized by energy fluctuations that might lead to energy imbalances and congestions in the electricity grid. Exploiting inherent flexibilities, which exist...

  8. Windows with an improved energy balance of 30%

    DEFF Research Database (Denmark)

    Schultz, Jørgen Munthe

    carried out in the project. The large glass distance helps to reduce the traditional thermal bridge effect of the spacer and the integrated frame leads to an increase in transmitted solar energy. Furthermore, a controlled air exchange in case of pressure differences between the enclosures in the glazing......The aim of the project has been to investigate and to develop thermally improved windows based on an evaluation of the energy balance of the window, i.e. the total influence of the window on the energy consumption for space heating. The energy balance is the net heat flow per window area which...... been developed, which combines the results from several different building types and building orientations. The energy balance of the reference window has been calculated to -50 kWh/m2 window area, i.e. the refence window accounts for a net energy consumption for space heating of 50 kWh/m2 window area...

  9. Energy balance in coronal funnels

    Science.gov (United States)

    Rabin, Douglas

    1991-01-01

    The energy balance in magnetic flux tubes is examined semianalytically for the case in which thermal conduction balances radiation or in which enthalpy transport occurs. Different values are considered for areal constriction, shape, length, and maximum temperature. The overall energy budget of the solar corona is not significantly affected by magnetic constriction. A bowl-shaped funnel with a constriction factor of 4 describes the empirical differential-emission measure for log-T values between approximately 5.3 and 6.0. Loop-scaling relationships are derived for the full range of models to illustrate the dependence of the constant of proportionality on the properties of the magnetic constriction. Constriction can reduce the total energy requirement of the funnel by a factor of 5 and not affect the differential emission in flow-dominated models.

  10. Net-Zero-Energy Model for Sustainable Wastewater Treatment.

    Science.gov (United States)

    Yan, Peng; Qin, Rong-Cong; Guo, Jin-Song; Yu, Qiang; Li, Zhe; Chen, You-Peng; Shen, Yu; Fang, Fang

    2017-01-17

    A large external energy input prevents wastewater treatment from being environmentally sustainable. A net-zero-energy (NZE) wastewater treatment concept based on biomass energy recycling was proposed to avoid wasting resources and to promote energy recycling in wastewater treatment plants (WWTPs). Simultaneously, a theoretical model and boundary condition based on energy balance were established to evaluate the feasibility of achieving NZE in WWTPs; the model and condition were employed to analyze data from 20 conventional WWTPs in China. A total of six WWTPs can currently export excess energy, eight WWTPs can achieve 100% energy self-sufficiency by adjusting the metabolic material allocation, and six municipal WWTPs cannot achieve net-zero energy consumption based on the evaluation of the theoretical model. The NZE model offset 79.5% of the electricity and sludge disposal cost compared with conventional wastewater treatment. The NZE model provides a theoretical basis for the optimization of material regulation for the effective utilization of organic energy from wastewater and promotes engineering applications of the NZE concept in WWTPs.

  11. Importance of energy balance in agriculture.

    Science.gov (United States)

    Meco, R.; Moreno, M. M.; Lacasta, C.; Tarquis, A. M.; Moreno, C.

    2012-04-01

    inputs) ones. Energy outputs (EO) are considered as the calorific value of the harvested biomass (main products and sub-products), calculated from the total production (kg/ha) and its corresponding energy coefficient (strongly correlated to the biochemical composition of the products). Based on energy inputs and outputs, energy efficiency can be expressed as (i) net energy produced (NE) (also known as energy gain or energy balance, calculated as EI-EO and expressed as MJ/ha), (ii) the energy output/input ratio (also known as energy efficiency and calculated as EO/EI), and (iii) energy productivity (EP) (Crop yield/EI, expressed as kg/MJ). Funding provided by Spanish Ministerio de Ciencia e Innovación (MICINN) through project no. AGL2010-21501/AGR is greatly appreciated.

  12. Net-Zero Energy Technical Shelter

    DEFF Research Database (Denmark)

    Zhang, Chen; Heiselberg, Per; Jensen, Rasmus Lund

    2014-01-01

    Technical shelters are the basic structures for storing electronic and technical equipment, and commonly used for telecommunication base station, windmill, gas station, etc. Due to their high internal heat load density and special operation schedule, they consume more energy than normal residential...... or commercial buildings. On the other hand, it is a big challenge to power the technical shelter in remote area where the grids are either not available or the expansion of grid is expensive. In order to minimize the energy consumption and obtain a reliable and cost-efficient power solution for technical...... shelter, this study will apply the net-zero energy concept into the technical shelter design. The energy conservation can be achieved by proper design of building envelop and optimization of the cooling strategies. Both experiments and numerical simulations are carried out to investigate the indoor...

  13. A Conversation on Zero Net Energy Buildings

    Energy Technology Data Exchange (ETDEWEB)

    Eley, Charles; Gupta, Smita; Torcellini, Paul; Mchugh, Jon; Liu, Bing; Higgins, Cathy; Iplikci, Jessica; Rosenberg, Michael I.

    2017-06-30

    The submitted Roundtable discussion covers zero net energy (ZNE) buildings and their expansion into the market as a more widely adopted approach for various building types and sizes. However, the market is still small, and this discussion brings together distinguished researchers, designers, policy makers, and program administrations to represent the key factors making ZNE building more widespread and mainstream from a broad perspective, including governments, utilities, energy-efficiency research institutes, and building owners. This roundtable was conducted by the ASHRAE Journal with Bing Liu, P.E., Member ASHRAE, Charles Eley, FAIA, P.E., Member ASHRAE; Smita Gupta, Itron; Cathy Higgins, New Buildings Institute; Jessica Iplikci, Energy Trust of Oregon; Jon McHugh, P.E., Member ASHRAE; Michael Rosenberg, Member ASHRAE; and Paul Torcellini, Ph.D., P.E., NREL.

  14. 47 CFR 69.609 - End User Common Line hypothetical net balances.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 3 2010-10-01 2010-10-01 false End User Common Line hypothetical net balances... SERVICES (CONTINUED) ACCESS CHARGES Exchange Carrier Association § 69.609 End User Common Line hypothetical net balances. (a) If the company does not participate in the association tariff for such element, the...

  15. The Sower's way. Quantifying the Narrowing Net-Energy Pathways to a Global Energy Transition

    CERN Document Server

    Sgouridis, Sgouris; Csala, Denes

    2016-01-01

    Planning the appropriate renewable energy installation rate should balance two partially contradictory objectives: substituting fossil fuels fast enough to stave-off the worst consequences of climate change while maintaining a sufficient net energy flow to support the world's economy. The upfront energy invested in constructing a renewable energy infrastructure subtracts from the net energy available for societal energy needs, a fact typically neglected in energy projections. Modeling feasible energy transition pathways to provide different net energy levels we find that they are critically dependent on the fossil fuel emissions cap and phase-out profile and on the characteristic energy return on energy invested of the renewable energy technologies. The easiest pathway requires installation of renewable energy plants to accelerate from 0.12TWp/year in 2013 to peak between 6.6 and 10.4 TWp/year, for an early or a late fossil-fuel phase-out respectively in order for emissions to stay within the recommended CO2 ...

  16. A Conversation on Zero Net Energy Buildings

    Energy Technology Data Exchange (ETDEWEB)

    Torcellini, Paul A [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Eley, Charles [Consultant; Gupta, Smita [Itron; McHugh, Jon [McHugh Energy Consultants; Lui, Bing [Pacific Northwest National Laboratory; Higgins, Cathy [New Buildings Institute; Iplikci, Jessica [Energy Trust of Oregon; Rosenberg, Michael [Pacific Northwest National Laboratory

    2017-06-01

    Recently, zero net energy (ZNE) buildings have moved from state-of-the-art small project demonstrations to a more widely adopted approach across the country among various building types and sizes. States such as California set policy goals of all new residential construction to be NZE by 2020 and all commercial buildings to be NZE by 2030. However, the market for designing, constructing, and operating ZNE buildings is still relatively small. We bring together distinguished experts to share their thoughts on making ZNE buildings more widespread and mainstream from a broad perspective, including governments, utilities, energy-efficiency research institutes, and building owners. This conversation also presents the benefits of ZNE and ways to achieve that goal in the design and operation of buildings. The following is a roundtable conducted by ASHRAE Journal and Bing Liu with Charles Eley, Smita Gupta, Cathy Higgins, Jessica Iplikci, Jon McHugh, Michael Rosenberg, and Paul Torcellini.

  17. Army Net Zero Prove Out. Net Zero Energy Best Practices

    Science.gov (United States)

    2014-11-18

    energy which is then used to drive a heat engine to generate electrical power. Geothermal Power – These systems use thermal energy generated and...stored in the earth as a generating source for electricity. Several pilot installations are investigating this technology by conducting geothermal ...concentrate solar thermal energy which is then used to drive a heat engine to generate electrical power. • Geothermal Power - These systems use thermal energy

  18. A Cellular Approach to Net-Zero Energy Cities

    Directory of Open Access Journals (Sweden)

    Miguel Amado

    2017-11-01

    Full Text Available Recent growth in the use of photovoltaic technology and a rapid reduction in its cost confirms the potential of solar power on a large scale. In this context, planning for the deployment of smart grids is among the most important challenges to support the increased penetration of solar energy in urban areas and to ensure the resilience of the electricity system. As part this effort, the present paper describes a cellular approach to a Net-Zero energy concept, based on the balance between the potential solar energy supply and the existing consumption patterns at the urban unit scale. To do that, the Geographical Urban Units Delimitation model (GUUD has been developed and tested on a case study. By applying the GUUD model, which combines Geographic Information Systems (GIS, parametric modelling, and solar dynamic analysis, the whole area of the city was divided into urban cells, categorized as solar producers and energy consumers. The discussion around three theoretical scenarios permits us to explore how smart grids can be approached and promoted from an urban planning perspective. The paper provides insights into how urban planning can be a driver to optimize and manage energy balance across the city if the deployment of smart grids is correctly integrated in its operative process.

  19. Net Zero Energy Military Installations: A Guide to Assessment and Planning

    Energy Technology Data Exchange (ETDEWEB)

    Booth, S.; Barnett, J.; Burman, K.; Hambrick, J.; Westby, R.

    2010-08-01

    The U.S. Department of Defense (DoD) recognizes the strategic importance of energy to its mission, and is working to reduce energy consumption and enhance energy self-sufficiency by drawing on local clean energy sources. A joint initiative formed between DoD and the U.S. Department of Energy (DOE) in 2008 to address military energy use led to a task force to examine the potential for net zero energy military installations, which would produce as much energy on site as they consume in buildings, facilities, and fleet vehicles. This report presents an assessment and planning process to examine military installations for net zero energy potential. Net Zero Energy Installation Assessment (NZEIA) presents a systematic framework to analyze energy projects at installations while balancing other site priorities such as mission, cost, and security.

  20. Energy Balance in Huntington's Disease.

    Science.gov (United States)

    Gil Polo, Cecilia; Cubo Delgado, Esther; Mateos Cachorro, Ana; Rivadeneyra Posadas, Jéssica; Mariscal Pérez, Natividad; Armesto Formoso, Diana

    2015-01-01

    Little is known about the energy needs in Huntington's disease (HD). The aims of this study are to analyze and compare the total energy expenditure (TEE) and energy balance (EB) in a representative sample of HD patients with healthy controls. This is an observational, case-control single-center study. Food caloric energy intake (EI) and TEE were considered for estimating EB. A dietary recall questionnaire was used to assess the EI. TEE was computed as the sum of resting energy expenditure (REE), measured by indirect calorimetry and physical activity (PA) monitored by an actigraph. A total of 22 patients were included (36% men, mean age 50.3 ± 15.6 years, motor Unified Huntington's Disease Scale 27.9 ± 23.7, total functional capacity 11.0 (7.0-13.0), EI 38.6 ± 10.0 kcal/kg, PA 5.3 (3.0-7.4) kcal/kg, REE 30.9 ± 6.4 kcal/kg, TEE 2,023.4 (1,592.0-2,226.5) kcal/day) and 18 controls (50% men, mean age 47.4 ± 13.8 years, EI 38.6 ± 10.3 kcal/kg, PA 8.4 (5.0-13.8) kcal/kg, REE 30.8 ± 6.6 kcal/kg, TEE 2,281.0 (2,057.3-2,855.3) kcal/day). TEE was significantly lower in patients compared to controls (p = 0.03). PA was lower in patients compared to controls (p = 0.02). Although patients with HD appeared to have lower energy expenditure, mainly due to decreased voluntary PA, they were still able to maintain their energy needs with an adequate food intake. © 2015 S. Karger AG, Basel.

  1. Zero Net Energy Myths and Modes of Thought

    Energy Technology Data Exchange (ETDEWEB)

    Rajkovich, Nicholas B.; Diamond, Rick; Burke, Bill

    2010-09-20

    The U.S. Department of Energy (DOE), the California Public Utilities Commission (CPUC), and a number of professional organizations have established a target of zero net energy (ZNE) in buildings by 2030. One definition of ZNE is a building with greatly reduced needs for energy through efficiency gains with the balance of energy needs supplied by renewable technologies. The push to ZNE is a response to research indicating that atmospheric concentrations of greenhouse gases have increased sharply since the eighteenth century, resulting in a gradual warming of the Earth?s climate. A review of ZNE policies reveals that the organizations involved frame the ZNE issue in diverse ways, resulting in a wide variety of myths and a divergent set of epistemologies. With federal and state money poised to promote ZNE, it is timely to investigate how epistemologies, meaning a belief system by which we take facts and convert them into knowledge upon which to take action, and the propagation of myths might affect the outcome of a ZNE program. This paper outlines myths commonly discussed in the energy efficiency and renewable energy communities related to ZNE and describes how each myth is a different way of expressing"the truth." The paper continues by reviewing a number of epistemologies common to energy planning, and concludes that the organizations involved in ZNE should work together to create a"collaborative rationality" for ZNE. Through this collaborative framework it is argued that we may be able to achieve the ZNE and greenhouse gas mitigation targets.

  2. Energy performance of net-zero and near net-zero energy homes in New England

    Science.gov (United States)

    Thomas, Walter D.

    Net-Zero Energy Homes (NZEHs) are homes that consume no more energy than they produce on site during the course of a year. They are well insulated and sealed, use energy efficient appliances, lighting, and mechanical equipment, are designed to maximize the benefits from day lighting, and most often use a combination of solar hot water, passive solar and photovoltaic (PV) panels to produce their on-site energy. To date, NZEHs make up a miniscule percentage of homes in the United States, and of those, few have had their actual performance measured and analyzed once built and occupied. This research focused on 19 NZEHs and near net-zero energy homes (NNZEHs) built in New England. This set of homes had varying designs, numbers of occupants, and installed technologies for energy production, space heating and cooling, and domestic hot water systems. The author worked with participating homeowners to collect construction and systems specifications, occupancy information, and twelve months of energy consumption, production and cost measurements, in order to determine whether the homes reached their respective energy performance design goals. The author found that six out of ten NZEHs achieved net-zero energy or better, while all nine of the NNZEHs achieved an energy density (kWh/ft 2/person) at least half as low as the control house, also built in New England. The median construction cost for the 19 homes was 155/ft 2 vs. 110/ft2 for the US average, their average monthly energy cost was 84% below the average for homes in New England, and their estimated CO2 emissions averaged 90% below estimated CO2 emissions from the control house. Measured energy consumption averaged 14% below predictions for the NZEHs and 38% above predictions for the NNZEHs, while generated energy was within +/- 10% of predicted for 17 out of 18 on-site PV systems. Based on these results, the author concludes that these types of homes can meet or exceed their designed energy performance (depending on

  3. Estimates of Regional Equilibrium Line Altitudes and Net Mass Balance from MODIS Imagery

    Science.gov (United States)

    Shea, J. M.; Menounos, B.; Moore, R. D.

    2011-12-01

    Glacier mass balance is a key variable used to assess the health of glaciers and ice sheets. Estimates of glacier mass balance are required to model the dynamic response of glaciers and ice sheets to climate change, estimate sea-level contribution from surface melt, and document the response of glaciers to climate forcing. Annually resolved estimates of regional mass balance for mountain ranges is often inferred from a sparse network of ground-based measurements of mass balance for individual glaciers. Given that net mass balance is highly correlated with the annual equilibrium line altitude (ELA), we develop an automated approach to estimate the ELA, and by inference net mass balance, on large glaciers and icefields using MODIS 250 m imagery (MOD02QKM). We discriminate areas of bare ice and snow/firn using the product of MODIS' red (0.620 - 0.670 μ m) and near infrared (0.841 - 0.876 μ m) bands. To assess the skill in estimating glacier ELAs, we compare ELAs derived from (1) manual delineation and (2) unsupervised classification of the band product to ground-based observations of ELA and net mass balance at seven long term mass-balance monitoring sites in western North America (Gulkana, Wolverine, Lemon Creek, Taku, Place, Peyto, and South Cascade). Spatial and temporal variations in MODIS-derived ELAs provide an opportunity to validate regional mass-balance models, estimate surface melt contributions to sea-level rise, and examine the cryospheric response to climate change.

  4. Assessment of Global Annual Atmospheric Energy Balance from Satellite Observations

    Science.gov (United States)

    Lin, Bing; Stackhouse, Paul; Minnis, Patrick; Wielicki, Bruce A.; Hu, Yongxiang; Sun, Wenbo; Fan, Tai-Fang (Alice); Hinkelman, Laura

    2008-01-01

    Global atmospheric energy balance is one of the fundamental processes for the earth's climate system. This study uses currently available satellite data sets of radiative energy at the top of atmosphere (TOA) and surface and latent and sensible heat over oceans for the year 2000 to assess the global annual energy budget. Over land, surface radiation data are used to constrain assimilated results and to force the radiation, turbulent heat, and heat storage into balance due to a lack of observation-based turbulent heat flux estimations. Global annual means of the TOA net radiation obtained from both direct measurements and calculations are close to zero. The net radiative energy fluxes into the surface and the surface latent heat transported into the atmosphere are about 113 and 86 Watts per square meter, respectively. The estimated atmospheric and surface heat imbalances are about -8 9 Watts per square meter, values that are within the uncertainties of surface radiation and sea surface turbulent flux estimates and likely systematic biases in the analyzed observations. The potential significant additional absorption of solar radiation within the atmosphere suggested by previous studies does not appear to be required to balance the energy budget the spurious heat imbalances in the current data are much smaller (about half) than those obtained previously and debated at about a decade ago. Progress in surface radiation and oceanic turbulent heat flux estimations from satellite measurements significantly reduces the bias errors in the observed global energy budgets of the climate system.

  5. Physical activity, energy balance and obesity.

    OpenAIRE

    Jordi Salas-Salvado; Jose Luis Griera; Jose Maria Manzanares; Montserrat Barbany; Jose Contreras; Pilar Amigo

    2007-01-01

    Physical activity, energy balance and obesity. Obesity appears when energy intake exceeds energy expenditure. The most important variable compound of energy expenditure is physical activity. The global epidemics of obesity seem closely related to reduced physical activity and sedentariness widely increasing nowadays. Once obesity has developed, caloric intake becomes similar to energy expenditure. To lose weight, besides decreasing energy intake, energy expenditure must be increased. The p...

  6. Comprehensive Energy Balance Measurements in Mice.

    Science.gov (United States)

    Moir, Lee; Bentley, Liz; Cox, Roger D

    2016-09-01

    In mice with altered body composition, establishing whether it is food intake or energy expenditure, or both, that is the major determinant resulting in changed energy balance is important. In order to ascertain where the imbalance is, the acquisition of reproducible data is critical. Therefore, here we provide detailed descriptions of how to determine energy balance in mice. This encompasses protocols for establishing energy intake from home cage measurement of food intake, determining energy lost in feces using bomb calorimetry, and using equations to calculate parameters such as energy intake (EI), digested energy intake (DEI), and metabolisable energy intake (MEI) to determine overall energy balance. We also discuss considerations that should be taken into account when planning these experiments, including diet and sample sizes. © 2016 by John Wiley & Sons, Inc. Copyright © 2016 John Wiley & Sons, Inc.

  7. Fermentative biohydrogen production: Evaluation of net energy gain

    Energy Technology Data Exchange (ETDEWEB)

    Perera, Karnayakage Rasika J.; Ketheesan, Balachandran; Nirmalakhandan, Nagamany [Civil Engineering Department, New Mexico State University, Las Cruces, NM 88011 (United States); Gadhamshetty, Venkataramana [Civil and Environmental Engineering Dept., Rensselaer Polytechnic Institute, Troy, NY 12180 (United States)

    2010-11-15

    Most dark fermentation (DF) studies had resorted to above-ambient temperatures to maximize hydrogen yield, without due consideration of the net energy gain. In this study, literature data on fermentative hydrogen production from glucose, sucrose, and organic wastes were compiled to evaluate the benefit of higher fermentation temperatures in terms of net energy gain. This evaluation showed that the improvement in hydrogen yield at higher temperatures is not justified as the net energy gain not only declined with increase of temperature, but also was mostly negative when the fermentation temperature exceeded 25 C. To maximize the net energy gain of DF, the following two options for recovering additional energy from the end products and to determine the optimal fermentation temperature were evaluated: methane production via anaerobic digestion (AD); and direct electricity production via microbial fuel cells (MFC). Based on net energy gain, it is concluded that DF has to be operated at near-ambient temperatures for the net energy gain to be positive; and DF + MFC can result in higher net energy gain at any temperature than DF or DF + AD. (author)

  8. The effect of caffeine on energy balance.

    Science.gov (United States)

    Harpaz, Eynav; Tamir, Snait; Weinstein, Ayelet; Weinstein, Yitzhak

    2017-01-01

    The global prevalence of obesity has increased considerably in the last two decades. Obesity is caused by an imbalance between energy intake (EI) and energy expenditure (EE), and thus negative energy balance is required to bring about weight loss, which can be achieved by either decreasing EI or increasing EE. Caffeine has been found to influence the energy balance by increasing EE and decreasing EI, therefore, it can potentially be useful as a body weight regulator. Caffeine improves weight maintenance through thermogenesis, fat oxidation, and EI. The sympathetic nervous system is involved in the regulation of energy balance and lipolysis (breakdown of lipids to glycerol and free fatty acids) and the sympathetic innervation of white adipose tissue may play an important role in the regulation of total body fat. This article reviews the current knowledge on the thermogenic properties of caffeine, and its effects on appetite and EI in relation to energy balance and body weight regulation.

  9. Modelling the energy balance of an anaerobic digester fed with cattle manure and renewable energy crops.

    Science.gov (United States)

    Lübken, Manfred; Wichern, Marc; Schlattmann, Markus; Gronauer, Andreas; Horn, Harald

    2007-10-01

    Knowledge of the net energy production of anaerobic fermenters is important for reliable modelling of the efficiency of anaerobic digestion processes. By using the Anaerobic Digestion Model No. 1 (ADM1) the simulation of biogas production and composition is possible. This paper shows the application and modification of ADM1 to simulate energy production of the digestion of cattle manure and renewable energy crops. The paper additionally presents an energy balance model, which enables the dynamic calculation of the net energy production. The model was applied to a pilot-scale biogas reactor. It was found in a simulation study that a continuous feeding and splitting of the reactor feed into smaller heaps do not generally have a positive effect on the net energy yield. The simulation study showed that the ratio of co-substrate to liquid manure in the inflow determines the net energy production when the inflow load is split into smaller heaps. Mathematical equations are presented to calculate the increase of biogas and methane yield for the digestion of liquid manure and lipids for different feeding intervals. Calculations of different kinds of energy losses for the pilot-scale digester showed high dynamic variations, demonstrating the significance of using a dynamic energy balance model.

  10. Energy balance in solid state fermentation processes

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez, L.J.A.; Torres, A.; Echevarria, J.; Saura, G. (Instituto Cubano de Investigaciones de los Derivados de la Cana de Azucar (ICIDCA), La Habana (Cuba))

    1991-01-01

    It was applied a macroscopic energy balance to a solid state fermentation process and an electron balance in order to estimate the temperature and the heat evolved in the process. There were employed several equations that describe the development of the system and offer the possibility to design or control such fermentations. (orig.).

  11. Criteria for Definition of Net Zero Energy Buildings

    DEFF Research Database (Denmark)

    Sartori, Igor; Napolitano, Assunta; Marszal, Anna Joanna

    2010-01-01

    without a clear understanding and countries are enacting policies and national targets based on the concept without a clear definition in place. This paper presents a harmonised framework for describing the relevant characteristics of Net ZEBs in a series of criteria. Evaluation of the criteria......The idea of a Net Zero Energy Building (Net ZEB) is understood conceptually, as it is understood that the way a Net ZEB is defined affects significantly the way it is designed in order to achieve the goal. However, little agreement exists on a common definition; the term is used commercially...... and selection of the related options becomes a methodology for elaborating sound Net ZEB definitions in a formal, systematic and comprehensive way, creating the basis for legislations and action plans to effectively achieve the political targets. The common denominator for the different possible Net ZEB...

  12. Renewable Generation Effect on Net Regional Energy Interchange: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Diakov, Victor; Brinkman, Gregory; Denholm, Paul; Jenkin, Thomas; Margolis, Robert

    2015-07-30

    Using production-cost model (PLEXOS), we simulate the Western Interchange (WECC) at several levels of the yearly renewable energy (RE) generation, between 13% and 40% of the total load for the year. We look at the overall energy exchange between a region and the rest of the system (net interchange, NI), and find it useful to examine separately (i) (time-)variable and (ii) year-average components of the NI. Both contribute to inter-regional energy exchange, and are affected by wind and PV generation in the system. We find that net load variability (in relatively large portions of WECC) is the leading factor affecting the variable component of inter-regional energy exchange, and the effect is quantifiable: higher regional net load correlation with the rest of the WECC lowers net interchange variability. Further, as the power mix significantly varies between WECC regions, effects of ‘flexibility import’ (regions ‘borrow’ ramping capability) are also observed.

  13. Generating a positive energy balance from using rice straw for anaerobic digestion

    Directory of Open Access Journals (Sweden)

    V.H. Nguyen

    2016-11-01

    The net energy of the rice straw supply chain for biogas generation through AD is 3,500 MJ per ton of straw. This rice straw management option can provide a 70% net output energy benefit. The research highlighted the potential of rice straw as a clean fuel source with a positive energy balance, helping to reduce greenhouse gas emissions compared with the existing practice of burning it in the field.

  14. Energy balance of biodiesel production from canola

    OpenAIRE

    Silva,Luis Felipe Lima e; Gonçalves,Wilson Magela; Maluf,Wilson Roberto; Resende,Luciane Vilela; Sarmiento,Christiany Mattioli; Licursi,Vicente; Moretto,Paulo

    2017-01-01

    ABSTRACT: The aim of the present study was to estimate the energy balance (output/input ratio) of the canola crop for biodiesel production, under Brazilian conditions. Fossil energy expended in the production of 600kg of oil per hectare was 7,146,537kcal. The estimated energy yield per hectare was 9,930,000kcal from the production of 1,500kg ha-1 of seeds (40% oil and 60% oil cake), which resulted in an energy balance of 1.39. Results indicated the viability of biofuel production from canola,...

  15. [Energy balance among female athletes].

    Science.gov (United States)

    Arieli, Rakefet; Constantini, Naama

    2012-02-01

    Athletes need to consume sufficient energy to meet their training demands, maintain their health, and if young, to ensure their growth and development. Athletes are often preoccupied by their body weight and shape, and in some sports might be subjected to pressure to lose weight by coaches, peers or themselves. Eating disorders and poor eating habits are prevalent among female athletes, especially in sport disciplines where low body weight is required to improve performance or for "aesthetic" appearance or in weight category sports. Low energy intake has deleterious effects on many systems, including the cardiovascular system, several hormonal pathways, musculoskeletal system, fluids and electrolytes, thermoregulation, growth and development. Various fitness components and overall performance are also negatively affected. All these, together with poor nutritional status that causes vitamin and mineral deficiencies, poor concentration and depression, put the athlete at an increased injury risk. Energy availability is now recognized as the primary factor initiating these health problems. Energy availability is defined as dietary energy intake minus exercise energy expenditure. If below 30 kcal/kg fat free mass per day, reproductive system functions, as well as other metabolic systems, might be suppressed. The case presented is of a young female Judoka, who complained of fatigue and weakness. Medical and nutritional assessment revealed that she suffered from low energy availability, which slowed her growth and development, and negatively affected her health and athletic performance. This case study emphasizes the importance of adequate energy availability in young female athletes in order to ensure their health.

  16. Energy balance of biodiesel production from canola

    Directory of Open Access Journals (Sweden)

    Luis Felipe Lima e Silva

    Full Text Available ABSTRACT: The aim of the present study was to estimate the energy balance (output/input ratio of the canola crop for biodiesel production, under Brazilian conditions. Fossil energy expended in the production of 600kg of oil per hectare was 7,146,537kcal. The estimated energy yield per hectare was 9,930,000kcal from the production of 1,500kg ha-1 of seeds (40% oil and 60% oil cake, which resulted in an energy balance of 1.39. Results indicated the viability of biofuel production from canola, but also showed the need to improve the technology used to increase the energy and economic balance ratios.

  17. Energy Landscape of Social Balance

    Science.gov (United States)

    Marvel, Seth A.; Strogatz, Steven H.; Kleinberg, Jon M.

    2009-11-01

    We model a close-knit community of friends and enemies as a fully connected network with positive and negative signs on its edges. Theories from social psychology suggest that certain sign patterns are more stable than others. This notion of social “balance” allows us to define an energy landscape for such networks. Its structure is complex: numerical experiments reveal a landscape dimpled with local minima of widely varying energy levels. We derive rigorous bounds on the energies of these local minima and prove that they have a modular structure that can be used to classify them.

  18. Partitioning the net ecosystem carbon balance of a semiarid steppe into biological and geological components

    NARCIS (Netherlands)

    Rey, A.; Belelli Marchesini, L.; Etiope, G.; Papale, D.; Canfora, E.; Valentini, R.; Pegoraro, E.

    2014-01-01

    Recent studies have highlighted the need to consider geological carbon sources when estimating the net ecosystem carbon balance (NECB) of terrestrial ecosystems located in areas potentially affected by geofluid circulation. We propose a new methodology using physical parameters of the atmospheric

  19. Dissolved carbon leaching from soil is a crucial component of the net ecosystem carbon balance

    NARCIS (Netherlands)

    Kindler, R.; Siemens, J.; Kaiser, K.; Moors, E.J.

    2011-01-01

    Estimates of carbon leaching losses from different land use systems are few and their contribution to the net ecosystem carbon balance is uncertain. We investigated leaching of dissolved organic carbon (DOC), dissolved inorganic carbon (DIC), and dissolved methane (CH4), at forests, grasslands, and

  20. An energy balance perspective on regional CO2-induced temperature changes in CMIP5 models

    OpenAIRE

    Räisänen, Jouni

    2017-01-01

    An energy balance decomposition of temperature changes is conducted for idealized transient CO2-only simulations in the fifth phase of the Coupled Model Intercomparison Project. The multimodel global mean warming is dominated by enhanced clear-sky greenhouse effect due to increased CO2 and water vapour, but other components of the energy balance substantially modify the geographical and seasonal patterns of the change. Changes in the net surface energy flux are important over the oceans, bein...

  1. Dairy beverages and energy balance

    DEFF Research Database (Denmark)

    Astrup, Arne; Chaput, Jean-Philippe; Gilbert, Jo-Anne

    2010-01-01

    to exist. We have found that high versus low calcium intakes from dairy products had no effect on 24-h energy expenditure or substrate oxidation rates, but fecal fat excretion increased approximately 2.5-fold on the high-calcium diets. In a meta-analysis of intervention studies we found that increasing...... dairy calcium intake by 1200mg/day resulted in increased fecal fat excretion by 5.2 (1.6-8.8) g/day. Newer research shows that humans possess taste receptors for calcium in the gastrointestinal tract and that signaling may be linked to appetite regulation. A new line of evidence suggests...... that an inadequate calcium intake during an energy restricted weight loss program may trigger hunger and impair compliance to the diet. These mechanisms may be part of the explanation for the protective effects of dairy products with regard to obesity and metabolic syndrome....

  2. Net energy analysis: Powerful tool for selecting electric power options

    Science.gov (United States)

    Baron, S.

    A number of net energy analysis studies have been conducted in recent years for electric power production from coal, oil and uranium fuels; synthetic fuels from coal and oil shale; and heat and electric power from solar energy. This technique is an excellent indicator of investment costs, environmental impact and potential economic competitiveness of alternative electric power systems for energy planners from the Eastern European countries considering future options. Energy conservation is also important to energy planners and the net energy analysis technique is an excellent accounting system on the extent of energy resource conservation. The author proposes to discuss the technique and to present the results of his studies and others in the field. The information supplied to the attendees will serve as a powerful tool to the energy planners considering their electric power options in the future.

  3. Net energy analysis - powerful tool for selecting elective power options

    Energy Technology Data Exchange (ETDEWEB)

    Baron, S. [Brookhaven National Laboratory, Upton, NY (United States)

    1995-12-01

    A number of net energy analysis studies have been conducted in recent years for electric power production from coal, oil and uranium fuels; synthetic fuels from coal and oil shale; and heat and electric power from solar energy. This technique is an excellent indicator of investment costs, environmental impact and potential economic competitiveness of alternative electric power systems for energy planners from the Eastern European countries considering future options. Energy conservation is also important to energy planners and the net energy analysis technique is an excellent accounting system on the extent of energy resource conservation. The author proposes to discuss the technique and to present the results of his studies and others in the field. The information supplied to the attendees will serve as a powerful tool to the energy planners considering their electric power options in the future.

  4. Historic simulation of net ecosystem carbon balance for the Great Dismal Swamp

    Science.gov (United States)

    Sleeter, Rachel

    2017-01-01

    Estimating ecosystem carbon (C) balance relative to natural disturbances and land management strengthens our understanding of the benefits and tradeoffs of carbon sequestration. We conducted a historic model simulation of net ecosystem C balance in the Great Dismal Swamp, VA. for the 30-year time period of 1985-2015. The historic simulation of annual carbon flux was calculated with the Land Use and Carbon Scenario Simulator (LUCAS) model. The LUCAS model utilizes a state-and-transition simulation model coupled with a carbon stock-flow accounting model to estimate net ecosystem C balance, and long term sequestration rates under various ecological conditions and management strategies. The historic model simulation uses age-structured forest growth curves for four forest species, C stock and flow rates for 8 pools and 14 fluxes, and known data for disturbance and management. The annualized results of C biomass are provided in this data release in the following categories: Growth, Heterotrophic Respiration (Rh), Net Ecosystem Production (NEP), Net Biome Production (NBP), Below-ground Biomass (BGB) Stock, Above-ground Biomass (AGB) Stock, AGB Carbon Loss from Fire, BGB Carbon Loss from Fire, Deadwood Carbon Loss from Management, and Total Carbon Loss. The table also includes the area (annually) of each forest type in hectares: Atlantic white cedar Area (hectares); Cypress-gum Area (hectares); Maple-gum Area (hectares); Pond pine Area (hectares). Net ecosystem production for the Great Dismal Swamp (~ 54,000 ha), from 1985 to 2015 was estimated to be a net sink of 0.97 Tg C. When the hurricane and six historic fire events were modeled, the Great Dismal Swamp became a net source of 0.89 Tg C. The cumulative above and belowground C loss estimated from the South One in 2008 and Lateral West fire in 2011 totaled 1.70 Tg C, while management activities removed an additional 0.01 Tg C. The C loss in below-ground biomass alone totaled 1.38 Tg C, with the balance (0.31 Tg C

  5. The Role of Brain in Energy Balance.

    Science.gov (United States)

    Matafome, Paulo; Seiça, Raquel

    2017-01-01

    Energy homeostasis is regulated by homeostatic and nonhomeostatic reward circuits which are closely integrated and interrelated. Before, during, and after meals, peripheral nutritional signals, through hormonal and neuronal pathways, are conveyed to selective brain areas, namely the hypothalamic nuclei and the brainstem, the main brain areas for energy balance regulation. These orexigenic and anorexigenic centers are held responsible for the integration of those signals and for an adequate output to peripheral organs involved in metabolism and energy homeostasis.Feeding includes also a hedonic behavior defined as food intake for pleasure independently of energy requirement. This nonhomeostatic regulation of energy balance is based on food reward properties, unrelated to nutritional demands, and involves areas like mesolimbic reward system, such as the ventral tegmental area and the nucleus accumbens, and also opioid, endocannabinoid, and dopamine systems.Herein, focus will be put on the brain circuits of homeostatic and nonhomeostatic regulation of food intake and energy expenditure.

  6. Denmark's net'zero energy home'

    DEFF Research Database (Denmark)

    Hansen, Ellen Kathrine

    2010-01-01

    ; a trampoline sits on the neatly trimmed lawn. But this house is different. Using ecologically benign materials, a rooftop of solar panels, and energy-scrimping designs, the house generates more than enough power to run itself. Inside, a family of five is testing out the ultimate model home. Windows in all four...

  7. Energy balance of the lavender oil production

    Directory of Open Access Journals (Sweden)

    Osman GÖKDOĞAN

    2016-06-01

    Full Text Available This research was carried out to determine the energy input-output analysis of lavender oil production. Data from agricultural farms in Isparta province was used. Energy input was calculated as 1993.89 MJ and energy output was calculated as 2925.51 MJ. Wood energy, fresh stalked lavender flower energy, equipment energy, human labour energy, electricity energy, and water energy inputs were 54.22 %, 41.86 %, 3.40 %, 0.23 %, 0.18 %, and 0.10 % of energy inputs, respectively. In this production, it is noteworthy that wood was used as fuel in the lavender oil production distillation process as the highest input. In the energy outputs, an average of 3.10 kg lavender oil and 130 kg lavender water were extracted by processing 234 kg fresh stalked lavender flower. Energy use efficiency, specific energy, energy productivity, and net energy for lavender oil production were calculated as 1.47, 643.19 MJ kg-1, 0.002 kg MJ-1 and 931.62 MJ, respectively.

  8. Optimizing Existing Multistory Building Designs towards Net-Zero Energy

    Directory of Open Access Journals (Sweden)

    Mohammad Y. AbuGrain

    2017-03-01

    Full Text Available Recent global developments in awareness and concerns about environmental problems have led to reconsidering built environment approaches and construction techniques. One of the alternatives is the principle of low/zero-energy buildings. This study investigates the potentials of energy savings in an existing multi-story building in the Mediterranean region in order to achieve net-zero energy as a solution to increasing fossil fuel prices. The Colored building at the Faculty of Architecture, Eastern Mediterranean University, Cyprus was chosen as a target of this study to be investigated and analyzed in order to know how energy efficiency strategies could be applied to the building to reduce annual energy consumption. Since this research objective is to develop a strategy to achieve net-zero energy in existing buildings, case study and problem solving methodologies were applied in this research in order to evaluate the building design in a qualitative manner through observations, in addition to a quantitative method through an energy modeling simulation to achieve desirable results which address the problems. After optimizing the building energy performance, an alternative energy simulation was made of the building in order to make an energy comparison analysis, which leads to reliable conclusions. These methodologies and the strategies used in this research can be applied to similar buildings in order to achieve net-zero energy goals.

  9. Energy balance of dark anaerobic fermentation as a tool for sustainability analysis

    Energy Technology Data Exchange (ETDEWEB)

    Ruggeri, Bernardo; Tommasi, Tonia; Sassi, Guido [Dept. of Material Science and Chemical Engineering, Politecnico di Torino Corso Duca Degli Abruzzi 24, 10129 Turin (Italy)

    2010-10-15

    A process aimed at producing energy needs to produce more energy than the energy necessary to run the process itself in order to be energetically sustainable. In this paper, an energy balance of a batch anaerobic bioreactor has been defined and calculated, both for different operative conditions and for different reactor scales, in order to analyze the sustainability of hydrogen production through dark anaerobic fermentation. Energy production in the form of hydrogen and methane, energy to warm up the fermentation broth, energy loss during fermentation and energy for mixing and pumping have been considered in the energy balance. Experimental data and literature data for mesophilic microorganism consortia have been used to calculate the energy balance. The energy production of a mesophilic microorganism consortium in a batch reactor has been studied in the 16-50 C temperature range. The hydrogen batch dark fermentation resulted to only have a positive net production of energy over a minimal reactor dimension in summer conditions with an energy recovery strategy. The best working temperature resulted to be 20 C with 20% of available energy. Hydrogen batch dark fermentation may be coupled with other processes to obtain a positive net energy by recovering energy from the end products of hydrogen dark fermentation. As an example, methane fermentation has been considered to energetically valorize the end products of hydrogen fermentation. The combined process resulted in a positive net energy over the whole range of tested reactor dimension with 45-90% of available energy. (author)

  10. A Net Energy-based Analysis for a Climate-constrained Sustainable Energy Transition

    OpenAIRE

    Sgouridis, Sgouris; Bardi, Ugo; Csala, Denes

    2015-01-01

    The transition from a fossil-based energy economy to one based on renewable energy is driven by the double challenge of climate change and resource depletion. Building a renewable energy infrastructure requires an upfront energy investment that subtracts from the net energy available to society. This investment is determined by the need to transition to renewable energy fast enough to stave off the worst consequences of climate change and, at the same time, maintain a sufficient net energy fl...

  11. Summertime influences of tidal energy advection on the surface energy balance in a mangrove forest

    Directory of Open Access Journals (Sweden)

    J. G. Barr

    2013-01-01

    Full Text Available Mangrove forests are ecosystems susceptible to changing water levels and temperatures due to climate change as well as perturbations resulting from tropical storms. Numerical models can be used to project mangrove forest responses to regional and global environmental changes, and the reliability of these models depends on surface energy balance closure. However, for tidal ecosystems, the surface energy balance is complex because the energy transport associated with tidal activity remains poorly understood. This study aimed to quantify impacts of tidal flows on energy dynamics within a mangrove ecosystem. To address the research objective, an intensive 10-day study was conducted in a mangrove forest located along the Shark River in the Everglades National Park, FL, USA. Forest–atmosphere turbulent exchanges of energy were quantified with an eddy covariance system installed on a 30-m-tall flux tower. Energy transport associated with tidal activity was calculated based on a coupled mass and energy balance approach. The mass balance included tidal flows and accumulation of water on the forest floor. The energy balance included temporal changes in enthalpy, resulting from tidal flows and temperature changes in the water column. By serving as a net sink or a source of available energy, flood waters reduced the impact of high radiational loads on the mangrove forest. Also, the regression slope of available energy versus sink terms increased from 0.730 to 0.754 and from 0.798 to 0.857, including total enthalpy change in the water column in the surface energy balance for 30-min periods and daily daytime sums, respectively. Results indicated that tidal inundation provides an important mechanism for heat removal and that tidal exchange should be considered in surface energy budgets of coastal ecosystems. Results also demonstrated the importance of including tidal energy advection in mangrove biophysical models that are used for predicting ecosystem

  12. Glial cells and energy balance.

    Science.gov (United States)

    Argente-Arizón, Pilar; Guerra-Cantera, Santiago; Garcia-Segura, Luis Miguel; Argente, Jesús; Chowen, Julie A

    2017-01-01

    The search for new strategies and drugs to abate the current obesity epidemic has led to the intensification of research aimed at understanding the neuroendocrine control of appetite and energy expenditure. This intensified investigation of metabolic control has also included the study of how glial cells participate in this process. Glia, the most abundant cell type in the central nervous system, perform a wide spectrum of functions and are vital for the correct functioning of neurons and neuronal circuits. Current evidence indicates that hypothalamic glia, in particular astrocytes, tanycytes and microglia, are involved in both physiological and pathophysiological mechanisms of appetite and metabolic control, at least in part by regulating the signals reaching metabolic neuronal circuits. Glia transport nutrients, hormones and neurotransmitters; they secrete growth factors, hormones, cytokines and gliotransmitters and are a source of neuroprogenitor cells. These functions are regulated, as glia also respond to numerous hormones and nutrients, with the lack of specific hormonal signaling in hypothalamic astrocytes disrupting metabolic homeostasis. Here, we review some of the more recent advances in the role of glial cells in metabolic control, with a special emphasis on the differences between glial cell responses in males and females. © 2017 Society for Endocrinology.

  13. Effect of dietary net energy concentrations on growth performance and net energy intake of growing gilts.

    Science.gov (United States)

    Lee, Gang Il; Kim, Jong Hyuk; Han, Gi Ppeum; Koo, Do Yoon; Choi, Hyeon Seok; Kil, Dong Yong

    2017-09-01

    This experiment investigated the effect of dietary net energy (NE) concentrations on growth performance and NE intake of growing gilts. Five diets were formulated to contain 9.6, 10.1, 10.6, 11.1, and 11.6 MJ NE/kg, respectively. A metabolism trial with 10 growing pigs (average body weight [BW] = 15.9±0.24 kg) was conducted to determine NE concentrations of 5 diets based on French and Dutch NE systems in a 5×5 replicated Latin square design. A growth trial also was performed with five dietary treatments and 12 replicates per treatment using 60 growing gilts (average BW = 15.9±0.55 kg) for 28 days. A regression analysis was performed to predict daily NE intake from the BW of growing gilts. Increasing NE concentrations of diets did not influence average daily gain and average daily feed intake of growing gilts. There was a quadratic relationship (p = 0.01) between dietary NE concentrations and feed efficiency (G:F), although the difference in G:F among treatment means was relatively small. Regression analysis revealed that daily NE intake was linearly associated with the BW of growing gilts. The prediction equations for NE intake with the BW of growing gilts were: NE intake (MJ/d) = 1.442+(0.562×BW, kg), R 2 = 0.796 when French NE system was used, whereas NE intake (MJ/d) = 1.533+(0.614×BW, kg), R 2 = 0.810 when Dutch NE system was used. Increasing NE concentrations of diets from 9.6 to 11.6 MJ NE/kg have little impacts on growth performance of growing gilts. Daily NE intake can be predicted from the BW between 15 and 40 kg in growing gilts.

  14. Energy Dependence of Moments of Net-Proton, Net-Kaon, and Net-Charge Multiplicity Distributions at STAR

    CERN Document Server

    ,

    2016-01-01

    One of the main goals of the RHIC Beam Energy Scan (BES) program is to study the QCD phase structure, which includes the search for the QCD critical point, over a wide range of chemical potential. Theoretical calculations predict that fluctuations of conserved quantities, such as baryon number (B), charge (Q), and strangeness (S), are sensitive to the correlation length of the dynamical system. Experimentally, higher moments of multiplicity distributions have been utilized to search for the QCD critical point in heavy-ion collisions. In this paper, we report recent efficiency-corrected cumulants and cumulants ratios of the net- proton, net-kaon, and net-charge multiplicity distributions in Au+Au collisions at 7.7, 11.5, 14.5, 19.6, 27, 39, 62.4, and 200 GeV collected in the years 2010, 2011, and 2014 with STAR at RHIC. The centrality and energy dependence of the cumulants up to the fourth order, as well as their ratios, are presented. Furthermore, the comparisons with baseline calculations (Poisson) and non-c...

  15. Heat Mismatch of future Net Zero Energy Buildings within district heating areas in Denmark

    DEFF Research Database (Denmark)

    Nielsen, Steffen; Möller, Bernd

    . NZEBs are characterized by having a greatly reduced energy demand that on an annual basis can be balanced out by an equivalent generation of energy from RES. Most buildings in Denmark are connected electricity grids and around half to district heating (DH) systems. Connecting buildings to larger energy...... instead of wasting the energy. The objective in this paper is find how large an area of NZEBs is to be built within DH areas and how the heat mismatch of NZEBs influence different types of Danish DH systems. In the analyses nine different scenarios are analyzed. The examination is from a technical......The long-term goal for Denmark is to develop an energy system solely based on renewable energy sources (RES) in 2050. To reach this goal energy savings in buildings are essential. Therefore, a focus on energy efficient measures in buildings and net zero energy buildings (NZEBs) have increased...

  16. Balancing the Energy-Water Nexus

    Energy Technology Data Exchange (ETDEWEB)

    Dell, Jan

    2010-09-15

    Optimizing the complex tradeoffs in the Energy-Water Nexus requires quantification of energy use, carbon emitted and water consumed. Water is consumed in energy production and is often a constraint to operations. More global attention and investment has been made on reducing carbon emissions than on water management. Review of public reporting by the largest 107 global power producers and 50 companies in the oil/gas industry shows broad accounting on carbon emissions but only partial reporting on water consumption metrics. If the Energy-Water Nexus is to be balanced, then water must also be measured to be optimally managed with carbon emissions.

  17. Kisspeptin and energy balance in reproduction.

    Science.gov (United States)

    De Bond, Julie-Ann P; Smith, Jeremy T

    2014-03-01

    Kisspeptin is vital for the neuroendocrine regulation of GNRH secretion. Kisspeptin neurons are now recognized as a central pathway responsible for conveying key homeostatic information to GNRH neurons. This pathway is likely to mediate the well-established link between energy balance and reproductive function. Thus, in states of severely altered energy balance (either negative or positive), fertility is compromised, as is Kiss1 expression in the arcuate nucleus. A number of metabolic modulators have been proposed as regulators of kisspeptin neurons including leptin, ghrelin, pro-opiomelanocortin (POMC), and neuropeptide Y (NPY). Whether these regulate kisspeptin neurons directly or indirectly will be discussed. Moreover, whether the stimulatory role of leptin on reproduction is mediated by kisspeptin directly will be questioned. Furthermore, in addition to being expressed in GNRH neurons, the kisspeptin receptor (Kiss1r) is also expressed in other areas of the brain, as well as in the periphery, suggesting alternative roles for kisspeptin signaling outside of reproduction. Interestingly, kisspeptin neurons are anatomically linked to, and can directly excite, anorexigenic POMC neurons and indirectly inhibit orexigenic NPY neurons. Thus, kisspeptin may have a direct role in regulating energy balance. Although data from Kiss1r knockout and WT mice found no differences in body weight, recent data indicate that kisspeptin may still play a role in food intake and glucose homeostasis. Thus, in addition to regulating reproduction, and mediating the effect of energy balance on reproductive function, kisspeptin signaling may also be a direct regulator of metabolism.

  18. Solar energy resources not accounted in Brazilian National Energy Balance

    Energy Technology Data Exchange (ETDEWEB)

    Pinheiro, Paulo Cesar da Costa [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Dept. de Engenharia Mecanica], Emails: pinheiro@netuno.Lcc.ufmg.br, pinheiro@demec.ufmg.br

    2009-07-01

    The main development vector of a society is the energy. The solar energy is the main energy source on the planet earth. Brazil is a tropical country, and the incident solar energy on its soil (15 trillion MWh/year) is 20,000 times its annual oil production. Several uses of solar energy are part of our lives in a so natural way that it despised in the consumption and use energy balance. In Brazil, solar energy is used directly in many activities and not accounted for in Energy Balance (BEN 2007), consisting of a virtual power generation. This work aims to make a preliminary assessment of solar energy used in different segments of the Brazilian economy. (author)

  19. Targeting Net Zero Energy at Fort Carson: Assessment and Recommendations

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, K.; Markel, T.; Simpson, M.; Leahey, J.; Rockenbaugh, C.; Lisell, L.; Burman, K.; Singer, M.

    2011-10-01

    The U.S. Army's Fort Carson installation was selected to serve as a prototype for net zero energy assessment and planning. NREL performed the comprehensive assessment to appraise the potential of Fort Carson to achieve net zero energy status through energy efficiency, renewable energy, and electric vehicle integration. This report summarizes the results of the assessment and provides energy recommendations. This study is part of a larger cross-laboratory effort that also includes an assessment of renewable opportunities at seven other DoD Front Range installations, a microgrid design for Fort Carson critical loads and an assessment of regulatory and market-based barriers to a regional secure smart grid.

  20. The sower’s way: quantifying the narrowing net-energy pathways to a global energy transition

    Science.gov (United States)

    Sgouridis, Sgouris; Csala, Denes; Bardi, Ugo

    2016-09-01

    Planning the appropriate renewable energy (RE) installation rate should balance two partially contradictory objectives: substituting fossil fuels fast enough to stave-off the worst consequences of climate change while maintaining a sufficient net energy flow to support the world’s economy. The upfront energy invested in constructing a RE infrastructure subtracts from the net energy available for societal energy needs, a fact typically neglected in energy projections. Modeling feasible energy transition pathways to provide different net energy levels we find that they are critically dependent on the fossil fuel emissions cap and phase-out profile and on the characteristic energy return on energy invested of the RE technologies. The easiest pathway requires installation of RE plants to accelerate from 0.12 TWp yr-1 in 2013 to peak between 7.3 and 11.6 TWp yr-1 in the late 2030s, for an early or a late fossil-fuel phase-out respectively in order for emissions to stay within the recommended CO2 budget.

  1. Nexus of poverty, energy balance and health.

    Science.gov (United States)

    Mishra, C P

    2012-04-01

    Since the inception of planning process in India, health planning was an integral component of socio-economic planning. Recommendations of several committees, policy documents and Millennium development goals were instrumental in development of impressive health infrastructure. Several anti-poverty and employment generation programmes were instituted to remove poverty. Spectacular achievements took place in terms of maternal and child health indicators and expectancy of life at birth. However, communicable diseases and undernutrition remain cause of serious concern and non-communicable diseases are imposing unprecedented challenge to planners and policy makers. Estimates of poverty based on different criteria point that it has remained a sustained problem in the country and emphasizes on revisiting anti-poverty programmes, economic policies and social reforms. Poverty affects purchasing power and thereby, food consumption. Energy intake data has inherent limitations. It must be assessed in terms of energy expenditure. Energy balance has been least explored area of research. The studies conducted in three different representative population group of Eastern Uttar Pradesh revealed that 69.63% rural adolescent girls (10-19 years), 79.9% rural reproductive age group females and 62.3% rural geriatric subjects were in negative energy balance. Negative energy balance was significantly less in adolescent girls belonging to high SES (51.37%), having main occupation of family as business (55.3%), and highest per capita income group (57.1%) with respect to their corresponding sub-categories. In case of rural reproductive age groups, this was maximum (93.0%) in SC/ST category and least (65.7%) in upper caste group. In case of geriatric group, higher adjusted Odd's Ratio for negative energy balance for subjects not cared by family members (AOR 23.43, CI 3.93-139.56), not kept money (AOR 5.27, CI 1.58-17.56), belonging to lower and upper middle SES by Udai Pareekh Classification

  2. Nexus of poverty, energy balance and health

    Directory of Open Access Journals (Sweden)

    C P Mishra

    2012-01-01

    Full Text Available Since the inception of planning process in India, health planning was an integral component of socio-economic planning. Recommendations of several committees, policy documents and Millennium development goals were instrumental in development of impressive health infrastructure. Several anti-poverty and employment generation programmes were instituted to remove poverty. Spectacular achievements took place in terms of maternal and child health indicators and expectancy of life at birth. However, communicable diseases and undernutrition remain cause of serious concern and non-communicable diseases are imposing unprecedented challenge to planners and policy makers. Estimates of poverty based on different criteria point that it has remained a sustained problem in the country and emphasizes on revisiting anti-poverty programmes, economic policies and social reforms. Poverty affects purchasing power and thereby, food consumption. Energy intake data has inherent limitations. It must be assessed in terms of energy expenditure. Energy balance has been least explored area of research. The studies conducted in three different representative population group of Eastern Uttar Pradesh revealed that 69.63% rural adolescent girls (10-19 years, 79.9% rural reproductive age group females and 62.3% rural geriatric subjects were in negative energy balance. Negative energy balance was significantly less in adolescent girls belonging to high SES (51.37%, having main occupation of family as business (55.3%, and highest per capita income group (57.1% with respect to their corresponding sub-categories. In case of rural reproductive age groups, this was maximum (93.0% in SC/ST category and least (65.7% in upper caste group. In case of geriatric group, higher adjusted Odd′s Ratio for negative energy balance for subjects not cared by family members (AOR 23.43, CI 3.93-139.56, not kept money (AOR 5.27, CI 1.58-17.56, belonging to lower and upper middle SES by Udai Pareekh

  3. Nexus of Poverty, Energy Balance and Health

    Science.gov (United States)

    Mishra, C. P.

    2012-01-01

    Since the inception of planning process in India, health planning was an integral component of socio-economic planning. Recommendations of several committees, policy documents and Millennium development goals were instrumental in development of impressive health infrastructure. Several anti-poverty and employment generation programmes were instituted to remove poverty. Spectacular achievements took place in terms of maternal and child health indicators and expectancy of life at birth. However, communicable diseases and undernutrition remain cause of serious concern and non-communicable diseases are imposing unprecedented challenge to planners and policy makers. Estimates of poverty based on different criteria point that it has remained a sustained problem in the country and emphasizes on revisiting anti-poverty programmes, economic policies and social reforms. Poverty affects purchasing power and thereby, food consumption. Energy intake data has inherent limitations. It must be assessed in terms of energy expenditure. Energy balance has been least explored area of research. The studies conducted in three different representative population group of Eastern Uttar Pradesh revealed that 69.63% rural adolescent girls (10-19 years), 79.9% rural reproductive age group females and 62.3% rural geriatric subjects were in negative energy balance. Negative energy balance was significantly less in adolescent girls belonging to high SES (51.37%), having main occupation of family as business (55.3%), and highest per capita income group (57.1%) with respect to their corresponding sub-categories. In case of rural reproductive age groups, this was maximum (93.0%) in SC/ST category and least (65.7%) in upper caste group. In case of geriatric group, higher adjusted Odd's Ratio for negative energy balance for subjects not cared by family members (AOR 23.43, CI 3.93-139.56), not kept money (AOR 5.27, CI 1.58-17.56), belonging to lower and upper middle SES by Udai Pareekh Classification

  4. Effects of Supplemental Energy on Protein Balance during 4-d Arctic Military Training.

    Science.gov (United States)

    Margolis, Lee M; Murphy, Nancy E; Martini, Svein; Gundersen, Yngvar; Castellani, John W; Karl, J Philip; Carrigan, Christopher T; Teien, Hilde-Kristin; Madslien, Elisabeth-Henie; Montain, Scott J; Pasiakos, Stefan M

    2016-08-01

    Soldiers often experience negative energy balance during military operations that diminish whole-body protein retention, even when dietary protein is consumed within recommended levels (1.5-2.0 g·kg·d). The objective of this study is to determine whether providing supplemental nutrition spares whole-body protein by attenuating the level of negative energy balance induced by military training and to assess whether protein balance is differentially influenced by the macronutrient source. Soldiers participating in 4-d arctic military training (AMT) (51-km ski march) were randomized to receive three combat rations (CON) (n = 18), three combat rations plus four 250-kcal protein-based bars (PRO, 20 g protein) (n = 28), or three combat rations plus four 250-kcal carbohydrate-based bars daily (CHO, 48 g carbohydrate) (n = 27). Energy expenditure (D2O) and energy intake were measured daily. Nitrogen balance (NBAL) and protein turnover were determined at baseline (BL) and day 3 of AMT using 24-h urine and [N]-glycine. Protein and carbohydrate intakes were highest (P energy intake above CON. Energy expenditure (6155 ± 515 kcal·d), energy balance (-3313 ± 776 kcal·d), net protein balance (NET) (-0.24 ± 0.60 g·d), and NBAL (-68.5 ± 94.6 mg·kg·d) during AMT were similar between groups. In the combined cohort, energy intake was associated (P energy intake (3723 ± 359 kcal·d, 2.11 ± 0.45 g protein·kg·d, 6.654 ± 1.16 g carbohydrate·kg·d) achieved net protein balance and NBAL during AMT. These data reinforce the importance of consuming sufficient energy during periods of high energy expenditure to mitigate the consequences of negative energy balance and attenuate whole-body protein loss.

  5. Net energy levels on the lipid profile of pork

    Directory of Open Access Journals (Sweden)

    Stephan Alexander da Silva Alencar

    2017-09-01

    Full Text Available ABSTRACT: This study was conducted to evaluate the effects of net energy levels on the lipid profile of adipose tissue and muscle of swines. A total of 90 animals, with initial weight of 71.94±4.43kg, were used, and distributed in a randomized block design in five net energy levels (2,300, 2,425, 2,550, 2,675, and 2,800Kcal kg-1 feed, with nine replicates and two animals per experimental unit. Lipid profiles of adipose tissue and muscle were analyzed using gas chromatography. Increasing the levels of net energy using soybean oil, improved the lipid profile of adipose tissue and muscle, increased linearly (P<0.05 the concentrations of polyunsaturated fatty acids, especially linoleic and α-linolenic acid, reduced linearly (P<0.05 the monounsaturated and saturated fatty acids and omega 6: omega 3. In adipose tissue was observed linear reduction (P<0.05 of atherogenic and thrombogenic indexes. In conclusion, increasing the level of net energy of the diet using soybean oil improved the lipid profile of adipose tissue and muscle.

  6. Net energy production associated with pathogen inactivation during mesophilic and thermophilic anaerobic digestion of sewage sludge.

    Science.gov (United States)

    Ziemba, Christopher; Peccia, Jordan

    2011-10-15

    The potential for anaerobic digester energy production must be balanced with the sustainability of reusing the resultant biosolids for land application. Mesophilic, thermophilic, temperature-phased, and high temperature (60 or 70 °C) batch pre-treatment digester configurations have been systematically evaluated for net energy production and pathogen inactivation potential. Energy input requirements and net energy production were modeled for each digester scheme. First-order inactivation rate coefficients for Escherichia coli, Enterococcus faecalis and bacteriophage MS-2 were measured at each digester temperature and full-scale pathogen inactivation performance was estimated for each indicator organism and each digester configuration. Inactivation rates were found to increase dramatically at temperatures above 55 °C. Modeling full-scale performance using retention times based on U.S. EPA time and temperature constraints predicts a 1-2 log inactivation in mesophilic treatment, and a 2-5 log inactivation in 50-55 °C thermophilic and temperature-phased treatments. Incorporating a 60 or 70 °C batch pre-treatment phase resulted in dramatically higher potency, achieving MS-2 inactivation of 14 and 16 logs respectively, and complete inactivation (over 100 log reduction) of E. coli and E. faecalis. For temperatures less than 70 °C, viability staining of thermally-treated E. coli showed significantly reduced inactivation relative to standard culture enumeration. Due to shorter residence times in thermophilic reactors, the net energy production for all digesters was similar (less than 20% difference) with the 60 or 70 °C batch treatment configurations producing the most net energy and the mesophilic treatment producing the least. Incorporating a 60 or 70 °C pre-treatment phase can dramatically increase pathogen inactivation performance without decreasing net energy capture from anaerobic digestion. Energy consumption is not a significant barrier against

  7. Balancing Energy Processes in Turbine Engines

    Directory of Open Access Journals (Sweden)

    Balicki Włodzimierz

    2015-01-01

    Full Text Available The article discusses the issue of balancing energy processes in turbine engines in operation in aeronautic and marine propulsion systems with the aim to analyse and evaluate basic operating parameters. The first part presents the problem of enormous amounts of energy needed for driving fans and compressors of the largest contemporary turbofan engines commonly used in long-distance aviation. The amounts of the transmitted power and the effect of flow parameters and constructional properties of the engines on their performance and real efficiency are evaluated. The second part of the article, devoted to marine applications of turbine engines, presents the energy balance of the kinetic system of torque transmission from main engine turbines to screw propellers in the combined system of COGAG type. The physical model of energy conversion processes executed in this system is presented, along with the physical model of gasodynamic processes taking place in a separate driving turbine of a reversing engine. These models have made the basis for formulating balance equations, which then were used for analysing static and dynamic properties of the analysed type of propulsion, in particular in the aspect of mechanical loss evaluation in its kinematic system.

  8. Feasibility of Achieving a Zero-Net-Energy, Zero-Net-Cost Homes

    Energy Technology Data Exchange (ETDEWEB)

    Al-Beaini, S.; Borgeson, S.; Coffery, B.; Gregory, D.; Konis, K.; Scown, C.; Simjanovic, J.; Stanley, J.; Strogen, B.; Walker, I.

    2009-09-01

    A green building competition, to be known as the Energy Free Home Challenge (EFHC), is scheduled to be opened to teams around the world in 2010. This competition will encourage both design innovation and cost reduction, by requiring design entries to meet 'zero net energy' and 'zero net cost' criteria. For the purposes of this competition, a 'zero net energy' home produces at least as much energy as it purchases over the course of a year, regardless of the time and form of the energy (e.g., electricity, heat, or fuel) consumed or produced. A 'zero net cost' home is no more expensive than a traditional home of comparable size and comfort, when evaluated over the course of a 30-year mortgage. In other words, the 'green premium' must have a payback period less than 30 years, based on the value of energy saved. The overarching goal of the competition is to develop affordable, high-performance homes that can be mass-produced at a large scale, and are able to meet occupant needs in harsh climates (as can be found where the competition will be held in Illinois). This report outlines the goals of the competition, and gauges their feasibility using both modeling results and published data. To ensure that the established rules are challenging, yet reasonable, this report seeks to refine the competition goals after exploring their feasibility through case studies, cost projections, and energy modeling. The authors of this report conducted a survey of the most progressive home energy-efficiency practices expected to appear in competition design submittals. In Appendix A, a summary can be found of recent projects throughout the United States, Canada, Germany, Switzerland, Sweden and Japan, where some of the most progressive technologies have been implemented. As with past energy efficient home projects, EFHC competitors will incorporate a multitude of energy efficiency measures into their home designs. The authors believe that

  9. Sustainable Urban Regeneration Based on Energy Balance

    Directory of Open Access Journals (Sweden)

    Sacha Silvester

    2012-07-01

    Full Text Available In this paper, results are reported of a technology assessment of the use and integration of decentralized energy systems and storage devices in an urban renewal area. First the general context of a different approach based on 'rethinking' and the incorporation of ongoing integration of coming economical and environmental interests on infrastructure, in relation to the sustainable urban development and regeneration from the perspective of the tripod people, technology and design is elaborated. However, this is at different scales, starting mainly from the perspective of the urban dynamics. This approach includes a renewed look at the ‘urban metabolism’ and the role of environmental technology, urban ecology and environment behavior focus. Second, the potential benefits of strategic and balanced introduction and use of decentralized devices and electric vehicles (EVs, and attached generation based on renewables are investigated in more detail in the case study of the ‘Merwe-Vierhaven’ area (MW4 in the Rotterdam city port in the Netherlands. In order to optimize the energy balance of this urban renewal area, it is found to be impossible to do this by tuning the energy consumption. It is more effective to change the energy mix and related infrastructures. However, the problem in existing urban areas is that often these areas are restricted to a few energy sources due to lack of available space for integration. Besides this, energy consumption in most cases is relatively concentrated in (existing urban areas. This limits the potential of sustainable urban regeneration based on decentralized systems, because there is no balanced choice regarding the energy mix based on renewables and system optimization. Possible solutions to obtain a balanced energy profile can come from either the choice to not provide all energy locally, or by adding different types of storage devices to the systems. The use of energy balance based on renewables as a

  10. Greenhouse gas emissions and energy balance of palm oil biofuel

    Energy Technology Data Exchange (ETDEWEB)

    de Souza, Simone Pereira; Pacca, Sergio [Graduate Program on Environmental Engineering Science, School of Engineering of Sao Carlos, University of Sao Paulo, Rua Arlindo Bettio, 1000 Sao Paulo (Brazil); de Avila, Marcio Turra; Borges, Jose Luiz B. [Brazilian Agricultural Research Corporation (Embrapa - Soja) (Brazil)

    2010-11-15

    based on the information provided by other authors resulted in 2406 kg CO{sub 2}e/ha, on average. The Angarita et al. (2009) [Angarita EE, Lora EE, Costa RE, Torres EA. The energy balance in the palm oil-derived methyl ester (PME) life cycle for the cases in Brazil and Colombia. Renewable Energy 2009;34:2905-13] study does not report emissions. When compared to diesel on a energy basis, avoided emissions due to the use of biodiesel account for 80 g CO{sub 2}e/MJ. Thus, avoided life cycle emissions associated with the use of biodiesel yield a net reduction of greenhouse gas emissions. We also assessed the carbon balance between a palm tree plantation, including displaced emissions from diesel, and a natural ecosystem. Considering the carbon balance outcome plus life cycle emissions the payback time for a tropical forest is 39 years. The result published by Gibbs et al. (2008) [Gibbs HK, Johnston M, Foley JA, Holloway T, Monfreda C, Ramankutty N, et al., Carbon payback times for crop-based biofuel expansion in the tropics: the effects of changing yield and technology. Environmental Research Letters 2008;3:10], which ignores life cycle emissions, determined a payback range for biodiesel production between 30 and 120 years. (author)

  11. Energy-balanced algorithm for RFID estimation

    Science.gov (United States)

    Zhao, Jumin; Wang, Fangyuan; Li, Dengao; Yan, Lijuan

    2016-10-01

    RFID has been widely used in various commercial applications, ranging from inventory control, supply chain management to object tracking. It is necessary for us to estimate the number of RFID tags deployed in a large area periodically and automatically. Most of the prior works use passive tags to estimate and focus on designing time-efficient algorithms that can estimate tens of thousands of tags in seconds. But for a RFID reader to access tags in a large area, active tags are likely to be used due to their longer operational ranges. But these tags use their own battery as energy supplier. Hence, conserving energy for active tags becomes critical. Some prior works have studied how to reduce energy expenditure of a RFID reader when it reads tags IDs. In this paper, we study how to reduce the amount of energy consumed by active tags during the process of estimating the number of tags in a system and make the energy every tag consumed balanced approximately. We design energy-balanced estimation algorithm that can achieve our goal we mentioned above.

  12. Obesity and Energy Balance in GI Cancer.

    Science.gov (United States)

    Brown, Justin C; Meyerhardt, Jeffrey A

    2016-12-10

    The prevalence of overweight (body mass index [BMI], 25 to 29.9 kg/m(2)) and obesity (BMI ≥ 30 kg/m(2)) have increased dramatically in the United States. Because increasing BMI is associated with the development of multiple different cancer types, including most GI cancers, providers will frequently encounter patients with GI cancer who are overweight or obese. Mounting evidence associates overweight and/or obesity with worsened prognosis in multiple GI cancers, including esophageal, gastric, hepatocellular, pancreatic, and colorectal. However, these data are observational and may be subject to bias and/or confounding. Furthermore, in some cancer types, the associations between BMI and outcomes is not linear, where overweight and class I obese patients may have an improvement in outcome. This report provides a brief highlight of existing studies that have linked overweight and/or obesity to prognosis in GI cancer; provides recommendations on best management practices; and discusses limitations, controversies, and future directions in this rapidly evolving area. There are multiple areas of promise that warrant continued investigation: What are the comparative contributions of energy balance, including weight, dietary patterns, and physical activity on cancer prognosis? What are the specific physiologic pathways that mediate the relationship between energy balance and prognosis? What is the relationship between low muscle mass (sarcopenia) or sarcopenic obesity and cancer prognosis? Are there subsets of patients for whom purposefully altering energy balance would be deleterious to prognosis? This area is rich with opportunities to understand how states of energy (im)balance can be favorably altered to promote healthy survivorship.

  13. Obesity and Energy Balance in GI Cancer

    Science.gov (United States)

    Meyerhardt, Jeffrey A.

    2016-01-01

    The prevalence of overweight (body mass index [BMI], 25 to 29.9 kg/m2) and obesity (BMI ≥ 30 kg/m2) have increased dramatically in the United States. Because increasing BMI is associated with the development of multiple different cancer types, including most GI cancers, providers will frequently encounter patients with GI cancer who are overweight or obese. Mounting evidence associates overweight and/or obesity with worsened prognosis in multiple GI cancers, including esophageal, gastric, hepatocellular, pancreatic, and colorectal. However, these data are observational and may be subject to bias and/or confounding. Furthermore, in some cancer types, the associations between BMI and outcomes is not linear, where overweight and class I obese patients may have an improvement in outcome. This report provides a brief highlight of existing studies that have linked overweight and/or obesity to prognosis in GI cancer; provides recommendations on best management practices; and discusses limitations, controversies, and future directions in this rapidly evolving area. There are multiple areas of promise that warrant continued investigation: What are the comparative contributions of energy balance, including weight, dietary patterns, and physical activity on cancer prognosis? What are the specific physiologic pathways that mediate the relationship between energy balance and prognosis? What is the relationship between low muscle mass (sarcopenia) or sarcopenic obesity and cancer prognosis? Are there subsets of patients for whom purposefully altering energy balance would be deleterious to prognosis? This area is rich with opportunities to understand how states of energy (im)balance can be favorably altered to promote healthy survivorship. PMID:27903148

  14. Dissolved carbon leaching from soil is a crucial component of the net ecosystem carbon balance

    DEFF Research Database (Denmark)

    Kindler, Reimo; Siemens, Jan; Kaiser, Klaus

    2011-01-01

    Estimates of carbon leaching losses from different land use systems are few and their contribution to the net ecosystem carbon balance is uncertain. We investigated leaching of dissolved organic carbon (DOC), dissolved inorganic carbon (DIC), and dissolved methane (CH4), at forests, grasslands......, and croplands across Europe. Biogenic contributions to DIC were estimated by means of its d13C signature. Leaching of biogenic DIC was 8.34.9 gm2 yr1 for forests, 24.17.2 gm2 yr1 for grasslands, and 14.64.8 gm2 yr1 for croplands. DOC leaching equalled 3.51.3 gm2 yr1 for forests, 5.32.0 gm2 yr1 for grasslands...... ecosystem exchange (NEE) plus carbon inputs with fertilization minus carbon removal with harvest. Carbon leaching increased the net losses from cropland soils by 24–105% (median: 25%). For the majority of forest sites, leaching hardly affected actual net ecosystem carbon balances because of the small...

  15. BASIC program calculates flue gas energy balance

    Energy Technology Data Exchange (ETDEWEB)

    Ganapathy, V. (ABCO Industries, Inc., Abilene, TX (United States))

    1993-10-01

    Engineers always seek cost-cutting, energy-efficient ways to operate boilers and waste-heat recovery systems. The starting point in the design or performance evaluation of any heat transfer equipment is an energy balance calculation. This easy-to-use BASIC program tackles this problem. Using the gas stream analysis as percent weight or volume, the program calculates inlet and exit temperatures, heat duty, the gas stream's molecular weight, etc. This program is a definite must for the plant engineering notebook.

  16. The Influence of Rain Sensible Heat and Subsurface Energy Transport on the Energy Balance at the Land Surface

    NARCIS (Netherlands)

    Kollet, S.J.; Cvijanovic, I.; Schüttemeyer, D.; Maxwell, R.M.; Moene, A.F.; Bayer, P.

    2009-01-01

    In land surface models, which account for the energy balance at the land surface, subsurface heat transport is an important component that reciprocally influences ground, sensible, and latent heat fluxes and net radiation. In most models, subsurface heat transport parameterizations are commonly

  17. Carbon and energy balances for a range of biofuels options

    Energy Technology Data Exchange (ETDEWEB)

    Elsayed, M.A.; Matthews, R.; Mortimer, N.D.

    2003-03-01

    This is the final report of a project to produce a set of baseline energy and carbon balances for a range of electricity, heat and transport fuel production systems based on biomass feedstocks. A list of 18 important biofuel technologies in the UK was selected for study of their energy and carbon balances in a consistent approach. Existing studies on these biofuel options were reviewed and their main features identified in terms of energy input, greenhouse gas emissions (carbon dioxide, methane, nitrous oxide and total), transparency and relevance. Flow charts were produced to represent the key stages of the production of biomass and its conversion to biofuels. Outputs from the study included primary energy input per delivered energy output, carbon dioxide outputs per delivered energy output, methane output per delivered energy output, nitrous oxide output per delivered energy output and total greenhouse gas requirements. The net calorific value of the biofuel is given where relevant. Biofuels studied included: biodiesel from oilseed rape and recycled vegetable oil; combined heat and power (CHP) by combustion of wood chip from forestry residues; CHP by gasification of wood chip from short rotation coppice; electricity from the combustion of miscanthus, straw, wood chip from forestry residues and wood chip from short rotation coppice; electricity from gasification of wood chip from forestry residues and wood chip from short rotation coppice; electricity by pyrolysis of wood chip from forestry residues and wood chip from short rotation coppice; ethanol from lignocellulosics, sugar beet and wheat; heat (small scale) from combustion of wood chip from forestry residues and wood chip from short rotation coppice; and rapeseed oil from oilseed rape.

  18. The Energy Balance Study: The Design and Baseline Results for a Longitudinal Study of Energy Balance

    Science.gov (United States)

    Hand, Gregory A.; Shook, Robin P.; Paluch, Amanda E.; Baruth, Meghan; Crowley, E. Patrick; Jaggers, Jason R.; Prasad, Vivek K.; Hurley, Thomas G.; Hebert, James R.; O'Connor, Daniel P.; Archer, Edward; Burgess, Stephanie; Blair, Steven N.

    2013-01-01

    Purpose: The Energy Balance Study (EBS) was a comprehensive study designed to determine over a period of 12 months the associations of caloric intake and energy expenditure on changes in body weight and composition in a population of healthy men and women. Method: EBS recruited men and women aged 21 to 35 years with a body mass index between 20…

  19. The energy balance experiment EBEX-2000. Part III: Behaviour and quality of the radiation measurements

    NARCIS (Netherlands)

    Kohsiek, W.; Liebethal, C.; Foken, T.; Vogt, R.; Oncley, S.P.; Bernhofer, C.; Debruin, H.A.R.

    2007-01-01

    An important part of the Energy Balance Experiment (EBEX-2000) was the measurement of the net radiation and its components. Since the terrain, an irrigated cotton field, could not be considered homogeneous, radiation measurements were made at nine sites using a variety of radiation instruments,

  20. Energy intensity ratios as net energy measures of United States energy production and expenditures

    Science.gov (United States)

    King, C. W.

    2010-10-01

    In this letter I compare two measures of energy quality, energy return on energy invested (EROI) and energy intensity ratio (EIR) for the fossil fuel consumption and production of the United States. All other characteristics being equal, a fuel or energy system with a higher EROI or EIR is of better quality because more energy is provided to society. I define and calculate the EIR for oil, natural gas, coal, and electricity as measures of the energy intensity (units of energy divided by money) of the energy resource relative to the energy intensity of the overall economy. EIR measures based upon various unit prices for energy (e.g. /Btu of a barrel of oil) as well as total expenditures on energy supplies (e.g. total dollars spent on petroleum) indicate net energy at different points in the supply chain of the overall energy system. The results indicate that EIR is an easily calculated and effective proxy for EROI for US oil, gas, coal, and electricity. The EIR correlates well with previous EROI calculations, but adds additional information on energy resource quality within the supply chain. Furthermore, the EIR and EROI of oil and gas as well as coal were all in decline for two time periods within the last 40 years, and both time periods preceded economic recessions.

  1. Body composition and net energy requirements of Brazilian Somali lambs

    Directory of Open Access Journals (Sweden)

    Elzânia S. Pereira

    2014-12-01

    Full Text Available The aim of this study was to determine the energy requirements for maintenance (NEm and growth of 48 Brazilian Somali ram lambs with an average initial body weight of 13.47±1.76 kg. Eight animals were slaughtered at the trials beginning as a reference group to estimate the initial empty body weight (EBW and body composition. The remaining animals were assigned to a randomised block design with eight replications per block and five diets with increasing metabolisable energy content (4.93, 8.65, 9.41, 10.12 and 11.24 MJ/kg dry matter. The logarithm of heat production was regressed against metabolisable energy intake (MEI, and the NEm (kJ/kg0.75 EBW/day were estimated by extrapolation, when MEI was set at zero. The NEm was 239.77 kJ/kg0.75 EBW/day. The animal’s energy and EBW fat contents increased from 11.20 MJ/kg and 208.54 g/kg to 13.54 MJ/kg and 274.95 g/kg of EBW, respectively, as the BW increased from 13 to 28.70 kg. The net energy requirements for EBW gain increased from 13.79 to 16.72 MJ/kg EBW gain for body weights of 13 and 28.70 kg. Our study indicated the net energy requirements for maintenance in Brazilian Somali lambs were similar to the values commonly recommended by the United States’ nutritional system, but lower than the values recommended by Agricultural Research Council and Commonwealth Scientific and Industrial Research Organization. Net requirements for weight gain were less compared to the values commonly recommended by nutritional system of the United States.

  2. Dorsomedial hypothalamic NPY and energy balance control.

    Science.gov (United States)

    Bi, Sheng; Kim, Yonwook J; Zheng, Fenping

    2012-12-01

    Neuropeptide Y (NPY) is a potent hypothalamic orexigenic peptide. Within the hypothalamus, Npy is primarily expressed in the arcuate nucleus (ARC) and the dorsomedial hypothalamus (DMH). While the actions of ARC NPY in energy balance control have been well studied, a role for DMH NPY is still being unraveled. In contrast to ARC NPY that serves as one of downstream mediators of actions of leptin in maintaining energy homeostasis, DMH NPY is not under the control of leptin. Npy gene expression in the DMH is regulated by brain cholecystokinin (CCK) and other yet to be identified molecules. The findings of DMH NPY overexpression or induction in animals with increased energy demands and in certain rodent models of obesity implicate a role for DMH NPY in maintaining energy homeostasis. In support of this view, adeno-associated virus (AAV)-mediated overexpression of NPY in the DMH causes increases in food intake and body weight and exacerbates high-fat diet-induced hyperphagia and obesity. Knockdown of NPY in the DMH via AAV-mediated RNAi ameliorates hyperphagia, obesity and glucose intolerance of Otsuka Long-Evans Tokushima Fatty rats in which DMH NPY overexpression has been proposed to play a causal role. NPY knockdown in the DMH also prevents high-fat diet-induced hyperphagia, obesity and impaired glucose homeostasis. A detailed examination of actions of DMH NPY reveals that DMH NPY specifically affects nocturnal meal size and produces an inhibitory action on within meal satiety signals. In addition, DMH NPY modulates energy expenditure likely through affecting brown adipocyte formation and thermogenic activity. Overall, the recent findings provide clear evidence demonstrating critical roles for DMH NPY in energy balance control, and also imply a potential role for DMH NPY in maintaining glucose homeostasis. Copyright © 2012 Elsevier Ltd. All rights reserved.

  3. 40 CFR 73.83 - Secretary of Energy's action on net income neutrality applications.

    Science.gov (United States)

    2010-07-01

    ... Renewable Energy Reserve § 73.83 Secretary of Energy's action on net income neutrality applications. (a) First come, first served. The Secretary of Energy will process and certify net income neutrality... of Energy determines that the net income neutrality certification application does not meet the...

  4. Comprehensive Assessments of Energy Balance in Mice.

    Science.gov (United States)

    Grobe, Justin L

    2017-01-01

    Increasing evidence supports a major role for the renin-angiotensin system (RAS) in energy balance physiology. The RAS exists as a circulating system but also as a local paracrine/autocrine signaling mechanism in target tissues including the gastrointestinal tract, the brain, the kidney, and distinct adipose beds. Through activation of various receptors in these target tissues, the RAS contributes to the control of food intake behavior, digestive efficiency, spontaneous physical activity, and aerobic and anaerobic resting metabolism. Although the assortment of methodologies available to assess the various aspects of energy balance can be daunting for an investigator new to this area, a relatively straightforward array of entry-level and advanced methodologies can be employed to comprehensively and quantitatively dissect the effects of experimental manipulations on energy homeostasis. Such methodologies and a simple initial workflow for the use of these methods are described in this chapter, including the use of metabolic caging systems, bomb calorimetry, body composition analyzers, respirometry systems, and direct calorimetry systems. Finally, a brief discussion of the statistical analyses of metabolic data is included.

  5. Lessons Learned from Net Zero Energy Assessments and Renewable Energy Projects at Military Installations

    Energy Technology Data Exchange (ETDEWEB)

    Callahan, M.; Anderson, K.; Booth, S.; Katz, J.; Tetreault, T.

    2011-09-01

    Report highlights the increase in resources, project speed, and scale that is required to achieve the U.S. Department of Defense (DoD) energy efficiency and renewable energy goals and summarizes the net zero energy installation assessment (NZEI) process and the lessons learned from NZEI assessments and large-scale renewable energy projects implementations at DoD installations.

  6. A Petri Net model for distributed energy system

    Science.gov (United States)

    Konopko, Joanna

    2015-12-01

    Electrical networks need to evolve to become more intelligent, more flexible and less costly. The smart grid is the next generation power energy, uses two-way flows of electricity and information to create a distributed automated energy delivery network. Building a comprehensive smart grid is a challenge for system protection, optimization and energy efficient. Proper modeling and analysis is needed to build an extensive distributed energy system and intelligent electricity infrastructure. In this paper, the whole model of smart grid have been proposed using Generalized Stochastic Petri Nets (GSPN). The simulation of created model is also explored. The simulation of the model has allowed the analysis of how close the behavior of the model is to the usage of the real smart grid.

  7. A Petri Net model for distributed energy system

    Energy Technology Data Exchange (ETDEWEB)

    Konopko, Joanna [Warsaw University of Technology, The Faculty of Electronics and Information Technology, Institute of Computer Science, Nowowiejska Street 15/19, Warsaw 00-665 (Poland)

    2015-12-31

    Electrical networks need to evolve to become more intelligent, more flexible and less costly. The smart grid is the next generation power energy, uses two-way flows of electricity and information to create a distributed automated energy delivery network. Building a comprehensive smart grid is a challenge for system protection, optimization and energy efficient. Proper modeling and analysis is needed to build an extensive distributed energy system and intelligent electricity infrastructure. In this paper, the whole model of smart grid have been proposed using Generalized Stochastic Petri Nets (GSPN). The simulation of created model is also explored. The simulation of the model has allowed the analysis of how close the behavior of the model is to the usage of the real smart grid.

  8. Impact of the diet on net endogenous acid production and acid-base balance.

    Science.gov (United States)

    Poupin, Nathalie; Calvez, Juliane; Lassale, Camille; Chesneau, Caroline; Tomé, Daniel

    2012-06-01

    Net acid production, which is composed of volatile acids (15,000 mEq/day) and metabolic acids (70-100 mEq/day) is relatively small compared to whole-body H⁺ turnover (150,000 mEq/day). Metabolic acids are ingested from the diet or produced as intermediary or end products of endogenous metabolism. The three commonly reported sources of net acid production are the metabolism of sulphur amino acids, the metabolism or ingestion of organic acids, and the metabolism of phosphate esters or dietary phosphoproteins. Net base production occurs mainly as a result of absorption of organic anions from the diet. To maintain acid-base balance, ingested and endogenously produced acids are neutralized within the body by buffer systems or eliminated from the body through the respiratory (excretion of volatile acid in the form of CO₂) and urinary (excretion of fixed acids and remaining H⁺) pathways. Because of the many reactions involved in the acid-base balance, the direct determination of acid production is complex and is usually estimated through direct or indirect measurements of acid excretion. However, indirect approaches, which assess the acid-forming potential of the ingested diet based on its composition, do not take all the acid-producing reactions into account. Direct measurements therefore seem more reliable. Nevertheless, acid excretion does not truly provide information on the way acidity is dealt with in the plasma and this measurement should be interpreted with caution when assessing acid-base imbalance. Copyright © 2012 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.

  9. High-Intensity Sweeteners and Energy Balance

    Science.gov (United States)

    Swithers, Susan E.; Martin, Ashley A.; Davidson, Terry L.

    2010-01-01

    Recent epidemiological evidence points to a link between a variety of negative health outcomes (e.g. metabolic syndrome, diabetes and cardiovascular disease) and the consumption of both calorically sweetened beverages and beverages sweetened with high-intensity, non-caloric sweeteners. Research on the possibility that non-nutritive sweeteners promote food intake, body weight gain, and metabolic disorders has been hindered by the lack of a physiologically-relevant model that describes the mechanistic basis for these outcomes. We have suggested that based on Pavlovian conditioning principles, consumption of non-nutritive sweeteners could result in sweet tastes no longer serving as consistent predictors of nutritive postingestive consequences. This dissociation between the sweet taste cues and the caloric consequences could lead to a decrease in the ability of sweet tastes to evoke physiological responses that serve to regulate energy balance. Using a rodent model, we have found that intake of foods or fluids containing non-nutritive sweeteners was accompanied by increased food intake, body weight gain, accumulation of body fat, and weaker caloric compensation, compared to consumption of foods and fluids containing glucose. Our research also provided evidence consistent with the hypothesis that these effects of consuming saccharin may be associated with a decrement in the ability of sweet taste to evoke thermic responses, and perhaps other physiological, cephalic phase, reflexes that are thought to help maintain energy balance. PMID:20060008

  10. Carbon balance and energy fluxes of a Mediterranean crop

    Directory of Open Access Journals (Sweden)

    Simona Consoli

    2013-09-01

    Full Text Available This paper is based on the analysis of a long-term mass (carbon dioxide, water vapour and energy (solar radiation balance monitoring programme carried out during years 2010 and 2012 in an irrigated orange orchard in Sicily, using the Eddy Covariance (EC method. Orange (Citrus sinensis L. is one of the main fruit crops worldwide and its evergreen orchard may have a great potential for carbon sequestration, but few data are currently available. In the study, the role of the orchard system in sequestering atmospheric CO2 was analyzed, thus contributing to assess the carbon balance of the specie in the specific environment.Vertical energy fluxes of net radiation, soil heat, sensible heat and latent heat fluxes were measured at orchard scale by EC. Evapotranspiration (ET values were compared with upscaled transpiration data determined by the sap flow heat pulse technique, evidencing the degree of correspondence between instantaneous transpirational flux at tree level and the micrometeorological measurement of ET at orchard level.

  11. Multi-year net ecosystem carbon balance at a horticulture-extracted restored peatland

    Science.gov (United States)

    Nugent, Kelly; Strachan, Ian; Strack, Maria

    2017-04-01

    small source of CO2, NEE in the Typha plots showed significantly greater CO2 uptake capacity relative to any other restored plant community. High productivity combined with reduced CH4 flux suggests that Typha may be playing a key role in reducing the overall impact of the remnant ditches on the net ecosystem carbon balance. A preliminary footprint analysis suggests that ecosystem-level CH4 flux is being primarily driven by release from hotspots while the majority of the tower source area is a very small source of methane.

  12. Leptin signaling, adiposity, and energy balance.

    Science.gov (United States)

    Jéquier, Eric

    2002-06-01

    A chronic minor imbalance between energy intake and energy expenditure may lead to obesity. Both lean and obese subjects eventually reach energy balance and their body weight regulation implies that the adipose tissue mass is "sensed", leading to appropriate responses of energy intake and energy expenditure. The cloning of the ob gene and the identification of its encoded protein, leptin, have provided a system signaling the amount of adipose energy stores to the brain. Leptin, a hormone secreted by fat cells, acts in rodents via hypothalamic receptors to inhibit feeding and increase thermogenesis. A feedback regulatory loop with three distinct steps has been identified: (1) a sensor (leptin production by adipose cells) monitors the size of the adipose tissue mass; (2) hypothalamic centers receive and integrate the intensity of the leptin signal through leptin receptors (LRb); (3) effector systems, including the sympathetic nervous system, control the two main determinants of energy balance-energy intake and energy expenditure. While this feedback regulatory loop is well established in rodents, there are many unsolved questions about its applicability to body weight regulation in humans. The rate of leptin production is related to adiposity, but a large portion of the interindividual variability in plasma leptin concentration is independent of body fatness. Gender is an important factor determining plasma leptin, with women having markedly higher leptin concentrations than men for any given degree of fat mass. The ob mRNA expression is also upregulated by glucocorticoids, whereas stimulation of the sympathetic nervous system results in its inhibition. Furthermore, leptin is not a satiety factor in humans because changes in food intake do not induce short-term increases in plasma leptin levels. After its binding to LRb in the hypothalamus, leptin stimulates a specific signaling cascade that results in the inhibition of several orexigenic neuropeptides, while

  13. Evaluation of satellite and reanalysis-based global net surface energy flux and uncertainty estimates

    Science.gov (United States)

    Allan, Richard; Liu, Chunlei

    2017-04-01

    The net surface energy flux is central to the climate system yet observational limitations lead to substantial uncertainty (Trenberth and Fasullo, 2013; Roberts et al., 2016). A combination of satellite-derived radiative fluxes at the top of atmosphere (TOA) adjusted using the latest estimation of the net heat uptake of the Earth system, and the atmospheric energy tendencies and transports from the ERA-Interim reanalysis are used to estimate surface energy flux globally (Liu et al., 2015). Land surface fluxes are adjusted through a simple energy balance approach using relations at each grid point with the consideration of snowmelt to improve regional realism. The energy adjustment is redistributed over the oceans using a weighting function to avoid meridional discontinuities. Uncertainties in surface fluxes are investigated using a variety of approaches including comparison with a range of atmospheric reanalysis input data and products. Zonal multiannual mean surface flux uncertainty is estimated to be less than 5 Wm-2 but much larger uncertainty is likely for regional monthly values. The meridional energy transport is calculated using the net surface heat fluxes estimated in this study and the result shows better agreement with observations in Atlantic than before. The derived turbulent fluxes (difference between the net heat flux and the CERES EBAF radiative flux at surface) also have good agreement with those from OAFLUX dataset and buoy observations. Decadal changes in the global energy budget and the hemisphere energy imbalances are quantified and present day cross-equator heat transports is re-evaluated as 0.22±0.15 PW southward by the atmosphere and 0.32±0.16 PW northward by the ocean considering the observed ocean heat sinks (Roemmich et al., 2006) . Liu et al. (2015) Combining satellite observations and reanalysis energy transports to estimate global net surface energy fluxes 1985-2012. J. Geophys. Res., Atmospheres. ISSN 2169-8996 doi: 10.1002/2015JD

  14. Development of net energy ratio for quad-generation pathways

    DEFF Research Database (Denmark)

    Rudra, Souman; Rosendahl, Lasse; Kumar, Amit

    2012-01-01

    The conversion of biomass to four different outputs via gasification and catalytic methanation is a renewable technology that could reduce the use of fossil fuels and GHG emissions. This study investigates the energy aspects of producing electricity, heat, methanol and methane. The Gas Technology......-based power, heat, methanol and methane production pathway using GTI technology. Since more efficient alternatives exist for the generation of heat and electricity from biomass, it is argued that syngas is best used for methanol production. The aim of this study was to evaluate the energy performance...... Institute (GTI) gasifier and Circulating Fluidized Bed (CFB) technologies are used for this quad generation process. Three different biomass feedstocks are considered in this study. The net energy ratio for six different pathways having the range of between 1.3–9.3. The lowest limit corresponds to the straw...

  15. Intelligent Controls for Net-Zero Energy Buildings

    Energy Technology Data Exchange (ETDEWEB)

    Li, Haorong; Cho, Yong; Peng, Dongming

    2011-10-30

    The goal of this project is to develop and demonstrate enabling technologies that can empower homeowners to convert their homes into net-zero energy buildings in a cost-effective manner. The project objectives and expected outcomes are as follows: • To develop rapid and scalable building information collection and modeling technologies that can obtain and process “as-built” building information in an automated or semiautomated manner. • To identify low-cost measurements and develop low-cost virtual sensors that can monitor building operations in a plug-n-play and low-cost manner. • To integrate and demonstrate low-cost building information modeling (BIM) technologies. • To develop decision support tools which can empower building owners to perform energy auditing and retrofit analysis. • To develop and demonstrate low-cost automated diagnostics and optimal control technologies which can improve building energy efficiency in a continual manner.

  16. The global land and ocean mean energy balance

    Science.gov (United States)

    Wild, Martin; Folini, Doris

    2016-04-01

    The energy balance over land and oceans governs a diversity of terrestrial and maritime processes and is the key determinant of climatic conditions in these areas. Despite its crucial role, climate models show significant differences in the individual components of the energy balance over both land and oceans, particularly at the surface. Here we combine a comprehensive set of radiation observations from GEBA and BSRN with 43 state-of-the-art climate models to infer best estimates for present day annual mean downward solar and thermal radiation averaged over land and ocean surfaces, together with their uncertainty ranges. Over land (including the polar ice sheets), where most direct observations are available to constrain the surface fluxes, we obtain 184 and 306 Wm-2 for solar and thermal downward radiation, respectively. Over oceans, with weaker observational constraints, corresponding estimates are around 185 and 356 Wm-2. These values closely agree, mostly within 3 Wm-2, with the respective quantities independently derived by a state-of-the-art reanalysis (ERA-Interim) and satellite-derived product (surface CERES EBAF). This remarkable consistency enhances confidence in the determined flux magnitudes, which so far stated large uncertainty sources in the energy budgets. The estimated downward solar radiation averaged over land and ocean surfaces is almost identical despite differences in the incoming solar flux at the Top-of-Atmosphere (TOA) around 20 Wm-2, indicative of an overall less transparent atmosphere over oceans than land. Considering additionally surface albedo and emissivity, we infer a surface absorbed solar and net thermal radiation of 136 and -66 Wm-2 over land, and 170 and -53 Wm-2 over oceans, respectively. The surface net radiation is thus estimated at 70 Wm-2 over land and 117 Wm-2 over oceans, which may impose additional constraints on the poorly known sensible and latent heat flux magnitudes. These are estimated here near 32 and 38 Wm-2 over

  17. Surface energy balance measurements in the Mexico City: a review

    Energy Technology Data Exchange (ETDEWEB)

    Tejeda Martinez, A. [Universidad Veracruzana, Xalapa, Veracruz (Mexico); Jauregui Ostos, E. [Centro de Ciencias de la Atmosfera, Universidad Nacional Autonoma de Mexico, UNAM, Mexico, D.F. (Mexico)

    2005-01-01

    During the last decade of the 20th Century, diverse campaigns for measuring the atmospheric energy balance were performed in downtown Mexico City (School of Mines and Preparatory School No. 7), in the southern suburbs (University Reserve) and in the surrounding rural areas (Plan Texcoco), in addition to a campaign carried out in 1985 in the Tacubaya district, a suburban western peripheral site. The objective was to obtain data for a better understanding of the climatic alterations due to urbanization, particularly to describe the role that the modification of the natural ground cover has played as a result of paving and the construction of urban canyons. In this paper, a review of these campaigns is presented. Energy partitioning in some areas (Tacubaya and Preparatory School No.7) is similar to that observed in urban centers of middle latitudes, whereas the major contrast was observed between Texcoco, with maximum energy consumption through evaporation, and School of Mines, where the latent heat is as low as in a desert. From the values of the correlations among the different components of energy balance, it may be possible to attempt the modeling of the diverse components of energy balance by means of regression equations starting from the net radiation. Those same coefficients distinguish the type of environment: urban, suburban or rural. [Spanish] Las primeras mediciones de balance energetico en la Ciudad de Mexico se realizaron en 1985 en un suburbio al poniente de la ciudad (el observatorio de Tacubaya). Ya en la decada de los anos noventa del siglo XX, dichas observaciones se multiplicaron tanto en el centro historico (antigua Escuela de Minas y en el edificio de la Preparatoria No. 7), como en otros sitios al sur (en terrenos de Ciudad Universitaria) y en la periferia rural (Plan Texcoco). El proposito de estas mediciones ha sido tener un mejor entendimiento de las alteraciones climaticas debidas a la urbanizacion. En este trabajo se presenta una revision

  18. NET-ZERO ENERGY BUILDING OPERATOR TRAINING PROGRAM (NZEBOT)

    Energy Technology Data Exchange (ETDEWEB)

    Brizendine, Anthony; Byars, Nan; Sleiti, Ahmad; Gehrig, Bruce; Lu, Na

    2012-12-31

    The primary objective of the Net-Zero Energy Building Operator Training Program (NZEBOT) was to develop certificate level training programs for commercial building owners, managers and operators, principally in the areas of energy / sustainability management. The expected outcome of the project was a multi-faceted mechanism for developing the skill-based competency of building operators, owners, architects/engineers, construction professionals, tenants, brokers and other interested groups in energy efficient building technologies and best practices. The training program draws heavily on DOE supported and developed materials available in the existing literature, as well as existing, modified, and newly developed curricula from the Department of Engineering Technology & Construction Management (ETCM) at the University of North Carolina at Charlotte (UNC-Charlotte). The project goal is to develop a certificate level training curriculum for commercial energy and sustainability managers and building operators that: 1) Increases the skill-based competency of building professionals in energy efficient building technologies and best practices, and 2) Increases the workforce pool of expertise in energy management and conservation techniques. The curriculum developed in this project can subsequently be used to establish a sustainable energy training program that can contribute to the creation of new “green” job opportunities in North Carolina and throughout the Southeast region, and workforce training that leads to overall reductions in commercial building energy consumption. Three energy training / education programs were developed to achieve the stated goal, namely: 1. Building Energy/Sustainability Management (BESM) Certificate Program for Building Managers and Operators (40 hours); 2. Energy Efficient Building Technologies (EEBT) Certificate Program (16 hours); and 3. Energy Efficent Buildings (EEB) Seminar (4 hours). Training Program 1 incorporates the following

  19. Energy Balance Models and Planetary Dynamics

    Science.gov (United States)

    Domagal-Goldman, Shawn

    2012-01-01

    We know that planetary dynamics can have a significant affect on the climate of planets. Planetary dynamics dominate the glacial-interglacial periods on Earth, leaving a significant imprint on the geological record. They have also been demonstrated to have a driving influence on the climates of other planets in our solar system. We should therefore expect th.ere to be similar relationships on extrasolar planets. Here we describe a simple energy balance model that can predict the growth and thickness of glaciers, and their feedbacks on climate. We will also describe model changes that we have made to include planetary dynamics effects. This is the model we will use at the start of our collaboration to handle the influence of dynamics on climate.

  20. Simulated Net Ecosystem Carbon Balance of Western US Forests Under Contemporary Climate and Management

    Science.gov (United States)

    Yang, Z.; Law, B. E.; Jones, M. O.

    2015-12-01

    Previous projections of the contemporary forest carbon balance in the western US showed uncertainties associated with impacts of climate extremes and a coarse spatio-temporal resolution implemented over heterogeneous mountain regions. We modified the Community Land Model (CLM) 4.5 to produce 4km resolution forest carbon changes with drought, fire and management in the western US. We parameterized the model with species data using local plant trait observations for 30 species. To quantify uncertainty, we evaluated the model with data from flux sites, inventories and ancillary data in the region. Simulated GPP was lower than the measurements at our AmeriFlux sites by 17-22%. Simulated burned area was generally higher than Landsat observations, suggesting the model overestimates fire emissions with the new fire model. Landsat MTBS data show high severity fire represents only a small portion of the total burnt area (12-14%), and no increasing trend from 1984 to 2011. Moderate severity fire increased ~0.23%/year due to fires in the Sierra Nevada (Law & Waring 2014). Oregon, California, and Washington were a net carbon sink, and net ecosystem carbon balance (NECB) declined in California over the past 15 years, partly due to drought impacts. Fire emissions were a small portion of the regional carbon budget compared with the effect of harvest removals. Fossil fuel emissions in CA are more than 3x that of OR and WA combined, but are lower per capita. We also identified forest regions that are most vulnerable to climate-driven transformations and to evaluate the effects of management strategies on forest NECB. Differences in forest NECB among states are strongly influenced by the extent of drought (drier longer in the SW) and management intensity (higher in the PNW).

  1. Brazilian energy balance 1999: 1983 to 1998 period

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-07-01

    This report shows the energy flows of different primary and secondary sources, from the production to the final consumption in every sector of the Brazilian economy, for the 1983 to 1998 period. It is divided into nine chapters, as follows: summary; energy supply and consumption by source; energy consumption by sector; energy import and export; transformation centers balances; energy resources and reserves; energy and socio economy; energy data relating to brazilian states; and appendices - installed capacity, world data, general structure of the balance, information processing, conversion units and consolidated energy balance.

  2. Net ecosystem exchange of CO2 and carbon balance for eight temperate organic soils under agricultural management

    DEFF Research Database (Denmark)

    Elsgaard, Lars; Görres, C.-M.; Hoffmann, Carl Christian

    2012-01-01

    This study presents the first annual estimates of net ecosystem exchange (NEE) of CO2 and net ecosystem carbon balances (NECB) of contrasting Danish agricultural peatlands. Studies were done at eight sites representing permanent grasslands (PG) and rotational (RT) arable soils cropped to barley......) sites, NEE (mean ± standard error, SE) was 5.1 ± 0.9 and 8.6 ± 2.0 Mg C ha−1 yr−1, respectively, but with the overall lowest value observed for potato cropping (3.5 Mg C ha−1 yr−1). This was partly attributed to a short-duration vegetation period and drying of the soil especially in potato ridges. NECB...... and temperate climate zones. It was stressed that evaluation of emission factors should explicitly differentiate between data representing net C balance from a soil perspective and CO2-C balance from an atmospheric perspective. Modelling of inter-annual variability in NEE for three selected sites during a 21...

  3. The surface energy balance of a polygonal tundra site in northern Siberia – Part 2: Winter

    Directory of Open Access Journals (Sweden)

    J. Boike

    2011-06-01

    Full Text Available In this study, we present the winter time surface energy balance at a polygonal tundra site in northern Siberia based on independent measurements of the net radiation, the sensible heat flux and the ground heat flux from two winter seasons. The latent heat flux is inferred from measurements of the atmospheric turbulence characteristics and a model approach. The long-wave radiation is found to be the dominant factor in the surface energy balance. The radiative losses are balanced to about 60 % by the ground heat flux and almost 40 % by the sensible heat fluxes, whereas the contribution of the latent heat flux is small. The main controlling factors of the surface energy budget are the snow cover, the cloudiness and the soil temperature gradient. Large spatial differences in the surface energy balance are observed between tundra soils and a small pond. The ground heat flux released at a freezing pond is by a factor of two higher compared to the freezing soil, whereas large differences in net radiation between the pond and soil are only observed at the end of the winter period. Differences in the surface energy balance between the two winter seasons are found to be related to differences in snow depth and cloud cover which strongly affect the temperature evolution and the freeze-up at the investigated pond.

  4. A Net Energy-based Analysis for a Climate-constrained Sustainable Energy Transition

    CERN Document Server

    Sgouridis, Sgouris; Csala, Denes

    2015-01-01

    The transition from a fossil-based energy economy to one based on renewable energy is driven by the double challenge of climate change and resource depletion. Building a renewable energy infrastructure requires an upfront energy investment that subtracts from the net energy available to society. This investment is determined by the need to transition to renewable energy fast enough to stave off the worst consequences of climate change and, at the same time, maintain a sufficient net energy flow to sustain the world's economy and population. We show that a feasible transition pathway requires that the rate of investment in renewable energy should accelerate approximately by an order of magnitude if we are to stay within the range of IPCC recommendations.

  5. Controls on declining carbon balance with leaf age among 10 woody species in Australian woodland: do leaves have zero daily net carbon balances when they die?

    Science.gov (United States)

    Reich, Peter B; Falster, Daniel S; Ellsworth, David S; Wright, Ian J; Westoby, Mark; Oleksyn, Jacek; Lee, Tali D

    2009-01-01

    * Here, we evaluated how increased shading and declining net photosynthetic capacity regulate the decline in net carbon balance with increasing leaf age for 10 Australian woodland species. We also asked whether leaves at the age of their mean life-span have carbon balances that are positive, zero or negative. * The net carbon balances of 2307 leaves on 53 branches of the 10 species were estimated. We assessed three-dimensional architecture, canopy openness, photosynthetic light response functions and dark respiration rate across leaf age sequences on all branches. We used YPLANT to estimate light interception and to model carbon balance along the leaf age sequences. * As leaf age increased to the mean life-span, increasing shading and declining photosynthetic capacity each separately reduced daytime carbon gain by approximately 39% on average across species. Together, they reduced daytime carbon gain by 64% on average across species. * At the age of their mean life-span, almost all leaves had positive daytime carbon balances. These per leaf carbon surpluses were of a similar magnitude to the estimated whole-plant respiratory costs per leaf. Thus, the results suggest that a whole-plant economic framework, including respiratory costs, may be useful in assessing controls on leaf longevity.

  6. Net energy production and emissions mitigation of domestic wastewater treatment system: a comparison of different biogas-sludge use alternatives.

    Science.gov (United States)

    Chen, Shaoqing; Chen, Bin

    2013-09-01

    Wastewater treatment systems are increasingly designed for the recovery of valuable chemicals and energy in addition to waste stream disposal. Herein, the life-cycle energy production and emissions mitigation of a typical domestic wastewater treatment system were assessed, in which different combinations of biogas use and sludge processing lines for industrial or household applications were considered. The results suggested that the reuse of biogas and sludge was so important in the system's overall energy balance and environmental performance that it may offset the cost in the plant's installation and operation. Combined heat and power and household utilization were two prior options for net energy production, provided an ideal power conversion efficiency and biogas production. The joint application of household biogas use and sludge nutrient processing achieved both high net energy production and significant environmental remediation across all impact categories, representing the optimal tradeoff for domestic wastewater treatment. Copyright © 2013 Elsevier Ltd. All rights reserved.

  7. Brazilian energy balance 1996: 1980 to 1995 period

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-12-31

    This report shows the energy flows of different primary and secondary sources, from the production to the final consumption in every sector of the Brazilian economy, for the 1980 to 1995 period. It`s divided into nine chapters, as follows: summary; energy supply and consumption by source; energy import and export; transformation centers balances; energy sources and reserves; energy and socio economy; regional parameters; and appendices - installed capacity, international data, general structure of the balance, information processing, conversion units and consolidated energy balances 1 fig., 68 graphs., 145 tabs.

  8. Measured Zero Net Energy Performance: Results, Lessons, and Surprises

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Carrie; LaRue, Anna; Pigman, Margaret; Roberts, Jon; Kaneda, David; Connelly, Dylan; Elliott, John; Pless, Shanti; Pande, Abhijeet; Dean, Edward; Anbarlilar, Can

    2016-08-26

    As more and more zero net energy (ZNE) buildings are built and monitored, we can learn from both careful case studies of individual projects as well as a broader perspective of trends over time. In a forum sponsored by Pacific Gas and Electric Company (PG&E), eight expert speakers discussed: results and lessons from monitoring occupied ZNE buildings; best practices for setting performance targets and getting actionable performance information, and; things that have surprised them about monitored ZNE buildings. This paper distills the content of the forum by laying out the most common hurdles that are encountered in setting up monitoring projects, frequent performance issues that the monitoring uncovers, and lessons learned that can be applied to future projects.

  9. The energy balance of utilising meadow grass in Danish biogas production

    DEFF Research Database (Denmark)

    Meyer, Ane Katharina Paarup; Raju, Chitra Sangaraju; Kucheryavskiy, Sergey V.

    2015-01-01

    of meadow areas, different relevant geo-datasets, spatial analyses, and various statistical analyses. The results show that values for the energy return on energy invested (EROEI) ranging from 1.7 to 3.3 can be obtained when utilising meadow grasses in local biogas production. The total national net energy......This paper presents a study of the energy balance of utilising nature conservation biomass from meadow habitats in Danish biogas production. Utilisation of nature conservation grass in biogas production in Denmark represents an interesting perspective for enhancing nature conservation of the open...

  10. A reliable energy-efficient multi-level routing algorithm for wireless sensor networks using fuzzy Petri nets.

    Science.gov (United States)

    Yu, Zhenhua; Fu, Xiao; Cai, Yuanli; Vuran, Mehmet C

    2011-01-01

    A reliable energy-efficient multi-level routing algorithm in wireless sensor networks is proposed. The proposed algorithm considers the residual energy, number of the neighbors and centrality of each node for cluster formation, which is critical for well-balanced energy dissipation of the network. In the algorithm, a knowledge-based inference approach using fuzzy Petri nets is employed to select cluster heads, and then the fuzzy reasoning mechanism is used to compute the degree of reliability in the route sprouting tree from cluster heads to the base station. Finally, the most reliable route among the cluster heads can be constructed. The algorithm not only balances the energy load of each node but also provides global reliability for the whole network. Simulation results demonstrate that the proposed algorithm effectively prolongs the network lifetime and reduces the energy consumption.

  11. Cognitive determinants of energy balance-related behaviours : measurement issues

    NARCIS (Netherlands)

    Kremers, Stef P J; Visscher, Tommy L S; Seidell, Jacob C; van Mechelen, Willem; Brug, Johannes

    2005-01-01

    The burden of disease as a result of overweight and obesity calls for in-depth examination of the main causes of behavioural actions responsible for weight gain. Since weight gain is the result of a positive energy balance, these behavioural actions are referred to as 'energy balance-related

  12. Stomach regulates energy balance via acylated ghrelin and desacyl ghrelin

    OpenAIRE

    Asakawa, A; Inui, A; Fujimiya, M; Sakamaki, R; Shinfuku, N; Ueta, Y; Meguid, M M; Kasuga, M

    2005-01-01

    Background/Aims: The gastric peptide ghrelin, an endogenous ligand for growth-hormone secretagogue receptor, has two major molecular forms: acylated ghrelin and desacyl ghrelin. Acylated ghrelin induces a positive energy balance, while desacyl ghrelin has been reported to be devoid of any endocrine activities. The authors examined the effects of desacyl ghrelin on energy balance.

  13. Energy Balance: An Overview With Emphasis on Children

    OpenAIRE

    Tam, Charmaine S; Ravussin, Eric

    2011-01-01

    Childhood obesity is a significant public health problem, affecting one in five children in the United States. At the crux of this issue is a dysregulation of energy intake and energy expenditure. This review will provide an overview on energy and nutrient balance. We discuss energy balance studies in children using indirect and direct measures, and focus particularly on obesity as a deleterious consequence in childhood survivors of cancer. Obesity affects 11–57% of children with acute lympho...

  14. System analysis of a bio-energy plantation: full greenhouse gas balance and energy accounting (POPFULL)

    Science.gov (United States)

    Ceulemans, R.; Janssens, I.; Berhongaray, G.; Broeckx, L.; De Groote, T.; ElKasmioui, O.; Fichot, R.; Njakou Djomo, S.; Verlinden, M.; Zona, D.

    2011-12-01

    In recent year the environmental impact of fossil fuels and their reduced availability are leading to an increasing interest in renewable energy sources, among them bio-energy. However, the cost/benefit in establishing, managing, and using these plantations for energy production should be quantified together with their environmental impact. In this project we are performing a full life cycle analysis (LCA) balance of the most important greenhouse gases (CO2, CH4, N2O, H2O and O3), together with full energy accounting of a short-rotation coppice (SRC) plantation with fast-growing trees. We established the plantation two years ago and we have been monitoring net fluxes of CO2, N2O, CH4, and O3, in combination with biomass pools (incl. soil) and fluxes, and volatile organic carbon (VOCs). This poplar plantation will be monitored for another two years then harvested and transformed into bio-energy. For the energy accounting we are performing a life cycle analysis and energy efficiency assessments over the entire cycle of the plantation until the production of electricity and heat. Here we present an overview of the results from the first two years from the plantation establishment, and some of the projections based on these first results.

  15. Energy balance of biofuel production from biological conversion of crude glycerol.

    Science.gov (United States)

    Zhang, Xiaolei; Yan, Song; Tyagi, Rajeshwar D; Surampalli, Rao Y; Valéro, Jose R

    2016-04-01

    Crude glycerol, a by-product of biodiesel production, has gained significant attention as a carbon source for biofuel production. This study evaluated the energy balance of biodiesel, hydrogen, biogas, and ethanol production from 3.48 million L of crude glycerol (80% w/v). The conversion efficiency (energy output divided by energy invested) was 1.16, 0.22, 0.27, and 0.40 for the production of biodiesel, hydrogen, biogas, and ethanol respectively. It was found that the use of crude glycerol for biodiesel production was an energy gain process, with a positive energy balance and conversion efficiency of greater than 1. The energy balance revealed a net energy gain of 5226 GJ per 1 million kg biodiesel produced. Production of hydrogen, biogas and ethanol from crude glycerol were energy loss processes. Therefore, the conversion of crude glycerol to lipids and subsequently to biodiesel is suggested to be a better option compared to hydrogen, biogas, or ethanol production with respect to energy balance. Copyright © 2016. Published by Elsevier Ltd.

  16. Comparison of four different energy balance models for estimating evapotranspiration in the Midwestern United States

    Science.gov (United States)

    Singh, Ramesh K.; Senay, Gabriel B.

    2016-01-01

    The development of different energy balance models has allowed users to choose a model based on its suitability in a region. We compared four commonly used models—Mapping EvapoTranspiration at high Resolution with Internalized Calibration (METRIC) model, Surface Energy Balance Algorithm for Land (SEBAL) model, Surface Energy Balance System (SEBS) model, and the Operational Simplified Surface Energy Balance (SSEBop) model—using Landsat images to estimate evapotranspiration (ET) in the Midwestern United States. Our models validation using three AmeriFlux cropland sites at Mead, Nebraska, showed that all four models captured the spatial and temporal variation of ET reasonably well with an R2 of more than 0.81. Both the METRIC and SSEBop models showed a low root mean square error (0.80), whereas the SEBAL and SEBS models resulted in relatively higher bias for estimating daily ET. The empirical equation of daily average net radiation used in the SEBAL and SEBS models for upscaling instantaneous ET to daily ET resulted in underestimation of daily ET, particularly when the daily average net radiation was more than 100 W·m−2. Estimated daily ET for both cropland and grassland had some degree of linearity with METRIC, SEBAL, and SEBS, but linearity was stronger for evaporative fraction. Thus, these ET models have strengths and limitations for applications in water resource management.

  17. Comparison of Four Different Energy Balance Models for Estimating Evapotranspiration in the Midwestern United States

    Directory of Open Access Journals (Sweden)

    Ramesh K. Singh

    2015-12-01

    Full Text Available The development of different energy balance models has allowed users to choose a model based on its suitability in a region. We compared four commonly used models—Mapping EvapoTranspiration at high Resolution with Internalized Calibration (METRIC model, Surface Energy Balance Algorithm for Land (SEBAL model, Surface Energy Balance System (SEBS model, and the Operational Simplified Surface Energy Balance (SSEBop model—using Landsat images to estimate evapotranspiration (ET in the Midwestern United States. Our models validation using three AmeriFlux cropland sites at Mead, Nebraska, showed that all four models captured the spatial and temporal variation of ET reasonably well with an R2 of more than 0.81. Both the METRIC and SSEBop models showed a low root mean square error (<0.93 mm·day−1 and a high Nash–Sutcliffe coefficient of efficiency (>0.80, whereas the SEBAL and SEBS models resulted in relatively higher bias for estimating daily ET. The empirical equation of daily average net radiation used in the SEBAL and SEBS models for upscaling instantaneous ET to daily ET resulted in underestimation of daily ET, particularly when the daily average net radiation was more than 100 W·m−2. Estimated daily ET for both cropland and grassland had some degree of linearity with METRIC, SEBAL, and SEBS, but linearity was stronger for evaporative fraction. Thus, these ET models have strengths and limitations for applications in water resource management.

  18. Dietary energy density, inflammation and energy balance in palliative care cancer patients.

    Science.gov (United States)

    Wallengren, Ola; Bosaeus, Ingvar; Lundholm, Kent

    2013-02-01

    Diet energy density is correlated with energy intake in patients with advanced cancer. Little information is available about the effects of energy density on energy balance, nor about the influence of other factors, such as systemic inflammation and disease stage. We assessed whether dietary energy density or energy intake predict energy balance over 4 months in patients with advanced cancer. We examined also the influence of systemic inflammation and survival time. Energy balance was calculated from the change in body energy content by repeated dual-energy X-ray scans in 107 patients for a total of 164 4-month measurement periods. A linear mixed model was used to investigate relationships between diet energy density (kcal/g), energy intake (kcal/day) and energy balance with systemic inflammation and survival as covariates. In an unadjusted model, the energy density of solid food and energy intake were positive predictors of energy balance (P energy density and energy intake increased energy balance by 38 and 41 kcal/day, respectively. The total diet energy density did not predict energy balance (P > 0.05). Survival was positively (P energy balance. Only energy intake remained a significant predictor of energy balance after adjustment for survival and inflammatory status. Dietary energy density is positively associated with energy balance in patients with advanced cancer. Relations between energy intake, energy density and energy balance are affected by systemic inflammation. Thus, targeting systemic inflammation may be important in nutritional interventions in this patient group. Copyright © 2012 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.

  19. Targeting Net Zero Energy at Marine Corps Base Kaneohe Bay, Hawaii: Assessment and Recommendations

    Energy Technology Data Exchange (ETDEWEB)

    Burman, K.; Kandt, A.; Lisell, L.; Booth, S.; Walker, A.; Roberts, J.; Falcey, J.

    2011-11-01

    DOD's U.S. Pacific Command has partnered with the U.S. Department of Energy's (DOE) National Renewable Energy Laboratory (NREL) to assess opportunities for increasing energy security through renewable energy and energy efficiency in Hawaii installations. NREL selected Marine Corps Base Hawaii (MCBH), Kaneohe Bay to receive technical support for net zero energy assessment and planning funded through the Hawaii Clean Energy Initiative (HCEI). NREL performed a comprehensive assessment to appraise the potential of MCBH Kaneohe Bay to achieve net zero energy status through energy efficiency, renewable energy, and electric vehicle integration. This report summarizes the results of the assessment and provides energy recommendations.

  20. Effects of Permafrost Thaw on Net Ecosystem Carbon Balance in a Subarctic Peatland

    Science.gov (United States)

    Wang, Z.; Roulet, N. T.; Moore, T. R.

    2014-12-01

    This research is to assess changes in net ecosystem carbon balance (NECB) with permafrost thaw in northern peatland: in particular how changes in C biogeochemistry influence NECB. Thawed transects associated with varying stages of permafrost thaw: from palsas with intact permafrost (P), through edge of palsa (EP), dry lawn (DL), wet lawn (WL), edge of thawed pond (ET), pond sedges (PS), to several thawed ponds (TP) in a subarctic peatland in northern Quebec were sampled in the snow free seasons of 2013 and 2014. The exchange of CO2 and CH4, vegetation, dissolved organic C (DOC) concentration and biodegradability, active layer depth, air and peat temperatures, water table depth (WT), pH, and conductivity were measured. Peat temperatures were quite similar among different locations, but the WT decreased significantly along the transect creating varied environmental conditions that supporting different plant communities. From dry to wet area, vegetation abundance and biomass showed reductions of shrubs and lichens, and increases of Sphagnum, grasses and sedges. Pore water pH increased from dry to wet area, and conductivity slightly decreased. Wet thaw area WL, ET and PS had relatively higher season gross ecosystem production (GEP) and higher season ecosystem respiration (ER), but relative similar net ecosystem CO2 exchange (NEE). Only TP had a significant higher positive season NEE. Palsa was the only CH4 sink, and quite high CH4 emissions were found after it thawed. CH4-C release significantly increased from dry to wet in thawed area, which even several times bigger than total C exchange in ET and PS. Generally, wet area had higher DOC concentration and higher DOC biodegradability indicated by lower SUVA254 (except PS which received great influence from pond). All components in the NECB (GEP, ER, CH4, DOC) increased significantly in magnitude from palsa to wet thawed area, and ecosystem C sink turned into source as palsa thawed into PS and TP. These results

  1. Aquifer Thermal Energy Storage for Seasonal Thermal Energy Balance

    Science.gov (United States)

    Rostampour, Vahab; Bloemendal, Martin; Keviczky, Tamas

    2017-04-01

    Aquifer Thermal Energy Storage (ATES) systems allow storing large quantities of thermal energy in subsurface aquifers enabling significant energy savings and greenhouse gas reductions. This is achieved by injection and extraction of water into and from saturated underground aquifers, simultaneously. An ATES system consists of two wells and operates in a seasonal mode. One well is used for the storage of cold water, the other one for the storage of heat. In warm seasons, cold water is extracted from the cold well to provide cooling to a building. The temperature of the extracted cold water increases as it passes through the building climate control systems and then gets simultaneously, injected back into the warm well. This procedure is reversed during cold seasons where the flow direction is reversed such that the warmer water is extracted from the warm well to provide heating to a building. From the perspective of building climate comfort systems, an ATES system is considered as a seasonal storage system that can be a heat source or sink, or as a storage for thermal energy. This leads to an interesting and challenging optimal control problem of the building climate comfort system that can be used to develop a seasonal-based energy management strategy. In [1] we develop a control-oriented model to predict thermal energy balance in a building climate control system integrated with ATES. Such a model however cannot cope with off-nominal but realistic situations such as when the wells are completely depleted, or the start-up phase of newly installed wells, etc., leading to direct usage of aquifer ambient temperature. Building upon our previous work in [1], we here extend the mathematical model for ATES system to handle the above mentioned more realistic situations. Using our improved models, one can more precisely predict system behavior and apply optimal control strategies to manage the building climate comfort along with energy savings and greenhouse gas reductions

  2. Hypothalamic Inflammation and Energy Balance Disruptions: Spotlight on Chemokines

    OpenAIRE

    Le Thuc, Ophélia; Stobbe, Katharina; Cansell, Céline; Nahon, Jean-Louis; Blondeau, Nicolas; Rovère, Carole

    2017-01-01

    The hypothalamus is a key brain region in the regulation of energy balance as it controls food intake and both energy storage and expenditure through integration of humoral, neural, and nutrient-related signals and cues. Many years of research have focused on the regulation of energy balance by hypothalamic neurons, but the most recent findings suggest that neurons and glial cells, such as microglia and astrocytes, in the hypothalamus actually orchestrate together several metabolic functions....

  3. Serotonin and the regulation of mammalian energy balance.

    Science.gov (United States)

    Donovan, Michael H; Tecott, Laurence H

    2013-01-01

    Maintenance of energy balance requires regulation of the amount and timing of food intake. Decades of experiments utilizing pharmacological and later genetic manipulations have demonstrated the importance of serotonin signaling in this regulation. Much progress has been made in recent years in understanding how central nervous system (CNS) serotonin systems acting through a diverse array of serotonin receptors impact feeding behavior and metabolism. Particular attention has been paid to mechanisms through which serotonin impacts energy balance pathways within the hypothalamus. How upstream factors relevant to energy balance regulate the release of hypothalamic serotonin is less clear, but work addressing this issue is underway. Generally, investigation into the central serotonergic regulation of energy balance has had a predominantly "hypothalamocentric" focus, yet non-hypothalamic structures that have been implicated in energy balance regulation also receive serotonergic innervation and express multiple subtypes of serotonin receptors. Moreover, there is a growing appreciation of the diverse mechanisms through which peripheral serotonin impacts energy balance regulation. Clearly, the serotonergic regulation of energy balance is a field characterized by both rapid advances and by an extensive and diverse set of central and peripheral mechanisms yet to be delineated.

  4. Predicting Energy Performance of a Net-Zero Energy Building: A Statistical Approach

    Science.gov (United States)

    Kneifel, Joshua; Webb, David

    2016-01-01

    Performance-based building requirements have become more prevalent because it gives freedom in building design while still maintaining or exceeding the energy performance required by prescriptive-based requirements. In order to determine if building designs reach target energy efficiency improvements, it is necessary to estimate the energy performance of a building using predictive models and different weather conditions. Physics-based whole building energy simulation modeling is the most common approach. However, these physics-based models include underlying assumptions and require significant amounts of information in order to specify the input parameter values. An alternative approach to test the performance of a building is to develop a statistically derived predictive regression model using post-occupancy data that can accurately predict energy consumption and production based on a few common weather-based factors, thus requiring less information than simulation models. A regression model based on measured data should be able to predict energy performance of a building for a given day as long as the weather conditions are similar to those during the data collection time frame. This article uses data from the National Institute of Standards and Technology (NIST) Net-Zero Energy Residential Test Facility (NZERTF) to develop and validate a regression model to predict the energy performance of the NZERTF using two weather variables aggregated to the daily level, applies the model to estimate the energy performance of hypothetical NZERTFs located in different cities in the Mixed-Humid climate zone, and compares these estimates to the results from already existing EnergyPlus whole building energy simulations. This regression model exhibits agreement with EnergyPlus predictive trends in energy production and net consumption, but differs greatly in energy consumption. The model can be used as a framework for alternative and more complex models based on the

  5. Net energy output from harvesting small-diameter trees using a mechanized system

    Science.gov (United States)

    Fei Pan; Han-Sup Han; Leonard R. Johnson; William J. Elliot

    2008-01-01

    What amount of extra energy can be generated after subtracting the total energy consumed to produce the biomass energy? Knowing the ratio between energy output and input is a valid question when highly mechanized systems that consume fossil fuels are used to harvest and transport forest biomass for energy. We estimated the net energy generated from mechanical fuel...

  6. Surface energy balance in the ablation zone of Langfjordjøkelen, an arctic, maritime glacier in northern Norway

    NARCIS (Netherlands)

    Giesen, Rianne H.; Andreassen, Liss M.; Oerlemans, Johannes; van den Broeke, Michiel R.

    2014-01-01

    Glaciers in northern and southern Norway are subject to different daily and seasonal cycles of incoming solar radiation, which is presumably reflected in the importance of net solar radiation in their surface energy balance. We present a 3 year continuous record from an automatic weather station in

  7. Energy Balance and Performance Indices for Kraft Recovery Boilers; Standardmetod foer beraekning av energibalans oever sodapanna

    Energy Technology Data Exchange (ETDEWEB)

    Kjoerk, Anders

    2007-09-15

    It has been recognized that different rules exist in calculating energy flows to and from a Recovery boiler. In this report definitions are given with the intention that the branch should adopt a common position in reporting power production for the Swedish system with charge on emission of nitrogen oxides, for the EU Emissions Trading Scheme and for the electricity certificate system. Legislation and guidelines are described as also different standards for determination of boiler efficiency. The definition of the liquor heating value is discussed as also the different ways in which an energy balance could be set up. For the Emissions Trading Scheme a literature survey of interpretations made in other countries has been made. The recommendation is to define the heat input as the product of the virgin liquor flow and the net calorific value of virgin liquor. A net calorific value as defined in SS-ISO 1928 is determined in an environment with excess of oxygen and is consequently named net calorific value in oxidizing condition. In a Recovery boiler part of that heat is required for reduction of sulfur and a net calorific value in reducing condition are therefore defined in a branch specific way. The flow of liquor could be calculated using a heat balance based on steam generation. The envelope for that heat balance could be selected as to fit each individual installation; however some general recommendations are given. In reporting energy flow for the EU Emissions Trading Scheme and to EPA it is recommended to use the net calorific value in oxidizing condition. This definition should also be good for reporting to Statistics Sweden, Swedish Forest Industries Federation and for internal use. For reporting to the electricity certificate system the part of the total power production with origin from biofuel should be stated. The heat of reduction is not available for power production and consequently the recommendation is to use the net calorific value in reducing

  8. Nearly Net-Zero Exergy Districts as Models for Smart Energy Systems

    National Research Council Canada - National Science Library

    Şiir Kilkiş

    2017-01-01

    ... Östra Sala backe, which will have a new energy concept. The latter is analysed based on proposals for two phases that aim to reach a net-zero district target based on the quality of energy (exergy...

  9. The energy balance of the earth's surface : a practical approach

    NARCIS (Netherlands)

    Bruin, de H.A.R.

    1982-01-01

    This study is devoted to the energy balance of the earth's surface with a special emphasis on practical applications. A simple picture of the energy exchange processes that take place at the ground is the following. Per unit time and area an amount of radiant energy is supplied to the surface. This

  10. Top 10 Research Questions Related to Energy Balance

    Science.gov (United States)

    Shook, Robin P.; Hand, Gregory A.; Blair, Steven N.

    2014-01-01

    Obesity is the result of a mismatch between the amount of calories consumed and the amount of calories expended during an extended period of time. This relationship is described by the energy balance equation, which states the rate of change in energy storage depots in the body are equal to the rate of energy intake minus the rate of energy…

  11. Melanocortin Control of Energy Balance: Evidence from Rodent Models

    Science.gov (United States)

    De Jonghe, Bart C.; Hayes, Matthew R.; Bence, Kendra K.

    2011-01-01

    Regulation of energy balance is extremely complex, and involves multiple systems of hormones, neurotransmitters, receptors, and intracellular signals. As data have accumulated over the last two decades, the CNS melanocortin system is now identified as a prominent integrative network of energy balance controls in the mammalian brain. Here, we will review findings from rat and mouse models, which have provided an important framework in which to study melanocortin function. Perhaps most importantly, this review attempts for the first time to summarize recent advances in our understanding of the intracellular signaling pathways thought to mediate the action of melanocortin neurons and peptides in control of long term energy balance. Special attention will be paid to the roles of MC4R/MC3R, as well as downstream neurotransmitters within forebrain and hindbrain structures that illustrate the distributed control of melanocortin signaling in energy balance. In addition, distinctions and controversy between rodent species will be discussed. PMID:21553232

  12. Teaching a Model-based Climatology Using Energy Balance Simulation.

    Science.gov (United States)

    Unwin, David

    1981-01-01

    After outlining the difficulties of teaching climatology within an undergraduate geography curriculum, the author describes and evaluates the use of a computer assisted simulation to model surface energy balance and the effects of land use changes on local climate. (AM)

  13. Primary cilia in energy balance signaling and metabolic disorder

    OpenAIRE

    Lee, Hankyu; Song, Jieun; Jung, Joo Hyun; Ko, Hyuk Wan

    2015-01-01

    Energy homeostasis in our body system is maintained by balancing the intake and expenditure of energy. Excessive accumulation of fat by disrupting the balance system causes overweight and obesity, which are increasingly becoming global health concerns. Understanding the pathogenesis of obesity focused on studying the genes related to familial types of obesity. Recently, a rare human genetic disorder, ciliopathy, links the role for genes regulating structure and function of a cellular organell...

  14. Neural Control of Energy Balance: Translating Circuits to Therapies

    OpenAIRE

    Gautron, Laurent; Elmquist, Joel K.; Williams, Kevin W.

    2015-01-01

    Recent insights into the neural circuits controlling energy balance and glucose homeostasis have rekindled the hope for development of novel treatments for obesity and diabetes. However, many therapies contribute relatively modest beneficial gains with accompanying side effects, and the mechanisms of action for other interventions remain undefined. This Review summarizes current knowledge linking the neural circuits regulating energy and glucose balance with current and potential pharmacother...

  15. Energy and water cycle over the Tibetan plateau : surface energy balance and turbulent heat fluxes

    NARCIS (Netherlands)

    Su, Zhongbo; Zhang, Ting; Ma, Yaoming; Jia, Li; Wen, Jun

    2006-01-01

    This contribution presents an overview and an outlook of studies on energy and water cycle over the Tibetan plateau with focuses on the estimation of energy balance terms and turbulent heat fluxes. On the basis of the surface energy balance calculations, we show that the phenomena of the energy

  16. Energy and water cycle over the Tibetan Plateau: surface energy balance and turbulent heat fluxes

    NARCIS (Netherlands)

    Su, Z.; Zhang, T.; Ma, Y.; Jia, L.; Wen, J.

    2006-01-01

    This contribution presents an overview and an outlook of studies on energy and water cycle over the Tibetan plateau with focuses on the estimation of energy balance terms and turbulent heat fluxes. On the basis of the surface energy balance calculations, we show that the phenomena of the energy

  17. Physical activity, energy balance and obesity.

    Science.gov (United States)

    Luís Griera, José; María Manzanares, José; Barbany, Montserrat; Contreras, José; Amigó, Pilar; Salas-Salvadó, Jordi

    2007-10-01

    Obesity appears when energy intake exceeds energy expenditure. The most important variable compound of energy expenditure is physical activity. The global epidemics of obesity seem closely related to reduced physical activity and sedentariness widely increasing nowadays. Once obesity has developed, caloric intake becomes similar to energy expenditure. To lose weight, besides decreasing energy intake, energy expenditure must be increased. The promotion of physical activity is difficult and so the results of treatment of obesity are discouraging for doctors, other health professionals and patients. Proactive efforts from patients and health providers with an intensive feedback between them may be extremely helpful. Nevertheless, more studies are needed to provide better approaches on the role of physical activity for the prevention and treatment of obesity and for long-term weight-loss maintenance.

  18. An energy balance perspective on regional CO2-induced temperature changes in CMIP5 models

    Science.gov (United States)

    Räisänen, Jouni

    2017-05-01

    An energy balance decomposition of temperature changes is conducted for idealized transient CO2-only simulations in the fifth phase of the Coupled Model Intercomparison Project. The multimodel global mean warming is dominated by enhanced clear-sky greenhouse effect due to increased CO2 and water vapour, but other components of the energy balance substantially modify the geographical and seasonal patterns of the change. Changes in the net surface energy flux are important over the oceans, being especially crucial for the muted warming over the northern North Atlantic and for the seasonal cycle of warming over the Arctic Ocean. Changes in atmospheric energy flux convergence tend to smooth the gradients of temperature change and reduce its land-sea contrast, but they also amplify the seasonal cycle of warming in northern North America and Eurasia. The three most important terms for intermodel differences in warming are the changes in the clear-sky greenhouse effect, clouds, and the net surface energy flux, making the largest contribution to the standard deviation of annual mean temperature change in 34, 29 and 20 % of the world, respectively. Changes in atmospheric energy flux convergence mostly damp intermodel variations of temperature change especially over the oceans. However, the opposite is true for example in Greenland and Antarctica, where the warming appears to be substantially controlled by heat transport from the surrounding sea areas.

  19. Energy Use Consequences of Ventilating a Net-Zero Energy House

    Science.gov (United States)

    Ng, Lisa C.; Payne, W. Vance

    2016-01-01

    A Net-Zero Energy Residential Test Facility (NZERTF) has been constructed at the National Institute of Standards and Technology (NIST) in Gaithersburg, Maryland to demonstrate that a home similar in size, aesthetics, and amenities to those in the surrounding communities can achieve net-zero energy use over the course of a year while meeting the average electricity and water use needs of a family of four in the United States. The facility incorporates renewable energy and energy efficient technologies, including an air-to-air heat pump system, a solar photovoltaic system, a solar thermal domestic hot water system, and a heat recovery ventilation system sized to meet American Society of Heating, Refrigeration, and Air-Conditioning Engineers (ASHRAE) Standard 62.2-2010 ventilation requirements. The largest energy end use within the home was space conditioning, which included heat loss through the building envelope, ventilation air supplied by the heat recovery ventilator (HRV), and internal loads. While HRVs are often described as being able to save energy when compared to ventilating without heat recovery, there have been no studies using a full year of measured data that determine the thermal load and energy impacts of HRV-based ventilation on the central heating and cooling system. Over the course of a year, continuous operation of the HRV at the NZERTF resulted in an annual savings of 7 % in heat pump energy use compared with the hypothetical case of ventilating without heat recovery. The heat pump electrical use varied from an increase of 5 % in the cooling months to 36 % savings in the heating months compared with ventilation without heat recovery. The increase in the cooling months occurred when the outdoor temperature was lower than the indoor temperature, during which the availability of an economizer mode would have been beneficial. Nevertheless, the fan energy required to operate the selected HRV at the NZERTF paid for itself in the heat pump energy saved

  20. Energy Use Consequences of Ventilating a Net-Zero Energy House.

    Science.gov (United States)

    Ng, Lisa C; Payne, W Vance

    2016-03-05

    A Net-Zero Energy Residential Test Facility (NZERTF) has been constructed at the National Institute of Standards and Technology (NIST) in Gaithersburg, Maryland to demonstrate that a home similar in size, aesthetics, and amenities to those in the surrounding communities can achieve net-zero energy use over the course of a year while meeting the average electricity and water use needs of a family of four in the United States. The facility incorporates renewable energy and energy efficient technologies, including an air-to-air heat pump system, a solar photovoltaic system, a solar thermal domestic hot water system, and a heat recovery ventilation system sized to meet American Society of Heating, Refrigeration, and Air-Conditioning Engineers (ASHRAE) Standard 62.2-2010 ventilation requirements. The largest energy end use within the home was space conditioning, which included heat loss through the building envelope, ventilation air supplied by the heat recovery ventilator (HRV), and internal loads. While HRVs are often described as being able to save energy when compared to ventilating without heat recovery, there have been no studies using a full year of measured data that determine the thermal load and energy impacts of HRV-based ventilation on the central heating and cooling system. Over the course of a year, continuous operation of the HRV at the NZERTF resulted in an annual savings of 7 % in heat pump energy use compared with the hypothetical case of ventilating without heat recovery. The heat pump electrical use varied from an increase of 5 % in the cooling months to 36 % savings in the heating months compared with ventilation without heat recovery. The increase in the cooling months occurred when the outdoor temperature was lower than the indoor temperature, during which the availability of an economizer mode would have been beneficial. Nevertheless, the fan energy required to operate the selected HRV at the NZERTF paid for itself in the heat pump energy saved

  1. Targeting Net Zero Energy at Marine Corps Base Hawaii, Kaneohe Bay: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Burman, K.; Kandt, A.; Lisell, L.; Booth, S.

    2012-05-01

    This paper summarizes the results of an NREL assessment of Marine Corps Base Hawaii (MCBH), Kaneohe Bay to appraise the potential of achieving net zero energy status through energy efficiency, renewable energy, and hydrogen vehicle integration. In 2008, the U.S. Department of Defense's U.S. Pacific Command partnered with the U.S. Department of Energy's (DOE's) National Renewable Energy Laboratory (NREL) to assess opportunities for increasing energy security through renewable energy and energy efficiency at Hawaii military installations. DOE selected Marine Corps Base Hawaii (MCBH), Kaneohe Bay, to receive technical support for net zero energy assessment and planning funded through the Hawaii Clean Energy Initiative (HCEI). NREL performed a comprehensive assessment to appraise the potential of MCBH Kaneohe Bay to achieve net zero energy status through energy efficiency, renewable energy, and hydrogen vehicle integration. This paper summarizes the results of the assessment and provides energy recommendations. The analysis shows that MCBH Kaneohe Bay has the potential to make significant progress toward becoming a net zero installation. Wind, solar photovoltaics, solar hot water, and hydrogen production were assessed, as well as energy efficiency technologies. Deploying wind turbines is the most cost-effective energy production measure. If the identified energy projects and savings measures are implemented, the base will achieve a 96% site Btu reduction and a 99% source Btu reduction. Using excess wind and solar energy to produce hydrogen for a fleet and fuel cells could significantly reduce energy use and potentially bring MCBH Kaneohe Bay to net zero. Further analysis with an environmental impact and interconnection study will need to be completed. By achieving net zero status, the base will set an example for other military installations, provide environmental benefits, reduce costs, increase energy security, and exceed its energy goals and mandates.

  2. Energy balance measurement: when something is not better than nothing.

    Science.gov (United States)

    Dhurandhar, N V; Schoeller, D; Brown, A W; Heymsfield, S B; Thomas, D; Sørensen, T I A; Speakman, J R; Jeansonne, M; Allison, D B

    2015-07-01

    Energy intake (EI) and physical activity energy expenditure (PAEE) are key modifiable determinants of energy balance, traditionally assessed by self-report despite its repeated demonstration of considerable inaccuracies. We argue here that it is time to move from the common view that self-reports of EI and PAEE are imperfect, but nevertheless deserving of use, to a view commensurate with the evidence that self-reports of EI and PAEE are so poor that they are wholly unacceptable for scientific research on EI and PAEE. While new strategies for objectively determining energy balance are in their infancy, it is unacceptable to use decidedly inaccurate instruments, which may misguide health-care policies, future research and clinical judgment. The scientific and medical communities should discontinue reliance on self-reported EI and PAEE. Researchers and sponsors should develop objective measures of energy balance.

  3. Hypothalamic and brainstem neuronal circuits controlling homeostatic energy balance.

    Science.gov (United States)

    Schneeberger, Marc; Gomis, Ramon; Claret, Marc

    2014-02-01

    Alterations in adequate energy balance maintenance result in serious metabolic disturbances such as obesity. In mammals, this complex process is orchestrated by multiple and distributed neuronal circuits. Hypothalamic and brainstem neuronal circuits are critically involved in the sensing of circulating and local factors conveying information about the energy status of the organism. The integration of these signals culminates in the generation of specific and coordinated physiological responses aimed at regulating energy balance through the modulation of appetite and energy expenditure. In this article, we review current knowledge on the homeostatic regulation of energy balance, emphasizing recent advances in mouse genetics, electrophysiology, and optogenetic techniques that have greatly contributed to improving our understanding of this central process.

  4. The Global Energy Balance of Titan

    Science.gov (United States)

    Li, Liming; Nixon, Conor A.; Achterberg, Richard K.; Smith, Mark A.; Gorius, Nicolas J. P.; Jiang, Xun; Conrath, Barney J.; Gierasch, Peter J.; Simon-Miller, Amy A.; Flasar, F. Michael; hide

    2011-01-01

    We report the first measurement of the global emitted power of Titan. Longterm (2004-2010) observations conducted by the Composite Infrared Spectrometer (CIRS) onboard Cassini reveal that the total emitted power by Titan is (2.84 plus or minus 0.01) x 10(exp 8) watts. Together with previous measurements of the global absorbed solar power of Titan, the CIRS measurements indicate that the global energy budget of Titan is in equilibrium within measurement error. The uncertainty in the absorbed solar energy places an upper limit on the energy imbalance of 5.3%.

  5. Energy balance and metabolism after cancer treatment.

    Science.gov (United States)

    Tonorezos, Emily S; Jones, Lee W

    2013-12-01

    Unfavorable physiological, biological, and behavioral alterations during and following treatment for cancer may lead to chronic energy imbalance predisposing to a myriad of deleterious health conditions including obesity, dyslipidemia, and the metabolic syndrome. In addition to the cardiovascular and musculoskeletal effects of these conditions, energy imbalance and metabolic changes after cancer treatment can also affect cancer-related morbidity and mortality. To this end, lifestyle interventions such as diet and physical activity are especially relevant to mitigate the deleterious impact of chronic energy imbalance in cancer survivors. © 2013 Elsevier Inc. All rights reserved.

  6. Introduction to energy balance of biomass production; Introduccion al calculo del balance energetico de la produccion de Biomasa

    Energy Technology Data Exchange (ETDEWEB)

    Manzanares, P.

    1997-11-01

    During last years, energy crops have been envisaged as an interesting alternative to biomass residues utilization as renewable energy source. In this work, main parameters used in calculating the energy balance of an energy crop are analyzed. The approach consists of determining energy equivalents for the different inputs and outputs of the process, thus obtaining energy ratios of the system, useful to determine if the energy balance is positive, that is, if the system generates energy. Energy costs for inputs and assessment approaches for energy crop yields (output) are provided. Finally, as a way of illustration, energy balances of some representative energy crops are shown. (Author) 15 refs.

  7. Balancing of Network Energy using Observer Approach

    OpenAIRE

    Patharlapati, Sai Ram Charan

    2016-01-01

    Efficient energy use is primarily for any sensor networks to function for a longer time period. There have been many efficient schemes with various progress levels proposed by many researchers. Yet, there still more improvements are needed. This thesis is an attempt to make wireless sensor networks with further efficient on energy usage in the network with respect to rate of delivery of the messages. In sensor network architecture radio, sensing and actuators have influence over the power ...

  8. Energy Balance and Metabolism after Cancer Treatment

    OpenAIRE

    Tonorezos, Emily S.; Jones, Lee W.

    2013-01-01

    Unfavorable physiological, biological, and behavioral alterations during and following treatment for cancer may lead to chronic energy imbalance predisposing to a myriad of deleterious health conditions including obesity, dyslipidemia, and the metabolic syndrome. In addition to the cardiovascular and musculoskeletal effects of these conditions, energy imbalance and metabolic changes after cancer treatment can also affect cancer-related morbidity and mortality. To this end, lifestyle intervent...

  9. Energy balance in female distance runners.

    Science.gov (United States)

    Beidleman, B A; Puhl, J L; De Souza, M J

    1995-02-01

    Metabolic efficiency was assessed in ovulatory eumenorrheic female distance runners and untrained control subjects of similar age, body weight, and fat-free mass (FFM). Energy intake (EI) was estimated from 3-d dietary records. Energy expenditure (EE) was determined during the same 3-d period from individual heart rate oxygen uptake (HR/VO2) curves during rest and exercise, 24-h HR records, and the thermic effect of meals. The runners and control subjects did not differ in resting metabolic rate statistically adjusted for FFM (kJ/min), the thermic effect of a test meal (kJ/3 h), the energy cost of submaximal physical activity, or EI. EE was higher (P = 0.01) in the runners. Reported EI was lower than EE in both the runners (P = 0.007) and control subjects, (P = 0.006), resulting in energy deficits of -4131 +/- 1185 kJ/d and -1652 +/- 456 kJ/d, respectively. These female runners did not exhibit an enhanced metabolic efficiency compared with the control subjects. It is possible that the energy deficit for both the runners and control subjects was due to both restricted eating and underreporting during the measurement period. Additional studies using longer measurement periods, more sophisticated technology (ie, doubly labeled water, more subjects, and subjects of varying menstrual and energy intake status) are needed to truly answer this question.

  10. Carbon and energy balances for cellulosic biofuel crops in U.S. Midwest

    Science.gov (United States)

    Gerlfand, I.; Hamilton, S. K.; Robertson, G. P.

    2012-04-01

    Cellulosic biofuels produced on lands not used for food production have the potential to avoid competition for food and associated indirect land use costs. Understanding the carbon and energy balance implications for different cellulosic production systems is important for the development of decision making tools and policies. Here we present carbon and energy balances of alternative agricultural management. We use 20 years of data from KBS LTER experiments to produce farm level CO2 and energy balances for different management practices. Our analyses include four grain and four perrenial systems in the U.S. Midwest: corn (Zea mays) - soybean (Glycine max) - wheat (Triticum aestivum) rotations managed with (1) conventional tillage, (2) no till, (3) low chemical input, and (4) biologically-based (organic) practices; (5) continuous alfalfa (Medicago sativa); (6) Poplar; and (7,8) Successionnal fields, both fertilized and unfertilized. Measurements include fluxes of N2O and CH4, soil organic carbon change, agricultural yields, and agricultural inputs (e.g. fertilization and farm fuel use). Our results indicate that management decisions such as tillage and plant types have a great influence on the net carbon and energy balances and benefits of cellulosic biofuels production. Specifically, we show that cellulosic biofuels produced from an early successional, minimally managed system have a net C sequestration (i.e., negative C balance) of -841±46 gCO2e m-2 yr-1 vs. -594±93 gCO2e m-2 yr-1 for more productive and management intensive alfalfa, and vs. 232±157 gCO2e m-2 for poplar. The reference agricultural system (a conventionally tilled corn-soybean-wheat rotation) has net sequestration of -149±33 g CO2e m-2 yr-1. Among the annual grain crops, average energy costs of farming for the different systems ranged from 4.8 GJ ha-1 for the organic system to 7.1 GJ ha-1 for the conventional; the no-till system was also low at 4.9 GJ ha-1 and the low-chemical input system

  11. Organization of primary care practice for providing energy balance care.

    Science.gov (United States)

    Klabunde, Carrie N; Clauser, Steven B; Liu, Benmei; Pronk, Nicolaas P; Ballard-Barbash, Rachel; Huang, Terry T-K; Smith, Ashley Wilder

    2014-01-01

    Primary care physicians (PCPs) may not adequately counsel or monitor patients regarding diet, physical activity, and weight control (i.e., provide energy balance care). We assessed the organization of PCPs' practices for providing this care. The study design was a nationally representative survey conducted in 2008. The study setting was U.S. primary care practices. A total of 1740 PCPs completed two sequential questionnaires (response rate, 55.5%). The study measured PCPs' reports of practice resources, and the frequency of body mass index assessment, counseling, referral for further evaluation/management, and monitoring of patients for energy balance care. Descriptive statistics and logistic regression modeling were used. More than 80% of PCPs reported having information resources on diet, physical activity, or weight control available in waiting/exam rooms, but fewer billed (45%), used reminder systems (energy balance care. A total of 26% reported regularly assessing body mass index and always/often providing counseling as well as tracking patients for progress related to energy balance. In multivariate analyses, PCPs in practices with full electronic health records or those that bill for energy balance care provided this care more often and more comprehensively. There were strong specialty differences, with pediatricians more likely (odds ratio, 1.78; 95% confidence interval, 1.26-2.51) and obstetrician/gynecologists less likely (odds ratio, 0.28; 95% confidence interval, 0.17-0.44) than others to provide energy balance care. PCPs' practices are not well organized for providing energy balance care. Further research is needed to understand PCP care-related specialty differences.

  12. Turbulence induces metabolically costly behaviors and inhibits food capture in oyster larvae, causing net energy loss.

    Science.gov (United States)

    Fuchs, Heidi L; Specht, Jaclyn A; Adams, Diane K; Christman, Adam J

    2017-10-01

    Planktotrophic invertebrate larvae require energy to develop, disperse and settle successfully, and it is unknown how their energetics are impacted by turbulence. Ciliated larvae gain metabolic energy from their phytoplankton food to offset the energetic costs of growth, development and ciliary activity for swimming and feeding. Turbulence may affect the energetic balance by inducing behaviors that alter the metabolic costs and efficiency of swimming, by raising the encounter rate with food particles and by inhibiting food capture. We used experiments and an empirical model to quantify the net rate of energy gain, swimming efficiency and food capture efficiency for eyed oyster larvae (Crassostrea virginica) in turbulence. At dissipation rates representative of coastal waters, larvae lost energy even when food concentrations were very high. Both feeding activity and turbulence-induced behaviors incurred high metabolic costs. Swimming efficiency was concave up versus dissipation rate, suggesting that ciliary activity for food handling became more costly while swimming became more efficient with turbulence intensity. Though counter-intuitive, swimming may have become more efficient in turbulence because vorticity-induced rotation caused larvae to swim more horizontally, which requires less effort than swimming vertically against the pull of gravity. Overall, however, larvae failed to offset high activity costs with food energy gains because turbulence reduced food capture efficiency more than it enhanced food encounter rates. Younger, smaller larvae may have some energetic advantages, but competent larvae would lose energy at turbulence intensities they experience frequently, suggesting that turbulence-induced starvation may account for much of oysters' high larval mortality. © 2017. Published by The Company of Biologists Ltd.

  13. The Energy Balance of Corn Ethanol: An Update

    Energy Technology Data Exchange (ETDEWEB)

    Shapouri, Hosein [United States Dept. of Agriculture (USDA), Washington DC (United States); Duffield, James A. [United States Dept. of Agriculture (USDA), Washington DC (United States); Wang, Michael [Argonne National Lab. (ANL), Argonne, IL (United States)

    2002-07-01

    Studies conducted since the late 1970s have estimated the net energy value (NEV) of corn ethanol. However, variations in data and assumptions used among the studies have resulted in a wide range of estimates. This study identifies the factors causing this wide variation and develops a more consistent estimate.

  14. Energy balance in coherent electromagnetic radiation

    CERN Document Server

    Coisson, R

    1994-01-01

    Bunched charges, as in the 'free electron laser', radiate more energy than unbunched ones. For a better understanding of how the forces between particles determine the conservation of energy, we take the simple model of two charges within a wavelength of a sinusodoidal wave, and show that the relative phase of the particle's motion with respect to the wave is modified by the force between the two particles, and this explains the extra work done by the wave. The phase shift is proportional to the emitted field and depends on the retardation (particle distance divided by speed of light), and turns out to be independent of distance. (author)

  15. Control of Greenhouse Gas Emissions by Optimal DER Technology Investment and Energy Management in Zero-Net-Energy Buildings

    Energy Technology Data Exchange (ETDEWEB)

    Stadler, Michael; Siddiqui, Afzal; Marnay, Chris; Aki, Hirohisa; Lai, Judy

    2009-08-10

    The U.S. Department of Energy has launched the commercial building initiative (CBI) in pursuit of its research goal of achieving zero-net-energy commercial buildings (ZNEB), i.e. ones that produce as much energy as they use. Its objective is to make these buildings marketable by 2025 such that they minimize their energy use through cutting-edge, energy-efficiency technologies and meet their remaining energy needs through on-site renewable energy generation. This paper examines how such buildings may be implemented within the context of a cost- or CO2-minimizing microgrid that is able to adopt and operate various technologies: photovoltaic modules (PV) and other on-site generation, heat exchangers, solar thermal collectors, absorption chillers, and passive/demand-response technologies. A mixed-integer linear program (MILP) that has a multi-criteria objective function is used. The objective is minimization of a weighted average of the building's annual energy costs and CO2 emissions. The MILP's constraints ensure energy balance and capacity limits. In addition, constraining the building's energy consumed to equal its energy exports enables us to explore how energy sales and demand-response measures may enable compliance with the ZNEB objective. Using a commercial test site in northernCalifornia with existing tariff rates and technology data, we find that a ZNEB requires ample PV capacity installed to ensure electricity sales during the day. This is complemented by investment in energy-efficient combined heat and power (CHP) equipment, while occasional demand response shaves energy consumption. A large amount of storage is also adopted, which may be impractical. Nevertheless, it shows the nature of the solutions and costs necessary to achieve a ZNEB. Additionally, the ZNEB approach does not necessary lead to zero-carbon (ZC) buildings as is frequently argued. We also show a multi-objective frontier for the CA example, whichallows us to estimate the

  16. Cognitive determinants of energy balance-related behaviours: Measurement issues

    NARCIS (Netherlands)

    S.P.J. Kremers (Stef); T.L.S. Visscher (Tommy); J.C. Seidell (Jaap); W. van Mechelen (Willem); J. Brug (Hans)

    2005-01-01

    textabstractThe burden of disease as a result of overweight and obesity calls for in-depth examination of the main causes of behavioural actions responsible for weight gain. Since weight gain is the result of a positive energy balance, these behavioural actions are referred to as 'energy

  17. Teaching Mass and Energy Balances by Experiment

    Science.gov (United States)

    Orbey, Nese; De Jesús Vega, Marisel; Zalluhoglu, Fulya Sudur

    2017-01-01

    A general tank-draining problem was used as an experimental project in two undergraduate-level chemical engineering courses. The project aimed to illustrate the critical nature of experimentation in addition to use of mass and energy conservation principles in developing mathematical models that correctly describes a system. The students designed…

  18. Sustainable urban regeneration based on energy balance

    NARCIS (Netherlands)

    Van Timmeren, A.; Zwetsloot, J.; Brezet, H.; Silvester, S.

    2012-01-01

    In this paper, results are reported of a technology assessment of the use and integration of decentralized energy systems and storage devices in an urban renewal area. First the general context of a different approach based on 'rethinking' and the incorporation of ongoing integration of coming

  19. Development of Energy Balances for the State of California

    Energy Technology Data Exchange (ETDEWEB)

    Murtishaw, Scott; Price, Lynn; de la Rue du Can, Stephane; Masanet, Eric; Worrell, Ernst; Sahtaye, Jayant

    2005-12-01

    Analysts assessing energy policies and energy modelers forecasting future trends need to have access to reliable and concise energy statistics. Lawrence Berkeley National Laboratory evaluated several sources of California energy data, primarily from the California Energy Commission and the U.S. Energy Information Administration, to develop the California Energy Balance Database (CALEB). This database manages highly disaggregated data on energy supply, transformation, and end-use consumption for each type of energy commodity from 1990 to the most recent year available (generally 2001) in the form of an energy balance, following the methodology used by the International Energy Agency. This report presents the data used for CALEB and provides information on how the various data sources were reconciled. CALEB offers the possibility of displaying all energy flows in numerous ways (e.g.,physical units, Btus, petajoules, different levels of aggregation), facilitating comparisons among the different types of energy commodities and different end-use sectors. In addition to displaying energy data, CALEB can also be used to calculate state-level energy-related carbon dioxide emissions using the methodology of the Intergovernmental Panel on Climate Change.

  20. Federal Campuses Handbook for Net Zero Energy, Water, and Waste

    Energy Technology Data Exchange (ETDEWEB)

    None

    2017-08-14

    In 2015, the U.S. Department of Energy’s Office Energy Efficiency and Renewable Energy (EERE) defined a zero energy campus as "an energy-efficient campus where, on a source energy basis, the actual annual delivered energy is less than or equal to the on-site renewable exported energy." This handbook is focused on applying the EERE definition of zero energy campuses to federal sector campuses. However, it is not intended to replace, substitute, or modify any statutory or regulatory requirements and mandates.

  1. National energy balance - 1995 of Brazil. Based on 1994

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-12-31

    Consolidated data of production, consumption and external dependence of energy are presented, as also the sectorial composition of the consumption of the different groups of energy sources. For each primary and secondary source the production, import, export, variations in inventories, losses, adjustments and total consumption are analyzed. Balances of transformation centers, characterizing the energy the energy processed, the energy produced and the respective losses in transformation are shown. Finally energy resources and reserves of primary sources are described with respective methodologies for estimating them. 60 figs., 107 tabs.

  2. Climatological evaluation of some fluxes of the surface energy and soil water balances over France

    Directory of Open Access Journals (Sweden)

    E. M. Choisnel

    Full Text Available This paper presents some statistical evaluations of the surface energy and soil water balance fluxes, for a prairie-type canopy, using the Earth model with a double-reservoir system for the management of the soil water reserve and the regulation of actual evapotranspiration. The mean values of these fluxes are estimated from energy and water balance simulations done on a 30-year climatic reference period (1951–1980. From values of these fluxes calculated for each meteorological synoptic station, mappings of net radiation, actual evapotranspiration, drainage and conduction fluxes have been made over French territory. Lastly, a few conclusions pertaining to the spatial variability of fluxes and to the partition of rainfall between run-off and drainage on the one hand and replenishment of the soil water reserve on the other hand are drawn from these preliminary results.

  3. Energy and momentum analysis of the deployment dynamics of nets in space

    Science.gov (United States)

    Botta, Eleonora M.; Sharf, Inna; Misra, Arun K.

    2017-11-01

    In this paper, the deployment dynamics of nets in space is investigated through a combination of analysis and numerical simulations. The considered net is deployed by ejecting several corner masses and thanks to momentum and energy transfer from those to the innermost threads of the net. In this study, the net is modeled with a lumped-parameter approach, and assumed to be symmetrical, subject to symmetrical initial conditions, and initially slack. The work-energy and momentum conservation principles are employed to carry out centroidal analysis of the net, by conceptually partitioning the net into a system of corner masses and the net proper and applying the aforementioned principles to the corresponding centers of mass. The analysis provides bounds on the values that the velocity of the center of mass of the corner masses and the velocity of the center of mass of the net proper can individually attain, as well as relationships between these and different energy contributions. The analytical results allow to identify key parameters characterizing the deployment dynamics of nets in space, which include the ratio between the mass of the corner masses and the total mass, the initial linear momentum, and the direction of the initial velocity vectors. Numerical tools are employed to validate and interpret further the analytical observations. Comparison of deployment results with and without initial velocity of the net proper suggests that more complete and lasting deployment can be achieved if the corner masses alone are ejected. A sensitivity study is performed for the key parameters identified from the energy/momentum analysis, and the outcome establishes that more lasting deployment and safer capture (i.e., characterized by higher traveled distance) can be achieved by employing reasonably lightweight corner masses, moderate shooting angles, and low shooting velocities. A comparison with current literature on tether-nets for space debris capture confirms overall

  4. Energy and heat balance in wet DCT

    Energy Technology Data Exchange (ETDEWEB)

    Saxena, Viren; Moser, Alexander; Schaefer, Michael; Ritschel, Michael [BorgWarner Drivetrain Engineering GmbH, Ketsch (Germany)

    2012-11-01

    Wet clutch systems are well known for their thermal robustness and versatility in a wide range of automotive applications. Conventional automatics have used them for a long time as torque converter lock-up clutches, shift elements and launch clutches. With the development of DCTs, wet clutch technology has evolved in terms of launch and shift performance, controllability, robustness and efficiency. This paper discusses improvements in the wet clutch and their impact on today's vehicle applications in terms of heat and energy management. Thermal robustness is a crucial aspect for an automatic transmission. In addition to the clutch thermal performance, the influence of transmission oil cooler and oil sump warm-up behavior are discussed. Based on our latest development activities, test results and simulations, we shall discuss the latest friction material enhancement and its impact on DCTs in terms of efficiency and performance. Drag loss is a much-discussed topic during the development of wet clutch systems. This paper discusses in detail the cause and break-up of various energy losses in a wet DCT. Efficient energy management strategies for actuation systems, cooling, and lubrication, clutch apply, and pre-selection in modern power trains with engine start / stop are evaluated based on the latest test and simulation results. Finally, the paper summarizes the performance and efficiency optimized moist clutch system. (orig.)

  5. Energy Balance: An Overview With Emphasis on Children

    Science.gov (United States)

    Tam, Charmaine S.; Ravussin, Eric

    2014-01-01

    Childhood obesity is a significant public health problem, affecting one in five children in the United States. At the crux of this issue is a dysregulation of energy intake and energy expenditure. This review will provide an overview on energy and nutrient balance. We discuss energy balance studies in children using indirect and direct measures, and focus particularly on obesity as a deleterious consequence in childhood survivors of cancer. Obesity affects 11–57% of children with acute lymphoblastic leukemia, probably due to increased energy intake and reduced energy expenditure secondary to reduced habitual activity caused by fatigue. However, most of the studies in children with leukemia are retrospective, use BMI as a measure of obesity, and are inconclusive about the impact of the type of treatment on the development of obesity later in life. To better understand the etiology of obesity in both healthy and sick children, we need to undertake nutrient balance studies with appropriate measures of fat mass and fat distribution while keeping in mind the influence of normal tissue growth and puberty on energy balance. PMID:22021150

  6. Energy balance: an overview with emphasis on children.

    Science.gov (United States)

    Tam, Charmaine S; Ravussin, Eric

    2012-01-01

    Childhood obesity is a significant public health problem, affecting one in five children in the United States. At the crux of this issue is a dysregulation of energy intake and energy expenditure. This review will provide an overview on energy and nutrient balance. We discuss energy balance studies in children using indirect and direct measures, and focus particularly on obesity as a deleterious consequence in childhood survivors of cancer. Obesity affects 11-57% of children with acute lymphoblastic leukemia, probably due to increased energy intake and reduced energy expenditure secondary to reduced habitual activity caused by fatigue. However, most of the studies in children with leukemia are retrospective, use BMI as a measure of obesity, and are inconclusive about the impact of the type of treatment on the development of obesity later in life. To better understand the etiology of obesity in both healthy and sick children, we need to undertake nutrient balance studies with appropriate measures of fat mass and fat distribution while keeping in mind the influence of normal tissue growth and puberty on energy balance. Copyright © 2011 Wiley Periodicals, Inc.

  7. Neurotrophins and the regulation of energy balance and body weight.

    Science.gov (United States)

    Rios, M

    2014-01-01

    Complex interactions between the brain and peripheral tissues mediate the effective control of energy balance and body weight. Hypothalamic and hindbrain neural circuits integrate peripheral signals informing the nutritional status of the animal and in response regulate nutrient intake and energy utilization. Obesity and its many medical complications emerge from the dysregulation of energy homeostasis. Excessive weight gain might also arise from alterations in reward systems of the brain that drive consumption of calorie dense, palatable foods in the absence of an energy requirement. Several neurotrophins, most notably brain-derived neurotrophic factor, have been implicated in the molecular and cellular processes underlying body weight regulation. Here, we review investigations interrogating their roles in energy balance and reward centers of the brain impacting feeding behavior and energy expenditure.

  8. Energy saving for OpenFlow switch on the NetFPGA platform based on queue engineering.

    Science.gov (United States)

    Vu, Tran Hoang; Luc, Vu Cong; Quan, Nguyen Trung; Thanh, Nguyen Huu; Nam, Pham Ngoc

    2015-01-01

    Data centers play an important role in our daily activities. The increasing demand on data centers in both scale and size has led to huge energy consumption that rises the cost of data centers. Besides, environmental impacts also increase considerably due to a large amount of carbon emissions. In this paper, we present a design aimed at green networking by reducing the power consumption for routers and switches. Firstly, we design the Balance Switch on the NetFPGA platform to save consumed energy based on Queue Engineering. Secondly, we design the test-bed system to precisely measure the consumed energy of our switches. Experimental results show that energy saving of our switches is about 30% - 35% of power consumption according to variation of input traffic compared with normal Openflow Switch. Finally, we describe performance evaluations.

  9. The energy balance within a bubble column evaporator

    Science.gov (United States)

    Fan, Chao; Shahid, Muhammad; Pashley, Richard M.

    2017-11-01

    Bubble column evaporator (BCE) systems have been studied and developed for many applications, such as thermal desalination, sterilization, evaporative cooling and controlled precipitation. The heat supplied from warm/hot dry bubbles is to vaporize the water in various salt solutions until the solution temperature reaches steady state, which was derived into the energy balance of the BCE. The energy balance and utilization involved in each BCE process form the fundamental theory of these applications. More importantly, it opened a new field for the thermodynamics study in the form of heat and vapor transfer in the bubbles. In this paper, the originally derived energy balance was reviewed on the basis of its physics in the BCE process and compared with new proposed energy balance equations in terms of obtained the enthalpy of vaporization (ΔH vap) values of salt solutions from BCE experiments. Based on the analysis of derivation and ΔH vap values comparison, it is demonstrated that the original balance equation has high accuracy and precision, within 2% over 19-55 °C using improved systems. Also, the experimental and theoretical techniques used for determining ΔH vap values of salt solutions were reviewed for the operation conditions and their accuracies compared to the literature data. The BCE method, as one of the most simple and accurate techniques, offers a novel way to determine ΔH vap values of salt solutions based on its energy balance equation, which had error less than 3%. The thermal energy required to heat the inlet gas, the energy used for water evaporation in the BCE and the energy conserved from water vapor condensation were estimated in an overall energy balance analysis. The good agreement observed between input and potential vapor condensation energy illustrates the efficiency of the BCE system. Typical energy consumption levels for thermal desalination for producing pure water using the BCE process was also analyzed for different inlet air

  10. Sugars: hedonic aspects, neuroregulation, and energy balance.

    Science.gov (United States)

    Levine, Allen S; Kotz, Catherine M; Gosnell, Blake A

    2003-10-01

    The prevalence of obesity has increased dramatically in recent years in the United States, with similar patterns seen in several other countries. Although there are several potential explanations for this dramatic increase in obesity, dietary influences are a contributing factor. An inverse correlation between dietary sugar intake and body mass index has been reported, suggesting beneficial effects of carbohydrate intake on body mass index. In this review we discuss how sugars interact with regulatory neurochemicals in the brain to affect both energy intake and energy expenditure. These neurochemicals appear to be involved in dietary selection, and sugars and palatable substances affect neurochemical changes in the brain. For example, rats that drink sucrose solutions for 3 wk have major changes in neuronal activity in the limbic area of the brain, a region involved in pleasure and other emotions. We also investigate the relations between sucrose (and other sweet substances), drugs of abuse, and the mesolimbic dopaminergic system. The presence of sucrose in an animal's cage can affect the animals desire to self-administer drugs of abuse. Also, an animal's level of sucrose preference can predict its desire to self-administer cocaine. Such data suggest a relation between sweet taste and drug reward, although the relevance to humans is unclear. Finally, we address the influence of sugar on body weight control. For example, sucrose feeding for 2 wk decreases the efficiency of energy utilization and increases gene expression of uncoupling protein 3 in muscle, suggesting that sucrose may influence uncoupling protein 3 activity and contribute to changes in metabolic efficiency and thus regulation of body weight.

  11. Modeling Plant-Atmosphere Interactions and Ramifications on the Surface Energy Balance in Arctic Ecosystems

    Science.gov (United States)

    Linn, R.; Cunningham, P.; Wilson, C. J.

    2011-12-01

    There is broad recognition that the melting of the permafrost in arctic landscapes could have pronounced global climatological impacts. The evolution of the permafrost and its impacts on the carbon and water balances is directly related to balances in the surface energy budget. There are a number of factors that are expected to impact the net heat flux at the surface of the soil including regional atmospheric conditions. However, ultimately this surface energy balance is controlled by local processes including evaporation from the surface, transpiration from vegetation as well as radiative and convective heat transfer. These four processes are directly impacted by coupling between the vegetation and atmosphere, and thus depend heavily upon the horizontal and vertical vegetation structure. If shrubs replace grasses in the arctic ecosystem there will be net shifts in the heat transfer to the ground. For example, the solar radiation that is absorbed by shrubs is separated from the soil by a stem space through which winds blow. In order for the energy to reach the soil it must warm the air and then warm the soil, however some of the warm air is mixed into the atmosphere and diffused. This structural feature can act in a fashion similar to a closed canopy forest, which frequently have cooler temperatures below the canopy than nearby grasslands An atmospheric hydrodynamics model, HIGRAD, has been enhanced to simulate complex, three-dimensional plant-atmosphere interactions at extremely high resolution (~0.1 m in all three directions). The model represents the transport of momentum, heat, moisture, and CO2 and their exchange between the vegetation and surrounding air. HIGRAD was used to simulate coupled atmosphere/vegetation systems representative of heterogeneous shrub and tussock grass surrounding a thermokarst. In these simulations shrubs, uneven grasses, and a thermokarst depression are explicitly resolved, and atmospheric conditions are similar to those of summer

  12. District heating biofuel burner efficiency and energy balance

    OpenAIRE

    Okoro, Oluwashola Aderemi

    2015-01-01

    District heating is an optimal system of distributing heat to residential building in a centralized location through pipeline networks. The district heating of woodchip is cost effective, improve energy efficiency, reduce gas emissions and improve energy security. The thermal efficiency and energy balance in a boiler is obtained by combustion analysis of the wood (fuel). In this report, the district heating bio fuel burner in Skien Fjernvarme is considered. The capacity of the boiler is 6MW a...

  13. Economic Investigation of Community-Scale Versus Building Scale Net-Zero Energy

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez, Nicholas; Katipamula, Srinivas; Brambley, Michael R.; Reddy, T. A.

    2009-12-31

    The study presented in this report examines issues concerning whether achieving net-zero energy performance at the community scale provides economic and potentially overall efficiency advantages over strategies focused on individual buildings.

  14. Energy balance Flanders 1997: disparity method; Energiebalans Vlaanderen 1997: Verschilmethode

    Energy Technology Data Exchange (ETDEWEB)

    Aernouts, K.; Moorkens, I.

    1999-10-01

    In this report, the energy balance of Flanders for 1997 is presented, together with an estimation of the CO2-emissions. Apart from data about 1997, comparable data about the 1990-1996 period are presented in order to give a picture of the evolution of both energy consumption and the CO2-emissions in Flanders. The energy balance is calculated by subtracting the energy bal lances of the Walloon and Brussels region from the Belgian energy balance. Afterwards, these results were corrected as far as specific Flemish energy data are available. The method is described in detail in a separate report. For the calculation of the CO2-emissions, the revised 1996 IPPC guidelines for national greenhouse gas inventories are used. In 1997, the primary energy consumption in Flanders was 1,722.0 PJ, the gross inland consumption was 1,442.4 PJ. The final energy consumption amounted to 1,057.0 PJ. The total CO2-emissions were 76,764 kton (emissions from international aviation and marine bunkering excluded). Compared to 1990, the gros inland consumption has increased with 25.8 per cent by 1997, the final energy consumption with 31.3 per cent and the CO2-consumption with 12.0 per cent.

  15. Beam Energy and System Size Dependence of Dynamical Net Charge Fluctuations

    Energy Technology Data Exchange (ETDEWEB)

    STAR Coll

    2008-07-21

    We present measurements of net charge fluctuations in Au + Au collisions at {radical}s{sub NN} = 19.6, 62.4, 130, and 200 GeV, Cu + Cu collisions at {radical}s{sub NN} = 62.4, 200 GeV, and p + p collisions at {radical}s = 200 GeV using the dynamical net charge fluctuations measure {nu}{sub {+-},dyn}. We observe that the dynamical fluctuations are non-zero at all energies and exhibit a modest dependence on beam energy. A weak system size dependence is also observed. We examine the collision centrality dependence of the net charge fluctuations and find that dynamical net charge fluctuations violate 1/N{sub ch} scaling, but display approximate 1/N{sub part} scaling. We also study the azimuthal and rapidity dependence of the net charge correlation strength and observe strong dependence on the azimuthal angular range and pseudorapidity widths integrated to measure the correlation.

  16. A mobile system for quantifying the spatial variability of the surface energy balance: design and application.

    Science.gov (United States)

    Wohlfahrt, Georg; Tasser, Erich

    2015-05-01

    We present a mobile device for the quantification of the small-scale (a few square meters) spatial variability in the surface energy balance components and several auxiliary variables of short-statured (ecological research questions. The potential of the new device is demonstrated through four selected case studies, which cover the issues of net radiation heterogeneity within the footprint of eddy covariance flux measurements due to (1) land use and (2) slope and aspect of the underlying surface, (3) controls on landscape-scale variability in soil temperature and albedo and (4) the estimation of evapotranspiration based exclusively on measurements with the mobile device.

  17. Energy balance at a crossroads: translating the science into action.

    Science.gov (United States)

    Manore, Melinda M; Brown, Katie; Houtkooper, Linda; Jakicic, John; Peters, John C; Smith Edge, Marianne; Steiber, Alison; Going, Scott; Gable, Lisa Guillermin; Krautheim, Ann Marie

    2014-07-01

    One of the major challenges facing the United States is the high number of overweight and obese adults and the growing number of overweight and unfit children and youth. To improve the nation's health, young people must move into adulthood without the burden of obesity and its associated chronic diseases. To address these issues, the American College of Sports Medicine, the Academy of Nutrition and Dietetics, and the US Department of Agriculture/Agriculture Research Service convened an expert panel meeting in October 2012 titled "Energy Balance at a Crossroads: Translating the Science into Action." Experts in the fields of nutrition and exercise science came together to identify the biological, lifestyle, and environmental changes that will most successfully help children and families attain and manage energy balance and tip the scale toward healthier weights. Two goals were addressed: 1) professional training and 2) consumer/community education. The training goal focused on developing a comprehensive strategy to facilitate the integration of nutrition and physical activity (PA) using a dynamic energy balance approach for regulating weight into the training of undergraduate and graduate students in dietetics/nutrition science, exercise science/PA, and pre-K-12 teacher preparation programs and in training existing cooperative extension faculty. The education goal focused on developing strategies for integrating dynamic energy balance into nutrition and PA educational programs for the public, especially programs funded by federal/state agencies. The meeting expert presenters and participants addressed three key areas: 1) biological and lifestyle factors that affect energy balance, 2) undergraduate/graduate educational and training issues, and 3) best practices associated with educating the public about dynamic energy balance. Specific consensus recommendations were developed for each goal.

  18. Spreading The Net: The Multiple Benefits Of Energy Efficiency Improvements

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2012-07-01

    Improving energy efficiency can deliver a range of benefits to the economy and society. However energy efficiency programmes are often evaluated only on the basis of the energy savings they deliver. As a result, the full value of energy efficiency improvements in both national and global economies may be significantly underestimated. This also means that energy efficiency policy may not be optimised to target the potential of the full range of outcomes possible. Moreover, when the merit of energy efficiency programmes is judged solely on reductions in energy demand, programmes are susceptible to criticisms related to the rebound effect when the energy savings are less than expected due to other welfare gains. There are several reasons why the full range of outcomes from energy efficiency policy is not generally evaluated. First, it is due to the non-market, somewhat intangible, nature of the socioeconomic benefits, which makes them difficult to quantify. Second, the effects due to energy efficiency alone can be complex to isolate and to determine causality. Third, evaluators and policy makers working in the energy efficiency sphere are usually energy professionals, working for an energy agency or ministry, with little experience of how energy efficiency might impact other non-energy sectors. The result is an under-appreciation – and related underinvestment – in energy efficiency, and as a consequence, missed opportunities and benefits. These foregone benefits represent the ‘opportunity cost’ of failing to adequately evaluate and prioritize energy efficiency investments. The objective of this report is to fully outline the array of different benefits from improved energy efficiency and investigate their implications for policy design. By better understanding the different benefits arising from energy efficiency it should be easier for policy makers to prioritise the most significant outcomes, in addition to energy savings, in optimising energy efficiency

  19. Energy balance analysis in non linear dynamic equivalent systems.

    Directory of Open Access Journals (Sweden)

    Carlos Iturregui Arranz

    2018-01-01

    The powers, energies and works developed are analyzed, creating a precise balance since energy enters selectively. Hence, an equivalent damping containing a viscous and hysteretic part is predictable, accordingly to the variation of the building’s nonlinear properties. Evaluation of the adequateness and safety level are also obtainable. The controlled parameters contrasted with the balance predicts the structure’s MDOF situation, at any moment related with seismic events. This methodology can be used to stablish a systematic control of nonlinearities for other structural schemes.

  20. Neural control of energy balance: translating circuits to therapies.

    Science.gov (United States)

    Gautron, Laurent; Elmquist, Joel K; Williams, Kevin W

    2015-03-26

    Recent insights into the neural circuits controlling energy balance and glucose homeostasis have rekindled the hope for development of novel treatments for obesity and diabetes. However, many therapies contribute relatively modest beneficial gains with accompanying side effects, and the mechanisms of action for other interventions remain undefined. This Review summarizes current knowledge linking the neural circuits regulating energy and glucose balance with current and potential pharmacotherapeutic and surgical interventions for the treatment of obesity and diabetes. Copyright © 2015 Elsevier Inc. All rights reserved.

  1. Endocrine-disrupting chemicals and the regulation of energy balance.

    Science.gov (United States)

    Nadal, Angel; Quesada, Ivan; Tudurí, Eva; Nogueiras, Rubén; Alonso-Magdalena, Paloma

    2017-09-01

    Energy balance involves the adjustment of food intake, energy expenditure and body fat reserves through homeostatic pathways. These pathways include a multitude of biochemical reactions, as well as hormonal cues. Dysfunction of this homeostatic control system results in common metabolism-related pathologies, which include obesity and type 2 diabetes mellitus. Metabolism-disrupting chemicals (MDCs) are a particular class of endocrine-disrupting chemicals that affect energy homeostasis. MDCs affect multiple endocrine mechanisms and thus different cell types that are implicated in metabolic control. MDCs affect gene expression and the biosynthesis of key enzymes, hormones and adipokines that are essential for controlling energy homeostasis. This multifaceted spectrum of actions precludes compensatory responses and favours metabolic disorders. Herein, we review the main mechanisms used by MDCs to alter energy balance. This work should help to identify new MDCs, as well as novel targets of their action.

  2. Effects of Genotype by Environment Interactions on Milk Yield, Energy Balance, and Protein Balance

    NARCIS (Netherlands)

    Beerda, B.; Ouweltjes, W.; Sebek, L.B.J.; Windig, J.J.; Veerkamp, R.F.

    2007-01-01

    Increases in genetic merit for milk yield are associated with increases in mobilization of body reserves. This study assessed the effects of genotype by environment (GxE) interactions on milk yield and energy and protein balances. Heifers (n = 100) with high or low genetic merit for milk yield were

  3. The Spanish Wind Energy Market. Balance and Outlooks; El Mercado Eolico Espanol. Balance y Perspectivas

    Energy Technology Data Exchange (ETDEWEB)

    Varela, M. [CIEMAT. Madrid (Spain)

    1999-06-01

    The present work accomplishes a revision to the situation of the wind market in Spain, its recent evolution, its regional distribution, the principal actors of the market (manufacturers, promoters). The balance includes a review of the programs of institutional support to wind energy, an analysis of the current installation costs and electricity production costs. Finally, other variables related the integration of wind energy are analysed, as the potential of employment generation or the associated environmental factors. (Author) 5 refs.

  4. Model Property Based Material Balance and Energy Conservation Analysis for Process Industry Energy Transfer Systems

    OpenAIRE

    Fumin Ma; Gregory M. P. O’Hare; Tengfei Zhang; Michael J. O’Grady

    2015-01-01

    Conventional historical data based material and energy balance analyses are static and isolated computations. Such methods cannot embody the cross-coupling effect of energy flow, material flow and information flow in the process industry; furthermore, they cannot easily realize the effective evaluation and comparison of different energy transfer processes by alternating the model module. In this paper, a novel method for material balance and energy conservation analysis of process industry en...

  5. ENERGY BALANCE AND CO2 EXCHANGE BEHAVIOUR IN SUB-TROPICAL YOUNG PINE (Pinus roxburghii PLANTATION

    Directory of Open Access Journals (Sweden)

    B. K. Bhattacharya

    2012-08-01

    Full Text Available A study was conducted to understand the seasonal and annual energy balance behaviour of young and growing sub-tropical chir pine (Pinus roxburghii plantation of eight years age in the Doon valley, India and its coupling with CO2 exchange. The seasonal cycle of dekadal daytime latent heat fluxes mostly followed net radiation cycle with two minima and range between 50–200 Wm-2 but differed from the latter during the period when soil wetness and cloudiness were not coupled. Dekadal evaporative fraction closely followed the seasonal dryness-wetness cycle thus minimizing the effect of wind on energy partitioning as compared to diurnal variation. Daytime latent heat fluxes were found to have linear relationship with canopy net assimilation rate (Y = 0.023X + 0.171, R2 = 0.80 though nonlinearity exists between canopy latent heat flux and hourly net CO2 assimilation rate . Night-time plant respiration was found to have linear relationship (Y = 0.088 + 1.736, R2 = 0.72 with night-time average vapour pressure deficit (VPD. Daily average soil respiration was found to be non-linearly correlated to average soil temperatures (Y = -0.034X2 + 1.676X – 5.382, R2 = 0.63 The coupled use of empirical models, seasonal energy fluxes and associated parameters would be useful to annual water and carbon accounting in subtropical pine ecosystem of India in the absence high-response eddy covariance tower.

  6. ENERGY-NET (Energy, Environment and Society Learning Network): Enhancing opportunities for learning using an Earth systems science framework

    Science.gov (United States)

    Elliott, E. M.; Bain, D. J.; Divers, M. T.; Crowley, K. J.; Povis, K.; Scardina, A.; Steiner, M.

    2012-12-01

    We describe a newly funded collaborative NSF initiative, ENERGY-NET (Energy, Environment and Society Learning Network), that brings together the Carnegie Museum of Natural History (CMNH) with the Learning Science and Geoscience research strengths at the University of Pittsburgh. ENERGY-NET aims to create rich opportunities for participatory learning and public education in the arena of energy, the environment, and society using an Earth systems science framework. We build upon a long-established teen docent program at CMNH and to form Geoscience Squads comprised of underserved teens. Together, the ENERGY-NET team, including museum staff, experts in informal learning sciences, and geoscientists spanning career stage (undergraduates, graduate students, faculty) provides inquiry-based learning experiences guided by Earth systems science principles. Together, the team works with Geoscience Squads to design "Exploration Stations" for use with CMNH visitors that employ an Earth systems science framework to explore the intersecting lenses of energy, the environment, and society. The goals of ENERGY-NET are to: 1) Develop a rich set of experiential learning activities to enhance public knowledge about the complex dynamics between Energy, Environment, and Society for demonstration at CMNH; 2) Expand diversity in the geosciences workforce by mentoring underrepresented teens, providing authentic learning experiences in earth systems science and life skills, and providing networking opportunities with geoscientists; and 3) Institutionalize ENERGY-NET collaborations among geosciences expert, learning researchers, and museum staff to yield long-term improvements in public geoscience education and geoscience workforce recruiting.

  7. Life Cycle Cost Analysis of a Multi-Storey Residential Net Zero Energy Building in Denmark

    DEFF Research Database (Denmark)

    Marszal, Anna Joanna; Heiselberg, Per

    2011-01-01

    renewable energy technologies? This analysis adopts the LCC methodology and uses a multi-family Net ZEB to find the answer to this question. Moreover, it looks at the issue from the building owner’s perspective, hence it should be seen as a private economy analysis. The study includes three levels of energy......It is well recognized that in the long run, the implementation of energy efficiency measures is a more cost-optimal solution in contrast to taking no action. However, the Net ZEB concept raises a new issue: how far should we go with energy efficiency measures and when should we start to apply...

  8. A Game Theoretic Framework for Green HetNets Using D2D Traffic Offload and Renewable Energy Powered Base Stations

    KAUST Repository

    Yaacoub, Elias

    2015-08-26

    This chapter investigates the interplay between cooperative device-to-device (D2D) communications and green communications in LTE heterogeneous networks (HetNets). Two game theoretic concepts are studied and analyzed in order to perform dynamic HetNet base station (BS) on/off switching. The first approach is a coalition-based method whereas the second is based on the Nash bargaining solution. Afterwards, a method for coupling the BS on/off switching approach with D2D collaborative communications is presented and shown to lead to increased energy efficiency. The savings are additionally increased when a portion of the small cell BSs in a HetNet are powered by renewable energy sources. Different utility functions, modeling the game theoretic framework governing the energy consumption balance between the cellular network and the mobile terminals (MTs), are proposed and compared, and their impact on MT quality of service (QoS) is analyzed.

  9. Mass and energy balance of the cold Io torus

    Science.gov (United States)

    Moreno, M. A.; Barbosa, D. D.

    1986-01-01

    A new model of the cold Io torus is described. Ions and energy are injected into the system by independent processes so that the mass balance is isolated from the energy balance. The primary source of energy is local ionization and acceleration of hot pickup ions resulting from charge exchange between thermal ions and an extended cloud of Iogenic sulfur and oxygen atoms. The primary energy loss mechanism of the plasma is collisionally excited line emission at optical wavelengths. The primary ion source is radial diffusion inward from the hot torus on a time scale of 140-710 days. The primary ion loss mechanism is a novel two-step enhanced recombination mechanism involving charge exchange between thermal ions and an extended cloud of neutral SO2 molecules, followed by rapid dissociative recombination of the resultant molecular ion. The model provides a self-consistent solution which reconciles a number of diverse observations with known physical processes.

  10. The global land surface energy balance and its representation in CMIP5 models

    Science.gov (United States)

    Wild, Martin; Folini, Doris; Hakuba, Maria; Schär, Christoph; Seneviratne, Sonia; Kato, Seiji; Rutan, David; Ammann, Christof; Wood, Eric; König-Langlo, Gert

    2015-04-01

    (ERA-Interim) and satellite-derived products (surface CERES EBAF). This remarkable consistency enhances confidence in the determined flux magnitudes, which so far caused large uncertainties in the energy budgets and often hampered an accurate simulation of surface climates in models. Using in addition a land mean surface albedo estimate of 0.26, we determine an average absorbed solar radiation at land surfaces of 136 Wm-2. Our best estimate for the upward thermal radiation at land surfaces (essentially based on the Stefan Boltzmann law) is 372 Wm-2, and combined with the above best estimate of 306 Wm-2 for the downward thermal radiation, this results in a net thermal radiation of -66 Wm-2 averaged over global land surfaces. Adding the absorbed solar and net thermal radiation, our best estimate of the land mean surface net radiation amounts to 70 Wm-2, which is the energy available for the sensible and latent heat fluxes. Latest estimates of terrestrial latent heat fluxes indicate a land mean value slightly below 40 Wm-2. In our best estimate of the global land mean energy balance we thus adopt a land mean latent heat flux of 38 Wm-2, leaving a land mean sensible heat flux of 32 Wm-2 as residual to close the energy balance over terrestrial surfaces. A diagram of the global land mean energy balance including these new estimates and the related discussion has recently been published in Climate Dynamics (Wild et al. 2015). Related reference: Wild, M., Folini, D., Hakuba, M., Schär, C., Seneviratne, S.I., Kato, S., Rutan, D., Ammann, C., Wood E.F. ·and König-Langlo, G., 2015: The energy balance over land and oceans: An assessment based on direct observations and CMIP5 climate models, Climate Dynamics, DOI 10.1007/s00382-014-2430-z

  11. Army Net Zero: Energy Roadmap and Program Summary, Fiscal Year 2013 (Brochure)

    Energy Technology Data Exchange (ETDEWEB)

    2014-08-01

    The U.S. Army (Army) partnered with the National Renewable Energy Laboratory (NREL) and the U.S. Army Corps of Engineers to assess opportunities for increasing energy security through improved energy efficiency and optimized renewable energy strategies at nine installations across the Army's portfolio. Referred to as Net Zero Energy Installations (NZEIs), these projects demonstrate and validate energy efficiency and renewable energy technologies with approaches that can be replicated across DOD and other Federal agencies, setting the stage for broad market adoption. This report summarizes the results of the energy project roadmaps developed by NREL, shows the progress each installation could make in achieving Net Zero Energy by 2020, and presents lessons learned and unique challenges from each installation.

  12. Relationships between energy balance knowledge and the home environment.

    Science.gov (United States)

    Slater, Megan E; Sirard, John R; Laska, Melissa N; Pereira, Mark A; Lytle, Leslie A

    2011-04-01

    Certain aspects of the home environment as well as individuals' knowledge of energy balance are believed to be important correlates of various dietary and physical activity behaviors, but no known studies have examined potential relationships between these correlates. This study evaluated cross-sectional associations between characteristics of the home environment and energy balance knowledge among 349 youth/parent pairs recruited from the Minneapolis/St Paul, MN, metropolitan area from September 2006 to June 2007. Linear regression models adjusted for student grade and highest level of parental education were used to compare data from home food, physical activity, and media inventories (parent-reported) with energy balance knowledge scores from youth and parent questionnaires. Paired energy balance knowledge (average of youth and parent knowledge scores) was associated with all home food availability variables. Paired knowledge was also significantly associated with a media equipment availability and accessibility summary score (β=-1.40, P=0.005), as well as an activity-to-media ratio score (β=0.72, P=0.003). Youth and/or parent knowledge alone was not significantly associated with most characteristics of the home environment, supporting the importance of developing intervention strategies that target the family as a whole. Copyright © 2011 American Dietetic Association. Published by Elsevier Inc. All rights reserved.

  13. Intergenerational Energy Balance Interventions: A Systematic Literature Review

    Science.gov (United States)

    Swanson, Mark; Studts, Christina R.; Bardach, Shoshana H.; Bersamin, Andrea; Schoenberg, Nancy E.

    2011-01-01

    Many nations have witnessed a dramatic increase in the prevalence of obesity and overweight across their population. Recognizing the influence of the household environment on energy balance has led many researchers to suggest that intergenerational interventions hold promise for addressing this epidemic. Yet few comprehensive reviews of…

  14. Montium - Balancing between Energy-Efficiency, Flexibility and Performance

    NARCIS (Netherlands)

    Heysters, P.M.; Smit, Gerardus Johannes Maria; Molenkamp, Egbert; Plaks, Toomas P.

    Architectures for mobile multimedia devices need to find a balance between energy-efficiency, flexibility and performance. In this paper it is reasoned that this can be accomplished by way of a System-on-Chip (SoC) that comprises heterogeneous processing tiles. This heterogeneous SoC calls for

  15. Seasonal changes in energy balance of rural Beninese women

    NARCIS (Netherlands)

    Schultink, J.W.

    1991-01-01

    This thesis reports on human energy balance in relation to seasonal changes in food availability of rural populations in developing countries.

    Body weight measurements were carried out every two weeks among Beninese subsistence farmers who live in two different climatological zones (one and

  16. Energy Balance Education in Schools: The Role of Student Knowledge

    Science.gov (United States)

    Chen, Senlin; Nam, Yoon Ho

    2017-01-01

    Obesity prevention and control have been identified as top public health priorities in modern societies. Sport and exercise science researchers from multiple perspectives (e.g. behavioral, pedagogical, psychological, and physiological) have been active contributors addressing this topic. This paper examines the importance of energy balance (EB)…

  17. Forecasting of renewable energy balance on Medium Term.

    OpenAIRE

    Dragomir, Otilia,; Dragomir, Florin; GOURIVEAU, Rafael; Minca, Eugénia

    2010-01-01

    International audience; The general purpose of the paper is to explore the way of performing renewable energy balance predictions prognostics so that energy market actors can act consequently. Different aspects of forecasting are discussed to point out pragmatic challenges of this approach. An illustration, with real monitored data, based on a neuro-fuzzy predictor is given. The architecture of the artificial intelligence technique used for forecasting is modified in order to obtain accurate ...

  18. Energy balance of Lower Saxony 1994; Niedersaechsische Energiebilanz 1994

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-10-01

    The energy balance of Lower Saxony is presented in physical units, in terrajoule and in coal equivalent to show supply, conversion, and consumption of primary and secondary energy sources in the year under report. (orig.) [Deutsch] Die Energiebilanz des Landes Niedersachsen in physikalischen Einheiten, in Terrajoule und in Steinkohleeinheiten stellt das Energieaufkommen, die Energieumwandlung und den Energieverbrauch fuer Primaer- und Sekundaerenergietraeger im Berichtsjahr dar. (orig.)

  19. Energy balance and obesity: what are the main drivers?

    Science.gov (United States)

    Romieu, Isabelle; Dossus, Laure; Barquera, Simón; Blottière, Hervé M; Franks, Paul W; Gunter, Marc; Hwalla, Nahla; Hursting, Stephen D; Leitzmann, Michael; Margetts, Barrie; Nishida, Chizuru; Potischman, Nancy; Seidell, Jacob; Stepien, Magdalena; Wang, Youfa; Westerterp, Klaas; Winichagoon, Pattanee; Wiseman, Martin; Willett, Walter C

    2017-03-01

    The aim of this paper is to review the evidence of the association between energy balance and obesity. In December 2015, the International Agency for Research on Cancer (IARC), Lyon, France convened a Working Group of international experts to review the evidence regarding energy balance and obesity, with a focus on Low and Middle Income Countries (LMIC). The global epidemic of obesity and the double burden, in LMICs, of malnutrition (coexistence of undernutrition and overnutrition) are both related to poor quality diet and unbalanced energy intake. Dietary patterns consistent with a traditional Mediterranean diet and other measures of diet quality can contribute to long-term weight control. Limiting consumption of sugar-sweetened beverages has a particularly important role in weight control. Genetic factors alone cannot explain the global epidemic of obesity. However, genetic, epigenetic factors and the microbiota could influence individual responses to diet and physical activity. Energy intake that exceeds energy expenditure is the main driver of weight gain. The quality of the diet may exert its effect on energy balance through complex hormonal and neurological pathways that influence satiety and possibly through other mechanisms. The food environment, marketing of unhealthy foods and urbanization, and reduction in sedentary behaviors and physical activity play important roles. Most of the evidence comes from High Income Countries and more research is needed in LMICs.

  20. Gut Hormones and Energy Balance, The Future for Obesity Therapy?

    Directory of Open Access Journals (Sweden)

    Anna Meiliana

    2009-12-01

    Full Text Available BACKGROUND: The prevalence of obesity is increasing in both developed and developing countries along with associated diseases such as type 2 diabetes and coronary heart disease. The recent discovery of a number of gut hormones that play a role in appetite regulation and are released or suppressed in response to a meal may offer new targets for the treatments of obesity. CONTENT: In addition to the obvious role of the gut in the digestion and absorption of nutrient, the intestine and associated visceral organs, including the pancreas, liver, and visceral adipose depots, have important sensing and signaling roles in the regulation of energy homeostatis. Signals reflecting energy stores, recent nutritional state, and other parameters are integrated in the central nervous system, particularly in the hypotalamus, to coordinate energy intake and expenditure. SUMMARY: Our understanding of the role of the gut in energy balance and insights into gut-derived signals will stimulate previously unexplored therapeutics for obesity and other disorders of energy balance. KEYWORDS: obesity, energy, balance, gut hormones, satiation, satiety.

  1. EcoVillage: A Net Zero Energy Ready Community

    Energy Technology Data Exchange (ETDEWEB)

    Arena, L. [Consortium for Advanced Residential Buildings, Norwalk, CT (United States); Faakye, O. [Consortium for Advanced Residential Buildings, Norwalk, CT (United States)

    2015-02-01

    CARB is working with the EcoVillage co-housing community in Ithaca, New York, on their third neighborhood called the Third Residential EcoVillage Experience (TREE). This community scale project consists of 40 housing units --15 apartments and 25 single family residences. The community is pursuing certifications for DOE Zero Energy Ready Home, U.S. Green Building Council Leadership in Energy and Environmental Design Gold, and ENERGY STAR for the entire project. Additionally, seven of the 25 homes, along with the four-story apartment building and community center, are being constructed to the Passive House (PH) design standard.

  2. Energy Balance of Friction and Friction Coefficient in Energetical Interpretation

    Directory of Open Access Journals (Sweden)

    S.V. Fedorov

    2015-09-01

    Full Text Available Sliding friction energy model is proposed. In this model, generalized mechanism of transformation and dissipation of energy under friction the model of elastic-plastic deformation and fracture contact volumes is considered. Energy model of the process of plastic deformation and destruction of solid bodies is based on the concept of ergodynamic of deformable bodies. Equations of energy balance of friction within the structural and energetic interpretation of deformation are proposed. The energy interpretation of the coefficient of friction is showed. From this position the friction coefficient is the most informative characteristic of the process. Experimental friction curves have been generalized. As a result of the energy analysis of friction, the energy diagram of the structural evolution of the friction surfaces is suggested.

  3. [Net energy analysis for annual 200 000 ton cassava ethanol production at Guangxi COFCO].

    Science.gov (United States)

    Yue, Guojun; Sun, Zhenjiang; Shen, Naidong

    2015-02-01

    Guangxi COFCO innovates its annual 200 000 ton cassava ethanol production in recent years. To evaluate the energy input/output of the production process, we used the domestic life cycle model. The calculation results show that the net energy value was 9.56 MJ/L ethanol. Energy input for ethanol production was 51.3% of the total. 61.5% of energy input for ethanol production was used for steam input in ethanol distillation. Energy produced from by-product was 5.03 MJ/L ethanol. Hence, efficient use of raw materials is an important measure to improve the energy efficiency in Guangxi COFCO and energy compensation from byproducts has key impact on the net energy saving.

  4. Mass and energy balances of sludge processing in reference and upgraded wastewater treatment plants.

    Science.gov (United States)

    Mininni, G; Laera, G; Bertanza, G; Canato, M; Sbrilli, A

    2015-05-01

    This paper describes the preliminary assessment of a platform of innovative upgrading solutions aimed at improving sludge management and resource recovery in wastewater treatment plants. The effectiveness of the upgrading solutions and the impacts of their integration in model reference plants have been evaluated by means of mass and energy balances on the whole treatment plant. Attention has been also paid to the fate of nitrogen and phosphorus in sludge processing and to their recycle back to the water line. Most of the upgrading options resulted in reduced production of dewatered sludge, which decreased from 45 to 56 g SS/(PE × day) in reference plants to 14-49 g SS/(PE × day) in the upgraded ones, with reduction up to 79% when wet oxidation was applied to the whole sludge production. The innovative upgrades generally entail an increased demand of electric energy from the grid, but energy recovery from biogas allowed to minimize the net energy consumption below 10 kWh/(PE × year) in the two most efficient solutions. In all other cases the net energy consumption was in the range of -11% and +28% of the reference scenarios.

  5. Obesity, Energy Balance and Cancer: New Opportunities for Prevention

    Science.gov (United States)

    Hursting, Stephen D.; DiGiovanni, John; Dannenberg, Andrew J.; Azrad, Maria; LeRoith, Derek; Demark-Wahnefried, Wendy; Kakarala, Madhuri; Brodie, Angela; Berger, Nathan A.

    2012-01-01

    Obesity is associated with increased risk and poor prognosis for many types of cancer. The mechanisms underlying the obesity-cancer link are becoming increasingly clear and provide multiple opportunities for primary to tertiary prevention. Several obesity-related host factors can influence tumor initiation, progression and/or response to therapy, and these have been implicated as key contributors to the complex effects of obesity on cancer incidence and outcomes. These host factors include insulin, insulin-like growth factor-1, leptin, adiponectin, steroid hormones, cytokines, and inflammation-related molecules. Each of these host factors is considered in the context of energy balance and as potential targets for cancer prevention. The possibility of prevention at the systems level, including energy restriction, dietary composition and exercise is considered as is the importance of the newly-emerging field of stem cell research as a model for studying energy balance and cancer prevention. PMID:23034147

  6. Obesity, energy balance, and cancer: new opportunities for prevention.

    Science.gov (United States)

    Hursting, Stephen D; Digiovanni, John; Dannenberg, Andrew J; Azrad, Maria; Leroith, Derek; Demark-Wahnefried, Wendy; Kakarala, Madhuri; Brodie, Angela; Berger, Nathan A

    2012-11-01

    Obesity is associated with increased risk and poor prognosis for many types of cancer. The mechanisms underlying the obesity-cancer link are becoming increasingly clear and provide multiple opportunities for primary to tertiary prevention. Several obesity-related host factors can influence tumor initiation, progression and/or response to therapy, and these have been implicated as key contributors to the complex effects of obesity on cancer incidence and outcomes. These host factors include insulin, insulin-like growth factor-I, leptin, adiponectin, steroid hormones, cytokines, and inflammation-related molecules. Each of these host factors is considered in the context of energy balance and as potential targets for cancer prevention. The possibility of prevention at the systems level, including energy restriction, dietary composition, and exercise is considered as is the importance of the newly emerging field of stem cell research as a model for studying energy balance and cancer prevention.

  7. Low protein diets produce divergent effects on energy balance

    Science.gov (United States)

    Pezeshki, Adel; Zapata, Rizaldy C.; Singh, Arashdeep; Yee, Nicholas J.; Chelikani, Prasanth K.

    2016-01-01

    Diets deficient in protein often increase food consumption, body weight and fat mass; however, the underlying mechanisms remain poorly understood. We compared the effects of diets varying in protein concentrations on energy balance in obesity-prone rats. We demonstrate that protein-free (0% protein calories) diets decreased energy intake and increased energy expenditure, very low protein (5% protein) diets increased energy intake and expenditure, whereas moderately low protein (10% protein) diets increased energy intake without altering expenditure, relative to control diet (15% protein). These diet-induced alterations in energy expenditure are in part mediated through enhanced serotonergic and β-adrenergic signaling coupled with upregulation of key thermogenic markers in brown fat and skeletal muscle. The protein-free and very low protein diets decreased plasma concentrations of multiple essential amino acids, anorexigenic and metabolic hormones, but these diets increased the tissue expression and plasma concentrations of fibroblast growth factor-21. Protein-free and very low protein diets induced fatty liver, reduced energy digestibility, and decreased lean mass and body weight that persisted beyond the restriction period. In contrast, moderately low protein diets promoted gain in body weight and adiposity following the period of protein restriction. Together, our findings demonstrate that low protein diets produce divergent effects on energy balance. PMID:27122299

  8. Low protein diets produce divergent effects on energy balance.

    Science.gov (United States)

    Pezeshki, Adel; Zapata, Rizaldy C; Singh, Arashdeep; Yee, Nicholas J; Chelikani, Prasanth K

    2016-04-28

    Diets deficient in protein often increase food consumption, body weight and fat mass; however, the underlying mechanisms remain poorly understood. We compared the effects of diets varying in protein concentrations on energy balance in obesity-prone rats. We demonstrate that protein-free (0% protein calories) diets decreased energy intake and increased energy expenditure, very low protein (5% protein) diets increased energy intake and expenditure, whereas moderately low protein (10% protein) diets increased energy intake without altering expenditure, relative to control diet (15% protein). These diet-induced alterations in energy expenditure are in part mediated through enhanced serotonergic and β-adrenergic signaling coupled with upregulation of key thermogenic markers in brown fat and skeletal muscle. The protein-free and very low protein diets decreased plasma concentrations of multiple essential amino acids, anorexigenic and metabolic hormones, but these diets increased the tissue expression and plasma concentrations of fibroblast growth factor-21. Protein-free and very low protein diets induced fatty liver, reduced energy digestibility, and decreased lean mass and body weight that persisted beyond the restriction period. In contrast, moderately low protein diets promoted gain in body weight and adiposity following the period of protein restriction. Together, our findings demonstrate that low protein diets produce divergent effects on energy balance.

  9. Bioenergy co-products derived from microalgae biomass via thermochemical conversion--life cycle energy balances and CO2 emissions.

    Science.gov (United States)

    Khoo, H H; Koh, C Y; Shaik, M S; Sharratt, P N

    2013-09-01

    An investigation of the potential to efficiently convert lipid-depleted residual microalgae biomass using thermochemical (gasification at 850 °C, pyrolysis at 550 °C, and torrefaction at 300 °C) processes to produce bioenergy derivatives was made. Energy indicators are established to account for the amount of energy inputs that have to be supplied to the system in order to gain 1 MJ of bio-energy output. The paper seeks to address the difference between net energy input-output balances based on a life cycle approach, from "cradle-to-bioenergy co-products", vs. thermochemical processes alone. The experimental results showed the lowest results of Net Energy Balances (NEB) to be 0.57 MJ/MJ bio-oil via pyrolysis, and highest, 6.48 MJ/MJ for gas derived via torrefaction. With the complete life cycle process chain factored in, the energy balances of NEBLCA increased to 1.67 MJ/MJ (bio-oil) and 7.01 MJ/MJ (gas). Energy efficiencies and the life cycle CO2 emissions were also calculated. Copyright © 2013 Elsevier Ltd. All rights reserved.

  10. Daily energy balance in children and adolescents. Does energy expenditure predict subsequent energy intake?

    Science.gov (United States)

    Thivel, David; Aucouturier, Julien; Doucet, Éric; Saunders, Travis J; Chaput, Jean-Philippe

    2013-01-01

    Both physical and sedentary activities primarily impact energy balance through energy expenditure, but they also have important implications in term of ingestive behavior. The literature provides scarce evidence on the relationship between daily activities and subsequent nutritional adaptations in children and adolescents. Sedentary activities and physical exercise are generally considered distinctly despite the fact that they represent the whole continuum of daily activity-induced energy expenditure. This brief review paper examines the impact of daily activities (from vigorous physical activity to imposed sedentary behaviors) on acute energy intake control of lean and obese children and adolescents, and whether energy expenditure is the main predictor of subsequent energy intake in this population. After an overview of the available literature, we conclude that both acute physical activity and sedentary behaviors induce food consumption modifications in children and adolescents but also that the important discrepancy between the methodologies used does not allow any clear conclusion so far. When considering energy intake responses according to the level of energy expenditure generated by those activities, it is clear that energy expenditure is not the main predictor of food consumption in both lean and obese children and adolescents. This suggests that other characteristics of those activities may have a greater impact on calorie intake (such as intensity, duration or induced mental stress) and that energy intake may be mainly determined by non-homeostatic pathways that could override the energetic and hormonal signals. Copyright © 2012 Elsevier Ltd. All rights reserved.

  11. Capsaicin increases sensation of fullness in energy balance, and decreases desire to eat after dinner in negative energy balance.

    Science.gov (United States)

    Janssens, Pilou L H R; Hursel, Rick; Westerterp-Plantenga, Margriet S

    2014-06-01

    Addition of capsaicin (CAPS) to the diet has been shown to increase satiety; therefore, CAPS is of interest for anti-obesity therapy. We investigated the effects of CAPS on appetite profile and ad libitum energy intake in relation to energy balance. Fifteen subjects (seven women and eight men, age: 29.7 ± 10.8yrs, BMI: 23.3 ± 2.9 kg/m(2)) underwent four conditions in a randomized crossover design in 36 hour sessions in a respiration chamber; they received 100% of their daily energy requirements in the conditions "100%Control" and "100%CAPS", and 75% of their daily energy requirements in the conditions "75%Control" and "75%CAPS", followed by an ad libitum dinner. In the 100%CAPS and 75%CAPS conditions, CAPS was given at a dose of 2.56 mg (1.03 g of red chili pepper, 39,050 Scoville heat units) with every meal. Satiety (P energy balance, addition of capsaicin to the diet increases satiety and fullness, and tends to prevent overeating when food intake is ad libitum. After dinner, capsaicin prevents the effects of the negative energy balance on desire to eat. Copyright © 2014. Published by Elsevier Ltd.

  12. Analyzing sectoral niche formation: The case of net-zero energy buildings in India

    NARCIS (Netherlands)

    Jain, Mansi; Hoppe, Thomas; Bressers, Johannes T.A.

    2017-01-01

    Large scale development of Net Zero Energy Buildings (NZEBs) is seen as a potential solution to deal with future energy challenges in the building sector. This article aims to assess the current status of NZEB development in India by using an integrated framework named Sectoral System Innovation

  13. Evaluation of Model Results and Measured Performance of Net-Zero Energy Homes in Hawaii: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Norton, P.; Kiatreungwattana, K.; Kelly, K. J.

    2013-03-01

    The Kaupuni community consists of 19 affordable net-zero energy homes that were built within the Waianae Valley of Oahu, Hawaii in 2011. The project was developed for the native Hawaiian community led by the Department of Hawaiian Homelands. This paper presents a comparison of the modeled and measured energy performance of the homes. Over the first year of occupancy, the community as a whole performed within 1% of the net-zero energy goals. The data show a range of performance from house to house with the majority of the homes consistently near or exceeding net-zero, while a few fall short of the predicted net-zero energy performance. The impact of building floor plan, weather, and cooling set point on this comparison is discussed. The project demonstrates the value of using building energy simulations as a tool to assist the project to achieve energy performance goals. Lessons learned from the energy performance monitoring has had immediate benefits in providing feedback to the homeowners, and will be used to influence future energy efficient designs in Hawaii and other tropical climates.

  14. An integrated model of soil-canopy spectral radiances, photosynthesis, fluorescence, temperature and energy balance

    Directory of Open Access Journals (Sweden)

    C. van der Tol

    2009-12-01

    Full Text Available This paper presents the model SCOPE (Soil Canopy Observation, Photochemistry and Energy fluxes, which is a vertical (1-D integrated radiative transfer and energy balance model. The model links visible to thermal infrared radiance spectra (0.4 to 50 μm as observed above the canopy to the fluxes of water, heat and carbon dioxide, as a function of vegetation structure, and the vertical profiles of temperature. Output of the model is the spectrum of outgoing radiation in the viewing direction and the turbulent heat fluxes, photosynthesis and chlorophyll fluorescence. A special routine is dedicated to the calculation of photosynthesis rate and chlorophyll fluorescence at the leaf level as a function of net radiation and leaf temperature. The fluorescence contributions from individual leaves are integrated over the canopy layer to calculate top-of-canopy fluorescence. The calculation of radiative transfer and the energy balance is fully integrated, allowing for feedback between leaf temperatures, leaf chlorophyll fluorescence and radiative fluxes. Leaf temperatures are calculated on the basis of energy balance closure. Model simulations were evaluated against observations reported in the literature and against data collected during field campaigns. These evaluations showed that SCOPE is able to reproduce realistic radiance spectra, directional radiance and energy balance fluxes. The model may be applied for the design of algorithms for the retrieval of evapotranspiration from optical and thermal earth observation data, for validation of existing methods to monitor vegetation functioning, to help interpret canopy fluorescence measurements, and to study the relationships between synoptic observations with diurnally integrated quantities. The model has been implemented in Matlab and has a modular design, thus allowing for great flexibility and scalability.

  15. The relevance of rooftops: Analyzing the microscale surface energy balance in the Chicago region

    Science.gov (United States)

    Khosla, Radhika

    Spatial structure in climate variables often exist over very short length scales within an urban area, and this structure is a result of various site-specific features. In order to analyze the seasonal and diurnal energy flows that take place at a microclimatic surface, this work develops a semi-empirical energy balance model. For this, radiation fluxes and meteorological measurements are determined by direct observation; sensible heat and latent heat fluxes by parameterizations; and the heat storage flux by a 1-D mechanistic model that allows analysis of the temperature profile and heat storage within an underlying slab. Two sites receive detailed study: an anthropogenic site, being a University of Chicago building rooftop, and a natural site, outside Chicago in the open country. Two identical sets of instruments record measurements contemporaneously from these locations during June-November 2007, the entire period for which analyses are carried out. The study yields seasonal trends in surface temperature, surface-to-air temperature contrast and net radiation. At both sites, a temporal hysteresis between net radiation and heat storage flux indicates that surplus energy absorbed during daylight is released to the atmosphere later in the evening. The surface energy balance model responds well to site specific features for both locations. An analysis of the surface energy balance shows that the flux of sensible heat is the largest non-radiative contributor to the roof's surface cooling, while the flux of latent heat (also referred to as evaporative cooling) is the largest heat sink for the soil layer. In the latter part of the study, the surface energy balance model is upgraded by adding the capability to compute changes in surface temperature and non-radiative fluxes for any specified set of thermal and reflective roof properties. The results of this analysis allow an examination of the relationship between the roof temperature, the heat flux entering the building

  16. Salt Marsh Net Ecosystem Carbon Balance: Improving Methods to Quantify the Role of Lateral (Tidal) Exchanges

    Science.gov (United States)

    Kroeger, K. D.

    2016-02-01

    Coastal wetlands are prime candidates for greenhouse gas emission offsets as they display extraordinarily high rates of carbon (C) sequestration. However, lack of data about rates of and controls on C sequestration in tidal wetlands, as well as substantial temporal and spatial heterogeneity, complicate development of both models and a methodology for use by C registries. The goals of our field research are to improve understanding of the climatic role of coastal wetlands, quantify potential for GHG emission offsets through restoration or preservation, and quantify impacts of eutrophication and other environmental factors. Among our objectives is to construct C and greenhouse gas (GHG) budgets for salt marshes, based on measurements of GHG exchanges with the atmosphere, C storage in soils, and lateral (tidal) exchanges of gases, C, and sediment. In this presentation, emphasis is on rate and source of tidal exchanges between salt marshes and adjacent estuaries. We measured fluxes by collecting high frequency data on tidal water flows and physical and chemical conditions in wetland channels using acoustic and optical sensors, as well as laser absorption spectrometry. To provide site-specific calibrations of sensors, we collected water samples across tidal cycles and seasons. Source investigations include analysis of stable isotope and lipid compositions. We used multiple regressions to estimate dissolved organic (DOC) and inorganic carbon (DIC) concentrations at high frequency over extended time. Carbon flux was calculated as the product of concentration and water flux, corrected for modeled flow outside of the tidal creek. Annual rates of net C flux from wetland to estuary indicate that both DOC and DIC are large terms in the salt marsh carbon budget relative to net exchange with the atmosphere and rate of storage in soil, and that DIC flux may have been underestimated in previous studies.

  17. How to Define Nearly Net Zero Energy Buildings nZEB

    DEFF Research Database (Denmark)

    Kurnitski, Jarek; Allard, Francis; Braham, Derrick

    2011-01-01

    Member States. The directive defines nearly zero energy buildings as a building that has a very high energy performance and requires the calculation of primary energy indicator. The nearly zero of very low amount of energy required should be covered to a very significant extent by energy from renewable...... sources, including energy from renewable sources produced on-site nearby. Based on the directive’s definition, nearly zero energy buildings is technically defined through the net zero energy building, which is a building using 0 kWh/(m2a) primary energy. Following the cost-optimality principle......This REHVA Task Force proposes a technical definition for nearly zero energy buildings required in the implementation of the Energy performance of buildings directive recast. Energy calculation framework and system boundaries associated with the definition are provided to specify which energy flows...

  18. Dissipation and energy balance in electronic dynamics of Na clusters

    Science.gov (United States)

    Vincendon, Marc; Suraud, Eric; Reinhard, Paul-Gerhard

    2017-06-01

    We investigate the impact of dissipation on the energy balance in the electron dynamics of metal clusters excited by strong electro-magnetic pulses. The dynamics is described theoretically by Time-Dependent Density-Functional Theory (TDDFT) at the level of Local Density Approximation (LDA) augmented by a self interaction correction term and a quantum collision term in Relaxation-Time Approximation (RTA). We evaluate the separate contributions to the total excitation energy, namely energy exported by electron emission, potential energy due to changing charge state, intrinsic kinetic and potential energy, and collective flow energy. The balance of these energies is studied as function of the laser parameters (frequency, intensity, pulse length) and as function of system size and charge. We also look at collisions with a highly charged ion and here at the dependence on the impact parameter (close versus distant collisions). Dissipation turns out to be small where direct electron emission prevails namely for laser frequencies above any ionization threshold and for slow electron extraction in distant collisions. Dissipation is large for fast collisions and at low laser frequencies, particularly at resonances. Contribution to the Topical Issue "Dynamics of Systems at the Nanoscale", edited by Andrey Solov'yov and Andrei Korol.

  19. The Influence of Output Variability from Renewable Electricity Generation on Net Energy Calculations

    Directory of Open Access Journals (Sweden)

    Hannes Kunz

    2014-01-01

    Full Text Available One key approach to analyzing the feasibility of energy extraction and generation technologies is to understand the net energy they contribute to society. These analyses most commonly focus on a simple comparison of a source’s expected energy outputs to the required energy inputs, measured in the form of energy return on investment (EROI. What is not typically factored into net energy analysis is the influence of output variability. This omission ignores a key attribute of biological organisms and societies alike: the preference for stable returns with low dispersion versus equivalent returns that are intermittent or variable. This biologic predilection for stability, observed and refined in academic financial literature, has a direct relationship to many new energy technologies whose outputs are much more variable than traditional energy sources. We investigate the impact of variability on net energy metrics and develop a theoretical framework to evaluate energy systems based on existing financial and biological risk models. We then illustrate the impact of variability on nominal energy return using representative technologies in electricity generation, with a more detailed analysis on wind power, where intermittence and stochastic availability of hard-to-store electricity will be factored into theoretical returns.

  20. Brain Ceramide Metabolism in the Control of Energy Balance

    Directory of Open Access Journals (Sweden)

    Céline Cruciani-Guglielmacci

    2017-10-01

    Full Text Available The regulation of energy balance by the central nervous system (CNS is a key actor of energy homeostasis in mammals, and deregulations of the fine mechanisms of nutrient sensing in the brain could lead to several metabolic diseases such as obesity and type 2 diabetes (T2D. Indeed, while neuronal activity primarily relies on glucose (lactate, pyruvate, the brain expresses at high level enzymes responsible for the transport, utilization and storage of lipids. It has been demonstrated that discrete neuronal networks in the hypothalamus have the ability to detect variation of circulating long chain fatty acids (FA to regulate food intake and peripheral glucose metabolism. During a chronic lipid excess situation, this physiological lipid sensing is impaired contributing to type 2 diabetes in predisposed subjects. Recently, different studies suggested that ceramides levels could be involved in the regulation of energy balance in both hypothalamic and extra-hypothalamic areas. Moreover, under lipotoxic conditions, these ceramides could play a role in the dysregulation of glucose homeostasis. In this review we aimed at describing the potential role of ceramides metabolism in the brain in the physiological and pathophysiological control of energy balance.

  1. Changes in the net carbon balance following a shelterwood harvest at Howland Forest in central Maine seven years after harvest

    Science.gov (United States)

    Scott, N. A.; Hollinger, D.; Davidson, E. A.; Rodrigues, C.; Hughes, H.; Lee, J. T.; Richardson, A. D.; Dail, B.

    2009-12-01

    a net C sink in 2005 and has remained a net C sink since that time. In 2007, the combination of C storage in live biomass and wood products put the net C balance at about 0.8 Mg C ha-1y-1. Our results demonstrate that rates of tree growth recovered rapidly after the harvest, returning the system to a net C sink within about four years after harvest. Further research will investigate the mechanisms behind the rapidly increasing tree growth rates after the harvest.

  2. Hypothalamic Inflammation and Energy Balance Disruptions: Spotlight on Chemokines

    Directory of Open Access Journals (Sweden)

    Ophélia Le Thuc

    2017-08-01

    Full Text Available The hypothalamus is a key brain region in the regulation of energy balance as it controls food intake and both energy storage and expenditure through integration of humoral, neural, and nutrient-related signals and cues. Many years of research have focused on the regulation of energy balance by hypothalamic neurons, but the most recent findings suggest that neurons and glial cells, such as microglia and astrocytes, in the hypothalamus actually orchestrate together several metabolic functions. Because glial cells have been described as mediators of inflammatory processes in the brain, the existence of a causal link between hypothalamic inflammation and the deregulations of feeding behavior, leading to involuntary weight loss or obesity for example, has been suggested. Several inflammatory pathways that could impair the hypothalamic control of energy balance have been studied over the years such as, among others, toll-like receptors and canonical cytokines. Yet, less studied so far, chemokines also represent interesting candidates that could link the aforementioned pathways and the activity of hypothalamic neurons. Indeed, chemokines, in addition to their role in attracting immune cells to the inflamed site, have been suggested to be capable of neuromodulation. Thus, they could disrupt cellular activity together with synthesis and/or secretion of multiple neurotransmitters/mediators involved in the maintenance of energy balance. This review discusses the different inflammatory pathways that have been identified so far in the hypothalamus in the context of feeding behavior and body weight control impairments, with a particular focus on chemokines signaling that opens a new avenue in the understanding of the major role played by inflammation in obesity.

  3. Hypothalamic Inflammation and Energy Balance Disruptions: Spotlight on Chemokines.

    Science.gov (United States)

    Le Thuc, Ophélia; Stobbe, Katharina; Cansell, Céline; Nahon, Jean-Louis; Blondeau, Nicolas; Rovère, Carole

    2017-01-01

    The hypothalamus is a key brain region in the regulation of energy balance as it controls food intake and both energy storage and expenditure through integration of humoral, neural, and nutrient-related signals and cues. Many years of research have focused on the regulation of energy balance by hypothalamic neurons, but the most recent findings suggest that neurons and glial cells, such as microglia and astrocytes, in the hypothalamus actually orchestrate together several metabolic functions. Because glial cells have been described as mediators of inflammatory processes in the brain, the existence of a causal link between hypothalamic inflammation and the deregulations of feeding behavior, leading to involuntary weight loss or obesity for example, has been suggested. Several inflammatory pathways that could impair the hypothalamic control of energy balance have been studied over the years such as, among others, toll-like receptors and canonical cytokines. Yet, less studied so far, chemokines also represent interesting candidates that could link the aforementioned pathways and the activity of hypothalamic neurons. Indeed, chemokines, in addition to their role in attracting immune cells to the inflamed site, have been suggested to be capable of neuromodulation. Thus, they could disrupt cellular activity together with synthesis and/or secretion of multiple neurotransmitters/mediators involved in the maintenance of energy balance. This review discusses the different inflammatory pathways that have been identified so far in the hypothalamus in the context of feeding behavior and body weight control impairments, with a particular focus on chemokines signaling that opens a new avenue in the understanding of the major role played by inflammation in obesity.

  4. Evaluating load balancing policies for performance and energy-efficiency

    Directory of Open Access Journals (Sweden)

    Freek van den Berg

    2016-10-01

    Full Text Available Nowadays, more and more increasingly hard computations are performed in challenging fields like weather forecasting, oil and gas exploration, and cryptanalysis. Many of such computations can be implemented using a computer cluster with a large number of servers. Incoming computation requests are then, via a so-called load balancing policy, distributed over the servers to ensure optimal performance. Additionally, being able to switch-off some servers during low period of workload, gives potential to reduced energy consumption. Therefore, load balancing forms, albeit indirectly, a trade-off between performance and energy consumption. In this paper, we introduce a syntax for load-balancing policies to dynamically select a server for each request based on relevant criteria, including the number of jobs queued in servers, power states of servers, and transition delays between power states of servers. To evaluate many policies, we implement two load balancers in: (i iDSL, a language and tool-chain for evaluating service-oriented systems, and (ii a simulation framework in AnyLogic. Both implementations are successfully validated by comparison of the results.

  5. Can an energy balance model provide additional constraints on how to close the energy imbalance?

    Science.gov (United States)

    Wohlfahrt, Georg; Widmoser, Peter

    2013-01-01

    Elucidating the causes for the energy imbalance, i.e. the phenomenon that eddy covariance latent and sensible heat fluxes fall short of available energy, is an outstanding problem in micrometeorology. This paper tests the hypothesis that the full energy balance, through incorporation of additional independent measurements which determine the driving forces of and resistances to energy transfer, provides further insights into the causes of the energy imbalance and additional constraints on energy balance closure options. Eddy covariance and auxiliary data from three different biomes were used to test five contrasting closure scenarios. The main result of our study is that except for nighttime, when fluxes were low and noisy, the full energy balance generally did not contain enough information to allow further insights into the causes of the imbalance and to constrain energy balance closure options. Up to four out of the five tested closure scenarios performed similarly and in up to 53% of all cases all of the tested closure scenarios resulted in plausible energy balance values. Our approach may though provide a sensible consistency check for eddy covariance energy flux measurements. PMID:24465072

  6. DOE Zero Energy Ready Home Case Study: One Sky Homes — Cottle Zero Net Energy Home, San Jose, CA

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2014-09-01

    This builder took home the Grand Winner prize in the Custom Builder category in the 2014 Housing Innovation Awards for its high performance building science approach. The builder used insulated concrete form blocks to create the insulated crawlspace foundation for its first DOE Zero Energy Ready Home, the first net zero energy new home certified in the state of California.

  7. Resiliency and medicine: how to create a positive energy balance.

    Science.gov (United States)

    Kelly, John D

    2011-01-01

    A career in orthopaedics is a race-a marathon. Many outside forces converge to increase stressors to high levels. Resiliency, or the ability to bounce back from difficulty, can be learned and nurtured. The management of energy, rather than time, holds the key to avoiding burnout. Orthopaedic surgeons must minimize "energy drain" by first recognizing their ability to become proactive and control their lives. Surgeons must learn how to say "no" and delegate work and responsibilities. A positive energy balance can be attained when relationships, not things, are given priority. A focus on passions and inspiration helps to maintain energy, while a connection to a "source" and living a morally just, service-oriented life will yield endless energy.

  8. Asymmetric warming significantly affects net primary production, but not ecosystem carbon balances of forest and grassland ecosystems in northern China.

    Science.gov (United States)

    Su, Hongxin; Feng, Jinchao; Axmacher, Jan C; Sang, Weiguo

    2015-03-13

    We combine the process-based ecosystem model (Biome-BGC) with climate change-scenarios based on both RegCM3 model outputs and historic observed trends to quantify differential effects of symmetric and asymmetric warming on ecosystem net primary productivity (NPP), heterotrophic respiration (Rh) and net ecosystem productivity (NEP) of six ecosystem types representing different climatic zones of northern China. Analysis of covariance shows that NPP is significant greater at most ecosystems under the various environmental change scenarios once temperature asymmetries are taken into consideration. However, these differences do not lead to significant differences in NEP, which indicates that asymmetry in climate change does not result in significant alterations of the overall carbon balance in the dominating forest or grassland ecosystems. Overall, NPP, Rh and NEP are regulated by highly interrelated effects of increases in temperature and atmospheric CO2 concentrations and precipitation changes, while the magnitude of these effects strongly varies across the six sites. Further studies underpinned by suitable experiments are nonetheless required to further improve the performance of ecosystem models and confirm the validity of these model predictions. This is crucial for a sound understanding of the mechanisms controlling the variability in asymmetric warming effects on ecosystem structure and functioning.

  9. Dynamic energy-balance model predicting gestational weight gain123

    Science.gov (United States)

    Thomas, Diana M; Navarro-Barrientos, Jesus E; Rivera, Daniel E; Heymsfield, Steven B; Bredlau, Carl; Redman, Leanne M; Martin, Corby K; Lederman, Sally A; M Collins, Linda; Butte, Nancy F

    2012-01-01

    Background: Gestational weight gains (GWGs) that exceed the 2009 Institute of Medicine recommended ranges increase risk of long-term postpartum weight retention; conversely, GWGs within the recommended ranges are more likely to result in positive maternal and fetal outcomes. Despite this evidence, recent epidemiologic studies have shown that the majority of pregnant women gain outside the target GWG ranges. A mathematical model that predicts GWG and energy intake could provide a clinical tool for setting precise goals during early pregnancy and continuous objective feedback throughout pregnancy. Objective: The purpose of this study was to develop and validate a differential equation model for energy balance during pregnancy that predicts GWG that results from changes in energy intakes. Design: A set of prepregnancy BMI–dependent mathematical models that predict GWG were developed by using data from a longitudinal study that measured gestational-changes in fat-free mass, fat mass, total body water, and total energy expenditure in 63 subjects. Results: Mathematical models developed for women with low, normal, and high prepregnancy BMI were shown to fit the original data. In 2 independent studies used for validation, model predictions of fat-free mass, fat mass, and total body water matched actual measurements within 1 kg. Conclusions: Our energy-balance model provides plausible predictions of GWG that results from changes in energy intakes. Because the model was implemented as a Web-based applet, it can be widely used by pregnant women and their health care providers. PMID:22170365

  10. A review of net metering mechanism for electricity renewable energy sources

    Energy Technology Data Exchange (ETDEWEB)

    Poullikkas, Andreas; Kourtis, George; Hadjipaschalis, Ioannis [Electricity Authority of Cyprus, P.O. Box 24506, 1399 Nicosia (Cyprus)

    2013-07-01

    In this work, an overview of the net metering mechanism for renewable energy sources for power generation (RES-E) systems is carried out. In particular, the net metering concept is examined with its benefits and misconceptions. Furthermore, a survey of the current operational net metering schemes in different countries in the world, such as, in Europe, USA, Canada, Thailand and Australia, is carried out. The survey indicated that there are different net metering mechanisms depending on the particularities of each country (or state in the case of USA). Especially, in Europe, only five countries are using net metering in a very simple form, such as, any amount of energy produced by the eligible RES-E technology is compensated from the energy consumed by the RES-E producer, which results to either a less overall electricity bill or to an exception in payment energy taxes. In the USA and the USA territories, any customer’s net excess generation is credited to the customer’s next electricity bill for a 12-month billing cycle at various rates or via a combination between rates. The actual type of net excess generation (NEG) credit is decided by a number of set criteria, such as the type of RES-E technology, the RES-E capacity limit, the type of customer and the type of utility. Regarding any excess credit at the end of the 12-month billing cycle, this is either granted to the utilities, or carries over indefinitely to the customer’s next electricity bill, or is reconciled annually at any rate, or provides an option to the customer to choose between the last two options.

  11. Energy Balance, Climate, and Life - Work of M. Budyko

    Science.gov (United States)

    Cahalan, Robert F.

    2004-01-01

    This talk will review the work of Mikhail I. Budyko, author of "Climate and Life" and many other works, who died recently at age 81, in St Petersburg, Russia. He directed the Division for Climate Change Research at the State Hydrological Institute. We will explore Budyko's work in clarifying the role of energy balance in determining planetary climate, and the role of climate in regulating Earth s biosphere.

  12. Battery model for electrical power system energy balance

    Science.gov (United States)

    Hafen, D. P.

    1983-01-01

    A model to simulate nickel-cadmium battery performance and response in a spacecraft electrical power system energy balance calculation was developed. The voltage of the battery is given as a function of temperature, operating depth-of-charge (DOD), and battery state-of-charge. Also accounted for is charge inefficiency. A battery is modeled by analysis of the results of a multiparameter battery cycling test at various temperatures and DOD's.

  13. Individual variation in the (patho)physiology of energy balance

    OpenAIRE

    Boersma, Gretha J.; Benthem, Lambertus; van Dijk, Gertjan; Scheurink, Anton J. W.

    2011-01-01

    There are large individual differences in the susceptibility for metabolic disorders such as obesity, the metabolic syndrome and type 2 diabetes. Unfortunately, most animal studies in this field ignore the importance of individual variation which limits the face validity of these studies for translation to the human situation. We have performed a series of studies that were particularly focused on the individual differences in the (patho)physiology of energy balance. The studies were performe...

  14. Net change in carbon emissions with increased wood energy use in the United States

    Science.gov (United States)

    Prakash Nepal; David N. Wear; Kenneth E. Skog

    2014-01-01

    Use of wood biomass for energy results in carbon (C) emissions at the time of burning and alters C stocks on the land because of harvest, regrowth, and changes in land use or management. This study evaluates the potential effects of expanded woody biomass energy use (for heat and power) on net C emissions over time. A scenario with increased wood energy use is compared...

  15. Demonstration of the Energy Component of the Installation Master Plan Using the Net Zero Energy Planner Tool: Cost and Performance Report

    Science.gov (United States)

    2015-12-11

    fossil fuel based energy to achieve a net zero fossil fuel energy status. Energy goals are achieved through synergy among energy use reduction in... fossil fuel based energy to achieve a net zero fossil fuel energy status. Energy goals will be achieved through synergy among energy use reduction in... fossil fuel use in new and renovated facilities by 2030 and to reduce overall facility energy usage by 30% by 2015 (EISA 2007).

  16. Brain lipoprotein lipase as a regulator of energy balance.

    Science.gov (United States)

    Cruciani-Guglielmacci, Céline; Magnan, Christophe

    2017-07-24

    The central nervous system is an essential actor in the control of the energy balance. Indeed, many signals of nervous (vagal afferent for example) or circulating (hormone, nutrients) origin converge towards the brain to inform it permanently of the energetic status of the organism. In turn, the brain sends information to the periphery (sympathetic vagal balance, thyroid or corticotropic axis) which allows a fine regulation of the energy fluxes by acting on the hepatic glucose production, the secretion of the pancreatic hormones (glucagon, insulin) or food behavior. Among the nutrients, increasing amount of data assigns a signal molecule role to lipids such as fatty acids. These fatty acids may originate from the bloodstream but may also be the product of the hydrolysis of lipoproteins such as chylomicrons or VLDLs. Indeed, the identification of lipoprotein lipase (LPL) in the brain has led to the hypothesis that the LPL-dependent degradation of TG-enriched particles, and the addition of fatty acids, as informative molecules, to sensitive cells (neurons and/or astrocytes), plays a key role in maintaining the energy balance at equilibrium. Other lipases could also participate in these regulatory mechanisms. This review will summarize the state of the art and open up perspectives. Copyright © 2017 Elsevier B.V. and Société Française de Biochimie et Biologie Moléculaire (SFBBM). All rights reserved.

  17. Energy saving in greenhouses can be obtained by energy balance-controlled screens

    Energy Technology Data Exchange (ETDEWEB)

    Andersson, N. E. (Univ. of Aarhus, Faculty of Agricultural Sciences, Dept. of Horticulture, Aarslev (Denmark)), e-mail: niels.andersson@agrsci.dk

    2011-03-15

    The energy screens in two greenhouses, one clad with double acrylic and one with single glass, were controlled by an energy balance model. The parameters in the model were heat transmission coefficients, air temperature in the greenhouse and outdoors, irradiance and a single constant for the solar energy efficiency. The energy consumption, screen movements and daily light integral were compared with a glass greenhouse in which the energy screens were controlled by irradiance. In the greenhouse with light-controlled screens the set point for opening and closing of the screens was 5 Wm-2. The energy-saving screens controlled by the energy balance model opened later and closed earlier than in the greenhouse with light-controlled screens. When using the energy balance model the energy saving was 14% for the glass greenhouse and 41% for the double acrylic greenhouse compared with the glass greenhouse with light-controlled screens. The air temperature was on average similar in the three greenhouses, but when the screens were controlled by energy balance the daily light integral was approximately 10% lower and the number of hours the screens were closed was prolonged with 35% for the glass-covered greenhouse and 25% for the double acrylic-covered greenhouse compared with the greenhouse with light-controlled screens. Energy peaks in connection with operation of the screens were not reduced. During the experiment Begonia elatior, Dendranthema grandiflora (Chrysanthemum), Hedera helix, Helianthus annuus, Gerbera jamesonii and Kalanchoe blossfeldiana were grown in the greenhouses. There was a trend in prolongation of the production time when the plants were grown in the glass greenhouse with energy balance control of the screens. A lower number of flowers or inflorescences were observed for some of the plant species produced in the greenhouses with energy balance-controlled screens

  18. N/Z dependence of balance energy throughout the colliding geometries

    OpenAIRE

    Gautam, Sakshi; Puri, Rajeev K.

    2011-01-01

    We study the N/Z dependence of balance energy throughout the mass range for colliding geometry varying from central to peripheral ones. Our results indicate that balance energy decreases linearly with increase in N/Z ratio for all the masses throughout the colliding geometry range. Also, the N/Z dependence of balance energy is sensitive to symmetry energy.

  19. The effects of partial sleep deprivation on energy balance: a systematic review and meta-analysis.

    Science.gov (United States)

    Al Khatib, H K; Harding, S V; Darzi, J; Pot, G K

    2017-05-01

    It is unknown whether short sleep duration causatively contributes to weight gain. Studies investigating effects of partial sleep deprivation (PSD) on energy balance components report conflicting findings. Our objective was to conduct a systematic review and meta-analysis of human intervention studies assessing the effects of PSD on energy intake (EI) and energy expenditure (EE). EMBASE, Medline, Cochrane CENTRAL, Web of Science and Scopus were searched. Differences in EI and total EE following PSD compared with a control condition were generated using the inverse variance method with random-effects models. Secondary outcomes included macronutrient distribution and resting metabolic rate. Heterogeneity was quantified with the I(2)-statistic. Seventeen studies (n=496) were eligible for inclusion in the systematic review, and 11 studies (n=172) provided sufficient data to be included in meta-analyses. EI was significantly increased by 385 kcal (95% confidence interval: 252, 517; P<0.00001) following PSD compared with the control condition. We found no significant change in total EE or resting metabolic rate as a result of PSD. The observed increase in EI was accompanied by significantly higher fat and lower protein intakes, but no effect on carbohydrate intake. The pooled effects of the studies with extractable data indicated that PSD resulted in increased EI with no effect on EE, leading to a net positive energy balance, which in the long term may contribute to weight gain.

  20. Model Property Based Material Balance and Energy Conservation Analysis for Process Industry Energy Transfer Systems

    Directory of Open Access Journals (Sweden)

    Fumin Ma

    2015-10-01

    Full Text Available Conventional historical data based material and energy balance analyses are static and isolated computations. Such methods cannot embody the cross-coupling effect of energy flow, material flow and information flow in the process industry; furthermore, they cannot easily realize the effective evaluation and comparison of different energy transfer processes by alternating the model module. In this paper, a novel method for material balance and energy conservation analysis of process industry energy transfer system is developed based on model property. Firstly, a reconfigurable energy transfer process model, which is independent of energy types and energy-consuming equipment, is presented from the viewpoint of the cross-coupling effect of energy flow, material flow and information flow. Thereafter the material balance determination is proposed based on both a dynamic incidence matrix and dynamic balance quantity. Moreover, the model-weighted conservation determination theorem is proved, and the energy efficiency analysis method is also discussed. Results confirmed the efficacy of the proposed methods, confirming its potential for use by process industry in energy efficiency analyses.

  1. The consequences of negative energy balance in anorexia syndrome.

    Science.gov (United States)

    Håglin, Lena

    2005-10-01

    Using four cases, this study describes common etiological factors and clinical sequelae in anorexia nervosa and athletic anorexia to present a biological explanation for interactions. Four anorectic girls were interviewed regarding their training programs and dietary intake. Bone mineral content, hormonal status, and energy intake were assessed during follow-ups. All the girls began training before puberty and had a low energy intake for age and height. Amenorrhea, low bone mineral content with stress fractures in three cases, and growth retardation in one case, were present at the follow-up after 6 years. Low amount of body fat and high serum cortisol is indicated and included in the discussion. The etiology is presented in an integrated model in addition to a biological explanation based on a negative energy balance, an acidic condition. Energy deficits during puberty can result in the clinical sequela of the anorexia syndrome.

  2. A novel electrochemical membrane bioreactor as a potential net energy producer for sustainable wastewater treatment.

    Science.gov (United States)

    Wang, Yun-Kun; Sheng, Guo-Ping; Shi, Bing-Jing; Li, Wen-Wei; Yu, Han-Qing

    2013-01-01

    One possible way to address both water and energy shortage issues, the two of major global challenges, is to recover energy and water resource from wastewater. Herein, a novel electrochemical membrane bioreactor (EMBR) was developed to recover energy from wastewater and meantime harvest clean water for reuse. With the help of the microorganisms in the biocatalysis and biodegradation process, net electricity could be recovered from a low-strength synthetic wastewater after estimating total energy consumption of this system. In addition, high-quality clean water was obtained for reuse. The results clearly demonstrate that, under the optimized operating conditions, it is possible to recover net energy from wastewater, while at the same time to harvest high-quality effluent for reuse with this novel wastewater treatment system.

  3. Final Technical Report - Autothermal Styrene Manufacturing Process with Net Export of Energy

    Energy Technology Data Exchange (ETDEWEB)

    Trubac, Robert , E.; Lin, Feng; Ghosh, Ruma: Greene, Marvin

    2011-11-29

    The overall objectives of the project were to: (a) develop an economically competitive processing technology for styrene monomer (SM) that would reduce process energy requirements by a minimum 25% relative to those of conventional technology while achieving a minimum 10% ROI; and (b) advance the technology towards commercial readiness. This technology is referred to as OMT (Oxymethylation of Toluene). The unique energy savings feature of the OMT technology would be replacement of the conventional benzene and ethylene feedstocks with toluene, methane in natural gas and air or oxygen, the latter of which have much lower specific energy of production values. As an oxidative technology, OMT is a net energy exporter rather than a net energy consumer like the conventional ethylbenzene/styrene (EB/SM) process. OMT plants would ultimately reduce the cost of styrene monomer which in turn will decrease the costs of polystyrene making it perhaps more cost competitive with competing polymers such as polypropylene.

  4. Using the balanced scorecard to characterize benefits of integration in the safety net.

    Science.gov (United States)

    Wells, Rebecca; Weiner, Bryan

    2005-05-01

    The purpose of this study was to develop a comprehensive framework depicting the potential benefits of integration among health-care providers that serve vulnerable populations. Research teams interviewed participants in 12 integrated functions across seven community health-centre-led networks. Functions included clinical processes; managed care contracting; and administrative services such as human resources, finance, and information systems. Using a Balanced Scorecard framework, benefits were identified across financial, customer, internal business, and learning and growth perspectives. Financial benefits were more frequently cited relative to managed care and administrative functions than relative to clinical functions. Clinical functions were frequently characterized by perceived improvements in patient care quality, while managed-care functions appeared to yield most benefits in access. Administrative functions were most often associated with improvements in internal business operations. There were substantial findings in learning and growth across all three types of integration, in keeping with the early stages of the integrated functions in the study. Findings imply that integration among health-care providers yields a wide range of benefits, but not necessarily quickly or financial in nature.

  5. The global mean energy balance under cloud-free conditions

    Science.gov (United States)

    Wild, Martin; Hakuba, Maria; Folini, Dois; Ott, Patricia; Long, Charles

    2017-04-01

    är, C., Loeb, N., Dutton, E.G., and König-Langlo, G., 2013: The global energy balance from a surface perspective. Climate Dynamics, 40, 3107-3134. Wild, M., Folini, D., Hakuba, M., Schär, C., Seneviratne, S.I., Kato, S., Rutan, D., Ammann, C., Wood, E.F., and König-Langlo, G., 2015: The energy balance over land and oceans: An assessment based on direct observations and CMIP5 climate models, Climate Dynamics, 3393-3429, 44, DOI 10.1007/s00382-014-2430-z.

  6. Dietary energy balance modulates ovarian cancer progression and metastasis

    Science.gov (United States)

    Al-Wahab, Zaid; Tebbe, Calvin; Chhina, Jasdeep; Dar, Sajad A.; Morris, Robert T.; Ali-Fehmi, Rouba; Giri, Shailendra; Munkarah, Adnan R.; Rattan, Ramandeep

    2014-01-01

    A high energy balance, or caloric excess, accounts as a tumor promoting factor, while a negative energy balance via caloric restriction, has been shown to delay cancer progression. The effect of energy balance on ovarian cancer progression was investigated in an isogeneic immunocompetent mouse model of epithelial ovarian cancer kept on a regimen of regular diet, high energy diet (HED) and calorie restricted diet (CRD), prior to inoculating the animals intraperitoneally with the mouse ovarian surface epithelial ID8 cancer cells. Tumor evaluation revealed that mice group on HED displayed the most extensive tumor formation with the highest tumor score at all organ sites (diaphragm, peritoneum, bowel, liver, kidney, spleen), accompanied with increased levels of insulin, leptin, insulin growth factor-1 (IGF-1), monocyte chemoattractant protein-1 (MCP-1), VEGF and interleukin 6 (IL-6). On the other hand, the mice group on CRD exhibited the least tumor burden associated with a significant reduction in levels of insulin, IGF-1, leptin, MCP-1, VEGF and IL-6. Immunohistochemistry analysis of tumors from HED mice showed higher activation of Akt and mTOR with decreased adenosine monophosphate activated kinase (AMPK) and SIRT1 activation, while tumors from the CRD group exhibited the reverse profile. In conclusion, ovarian cancer growth and metastasis occurred more aggressively under HED conditions and was significantly curtailed under CRD. The suggested mechanism involves modulated secretion of growth factors, cytokines and altered regulation of AMPK and SIRT1 that converges on mTOR inhibition. While the role of a high energy state in ovarian cancer has not been confirnmed in the literature, the current findings support investigating the potential impact of diet modulation as adjunct to other anticancer therapies and as possible individualized treatment strategy of epithelial ovarian cancer. PMID:25026276

  7. Appetite control and energy balance: impact of exercise.

    Science.gov (United States)

    Blundell, J E; Gibbons, C; Caudwell, P; Finlayson, G; Hopkins, M

    2015-02-01

    Exercise is widely regarded as one of the most valuable components of behaviour that can influence body weight and therefore help in the prevention and management of obesity. Indeed, long-term controlled trials show a clear dose-related effect of exercise on body weight. However, there is a suspicion, particularly fuelled by media reports, that exercise serves to increase hunger and drive up food intake thereby nullifying the energy expended through activity. Not everyone performing regular exercise will lose weight and several investigations have demonstrated a huge individual variability in the response to exercise regimes. What accounts for this heterogeneous response? First, exercise (or physical activity) through the expenditure of energy will influence the energy balance equation with the potential to generate an energy deficit. However, energy expenditure also influences the control of appetite (i.e. the physiological and psychological regulatory processes underpinning feeding) and energy intake. This dynamic interaction means that the prediction of a resultant shift in energy balance, and therefore weight change, will be complicated. In changing energy intake, exercise will impact on the biological mechanisms controlling appetite. It is becoming recognized that the major influences on the expression of appetite arise from fat-free mass and fat mass, resting metabolic rate, gastric adjustment to ingested food, changes in episodic peptides including insulin, ghrelin, cholecystokinin, glucagon-like peptide-1 and tyrosine-tyrosine, as well as tonic peptides such as leptin. Moreover, there is evidence that exercise will influence all of these components that, in turn, will influence the drive to eat through the modulation of hunger (a conscious sensation reflecting a mental urge to eat) and adjustments in postprandial satiety via an interaction with food composition. The specific actions of exercise on each physiological component will vary in strength from

  8. Supplementing an energy adequate, higher protein diet with protein does not enhance fat-free mass restoration after short-term severe negative energy balance.

    Science.gov (United States)

    Berryman, C E; Sepowitz, J J; McClung, H L; Lieberman, H R; Farina, E K; McClung, J P; Ferrando, A A; Pasiakos, S M

    2017-06-01

    Negative energy balance during military operations can be severe and result in significant reductions in fat-free mass (FFM). Consuming supplemental high-quality protein following such military operations may accelerate restoration of FFM. Body composition (dual-energy X-ray absorptiometry) and whole body protein turnover (single-pool [(15)N]alanine method) were determined before (PRE) and after 7 days (POST) of severe negative energy balance during military training in 63 male US Marines (means ± SD, 25 ± 3 yr, 84 ± 9 kg). After POST measures were collected, volunteers were randomized to receive higher protein (HIGH: 1,103 kcal/day, 133 g protein/day), moderate protein (MOD: 974 kcal/day, 84 g protein/day), or carbohydrate-based low protein control (CON: 1,042 kcal/day, 7 g protein/day) supplements, in addition to a self-selected, ad libitum diet, for the 27-day intervention (REFED). Measurements were repeated POST-REFED. POST total body mass (TBM; -5.8 ± 1.0 kg, -7.0%), FFM (-3.1 ± 1.6 kg, -4.7%), and net protein balance (-1.7 ± 1.1 g protein·kg(-1)·day(-1)) were lower and proteolysis (1.1 ± 1.9 g protein·kg(-1)·day(-1)) was higher compared with PRE (P energy (4,498 ± 725 kcal/day). All volunteers, independent of group assignment, achieved positive net protein balance (0.4 ± 1.0 g protein·kg(-1)·day(-1)) and gained TBM (5.9 ± 1.7 kg, 7.8%) and FFM (3.6 ± 1.8 kg, 5.7%) POST-REFED compared with POST (P energy-adequate, higher protein diets with additional protein may not be necessary to restore FFM after short-term severe negative energy balance.NEW & NOTEWORTHY This article demonstrates 1) the majority of physiological decrements incurred during military training (e.g., total and fat-free mass loss), with the exception of net protein balance, resolve and return to pretraining values after 27 days and 2) protein supplementation, in addition to an ad libitum, higher protein (~2.0 g·kg(-1)·day(-1)), energy adequate diet, is not necessary to restore

  9. Influence of partial sleep deprivation on energy balance and insulin sensitivity in healthy women.

    Science.gov (United States)

    Bosy-Westphal, Anja; Hinrichs, Silvia; Jauch-Chara, Kamila; Hitze, Britta; Later, Wiebke; Wilms, Britta; Settler, Uta; Peters, Achim; Kiosz, Dieter; Muller, Manfred James

    2008-01-01

    Voluntary sleep restriction is a lifestyle feature of modern societies that may contribute to obesity and diabetes. The aim of the study was to investigate the impact of partial sleep deprivation on the regulation of energy balance and insulin sensitivity. In a controlled intervention, 14 healthy women (age 23-38 years, BMI 20.0-36.6 kg/m(2)) were investigated after 2 nights of >8 h sleep/night (T0), after 4 nights of consecutively increasing sleep curtailment (7 h sleep/night, 6 h sleep/night, 6 h sleep/night and 4 h sleep/night; T1) and after 2 nights of sleep recovery (>8 h sleep/night; T2). Resting and total energy expenditure (REE, TEE), glucose-induced thermogenesis (GIT), physical activity, energy intake, glucose tolerance and endocrine parameters were assessed. After a decrease in sleep du-ration, energy intake (+20%), body weight (+0.4 kg), leptin/fat mass (+29%), free triiodothyronine (+19%), free thyroxine (+10%) and GIT (+34%) significantly increased (all p ghrelin levels remained unchanged at T1. The effect of sleep loss on GIT, fT3 and fT4 levels was inversely related to fat mass. Short-term sleep deprivation increased energy intake and led to a net weight gain in women. The effect of sleep restriction on energy expenditure needs to be specifically addressed in future studies using reference methods for total energy expenditure.

  10. Prediction Based Energy Balancing Forwarding in Cellular Networks

    Directory of Open Access Journals (Sweden)

    Yang Jian-Jun

    2017-01-01

    Full Text Available In the recent cellular network technologies, relay stations extend cell coverage and enhance signal strength for mobile users. However, busy traffic makes the relay stations in hot area run out of energy quickly. Energy is a very important factor in the forwarding of cellular network since mobile users(cell phones in hot cells often suffer from low throughput due to energy lack problems. In many situations, the energy lack problems take place because the energy loading is not balanced. In this paper, we present a prediction based forwarding algorithm to let a mobile node dynamically select the next relay station with highest potential energy capacity to resume communication. Key to this strategy is that a relay station only maintains three past status, and then it is able to predict the potential energy capacity. Then, the node selects the next hop with potential maximal energy. Moreover, a location based algorithm is developed to let the mobile node figure out the target region in order to avoid flooding. Simulations demonstrate that our approach significantly increase the aggregate throughput and decrease the delay in cellular network environment.

  11. Brain regulation of energy balance and body weight.

    Science.gov (United States)

    Rui, Liangyou

    2013-12-01

    Body weight is determined by a balance between food intake and energy expenditure. Multiple neural circuits in the brain have evolved to process information about food, food-related cues and food consumption to control feeding behavior. Numerous gastrointestinal endocrine cells produce and secrete satiety hormones in response to food consumption and digestion. These hormones suppress hunger and promote satiation and satiety mainly through hindbrain circuits, thus governing meal-by-meal eating behavior. In contrast, the hypothalamus integrates adiposity signals to regulate long-term energy balance and body weight. Distinct hypothalamic areas and various orexigenic and anorexigenic neurons have been identified to homeostatically regulate food intake. The hypothalamic circuits regulate food intake in part by modulating the sensitivity of the hindbrain to short-term satiety hormones. The hedonic and incentive properties of foods and food-related cues are processed by the corticolimbic reward circuits. The mesolimbic dopamine system encodes subjective "liking" and "wanting" of palatable foods, which is subjected to modulation by the hindbrain and the hypothalamic homeostatic circuits and by satiety and adiposity hormones. Satiety and adiposity hormones also promote energy expenditure by stimulating brown adipose tissue (BAT) activity. They stimulate BAT thermogenesis mainly by increasing the sympathetic outflow to BAT. Many defects in satiety and/or adiposity hormone signaling and in the hindbrain and the hypothalamic circuits have been described and are believed to contribute to the pathogenesis of energy imbalance and obesity.

  12. Dcf1 regulates neuropeptide expression and maintains energy balance.

    Science.gov (United States)

    Liu, Qiang; Chen, Yu; Li, Qian; Wu, Liang; Wen, Tieqiao

    2017-05-22

    Neuropeptide Y (NPY) is an important neurotransmitter in the brain that plays a pivotal role in food intake and energy storage. Although many studies have focused on these functions, the regulation of NPY expression remains unclear. Here we showed that dendritic cell factor 1 (Dcf1) regulates NPY expression and maintains energy balance. We found that NPY expression is significantly reduced in the hypothalamus of Dcf1 knockout (Dcf1-/-, KO) mice. In contrast, Dcf1 overexpression significantly increases NPY expression in the cell line. We also found that Dcf1 acts upstream of the NPY gene to regulate NPY expression and modulates the NPY-NPY receptor 1-GABA signal. Notably, we observed a significant increase in the ATP concentration in Dcf1-/- mice, suggesting a greater demand for energy in the absence of Dcf1. We studied the relationship between Dcf1 and NPY and revealed that Dcf1 plays a critical role in energy balance. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Essential role of UCP1 modulating the central effects of thyroid hormones on energy balance

    Directory of Open Access Journals (Sweden)

    Mayte Alvarez-Crespo

    2016-04-01

    Conclusions: We conclude that UCP1 is essential for mediation of the central effects of thyroid hormones on energy balance, and we suggest that similar UCP1-dependent effects may underlie central energy balance effects of other agents.

  14. Net ecosystem exchange and energy fluxes measured with the eddy covariance technique in a western Siberian bog

    Directory of Open Access Journals (Sweden)

    P. Alekseychik

    2017-08-01

    Full Text Available Very few studies of ecosystem–atmosphere exchange involving eddy covariance data have been conducted in Siberia, with none in the western Siberian middle taiga. This work provides the first estimates of carbon dioxide (CO2 and energy budgets in a typical bog of the western Siberian middle taiga based on May–August measurements in 2015. The footprint of measured fluxes consisted of a homogeneous mixture of tree-covered ridges and hollows with the vegetation represented by typical sedges and shrubs. Generally, the surface exchange rates resembled those of pine-covered bogs elsewhere. The surface energy balance closure approached 100 %. Net CO2 uptake was comparatively high, summing up to 202 gC m−2 for the four measurement months, while the Bowen ratio was seasonally stable at 28 %. The ecosystem turned into a net CO2 source during several front passage events in June and July. The periods of heavy rain helped keep the water table at a sustainably high level, preventing a usual drawdown in summer. However, because of the cloudy and rainy weather, the observed fluxes might rather represent the special weather conditions of 2015 than their typical magnitudes.

  15. A Net-Zero Energy Home Grows Up: Lessons and Puzzles from 10 Years of Data

    Energy Technology Data Exchange (ETDEWEB)

    Sparn, Bethany; Earle, Lieko; Christensen, Craig; Norton, Paul

    2016-08-26

    In 2005, Habitat for Humanity of Metro Denver, with support from NREL and other partners, built one of the first homes in the US to achieve net-zero energy based on monitored data. A family of three moved into the house when it was completed and lives there still. The home has been monitored continuously for the past ten years. Although PV production has remained steady, net energy performance has varied each year. The home was a net producer of energy annually in each of the first three years and in the ninth year, but not in years four through eight. Over the years, the PV system provided between 124% and 64% of the home source energy use. Electricity use in the home increased steadily during the first eight years, even though no significant new appliance was introduced into the house, such as a window air conditioner. Miscellaneous electric loads and space heating, both strongly dependent on occupant behavior, appear to be primarily responsible for the observed increase in energy use. An interesting aspect of this case study is how, even within a single family, natural changes in occupant lifestyles over time (e.g., kids growing up, schedules changing) can substantially impact the overall energy intensity of a home. Data from the last ten years will be explored for lessons learned that can improve the way we design low-load homes without sacrificing comfort or convenience for the occupants, and how we can make realistic predictions of long-term energy performance.

  16. Net-Zero Energy Home Grows Up: Lessons and Puzzles from 10 Years of Data; Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Sparn, Bethany; Earle, Lieko; Christensen, Craig; Norton, Paul

    2016-05-17

    In 2005, Habitat for Humanity of Metro Denver, with support from NREL and other partners, built one of the first homes in the US to achieve net-zero energy based on monitored data. A family of three moved into the house when it was completed and lives there still. The home has been monitored continuously for the past ten years. Although PV production has remained steady, net energy performance has varied each year. The home was a net producer of energy annually in each of the first three years and in the ninth year, but not in years four through eight. Over the years, the PV system provided between 124% and 64% of the home source energy use. Electricity use in the home increased steadily during the first eight years, even though no significant new appliance was introduced into the house, such as a window air conditioner. Miscellaneous electric loads and space heating, both strongly dependent on occupant behavior, appear to be primarily responsible for the observed increase in energy use. An interesting aspect of this case study is how, even within a single family, natural changes in occupant lifestyles over time (e.g., kids growing up, schedules changing) can substantially impact the overall energy intensity of a home. Data from the last ten years will be explored for lessons learned that can improve the way we design low-load homes without sacrificing comfort or convenience for the occupants, and how we can make realistic predictions of long-term energy performance.

  17. Description and evaluation of a net energy intake model as a function of dietary chewing index

    DEFF Research Database (Denmark)

    Jensen, L.M.; Markussen, B.; Nielsen, N.I.

    2016-01-01

    Previously, a linear relationship has been found between net energy intake (NEI) and dietary chewing index (CI) of the diet for different types of cattle. Therefore, we propose to generalize and calibrate this relationship into a new model for direct prediction of NEI by dairy cows from CI values...

  18. Monitoring the latent and sensible heat fluxes in vineyard by applying the energy balance model METRIC

    Directory of Open Access Journals (Sweden)

    J. González-Piqueras

    2015-06-01

    Full Text Available The monitoring of the energy fluxes over vineyard applying the one source energy balance model METRIC (Allen et al., 2007b are shown in this work. This model is considered operaive because it uses an internalized calibration method derived from the selection of two extreme pixels in the scene, from the minimum ET values such as the bare soil to a maximum that corresponds to full cover active vegetation. The model provides the maps of net radiation (Rn, soil heat flux (G, sensible heat (H, latent heat (LE, evapotranspiration (ET and crop coefficient (Kc. The flux values have been validated with a flux tower installed in the plot, providing a RMSE for instantaneous fluxes of 43 W m2, 33 W m2, 55 W m2 y 40 W m2 on Rn, G, H and LE. In relative terms are 8%, 29%, 21% and 20% respectively. The RMSE at daily scale for the ET is 0.58 mm day-1, with a value in the crop coefficient for the mid stage of 0.42±0.08. These results allow considering the model adequate for crop monitoring and irrigation purposes in vineyard. The values obtained have been compared to other studies over vineyard and with alternative energy balance models showing similar results.

  19. Energy Balance of a Typical U.S. Diet.

    Science.gov (United States)

    Alexandrou, Athanasios; Tenbergen, Klaus; Adhikari, Diganta

    2013-03-28

    Today's agriculture provides an ever increasing population with sufficient quantities of food. During food production, processing, handling and transportation, an amount of energy is invested into the various products. An energy analysis of a typical American diet provides policy makers, farmers and the public with the necessary information to evaluate and make informed decisions as to how to improve the efficient use of energy. At the same time, an informed consumer may become energy conscious and be able to make dietary choices based on food energy balance. This paper studies the energy sequestered in a typical American diet as defined in Food and Agriculture Organization of the United Nations, Statistics Division (FAOSTAT). The amount of energy incorporated in this diet of 3628 kcal (15.18 MJ) per person and day to produce, transport, handle and process the foods is calculated and found to have approximately 39.92 GJ (9.54 Gcal) sequestered per person and year. It is shown that a diet in line with the United States Department of Agriculture (USDA) recommendation of around 2100 kcal (8.79 MJ) per day person will result in a reduction of energy inputs by 42% on an annual basis. This reduction for the whole population of the United States of America (USA), corresponds to approximately 879 million barrels of oil equivalent (boe) savings. Energy efficiency for the food categories studied varies from 3.4% to 56.5% with an average of 21.7%. Food energy efficiency can be further improved in some food categories through either a reduction of energy inputs or yield increase.

  20. Comparison of Four Different Energy Balance Models for Estimating Evapotranspiration in the Midwestern United States

    OpenAIRE

    Singh, Ramesh K.; Senay, Gabriel B.

    2015-01-01

    The development of different energy balance models has allowed users to choose a model based on its suitability in a region. We compared four commonly used models—Mapping EvapoTranspiration at high Resolution with Internalized Calibration (METRIC) model, Surface Energy Balance Algorithm for Land (SEBAL) model, Surface Energy Balance System (SEBS) model, and the Operational Simplified Surface Energy Balance (SSEBop) model—using Landsat images to estimate evapotranspiration (ET) in the Midweste...

  1. Application of He’s Energy Balance Method to Duffing-Harmonic Oscillators

    DEFF Research Database (Denmark)

    Momeni, M.; Jamshidi, j.; Barari, Amin

    2011-01-01

    In this article, He's energy balance method is applied for calculating angular frequencies of nonlinear Duffing oscillators. This method offers a promising approach by constructing a Hamiltonian for the nonlinear oscillator. We illustrate that the energy balance is very effective and convenient...... and does not require linearization or small perturbation. Contrary to the conventional methods, in energy balance, only one iteration leads to high accuracy of the solutions. It is predicted that the energy balance method finds wide applications in engineering problems....

  2. Effect of pre-partum prilled fat supplementation on feed intake, energy balance and milk production in Murrah buffaloes.

    Science.gov (United States)

    Sharma, Shikha; Singh, Mahendra; Roy, Ashwani Kumar; Thakur, Sunita

    2016-03-01

    To investigate the effect of pre-partum prilled fat feeding on dry matter intake (DMI), energy balance and milk production in Murrah buffaloes. Advance pregnant Murrah buffaloes were either received a dietary supplement of prilled fat at 100 g/day for 35 days pre-partum and at 150 g/day for 95 days post-partum (supplemented group [SG]) or did not receive fat supplement (control group [CG]). DMI and the yields of milk and milk component were measured. A body condition score (BCS) was recorded. Energy balance and gross feed efficiency (GFE) were calculated. DMI and BCS were recorded and milk yield (MY), fat, protein, lactose, solid not fat, energy balance were measured. The fat corrected milk yield was calculated. The DMI was non-significant between groups and periods of study. BCS of buffaloes improved in the SG than CG (penergy intake in terms of total digestible nutrients (TDN%), TDN intake, digestible energy (DE), metabolizable energy/kg of milk, DE of milk, net energy, and GFE were higher (penergy balance and milk production in transition Murrah buffaloes.

  3. Multi-Ethnicity in the Malaysian Workplace: The Net Balance of 35 Years of Affirmative Policies as Observed by a Foreign Visitor

    Science.gov (United States)

    Montesino, Max U.

    2007-01-01

    This paper looks at the net societal balance of post-independence affirmative action policies in Malaysia. Social imbalances prompted the country to implement affirmative policies to uplift the majority natives (Malays, Indigenous people of Sabah and Sarawak, etc.). These policies were reluctantly accepted by the immigrant communities (Chinese,…

  4. Daily physical activity as determined by age, body mass and energy balance

    OpenAIRE

    Westerterp, Klaas R

    2015-01-01

    Aim Insight into the determinants of physical activity, including age, body mass and energy balance, facilitates the design of intervention studies with body mass and energy balance as determinants of health and optimal performance. Methods An analysis of physical activity energy expenditure in relation to age and body mass and in relation to energy balance, where activity energy expenditure is derived from daily energy expenditure as measured with doubly labelled water and body movement is m...

  5. Fuzzy droop control loops adjustment for stored energy balance in distributed energy storage system

    DEFF Research Database (Denmark)

    Aldana, Nelson Leonardo Diaz; Wu, Dan; Dragicevic, Tomislav

    2015-01-01

    system, in order to smooth the variations at the prime energy generator. In this paper, a decentralized strategy based on fuzzy logic is proposed in order to balance the state of charge of distributed energy storage systems in lowvoltage three phase AC microgrid. The proposed method weights the action...

  6. Dietary carbohydrates, components of energy balance, and associated health outcomes.

    Science.gov (United States)

    Smith, Harry A; Gonzalez, Javier T; Thompson, Dylan; Betts, James A

    2017-10-01

    The role of dietary carbohydrates in the development of obesity and associated metabolic dysfunction has recently been questioned. Within the last decade, the Scientific Advisory Committee on Nutrition carried out a comprehensive evaluation of the role of dietary carbohydrates in human health. The current review aims to complement and extend this report by providing specific consideration of the effects of the component parts of energy balance, their interactions, and their culmination on energy storage and health. PubMed was searched for all published trials that had a minimum follow-up period of 3 months and were designed to manipulate dietary carbohydrate intake, irrespective of resultant differences in absolute carbohydrate dose (grams per day). Dietary carbohydrate manipulation has little effect on the individual components of energy balance that have been assessed. However, the role of dietary carbohydrates in influencing physical activity has yet to be assessed using gold-standard measurement tools. Moreover, adherence to a diet of modified carbohydrate content has not been found to result in a consistent pattern of changes in weight or indirect measures of metabolic health. However, certain markers of cardiovascular disease risk (ie, blood triglycerides and high-density lipoprotein cholesterol) may respond positively to a reduction in dietary carbohydrates. © The Author(s) 2017. Published by Oxford University Press on behalf of the International Life Sciences Institute. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  7. Primary cilia in energy balance signaling and metabolic disorder.

    Science.gov (United States)

    Lee, Hankyu; Song, Jieun; Jung, Joo Hyun; Ko, Hyuk Wan

    2015-12-01

    Energy homeostasis in our body system is maintained by balancing the intake and expenditure of energy. Excessive accumulation of fat by disrupting the balance system causes overweight and obesity, which are increasingly becoming global health concerns. Understanding the pathogenesis of obesity focused on studying the genes related to familial types of obesity. Recently, a rare human genetic disorder, ciliopathy, links the role for genes regulating structure and function of a cellular organelle, the primary cilium, to metabolic disorder, obesity and type II diabetes. Primary cilia are microtubule based hair-like membranous structures, lacking motility and functions such as sensing the environmental cues, and transducing extracellular signals within the cells. Interestingly, the subclass of ciliopathies, such as Bardet-Biedle and Alström syndrome, manifest obesity and type II diabetes in human and mouse model systems. Moreover, studies on genetic mouse model system indicate that more ciliary genes affect energy homeostasis through multiple regulatory steps such as central and peripheral actions of leptin and insulin. In this review, we discuss the latest findings in primary cilia and metabolic disorders, and propose the possible interaction between primary cilia and the leptin and insulin signal pathways which might enhance our understanding of the unambiguous link of a cell's antenna to obesity and type II diabetes.

  8. Assessing the impacts of changes in treatment technology on energy and greenhouse gas balances for organic waste and wastewater treatment using historical data

    DEFF Research Database (Denmark)

    Hansen, Jens Aage; Poulsen, Tjalfe

    2009-01-01

    production from the remaining organic municipal waste. Wastewater treatment has changed from direct discharge of untreated wastewater to full organic matter and nutrient (N, P) removal combined with anaerobic digestion of the sludge for biogas production with power and heat generation. These changes......Historical data on organic waste and wastewater treatment during the period of 1970ĝ€"2020 were used to assess the impact of treatment on energy and greenhouse gas (GHG) balances. The assessment included the waste fractions: Sewage sludge, food waste, yard waste and other organic waste (paper...... in treatment technology have resulted in the waste and wastewater treatment systems in Aalborg progressing from being net consumers of energy and net emitters of GHG, to becoming net producers of energy and net savers of GHG emissions (due to substitution of fossil fuels elsewhere). If it is assumed...

  9. Amylin-mediated control of glycemia, energy balance, and cognition.

    Science.gov (United States)

    Mietlicki-Baase, Elizabeth G

    2016-08-01

    Amylin, a peptide hormone produced in the pancreas and in the brain, has well-established physiological roles in glycemic regulation and energy balance control. It improves postprandial blood glucose levels by suppressing gastric emptying and glucagon secretion; these beneficial effects have led to the FDA-approved use of the amylin analog pramlintide in the treatment of diabetes mellitus. Amylin also acts centrally as a satiation signal, reducing food intake and body weight. The ability of amylin to promote negative energy balance, along with its unique capacity to cooperatively facilitate or enhance the intake- and body weight-suppressive effects of other neuroendocrine signals like leptin, have made amylin a leading target for the development of novel pharmacotherapies for the treatment of obesity. In addition to these more widely studied effects, a growing body of literature suggests that amylin may play a role in processes related to cognition, including the neurodegeneration and cognitive deficits associated with Alzheimer's disease (AD). Although the function of amylin in AD is still unclear, intriguing recent reports indicate that amylin may improve cognitive ability and reduce hallmarks of neurodegeneration in the brain. The frequent comorbidity of diabetes mellitus and obesity, as well as the increased risk for and occurrence of AD associated with these metabolic diseases, suggests that amylin-based pharmaceutical strategies may provide multiple therapeutic benefits. This review will discuss the known effects of amylin on glycemic regulation, energy balance control, and cognitive/motivational processes. Particular focus will be devoted to the current and/or potential future clinical use of amylin pharmacotherapies for the treatment of diseases in each of these realms. Copyright © 2016 Elsevier Inc. All rights reserved.

  10. THERMAL COMFORT ZONES FORSTEADY-STATE ENERGY BALANCE MODEL

    Directory of Open Access Journals (Sweden)

    Ömer KAYNAKLI

    2003-01-01

    Full Text Available In this study, the various thermal comfort parameters including temperature, relative humidity, air velocity, metabolic activity and clothing resistance and their effect to each other are examined. The heat transfer equations given for steady state energy balance between body and environment and the empirical equations which give thermal comfort and physiological control mechanisms of body are used. According to the ASHRAE Standard 55-1992, an environment can be assumed comfortable while Predicted Percentage of Dissatisfied (PPD is less than % 10. Considering this, thermal comfort zones in various conditions are studied and results are presented and discussed

  11. Hypothalamic miRNAs: emerging roles in energy balance control.

    Science.gov (United States)

    Schneeberger, Marc; Gomez-Valadés, Alicia G; Ramirez, Sara; Gomis, Ramon; Claret, Marc

    2015-01-01

    The hypothalamus is a crucial central nervous system area controlling appetite, body weight and metabolism. It consists in multiple neuronal types that sense, integrate and generate appropriate responses to hormonal and nutritional signals partly by fine-tuning the expression of specific batteries of genes. However, the mechanisms regulating these neuronal gene programmes in physiology and pathophysiology are not completely understood. MicroRNAs (miRNAs) are key regulators of gene expression that recently emerged as pivotal modulators of systemic metabolism. In this article we will review current evidence indicating that miRNAs in hypothalamic neurons are also implicated in appetite and whole-body energy balance control.

  12. Hypothalamic miRNAs: emerging roles in energy balance control

    Directory of Open Access Journals (Sweden)

    Marc eSchneeberger

    2015-02-01

    Full Text Available The hypothalamus is a crucial central nervous system area controlling appetite, body weight and metabolism. It consists in multiple neuronal types that sense, integrate and generate appropriate responses to hormonal and nutritional signals partly by fine-tuning the expression of specific batteries of genes. However, the mechanisms regulating these neuronal gene programmes in physiology and pathophysiology are not completely understood. MicroRNAs (miRNAs are key regulators of gene expression that recently emerged as pivotal modulators of systemic metabolism. In this article we will review current evidence indicating that miRNAs in hypothalamic neurons are also implicated in appetite and whole-body energy balance control.

  13. Arctic melt ponds and energy balance in the climate system

    Science.gov (United States)

    Sudakov, Ivan

    2017-02-01

    Elements of Earth's cryosphere, such as the summer Arctic sea ice pack, are melting at precipitous rates that have far outpaced the projections of large scale climate models. Understanding key processes, such as the evolution of melt ponds that form atop Arctic sea ice and control its optical properties, is crucial to improving climate projections. These types of critical phenomena in the cryosphere are of increasing interest as the climate system warms, and are crucial for predicting its stability. In this paper, we consider how geometrical properties of melt ponds can influence ice-albedo feedback and how it can influence the equilibria in the energy balance of the planet.

  14. Reproduction and energy balance: the integrative role of prolactin

    Directory of Open Access Journals (Sweden)

    T I Romantsova

    2014-03-01

    Full Text Available The physiological mechanisms controlling reproduction are closely linked to energy balance. In the recent years, accumulating evidence suggests that prolactin regulates metabolic functions, besides regulating breast development and stimulating milk formation. Hyperprolactinemia is associated with obesity and treatment with dopamine agonists results in weight loss. We discuss the integrated effects of prolactin in the metabolic control and reproductive function, the role of prolactin in the pathogenesis of obesity. The present review also describes the effects of treatment with cabergoline on body weight and cardiovascular risk markers.

  15. Mass and energy balance in the 1973 August 9 flare

    Science.gov (United States)

    Dere, K. P.; Cook, J. W.

    1983-01-01

    The mass and energy balance of the thermal plasma during the decay phase of the solar flare of August 9, 1973, are studied. The analysis is based on observationally determined values for the differential emission measure, density, turbulent and bulk velocities, and physical dimensions. The total particle content and total thermal energy content of the flare plasmas with temperatures above 100,000 K and their variation with time are calculated. The particle loss and the energy losses through radiation, conduction, and convection are evaluated. The decrease in total particle content can be accounted for by the convective losses through the loop footprints at 100,000 K. Radiation is the dominant energy loss mechanism although convective losses at 100,000 K can be important. Conductive losses at 100,000 K into cooler chromospheric material appear to be negligible. The decrease in the total energy content during the decay phase is equal to the sum of the energy losses over the period of observation. No requirement is found for continued heating during the decay phase.

  16. Acute effects of capsaicin on energy expenditure and fat oxidation in negative energy balance.

    Science.gov (United States)

    Janssens, Pilou L H R; Hursel, Rick; Martens, Eveline A P; Westerterp-Plantenga, Margriet S

    2013-01-01

    Addition of capsaicin (CAPS) to the diet has been shown to increase energy expenditure; therefore capsaicin is an interesting target for anti-obesity therapy. We investigated the 24 h effects of CAPS on energy expenditure, substrate oxidation and blood pressure during 25% negative energy balance. Subjects underwent four 36 h sessions in a respiration chamber for measurements of energy expenditure, substrate oxidation and blood pressure. They received 100% or 75% of their daily energy requirements in the conditions '100%CAPS', '100%Control', '75%CAPS' and '75%Control'. CAPS was given at a dose of 2.56 mg (1.03 g of red chili pepper, 39,050 Scoville heat units (SHU)) with every meal. An induced negative energy balance of 25% was effectively a 20.5% negative energy balance due to adapting mechanisms. Diet-induced thermogenesis (DIT) and resting energy expenditure (REE) at 75%CAPS did not differ from DIT and REE at 100%Control, while at 75%Control these tended to be or were lower than at 100%Control (p = 0.05 and p = 0.02 respectively). Sleeping metabolic rate (SMR) at 75%CAPS did not differ from SMR at 100%CAPS, while SMR at 75%Control was lower than at 100%CAPS (p = 0.04). Fat oxidation at 75%CAPS was higher than at 100%Control (p = 0.03), while with 75%Control it did not differ from 100%Control. Respiratory quotient (RQ) was more decreased at 75%CAPS (p = 0.04) than at 75%Control (p = 0.05) when compared with 100%Control. Blood pressure did not differ between the four conditions. In an effectively 20.5% negative energy balance, consumption of 2.56 mg capsaicin per meal supports negative energy balance by counteracting the unfavorable negative energy balance effect of decrease in components of energy expenditure. Moreover, consumption of 2.56 mg capsaicin per meal promotes fat oxidation in negative energy balance and does not increase blood pressure significantly. Nederlands Trial Register; registration number NTR2944.

  17. Acute effects of capsaicin on energy expenditure and fat oxidation in negative energy balance.

    Directory of Open Access Journals (Sweden)

    Pilou L H R Janssens

    Full Text Available BACKGROUND: Addition of capsaicin (CAPS to the diet has been shown to increase energy expenditure; therefore capsaicin is an interesting target for anti-obesity therapy. AIM: We investigated the 24 h effects of CAPS on energy expenditure, substrate oxidation and blood pressure during 25% negative energy balance. METHODS: Subjects underwent four 36 h sessions in a respiration chamber for measurements of energy expenditure, substrate oxidation and blood pressure. They received 100% or 75% of their daily energy requirements in the conditions '100%CAPS', '100%Control', '75%CAPS' and '75%Control'. CAPS was given at a dose of 2.56 mg (1.03 g of red chili pepper, 39,050 Scoville heat units (SHU with every meal. RESULTS: An induced negative energy balance of 25% was effectively a 20.5% negative energy balance due to adapting mechanisms. Diet-induced thermogenesis (DIT and resting energy expenditure (REE at 75%CAPS did not differ from DIT and REE at 100%Control, while at 75%Control these tended to be or were lower than at 100%Control (p = 0.05 and p = 0.02 respectively. Sleeping metabolic rate (SMR at 75%CAPS did not differ from SMR at 100%CAPS, while SMR at 75%Control was lower than at 100%CAPS (p = 0.04. Fat oxidation at 75%CAPS was higher than at 100%Control (p = 0.03, while with 75%Control it did not differ from 100%Control. Respiratory quotient (RQ was more decreased at 75%CAPS (p = 0.04 than at 75%Control (p = 0.05 when compared with 100%Control. Blood pressure did not differ between the four conditions. CONCLUSION: In an effectively 20.5% negative energy balance, consumption of 2.56 mg capsaicin per meal supports negative energy balance by counteracting the unfavorable negative energy balance effect of decrease in components of energy expenditure. Moreover, consumption of 2.56 mg capsaicin per meal promotes fat oxidation in negative energy balance and does not increase blood pressure significantly. TRIAL REGISTRATION

  18. Energy Storage System Based on Cascaded Multilevel Inverter with Decoupled Energy Balancing Control

    Directory of Open Access Journals (Sweden)

    Cao Yuanzhi

    2015-01-01

    Full Text Available This paper presents a three phase cascaded multilevel inverter based supercapacitor (SC energy storage system with novel structure and control strategy to maintain the energy balance of between phases. Every two phases are coupled with a series LC filter. With the filter, SC cells in different phases could exchange energy with an auxiliary power flow at high frequency. The auxiliary power flow is orthogonal to the primary power flow. The phase difference between high frequency voltage and current components of each phase determines whether the energy is absorbed into or released from its SC cells. Unlike traditional energy balancing strategies, the proposed method is independent to the fundamental real power drawn by the energy storage system. Simulation results confirmed the effects of proposed theories.

  19. Analysis of the snow-atmosphere energy balance during wet-snow instabilities and implications for avalanche prediction

    Directory of Open Access Journals (Sweden)

    C. Mitterer

    2013-02-01

    Full Text Available Wet-snow avalanches are notoriously difficult to predict; their formation mechanism is poorly understood since in situ measurements representing the thermal and mechanical evolution are difficult to perform. Instead, air temperature is commonly used as a predictor variable for days with high wet-snow avalanche danger – often with limited success. As melt water is a major driver of wet-snow instability and snow melt depends on the energy input into the snow cover, we computed the energy balance for predicting periods with high wet-snow avalanche activity. The energy balance was partly measured and partly modelled for virtual slopes at different elevations for the aspects south and north using the 1-D snow cover model SNOWPACK. We used measured meteorological variables and computed energy balance and its components to compare wet-snow avalanche days to non-avalanche days for four consecutive winter seasons in the surroundings of Davos, Switzerland. Air temperature, the net shortwave radiation and the energy input integrated over 3 or 5 days showed best results in discriminating event from non-event days. Multivariate statistics, however, revealed that for better predicting avalanche days, information on the cold content of the snowpack is necessary. Wet-snow avalanche activity was closely related to periods when large parts of the snowpack reached an isothermal state (0 °C and energy input exceeded a maximum value of 200 kJ m−2 in one day, or the 3-day sum of positive energy input was larger than 1.2 MJ m−2. Prediction accuracy with measured meteorological variables was as good as with computed energy balance parameters, but simulated energy balance variables accounted better for different aspects, slopes and elevations than meteorological data.

  20. Improving and validating 3D models for the leaf energy balance in canopy-scale problems with complex geometry

    Science.gov (United States)

    Bailey, B.; Stoll, R., II; Miller, N. E.; Pardyjak, E.; Mahaffee, W.

    2014-12-01

    Plants cover the majority of Earth's land surface, and thus play a critical role in the surface energy balance. Within individual plant communities, the leaf energy balance is a fundamental component of most biophysical processes. Absorbed radiation drives the energy balance and provides the means by which plants produce food. Available energy is partitioned into sensible and latent heat fluxes to determine surface temperature, which strongly influences rates of metabolic activity and growth. The energy balance of an individual leaf is coupled with other leaves in the community through longwave radiation emission and advection through the air. This complex coupling can make scaling models from leaves to whole-canopies difficult, specifically in canopies with complex, heterogeneous geometries. We present a new three-dimensional canopy model that simultaneously resolves sub-tree to whole-canopy scales. The model provides spatially explicit predictions of net radiation exchange, boundary-layer and stomatal conductances, evapotranspiration rates, and ultimately leaf surface temperature. The radiation model includes complex physics such as anisotropic emission and scattering. Radiation calculations are accelerated by leveraging graphics processing unit (GPU) technology, which allows canopy-scale problems to be performed on a standard desktop workstation. Since validating the three-dimensional distribution of leaf temperature can be extremely challenging, we used several independent measurement techniques to quantify errors in measured and modeled values. When compared with measured leaf temperatures, the model gave a mean error of about 2°C, which was close to the estimated measurement uncertainty.

  1. Examples of Nearly Net Zero Energy Buildings Through One-Step and Stepwise Retrofits

    DEFF Research Database (Denmark)

    Galiotto, Nicolas; Heiselberg, Per; Knudstrup, Mary-Ann

    2012-01-01

    -step or stepwise retrofit process. The review work is part of a more global Ph.D. project and is used as one of the basement of the future research work. The considered approaches have been sorted in two categories. The first approach has a very high use of energy conservation measures and low use of renewable...... energy production measures. The second approach has a lower use of energy conservation measures (but still high compared to a traditional renovation) and a higher use of renewable energy production measures. A third approach to nearly net zero energy building renovation exists but has not been considered......: a very low use of energy conservation measures and very high use of renewable energy production measures. While the projects from the first category have still a possibility to improve considerably their carbon footprint during an ulterior upgrade, the projects part of the second category seem to have...

  2. Genetic parameters of estimated net energy efficiencies for milk production, maintenance, and body weight change in dairy cows.

    Science.gov (United States)

    Buttazzoni, L; Mao, I L

    1989-03-01

    Net efficiencies of converting intake energy into energy for maintenance, milk production, and body weight change in a lactation were estimated for each of 79 Holstein cows by a two-stage multiple regression model. Cows were from 16 paternal half-sib families, which each had members in at least two of the six herds. Each cow was recorded for milk yield, net energy intake, and three efficiency traits. These were analyzed in a multitrait model containing the same 14 fixed subclasses of herd by season by parity and a random factor of sires for each of the five traits. Restricted maximum likelihood estimates of sire and residual (co)variance components were obtained by an expectation maximization algorithm with canonical transformations. Between milk yield and net energy intake, net energy efficiencies for milk yield, maintenance, and body weight change, the estimated phenotypic correlations were .36, -.02, .08, and -.06, while the genetic correlations were .92, .56, .02, and -.32, respectively. Both genetic and phenotypic correlations were zero between net energy efficiency of maintenance and that of milk yield and .17 between net energy efficiency of body weight change and that of milk yield. The estimated genetic correlation between net efficiency for lactation and milk yield is approximately 60% of that between gross efficiency and milk yield. With a heritability of .32 equivalent.49, net energy efficiency for milk yield may be worth consideration for genetic selection in certain dairy cattle populations.

  3. Mechanisms linking energy balance and reproduction: impact of prenatal environment.

    Science.gov (United States)

    Rhinehart, Erin M

    2016-01-01

    The burgeoning field of metabolic reproduction regulation has been gaining momentum due to highly frequent discoveries of new neuroendocrine factors regulating both energy balance and reproduction. Universally throughout the animal kingdom, energy deficits inhibit the reproductive axis, which demonstrates that reproduction is acutely sensitive to fuel availability. Entrainment of reproductive efforts with energy availability is especially critical for females because they expend large amounts of energy on gestation and lactation. Research has identified an assortment of both central and peripheral factors involved in the metabolic regulation of reproduction. From an evolutionary perspective, these mechanisms likely evolved to optimize reproductive fitness in an environment with an unpredictable food supply and regular bouts of famine. To be effective, however, the mechanisms responsible for the metabolic regulation of reproduction must also retain developmental plasticity to allow organisms to adapt their reproductive strategies to their particular niche. In particular, the prenatal environment has emerged as a critical developmental window for programming the mechanisms responsible for the metabolic control of reproduction. This review will discuss the current knowledge about hormonal and molecular mechanisms that entrain reproduction with prevailing energy availability. In addition, it will provide an evolutionary, human life-history framework to assist in the interpretation of findings on gestational programming of the female reproductive function, with a focus on pubertal timing as an example. Future research should aim to shed light on mechanisms underlying the prenatal modulation of the adaptation to an environment with unstable resources in a way that optimizes reproductive fitness.

  4. Water-Energy balance in pressure irrigation systems

    Science.gov (United States)

    Sánchez, Raúl; Rodríguez-Sinobas, Leonor; Juana, Luis; Laguna, Francisco V.; Castañón, Guillermo; Gil, María; Benitez, Javier

    2013-04-01

    Modernization of irrigation schemes, generally understood as transformation of surface irrigation systems into pressure -sprinkler and trickle- irrigation systems, aims at, among others, improving irrigation efficiency and reduction of operation and maintenance efforts made by the irrigators. Automation techniques become easier after modernization, and operation management plays an important role in energy efficiency issues. Modern systems use to include elevated water reservoirs with enough capacity to irrigate during peak water demand period about 16 to 48 h. However, pressure irrigation systems, in contrast, carry a serious energy cost. Energy requirements depend on decisions taken on management strategies during the operation phase, which are conditioned by previous decisions taken on the design project of the different elements which compose the irrigation system. Most of the countries where irrigation activity is significant bear in mind that modernization irrigation must play a key role in the agricultural infrastructure policies. The objective of this study is to characterize and estimate the mean and variation of the energy consumed by common types of irrigation systems according to their management possibilities. Also is an objective to estimate the fraction of the water reservoirs available along the irrigation campaign for storing the energy from renewable sources during their availability periods. Simulation taking into account all elements comprising the irrigation system has been used to estimate the energy requirements of typical irrigation systems of several crop production systems. The simulation of various types of irrigation systems and management strategies, in the framework imposed by particular cropping systems, would help to develop criteria for improving the energy balance in relation to the irrigation water supply productivity and new opportunities in the renewable energy field.

  5. Energy balance of forage consumption by phyllophagous insects: optimization model

    Directory of Open Access Journals (Sweden)

    O. V. Tarasova

    2015-06-01

    Full Text Available The model of optimal food consumption by phytophagous insects proposed, in which the metabolic costs are presented in the form of two components – the cost of food utilization and costs for proper metabolism of the individuals. Two measures were introduced – the «price» of food conversion and the «price» of biomass synthesis of individuals to assess the effectiveness of food consumption by caterpillars. The proposed approach to the description of food consumption by insects provides the exact solutions of the equation of energy balance of food consumption and determining the effectiveness of consumption and the risk of death of the individual. Experiments on larvae’s feeding in laboratory conditions were carried out to verify the model. Caterpillars of Aporia crataegi L. (Lepidoptera, Pieridae were the research subjects. Supply­demand balance, calculated value of the environmental price of consumption and efficiency of food consumption for each individual were determined from experimental data. It was found that the fertility of the female does not depend on the weight of food consumed by it, but is linearly dependent on the food consumption efficiency index. The greater the efficiency of food consumption by an individual, the higher its fertility. The data obtained in the course of experiments on the feeding caterpillars Aporia crataegi were compared with the data presented in the works of other authors and counted in the proposed model of consumption. Calculations allowed estimation of the critical value of food conversion price below which the energy balance is negative and the existence of an individual is not possible.

  6. The mass balance of the Greenland ice sheet: sensitivity to climate change as revealed by energy-balance modelling

    NARCIS (Netherlands)

    Oerlemans, J.

    1991-01-01

    The sensitivity of the mass balance of the Greenland ice sheet to climate change is studied with an energy-balance model of the ice/snow surface, applied at 200 m elevation intervals for four characteristic regions of the ice sheet. Solar radiation, longwave radiation, turbulent heat fluxes

  7. Mass and Energy Balances of Dry Thermophilic Anaerobic Digestion Treating Swine Manure Mixed with Rice Straw

    Directory of Open Access Journals (Sweden)

    Sheng Zhou

    2015-01-01

    Full Text Available To evaluate the feasibility of swine manure treatment by a proposed Dry Thermophilic Anaerobic Digestion (DT-AD system, we evaluated the methane yield of swine manure treated using a DT-AD method with rice straw under different C/N ratios and solid retention time (SRT and calculated the mass and energy balances when the DT-AD system is used for swine manure treatment from a model farm with 1000 pigs and the digested residue is used for forage rice production. A traditional swine manure treatment Oxidation Ditch system was used as the study control. The results suggest that methane yield using the proposed DT-AD system increased with a higher C/N ratio and shorter SRT. Correspondently, for the DT-AD system running with SRT of 80 days, the net energy yields for all treatments were negative, due to low biogas production and high heat loss of digestion tank. However, the biogas yield increased when the SRT was shortened to 40 days, and the generated energy was greater than consumed energy when C/N ratio was 20:1 and 30:1. The results suggest that with the correct optimization of C/N ratio and SRT, the proposed DT-AD system, followed by using digestate for forage rice production, can attain energy self-sufficiency.

  8. Mass and Energy Balances of Dry Thermophilic Anaerobic Digestion Treating Swine Manure Mixed with Rice Straw.

    Science.gov (United States)

    Zhou, Sheng; Zhang, Jining; Zou, Guoyan; Riya, Shohei; Hosomi, Masaaki

    2015-01-01

    To evaluate the feasibility of swine manure treatment by a proposed Dry Thermophilic Anaerobic Digestion (DT-AD) system, we evaluated the methane yield of swine manure treated using a DT-AD method with rice straw under different C/N ratios and solid retention time (SRT) and calculated the mass and energy balances when the DT-AD system is used for swine manure treatment from a model farm with 1000 pigs and the digested residue is used for forage rice production. A traditional swine manure treatment Oxidation Ditch system was used as the study control. The results suggest that methane yield using the proposed DT-AD system increased with a higher C/N ratio and shorter SRT. Correspondently, for the DT-AD system running with SRT of 80 days, the net energy yields for all treatments were negative, due to low biogas production and high heat loss of digestion tank. However, the biogas yield increased when the SRT was shortened to 40 days, and the generated energy was greater than consumed energy when C/N ratio was 20 : 1 and 30 : 1. The results suggest that with the correct optimization of C/N ratio and SRT, the proposed DT-AD system, followed by using digestate for forage rice production, can attain energy self-sufficiency.

  9. Heparanase affects food intake and regulates energy balance in mice.

    Directory of Open Access Journals (Sweden)

    Linda Karlsson-Lindahl

    Full Text Available Mutation of the melanocortin-receptor 4 (MC4R is the most frequent cause of severe obesity in humans. Binding of agouti-related peptide (AgRP to MC4R involves the co-receptor syndecan-3, a heparan sulfate proteoglycan. The proteoglycan can be structurally modified by the enzyme heparanase. Here we tested the hypothesis that heparanase plays a role in food intake behaviour and energy balance regulation by analysing body weight, body composition and food intake in genetically modified mice that either lack or overexpress heparanase. We also assessed food intake and body weight following acute central intracerebroventricular administration of heparanase; such treatment reduced food intake in wildtype mice, an effect that was abolished in mice lacking MC4R. By contrast, heparanase knockout mice on a high-fat diet showed increased food intake and maturity-onset obesity, with up to a 40% increase in body fat. Mice overexpressing heparanase displayed essentially the opposite phenotypes, with a reduced fat mass. These results implicate heparanase in energy balance control via the central melanocortin system. Our data indicate that heparanase acts as a negative modulator of AgRP signaling at MC4R, through cleavage of heparan sulfate chains presumably linked to syndecan-3.

  10. CHAMP gravity field recovery using the energy balance approach

    Directory of Open Access Journals (Sweden)

    Ch. Gerlach

    2003-01-01

    Full Text Available Since the early days of satellite geodesy energy balance based methods for gravity field determination have been considered. If non-conservative forces are known the Hamiltonian along the orbit is a constant of the motion. Thus the gravity field can be determined if position and velocity of the satellite are known and accelerometer measurements are available to model the non-conservative part. CHAMP is the first satellite that provides the user with those three kinds of data nearly continuously. Numerical investigations using real CHAMP data are presented to show the feasibility of the method. Using a semi-analytical approach the gravity field can be determined efficiently by a 2D-Fourier method. Those fast computations also give way to application of the method not only to a full gravity field recovery but also, e.g. for quick-look and validation of SST observations for satellite missions like CHAMP, GRACE or GOCE. The method can also be used for estimation of accelerometer calibration parameters.Key words. gravity field, energy balance, Jacobi-integral, non-conservative forces, accelerometer calibration, CHAMP

  11. Obesity and energy balance: is the tail wagging the dog?

    Science.gov (United States)

    Wells, J C K; Siervo, M

    2011-11-01

    The scientific study of obesity has been dominated throughout the twentieth century by the concept of energy balance. This conceptual approach, based on fundamental thermodynamic principles, states that energy cannot be destroyed, and can only be gained, lost or stored by an organism. Its application in obesity research has emphasised excessive appetite (gluttony), or insufficient physical activity (sloth), as the primary determinants of excess weight gain, reflected in current guidelines for obesity prevention and treatment. This model cannot explain why weight accumulates persistently rather than reaching a plateau, and underplays the effect of variability in dietary constituents on energy and intermediary metabolism. An alternative model emphasises the capacity of fructose and fructose-derived sweeteners (sucrose, high-fructose corn syrup) to perturb cellular metabolism via modification of the adenosine monophosphate (AMP)/adenosine triphosphate (ATP) ratio, activation of AMP kinase and compensatory mechanisms, which favour adipose tissue accretion and increased appetite while depressing physical activity. This conceptual model implicates chronic hyperinsulinaemia in the presence of a paradoxical state of 'cellular starvation' as a key driver of the metabolic modifications inducing chronic weight gain. We combine evidence from in vitro and in vivo experiments to formulate a perspective on obesity aetiology that emphasises metabolic flexibility and dietary composition rather than energy balance. Using this model, we question the direction of causation of reported associations between obesity and sleep duration or childhood growth. Our perspective generates new hypotheses, which can be tested to improve our understanding of the current obesity epidemic, and to identify novel strategies for prevention or treatment.

  12. Exercise, energy expenditure and energy balance, as measured with doubly labelled water.

    Science.gov (United States)

    Westerterp, Klaas R

    2018-02-01

    The doubly labelled water method for the measurement of total daily energy expenditure (TDEE) over 1-3 weeks under daily living conditions is the indicated method to study effects of exercise and extreme environments on energy balance. Subjects consume a measured amount of doubly labelled water (2H2 18O) to increase background enrichment of body water for 18O and 2H, and the subsequent difference in elimination rate between 18O and 2H, as measured in urine, saliva or blood samples, is a measure for carbon dioxide production and thus allows calculation of TDEE. The present review describes research showing that physical activity level (PAL), calculated as TDEE (assessed with doubly labelled water) divided by resting energy expenditure (REE, PAL = TDEE/REE), reaches a maximum value of 2·00-2·40 in subjects with a vigorously active lifestyle. Higher PAL values, while maintaining energy balance, are observed in professional athletes consuming additional energy dense foods to compete at top level. Exercise training can increase TDEE/REE in young adults to a value of 2·00-2·40, when energy intake is unrestricted. Furthermore, the review shows an exercise induced increase in activity energy expenditure can be compensated by a reduction in REE and by a reduction in non-exercise physical activity, especially at a negative energy balance. Additionally, in untrained subjects, an exercise-induced increase in activity energy expenditure is compensated by a training-induced increase in exercise efficiency.

  13. Nearly Net-Zero Exergy Districts as Models for Smart Energy Systems

    OpenAIRE

    Şiir Kilkiş

    2017-01-01

    The planning of urban settlements requires a targeted approach towards more sustainable energy, water, and environment systems. This research work analyses the city of Uppsala and a district that is an urban renewal project at the site of former high voltage power lines, namely Östra Sala backe, which will have a new energy concept. The latter is analysed based on proposals for two phases that aim to reach a net-zero district target based on the quality of energy (exergy). An indicator s...

  14. Energy balance, body composition, sedentariness and appetite regulation: pathways to obesity.

    OpenAIRE

    Hopkins, M; Blundell, JE

    2016-01-01

    Energy balance is not a simple algebraic sum of energy expenditure and energy intake as often depicted in communications. Energy balance is a dynamic process and there exist reciprocal effects between food intake and energy expenditure. An important distinction is that of metabolic and behavioural components of energy expenditure. These components not only contribute to the energy budget directly, but also by influencing the energy intake side of the equation. It has recently been demonstrate...

  15. Reciprocal Compensation to Changes in Dietary Intake and Energy Expenditure within the Concept of Energy Balance.

    Science.gov (United States)

    Drenowatz, Clemens

    2015-09-01

    An imbalance between energy intake and energy expenditure is the primary etiology for excess weight gain. Increased energy expenditure via exercise and energy restriction via diet are commonly used approaches to induce weight loss. Such behavioral interventions, however, have generally resulted in a smaller than expected weight loss, which in part has been attributed to compensatory adaptations in other components contributing to energy balance. Current research points to a loose coupling between energy intake and energy expenditure on a daily basis, and evidence for long-term adaptations has been inconsistent. The lack of conclusive evidence on compensatory adaptations in response to alterations in energy balance can be attributed to differences in intervention type and study population. Physical activity (PA) levels may be reduced in response to aerobic exercise but not in response to resistance exercise. Furthermore, athletic and lean adults have been shown to increase their energy intake in response to exercise, whereas no such response was observed in obese adults. There is also evidence that caloric restriction is associated with a decline in PA. Generally, humans seem to be better equipped to defend against weight loss than avoid weight gain, but results also show a large individual variability. Therefore, individual differences rather than group means should be explored to identify specific characteristics of "compensators" and "noncompensators." This review emphasizes the need for more research with simultaneous measurements of all major components contributing to energy balance to enhance the understanding of the regulation of energy balance, which is crucial to address the current obesity epidemic. © 2015 American Society for Nutrition.

  16. Skylab water balance analysis

    Science.gov (United States)

    Leonard, J. I.

    1977-01-01

    The water balance of the Skylab crew was analyzed. Evaporative water loss using a whole body input/output balance equation, water, body tissue, and energy balance was analyzed. The approach utilizes the results of several major Skylab medical experiments. Subsystems were designed for the use of the software necessary for the analysis. A partitional water balance that graphically depicts the changes due to water intake is presented. The energy balance analysis determines the net available energy to the individual crewman during any period. The balances produce a visual description of the total change of a particular body component during the course of the mission. The information is salvaged from metabolic balance data if certain techniques are used to reduce errors inherent in the balance method.

  17. [Hypothalamic inflammation and energy balance deregulations: focus on chemokines.

    Science.gov (United States)

    Le Thuc, Ophélia; Rovère, Carole

    2016-01-01

    The hypothalamus is a key brain region in the regulation of energy balance. It especially controls food intake and both energy storage and expenditure through integration of humoral, neural and nutrient-related signals and cues. Hypothalamic neurons and glial cells act jointly to orchestrate, both spatially and temporally, regulated metabolic functions of the hypothalamus. Thus, the existence of a causal link between hypothalamic inflammation and deregulations of feeding behavior, such as involuntary weight-loss or obesity, has been suggested. Among the inflammatory mediators that could induce deregulations of hypothalamic control of the energy balance, chemokines represent interesting candidates. Indeed, chemokines, primarily known for their chemoattractant role of immune cells to the inflamed site, have also been suggested capable of neuromodulation. Thus, chemokines could disrupt cellular activity together with synthesis and/or secretion of multiple neurotransmitters/mediators that are involved in the maintenance of energy balance. Here, we relate, on one hand, recent results showing the primary role of the central chemokinergic signaling CCL2/CCR2 for metabolic and behavioral adaptation to high-grade inflammation, especially loss of appetite and weight, through its activity on hypothalamic neurons producing the orexigenic peptide Melanin-Concentrating Hormone (MCH) and, on the other hand, results that suggest that chemokines could also deregulate hypothalamic neuropeptidergic circuits to induce an opposite phenotype and eventually participate in the onset/development of obesity. In more details, we will emphasize a study recently showing, in a model of high-grade acute inflammation of LPS injection in mice, that central CCL2/CCR2 signaling is of primary importance for several aspects explaining weight loss associated with inflammation: after LPS injection, animals lose weight, reduce their food intake, increase their fat oxidation (thus energy consumption from

  18. vNet Zero Energy for Radio Base Stations- Balearic Scenario

    DEFF Research Database (Denmark)

    Sabater, Pere; Mihovska, Albena Dimitrova; Pol, Andreu Moia

    2016-01-01

    The Balearic Islands have one of the best telecommunications infrastructures in Spain, with more than 1500 Radio Base Stations (RBS) covering a total surface of 4.991,66 km². This archipelago has high energy consumption, with high CO2 emissions, due to an electrical energy production system mainly...... based on coal and fossil fuels which is not an environmentally sustainable scenario. The aim of this study is to identify the processes that would reduce the energy consumption and greenhouse gas emissions, designing a target scenario featuring "zero CO2 emissions" and "100% renewable energies" in RBS....... The energy costs, CO2 emissions and data traffic data used for the study are generated by a sample of RBS from the Balearic Islands. The results are shown in terms of energy performance for a normal and net zero emissions scenarios....

  19. Reynolds number effects on scale energy balance in wall turbulence

    Science.gov (United States)

    Saikrishnan, Neelakantan; De Angelis, Elisabetta; Longmire, Ellen K.; Marusic, Ivan; Casciola, Carlo M.; Piva, Renzo

    2012-01-01

    The scale energy budget utilizes a modified version of the classical Kolmogorov equation of wall turbulence to develop an evolution equation for the second order structure function [R. J. Hill, "Exact second-order structure-function relationships," J. Fluid Mech. 468, 317 (2002)]. This methodology allows for the simultaneous characterization of the energy cascade and spatial fluxes in turbulent shear flows across the entire physical domain as well as the range of scales. The present study utilizes this methodology to characterize the effects of Reynolds number on the balance of energy fluxes in turbulent channel flows. Direct numerical simulation data in the range Reτ = 300-934 are compared to previously published results at Reτ = 180 [N. Marati, C. M. Casciola, and R. Piva, "Energy cascade and spatial fluxes in wall turbulence," J. Fluid Mech. 521, 191 (2004)]. The present results show no Reynolds number effects in the terms of the scale energy budget in either the viscous sublayer or buffer regions of the channel. In the logarithmic layer, the transfer of energy across scales clearly varies with Reynolds number, while the production of turbulent kinetic energy is not dependent on Reynolds number. An envelope of inverse energy cascade is quantified in the buffer region within which energy is transferred from small to larger scales. This envelope is observed in the range 6 < y+ < 37, where all scales except the smallest scales display characteristics of an inverse energy cascade. The cross-over scale lc+, which indicates the transition between production dominated and scale transfer dominated regimes, increases with Reynolds number, implying a larger range of transfer dominated scales, before the dominant mechanism switches to production. At higher Reynolds numbers, two distinct regimes of lc+ as a function of wall-normal location are observed, which was not captured at Reτ = 180. The variations of lc+ match the trends of the shear scale, which is a

  20. p75 neurotrophin receptor regulates energy balance in obesity

    Science.gov (United States)

    Baeza-Raja, Bernat; Sachs, Benjamin D.; Li, Pingping; Christian, Frank; Vagena, Eirini; Davalos, Dimitrios; Le Moan, Natacha; Ryu, Jae Kyu; Sikorski, Shoana L.; Chan, Justin P.; Scadeng, Miriam; Taylor, Susan S.; Houslay, Miles D.; Baillie, George S.; Saltiel, Alan R.; Olefsky, Jerrold M.; Akassoglou, Katerina

    2015-01-01

    Summary Obesity and metabolic syndrome reflect the dysregulation of molecular pathways that control energy homeostasis. Here we show that upon high-fat diet (HFD), the p75 neurotrophin receptor (p75NTR) controls energy expenditure in obese mice. Despite no changes in food intake, p75NTR-null mice were protected from HFD-induced obesity and remained lean due to increased energy expenditure, without developing insulin resistance or liver steatosis. p75NTR directly interacts with the catalytic subunit of protein kinase A (PKA) and regulates cAMP signaling in adipocytes, leading to decreased lipolysis and thermogenesis. Adipocyte-specific depletion of p75NTR or transplantation of p75NTR-null white adipose tissue (WAT) into wild-type mice fed a HFD protected against weight gain and insulin resistance. Our results reveal that signaling from p75NTR to cAMP/PKA regulates energy balance and suggest that non-neuronal functions of neurotrophin receptor signaling could be a new target for treating obesity and the metabolic syndrome. PMID:26748707

  1. [Strategies for successful weight reduction - focus on energy balance].

    Science.gov (United States)

    Weck, M; Bornstein, S R; Barthel, A; Blüher, M

    2012-10-01

    The prevalence of obesity and related health problems is increasing worldwide and also in Germany. It is well known that substantial and sustained weight loss is difficult to accomplish. Therefore, a variety of studies has been performed in order to specify causes for weight gain and create hypotheses for better treatment options. Key factors of this problem are an adaptation of energy metabolism, especially resting metabolic rate (RMR), non-exercise thermogenesis and diet induced thermogenesis. The extremely high failure rate (> 80%) to keep the reduced weight after successful weight loss is due to adaptation processes of the body to maintain body energy stores. This so called "adaptive thermogenesis" is defined as a smaller than predicted change of energy expenditure in response to changes in energy balance. Adaptive thermogenesis appears to be a major reason for weight regain. The foremost objective of weight-loss programs is the reduction in body fat. However, a concomitant decline in lean tissue can frequently be observed. Since lean body mass (LBM) represents a key determinant of RMR it follows that a decrease in lean tissue could counteract the progress of weight loss. Therefore, with respect to long-term effectiveness of weight reduction programs, the loss of fat mass while maintaining LBM and RMR seems desirable. In this paper we will discuss the mechanisms of adaptive thermogenesis and develop therapeutic strategies with respect to avoiding weight regain successful weight reduction. © Georg Thieme Verlag KG Stuttgart · New York.

  2. Hypothalamic Wnt Signalling and its Role in Energy Balance Regulation.

    Science.gov (United States)

    Helfer, G; Tups, A

    2016-03-01

    Wnt signalling and its downstream effectors are well known for their roles in embryogenesis and tumourigenesis, including the regulation of cell proliferation, survival and differentiation. In the nervous system, Wnt signalling has been described mainly during embryonic development, although accumulating evidence suggests that it also plays a major role in adult brain morphogenesis and function. Studies have predominantly concentrated on memory formation in the hippocampus, although recent data indicate that Wnt signalling is also critical for neuroendocrine control of the developed hypothalamus, a brain centre that is key in energy balance regulation and whose dysfunction is implicated in metabolic disorders such as type 2 diabetes and obesity. Based on scattered findings that report the presence of Wnt molecules in the tanycytes and ependymal cells lining the third ventricle and arcuate nucleus neurones of the hypothalamus, their potential importance in key regions of food intake and body weight regulation has been investigated in recent studies. The present review brings together current knowledge on Wnt signalling in the hypothalamus of adult animals and discusses the evidence suggesting a key role for members of the Wnt signalling family in glucose and energy balance regulation in the hypothalamus in diet-induced and genetically obese (leptin deficient) mice. Aspects of Wnt signalling in seasonal (photoperiod sensitive) rodents are also highlighted, given the recent evidence indicating that the Wnt pathway in the hypothalamus is not only regulated by diet and leptin, but also by photoperiod in seasonal animals, which is connected to natural adaptive changes in food intake and body weight. Thus, Wnt signalling appears to be critical as a modulator for normal functioning of the physiological state in the healthy adult brain, and is also crucial for normal glucose and energy homeostasis where its dysregulation can lead to a range of metabolic disorders. © 2016

  3. Transformations, Inc.. Partnering To Build Net-Zero Energy Houses in Massachusetts

    Energy Technology Data Exchange (ETDEWEB)

    Ueno, K. [Building Science Corporation, Somerville, MA (United States); Bergey, D. [Building Science Corporation, Somerville, MA (United States); Wytrykowska, H. [Building Science Corporation, Somerville, MA (United States)

    2013-09-01

    Transformations, Inc. is a residential development and building company that has partnered with Building Science Corporation to build new construction net-zero energy houses in Massachusetts under the Building America program. There are three communities that will be constructed through this partnership: Devens Sustainable Housing ("Devens"), The Homes at Easthampton Meadow ("Easthampton") and Phase II of the Coppersmith Way Development ("Townsend"). This report intends to cover all of the single-family new construction homes that have been completed to date. The houses built in these developments are net zero energy homes built in a cold climate. They will contribute to finding answers to specific research questions for homes with high R double stud walls and high efficiency ductless air source heat pump systems ("mini-splits"); allow to explore topics related to the financing of photovoltaic systems and basements vs. slab-on-grade construction; and provide feedback related to the performance of ductless mini-split air source heat pumps.

  4. Humus and energy balances and greenhouse gas emissions with compost fertilization in organic farming compared with mineral fertilization

    Science.gov (United States)

    Erhart, Eva; Schmid, Harald; Hülsbergen, Kurt-Jürgen; Hartl, Wilfried

    2015-04-01

    Humus and energy balances and greenhouse gas emissions with compost fertilization in organic farming compared with mineral fertilization E. Erhart, H. Schmid, K.-J. Hülsbergen, W. Hartl The positive effects of compost fertilization on soil humus with their associated benefits for soil quality are well-established. The aim of the present study was to assess the effect of compost fertilization on humus and energy balances and greenhouse gas emissions and to compare the results of the humus balances with the changes in soil organic carbon contents measured in the soil of the experimental field. In order to assess the effects of compost use in organic farming as compared to conventional farming practice using mineral fertilizers, the field experiment with compost fertilization 'STIKO' was set up in 1992 near Vienna, Austria, on a Molli-gleyic Fluvisol. It included three treatments with compost fertilization (C1, C2 and C3 with 8, 14 and 20 t ha-1 y-1 f. m. on average of 14 years), three treatments with mineral nitrogen fertilization (N1, N2 and N3 with 29, 46 and 63 kg N ha-1 y 1 on average) and an unfertilized control (0) in six replications in a latin rectangle design. In the field trial, biowaste compost from the composting plant of the City of Vienna was used. Data from the field experiment (from 14 experimental years) were fed into the model software REPRO to calculate humus and energy balances and greenhouse gas emissions. The model software REPRO (REPROduction of soil fertility) couples the balancing of C, N and energy fluxes. For the determination of the net greenhouse effect, REPRO performs calculations of C sequestration in the soil, CO2 emissions from the use of fossil energy and N2O emissions from the soil. Humus balances showed that compost fertilization at a rate of 8 t ha-1 y-1 (C1) resulted in a positive humus balance of +115 kg C ha-1 y-1. With 14 and 20 t ha-1 y-1 compost (C2 and C3), respectively, humus accumulated at rates of 558 and 1021 kg C ha-1

  5. Energy Balance of Triathletes during an Ultra-Endurance Event

    Directory of Open Access Journals (Sweden)

    Anna Barrero

    2014-12-01

    Full Text Available The nutritional strategy during an ultra-endurance triathlon (UET is one of the main concerns of athletes competing in such events. The purpose of this study is to provide a proper characterization of the energy and fluid intake during real competition in male triathletes during a complete UET and to estimate the energy expenditure (EE and the fluid balance through the race. Methods: Eleven triathletes performed a UET. All food and drinks ingested during the race were weighed and recorded in order to assess the energy intake (EI during the race. The EE was estimated from heart rate (HR recordings during the race, using the individual HR-oxygen uptake (Vo2 regressions developed from three incremental tests on the 50-m swimming pool, cycle ergometer, and running treadmill. Additionally, body mass (BM, total body water (TBW and intracellular (ICW and extracellular water (ECW were assessed before and after the race using a multifrequency bioimpedance device (BIA. Results: Mean competition time and HR was 755 ± 69 min and 137 ± 6 beats/min, respectively. Mean EI was 3643 ± 1219 kcal and the estimated EE was 11,009 ± 664 kcal. Consequently, athletes showed an energy deficit of 7365 ± 1286 kcal (66.9% ± 11.7%. BM decreased significantly after the race and significant losses of TBW were found. Such losses were more related to a reduction of extracellular fluids than intracellular fluids. Conclusions: Our results confirm the high energy demands of UET races, which are not compensated by nutrient and fluid intake, resulting in a large energy deficit.

  6. Compensatory Changes in Energy Balance Regulation over One Athletic Season.

    Science.gov (United States)

    Silva, Analiza M; Matias, Catarina N; Santos, Diana A; Thomas, Diana; Bosy-Westphal, Anja; MüLLER, Manfred J; Heymsfield, Steven B; Sardinha, LUíS B

    2017-06-01

    Mechanisms in energy balance (EB) regulation may include compensatory changes in energy intake (EI) and metabolic adaption (MA), but information is unavailable in athletes who often change EB components. We aim to investigate EB regulation compensatory mechanisms over one athletic season. Fifty-seven athletes (39 males/18 females; handball, volleyball, basketball, triathlon, and swimming) were evaluated from the beginning to the competitive phase of the season. Resting and total energy expenditure (REE and TEE, respectively) were assessed by indirect calorimetry and doubly labeled water, respectively, and physical activity energy expenditure was determined as TEE - 0.1(TEE) - REE. Fat mass (FM) and fat-free mass (FFM) were evaluated by dual-energy x-ray absorptiometry and changed body energy stores was determined by 1.0(ΔFFM/Δtime) + 9.5(ΔFM/Δtime). EI was derived as TEE + EB. REE was predicted from baseline FFM, FM, sex, and sports. %MA was calculated as 100(measured REE/predicted REE-1) and MA (kcal) as %MA/100 multiplied by baseline measured REE. Average EI minus average physical activity energy expenditure was computed as a proxy of average energy availability, assuming that a constant nonexercise EE occurred over the season. Body mass increased by 0.8 ± 2.5 kg (P < 0.05), but a large individual variability was found ranging from -6.1 to 5.2 kg. The TEE raise (16.8% ± 11.7%) was compensated by an increase EI change (16.3% ± 12.0%) for the whole group (P < 0.05). MA was found in triathletes, sparing 128 ± 168 kcal·d, and basketball players, dissipating 168 ± 205 kcal·d (P < 0.05). MA was associated (P < 0.05) with EB and energy availability (r = 0.356 and r = 0.0644, respectively). TEE increased over the season without relevant mean changes in weight, suggesting that EI compensation likely occurred. The thrifty or spendthrift phenotypes observed among sports and the demanding workloads these athletes are exposed to highlight the need for sport

  7. Biological disintegration of microalgae for biomethane recovery-prediction of biodegradability and computation of energy balance.

    Science.gov (United States)

    Kavitha, S; Yukesh Kannah, R; Rajesh Banu, J; Kaliappan, S; Johnson, M

    2017-11-01

    The present study investigates the synergistic effect of combined bacterial disintegration on mixed microalgal biomass for energy efficient biomethane generation. The rate of microalgal biomass lysis, enhanced biodegradability, and methane generation were used as indices to assess efficiency of the disintegration. A maximal dissolvable organics release and algal biomass lysis rate of about 1100, 950 and 800mg/L and 26, 23 and 18% was achieved in PA+C (protease, amylase+cellulase secreting bacteria), C (cellulase alone) and PA (protease, amylase) microalgal disintegration. During anaerobic fermentation, a greater production of volatile fatty acids (1000mg/L) was noted in PA+C bacterial disintegration of microalgal biomass. PA+C bacterial disintegration improve the amenability of microalgal biomass to biomethanation process with higher biodegradability of about 0.27gCOD/gCOD, respectively. The energy balance analysis of this combined bacterial disintegration of microalgal biomass provides surplus positive net energy (1.14GJ/d) by compensating the input energy requirements. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. The energy balance of a self-sufficient building; De energiebalans van een autarkisch gebouw

    Energy Technology Data Exchange (ETDEWEB)

    Doedens, B. [Technische Universieit Eindhoven, Eindhoven (Netherlands); Weisscher, B.; De Wildt, M. [Grontmij, Technical Management, Amersfoort (Netherlands)

    2006-05-15

    A self-sufficient (autarkic) building is one in which all the required energy is generated in a sustainable way by the building. The goal of the study described in this article is to determine the optimum relation between the capacities of a wind turbine and solar panels in an office building using a combination of these technologies to obtain a 100% sustainable electricity supply. A method was also developed to establish the size of the energy buffer required to keep the energy demand and supply in balance. The results are applied to an autarkic building, i.e. one without a connection to the public network. [Dutch] In een zelfvoorzienend (autarkisch) gebouw wordt alle benodigde energie op duurzame wijze door het gebouw zelf opgewekt. Het doel van het in dit artikel beschreven onderzoek is om voor een kantoorgebouw, waarbij de elektriciteit 100% duurzaam wordt opgewekt met zonnepanelen en windmolens, de optimale verhouding tussen het vermogen van de windmolen en de PV-panelen te bepalen. Ook is een methode ontwikkeld om de grootte van de energiebuffer te bepalen, die nodig is om energievraag en energieaanbod in balans te brengen. De resultaten zijn toegepast op een principieel autarkisch gebouw, dus zonder koppeling met her openbare net.

  9. Obesity as malnutrition: the dimensions beyond energy balance.

    Science.gov (United States)

    Wells, J C K

    2013-05-01

    The aetiology of obesity is seemingly simple to understand: individuals consume more energy than they expend, with the excess energy being stored in adipose tissue. Public health campaigns therefore promote dietary restraint and physical exercise, and emphasize individual responsibility for these behaviours. Increasingly, however, researchers are switching from thermodynamic to metabolic models of obesity, thereby clarifying how specific environmental factors promote lipogenesis. Obesity can best be explained not by counting 'calories in and out', but by understanding how specific dietary products and activity behaviours perturb cellular metabolism and promote net lipogenesis. This metabolic approach can furthermore be integrated with more sophisticated models of how commercial practices drive the consumer trends that promote obesogenic behaviours. Notably, obesity treatment has proven more effective if it bypasses individual responsibility, suggesting that a similar approach placing less emphasis on individual responsibility would improve the efficacy of obesity prevention. Successful obesity prevention campaigns are likely to emerge only when the public receive better 'protection' from the commercial practices that are driving the global obesity epidemic. Rather than populations failing to heed governments' public health advice, governments are currently failing the public by abandoning their responsibility for regulating commercial activities.

  10. Global energy balance of COSIPA in 1990; Balanco energetico global da COSIPA em 1990

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Nicola Roberto de; Silva, Clovis Aprigio da; Veiga, Wagner [Companhia Siderurgica Paulista (Brazil)

    1991-12-31

    This report shows relevant aspects about energy account in a Brazilian metal industry, COSIPA - Companhia Siderurgica Paulista. The energy balances from each unit of this steel making are carried out, and data on energy consumption in blast furnaces, fuel balances and its supply of energy are presented. 24 figs., 31 tabs

  11. Quantifying the impacts of snow on surface energy balance through assimilating snow cover fraction and snow depth

    Science.gov (United States)

    Meng, Chunlei

    2017-10-01

    Seasonal snow plays an important part in Earth's climate system. Snow cover regulates the land surface energy balance through altering the albedo of the land surface. To utilize the satellite-retrieved snow cover fraction (SCF) and snow depth (SD) data sufficiently and avoid inconsistency, this paper developed a very simple but robust quality control method to assimilate Fengyun satellite-retrieved SCF and SD simultaneously. The results show that the assimilation method which this paper implemented can not only utilize the satellite-retrieved SCF and SD data sufficiently but also avoid the inconsistency of them. Two experiments were designed and performed to quantify the impacts of snow on land surface energy balance using the integrated urban land model. With the increase of the SCF and SD, the net radiation decreased significantly during the day and increased a little at night; the sensible heat flux decreased significantly during the day; the evapotranspiration and ground heat flux decreased during the day too.

  12. Energy and Greenhouse gas balances of the utilisation of biogas for energy

    DEFF Research Database (Denmark)

    Nielsen, Per Sieverts; Karlsson, Kenneth Bernard; Holm-Nielsen, Jens Bo

    1998-01-01

    The utilisation of biogas for energy is an important part of the Danish energy plan for reducing Danish emissions of greenhouse gases. Implementation programmes for new biogas plants have been in operation since 1990, promoted by the Ministry of Environment and Energy. The focus of the implementa......The utilisation of biogas for energy is an important part of the Danish energy plan for reducing Danish emissions of greenhouse gases. Implementation programmes for new biogas plants have been in operation since 1990, promoted by the Ministry of Environment and Energy. The focus...... biogas for energy. Two different Danish joint biogas plants are evaluated with the aim of determining the role of transportation and co-fermentation on the energy and the balance of greenhouse gases from the biogas fuel cycle....

  13. Comparing World Economic and Net Energy Metrics, Part 2: Total Economy Expenditure Perspective

    Directory of Open Access Journals (Sweden)

    Carey W. King

    2015-11-01

    Full Text Available We translate between energetic and economic metrics that characterize the role of energy in the economy. Specifically, we estimate monetary expenditures for the primary energy and net external power ratio (NEPR direct ; NEPR, net external power ratio, a power return ratio of annual energy production divided by annual direct energy inputs within the energy industry. We estimate these on an annualized basis for forty-four countries from 1978 to 2010. Expressed as a fraction of gross domestic product (GDP, f e , GDP , the forty-four country aggregate (composing >90% world GDP worldwide expenditures on energy decreased from a maximum of 10.3% in 1979 to a minimum of 3.0% in 1998 before increasing to a second peak of 8.1% in 2008. While the global f e , GDP fluctuates significantly, global NEPR direct declined from a value of 34 in 1980 to 17 in 1986 before staying in a range between 14 and 16 from 1991 to 2010. In comparing both of these metrics as ratios of power output over power input, one economic ( f e , GDP - 1 and one biophysical (NEPR direct , we see that when the former divided by the latter is below unity, the world was in a low-growth or recessionary state.

  14. Modeling and Optimizing Energy Utilization of Steel Production Process: A Hybrid Petri Net Approach

    Directory of Open Access Journals (Sweden)

    Peng Wang

    2013-01-01

    Full Text Available The steel industry is responsible for nearly 9% of anthropogenic energy utilization in the world. It is urgent to reduce the total energy utilization of steel industry under the huge pressures on reducing energy consumption and CO2 emission. Meanwhile, the steel manufacturing is a typical continuous-discrete process with multiprocedures, multiobjects, multiconstraints, and multimachines coupled, which makes energy management rather difficult. In order to study the energy flow within the real steel production process, this paper presents a new modeling and optimization method for the process based on Hybrid Petri Nets (HPN in consideration of the situation above. Firstly, we introduce the detailed description of HPN. Then the real steel production process from one typical integrated steel plant is transformed into Hybrid Petri Net model as a case. Furthermore, we obtain a series of constraints of our optimization model from this model. In consideration of the real process situation, we pick the steel production, energy efficiency and self-made gas surplus as the main optimized goals in this paper. Afterwards, a fuzzy linear programming method is conducted to obtain the multiobjective optimization results. Finally, some measures are suggested to improve this low efficiency and high whole cost process structure.

  15. Final Technical Report for the Net-Zero Energy Commercial Buildings Consortium

    Energy Technology Data Exchange (ETDEWEB)

    Fazeli, Sandy [National Association of State Energy Officials, Arlington, VA (United States)

    2014-09-30

    The Commercial Buildings Consortium (CBC) was established in 2009, under the chairmanship of the National Association of State Energy Officials (NASEO), as a supporting organization to the Commercial Buildings Initiative (CBI). The CBI was created by Congress through the Energy Independence and Security Act of 2007 (EISA) and launched by the Department of Energy (DOE) in 2008 with the goal to “develop and disseminate technologies, practices, and policies for establishment of zero net energy commercial buildings.”. The impact of the CBC since 2009 has been multifold, resulting in increased collaboration, increased innovation, and increased demonstration and deployment. During the project performance period of 2009-2014, the CBC provided an organizational framework for sustained public-private collaboration among more than 600 commercial building professionals, researchers and educators, utilities, and government agencies at federal, state, and local level. The CBC’s research has identified emerging technologies, market strategies, and innovative public and corporate policies to help advance CBI’s zero-net-energy. Finally, the CBC worked in close partnership with DOE’s commercial building teams and the Better Buildings Alliances to identify opportunities for proving out and deploying energy-saving technologies and practices.

  16. The Sleep/Wake Cycle is Directly Modulated by Changes in Energy Balance

    OpenAIRE

    Collet Tinh-Hai; van, der Klaauw Agatha A; Henning Elana; Keogh Julia M.; Suddaby Diane; Dachi Sekesai V; Dunbar Síle; Kelway Sarah; Dickson Suzanne L; Farooqi I. Sadaf; Schmid Sebastian M

    2016-01-01

    The rise in obesity has been paralleled by a decline in sleep duration in epidemiological studies. However the potential mechanisms linking energy balance and the sleep/wake cycle are not well understood. We aimed to examine the effects of manipulating energy balance on the sleep/wake cycle. Twelve healthy normal weight men were housed in a clinical research facility and studied at three time points: baseline after energy balance was disrupted by 2 days of caloric restriction to 10 of energy ...

  17. The role of sleep duration in the regulation of energy balance: effects on energy intakes and expenditure

    National Research Council Canada - National Science Library

    St-Onge, Marie-Pierre

    2013-01-01

    .... Clinical intervention studies have examined whether reducing sleep in normal sleepers, typically sleeping 7-9 h/night, can affect energy intake, energy expenditure, and endocrine regulators of energy balance...

  18. [Obesity based on mutation of genes involved in energy balance].

    Science.gov (United States)

    Hainerová, I

    2007-01-01

    Within the last decade an intensive research led to an identification of several genes which are involved in a regulation of energy balance. In most cases, carriers of these gene mutations do not exhibit further characteristic phenotypic features except for a severe obesity. Obesity based on mutation of one gene product is called monogenic obesity. Mutations in genes for leptin, leptin receptor, proopiomelanocortin, prohormone convertase 1, melanocortin 4 and 3 receptor disrupt the physiological humoral signalization between peripheral signals and the hypothalamic centres of satiety and hunger. Defects of all above mentioned genes lead to phenotype of abnormal eating behaviour followed by a development of severe early-onset obesity. Mutations of melanocortin 4 receptor gene represent the most common cause of monogenic obesity because they are detected in almost 6 % children with early-onset severe obesity. Mutations of the other genes involved in energy homeostasis are very rare. Although these mutations are sporadic we assume that further research of monogenic forms of obesity might lead to our understanding of physiology and pathophysiology of regulation of the energy homeostasis and eating behaviour. Additionally, they may open new approach to the management of eating behaviour and to the treatment of obesity.

  19. Effects of neonatal programming on hypothalamic mechanisms controlling energy balance.

    Science.gov (United States)

    Contreras, C; Novelle, M G; Leis, R; Diéguez, C; Skrede, S; López, M

    2013-12-01

    The prevalence of overweight and obesity in most developed countries has markedly increased during the last decades. In addition to genetic, hormonal, and metabolic influences, environmental factors like fetal and neonatal nutrition play key roles in the development of obesity. Interestingly, overweight during critical developmental periods of fetal and/or neonatal life has been demonstrated to increase the risk of obesity throughout juvenile life into adulthood. In spite of this evidence, the specific mechanisms underlying this fetal/neonatal programming are not perfectly understood. However, it is clear that circulating hormones such as insulin and leptin play a critical role in the development and programming of hypothalamic circuits regulating energy balance. Here, we review what is currently known about the impact of perinatal malnutrition on the mechanisms regulating body weight homeostasis. Understanding these molecular mechanisms may provide new targets for the treatment of obesity. © Georg Thieme Verlag KG Stuttgart · New York.

  20. Geospatial and Contextual Approaches to Energy Balance and Health.

    Science.gov (United States)

    Berrigan, David; Hipp, J Aaron; Hurvitz, Philip M; James, Peter; Jankowska, Marta M; Kerr, Jacqueline; Laden, Francine; Leonard, Tammy; McKinnon, Robin A; Powell-Wiley, Tiffany M; Tarlov, Elizabeth; Zenk, Shannon N

    In the past 15 years, a major research enterprise has emerged that is aimed at understanding associations between geographic and contextual features of the environment (especially the built environment) and elements of human energy balance, including diet, weight, and physical activity. Here we highlight aspects of this research area with a particular focus on research and opportunities in the United States as an example. We address four main areas: 1) The importance of valid and comparable data concerning behavior across geographies, 2) The ongoing need to identify and explore new environmental variables, 3) The challenge of identifying the causally relevant context, and 4) The pressing need for stronger study designs and analytical methods. Additionally, we discuss existing sources of geo-referenced health data which might be exploited by interdisciplinary research teams, personnel challenges and some aspects of funding for geospatial research by the US National Institutes of Health in the past decade, including funding for international collaboration and training opportunities.

  1. Geospatial and Contextual Approaches to Energy Balance and Health

    Science.gov (United States)

    Berrigan, David; Hipp, J. Aaron; Hurvitz, Philip M.; James, Peter; Jankowska, Marta M.; Kerr, Jacqueline; Laden, Francine; Leonard, Tammy; McKinnon, Robin A.; Powell-Wiley, Tiffany M.; Tarlov, Elizabeth; Zenk, Shannon N.

    2016-01-01

    In the past 15 years, a major research enterprise has emerged that is aimed at understanding associations between geographic and contextual features of the environment (especially the built environment) and elements of human energy balance, including diet, weight, and physical activity. Here we highlight aspects of this research area with a particular focus on research and opportunities in the United States as an example. We address four main areas: 1) The importance of valid and comparable data concerning behavior across geographies, 2) The ongoing need to identify and explore new environmental variables, 3) The challenge of identifying the causally relevant context, and 4) The pressing need for stronger study designs and analytical methods. Additionally, we discuss existing sources of geo-referenced health data which might be exploited by interdisciplinary research teams, personnel challenges and some aspects of funding for geospatial research by the US National Institutes of Health in the past decade, including funding for international collaboration and training opportunities. PMID:27076868

  2. Effects of ghrelin in energy balance and body weight homeostasis.

    Science.gov (United States)

    Mihalache, Laura; Gherasim, Andreea; Niță, Otilia; Ungureanu, Maria Christina; Pădureanu, Sergiu Serghei; Gavril, Radu Sebastian; Arhire, Lidia Iuliana

    2016-02-01

    Ghrelin is a gut peptide composed of 28 amino acids mostly secreted in the gastric fundus mucosa. It was isolated and described in 1999 by Kojima et al. and only three years later its specific receptor, GHSR1a, was also identified. Ghrelin, the endogenous ligand for the GH secretagogue receptor, is the only peripheral orexigenic hormone that activates the receptors to be found especially in the appetite center (hypothalamus and pituitary gland). Ghrelin is present in human plasma in two forms: an inactive form known as deacylated ghrelin, and an active form called acylated ghrelin synthesized under the action of ghrelin O-acyltransferase enzyme (GOAT). The literature even mentions an extremely complex ghrelin/GOAT/GHSR system involved in the regulation of human energy, metabolism and adaptation of energy homeostasis to environmental changes. In humans, there is a preprandial rise and a postprandial fall in plasma ghrelin levels, which strongly suggest that the peptide plays a physiological role in meal initiation and may be employed in determining the amount and quality of ingested food. Besides the stimulation of food intake, ghrelin determines a decrease in energy expenditure and promotes the storage of fatty acids in adipocytes. Thus, in the human body ghrelin induces a positive energy balance, an increased adiposity gain, as well as an increase in caloric storage, seen as an adaptive mechanism to caloric restriction conditions. In the current world context, when we are witnessing an increasing availability of food and a reduction of energy expenditure to a minimum level, these mechanisms have become pathogenic. As a consequence, the hypothesis that ghrelin is involved in the current obesity epidemic has been embraced by many scholars and researchers.

  3. Energy balances in the production and end use of alcohols derived from biomass. A fuels-specific comparative analysis of alternate ethanol production cycles

    Energy Technology Data Exchange (ETDEWEB)

    1980-10-01

    Considerable public interest and debate have been focused on the so-called energy balance issue involved in the conversion of biomass materials into ethanol for fuel use. This report addresses questions of net gains in premium fuels that can be derived from the production and use of ethanol from biomass, and shows that for the US alcohol fuel program, energy balance need not be a concern. Three categories of fuel gain are discussed in the report: (1) Net petroleum gain; (2) Net premium fuel gain (petroleum and natural gas); and (3) Net energy gain (for all fuels). In this study the investment of energy (in the form of premium fuels) in alcohol production includes all investment from cultivating, harvesting, or gathering the feedstock and raw materials, through conversion of the feedstock to alcohol, to the delivery to the end-user. To determine the fuel gains in ethanol production, six cases, encompassing three feedstocks, five process fuels, and three process variations, have been examined. For each case, two end-uses (automotive fuel use and replacement of petrochemical feedstocks) were scrutinized. The end-uses were further divided into three variations in fuel economy and two different routes for production of ethanol from petrochemicals. Energy requirements calculated for the six process cycles accounted for fuels used directly and indirectly in all stages of alcohol production, from agriculture through distribution of product to the end-user. Energy credits were computed for byproducts according to the most appropriate current use.

  4. Daily physical activity as determined by age, body mass and energy balance.

    Science.gov (United States)

    Westerterp, Klaas R

    2015-06-01

    Insight into the determinants of physical activity, including age, body mass and energy balance, facilitates the design of intervention studies with body mass and energy balance as determinants of health and optimal performance. An analysis of physical activity energy expenditure in relation to age and body mass and in relation to energy balance, where activity energy expenditure is derived from daily energy expenditure as measured with doubly labelled water and body movement is measured with accelerometers, was conducted in healthy subjects under daily living conditions over intervals of one or more weeks. Activity energy expenditure as a fraction of daily energy expenditure is highest in adults at the reproductive age. Then, activity energy expenditure is a function of fat-free mass. Excess body mass as fat does not affect daily activity energy expenditure, but body movement decreases with increasing fatness. Overweight and obesity possibly affect daily physical activity energy expenditure through endurance. Physical activity is affected by energy availability; a negative energy balance induces a reduction of activity expenditure. Optimal performance and health require prevention of excess body fat and maintenance of energy balance, where energy balance determines physical activity rather than physical activity affecting energy balance.

  5. Effect of pre-partum prilled fat supplementation on feed intake, energy balance and milk production in Murrah buffaloes

    Directory of Open Access Journals (Sweden)

    Shikha Sharma

    2016-03-01

    Full Text Available Aim: To investigate the effect of pre-partum prilled fat feeding on dry matter intake (DMI, energy balance and milk production in Murrah buffaloes. Materials and Methods: Advance pregnant Murrah buffaloes were either received a dietary supplement of prilled fat at 100 g/day for 35 days pre-partum and at 150 g/day for 95 days post-partum (supplemented group [SG] or did not receive fat supplement (control group [CG]. DMI and the yields of milk and milk component were measured. A body condition score (BCS was recorded. Energy balance and gross feed efficiency (GFE were calculated. DMI and BCS were recorded and milk yield (MY, fat, protein, lactose, solid not fat, energy balance were measured. The fat corrected milk yield was calculated. Results: The DMI was non-significant between groups and periods of study. BCS of buffaloes improved in the SG than CG (p<0.01. The energy intake in terms of total digestible nutrients (TDN%, TDN intake, digestible energy (DE, metabolizable energy/kg of milk, DE of milk, net energy, and GFE were higher (p<0.01 in SG during post-partum period. Crude protein intake was statistically similar in both the groups. MY was higher (p<0.01 in SG than in CG during 95 days of early lactation. Milk fat, fat corrected MY was higher (p<0.01 in SG however protein, lactose and solid not fat content did not varied between the groups. The feed efficiency of the SG was higher (p<0.01 than the CG during the post-partum period. Conclusion: It was inferred that prilled fat supplementation augments energy balance and milk production in transition Murrah buffaloes.

  6. Responses in live weight change to net energy intake in dairy cows

    DEFF Research Database (Denmark)

    Jensen, Charlotte; Østergaard, Søren; Bertilsson, Jan

    2015-01-01

    or multiparous. Feed ration energy values were recalculated by use of NorFor to obtain consistent energy expression in all trials as opposed to the varying feed evaluation systems used in original analysis of trials. Regression analysis with linear and quadratic effects were performed on live weight......The objective of this analysis was to estimate the effect of increased energy intake on daily live weight changes during the first 100 days of lactation of primiparous and multiparous cows. A data set with 78 observations (treatment means) was compiled from 6 production trials from Denmark, Norway...... change were made by linear mixed effects model with trial as random factor. For both primiparous and multiparous cows there was an increasing curvilinear response at a decreasing rate to increased net energy intake and the daily live weight change at day 30 was negative and at day 90 it was positive...

  7. Net Zero Fort Carson: Integrating Energy, Water, and Waste Strategies to Lower the Environmental Impact of a Military Base

    Science.gov (United States)

    Military bases resemble small cities and face similar sustainability challenges. As pilot studies in the U.S. Army Net Zero program, 17 locations are moving to 100% renewable energy, zero depletion of water resources, and/or zero waste to landfill by 2020. Some bases target net z...

  8. Energy balance in high-power CO2 laser welding

    Science.gov (United States)

    Del Bello, Umberto; Rivela, Cristina; Cantello, Maichi; Penasa, Mauro

    1991-10-01

    The laser energy impinging on a metal workpiece is partially absorbed and partially reflected by the material surface. This work is aimed at gaining a better insight into the energy balance of the process, and it can also provide the correct input for process modeling and the optimum choice of parameters for increasing welding efficiency. Measurements of the absorption coefficient were made using platinum-platinum rhodium thermocouples which monitored the temperature rise. The radiation backscattered by the workpiece or plasma plume was also recorded, and tests were performed to measure the total amount of material lost by evaporation during laser welding. All the tests were performed on austenitic stainless steel. The resulting absorption curves show different behavior at low or high speed and this can be explained only by taking into account the influence on the process of both the size and inclination of the keyhole. To conserve the keyhole, the interaction process must be rapidly interrupted so as to freeze the molten material and preserve the cavity in the form assumed during the process. A fast mechanical switch has been devised and tests seem to confirm the assumption made.

  9. Natriuretic peptide control of energy balance and glucose homeostasis.

    Science.gov (United States)

    Coué, Marine; Moro, Cedric

    2016-05-01

    Cardiac natriuretic peptides (NP) have recently emerged as metabolic hormones. Physiological stimulation of cardiac NP release as during exercise may contribute to increase fatty acid mobilization from adipose tissue and their oxidation by skeletal muscles. Clinical studies have shown that although very high plasma NP level characterizes cardiac dysfunction and heart failure, a consistently reduced plasma NP level is observed in metabolic diseases such as obesity and type 2 diabetes. A low circulating NP level also predicts the risk of new onset type 2 diabetes. It is unclear at this stage if the "natriuretic handicap" observed in obesity is causally associated with the incidence of type 2 diabetes. Recent work indicates that NP can activate a thermogenic program in brown and white fat, increase energy expenditure and inhibit food intake. Mouse studies also argue for a key role of NP in the regulation of energy balance and glucose homeostasis. This review will focus on recent human and mouse studies to highlight the metabolic roles of NP and their potential relevance in the context of obesity and type 2 diabetes. Copyright © 2015 Elsevier B.V. and Société Française de Biochimie et Biologie Moléculaire (SFBBM). All rights reserved.

  10. Brazilian energy balance 1998: calendar year 1997; Balanco energetico nacional 1998: ano base 1997

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-07-01

    This report shows the energy flows of different primary and secondary sources, from the production to the final consumption in every sector of the Brazilian economy, for the calendar year 1995. It's divided into nine sections, as follows: summary; energy supply and consumption by source; energy consumption by sector; energy foreign trading; transformation center balances ;energy resources and reserves; energy and socio economy; regional parameters; and appendices - installed capacity, international data, general structure of the balance, information processing, conversion units and consolidated energy balances.

  11. Brazilian energy balance 1996: calendar year 1995; Balanco energetico nacional 1996: ano base 1995

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-07-01

    This report shows the energy flows of different primary and secondary sources, from the production to the final consumption in every sector of the Brazilian economy, for the calendar year 1995. It's divided into nine sections, as follows: summary; energy supply and consumption by source; energy consumption by sector; energy foreign trading; transformation center balances ;energy resources and reserves; energy and socio economy; regional parameters; and appendices - installed capacity, international data, general structure of the balance, information processing, conversion units and consolidated energy balances.

  12. Turbulent flux variability and energy balance closure in the TERENO prealpine observatory: a hydrometeorological data analysis

    Science.gov (United States)

    Soltani, Mohsen; Mauder, Matthias; Laux, Patrick; Kunstmann, Harald

    2017-07-01

    The temporal multiscale variability of the surface heat fluxes is assessed by the analysis of the turbulent heat and moisture fluxes using the eddy covariance (EC) technique at the TERrestrial ENvironmental Observatories (TERENO) prealpine region. The fast and slow response variables from three EC sites located at Fendt, Rottenbuch, and Graswang are gathered for the period of 2013 to 2014. Here, the main goals are to characterize the multiscale variations and drivers of the turbulent fluxes, as well as to quantify the energy balance closure (EBC) and analyze the possible reasons for the lack of EBC at the EC sites. To achieve these goals, we conducted a principal component analysis (PCA) and a climatological turbulent flux footprint analysis. The results show significant differences in the mean diurnal variations of the sensible heat (H) and latent heat (LE) fluxes, because of variations in the solar radiation, precipitation patterns, soil moisture, and the vegetation fraction throughout the year. LE was the main consumer of net radiation. Based on the first principal component (PC1), the radiation and temperature components with a total mean contribution of 29.5 and 41.3%, respectively, were found to be the main drivers of the turbulent fluxes at the study EC sites. A general lack of EBC is observed, where the energy imbalance values amount 35, 44, and 35% at the Fendt, Rottenbuch, and Graswang sites, respectively. An average energy balance ratio (EBR) of 0.65 is obtained in the region. The best closure occurred in the afternoon peaking shortly before sunset with a different pattern and intensity between the study sites. The size and shape of the annual mean half-hourly turbulent flux footprint climatology was analyzed. On average, 80% of the flux footprint was emitted from a radius of approximately 250 m around the EC stations. Moreover, the overall shape of the flux footprints was in good agreement with the prevailing wind direction for all three TERENO EC sites.

  13. A balanced filterless K-edge energy window multilayer detector for dual energy computed tomography

    Science.gov (United States)

    Allec, Nicholas; Karim, Karim S.

    2010-04-01

    Ross (or balanced) filter-based systems have been studied extensively in the past, however they have only recently been studied for medical applications such as computed tomography and contrast-enhanced mammography. Balanced filters are filters composed of different materials which have thicknesses designed to match the attenuation for all radiation energies except those within a certain energy window (between the K-edges of the filter materials). Images obtained using different filters to attenuate the incident x-rays can be subtracted to obtain an image which contains information solely within the energy window. The disadvantage of this image acquisition method is the requirement of a separate exposure for each filter. This can lead to motion artifacts in the resulting image for example due to cardiac, respiratory, or patient movement. In this paper we investigate a filterless, multilayer detector design using the general concept of balanced filters. In the proposed detector, energy discrimination is achieved using stacked layers of different conversion materials. Similar to how the thicknesses of balanced filters are chosen, the thicknesses of the conversion layers are designed to match the attenuation of x-rays except between the K-edges of the conversion materials. Motion artifacts are suppressed in the final image due to the simultaneous acquisition of images on all layers during a single exposure. The proposed multilayer design can be used for a number of applications depending on the energy range of interest. To study the proposed design, we consider dual energy computed tomography (CT) using a gadolinium-based contrast agent.

  14. Energy efficiency based joint cell selection and power allocation scheme for HetNets

    Directory of Open Access Journals (Sweden)

    Kwabena Kobia Mensah

    2016-11-01

    Full Text Available Heterogeneous networks (HetNets composed of overlapped cells with different sizes are expected to improve the transmission performance of data service significantly. User equipments (UEs in the overlapped area of multiple cells might be able to access various base stations (BSs of the cells, resulting in various transmission performances due to cell heterogeneity. Hence, designing optimal cell selection scheme is of particular importance for it may affect user quality of service (QoS and network performance significantly. In this paper, we jointly consider cell selection and transmit power allocation problem in a HetNet consisting of multiple cells. For a single UE case, we formulate the energy efficiency of the UE, and propose an energy efficient optimization scheme which selects the optimal cell corresponding to the maximum energy efficiency of the UE. The problem is then extended to multiple UEs case. To achieve joint performance optimization of all the UEs, we formulate an optimization problem with the objective of maximizing the sum energy efficiency of UEs subject to QoS and power constraints. The formulated nonlinear fractional optimization problem is equivalently transformed into two subproblems, i.e., power allocation subproblem of each UE-cell pair, and cell selection subproblem of UEs. The two subproblems are solved respectively through applying Lagrange dual method and Kuhn–Munkres (K-M algorithm. Numerical results demonstrate the efficiency of the proposed algorithm.

  15. Energy balance for Sachsen-Anhalt 2010; Energiebilanz Sachsen-Anhalt 2010

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2013-01-15

    The energy balance of Saxony-Anhalt is presented in physical units, in terrajoule and in coal equivalent to show supply, conversion, and consumption of primary and secondary energy sources in the year under report 2010 Energy balance for Sachsen-Anhalt.

  16. Soil Moisture and Vegetation Controls on Surface Energy Balance Using the Maximum Entropy Production Model of Evapotranspiration

    Science.gov (United States)

    Wang, J.; Parolari, A.; Huang, S. Y.

    2014-12-01

    The objective of this study is to formulate and test plant water stress parameterizations for the recently proposed maximum entropy production (MEP) model of evapotranspiration (ET) over vegetated surfaces. . The MEP model of ET is a parsimonious alternative to existing land surface parameterizations of surface energy fluxes from net radiation, temperature, humidity, and a small number of parameters. The MEP model was previously tested for vegetated surfaces under well-watered and dry, dormant conditions, when the surface energy balance is relatively insensitive to plant physiological activity. Under water stressed conditions, however, the plant water stress response strongly affects the surface energy balance. This effect occurs through plant physiological adjustments that reduce ET to maintain leaf turgor pressure as soil moisture is depleted during drought. To improve MEP model of ET predictions under water stress conditions, the model was modified to incorporate this plant-mediated feedback between soil moisture and ET. We compare MEP model predictions to observations under a range of field conditions, including bare soil, grassland, and forest. The results indicate a water stress function that combines the soil water potential in the surface soil layer with the atmospheric humidity successfully reproduces observed ET decreases during drought. In addition to its utility as a modeling tool, the calibrated water stress functions also provide a means to infer ecosystem influence on the land surface state. Challenges associated with sampling model input data (i.e., net radiation, surface temperature, and surface humidity) are also discussed.

  17. Intraseasonal Variations in Tropical Energy Balance: Relevance to Climate Sensitivity?

    Science.gov (United States)

    Robertson, Franklin R.; Ramey, Holly S.; Roberts, Jason B.

    2011-01-01

    Intraseasonal variability of deep convection represents a fundamental mode of organization for tropical convection. While most studies of intraseasonal oscillations (ISOs) have focused on the spatial propagation and dynamics of convectively coupled circulations, here we examine the projection of ISOs on the tropically-averaged heat and moisture budget. One unresolved question concerns the degree to which observable variations in the "fast" processes (e.g. convection, radiative / turbulent fluxes) can inform our understanding of feedback mechanisms operable in the context of climate change. Our analysis use daily data from satellite observations, the Modern Era analysis for Research and Applications (MERRA), and other model integrations to address these questions: (i) How are tropospheric temperature variations related to that tropical deep convection and the associated ice cloud fractional amount (ICF), ice water path (IWP), and properties of warmer liquid clouds? (ii) What role does moisture transport play vis-a-vis ocean latent heat flux in enabling the evolution of deep convection to mediate PBL - free atmospheric temperature equilibration? (iii) What affect do convectively generated upper-tropospheric clouds have on the TOA radiation budget? Our methodology is similar to that of Spencer et al., (2007 GRL ) whereby a composite time series of various quantities over 60+ ISO events is built using tropical mean tropospheric temperature signal as a reference to which the variables are related at various lag times (from -30 to +30 days). The area of interest encompasses the global oceans between 20oN/S. The increase of convective precipitation cannot be sustained by evaporation within the domain, implying strong moisture transports into the tropical ocean area. The decrease in net TOA radiation that develops after the peak in deep convective rainfall, is part of the response that constitutes a "discharge" / "recharge" mechanism that facilitates tropical heat balance

  18. Comparison of the meteorology and surface energy balance at Storbreen and Midtdalsbreen, two glaciers in southern Norway

    Directory of Open Access Journals (Sweden)

    R. H. Giesen

    2009-03-01

    Full Text Available We compare 5 years of meteorological records from automatic weather stations (AWSs on Storbreen and Midtdalsbreen, two glaciers in southern Norway, located approximately 120 km apart. The records are obtained from identical AWSs with an altitude difference of 120 m and cover the period September 2001 to September 2006. Air temperature at the AWS locations is found to be highly correlated, even with the seasonal cycle removed. The most striking difference between the two sites is the difference in wind climate. Midtdalsbreen is much more under influence of the large-scale circulation with wind speeds on average a factor 1.75 higher. On Storbreen, weaker katabatic winds are dominant. The main melt season is from May to September at both locations. During the melt season, incoming and net solar radiation are larger on Midtdalsbreen, whereas incoming and net longwave radiation are larger on Storbreen, primarily caused by thicker clouds on the latter. The turbulent fluxes are a factor 1.7 larger on Midtdalsbreen, mainly due to the higher wind speeds. Inter-daily fluctuations in the surface energy fluxes are very similar at the AWS sites. On average, melt energy is a factor 1.3 larger on Midtdalsbreen, a result of both larger net radiation and larger turbulent fluxes. The relative contribution of net radiation to surface melt is larger on Storbreen (76% than on Midtdalsbreen (66%. As winter snow depth at the two locations is comparable in most years, the larger amount of melt energy results in an earlier disappearance of the snowpack on Midtdalsbreen and 70% more ice melt than on Storbreen. We compare the relative and absolute values of the energy fluxes on Storbreen and Midtdalsbreen with reported values for glaciers at similar latitudes. Furthermore, a comparison is made with meteorological variables measured at two nearby weather stations, showing that on-site measurements are essential for an accurate calculation of the surface energy balance and

  19. A distributed energy-balance melt model of an alpine debris-covered glacier

    OpenAIRE

    Fyffe, Catriona; Reid, Tim; Brock, Benjamin; Kirkbride, Martin; Diolaiuti, Guglielmina; Smiraglia, Claudio; Diotri, Fabrizio

    2014-01-01

    Distributed energy-balance melt models have rarely been applied to glaciers with extensive supraglacial debris cover. This paper describes the development of a distributed melt model and its application to the debris-covered Miage glacier, western Italian Alps, over two summer seasons. Sub-debris melt rates are calculated using an existing debris energy-balance model (DEB-Model), and melt rates for clean ice, snow and partially debris-covered ice are calculated using standard energy-balance e...

  20. Current trends in targeting the hormonal regulation of appetite and energy balance to treat obesity

    OpenAIRE

    Valentino, Michael A; Colon-Gonzalez, Francheska; Lin, Jieru E.; Waldman, Scott A.

    2010-01-01

    With the eruption of the obesity pandemic over the past few decades, much research has been devoted to understanding the molecular mechanisms by which the human body regulates energy balance. These studies have revealed several mediators, including gut/pancreatic/adipose hormones and neuropeptides that control both short- and long-term energy balance by regulating appetite and/or metabolism. These endogenous mediators of energy balance have been the focus of many anti-obesity drug-development...

  1. Scheduling algorithms for saving energy and balancing load

    Energy Technology Data Exchange (ETDEWEB)

    Antoniadis, Antonios

    2012-08-03

    In this thesis we study problems of scheduling tasks in computing environments. We consider both the modern objective function of minimizing energy consumption, and the classical objective of balancing load across machines. We first investigate offline deadline-based scheduling in the setting of a single variable-speed processor that is equipped with a sleep state. The objective is that of minimizing the total energy consumption. Apart from settling the complexity of the problem by showing its NP-hardness, we provide a lower bound of 2 for general convex power functions, and a particular natural class of schedules called s{sub crit}-schedules. We also present an algorithmic framework for designing good approximation algorithms. For general convex power functions our framework improves the best known approximation-factor from 2 to 4/3. This factor can be reduced even further to 137/117 for a specific well-motivated class of power functions. Furthermore, we give tight bounds to show that our framework returns optimal s{sub crit}-schedules for the two aforementioned power-function classes. We then focus on the multiprocessor setting where each processor has the ability to vary its speed. Job migration is allowed, and we again consider classical deadline-based scheduling with the objective of energy minimization. We first study the offline problem and show that optimal schedules can be computed efficiently in polynomial time for any convex and non-decreasing power function. Our algorithm relies on repeated maximum flow computations. Regarding the online problem and power functions P(s) = s{sup {alpha}}, where s is the processor speed and {alpha} > 1 a constant, we extend the two well-known single-processor algorithms Optimal Available and Average Rate. We prove that Optimal Available is {alpha}{sup {alpha}}-competitive as in the single-processor case. For Average Rate we show a competitive factor of (2{alpha}){sup {alpha}}/2 + 1, i.e., compared to the single

  2. Prediction of net energy consumption based on economic indicators (GNP and GDP) in Turkey

    Energy Technology Data Exchange (ETDEWEB)

    Soezen, Adnan [Technical Education Faculty, Mechanical Education Department, Energy Section, Gazi University, 06500 Teknikokullar, Ankara (Turkey); Arcaklioglu, Erol [Engineering Faculty, Mechanical Engineering Department, Kirikkale University, 71450 Kirikkale (Turkey)

    2007-10-15

    The most important theme in this study is to obtain equations based on economic indicators (gross national product - GNP and gross domestic product - GDP) and population increase to predict the net energy consumption of Turkey using artificial neural networks (ANNs) in order to determine future level of the energy consumption and make correct investments in Turkey. In this study, three different models were used in order to train the ANN. In one of them (Model 1), energy indicators such as installed capacity, generation, energy import and energy export, in second (Model 2), GNP was used and in the third (Model 3), GDP was used as the input layer of the network. The net energy consumption (NEC) is in the output layer for all models. In order to train the neural network, economic and energy data for last 37 years (1968-2005) are used in network for all models. The aim of used different models is to demonstrate the effect of economic indicators on the estimation of NEC. The maximum mean absolute percentage error (MAPE) was found to be 2.322732, 1.110525 and 1.122048 for Models 1, 2 and 3, respectively. R{sup 2} values were obtained as 0.999444, 0.999903 and 0.999903 for training data of Models 1, 2 and 3, respectively. The ANN approach shows greater accuracy for evaluating NEC based on economic indicators. Based on the outputs of the study, the ANN model can be used to estimate the NEC from the country's population and economic indicators with high confidence for planing future projections. (author)

  3. The Global Energy Balance Archive (GEBA): A database for the worldwide measured surface energy fluxes

    Science.gov (United States)

    Wild, Martin; Ohmura, Atsumu; Schär, Christoph; Müller, Guido; Hakuba, Maria Z.; Mystakidis, Stefanos; Arsenovic, Pavle; Sanchez-Lorenzo, Arturo

    2017-02-01

    The Global Energy Balance Archive (GEBA) is a database for the worldwide measured energy fluxes at the Earth's surface. GEBA is maintained at ETH Zurich (Switzerland) and has been founded in the 1980s by Prof. Atsumu Ohmura. It has continuously been updated and currently contains around 2500 stations with 500`000 monthly mean entries of various surface energy balance components. Many of the records extend over several decades. The most widely measured quantity available in GEBA is the solar radiation incident at the Earth's surface ("global radiation"). The data sources include, in addition to the World Radiation Data Centre (WRDC) in St. Petersburg, data reports from National Weather Services, data from different research networks (BSRN, ARM, SURFRAD), data published in peer-reviewed publications and data obtained through personal communications. Different quality checks are applied to check for gross errors in the dataset. GEBA is used in various research applications, such as for the quantification of the global energy balance and its spatiotemporal variation, or for the estimation of long-term trends in the surface fluxes, which enabled the detection of multi-decadal variations in surface solar radiation, known as "global dimming" and "brightening". GEBA is further extensively used for the evaluation of climate models and satellite-derived surface flux products. On a more applied level, GEBA provides the basis for engineering applications in the context of solar power generation, water management, agricultural production and tourism. GEBA is publicly accessible over the internet via www.geba.ethz.ch.

  4. Maximizing Residential Energy Savings: Net Zero Energy House (ZEH) Technology Pathways

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, R.; Roberts, D.

    2008-11-01

    To meet current U.S. Department of Energy zero-energy home performance goals, new technologies and solutions must increase whole-house efficiency savings by an additional 40% relative to those provided by best available components and systems.

  5. Summer energy balance and ablation of high elevation glaciers in the central Chilean Andes

    Science.gov (United States)

    Brock, Benjamin; Rivera, Andres; Burger, Flavia; Bravo, Claudio

    2014-05-01

    sublimation, 2.16 m melt). The surface energy balance is dominated by shortwave radiation, which is the only net energy input, apart from a minor contribution from sensible heat, while the main outputs of energy are net longwave radiation, melt and sublimation. Ablation is dominated by melt during the warmer midsummer months at the two AWS sites, with mean rates exceeding 30 mm w.e. per day. However, due to the high latent heat of sublimation, it is only in January and February that the melt energy flux clearly exceeds the sublimation energy flux. Sublimation rates are typically ~1 mm w.e. per day and are 50 to 100 % higher at Olivares Beta as a result of higher wind speed and surface temperature, despite similar air temperatures at the two sites. Melt rates are around twice as high in summer months with mean air temperature > -2° C, compared with cooler months. This implies that future atmospheric warming will accelerate shrinkage of these glaciers as the ablation regime switches increasingly from sublimation to a more efficient melt regime.

  6. Energy partitioning in dairy cows : effects of lipogenic and glucogenic diets on energy balance, metabolites and reproduction variables in early lactation

    NARCIS (Netherlands)

    Knegsel, van A.T.M.

    2007-01-01

    Keywords: dairy cows; dietary energy source; glucogenic nutrients; lipogenic nutrients; negative energy balance; metabolic disorders; reproduction, immune system   Dairy cows experience a negative energy balance (NEB) in early lactation which results from high energy requirements for milk production

  7. Forest Surface Energy Balance and Evapotranspiration Estimated From Four Eddy Covariance Towers

    Science.gov (United States)

    Rabbani, G. A.; Adam, J. C.; Elliot, W. J.; Liu, H.

    2016-12-01

    Evapotranspiration (ET), which refers to the combined effect of surface water evaporation and plant transpiration, is one of the vital elements of the global water balance. It is also an important process for plants, providing water, nutrient, and cooling needs, and helping to regulate carbon dioxide entry through open/closure of the plant's stomata. Quantifying ET in forested environments is an ongoing research area. Complex physiological responses with climatic variation, combined with difficulty in making wide-spread measurements, makes ET one of the least understood components of a forest water balance. The objective of this study is to estimate ET and energy balance closure by using flux net data from eddy covariance towers. ET is estimated for different forest types with multiple age classes during the years of 2011, 2012 and 2013. We studied two coniferous forests (F1, F2), one deciduous forest (F3) and one mixed forest (F4) in Washington, Wyoming, Wisconsin and New Jersey, respectively. Label 2 (Data checked and formatted by Carbon Dioxide Information Analysis Center) gap filled flux data were collected from the AmeriFlux database (ameriflux.ornl.gov). Discrepancies between turbulent fluxes and available energy are investigated. Among the studied forests, the highest and lowest average monthly ET are exhibited by the mixed forest (F4) and coniferous forest (F1) in 2012 which are 2,692 and 633 mm/month, respectively. Difference in average monthly ET can be an implication of substantial age difference between these two types of forest. The regression analysis showed significant correlation between turbulent fluxes and available energy (R2=0.91) for mixed forest where the discrepancy varied from 5-11%. Conversely, for coniferous and deciduous forests, the discrepancy varied from 46-49% and 28%, respectively, with almost similar correlation between the fluxes (0.86 and 0.84, respectively). This study will facilitate an improved understanding of how forest type

  8. Sex effects on net protein and energy requirements for growth of Saanen goats.

    Science.gov (United States)

    Souza, A P; St-Pierre, N R; Fernandes, M H R M; Almeida, A K; Vargas, J A C; Resende, K T; Teixeira, I A M A

    2017-06-01

    Requirements for growth in the different sexes remain poorly quantified in goats. The objective of this study was to develop equations for estimating net protein (NP G ) and net energy (NE G ) for growth in Saanen goats of different sexes from 5 to 45 kg of body weight (BW). A data set from 7 comparative slaughter studies (238 individual records) of Saanen goats was used. Allometric equations were developed to determine body protein and energy contents in the empty BW (EBW) as dependent variables and EBW as the allometric predictor. Parameter estimates were obtained using a linearized (log-transformation) expression of the allometric equations using the MIXED procedure in SAS software (SAS Institute Inc., Cary, NC). The model included the random effect of the study and the fixed effects of sex (intact male, castrated male, and female; n = 94, 73, and 71, respectively), EBW, and their interactions. Net requirements for growth were estimated as the first partial derivative of the allometric equations with respect to EBW. Additionally, net requirements for growth were evaluated based on the degree of maturity. Monte Carlo techniques were used to estimate the uncertainty of the calculated net requirement values. Sex affected allometric relationships for protein and energy in Saanen goats. The allometric equation for protein content in the EBW of intact and castrated males was log 10 protein (g) = 2.221 (±0.0224) + 1.015 (±0.0165) × log 10 EBW (kg). For females, the relationship was log 10 protein (g) = 2.277 (±0.0288) + 0.958 (±0.0218) × log 10 EBW (kg). Therefore, NP G for males was greater than for females. The allometric equation for the energy content in the EBW of intact males was log 10 energy (kcal) = 2.988 (±0.0323) + 1.240 (±0.0238) × log 10 EBW (kg); of castrated males, log 10 energy (kcal) = 2.873 (±0.0377) + 1.359 (±0.0283) × log 10 EBW (kg); and of females, log 10 energy (kcal) = 2.820 (±0.0377) + 1.442 (±0.0281) × log 10 EBW (kg). The NE G

  9. Ion-kinetic-energy measurements and energy balance in a Z-pinch plasma at stagnation.

    Science.gov (United States)

    Kroupp, E; Osin, D; Starobinets, A; Fisher, V; Bernshtam, V; Maron, Y; Uschmann, I; Förster, E; Fisher, A; Deeney, C

    2007-03-16

    The ion-kinetic energy throughout K emission in a stagnating plasma was determined from the Doppler contribution to the shapes of optically thin lines. X-ray spectroscopy with a remarkably high spectral resolution, together with simultaneous imaging along the pinch, was employed. Over the emission period, a drop of the ion-kinetic energy down to the electron thermal energy was seen. Axially resolved time-dependent electron-density measurements and absolute intensities of line and continuum allowed for investigating, for the first time, each segment of the pinch, the balance between the ion-kinetic energy at the stagnating plasma, and the total radiation emitted. Within the experimental uncertainties, the ion-kinetic energy is shown to account for the total radiation.

  10. Quantifying the role of fire in the Earth system - Part 2: Impact on the net carbon balance of global terrestrial ecosystems for the 20th century

    Energy Technology Data Exchange (ETDEWEB)

    Li, Fang; Bond-Lamberty, Benjamin; Levis, Samuel

    2014-03-07

    Fire is the primary terrestrial ecosystem disturbance agent on a global scale. It affects carbon balance of global terrestrial ecosystems by emitting carbon to atmosphere directly and immediately from biomass burning (i.e., fire direct effect), and by changing net ecosystem productivity and land-use carbon loss in post-fire regions due to biomass burning and fire-induced vegetation mortality (i.e., fire indirect effect). Here, we provide the first quantitative assessment about the impact of fire on the net carbon balance of global terrestrial ecosystems for the 20th century, and investigate the roles of fire direct and indirect effects. This study is done by quantifying the difference between the 20th century fire-on and fire-off simulations with NCAR community land model CLM4.5 as the model platform. Results show that fire decreases net carbon gain of the global terrestrial ecosystems by 1.0 Pg C yr-1 average across the 20th century, as a results of fire direct effect (1.9 Pg C yr-1) partly offset by indirect effect (-0.9 Pg C yr-1). Fire generally decreases the average carbon gains of terrestrial ecosystems in post-fire regions, which are significant over tropical savannas and part of forests in North America and the east of Asia. The general decrease of carbon gains in post-fire regions is because fire direct and indirect effects have similar spatial patterns and the former (to decrease carbon gain) is generally stronger. Moreover, the effect of fire on net carbon balance significantly declines prior to ~1970 with trend of 8 Tg C yr-1 due to increasing fire indirect effect and increases afterward with trend of 18 Tg C yr-1 due to increasing fire direct effect.

  11. Beyond Leptin: Emerging Candidates for the Integration of Metabolic and Reproductive Function during Negative Energy Balance.

    Science.gov (United States)

    True, Cadence; Grove, Kevin L; Smith, M Susan

    2011-01-01

    Reproductive status is tightly coupled to metabolic state in females, and ovarian cycling in mammals is halted when energy output exceeds energy input, a metabolic condition known as negative energy balance. This inhibition of reproductive function during negative energy balance occurs due to suppression of gonadotropin-releasing hormone (GnRH) release in the hypothalamus. The GnRH secretagogue kisspeptin is also inhibited during negative energy balance, indicating that inhibition of reproductive neuroendocrine circuits may occur upstream of GnRH itself. Understanding the metabolic signals responsible for the inhibition of reproductive pathways has been a compelling research focus for many years. A predominant theory in the field is that the status of energy balance is conveyed to reproductive neuroendocrine circuits via the adipocyte hormone leptin. Leptin is stimulatory for GnRH release and lower levels of leptin during negative energy balance are believed to result in decreased stimulatory drive for GnRH cells. However, recent evidence found that restoring leptin to physiological levels did not restore GnRH function in three different models of negative energy balance. This suggests that although leptin may be an important permissive signal for reproductive function as indicated by many years of research, factors other than leptin must critically contribute to negative energy balance-induced reproductive inhibition. This review will focus on emerging candidates for the integration of metabolic status and reproductive function during negative energy balance.

  12. Effect of synthetic surfaces and vegetation in urban areas on human energy balance and comfort

    Science.gov (United States)

    Thomas F. Stark; David R. Miller

    1977-01-01

    The thermal balance of a standard man was quantified for a variety of urban and rural summer daytime microclimates. The resulting net heat-load data were correlated with the relative amounts of vegetation and synthetic materials at each site. By extrapolating these results, it is possible to estimate the expected heat load of a proposed development before it is built...

  13. Sustainable Skyscrapers: Designing the Net Zero Energy Building of the Future

    Science.gov (United States)

    Kothari, S.; Bartsch, A.

    2016-12-01

    Cities of the future will need to increase population density in order to keep up with the rising populations in the limited available land area. In order to provide sufficient power as the population grows, cities must become more energy efficient. Fossil fuels and grid energy will continue to become more expensive as nonrenewable resources deplete. The obvious solution to increase population density while decreasing the reliance on fossil fuels is to build taller skyscrapers that are energy neutral, i.e. self-sustaining. However, current skyscrapers are not energy efficient, and therefore cannot provide a sustainable solution to the problem of increasing population density in the face of depleting energy resources. The design of a net zero energy building that includes both residential and commercial space is presented. Alternative energy systems such as wind turbines, photovoltaic cells, and a waste-to-fuel conversion plant have been incorporated into the design of a 50 story skyscraper that is not reliant on fossil fuels and has a payback time of about six years. Although the current building was designed to be located in San Francisco, simple modifications to the design would allow this building to fit the needs of any city around the world.

  14. METHODS FOR OPTIMIZING ENERGY BALANCE IN OVERWEIGHT PEOPLE

    Directory of Open Access Journals (Sweden)

    Malakhova Tatyana Vladimirovna

    2013-06-01

    Full Text Available The article proposes a new approach to solving the problem of overweight and obesity based on the optimization of the energy balance in the body, using the technologies applied in industrial heat power devices. The main task during the formation of the diet is to ensure a steady, moderate and long-term supply of glucose into the blood stream, avoiding one-time drastic jumps in blood sugar levels. The proposed method of weight loss was tested among 46-52 years old women with the excess weight, prone to obesity. The control weighing was performed every 7 days. The study period was 60 weeks. Proper regulation of food composition and “fuel injection” rhythm, optimum from the point of view of thermal technology, allows using “negative calorie effect” against the background of the overall revitalization of metabolic processes. From the first weeks of the application of the proposed method of weight loss a significant reduction in body weight was mathematically observed. An important prerequisite for the success of the method is the correct order of food intake.

  15. Interactions between negative energy balance, metabolic diseases, uterine health and immune response in transition dairy cows.

    Science.gov (United States)

    Esposito, Giulia; Irons, Pete C; Webb, Edward C; Chapwanya, Aspinas

    2014-01-30

    The biological cycles of milk production and reproduction determine dairying profitability thus making management decisions dynamic and time-dependent. Diseases also negatively impact on net earnings of a dairy enterprise. Transition cows in particular face the challenge of negative energy balance (NEB) and/or disproportional energy metabolism (fatty liver, ketosis, subacute, acute ruminal acidosis); disturbed mineral utilization (milk fever, sub-clinical hypocalcemia); and perturbed immune function (retained placenta, metritis, mastitis). Consequently NEB and reduced dry matter intake are aggravated. The combined effects of all these challenges are reduced fertility and milk production resulting in diminishing profits. Risk factors such as NEB, inflammation and impairment of the immune response are highly cause-and-effect related. Thus, managing cows during the transition period should be geared toward reducing NEB or feeding specially formulated diets to improve immunity. Given that all cows experience a reduced feed intake and body condition, infection and inflammation of the uterus after calving, there is a need for further research on the immunology of transition dairy cows. Integrative approaches at the molecular, cellular and animal level may unravel the complex interactions between disturbed metabolism and immune function that predispose cows to periparturient diseases. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. Assessing the impacts of changes in treatment technology on energy and greenhouse gas balances for organic waste and wastewater treatment using historical data.

    Science.gov (United States)

    Poulsen, Tjalfe G; Hansen, Jens Aage

    2009-11-01

    Historical data on organic waste and wastewater treatment during the period of 1970-2020 were used to assess the impact of treatment on energy and greenhouse gas (GHG) balances. The assessment included the waste fractions: Sewage sludge, food waste, yard waste and other organic waste (paper, plastic, etc.). Data were collected from Aalborg, a municipality located in Northern Denmark. During the period from 1970-2005, Aalborg Municipality has changed its waste treatment strategy from landfilling of all wastes toward composting of yard waste and incineration with combined heat and power production from the remaining organic municipal waste. Wastewater treatment has changed from direct discharge of untreated wastewater to full organic matter and nutrient (N, P) removal combined with anaerobic digestion of the sludge for biogas production with power and heat generation. These changes in treatment technology have resulted in the waste and wastewater treatment systems in Aalborg progressing from being net consumers of energy and net emitters of GHG, to becoming net producers of energy and net savers of GHG emissions (due to substitution of fossil fuels elsewhere). If it is assumed that the organic waste quantity and composition is the same in 1970 and 2005, the technology change over this time period has resulted in a progression from a net annual GHG emission of 200 kg CO( 2)-eq. capita(-1) in 1970 to a net saving of 170 kg CO(2)-eq. capita(-1) in 2005 for management of urban organic wastes.

  17. Importance of Soil Moisture and Vegetation Cover for Energy Balance partition in Burkina Faso

    Science.gov (United States)

    Ceperley, N. C.; Mande, T.; Tyler, S. W.; Bou-Zeid, E.; Van De Giesen, N.; Parlange, M. B.

    2015-12-01

    Land surface characteristics are the main control on hydrologic processes, the driver of most livelihoods, in semi arid West Africa. We use the energy and water balance measured with two eddy-covariance towers, coupled with a dense network of small, wireless meteorological stations in a small (3.5 km2) catchment to understand these relationships. Time series of monthly averages of soil moisture, rainfall, air temperature, cloud cover, components of net radiation, wind speed, and NDVI are presented in relation to the evaporative fraction and energy balance. We found that both latent and sensible heat fluxes are greater over mixed forest and savanna areas compared agricultural land. Sensible heat is found to be most different between the two land-covers at the end of the year, when the grass and vegetation is dry, and latent heat is found to be most different at the beginning of the year, when bare ground dominates. Further examination shows that soil moisture and vegetation indexes provide the main controls on evaporative fraction. These findings have implications for modeling the evaporation over large regions based on remotely sensed land surface temperature. The site is characteristic of the contrasts in vegetation and moisture availability present in the rocky escarpments found in Northern Benin and Southeastern Burkina Faso. Historically these sites are important in location for village choice and land use designation. These findings reinforce local cultural beliefs of the importance of vegetation for climate regulation and may provide support to local farmers for improving the resilience of natural resources and livelihood security.

  18. Potential evaporation estimation through an unstressed surface energy balance and its sensitivity to climate change

    Science.gov (United States)

    Barella-Ortiz, A.; Polcher, J.; Tuzet, A.; Laval, K.

    2013-06-01

    Potential evaporation (ETP) is a basic input for hydrological and agronomic models, as well as a key variable in most actual evaporation estimations. It has been approached through several diffusive and energy balance methods, out of which the Penman-Monteith equation is recommended as the standard one. In order to deal with the diffusive approach, ETP must be estimated at a sub-diurnal frequency, as currently done in land surface models (LSM). This study presents an improved method, developed in the ORCHIDEE LSM, which consists in estimating ETP through an unstressed surface energy balance (USEB method). The results confirm the quality of the estimation which is currently implemented in the model (Milly, 1992). ETP has also been estimated using a reference equation (computed at a daily time step) provided by the Food and Agriculture Organization (FAO). First, a comparison for a reference period under current climate conditions, shows that both formulations differ, specially in arid areas. However, they supply similar values when FAO's assumption of neutral stability conditions is relaxed, by replacing FAO's aerodynamic resistance by the model's one. Furthermore, if the vapour pressure deficit (VPD) estimated for FAO's equation, is substituted by ORCHIDEE's VPD or its humidity gradient, the daily mean estimate is further improved. In a second step, ETP's sensitivity to climate change is assessed comparing trends in both formulations for the 21st Century. It is found that the USEB method shows a higher sensitivity. Both VPD and the model's humidity gradient, as well as the aerodynamic resistance have been identified as key parameters in governing ETP trends. Finally, the sensitivity study is extended to three empirical approximations based on temperature, net radiation and mass transfer (Hargreaves, Priestley-Taylor and Rohwer, respectively). The sensitivity of these methods is compared to the USEB method's one to test if simplified equations are able to reproduce

  19. Energy self-reliance, net-energy production and GHG emissions in Danish organic cash crop farms

    DEFF Research Database (Denmark)

    Halberg, Niels; Dalgaard, Randi; Olesen, Jørgen E

    2008-01-01

    -energy production were modeled. Growing rapeseed on 10% of the land could produce bio-diesel to replace 50-60% of the tractor diesel used on the farm. Increasing grass-clover area to 20% of the land and using half of this yield for biogas production could change the cash crop farm to a net energy producer......Organic farming (OF) principles include the idea of reducing dependence of fossil fuels, but little has been achieved on this objective so far in Danish OF. Energy use and greenhouse gas (GHG) emissions from an average 39 ha cash crop farm were calculated and alternative crop rotations for bio......, and reduce GHG emissions while reducing the overall output of products only marginally. Increasing grass-clover area would improve the nutrient management on the farm and eliminate dependence on conventional pig slurry if the biogas residues were returned to cash crop fields...

  20. Energy Consumption and Saving Analysis for Laser Engineered Net Shaping of Metal Powders

    Directory of Open Access Journals (Sweden)

    Zhichao Liu

    2016-09-01

    Full Text Available With the increasing awareness of environmental protection and sustainable manufacturing, the environmental impact of laser additive manufacturing (LAM technology has been attracting more and more attention. Aiming to quantitatively analyze the energy consumption and extract possible ways to save energy during the LAM process, this investigation studies the effects of input variables including laser power, scanning speed, and powder feed rate on the overall energy consumption during the laser deposition processes. Considering microhardness as a standard quality, the energy consumption of unit deposition volume (ECUDV, in J/mm3 is proposed as a measure for the average applied energy of the fabricated metal part. The potential energy-saving benefits of the ultrasonic vibration–assisted laser engineering net shaping (LENS process are also examined in this paper. The experimental results suggest that the theoretical and actual values of the energy consumption present different trends along with the same input variables. It is possible to reduce the energy consumption and, at the same time, maintain a good part quality and the optimal combination of the parameters referring to Inconel 718 as a material is laser power of 300 W, scanning speed of 8.47 mm/s and powder feed rate of 4 rpm. When the geometry shaping and microhardness are selected as evaluating criterions, American Iron and Steel Institute (AISI 4140 powder will cause the largest energy consumption per unit volume. The ultrasonic vibration–assisted LENS process cannot only improve the clad quality, but can also decrease the energy consumption to a considerable extent.

  1. Towards a Sustainable Energy Balance: Progressive Efficiency and the Return of Energy Conservation

    Energy Technology Data Exchange (ETDEWEB)

    Diamond, Rick; Harris, Jeff; Diamond, Rick; Iyer, Maithili; Payne, Christopher; Blumstein, Carl; Siderius, Hans-Paul

    2007-08-13

    We argue that a primary focus on energy efficiency may not be sufficient to slow (and ultimately reverse) the growth in total energy consumption and carbon emissions. Instead, policy makers need to return to an earlier emphasis on"conservation," with energy efficiency seen as a means rather than an end in itself. We briefly review the concept of"intensive" versus"extensive" variables (i.e., energy efficiency versus energy consumption), and why attention to both consumption and efficiency is essential for effective policy in a carbon- and oil-constrained world with increasingly brittle energy markets. To start, energy indicators and policy evaluation metrics need to reflect energy consumption as well as efficiency. We introduce the concept of"progressive efficiency," with the expected or required level of efficiency varying as a function of house size, appliance capacity, or more generally, the scale of energy services. We propose introducing progressive efficiency criteria first in consumer information programs (including appliance labeling categories) and then in voluntary rating and recognition programs such as ENERGY STAR. As acceptance grows, the concept could be extended to utility rebates, tax incentives, and ultimately to mandatory codes and standards. For these and other programs, incorporating criteria for consumption as well as efficiency offers a path for energy experts, policy-makers, and the public to begin building consensus on energy policies that recognize the limits of resources and global carrying-capacity. Ultimately, it is both necessary and, we believe, possible to manage energy consumption, not just efficiency in order to achieve a sustainable energy balance. Along the way, we may find it possible to shift expectations away from perpetual growth and toward satisfaction with sufficiency.

  2. Surface layer scintillometry for estimating the sensible heat flux component of the surface energy balance

    Directory of Open Access Journals (Sweden)

    M. J. Savage

    2010-01-01

    energy balance, measurements of net irradiance and soil heat as well as SLS estimates of sensible heat allows path-weighted evaporation from the surface to be estimated. Research applications involving the use of the SLS method, as well as the theory on which the method is based, are presented.

  3. The urban energy balance of a lightweight low-rise neighborhood in Andacollo, Chile

    Science.gov (United States)

    Crawford, Ben; Krayenhoff, E. Scott; Cordy, Paul

    2018-01-01

    Worldwide, the majority of rapidly growing neighborhoods are found in the Global South. They often exhibit different building construction and development patterns than the Global North, and urban climate research in many such neighborhoods has to date been sparse. This study presents local-scale observations of net radiation ( Q * ) and sensible heat flux ( Q H ) from a lightweight low-rise neighborhood in the desert climate of Andacollo, Chile, and compares observations with results from a process-based urban energy-balance model (TUF3D) and a local-scale empirical model (LUMPS) for a 14-day period in autumn 2009. This is a unique neighborhood-climate combination in the urban energy-balance literature, and results show good agreement between observations and models for Q * and Q H . The unmeasured latent heat flux ( Q E ) is modeled with an updated version of TUF3D and two versions of LUMPS (a forward and inverse application). Both LUMPS implementations predict slightly higher Q E than TUF3D, which may indicate a bias in LUMPS parameters towards mid-latitude, non-desert climates. Overall, the energy balance is dominated by sensible and storage heat fluxes with mean daytime Bowen ratios of 2.57 (observed Q H /LUMPS Q E )-3.46 (TUF3D). Storage heat flux ( ΔQ S ) is modeled with TUF3D, the empirical objective hysteresis model (OHM), and the inverse LUMPS implementation. Agreement between models is generally good; the OHM-predicted diurnal cycle deviates somewhat relative to the other two models, likely because OHM coefficients are not specified for the roof and wall construction materials found in this neighborhood. New facet-scale and local-scale OHM coefficients are developed based on modeled ΔQ S and observed Q * . Coefficients in the empirical models OHM and LUMPS are derived from observations in primarily non-desert climates in European/North American neighborhoods and must be updated as measurements in lightweight low-rise (and other) neighborhoods in

  4. Scoping study for compact high-field superconducting net energy tokamaks

    Science.gov (United States)

    Mumgaard, R. T.; Greenwald, M.; Freidberg, J. P.; Wolfe, S. M.; Hartwig, Z. S.; Brunner, D.; Sorbom, B. N.; Whyte, D. G.

    2016-10-01

    The continued development and commercialization of high temperature superconductors (HTS) may enable the construction of compact, net-energy tokamaks. HTS, in contrast to present generation low temperature superconductors, offers improved performance in high magnetic fields, higher current density, stronger materials, higher temperature operation, and simplified assembly. Using HTS along with community-consensus confinement physics (H98 =1) may make it possible to achieve net-energy (Q>1) or burning plasma conditions (Q>5) in DIII-D or ASDEX-U sized, conventional aspect ratio tokamaks. It is shown that, by operating at high plasma current and density enabled by the high magnetic field (B>10T), the required triple products may be achieved at plasma volumes under 20m3, major radii under 2m, with external heating powers under 40MW. This is at the scale of existing devices operated by laboratories, universities and companies. The trade-offs in the core heating, divertor heat exhaust, sustainment, stability, and proximity to known plasma physics limits are discussed in the context of the present tokamak experience base and the requirements for future devices. The resulting HTS-based design space is compared and contrasted to previous studies on high-field copper experiments with similar missions. The physics exploration conducted with such HTS devices could decrease the real and perceived risks of ITER exploitation, and aid in quickly developing commercially-applicable tokamak pilot plants and reactors.

  5. Transformations, Inc.: Partnering to Build Net-Zero Energy Houses in Massachusetts

    Energy Technology Data Exchange (ETDEWEB)

    Ueno, K. [Building Science Corporation, Somerville, MA (United States); Bergey, D. [Building Science Corporation, Somerville, MA (United States); Wytrykowska, H. [Building Science Corporation, Somerville, MA (United States)

    2013-09-01

    Transformations, Inc. is a residential development and building company that has partnered with Building Science Corporation to build new construction net-zero energy houses in Massachusetts under the Building America program. There are three communities that will be constructed through this partnership: Devens Sustainable Housing ('Devens'), The Homes at Easthampton Meadow ('Easthampton') andPhase II of the Coppersmith Way Development ('Townsend'). This report intends to cover all of the single-family new construction homes that have been completed to date. The houses built in these developments are net zero energy homes built in a cold climate. They will contribute to finding answers to specific research questions for homes with high R double stud walls and high efficiency ductlessair source heat pump systems ('mini-splits'); allow to explore topics related to the financing of photovoltaic systems and basements vs. slab-on-grade construction; and provide feedback related to the performance of ductless mini-split air source heat pumps.

  6. Proposal for a refinement of the National Energy Balance (BEN) and Useful Energy Balance (BEU); Proposta de refinamento do Balanco Energetico Nacional e do Balanco de Energia Util

    Energy Technology Data Exchange (ETDEWEB)

    Leite, Alvaro Afonso Furtado [Universidade Estadual de Santa Cruz (DCET/UESC), Ilheus, BA (Brazil). Dept. de Ciencias Exatas e Tecnologicas], email: aafleite@uesc.br; Bajay, Sergio Valdir [Universidade Estadual de Campinas (NIPE/UNICAMP), SP (Brazil). Fac. de Engenharia Mecanica. Nucleo Interdisciplinar de Planejamento Energetico], email: bajay@fem.unicamp.br

    2010-07-01

    The need to discuss the reformulation of two important tools for the Brazilian energy planning - the National Energy Balance (BEN) and the Useful Energy Balance (BEU) - was the motivation to carry out the study reported in this paper. The concepts embodied in the BEN were set out in the seventies, while those structuring the BEU were defined in the eighties. Since then, the ways to produce, trade and consume energy underwent important changes in Brazil and the expansion planning of the national energy system requires, nowadays, more detailed information and, in some cases, more reliable data than those currently provided by the two balances. They need, thus, to be refined, and this paper aims to contribute towards this goal. (author)

  7. HAMBURG ENERGIE makes biogas plants fit for the balancing energy market; HAMBURG ENERGIE macht Biogasanlagen fit fuer den Regelenergiemarkt

    Energy Technology Data Exchange (ETDEWEB)

    Timmann, Bernd [HAMBURG ENERGIE, Hamburg (Germany). Direktvermarktung und Regelenergie; Bettinger, Carola [HAMBURG ENERGIE, Hamburg (Germany). Forschungsprojekt SMART POWER HAMBURG

    2013-04-15

    HAMBURG ENERGIE GmbH (Hamburg, Federal Republic of Germany) bundles 40 biogas plants with a total capacity of 15 megawatts to a virtual power plant. Thus, also small, decentralized plants may offer negative balancing power and achieve additional profits that were previously available only to large producers. In the medium term, HAMBURG ENERGIE wants to place a performance of 150 MW on the market.

  8. The Global Energy Balance Archive (GEBA) version 2017: a database for worldwide measured surface energy fluxes

    Science.gov (United States)

    Wild, Martin; Ohmura, Atsumu; Schär, Christoph; Müller, Guido; Folini, Doris; Schwarz, Matthias; Zyta Hakuba, Maria; Sanchez-Lorenzo, Arturo

    2017-08-01

    The Global Energy Balance Archive (GEBA) is a database for the central storage of the worldwide measured energy fluxes at the Earth's surface, maintained at ETH Zurich (Switzerland). This paper documents the status of the GEBA version 2017 dataset, presents the new web interface and user access, and reviews the scientific impact that GEBA data had in various applications. GEBA has continuously been expanded and updated and contains in its 2017 version around 500 000 monthly mean entries of various surface energy balance components measured at 2500 locations. The database contains observations from 15 surface energy flux components, with the most widely measured quantity available in GEBA being the shortwave radiation incident at the Earth's surface (global radiation). Many of the historic records extend over several decades. GEBA contains monthly data from a variety of sources, namely from the World Radiation Data Centre (WRDC) in St. Petersburg, from national weather services, from different research networks (BSRN, ARM, SURFRAD), from peer-reviewed publications, project and data reports, and from personal communications. Quality checks are applied to test for gross errors in the dataset. GEBA has played a key role in various research applications, such as in the quantification of the global energy balance, in the discussion of the anomalous atmospheric shortwave absorption, and in the detection of multi-decadal variations in global radiation, known as global dimming and brightening. GEBA is further extensively used for the evaluation of climate models and satellite-derived surface flux products. On a more applied level, GEBA provides the basis for engineering applications in the context of solar power generation, water management, agricultural production and tourism. GEBA is publicly accessible through the internet via http://www.geba.ethz.ch. Supplementary data are available at https://doi.org/10.1594/PANGAEA.873078.

  9. Energy balances for power plants; Energiebilanzen fuer Kraftwerke. Aus Energie wird Elektrizitaet

    Energy Technology Data Exchange (ETDEWEB)

    Baumgartner, W.; Muggli, Ch

    1997-07-01

    An important aspect of a power plant is its energy balance, i.e. the electrical energy produced by the plant over its overall operation period, compared to the amount of non-renewable energy used to create and build the plant. Tense discussions took place in the past between criticizers and promotors of a given technology, some technologies even being accused of having a negative energy balance. Mostly based on built examples the present study aims at giving objective data for the represented technologies, as follows: a 64 MW hydro power plant in the Alps, with seasonal water storage in a lake; a 60 MW run-of-river high-head hydro power plant in the Alps; two run-of-river low-head hydro power plants in the Swiss Midlands (14 MW and 25 MW respectively); a small 30 kW wind power generator located near the Simplon Pass at 2000 m over sea level, in the Alps; a 3 kW photovoltaic generator in the roof of a single-family house; a 500 kW photovoltaic power plant in the Jura, at 1000 m over sea level; a 0.9 MW{sub el}/8.8 MW{sub therm} fossil-fuel co-generation plant near Zuerich; a 200 MW natural-gas-fired gas/vapour turbine power plant; a 300 MW heavy-fuel-fired power plant; a 500 MW coal-fired power plant; and the Leibstadt 990 MW nuclear power plant. The best energy balances are obtained for the hydro power plants, the worst for the Leibstadt nuclear power plant. In between the photovoltaic plants and the fossil-fuel-fired plants are found. The figures differ by more than two orders of magnitude.

  10. Development of net energy ratio and emission factor for quad-generation pathways

    DEFF Research Database (Denmark)

    Rudra, Souman; Rosendahl, Lasse; Kumar, Amit

    2014-01-01

    The conversion of biomass to four different outputs via gasification is a renewable technology that could reduce the use of fossil fuels and greenhouse gas (GHG) emissions. This study investigates the energy aspects for a new concept of biomass based quad-generation plant producing power, heat......, methanol and methane. Circulating fluidized bed gasifier and the gas technology institute (GTI) gasifier technologies are used for this quad-generation process. Two different biomass feedstocks are considered in this study. The net energy ratio for six different pathways having the range of between 1.......3 and 7.2. The lowest limit corresponds to the wood chips-based power, heat, methanol and methane production pathway using GTI technology. Since more efficient alternatives exist for the generation of heat and electricity from biomass, it is argued that syngas is best used for methanol production. The aim...

  11. Environment-physiology, diet quality and energy balance: the influence of early life nutrition on future energy balance.

    Science.gov (United States)

    Burdge, Graham C; Lillycrop, Karen A

    2014-07-01

    Diseases caused by impaired regulation of energy balance, in particular obesity, represent a major global health burden. Although polymorphisms, lifestyle and dietary choices have been associated with differential risk of obesity and related conditions, a substantial proportion of the variation in disease risk remains unexplained. Evidence from epidemiological studies, natural experiments and from studies in animal models has shown that a poor intra-uterine environment is associated causally with increased risk of obesity and metabolic disease in adulthood. Induction of phenotypes that increase disease risk involves the fetus receiving cues from the mother about the environment which, via developmental plasticity, modify the phenotype of the offspring to match her environment. However, inaccurate information may induce an offspring phenotype that is mismatched to the future environment. Such mismatch has been suggested to underlie increased risk of metabolic disease associated with a poor early life environment. Recent studies have shown that induction of modified phenotypes in the offspring involves altered epigenetic regulation of specific genes. Identification of a central role of epigenetics in the aetiology of obesity and metabolic disease may facilitate the development of novel therapeutic interventions and of biomarkers of disease risk. Copyright © 2013 Elsevier Inc. All rights reserved.

  12. Energy requirements, protein-energy metabolism and balance, and carbohydrates in preterm infants.

    Science.gov (United States)

    Hay, William W; Brown, Laura D; Denne, Scott C

    2014-01-01

    Energy is necessary for all vital functions of the body at molecular, cellular, organ, and systemic levels. Preterm infants have minimum energy requirements for basal metabolism and growth, but also have requirements for unique physiology and metabolism that influence energy expenditure. These include body size, postnatal age, physical activity, dietary intake, environmental temperatures, energy losses in the stool and urine, and clinical conditions and diseases, as well as changes in body composition. Both energy and protein are necessary to produce normal rates of growth. Carbohydrates (primarily glucose) are principle sources of energy for the brain and heart until lipid oxidation develops over several days to weeks after birth. A higher protein/energy ratio is necessary in most preterm infants to approximate normal intrauterine growth rates. Lean tissue is predominantly produced during early gestation, which continues through to term. During later gestation, fat accretion in adipose tissue adds increasingly large caloric requirements to the lean tissue growth. Once protein intake is sufficient to promote net lean body accretion, additional energy primarily produces more body fat, which increases almost linearly at energy intakes >80-90 kcal/kg/day in normal, healthy preterm infants. Rapid gains in adiposity have the potential to produce later life obesity, an increasingly recognized risk of excessive energy intake. In addition to fundamental requirements for glucose, protein, and fat, a variety of non-glucose carbohydrates found in human milk may have important roles in promoting growth and development, as well as production of a gut microbiome that could protect against necrotizing enterocolitis. © 2014 S. Karger AG, Basel.

  13. Neutron balance as indicator of long-term resource availability in growing nuclear energy system

    Energy Technology Data Exchange (ETDEWEB)

    Blandinskiy, Victor [National Research Centre ' ' Kurchatov Institute' ' , Moscow (Russian Federation)

    2017-09-15

    The article describes neutron balance in nuclear energy system as necessary but not sufficient indicator of long-term sustainability. Three models are introduced to evaluate neutron balance based on nuclide chain evolution and reaction rates comparison. The indicator introduced is used to compare several nuclear energy systems consisting of thermal, fast and molten salt reactors.

  14. Socioecological correlates of energy balance using urinary C-peptide measurements in wild female mountain gorillas.

    Science.gov (United States)

    Grueter, Cyril C; Deschner, Tobias; Behringer, Verena; Fawcett, Katie; Robbins, Martha M

    2014-03-29

    Maintaining a balanced energy budget is important for survival and reproduction, but measuring energy balance in wild animals has been fraught with difficulties. Female mountain gorillas are interesting subjects to examine environmental correlates of energy balance because their diet is primarily herbaceous vegetation, their food supply shows little seasonal variation and is abundant, yet they live in cooler, high-altitude habitats that may bring about energetic challenges. Social and reproductive parameters may also influence energy balance. Urinary C-peptide (UCP) has emerged as a valuable non-invasive biomarker of energy balance in primates. Here we use this method to investigate factors influencing energy balance in mountain gorillas of the Virunga Volcanoes, Rwanda. We examined a range of socioecological variables on energy balance in adult females in three groups monitored by the Karisoke Research Center over nine months. Three variables had significant effects on UCP levels: habitat (highest levels in the bamboo zone), season (highest levels in November during peak of the bamboo shoot availability) and day time (gradually increasing from early morning to early afternoon). There was no significant effect of reproductive state and dominance rank. Our study indicates that even in species that inhabit an area with a seemingly steady food supply, ecological variability can have pronounced effects on female energy balance. Copyright © 2014 Elsevier Inc. All rights reserved.

  15. Surface energy balance closure in an arid region: role of soil and heat flux

    NARCIS (Netherlands)

    Heusinkveld, B.G.; Jacobs, A.F.G.; Holtslag, A.A.M.; Berkowicz, S.M.

    2004-01-01

    The large soil heat fluxes in hot desert regions are very important in energy balance studies. Surface energy balance (SEB) observations, however, reveal that there is an imbalance in Surface flux measurements and that it is difficult to isolate those flux measurements causing the imbalance errors.

  16. Refined energy-balance modelling of a supraglacial pond, Langtang Khola, Nepal

    NARCIS (Netherlands)

    Miles, Evan S.; Pellicciotti, Francesca; Willis, Ian C.; Steiner, Jakob F.|info:eu-repo/dai/nl/119338653; Buri, Pascal; Arnold, Neil S.

    2016-01-01

    Supraglacial ponds on debris-covered glaciers present a mechanism of atmosphere/glacier energy transfer that is poorly studied, and only conceptually included in mass-balance studies of debris-covered glaciers. This research advances previous efforts to develop a model of mass and energy balance for

  17. Modelling evapotranspiration using the surface energy balance systems (sebs) and landsat tm data (rabat region, morocco)

    NARCIS (Netherlands)

    Kwast, J. van der; Jong, S.M. de

    2004-01-01

    Modelling and understanding the surface energy balance is important for assessing the re-distribution of moisture and heat in soil and atmosphere. The Surface Energy Balance System (SEBS) estimates turbulent heat fluxes using satellite earth observation data in the visible, near infrared, and

  18. Nutrition in ultra-endurance racing - aspects of energy balance, fluid balance and exercise-associated hyponatremia

    OpenAIRE

    Knechtle, B

    2013-01-01

    Ultra-endurance athletes try to extend their limits in performance. In ultra-endurance races, athletes face limits in nutrition regarding both energy intake and fluid metabolism. The purpose of this review is to focus on the decrease in body mass, aspects of energy and fluid balance, and exercise-associated hyponatremia in ultra-endurance performance. An ultra-endurance performance lasting 24 hours or longer may lead to an energy deficit of approximately 7,000 kcal per day. This energy defici...

  19. Relationships between net primary productivity and stand age for several forest types and their influence on China's carbon balance.

    Science.gov (United States)

    Wang, Shaoqiang; Zhou, Lei; Chen, Jingming; Ju, Weimin; Feng, Xianfeng; Wu, Weixing

    2011-06-01

    Affected by natural and anthropogenic disturbances such as forest fires, insect-induced mortality and harvesting, forest stand age plays an important role in determining the distribution of carbon pools and fluxes in a variety of forest ecosystems. An improved understanding of the relationship between net primary productivity (NPP) and stand age (i.e., age-related increase and decline in forest productivity) is essential for the simulation and prediction of the global carbon cycle at annual, decadal, centurial, or even longer temporal scales. In this paper, we developed functions describing the relationship between national mean NPP and stand age using stand age information derived from forest inventory data and NPP simulated by the BEPS (Boreal Ecosystem Productivity Simulator) model in 2001. Due to differences in ecobiophysical characteristics of different forest types, NPP-age equations were developed for five typical forest ecosystems in China (deciduous needleleaf forest (DNF), evergreen needleleaf forest in tropic and subtropical zones (ENF-S), deciduous broadleaf forest (DBF), evergreen broadleaf forest (EBF), and mixed broadleaf forest (MBF)). For DNF, ENF-S, EBF, and MBF, changes in NPP with age were well fitted with a common non-linear function, with R(2) values equal to 0.90, 0.75, 0.66, and 0.67, respectively. In contrast, a second order polynomial was best suitable for simulating the change of NPP for DBF, with an R(2) value of 0.79. The timing and magnitude of the maximum NPP varied with forest types. DNF, EBF, and MBF reached the peak NPP at the age of 54, 40, and 32 years, respectively, while the NPP of ENF-S maximizes at the age of 13 years. The highest NPP of DBF appeared at 122 years. NPP was generally lower in older stands with the exception of DBF, and this particular finding runs counter to the paradigm of age-related decline in forest growth. Evaluation based on measurements of NPP and stand age at the plot-level demonstrates the reliability

  20. Bayesian analysis of energy balance data from growing cattle using parametric and non-parametric modelling

    NARCIS (Netherlands)

    Moraes, L.E.; Kebreab, E.; Strathe, A.B.; France, J.; Dijkstra, J.; Casper, D.; Fadel, J.G.

    2014-01-01

    Linear and non-linear models have been extensively utilised for the estimation of net and metabolisable energy requirements and for the estimation of the efficiencies of utilising dietary energy for maintenance and tissue gain. In growing animals, biological principles imply that energy retention

  1. The National Energy Strategy: A balanced program?. Proceedings of the nineteenth annual Illinois energy conference

    Energy Technology Data Exchange (ETDEWEB)

    1991-12-31

    The Nineteenth Annual Illinois Energy Conference was held in Chicago, Illinois November 1991. It was organized by the Energy Resources Center, University of Illinois at Chicago with major support provided by the US Environmental Protection Agency, the US Department of Energy, the Illinois Commerce Commission, the Illinois Department of Energy and Natural Resources, and the Citizens Council on Energy Resources. The conference program was developed by a planning committee who drew upon Illinois energy and environmental specialists from the major sectors including energy industries, environmental organizations, research universities, utility companies, federal, state and local government agencies, and public interest groups. The members of the planning committee were brought together for a full-day session where they were asked to assess the political, economic, and social impacts of the proposed National Energy Strategy as it relates to Illinois and the Midwest region. Within this context, the planning committee identified several major issues including: (1) Is the proposed plan a balanced strategy; (2) What are the NES impacts on the transportation sector; (3) What are the opportunities for improved efficiency in the Electric Utility Sector; and (4) What is the role of advanced research and development.

  2. Anaerobic digestion of ultrasonicated sludge at different solids concentrations - Computation of mass-energy balance and greenhouse gas emissions.

    Science.gov (United States)

    Pilli, Sridhar; Yan, S; Tyagi, R D; Surampalli, R Y

    2016-01-15

    Two cases of anaerobic digestion (AD) of sludge, namely (i) with pre-treatment and (ii) without pre-treatment, were assessed using mass-energy balance and the corresponding greenhouse gas (GHG) emissions. For a digestion period of 30 days, volatile solids degradation of the control sludge and the ultrasonicated secondary sludge was 51.4% and 60.1%, respectively. Mass balance revealed that the quantity of digestate required for dewatering, transport and land application was the lowest (20.2 × 10(6) g dry sludge/day) for ultrasonicated secondary sludge at 31.4 g TS/L. Furthermore, for ultrasonicated secondary sludge at 31.4 g TS/L, the maximum net energy (energy output - energy input) of total dry solids (TDS) was 7.89 × 10(-6) kWh/g and the energy ratio (output/input) was 1.0. GHG emissions were also reduced with an increase in the sludge solids concentration (i.e., 40.0 g TS/L < 30.0 g TS/L < 20.0 g TS/L). Ultrasonication pre-treatment proved to be efficient and beneficial for enhancing anaerobic digestion efficiency of the secondary sludge when compared to the primary and mixed sludge. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. Energy and mass balance observations on La Mare Glacier (Ortles-Cevedale, European Alps)

    Science.gov (United States)

    Carturan, L.; Cazorzi, F.; Dalla Fontana, G.

    2009-04-01

    An experimental site was setup in 2005 on the ablation area of La Mare Glacier, at 2990 m a.s.l., to study the energy and mass balance exchanges between the glacier surface and the atmosphere and to investigate the climatic sensitivity of this particular glacier. An Automatic Weather Station was operated, in the framework of a monitoring network which has been implemented in the Upper Val de La Mare experimental watershed (Trentino, Italy). This basin was selected for a study of climate change effects on cryosphere and hydrology at high-altitude catchments. The 36.2 km2 wide basin has an average altitude of 2906 m a.s.l. and at present the 25% of its surface is glacierized; the annual runoff regime is dominated by snow and ice melt. Direct mass balance measurements have been performed since 1967 on Careser glacier (2.83 km2) and since 2003 on La Mare glacier (3.97 km2). The AWS is mounted on a tripod which stands freely on the glacier surface and is solar-powered. The variables measured are: air temperature and relative humidity, wind speed and direction, shortwave and longwave incoming and outgoing radiation, precipitation and surface height. All the data are sampled at five-minute intervals as average values, with the exception of surface height which is sampled at hourly intervals, as instantaneous values. The collected data were used to calculate the point energy and mass balance and to compare the results with similar investigations carried out on glaciers and available in literature. In particular, our attention has been focussed on some processes which regulate the response to climate changes. The relative importance of the energy balance components was examined and a clear predominance of shortwave radiation inputs was found to exist during melt conditions. Given the relevance of the shortwave net balance, the ice albedo temporal variability (values ranging from 0.1 to 0.5) has been investigated and correlated with meteorological variables. Furthermore, a

  4. Energy Use Intensity and its Influence on the Integrated Daylighting Design of a Large Net Zero Energy Building: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Guglielmetti , R.; Scheib, J.; Pless, S. D.; Torcellini , P.; Petro, R.

    2011-03-01

    Net-zero energy buildings generate as much energy as they consume and are significant in the sustainable future of building design and construction. The role of daylighting (and its simulation) in the design process becomes critical. In this paper we present the process the National Renewable Energy Laboratory embarked on in the procurement, design, and construction of its newest building, the Research Support Facility (RSF) - particularly the roles of daylighting, electric lighting, and simulation. With a rapid construction schedule, the procurement, design, and construction had to be tightly integrated; with low energy use. We outline the process and measures required to manage a building design that could expect to operate at an efficiency previously unheard of for a building of this type, size, and density. Rigorous simulation of the daylighting and the electric lighting control response was a given, but the oft-ignored disconnect between lighting simulation and whole-building energy use simulation had to be addressed. The RSF project will be thoroughly evaluated for its performance for one year; preliminary data from the postoccupancy monitoring efforts will also be presented with an eye toward the current efficacy of building energy and lighting simulation.

  5. Understanding the Relationship Between Food Variety, Food Intake, and Energy Balance.

    Science.gov (United States)

    Raynor, Hollie A; Vadiveloo, Maya

    2018-03-01

    In accordance with US dietary guidance, incorporating variety into the diet can align with energy balance, though greater food variety in some categories may make energy balance more challenging. Thus, experimental and epidemiologic evidence is summarized on the relationship between food variety, food and energy intake, and energy balance. Lab-based, experimental research consistently demonstrates that greater variety within foods or sensory characteristics of food increases food and energy intake within an eating occasion. Epidemiologic evidence is less consistent, potentially driven by differing methodologies, particularly in defining and measuring food variety. Moreover, the effect of variety on energy balance appears to be moderated by food energy density. Integrating insights from experimental and epidemiologic research are essential for strengthening food variety guidance including developing evidence-based definitions of food variety, understanding moderators of the relationship, and developing practical guidance interpretable to consumers.

  6. Trends in research on energy balance supported by the National Cancer Institute.

    Science.gov (United States)

    Ballard-Barbash, Rachel; Siddiqi, Sameer M; Berrigan, David A; Ross, Sharon A; Nebeling, Linda C; Dowling, Emily C

    2013-04-01

    Over the past decade, the body of research linking energy balance to the incidence, development, progression, and treatment of cancer has grown substantially. No prior NIH portfolio analyses have focused on energy balance within one institute. This portfolio analysis describes the growth of National Cancer Institute (NCI) grant research on energy balance-related conditions and behaviors from 2004 to 2010 following the release of an NCI research priority statement in 2003 on energy balance and cancer-related research. Energy balance grants from fiscal years (FY) 2004 to 2010 were identified using multiple search terms and analyzed between calendar years 2008 and 2010. Study characteristics related to cancer site, design, population, and energy balance area (physical activity, diet, and weight) were abstracted. From FY2004 to FY2010, the NCI awarded 269 energy balance-relevant grants totaling $518 million. In FY2010, 4.2% of NCI's total research project grants budget was allocated to energy balance research, compared to 2.1% in FY2004. The NCI more than doubled support for investigator-initiated research project grants (R01) and increased support for cooperative agreement (U01, U54) and exploratory research (R21) grants. In the portfolio, research examining energy balance areas in combination accounted for 41.6%, and observational and interventional studies were equally represented (38.3% and 37.2%, respectively). Breast cancer was the most commonly studied cancer. Inclusion of minorities rose, and funding specific to cancer survivors more than doubled. From FY2004 to FY2010, NCI's investment in energy balance and related health behavior research showed growth in funding and diversity of mechanisms, topics, and disciplines-growth that reflects new directions in this field. Published by Elsevier Inc.

  7. Radiation and energy balance dynamics over young chir pine ...

    Indian Academy of Sciences (India)

    Net short wave and long wave radiative fluxes substantially varied with cloud dynamics, season, rainfall induced surface wetness, and green growth. The study clearly brought out the intimate link of albedo dynamics in chir pine system with dynamics of leaf area index (LAI), soil moisture, and changes in understory ...

  8. Net energy payback and CO2 emissions from three midwestern wind farms: An update

    Science.gov (United States)

    White, S.W.

    2006-01-01

    This paper updates a life-cycle net energy analysis and carbon dioxide emissions analysis of three Midwestern utility-scale wind systems. Both the Energy Payback Ratio (EPR) and CO2 analysis results provide useful data for policy discussions regarding an efficient and low-carbon energy mix. The EPR is the amount of electrical energy produced for the lifetime of the power plant divided by the total amount of energy required to procure and transport the materials, build, operate, and decommission the power plants. The CO2 analysis for each power plant was calculated from the life-cycle energy input data. A previous study also analyzed coal and nuclear fission power plants. At the time of that study, two of the three wind systems had less than a full year of generation data to project the life-cycle energy production. This study updates the analysis of three wind systems with an additional four to eight years of operating data. The EPR for the utility-scale wind systems ranges from a low of 11 for a two-turbine system in Wisconsin to 28 for a 143-turbine system in southwestern Minnesota. The EPR is 11 for coal, 25 for fission with gas centrifuge enriched uranium and 7 for gaseous diffusion enriched uranium. The normalized CO2 emissions, in tonnes of CO2 per GW eh, ranges from 14 to 33 for the wind systems, 974 for coal, and 10 and 34 for nuclear fission using gas centrifuge and gaseous diffusion enriched uranium, respectively. ?? Springer Science+Business Media, LLC 2007.

  9. A mobile system for quantifying the spatial variability of the surface energy balance: design and application

    Science.gov (United States)

    Wohlfahrt, Georg; Tasser, Erich

    2015-05-01

    We present a mobile device for the quantification of the small-scale (a few square meters) spatial variability in the surface energy balance components and several auxiliary variables of short-statured (wind speed, soil temperature and soil water content. Data are acquired by a battery-powered data logger, which is mounted on a backpack together with the auxiliary sensors. The proposed device was developed to bridge between the spatial scales of satellite/airborne remote sensing and fixed, stationary tower-based measurements with an emphasis on micrometeorological, catchment hydrological and landscape-ecological research questions. The potential of the new device is demonstrated through four selected case studies, which cover the issues of net radiation heterogeneity within the footprint of eddy covariance flux measurements due to (1) land use and (2) slope and aspect of the underlying surface, (3) controls on landscape-scale variability in soil temperature and albedo and (4) the estimation of evapotranspiration based exclusively on measurements with the mobile device.

  10. Balancing

    Science.gov (United States)

    Harteveld, Casper

    At many occasions we are asked to achieve a “balance” in our lives: when it comes, for example, to work and food. Balancing is crucial in game design as well as many have pointed out. In games with a meaningful purpose, however, balancing is remarkably different. It involves the balancing of three different worlds, the worlds of Reality, Meaning, and Play. From the experience of designing Levee Patroller, I observed that different types of tensions can come into existence that require balancing. It is possible to conceive of within-worlds dilemmas, between-worlds dilemmas, and trilemmas. The first, the within-world dilemmas, only take place within one of the worlds. We can think, for example, of a user interface problem which just relates to the world of Play. The second, the between-worlds dilemmas, have to do with a tension in which two worlds are predominantly involved. Choosing between a cartoon or a realistic style concerns, for instance, a tension between Reality and Play. Finally, the trilemmas are those in which all three worlds play an important role. For each of the types of tensions, I will give in this level a concrete example from the development of Levee Patroller. Although these examples come from just one game, I think the examples can be exemplary for other game development projects as they may represent stereotypical tensions. Therefore, to achieve harmony in any of these forthcoming games, it is worthwhile to study the struggles we had to deal with.

  11. Nearly Net-Zero Exergy Districts as Models for Smart Energy Systems

    Directory of Open Access Journals (Sweden)

    Şiir Kilkiş

    2017-03-01

    Full Text Available The planning of urban settlements requires a targeted approach towards more sustainable energy, water, and environment systems. This research work analyses the city of Uppsala and a district that is an urban renewal project at the site of former high voltage power lines, namely Östra Sala backe, which will have a new energy concept. The latter is analysed based on proposals for two phases that aim to reach a net-zero district target based on the quality of energy (exergy. An indicator set with five main categories is introduced based on per capita values to enable a comparable basis between the scales of the city and the district, including exergy per capita as a new indicator. The present status of Uppsala is further analysed based on Sankey diagrams to provide insight into the present urban metabolism of the city. The results indicate that the best practice values of Östra Sala backe based on phase two can achieve significant savings in per capita values, which include 5.5 MWh of energy usage, 6.1 MWh of exergy consumption, 33 m3 of water consumption, 22 kg of waste generation, and 4.2 tonnes of carbon dioxide (CO2 emissions. Additional scenarios for Uppsala indicate that the district can be about 10 years ahead of the city’s existing performance.

  12. Chapter 21: Estimating Net Savings - Common Practices. The Uniform Methods Project: Methods for Determining Energy Efficiency Savings for Specific Measures

    Energy Technology Data Exchange (ETDEWEB)

    Kurnik, Charles W [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Violette, Daniel M. [Navigant, Boulder, CO (United States); Rathbun, Pamela [Tetra Tech, Madison, WI (United States)

    2017-11-02

    This chapter focuses on the methods used to estimate net energy savings in evaluation, measurement, and verification (EM and V) studies for energy efficiency (EE) programs. The chapter provides a definition of net savings, which remains an unsettled topic both within the EE evaluation community and across the broader public policy evaluation community, particularly in the context of attribution of savings to a program. The chapter differs from the measure-specific Uniform Methods Project (UMP) chapters in both its approach and work product. Unlike other UMP resources that provide recommended protocols for determining gross energy savings, this chapter describes and compares the current industry practices for determining net energy savings but does not prescribe methods.

  13. Analysis of meteorological data and the surface energy balance of Keqicar Glacier, Tien Shan, China

    Science.gov (United States)

    Zhang, Y.; Liu, S.; Fujita, K.; Han, H.; Li, J.

    2009-04-01

    weather station on the glacier measured an average temperature of 2.6 °C (at 2m height above surface). The lapse rate of air temperature is close to the standard free atmospheric lapse rate (0.6 °C per 100m), which shows the cold effect of glacier is not significant. The local mountain-valley winds is significant, the speed of which is 2.3 m s-1 (at 2m height). Glacier is dominated by the convectional precipitation, 75% of which occurs in day time. The ablation stakes indicate a specific mass balance of -2.5 m w.e. between 1 July and 13 September. The specific mass balance calculated from the surface energy balance, -2.6 m w.e., is in close correspondence to this. The thermal processes on the debris layer are quite different from those on bare ice or snow. The main physical characteristics of the debris layer are the thermal conductivity and albedo that control heat conduction to the ice-debris interface. Net radiation is the main melt energy whether the debris layer is taken into consideration or not, which is lager between July and the middle of August, and then decreases. This is coincides with the glacier ablation. On the debris-covered area, the sensible- and latent-heat fluxes contribute 19.6% of the melt energy, higher than that on the debris-free ice (4.1%). Hence, due to the existing debris layer, the ablation shows a significant spatial distribution.

  14. Urinary C-peptide is not an accurate bioindicator of energy balance in humans.

    Science.gov (United States)

    Bergouignan, Audrey; Habold, Caroline; Rudwill, Floriane; Gauquelin-Koch, Guillemette; Normand, Sylvie; Simon, Chantal; Blanc, Stéphane

    2012-03-01

    The apprehension of the factors that affect long term regulation of energy balance is indispensable to understand the rise in obesity prevalence as well as to delineate levers to prevent it. Accurate measurements of energy balance are however challenging during free-living conditions. Recent studies proposed urinary C-peptide, a metabolic byproduct of insulin synthesis, as reliable noninvasive assessment of energy balance. These studies were in fact essentially based on correlations between urinary C-peptide and energy intake and only focused on nonhuman primates. During a bed-rest study conducted in 16 healthy women in a controlled environment, we tested the existence of a relationship between 24 h-urinary C-peptide and energy balance in humans. Daily energy intake and body mass, body composition (dual-energy X-ray absorptiometry (DXA)) and total energy expenditure (doubly labeled water (DLW) method) was measured and energy balance was calculated as the difference between energy intake and expenditure. Urinary C-peptide was positively correlated with bed-rest-induced changes in fat mass (r(2) = 0.285; P = 0.03) and energy balance assessed at the end of the bed-rest (r(2) = 0.302; P = 0.027). However, in this tightly controlled environment, urinary C-peptide only accounted for 30% of variations in energy balance. No relationship was noted between urinary C-peptide and body or fat mass both at baseline and at the end of the bed-rest. These results indicate that urinary C-peptide cannot be used as an accurate biomarker of energy balance in the general human population in free-living conditions.

  15. An Enhanced Energy Balanced Data Transmission Protocol for Underwater Acoustic Sensor Networks.

    Science.gov (United States)

    Javaid, Nadeem; Shah, Mehreen; Ahmad, Ashfaq; Imran, Muhammad; Khan, Majid Iqbal; Vasilakos, Athanasios V

    2016-04-07

    This paper presents two new energy balanced routing protocols for Underwater Acoustic Sensor Networks (UASNs); Efficient and Balanced Energy consumption Technique (EBET) and Enhanced EBET (EEBET). The first proposed protocol avoids direct transmission over long distance to save sufficient amount of energy consumed in the routing process. The second protocol overcomes the deficiencies in both Balanced Transmission Mechanism (BTM) and EBET techniques. EBET selects relay node on the basis of optimal distance threshold which leads to network lifetime prolongation. The initial energy of each sensor node is divided into energy levels for balanced energy consumption. Selection of high energy level node within transmission range avoids long distance direct data transmission. The EEBET incorporates depth threshold to minimize the number of hops between source node and sink while eradicating backward data transmissions. The EBET technique balances energy consumption within successive ring sectors, while, EEBET balances energy consumption of the entire network. In EEBET, optimum number of energy levels are also calculated to further enhance the network lifetime. Effectiveness of the proposed schemes is validated through simulations where these are compared with two existing routing protocols in terms of network lifetime, transmission loss, and throughput. The simulations are conducted under different network radii and varied number of nodes.

  16. Higher moments of net kaon multiplicity distributions at RHIC energies for the search of QCD Critical Point at STAR

    Directory of Open Access Journals (Sweden)

    Sarkar Amal

    2013-11-01

    Full Text Available In this paper we report the measurements of the various moments mean (M, standard deviation (σ skewness (S and kurtosis (κ of the net-Kaon multiplicity distribution at midrapidity from Au+Au collisions at √sNN = 7.7 to 200 GeV in the STAR experiment at RHIC in an effort to locate the critical point in the QCD phase diagram. These moments and their products are related to the thermodynamic susceptibilities of conserved quantities such as net baryon number, net charge, and net strangeness as also to the correlation length of the system. A non-monotonic behavior of these variable indicate the presence of the critical point. In this work we also present the moments products Sσ, κσ2 of net-Kaon multiplicity distribution as a function of collision centrality and energies. The energy and the centrality dependence of higher moments of net-Kaons and their products have been compared with it0s Poisson expectation and with simulations from AMPT which does not include the critical point. From the measurement at all seven available beam energies, we find no evidence for a critical point in the QCD phase diagram for √sNN below 200 GeV.

  17. ASAS centennial paper: net energy systems for beef cattle--concepts, application, and future models.

    Science.gov (United States)

    Ferrell, C L; Oltjen, J W

    2008-10-01

    Development of nutritional energetics can be traced to the 1400s. Lavoisier established relationships among O(2) use, CO(2) production and heat production in the late 1700s, and the laws of thermodynamics and law of Hess were discovered during the 1840s. Those discoveries established the fundamental bases for nutritional energetics and enabled the fundamental entity ME = retained energy + heat energy to be established. Objectives became: 1) to establish relationships between gas exchange and heat energy, 2) to devise bases for evaluation of foods that could be related to energy expenditures, and 3) to establish causes of energy expenditures. From these endeavors, the basic concepts of energy partitioning by animals were developed, ultimately resulting in the development of feeding systems based on NE concepts. The California Net Energy System, developed for finishing beef cattle, was the first to be based on retained energy as determined by comparative slaughter and the first to use 2 NE values (NE(m) and NE(g)) to describe feed and animal requirements. The system has been broadened conceptually to encompass life cycle energy requirements of beef cattle and modified by the inclusion of numerous adjustments to address factors known to affect energy requirements and value of feed to meet those needs. The current NE system remains useful but is empirical and static in nature and thus fails to capture the dynamics of energy utilization by diverse animals as they respond to changing environmental conditions. Consequently, efforts were initiated to develop dynamic simulation models that captured the underlying biology and thus were sensitive to variable genetic and environmental conditions. Development of a series of models has been described to show examples of the conceptual evolution of dynamic, mechanistic models and their applications. Generally with each new system, advances in prediction accuracy came about by adding new terms to conceptually validated models

  18. Design of advanced solar homes aimed at net-zero annual energy consumption in Canada

    Energy Technology Data Exchange (ETDEWEB)

    Athienitis, Andreas

    2010-09-15

    This paper overviews the design of three sustainable low or net-zero energy solar homes in Canada. The major features of the houses are: 1. direct gain passive solar design that emphasizes utilization of distributed thermal mass in the equatorial-facing part of the ground floor; 2. a building-integrated photovoltaic-thermal system (BIPV/T); 3. a two-stage ground-source heat pump used to heat/cool air in the house or an air source heat pump using BIPV/T air as the source to heat a storage tank; 4. a floor heating system integrated in the floor mass of the direct gain zone; 5. a multizone programmable thermostat.

  19. Re(De)fining Net Zero Energy: Renewable Emergy Balance in Environmental Building Design

    Science.gov (United States)

    The notion that raw materials for building construction are plentiful and can be extracted “at will” from Earth’s geobiosphere, and that these materials do not undergo any degradation or related deterioration in performance while in use is alarming and entirely inaccurate. For th...

  20. Complete energy balance relation in relativistic magnetic reconnection and its application for guide-field reconnection

    Science.gov (United States)

    Yang, Shu-Di

    2017-01-01

    Energy balance equation for steady state Sweet-Parker reconnection in a relativistic regime is reanalyzed, employing a complete electromagnetic energy equation. A correction related to Vin is added with electric energy taken into account. The validity and meaning of the correction are demonstrated with the energy-momentum tensor. Predictions of the new scaling are compared with the previous ones. Energy calculation is also used in the cases with guide field, with a view to the role of the guide field for energy balance. And the relativistic tearing mode growth rate with guide field is discussed using the fluid model.

  1. Photonic microstructures for energy-generating clear glass and net-zero energy buildings

    Science.gov (United States)

    Vasiliev, Mikhail; Alghamedi, Ramzy; Nur-E-Alam, Mohammad; Alameh, Kamal

    2016-08-01

    Transparent energy-harvesting windows are emerging as practical building-integrated photovoltaics (BIPV), capable of generating electricity while simultaneously reducing heating and cooling demands. By incorporating spectrally-selective diffraction gratings as light deflecting structures of high visible transparency into lamination interlayers and using improved spectrally-selective thin-film coatings, most of the visible solar radiation can be transmitted through the glass windows with minimum attenuation. At the same time, the ultraviolet (UV) and a part of incident solar infrared (IR) radiation energy are converted and/or deflected geometrically towards the panel edge for collection by CuInSe2 solar cells. Experimental results show power conversion efficiencies in excess of 3.04% in 10 cm × 10 cm vertically-placed clear glass panels facing direct sunlight, and up to 2.08% in 50 cm × 50 cm installation-ready framed window systems. These results confirm the emergence of a new class of solar window system ready for industrial application.

  2. Solar array design based on shadow analysis for increasing net energy collection in a competition vehicle

    Science.gov (United States)

    Osorio-Gómez, Gilberto; Mejía-Gutiérrez, Ricardo; Suárez-Castañeda, Nicolás; Gil-Herrera, Ana; Barrera-Velásquez, Jorge

    2015-01-01

    Photovoltaic (PV) applications such as in the architectural, automotive, and aerospace industries face design contradictions because they are expected to produce a lot of energy but are constrained by available area, surface shape, incident irradiance, shadows, and other aspects that have a negative influence on the energy produced by the solar panel. Solar competition vehicles are some of these challenging PV applications. The design of such solar arrays needs to consider efficiency evaluation in order to optimize space; it is difficult not to install solar modules in areas impacted by shadows. A design procedure for a solar array configuration based on shadow analysis for competition vehicles is presented. The principle is that shadows in moving objects can be simulated, since the vehicle, the earth and the sun are are moving in semipredictable patterns, thus net energy collection can be forecast. The case study presented is the solar array design of a vehicle that participated in the World Solar Challenge 2013. The obtained results illustrate how the employment of the procedure gives insights on important aspects to consider and also delivers qualitative and quantitative information for decision making. In addition, the experience in competition highlights some issues to be considered, modified, or improved in further vehicle designs.

  3. Energy balance with Landsat images in irrigated central pivots with corn crop in the São Paulo State, Brazil

    Science.gov (United States)

    Teixeira, Antônio H. d. C.; Hernandez, Fernando B. T.; Andrade, Ricardo G.; Leivas, Janice F.; Bolfe, Edson L.

    2014-10-01

    The energy balance (EB) components were quantified in a commercial farm with corn crop, irrigated by central pivots, in the Northwestern side of São Paulo state, Southeast Brazil. The SAFER (Simple Algorithm For Evapotranspiration Retrieving) was applied to retrieve the latent heat flux (λE), considering six pivots, covering irrigated areas from 74 to 108 ha. With λE quantified and considering soil heat flux (G) as a fraction of net radiation (Rn), the sensible heat flux (H) was acquired as a residual in the energy balance equation. Seven Landsat satellite images, covering all corn crop stages from 23 April 2010 to 29 August 2010, allowed relating the energy balance components according to the accumulated degree-days (DDac) from the planting to harvest dates. The average Rn values ranging from 5.2 to 7.2 MJ m-2 day-1, represented 30 to 45% of global solar radiation (RG). Considering the variation of the energy balance components along the corn crop growing seasons, the average ranges for λE, H and G were respectively 0.0 to 6.4 MJ m-2 day-1, -1.5 to 6.7 MJ m-2 day-1 and 0.1 to 0.6 MJ m-2 day-1. The fraction of the available energy (Rn - G) used as λE was from 0.0 to 1.3 indicated a good irrigation management, insuring that the water deficit could not be the reason of any yield reduction. Although Rn did not reflected well the crop stages, its partition strongly depended on these stages. λE higher than Rn and the negative H/Rn, happening sometimes along the corn growing seasons, occurred after the vegetative growth and before the harvest times, indicated heat advection from the surrounding areas to the irrigation pivots, which represented an additional energy source for the evaporative process. The models applied here with only the visible and infrared bands of the Landsat sensor are very useful for the energy balance analyses, considering the size of the corn crop irrigation pivots in Southeast Brazil, when subsidizing a rational irrigation water application

  4. Effect of drink carbohydrate content on postexercise gastric emptying, rehydration, and the calculation of net fluid balance.

    Science.gov (United States)

    Clayton, David J; Evans, Gethin H; James, Lewis J

    2014-02-01

    The purpose of this study was to examine the gastric emptying and rehydration effects of hypotonic and hypertonic glucose-electrolyte drinks after exercise-induced dehydration. Eight healthy males lost ~1.8% body mass by intermittent cycling and rehydrated (150% of body mass loss) with a hypotonic 2% (2% trial) or a hypertonic 10% (10% trial) glucose-electrolyte drink over 60 min. Blood and urine samples were taken at preexercise, postexercise, and 60, 120, 180, and 240 min postexercise. Gastric and test drink volume were determined 15, 30, 45, 60, 90, and 120 min postexercise. At the end of the gastric sampling period 0.3% (2% trial) and 42.1% (10% trial; p fluid balance was greater from 120 min during the 10% trial (p fluid balance was corrected for the volume of fluid in the stomach, it was greater at 60 and 120 min during the 2% trial (p fluid balance.

  5. Effect of dietary energy source on energy balance, production, metabolic disorders and reproduction in lactating dairy cattle

    NARCIS (Netherlands)

    Knegsel, van A.T.M.; Brand, van den H.; Dijkstra, J.; Tamminga, S.; Kemp, B.

    2005-01-01

    The pathway for oxidation of energy involves a balanced oxidation of C2 and C3 compounds. During early lactation in dairy cattle this C2/C3 ratio is out of balance, due to a high availability of lipogenic (C2) products and a low availability of glycogenic (C3) products relative of the C2 and C3

  6. Analysis of hohlraum energetics of the SG series and the NIF experiments with energy balance model

    Directory of Open Access Journals (Sweden)

    Guoli Ren

    2017-01-01

    Full Text Available The basic energy balance model is applied to analyze the hohlraum energetics data from the Shenguang (SG series laser facilities and the National Ignition Facility (NIF experiments published in the past few years. The analysis shows that the overall hohlraum energetics data are in agreement with the energy balance model within 20% deviation. The 20% deviation might be caused by the diversity in hohlraum parameters, such as material, laser pulse, gas filling density, etc. In addition, the NIF's ignition target designs and our ignition target designs given by simulations are also in accordance with the energy balance model. This work confirms the value of the energy balance model for ignition target design and experimental data assessment, and demonstrates that the NIF energy is enough to achieve ignition if a 1D spherical radiation drive could be created, meanwhile both the laser plasma instabilities and hydrodynamic instabilities could be suppressed.

  7. The Sleep/Wake Cycle is Directly Modulated by Changes in Energy Balance.

    OpenAIRE

    Collet Tinh-Hai; van, der Klaauw Agatha A; Henning Elana; Keogh Julia M.; Suddaby Diane; Dachi Sekesai V; Dunbar Síle; Kelway Sarah; Dickson Suzanne L; Farooqi I. Sadaf; Schmid Sebastian M

    2016-01-01

    STUDY OBJECTIVES:The rise in obesity has been paralleled by a decline in sleep duration in epidemiological studies. However the potential mechanisms linking energy balance and the sleep/wake cycle are not well understood. We aimed to examine the effects of manipulating energy balance on the sleep/wake cycle. METHODS:Twelve healthy normal weight men were housed in a clinical research facility and studied at three time points: baseline after energy balance was disrupted by 2 days of caloric re...

  8. Analysis of energy and greenhouse gas balance as indexes for environmental assessment of wheat and maize farming: a case study

    Directory of Open Access Journals (Sweden)

    Móslem SAMI

    2015-12-01

    Full Text Available In this study, the net balance of greenhouse gas (GHG emission and energy of wheat and maize production systems in two farms in Khuzestan province of Iran was assessed. The results showed that totally wheat farming is more efficient than maize farming in terms of energy and CO2-eq indexes. The total energy requirement for maize and wheat farming was 92560.24 MJ ha-1 and 39624.15 MJ ha-1, which caused the emission of 20191.47 and 7541.04 kg CO2-equivalent per hectare in maize and wheat farms respectively. Electricity, fertilizers and fuel were the most important pollutants of environment in terms of energy and gas emission in both farms. Theses inputs consumed 55.52, 22.62 and 6.44 % of total energy of maize and 47.32, 21.19 and 9.01 % of total energy of wheat farm and were responsible for the 88.60, 8.79 and 2.03 % of CO2-equivalent in maize and 86.54, 9.54 and 3.24 % of CO2-equivalent in wheat farms respectively. The results of this study also showed that the enhancement of 60.74 and 27.02 % in energy ratio and 46.06 and 27.87 % in CO2-eq index in maize and wheat farming can be expected using simple improving scenarios.

  9. Energy indicators for electricity production : comparing technologies and the nature of the indicators Energy Payback Ratio (EPR), Net Energy Ratio (NER) and Cumulative Energy Demand (CED). [Oestfoldforskning AS

    Energy Technology Data Exchange (ETDEWEB)

    Raadal, Hanne Lerche [Ostfold research, Fredrikstad (Norway); Modahl, Ingunn Saur [Ostfold research, Fredrikstad (Norway); Bakken, Tor Haakon [SINTEF Energy, Trondheim (Norway)

    2012-11-01

    CEDREN (Centre for Environmental Design of Renewable Energy) is founded by The Research Council of Norway and energy companies and is one of eight centres that were part of the scheme Centre for Environment-friendly Energy Research (FME) when the scheme was launched in 2009. The main objective of CEDREN is to develop and communicate design solutions for transforming renewable energy sources to the desired energy products, and at the same time address the environmental and societal challenges at local, regional, national and global levels. CEDREN's board initiated in 2011 a pilot project on the topics 'Energy Pay-back Ratio (EPR)', 'Ecosystem services' and 'multi-criteria analysis (MCA)' in order to investigate the possible use of these concepts/indices in the management of regulated river basins and as tools to benchmark strategies for the development of energy projects/resources. The energy indicator part (documented in this report) has aimed at reviewing the applicability of different energy efficiency indicators, as such, in the strategic management and development of energy resources, and to compare and benchmark technologies for production of electricity. The main findings from this pilot study is also reported in a policy memo (in Norwegian), that is available at www.cedren.no. The work carried out in this project will be continued in the succeeding research project EcoManage, which was granted by the Research Council of Norway's RENERGI programme in December 2011. Energy indicators: Several energy indicators for extraction and delivery of an energy product (e.g. transport fuel, heat, electricity etc.) exist today. The main objective of such indicators is to give information about the energy efficiency of the needed extraction and transforming processes throughout the value chain related to the delivered energy product. In this project the indicators Energy Payback Ratio (EPR), Net Energy Ration (NER) and Cumulative

  10. Energy balance and evaporation of a short-rotation willow forest. Variation with season and stand development

    Energy Technology Data Exchange (ETDEWEB)

    Iritz, Z.

    1996-10-01

    Energy balance and evaporation of a short-rotation willow (Salix viminalis L.) forest was studied in relation to season and stand development. The developmental stage of the forest stand considerably influenced how the energy, received as net radiation, was partitioned between the connective fluxes and the storage components. The main part of the available energy was utilised for evaporation during most of the season. Only at the beginning of the season did the willow forest supply heat to the atmosphere. Later in the season, energy was taken from air and utilised for evaporation, which resulted in negative sensible heat fluxes. Soil heat storage was also a significant term in the energy balance and also strongly depended on canopy development. Changes in energy partitioning relative to leaf area indices indicated the existence of a threshold value for leaf area index of the developing canopy. The analysis suggested that the canopy of the willow forest could be considered as closed at a leaf area index of 2. It was further found that evaporation from well-irrigated willow forest occurred also during night-time, particularly in windy and dry weather conditions. The sources of nocturnal evaporation were both the canopy, i.e. indicating non-closed stomata, and the soil surface. Partitioning of the total evaporation into components was investigated using a physically-based model with a two-layer aboveground representation and a two-layer soil module. The model estimates evaporation with respect to developmental stage of the willow stand and also takes into account the interaction between the fluxes from the canopy and the soil surface. Good performance of the model indicated that, after further testing in drier conditions, it could be used as a tool for analysing the prerequisites for energy-forest establishment, and practical management of energy forest stands. 37 refs, 9 figs

  11. Renewable and non-renewable energy consumption and economic growth: Evidence from MENA Net Oil Importing Countries

    OpenAIRE

    Kahia, Montassar; Ben Aissa, Mohamed Safouane

    2014-01-01

    In this paper, we use panel cointegration techniques to explore the relationship between renewable and non-renewable energy consumption and economic growth in a sample of 11 MENA Net Oil Importing Countries covering the period 1980–2012. The Pedroni (1999, 2004), Kao(1999) as well as Westerlund(2007) panel cointegration tests indicate that there is a long-run equilibrium relationship between real GDP, renewable energy consumption, non-renewable energy consumption, real gross fixed capital for...

  12. Balanço de energia em vinhedo de 'Niagara Rosada' Energy balance on 'Niagara Rosada' vineyard

    Directory of Open Access Journals (Sweden)

    José Ricardo Macedo Pezzopane

    2003-01-01

    Full Text Available O método do balanço de energia foi utilizado para caracterizar a variação horária do saldo de radiação e dos fluxos de calor latente, sensível e no solo, em vinhedo cultivado com a cultivar NiagaraRosada', conduzida no sistema de espaldeira, em Jundiaí (SP. Além disso, foram determinadas as relações entre o saldo de radiação (SR no vinhedo e a radiação solar global (RG e a partição da energia disponível ao sistema nos fluxos de calor latente (LE, sensível (H e no solo (G. Em um dia característico de período seco, o LE representou 44% do SR e o H, 48%. Em um dia chuvoso, o LE representou 86% do SR e o H, 21%. Em um dia ensolarado, após um período de chuvas, LE e H foram, respectivamente, 68% e 29% do SR. O G foi, em média, 5,7% e 1,3% do SR para as ruas mantidas capinadas e com forro, respectivamente.The energy balance method was used to characterize the hourly variation of the net radiation, latent and sensible fluxes and soil heat flux on a mature vineyard grown at Jundiaí, São Paulo, Brazil. The grapevines, cv. Niagara Rosada, in the vineyard were wrapped to trellis wires, creating compact hedgerows 2 m apart, 1.7 m height and 0.4 wide, with the foliage 1m above the soil surface. Also, the net and incoming radiation relationships and the partioning of the available energy to the system into latent and heat flux, and soil heat flux were determined for the vineyard. During a sunny day (dry period the latent heat flux was 44% of the net radiation and the sensible heat flux, 48%. However during a rainy day, the latent heat flux was 86% of the net radiation and the sensible heat flux, 21%. During a sunny day, after the occurrence of rain, the latent and sensible heat fluxes were, respectively, 68% and 29% of the net radiation. The soil heat flux was 5.7 an 1.3% of the net radiation, for bare soil and mulched rows, respectively.

  13. Brazilian Energy Balance 2016 - calendar year 2015; Balanco energetico nacional 2016 - ano base 2015

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2016-07-01

    The BEB is divided into eight chapters and ten annexes, whose contents are as follow. Chapter 1 - Energy Analysis and Aggregated Data - presents energy highlights per source in 2015 and analyses the evolution of the domestic energy supply and its relationship with economic growth. Chapter 2 - Energy Supply and Demand by Source - has the accountancy, per primary and secondary energy sources, of the production, import, export, variation of stocks, losses, adjustments and total consumption disaggregated per socioeconomic sector in the country. Chapter 3 - Energy Consumption by Sector - presents the final energy consumption classified by primary and secondary source for each sector of the economy. Chapter 4 - Energy Imports and Exports - presents the evolution of the data on the import and export of energy and the dependence on external energy. Chapter 5 - Balance of Transformation Centers - presents the energy balances for the energy transformation centers including their losses. Chapter 6 - Energy Resources and Reserves - has the basic concepts use in the survey of resources and reserves of primary energy sources. Chapter 7 - Energy and Socioeconomics - contains a comparison of energy, economic and population parameters, specific consumption, energy intensities, average prices and spending on petroleum imports. Chapter 8 - State Energy Data - presents energy data for the states by Federal Unit, main energy source production, energy installations, reserves and hydraulic potential. Relating to annexes the current structure is presented bellow: Annex I - Installed Capacity - shows the installed capacity of electricity generation, the installed capacity of Itaipu hydro plant and the installed capacity for oil refining. Annex II - Self-production of Electricity - presents disaggregated data of self-production, considering sources and sectors. Annex III - World Energy Data - presents the main indicators for the production, import, export and consumption per energy source

  14. Reciprocal Compensation to Changes in Dietary Intake and Energy Expenditure within the Concept of Energy Balance123

    OpenAIRE

    Drenowatz, Clemens

    2015-01-01

    An imbalance between energy intake and energy expenditure is the primary etiology for excess weight gain. Increased energy expenditure via exercise and energy restriction via diet are commonly used approaches to induce weight loss. Such behavioral interventions, however, have generally resulted in a smaller than expected weight loss, which in part has been attributed to compensatory adaptations in other components contributing to energy balance. Current research points to a loose coupling bet...

  15. A Survey on an Energy-Efficient and Energy-Balanced Routing Protocol for Wireless Sensor Networks.

    Science.gov (United States)

    Ogundile, Olayinka O; Alfa, Attahiru S

    2017-05-10

    Wireless sensor networks (WSNs) form an important part of industrial application. There has been growing interest in the potential use of WSNs in applications such as environment monitoring, disaster management, health care monitoring, intelligence surveillance and defence reconnaissance. In these applications, the sensor nodes (SNs) are envisaged to be deployed in sizeable numbers in an outlying area, and it is quite difficult to replace these SNs after complete deployment in many scenarios. Therefore, as SNs are predominantly battery powered devices, the energy consumption of the nodes must be properly managed in order to prolong the network lifetime and functionality to a rational time. Different energy-efficient and energy-balanced routing protocols have been proposed in literature over the years. The energy-efficient routing protocols strive to increase the network lifetime by minimizing the energy consumption in each SN. On the other hand, the energy-balanced routing protocols protract the network lifetime by uniformly balancing the energy consumption among the nodes in the network. There have been various survey papers put forward by researchers to review the performance and classify the different energy-efficient routing protocols for WSNs. However, there seems to be no clear survey emphasizing the importance, concepts, and principles of load-balanced energy routing protocols for WSNs. In this paper, we provide a clear picture of both the energy-efficient and energy-balanced routing protocols for WSNs. More importantly, this paper presents an extensive survey of the different state-of-the-art energy-efficient and energy-balanced routing protocols. A taxonomy is introduced in this paper to classify the surveyed energy-efficient and energy-balanced routing protocols based on their proposed mode of communication towards the base station (BS). In addition, we classified these routing protocols based on the solution types or algorithms, and the input decision

  16. A Survey on an Energy-Efficient and Energy-Balanced Routing Protocol for Wireless Sensor Networks

    Science.gov (United States)

    Ogundile, Olayinka O.; Alfa, Attahiru S.

    2017-01-01

    Wireless sensor networks (WSNs) form an important part of industrial application. There has been growing interest in the potential use of WSNs in applications such as environment monitoring, disaster management, health care monitoring, intelligence surveillance and defence reconnaissance. In these applications, the sensor nodes (SNs) are envisaged to be deployed in sizeable numbers in an outlying area, and it is quite difficult to replace these SNs after complete deployment in many scenarios. Therefore, as SNs are predominantly battery powered devices, the energy consumption of the nodes must be properly managed in order to prolong the network lifetime and functionality to a rational time. Different energy-efficient and energy-balanced routing protocols have been proposed in literature over the years. The energy-efficient routing protocols strive to increase the network lifetime by minimizing the energy consumption in each SN. On the other hand, the energy-balanced routing protocols protract the network lifetime by uniformly balancing the energy consumption among the nodes in the network. There have been various survey papers put forward by researchers to review the performance and classify the different energy-efficient routing protocols for WSNs. However, there seems to be no clear survey emphasizing the importance, concepts, and principles of load-balanced energy routing protocols for WSNs. In this paper, we provide a clear picture of both the energy-efficient and energy-balanced routing protocols for WSNs. More importantly, this paper presents an extensive survey of the different state-of-the-art energy-efficient and energy-balanced routing protocols. A taxonomy is introduced in this paper to classify the surveyed energy-efficient and energy-balanced routing protocols based on their proposed mode of communication towards the base station (BS). In addition, we classified these routing protocols based on the solution types or algorithms, and the input decision

  17. Mass balance, energy and exergy analysis of bio-oil production by fast pyrolysis

    Science.gov (United States)

    Mass, energy and exergy balances are analyzed for bio-oil production in a bench scale fast pyrolysis system developed by the USDA’s Agricultural Research Service (ARS) for the processing of commodity crops to fuel intermediates. Because mass balance closure is difficult to achieve due, in part, to ...

  18. Modelling radiation and energy balances with Landsat 8 images under different thermohydrological conditions in the Brazilian semi-arid region

    Science.gov (United States)

    de C. Teixeira, Antônio H.; Leivas, Janice F.; Andrade, Ricardo G.; Hernandez, Fernando B. T.; Momesso, Franco R. A.

    2015-10-01

    Four Landsat 8 images were used together with a net of seven agro-meteorological stations for modelling the large-scale radiation and energy balances in the mixed agro-ecosystems inside a semi-arid area composed by irrigated crops and natural vegetation of the Petrolina municipality, Northeast Brazil, along the year 2014. The SAFER algorithm was used to calculate the latent heat flux (λE), net radiation (Rn) was acquired by the Slob equation, ground heat flux (G) was considered as a fraction of Rn and the sensible flux (H) was retrieved by residue in the energy balance equation. For classifying the vegetation into irrigated crops and natural vegetation, the SUREAL algorithm was applied to determine the surface resistance (rs) and threshold values for rs were used to characterize the energy fluxes from these types of vegetated surfaces. Clearly one could see higher λE from irrigated crops than from natural vegetation with some situations of heat horizontal advection increasing its values until 23% times larger than Rn, with respective average λE ranges of 5.7 (64% of Rn) to 7.9 (79% of Rn) and 0.4 (4% of Rn) to 4.3 (37% of Rn) MJ m-2 d-1. The corresponding H mean values were from 1.8 (18% of Rn) to 3.2 (28% of Rn) and 5.4 (60% of Rn) to 9.2 (94% of Rn) MJ m-2 d-1. Average G pixel values ranged from 0.3 to 0.4 MJ m-2 d-1, representing 3 and 4% of Rn for natural vegetation and irrigated crops, respectively.

  19. The response of surface mass and energy balance of a continental glacier to climate variability, western Qilian Mountains, China

    Science.gov (United States)

    Sun, Weijun; Qin, Xiang; Wang, Yetang; Chen, Jizu; Du, Wentao; Zhang, Tong; Huai, Baojuan

    2017-08-01

    To understand how a continental glacier responds to climate change, it is imperative to quantify the surface energy fluxes and identify factors controlling glacier mass balance using surface energy balance (SEB) model. Light absorbing impurities (LAIs) at the glacial surface can greatly decrease surface albedo and increase glacial melt. An automatic weather station was set up and generated a unique 6-year meteorological dataset for the ablation zone of Laohugou Glacier No. 12. Based on these data, the surface energy budget was calculated and an experiment on the glacial melt process was carried out. The effect of reduced albedo on glacial melting was analyzed. Owing to continuous accumulation of LAIs, the ablation zone had been darkening since 2010. The mean value of surface albedo in melt period (June through September) dropped from 0.52 to 0.43, and the minimum of daily mean value was as small as 0.1. From the records of 2010-2015, keeping the clean ice albedo fixed in the range of 0.3-0.4, LAIs caused an increase of +7.1 to +16 W m-2 of net shortwave radiation and an removal of 1101-2663 mm water equivalent. Calculation with the SEB model showed equivalent increases in glacial melt were obtained by increasing air temperature by 1.3 and 3.2 K, respectively.

  20. Analysing surface energy balance closure and partitioning over a semi-arid savanna FLUXNET site in Skukuza, Kruger National Park, South Africa

    Science.gov (United States)

    Majozi, Nobuhle P.; Mannaerts, Chris M.; Ramoelo, Abel; Mathieu, Renaud; Nickless, Alecia; Verhoef, Wouter

    2017-07-01

    Flux towers provide essential terrestrial climate, water, and radiation budget information needed for environmental monitoring and evaluation of climate change impacts on ecosystems and society in general. They are also intended for calibration and validation of satellite-based Earth observation and monitoring efforts, such as assessment of evapotranspiration from land and vegetation surfaces using surface energy balance approaches. In this paper, 15 years of Skukuza eddy covariance data, i.e. from 2000 to 2014, were analysed for surface energy balance closure (EBC) and partitioning. The surface energy balance closure was evaluated using the ordinary least squares regression (OLS) of turbulent energy fluxes (sensible (H) and latent heat (LE)) against available energy (net radiation (Rn) less soil heat (G)), and the energy balance ratio (EBR). Partitioning of the surface energy during the wet and dry seasons was also investigated, as well as how it is affected by atmospheric vapour pressure deficit (VPD), and net radiation. After filtering years with low-quality data (2004-2008), our results show an overall mean EBR of 0.93. Seasonal variations of EBR also showed the wet season with 1.17 and spring (1.02) being closest to unity, with the dry season (0.70) having the highest imbalance. Nocturnal surface energy closure was very low at 0.26, and this was linked to low friction velocity during night-time, with results showing an increase in closure with increase in friction velocity. The energy partition analysis showed that sensible heat flux is the dominant portion of net radiation, especially between March and October, followed by latent heat flux, and lastly the soil heat flux, and during the wet season where latent heat flux dominated sensible heat flux. An increase in net radiation was characterized by an increase in both LE and H, with LE showing a higher rate of increase than H in the wet season, and the reverse happening during the dry season. An increase in

  1. CO2 balance in production of energy based on biogas

    DEFF Research Database (Denmark)

    Nielsen, Per Sieverts; Holm-Nielsen, J.B.

    1997-01-01

    Biogas is an essential biomass source for achieving a reduction of CO2 emission by 50% in year 2030 in Denmark. The physical potential for biogas production in Denmark is more than 10 times the present biogas production in Denmark. In Denmark the largest part of the biogas production is produced...... of increased transportation distances at large biogas plants on the total CO2 balance of the biogas plant. The advantage of constructing large biogas plants is the cost-effective possibility of using industrial organic waste to increase biogas production. In some cases co-fermentation increases biogas...... production up 100%. The present study evaluate optimal transportation strategies for biogas plants taking CO2 balances into account....

  2. Preliminary Design of a Solar Photovoltaic Array for Net-Zero Energy Buildings at NASA Langley

    Science.gov (United States)

    Cole, Stuart K.; DeYoung, Russell J.

    2012-01-01

    An investigation was conducted to evaluate photovoltaic (solar electric systems) systems for a single building at NASA Langley as a representative case for alternative sustainable power generation. Building 1250 in the Science Directorate is comprised of office and laboratory space, and currently uses approximately 250,000 kW/month of electrical power with a projected use of 200,000 kW/month with additional conservation measures. The installation would be applied towards a goal for having Building 1250 classified as a net-zero energy building as it would produce as much energy as it uses over the course of a year. Based on the facility s electrical demand, a photovoltaic system and associated hardware were characterized to determine the optimal system, and understand the possible impacts from its deployment. The findings of this investigation reveal that the 1.9 MW photovoltaic electrical system provides favorable and robust results. The solar electric system should supply the needed sustainable power solution especially if operation and maintenance of the system will be considered a significant component of the system deployment.

  3. Development of net energy ratio and emission factor for biohydrogen production pathways.

    Science.gov (United States)

    Kabir, Md Ruhul; Kumar, Amit

    2011-10-01

    This study investigates the energy and environmental aspects of producing biohydrogen for bitumen upgrading from a life cycle perspective. Three technologies are studied for biohydrogen production; these include the Battelle Columbus Laboratory (BCL) gasifier, the Gas Technology Institute (GTI) gasifier, and fast pyrolysis. Three different biomass feedstocks are considered including forest residue (FR), whole forest (WF), and agricultural residue (AR). The fast pyrolysis pathway includes two cases: truck transport of bio-oil and pipeline transport of bio-oil. The net energy ratios (NERs) for nine biohydrogen pathways lie in the range of 1.3-9.3. The maximum NER (9.3) is for the FR-based pathway using GTI technology. The GHG emissions lie in the range of 1.20-8.1 kg CO₂ eq/kg H₂. The lowest limit corresponds to the FR-based biohydrogen production pathway using GTI technology. This study also analyzes the intensities for acid rain precursor and ground level ozone precursor. Copyright © 2011 Elsevier Ltd. All rights reserved.

  4. Energy dependence of moments of net-proton multiplicity distributions at RHIC.

    Science.gov (United States)

    Adamczyk, L; Adkins, J K; Agakishiev, G; Aggarwal, M M; Ahammed, Z; Alekseev, I; Alford, J; Anson, C D; Aparin, A; Arkhipkin, D; Aschenauer, E C; Averichev, G S; Balewski, J; Banerjee, A; Barnovska, Z; Beavis, D R; Bellwied, R; Bhasin, A; Bhati, A K; Bhattarai, P; Bichsel, H; Bielcik, J; Bielcikova, J; Bland, L C; Bordyuzhin, I G; Borowski, W; Bouchet, J; Brandin, A V; Brovko, S G; Bültmann, S; Bunzarov, I; Burton, T P; Butterworth, J; Caines, H; Calderón de la Barca Sánchez, M; Cebra, D; Cendejas, R; Cervantes, M C; Chaloupka, P; Chang, Z; Chattopadhyay, S; Chen, H F; Chen, J H; Chen, L; Cheng, J; Cherney, M; Chikanian, A; Christie, W; Chwastowski, J; Codrington, M J M; Corliss, R; Cramer, J G; Crawford, H J; Cui, X; Das, S; Davila Leyva, A; De Silva, L C; Debbe, R R; Dedovich, T G; Deng, J; Derevschikov, A A; Derradi de Souza, R; Dhamija, S; di Ruzza, B; Didenko, L; Dilks, C; Ding, F; Djawotho, P; Dong, X; Drachenberg, J L; Draper, J E; Du, C M; Dunkelberger, L E; Dunlop, J C; Efimov, L G; Engelage, J; Engle, K S; Eppley, G; Eun, L; Evdokimov, O; Fatemi, R; Fazio, S; Fedorisin, J; Filip, P; Finch, E; Fisyak, Y; Flores, C E; Gagliardi, C A; Gangadharan, D R; Garand, D; Geurts, F; Gibson, A; Girard, M; Gliske, S; Grosnick, D; Guo, Y; Gupta, A; Gupta, S; Guryn, W; Haag, B; Hajkova, O; Hamed, A; Han, L-X; Haque, R; Harris, J W; Hays-Wehle, J P; Heppelmann, S; Hirsch, A; Hoffmann, G W; Hofman, D J; Horvat, S; Huang, B; Huang, H Z; Huck, P; Humanic, T J; Igo, G; Jacobs, W W; Jang, H; Judd, E G; Kabana, S; Kalinkin, D; Kang, K; Kauder, K; Ke, H W; Keane, D; Kechechyan, A; Kesich, A; Khan, Z H; Kikola, D P; Kisel, I; Kisiel, A; Koetke, D D; Kollegger, T; Konzer, J; Koralt, I; Korsch, W; Kotchenda, L; Kravtsov, P; Krueger, K; Kulakov, I; Kumar, L; Kycia, R A; Lamont, M A C; Landgraf, J M; Landry, K D; Lauret, J; Lebedev, A; Lednicky, R; Lee, J H; Leight, W; LeVine, M J; Li, C; Li, W; Li, X; Li, X; Li, Y; Li, Z M; Lima, L M; Lisa, M A; Liu, F; Ljubicic, T; Llope, W J; Longacre, R S; Luo, X; Ma, G L; Ma, Y G; Madagodagettige Don, D M M D; Mahapatra, D P; Majka, R; Margetis, S; Markert, C; Masui, H; Matis, H S; McDonald, D; McShane, T S; Minaev, N G; Mioduszewski, S; Mohanty, B; Mondal, M M; Morozov, D A; Munhoz, M G; Mustafa, M K; Nandi, B K; Nasim, Md; Nayak, T K; Nelson, J M; Nogach, L V; Noh, S Y; Novak, J; Nurushev, S B; Odyniec, G; Ogawa, A; Oh, K; Ohlson, A; Okorokov, V; Oldag, E W; Oliveira, R A N; Pachr, M; Page, B S; Pal, S K; Pan, Y X; Pandit, Y; Panebratsev, Y; Pawlak, T; Pawlik, B; Pei, H; Perkins, C; Peryt, W; Peterson, A; Pile, P; Planinic, M; Pluta, J; Plyku, D; Poljak, N; Porter, J; Poskanzer, A M; Pruthi, N K; Przybycien, M; Pujahari, P R; Putschke, J; Qiu, H; Quintero, A; Ramachandran, S; Raniwala, R; Raniwala, S; Ray, R L; Riley, C K; Ritter, H G; Roberts, J B; Rogachevskiy, O V; Romero, J L; Ross, J F; Roy, A; Ruan, L; Rusnak, J; Sahoo, N R; Sahu, P K; Sakrejda, I; Salur, S; Sandacz, A; Sandweiss, J; Sangaline, E; Sarkar, A; Schambach, J; Scharenberg, R P; Schmah, A M; Schmidke, W B; Schmitz, N; Seger, J; Seyboth, P; Shah, N; Shahaliev, E; Shanmuganathan, P V; Shao, M; Sharma, B; Shen, W Q; Shi, S S; Shou, Q Y; Sichtermann, E P; Singaraju, R N; Skoby, M J; Smirnov, D; Smirnov, N; Solanki, D; Sorensen, P; deSouza, U G; Spinka, H M; Srivastava, B; Stanislaus, T D S; Stevens, J R; Stock, R; Strikhanov, M; Stringfellow, B; Suaide, A A P; Sumbera, M; Sun, X; Sun, X M; Sun, Y; Sun, Z; Surrow, B; Svirida, D N; Symons, T J M; Szanto de Toledo, A; Takahashi, J; Tang, A H; Tang, Z; Tarnowsky, T; Thomas, J H; Timmins, A R; Tlusty, D; Tokarev, M; Trentalange, S; Tribble, R E; Tribedy, P; Trzeciak, B A; Tsai, O D; Turnau, J; Ullrich, T; Underwood, D G; Van Buren, G; van Nieuwenhuizen, G; Vanfossen, J A; Varma, R; Vasconcelos, G M S; Vasiliev, A N; Vertesi, R; Videbæk, F; Viyogi, Y P; Vokal, S; Voloshin, S A; Vossen, A; Wada, M; Walker, M; Wang, F; Wang, G; Wang, H; Wang, J S; Wang, X L; Wang, Y; Wang, Y; Webb, G; Webb, J C; Westfall, G D; Wieman, H; Wissink, S W; Witt, R; Wu, Y F; Xiao, Z; Xie, W; Xin, K; Xu, H; Xu, N; Xu, Q H; Xu, Y; Xu, Z; Yan, W; Yang, C; Yang, Y; Yang, Y; Ye, Z; Yepes, P; Yi, L; Yip, K; Yoo, I-K; Zawisza, Y; Zbroszczyk, H; Zha, W; Zhang, J B; Zhang, S; Zhang, X P; Zhang, Y; Zhang, Z P; Zhao, F; Zhao, J; Zhong, C; Zhu, X; Zhu, Y H; Zoulkarneeva, Y; Zyzak, M

    2014-01-24

    We report the beam energy (sqrt[sNN]=7.7-200  GeV) and collision centrality dependence of the mean (M), standard deviation (σ), skewness (S), and kurtosis (κ) of the net-proton multiplicity distributions in Au+Au collisions. The measurements are carried out by the STAR experiment at midrapidity (|y|<0.5) and within the transverse momentum range 0.4Energy Scan program at the Relativistic Heavy Ion Collider. These measurements are important for understanding the quantum chromodynamic phase diagram. The products of the moments, Sσ and κσ2, are sensitive to the correlation length of the hot and dense medium created in the collisions and are related to the ratios of baryon number susceptibilities of corresponding orders. The products of moments are found to have values significantly below the Skellam expectation and close to expectations based on independent proton and antiproton production. The measurements are compared to a transport model calculation to understand the effect of acceptance and baryon number conservation and also to a hadron resonance gas model.

  5. Explaining the Microtubule Energy Balance: Contributions Due to Dipole Moments, Charges, van der Waals and Solvation Energy.

    Science.gov (United States)

    Ayoub, Ahmed Taha; Staelens, Michael; Prunotto, Alessio; Deriu, Marco A; Danani, Andrea; Klobukowski, Mariusz; Tuszynski, Jack Adam

    2017-09-22

    Microtubules are the main components of mitotic spindles, and are the pillars of the cellular cytoskeleton. They perform most of their cellular functions by virtue of their unique dynamic instability processes which alternate between polymerization and depolymerization phases. This in turn is driven by a precise balance between attraction and repulsion forces between the constituents of microtubules (MTs)-tubulin dimers. Therefore, it is critically important to know what contributions result in a balance of the interaction energy among tubulin dimers that make up microtubules and what interactions may tip this balance toward or away from a stable polymerized state of tubulin. In this paper, we calculate the dipole-dipole interaction energy between tubulin dimers in a microtubule as part of the various contributions to the energy balance. We also compare the remaining contributions to the interaction energies between tubulin dimers and establish a balance between stabilizing and destabilizing components, including the van der Waals, electrostatic, and solvent-accessible surface area energies. The energy balance shows that the GTP-capped tip of the seam at the plus end of microtubules is stabilized only by - 9 kcal/mol, which can be completely reversed by the hydrolysis of a single GTP molecule, which releases + 14 kcal/mol and destabilizes the seam by an excess of + 5 kcal/mol. This triggers the breakdown of microtubules and initiates a disassembly phase which is aptly called a catastrophe.

  6. Explaining the Microtubule Energy Balance: Contributions Due to Dipole Moments, Charges, van der Waals and Solvation Energy

    Directory of Open Access Journals (Sweden)

    Ahmed Taha Ayoub

    2017-09-01

    Full Text Available Microtubules are the main components of mitotic spindles, and are the pillars of the cellular cytoskeleton. They perform most of their cellular functions by virtue of their unique dynamic instability processes which alternate between polymerization and depolymerization phases. This in turn is driven by a precise balance between attraction and repulsion forces between the constituents of microtubules (MTs—tubulin dimers. Therefore, it is critically important to know what contributions result in a balance of the interaction energy among tubulin dimers that make up microtubules and what interactions may tip this balance toward or away from a stable polymerized state of tubulin. In this paper, we calculate the dipole–dipole interaction energy between tubulin dimers in a microtubule as part of the various contributions to the energy balance. We also compare the remaining contributions to the interaction energies between tubulin dimers and establish a balance between stabilizing and destabilizing components, including the van der Waals, electrostatic, and solvent-accessible surface area energies. The energy balance shows that the GTP-capped tip of the seam at the plus end of microtubules is stabilized only by − 9 kcal/mol, which can be completely reversed by the hydrolysis of a single GTP molecule, which releases + 14 kcal/mol and destabilizes the seam by an excess of + 5 kcal/mol. This triggers the breakdown of microtubules and initiates a disassembly phase which is aptly called a catastrophe.

  7. Energy balance in laser-irradiated vaporizing droplets.

    Science.gov (United States)

    Zardecki, A; Armstrong, R L

    1988-09-01

    The interactions of vaporizing aerosols with a high energy laser beam are analyzed in the diffusive vaporization regime. This is the regime in which diffusive mass transport and conductive energy transport dominate the aerosol-beam interactions. A numerical analysis of the coupled aerosol-beam equations allows us to compute the energy conversion of the incident laser pulse. The plots showing the functional form of the pulse shape and the fractional energy conversion are given to illustrate the interactions for a wide range of pulse energies. A new term describing the droplet radius shrinking in time, similar in form to that recently analyzed by Davies and Brock, is included.

  8. Potential evaporation estimation through an unstressed surface-energy balance and its sensitivity to climate change

    Science.gov (United States)

    Barella-Ortiz, A.; Polcher, J.; Tuzet, A.; Laval, K.

    2013-11-01

    Potential evaporation (ETP) is a basic input for many hydrological and agronomic models, as well as a key variable in most actual evaporation estimations. It has been approached through several diffusive and energy balance methods, out of which the Penman-Monteith equation is recommended as the standard one. In order to deal with the diffusive approach, ETP must be estimated at a sub-diurnal frequency, as currently done in land surface models (LSMs). This study presents an improved method, developed in the ORCHIDEE LSM, which consists of estimating ETP through an unstressed surface-energy balance (USEB method). The results confirm the quality of the estimation which is currently implemented in the model (Milly, 1992). The ETP underlying the reference evaporation proposed by the Food and Agriculture Organization, FAO, (computed at a daily time step) has also been analysed and compared. First, a comparison for a reference period under current climate conditions shows that USEB and FAO's ETP estimations differ, especially in arid areas. However, they produce similar values when the FAO's assumption of neutral stability conditions is relaxed, by replacing FAO's aerodynamic resistance by that of the model's. Furthermore, if the vapour pressure deficit (VPD) estimated for the FAO's equation, is substituted by ORCHIDEE's VPD or its humidity gradient, the agreement between the daily mean estimates of ETP is further improved. In a second step, ETP's sensitivity to climate change is assessed by comparing trends in these formulations for the 21st century. It is found that the USEB method shows a higher sensitivity than the FAO's. Both VPD and the model's humidity gradient, as well as the aerodynamic resistance have been identified as key parameters in governing ETP trends. Finally, the sensitivity study is extended to two empirical approximations based on net radiation and mass transfer (Priestley-Taylor and Rohwer, respectively). The sensitivity of these ETP estimates is

  9. Potential Evaporation Computation through an Unstressed Surface Energy Balance and its Sensitivity to Climate Change Effect

    Science.gov (United States)

    Barella-Ortiz, Anaïs; Polcher, Jan; Tuzet, Andrée; Laval, Katia

    2013-04-01

    Potential evaporation (ETP) is a basic input for hydrological and agronomic models, as well as a key variable in most actual evaporation estimations. It has been approached through several diffusive and energy balance methods, out of which the Penman-Monteith equation is recommended as the standard one. In order to deal with the diffusive approach, ETP must be estimated at a sub-diurnal frequency, as currently done in land surface models (LSM). This study presents an improved method, developed in the ORCHIDEE LSM, which consists in estimating ETP through an unstressed surface energy balance (USEB method). The values provided confirm the quality of the estimation which is currently implemented (Milly, 1992). ETP has also been estimated using a reference equation (computed at a daily time step) provided by the Food and Agriculture Organization (FAO). In the first place, a comparison for a reference period of 11 years shows that both formulations differ, specially in arid areas. However, they supply similar values when FAO's assumption of neutral stability conditions is relaxed, by replacing FAO's aerodynamic resistance by the model's one. Additionally, if the vapour pressure deficit (VPD) is also substituted by either ORCHIDEE's VPD or its humidity gradient, the daily mean estimate is further improved. ETP's sensitivity to climate change is assessed comparing trends in both formulations for the 21st Century. It is found that the USEB method shows a higher sensitivity mainly due to FAO's assumption of neutral stability conditions and to a lesser extent, to the approximation proposed for the VPD. Both FAO's VPD and the model's humidity gradient, as well as ORCHIDEE's aerodynamic resistance have been identified as key parameters in governing ETP trends. Finally, the sensitivity study is extended to 3 empirical approximations based on temperature, net radiation and mass transfer (Hargreaves, Priestley - Taylor and Rohwer, respectively). When compared to the USEB method

  10. Developmental programming of energy balance regulation: Is physical activity more "programmable" than food intake

    Science.gov (United States)

    Extensive human and animal model data show that environmental influences during critical periods of prenatal and early postnatal development can cause persistent alterations in energy balance regulation. Although a potentially important factor in the worldwide obesity epidemic, the fundamental mecha...

  11. The Gut and Energy Balance: Visceral Allies in the Obesity Wars

    National Research Council Canada - National Science Library

    Michael K. Badman; Jeffrey S. Flier

    2005-01-01

    .... The gut, the pancreatic islets of Langerhans, elements in the portal vasculature, and even visceral adipose tissue communicate with the controllers of energy balance in the brain by means of neural...

  12. Multiple behavior interventions to prevent substance abuse and increase energy balance behaviors in middle school students

    National Research Council Canada - National Science Library

    Velicer, Wayne F; Redding, Colleen A; Paiva, Andrea L; Mauriello, Leanne M; Blissmer, Bryan; Oatley, Karin; Meier, Kathryn S; Babbin, Steven F; McGee, Heather; Prochaska, James O; Burditt, Caitlin; Fernandez, Anne C

    2013-01-01

    This study examined the effectiveness of two transtheoretical model-tailored, computer-delivered interventions designed to impact multiple substance use or energy balance behaviors in a middle school...

  13. Sleep restriction is not associated with a positive energy balance in adolescent boys

    DEFF Research Database (Denmark)

    Klingenberg, Lars; Chaput, Jean-Philippe; Holmbäck, Ulf

    2012-01-01

    A short sleep (SS) duration has been linked to obesity in observational studies. However, experimental evidence of the potential mechanisms of sleep restriction on energy balance is conflicting and, to our knowledge, nonexistent in adolescents....

  14. To ingest or rest? Specialized roles of lateral hypothalamic area neurons in coordinating energy balance.

    Science.gov (United States)

    Brown, Juliette A; Woodworth, Hillary L; Leinninger, Gina M

    2015-01-01

    Survival depends on an organism's ability to sense nutrient status and accordingly regulate intake and energy expenditure behaviors. Uncoupling of energy sensing and behavior, however, underlies energy balance disorders such as anorexia or obesity. The hypothalamus regulates energy balance, and in particular the lateral hypothalamic area (LHA) is poised to coordinate peripheral cues of energy status and behaviors that impact weight, such as drinking, locomotor behavior, arousal/sleep and autonomic output. There are several populations of LHA neurons that are defined by their neuropeptide content and contribute to energy balance. LHA neurons that express the neuropeptides melanin-concentrating hormone (MCH) or orexins/hypocretins (OX) are best characterized and these neurons play important roles in regulating ingestion, arousal, locomotor behavior and autonomic function via distinct neuronal circuits. Recently, another population of LHA neurons containing the neuropeptide Neurotensin (Nts) has been implicated in coordinating anorectic stimuli and behavior to regulate hydration and energy balance. Understanding the specific roles of MCH, OX and Nts neurons in harmonizing energy sensing and behavior thus has the potential to inform pharmacological strategies to modify behaviors and treat energy balance disorders.

  15. To Ingest or Rest? Specialized Roles of Lateral Hypothalamic Area Neurons in Coordinating Energy Balance

    Directory of Open Access Journals (Sweden)

    Juliette A. Brown

    2015-02-01

    Full Text Available Survival depends on an organism’s ability to sense nutrient status and accordingly regulate intake and energy expenditure behaviors. Uncoupling of energy sensing and behavior, however, underlies energy balance disorders such as anorexia or obesity. The hypothalamus regulates energy balance, and in particular the lateral hypothalamic area (LHA is poised to coordinate peripheral cues of energy status and behaviors that impact weight, such as drinking, locomotor behavior, arousal/sleep and autonomic output. There are several populations of LHA neurons that are defined by their neuropeptide content and contribute to energy balance. LHA neurons that express the neuropeptides melanin-concentrating hormone (MCH or orexins/hypocretins (OX are best characterized and these neurons play important roles in regulating ingestion, arousal, locomotor behavior and autonomic function via distinct neuronal circuits. Recently, another population of LHA neurons containing the neuropeptide Neurotensin (Nts has been implicated in coordinating anorectic stimuli and behavior to regulate hydration and energy balance. Understanding the specific roles of MCH, OX and Nts neurons in harmonizing energy sensing and behavior thus has the potential to inform pharmacological strategies to modify behaviors and treat energy balance disorders.

  16. Reconnoitering the effect of shallow groundwater on land surface temperature and surface energy balance using MODIS and SEBS

    Directory of Open Access Journals (Sweden)

    F. Alkhaier

    2012-07-01

    Full Text Available The possibility of observing shallow groundwater depth and areal extent using satellite measurements can support groundwater models and vast irrigation systems management. Moreover, these measurements can help to include the effect of shallow groundwater on surface energy balance within land surface models and climate studies, which broadens the methods that yield more reliable and informative results. To examine the capacity of MODIS in detecting the effect of shallow groundwater on land surface temperature and the surface energy balance in an area within Al-Balikh River basin in northern Syria, we studied the interrelationship between in-situ measured water table depths and land surface temperatures measured by MODIS. We, also, used the Surface Energy Balance System (SEBS to calculate surface energy fluxes, evaporative fraction and daily evaporation, and inspected their relationships with water table depths. We found out that the daytime temperature increased while the nighttime temperature decreased when the depth of the water table increased. And, when the water table depth increased, net radiation, latent and ground heat fluxes, evaporative fraction and daily evaporation decreased, while sensible heat flux increased. This concords with the findings of a companion paper (Alkhaier et al., 2012. The observed clear relationships were the result of meeting both conditions that were concluded in the companion paper, i.e. high potential evaporation and big contrast in day-night temperature. Moreover, the prevailing conditions in this study area helped SEBS to yield accurate estimates. Under bare soil conditions and under the prevailing weather conditions, we conclude that MODIS is suitable for detecting the effect of shallow groundwater because it has proper imaging times and adequate sensor accuracy; nevertheless, its coarse spatial resolution is disadvantageous.

  17. International Clean Energy System Using Hydrogen Conversion (WE-NET). subtask 3. Study on the global network; Suiso riyo kokusai clean energy system gijutsu (WE-NET). subtask 3. Global network kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-03-01

    As a part of the WE-NET project, the introduction condition of hydrogen as substituting energy and CO2 reduction effect were analyzed using a global energy model. The WE-NET project aims at global-wide introduction of clean energy by converting abundant renewable clean energy into hydrogen transportable to distant consumers all over the world. The study result in fiscal 1996 is as follows. Undeveloped hydroelectric resources in the world are estimated to be 12 trillion kWh/y equivalent to the existing developed one in the world. Since the cost of the hydroelectric power generation projects over 1000MW in the planning stage is estimated to be 0.02-0.05$/kWh lower than that of other renewable energies, such projects are expected as energy source in the initial stage of the practical WE-NET project. The GREEN model was modified by adding a hydrogen analysis function, and extending an analysis period. The modified model allowed evaluation of the long-term important role of hydrogen energy, in particular, the capability of CO2 gas reduction all over the world. 28 refs., 92 figs., 56 tabs.

  18. Energy Balance of Biogas Production from Microalgae: Effect of Harvesting Method, Multiple Raceways, Scale of Plant and Combined Heat and Power Generation

    Directory of Open Access Journals (Sweden)

    John J. Milledge

    2017-01-01

    Full Text Available A previously-developed mechanistic energy balance model for production of biogas from the anaerobic digestion of microalgal biomass grown in open raceway systems was used to consider the energetic viability of a number of scenarios, and to explore some of the most critical parameters affecting net energy production. The output demonstrated that no single harvesting method of those considered (centrifugation, settlement or flocculation produced an energy output sufficiently greater than operational energy inputs to make microalgal biogas production energetically viable. Combinations of harvesting methods could produce energy outputs 2.3–3.4 times greater than the operational energy inputs. Electrical energy to power pumps, mixers and harvesting systems was 5–8 times greater than the heating energy requirement. If the energy to power the plant is generated locally in a combined heat and power unit, a considerable amount of “low grade” heat will be available that is not required by the process, and for the system to show a net operational energy return this must be exploited. It is concluded that the production of microalgal biogas may be energetically viable, but it is dependent on the effective use of the heat generated by the combustion of biogas in combined heat and power units to show an operational energy return.

  19. Multiple behavior interventions to prevent substance abuse and increase energy balance behaviors in middle school students

    OpenAIRE

    Velicer, Wayne F.; Redding, Colleen A.; Paiva, Andrea L.; Mauriello, Leanne M.; Blissmer, Bryan; Oatley, Karin; Meier, Kathryn S.; Babbin, Steven F.; McGee, Heather; Prochaska, James O.; Burditt, Caitlin; Fernandez, Anne C.

    2013-01-01

    This study examined the effectiveness of two transtheoretical model-tailored, computer-delivered interventions designed to impact multiple substance use or energy balance behaviors in a middle school population recruited in schools. Twenty middle schools in Rhode Island including sixth grade students (N = 4,158) were stratified and randomly assigned by school to either a substance use prevention (decreasing smoking and alcohol) or an energy balance (increasing physical activity, fruit and veg...

  20. Analysis of hohlraum energetics of the SG series and the NIF experiments with energy balance model

    OpenAIRE

    Ren, Guoli; Liu, Jie; Huo, Wenyi; Lan, Ke

    2017-01-01

    The basic energy balance model is applied to analyze the hohlraum energetics data from the Shenguang (SG) series laser facilities and the National Ignition Facility (NIF) experiments published in the past few years. The analysis shows that the overall hohlraum energetics data are in agreement with the energy balance model within 20% deviation. The 20% deviation might be caused by the diversity in hohlraum parameters, such as material, laser pulse, gas filling density, etc. In addition, the NI...

  1. Knowledge of Energy Balance Guidelines and Associated Clinical Care Practices: The U.S. National Survey of Energy Balance Related Care among Primary Care Physicians

    Science.gov (United States)

    Pronk, Nicolaas P.; Krebs-Smith, Susan M.; Galuska, Deborah A.; Liu, Benmei; Kushner, Robert F.; Troiano, Richard P.; Clauser, Steven B.; Ballard-Barbash, Rachel; Smith, Ashley Wilder

    2012-01-01

    Objective To assess primary care physicians’ (PCPs) knowledge of energy balance related guidelines and the association with sociodemographic characteristics and clinical care practices. Method As part of the 2008 U.S. nationally representative National Survey of Energy Balance Related Care among Primary Care Physicians (EB-PCP), 1,776 PCPs from four specialties who treated adults (n=1,060) or children and adolescents (n=716) completed surveys on sociodemographic information, knowledge of energy balance guidelines, and clinical care practices. Results EB-PCP response rate was 64.5%. For PCPs treating children, knowledge of guidelines for healthy BMI percentile, physical activity, and fruit and vegetables intake was 36.5%, 27.0%, and 62.9%, respectively. For PCPs treating adults, knowledge of guidelines for overweight, obesity, physical activity, and fruit and vegetables intake was 81.4%, 81.3%, 70.9%, and 63.5%, respectively. Generally, younger, female physicians were more likely to exhibit correct knowledge. Knowledge of weight-related guidelines was associated with assessment of body mass index (BMI) and use of BMI-for-age growth charts. Conclusion Knowledge of energy balance guidelines among PCPs treating children is low, among PCPs treating adults it appeared high for overweight and obesity-related clinical guidelines and moderate for physical activity and diet, and was mostly unrelated to clinical practices among all PCPs. PMID:22609144

  2. Net soil respiration and greenhouse gas balance along a sequence of forest disturbance to smallholder rubber and oil palm plantations in Sumatra

    Science.gov (United States)

    Khusyu Aini, Fitri; Hergoualc'h, Kristell; Smith, Jo; Verchot, Louis; Martius, Christopher

    2017-04-01

    The rapid increase in demand for land to establish oil palm and rubber plantations has led to the conversion of forests, with potential impacts on greenhouse gas emissions and on climate change. This study evaluates the net greenhouse gas balance following forest change to other land uses, i.e. one year rubber plantation, twenty-year rubber plantation and eight year oil palm plantation on Sumatran mineral soils. None of the plantations had ever been fertilized previously. During this study they were fertilized to provide nitrogen at the recommended rate used by farmers (33.3 kg N ha-1 y-1). The ecosystem stores carbon in litterfall, standing litter biomass (undergrowth vegetation, leaves, twigs, litter on the soil surface), soil organic matter, root biomass, and standing tree biomass. It releases carbon to the atmosphere through soil respiration fluxes, negative values indicating that carbon is stored by the land use change and positive values indicating emissions to the atmosphere. Net soil respiration was assessed using a mass balance approach: standing litter and tree biomass were measured once; the rate of carbon accumulation from standing litter and tree biomass was calculated by dividing the stock by the age of plantation or the time since logging started in the disturbed forest. The carbon accumulation in standing litter, tree biomass in the forest and soil organic matter for all land-uses was estimated from available in the literature. Root biomass for each land-use system was calculated using the root:shoot ratio. The net soil respiration of carbon dioxide from the forest, disturbed forest, one year rubber plantation, twenty-year rubber plantation and oil palm plantation were calculated to be -6 (± 5), 12 (± 6), 11 (± 15), 10 (± 5), 39 (± 7) Mg ha-1 y-1, respectively. Soil nitrous oxide, methane and litterfall were measured for 14 months and respiration fluxes were measured for 5 months across land uses and different seasons. The measured emissions of

  3. The role of sleep duration in the regulation of energy balance: effects on energy intakes and expenditure.

    Science.gov (United States)

    St-Onge, Marie-Pierre

    2013-01-15

    Short sleep duration and obesity are common occurrence in today's society. An extensive literature from cross-sectional and longitudinal epidemiological studies shows a relationship between short sleep and prevalence of obesity and weight gain. However, causality cannot be inferred from such studies. Clinical intervention studies have examined whether reducing sleep in normal sleepers, typically sleeping 7-9 h/night, can affect energy intake, energy expenditure, and endocrine regulators of energy balance. The aim of this review is to evaluate studies that have assessed food intake, energy expenditure, and leptin and ghrelin levels after periods of restricted and normal sleep. Most studies support the notion that restricting sleep increases food intake, but the effects on energy expenditure are mixed. Differences in methodology and component of energy expenditure analyzed may account for the discrepancies. Studies examining the effects of sleep on leptin and ghrelin have provided conflicting results with increased, reduced, or unchanged leptin and ghrelin levels after restricted sleep compared to normal sleep. Energy balance of study participants and potential sex differences may account for the varied results. Studies should strive for constant energy balance and feeding schedules when assessing the role of sleep on hormonal profile. Although studies suggest that restricting sleep may lead to weight gain via increased food intake, research is needed to examine the impact on energy expenditure and endocrine controls. Also, studies have been of short duration, and there is little knowledge on the reverse question: does increasing sleep duration in short sleepers lead to negative energy balance?

  4. Multiple behavior interventions to prevent substance abuse and increase energy balance behaviors in middle school students.

    Science.gov (United States)

    Velicer, Wayne F; Redding, Colleen A; Paiva, Andrea L; Mauriello, Leanne M; Blissmer, Bryan; Oatley, Karin; Meier, Kathryn S; Babbin, Steven F; McGee, Heather; Prochaska, James O; Burditt, Caitlin; Fernandez, Anne C

    2013-03-01

    This study examined the effectiveness of two transtheoretical model-tailored, computer-delivered interventions designed to impact multiple substance use or energy balance behaviors in a middle school population recruited in schools. Twenty middle schools in Rhode Island including sixth grade students (N=4,158) were stratified and randomly assigned by school to either a substance use prevention (decreasing smoking and alcohol) or an energy balance (increasing physical activity, fruit and vegetable consumption, and limiting TV time) intervention group in 2007. Each intervention involved five in-class contacts over a 3-year period with assessments at 12, 24, and 36 months. Main outcomes were analyzed using random effects modeling. In the full energy balance group and in subsamples at risk and not at risk at baseline, strong effects were found for physical activity, healthy diet, and reducing TV time, for both categorical and continuous outcomes. Despite no direct treatment, the energy balance group also showed significantly lower smoking and alcohol use over time than the substance use prevention group. The energy balance intervention demonstrated strong effects across all behaviors over 3 years among middle school students. The substance use prevention intervention was less effective than the energy balance intervention in preventing both smoking and alcohol use over 3 years in middle school students. The lack of a true control group and unrepresented secular trends suggest the need for further study.

  5. On the Linearly-Balanced Kinetic Energy Spectrum

    Science.gov (United States)

    Lu, Huei,-Iin; Robertson, F. R.

    1999-01-01

    It is well known that the earth's atmospheric motion can generally be characterized by the two dimensional quasi-geostrophic approximation, in which the constraints on global integrals of kinetic energy, entrophy and potential vorticity play very important roles in redistributing the wave energy among different scales of motion. Assuming the hypothesis of Kolmogrov's local isotropy, derived a -3 power law of the equilibrium two-dimensional kinetic energy spectrum that entails constant vorticity and zero energy flows from the energy-containing wave number up to the viscous cutoff. In his three dimensional quasi-geostrophic theory, showed that the spectrum function of the vertical scale turbulence - expressible in terms of the available potential energy - possesses the same power law as the two dimensional kinetic energy spectrum. As the slope of kinetic energy spectrum in the inertial range is theoretically related to the predictability of the synoptic scales (Lorenz, 1969), many general circulation models includes a horizontal diffusion to provide reasonable kinetic energy spectra, although the actual power law exhibited in the atmospheric general circulation is controversial. Note that in either the atmospheric modeling or the observational analyses, the proper choice of wave number Index to represent the turbulence scale Is the degree of the Legendre polynomial.

  6. The Role of PVH Circuits in Leptin Action and Energy Balance.

    Science.gov (United States)

    Sutton, Amy K; Myers, Martin G; Olson, David P

    2016-01-01

    Although it has been known for more than a century that the brain controls overall energy balance and adiposity by regulating feeding behavior and energy expenditure, the roles for individual brain regions and neuronal subtypes were not fully understood until recently. This area of research is active, and as such our understanding of the central regulation of energy balance is continually being refined as new details emerge. Much of what we now know stems from the discoveries of leptin and the hypothalamic melanocortin system. Hypothalamic circuits play a crucial role in the control of feeding and energy expenditure, and within the hypothalamus, the arcuate nucleus (ARC) functions as a gateway for hormonal signals of energy balance, such as leptin. It is also well established that the ARC is a primary residence for hypothalamic melanocortinergic neurons. The paraventricular hypothalamic nucleus (PVH) receives direct melanocortin input, along with other integrated signals that affect energy balance, and mediates the majority of hypothalamic output to control both feeding and energy expenditure. Herein, we review in detail the structure and function of the ARC-PVH circuit in mediating leptin signaling and in regulating energy balance.

  7. A novel load balanced energy conservation approach in WSN using biogeography based optimization

    Science.gov (United States)

    Kaushik, Ajay; Indu, S.; Gupta, Daya

    2017-09-01

    Clustering sensor nodes is an effective technique to reduce energy consumption of the sensor nodes and maximize the lifetime of Wireless sensor networks. Balancing load of the cluster head is an important factor in long run operation of WSNs. In this paper we propose a novel load balancing approach using biogeography based optimization (LB-BBO). LB-BBO uses two separate fitness functions to perform load balancing of equal and unequal load respectively. The proposed method is simulated using matlab and compared with existing methods. The proposed method shows better performance than all the previous works implemented for energy conservation in WSN

  8. Competitive cation binding computations of proton balance for reactions of the phosphagen and glycolytic energy systems within skeletal muscle.

    Science.gov (United States)

    Robergs, Robert Andrew

    2017-01-01

    Limited research and data has been published for the H+ coefficients for the metabolites and reactions involved in non-mitochondrial energy metabolism. The purpose of this investigation was to compute the fractional binding of H+, K+, Na+ and Mg2+ to 21 metabolites of skeletal muscle non-mitochondrial energy metabolism, resulting in 104 different metabolite-cation complexes. Fractional binding of H+ to these metabolite-cation complexes were applied to 17 reactions of skeletal muscle non-mitochondrial energy metabolism, and 8 conditions of the glycolytic pathway based on the source of substrate (glycogen vs. glucose), completeness of glycolytic flux, and the end-point of pyruvate vs. lactate. For pH conditions of 6.0 and 7.0, respectively, H+ coefficients (-'ve values = H+ release) for the creatine kinase, adenylate kinase, AMP deaminase and ATPase reactions were 0.8 and 0.97, -0.13 and -0.02, 1.2 and 1.09, and -0.01 and -0.66, respectively. The glycolytic pathway is net H+ releasing, regardless of lactate production, which consumes 1 H+. For glycolysis fueled by glycogen and ending in either pyruvate or lactate, H+ coefficients for pH 6.0 and 7.0 were -3.97 and -2.01 (pyruvate), and -1.96 and -0.01 (lactate), respectively. When starting with glucose, the same conditions result in H+ coefficients of -3.98 and -2.67, and -1.97 and -0.67, respectively. The most H+ releasing reaction of glycolysis is the glyceraldehyde-3-phosphate dehydrogenase reaction, with H+ coefficients for pH 6.0 and 7.0 of -1.58 and -0.76, respectively. Incomplete flux of substrate through glycolysis would increase net H+ release due to the absence of the pyruvate kinase and lactate dehydrogenase reactions, which collectively result in H+ coefficients for pH 6.0 and 7.0 of 1.35 and 1.88, respectively. The data presented provide an extensive reference source for academics and researchers to accurately profile the balance of protons for all metabolites and reactions of non-mitochondrial energy

  9. Competitive cation binding computations of proton balance for reactions of the phosphagen and glycolytic energy systems within skeletal muscle.

    Directory of Open Access Journals (Sweden)

    Robert Andrew Robergs

    Full Text Available Limited research and data has been published for the H+ coefficients for the metabolites and reactions involved in non-mitochondrial energy metabolism. The purpose of this investigation was to compute the fractional binding of H+, K+, Na+ and Mg2+ to 21 metabolites of skeletal muscle non-mitochondrial energy metabolism, resulting in 104 different metabolite-cation complexes. Fractional binding of H+ to these metabolite-cation complexes were applied to 17 reactions of skeletal muscle non-mitochondrial energy metabolism, and 8 conditions of the glycolytic pathway based on the source of substrate (glycogen vs. glucose, completeness of glycolytic flux, and the end-point of pyruvate vs. lactate. For pH conditions of 6.0 and 7.0, respectively, H+ coefficients (-'ve values = H+ release for the creatine kinase, adenylate kinase, AMP deaminase and ATPase reactions were 0.8 and 0.97, -0.13 and -0.02, 1.2 and 1.09, and -0.01 and -0.66, respectively. The glycolytic pathway is net H+ releasing, regardless of lactate production, which consumes 1 H+. For glycolysis fueled by glycogen and ending in either pyruvate or lactate, H+ coefficients for pH 6.0 and 7.0 were -3.97 and -2.01 (pyruvate, and -1.96 and -0.01 (lactate, respectively. When starting with glucose, the same conditions result in H+ coefficients of -3.98 and -2.67, and -1.97 and -0.67, respectively. The most H+ releasing reaction of glycolysis is the glyceraldehyde-3-phosphate dehydrogenase reaction, with H+ coefficients for pH 6.0 and 7.0 of -1.58 and -0.76, respectively. Incomplete flux of substrate through glycolysis would increase net H+ release due to the absence of the pyruvate kinase and lactate dehydrogenase reactions, which collectively result in H+ coefficients for pH 6.0 and 7.0 of 1.35 and 1.88, respectively. The data presented provide an extensive reference source for academics and researchers to accurately profile the balance of protons for all metabolites and reactions of non

  10. Arc tracking energy balance for copper and aluminum aeronautic cables

    Science.gov (United States)

    André, T.; Valensi, F.; Teulet, P.; Cressault, Y.; Zink, T.; Caussé, R.

    2017-04-01

    Arc tracking tests have been carried out between two voluntarily damaged aeronautic cables. Copper or aluminum conductors have been exposed to short circuits under alternating current. Various data have been recorded (arc voltage and current, radiated power and ablated mass), enabling to determine a power balance, in which every contribution is estimated. The total power is mainly transferred to the cables (between 50 and 65%, depending on the current and the cable type), and causes the melting and partial vaporization of the metallic core and insulating material, or is conducted or radiated. The other part is deposited into the arc column, being either radiated, convected or conducted.

  11. Neuronal energy-sensing pathway promotes energy balance by modulating disease tolerance.

    Science.gov (United States)

    Shen, Run; Wang, Biao; Giribaldi, Maria G; Ayres, Janelle; Thomas, John B; Montminy, Marc

    2016-06-07

    The starvation-inducible coactivator cAMP response element binding protein (CREB)-cAMP-regulated transcription coactivator (Crtc) has been shown to promote starvation resistance in Drosophila by up-regulating CREB target gene expression in neurons, although the underlying mechanism is unclear. We found that Crtc and its binding partner CREB enhance energy homeostasis by stimulating the expression of short neuropeptide F (sNPF), an ortholog of mammalian neuropeptide Y, which we show here is a direct target of CREB and Crtc. Neuronal sNPF was found to promote energy homeostasis via gut enterocyte sNPF receptors, which appear to maintain gut epithelial integrity. Loss of Crtc-sNPF signaling disrupted epithelial tight junctions, allowing resident gut flora to promote chronic increases in antimicrobial peptide (AMP) gene expression that compromised energy balance. Growth on germ-free food reduced AMP gene expression and rescued starvation sensitivity in Crtc mutant flies. Overexpression of Crtc or sNPF in neurons of wild-type flies dampens the gut immune response and enhances starvation resistance. Our results reveal a previously unidentified tolerance defense strategy involving a brain-gut pathway that maintains homeostasis through its effects on epithelial integrity.

  12. Balancing Bio-energy Cropping Benefits and Water Quality Impacts

    NARCIS (Netherlands)

    Eiswerth, M.E.; Kooten, van G.C.

    2010-01-01

    The relationship between bio-energy feedstock production and water quality has received little attention from economists. Here, an optimal control model is used to determine the optimal amount of land to convert to the production of energy feedstocks, specifically ethanol corn, taking into account

  13. A Governance Perspective on Net Zero Energy Building Niche Development in India: The Case of New Delhi

    NARCIS (Netherlands)

    Jain, Mansi; Hoppe, T.; Bressers, Hans

    2017-01-01

    The net zero-energy building (NZEB) concept has recently gained prominence worldwide. Large scale adoption and implementation of NZEBs would potentially contribute greatly to greening of the building sector. However, it is still at a nascent stage of niche formation. This paper aims to assess the

  14. Brazilian national energy balance 2007. Calendar year 2006[Includes executive summary 2007]; Balanco energetico nacional 2007. Ano base 2006

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2007-07-01

    This document reports the activities of the Ministry of Mine and Energy, during the calendar year 2006 as follows: energy analysis and aggregated data; supply and demand of energy according to source; energy consumption according to sector; energy external trading; transformation center balance; energy resources and reserves; energy and social economics; state energy data; installed capacity; energy world data.

  15. Solar energy research and development: program balance. Annex, Volume II

    Energy Technology Data Exchange (ETDEWEB)

    None

    1978-02-01

    Each of the seven solar energy technologies that have been assessed in the study are treated: photovoltaic devices, solar thermal power systems, wind energy systems, solar heating and cooling systems, agricultural and industrial heat processes, biomass conversion technologies, and ocean thermal energy conversion systems. A brief technical overview of storage for solar electric technologies is presented and some principles concerning how different levels of success on electrical storage can affect the commercial viability of solar electric options are discussed. A description is given of the solar penetration model that was developed and applied as an analytical tool in the study. This computer model has served the primary purpose of evaluating the competiveness of the solar energy systems in the markets in which they are expected to compete relative to that of the alternative energy sources. This is done under a variety of energy supply, demand, and price conditions. The seven sections treating the solar energy technologies contain discussions on each of six subject areas: description of the technology; economic projections; the potential contribution of the technology in different marketplaces; environmental considerations; international potential; and the present and possible future emphases within the RD and D program. The priority item for each of the technology sections has been the documentation of the economic projections.

  16. The Role of Sleep Duration in the Regulation of Energy Balance: Effects on Energy Intakes and Expenditure

    Science.gov (United States)

    St-Onge, Marie-Pierre

    2013-01-01

    Short sleep duration and obesity are common occurrence in today's society. An extensive literature from cross-sectional and longitudinal epidemiological studies shows a relationship between short sleep and prevalence of obesity and weight gain. However, causality cannot be inferred from such studies. Clinical intervention studies have examined whether reducing sleep in normal sleepers, typically sleeping 7–9 h/night, can affect energy intake, energy expenditure, and endocrine regulators of energy balance. The aim of this review is to evaluate studies that have assessed food intake, energy expenditure, and leptin and ghrelin levels after periods of restricted and normal sleep. Most studies support the notion that restricting sleep increases food intake, but the effects on energy expenditure are mixed. Differences in methodology and component of energy expenditure analyzed may account for the discrepancies. Studies examining the effects of sleep on leptin and ghrelin have provided conflicting results with increased, reduced, or unchanged leptin and ghrelin levels after restricted sleep compared to normal sleep. Energy balance of study participants and potential sex differences may account for the varied results. Studies should strive for constant energy balance and feeding schedules when assessing the role of sleep on hormonal profile. Although studies suggest that restricting sleep may lead to weight gain via increased food intake, research is needed to examine the impact on energy expenditure and endocrine controls. Also, studies have been of short duration, and there is little knowledge on the reverse question: does increasing sleep duration in short sleepers lead to negative energy balance? Citation: St-Onge MP. The role of sleep duration in the regulation of energy balance: effects on energy intakes and expenditure. J Clin Sleep Med 2013;9(1):73–80. PMID:23319909

  17. Effects of 3-nitrooxypropanol on methane emission, digestion, and energy and nitrogen balance of lactating dairy cows.

    Science.gov (United States)

    Reynolds, C K; Humphries, D J; Kirton, P; Kindermann, M; Duval, S; Steinberg, W

    2014-01-01

    The objective was to measure effects of 3-nitrooxypropanol (3 NP) on methane production of lactating dairy cows and any associated changes in digestion and energy and N metabolism. Six Holstein-Friesian dairy cows in mid-lactation were fed twice daily a total mixed ration with maize silage as the primary forage source. Cows received 1 of 3 treatments using an experimental design based on two 3 × 3 Latin squares with 5-wk periods. Treatments were a control placebo or 500 or 2,500 mg/d of 3 NP delivered directly into the rumen, via the rumen fistula, in equal doses before each feeding. Measurements of methane production and energy and N balance were obtained during wk 5 of each period using respiration calorimeters and digestion trials. Measurements of rumen pH (48 h) and postprandial volatile fatty acid and ammonia concentrations were made at the end of wk 4. Daily methane production was reduced by 3 NP, but the effects were not dose dependent (reductions of 6.6 and 9.8% for 500 and 2,500 mg/d, respectively). Dosing 3 NP had a transitory inhibitory effect on methane production, which may have been due to the product leaving the rumen in liquid outflow or through absorption or metabolism. Changes in rumen concentrations of volatile fatty acids indicated that the pattern of rumen fermentation was affected by both doses of the product, with a decrease in acetate:propionate ratio observed, but that acetate production was inhibited by the higher dose. Dry matter, organic matter, acid detergent fiber, N, and energy digestibility were reduced at the higher dose of the product. The decrease in digestible energy supply was not completely countered by the decrease in methane excretion such that metabolizable energy supply, metabolizable energy concentration of the diet, and net energy balance (milk plus tissue energy) were reduced by the highest dose of 3 NP. Similarly, the decrease in N digestibility at the higher dose of the product was associated with a decrease in body N

  18. Balancing Renewable Electricity Energy Storage, Demand Side Management, and Network Extension from an Interdisciplinary Perspective

    CERN Document Server

    Droste-Franke, Bert; Rehtanz, Christian; Sauer, Dirk Uwe; Schneider, Jens-Peter; Schreurs, Miranda; Ziesemer, Thomas

    2012-01-01

    A significant problem of integrating renewable energies into the electricity system is the temporally fluctuating energy production by wind and solar power plants. Thus, in order to meet the ambitious long-term targets on CO2 emission reduction, long-term viable low-carbon options for balancing electricity will be needed. This interdisciplinary study analyses published future energy scenarios in order to get an impression of the required balancing capacities and shows which framework conditions should be modified to support their realisation. The authors combine their perspectives from energy engineering, technology assessment, political science, economical science and jurisprudence and address science, politics, actors in the energy sector and the interested public. Respectively, requirements for the balancing systems are analysed, considering the case of Germany as a large country with high ambitions to reduce greenhouse gas emissions. Additionally, an approach to investigate the optimal design of the techn...

  19. Electrochemical energy storage for renewable sources and grid balancing

    CERN Document Server

    Moseley, Patrick T

    2015-01-01

    Electricity from renewable sources of energy is plagued by fluctuations (due to variations in wind strength or the intensity of insolation) resulting in a lack of stability if the energy supplied from such sources is used in 'real time'. An important solution to this problem is to store the energy electrochemically (in a secondary battery or in hydrogen and its derivatives) and to make use of it in a controlled fashion at some time after it has been initially gathered and stored. Electrochemical battery storage systems are the major technologies for decentralized storage systems and hydrogen

  20. Net technical assessment

    OpenAIRE

    Wegmann, David G.

    1989-01-01

    Approved for public release; distribution is unlimited. The present and near term military balance of power between the U.S. and the Soviet Union can be expressed in a variety of net assessments. One can examine the strategic nuclear balance, the conventional balance in Europe, the maritime balance, and many others. Such assessments are essential not only for policy making but for arms control purposes and future force structure planning. However, to project the future military balance, on...

  1. Cost Control Best Practices for Net Zero Energy Building Projects: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Leach, M.; Pless, S.; Torcellini, P.

    2014-02-01

    For net zero energy (NZE) buildings to become the norm in commercial construction, it will be necessary to design and construct these buildings cost effectively. While industry leaders have developed workflows (for procurement, design, and construction) to achieve cost-effective NZE buildings for certain cases, the expertise embodied in those workflows has limited penetration within the commercial building sector. Documenting cost control best practices of industry leaders in NZE and packaging those strategies for adoption by the commercial building sector will help make the business case for NZE. Furthermore, it will promote market uptake of the innovative technologies and design approaches needed to achieve NZE. This paper summarizes successful cost control strategies for NZE procurement, design, and construction that key industry users (such as building owners, architects, and designers) can incorporate into their everyday workflows. It will also evaluate the current state of NZE economics and propose a path forward for greater market penetration of NZE buildings. By demonstrating how to combine NZE technologies and design approaches into an overall efficiency package that can be implemented at minimal (zero, in certain cases) incremental capital cost, the domain of NZE design and construction can be expanded from a niche market to the commercial construction mainstream.

  2. Balancing act: Government roles in an energy conservation network

    NARCIS (Netherlands)

    Peterman, A.; Kourula, A.; Levitt, R.

    2014-01-01

    Government-led interorganizational alliance networks present a sensible opportunity to overcome many societal challenges through collaborative governance. In particular, few researchers have studied alliance networks in the field of energy conservation in commercial buildings—a sector with unique

  3. Surface-layer turbulence, energy balance and links to atmospheric circulations over a mountain glacier in the French Alps

    Science.gov (United States)

    Litt, Maxime; Sicart, Jean-Emmanuel; Six, Delphine; Wagnon, Patrick; Helgason, Warren D.

    2017-04-01

    Over Saint-Sorlin Glacier in the French Alps (45° N, 6.1° E; ˜ 3 km2) in summer, we study the atmospheric surface-layer dynamics, turbulent fluxes, their uncertainties and their impact on surface energy balance (SEB) melt estimates. Results are classified with regard to large-scale forcing. We use high-frequency eddy-covariance data and mean air-temperature and wind-speed vertical profiles, collected in 2006 and 2009 in the glacier's atmospheric surface layer. We evaluate the turbulent fluxes with the eddy-covariance (sonic) and the profile method, and random errors and parametric uncertainties are evaluated by including different stability corrections and assuming different values for surface roughness lengths. For weak synoptic forcing, local thermal effects dominate the wind circulation. On the glacier, weak katabatic flows with a wind-speed maximum at low height (2-3 m) are detected 71 % of the time and are generally associated with small turbulent kinetic energy (TKE) and small net turbulent fluxes. Radiative fluxes dominate the SEB. When the large-scale forcing is strong, the wind in the valley aligns with the glacier flow, intense downslope flows are observed, no wind-speed maximum is visible below 5 m, and TKE and net turbulent fluxes are often intense. The net turbulent fluxes contribute significantly to the SEB. The surface-layer turbulence production is probably not at equilibrium with dissipation because of interactions of large-scale orographic disturbances with the flow when the forcing is strong or low-frequency oscillations of the katabatic flow when the forcing is weak. In weak forcing when TKE is low, all turbulent fluxes calculation methods provide similar fluxes. In strong forcing when TKE is large, the choice of roughness lengths impacts strongly the net turbulent fluxes from the profile method fluxes and their uncertainties. However, the uncertainty on the total SEB remains too high with regard to the net observed melt to be able to

  4. The ANIBES Study on Energy Balance in Spain: Design, Protocol and Methodology

    OpenAIRE

    Emma Ruiz; José Manuel Ávila; Adrián Castillo; Teresa Valero; Susana del Pozo; Paula Rodriguez; Javier Aranceta Bartrina; Ángel Gil; Marcela González-Gross; Rosa M. Ortega; Lluis Serra-Majem; Gregorio Varela-Moreiras

    2015-01-01

    Energy Balance (EB) is an important topic to understand how an imbalance in its main determinants (energy intake and consumption) may lead to inappropriate weight gain, considered to be “dynamic” and not “static”. There are no studies to evaluate EB in Spain, and new technologies reveal themselves as key tools to solve common problems to precisely quantify energy consumption and expenditure at population level. The overall purpose of the ANIBES (“Anthropometry, Intake and Energy Balance”) Stu...

  5. Energy Balance Alterations Due to Cropland Conversion in a Tropical Montane Environment: Shaded Coffee to Sugarcane

    Science.gov (United States)

    Alvarado-Barrientos, M. S.; Holwerda, F.; Salazar-Martinez, D.

    2014-12-01

    Although land use change (LUC) is an important driver of changes in climate, very limited field observations of atmosphere-landscape interactions exist in tropical montane zones to examine the extent to which LUCs affect climate locally and regionally. The lack of ground observations hampers the evaluation of satellite-derived datasets of land surface parameters as well as the validation of regional climate models. The first results of an ongoing study of the climate effects of a LUC trajectory in the lower montane region (1200 m a.s.l.) of central Veracruz, Mexico, are presented. The radiation balance, turbulent fluxes and soil heat flux were measured in order to obtain field-derived land surface parameters (albedo and Bowen ratio) of two contrasting land uses: shaded coffee (CO) and sugarcane (SU) plantations. Measurements were conducted on days representing different seasons and crop stages during 2014: cold-dry (January), warm-dry (March) and warm-wet (July). Average noon-time albedo was higher for SU than for CO (0.14 vs. 0.11). Soil heat flux was on average 13% and 12% of net radiation for SU and CO, respectively. Preliminary turbulent flux calculations indicate that noon-time Bowen ratio was higher for sugar cane (range: 1.0-1.5) compared to shaded coffee (range: 0.5-1.0). Seasonal (and crop-stage) changes affected the surface parameters of SU mostly. For example, the SU Bowen ratio increased with decreasing soil moisture, indicating soil moisture limitation for transpiration reducing latent heat flux. In contrast, the shaded coffee Bowen ratio remained relatively constant across measuring periods. The energy balance closure was 80% (pending complete eddy covariance data corrections). These results indicate that the conversion of shaded coffee to sugarcane result in a drier and hotter lower atmosphere. Next steps include examining the implications of these local changes for regional climate, with special attention to cloud formation, using a regional model

  6. Effects of dietary energy source on energy balance, metabolites and reproduction variables in dairy cows in early lactation

    NARCIS (Netherlands)

    Knegsel, van A.T.M.; Brand, van den H.; Dijkstra, J.; Kemp, B.

    2007-01-01

    This paper summarizes three recent studies by the same authors with the objective to study the effect of dietary energy source on the energy balance (EB) and risk for metabolic and reproductive disorders in dairy cows in early lactation. The first study, a literature survey, illustrated that feeding

  7. Effect of dry period length and dietary energy source on energy balance, milk yield, and milk composition of dairy cows

    NARCIS (Netherlands)

    Knegsel, van A.T.M.; Remmelink, G.J.; Jorjong, S.; Fievez, V.; Kemp, B.

    2014-01-01

    The objective of this study was to evaluate the effects of dry period length and dietary energy source in early lactation on milk production, feed intake, and energy balance (EB) of dairy cows. Holstein-Friesian dairy cows (60 primiparous and 108 multiparous) were randomly assigned to dry period

  8. Quantity of dietary protein intake, but not pattern of intake, affects net protein balance primarily through differences in protein synthesis in older adults.

    Science.gov (United States)

    Kim, Il-Young; Schutzler, Scott; Schrader, Amy; Spencer, Horace; Kortebein, Patrick; Deutz, Nicolaas E P; Wolfe, Robert R; Ferrando, Arny A

    2015-01-01

    To examine whole body protein turnover and muscle protein fractional synthesis rate (MPS) following ingestions of protein in mixed meals at two doses of protein and two intake patterns, 20 healthy older adult subjects (52-75 yr) participated in one of four groups in a randomized clinical trial: a level of protein intake of 0.8 g (1RDA) or 1.5 g·kg(-1)·day(-1) (∼2RDA) with uneven (U: 15/20/65%) or even distribution (E: 33/33/33%) patterns of intake for breakfast, lunch, and dinner over the day (1RDA-U, 1RDA-E, 2RDA-U, or 2RDA-E). Subjects were studied with primed continuous infusions of L-[(2)H5]phenylalanine and L-[(2)H2]tyrosine on day 4 following 3 days of diet habituation. Whole body protein kinetics [protein synthesis (PS), breakdown, and net balance (NB)] were expressed as changes from the fasted to the fed states. Positive NB was achieved at both protein levels, but NB was greater in 2RDA vs. 1RDA (94.8 ± 6.0 vs. 58.9 ± 4.9 g protein/750 min; P = 0.0001), without effects of distribution on NB. The greater NB was due to the higher PS with 2RDA vs. 1RDA (15.4 ± 4.8 vs. -18.0 ± 8.4 g protein/750 min; P = 0.0018). Consistent with PS, MPS was greater with 2RDA vs. 1RDA, regardless of distribution patterns. In conclusion, whole body net protein balance was greater with protein intake above recommended dietary allowance (0.8 g protein·kg(-1)·day(-1)) in the context of mixed meals, without demonstrated effects of protein intake pattern, primarily through higher rates of protein synthesis at whole body and muscle levels. Copyright © 2015 the American Physiological Society.

  9. Immediate and delayed effects of gill-net capture on acid-base balance and intramuscular lactate concentration of gummy sharks, Mustelus antarcticus.

    Science.gov (United States)

    Frick, Lorenz H; Walker, Terence I; Reina, Richard D

    2012-06-01

    Many sharks are captured as untargeted by-catch during commercial fishing operations and are subsequen