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Sample records for energy balance measurements

  1. Energy Balance Measurement: When Something is Not Better than Nothing

    PubMed Central

    Dhurandhar, Nikhil V.; Schoeller, Dale; Brown, Andrew W.; Heymsfield, Steven B.; Thomas, Diana; Sørensen, Thorkild I.A.; Speakman, John R.; Jeansonne, Madeline; Allison, David B.

    2014-01-01

    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. PMID:25394308

  2. Careful Measurements and Energy Balance Closure - The Case of Soil Heat Flux

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An area of persistent concern in micrometeorological measurements is the failure to close the energy balance at surface flux stations. While most attention has focused on corrections associated with the eddy fluxes, none of the energy balance terms are measured without error. The flux plate method i...

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

    NASA Astrophysics Data System (ADS)

    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. Coherent Structure Patterns Affect Energy Balance Closure: Evidence from Virtual Measurements for a Field Campaign

    NASA Astrophysics Data System (ADS)

    Zhang, S.; De Roo, F.; Heinze, R.; Eder, F.; Huq, S.; Schmidt, M.; Kalthoff, N.; Mauder, M.

    2015-12-01

    The energy balance closure problem is a well-known issue of eddy-covariance measurements. However, the underlying mechanisms are still under debate. Recent evidence suggests that organized low-frequency motion contributes significantly to the energy balance residual, because the associated transport cannot be captured by a point measurement. In this study, we carry out virtual measurements using a PArallelized Large-Eddy Simulation Model (PALM). In order to represent specific measurement days of the field campaign "High definition clouds and precipitation for advancing climate prediction" (HD(CP)²), which was part of the project "High Definition Clouds and Precipitation for Advancing Climate Prediction"(HOPE) in 2013, the simulations were driven by synoptic-scale COSMO-DE reanalysis data. Planet boundary layer height, the vertical profiles of variance and skewness of vertical wind were analyzed and a comparison with Doppler-lidar observations shows good agreement. Furthermore, simulated energy imbalances were compared with real-world imbalances from two eddy-covariance stations in the model domain. Particularly poor energy balance closure was found for a day with cellular organized structures in the surface layer, while the energy balance closure was better on other days with roll-like structures. This finding might be one explanation why the energy balance closure generally tends to improve with increasing friction velocity, since roll-like structures are typically associated with higher wind speeds. In order to gain insight into the partitioning of the energy balance residual between the sensible and latent heat fluxes, we further employed a control volume method within the numerical simulation. Hence, advection and storage terms were identified as the most important causes for the lack of energy balance closure by the eddy-covariance method. The results of the virtual measurements indicate that the "missing" part of the surface energy mainly comes from the

  5. Energy Balance and Obesity

    PubMed Central

    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

  6. CUES - A Study Site for Measuring Snowpack Energy Balance in the Sierra Nevada

    NASA Astrophysics Data System (ADS)

    Bair, Edward; Dozier, Jeff; Davis, Robert; Colee, Michael; Claffey, Keran

    2015-09-01

    Accurate measurement and modeling of the snowpack energy balance are critical to understanding the terrestrial water cycle. Most of the water resources in the western US come from snowmelt, yet statistical runoff models that rely on the historical record are becoming less reliable because of a changing climate. For physically based snow melt models that do not depend on past conditions, ground based measurements of the energy balance components are imperative for verification. For this purpose, the US Army Corps of Engineers Cold Regions Research and Engineering Laboratory (CRREL) and the University of California, Santa Barbara (UCSB) established the “CUES” snow study site (CRREL/UCSB Energy Site, http://www.snow.ucsb.edu/) at 2940 m elevation on Mammoth Mountain, California. We describe CUES, provide an overview of research, share our experience with scientific measurements, and encourage future collaborative research. Snow measurements began near the current CUES site for ski area operations in 1969. In the 1970s, researchers began taking scientific measurements. Today, CUES benefits from year round gondola access and a fiber optic internet connection. Data loggers and computers automatically record and store over 100 measurements from more than 50 instruments each minute. CUES is one of only five high altitude mountain sites in the Western US where a full suite of energy balance components are measured. In addition to measuring snow on the ground at multiple locations, extensive radiometric and meteorological measurements are recorded. Some of the more novel measurements include scans by an automated terrestrial LiDAR, passive and active microwave imaging of snow stratigraphy, microscopic imaging of snow grains, snowflake imaging with a multi-angle camera, fluxes from upward and downward looking radiometers, snow water equivalent from different types of snow pillows, snowmelt from lysimeters, and concentration of impurities in the snowpack. We give an

  7. A Novel Ultrasonic Method for Liquid Level Measurement Based on the Balance of Echo Energy.

    PubMed

    Zhang, Bin; Wei, Yue-Juan; Liu, Wen-Yi; Zhang, Yan-Jun; Yao, Zong; Zhang, Liang; Xiong, Ji-Jun

    2017-03-28

    This study presents a novel method for determining the liquid level from the outside of a sealed container, which is based on the balance of echo energy received by two receiving sensors. The proposed method uses one transmitting transducer and two receiving sensors that are encapsulated in a coupling plane and arranged by certain rules. The calculation and comparison of echo energy are grounded on the difference ultrasonic impedance between gas and liquid media. First, by analyzing the propagation and attenuation characteristics of ultrasonic waves in a solid, an acoustic model for calculating the echo energy is established and simulated in MATLAB. Second, the proposed method is evaluated through a series of experiments. The difference and ratio of echo energy received by two receiving sensors are calculated and compared under two different coupling conditions. Two kinds of the sensors that are arranged by different rules are selected for measuring the liquid level, and the measurement are analyzed and discussed in detail. Finally, the experimental results indicate that the proposed method can meet the proposed accuracy requirements and can effectively solve the problems caused by some poor coupling conditions.

  8. Regulation of Energy Balance.

    ERIC Educational Resources Information Center

    Bray, George A.

    1985-01-01

    Explains relationships between energy intake and expenditure focusing on the cellular, chemical and neural mechanisms involved in regulation of energy balance. Information is referenced specifically to conditions of obesity. (Physicians may earn continuing education credit by completing an appended test). (ML)

  9. Discrepancies between eddy covariance and lysimeter measurements in the assessment of energy balance modeling in vineyards

    NASA Astrophysics Data System (ADS)

    Sánchez, Juan M.; López-Urrea, Ramón; Doña, Carolina; Montoro, Amelia; Caselles, Vicente; Galve, Joan M.

    2016-10-01

    Remote sensing-based models are a potential technique when evapotranspiration (ET) estimates are needed on a regional scale. These remote sensing methods are typically validated and calibrated using in situ measurements. Eddy covariance (EC) and lysimetry are two of the most prevalent techniques for measuring ET. Some discrepancies arise between these two techniques consequence of the measurement footprint or the spatial variability in atmospheric and surface conditions. An experiment was carried out in the growing season of 2015 in a 4 ha row-crop vineyard in a semi-arid advective location in Central Spain, encouraged by the necessity to assess the feasibility of EC measurements in this area and under these conditions. A 9-m2 monolithic weighting lysimeter was available. An EC system was deployed together with a net radiometer and a set of soil heat flux plates. Data of the different terms of the energy balance equation were stored every 15 min, and then averaged at an hourly and daily scales. In this work we focus on the comparison between ET measurements from the two methods, EC and lysimetry. The imbalance in the surface energy budget was first analyzed. A lack of closure around 20% was observed. After forcing the closure, discrepancies between EC and lysimeter measurements still remained. Average estimation errors of +/-0.09 mm h-1 and +/-0.5 mm d-1 were obtained at hourly and daily scales, respectively, whereas a deviation of only 2% was observed in the accumulated ET for the entire experiment. These results support the use of adjusted EC technique to monitor accurate ET in vineyards.

  10. Surface Energy Balance Measurements Above an Exurban Residential Neighbourhood of Kansas City, Missouri

    NASA Astrophysics Data System (ADS)

    Balogun, Ahmed A.; Adegoke, Jimmy O.; Vezhapparambu, Sajith; Mauder, Matthias; McFadden, Joseph P.; Gallo, Kevin

    2009-12-01

    Previous measurements of urban energy balances generally have been limited to densely built, central city sites and older suburban locations with mature tree canopies that are higher than the height of the buildings. In contrast, few data are available for the extensive, open vegetated types typical of low-density residential areas that have been newly converted from rural land use. We made direct measurements of surface energy fluxes using the eddy-covariance technique at Greenwood, a recently developed exurban neighbourhood near Kansas City, Missouri, USA, during an intensive field campaign in August 2004. Energy partitioning was dominated by the latent heat flux under both cloudy and near clear-sky conditions. The mean daytime Bowen ratio ( β) values were 0.46, 0.48, and 0.47 respectively for the cloudy, near clear-sky and all-sky conditions. Net radiation ( R n ) increased rapidly from dawn (-34 and -58W m-2) during the night to reach a maximum (423 and 630W m-2) after midday for cloudy and near clear-sky conditions respectively. Mean daytime values were 253 and 370W m-2, respectively for the cloudy and near clear-sky conditions, while mean daily values were 114 for cloudy and 171W m-2 for near clear-sky conditions, respectively. Midday surface albedo values were 0.25 and 0.24 for the cloudy and near clear-sky conditions, respectively. The site exhibited an angular dependence on the solar elevation angle, in contrast to previous observations over urban and suburban areas, but similar to vegetated surfaces. The latent heat flux ( Q E ), sensible heat flux ( Q H ), and the residual heat storage Δ Q s terms accounted for between 46-58%, 21-23%, and 18-31% of R n , respectively, for all-sky conditions and time averages. The observed albedo, R n , and Q E values are higher than the values that have been reported for suburban areas with high summer evapotranspiration rates in North America. These results suggest that the rapidly growing residential areas at the

  11. Surface energy balance and turbulence measurements on Warszawa Icefield, King George Island, West Antarctica

    NASA Astrophysics Data System (ADS)

    Falk, U.; Sala, H.; Braun, M.

    2012-12-01

    The Antarctic Peninsula is amongst the fastest warming places on Earth and further temperature increase is to be expected. It has undergone rapid environmental changes in the past decades. Exceptional rates of surface air temperature increases (2.5K in 50 years) are concurrent with retreating glacier fronts, an increase in melt areas, surface lowering and rapid retreat of glaciers, break-up and disintegration of ice shelves. The South Shetland Islands are located on the northern tip of the Antarctic Peninsula and are especially vulnerable to climate change due to their maritime climate. For King George Island we have compiled a unique data set comprising direct measurements of evaporation and sensible heat flux by eddy covariance on the Warszawa Icefield over 1.5 years from November 2010 to 2012 in combination with a fully equipped automated weather station measuring long- and short-wave radiation components, profiles of temperature, humidity and wind velocities as well as glacier ice temperatures. The combination with the eddy covariance data allows for analysis of variability and seasonality of surface energy balance components on a glacier for one and a half years. Repeat measurements of snow accumulation and surface lowering along transects on the glacier and at different locations on King George Island are used for analysis of multi-sensor satellite data to identify melt patterns and bare ice areas during summer within the source area of the ground measurements. In combination with long-term time series of weather data, these data give indication of the sensitivity of the ice cap to the ongoing changes. This research is part of the ESF project IMCOAST funded by BMBF. Field work was carried out at the Dallmann laboratory (Carlini station, King George Island/Isla 25 de Mayo) in cooperation of the Instituto Antartico Argentino (Argentina) and the Alfred-Wegener Institute of Marine and Polar Research (Germany).

  12. Field Evaluation of Polymer Capacitive Humidity Sensors for Bowen Ratio Energy Balance Flux Measurements

    PubMed Central

    Savage, Michael J.

    2010-01-01

    The possibility of reliable, reasonably accurate and relatively inexpensive estimates of sensible heat and latent energy fluxes was investigated using a commercial combination thin-film polymer capacitive relative humidity and adjacent temperature sensor instrument. Long-term and unattended water vapour pressure profile difference measurements using low-power combination instruments were compared with those from a cooled dewpoint mirror hygrometer, the latter often used with Bowen ratio energy balance (BREB) systems. An error analysis, based on instrument relative humidity and temperature errors, was applied for various capacitive humidity instrument models. The main disadvantage of a combination capacitive humidity instrument is that two measurements, relative humidity and temperature, are required for estimation of water vapour pressure as opposed to one for a dewpoint hygrometer. In a laboratory experiment using an automated procedure, water vapour pressure differences generated using a reference dewpoint generator were measured using a commercial model (Dew-10) dewpoint hygrometer and a combination capacitive humidity instrument. The laboratory measurement comparisons showed that, potentially, an inexpensive model combination capacitive humidity instrument (CS500 or HMP50), or for improved results a slightly more expensive model (HMP35C or HMP45C), could substitute for the more expensive dewpoint hygrometer. In a field study, in a mesic grassland, the water vapour pressure measurement noise for the combination capacitive humidity instruments was greater than that for the dewpoint hygrometer. The average water vapour pressure profile difference measured using a HMP45C was highly correlated with that from a dewpoint hygrometer with a slope less than unity. Water vapour pressure measurements using the capacitive humidity instruments were not as accurate, compared to those obtained using a dewpoint hygrometer, but the resolution magnitudes for the profile

  13. Long-term energy flux measurements and energy balance over a small boreal lake using eddy covariance technique

    NASA Astrophysics Data System (ADS)

    Nordbo, Annika; Launiainen, Samuli; Mammarella, Ivan; LeppäRanta, Matti; Huotari, Jussi; Ojala, Anne; Vesala, Timo

    2011-01-01

    Measurements of the energy balance components of a small boreal lake (area 0.041 km2, mean depth 2.5 m) in southern Finland were performed during four open water periods (April-October) in 2005-2008. Turbulent fluxes of sensible and latent heat acquired using the eddy covariance technique were accompanied by net radiation and water heat storage measurements. In April the lake was near isothermal, whereas in May the development of a thermocline was enabled by dark water color and a sheltered location. The thermocline continued to deepen until September down to the depth of 3.5 m and prevented the deeper water from interacting with the atmosphere. The sensible heat flux was governed by the air-water temperature difference and had its minimum in the afternoon (values down to -45 W m-2) and peaked in the early morning (values up to 32 W m-2). The monthly means ranged from -9 W m-2 (April 2005) to 24 W m-2 (July 2008). The diurnal variation of the latent heat flux, controlled by vapor pressure deficit, had an opposite diurnal phase with a maximum in the afternoon (values up to 120 W m-2) and minimum in the morning (values down to ˜2 W m-2). The monthly averages ranged from 4 W m-2 (October 2008) to 77 W m-2 (July 2006). Furthermore, the lake acted as a heat sink until July and August when the maximum heat content was about 230 MJ m-2. The monthly energy balance closure varied from 57% to 112%, and the average closure was 82% (residual 16 W m-2) and 72% (residual 23 W m-2) for 2006 and 2007, respectively.

  14. Surface energy balance measurements and modeling on the ice cap of King George Island, West Antarctica

    NASA Astrophysics Data System (ADS)

    Falk, U.; Braun, M.; Sala, H.; Menz, G.

    2012-04-01

    The Antarctic Peninsula is amongst the fastest warming places on Earth and further temperature increase is to be expected. It has undergone rapid environmental changes in the past decades. Exceptional rates of surface air temperature increases (2.5K in 50 years) are concurrent with retreating glacier fronts, an increase in melt areas, surface lowering and rapid retreat, break-up and disintegration of ice shelves. The South Shetland Islands are located on the northern tip of the Peninsula and are especially vulnerable to climate change due to their maritime climate. For King George Island we have compiled a unique data set comprising direct measurements of evaporation and sensible heat flux by eddy covariance on the Warszawa Icefield for the austral summers November 2010 to March 2011 and January to February 2012 in combination with a fully equipped automated weather station measuring long- and short-wave radiation components, profiles of temperature, humidity and wind velocities as well as glacier ice temperatures in profile. The combination with the eddy covariance data allows for analysis of variability and seasonality of surface energy balance components on a glacier for an entire year. Repeat measurements of surface lowering at different locations on King George Island are used for analysis of multi-sensor satellite data to identify melt patterns and bare ice areas during summer. In combination with long-term time series of weather data, these data give indication of the sensitivity of the inland ice cap to the ongoing changes. This research is part of the ESF project IMCOAST funded by BMBF. Field work was carried out at the Dallmann laboratory (Jubany, King George Island) in cooperation of the Instituto Antartico Argentino (Argentina) and the Alfred-Wegener Institute (German).

  15. Surface energy balance measurements over a banana plantation in South China

    NASA Astrophysics Data System (ADS)

    Ding, Zhangwei; Wen, Zhiping; Wu, Renguang; Li, Zhenchao; Zhu, Jianjun; Li, Weibiao; Jian, Maoqiu

    2013-10-01

    The land surface energy exchange depends highly on the surface properties. Little is known of the energy balance over a typical banana plantation of humid tropics. In this study, we examine the characteristics of surface energy exchange over a typical banana field in South China during the period of May 2010 to April 2011 by using the eddy covariance and micrometeorological tower. The results showed that the diurnal and seasonal variations in surface latent heat flux were larger compared with those over the nearby grassland. The dominant energy partitioning varies with season. The latent heat flux was the main consumer of net radiation in summer, whereas the sensible heat flux was the main consumer in winter. The increasing cloud coverage and rain appear to control the surface energy balance with the development of the monsoon. Due to increased afternoon convective cloud systems in the monsoon active period, downward shortwave radiation was dramatically diminished around 14:00 pm. The annual mean Bowen ratio was 0.69, which fell within the range of other vegetated surfaces. The observed surface energy components were not closed, and the ratio of turbulent fluxes to the available energy was about 77 % in October-January and about 85 % in the other months after considering soil heat and air heat storage.

  16. Energy balance in peridynamics.

    SciTech Connect

    Lehoucq, Richard B.; Silling, Stewart Andrew

    2010-09-01

    The peridynamic model of solid mechanics treats internal forces within a continuum through interactions across finite distances. These forces are determined through a constitutive model that, in the case of an elastic material, permits the strain energy density at a point to depend on the collective deformation of all the material within some finite distance of it. The forces between points are evaluated from the Frechet derivative of this strain energy density with respect to the deformation map. The resulting equation of motion is an integro-differential equation written in terms of these interparticle forces, rather than the traditional stress tensor field. Recent work on peridynamics has elucidated the energy balance in the presence of these long-range forces. We have derived the appropriate analogue of stress power, called absorbed power, that leads to a satisfactory definition of internal energy. This internal energy is additive, allowing us to meaningfully define an internal energy density field in the body. An expression for the local first law of thermodynamics within peridynamics combines this mechanical component, the absorbed power, with heat transport. The global statement of the energy balance over a subregion can be expressed in a form in which the mechanical and thermal terms contain only interactions between the interior of the subregion and the exterior, in a form anticipated by Noll in 1955. The local form of this first law within peridynamics, coupled with the second law as expressed in the Clausius-Duhem inequality, is amenable to the Coleman-Noll procedure for deriving restrictions on the constitutive model for thermomechanical response. Using an idea suggested by Fried in the context of systems of discrete particles, this procedure leads to a dissipation inequality for peridynamics that has a surprising form. It also leads to a thermodynamically consistent way to treat damage within the theory, shedding light on how damage, including the

  17. Eddy Covariance Measurements Over a Maize Field: The Contribution of Minor Flux Terms to the Energy Balance Gap

    NASA Astrophysics Data System (ADS)

    Smidt, J.; Ingwersen, J.; Streck, T.

    2015-12-01

    The lack of energy balance closure is a long-standing problem in eddy covariance (EC) measurements. The energy balance equation is defined as Rn - G = H + λE, where Rn is net radiation, G is the ground heat flux, H is the sensible heat flux and λE is the latent heat flux. In most cases of energy imbalance, either Rn is overestimated or the ground heat and turbulent fluxes are underestimated. Multiple studies have shown that calculations, incorrect instrument installation/calibration and measurement errors alone do not entirely account for this imbalance. Rather, research is now focused on previously neglected sources of heat storage in the soil, biomass and air beneath the EC station. This project examined the potential of five "minor flux terms" - soil heat storage, biomass heat storage, energy consumption by photosynthesis, air heat storage and atmospheric moisture change, to further close the energy balance gap. Eddy covariance measurements were conducted at a maize (Zea mays) field in southwest Germany during summer 2014. Soil heat storage was measured for six weeks at 11 sites around the field footprint. Biomass and air heat storage were measured for six subsequent weeks at seven sites around the field footprint. Energy consumption by photosynthesis was calculated using the CO2 flux data. Evapotranspiration was calculated using the water balance method and then compared to the flux data processed with three post-closure methods: the sensible heat flux, the latent heat flux and the Bowen ratio post-closure methods. An energy balance closure of 66% was achieved by the EC station measurements over the entire investigation period. During the soil heat flux campaign, EC station closure was 74.1%, and the field footprint soil heat storage contributed 3.3% additional closure. During the second minor flux term measurement period, closure with the EC station data was 91%. Biomass heat storage resulted in 1.1% additional closure, the photosynthesis flux closed the gap

  18. Energy balance measurements over a small reservoir in Ghana's Upper East Region

    NASA Astrophysics Data System (ADS)

    van de Giesen, Nick; Ohene Annor, Frank

    2013-04-01

    Near the small village of Binaba (10.778927 deg N, 0.464859 deg E), a small irrigation reservoir has been instrumented to measure different parts of the energy balance of this water body. Instruments were placed on, or attached to, a spar platform. This platform consisted of a long PVC pipe, the spar, which is closed at the bottom. On the PVC pipe rests an aluminum frame platform that carries instrumentation and solar power panel. In turn, the platform rests partially on a large inflated tire. At the bottom of the PVC pipe, lead weights and batteries were placed to ensure a very low point of gravity to minimize wave impact on the platform movement. The tire ensures a large second moment of the water plane. The combination of large second momentum of the water plane and small displacement, ensures a high placement of the metacenter. The distance between the point of gravity and the metacenter is relatively long and the weight is large due to the weights and batteries. This ensures that the eigenfrequency of the platform is very low. On the platform, we fixed a WindMaster Pro (sonic anemometer for 3D wind speed and air temperature to perform eddy covariance measurements of sensible heat flux), a NR Lite (net radiometer), and air temperature and relative humidity sensors. Water temperature at different depths was measured with a string of TidbiT's (waterproof temperature sensors and loggers). The platform had a wind vane and the spar could turn freely around its anchor cable to ensure that the anemometer always faced upwind. A compass in the logger completed this setup. First results suggest, as expected, that the sensible heat flux is relatively small with on average 20 W/m2 over the course of a day. Sensible heat flux peaked around midnight at 35 W/m2, when the warm water warmed up the air from the colder surrounding land. The dynamics of heat storage during the daytime and longwave radiation during the night time, are important to calculate the latent heat flux.

  19. Energy balance climate models

    NASA Technical Reports Server (NTRS)

    North, G. R.; Cahalan, R. F.; Coakley, J. A., Jr.

    1981-01-01

    An introductory survey of the global energy balance climate models is presented with an emphasis on analytical results. A sequence of increasingly complicated models involving ice cap and radiative feedback processes are solved, and the solutions and parameter sensitivities are studied. The model parameterizations are examined critically in light of many current uncertainties. A simple seasonal model is used to study the effects of changes in orbital elements on the temperature field. A linear stability theorem and a complete nonlinear stability analysis for the models are developed. Analytical solutions are also obtained for the linearized models driven by stochastic forcing elements. In this context the relation between natural fluctuation statistics and climate sensitivity is stressed.

  20. Dual-energy approach to contrast-enhanced mammography using the balanced filter method: Spectral optimization and preliminary phantom measurement

    SciTech Connect

    Saito, Masatoshi

    2007-11-15

    Dual-energy contrast agent-enhanced mammography is a technique of demonstrating breast cancers obscured by a cluttered background resulting from the contrast between soft tissues in the breast. The technique has usually been implemented by exploiting two exposures to different x-ray tube voltages. In this article, another dual-energy approach using the balanced filter method without switching the tube voltages is described. For the spectral optimization of dual-energy mammography using the balanced filters, we applied a theoretical framework reported by Lemacks et al. [Med. Phys. 29, 1739-1751 (2002)] to calculate the signal-to-noise ratio (SNR) in an iodinated contrast agent subtraction image. This permits the selection of beam parameters such as tube voltage and balanced filter material, and the optimization of the latter's thickness with respect to some critical quantity--in this case, mean glandular dose. For an imaging system with a 0.1 mm thick CsI:Tl scintillator, we predict that the optimal tube voltage would be 45 kVp for a tungsten anode using zirconium, iodine, and neodymium balanced filters. A mean glandular dose of 1.0 mGy is required to obtain an SNR of 5 in order to detect 1.0 mg/cm{sup 2} iodine in the resulting clutter-free image of a 5 cm thick breast composed of 50% adipose and 50% glandular tissue. In addition to spectral optimization, we carried out phantom measurements to demonstrate the present dual-energy approach for obtaining a clutter-free image, which preferentially shows iodine, of a breast phantom comprising three major components - acrylic spheres, olive oil, and an iodinated contrast agent. The detection of iodine details on the cluttered background originating from the contrast between acrylic spheres and olive oil is analogous to the task of distinguishing contrast agents in a mixture of glandular and adipose tissues.

  1. Estimation of Actual Crop ET of Paddy Using the Energy Balance Model SMARET and Validation with Field Water Balance Measurements and a Crop Growth Model (ORYZA)

    NASA Astrophysics Data System (ADS)

    Nallasamy, N. D.; Muraleedharan, B. V.; Kathirvel, K.; Narasimhan, B.

    2014-12-01

    Sustainable management of water resources requires reliable estimates of actual evapotranspiration (ET) at fine spatial and temporal resolution. This is significant in the case of rice based irrigation systems, one of the major consumers of surface water resources and where ET forms a major component of water consumption. However huge tradeoff in the spatial and temporal resolution of satellite images coupled with lack of adequate number of cloud free images within a growing season act as major constraints in deriving ET at fine spatial and temporal resolution using remote sensing based energy balance models. The scale at which ET is determined is decided by the spatial and temporal scale of Land Surface Temperature (LST) and Normalized Difference Vegetation Index (NDVI), which form inputs to energy balance models. In this context, the current study employed disaggregation algorithms (NL-DisTrad and DisNDVI) to generate time series of LST and NDVI images at fine resolution. The disaggregation algorithms aimed at generating LST and NDVI at finer scale by integrating temporal information from concurrent coarse resolution data and spatial information from a single fine resolution image. The temporal frequency of the disaggregated images is further improved by employing composite images of NDVI and LST in the spatio-temporal disaggregation method. The study further employed half-hourly incoming surface insolation and outgoing long wave radiation obtained from the Indian geostationary satellite (Kalpana-1) to convert the instantaneous ET into daily ET and subsequently to the seasonal ET, thereby improving the accuracy of ET estimates. The estimates of ET were validated with field based water balance measurements carried out in Gadana, a subbasin predominated by rice paddy fields, located in Tamil Nadu, India.

  2. Energy balance of wheat conversion to ethanol

    SciTech Connect

    Stumborg, M.A.; Zentner, R.P.; Coxworth, E.

    1996-12-31

    The Western Canadian ethanol industry uses wheat as the preferred feed stock. The net energy balance of an ethanol system based on this starchy feed stock is of interest if Canada utilizes ethanol fuels from wheat as one of its measures to meet international commitments for greenhouse gas reduction and energy conservation under the Green Plan. The wheat to ethanol production systems for the Brown and Thin Black soil zones of the Canadian Prairies were analyzed from soil to processing completion to determine the net energy balance. The data clearly demonstrates the positive net energy balance, with the energy balance ranging from 1.32 to 1.63:1 for the Brown soil zone, and from 1.19 to 1.47:1 for the Thin Black soil zone. The final energy balance depends upon the agronomic practices and wheat variety assumed for the production system.

  3. Surface energy balance measurements at a tropical site in West Africa during the transition from dry to wet season

    NASA Astrophysics Data System (ADS)

    Mauder, M.; Jegede, O. O.; Okogbue, E. C.; Wimmer, F.; Foken, T.

    2007-07-01

    In one of the first micrometeorological experiments at a tropical site in West Africa, direct measurements of all surface energy balance components were carried out. The experiment NIMEX-1 in Ile-Ife, Nigeria (7°33' N, 4°33' E), was conducted from February 19, 2004 to March 9, 2004, during the transition from the dry to the wet season. Three typical weather situations could be observed: firstly, monsoonal winds from the southwest blew over desiccated soils. Almost 100% of the available energy at the surface was transformed into sensible heat flux. Secondly, after several thundershowers, monsoonal winds swept over soils of increased water content, which led to a partitioning of the available energy corresponding to Bowen ratios between 0.3 and 0.5. Thirdly, harmattan winds advected dry dusty air from northern directions, which reduced the incoming shortwave radiation. Again, Bowen ratios range from 0.3 to 0.5 during daytime, whereas latent heat fluxes are still high during the night due to the advection of very dry air. No systematic non-closure of the surface energy balance could be found for the NIMEX-1 dataset. Unlike other experiments in Europe, most of the ogives for the sensible and latent heat flux were found to be convergent during NIMEX-1 in Ile-Ife. This can be attributed to the homogeneity of the surrounding bush, which lacks the defined borders found in agriculturally cultivated landscapes.

  4. Surface Energy Balance: Lessons Learned from Modeling Simulations and Field Measurements at an Oak-grass Savanna in California

    NASA Astrophysics Data System (ADS)

    Ma, S.; Baldocchi, D. D.; Vila-Guerau Arellano, J.; Osuna, J. L.; Wharton, S.

    2013-12-01

    The eddy-covariance method has been applied successfully in investigating CO2 fluxes exchanged between atmosphere and ecosystem over a relatively long period of time (e.g., annual or multi-years), but understanding uncertainties associated with the measurements is an ongoing task. While modeling efforts integrate our best knowledge of biophysical processes, model uncertainty is also unavoidable. The question is often asked how well modeling simulations can agree with field measurements. In this study, we intended to learn lessons from uncertainties of both approaches. We compare results of a meteorological, process-based model, Chemistry Land-surface Atmosphere Soil Slab (CLASS) model, with our field measurements at an oak-grass savanna ecosystem (Tonzi Ranch, Ione, California). The CLASS model, based on the mixed-layer theory coupled to a dynamic vegetation and soil model, reproduces the surface energy balance, surface carbon dioxide processes and boundary layer dynamics. We systematically study different days in 2012, including a wet spring day (Apr. 19), a dry summer day (Sep. 26), and an autumn day immediately following a rain event (Oct. 26). The model-simulated net radiation agrees well with direct measurements in the field. The boundary layer height predicted by the model agrees with estimates radiosonde profile measurements. The model predicts lower sensible and latent heat fluxes than tower-derived values. Although the eddy-covariance method likely underestimates these two energy terms due to loss of high- or low-frequency turbulence, the amount of heat stored in the surface litter layer and tree canopy could also be significant for this type of ecosystem. Because the model has not included these heat storage terms or modified key parameters specifically for this type of ecosystem, results of the model provide a starting point to understand uncertainties in the field measurements. Effects of drought and rain events on surface energy balance will also be

  5. Evaluation of the Town Energy Balance (TEB) Scheme with Direct Measurements from Dry Districts in Two Cities.

    NASA Astrophysics Data System (ADS)

    Masson, V.; Grimmond, C. S. B.; Oke, T. R.

    2002-10-01

    The Town Energy Balance (TEB) model of Masson simulates turbulent fluxes for urban areas. It is forced with atmospheric data and radiation recorded above roof level and incorporates detailed representations of the urban surface (canyon geometry) to simulate energy balances for walls, roads, and roofs. Here the authors evaluate TEB using directly measured surface temperatures and local-scale energy balance and radiation fluxes for two `simple' urban sites: a downtown area within the historic core of Mexico City, Mexico (stone buildings five to six stories in height), and a light industrial site in Vancouver, British Columbia, Canada (flat-roofed, single-story warehouses). At both sites, vegetation cover is less than 5%, which permits direct evaluation of TEB in the absence of a coupled vegetation scheme. Following small modifications to TEB, notably to the aerodynamic resistance formulations, the model is shown to perform well overall. In Mexico City, with deep urban canyons and stone walls, almost two-thirds of the net radiation is partitioned into storage heat flux during the day, and this maintains large heat releases and an upward turbulent sensible heat flux at night. TEB simulates all of these features well. At both sites TEB correctly simulates the net radiation, surface temperatures, and the partitioning between the turbulent and storage heat fluxes. The composite wall temperature simulated by TEB is close to the average of the four measured wall temperatures. A sensitivity analysis of model parameters shows TEB is fairly robust; for the conditions considered here, TEB is most sensitive to roof characteristics and incoming solar radiation.

  6. Surface Energy Balance System (SEBS) Handbook

    SciTech Connect

    Cook, DR

    2011-02-14

    A Surface Energy Balance System (SEBS) has been installed collocated with each deployed ECOR system at the Southern Great Plains (SGP), North Slope of Alaska (NSA), Tropical Western Pacific (TWP), ARM Mobile Facility 1 (AMF1), and ARM Mobile Facility 2 (AMF2). The surface energy balance system 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.

  7. Performance measurements and energy balance of an SPS V160 Stirling motor at the German Aerospace Research Establishment

    NASA Astrophysics Data System (ADS)

    Noyes, Gerold

    1990-02-01

    Before conversion to solar operation to serve as a solar receiver test bed, a Stirling Power Systems (SPS) V160F natural gas-fired co-generation stirling motor was tested. A test stand was built and instrumented, and the motor performance was measured under various loads. An energy balance of the motor/generator unit was done including electric output and input, thermal input, waste heat in the cooling water, cooling air, exhaust, radiation and free convection from the motor housing. The influence of the internal cooling water temperature on motor performance was measured. Measurements, including an exhaust gas analysis and surface temperature distribution, were made to determine the combustion chamber efficiency. A magnetic eddy current brake was used to measure the shaft output of the stirling motor and measure the efficiency of the generator. The total natural gas to electric energy conversion efficiency was measured to be 23 percent above 2/3 of full power; 20 percent efficiency was achieved down to 1/3 power. Maximum power was measured at 8.9 kWc.

  8. Textile protection of snow and ice: Measured and simulated effects on the energy- and mass balance

    NASA Astrophysics Data System (ADS)

    Olefs, Marc; Lehning, Michael

    2010-05-01

    Measurements and simulations of the energy fluxes and mass changes of an artificially covered snow and ice surface (geotextile material) and a reference plot within an Austrian glacier ski resort are presented and compared. A modified version of the snow cover model SNOWPACK is used to successfully reproduce the artificially compacted and the additionally covered snow cover in a physically based way. Supplementary measurements of crucial material properties of the 0.0045 m thin geotextile serve as model input as well. Results indicate that the shortwave reflectivity of the covers is responsible for half the performance (47%). Thermal insulation of the material (14%) and a negative latent heat flux due to evaporation of precipitation from the cover surface (10%) have almost the same contribution. An assumed layer of air between the cover and the snow and ice surface (thickness 0.075 m to 0.12 m) adds the rest, which is at the upper limit of observations and may therefore also compensate for model errors. This generally explains the high performance of the method in glacier skiing resorts and, most importantly, an altitude dependant application limit of the method: the method becomes less effective at lower altitudes, where sensible heat fluxes become more important compared to short wave radiation.

  9. Spectral optimization for measuring electron density by the dual-energy computed tomography coupled with balanced filter method.

    PubMed

    Saito, Masatoshi

    2009-08-01

    Dual-energy computed tomography (DECT) has the potential for measuring electron density distribution in a human body to predict the range of particle beams for treatment planning in proton or heavy-ion radiotherapy. However, thus far, a practical dual-energy method that can be used to precisely determine electron density for treatment planning in particle radiotherapy has not been developed. In this article, another DECT technique involving a balanced filter method using a conventional x-ray tube is described. For the spectral optimization of DECT using balanced filters, the author calculates beam-hardening error and air kerma required to achieve a desired noise level in electron density and effective atomic number images of a cylindrical water phantom with 50 cm diameter. The calculation enables the selection of beam parameters such as tube voltage, balanced filter material, and its thickness. The optimized parameters were applied to cases with different phantom diameters ranging from 5 to 50 cm for the calculations. The author predicts that the optimal combination of tube voltages would be 80 and 140 kV with Tb/Hf and Bi/Mo filter pairs for the 50-cm-diameter water phantom. When a single phantom calibration at a diameter of 25 cm was employed to cover all phantom sizes, maximum absolute beam-hardening errors were 0.3% and 0.03% for electron density and effective atomic number, respectively, over a range of diameters of the water phantom. The beam-hardening errors were 1/10 or less as compared to those obtained by conventional DECT, although the dose was twice that of the conventional DECT case. From the viewpoint of beam hardening and the tube-loading efficiency, the present DECT using balanced filters would be significantly more effective in measuring the electron density than the conventional DECT. Nevertheless, further developments of low-exposure imaging technology should be necessary as well as x-ray tubes with higher outputs to apply DECT coupled with the

  10. Is scintillometer measurement accurate enough for evaluating remote sensing based energy balance ET models?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The three evapotranspiration (ET) measurement/retrieval techniques used in this study, lysimeter, scintillometer and remote sensing vary in their level of complexity, accuracy, resolution and applicability. The lysimeter with its point measurement is the most accurate and direct method to measure ET...

  11. Balancing the Energy Pendulum.

    ERIC Educational Resources Information Center

    MacKinnon, Sharon

    1987-01-01

    The city of Kitchener, Ontario, has installed a heat recovery loop in one indoor pool, all indoor swimming pools use pool covers, and two have solar heating. Energy is saved in two ice arenas by low-emissivity ceilings, and in the largest arena by a heat recovery system. (MLF)

  12. Application of detailed temperature profile measurements for improving data quality check by Bowen Ratio/Energy Balance method

    NASA Astrophysics Data System (ADS)

    Pozníková, Gabriela; Fischer, Milan; Orság, Matěj; Trnka, Miroslav; Žalud, Zdeněk

    2015-04-01

    Water plays a key role in the functionality and sustainability of the ecosystems. In the light of the predicted climate change research should be focused on the water cycle and its individual components. Apart from the runoff, the major component of the water balance which drives the water from the ecosystems is represented by the evapotranspiration (ET). One of the standard methods for measuring ET is Bowen Ratio/Energy Balance method (BREB). It is based on the assumption that the water vapour and heat are transported by identical eddies with equal efficiency. In fact, this basic premise is based on a more complicated Monin-Obukhov similarity theory that explains the relationship between the profiles of wind, temperature and water vapour in the surface layer of the atmosphere. When BREB method is used we assume that the profiles of temperature and air humidity are ideally logarithmic or at least consistent. However, as this method is usually based on the measurements of temperature and humidity in only two heights, it is difficult to verify this assumption. We therefore conducted a field experiment using 4m high measurement-mast with 20 thermocouples connected to data-logger for detailed measurement of air temperature profile above different covers, e.g. grassland, spring barley, poplar plantation. The main goal of our effort was to capture so called "kink" in the profile of the temperature and verify if the assumptions made by BREB hold under various weather conditions and over different canopies testing the basic requirements of the BREB method use. Finally we devised a technique improving data selection for subsequent ET calculation. This study was funded by project "Building up a multidisciplinary scientific team focused on drought" No. CZ.1.07/2.3.00/20.0248,PASED - project supported by Czech program KONTAKT II No. LH12037 "Development of models for assessment of abiotic stresses in selected bioenergy plants" and LD130030 project supporting COST action ES1106.

  13. Measurement of surface energy balance components in dryland wheat/fallow and limited-irrigation corn

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Water evaporation from soil and plant surfaces and plant transpiration comprise land surface/canopy evapotranspiration (ET), which is essential to estimate for land-atmosphere interaction and crop water use. There are no direct measurements of ET, and the most direct methods (e.g., weighing lysimet...

  14. Evapotranspiration of a pine-switchgrass intercropping bioenergy system measured by combined surface renewal and energy balance method

    NASA Astrophysics Data System (ADS)

    Fischer, M.; Noormets, A.; Domec, J. C.; Rosa, R.; Williamson, J.; Boone, J.; Sucre, E.; Trnka, M.; King, J.

    2015-12-01

    Intercropping bioenergy grasses within traditional pine silvicultural systems provides an opportunity for economic diversification and regional bioenergy production in a way that complements existing land use systems. Bioenergy intercropping in pine plantations does not compete with food production for land and it is thought will increase ecosystem resource-use efficiencies. As the frequency and intensity of drought is expected to increase with the changing climate, maximizing water use-efficiency of intercropped bioenergy systems will become increasingly important for long-term economic and environmental sustainability. The presented study is focused on evapotranspiration (ET) of an experimental pine-switchgrass intercropping system in the Lower Coastal Plain of North Carolina. We measured ET of two pure switchgrass fields, two pure pine stands and two pine-switchgrass intercropping systems using combined surface renewal (SR) and energy balance (EB) method throughout 2015. SR is based on high-frequency measurement of air temperature at or above canopy. As previously demonstrated, temperature time series are associated with identifiable, repeated patterns called "turbulent coherent structures". These coherent structures are considered to be responsible for most of the turbulent transport. Statistical analysis of the coherent structures in temperature time series allows quantification of sensible heat flux density (H) from the investigated area. Information about H can be combined with measurement of net radiation and soil heat flux density to indirectly obtain ET estimates as a residual of the energy balance equation. Despite the recent progress in the SR method, there is no standard methodology and each method available includes assumptions which require more research. To validate our SR estimates of ET, we used an eddy covariance (EC) system placed temporarily next to the each SR station as a comparative measurement of H. The conference contribution will include

  15. The energy balance of the nighttime thermosphere

    NASA Technical Reports Server (NTRS)

    Glenar, D. A.

    1977-01-01

    The discrepancy between the input from the day hemisphere and the observed loss rates is discussed in terms of ion-neutral processes and gravity wave inputs. There has been considerable speculation as to the energy balance of the thermosphere and in particular about the fraction of the total energy input supplied by ultraviolet radiation. The problem is considerably simplified by considering the energy balance of the nighttime hemisphere alone. Sunrise and sunset vapor trail measurements provide data on the wind systems at the terminator boundary, and temperature measurements provide information on the vertical energy conduction. North-south winds from high latitude vapor trail measurements provide a measure of the energy input from auroral processes.

  16. Energy and water balance determination in an advective environment:From direct measurement to microclimate based estimation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The contributions of John Monteith are perhaps nowhere more widely acknowledged than in the community of scientists and engineers concerned with estimation of evapotranspiration. His addition of surface energy balance flux resistance formulations to the evaporation estimation formula of Penman presa...

  17. Surface Energy Balance System (SEBS) Handbook

    SciTech Connect

    Cook, D. R.

    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.

  18. Evaluation of Two Energy Balance Closure Parametrizations

    NASA Astrophysics Data System (ADS)

    Eder, Fabian; De Roo, Frederik; Kohnert, Katrin; Desjardins, Raymond L.; Schmid, Hans Peter; Mauder, Matthias

    2014-05-01

    A general lack of energy balance closure indicates that tower-based eddy-covariance (EC) measurements underestimate turbulent heat fluxes, which calls for robust correction schemes. Two parametrization approaches that can be found in the literature were tested using data from the Canadian Twin Otter research aircraft and from tower-based measurements of the German Terrestrial Environmental Observatories (TERENO) programme. Our analysis shows that the approach of Huang et al. (Boundary-Layer Meteorol 127:273-292, 2008), based on large-eddy simulation, is not applicable to typical near-surface flux measurements because it was developed for heights above the surface layer and over homogeneous terrain. The biggest shortcoming of this parametrization is that the grid resolution of the model was too coarse so that the surface layer, where EC measurements are usually made, is not properly resolved. The empirical approach of Panin and Bernhofer (Izvestiya Atmos Oceanic Phys 44:701-716, 2008) considers landscape-level roughness heterogeneities that induce secondary circulations and at least gives a qualitative estimate of the energy balance closure. However, it does not consider any feature of landscape-scale heterogeneity other than surface roughness, such as surface temperature, surface moisture or topography. The failures of both approaches might indicate that the influence of mesoscale structures is not a sufficient explanation for the energy balance closure problem. However, our analysis of different wind-direction sectors shows that the upwind landscape-scale heterogeneity indeed influences the energy balance closure determined from tower flux data. We also analyzed the aircraft measurements with respect to the partitioning of the "missing energy" between sensible and latent heat fluxes and we could confirm the assumption of scalar similarity only for Bowen ratios 1.

  19. Surface energy balance of an extensive green roof as quantified by full year eddy-covariance measurements.

    PubMed

    Heusinger, Jannik; Weber, Stephan

    2017-01-15

    Green roofs are discussed as a promising type of green infrastructure to lower heat stress in cities. In order to enhance evaporative cooling, green roofs should ideally have similar Bowen ratio (β=sensible heat flux/latent heat flux) characteristics such as rural sites, especially during summer periods with high air temperatures. We use the eddy-covariance (EC) method to quantify the energy balance of an 8600m(2) extensive, non-irrigated green roof at the Berlin Brandenburg Airport, Germany over a full annual cycle. To understand the influence of water availability on green roof-atmosphere energy exchange, we studied dry and wet periods and looked into functional relationships between leaf area, volumetric water content (VWC) of the substrate, shortwave radiation and β. The surface energy balance was dominated by turbulent heat fluxes in comparison to conductive substrate heat fluxes. The Bowen ratio was slightly below unity on average but highly variable due to ambient meteorology and substrate water availability, i.e. β increased to 2 in the summer season. During dry periods mean daytime β was 3, which is comparable to typical values of urban instead of rural sites. In contrast, mean daytime β was 0.3 during wet periods. Following a summer wet period the green roof maximum daily evapotranspiration (ET) was 3.3mm, which is a threefold increase with respect to the mean summer ET. A multiple regression model indicated that the substrate VWC at the present site has to be >0.11m(3)m(-3) during summer high insolation periods (>500Wm(-2)) in order to maintain favourable green roof energy partitioning, i.e. mid-day β<1. The microclimate benefit of urban green roofs can be significantly optimised by using sustainable irrigation approaches.

  20. Energy-balance climate models

    NASA Technical Reports Server (NTRS)

    North, G. R.; Cahalan, R. F.; Coakley, J. A., Jr.

    1980-01-01

    An introductory survey of the global energy balance climate models is presented with an emphasis on analytical results. A sequence of increasingly complicated models involving ice cap and radiative feedback processes are solved and the solutions and parameter sensitivities are studied. The model parameterizations are examined critically in light of many current uncertainties. A simple seasonal model is used to study the effects of changes in orbital elements on the temperature field. A linear stability theorem and a complete nonlinear stability analysis for the models are developed. Analytical solutions are also obtained for the linearized models driven by stochastic forcing elements. In this context the relation between natural fluctuation statistics and climate sensitivity is stressed.

  1. [Energy and mass exchange and the productivity of the main ecosystems of Siberia (from eddy covariance measurements). 1. Heat balance structure in the vegetation season].

    PubMed

    Chebakova, N M; Vygodskaia, N N; Arnet, A; Belelli Markezini, L; Kolle, O; Kurbatova, Iu A; Parfenova, E I; Valentini, R; Vaganov, E A; Shul'tse, E D

    2013-01-01

    Direct measurements of heat balance (turbulent heat transfer and evaporation heat consumption) by the method of turbulent pulsations in 1998-2000 and 2002-2004 were used to obtain information on the daily, seasonal, and annual dynamics of energy fluxes and mass transfer between the atmosphere and the typical ecosystems of Siberia (middle-taiga pine forest and raised bog, true four-grass steppe, with the use of data for typical tundra) along the Yenisei meridian (90 degrees E).

  2. Energy balance and non-turbulent fluxes

    NASA Astrophysics Data System (ADS)

    Moderow, Uta; Feigenwinter, Christian; Bernhofer, Christian

    2010-05-01

    Often, the sum of the turbulent fluxes of sensible heat and latent heat from eddy covariance (EC) measurements does not match the available energy (sum of net radiation, ground heat flux and storage changes). This is referred to as energy balance closure gap. The reported imbalances vary between 0% and 50% (Laubach 1996). In various publications, it has been shown that the uncertainty of the available energy itself does not explain the gap (Vogt et al. 1996; Moderow et al. 2009). Among other reasons, the underestimation is attributed to an underestimation of turbulent fluxes and undetected non-turbulent transport processes, i.e. advection (e.g. Foken et al. 2006). The imbalance is typically larger during nighttime than during daytime as the EC method fails to capture non-turbulent transports that can be significant during night (e.g. Aubinet 2008). Results for the budget of CO2 showed that including non-turbulent fluxes can change the budgets considerably. Hence, it is interesting to see how the budget of energy is changed. Here, the consequences of including advective fluxes of sensible heat and latent heat in the energy balance are explored with focus on nighttime conditions. Non-turbulent fluxes will be inspected critically regarding their plausibility. Following Bernhofer et al. (2003), a ratio similar to Bowen's ratio of the turbulent fluxes are defined for the non-turbulent fluxes and compared to each other. This might have implications for the partitioning of the available energy into sensible heat and latent heat. Data of the ADVEX-campaigns (Feigenwinter et al. 2008) of three different sites across Europe are used and selected periods are inspected. References Aubinet M (2008) Eddy covariance CO2-flux measurements in nocturnal conditions: An analysis of the problem. Ecol Appl 18: 1368-1378 Bernhofer C, Grünwald T, Schwiebus A, Vogt R (2003) Exploring the consequences of non-zero energy balance closure for total surface flux. In: Bernhofer C (ed

  3. Energy balance comparison of sorghum and sunflower

    NASA Astrophysics Data System (ADS)

    Rachidi, F.; Kirkham, M. B.; Kanemasu, E. T.; Stone, L. R.

    1993-03-01

    An understanding of the energy exchange processes at the surface of the earth is necessary for studies of global climate change. If the climate becomes drier, as is predicted for northern mid-latitudes, it is important to know how major agricultural crops will play a role in the budget of heat and moisture. Thus, the energy balance components of sorghum [ Sorghum bicolor (L.) Moench.] and sunflower ( Helianthus annuus L.), two drought-resistant crops grown in the areas where summertime drying is forecasted, were compared. Soil water content and evapotranspiration ( ET) rates also were determined. Net radiation was measured with net radiometers. Soil heat flux was analyzed with heat flux plates and thermocouples. The Bowen ratio method was used to determine sensible and latent heat fluxes. Sunflower had a higher evapotranspiration rate and depleted more water from the soil than sorghum. Soil heat flux into the soil during the daytime was greater for sorghum than sunflower, which was probably the result of the more erect leaves of sorghum. Nocturnal net radiation loss from the sorghum crop was greater than that from the sunflower crop, perhaps because more heat was stored in the soil under the sorghum crop. But daytime net radiation values were similar for the two crops. The data indicated that models of climate change must differentiate nighttime net radiation of agricultural crops. Sensible heat flux was not always less (or greater) for sorghum compared to sunflower. Sunflower had greater daytime values for latent heat flux, reflecting its greater depletion of water from the soil. Evapotranspiration rates determined by the energy balance method agreed relatively well with those found by the water balance method. For example, on 8 July (43 days after planting), the ET rates found by the energy-balance and water-balance methods were 4.6 vs. 5.5 mm/day for sunflower, respectively; for sorghum, these values were 4.0 vs. 3.5 mm/day, respectively. If the climate does

  4. Energy balance during recovery from malnutrition.

    PubMed

    Spady, D W; Payne, P R; Picou, D; Waterlow, J C

    1976-10-01

    This report presents an account of energy balance of young Jamaican children recovering from protein-energy malnutrition (PEM). This was done in three steps. Initially the true gross energy of a formula used in the treatment of PEM was determined by bomb calorimetry. Then its metabolizable energy content was determined in a group of nine children recovering from PEM. In a similar but different group of eight children total daily metabolizable energy intake (EI), average rate of weight gain (g/kg/day) (WG), and total daily energy expenditure (TDEE) were determined. TDEE was determined by indirect calorimetry using a heart rate counter and is based on the relationship of heart rate to oxygen consumption. In this group, the mean EI was 122.5 kcal, WG was 8.4 g, and TDEE was 92 kcal. The difference between EI and TDEE was 30.7 kcal/kg, or 3.3 kcal/g of weight gain. This difference is presumed to be the stored energy in new tissue and corresponds to a proposed new tissue composition of 31% fat and 14% protein. A regression curve comparison of WG versus EI showed that at zero weight gain EI was 85.5 kcal and each additional gain. The difference of 1.0 kcal between total energy cost and stored energy reflects the energy required to deposit new tissue. Gram weight gain required 4.4 kcal. The latter figure is felt to reflect the total energy cost of weight. From three independent measurements, an estimate of maintenance energy requirements was estimated to be about 82 kcal/kg/day.

  5. Alcohol from corn: poor energy balance

    SciTech Connect

    Not Available

    1981-08-10

    It is reported that most processing plants producing alcohol from corn currently operate with very unfavourable energy balances. The energy needed to grow and harvest corn plus petroleum or natural gas used in the processing phase often exceeds the energy that can be derived from the alcohol.

  6. PV modules with optimized energy balance

    NASA Astrophysics Data System (ADS)

    Weixlberger, Johann; Bruckner, Richard

    2011-09-01

    The overall energy balance of a solar PV-module across its life time needs a consideration incl. its energy consumption during manufacturing process versus its energy harvesting capabilities during life time. A glass-glass-module based on thin tempered glass on front and backside can dramatically influence this overall balance, since more than 50 % of encapsulation materials manufacturing energy can be saved, followed by a an further impact on frameless mounting of light-weighted modules, reducing mounting costs and enabling simpler BIPV.

  7. Failure of correct evapotranspiration measurements by eddy covariance under certain conditions and energy balance closure in open-oak savanna ecosystems

    NASA Astrophysics Data System (ADS)

    Pérez-Priego, Oscar; Migliavacca, Mirco; El-Madany, Tarek; Carrara, Arnaud; Moreno, Gerardo; Kolle, Olaf; Reichstein, Markus

    2016-04-01

    Separation of evapotranspiration (ET) into its components represents one of the main ecohydrological challenges in heterogeneous ecosystems (i.e. tree-grass savanna), where two main evaporative layers consisting of tree canopy (ETabove) and its underlying surface (ETsubcanopy) dominate ET. The challenge arises from the fact that classical eddy covariance 1) directly only measures total ET and 2) biases in the respective energy balance are often observed. Here, we address these challenges in a Mediterranean savannah tree-grass ecosystem, by synchronous, combined measurements via classical eddy covariance, sub-canopy eddy covariance, sap-flow, and replicated lysimeters. To this end, half-hourly latent heat fluxes of the grass layer estimated using six novel lower boundary-tension and -temperature controlled lysimeters (LEsubcanopy-lysimeter)were compared to those measured by a sub-canopy eddy covariance tower placed at 1.8 m (LEsubcanopy-eddy) over a year. To explain the residuals (epsilon) between LEsubcanopy-lysimeter and LEsubcanopy-eddy , we trained a random forest model (RF) using soil moisture (SM), ground-heat fluxes (G), net radiation (Rn), air relative humidity (RH) and friction velocity (u*) as main predictor variables. The degree of energy closure was evaluated by comparing residual LE (LEresidual, estimated as Rn-H-G; H denotes sensible heat flux) against total LE measured by a tall tower installed above the canopy at 15 m (LEeddy). In parallel, we contrasted this using independent, upscaled LE (LEupscaled= LEsubcanopy-lysimeter + LEabove-sapflow; being LEabove-sapflow the tree component derived from sap-flow measurements) to test whether failures in LEeddy explain the lack of energy balance closure. In such a case, we test the use of RF as a generalized approach to estimate epsilon and correct for LEeddy (LEeddy-corrected = LEeddy + epsilon). As main results, the comparison of independent LEsubcanopy-eddy and LEsubcanopy-lysimeter evidenced that eddy

  8. Energy Landscape of Social Balance

    NASA Astrophysics Data System (ADS)

    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.

  9. Suburban Energy Balance Estimates for Vancouver, B.C., Using the Bowen Ratio-Energy Balance Approach.

    NASA Astrophysics Data System (ADS)

    Kalanda, B. D.; Oke, T. R.; Spittlehouse, D. L.

    1980-07-01

    The energy balance of a suburban site in Vancouver, B.C. in late summer is presented. The balance is obtained from direct measurements of net radiation, parameterized heat storage and turbulent fluxes determined according to the Bowen ratio-energy balance method with reversing psychrometers. An error analysis shows the turbulent fluxes are good to within 10-20% by day. Features of the suburban energy balance are found to be intermediate between those previously reported for urban and rural surfaces. Average daytime Bowen ratios are usually in the range 0.5-1.0 with some days as high as 2.5. The daytime sensible heat flux is in-phase with the net radiation. At night this flux is sometimes positive. Evapotranspiration is always an important term in the balance. The role of urban irrigation and microscale heat advection in maintaining evapotranspiration rates is discussed.

  10. Glial cells and energy balance.

    PubMed

    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.

  11. Exercise patterns, ingestive behaviors, and energy balance.

    PubMed

    Li, Jia; O'Connor, Lauren E; Zhou, Jing; Campbell, Wayne W

    2014-07-01

    Ingestive and exercise behaviors are important determinants of whole body energy balance and weight control. An acute bout of exercise generates a transient energy deficit, which is only partially compensated for by food intake at the next eating occasion or within the next day (loose dietary coupling). Such an energy deficit, when repeated chronically, leads to moderate weight loss and improved body composition. For this narrative review, we assessed the effects of exercise patterns on energy intake, energy balance, and weight control in adults primarily using results from randomized acute exercise and chronic training studies. The patterns assessed were exercise mode (e.g. resistance, aerobic exercise), intensity, duration, time of day, and frequency. The body of evidence indicates that exercise training frequency and quantity are influential for weight loss. Aerobic training is superior to resistance training for weight loss, although resistance training helps preserve lean body mass better. Weight loss does not differ among different intensities when energy expenditure is matched by adjusting duration. Differing patterns of physical activity exhibited by normal weight, overweight, and obese people during weekdays and weekend days are consistent with their weight status; leaner people are more physically active. Collectively, these findings support acute and chronic exercise patterns as important modifiable behaviors to improve energy balance and weight control in adults while having minor effects on absolute energy intake.

  12. Analysis of surface energy balance closure over heterogeneous surfaces

    NASA Astrophysics Data System (ADS)

    Kim, Soojin; Lee, Young-Hee; Kim, Kyu Rang; Park, Young-San

    2014-11-01

    Surface energy balance closure has been examined using eddy covariance measurements and other observations at one industrial and three agricultural sites near the Nakdong River during daytime. Energy balance closure was evaluated by calculating the long-term averaged energy balance ratio (EBR), the ratio of turbulent energy fluxes to available energy, and the statistical regression of turbulent energy fluxes against available energy using half-hourly data. The EBR of all sites ranges from 0.46 to 0.83 while the coefficient of determination ( R 2) ranges from 0.37 to 0.77. The energy balance closure was relatively poor compared to homogeneous sites, indicating the influence of surface heterogeneity. Unmeasured heat storage terms also seem to play a role in the surface energy budget at the industrial and irrigated sites. The energy balance closure was better in conditions of high wind speed, low downward short wave radiation, and high friction velocity, which suggests the role of heat storage term and surface heterogeneity in surface energy balance at these sites. Spectrum analysis shows a sharp roll-off at the low frequency in co-spectrum, which indicates that low-frequency motions do not significantly contribute to turbulent fluxes. Both the spectra and cospectra in unstable conditions show a broad peak indicating the influence of multiple sizes of large eddies over heterogeneous sites. Most of ogive curves for the kinematic latent and sensible heat fluxes reach an asymptote within 30 minutes regardless of the EBR value, indicating that low frequency motion is not a main factor for energy imbalance. However, stationary eddies due to landscape heterogeneity still remains as a possible cause for energy imbalance.

  13. Global information balance in quantum measurements.

    PubMed

    Buscemi, Francesco; Hayashi, Masahito; Horodecki, Michał

    2008-05-30

    We perform an information-theoretical analysis of quantum measurement processes and obtain the global information balance in quantum measurements, in the form of a closed chain equation for quantum mutual entropies. Our balance provides a tight and general entropic information-disturbance trade-off, and explains the physical mechanism underlying it. Finally, the single-outcome case, that is, the case of measurements with posts election, is briefly discussed.

  14. An energy balance concept for habitability.

    PubMed

    Hoehler, Tori M

    2007-12-01

    Habitability can be formulated as a balance between the biological demand for energy and the corresponding potential for meeting that demand by transduction of energy from the environment into biological process. The biological demand for energy is manifest in two requirements, analogous to the voltage and power requirements of an electrical device, which must both be met if life is to be supported. These requirements exhibit discrete (non-zero) minima whose magnitude is set by the biochemistry in question, and they are increased in quantifiable fashion by (i) deviations from biochemically optimal physical and chemical conditions and (ii) energy-expending solutions to problems of resource limitation. The possible rate of energy transduction is constrained by (i) the availability of usable free energy sources in the environment, (ii) limitations on transport of those sources into the cell, (iii) upper limits on the rate at which energy can be stored, transported, and subsequently liberated by biochemical mechanisms (e.g., enzyme saturation effects), and (iv) upper limits imposed by an inability to use "power" and "voltage" at levels that cause material breakdown. A system is habitable when the realized rate of energy transduction equals or exceeds the biological demand for energy. For systems in which water availability is considered a key aspect of habitability (e.g., Mars), the energy balance construct imposes additional, quantitative constraints that may help to prioritize targets in search-for-life missions. Because the biological need for energy is universal, the energy balance construct also helps to constrain habitability in systems (e.g., those envisioned to use solvents other than water) for which little constraint currently exists.

  15. Kisspeptin and energy balance in reproduction.

    PubMed

    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.

  16. Nexus of poverty, energy balance and health.

    PubMed

    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

  17. Energy balance of the collisional tearing mode

    SciTech Connect

    Bondeson, A.; Sobel, J.R.

    1984-08-01

    The energy balance of the collisional tearing mode is examined within linear theory. It is found that in an asymmetric case the quadratic form given by Furth for the net release of magnetic energy must be completed with a term connected with the current gradient in the resistive layer. The growth-rate and the inner-layer solution are calculated in the limit where viscosity dominates over inertia. The amounts of energy going into Joule heating and either kinetic energy or viscous dissipation are calculated analytically. In the inertial regime 1/4 of the net decrease in magnetic energy goes into kinetic energy and (3)/(4) into Joule heating, while, in viscous regime, (1)/(6) goes into viscous dissipation and (5)/(6) into Joule heating. The analytical results, based on the constant-psi approximation, are in good agreement with numerical simulations when the resistive layer is sufficiently narrow.

  18. Importance of energy balance in agriculture.

    NASA Astrophysics Data System (ADS)

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

    2012-04-01

    Since the beginning, man has tried to control nature and the environment, and the use of energy, mainly from non-renewable sources providing the necessary power for that. The consequences of this long fight against nature has reached a critical state of unprecedented worldwide environmental degradation, as evidenced by the increasing erosion of fertile lands, the deforestation processes, the pollution of water, air and land by agrochemicals, the loss of plant and animal species, the progressive deterioration of the ozone layer and signs of global warming. This is exacerbated by the increasing population growth, implying a steady increase in consumption, and consequently, in the use of energy. Unfortunately, all these claims are resulting in serious economic and environmental problems worldwide. Because the economic and environmental future of the countries is interrelated, it becomes necessary to adopt sustainable development models based on the use of renewable and clean energies, the search for alternative resources and the use of productive systems more efficient from an energy standpoint, always with a reduction of greenhouse gas emissions. In relation to the agricultural sector, the question we ask is: how long can we keep the current energy-intensive agricultural techniques in developed countries? To analyze this aspect, energy balance is a very helpful tool because can lead to more efficient, sustainable and environment-friendly production systems for each agro-climatic region. This requires the identification of all the inputs and the outputs involved and their conversion to energy values by means of corresponding energy coefficients or equivalents (International Federation of Institutes for Advanced Studies). Energy inputs (EI) can be divided in direct (energy directly used in farms as fuel, machines, fertilizers, seeds, herbicides, human labor, etc.) and indirect (energy not consumed in the farm but in the elaboration, manufacturing or manipulation of

  19. The energy balance of the solar transition region

    NASA Technical Reports Server (NTRS)

    Jordan, C.

    1980-01-01

    It is shown how the observed distribution of the emission measure with temperature can be used to limit the range of energy deposition functions suitable for heating the solar transition region and inner corona. The minimum energy loss solution is considered in view of the work by Hearn (1975) in order to establish further scaling laws between the transition region pressure, the maximum coronal temperature and the parameter giving the absolute value of the emission measure. Also discussed is the absence of a static energy balance at the base of the transition region in terms of measurable atmospheric parameters, and the condition for a static energy balance is given. In addition, the possible role of the emission from He II in stabilizing the atmosphere by providing enhanced radiation loss is considered.

  20. Energy and mass balance calculations for incinerators

    SciTech Connect

    Lee, C.C.; Huffman, G.L.

    1998-01-01

    Calculation of energy and mass balance within an incinerator is a very important part of designing and/or evaluating the incineration process. This article describes a simple computer model used to calculate an energy and mass balance for a rotary kiln incinerator. The main purpose of the model is to assist US Environmental Protection Agency (EPA) permit writers in evaluating the adequacy of the data submitted by applicants seeking incinerator permits. The calculation is based on the assumption that a thermodynamic equilibrium condition exits within the combustion chamber. Key parameters that the model can calculate include theoretical combustion air, excess air needed for actual combustion cases, flue gas flow rate, and exit temperature.

  1. Surface energy balance calculations for small northern lakes

    NASA Astrophysics Data System (ADS)

    Binyamin, J.; Rouse, W. R.; Davies, J. A.; Oswald, C. J.; Schertzer, W. M.

    2006-12-01

    An energy balance model is used to determine diurnal surface energy balance components for three different sized high-latitude Canadian lakes in the Mackenzie River Basin (MRB) during the open water seasons of 2000, 2001, and 2002. Surface net radiation is derived from the component fluxes of the radiation balance. Turbulent heat fluxes are calculated using the aerodynamic method with input from local meteorological stations and experimentally derived drag coefficients. Lake heat storage, determined as a residual of the surface energy balance, is used together with measured water temperature profiles to calculate the daily mixing layer depth. The model uses readily available meteorological inputs for radiation calculations.Verification results for surface energy balance components show mean bias error (MBE) generally less than 5% of the mean measured daily fluxes and root mean square error (RMSE) less than 38%, which decreases to less than 16% for 10-day averaging periods. The model tends to overestimate net radiation by 7% and latent and sensible heat fluxes by about 4% and 1%, respectively, on average. Inferred slab layer depths indicate that the shallowest lake was isothermal while the deeper lakes showed temporal variations as expected.

  2. Energy-balanced algorithm for RFID estimation

    NASA Astrophysics Data System (ADS)

    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.

  3. Gut microbiota, nutrient sensing and energy balance.

    PubMed

    Duca, F A; Lam, T K T

    2014-09-01

    The gastrointestinal (GI) tract is a highly specialized sensory organ that provides crucial negative feedback during a meal, partly via a gut-brain axis. More specifically, enteroendocrine cells located throughout the GI tract are able to sense and respond to specific nutrients, releasing gut peptides that act in a paracrine, autocrine or endocrine fashion to regulate energy balance, thus controlling both food intake and possibly energy expenditure. Furthermore, the gut microbiota has been shown to provide a substantial metabolic and physiological contribution to the host, and metabolic disease such as obesity has been associated with aberrant gut microbiota and microbiome. Interestingly, recent evidence suggests that the gut microbiota can impact the gut-brain axis controlling energy balance, at both the level of intestinal nutrient-sensing mechanisms, as well as potentially at the sites of integration in the central nervous system. A better understanding of the intricate relationship between the gut microbiota and host energy-regulating pathways is crucial for uncovering the mechanisms responsible for the development of metabolic diseases and for possible therapeutic strategies.

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

    ERIC Educational Resources Information Center

    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…

  5. Energy balance in the WTC collapse

    NASA Astrophysics Data System (ADS)

    Zhu, Kaiqi; Xu, Kang; Ansourian, Peter; Tahmasebinia, Faham; Alonso-Marroquin, Fernando

    2016-08-01

    The main aim of this report is to provide an analysis of Twin Towers of the New York City's World Trade Centre collapsed after attacked by two jet aircrafts. The approach mainly focused on the effect of temperature on mechanical properties of the building, by modelling heat energy in the south tower. Energy balance during the collapse between the energy inputs by aircraft petrol and the transient heat to the towers was conducted. Both the overall structure between 80 to 83 stories and individual elements was modelled. The main elements contributed to the heat transition includes external and internal columns. Heat applied in 2D and 3D models for single elements was through convection and conduction. Analysis of transient heat was done using Strand7.

  6. The Global Energy Balance of Titan

    NASA Technical Reports Server (NTRS)

    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; Baines, Kevin H.; Ingersoll, Andrew P.; West, Robert A.; Vasavada, Ashwin R.; Ewald, Shawn P.

    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%.

  7. Energy Balance Bowen Ratio Station (EBBR) Handbook

    SciTech Connect

    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.

  8. Energy Balance Bowen Ratio (EBBR) Handbook

    SciTech Connect

    Cook, D. R.

    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.

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

    NASA Technical Reports Server (NTRS)

    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.

  10. High-intensity sweeteners and energy balance.

    PubMed

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

    2010-04-26

    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.

  11. Exercise, energy balance and the shift worker.

    PubMed

    Atkinson, Greg; Fullick, Sarah; Grindey, Charlotte; Maclaren, Don

    2008-01-01

    Shift work is now common in society and is not restricted to heavy industry or emergency services, but is increasingly found amongst 'white collar' occupations and the growing number of service industries. Participation in shift work is associated with increased body mass index, prevalence of obesity and other health problems. We review the behavioural and biological disturbances that occur during shift work and discuss their impact on leisure-time physical activity and energy balance. Shift work generally decreases opportunities for physical activity and participation in sports. For those shift workers who are able to exercise, subjective and biological responses can be altered if the exercise is taken at unusual times of day and/or if the shift worker is sleep deprived. These altered responses may in turn impact on the longer-term adherence to an exercise programme. The favourable effects of exercise on body mass control and sleep quality in shift workers have not been confirmed. Similarly, recent reports of relationships between sleep duration and obesity have not been examined in a shift work context. There is no evidence that exercise can mediate certain circadian rhythm characteristics (e.g. amplitude or timing) for improved tolerance to shift work. Total energy intake and meal composition do not seem to be affected by participation in shift work. Meal frequency is generally reduced but snacking is increased on the night shift. Unavailability of preferred foods in the workplace, a lack of time, and a reduced desire to eat at night explain these findings. 'Normal' eating habits with the family are also disrupted. The metabolic responses to food are also altered by shift work-mediated disruptions to sleep and circadian rhythms. Whether any interactions on human metabolism exist between timing or content of food intake and physical activity during shift work is not known at present. There are very few randomized controlled studies on the efficacy of physical

  12. Observations in energy balance in man during spaceflight

    NASA Technical Reports Server (NTRS)

    Rambaut, P. C.; Leach, C. S.; Leonard, J. I.

    1977-01-01

    An investigation was undertaken of the changes in metabolic energy balance which occur in weightlessness. Daily energy intake was determined each day throughout the 28-, 59-, and 84-day flights for each of the nine Skylab astronauts. The energy content of the urine and feces was also measured. Changes in body composition were inferred from measurements of weight, volume, water, and total exchangeable potassium before and after flight. During flight, changes were followed by a daily measurement of body mass and by metabolic balance. Examination of the data reveal losses in body weight during the 1st and 2nd months of flight, a loss in body water and protein during the 1st month and a loss of fat during the 1st, 2nd, and 3rd months of flight. The energy input was about 41.7 kcal/kg per day on the ground, and 43.7 kcal/kg per day after 3 months in space. The increase in net energy input of about 1.6% per month is significant (P less than 0.05). When the net energy input is expressed on the basis of total body potassium, the increase in the resulting normalized net energy input of about 3.7% per month is also significant (P less than 0.05).

  13. Accounting for minor storage terms in an attempt to close the measured surface energy balance over a winter wheat field in Southwest Germany

    NASA Astrophysics Data System (ADS)

    Eshonkulov, Ravshan; Poyda, Arne; Ingwersen, Joachim; Streck, Thilo

    2016-04-01

    Studies of energy and water exchange between the land surface and the atmospheric boundary layer are important to understand weather dynamics and climate change. Energy and water fluxes were measured on a winter wheat field in Kraichgau, Southern Germany, using the eddy covariance (EC) method. It is well known that EC measurements suffer from incomplete closure of the energy budget. In addition to the common ground heat flux measurements we measured heat storage in soil and the wheat canopy using high-precision temperature loggers within the EC footprint. Ground heat flux was re-calculated by calorimetric and harmonic analysis. First results obtained by the two methods will be compared. Based on measured data we calculated the contribution of photosynthesis, the air heat storage inside the canopy as well as the atmospheric moisture change to the energy budget. Our results show that accounting for minor storage terms improves the closure of the energy budget, but only to a limited extent. Further investigations will be necessary to identify additional sources of the energy gap typical for EC measurements.

  14. Sleep patterns, diet quality and energy balance.

    PubMed

    Chaput, Jean-Philippe

    2014-07-01

    There is increasing evidence showing that sleep has an influence on eating behaviors. Short sleep duration, poor sleep quality, and later bedtimes are all associated with increased food intake, poor diet quality, and excess body weight. Insufficient sleep seems to facilitate the ingestion of calories when exposed to the modern obesogenic environment of readily accessible food. Lack of sleep has been shown to increase snacking, the number of meals consumed per day, and the preference for energy-rich foods. Proposed mechanisms by which insufficient sleep may increase caloric consumption include: (1) more time and opportunities for eating, (2) psychological distress, (3) greater sensitivity to food reward, (4) disinhibited eating, (5) more energy needed to sustain extended wakefulness, and (6) changes in appetite hormones. Globally, excess energy intake associated with not getting adequate sleep seems to be preferentially driven by hedonic rather than homeostatic factors. Moreover, the consumption of certain types of foods which impact the availability of tryptophan as well as the synthesis of serotonin and melatonin may aid in promoting sleep. In summary, multiple connections exist between sleep patterns, eating behavior and energy balance. Sleep should not be overlooked in obesity research and should be included as part of the lifestyle package that traditionally has focused on diet and physical activity.

  15. Components of surface energy balance in a temperate grassland ecosystem

    NASA Technical Reports Server (NTRS)

    Kim, Joon; Verma, Shashi B.

    1990-01-01

    Eddy correlation measurements of moisture, heat, and momentum fluxes were made at a tall grassland site in Kansas during the First International Satellite Land Surface Climatology Project Field Experiment. The fluxes, stomatal conductance, and leaf water potential of three grass species are reported. The species are big bluestem, indiangrass, and switchgrass. The daily and seasonal variation in the components of the surface energy balance and the aerodynamic and canopy surface conductances for prairie vegetation are examined.

  16. Energy Balance Models and Planetary Dynamics

    NASA Technical Reports Server (NTRS)

    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.

  17. Energy expenditure and balance during spaceflight on the space shuttle

    NASA Technical Reports Server (NTRS)

    Stein, T. P.; Leskiw, M. J.; Schluter, M. D.; Hoyt, R. W.; Lane, H. W.; Gretebeck, R. E.; LeBlanc, A. D.

    1999-01-01

    The objectives of this study were as follows: 1) to measure human energy expenditure (EE) during spaceflight on a shuttle mission by using the doubly labeled water (DLW) method; 2) to determine whether the astronauts were in negative energy balance during spaceflight; 3) to use the comparison of change in body fat as measured by the intake DLW EE, 18O dilution, and dual energy X-ray absorptiometry (DEXA) to validate the DLW method for spaceflight; and 4) to compare EE during spaceflight against that found with bed rest. Two experiments were conducted: a flight experiment (n = 4) on the 16-day 1996 life and microgravity sciences shuttle mission and a 6 degrees head-down tilt bed rest study with controlled dietary intake (n = 8). The bed rest study was designed to simulate the flight experiment and included exercise. Two EE determinations were done before flight (bed rest), during flight (bed rest), and after flight (recovery). Energy intake and N balance were monitored for the entire period. Results were that body weight, water, fat, and energy balance were unchanged with bed rest. For the flight experiment, decreases in weight (2.6 +/- 0.4 kg, P < 0.05) and N retention (-2. 37 +/- 0.45 g N/day, P < 0.05) were found. Dietary intake for the four astronauts was reduced in flight (3,025 +/- 180 vs. 1,943 +/- 179 kcal/day, P < 0.05). EE in flight was 3,320 +/- 155 kcal/day, resulting in a negative energy balance of 1,355 +/- 80 kcal/day (-15. 7 +/- 1.0 kcal. kg-1. day-1, P < 0.05). This corresponded to a loss of 2.1 +/- 0.4 kg body fat, which was within experimental error of the fat loss determined by 18O dilution (-1.4 +/- 0.5 kg) and DEXA (-2.4 +/- 0.4 kg). All three methods showed no change in body fat with bed rest. In conclusion, 1) the DLW method for measuring EE during spaceflight is valid, 2) the astronauts were in severe negative energy balance and oxidized body fat, and 3) in-flight energy (E) requirements can be predicted from the equation: E = 1.40 x resting

  18. Appetite and energy balance signals from adipocytes

    PubMed Central

    Trayhurn, Paul; Bing, Chen

    2006-01-01

    Interest in the biology of white adipose tissue has risen markedly with the recent surge in obesity and its associated disorders. The tissue is no longer viewed simply as a vehicle for lipid storage; instead, it is recognized as a major endocrine and secretory organ. White adipocytes release a multiplicity of protein hormones, signals and factors, termed adipokines, with an extensive range of physiological actions. Foremost among these various adipokines is the cytokine-like hormone, leptin, which is synthesized predominantly in white fat. Leptin plays a critical role in the control of appetite and energy balance, with mutations in the genes encoding the hormone or its receptor leading to profound obesity in both rodents and man. Leptin regulates appetite primarily through an interaction with hypothalamic neuroendocrine pathways, inhibiting orexigenic peptides such as neuropeptide Y and orexin A, and stimulating anorexigenic peptides such as proopiomelanocortin. White fat also secretes several putative appetite-related adipokines, which include interleukin-6 and adiponectin, but whether these are indeed significant signals in the regulation of food intake has not been established. Through leptin and the other adipokines it is evident that adipose tissue communicates extensively with other organs and plays a pervasive role in metabolic homeostasis. PMID:16815801

  19. Balancing Energy-Water-Agriculture Tradeoffs

    NASA Astrophysics Data System (ADS)

    Tidwell, V.; Hightower, M.

    2011-12-01

    In 2005 thermoelectric power production accounted for withdrawals of 201 billion gallons per day (BGD) representing 49% of total withdrawals, making it the largest user of water in the U.S. In terms of freshwater withdrawals thermoelectric power production is the second largest user at 140 BGD just slightly behind freshwater withdrawals for irrigation (USGS 2005). In contrast thermoelectric water consumption is projected at 3.7 BGD or about 3% of total U.S. consumption (NETL 2008). Thermoelectric water consumption is roughly equivalent to that of all other industrial demands and represents one of the fastest growing sectors since 1980. In fact thermoelectric consumption is projected to increase by 42 to 63% between 2005 and 2030 (NETL 2008). Agricultural water consumption has remained relatively constant at roughly 84 BGD or about 84% of total water consumption. While long-term regional electricity transmission planning has traditionally focused on cost, infrastructure utilization, and reliability, issues concerning the availability of water represent an emerging issue. Thermoelectric expansion must be considered in the context of competing demands from other water use sectors balanced with fresh and non-fresh water supplies subject to climate variability. Often such expansion targets water rights transfers from irrigated agriculture. To explore evolving tradeoffs an integrated energy-water-agriculture decision support system has been developed. The tool considers alternative expansion scenarios for the future power plant fleet and the related demand for water. The availability of fresh and non-fresh water supplies, subject to local institutional controls is then explored. This paper addresses integrated energy-water-agriculture planning in the western U.S. and Canada involving an open and participatory process comprising decision-makers, regulators, utility and water managers.

  20. ANALYSIS OF WATER AND ENERGY FLUXES USING SATELLITE, ENERGY BALANCE MODELING AND OBSERVATIONS (Invited)

    NASA Astrophysics Data System (ADS)

    Irmak, A.

    2009-12-01

    Surface energy fluxes, including net radiation (Rn), sensible heat (H), latent heat (LE), and soil heat flux (G) are critical in surface energy balance of any terrain or landscapes. Estimation or measurement of these energy fluxes is important for completing the water balance in terrestrial ecosystems, and therefore accurately predicting the effects of global climate and land use change. The objectives of this study were to (1) use METRICtm (Mapping Evapotranspiration at high Resolution using Internalized Calibration) model for estimating land surface energy fluxes in Nebraska (NE) by utilizing satellite remote sensing data, (2) identify model bias in energy balance components compared with measurements from Bowen Ratio Energy Balance System (BREBS) in a subsurface drip-irrigated maize field in South-central Nebraska, and (3) understand the partitioning of available energy into latent heat for corn and soybean cropping systems at large scale. A total of 15 Landsat images were processed to estimate instantaneous surface energy fluxes at Landsat overpasses with METRIC model. Results showed that the model predictions of the surface energy fluxes and daily evapotranspiration were correlated well with the BREBS measurements. There is a need, however, to test the performance of the model with in-situ observations in other locations with different dataset before utilizing it for crucial water regulatory and policy decisions. The METRICtm approach illustrated how an ‘off-the-shelf’ model can be applied operationally over a significant time period and how that model behaves. The findings makes considerable contribution to our understanding of estimating land surface energy fluxes using remote sensing approach and experimentally describes the operational characteristics of METRICtm and presents its limitations.

  1. Validating surface energy balance fluxes derived from airborne remote sensing

    NASA Astrophysics Data System (ADS)

    Chavez Eguez, Jose Luis

    Remote sensing-derived energy balance components were compared against measured eddy covariance energy balance terms using heat flux source area models to validate the airborne multispectral remote sensing procedure in the estimation of instantaneous and daily evapotranspiration rates. A procedure was developed to generate raster layers of the footprint weights for weighting/integrating the different components of the energy balance model and obtain meaningful comparisons to similar energy balance terms measured at eddy covariance and/or Bowen ratio stations. Soil heat flux and surface aerodynamic temperature models were studied in an effort to improve the remote sensing estimation of distributed evapotranspiration rates. Aerial and ground data were acquired over a riparian corridor (Salt Cedar, Tamarix grove), soybean and cornfields (rainfed crops) in different ecosystems. The results confirmed that net radiation is well estimated with the remote sensing technique showing an estimation error of only -4.8 +/- 20.7 W m-2, (-0.5 +/- 3.6%). Linear and exponential soil heat flux models were found to correlate strongly to leaf area index and net radiation. The surface aerodynamic temperature term in the sensible heat flux equation was parameterized using surface radiometric temperature, air temperature, wind speed, and leaf area index. It is suggested that the surface aerodynamic temperature model be tested for a wide range of vegetation types, atmospheric stability conditions, surface heterogeneity, and ecosystems to assess the model limitations. The flux source area footprint model "FSAM" integrated heat flux pixels that compared better to measured values and it is recommended as a standard procedure to compare airborne remote sensing-derived heat fluxes against measured fluxes by eddy covariance systems; when compared to the "FASOWG" footprint model and simple arithmetic averages. Finally, the method that uses alfalfa reference daily evapotranspiration in

  2. Energy and Mass Balance At Gran Campo Nevado, Patagonia, Chile

    NASA Astrophysics Data System (ADS)

    Schneider, C.; Kilian, R.; Casassa, G.

    The Gran Campo Nevado (GCN) Ice Cap on Peninsula Muñoz Gamero, Chile, is lo- cated in the southernmost part of the Patagonian Andes at 53S. It comprises an ice cap and numerous outlet glaciers which mostly end in proglacial lakes at sea level. The total ice covered area sums up to approximately 250 km2. GCN forms the only major ice body between the Southern Patagonian Icefield and the Street of Magallan. Its almost unique location in the zone of the all-year westerlies makes it a region of key interest in terms of glacier and climate change studies of the westwind zone of the Southern Hemisphere. Mean annual temperature of approximately +5C at sea level and high precipitation of about 8.000 mm per year lead to an extreme turn-over of ice mass from the accumulation area of the GCN Ice Cap to the ablation areas of the outlet glaciers. Since October 1999 an automated weather station (AWS) is run continuously in the area at Bahia Bahamondes for monitoring climate parameters. From February to April 2000 an additional AWS was operated on Glaciar Lengua a small outlet glacier of GCN to the north-west. Ablation has been measured at stakes during the same pe- riod. The aim of this study, was to obtain point energy and mass balance on Glaciar Lengua. The work was conducted as part of the international and interdisciplinary working group SGran Campo NevadoT and supported by the German Research Foun- & cedil;dation (DFG). Energy balance was calculated using the bulk approach formulas and calibrated to the measured ablation. It turns out, that sensible heat transfer is the major contribution to the energy balance. Since high cloud cover rates prevail, air tempera- ture is the key factor for the energy balance of the glacier. Despite high rain fall rates, energy input from rain fall is of only minor importance to the overall energy balance. From the energy balance computed, it was possible to derive summer-time degree-day factors for Glaciar Lengua. With data from the nearby

  3. Earth's Energy Balance From Space: A 35 Year Perspective

    NASA Astrophysics Data System (ADS)

    Wielicki, B. A.

    2005-12-01

    The Earth's radiative energy balance is the most fundamental driver of long term climate. Changes of 1% or less are sufficient to cause major climate change. Earth orbiting satellites provide the optimal platform to observe this energy balance, and efforts began with Nimbus 3 in 1969. Prior to satellite missions, the Earths reflected and emitted radiation were estimated using earthshine from the moon, or by a radiative transfer calculation using surface observations of aerosol, cloud, temperature, humidity, and ozone. Observing the earths radiation balance from space is an 8-dimensional sampling problem, with a requirement for extremely high accuracy and stability to directly observe climate signals. The challenge is especially severe for decadal changes in aerosols and clouds. A perspective is given on the dramatic progress that has occurred in measuring radiation in space, from Nimbus 3 in 1969 to current CERES global and GERB geostationary observations. A vision for future advances in these observations as part of the global climate observing system is also given, including new ways to use the data in unscrambling the effects of aerosol indirect effects as well as cloud feedback in the climate system. These last two issues provide extraordinary challenges in climate forcing and climate sensitivity respectively.

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

    PubMed

    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 < 0.05) and fullness (P = 0.01) were measured every waking hour and before and after every meal using visual analogue scales, and were higher in the 100%CAPS versus 100%Control condition. After dinner desire to eat, satiety and fullness did not differ between 75%CAPS and 100%Control, while desire to eat was higher (P < 0.05) and satiety (P = 0.06) and fullness (P = 0.06) tended to be lower in the 75%Control versus 100%Control condition. Furthermore, ad libitum intake (P = 0.07) and overconsumption (P = 0.06) tended to decrease in 100%CAPS versus 100%Control. In 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.

  5. Balanced interferometric system for stability measurements

    SciTech Connect

    Ellis, Jonathan D.; Joo, Ki-Nam; Spronck, Jo W.; Munnig Schmidt, Robert H

    2009-03-20

    We describe two different, double-sided interferometer designs for measuring material stability. Both designs are balanced interferometers where the only optical path difference is the sample and the reference beams are located within the interferometer. One interferometer is a double-pass design, whereas the other is a single-pass system. Based on a tolerancing analysis, the single-pass system is less susceptible to initial component misalignment and motions during experiments. This single-pass interferometer was tested with an 86 nm thin-film silver sample for both short-term repeatability and long-term stability. In 66 repeatability tests of 30 min each, the mean measured drift rate was less than 1 pm/h rms. In two long-term tests (>9 h), the mean drift rate was less than 1.1 pm/h, which shows good agreement between the short- and long-term measurements. In these experiments, the mean measured length change was 2 nm rms.

  6. Runoff, precipitation, mass balance, and ice velocity measurements at South Cascade Glacier, Washington, 1993 balance year

    USGS Publications Warehouse

    Krimmel, R.M.

    1994-01-01

    Winter snow accumulation and summer snow, firn, and ice ablation were measured at South Cascade Glacier, Wash., to determine the winter and net balance for the 1993 balance year. The 1993 winter balance, averaged over the glacier, was 1.98 meters, and the net balance was -1.23 meters. This negative valance continued a trend of negative balance years beginning in 1977. Air temperature, barometric pressure, and runoff from this glacier basin and an adjacent non-glacierized basin were also continuously measured. Surface ice velocity was measured over an annual period. This report makes all these data available to users throughout the glaciological and climato1ogical community.

  7. [Energy balance, body composition and the female athlete triad syndrome].

    PubMed

    Weinstein, Yitzhak; Weinstein, Ayelet

    2012-02-01

    With the rising participation of women in sports events, the prevalence of eating disorders and the female athlete triad (FTS), a syndrome of disordered eating, amenorrhea, and osteoporosis, have also increased in recent years. FTS is often seen in sports that emphasize thinness (e.g. gymnastics, figure skating and dancing) and also in endurance events. Elements of the FTS are pathophysiologically linked, leading to several disease risks and even to mortality. In spite of the considerable knowledge about sports nutrition, there is no consensus as to the correct nutrition regime for the female athlete. There is consensus that minimizing fluctuations in 'target-body-weight' is an indication of a long-term energy balance. Female athletes (e.g. in endurance events and gymnastics) are less likely to achieve the recommended carbohydrates (CHO) and fat consumption due to chronic or episodic constraints of total energy intake while struggling to achieve or maintain low levels of body fat. It is recommended that dietary CHO and fat content be increased to preserve fat-free mass thus enhancing health and performance. Energy balance should also be maintained during recesses. Furthermore, within-day episodes of energy deficits/surplus (measured by the frequency and/or magnitude of the episodes) should be monitored and treated closest to the time of the incidents.

  8. Alternative energy balances for Bulgaria to mitigate climate change

    SciTech Connect

    Christov, C.

    1996-09-01

    Alternative energy balances aimed to mitigate greenhouse gas (GHG) emissions are developed as alternatives to the baseline energy balance. The section of mitigation options is based on the results of the GHG emission inventory for the 1987-1992 period. The energy sector is the main contributor to the total CO{sub 2} emissions of Bulgaria. Stationary combustion for heat and electricity production as well as direct end-use combustion amounts to 80% of the total emissions. The parts of the energy network that could have the biggest influence on GHG emission reduction are identified. The potential effects of the following mitigation measures are discussed: rehabilitation of the combustion facilities currently in operation; repowering to natural gas; reduction of losses in thermal and electrical transmission and distribution networks; penetration of new combustion technologies; tariff structure improvement; renewable sources for electricity and heat production; waste-heat utilization; and supply of households with natural gas to substitute for electricity in space heating and cooking. The total available and the achievable potentials are estimated and the implementation barriers are discussed. 3 refs.

  9. Alternative energy balances for Bulgaria to mitigate climate change

    NASA Astrophysics Data System (ADS)

    Christov, Christo

    1996-01-01

    Alternative energy balances aimed to mitigate greenhouse gas (GHG) emissions are developed as alternatives to the baseline energy balance. The section of mitigation options is based on the results of the GHG emission inventory for the 1987 1992 period. The energy sector is the main contributor to the total CO2 emissions of Bulgaria. Stationary combustion for heat and electricity production as well as direct end-use combustion amounts to 80% of the total emissions. The parts of the energy network that could have the biggest influence on GHG emission reduction are identified. The potential effects of the following mitigation measures are discussed: rehabilitation of the combustion facilities currently in operation; repowering to natural gas; reduction of losses in thermal and electrical transmission and distribution networks; penetration of new combustion technologies; tariff structure improvement; renewable sources for electricity and heat production; wasteheat utilization; and supply of households with natural gas to substitute for electricity in space heating and cooking. The total available and the achievable potentials are estimated and the implementation barriers are discussed.

  10. The brain endocannabinoid system in the regulation of energy balance.

    PubMed

    Richard, Denis; Guesdon, Benjamin; Timofeeva, Elena

    2009-02-01

    The role played by the endocannabinoid system in the regulation of energy balance is currently generating a great amount of interest among several groups of investigators. This interest in large part comes from the urgent need to develop anti-obesity and anti-cachexia drugs around target systems (such as the endocannabinoid system), which appears to be genuinely involved in energy balance regulation. When activated, the endocannabinoid system favors energy deposition through increasing energy intake and reducing energy expenditure. This system is activated in obesity and following food deprivation, which further supports its authentic function in energy balance regulation. The cannabinoid receptor type 1 (CB1), one of the two identified cannabinoid receptors, is expressed in energy-balance brain structures that are also able to readily produce or inactivate N-arachidonoyl ethanolamine (anandamide) and 2-arachidonoylglycerol (2AG), the most abundantly formed and released endocannabinoids. The brain action of endocannabinoid system on energy balance seems crucial and needs to be delineated in the context of the homeostatic and hedonic controls of food intake and energy expenditure. These controls require the coordinated interaction of the hypothalamus, brainstem and limbic system and it appears imperative to unravel those interplays. It is also critical to investigate the metabolic endocannabinoid system while considering the panoply of functions that the endocannabinoid system fulfills in the brain and other tissues. This article aims at reviewing the potential mechanisms whereby the brain endocannabinoid system influences the regulation energy balance.

  11. Serotonin and the regulation of mammalian energy balance

    PubMed Central

    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. PMID:23543912

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

    ERIC Educational Resources Information Center

    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. Melanocortin control of energy balance: evidence from rodent models.

    PubMed

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

    2011-08-01

    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 longterm 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.

  14. Hypothalamic proopiomelanocortin processing and the regulation of energy balance

    PubMed Central

    Wardlaw, Sharon L.

    2011-01-01

    Hypothalamic proopiomelanocortin (POMC) neurons play a key role in regulating energy balance and neuroendocrine function. Much attention has been focused on regulation of POMC gene expression with less emphasis on regulated peptide processing. This is particularly important given the complexity of posttranslational POMC processing which is essential for the generation of biologically active MSH peptides. Mutations that impair POMC sorting and processing are associated with obesity in humans and in animals. Specifically, mutations in the POMC processing enzymes prohormone convertase 1/3 (PCI/3) and in carboxypeptidase E (CPE) and in the α-MSH degrading enzyme, PRCP, are associated with changes in energy balance. There is increasing evidence that POMC processing is regulated with respect to energy balance. Studies have implicated both the leptin and insulin signaling pathways in the regulation of POMC at various steps in the processing pathway. This article will review the role of hypothalamic POMC in regulating energy balance with a focus on POMC processing. PMID:21208604

  15. Analysis of energy balance models using the ERBE data set

    NASA Technical Reports Server (NTRS)

    Graves, Charles E.; North, Gerald R.

    1991-01-01

    A review of Energy Balance Models is presented. Results from the Outgoing Longwave Radiation parameterization are discussed. The albedo parameterizations and the consequences of the new parameterizations are examined.

  16. Top 10 Research Questions Related to Energy Balance

    ERIC Educational Resources Information Center

    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…

  17. Components of surface energy balance in a temperate grassland ecosystem

    NASA Astrophysics Data System (ADS)

    Kim, Joon; Verma, Shashi B.

    1990-06-01

    Eddy correlation measurements were made of fluxes of moisture, heat and momentum at a tallgrass prairie site near Manhattan, Kansas, U.S.A. during the First ISLSCP ISLSCP: International Satellite Land Surface Climatology Project (for details, see Sellers et al., 1988). Field Experiment (FIFE) in 1987. The study site is dominated by three C4 grass species: big bluestem ( Andropogon gerardii), indiangrass ( Sorghastrum nutans), and switchgrass ( Panicum virgatum). The stomatal conductance and leaf water potential of these grass species were also measured. In this paper, daily and seasonal variations in the components of the surface energy balance are examined. The aerodynamic and canopy surface conductances for the prairie vegetation are also evaluated.

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

    PubMed Central

    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 pharmacotherapeutic and surgical interventions for the treatment of obesity and diabetes. PMID:25815991

  19. BALANCE (Bioengineering Approaches for Lifestyle Activity and Nutrition Continuous Engagement): Developing New Technology for Monitoring Energy Balance in Real Time

    PubMed Central

    Hughes, Deonna C.; Andrew, Adrienne; Denning, Tamara; Hurvitz, Philip; Lester, Jonathan; Beresford, Shirley; Borriello, Gaetano; Bruemmer, Barbara; Moudon, Anne Vernez; Duncan, Glen E.

    2010-01-01

    Methods that measure energy balance accurately in real time represent promising avenues to address the obesity epidemic. We developed an electronic food diary on a mobile phone that includes an energy balance visualization and computes and displays the difference between energy intake from food entries and energy expenditure from a multiple-sensor device that provides objective estimates of energy expenditure in real time. A geographic information system dataset containing locations associated with activity and eating episodes is integrated with an ArcPad mapping application on the phone to provide users with a visual display of food sources and locations associated with physical activity within their proximal environment. This innovative tool captures peoples' movement through space and time under free-living conditions and could potentially have many health-related applications in the future. PMID:20307404

  20. Balancing the energy equation for healthy kidneys.

    PubMed

    Mount, Peter F; Power, David A

    2015-12-01

    The high-energy requirement of the kidney and the importance of energy metabolism in renal physiology has been appreciated for decades, but only recently has there emerged a strong link between impaired renal energy metabolism and chronic kidney disease (CKD). The mechanisms underlying the association between changes in energy metabolism and progression of CKD, however, remain poorly understood. A new study from Qiu and colleagues reported in the Journal of Pathology has advanced this understanding by showing that, after renal injury, the energy sensor AMPK inhibits epithelial-mesenchymal transition and inflammation, processes important in the pathogenesis of CKD. Furthermore, this study identifies an interaction between AMPK and CK2β as an important mechanism in the anti-fibrotic effect. CK2β has previously been shown to interact with STK11 (also known as LKB1) to regulate cellular polarity. These findings are consistent with the known roles of the LKB1-AMPK pathway in sustaining cellular energy homeostasis and epithelial cell polarity, and add to growing evidence linking the suppression of energy metabolism to CKD. They emphasize the importance of energy metabolism in general and the LKB1-AMPK axis in particular as key investigational and therapeutic targets in the battle against CKD.

  1. Motor Energy Conservation Measures

    SciTech Connect

    Ian Metzger, Jesse Dean

    2010-12-31

    This software requires inputs of simple motor inventory information and calculates the energy and cost benefits of various retrofit opportunities. This tool includes energy conservation measures for: High Efficiency Motor retrofit and Cogged V-belts retrofit. This tool calculates energy savings, demand reduction, cost savings, and building life cycle costs including: simple payback, discounted payback, net-present value, and savings to investment ratio. In addition this tool also displays the environmental benefits of a project.

  2. Energy Balance during Taekwondo Practice in Elite Male Taekwondo Players

    PubMed Central

    Cho, Kang Ok; Garber, Carol Ewing; Lee, Sukho; Kim, Yeon Soo

    2013-01-01

    Background The goal of this study was to evaluate energy expenditure and dietary intake of nutrients during Taekwondo practice in elite Korean male Taekwondo players. Methods: Elite Korean male high school (high school player: HP; n = 59) and college players (college player: CP; n = 58) wore an accelerometer to measure energy expenditure and recorded their daily dietary intake for nutritional analysis over the course of five days. Results: Nutritional adequacy ratios for total energy (0.82), vitamin C (0.97), calcium (0.78), and folate (0.75) were below recommended levels for all players. When comparing daily nutrient intake and energy expenditure between HP and CP, the HP group had significantly higher total calorie intake (402.7 kcal, p < 0.001), calcium (126.3 mg, p = 0.018), phosphorus (198.0 mg, p = 0.002), iron (1.3 mg, p = 0.002), and vitamin B2 (0.4 mg, p < 0.001) than the CP group. Although there was no significant difference in the estimated energy requirement during Taekwondo practice, the total energy expenditure (151.2 kcal, p = 0.001), total activity counts (130,674 counts, p = 0.038) and energy expenditure during Taekwondo practice (257.7 kcal, p < 0.001) were significantly higher in the HP than in the CP. Conclusion: The results indicate that a sports nutrition program based on energy balance is necessary to achieve optimal health and performance in elite male Taekwondo players. PMID:26064838

  3. Mass balance, meteorological, and runoff measurements at South Cascade Glacier, Washington, 1992 balance year

    USGS Publications Warehouse

    Krimmel, R.M.

    1993-01-01

    Values of winter snow accumulation and summer snow, firn, and ice ablation were measured at South Cascade Glacier, WA, to determine the winter and net balance for the 1992 balance year. The 1992 winter balance, averaged over the glacier, was 1.91 m, and the net balance was -2.01 m. This extremely negative balance continued a trend of negative balance years beginning in 1977. Air temperature (at 1,615 m and 1,867 m), barometric pressure, precipitation, and runoff from this glacier basin and an adjacent non-glacierized basin were also continuously measured. This report makes all these data, in tabular, graphical, and machine-readable forms, available to users.

  4. Free energy balance in gyrokinetic turbulence

    SciTech Connect

    Banon Navarro, A.; Morel, P.; Albrecht-Marc, M.; Carati, D.; Merz, F.; Goerler, T.; Jenko, F.

    2011-09-15

    Free energy plays an important role in gyrokinetic theory, since it is known to be a nonlinear invariant. Its evolution equations are derived and analyzed for the case of ion temperature gradient driven turbulence, using the formalism adopted in the Gene code. In particular, the ion temperature gradient drive, the collisional dissipation as well as entropy/electrostatic energy transfer channels represented by linear curvature and parallel terms are analyzed in detail.

  5. Acute effect of ephedrine on 24-h energy balance

    NASA Technical Reports Server (NTRS)

    Shannon, J. R.; Gottesdiener, K.; Jordan, J.; Chen, K.; Flattery, S.; Larson, P. J.; Candelore, M. R.; Gertz, B.; Robertson, D.; Sun, M.

    1999-01-01

    Ephedrine is used to help achieve weight control. Data on its true efficacy and mechanisms in altering energy balance in human subjects are limited. We aimed to determine the acute effect of ephedrine on 24-h energy expenditure, mechanical work and urinary catecholamines in a double-blind, randomized, placebo-controlled, two-period crossover study. Ten healthy volunteers were given ephedrine (50 mg) or placebo thrice daily during each of two 24-h periods (ephedrine and placebo) in a whole-room indirect calorimeter, which accurately measures minute-by-minute energy expenditure and mechanical work. Measurements were taken of 24-h energy expenditure, mechanical work, urinary catecholamines and binding of (+/-)ephedrine in vitro to human beta1-, beta2- and beta3-adrenoreceptors. Twenty-four-hour energy expenditure was 3.6% greater (8965+/-1301 versus 8648+/-1347 kJ, P<0.05) with ephedrine than with placebo, but mechanical work was not different between the ephedrine and placebo periods. Noradrenaline excretion was lower with ephedrine (0.032+/-0.011 microg/mg creatinine) compared with placebo (0.044+/-0.012 microg/mg creatinine) (P<0.05). (+/-)Ephedrine is a relatively weak partial agonist of human beta1- and beta2-adrenoreceptors, and had no detectable activity at human beta3-adrenoreceptors. Ephedrine (50 mg thrice daily) modestly increases energy expenditure in normal human subjects. A lack of binding of ephedrine to beta3-adrenoreceptors and the observed decrease in urinary noradrenaline during ephedrine treatment suggest that the thermogenic effect of ephedrine results from direct beta1-/beta2-adrenoreceptor agonism. An indirect beta3-adrenergic effect through the release of noradrenaline seems unlikely as urinary noradrenaline decreased significantly with ephedrine.

  6. Evaporation Measured In Situ by Sensible Heat Balance

    NASA Astrophysics Data System (ADS)

    Heitman, Josh; Xiao, Xinhua; Sauer, Thomas; Ren, Tusheng; Horton, Robert

    2016-04-01

    Measurement of evaporation independent from evapotranspiration remains a major challenge for quantifying water fluxes in the soil-plant-atmosphere system. Methodology based on soil sensible heat balance (SHB) has been developed to measure in situ, sub-surface soil water evaporation with heat-pulse sensors. Soil sensible heat flux and change in heat storage are measured at multiple depths near the soil surface, and a simple energy balance calculation is applied to determine latent heat flux (i.e., evaporation) as a residual. For bare surface conditions, comparison of SHB to micrometerological (Bowen ratio) and micro-lysimeter approaches indicates strong correlation (r2 = 0.96) with near 1:1 relationship and root mean square error of 0.2 mm/d. Recent efforts to apply SHB methodology in row-crop (maize) and vineyard systems demonstrate the potential for quantifying evaporation separate from evapotranspiration. For the maize system, SHB evaporation estimates differed from micro-lysimeters by < 0.2 mm/d. The SHB approach is one of very few measurement approaches that may be applied to partition evaporation from evapotranspiration.

  7. Dietary(sensory)variety and energy balance

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The prevalence of overweight and obesity in US adults is currently 68%, compared with about 47% in the early 1970s. Many dietary factors have been proposed to contribute to the US obesity epidemic, including the percentage of energy intake from fat, carbohydrate and protein; glycemic index; fruit a...

  8. Ground Energy Balance For Shallow Geothermal Systems

    NASA Astrophysics Data System (ADS)

    Bayer, P.; Rivera, J.

    2015-12-01

    Vertical borehole heat exchangers (BHE) represent the most common applications by far in the field of shallow geothermal energy. They are typically operated for decades for energy extraction from the top 400 m of the subsurface. During this lifetime, thermal anomalies are generated in the ground and surface-near aquifers. These anomalies often grow over the years and compromise the overall performance of the geothermal system. As a basis for prediction and control of the developing energy imbalance in the ground, the focus is often set on the ground temperatures. This is reflected, for instance, in regulative temperature thresholds. As an alternative to temperature, we examine the temporal and spatial variability of heat fluxes and power sources during geothermal heat pump operation. The underlying idea is that knowledge of the primary heat sources is fundamental for the control of ground temperature evolution. For analysis of heat fluxes, an analytical framework for BHE simulation based on Kelvin's line source is re-formulated. This is applied to a synthetic study and for modelling a long-term application in the field. Our results show that during early operation phase, energy is extracted mainly from the underground. Local depletion at the borehole enhances the vertical fluxes with the relative contribution from the bottom reaching a limit of 24 % of the total power demand. The relative contribution from the ground surface becomes dominant for Fourier numbers larger than 0.13. For the full life cycle, vertical heat flux from the ground surface dominates the basal heat flux towards the BHE and it provides about two thirds of the demanded power. Finally, we reveal that the time for ground energy recovery after BHE shutdown may be longer than what is expected from simulated temperature trends.

  9. Measurement of balance function and community participation in stroke survivors.

    PubMed

    Ahn, Sinae

    2016-08-01

    [Purpose] This study aimed to investigate the relationship between balance function and community participation in stroke survivors. [Subjects and Methods] Sixty-three patients diagnosed with hemiparetic stroke participated in this study (36 males, 27 females, aged 58.6 ± 15.2 years). The participants were assessed for balance function and their level of participation in the community, using activity card sorting and the Berg Balance Scale. A regression analysis was used to identify the influence of balance function on instrumental activities of daily living and leisure and social activities. [Results] The results of the regression analysis indicated that balance function measured by using the Berg Balance Scale affected community participation of patients with hemiparetic stroke. Participation in instrumental activities of daily living and leisure and social activities was affected by balance function. [Conclusion] This study provides useful information for designing efficient programs and identifying their effectiveness for enhancement of community participation in stroke survivors.

  10. Development of Energy Balances for the State of California

    SciTech Connect

    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.

  11. Confinement time and energy balance in the CTX spheromak

    SciTech Connect

    Barnes, C.W.; Henins, I.; Hoida, H.W.; Jarboe, T.R.

    1984-01-01

    The multipoint Thomson scattering diagnostic on CTX allows measurement of electron plasma pressure. The pressure correlates well with the poloidal flux function. Analysis using equilibrium models allows the (..beta..)/sub vol/ to be calculated from over 100 Thomson scattering profiles taken under standard conditions of spheromak operation where the plasma parameters vary widely within the discharge. The calculated tau/sub E/ increases with central core temperature and with density. The global magnetic energy decay time tau/sub B/2 is consistent with Spitzer-Harm resistivity, but with an anomaly factor of 2 to 4 which may decrease at small ratios of B/n. The n tau/sub E/ product reaches 4 x 10/sup 9/ s cm/sup -3/ during the hottest part of the discharge. A zero-dimensional energy balance code, which accurately includes all the major atomic physics processes and whose parameters have been constrained by comparision to experimental data, is used to identify the causes of energy loss that contribute to the observed confinement time. The most important power loss is that needed to replace the particles being lost and to maintain the constant density of the plateau.

  12. Measuring pictorial balance perception at first glance using Japanese calligraphy

    PubMed Central

    Gershoni, Sharon; Hochstein, Shaul

    2011-01-01

    According to art theory, pictorial balance acts to unify picture elements into a cohesive composition. For asymmetrical compositions, balancing elements is thought to be similar to balancing mechanical weights in a framework of symmetry axes. Assessment of preference for balance (APB), based on the symmetry-axes framework suggested in Arnheim R, 1974 Art and Visual Perception: A Psychology of the Creative Eye (Berkeley, CA: University of California Press), successfully matched subject balance ratings of images of geometrical shapes over unlimited viewing time. We now examine pictorial balance perception of Japanese calligraphy during first fixation, isolated from later cognitive processes, comparing APB measures with results from balance-rating and comparison tasks. Results show high between-task correlation, but low correlation with APB. We repeated the rating task, expanding the image set to include five rotations of each image, comparing balance perception of artist and novice participant groups. Rotation has no effect on APB balance computation but dramatically affects balance rating, especially for art experts. We analyze the variety of rotation effects and suggest that, rather than depending on element size and position relative to symmetry axes, first fixation balance processing derives from global processes such as grouping of lines and shapes, object recognition, preference for horizontal and vertical elements, closure, and completion, enhanced by vertical symmetry. PMID:23145242

  13. Evaluation of surface energy and radiation balance systems for FIFE

    NASA Technical Reports Server (NTRS)

    Fritschen, Leo J.; Qian, Ping

    1988-01-01

    The energy balance and radiation balance components were determined at six sites during the First International Satellite Land Surface Climatology Project Field Experiment (FIFE) conducted south of Manhattan, Kansas during the summer of 1987. The objectives were: to determine the effect of slope and aspect, throughout a growing season, on the magnitude of the surface energy balance fluxes as determined by the Energy Balance Method (EBM); to investigate the calculation of the soil heat flux density at the surface as calculated from the heat capacity and the thermal conductivity equations; and to evaluate the performance of the Surface Energy and Radiation Balance System (SERBS). A total of 17 variables were monitored at each site. They included net, solar (up and down), total hemispherical (up and down), and diffuse radiation, soil temperature and heat flux density, air and wet bulb temperature gradients, wind speed and direction, and precipitation. A preliminary analysis of the data, for the season, indicate that variables including net radiation, air temperature, vapor pressure, and wind speed were quite similar at the sites even though the sites were as much as 16 km apart and represented four cardinal slopes and the top of a ridge.

  14. Surface-Parallel Sensor Orientation for Assessing Energy Balance Components on Mountain Slopes

    NASA Astrophysics Data System (ADS)

    Serrano-Ortiz, P.; Sánchez-Cañete, E. P.; Olmo, F. J.; Metzger, S.; Pérez-Priego, O.; Carrara, A.; Alados-Arboledas, L.; Kowalski, A. S.

    2016-03-01

    The consistency of eddy-covariance measurements is often evaluated in terms of the degree of energy balance closure. Even over sloping terrain, instrumentation for measuring energy balance components is commonly installed horizontally, i.e. perpendicular to the geo-potential gradient. Subsequently, turbulent fluxes of sensible and latent heat are rotated perpendicular to the mean streamlines using tilt-correction algorithms. However, net radiation (Rn) and soil heat fluxes ( G) are treated differently, and typically only Rn is corrected to account for slope. With an applied case study, we show and argue several advantages of installing sensors surface-parallel to measure surface-normal Rn and G. For a 17 % south-west-facing slope, our results show that horizontal installation results in hysteresis in the energy balance closure and errors of up to 25 %. Finally, we propose an approximation to estimate the surface-normal Rn, when only vertical Rn measurements are available.

  15. Meteorology Of The Clark Atlanta University Local Energy Balance Module

    NASA Astrophysics Data System (ADS)

    Mandock, R. L.; Mills, I.; Paxton, J. N.

    2005-05-01

    The Earth System Science Program (ESSP) at Clark Atlanta University has developed an instructional module to study energy balance at the air/land and air/sea interfaces. A graphical user interface (GUI) has been developed which is used to model each of the components (net radiation, sensible and latent heat fluxes, ground heat flux, storage, anthropomorphic, and residual) necessary to understand the partitioning of energy at the air/land and air/water interfaces. The energy balance diagram consists of sky elements (sun, moon, clouds), a line representing the air/land or water/land interface, and arrows which indicate magnitude and direction of each of the energy fluxes. The storage component is represented as a box when present. The energy balance model has been applied to numerous (33 at present) scenarios which vary by (1) climate or microclimate, (2) day and night, (2) cloudiness and sunshine, (3) windy and calm, (4) land or water surface, and (5) freezing and non-freezing temperatures. The model is available in 2 levels of rigor: (1) an elementary level (Level I), and (2) and advanced level (Level II). In the Level I model only fixed arrow lengths (e.g., zero, 1/4, 1/2, 3/4, 1) are available to express flux magnitude. This allows a qualitative illustration of the energy balance components. The Level II model requires the student to calculate arrow magnitudes and directions from diffusion, evaporation, radiative transfer, and energy storage equations. The module incorporates not only the energy balance model, but also a protocol by which meteorological observations from the ESSP's rooftop laboratory, the AEMN (Georgia Automated Environmental Monitoring Network), and other online resources. The completed module is designed to serve two audiences: (1) undergraduate introductory science classes and grades 8-12, and (2) upper-division science and engineering classes.

  16. Introducing the Balanced Scorecard: Creating Metrics to Measure Performance

    ERIC Educational Resources Information Center

    Gumbus, Andra

    2005-01-01

    This experiential exercise presents the concept of the Balanced Scorecard (BSC) and applies it in a university setting. The Balanced Scorecard was developed 12 years ago and has grown in popularity and is used by more than 50% of the Fortune 500 companies as a performance measurement and strategic management tool. The BSC expands the traditional…

  17. Evapotranspiration: Mass balance measurements compared with flux estimation methods

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Evapotranspiration (ET) may be measured by mass balance methods and estimated by flux sensing methods. The mass balance methods are typically restricted in terms of the area that can be represented (e.g., surface area of weighing lysimeter (LYS) or equivalent representative area of neutron probe (NP...

  18. Remote sensing of global snowpack energy and mass balance: In-situ measurements on the snow of interior and Arctic Alaska

    NASA Technical Reports Server (NTRS)

    Benson, Carl S.

    1989-01-01

    Observations led to a study of the physical properties of snow and the processes which operate on it. These observations included microwave brightness temperatures in interior Alaska which revealed: (1) up to three times more variability from one cell (1/2 degree latitude x 1/2 degree longitude) to the next in winter than in summer (5 to 15 K in winter and about 5 K in summer); (2) the overall range of temperature from week to week is about seven times greater in winter than in summer; (3) the microwave brightness temperature is about 25 K less than air temperature during summer but 35 to 60 K less during winter; and (4) the presence of snow cover appears to contribute to increasing the difference between air temperature and brightness temperature. The role of irregular substrate under the snow in enhancing convection has been studied with particular attention to variations in snow cover on water surfaces and in forested regions. LANDSAT imagery has been obtained to prepare a classification of ground surface types of the area. The extreme conditions of the 1988 to 1989 winter are discussed with respect to comparing the microwave data sets from 1985, and before, up to the present. The use of the Mt. Wrangell area as aerial photogrammetric controls for glacier measurements is given attention.

  19. Heat storage in forest biomass improves energy balance closure

    NASA Astrophysics Data System (ADS)

    Lindroth, A.; Mölder, M.; Lagergren, F.

    2010-01-01

    Temperature measurements in trunks and branches in a mature ca. 100 years-old mixed pine and spruce forest in central Sweden were used to estimate the heat storage in the tree biomass. The estimated heat flux in the sample trees and data on biomass distributions were used to scale up to stand level biomass heat fluxes. The rate of change of sensible and latent heat storage in the air layer below the level of the flux measurements was estimated from air temperature and humidity profile measurements and soil heat flux was estimated from heat flux plates and soil temperature measurements. The fluxes of sensible and latent heat from the forest were measured with an eddy covariance system in a tower. The analysis was made for a two-month period in summer of 1995. The tree biomass heat flux was the largest of the estimated storage components and varied between 40 and -35 W m-2 on summer days with nice weather. Averaged over two months the diurnal maximum of total heat storage was 45 W m-2 and the minimum was -35 W m-2. The soil heat flux and the sensible heat storage in air were out of phase with the biomass flux and they reached maximum values that were about 75% of the maximum of the tree biomass heat storage. The energy balance closure improved significantly when the total heat storage was added to the turbulent fluxes. The slope of a regression line with sum of fluxes and storage as independent and net radiation as dependent variable, increased from 0.86 to 0.95 for half-hourly data and the scatter was also reduced. The most significant finding was, however, that during nights with strongly stable conditions when the sensible heat flux dropped to nearly zero, the total storage matched the net radiation very well. Another interesting result was that the mean energy imbalance started to increase when the Richardson number became more negative than ca. -0.1. In fact, the largest energy deficit occurred at maximum instability. Our conclusion is that eddy covariance

  20. Reconnoitering the effect of shallow groundwater on land surface temperature and surface energy balance using MODIS and SEBS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The possibility of observing shallow groundwater depth and areal extent using satellite measurements can support groundwater models and vast irrigation systems management. Besides, these measurements help to integrate groundwater effects on surface energy balance within land surface models and clima...

  1. Dcf1 regulates neuropeptide expression and maintains energy balance.

    PubMed

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

    2017-04-01

    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.

  2. Intergenerational Energy Balance Interventions: A Systematic Literature Review

    ERIC Educational Resources Information Center

    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…

  3. Directed energy deflection laboratory measurements

    NASA Astrophysics Data System (ADS)

    Brashears, Travis; Lubin, Phillip; Hughes, Gary B.; Meinhold, Peter; Suen, Jonathan; Batliner, Payton; Motta, Caio; Griswold, Janelle; Kangas, Miikka; Johansson, Isbella; Alnawakhtha, Yusuf; Prater, Kenyon; Lang, Alex; Madajian, Jonathan

    2015-09-01

    We report on laboratory studies of the effectiveness of directed energy planetary defense as a part of the DESTAR (Directed Energy System for Targeting of Asteroids and exploRation) program. DE-STAR [1][5][6] and DE-STARLITE [2][5][6] are directed energy "stand-off" and "stand-on" programs, respectively. These systems consist of a modular array of kilowatt-class lasers powered by photovoltaics, and are capable of heating a spot on the surface of an asteroid to the point of vaporization. Mass ejection, as a plume of evaporated material, creates a reactionary thrust capable of diverting the asteroid's orbit. In a series of papers, we have developed a theoretical basis and described numerical simulations for determining the thrust produced by material evaporating from the surface of an asteroid [1][2][3][4][5][6]. In the DE-STAR concept, the asteroid itself is used as the deflection "propellant". This study presents results of experiments designed to measure the thrust created by evaporation from a laser directed energy spot. We constructed a vacuum chamber to simulate space conditions, and installed a torsion balance that holds an "asteroid" sample. The sample is illuminated with a fiber array laser with flux levels up to 60 MW/m2 which allows us to simulate a mission level flux but on a small scale. We use a separate laser as well as a position sensitive centroid detector to readout the angular motion of the torsion balance and can thus determine the thrust. We compare the measured thrust to the models. Our theoretical models indicate a coupling coefficient well in excess of 100 μN/Woptical, though we assume a more conservative value of 80 μN/Woptical and then degrade this with an optical "encircled energy" efficiency of 0.75 to 60 μN/Woptical in our deflection modeling. Our measurements discussed here yield about 45 μN/Wabsorbed as a reasonable lower limit to the thrust per optical watt absorbed.

  4. Investigation of the Impacts of Measured and Calculated Radiation Balance Components on Evapotranspiration

    NASA Astrophysics Data System (ADS)

    Akataş, Nilcan; Yeşilköy, Serhan; Şaylan, Levent

    2016-04-01

    Determination of surface energy balance over agricultural lands plays a crucial role to better investigation of sustainable agriculture and food security which are related to evapotranspiration. Surface energy balance components that include net shortwave and longwave radiation depend on surface conditions like surface albedo and climate of a region. Surface albedo is ratio between reflected longwave radiation and incoming shortwave radiation. There are many different crops in agriculture ecosystem. Thus, surface energy balance components vary by vegetation surfaces. Net radiation is most important component of surface energy balance which is difference between net shortwave and longwave radiation. These are calculated by commonly used equations and applied to the FAO Penman& Monteith equation using meteorological stations' data located in cities. However, there are differences between urban areas and agricultural ecosystems. This situation causes to the calculation errors. In this research, it is aimed to investigate the changes between estimated and measured surface energy balance components which are estimated by meteorological stations' data in the urban area and measurements from an rural area over winter wheat surface 2014-2015 growing season in Thrace Region located in the Northwestern part of Turkey, Kırklareli city. Keywords: Surface energy balance, winter wheat, FAO Penman-Monteith, Kırklareli/Turkey

  5. Dynamical horizons: energy, angular momentum, fluxes, and balance laws.

    PubMed

    Ashtekar, Abhay; Krishnan, Badri

    2002-12-23

    Dynamical horizons are considered in full, nonlinear general relativity. Expressions of fluxes of energy and angular momentum carried by gravitational waves across these horizons are obtained. Fluxes are local, the energy flux is positive, and change in the horizon area is related to these fluxes. The flux formulas also give rise to balance laws analogous to the ones obtained by Bondi and Sachs at null infinity and provide generalizations of the first and second laws of black-hole mechanics.

  6. Phenotypic clines, energy balances and ecological responses to climate change.

    PubMed

    Buckley, Lauren B; Nufio, César R; Kingsolver, Joel G

    2014-01-01

    The Metabolic Theory of Ecology has renewed interest in using energetics to scale across levels of ecological organization. Can scaling from individual phenotypes to population dynamics provides insight into why species have shifted their phenologies, abundances and distributions idiosyncratically in response to recent climate change? We consider how the energetic implications of phenotypes may scale to understand population and species level responses to climate change using four focal grasshopper species along an elevation gradient in Colorado. We use a biophysical model to translate phenotypes and environmental conditions into estimates of body temperatures. We measure thermal tolerances and preferences and metabolic rates to assess rates of energy use and acquisition. Body mass declines along the elevation gradient for all species, but mass-specific metabolic rates increases only modestly. We find interspecific differences in both overall thermal tolerances and preferences and in the variation of these metrics along the elevation gradient. The more dispersive species exhibit significantly higher thermal tolerance and preference consistent with much of their range spanning hot, low elevation areas. When integrating these metrics to consider metabolic constraints, we find that energetic costs decrease along the elevation gradient due to decreasing body size and temperature. Opportunities for energy acquisition, as reflected by the proportion of time that falls within a grasshopper's thermal tolerance range, peak at mid elevations. We discuss methods for translating these energetic metrics into population dynamics. Quantifying energy balances and allocation offers a viable approach for predicting how populations will respond to climate change and the consequences for species composed of populations that may be locally adapted.

  7. Energy balance framework for Net Zero Energy buildings

    EPA Science Inventory

    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...

  8. An Analysis of Turbulent Heat Fluxes and the Energy Balance During the REFLEX Campaign

    NASA Astrophysics Data System (ADS)

    Tol, Christiaan van der; Timmermans, Wim; Corbari, Chiara; Carrara, Arnaud; Timmermans, Joris; Su, Zhongbo

    2015-12-01

    Three eddy covariance stations were installed at the Barrax experimental farm during the Land-Atmosphere Exchanges (REFLEX) airborne training and measurement campaign to provide ground truth data of energy balance fluxes and vertical temperature and wind profiles. The energy balance closure ratio (EBR) was 105% for a homogeneous camelina site, 86% at a sparse reforestation site, and 73% for a vineyard. We hypothesize that the lower closure in the last site was related to the limited fetch. Incorporating a vertical gradient of soil thermal properties decreased the RMSE of the energy balance at the camelina site by 16 W m-2. At the camelina site, eddy covariance estimates of sensible and latent heat fluxes could be reproduced well using mean vertical profiles of wind and temperature, provided that the Monin-Obukhov length is known. Measured surface temperature and sensible heat fluxes suggested high excess resistance for heat (kB-1 = 17).

  9. An Analysis of Turbulent Heat Fluxes and the Energy Balance During the REFLEX Campaign

    NASA Astrophysics Data System (ADS)

    van der Tol, Christiaan; Timmermans, Wim; Corbari, Chiara; Carrara, Arnaud; Timmermans, Joris; Su, Zhongbo

    2015-12-01

    Three eddy covariance stations were installed at the Barrax experimental farm during the Land-Atmosphere Exchanges (REFLEX) airborne training and measurement campaign to provide ground truth data of energy balance fluxes and vertical temperature and wind profiles. The energy balance closure ratio (EBR) was 105% for a homogeneous camelina site, 86% at a sparse reforestation site, and 73% for a vineyard. We hypothesize that the lower closure in the last site was related to the limited fetch. Incorporating a vertical gradient of soil thermal properties decreased the RMSE of the energy balance at the camelina site by 16 W m-2. At the camelina site, eddy covariance estimates of sensible and latent heat fluxes could be reproduced well using mean vertical profiles of wind and temperature, provided that the Monin—Obukhov length is known. Measured surface temperature and sensible heat fluxes suggested high excess resistance for heat (kB-1 = 17).

  10. Evaluation of surface energy and radiation balance systems on the Konza Prairie

    NASA Technical Reports Server (NTRS)

    Fritschen, Leo J.

    1987-01-01

    Four Surface Energy and Radiation Balance Systems (SERBS) were installed and operated for two weeks in Kansas during July of 1986. Surface energy and radiation balances were investigated on six sites on the Konza Prairie about 3 km south of Manhattan, Kansas. Measurements were made to allow the computation of these radiation components: total solar and diffuse radiation, reflected solar radiation, net radiation, and longwave radiation upward and downward. Measurements were made to allow the computation of the sensible and latent heat fluxes by the Bowen ratio method using differential psychrometers on automatic exchange mechanisms. The report includes a description of the experimental sites, data acquisition systems and sensors, data acquisitions system operating instructions, and software used for data acquisition and analysis. In addition, data listings and plots of the energy balance components for all days and systems are given.

  11. Low protein diets produce divergent effects on energy balance

    PubMed Central

    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

  12. Report Calls for Balancing Energy Security, Energy Equity, and Environmental Concerns

    NASA Astrophysics Data System (ADS)

    Showstack, Randy

    2014-12-01

    Balancing the sometimes conflicting needs for energy security, energy equity, and environmental sustainability—including trying to limit average global temperature increases—can be a daunting task for countries. A new report focuses on the challenges and potential pathways to achieving this energy "trilemma" of meeting energy and environmental needs.

  13. Energy balance closure on a winter wheat stand: comparing the eddy covariance technique with the soil water balance method

    NASA Astrophysics Data System (ADS)

    Imukova, K.; Ingwersen, J.; Hevart, M.; Streck, T.

    2016-01-01

    The energy balance of eddy covariance (EC) flux data is typically not closed. The nature of the gap is usually not known, which hampers using EC data to parameterize and test models. In the present study we cross-checked the evapotranspiration data obtained with the EC method (ETEC) against ET rates measured with the soil water balance method (ETWB) at winter wheat stands in southwest Germany. During the growing seasons 2012 and 2013, we continuously measured, in a half-hourly resolution, latent heat (LE) and sensible (H) heat fluxes using the EC technique. Measured fluxes were adjusted with either the Bowen-ratio (BR), H or LE post-closure method. ETWB was estimated based on rainfall, seepage and soil water storage measurements. The soil water storage term was determined at sixteen locations within the footprint of an EC station, by measuring the soil water content down to a soil depth of 1.5 m. In the second year, the volumetric soil water content was additionally continuously measured in 15 min resolution in 10 cm intervals down to 90 cm depth with sixteen capacitance soil moisture sensors. During the 2012 growing season, the H post-closed LE flux data (ETEC = 3.4 ± 0.6 mm day-1) corresponded closest with the result of the WB method (3.3 ± 0.3 mm day-1). ETEC adjusted by the BR (4.1 ± 0.6 mm day-1) or LE (4.9 ± 0.9 mm day-1) post-closure method were higher than the ETWB by 24 and 48 %, respectively. In 2013, ETWB was in best agreement with ETEC adjusted with the H post-closure method during the periods with low amount of rain and seepage. During these periods the BR and LE post-closure methods overestimated ET by about 46 and 70 %, respectively. During a period with high and frequent rainfalls, ETWB was in-between ETEC adjusted by H and BR post-closure methods. We conclude that, at most observation periods on our site, LE is not a major component of the energy balance gap. Our results indicate that the energy balance gap is made up by

  14. Dual strain gage balance system for measuring light loads

    NASA Technical Reports Server (NTRS)

    Roberts, Paul W. (Inventor)

    1991-01-01

    A dual strain gage balance system for measuring normal and axial forces and pitching moment of a metric airfoil model imparted by aerodynamic loads applied to the airfoil model during wind tunnel testing includes a pair of non-metric panels being rigidly connected to and extending towards each other from opposite sides of the wind tunnel, and a pair of strain gage balances, each connected to one of the non-metric panels and to one of the opposite ends of the metric airfoil model for mounting the metric airfoil model between the pair of non-metric panels. Each strain gage balance has a first measuring section for mounting a first strain gage bridge for measuring normal force and pitching moment and a second measuring section for mounting a second strain gage bridge for measuring axial force.

  15. Prediction of energy balance in high yielding dairy cows with test-day information.

    PubMed

    Heuer, C; Van Straalen, W M; Schukken, Y H; Dirkzwager, A; Noordhuizen, T M

    2001-02-01

    This study used a previously developed model to predict herd mean energy balance of the first 12 wk of lactation from test-day information. The predictions were compared with calculated energy balance based on feed analysis and to changes in body weight. Seven independent feeding trials including 43 diets (519 lactations, 254 cows; 1987 to 1996) were used. Conventional diets were discriminated from nonconventional diets by significant differences between mean calculated energy balance of subtrial diets versus control diets. The total difference between group means of predicted minus calculated energy balance was positive throughout the observed lactation period. It was lowest (5 to 9 MJ of net energy for lactation) during negative energy balance of the conventional diets in wk 2 to 7 when 18 to 50% of the total difference was due to random variation. Because of this difference, both predicted and calculated energy balances were compared to body weight change as a reference for true energy balance. Body weight change was adjusted for rumen fill. While calculated energy balance tended to be negative at times when cows gained weight, predicted energy balance was positive. Cows fed nonconventional diets gained weight, while calculated energy balance was extremely negative, whereas predicted energy balance based on test-day information was positive. We concluded that the prediction difference was relatively small when standard rations were used, and that nonconventional rations biased predicted energy balance to a lesser extent than calculated energy balance. Estimating energy balance based on test-day information appears feasible.

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

    PubMed

    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.

  17. Energy intake, physical activity, energy balance, and cancer: epidemiologic evidence.

    PubMed

    Pan, Sai Yi; DesMeules, Marie

    2009-01-01

    Energy intake, physical activity, and obesity are modifiable lifestyle factors. This chapter reviews and summarizes the epidemiologic evidence on the relation of energy intake, physical activity, and obesity to cancer. High energy intake may increase the risk of cancers of colon-rectum, prostate (especially advanced prostate cancer), and breast. However, because physical activity, body size, and metabolic efficiency are highly related to total energy intake and expenditure, it is difficult to assess the independent effect of energy intake on cancer risk. There are sufficient evidences to support a role of physical activity in preventing cancers of the colon and breast, whereas the association is stronger in men than in women for colon cancer and in postmenopausal than in premenopausal women for breast cancer. The evidence also suggests that physical activity likely reduces the risk of cancers of endometrium, lung, and prostate (to a lesser extent). On the other hand, there is little or no evidence that the risk of rectal cancer is related to physical activity, whereas the results have been inconsistent regarding the association between physical activity and the risks of cancers of pancreas, ovary and kidney. Epidemiologic studies provide sufficient evidence that obesity is a risk factor for both cancer incidence and mortality. The evidence supports strong links of obesity with the risk of cancers of the colon, rectum, breast (in postmenopausal women), endometrium, kidney (renal cell), and adenocarcinoma of the esophagus. Epidemiologic evidence also indicates that obesity is probably related to cancers of the pancreas, liver, and gallbladder, and aggressive prostate cancer, while it seems that obesity is not associated with lung cancer. The role of obesity in other cancer risks is unclear.

  18. Energy and mass balances related to climate change and remediation.

    PubMed

    Lueking, Angela D; Cole, Milton W

    2017-07-15

    The goal of this paper is to provide a forum for a broad interdisciplinary group of scientists and engineers to see how concepts of climate change, energy, and carbon remediation strategies are related to quite basic scientific principles. A secondary goal is to show relationships between general concepts in traditional science and engineering fields and to show how they are relevant to broader environmental concepts. This paper revisits Fourier's early mathematical derivation of the average temperature of the Earth from first principles, i.e. an energy balance common to chemical and environmental engineering. The work then uses the concept of mass balance to critically discuss various carbon remediation strategies. The work is of interest to traditional scientists/engineers, but also it is potentially useful as an educational document in advanced undergraduate science or engineering classes.

  19. Control and Size Energy Storage for Managing Energy balance of Variable Generation Resources

    SciTech Connect

    Ke, Xinda; Lu, Ning; Jin, Chunlian

    2015-01-01

    This paper presents control algorithms and sizing strategies for using energy storage to manage energy balance for variable generation resources. The control objective is to minimize the hourly generation imbalance between the actual and the scheduled generation of the wind farm. Three control algorithms are compared: tracking power imbalance, post-compensation, and pre-compensation. Measurement data from a wind farm located in South-central Washington State are used in the study. The results show that tracking power imbalance yields the best performance by keeping the hourly energy imbalances zero. However, the energy storage system (ESS) will be significantly oversized. Post-compensation reduces power rating of the ESS but the hourly imbalance may not be kept as zero when large and long-lasting energy imbalances occur. A linear regression forecasting algorithm is developed for the pre-compensation algorithm to pre-charge or pre-discharge the ESS based on predicted energy imbalances. The performance comparison shows that the pre-compensation method significantly reduces the size of the ESS while maintaining satisfactory performance.

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

    NASA Technical Reports Server (NTRS)

    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.

  1. An update on Earth's energy balance in light of the latest global observations

    NASA Astrophysics Data System (ADS)

    Stephens, Graeme L.; Li, Juilin; Wild, Martin; Clayson, Carol Anne; Loeb, Norman; Kato, Seiji; L'Ecuyer, Tristan; Stackhouse, Paul W.; Lebsock, Matthew; Andrews, Timothy

    2012-10-01

    Climate change is governed by changes to the global energy balance. At the top of the atmosphere, this balance is monitored globally by satellite sensors that provide measurements of energy flowing to and from Earth. By contrast, observations at the surface are limited mostly to land areas. As a result, the global balance of energy fluxes within the atmosphere or at Earth's surface cannot be derived directly from measured fluxes, and is therefore uncertain. This lack of precise knowledge of surface energy fluxes profoundly affects our ability to understand how Earth's climate responds to increasing concentrations of greenhouse gases. In light of compilations of up-to-date surface and satellite data, the surface energy balance needs to be revised. Specifically, the longwave radiation received at the surface is estimated to be significantly larger, by between 10 and 17 Wm-2, than earlier model-based estimates. Moreover, the latest satellite observations of global precipitation indicate that more precipitation is generated than previously thought. This additional precipitation is sustained by more energy leaving the surface by evaporation -- that is, in the form of latent heat flux -- and thereby offsets much of the increase in longwave flux to the surface.

  2. Albedo, internal heat, and energy balance of Jupiter, preliminary results of the Voyager infrared investigation

    NASA Technical Reports Server (NTRS)

    Hanel, R. A.; Conrath, B. J.; Herath, L. W.; Kunde, V. G.; Pirraglia, J. A.

    1980-01-01

    The in flight calibration of the radiometer and the Michelson interferometer of the Voyager 1 infrared instrument is discussed. The calibrated full disk measurements are applied to derive values of the albedo, the thermal emission and the global energy balance of Jupiter.

  3. Irreversibility in energy processes: Non-dimensional quantification and balance

    NASA Astrophysics Data System (ADS)

    Pons, Michel

    2004-06-01

    The concept of thermodynamic efficiency (ratio of real cycle efficiency by Carnot efficiency) is well-known. The concept of numbers of entropy-production and of exergy-loss proposed by A. Bejan are also known, but rarely used. The present study firstly evidences that these two last numbers are actually identical, thus being a common number of irreversibility, independent of the method used for obtaining it. The study also evidences a non-dimensional irreversibility balance that applies to any energy conversion process. This balance correlates the thermodynamic efficiency of a whole process (which in most cases equals the exergetic efficiency) and the numbers of irreversibility of the different components or sub-processes involved in this process. Moreover, the basic additivity of entropy-productions and exergy-losses is maintained in this balance. This balance applies to the basic cycles (heat-engines, refrigerators, heat-pumps and heat-transformers), either work- or heat-powered. It also applies to more complex cycles (heat-powered cycles consuming electricity, four-temperature heat-powered cycles, cogeneration processes), thus giving a robust framework for analyzing these cycles.

  4. Gender Differences in Insulin Resistance, Body Composition, and Energy Balance

    PubMed Central

    Geer, Eliza B.; Shen, Wei

    2010-01-01

    Background Men and women differ substantially in regard to degrees of insulin resistance, body composition, and energy balance. Adipose tissue distribution, in particular the presence of elevated visceral and hepatic adiposity, plays a central role in the development of insulin resistance and obesity-related complications. Objective This review summarizes published data on gender differences in insulin resistance, body composition, and energy balance, to provide insight into novel gender-specific avenues of research as well as gender-tailored treatments of insulin resistance, visceral adiposity, and obesity. Methods English-language articles were identified from searches of the PubMed database through November 2008, and by reviewing the references cited in these reports. Searches included combinations of the following terms: gender, sex, insulin resistance, body composition, energy balance, and hepatic adipose tissue. Results For a given body mass index, men were reported to have more lean mass, women to have higher adiposity. Men were also found to have more visceral and hepatic adipose tissue, whereas women had more peripheral or subcutaneous adipose tissue. These differences, as well as differences in sex hormones and adipokines, may contribute to a more insulin-sensitive environment in women than in men. When normalized to kilograms of lean body mass, men and women had similar resting energy expenditure, but physical energy expenditure was more closely related to percent body fat in men than in women. Conclusion Greater amounts of visceral and hepatic adipose tissue, in conjunction with the lack of a possible protective effect of estrogen, may be related to higher insulin resistance in men compared with women. PMID:19318219

  5. Energy balance regulation by thyroid hormones at central level.

    PubMed

    López, Miguel; Alvarez, Clara V; Nogueiras, Rubén; Diéguez, Carlos

    2013-07-01

    Classically, medical textbooks taught that most effects of thyroid hormones (THs) on energy homeostasis are directly exerted in peripheral tissues. However, current evidence is changing (and challenging) our perspective about the role of THs from a 'peripheral' to a 'central' vision, implying that they affect food intake, energy expenditure, and metabolism by acting, to a large extent, at the central level. Interestingly, effects of THs are interrelated with global energy sensors in the central nervous system (CNS), such as uncoupling protein 2 (UCP2), AMP-activated protein kinase (AMPK; the 'AMPK-BAT axis'), and mechanistic target of rapamycin (mTOR). Here, we review what is currently known about THs and their regulation of energy balance and metabolism in both peripheral and central tissues.

  6. Balance or bias: building an equitable energy budget

    SciTech Connect

    DeVaul, D.

    1982-01-01

    The findings of two major studies on the effects of high energy prices are summarized in an effort to develop reliable data for purposes of explanation. The first study, Regional Energy, reviews what is known about the relationship between energy price increases and national economic performance in the 1970s, and details the regional, state, and local effects. The second study, The Impact of Federal Energy Policies, analyzes the effect of federal policies and programs since World War II on the price and availability of energy in different sections of the country. An analysis of past energy policies reveals a strong bias toward oil- and gas-producing areas that is out of balance with national energy needs in the 1980s. Current federal policies continue those biases to the detriment of energy-dependent areas, particularly those in the Northeast and Midwest. The monograph concludes with a series of policy options designed to correct the imbalance in the federal energy budget. 2 figures, 5 tables.

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

    PubMed

    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. Influence of topiramate in the regulation of energy balance.

    PubMed

    Richard, D; Ferland, J; Lalonde, J; Samson, P; Deshaies, Y

    2000-10-01

    Topiramate (TPM) is a novel neurotherapeutic agent currently indicated for the treatment of epilepsy and undergoing development for other central nervous system indications including neuropathic pain, bipolar disorder, and migraine prophylaxis. TPM is synthesized from D-fructose and contains a sulfamate moiety that is essential for its pharmacologic activity. TPM has been observed to significantly reduce body weight in patients treated for seizure, which has prompted the realization of preclinical studies to characterize the effects of TPM in the regulation of energy balance. Studies carried out in various strains of rats have provided good evidence for the ability of TPM to blunt energy deposition. Body composition analyses from rat trials have demonstrated that TPM inhibits fat deposition while reducing the activity of lipoprotein lipase (LPL) in various white adipose tissue depots. High doses of TPM (likely above the therapeutic dose range) have also been observed to reduce protein gain without catabolic effects. Although TPM cannot be described as a potent anorectic agent, it seems to have the ability to reduce food intake; significant reductions in food intake have been observed in female obese (fa/fa) Zucker rats and in female Wistar rats. TPM can also reduce energy deposition in the absence of alterations in food intake. This effect has been clearly emphasized in female lean (Fa/?) Zucker rats. In female Sprague-Dawley rats, TPM also increased energy expenditure and it has been observed to increase LPL activity in brown adipose tissue, which could indicate that TPM has the ability to enhance regulatory thermogenesis. In addition, TPM stimulates LPL activity in skeletal muscles, further emphasizing its potential to promote substrate oxidation. The mechanisms whereby TPM affects the regulation of energy balance have yet to be understood. TPM represents an antiepileptic drug (AED) with complex biochemical/pharmacologic actions. Its negative effects on energy

  9. Leptin: at the crossroads of energy balance and systemic inflammation

    PubMed Central

    Steiner, Alexandre A.; Romanovsky, Andrej A.

    2007-01-01

    In addition to playing a central role in energy homeostasis, leptin is also an important player in the inflammatory response. Systemic inflammation is accompanied by fever (less severe cases) or hypothermia (more severe cases). In leptin-irresponsive mutants, the hypothermia of systemic inflammation is exaggerated, presumably due to the enhanced production and cryogenic action of tumor necrosis factor (TNF)-α. Mechanisms that exaggerate hypothermia can also attenuate fever, particularly in a cool environment. Another common manifestation of systemic inflammation is behavioral depression. Along with the production of interleukin (IL)-1β, this manifestation is exaggerated in leptin-irresponsive mutants. The enhanced production of TNF-α and IL-1β may be due, at least in part, to insufficient activation of the anti-inflammatory hypothalamo-pituitary-adrenal axis by immune stimuli in the absence of leptin signaling. In experimental animals and humans that are responsive to leptin, suppression of leptin production under conditions of negative energy balance (e.g., fasting) can exaggerate both hypothermia and behavioral depression. Since these manifestations aid energy conservation, exaggeration of these manifestations under conditions of negative energy balance is likely to be beneficial. PMID:17275915

  10. Brain regulation of energy balance and body weight.

    PubMed

    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.

  11. Energy balance for analysis of complex metabolic networks.

    PubMed Central

    Beard, Daniel A; Liang, Shou-dan; Qian, Hong

    2002-01-01

    Predicting behavior of large-scale biochemical networks represents one of the greatest challenges of bioinformatics and computational biology. Computational tools for predicting fluxes in biochemical networks are applied in the fields of integrated and systems biology, bioinformatics, and genomics, and to aid in drug discovery and identification of potential drug targets. Approaches, such as flux balance analysis (FBA), that account for the known stoichiometry of the reaction network while avoiding implementation of detailed reaction kinetics are promising tools for the analysis of large complex networks. Here we introduce energy balance analysis (EBA)--the theory and methodology for enforcing the laws of thermodynamics in such simulations--making the results more physically realistic and revealing greater insight into the regulatory and control mechanisms operating in complex large-scale systems. We show that EBA eliminates thermodynamically infeasible results associated with FBA. PMID:12080101

  12. Distributed energy balance modeling of South Cascade Glacier, Washington and assessment of model uncertainty

    USGS Publications Warehouse

    Anslow, Faron S.; Hostetler, S.; Bidlake, W.R.; Clark, P.U.

    2008-01-01

    We have developed a physically based, distributed surface energy balance model to simulate glacier mass balance under meteorological and climatological forcing. Here we apply the model to estimate summer ablation on South Cascade Glacier, Washington, for the 2004 and 2005 mass balance seasons. To arrive at optimal mass balance simulations, we investigate and quantify model uncertainty associated with selecting from a range of physical parameter values that are not commonly measured in glaciological mass balance field studies. We optimize the performance of the model by varying values for atmospheric transmissivity, the albedo of surrounding topography, precipitation-elevation lapse rate, surface roughness for turbulent exchange of momentum, and snow albedo aging coefficient. Of these the snow aging parameter and precipitation lapse rates have the greatest influence on the modeled ablation. We examined model sensitivity to varying parameters by performing an additional 103 realizations with parameters randomly chosen over a ??5% range centered about the optimum values. The best fit suite of model parameters yielded a net balance of -1.69??0.38 m water equivalent (WE) for the 2004 water year and -2.10??0.30 m WE up to 11 September 2005. The 2004 result is within 3% of the measured value. These simulations account for 91% and 93% of the variance in measured ablation for the respective years. Copyright 2008 by the American Geophysical Union.

  13. Seasonal Contrasts in the Surface Energy Balance of the Sahel

    SciTech Connect

    Miller, Ron; Slingo, A.; Barnard, James C.; Kassianov, Evgueni I.

    2009-03-14

    Over most of the world ocean, heating of the surface by sunlight is balanced predominately by evaporative cooling. Even over land, moisture for evaporation is available from vegetation or the soil reservoir. However, at the ARM Mobile Facility in Niamey, Niger, soil moisture is so depleted that evaporation makes a significant contribution to the surface energy balance only at the height of the rainy season, when precipitation has replenished the soil reservoir. Using observations at the Mobile Facility from late 2005 to early 2007, we describe how the surface balances radiative forcing. How the surface compensates time-averaged solar heating varies with seasonal changes in atmospheric water vapor, which modulates the greenhouse effect and the ability of the surface to radiate thermal energy directly to space. During the dry season, sunlight is balanced mainly by longwave radiation and the turbulent flux of sensible heat. The ability of longwave radiation to cool the surface drops after the onset of the West African summer monsoon, when moist, oceanic air flows onshore, increasing local column moisture and atmospheric opacity at these wavelengths. After the monsoon onset, but prior to significant rainfall, solar heating is compensated mainly by the sensible heat flux. During the rainy season, the magnitude of evaporation is initially controlled by the supply of moisture from precipitation. However, by the height of the rainy season, sufficient precipitation has accumulated at the surface that evaporation is related to the flux demanded by solar radiation, and radiative forcing of the surface is balanced comparably by the latent, sensible, and longwave fluxes. Radiative forcing of the surface also varies on a subseasonal time scale due to fluctuations in water vapor, clouds, and aerosol concentration. Except at the height of the rainy season, subseasonal forcing is balanced mainly by sensible heating and longwave anomalies. The efficacy of the sensible heat flux

  14. The energy balance of plasmoids in the solar atmosphere

    NASA Technical Reports Server (NTRS)

    Cargill, P. J.; Pneuman, G. W.

    1986-01-01

    The properties of an isolated magnetized plasmoid in a nonuniform magnetic field such as arises in stellar atmospheres are studied. The work of Pneuman and Cargill (1985) on the so-called melon-seed effect is extended to include an equation describing the energy balance, so giving a unified picture of the shape, motion, and energetics of the plasmoid. Three treatments of plasmoid energy balance are considered: (1) a polytropic law, (P = about N to the gamma); (2) one in which the plasmoid cools radiatively; and (3) one in which a heating function proportional to the local density balances the radiation. For a gamma = 4/3 polytrope the evolution is self-similar, so that the plasmoid maintains its shape as it moves out from the stellar surface. If gamma is less than 4/3, the final shape is a long thin cigar-shaped body, whereas if gamma is greater than or equal to 4/3, it ultimately becomes self-similar. In cases with radiation and also with heating, the ultimate shape of the plasmoid is determined by whether its gas or magnetic pressure dominate. The former is equivalent to the gamma-less-than-4/3 polytrope, and the latter to the gamma-greater-than-4/3 one. If radiation alone is present, the plasmoid cools rapidly and subsequently evolves self-similarly. If heating balances radiation initially, then the plasmoid heats up as it moves out, but, if the ratio of the transit of time of Alfven waves across it is much less than the radiative cooling time, it ultimately evolves as a gamma = 5/3 polytrope. In each case the plasmoid can be ejected to large distances (several radii) in a stellar atmosphere, for a reasonable choice of surface parameters.

  15. Reciprocal Compensation to Changes in Dietary Intake and Energy Expenditure within the Concept of Energy Balance123

    PubMed Central

    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 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. PMID:26374181

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

    PubMed Central

    Alexandrou, Athanasios; Tenbergen, Klaus; Adhikari, Diganta

    2013-01-01

    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.

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

    PubMed

    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.

  18. Role of Northern Lakes in Landscape Energy Balance

    NASA Astrophysics Data System (ADS)

    Rouse, W. R.; Oswald, C. J.; Spence, C.; Blanken, P. D.; Bussières, N.; Schertzer, W. M.; Duguay, C. R.; Binyamin, J.

    2004-05-01

    In the central Mackenzie River Valley of western Canada, from which most of the data used in this study are derived, there are about 32,370 lakes. For the specific study region used to determine the landscape energy balance, lakes comprise 37% of the landscape. They are classified as small (<1 km2), medium (1-100 km2) and large (>100 km2). The large lake is represented by the central portion of Great Slave Lake. The non-lake components of the landscape are divided into wetlands (8%) and uplands (55%). With such abundance, lakes are important features in regional climatic, meteorological and biogeochemical cycling. The purpose of this paper is to examine the regional role of lakes in the surface energy and water balance, to link this to the frequency-size distribution of lakes, and to cast some light on how the surface energy balance may influence regional climate and weather processes. Toward this end we employ recently-gathered data from northern lakes of various sizes, characterize their surface energy balances for both magnitude and temporal behavior of fluxes, and examine the impacts of combinations of various-size lakes and land-lake distributions on regional energy balances and evaporation cycles. The analysis is limited to the ice-free period. Net radiation was substantially greater over all water-dominated surfaces compared with uplands (U). Seasonal differences were 16% greater for wetlands (W), 25% greater for small (SL) and medium (ML) lakes and 73% greater for Great Slave Lake (LL). At maximum, the seasonal heat storage relative to net radiation was 6, 9, 26, 55 and 76 % for U, W, SL, ML and LL respectively. ML and LL are slow to warm in summer but their large cumulative heat storage near summer's end has a major impact on the regional energy balance, because this heat is available to feed convective heat fluxes in fall and early winter. The evaporation season for U, W, SL, ML and LL lasts for 19, 21, 22, 24 and 30 weeks respectively. The effects of

  19. Life cycle assessment of biofuels: energy and greenhouse gas balances.

    PubMed

    Gnansounou, E; Dauriat, A; Villegas, J; Panichelli, L

    2009-11-01

    The promotion of biofuels as energy for transportation in the industrialized countries is mainly driven by the perspective of oil depletion, the concerns about energy security and global warming. However due to sustainability constraints, biofuels will replace only 10 to 15% of fossil liquid fuels in the transport sector. Several governments have defined a minimum target of GHG emissions reduction for those biofuels that will be eligible to public incentives, for example a 35% emissions reduction in case of biofuels in Members States of the European Union. This article points out the significant biases in estimating GHG balances of biofuels stemming from modelling choices about system definition and boundaries, functional unit, reference systems and allocation methods. The extent to which these choices influence the results is investigated. After performing a comparison and constructive criticism of various modelling choices, the LCA of wheat-to-bioethanol is used as an illustrative case where bioethanol is blended with gasoline at various percentages (E5, E10 and E85). The performance of these substitution options is evaluated as well. The results show a large difference in the reduction of the GHG emissions with a high sensitivity to the following factors: the method used to allocate the impacts between the co-products, the type of reference systems, the choice of the functional unit and the type of blend. The authors come out with some recommendations for basing the estimation of energy and GHG balances of biofuels on principles such as transparency, consistency and accuracy.

  20. Primary cilia in energy balance signaling and metabolic disorder

    PubMed Central

    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 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. [BMB Reports 2015; 48(12): 647-654] PMID:26538252

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

    NASA Astrophysics Data System (ADS)

    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.

  2. Adipocytes as regulators of energy balance and glucose homeostasis

    PubMed Central

    Rosen, Evan D.; Spiegelman, Bruce M.

    2011-01-01

    Adipocytes have been studied with increasing intensity as a result of the emergence of obesity as a serious public health problem and the realization that adipose tissue serves as an integrator of various physiological pathways. In particular, their role in calorie storage makes adipocytes well suited to the regulation of energy balance. Adipose tissue also serves as a crucial integrator of glucose homeostasis. Knowledge of adipocyte biology is therefore crucial for understanding the pathophysiological basis of obesity and metabolic diseases such as type 2 diabetes. Furthermore, the rational manipulation of adipose physiology is a promising avenue for therapy of these conditions. PMID:17167472

  3. The Precession Index and a Nonlinear Energy Balance Climate Model

    NASA Technical Reports Server (NTRS)

    Rubincam, David

    2004-01-01

    A simple nonlinear energy balance climate model yields a precession index-like term in the temperature. Despite its importance in the geologic record, the precession index e sin (Omega)S, where e is the Earth's orbital eccentricity and (Omega)S is the Sun's perigee in the geocentric frame, is not present in the insolation at the top of the atmosphere. Hence there is no one-for-one mapping of 23,000 and 19,000 year periodicities from the insolation to the paleoclimate record; a nonlinear climate model is needed to produce these long periods. A nonlinear energy balance climate model with radiative terms of form T n, where T is surface temperature and n less than 1, does produce e sin (omega)S terms in temperature; the e sin (omega)S terms are called Seversmith psychroterms. Without feedback mechanisms, the model achieves extreme values of 0.64 K at the maximum orbital eccentricity of 0.06, cooling one hemisphere while simultaneously warming the other; the hemisphere over which perihelion occurs is the cooler. In other words, the nonlinear energy balance model produces long-term cooling in the northern hemisphere when the Sun's perihelion is near northern summer solstice and long-term warming in the northern hemisphere when the aphelion is near northern summer solstice. (This behavior is similar to the inertialess gray body which radiates like T 4, but the amplitude is much lower for the energy balance model because of its thermal inertia.) This seemingly paradoxical behavior works against the standard Milankovitch model, which requires cool northern summers (Sun far from Earth in northern summer) to build up northern ice sheets, so that if the standard model is correct it must be more efficient than previously thought. Alternatively, the new mechanism could possibly be dominant and indicate southern hemisphere control of the northern ice sheets, wherein the southern oceans undergo a long-term cooling when the Sun is far from the Earth during northern summer. The cold

  4. BALANCE

    DOEpatents

    Carmichael, H.

    1953-01-01

    A torsional-type analytical balance designed to arrive at its equilibrium point more quickly than previous balances is described. In order to prevent external heat sources creating air currents inside the balance casing that would reiard the attainment of equilibrium conditions, a relatively thick casing shaped as an inverted U is placed over the load support arms and the balance beam. This casing is of a metal of good thernnal conductivity characteristics, such as copper or aluminum, in order that heat applied to one portion of the balance is quickly conducted to all other sensitive areas, thus effectively preventing the fornnation of air currents caused by unequal heating of the balance.

  5. Sensitive Faraday rotation measurement with auto-balanced photodetection.

    PubMed

    Chang, Chia-Yu; Wang, Likarn; Shy, Jow-Tsong; Lin, Chu-En; Chou, Chien

    2011-06-01

    A magneto-optic polarimetry based on auto-balanced photodetection is investigated. In this experiment, a commercial auto-balanced photoreceiver is adopted to measure the Faraday rotation of air. With a proper setup to utilize its noise cancellation capability, the measurement can be flexible and sensitive. The angular sensitivity is 2.99×10(-8) rad Hz(-1/2), which is about 2.7 times the shot noise limit. The measured Verdet constant of air is +1.39×10(-9) rad G(-1) cm(-1) at 634.8 nm. Significantly we applied a small AC current to induce the magnetic field, so there was no heating in the coil. In addition, a double current modulation scheme was used to demonstrate that there was no zero drift and amplifier instability in the measurement. The possibility of improvement of the angular sensitivity and the potential applications are also discussed.

  6. Effects of winter military training on energy balance, whole-body protein balance, muscle damage, soreness, and physical performance.

    PubMed

    Margolis, Lee M; Murphy, Nancy E; Martini, Svein; Spitz, Marissa G; Thrane, Ingjerd; McGraw, Susan M; Blatny, Janet-Martha; Castellani, John W; Rood, Jennifer C; Young, Andrew J; Montain, Scott J; Gundersen, Yngvar; Pasiakos, Stefan M

    2014-12-01

    Physiological consequences of winter military operations are not well described. This study examined Norwegian soldiers (n = 21 males) participating in a physically demanding winter training program to evaluate whether short-term military training alters energy and whole-body protein balance, muscle damage, soreness, and performance. Energy expenditure (D2(18)O) and intake were measured daily, and postabsorptive whole-body protein turnover ([(15)N]-glycine), muscle damage, soreness, and performance (vertical jump) were assessed at baseline, following a 4-day, military task training phase (MTT) and after a 3-day, 54-km ski march (SKI). Energy intake (kcal·day(-1)) increased (P < 0.01) from (mean ± SD (95% confidence interval)) 3098 ± 236 (2985, 3212) during MTT to 3461 ± 586 (3178, 3743) during SKI, while protein (g·kg(-1)·day(-1)) intake remained constant (MTT, 1.59 ± 0.33 (1.51, 1.66); and SKI, 1.71 ± 0.55 (1.58, 1.85)). Energy expenditure increased (P < 0.05) during SKI (6851 ± 562 (6580, 7122)) compared with MTT (5480 ± 389 (5293, 5668)) and exceeded energy intake. Protein flux, synthesis, and breakdown were all increased (P < 0.05) 24%, 18%, and 27%, respectively, during SKI compared with baseline and MTT. Whole-body protein balance was lower (P < 0.05) during SKI (-1.41 ± 1.11 (-1.98, -0.84) g·kg(-1)·10 h) than MTT and baseline. Muscle damage and soreness increased and performance decreased progressively (P < 0.05). The physiological consequences observed during short-term winter military training provide the basis for future studies to evaluate nutritional strategies that attenuate protein loss and sustain performance during severe energy deficits.

  7. Energy requirements for a swimming pool through a water-atmosphere energy balance

    SciTech Connect

    Almanza, F.; Lara, J. )

    1994-07-01

    The methodology displayed here is to calculate the energy requirements for heating a swimming pool to a desired temperature. This methodology consists of an energy balance between water-atmosphere as is used in the temperature evaluation of cooling ponds in power plants. Different mathematical expressions are given to calculate such a balance. It is necessary to know the month of the year, the ambient temperature, relative humidity, wind velocity, and solar radiation. With these parameters it is possible to know the natural temperature of the water, natural evaporation, energy needed to reach a determined swimming pool temperature and the evaporation of the heated pool.

  8. Modeling the snow surface temperature with a one-layer energy balance snowmelt model

    NASA Astrophysics Data System (ADS)

    You, J.; Tarboton, D. G.; Luce, C. H.

    2013-12-01

    ⪉bel{sec:abstract} Snow surface temperature is a key control on energy exchanges at the snow surface, particularly net longwave radiation and turbulent energy fluxes. The snow surface temperature is in turn controlled by the balance between various external fluxes and the conductive heat flux, internal to the snowpack. Because of the strong insulating properties of snow, thermal gradients in snow packs are large and nonlinear, a fact that has led many to advocate multiple layer snowmelt models over single layer models. In an effort to keep snowmelt modeling simple and parsimonious, the Utah Energy Balance (UEB) snowmelt model used only one layer but allowed the snow surface temperature to be different from the snow average temperature by using an equilibrium gradient parameterization based on the surface energy balance. Although this procedure was considered an improvement over the ordinary single layer snowmelt models, it still resulted in discrepancies between modeled and measured snowpack energy contents. In this paper we examine the parameterization of snow surface temperature in single layer snowmelt models from the perspective of heat conduction into a semi-infinite medium. We evaluate the equilibrium gradient approach, the force-restore approach, and a modified force-restore approach. In addition, we evaluate a scheme for representing the penetration of a refreezing front in cold periods following melt. We also introduce a method to adjust effective conductivity to account for the presence of ground near to a shallow snow surface. These parameterizations were tested against data from the Central Sierra Snow Laboratory, CA, Utah State University experimental farm, UT, and Subnivean snow laboratory at Niwot Ridge, CO. These tests compare modeled and measured snow surface temperature, snow energy content, snow water equivalent, and snowmelt outflow. We found that with these refinements the model is able to better represent the snowpack energy balance and

  9. Analysis of Short-Term Closure of the Surface Energy Balance in Different Seasons

    NASA Astrophysics Data System (ADS)

    Cava, D.; Contini, D.; Donateo, A.; Martano, P.

    2007-05-01

    A correct determination of the surface energy balance is an important quality test for measurements of turbulent surface fluxes. The energy balance is often not closed especially in non-homogeneous terrain or in presence of orographic obstacles. Daily energy budget is more easily balanced, because of the contribution of energy residuals of opposite sign; however short-term closure is rarely obtained. What distinguishes this study from previous ones is the effort to close short-term energy budget, and to explore the factors that mainly affect the energy imbalance during the day. To this aim we analysed data sets from southern Italy collected above a semiarid terrain during summer and fall seasons. Our analysis has shown that the global closure rate significantly improves after the correction for the error dependent on the ultrasonic anemometer angle of attack and for the error dependent on the heat storage into the soil. Furthermore a significant reduction of short-term energy residual results by taking into account the contribution to the transport by `large scale motions'. The obtained results are independent from the net incoming radiation.

  10. Energy balance regulation by endocannabinoids at central and peripheral levels.

    PubMed

    Quarta, Carmelo; Mazza, Roberta; Obici, Silvana; Pasquali, Renato; Pagotto, Uberto

    2011-09-01

    Dysregulation of the endocannabinoid system (ECS) is a universal and, perhaps, causative feature of obesity. Central nervous system (CNS) circuits that regulate food intake were initially believed to be the targets for dysregulation. However, it is increasingly evident that endocannabinoids affect food intake, energy expenditure and substrate metabolism by acting on peripheral sites. Cannabinoid type 1 receptor (CB1r) antagonists can effectively treat obesity and associated metabolic alterations but, unfortunately, cause and exacerbate mood disorders. Drugs restricted to act on peripheral CB1rs might be safer and more effective, retaining the anti-obesity effects but lacking the adverse neurodepressive reactions. This review summarizes the emerging roles of the ECS in energy balance and discusses future pharmacological approaches for developing peripherally restricted CB1r antagonists.

  11. Energy balance and photochemical processes in the inner coma

    SciTech Connect

    Huebner, W.F.; Keady, J.J.

    1982-01-01

    Energy balance and multifluid flow in the coma are described. Expansion cooling, radiative cooling, photodissociative heating, chemical heating, and relative multifluid flow are the processes determining the energy budget. In the fluid dynamics, fast atomic and molecular hydrogen are considered as separate fluids with larger collision mean free paths than the cold bulk fluid that has a larger mean molecular weight. The transition from fluid flow to free molecular flow is approximated. The model predicts hydrogen and bulk fluid flow velocities in general agreement with observations. The effects of the temperature profile and the fast hydrogen flow on the chemistry in the inner coma are investigated. Results from a model approximating conditions in Halley's comet are presented.

  12. Scalable load-balance measurement for SPMD codes

    SciTech Connect

    Gamblin, T; de Supinski, B R; Schulz, M; Fowler, R; Reed, D

    2008-08-05

    Good load balance is crucial on very large parallel systems, but the most sophisticated algorithms introduce dynamic imbalances through adaptation in domain decomposition or use of adaptive solvers. To observe and diagnose imbalance, developers need system-wide, temporally-ordered measurements from full-scale runs. This potentially requires data collection from multiple code regions on all processors over the entire execution. Doing this instrumentation naively can, in combination with the application itself, exceed available I/O bandwidth and storage capacity, and can induce severe behavioral perturbations. We present and evaluate a novel technique for scalable, low-error load balance measurement. This uses a parallel wavelet transform and other parallel encoding methods. We show that our technique collects and reconstructs system-wide measurements with low error. Compression time scales sublinearly with system size and data volume is several orders of magnitude smaller than the raw data. The overhead is low enough for online use in a production environment.

  13. The structure and energy balance of cool star atmospheres

    NASA Technical Reports Server (NTRS)

    Linsky, J. L.

    1982-01-01

    The atmospheric structure and energy balance phenomena associated with magnetic fields in the Sun are reviewed and it is shown that similar phenomena occur in cool stars. The evidence for the weakening or disappearance of transition regions and coronae is discussed together with the appearance of extended cool chromospheres with large mass loss, near V-R = 0.80 in the H-R diagram. Like the solar atmosphere, these atmospheres are not homogeneous and there is considerable evidence for plage regions with bright TR emission lines that overlie dark (presumably magnetic) star spots. The IUE observations are providing important information on the energy balance in these atmospheres that should guide theoretical calculations of the nonradiative heating rate. Recent high dispersion spectra are providing unique information concerning which components of close binary systems are the dominant contributors to the observed emission. A recent unanticipated discovery is that the transition lines are redshifted (an antiwind) in DRa (G2 Ib) and perhaps other stars. Finally, the G and K giants and supergiants are classified into three groups depending on whether their atmospheres are dominated by closed magnetic flux tubes, open field geometries, or a predominately open geometry with a few closed flux tubes embedded.

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

    PubMed

    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.

  15. Model Engine Performance Measurement From Force Balance Instrumentation

    NASA Technical Reports Server (NTRS)

    Jeracki, Robert J.

    1998-01-01

    A large scale model representative of a low-noise, high bypass ratio turbofan engine was tested for acoustics and performance in the NASA Lewis 9- by 15-Foot Low-Speed Wind Tunnel. This test was part of NASA's continuing Advanced Subsonic Technology Noise Reduction Program. The low tip speed fan, nacelle, and an un-powered core passage (with core inlet guide vanes) were simulated. The fan blades and hub are mounted on a rotating thrust and torque balance. The nacelle, bypass duct stators, and core passage are attached to a six component force balance. The two balance forces, when corrected for internal pressure tares, measure the total thrust-minus-drag of the engine simulator. Corrected for scaling and other effects, it is basically the same force that the engine supports would feel, operating at similar conditions. A control volume is shown and discussed, identifying the various force components of the engine simulator thrust and definitions of net thrust. Several wind tunnel runs with nearly the same hardware installed are compared, to identify the repeatability of the measured thrust-minus-drag. Other wind tunnel runs, with hardware changes that affected fan performance, are compared to the baseline configuration, and the thrust and torque effects are shown. Finally, a thrust comparison between the force balance and nozzle gross thrust methods is shown, and both yield very similar results.

  16. Water-Energy balance in pressure irrigation systems

    NASA Astrophysics Data System (ADS)

    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.

  17. Global Energy and Water Balances in the Latest Reanalyses

    NASA Astrophysics Data System (ADS)

    Ahn, Joong-Bae; Kang, Suchul; Park, Hye-Jin

    2016-04-01

    The recently released Japanese 55-year Reanalysis (JRA-55) data are evaluated and compared with three other global reanalyses, namely Interim version of the next European Centre for Medium-Range Weather Forecasts (ECMWF) Re-Analysis (ERRA-Interim), Modern Era Retrospective-Analysis for Research and Applications (MERRA) and Climate Forecast System Reanalysis (CFSR), in terms of global energy and water balances. All four reanalyses show an energy imbalance at TOA and surface. Especially, clouds in JRA-55 are optically weaker than those in the three other reanalyses, leading to excessive outgoing longwave radiation, which in turn causes negative net energy flux at TOA. Moreover, JRA-55 has a negative imbalance at surface and at TOA, which is attributed to systematic positive biases in latent heat flux over the ocean. As for the global water balance, all reanalyses present a similar spatial pattern of the difference between evaporation and precipitation (E-P). However, JRA-55 has a relatively strong negative (positive) E-P in the Intertropical Convergence Zone and South Pacific Convergence Zone (extratropical regions) due to overestimated precipitation (evaporation), in spite of the global net being close to zero. In time series analysis, especially in E-P, significant stepwise changes occur in MERRA, CFSR and ERA-Interim due to the changes occur in MERRA, CFRS and ERA-Interim due to the changes in the satellite observing system used in the data assimilation. Both MERRA and CFSR show a strong downward E-P shift in 1998, simultaneously with the start of the assimilation of AMSU-A sounding radiances. ERA-Interim exhibits an upward E-P shift in 1992 due to changes in observations from the SSM/I of new DMSP satellites. On the contrary, JRA-55 exhibits less trends and remains stable over time, which may be caused by newly available, homogenized observations and advances in data assimilation technique. Acknowledgements This work was funded by the Korea Meteorological

  18. Preliminary approach of the MELiSSA loop energy balance

    NASA Astrophysics Data System (ADS)

    Poulet, Lucie; Lamaze, Brigitte; Lebrun, Jean

    Long duration missions, such as the establishment of permanent bases on the lunar surface or the travel to Mars, require a huge amount of life support consumables (e.g. food, water and oxygen). Current rockets are at the moment unable to launch such a mass from Earth. Consequently Regenerative Life Support Systems are necessary to sustain long-term manned space mission to increase recycling rates and so reduce the launched mass. Thus the European and Canadian research has been concentrating on the MELiSSA (Micro-Ecological Life Support System Alternative) project over the last 20 years. MELiSSA is an Environmental Controlled Life Support System (ECLSS), i.e. a closed regenerative loop inspired of a lake ecosystem. Using light as a source of energy, MELiSSA's goal is the recovery of food, water and oxygen from CO2 and organic wastes, using microorganisms and higher plants. The architecture of a ECLSS depends widely on the mission scenario. To compare several ECLSS architectures and in order to be able to evaluate them, ESA is developing a multi criteria evaluation tool: ALISSE (Advanced LIfe Support System Evaluator). One of these criteria is the energy needed to operate the ECLSS. Unlike other criteria like the physical mass, the energy criterion has not been investigated yet and needs hence a detailed analysis. It will consequently be the focus of this study. The main objective of the work presented here is to develop a dynamic tool able to estimate the energy balance for several configurations of the MELiSSA loop. The first step consists in establishing the energy balance using concrete figures from the MELiSSA Pilot Plant (MPP). This facility located at the Universitat Autonoma de Barcelona (UAB) is aimed at the ground demonstration of the MELiSSA loop. The MELiSSA loop is structured on several subsystems; each of them is characterized by supplies, exhausts and process reactions. For the purpose of this study (i.e. a generic tool) the solver EES (Engineering

  19. Dry period plane of energy: Effects on feed intake, energy balance, milk production, and composition in transition dairy cows.

    PubMed

    Mann, S; Yepes, F A Leal; Overton, T R; Wakshlag, J J; Lock, A L; Ryan, C M; Nydam, D V

    2015-05-01

    The objective was to investigate the effect of different dry cow feeding strategies on the degree of ketonemia postpartum. Epidemiologic studies provide evidence of an association between elevated β-hydroxybutyrate (BHBA) concentrations in postpartum dairy cows and a decreased risk for reproductive success as well as increased risk for several diseases in early lactation, such as displacement of the abomasum and metritis. The plane of energy fed to cows in the prepartum period has been shown to influence ketogenesis and the degree of negative energy balance postpartum. Our hypothesis was that a high-fiber, controlled-energy diet (C) fed during the dry period would lead to a lower degree of hyperketonemia in the first weeks postpartum compared with either a high-energy diet (H), or a diet where an intermediate level of energy would only be fed in the close-up period (starting at 28d before expected parturition), following the same controlled-energy diet in the far-off period. Hyperketonemia in this study was defined as a blood BHBA concentration of ≥1.2mmol/L. Holstein cows (n=84) entering parity 2 or greater were enrolled using a randomized block design and housed in individual tiestalls. All treatment diets were fed for ad libitum intake and contained monensin. Cows received the same fresh cow ration after calving. Blood samples were obtained 3 times weekly before and after calving and analyzed for BHBA and nonesterified fatty acids (NEFA). Milk components, production, and dry matter intake were recorded and energy balance was calculated. Repeated measures ANOVA was conducted for the outcomes dry matter intake, energy balance, BHBA and NEFA concentrations, milk and energy-corrected milk yield, as well as milk composition. Predicted energy balance tended to be less negative postpartum in group C and cows in this group had fewer episodes of hyperketonemia compared with both the intermediate group and group H in the first 3 wk after calving. Postpartum BHBA and

  20. Long-term mass- and energy balance of Kongsvegen glacier, Spitzbergen

    NASA Astrophysics Data System (ADS)

    Krismer, Thomas; Obleitner, Friedrich; Kohler, Jack

    2010-05-01

    We present meteorological and glaciological data from the equilibrium line (ELA) of Kongsvegen glacier (550masl) in Svalbard, covering the period 2000 until 2008. Mean annual air temperatures for the period range from -6.9 to -10.1°C and specific net annual mass balances range from -670 to +281 mm w eq. During some years substantial superimposed ice was formed and even survived the summer. The meteorological data were homogenized and used for input and validation of mass- and energy-balance simulations. The meteorological regime at the ELA is characterized by a coreless winter and summer temperatures around 0°C. Wind conditions are largely determined by katabatic winds and topgraphically channeled upper-air winds. Net short-wave radiation is determined by cloudiness during the polar day and by the seasonal evolution of glacier surface albedo. Long-wave radiation fluxes withdraw energy throughout the year and the mean annual net radiation is almost negligible. The turbulent sensible heat fluxes constitute a comparatively strong and continuous source of energy. The latent heat flux is characterized by prevailing condensation during winter and evaporation during summer. On average, however, the turbulent fluxes provide only a small amount of heat to the glacier. Most of the energy available from the atmosphere is used for summer melt and a small amount goes into heating the near surface ice layers. Similar investigations were performed at the tongue of the glacier (170masl) for a shorter period. Here the conditions are characterized by enhanced input from the atmospheric fluxes and correspondingly increased melt rates. In addition, accumulation is usually small (>50 cm snow) and melt can also occur during winter. We then investigate whether spatially distributed mass balance can be simulated using data measured outside of the glacier. Regression models were developed to derive model input from climate data measured at a nearby research station. These models are

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

    PubMed

    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

  2. Force Measurements in Magnetic Suspension and Balance System

    NASA Technical Reports Server (NTRS)

    Kuzin, Alexander; Shapovalov, George; Prohorov, Nikolay

    1996-01-01

    The description of an infrared telemetry system for measurement of drag forces in Magnetic Suspension and Balance Systems (MSBS) is presented. This system includes a drag force sensor, electronic pack and transmitter placed in the model which is of special construction, and receiver with a microprocessor-based measuring device, placed outside of the test section. Piezosensitive resonators as sensitive elements and non-magnetic steel as the material for the force sensor are used. The main features of the proposed system for load measurements are discussed and the main characteristics are presented.

  3. Global energy and water balances in the latest reanalyses

    NASA Astrophysics Data System (ADS)

    Kang, Suchul; Ahn, Joong-Bae

    2015-11-01

    The recently released Japanese 55-year Reanalysis (JRA- 55) data are evaluated and compared with three other global reanalyses, namely Interim version of the next European Centre for Medium-Range Weather Forecasts (ECMWF) Re-Analysis (ERA-Interim), Modern Era Retrospective-Analysis for Research and Applications (MERRA) and Climate Forecast System Reanalysis (CFSR), in terms of global energy and water balances. All four reanalyses show an energy imbalance at TOA and surface. Especially, clouds in JRA-55 are optically weaker than those in the three other reanalyses, leading to excessive outgoing longwave radiation, which in turn causes negative net energy flux at TOA. Moreover, JRA-55 has a negative imbalance at surface and at TOA, which is attributed to systematic positive biases in latent heat flux over the ocean. As for the global water balance, all reanalyses present a similar spatial pattern of the difference between evaporation and precipitation (E-P). However, JRA-55 has a relatively strong negative (positive) E-P in the Intertropical Convergence Zone and South Pacific Convergence Zone (extratropical regions) due to overestimated precipitation (evaporation), in spite of the global net being close to zero. In time series analysis, especially in E-P, significant stepwise changes occur in MERRA, CFSR and ERA-Interim due to the changes in the satellite observing system used in the data assimilation. Both MERRA and CFSR show a strong downward E-P shift in 1998, simultaneously with the start of the assimilation of AMSU-A sounding radiances. ERA-Interim exhibits an upward E-P shift in 1992 due to changes in observations from the SSM/I of new DMSP satellites. On the contrary, JRA-55 exhibits less trends and remains stable over time, which may be caused by newly available, homogenized observations and advances in data assimilation technique.

  4. p75 Neurotrophin Receptor Regulates Energy Balance in Obesity.

    PubMed

    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

    2016-01-12

    Obesity and metabolic syndrome reflect the dysregulation of molecular pathways that control energy homeostasis. Here, we show that the p75 neurotrophin receptor (p75(NTR)) controls energy expenditure in obese mice on a high-fat diet (HFD). Despite no changes in food intake, p75(NTR)-null mice were protected from HFD-induced obesity and remained lean as a result of increased energy expenditure without developing insulin resistance or liver steatosis. p75(NTR) 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 p75(NTR) or transplantation of p75(NTR)-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 p75(NTR) to cAMP/PKA regulates energy balance and suggest that non-CNS neurotrophin receptor signaling could be a target for treating obesity and the metabolic syndrome.

  5. p75 neurotrophin receptor regulates energy balance in obesity

    PubMed Central

    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

  6. The global land and ocean mean energy balance

    NASA Astrophysics Data System (ADS)

    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

  7. Power Measurement Methods for Energy Efficient Applications

    PubMed Central

    Calandrini, Guilherme; Gardel, Alfredo; Bravo, Ignacio; Revenga, Pedro; Lázaro, José L.; Toledo-Moreo, F. Javier

    2013-01-01

    Energy consumption constraints on computing systems are more important than ever. Maintenance costs for high performance systems are limiting the applicability of processing devices with large dissipation power. New solutions are needed to increase both the computation capability and the power efficiency. Moreover, energy efficient applications should balance performance vs. consumption. Therefore power data of components are important. This work presents the most remarkable alternatives to measure the power consumption of different types of computing systems, describing the advantages and limitations of available power measurement systems. Finally, a methodology is proposed to select the right power consumption measurement system taking into account precision of the measure, scalability and controllability of the acquisition system. PMID:23778191

  8. Energy Balance for Random Vibrations of Piecewise-Conservative Systems

    NASA Astrophysics Data System (ADS)

    IOURTCHENKO, D. V.; DIMENTBERG, M. F.

    2001-12-01

    Vibrations of systems with instantaneous or stepwise energy losses, e.g., due to impacts with imperfect rebounds, dry friction forces(s) (in which case the losses may be treated as instantaneous ones by appropriate introduction of the response energy) and/or active feedback “bang-bang” control of the systems' response are considered. Response of such (non-linear) systems to a white-noise random excitation is considered for the case where there are no other response energy losses. Thus, a simple linear energy growth with time between “jumps” is observed. Explicit expressions for the expected response energy are derived by direct application of the stochastic differential equations calculus, which contains the expected time interval between two consecutive jumps. The latter may be predicted as a solution to the relevant first-passage problem. Perturbational analysis of the relevant PDE for this problem for a certain vibroimpact system demonstrated the possibility for using the solution to the corresponding free vibration problem as a zero order approximation. The method is applied to an s.d.o.f. system with a feedback inertia control, designed according to a certain previously introduced “generalized reversed swings law”. Extensive Monte-Carlo simulation results are presented for this system as well as for several previously analyzed ones: system with impacts; system with dry friction; system with stiffness control; pendulum with controlled length. The results are compared with those due to the asymptotic stochastic averaging approach. Both methods are shown to provide adequate accuracy far beyond the expected applicability range of the asymptotic approach (which requires both excitation intensity and losses to be small), with direct energy balance being generally superior.

  9. Mapping surface energy balance components by combining Landsat Thematic Mapper and ground-based meteorological data

    NASA Technical Reports Server (NTRS)

    Moran, M. Susan; Jackson, Ray D.; Raymond, Lee H.; Gay, Lloyd W.; Slater, Philip N.

    1989-01-01

    Surface energy balance components were evaluated by combining satellite-based spectral data with on-site measurements of solar irradiance, air temperature, wind speed, and vapor pressure. Maps of latent heat flux density and net radiant flux density were produced using Landsat TM data for three dates. The TM-based estimates differed from Bowen-ratio and aircraft-based estimates by less than 12 percent over mature fields of cotton, wheat, and alfalfa.

  10. Balanced Flow Measurement and Conditioning Technology (Balanced Orifice Plate 7,051,765 B1) for NASA Inventions and Contributions Board Invention of the Year Evaluation

    NASA Technical Reports Server (NTRS)

    Kelley, Anthony R.

    2008-01-01

    This viewgraph document reviews the Balanced Flow Measurement (BFM) and Conditioning Technology, and makes the case for this as the NASA Invention of the Year. The BFM technology makes use of a thin, multi-hole orifice plate with holes sized and placed per a unique set of equations. It produces mass flow, volumetric flow,kinelic energy,or momentum BALANCE across the face of the plate. The flow is proportional.to the square root of upstream to downstream differential pressure. Multiple holes lead to smoother pressure measurement. Measures and conditions or can limit fluid flow. This innovation has many uses in and out of NASA.

  11. An energy-balance model of glaciation cycles

    NASA Technical Reports Server (NTRS)

    Ghil, M.; Bhattacharya, K.

    1979-01-01

    A one dimensional energy balance model is presented which contains a time lagged albedo to account for the delayed dependence of continental ice sheets on temperature; it also includes a smoothing of temperature gradients in the tropics to account for the effect of the Hadley circulation on the strong flattening of meridional temperature profiles there. The model exhibits finite amplitude, sustained free oscillations; these oscillations are triggered by a change in the insulation parameter and occur in the absence of any external forcing. This model behavior strongly suggests the possibility of an almost-intransitive mechanism playing a role in glaciation cycles. This behavior also occurs on shorter time scales which might be relevant to the interannual variability of the atmosphere.

  12. An energy balance climate model with cloud feedbacks

    NASA Technical Reports Server (NTRS)

    Roads, J. O.; Vallis, G. K.

    1984-01-01

    The present two-level global climate model, which is based on the atmosphere-surface energy balance, includes physically based parameterizations for the exchange of heat and moisture across latitude belts and between the surface and the atmosphere, precipitation and cloud formation, and solar and IR radiation. The model field predictions obtained encompass surface and atmospheric temperature, precipitation, relative humidity, and cloudiness. In the model integrations presented, it is noted that cloudiness is generally constant with changing temperature at low latitudes. High altitude cloudiness increases with temperature, although the cloud feedback effect on the radiation field remains small because of compensating effects on thermal and solar radiation. The net global feedback by the cloud field is negative, but small.

  13. A stability theorem for energy-balance climate models

    NASA Technical Reports Server (NTRS)

    Cahalan, R. F.; North, G. R.

    1979-01-01

    The paper treats the stability of steady-state solutions of some simple, latitude-dependent, energy-balance climate models. For north-south symmetric solutions of models with an ice-cap-type albedo feedback, and for the sum of horizontal transport and infrared radiation given by a linear operator, it is possible to prove a 'slope stability' theorem, i.e., if the local slope of the steady-state iceline latitude versus solar constant curve is positive (negative) the steady-state solution is stable (unstable). Certain rather weak restrictions on the albedo function and on the heat transport are required for the proof, and their physical basis is discussed.

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

    PubMed

    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.

  15. Effects of continuous positive airway pressure on energy balance regulation: a systematic review

    PubMed Central

    Shechter, Ari

    2016-01-01

    Obesity is both a cause and a possible consequence of obstructive sleep apnoea (OSA), as OSA seems to affect parameters involved in energy balance regulation, including food intake, hormonal regulation of hunger/satiety, energy metabolism and physical activity. It is known that weight loss improves OSA, yet it remains unclear why continuous positive airway pressure (CPAP) often results in weight gain. The goal of this systematic review is to explore if and how CPAP affects the behaviour and/or metabolism involved in regulating energy balance. CPAP appears to correct for a hormonal profile characterised by abnormally high leptin and ghrelin levels in OSA, by reducing the circulating levels of each. This is expected to reduce excess food intake. However, reliable measures of food intake are lacking, and not yet sufficient to make conclusions. Although studies are limited and inconsistent, CPAP may alter energy metabolism, with reports of reductions in resting metabolic rate or sleeping metabolic rate. CPAP appears to not have an appreciable effect on altering physical activity levels. More work is needed to characterise how CPAP affects energy balance regulation. It is clear that promoting CPAP in conjunction with other weight loss approaches should be used to encourage optimal outcomes in OSA patients. PMID:27824596

  16. Measuring and monitoring IT using a balanced scorecard approach.

    PubMed

    Gash, Deborah J; Hatton, Todd

    2007-01-01

    Ensuring that the information technology department is aligned with the overall health system strategy and is performing at a consistently high level is a priority at Saint Luke's Health System in Kansas City, Mo. The information technology department of Saint Luke's Health System has been using the balanced scorecard approach described in this article to measure and monitor its performance for four years. This article will review the structure of the IT department's scorecard; the categories and measures used; how benchmarks are determined; how linkage to the organizational scorecard is made; how results are reported; how changes are made to the scorecard; and tips for using a scorecard in other IT departments.

  17. Surface energy balance of subarctic lowland palsa mires related to permafrost degradation

    NASA Astrophysics Data System (ADS)

    Stiegler, C.; Lindroth, A.; Johansson, M.

    2013-12-01

    During the last decades, an accelerating trend in increasing active-layer thickness and rising permafrost temperatures has been observed in the Nordic area. One region, where permafrost is particularly vulnerable to any further climate change is the Torneträsk area in northern subarctic Sweden. Within the next decades a projected ongoing climate warming and increase in snow cover will most likely lead to the disappearance of lowland permafrost in this region, affecting surface vegetation cover, greenhouse gas emissions and surface energy balance. In this study we link first results of surface energy balance measurements from lowland palsa mires in the Torneträsk region to the current state of permafrost and the degradation of peat plateaus. The study area covers several mires with similar local topographic conditions along an east-west oriented transect. Due to a strong climatic gradient, with maritime climate in the west and a more continental climate in the east, active layer thickness and permafrost temperatures generally increase from east to west while permafrost thickness decreases. In the recent years permafrost has fully disappeared at our westernmost study site while at the other investigated locations the peat plateaus show varying stages of degradation. For our measurements of energy balance components we use both a mobile energy balance tower and a stationary eddy covariance tower. Data has been collected during the growing season in 2013 by measuring all components of the surface energy budget, i.e. net radiation, turbulent fluxes of sensible and latent heat as well as ground heat fluxes. In addition, we measure active layer thickness and both soil moisture and soil temperature at various depths. First results display that the turbulent fluxes of latent heat exceed the fluxes of sensible heat at all investigated sites. The difference is more pronounced at those mires where permafrost degradation is at an advanced stage and therefore more open water

  18. Energy balance in laser ablation of metal targets

    SciTech Connect

    Sobral, H.; Villagran-Muniz, M.; Bredice, F.

    2005-10-15

    Laser-generated plasma was induced on metallic targets glued to a piezoelectric microphone and placed between the plates of a planar charged capacitor. The plasma generates a temporal redistribution of electric charge on the plates that can easily be measured by a resistor connected to the ground plate; this signal is proportional to the total number of ions removed by breakdown. Both the absorbed and scattered energies were simultaneously monitored by the photoacoustic signal and an energy meter. From these signals it was possible to determine the energy involved in each of the processes. Just above the ablation threshold most of the delivered energy is absorbed and the acoustic signal prevails compared to other contributions. Above this region, the electric signal, which is proportional to the energy involved in the ablation process, becomes dominant.

  19. Energy balance and body composition during US Army special forces training.

    PubMed

    Margolis, Lee M; Rood, Jennifer; Champagne, Catherine; Young, Andrew J; Castellani, John W

    2013-04-01

    Small Unit Tactics (SUT) is a 64-day phase of the Special Forces Qualification Course designed to simulate real-world combat operations. Assessing the metabolic and physiological responses of such intense training allows greater insights into nutritional requirements of soldiers during combat. The purpose of this study was to examine energy balance around specific training events, as well as changes in body mass and composition. Data were collected from 4 groups of soldiers (n = 36) across 10-day periods. Participants were 28 ± 5 years old, 177 ± 6 cm tall, and weighed 83 ± 7 kg. Doubly labeled water (D2(18)O) was used to assess energy expenditure. Energy intake was calculated by subtracting energy in uneaten foods from known energy in distributed foods in individually packaged combat rations or in the dining facility. Body composition was estimated from skinfold thickness measurements on days 0 and 64 of the course. Simulated urban combat elicited that largest energy deficit (11.3 ± 2.3 MJ·day(-1) (2700 ± 550 kcal·day(-1)); p < 0.05), and reduction in body mass (3.3 ± 1.9 kg; p < 0.05), during SUT, while energy balance was maintained during weapons familiarization training and platoon size raids. Over the entire course body mass decreased by 4.2 ± 3.7 kg (p < 0.01), with fat mass decreasing by 2.8 ± 2.0 kg (p < 0.01) and fat-free mass decreasing by 1.4 ± 2.8 kg (p < 0.05). The overall reduction in body mass suggests that soldiers were in a negative energy balance during SUT, with high energy deficit being observed during strenuous field training.

  20. Beam-energy dependence of charge balance functions from Au + Au collisions at energies available at the BNL Relativistic Heavy Ion Collider

    DOE PAGES

    Adamczyk, L.; Adkins, J. K.; Agakishiev, G.; ...

    2016-08-16

    Balance functions have been measured in terms of relative pseudorapidity ( Δη ) for charged particle pairs at the BNL Relativistic Heavy Ion Collider (RHIC) from Au + Au collisions atmore » $$\\sqrt{s}$$$_{NN}$$ = 7.7 GeV to 200 GeV using the STAR detector. These results are compared with balance functions measured at the CERN Large Hadron Collider from Pb + Pb collisions at $$\\sqrt{s}$$$_{NN}$$ = 2.76 TeV by the ALICE Collaboration. The width of the balance function decreases as the collisions become more central and as the beam energy is increased. In contrast, the widths of the balance functions calculated using shuffled events show little dependence on centrality or beam energy and are larger than the observed widths. Balance function widths calculated using events generated by UrQMD are wider than the measured widths in central collisions and show little centrality dependence. The measured widths of the balance functions in central collisions are consistent with the delayed hadronization of a deconfined quark gluon plasma (QGP). Finally, the narrowing of the balance function in central collisions at $$\\sqrt{s}$$$_{NN}$$ = 7.7 GeV implies that a QGP is still being created at this relatively low energy.« less

  1. Beam-energy dependence of charge balance functions from Au + Au collisions at energies available at the BNL Relativistic Heavy Ion Collider

    SciTech Connect

    Adamczyk, L.; Adkins, J. K.; Agakishiev, G.; Aggarwal, M. M.; Ahammed, Z.; Alekseev, I.; Alford, J.; Aparin, A.; Arkhipkin, D.; Aschenauer, E. C.; Averichev, G. S.; Banerjee, A.; Bellwied, R.; Bhasin, A.; Bhati, A. K.; Bhattarai, P.; Bielcik, J.; Bielcikova, J.; Bland, L. C.; Bordyuzhin, I. G.; Bouchet, J.; Brandin, A. V.; Bunzarov, I.; Burton, T. P.; Butterworth, J.; Caines, H.; Calderón de la Barca Sánchez, M.; Campbell, J. M.; Cebra, D.; Cervantes, M. C.; Chakaberia, I.; Chaloupka, P.; Chang, Z.; Chattopadhyay, S.; Chen, J. H.; Chen, H. F.; Cheng, J.; Cherney, M.; Christie, W.; Codrington, M. J. M.; Contin, G.; Crawford, H. J.; Cui, X.; Das, S.; De Silva, L. C.; Debbe, R. R.; Dedovich, T. G.; Deng, J.; Derevschikov, A. A.; Derradi de Souza, R.; di Ruzza, B.; Didenko, L.; Dilks, C.; Dong, X.; Drachenberg, J. L.; Draper, J. E.; Du, C. M.; Dunkelberger, L. E.; Dunlop, J. C.; Efimov, L. G.; Engelage, J.; Eppley, G.; Esha, R.; Evdokimov, O.; Eyser, O.; Fatemi, R.; Fazio, S.; Federic, P.; Fedorisin, J.; Feng,; Filip, P.; Fisyak, Y.; Flores, C. E.; Gagliardi, C. A.; Garand, D.; Geurts, F.; Gibson, A.; Girard, M.; Greiner, L.; Grosnick, D.; Gunarathne, D. S.; Guo, Y.; Gupta, A.; Gupta, S.; Guryn, W.; Hamad, A.; Hamed, A.; Han, L. -X.; Haque, R.; Harris, J. W.; Heppelmann, S.; Hirsch, A.; Hoffmann, G. W.; Hofman, D. J.; Horvat, S.; Huang, B.; Huang, X.; 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.; Khan, Z. H.; Kikola, D. P.; Kisel, I.; Kisiel, A.; Klein, S. R.; Koetke, D. D.; Kollegger, T.; Kosarzewski, L. K.; Kotchenda, L.; Kraishan, A. F.; 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.; Li, Z. M.; Li, X.; Li, W.; Li, Y.; Li, X.; Li, C.; Lisa, M. A.; Liu, F.; Ljubicic, T.; Llope, W. J.; Lomnitz, M.; Longacre, R. S.; Luo, X.; Ma, G. L.; Ma, R. M.; Ma, Y. G.; Magdy, N.; Mahapatra, D. P.; Majka, R.; Manion, A.; Margetis, S.; Markert, C.; Masui, H.; Matis, H. S.; McDonald, D.; Minaev, N. G.; Mioduszewski, S.; Mohanty, B.; Mondal, M. M.; Morozov, D. A.; Mustafa, M. K.; Nandi, B. K.; Nasim, Md.; Nayak, T. K.; Nigmatkulov, G.; Nogach, L. V.; Noh, S. Y.; Novak, J.; Nurushev, S. B.; Odyniec, G.; Ogawa, A.; Oh, K.; Okorokov, V.; Olvitt, D. L.; Page, B. S.; Pan, Y. X.; Pandit, Y.; Panebratsev, Y.; Pawlak, T.; Pawlik, B.; Pei, H.; Perkins, C.; Pile, P.; Planinic, M.; Pluta, J.; Poljak, N.; Poniatowska, K.; Porter, J.; Poskanzer, A. M.; Pruthi, N. K.; Przybycien, M.; Putschke, J.; Qiu, H.; Quintero, A.; Ramachandran, S.; Raniwala, R.; Raniwala, S.; Ray, R. L.; Ritter, H. G.; Roberts, J. B.; Rogachevskiy, O. V.; Romero, J. L.; Roy, A.; Ruan, L.; Rusnak, J.; Rusnakova, O.; Sahoo, N. R.; Sahu, P. K.; Sakrejda, I.; Salur, S.; Sandacz, A.; Sandweiss, J.; 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.; Simko, M.; Skoby, M. J.; Smirnov, N.; Smirnov, D.; Solanki, D.; Song, L.; Sorensen, P.; Spinka, H. M.; Srivastava, B.; Stanislaus, T. D. S.; Stock, R.; Strikhanov, M.; Stringfellow, B.; Sumbera, M.; Summa, B. J.; Sun, X. M.; Sun, Z.; Sun, Y.; Sun, X.; Surrow, B.; Svirida, D. N.; Szelezniak, M. A.; Takahashi, J.; Tang, Z.; Tang, A. H.; Tarnowsky, T.; Tawfik, A. N.; Thomas, J. H.; Timmins, A. R.; Tlusty, D.; Tokarev, M.; Trentalange, S.; Tribble, R. E.; Tribedy, P.; Tripathy, S. K.; Trzeciak, B. A.; Tsai, O. D.; Turnau, J.; Ullrich, T.; Underwood, D. G.; Upsal, I.; Van Buren, G.; van Nieuwenhuizen, G.; Vandenbroucke, M.; Varma, R.; Vasconcelos, G. M. S.; Vasiliev, A. N.; Vertesi, R.; Videbæk, F.; Viyogi, Y. P.; Vokal, S.; Voloshin, S. A.; Vossen, A.; Wang, J. S.; Wang, X. L.; Wang, Y.; Wang, H.; Wang, F.; Wang, G.; Webb, G.; Webb, J. C.; Wen, L.; Westfall, G. D.; Wieman, H.; Wissink, S. W.; Witt, R.; Wu, Y. F.; Xiao, Z.; Xie, W.; Xin, K.; Xu, N.; Xu, Z.; Xu, H.; Xu, Y.; Xu, Q. H.; Yan, W.; Yang, Y.; Yang, C.; Yang, Y.; Ye, Z.; Yepes, P.; Yi, L.; Yip, K.; Yoo, I. -K.; Yu, N.; Zbroszczyk, H.; Zha, W.; Zhang, X. P.; Zhang, Z. P.; Zhang, J. B.; Zhang, J. L.; Zhang, Y.; Zhang, S.; Zhao, F.; Zhao, J.; Zhong, C.; Zhu, Y. H.; Zhu, X.; Zoulkarneeva, Y.; Zyzak, M.

    2016-08-16

    Balance functions have been measured in terms of relative pseudorapidity ( Δη ) for charged particle pairs at the BNL Relativistic Heavy Ion Collider (RHIC) from Au + Au collisions at $\\sqrt{s}$$_{NN}$ = 7.7 GeV to 200 GeV using the STAR detector. These results are compared with balance functions measured at the CERN Large Hadron Collider from Pb + Pb collisions at $\\sqrt{s}$$_{NN}$ = 2.76 TeV by the ALICE Collaboration. The width of the balance function decreases as the collisions become more central and as the beam energy is increased. In contrast, the widths of the balance functions calculated using shuffled events show little dependence on centrality or beam energy and are larger than the observed widths. Balance function widths calculated using events generated by UrQMD are wider than the measured widths in central collisions and show little centrality dependence. The measured widths of the balance functions in central collisions are consistent with the delayed hadronization of a deconfined quark gluon plasma (QGP). Finally, the narrowing of the balance function in central collisions at $\\sqrt{s}$$_{NN}$ = 7.7 GeV implies that a QGP is still being created at this relatively low energy.

  2. Beam-energy dependence of charge balance functions from Au + Au collisions at energies available at the BNL Relativistic Heavy Ion Collider

    NASA Astrophysics Data System (ADS)

    Adamczyk, L.; Adkins, J. K.; Agakishiev, G.; Aggarwal, M. M.; Ahammed, Z.; Alekseev, I.; Alford, J.; Aparin, A.; Arkhipkin, D.; Aschenauer, E. C.; Averichev, G. S.; Banerjee, A.; Bellwied, R.; Bhasin, A.; Bhati, A. K.; Bhattarai, P.; Bielcik, J.; Bielcikova, J.; Bland, L. C.; Bordyuzhin, I. G.; Bouchet, J.; Brandin, A. V.; Bunzarov, I.; Burton, T. P.; Butterworth, J.; Caines, H.; Calderón de la Barca Sánchez, M.; Campbell, J. M.; Cebra, D.; Cervantes, M. C.; Chakaberia, I.; Chaloupka, P.; Chang, Z.; Chattopadhyay, S.; Chen, J. H.; Chen, H. F.; Cheng, J.; Cherney, M.; Christie, W.; Codrington, M. J. M.; Contin, G.; Crawford, H. J.; Cui, X.; Das, S.; De Silva, L. C.; Debbe, R. R.; Dedovich, T. G.; Deng, J.; Derevschikov, A. A.; Derradi de Souza, R.; di Ruzza, B.; Didenko, L.; Dilks, C.; Dong, X.; Drachenberg, J. L.; Draper, J. E.; Du, C. M.; Dunkelberger, L. E.; Dunlop, J. C.; Efimov, L. G.; Engelage, J.; Eppley, G.; Esha, R.; Evdokimov, O.; Eyser, O.; Fatemi, R.; Fazio, S.; Federic, P.; Fedorisin, J.; Feng, Filip, P.; Fisyak, Y.; Flores, C. E.; Gagliardi, C. A.; Garand, D.; Geurts, F.; Gibson, A.; Girard, M.; Greiner, L.; Grosnick, D.; Gunarathne, D. S.; Guo, Y.; Gupta, A.; Gupta, S.; Guryn, W.; Hamad, A.; Hamed, A.; Han, L.-X.; Haque, R.; Harris, J. W.; Heppelmann, S.; Hirsch, A.; Hoffmann, G. W.; Hofman, D. J.; Horvat, S.; Huang, B.; Huang, X.; 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.; Khan, Z. H.; Kikola, D. P.; Kisel, I.; Kisiel, A.; Klein, S. R.; Koetke, D. D.; Kollegger, T.; Kosarzewski, L. K.; Kotchenda, L.; Kraishan, A. F.; 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.; Li, Z. M.; Li, X.; Li, W.; Li, Y.; Li, X.; Li, C.; Lisa, M. A.; Liu, F.; Ljubicic, T.; Llope, W. J.; Lomnitz, M.; Longacre, R. S.; Luo, X.; Ma, G. L.; Ma, R. M.; Ma, Y. G.; Magdy, N.; Mahapatra, D. P.; Majka, R.; Manion, A.; Margetis, S.; Markert, C.; Masui, H.; Matis, H. S.; McDonald, D.; Minaev, N. G.; Mioduszewski, S.; Mohanty, B.; Mondal, M. M.; Morozov, D. A.; Mustafa, M. K.; Nandi, B. K.; Nasim, Md.; Nayak, T. K.; Nigmatkulov, G.; Nogach, L. V.; Noh, S. Y.; Novak, J.; Nurushev, S. B.; Odyniec, G.; Ogawa, A.; Oh, K.; Okorokov, V.; Olvitt, D. L.; Page, B. S.; Pan, Y. X.; Pandit, Y.; Panebratsev, Y.; Pawlak, T.; Pawlik, B.; Pei, H.; Perkins, C.; Pile, P.; Planinic, M.; Pluta, J.; Poljak, N.; Poniatowska, K.; Porter, J.; Poskanzer, A. M.; Pruthi, N. K.; Przybycien, M.; Putschke, J.; Qiu, H.; Quintero, A.; Ramachandran, S.; Raniwala, R.; Raniwala, S.; Ray, R. L.; Ritter, H. G.; Roberts, J. B.; Rogachevskiy, O. V.; Romero, J. L.; Roy, A.; Ruan, L.; Rusnak, J.; Rusnakova, O.; Sahoo, N. R.; Sahu, P. K.; Sakrejda, I.; Salur, S.; Sandacz, A.; Sandweiss, J.; 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.; Simko, M.; Skoby, M. J.; Smirnov, N.; Smirnov, D.; Solanki, D.; Song, L.; Sorensen, P.; Spinka, H. M.; Srivastava, B.; Stanislaus, T. D. S.; Stock, R.; Strikhanov, M.; Stringfellow, B.; Sumbera, M.; Summa, B. J.; Sun, X. M.; Sun, Z.; Sun, Y.; Sun, X.; Surrow, B.; Svirida, D. N.; Szelezniak, M. A.; Takahashi, J.; Tang, Z.; Tang, A. H.; Tarnowsky, T.; Tawfik, A. N.; Thomas, J. H.; Timmins, A. R.; Tlusty, D.; Tokarev, M.; Trentalange, S.; Tribble, R. E.; Tribedy, P.; Tripathy, S. K.; Trzeciak, B. A.; Tsai, O. D.; Turnau, J.; Ullrich, T.; Underwood, D. G.; Upsal, I.; Van Buren, G.; van Nieuwenhuizen, G.; Vandenbroucke, M.; Varma, R.; Vasconcelos, G. M. S.; Vasiliev, A. N.; Vertesi, R.; Videbæk, F.; Viyogi, Y. P.; Vokal, S.; Voloshin, S. A.; Vossen, A.; Wang, J. S.; Wang, X. L.; Wang, Y.; Wang, H.; Wang, F.; Wang, G.; Webb, G.; Webb, J. C.; Wen, L.; Westfall, G. D.; Wieman, H.; Wissink, S. W.; Witt, R.; Wu, Y. F.; Xiao, Z.; Xie, W.; Xin, K.; Xu, N.; Xu, Z.; Xu, H.; Xu, Y.; Xu, Q. H.; Yan, W.; Yang, Y.; Yang, C.; Yang, Y.; Ye, Z.; Yepes, P.; Yi, L.; Yip, K.; Yoo, I.-K.; Yu, N.; Zbroszczyk, H.; Zha, W.; Zhang, X. P.; Zhang, Z. P.; Zhang, J. B.; Zhang, J. L.; Zhang, Y.; Zhang, S.; Zhao, F.; Zhao, J.; Zhong, C.; Zhu, Y. H.; Zhu, X.; Zoulkarneeva, Y.; Zyzak, M.; STAR Collaboration

    2016-08-01

    Balance functions have been measured in terms of relative pseudorapidity (Δ η ) for charged particle pairs at the BNL Relativistic Heavy Ion Collider from Au + Au collisions at √{sNN}=7.7 GeV to 200 GeV using the STAR detector. These results are compared with balance functions measured at the CERN Large Hadron Collider from Pb + Pb collisions at √{sNN}=2.76 TeV by the ALICE Collaboration. The width of the balance function decreases as the collisions become more central and as the beam energy is increased. In contrast, the widths of the balance functions calculated using shuffled events show little dependence on centrality or beam energy and are larger than the observed widths. Balance function widths calculated using events generated by UrQMD are wider than the measured widths in central collisions and show little centrality dependence. The measured widths of the balance functions in central collisions are consistent with the delayed hadronization of a deconfined quark gluon plasma (QGP). The narrowing of the balance function in central collisions at √{sNN}=7.7 GeV implies that a QGP is still being created at this relatively low energy.

  3. Energy-balance and melt contributions of supraglacial lakes, Langtang Khola, Nepal

    NASA Astrophysics Data System (ADS)

    Miles, E. S.; Willis, I. C.; Pellicciotti, F.; Steiner, J. F.; Buri, P.; Arnold, N. S.

    2014-12-01

    As Himalayan debris-covered glaciers retreat and thin in response to climate warming, their long, low-gradient tongues generate substantial meltwater which often collects to form surface lakes. Supraglacial lakes on debris covered glaciers present a mechanism of atmosphere-glacier energy transfer that is poorly-studied, and only conceptually included in mass-balance studies. The ponded water can enhance energy transfer as compared to dry debris cover, while also acting as a reservoir of melt-available energy. Supraglacial lakes occur in association with debris-free ice cliffs, another poorly-constrained but critical component of glacier melt. Understanding the role of supraglacial lakes requires precise monitoring of lake volume, estimation of inlet and outlet flows, and consideration of the energy balance across three surfaces: atmosphere-lake, lake-ice, and lake-saturated debris layer. This research progresses previous modeling work on the energy and mass balance of such supraglacial lakes. Lakes were monitored during the monsoon of 2013 on Lirung Glacier in the Langtang Himal of Nepal with pressure transducers and temperature sensors, while UAV-derived DEMs were used to determine lake geometry. Lake albedo was measured to vary between 0.08 and 0.12, and a nearby on-glacier AWS was used to drive the energy balance. Results indicate that the lakes act as a significant recipient of energy, and suggest that lakes are an important part of an active supraglacial hydrologic system during the monsoon. Melt generated by the lake in contact with bare ice is calculated to be 3-5 cm/day, while energy conducted through saturated lake-bottom debris only resulted in 1-2 mm/day melt. The subaqueous melt rates are of similar magnitude to observed ice-cliff melt rates, allowing lake-cliff systems to persist. Energy leaving the lake system through englacial conduits may be the most important contribution to the glacier's mass balance, driving surface evolution to form new ice

  4. DET/MPS - The GSFC Energy Balance Programs

    NASA Technical Reports Server (NTRS)

    Jagielski, J. M.

    1994-01-01

    Direct Energy Transfer (DET) and MultiMission Spacecraft Modular Power System (MPS) computer programs perform mathematical modeling and simulation to aid in design and analysis of DET and MPS spacecraft power system performance in order to determine energy balance of subsystem. DET spacecraft power system feeds output of solar photovoltaic array and nickel cadmium batteries directly to spacecraft bus. MPS system, Standard Power Regulator Unit (SPRU) utilized to operate array at array's peak power point. DET and MPS perform minute-by-minute simulation of performance of power system. Results of simulation focus mainly on output of solar array and characteristics of batteries. Both packages limited in terms of orbital mechanics, they have sufficient capability to calculate data on eclipses and performance of arrays for circular or near-circular orbits. DET and MPS written in FORTRAN-77 with some VAX FORTRAN-type extensions. Both available in three versions: GSC-13374, for DEC VAX-series computers running VMS. GSC-13443, for UNIX-based computers. GSC-13444, for Apple Macintosh computers.

  5. Local geodetic and seismic energy balance for shallow earthquake prediction

    NASA Astrophysics Data System (ADS)

    Cannavó, Flavio; Arena, Alessandra; Monaco, Carmelo

    2015-01-01

    Earthquake analysis for prediction purposes is a delicate and still open problem largely debated among scientists. In this work, we want to show that a successful time-predictable model is possible if based on large instrumental data from dense monitoring networks. To this aim, we propose a new simple data-driven and quantitative methodology which takes into account the accumulated geodetic strain and the seismically-released strain to calculate a balance of energies. The proposed index quantifies the state of energy of the selected area and allows us to evaluate better the ingoing potential seismic risk, giving a new tool to read recurrence of small-scale and shallow earthquakes. In spite of its intrinsic simple formulation, the application of the methodology has been successfully simulated in the Eastern flank of Mt. Etna (Italy) by tuning it in the period 2007-2011 and testing it in the period 2012-2013, allowing us to predict, within days, the earthquakes with highest magnitude.

  6. Energy Balance Around Gas Injection into Oxygen Steelmaking

    NASA Astrophysics Data System (ADS)

    Sabah, Shabnam; Brooks, Geoffrey

    2016-02-01

    In the present work, a simplified approach of energy balance around gas injection into oxygen steelmaking has been carried out in a cold model. The aim is to provide an estimation of the amount of energy consumed by the different parts of the injection process such as dissipation, stirring of the bath, cavity formation, and splashing. Calculation of jet power used by different processes has been carried for various operating conditions and cavity modes ( i.e., splashing and penetrating). Calculations showed that dissipation and splashing are the dominant processes where most of the power of the jet is used, whereas cavity formation consumes the least amount. In the splashing mode, the percentage of total input power going into dissipation was about 59 to 63 pct, whereas it was found to be 2.6 to 50 pct in the penetrating mode. In splashing mode, about 30 pct power from the nozzle was used to create splash which is proved to be an efficient mode for droplet generation as less power is required to create droplets. At a certain lance height, the percentages of total input power used for splashing and dissipation were found equal. Below this lance height, all the cavities were found to be in penetrating mode. This simplified approach provides an improved understanding of the gas injection process and may be used for developing models of the injection process of steelmaking.

  7. Energy and CO2 balance of maize and grass as energy crops for anaerobic digestion.

    PubMed

    Gerin, Patrick A; Vliegen, François; Jossart, Jean-Marc

    2008-05-01

    Energy crops can be used to feed anaerobic digesters and produce renewable energy. However, sustainability of this option requires that it contributes to a net production of renewable energy and a net reduction of fossil CO2 emission. In this paper, the net balance of CO2 emission and renewable energy production is assessed for maize and grass energy crops produced in several agricultural systems relevant for Southern Belgium and surrounding areas. The calculated net energy yields are 8-25 (maize) and 7.4-15.5 (grass) MWh of renewable CH4 per MWh of fossil energy invested, depending on the agricultural option considered. After conversion to electricity, the specific CO2 emissions range from 31 to 104 kg(CO2)MWhelectricity(-1), depending on the case considered. This corresponds to a significant reduction in CO2 emissions compared to the current reference gas-steam turbine technology which produces 456 kg(CO2)MWhelectricity(-1).

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

    SciTech Connect

    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.

  9. The albedo, effective temperature, and energy balance of Neptune, as determined from Voyager data

    NASA Technical Reports Server (NTRS)

    Pearl, J. C.; Conrath, B. J.

    1991-01-01

    Data from the Voyager infrared spectrometer and radiometer (IRIS) investigation are used in determining the albedo, effective temperature, and energy balance of Neptune. From broadband radiometric observations made at phase angles of 14 deg and 134 deg, together with measurements at intermediate phase angles from the literature, an orbital mean value of 0.290 +/-0.067 is obtained for the bolometric Bond albedo. This yields an equilibrium temperature Teq = 46.6 +/-1.1 K. From thermal spectra obtained over latitudes from pole to pole an effective temperature Teff = 59.3 +/-0.8 K is derived. This represents a substantial improvement over previously determined values. The energy balance of Neptune is therefore E = 2.61 +/-0.28, which is in agreement with previous results. The reduced uncertainty in this value is due to the improved determination of the effective temperature.

  10. An Energy Balance Model to Predict Chemical Partitioning in a Photosynthetic Microbial Mat

    NASA Technical Reports Server (NTRS)

    Hoehler, Tori M.; Albert, Daniel B.; DesMarais, David J.

    2006-01-01

    Studies of biosignature formation in photosynthetic microbial mat communities offer potentially useful insights with regards to both solar and extrasolar astrobiology. Biosignature formation in such systems results from the chemical transformation of photosynthetically fixed carbon by accessory microorganisms. This fixed carbon represents a source not only of reducing power, but also energy, to these organisms, so that chemical and energy budgets should be coupled. We tested this hypothesis by applying an energy balance model to predict the fate of photosynthetic productivity under dark, anoxic conditions. Fermentation of photosynthetically fixed carbon is taken to be the only source of energy available to cyanobacteria in the absence of light and oxygen, and nitrogen fixation is the principal energy demand. The alternate fate for fixed carbon is to build cyanobacterial biomass with Redfield C:N ratio. The model predicts that, under completely nitrogen-limited conditions, growth is optimized when 78% of fixed carbon stores are directed into fermentative energy generation, with the remainder allocated to growth. These predictions were compared to measurements made on microbial mats that are known to be both nitrogen-limited and populated by actively nitrogen-fixing cyanobacteria. In these mats, under dark, anoxic conditions, 82% of fixed carbon stores were diverted into fermentation. The close agreement between these independent approaches suggests that energy balance models may provide a quantitative means of predicting chemical partitioning within such systems - an important step towards understanding how biological productivity is ultimately partitioned into biosignature compounds.

  11. Multi-scale Modeling of Energy Balance Fluxes in a Dense Tamarisk Riparian Forest

    NASA Astrophysics Data System (ADS)

    Neale, C. M.; Santos, C. A.; Watts, D.; Osterberg, J.; Hipps, L. E.; Sritharan, S. I.

    2008-12-01

    Remote sensing of energy balance fluxes has become operationally more viable over the last 10 years with the development of more robust multi-layer models and the availability of quasi-real time satellite imagery from most sensors. Riparian corridors in semi-arid and arid areas present a challenge to satellite based techniques for estimating evapotranspiration due to issues of scale and pixel resolution, especially when using the thermal infrared bands. This paper will present energy balance measurement and modeling results over a Salt Cedar (Tamarix Ramosissima) forest in the Cibola National Wildlife Refuge along the Colorado River south of Blythe, CA. The research site encompasses a 600 hectare area populated by mostly Tamarisk stands of varying density. Three Bowen ratio systems are installed on tall towers within varying densities of forest cover in the upwind footprint and growing under varying depths to the water table. An additional eddy covariance tower is installed alongside a Bowen ratio system on one of the towers. Flux data has been gathered continuously since early 2007. In the summer of 2007, a Scintec large aperture scintillometer was installed between two of the towers over 1 km apart and has been working continuously along with the flux towers. Two intensive field campaigns were organized in June 2007 and May 2008 to coincide with LANDSAT TM5, MODIS and ASTER overpasses. High resolution multispectral and thermal imagery was acquired at the same time with the USU airborne system to provide information for the up- scaling of the energy balance fluxes from tower to satellite scales. The paper will present comparisons between the different energy balance measuring techniques under the highly advective conditions of the experimental site, concentrating on the scintillometer data. Preliminary results of remotely sensed modeling of the fluxes at different scales and model complexity will also be presented.

  12. Mass and Energy Balance Modeling of Glaciers in the Upper Susitna Basin, Alaska

    NASA Astrophysics Data System (ADS)

    Hoffman, A.; Hock, R.; Aubry-Wake, C.; Bliss, A.; Gusmeroli, A.; Liljedahl, A.; Gillispie, L.; Wolken, G. J.

    2014-12-01

    The State of Alaska is reviving analyses of the Susitna River's hydroelectric potential by supporting a multitude of field and modeling studies for the proposed Susitna-Watana Hydroelectric project. Critical to any effective hydroelectric development is a firm understanding of the basin-wide controls on river runoff and how seasonal reservoir recharge may change over the course of the structure's life-span. Effectively projecting future changes in watershed-scale stream flow for the Susitna river demands understanding and quantifying glacier melt in the Alaskan range. Our research is restricted to a sub-catchment of the upper Susitna basin that feeds the Susitna River covering 2,230 km2, of which 25% is glacierized. The goals of our study are to investigate the spatial and seasonal variations of the energy balance and its components across the glaciers and to model resulting streamflow from the catchment for the summer of 2013 using two models of different complexity. We apply DEBAM, a distributive energy balance model and DETIM, an enhanced temperature-index model, both coupled to a linear-reservoir runoff model, to simulate hourly surface energy fluxes, melt rates and glacier runoff using meteorological observations from an automated weather station located in the ablation zone of the West Fork glacier. Model results are compared to measurements of streamflow and mass balance at 20 ablation stakes across the glacierized area. The largest source of energy contributing to 85% of melt is net radiation followed by the sensible and latent heat fluxes. Both models capture well the seasonal and diurnal variations in streamflow and show good agreement with the mass balance point observations. The discrepancies between modeled and measured discharge can be attributed to the high uncertainty in precipitation and initial snow cover across the unglaciated part of the basin which accounts for over 75% of the modeled area.

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

    NASA Astrophysics Data System (ADS)

    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. Modeling the water and energy balance of vegetated areas with snow accumulation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The ability to quantify soil–atmosphere water and energy exchange is important in understanding agricultural and natural ecosystems, as well as the earth’s climate. We developed a one-dimensional vertical model that calculates solar radiation, canopy energy balance, surface energy balance, snowpack ...

  15. Quality Measures for Dialysis: Time for a Balanced Scorecard

    PubMed Central

    2016-01-01

    Recent federal legislation establishes a merit-based incentive payment system for physicians, with a scorecard for each professional. The Centers for Medicare and Medicaid Services evaluate quality of care with clinical performance measures and have used these metrics for public reporting and payment to dialysis facilities. Similar metrics may be used for the future merit-based incentive payment system. In nephrology, most clinical performance measures measure processes and intermediate outcomes of care. These metrics were developed from population studies of best practice and do not identify opportunities for individualizing care on the basis of patient characteristics and individual goals of treatment. The In-Center Hemodialysis (ICH) Consumer Assessment of Healthcare Providers and Systems (CAHPS) survey examines patients' perception of care and has entered the arena to evaluate quality of care. A balanced scorecard of quality performance should include three elements: population-based best clinical practice, patient perceptions, and individually crafted patient goals of care. PMID:26316622

  16. Quality Measures for Dialysis: Time for a Balanced Scorecard.

    PubMed

    Kliger, Alan S

    2016-02-05

    Recent federal legislation establishes a merit-based incentive payment system for physicians, with a scorecard for each professional. The Centers for Medicare and Medicaid Services evaluate quality of care with clinical performance measures and have used these metrics for public reporting and payment to dialysis facilities. Similar metrics may be used for the future merit-based incentive payment system. In nephrology, most clinical performance measures measure processes and intermediate outcomes of care. These metrics were developed from population studies of best practice and do not identify opportunities for individualizing care on the basis of patient characteristics and individual goals of treatment. The In-Center Hemodialysis (ICH) Consumer Assessment of Healthcare Providers and Systems (CAHPS) survey examines patients' perception of care and has entered the arena to evaluate quality of care. A balanced scorecard of quality performance should include three elements: population-based best clinical practice, patient perceptions, and individually crafted patient goals of care.

  17. Water balance measurements and simulations of maize plants on lysimeters

    NASA Astrophysics Data System (ADS)

    Heinlein, Florian; Biernath, Christian; Klein, Christian; Thieme, Christoph; Priesack, Eckart

    2016-04-01

    In Central Europe expected major aspects of climate change are a shift of precipitation events and amounts towards winter months, and the general increase of extreme weather events like heat waves or summer droughts. This will lead to strongly changing regional water availability and will have an impact on future crop growth, water use efficiency and yields. Therefore, to estimate future crop yields by growth models accurate descriptions of transpiration as part of the water balance is important. In this study, maize was grown on weighing lysimeters (sowdate: 24 April 2013). Transpiration was determined by sap flow measurement devices (ICT International Pty Ltd, Australia) using the Heat-Ratio-Method: two temperature probes, 0.5 cm above and below a heater, detect a heat pulse and its speed which allows the calculation of sap flow. Water balance simulations were executed with different applications of the model framework Expert-N. The same pedotransfer and hydraulic functions and the same modules to simulate soil water flow, soil heat and nitrogen transport, nitrification, denitrification and mineralization were used. Differences occur in the chosen potential evapotranspiration ETpot (Penman-Monteith ASCE, Penman-Monteith FAO, Haude) and plant modules (SPASS, CERES). In all simulations ETpot is separated into a soil and a plant part using the leaf are index (LAI). In a next step, these parts are reduced by soil water availability. The sum of these parts is the actual evapotranspiration ETact which is compared to the lysimeter measurements. The results were analyzed from Mid-August to Mid-September 2013. The measured sap flow rates show clear diurnal cycles except on rainy days. The SPASS model is able to simulate these diurnal cycles, overestimates the measurements on rainy days and at the beginning of the analyzed period, and underestimates transpiration on the other days. The main reason is an overestimation of potential transpiration Tpot due to too high

  18. Water, ice, and meteorological measurements at South Cascade Glacier, Washington, 2000-01 balance years

    USGS Publications Warehouse

    Krimmel, Robert M.

    2002-01-01

    Winter snow accumulation and summer snow, firn, and ice melt were measured at South Cascade Glacier, Washington, to determine the winter and net balances for the 2000 and 2001 balance years. In 2000, the winter balance, averaged over the glacier, was 3.32 meters, and the net balance was 0.38 meters. The winter balance was the ninth highest since the record began in 1959. The net balance was greater than 33 of the 41 years since 1959. In 2001, the winter balance was 1.90 meters, and net balance was -1.57 meters. The winter balance was lower than all but 4 years since 1959, and the net balance was more negative than all but 5 other years. Runoff was measured from the glacier basin and an adjacent non-glacierized basin. Air temperature, precipitation, humidity, wind speed and solar radiation were measured nearby. Ice displacements were measured for the 1998-2001 period.

  19. Steam System Energy Conservation Measures

    SciTech Connect

    Ian Metzger, Jesse Dean

    2010-12-31

    This software requires inputs of simple system inventory information and calculates the energy and cost benefits of various retrofit opportunities. This tool includes energy conservation measures for: fixing steam leaks. This tool calculates energy savings, demand reduction, cost savings, and building life cycle costs including: simple payback, discounted payback, net-present value, and savings to investment ratio. In addition this tool also displays the environmental benefits of a project.

  20. Arid site water balance: evapotranspiration modeling and measurements

    SciTech Connect

    Gee, G.W.; Kirkham, R.R.

    1984-09-01

    In order to evaluate the magnitude of radionuclide transport at an aird site, a field and modeling study was conducted to measure and predict water movement under vegetated and bare soil conditions. Significant quantities of water were found to move below the roo of a shallow-rooted grass-covered area during wet years at the Hanford site. The unsaturated water flow model, UNSAT-1D, was resonably successful in simulating the transient behavior of the water balance at this site. The effects of layered soils on water balance were demonstrated using the model. Models used to evaluate water balance in arid regions should not rely on annual averages and assume that all precipitation is removed by evapotranspiration. The potential for drainage at arid sites exists under conditions where shallow rooted plants grow on coarse textured soils. This condition was observed at our study site at Hanford. Neutron probe data collected on a cheatgrass community at the Hanford site during a wet year indicated that over 5 cm of water drained below the 3.5-m depth. The unsaturated water flow model, UNSAT-1D, predicted water drainage of about 5 cm (single layer, 10 months) and 3.5 cm (two layers, 12 months) for the same time period. Additional field measurements of hydraulic conductivity will likely improve the drainage estimate made by UNSAT-1D. Additional information describing cheatgrass growth and water use at the grass site could improve model predictions of sink terms and subsequent calculations of water storage within the rooting zone. In arid areas where the major part of the annual precipitation occurs during months with low average potential evapotranspiration and where soils are vegetated but are coarse textured and well drained, significant drainage can occur. 31 references, 18 figures, 1 table.

  1. Energy balance and the composition of weight loss during prolonged space flight

    NASA Technical Reports Server (NTRS)

    Leonard, J. I.

    1982-01-01

    Integrated metabolic balance analysis, Skylab integrated metabolic balance analysis and computer simulation of fluid-electrolyte responses to zero-g, overall mission weight and tissue losses, energy balance, diet and exercise, continuous changes, electrolyte losses, caloric and exercise requirements, and body composition are discussed.

  2. Development of a torsion balance for adhesion measurements

    NASA Technical Reports Server (NTRS)

    Miyoshi, Kazuhisa; Maeda, Chikayoshi; Masuo, Ryuichi

    1988-01-01

    A new torsion balance for study of adhesion in ceramics is discussed. A torsion wire and a linear variable differential transformer are used to monitor load and to measure pull-off force (adhesion force). The investigation suggests that this torsion balance is valuable in studying the interfacial properties of ceramics in controlled environments such as in ultrahigh vacuum. The pull-off forces measured in dry, moist, and saturated nitrogen atmosphere demonstrate that the adhesion of silicon nitride contacts remains low at humidities below 80 percent but rises rapidly above that. The adhesion at saturation is 10 times or more greater than that below 80 percent relative humidity. The adhesion in a saturated atmosphere arises primarily from the surface tension effects of a thin film of water adsorbed on the surface. The surface tension of the water film was 58 x 10 to the minus 5 to 65 x 10 to the minus 5 power. The accepted value for water is 72.7 x 10 to the minus 5 power N/cm. Adhesion characteristics of silicon nitride in contact with metals, like the friction characteristics of silicon carbide to metal contacts, can be related to the relative chemical activity of metals in ultrahigh vacuum. The more active the metal, the higher the adhesion.

  3. Assessing circumbinary habitable zones using latitudinal energy balance modelling

    NASA Astrophysics Data System (ADS)

    Forgan, Duncan

    2014-01-01

    Previous attempts to describe circumbinary habitable zones (HZs) have been concerned with the spatial extent of the zone, calculated analytically according to the combined radiation field of both stars. By contrast to these `spatial HZs', we present a numerical analysis of the `orbital HZ', an HZ defined as a function of planet orbital elements. This orbital HZ is better equipped to handle (for example) eccentric planet orbits, and is more directly connected to the data returned by exoplanet observations. Producing an orbital HZ requires a large number of climate simulations to be run to investigate the parameter space - we achieve this using latitudinal energy balance models, which handle the insolation of the planet by both stars (including mutual eclipses), as well as the planetary atmosphere's ability to absorb, transfer and lose heat. We present orbital HZs for several known circumbinary planetary systems: Kepler-16, Kepler-34, Kepler-35, Kepler-47 and PH-1. Generally, the orbital HZs at zero eccentricity are consistent with spatial HZs derived by other authors, although we detect some signatures of variability that coincide with resonances between the binary and planet orbital periods. We confirm that Earth-like planets around Kepler-47 with Kepler-47c's orbital parameters could possess liquid water, despite current uncertainties regarding its eccentricity. Kepler-16b is found to be outside the HZ, as well as the other circumbinary planets investigated.

  4. Beyond Leptin: Emerging Candidates for the Integration of Metabolic and Reproductive Function during Negative Energy Balance.

    PubMed

    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.

  5. Beyond Leptin: Emerging Candidates for the Integration of Metabolic and Reproductive Function during Negative Energy Balance

    PubMed Central

    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. PMID:22645510

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

    NASA Astrophysics Data System (ADS)

    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

  7. Energy balance affected by electrolyte recirculation and operating modes in microbial fuel cells.

    PubMed

    Jacobson, Kyle S; Kelly, Patrick T; He, Zhen

    2015-03-01

    Energy recovery and consumption in a microbial fuel cell (MFC) can be significantly affected by the operating conditions. This study investigated the effects of electrolyte recirculation and operation mode (continuous vs sequence batch reactor) on the energy balance in a tubular MFC. It was found that decreasing the anolyte recirculation also decreased the energy recovery. Because of the open environment of the cathode electrode, the catholyte recirculation consumed 10 to 50 times more energy than the anolyte recirculation, and resulted in negative energy balances despite the reduction of the anolyte recirculation. Reducing the catholyte recirculation to 20% led to a positive energy balance of 0.0288 kWh m(-3). The MFC operated as a sequence batch reactor generated less energy and had a lower energy balance than the one with continuous operation. Those results encourage the further development of MFC technology to achieve neutral or even positive energy output.

  8. Multihadron production dynamics exploring the energy balance in hadronic and nuclear collisions

    NASA Astrophysics Data System (ADS)

    Sarkisyan, Edward K. G.; Mishra, Aditya Nath; Sahoo, Raghunath; Sakharov, Alexander S.

    2016-03-01

    The relation of multihadron production in nucleus-nucleus and (anti)proton-proton collisions is studied by exploring the collision-energy and centrality dependencies of the charged particle mean multiplicity in the measurements to date. The study is performed in the framework of the recently proposed effective-energy approach which, under the proper scaling of the collision energy, combines the constituent quark picture with Landau relativistic hydrodynamics counting for the centrality-defined effective energy of participants. Within this approach, the multiplicity energy dependence and the pseudorapidity spectra from the most central nuclear collisions are well reproduced. The study of the multiplicity centrality dependence reveals a new scaling between the measured pseudorapidity spectra and the calculations. By means of this scaling, referred to as energy-balanced limiting fragmentation scaling, one reproduces the pseudorapidity spectra for all centralities. The scaling elucidates some differences in the multiplicity and midrapidity density centrality dependence obtained at RHIC and LHC. These findings reveal an inherent similarity in the multiplicity energy dependence from the most central collisions and centrality data. Predictions are made for the mean multiplicities to be measured in proton-proton and heavy-ion collisions at the LHC.

  9. Balancing

    NASA Astrophysics Data System (ADS)

    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.

  10. Circadian dynamics in measures of cortical excitation and inhibition balance

    PubMed Central

    Chellappa, Sarah L.; Gaggioni, Giulia; Ly, Julien Q. M.; Papachilleos, Soterios; Borsu, Chloé; Brzozowski, Alexandre; Rosanova, Mario; Sarasso, Simone; Luxen, André; Middleton, Benita; Archer, Simon N.; Dijk, Derk-Jan; Massimini, Marcello; Maquet, Pierre; Phillips, Christophe; Moran, Rosalyn J.; Vandewalle, Gilles

    2016-01-01

    Several neuropsychiatric and neurological disorders have recently been characterized as dysfunctions arising from a ‘final common pathway’ of imbalanced excitation to inhibition within cortical networks. How the regulation of a cortical E/I ratio is affected by sleep and the circadian rhythm however, remains to be established. Here we addressed this issue through the analyses of TMS-evoked responses recorded over a 29 h sleep deprivation protocol conducted in young and healthy volunteers. Spectral analyses of TMS-evoked responses in frontal cortex revealed non-linear changes in gamma band evoked oscillations, compatible with an influence of circadian timing on inhibitory interneuron activity. In silico inferences of cell-to-cell excitatory and inhibitory connectivity and GABA/Glutamate receptor time constant based on neural mass modeling within the Dynamic causal modeling framework, further suggested excitation/inhibition balance was under a strong circadian influence. These results indicate that circadian changes in EEG spectral properties, in measure of excitatory/inhibitory connectivity and in GABA/glutamate receptor function could support the maintenance of cognitive performance during a normal waking day, but also during overnight wakefulness. More generally, these findings demonstrate a slow daily regulation of cortical excitation/inhibition balance, which depends on circadian-timing and prior sleep-wake history. PMID:27651114

  11. Botswana water and surface energy balance research program. Part 1: Integrated approach and field campaign results

    NASA Technical Reports Server (NTRS)

    Vandegriend, A. A.; Owe, M.; Vugts, H. F.; Ramothwa, G. K.

    1992-01-01

    The Botswana water and surface energy balance research program was developed to study and evaluate the integrated use of multispectral satellite remote sensing for monitoring the hydrological status of the Earth's surface. Results of the first part of the program (Botswana 1) which ran from 1 Jan. 1988 - 31 Dec. 1990 are summarized. Botswana 1 consisted of two major, mutually related components: a surface energy balance modeling component, built around an extensive field campaign; and a passive microwave research component which consisted of a retrospective study of large scale moisture conditions and Nimbus scanning multichannel microwave radiometer microwave signatures. The integrated approach of both components in general are described and activities performed during the surface energy modeling component including the extensive field campaign are summarized. The results of the passive microwave component are summarized. The key of the field campaign was a multilevel approach, whereby measurements by various similar sensors were made at several altitudes and resolution. Data collection was performed at two adjacent sites of contrasting surface character. The following measurements were made: micrometeorological measurements, surface temperatures, soil temperatures, soil moisture, vegetation (leaf area index and biomass), satellite data, aircraft data, atmospheric soundings, stomatal resistance, and surface emissivity.

  12. The ANIBES Study on Energy Balance in Spain: design, protocol and methodology.

    PubMed

    Ruiz, Emma; Ávila, José Manuel; Castillo, Adrián; Valero, Teresa; del Pozo, Susana; Rodriguez, Paula; Bartrina, Javier Aranceta; Gil, Ángel; González-Gross, Marcela; Ortega, Rosa M; Serra-Majem, Lluis; Varela-Moreiras, Gregorio

    2015-02-04

    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") Study was to carry out an accurate updating of food and beverage intake, dietary habits/behaviour and anthropometric data of the Spanish population (9-75 years, n=2009), as well as the energy expenditure and physical activity patterns. Anthropometry measurements (weight, height, body mass index, waist circumference, % body fat, % body water) were obtained; diet was evaluated throughout a three-day dietary record (tablet device) accompanied by a 24 h-dietary recall; physical activity was quantified by questionnaire and accelerometers were also employed. Finally, information about perception and understanding of several issues related to EB was also obtained. The ANIBES study will contribute to provide valuable useful data to inform food policy planning, food based dietary guidelines development and other health oriented actions in Spain.

  13. Environment-physiology, diet quality and energy balance: the influence of early life nutrition on future energy balance.

    PubMed

    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.

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

    NASA Astrophysics Data System (ADS)

    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

  15. When energy balance is maintained, exercise does not induce negative fat balance in lean sedentary, obese sedentary, or lean endurance-trained individuals

    PubMed Central

    Gozansky, Wendolyn S.; Barry, Daniel W.; MacLean, Paul S.; Grunwald, Gary K.; Hill, James O.

    2009-01-01

    Fat oxidation during exercise is increased by endurance training, and evidence suggests that fat oxidation during exercise is impaired in obesity. Thus the primary aim of this study was to compare the acute effects of exercise on 24-h fat oxidation and fat balance in lean sedentary [LS, n = 10, body mass index (BMI) = 22.5 ± 6.5 kg/m2], lean endurance-trained (LT, n = 10, BMI = 21.2 ± 1.2 kg/m2), and obese sedentary (OS, n = 7, BMI = 35.5 ± 4.4 kg/m2) men and women. Twenty-four-hour energy expenditure and substrate oxidation were measured under sedentary (control; CON) and exercise (EX) conditions while maintaining energy balance. During EX, subjects performed 1 h of stationary cycling at 55% of aerobic capacity. Twenty-four-hour fat oxidation did not differ on the CON or EX day in LS (43 ± 9 vs. 29 ± 7 g/day, respectively), LT (53 ± 8 vs. 42 ± 5 g/day), or OS (58 ± 7 vs. 80 ± 9 g/day). However, 24-h fat balance was significantly more positive on EX compared with CON (P < 0.01). Twenty-four-hour glucose, insulin, and free fatty acid (FFA) profiles were similar on the EX and CON days, but after consumption of the first meal, FFA concentrations remained below fasting levels for the remainder of the day. These data suggest that when exercise is performed with energy replacement (i.e., energy balance is maintained), 24-h fat oxidation does not increase and in fact, may be slightly decreased. It appears that the state of energy balance is an underappreciated factor determining the impact of exercise on fat oxidation. PMID:19833807

  16. Enhancing the calculation accuracy of performance characteristics of power-generating units by correcting general measurands based on matching energy balances

    NASA Astrophysics Data System (ADS)

    Shchinnikov, P. A.; Safronov, A. V.

    2014-12-01

    General principles of a procedure for matching energy balances of thermal power plants (TPPs), whose use enhances the accuracy of information-measuring systems (IMSs) during calculations of performance characteristics (PCs), are stated. To do this, there is the possibility for changing values of measured and calculated variables within intervals determined by measurement errors and regulations. An example of matching energy balances of the thermal power plants with a T-180 turbine is made. The proposed procedure allows one to reduce the divergence of balance equations by 3-4 times. It is shown also that the equipment operation mode affects the profit deficiency. Dependences for the divergence of energy balances on the deviation of input parameters and calculated data for the fuel economy before and after matching energy balances are represented.

  17. Towards a Sustainable Energy Balance: Progressive Efficiency and the Return of Energy Conservation

    SciTech Connect

    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.

  18. Measuring the impact of gully erosion on peatland carbon balance

    NASA Astrophysics Data System (ADS)

    Evans, Martin; James, Rothwell; John, Lindsay

    2010-05-01

    Gully erosion impacts on the carbon balance of peatlands in three ways 1) direct erosional loss of carbon, 2) Enhanced near gully decomposition due to reduced water tables, and 3) Loss of primary productivity in gullies. Representative impacts of the first two mechanisms can be derived from detailed mapping of gully extent, the third requires direct measurement of carbon sequestration. In this paper rates of sequestration at both gully edge and intact sites are compared based on multiple approaches to peat core dating (timescales of circa 30 years) , and compared with equivalent data at millennial scales estimated from published peat growth rate data. The results indicate that whilst there is a clearly demonstrable reduction in carbon sequestration due to gully erosion that at the landscape scale the direct impact of gullying through POC loss and reduced productivity is of greater importance

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

    NASA Astrophysics Data System (ADS)

    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.

  20. Drought sensitivity of Amazonian carbon balance revealed by atmospheric measurements.

    PubMed

    Gatti, L V; Gloor, M; Miller, J B; Doughty, C E; Malhi, Y; Domingues, L G; Basso, L S; Martinewski, A; Correia, C S C; Borges, V F; Freitas, S; Braz, R; Anderson, L O; Rocha, H; Grace, J; Phillips, O L; Lloyd, J

    2014-02-06

    Feedbacks between land carbon pools and climate provide one of the largest sources of uncertainty in our predictions of global climate. Estimates of the sensitivity of the terrestrial carbon budget to climate anomalies in the tropics and the identification of the mechanisms responsible for feedback effects remain uncertain. The Amazon basin stores a vast amount of carbon, and has experienced increasingly higher temperatures and more frequent floods and droughts over the past two decades. Here we report seasonal and annual carbon balances across the Amazon basin, based on carbon dioxide and carbon monoxide measurements for the anomalously dry and wet years 2010 and 2011, respectively. We find that the Amazon basin lost 0.48 ± 0.18 petagrams of carbon per year (Pg C yr(-1)) during the dry year but was carbon neutral (0.06 ± 0.1 Pg C yr(-1)) during the wet year. Taking into account carbon losses from fire by using carbon monoxide measurements, we derived the basin net biome exchange (that is, the carbon flux between the non-burned forest and the atmosphere) revealing that during the dry year, vegetation was carbon neutral. During the wet year, vegetation was a net carbon sink of 0.25 ± 0.14 Pg C yr(-1), which is roughly consistent with the mean long-term intact-forest biomass sink of 0.39 ± 0.10 Pg C yr(-1) previously estimated from forest censuses. Observations from Amazonian forest plots suggest the suppression of photosynthesis during drought as the primary cause for the 2010 sink neutralization. Overall, our results suggest that moisture has an important role in determining the Amazonian carbon balance. If the recent trend of increasing precipitation extremes persists, the Amazon may become an increasing carbon source as a result of both emissions from fires and the suppression of net biome exchange by drought.

  1. Energy and water balance response of a vegetated wetland to herbicide treatment of invasive Phragmites australis

    NASA Astrophysics Data System (ADS)

    Mykleby, Phillip M.; Lenters, John D.; Cutrell, Gregory J.; Herrman, Kyle S.; Istanbulluoglu, Erkan; Scott, Durelle T.; Twine, Tracy E.; Kucharik, Christopher J.; Awada, Tala; Soylu, Mehmet E.; Dong, Bo

    2016-08-01

    The energy and water balance of a Phragmites australis dominated wetland in south central Nebraska was analyzed to assess consumptive water use and the potential for "water savings" as a result of vegetation eradication via herbicide treatment. Energy balance measurements were made at the field site for two growing seasons (treated and untreated), including observations of net radiation, heat storage, and sensible heat flux, which was measured using a large-aperture scintillometer. Latent heat flux was calculated as a residual of the energy balance, and comparisons were made between the two growing seasons and with model simulations to examine the relative impacts of vegetation removal and climate variability. Observed ET rates dropped by roughly 32% between the two growing seasons, from a mean of 4.4 ± 0.7 mm day-1 in 2009 (with live vegetation) to 3.0 ± 0.8 mm day-1 in 2010 (with dead P. australis). These results are corroborated by the Agro-IBIS model simulations, and the reduction in ET implies a total "water savings" of 245 mm over the course of the growing season. The significant decreases in ET were accompanied by a more-than-doubling of sensible heat flux, as well as a ∼60% increase in heat storage due to decreased LAI. Removal of P. australis was also found to cause measurable changes in the local micrometeorology at the wetland. Consistent with the observed increase in sensible heat flux during 2010, warmer, drier, windier conditions were observed in the dead, P. australis section of the wetland, compared to an undisturbed section of live, native vegetation. Modeling results suggest that the elimination of transpiration in 2010 was partially offset by an increase in surface evaporation, thereby reducing the subsequent water savings by roughly 60%. Thus, the impact of vegetation removal depends on the local climate, depth to groundwater, and management decisions related to regrowth of vegetation.

  2. Calcium, dairy products, and energy balance in overweight adolescents: a controlled trial1234

    PubMed Central

    Campbell, Wayne W; Teegarden, Dorothy; Craig, Bruce A; Martin, Berdine R; Singh, Rajni; Braun, Michelle M; Apolzan, John W; Hannon, Tamara S; Schoeller, Dale A; DiMeglio, Linda A; Hickey, Yvonne; Peacock, Munro

    2011-01-01

    Background: Dairy product and calcium consumption have been associated with modifying body fat and body weight in children and adults. Objective: In overweight adolescent boys and girls, we aimed to determine the effect of the doubling of habitual calcium intake to the recommended intake from dairy or calcium carbonate on energy balance and purported mechanisms including fecal fat excretion, macronutrient use, and parathyroid hormone suppression. Design: Twenty-five girls with a mean (±SD) BMI (in kg/m2) of 33 ± 5 and 17 boys with a BMI of 28 ± 5, aged 12–15 y, participated in two 3-wk controlled feeding sessions that used a crossover design in random order as a summer research camp. In one session, 756 mg Ca/d was consumed; in the other session, an additional 650 mg Ca/d was provided as dairy or calcium carbonate supplements that were matched to the control in macronutrient content. Total energy and macronutrient intakes were controlled and were the same for the 2 sessions for each subject. Primary outcome measures were energy balance, fecal fat excretion, lipid oxidation, and postprandial energy expenditure. Results: There were no effects of quantity or source of calcium on energy or fat balance, despite calcium-induced increases (P <0.01) in postprandial serum parathyroid hormone suppression. Conclusion: These data lend little evidence to support the proposed mechanisms for the relation between an increase in calcium intake from calcium carbonate or dairy and weight loss or weight maintenance in children. This trial was registered at clinicaltrials.gov as NCT00592137. PMID:21918216

  3. Estimating the actual ET from a pecan farm using the OPEC energy-balance and Penman- Monteith methods

    NASA Astrophysics Data System (ADS)

    Debele, B.; Bawazir, S. A.

    2006-12-01

    Accurate estimation of ET from field crops/orchards is the basis for better irrigation water management. In areas like Mesilla Valley, NM, where water is scarce, it is even more important to precisely determine the crop ET. An OPEC energy balance system was run for 117 days (June 22 October 14, 2001) in a matured pecan farm at Mesilla Valley, NM. The actual evapotranspiration (ET) from pecan orchards was determined from the surface energy balance as a residual, having measured the net radiation, soil heat flux, and sensible heat components using the OPEC method. Since pecans are large trees, we have also examined the effect of including thermal energies stored in the air (Ga) and plant canopy (Gc), on top of the commonly used thermal energy stored in the soil (Gs), on surface energy balance, and hence ET. The results indicate that incorporating thermal energies stored in the air and canopy has a significant effect on total energy storage for shorter temporal resolutions, such as 30-minutes and an hour. Conversely, for longer temporal resolutions (e.g., diurnal and monthly averages), the effect of including thermal energies stored in the air and vegetation on total thermal energy storage is negligible. Our results also showed that the bulk of the total thermal energy storage (G = Gs + Ga + Gc) in the surface energy balance was stored in the soil (Gs). In addition, we have also determined the crop coefficient (Kc) of pecan by combining the actual ET obtained from the OPEC method and potential ET (ET0) calculated using weather data in the surrounding area. Our average pecan Kc values were comparable with the ones reported by other researchers using different methods. We conclude that the OPEC energy balance method can be used to calculate Kc values for pecan whereby farmers and extension agents use the calculated Kc values in combination with ET0 to determine the consumptive use of pecan trees.

  4. Energy balance in nanosecond pulse discharges in nitrogen and air

    NASA Astrophysics Data System (ADS)

    Shkurenkov, Ivan; Adamovich, Igor V.

    2016-02-01

    Kinetic modeling is used to analyze energy partition and energy transfer in nanosecond pulse discharges sustained between two spherical electrodes in nitrogen and air. The modeling predictions are compared with previous time-resolved temperature and {{\\text{N}}2}≤ft(X {}1Σ\\text{g}+,v=0-9\\right) vibrational population measurements by picosecond broadband coherent anti-Stokes Raman spectroscopy (CARS) and phase-locked Schlieren imaging. The model shows good agreement with experimental data, reproducing experimental discharge current pulse waveforms, as well as dominant processes of energy transfer in the discharge and the afterglow. Specifically, the results demonstrate that the temperature rise in the plasma occurs in two stages, (i) ‘rapid’ heating on sub-acoustic time scale, dominated by {{\\text{N}}2}≤ft(A {}3Σ\\text{u}+\\right) energy pooling processes, N2(B 3Πg) and N(2P,2D) quenching (in nitrogen), and by quenching of excited electronic states of N2 molecules by O2 (in air), and (ii) ‘slow’ heating due to N2 vibrational relaxation by O atoms (in air), nearly completely missing in nitrogen. Comparison of the model predictions with N2 vibrational level populations confirms that the N2 vibrational temperature rises after the discharge pulse is caused by the ‘downward’ vibrational-vibrational exchange depopulating higher vibrational levels and populating vibrational level v  =  1. The model reproduces temporal dynamics of vibrational level populations and temperature in the discharge and the afterglow, indicating that energy partition among different modes (vibrational, electronic, dissociation, and ionization) is predicted accurately. At the present conditions, energy fraction coupled to the positive column of the discharge filament in air is approximately 50%, with the rest coupled to the cathode layer. Nearly 10% of the total pulse energy is spent on O atom generation, and about 10% is thermalized on a sub-acoustic time scale

  5. Energy Balance, Evapo-transpiration and Dew deposition in the Dead Sea Valley

    NASA Astrophysics Data System (ADS)

    Metzger, Jutta; Corsmeier, Ulrich

    2016-04-01

    The Dead Sea is a unique place on earth. It is a terminal hypersaline lake, located at the lowest point on earth with a lake level of currently -429 m above mean sea level (amsl). It is located in a transition zone of semiarid to arid climate conditions, which makes it highly sensible to climate change (Alpert1997, Smiatek2011). The Virtual Institute DEad SEa Research Venue (DESERVE) is an international project funded by the German Helmholtz Association and was established to study coupled atmospheric hydrological, and lithospheric processes in the changing environment of the Dead Sea. At the moment the most prominent environmental change is the lake level decline of approximately 1 m / year due to anthropogenic interferences (Gertman, 2002). This leads to noticeable changes in the fractions of the existing terrestrial surfaces - water, bare soil and vegetated areas - in the valley. Thus, the partitioning of the net radiation in the valley changes as well. To thoroughly study the atmospheric and hydrological processes in the Dead Sea valley, which are driven by the energy balance components, sound data of the energy fluxes of the different surfaces are necessary. Before DESERVE no long-term monitoring network simultaneously measuring the energy balance components of the different surfaces in the Dead Sea valley was available. Therefore, three energy balance stations were installed at three characteristic sites at the coast-line, over bare soil, and within vegetation, measuring all energy balance components by using the eddy covariance method. The results show, that the partitioning of the energy into sensible and latent heat flux on a diurnal scale is totally different at the three sites. This results in gradients between the sites, which are e.g. responsible for the typical diurnal wind systems at the Dead Sea. Furthermore, driving forces of evapo-transpiration at the sites were identified and a detailed analysis of the daily evaporation and dew deposition rates

  6. The energy balance of wind waves and the remote sensing problem

    NASA Technical Reports Server (NTRS)

    Hasselmann, K.

    1972-01-01

    Measurements of wave growth indicate an energy balance of the wave spectrum governed primarily by input from the atmosphere, nonlinear transfer to shorter and longer waves, and advection. The pronounced spectral peak and sharp low frequency cut-off characteristic of fetch-limited spectra are explained as a self-stabilizing feature of the nonlinear wave-wave interactions. The momentum transferred from the atmosphere to the wind waves accounts for a large part of the wind drag. These findings are relevant for remote microwave sensing of the sea surface by backscatter and passive radiometry methods.

  7. The seasonal CO2 cycle on Mars - An application of an energy balance climate model

    NASA Technical Reports Server (NTRS)

    James, P. B.; North, G. R.

    1982-01-01

    Energy balance climate models of the Budyko-Sellers variety are applied to the carbon-dioxide cycle on Mars. Recent data available from the Viking mission, in particular the seasonal pressure variations measured by Viking landers, are used to constrain the models. No set of parameters was found for which a one-dimensional model parameterized in terms of ground temperature gave an adequate fit to the observed pressure variations. A modified, two-dimensional model including the effects of dust storms and the polar hood reasonably reproduces the pressure curve, however. The implications of these results for Martian climate changes are discussed.

  8. The National Energy Strategy: A balanced program?. Proceedings of the nineteenth annual Illinois energy conference

    SciTech Connect

    Not Available

    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.

  9. A decade of changing surface energy balance components over a large water region

    NASA Astrophysics Data System (ADS)

    Petchprayoon, Pakorn; Blanken, Peter D.; Hussein, Khalid; Abdalati, Waleed; Lawavirotwong, Siam

    2016-10-01

    This study has investigated the physical processes of energy exchange between the water surface and atmosphere over Lake Huron. The four components of surface energy balance, including net radiation, latent heat, sensible heat, and heat storage, were estimated using the eleven years (2002-2012) daily MODIS data together with in-situ measurements. Good agreement was found between the seasonal turbulent heat fluxes calculated from satellite data and those from the direct measurements (eddy covariance method) with correlation coefficients of 0.94 and 0.95 for sensible heat and latent heat, respectively. There were temporal, spatial heterogeneities, and strong seasonal pattern for all of the four components, which were very high in summer and low in winter for net radiation and heat storage. In contrast, latent heat and sensible heat were very high in the winter and very low in the summer. Trend analysis revealed long term changes for each of the energy balance components, particularly the increase in latent heat which was equivalent to evaporation rate of 0.017 mm m-2 per year, indicating that lake evaporation increased by 0.19 mm m-2 over the eleven years observation period. This was possibly a result of a smaller amount of over lake ice cover and an increase in surface water temperature of Lake Huron.

  10. Sex-related differences in energy balance in response to caloric restriction.

    PubMed

    Valle, A; Català-Niell, A; Colom, B; García-Palmer, F J; Oliver, J; Roca, P

    2005-07-01

    Sex-related differences in energy balance were studied in young Wistar rats fed standard chow pellets either ad libitum or in restricted amounts (60% of ad libitum intake) for 100 days. Caloric intake, indirect calorimetry, organ and adipose tissue weights, energy efficiency, liver mitochondrial respiration rate, and brown adipose tissue (BAT) uncoupling protein-1 (UCP1) content were measured. Ad libitum-fed females showed greater oxygen consumption (Vo(2)) and carbon dioxide production (Vco(2)) and lower energy efficiency than males. Caloric restriction induced a chronic drop of Vo(2) and Vco(2) in females but not in males over the period studied. Restricted females showed a better conservation of metabolic active organ mass and a greater decrease in adipose depots than restricted males. Moreover, changes of BAT size and UCP1 content suggest that BAT may be the main cause responsible for sex differences in the response of energy balance to caloric restriction. In conclusion, our results indicate that females under caloric restriction conditions deactivate facultative thermogenesis to a greater degree than males. This ability may have obvious advantages for female survival and therefore the survival of the species when food is limiting.

  11. Progress and challenges in the estimation of the global energy balance

    NASA Astrophysics Data System (ADS)

    Wild, Martin

    2017-02-01

    While enormous progress in the determination of the global energy fluxes in and out of the climate system was made in the past decades due to the installation of sophisticated space-born observation systems, substantial discrepancies remained in the estimated and simulated surface energy budgets, as they cannot be directly measured from space. The increasing availability of accurate surface observations, improvements in the satellite retrievals of surface fluxes and model advancement, however, lead to a recent convergence of independent estimates on some of the global mean surface energy balance components to within a few Wm-2. This suggests that we are approaching a stage where we are not only confident in the magnitudes of the global annual mean energy balance components at the TOA, but increasingly also at the surface. Consensus emerges on a global mean surface downward shortwave flux near 185 Wm-2, as well as global mean surface downward and upward longwave fluxes slightly above 340 Wm-2 and below 400 Wm-2, respectively. Taking into account remaining uncertainties in the surface albedo, this implies a surface absorbed shortwave radiation near or somewhat above 160 Wm-2, which leaves an atmospheric shortwave absorption of nearly 80 Wm-2, considering a total shortwave absorption of 240 Wm-2 in the global climate system. Thus, 2/3 of the absorption of shortwave radiation in the climate system takes place at the surface, 1/3 in the atmosphere. Given the above estimates, the global mean surface net radiation (surface radiation balance) appears to be around 105 Wm-2. The partitioning of this radiative energy at the Earth's surface into sensible and latent heat is only weekly constrained by direct observations and is still afflicted with considerable uncertainties. The best estimate of global mean surface net radiation near 105 Wm-2 promoted here should, however, enable a consistent representation of the magnitudes of the global energy and water cycles within their

  12. Water, ice, meteorological, and speed measurements at South Cascade Glacier, Washington, 1999 balance year

    USGS Publications Warehouse

    Krimmel, Robert M.

    2001-01-01

    Winter snow accumulation and summer snow, firn, and ice melt were measured at South Cascade Glacier, Washington, to determine the winter and net balances for the 1999 balance year. The 1999 winter snow balance, averaged over the glacier, was 3.59 meters, and the net balance was 1.02 meters. Since the winter balance record began in 1959, only three winters have had a higher winter balance. Since the net balance record began in 1953, only 2 years have had a greater positive net balance than 1999. Runoff was measured from the glacier and an adjacent non-glacierized basin. Air temperature, precipitation, and humidity were measured nearby, and ice speed was measured. This report makes these data available to the glaciological and climatological community.

  13. Use of ground-based remotely sensed data for surface energy balance calculations during Monsoon '90

    NASA Technical Reports Server (NTRS)

    Moran, M. S.; Kustas, William P.; Vidal, Alain; Stannard, David I.; Blanford, James

    1991-01-01

    Surface energy balance was evaluated at a semiarid watershed using direct and indirect measurements of the turbulent fluxes, a remote technique based on measurements of surface reflectance and temperature, and conventional meteorological information. Comparison of remote estimates of net radiant flux and soil heat flux densities with measured values showed errors on the order of +/-40 W/sq m. To account for the effects of sparse vegetation, semi-empirical adjustments to aerodynamic resistance were required for evaluation of sensible heat flux density (H). However, a significant scatter in estimated versus measured latent heat flux density (LE) was still observed, +/-75 W/sq m over a range from 100-400 W/sq m. The errors of H and LE estimates were reduced to +/-50 W/sq m when observations were restricted to clear sky conditions.

  14. Walk-based measure of balance in signed networks: Detecting lack of balance in social networks

    NASA Astrophysics Data System (ADS)

    Estrada, Ernesto; Benzi, Michele

    2014-10-01

    There is a longstanding belief that in social networks with simultaneous friendly and hostile interactions (signed networks) there is a general tendency to a global balance. Balance represents a state of the network with a lack of contentious situations. Here we introduce a method to quantify the degree of balance of any signed (social) network. It accounts for the contribution of all signed cycles in the network and gives, in agreement with empirical evidence, more weight to the shorter cycles than to the longer ones. We found that, contrary to what is generally believed, many signed social networks, in particular very large directed online social networks, are in general very poorly balanced. We also show that unbalanced states can be changed by tuning the weights of the social interactions among the agents in the network.

  15. Lysimetric evaluation of simplified surface energy balance approach in the Texas high plains

    USGS Publications Warehouse

    Gowda, P.H.; Senay, G.B.; Howell, T.A.; Marek, T.H.

    2009-01-01

    Numerous energy balance (EB) algorithms have been developed to make use of remote sensing data to estimate evapotranspiration (ET) regionally. However, most EB models are complex to use and efforts are being made to simplify procedures mainly through the scaling of reference ET. The Simplified Surface Energy Balance (SSEB) is one such method. This approach has never been evaluated using measured ET data. In this study, the SSEB approach was applied to 14 Landsat TM images covering a major portion of the Southern High Plains that were acquired during 2006 and 2007 cropping seasons. Performance of the SSEB was evaluated by comparing estimated ET with measured daily ET from four large monolithic lysimeters at the USDA-ARS Conservation and Production Research Laboratory, Bushland, Texas. Statistical evaluation of results indicated that the SSEB accounted for 84% of the variability in the measured ET values with a slope and intercept of 0.75 and 1.1 mm d-1, respectively. Considering the minimal amount of ancillary data required and excellent performance in predicting daily ET, the SSEB approach is a promising tool for mapping ET in the semiarid Texas High Plains and in other parts of the world with similar hydro-climatic conditions.

  16. Lysimetric Evaluation of Simplified Surface Energy Balance Approach in the Texas High Plains

    USGS Publications Warehouse

    Senay, Gabriel B.; Gowda, P.H.; Howell, T.A.; Marek, T.H.

    2009-01-01

    Numerous energy balance (EB) algorithms have been developed to make use of remote sensing data to estimate evapotranspiration (ET) regionally. However, most EB models are complex to use and efforts are being made to simplify procedures mainly through the scaling of reference ET. The Simplified Surface Energy Balance (SSEB) is one such method. This approach has never been evaluated using measured ET data. In this study, the SSEB approach was applied to fourteen Landsat TM images covering a major portion of the Southern High Plains that were acquired during 2006 and 2007 cropping seasons. Performance of the SSEB was evaluated by comparing estimated ET with measured daily ET from four large monolithic lysimeters at the USDA-ARS Conservation and Production Research Laboratory, Bushland, Texas. Statistical evaluation of results indicated that the SSEB accounted for 84% of the variability in the measured ET values with a slope and intercept of 0.75 and 1.1 mm d-1, respectively. Considering the minimal amount of ancillary data required and excellent performance in predicting daily ET, the SSEB approach is a promising tool for mapping ET in the semiarid Texas High Plains and in other parts of the world with similar hydro-climatic conditions.

  17. The radiation balance of the earth-atmosphere system from Nimbus 3 radiation measurements

    NASA Technical Reports Server (NTRS)

    Raschke, E.; Vonderhaar, T. H.; Pasternak, M.; Bandeen, W. R.

    1973-01-01

    The radiation balance of the earth-atmosphere system and its components was computed from global measurements of radiation reflected and emitted from the earth to space. These measurements were made from the meteorological satellite Nimbus 3 during the periods from April 16 to August 15, 1969; October 3 to 17, 1969; and January 21 to February 3, 1970. Primarily the method of evaluation, its inherent assumptions, and possible error sources were discussed. Results are presented by various methods: (1) global, hemispherical, and zonal averages obtained from measurements in all semimonthly periods and (2) global maps of the absorbed solar radiation, the albedo, the outgoing longwave radiation, and the radiation balance obtained from measurements during semimonthly periods in each season (May 1 to 15, July 16 to 31, and October 3 to 17, 1969, and January 21 to February 3, 1970). Annual global averages of the albedo and of the outgoing longwave radiation were determined. These values balance to within 1 percent the annual global energy input by solar radiation that was computed for a solar constant.

  18. Measuring and Modelling the Carbon Balance of Pinus palustris Savannas

    NASA Astrophysics Data System (ADS)

    Wright, J. K.; Williams, M. D.; Mitchell, R. J.; Starr, G.; McGee, J.; Whelan, A.

    2011-12-01

    Longleaf pine savannas currently occupy 1.4 million hectares in the South Eastern USA - only 2.6% of their original range. These fire-dependent ecosystems are highly biodiverse and of economic and ecological importance to the region. This region of the United States, however, is increasingly prone to severe drought, including a classified "exceptional" drought in 2011. Drought occurrence and severity are likely to increase in future climate scenarios. Moreover, increasing drought and accompanying wildfire will influence the carbon balance of the South East, a region identified as having the highest carbon sequestration potential in the USA. Thus, understanding the effects of drought on the native longleaf pine savanna land cover, therefore, is of both scientific and economic interest. Longleaf pine exists over a wide soil moisture gradient, driven by the texture and drainage capacity of the soils. These ecosystems therefore provide a natural laboratory for exploring the interaction between productivity, fire and water use. Here we present results of a 3 year study comparing the ecophysiology and carbon balance of two adjacent (5 mile separation) longleaf pine savanna flux sites, one xeric, one mesic. A process-based model (Soil-Plant-Atmosphere - SPA) and leaf-level measurements of photosynthesis and water use in drought and non-drought periods have enabled the authors to partition the carbon fluxes observed at each site into three functional groups (C4 understorey, C3 canopy and mid-storey). Results of this study show that the comparative overall productivity of wet and dry longleaf pine savannas varies through the year, with both wet and dry sites achieving similar productivity in the summer months but with the wet site exceeding the dry site during winter. We hypothesise that this difference is due to the activity of the seasonal C4 understorey. Results from SPA, flux data and field measurements suggest the understorey, dominated by the C4 grass Aristida stricta

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

    NASA Astrophysics Data System (ADS)

    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.

  20. Alternative strategies for energy recovery from municipal solid waste Part A: Mass and energy balances.

    PubMed

    Consonni, S; Giugliano, M; Grosso, M

    2005-01-01

    This two-part paper assesses four strategies for energy recovery from municipal solid waste (MSW) by dedicated waste-to-energy (WTE) plants generating electricity through a steam cycle. The feedstock is the residue after materials recovery (MR), assumed to be 35% by weight of the collected MSW. In strategy 1, the MR residue is fed directly to a grate combustor. In strategy 2, the MR residue is first subjected to light mechanical treatment. In strategies 3 and 4, the MR residue is converted into RDF, which is combusted in a fluidized bed combustor. To examine the relevance of scale, we considered a small waste management system (WMS) serving 200,000 people and a large WMS serving 1,200,000 people. A variation of strategy 1 shows the potential of cogeneration with district heating. The assessment is carried out by a Life Cycle Analysis where the electricity generated by the WTE plant displaces electricity generated by fossil fuel-fired steam plants. Part A focuses on mass and energy balances, while Part B focuses on emissions and costs. Results show that treating the MR residue ahead of the WTE plant reduces energy recovery. The largest energy savings are achieved by combusting the MR residue "as is" in large scale plants; with cogeneration, primary energy savings can reach 2.5% of total societal energy use.

  1. Universality of particle production and energy balance in hadronic and nuclear collisions

    NASA Astrophysics Data System (ADS)

    Nath Mishra, Aditya; Sarkisyan, Edward K. G.; Sahoo, Raghunath; Sakharov, Alexander S.

    2016-07-01

    The multihadron production in nucleus-nucleus and (anti)proton-proton collisions is studied by exploring the collision-energy and centrality dependencies of the mean multiplicity in the existing data. The study is performed in the framework of the recently proposed effective-energy approach which combines the constituent quark picture and Landau hydrodynamics counting for the centrality-defined effective energy of participants. Within this approach, the multiplicity energy dependence and the pseudorapidity spectra from the most central nuclear collisions are well reproduced. The study of the multiplicity centrality dependence reveals a new scaling between the measured pseudorapidity spectra and the calculations. Using this scaling, called the energy balanced limiting fragmentation scaling, the pseudorapidity spectra are well reproduced for all centralities. The scaling clarifies some differences in the multiplicity and midrapidity density centrality dependence from RHIC and LHC. A similarity in the multiplicity energy dependence in the most central collisions and centrality data is shown. Predictions are drawn for the mean multiplicities to be measured in hadronic and heavy-ion collisions at the LHC.

  2. Water, ice, and meteorological measurements at South Cascade Glacier, Washington, 1994 balance year

    USGS Publications Warehouse

    Krimmel, R.M.

    1995-01-01

    Winter snow accumulation and summer snow, firn, and ice melt were measured at South Cascade Glacier, Washington to determine the winter and net balances for the 1994 balance year. The 1994 winter balance, averaged over the glacier, was 2.39 meters, and the net balance was -1.60 meters. The winter balance was approximately that of the 1977-94 average winter balance. The net balance was more negative than the 1977-94 average net balance of -1.02 meters. Runoff was measured from the glacier and an adjacent non- glacierized basin. Air temperature, precipitation, barometric pressure, solar radiation, and wind speed were measured nearby. This report makes these data available to the glaciological and climatological community.

  3. Water, ice, and meteorological measurements at South Cascade Glacier, Washington, 1995 balance year

    USGS Publications Warehouse

    Krimmel, R.M.

    1996-01-01

    Winter snow accumulation and summer snow, firn, and ice melt were measured at South Cascade Glacier, Washington to determine the winter and net balances for the 1995 balance year. The 1995 winter balance, averaged over the glacier, was 2.86 meters, and the net balance was -0.69 meter. The winter balance was approximately 0.5 meter greater than the 1977-94 average winter balance. The net balance was approximately 0.3 meter less negative than the 1977-94 average net balance. Runoff was measured from the glacier and an adjacent non-glacierized basin. Air temperature, precipitation, barometric pressure, solar radiation, and wind speed were measured adjacent to the glacier. This report makes these data available to the glaciological and climatological community.

  4. Water, ice, and meteorological measurements at South Cascade Glacier, Washington, 1996 balance year

    USGS Publications Warehouse

    Krimmel, Robert M.

    1997-01-01

    Winter snow accumulation and summer snow, firn, and ice melt were measured at South Cascade Glacier, Washington to determine the winter and net balances for the 1996 balance year. The 1996 winter balance, averaged over the glacier, was 2.94 meters, and the net balance was 0.10meter. The winter balance was approximately 0.6 meter greater than the 1977-95 average winter balance (2.30 meters). The net balance, which was positive for the first time since 1984, was more than a meter greater than the 1977-95 average net balance (-0.96 meter). The glacier retreated about 15 meters from its 1995 position. Runoff was measured from the glacier and an adjacent non-glacierized basin. Air temperature, precipitation, and barometric pressure were measured nearby. This report makes these data available to the glaciological and climatological community

  5. Energy and water balance studies of a snow cover during snowmelt period at a high arctic site

    NASA Astrophysics Data System (ADS)

    Bruland, O.; Maréchal, D.; Sand, K.; Killingtveit, Å.

    The predicted global warming is supposed to have an enhanced effect on the arctic regions. How this will influence the water, carbon dioxide and methane balances in the European arctic tundra is the objective of the EU-funded project ``Understanding Land Surface Physical Processes in the Arctic'' (LAPP), to which where SINTEF is one of several contributors. The snow cover is one of the limiting factors for these exchange processes and knowledge of how it behaves and will behave under a different climate is important. Data collected for water and energy balance studies in an area close to Ny-Ålesund at 79°N at Svalbard are the basis of this study. Measurements during the ablation periods since 1992 show an average air temperature for the periods of 2.1°C, an average incoming shorwave radiation of 230W/m2 and an average measured runoff intensity of 14mm/day with a maximum of 68mm/day. Three models of different complexity are tested in order to simulate the water and energy balance of a snow cover on the arctic tundra. The three models are: a complex numerical model (CROCUS), a simple energy balance model and a temperature index model. The simulations were carried out for the melt periods in 1992 and 1996 as these two periods represent very different meteorological conditions. The results of these simulations exposed weaknesses in all the models. The energy balance model lacks calculation of cold content in the snowpack. This influences both the outgoing longwave radiation and the timing of the melt. Due to the effect of compensating errors in the simulations, CROCUS performed better than the simple energy balance model but also this model has problems with the simulation of outgoing longwave radiation. The temperature index model does not perform well for snowmelt studies in regions were radiation is the main driving energy source for the melt.

  6. Balancing Area Coordination: Efficiently Integrating Renewable Energy Into the Grid, Greening the Grid

    SciTech Connect

    Katz, Jessica; Denholm, Paul; Cochran, Jaquelin

    2015-06-01

    Greening the Grid provides technical assistance to energy system planners, regulators, and grid operators to overcome challenges associated with integrating variable renewable energy into the grid. Coordinating balancing area operation can promote more cost and resource efficient integration of variable renewable energy, such as wind and solar, into power systems. This efficiency is achieved by sharing or coordinating balancing resources and operating reserves across larger geographic boundaries.

  7. The Analysis of the Development Dynamics and Structural Balance of Solar Energy in the World

    NASA Astrophysics Data System (ADS)

    Brand, A. E.; Chekardovskiy, S. M.; Akulov, K. A.

    2017-01-01

    The paper presents data the analysis of the development dynamics and structural balance of solar energy in the world. In the article presents information about total installed production capacity of solar energy, the world solar energy production capacity distribution and the European Union energy market structure in 2000 and 2015 years.

  8. Measuring Dark Energy with CHIME

    NASA Astrophysics Data System (ADS)

    Newburgh, Laura; Chime Collaboration

    2015-04-01

    The Canadian Hydrogen Intensity Mapping Experiment (CHIME) is a new radio transit interferometer currently being built at the Dominion Radio Astrophysical Observatory (DRAO) in Penticton, BC, Canada. We will use the 21 cm emission line of neutral hydrogen to map baryon acoustic oscillations between 400-800 MHz across 3/4 of the sky. These measurements will yield sensitive constraints on the dark energy equation of state between redshifts 0.8 - 2.5, a fascinating but poorly probed era corresponding to when dark energy began to impact the expansion history of the Universe. I will describe theCHIME instrument, the analysis challenges, the calibration requirements, and current status.

  9. Munition Mass Properties Measurement Procedures Using a Spin Balance Machine

    DTIC Science & Technology

    2015-03-09

    determines the mass properties, balance configurations, and balance specification(s) of live or inert munitions; namely, the Center of Gravity (CG...the Moment of Inertia (MOI), and the Product of Inertia (POI). 15. SUBJECT TERMS Center of Gravity Product of Inertia Moment of Inertia Spin...B-1 C. CENTER OF GRAVITY ...................................................... C-1 D

  10. Balanced Education Development: Theory, Target and Measuring Methods

    ERIC Educational Resources Information Center

    Zhai, Bo

    2007-01-01

    Educational balance refers to the ideal that educational organizations and people who receive education enjoy equal treatment in educational activities under the thought of fair education and principle of educational equity, and the educational policy as well as legal system that guarantee its actual operations. The essence of balanced education…

  11. Variation in energy balance components from six sites in a native prairie for three years

    NASA Technical Reports Server (NTRS)

    Fritschen, Leo J.; Qian, Ping

    1992-01-01

    Six automatic stations were used to evaluate the surface energy and radiation balances on a native prairie near Manhattan, Kansas, using the Bowen ratio technique for a total of 300 days. Data were taken during the periods from May 26 to October 16, 1987, May 10 to September 18, 1988, and July 21 to August 13, 1989. The station site locations were selected to represent burned and unburned treatments on ridges, valley bottoms, and slopes with various aspects. The measured variables were (1) air and wet bulb temperatures at two heights, (2) net radiation, (3) solar radiation (up and down), (4) total hemispherical radiation (up and down), (5) diffuse radiation, (6) soil heat flow and soil temperature, (7) wind speed, (8) wind direction, and (9) precipitation. Energy balance components at the sites were compared for the 3 years. The variation between sites and years was small, even though some sites were as much as 10 km apart and the years had different rainfall amounts. The average values for the four summer intensive field campaigns (IFCs) were as follows: albedo, 0.2; ratio of net radiation to solar radiation, 62 percent; evaporation equivalent, 4 mm/d; Bowen ratio, 0.32; evaporation fraction, 70 percent; and the ratio of evaporation to solar energy, 40 percent. These values were different for the fall IFC. The latent and sensible heat fluxes were more variable than the radiation terms reflecting soil moisture differences between IFCs.

  12. Enthalpy By Energy Balance for Aerodynamic Heating Facility at NASA Ames Research Center Arc Jet Complex

    NASA Technical Reports Server (NTRS)

    Hightower, T. Mark; MacDonald, Christine L.; Martinez, Edward R.; Balboni, John A.; Anderson, Karl F.; Arnold, Jim O. (Technical Monitor)

    2002-01-01

    The NASA Ames Research Center (ARC) Arc Jet Facilities' Aerodynamic Heating Facility (AHF) has been instrumented for the Enthalpy By Energy Balance (EB2) method. Diagnostic EB2 data is routinely taken for all AHF runs. This paper provides an overview of the EB2 method implemented in the AHF. The chief advantage of the AHF implementation over earlier versions is the non-intrusiveness of the instruments used. For example, to measure the change in cooling water temperature, thin film 1000 ohm Resistance Temperature Detectors (RTDs) are used with an Anderson Current Loop (ACL) as the signal conditioner. The ACL with 1000 ohm RTDs allows for very sensitive measurement of the increase in temperature (Delta T) of the cooling water to the arc heater, which is a critical element of the EB2 method. Cooling water flow rates are measured with non-intrusive ultrasonic flow meters.

  13. Open dissipative seismic systems and ensembles of strong earthquakes: energy balance and entropy funnels

    NASA Astrophysics Data System (ADS)

    Akopian, Samvel Ts.

    2015-06-01

    A concept of seismic system (SS), which is responsible for the preparation of an ensemble of strong earthquakes, is considered as an open dissipative system exchanging energy and entropy with the environment. Open dissipative SS allow one to describe the equilibrium and non-equilibrium states of SS, and the lithosphere evolution under different plate tectonic settings on the basis of seismostatistics. Several new seismic parameters (`seismic temperature', `seismic time', dissipation function, efficiency, inelastic energy, dynamical probability) are defined and proposed for better understanding and describing the dynamical processes. The Sakhalin SS is considered to illustrate the behaviour of proposed parameters. By analogy to Liouville's equation in thermodynamics, it is shown that there is no criterion of instability in the domain where the Gutenberg-Richter law is true. In the proposed approach, the instability origination and the formation of seismogenic structures in the lithosphere are based on the energy versus information entropy power law; the existence of `time arrow' also proceeds from such a dependence. Application of energy and trajectory diagrams enables to describe the preparation of strong earthquakes within an ensemble in terms of slow and fast timescales. These diagrams help perform the spatiotemporal-energy monitoring of the instability origination in the lithosphere. It is shown that the information entropy parameter can serve as a measure of the unknown external energy flow into the system (this energy is supplied for the elastic radiation energy in the earthquake sources and for inelastic processes in the system volume). The property of the ensemble of strong earthquakes is periodically to restore the SS equilibrium state that enables to describe the SS energy balance. The results offer possibilities to estimate the fraction of inelastic energy released by the SS medium during the preparation and occurrence of seismic catastrophes. The

  14. The role of willow-birch forest in the surface energy balance at arctic treeline

    SciTech Connect

    Blanken, P.D. ); Rouse, W.R. )

    1994-11-01

    Continuous measurements of the energy balance components were made during the 1991 growing season over a willow-birch forest located near Churchill, Manitoba, Canada. On the basis of measurements of leaf area index, the growing season was divided into three distinct periods: growth, mature, and senescence. Changes in surface albedo were strongly correlated with changing leaf area index during the growth period with albedo increasing as leaf area increased. The latent heat flux density, Q[sub E], represented 74% of net radiation during the mature period compared to 55 and 54% during the growth and senescence periods, respectively. The greater Q[sub E] at plant maturity is due primarily to canopy transpiration. The sensitivity of Q[sub E] to net radiation was largest during the growth period. In contrast, the sensitivity of Q[sub E] to the surface resistance and aerodynamic resistance was the largest during the mature period. The implications of climate variability on the timing of leaf development and the surface energy and water balance are discussed. 28 refs., 8 figs., 1 tab.

  15. 1st International Symposium on Gait and Balance in MS: Gait and Balance Measures in the Evaluation of People with MS

    PubMed Central

    Cameron, Michelle; Wagner, Joanne; Zackowski, Kathleen; Spain, Rebecca

    2012-01-01

    Gait and balance measures have particular potential as outcome measures in Multiple Sclerosis (MS) because, of the many hallmarks of MS disability, gait and balance dysfunction are present throughout the course of the disease, impact many aspects of a person's life, and progress over time. To highlight the importance and relevance of gait and balance measures in MS, explore novel measurements of gait and balance in MS, and discuss how gait, balance, and fall measures can best be used and developed in clinical and research settings, the 1st International Symposium on Gait and Balance in Multiple Sclerosis was held in Portland, Oregon, USA on October 1, 2011. This meeting brought together nearly 100 neurologists, physiatrists, physical therapists, occupational therapists, nurses, engineers, and others to discuss the current status and recent advances in the measurement of gait and balance in MS. Presentations focused on clinician-administered, self-administered, and instrumented measures of gait, balance, and falls in MS. PMID:22762000

  16. Evapotranspiration dynamics in a boreal peatland and its impact on the water and energy balance

    NASA Astrophysics Data System (ADS)

    Wu, Jiabing; Kutzbach, Lars; Jager, Daniel; Wille, Christian; Wilmking, Martin

    2010-12-01

    Hydrological conditions play a key role in the carbon cycle of northern peatlands. This study examines the evapotranspiration (ET) dynamics and its impact on the water and energy balance in response to differing meteorological conditions during the exceptionally dry year 2006 and the normal wet year 2007 at a boreal peatland in Finland. Energy and water vapor fluxes were determined continuously using the eddy covariance approach. Daily ET rates varied considerably during the growing season and averaged 2.23 ± 0.15 mm d-1 and 1.59 ± 0.07 mm d-1 in the dry and wet year, respectively. Synoptic weather conditions as reflected by incoming radiation and water vapor pressure deficit (VPD) were the key factors controlling ET. Differences in the precipitation patterns and summer temperature also accounted for some of the observed differences in ET between the 2 years. No evidence was found for a relationship between ET rates and water table level, probably due to the relatively high water table level even in the dry year. Latent heat flux dominated the energy balance, particularly in the dry year 2006 with 60% of cumulative precipitation returned to the atmosphere through ET. In the wet year 2007, runoff dominated the water loss, and only 36% of the cumulative precipitation was returned to the atmosphere through ET. While the annual water balance regime of the peatland was mainly regulated by the precipitation pattern, daily measured ET was closely related to potential evaporation, and latent heat flux could be well modeled by the Penman-Monteith approach, suggesting two feasible schemes for ET prediction in peatlands under well watered conditions.

  17. Trends in Research on Energy Balance Supported by the National Cancer Institute

    PubMed Central

    Ballard-Barbash, Rachel; Siddiqi, Sameer M.; Berrigan, David A.; Ross, Sharon A.; Nebeling, Linda C.; Dowling, Emily C.

    2013-01-01

    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. PMID:23498109

  18. Energy Crops and their Implications on Soil Carbon Sequestration, Surface Energy and Water Balance

    NASA Astrophysics Data System (ADS)

    Song, Y.; Barman, R.; Jain, A. K.

    2011-12-01

    The quest to meet growing energy demand with low greenhouse gas emissions has increased attention on the potential of existing and advanced biomass energy crops. Potential energy crops include row crops such as corn, and perennial grasses such as switchgrass. However, a massive expansion of bioenergy crops raises many questions such as: how and where to grow energy crops; and what will be the impacts of growing large scale biofuel crops on the terrestrial hydrological cycle, the surface energy budget, soil carbon sequestration and the concurrent effects on the climate system. An integrated modeling system is being developed with in the framework of a land surface model, the Integrated Science Assessment Model (ISAM), and being applied to address these questions.This framework accounts for the biophysical, physiological and biogeochemical systems governing important processes that regulate crop growth including water, energy and nutrient cycles within the soil-plant-atmosphere system. One row crop (Corn) and two energy crops (Switchgrass and Miscanthus) are studied in current framework. Dynamic phenology processes and parameters for simulating each crop have been developed using observed data from a north to south gradient of field trial sites. This study will specifically focus on the agricultural regions in the US and in Europe. The potential productivity of these three crops will be assessed in terms of carbon sequestration, surface energy and water balance and their spatial variability. This study will help to quantify the importance of various environmental aspects towards modeling bioenergy crops and to better understand the spatial and temporal dynamics of bioenergy crop yields.

  19. Mass balance, energy and exergy analysis of bio-oil production by fast pyrolysis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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 ...

  20. Evaluating surface energy balance system (SEBS) using aircraft data collected during BEAREX07

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Evapotranspiration (ET) is an essential component of the water balance and a major consumptive use of irrigation water and precipitation on cropland. Remote sensing based surface energy balance algorithms are now capable of providing accurate estimates of spatial-temporal ET. Uses of these spatial E...

  1. Effect of milking frequency and diet on milk production, energy balance, and reproduction in dairy cows.

    PubMed

    Patton, J; Kenny, D A; Mee, J F; O'Mara, F P; Wathes, D C; Cook, M; Murphy, J J

    2006-05-01

    The objective of this study was to determine the effects of reduced milking frequency and increased dietary energy density in early lactation on milk production, energy balance, and subsequent fertility. Sixty-six spring-calving, multiparous Holstein-Friesian cows were assigned to 1 of 3 treatment groups: once-daily milking on a standard diet (1xST); 3-times daily milking on a standard diet (3xST); and 3-times daily milking on a high-energy diet. Treatments were imposed for the first 28 d of lactation, after which all groups were milked twice daily and fed the standard diet. During the treatment period, the 1xST cows had 19.6% lower milk yield and higher milk fat and milk protein concentrations (15.7 and 10.2%, respectively) compared with 3xST. Dry matter (DM) intake was similar between 1xST and 3xST during the treatment period (12.64 vs. 13.25 kg/ d; SED = 0.82). Daily energy balance was less negative for 1xST compared with 3xST during wk 1 to 3 of lactation [-3.92 vs. -5.30 unité fourragère lait (UFL)/d; SED = 0.65; 1 UFL is equal to the net energy for lactation of 1 kg of standard air-dry barley]. During the treatment period, the cows on the high-energy diet had 17% higher milk yield, higher DM intake (15.5 vs. 13.9 kg/d; SED = 0.71), and similar energy balance (-4.45 vs. -4.35 UFL/d; SED = 0.65) compared to 3xST. Diet had no significant effect on any of the fertility variables measured. The interval to first ovulation was shorter for 1xST than 3xST (18.3d vs. 28.6d; SED = 1.76). In conclusion, once-daily milking in early lactation may promote earlier resumption of ovarian cyclicity, mediated through improved nutritional status.

  2. Consequences of inadequate food energy and negative energy balance in humans.

    PubMed

    Kurpad, A V; Muthayya, S; Vaz, M

    2005-10-01

    Energy deficiency is probably best measured in adults by the body mass index (BMI). Acute energy deficiency (AED) is associated with body weight loss, along with changes in body composition, as well as a reduced BMR and physical activity. Chronic energy deficiency (CED) is an inadequacy in food to which individuals adapt, at some cost. Individuals with this have never 'lost' weight: they have simply grown less. They adapt to the decreased food energy by reductions in their total energy expenditure (TEE), linked mainly to a lower body size, and to their physical activity. It seems unlikely that enhanced metabolic efficiency contributes substantially to energy saving in CED. Supplementation of energy deficient individuals is accompanied by significant fat deposition; this may have deleterious consequences. Women in many developing countries achieve a successful outcome to pregnancy in spite of being chronically undernourished. Reductions in basal metabolism and behavioural changes in the form of diminished physical activity could meet most of the extra energy needed for pregnancy. Milk energy output is maintained within the expected range in undernourished lactating mothers. Energy deficiency in children is best measured by height-for-age for stunting, and weight-for-height for wasting. Deficits in behavioural and functional parameters in children exist with undernutrition, and can be reduced by early nutritional supplementation along with the appropriate environment.

  3. Two-source energy balance model estimates of evapotranspiration using component and composite surface temperatures

    NASA Astrophysics Data System (ADS)

    Colaizzi, Paul D.; Kustas, William P.; Anderson, Martha C.; Agam, Nurit; Tolk, Judy A.; Evett, Steven R.; Howell, Terry A.; Gowda, Prasanna H.; O'Shaughnessy, Susan A.

    2012-12-01

    The two source energy balance model (TSEB) can estimate evaporation (E), transpiration (T), and evapotranspiration (ET) of vegetated surfaces, which has important applications in water resources management for irrigated crops. The TSEB requires soil (TS) and canopy (TC) surface temperatures to solve the energy budgets of these layers separately. Operationally, usually only composite surface temperature (TR) measurements are available at a single view angle. For surfaces with nonrandom spatial distribution of vegetation such as row crops, TR often includes both soil and vegetation, which may have vastly different temperatures. Therefore, TS and TC must be derived from a single TR measurement using simple linear mixing, where an initial estimate of TC is calculated, and the temperature - resistance network is solved iteratively until energy balance closure is reached. Two versions of the TSEB were evaluated, where a single TR measurement was used (TSEB-TR) and separate measurements of TS and TC were used (TSEB-TC-TS). All surface temperatures (TS, TC, and TR) were measured by stationary infrared thermometers that viewed an irrigated cotton (Gossypium hirsutum L.) crop. The TSEB-TR version used a Penman-Monteith approximation for TC, rather than the Priestley-Taylor-based formulation used in the original TSEB version, because this has been found to result in more accurate partitioning of E and T under conditions of strong advection. Calculations of E, T, and ET by both model versions were compared with measurements using microlysimeters, sap flow gauges, and large monolythic weighing lysimeters, respectively. The TSEB-TR version resulted in similar overall agreement with the TSEB-TC-TS version for calculated and measured E (RMSE = 0.7 mm d-1) and better overall agreement for T (RMSE = 0.9 vs. 1.9 mm d-1), and ET (RMSE = 0.6 vs. 1.1 mm d-1). The TSEB-TC-TS version calculated daily ET up to 1.6 mm d-1 (15%) less early in the season and up to 2.0 mm d-1 (44%) greater

  4. Bacterial proteostasis balances energy and chaperone utilization efficiently.

    PubMed

    Santra, Mantu; Farrell, Daniel W; Dill, Ken A

    2017-03-28

    Chaperones are protein complexes that help to fold and disaggregate a cell's proteins. It is not understood how four major chaperone systems of Escherichia coli work together in proteostasis: the recognition, sorting, folding, and disaggregating of the cell's many different proteins. Here, we model this machine. We combine extensive data on chaperoning, folding, and aggregation rates with expression levels of proteins and chaperones measured at different growth rates. We find that the proteostasis machine recognizes and sorts a client protein based on two biophysical properties of the client's misfolded state (M state): its stability and its kinetic accessibility from its unfolded state (U state). The machine is energy-efficient (the sickest proteins use the most ATP-expensive chaperones), comprehensive (it can handle any type of protein), and economical (the chaperone concentrations are just high enough to keep the whole proteome folded and disaggregated but no higher). The cell needs higher chaperone levels in two situations: fast growth (when protein production rates are high) and very slow growth (to mitigate the effects of protein degradation). This type of model complements experimental knowledge by showing how the various chaperones work together to achieve the broad folding and disaggregation needs of the cell.

  5. Bacterial proteostasis balances energy and chaperone utilization efficiently

    PubMed Central

    Santra, Mantu; Farrell, Daniel W.; Dill, Ken A.

    2017-01-01

    Chaperones are protein complexes that help to fold and disaggregate a cell’s proteins. It is not understood how four major chaperone systems of Escherichia coli work together in proteostasis: the recognition, sorting, folding, and disaggregating of the cell’s many different proteins. Here, we model this machine. We combine extensive data on chaperoning, folding, and aggregation rates with expression levels of proteins and chaperones measured at different growth rates. We find that the proteostasis machine recognizes and sorts a client protein based on two biophysical properties of the client’s misfolded state (M state): its stability and its kinetic accessibility from its unfolded state (U state). The machine is energy-efficient (the sickest proteins use the most ATP-expensive chaperones), comprehensive (it can handle any type of protein), and economical (the chaperone concentrations are just high enough to keep the whole proteome folded and disaggregated but no higher). The cell needs higher chaperone levels in two situations: fast growth (when protein production rates are high) and very slow growth (to mitigate the effects of protein degradation). This type of model complements experimental knowledge by showing how the various chaperones work together to achieve the broad folding and disaggregation needs of the cell. PMID:28292901

  6. Subcellular energy balance of Odontesthes bonariensis exposed to a glyphosate-based herbicide.

    PubMed

    Menéndez-Helman, Renata J; Miranda, Leandro A; Dos Santos Afonso, Maria; Salibián, Alfredo

    2015-04-01

    Water pollution by agrochemicals is currently one of the most critical problems for the conservation of aquatic ecosystems. Glyphosate [N-(phosphonomethyl) glycine); PMG] is the main broad-spectrum post emergence herbicide used for the control of a wide range of pests in soybean crops. Adenylate energy charge (AEC) reflects the energy balance of the cells, a measure of the energy available from the adenylate pool: adenosine triphosphate (ATP), adenosine diphosphate (ADP) and adenosine monophosphate (AMP). Background adenylates, phosphagens and the AEC index of two year old Odontesthes bonariensis were determined in some tissues by HPLC, and the impact on subcellular energy balance of sublethal glyphosate-based herbicide exposure was analyzed. The doses used were 0 (control tank), 1 or 10mg PMGL(-1), trials were carried out during 15 days. AEC values in brain, liver and muscle from control fish were 0.37 ± 0.02, 0.49 ± 0.05 and 0.56 ± 0.03, respectively (means ± SEM). While brain ATP concentrations were undetectable (hence low values of AEC), the muscle tissue showed the highest concentrations of the more energetic molecules: 0.18 μmole ATP g(-1) and 8 μmole phosphocreatine g(-1) (PCrg(-1)). In the brain, no significant changes were detected in exposed fish compared to controls. Instead, in both the liver and muscle of animals exposed to the highest concentration of the herbicide, significant changes in the AEC (reduction of 26% and 15%, p<0.05) with respect to the control group were determined. Chronic exposure (15 days) of Odontesthes bonariensis to 1 and 10mgL(-1) of formulated glyphosate did not affect brain AEC. However, the highest concentration of the herbicide produced a significant decrease in liver and muscle AEC manifesting adverse sublethal effects on the energy metabolism. These results suggest the usefulness of AEC as a biomarker of fish glyphosate exposure.

  7. Developmental programming of energy balance regulation: Is physical activity more "programmable" than food intake

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  8. To ingest or rest? Specialized roles of lateral hypothalamic area neurons in coordinating energy balance

    PubMed Central

    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. PMID:25741247

  9. Water and energy balances in the soil-plant atmosphere continuum

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Energy fluxes at soil-atmosphere and plant-atmosphere interfaces can be summed to zero because the surfaces have no capacity for energy storage. The resulting energy balance equations may be written in terms of physical descriptions of these fluxes; and have been the basis for problem casting and so...

  10. Mapping surface energy balance components by combining landsat thematic mapper and ground-based meteorological data

    USGS Publications Warehouse

    Moran, M.S.; Jackson, R. D.; Raymond, L.H.; Gay, L.W.; Slater, P.N.

    1989-01-01

    Surface energy balance components were evaluated by combining satellite-based spectral data with on-site measurements of solar irradiance, air temperature, wind speed, and vapor pressure. Maps of latent heat flux density (??E) and net radiant flux density (Rn) were produced using Landsat Thematic Mapper (TM) data for three dates: 23 July 1985, 5 April 1986, and 24 June 1986. On each date, a Bowen-ratio apparatus, located in a vegetated field, was used to measure ??E and Rn at a point within the field. Estimates of ??E and Rn were also obtained using radiometers aboard an aircraft flown at 150 m above ground level. The TM-based estimates differed from the Bowen-ratio and aircraft-based estimates by less than 12 % over mature fields of cotton, wheat, and alfalfa, where ??E and Rn ranged from 400 to 700 Wm-2. ?? 1989.

  11. Understanding gas-surface interactions from direct force measurements using a specialized torsion balance

    NASA Technical Reports Server (NTRS)

    Cook, S. R.; Hoffbauer, M. A.

    1996-01-01

    The first comprehensive measurements of the magnitude and direction of the forces exerted on surfaces by molecular beams are discussed and used to obtain information about the microscopic properties of the gas-surface interactions. This unique approach is not based on microscopic measurements of the scattered molecules. The reduced force coefficients are introduced as a new set of parameters that completely describe the macroscopic average momentum transfer to a surface by an incident molecular beam. By using a specialized torsion balance and molecular beams of N2, CO, CO2, and H2, the reduced force coefficients are determined from direct measurements of the force components exerted on surface of a solar panel array material, Kapton, SiO2-coated Kapton, and Z-93 as a function of the angle of incidence ranging from 0 degrees to 85 degrees. The absolute flux densities of the molecular beams were measured using a different torsion balance with a beam-stop that nullified the force of the scattered molecules. Standard time-of-flight techniques were used to determine the flux-weighted average velocities of the various molecular beams ranging from 1600 m/s to 4600 m/s. The reduced force coefficients can be used to directly obtain macroscopic average properties of the scattered molecules, such as the flux-weighted average velocity and translational energy, that can then be used to determine microscopic details concerning gas-surface interactions without the complications associated with averaging microscopic measurements.

  12. Phenotypic vulnerability of energy balance responses to sleep loss in healthy adults

    PubMed Central

    Spaeth, Andrea M.; Dinges, David F.; Goel, Namni

    2015-01-01

    Short sleep duration is a risk factor for increased hunger and caloric intake, late-night eating, attenuated fat loss when dieting, and for weight gain and obesity. It is unknown whether altered energy-balance responses to sleep loss are stable (phenotypic) over time, and the extent to which individuals differ in vulnerability to such responses. Healthy adults experienced two laboratory exposures to sleep restriction separated by 60–2132 days. Caloric intake, meal timing and weight were objectively measured. Although there were substantial phenotypic differences among participants in weight gain, increased caloric intake, and late-night eating and fat intake, responses within participants showed stability across sleep restriction exposures. Weight change was consistent in both normal-weight and overweight adults. Weight change and increased caloric intake were more stable in men whereas late-night eating was consistent in both genders. This is the first evidence of phenotypic differential vulnerability and trait-like stability of energy balance responses to repeated sleep restriction, underscoring the need for biomarkers and countermeasures to predict and mitigate this vulnerability. PMID:26446681

  13. The greenhouse gas and energy balance of different treatment concepts for bio-waste.

    PubMed

    Ortner, Maria E; Müller, Wolfgang; Bockreis, Anke

    2013-10-01

    The greenhouse gas (GHG) and energy performance of bio-waste treatment plants been investigated for three characteristic bio-waste treatment concepts: composting; biological drying for the production of biomass fuel fractions; and anaerobic digestion. Compared with other studies about the environmental impacts of bio-waste management, this study focused on the direct comparison of the latest process concepts and state-of-the-art emission control measures. To enable a comparison, the mass balance and products were modelled for all process concepts assuming the same bio-waste amounts and properties. In addition, the value of compost as a soil improver was included in the evaluation, using straw as a reference system. This aspect has rarely been accounted for in other studies. The study is based on data from operational facilities combined with literature data. The results show that all three concepts contribute to a reduction of GHG emissions and show a positive balance for cumulated energy demand. However, in contrast to other studies, the advantage of anaerobic digestion compared with composting is smaller as a result of accounting for the soil improving properties of compost. Still, anaerobic digestion is the environmentally superior solution. The results are intended to inform decision makers about the relevant aspects of bio-waste treatment regarding the environmental impacts of different bio-waste management strategies.

  14. Energy balance and plume dynamics in Triton's lower atmosphere

    SciTech Connect

    Yelle, R.V.; Lunine, J.I.; Hunten, D.M. )

    1991-02-01

    The present study of the thermal balance-affecting relationships among Triton lower atmosphere thermal conduction, eddy mixing, condensation, and radiative heating indicates that, while the temperature gradient is negative in the lower atmosphere, it becomes positive at higher altitudes due to the downward conduction of ionospheric heat. This temperature profile is essentially consistent with radio-occultation experiment data; the geyser-like plumes observed by Voyager suggest that the Trioton atmosphere's convective and conductive regions join near 10-km altitude, and that the values inferred for the eddy diffusion and heat-transport coefficients indicate a profile reminiscent of the earth's. 28 refs.

  15. The surface energy balance of a polygonal tundra site in northern Siberia - Part 1: Spring to fall

    NASA Astrophysics Data System (ADS)

    Langer, M.; Westermann, S.; Muster, S.; Piel, K.; Boike, J.

    2011-03-01

    In this article, we present a study on the surface energy balance of a polygonal tundra landscape in northeast Siberia. The study was performed during half-year periods from April to September in each of 2007 and 2008. The surface energy balance is obtained from independent measurements of the net radiation, the turbulent heat fluxes, and the ground heat flux at several sites. Short-wave radiation is the dominant factor controlling the magnitude of all the other components of the surface energy balance during the entire observation period. About 50% of the available net radiation is consumed by the latent heat flux, while the sensible and the ground heat flux are each around 20 to 30%. The ground heat flux is mainly consumed by active layer thawing. About 60% of the energy storage in the ground is attributed to the phase change of soil water. The remainder is used for soil warming down to a depth of 15 m. In particular, the controlling factors for the surface energy partitioning are snow cover, cloud cover, and the temperature gradient in the soil. The thin snow cover melts within a few days, during which the equivalent of about 20% of the snow-water evaporates or sublimates. Surface temperature differences of the heterogeneous landscape indicate spatial variabilities of sensible and latent heat fluxes, which are verified by measurements. However, spatial differences in the partitioning between sensible and latent heat flux are only measured during conditions of high radiative forcing, which only occur occasionally.

  16. On the energy balance closure and net radiation in complex terrain

    PubMed Central

    Wohlfahrt, Georg; Hammerle, Albin; Niedrist, Georg; Scholz, Katharina; Tomelleri, Enrico; Zhao, Peng

    2017-01-01

    In complex, sloping terrain, horizontal measurements of net radiation are not reflective of the radiative energy available for the conductive and convective heat exchange of the underlying surface. Using data from a grassland site on a mountain slope characterised by spatial heterogeneity in inclination and aspect, we tested the hypothesis that a correction of the horizontal net radiation measurements which accounts for the individual footprint contributions of the various surfaces to the measured sensible and latent heat eddy covariance fluxes will yield more realistic slope-parallel net radiation estimates compared to a correction based on the average inclination and aspect of the footprint. Our main result is that both approaches led to clear, but very similar improvements in the phase between available energy and the sum of the latent and sensible heat fluxes. As a consequence the variance in the sum of latent and sensible heat flux explained by available radiation improved by >10 %, while energy balance closure improved only slightly. This is shown to be mainly due to the average inclination and aspect corresponding largely with the inclination and aspect of the main flux source area in combination with a limited sensitivity of the slope correction to small angular differences in, particularly, inclination and aspect. We conclude with a discussion of limitations of the present approach and future research directions. PMID:28066093

  17. On the Linearly-Balanced Kinetic Energy Spectrum

    NASA Technical Reports Server (NTRS)

    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.

  18. The fluctuation energy balance in non-suspended fluid-mediated particle transport

    SciTech Connect

    Pähtz, Thomas; Durán, Orencio; Ho, Tuan-Duc; Valance, Alexandre; Kok, Jasper F.

    2015-01-15

    Here, we compare two extreme regimes of non-suspended fluid-mediated particle transport, transport in light and heavy fluids (“saltation” and “bedload,” respectively), regarding their particle fluctuation energy balance. From direct numerical simulations, we surprisingly find that the ratio between collisional and fluid drag dissipation of fluctuation energy is significantly larger in saltation than in bedload, even though the contribution of interparticle collisions to transport of momentum and energy is much smaller in saltation due to the low concentration of particles in the transport layer. We conclude that the much higher frequency of high-energy particle-bed impacts (“splash”) in saltation is the cause for this counter-intuitive behavior. Moreover, from a comparison of these simulations to particle tracking velocimetry measurements which we performed in a wind tunnel under steady transport of fine and coarse sand, we find that turbulent fluctuations of the flow produce particle fluctuation energy at an unexpectedly high rate in saltation even under conditions for which the effects of turbulence are usually believed to be small.

  19. The ANIBES Study on Energy Balance in Spain: Design, Protocol and Methodology

    PubMed Central

    Ruiz, Emma; Ávila, José Manuel; Castillo, Adrián; Valero, Teresa; del Pozo, Susana; Rodriguez, Paula; Bartrina, Javier Aranceta; Gil, Ángel; González-Gross, Marcela; Ortega, Rosa M.; Serra-Majem, Lluis; Varela-Moreiras, Gregorio

    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”) Study was to carry out an accurate updating of food and beverage intake, dietary habits/behaviour and anthropometric data of the Spanish population (9–75 years, n = 2009), as well as the energy expenditure and physical activity patterns. Anthropometry measurements (weight, height, body mass index, waist circumference, % body fat, % body water) were obtained; diet was evaluated throughout a three-day dietary record (tablet device) accompanied by a 24 h-dietary recall; physical activity was quantified by questionnaire and accelerometers were also employed. Finally, information about perception and understanding of several issues related to EB was also obtained. The ANIBES study will contribute to provide valuable useful data to inform food policy planning, food based dietary guidelines development and other health oriented actions in Spain. PMID:25658237

  20. Analysis of climate change impacts on surface energy balance of Lake Huron (estimation of surface energy balance components: Remote sensing approach for water -- atmosphere parameterization)

    NASA Astrophysics Data System (ADS)

    Petchprayoon, Pakorn

    The purpose of this thesis was to investigate the physical processes of energy exchange between the water surface and atmosphere of Lake Huron in order to explain the processes behind such changes in long-term water levels and to monitor their spatial and temporal fluctuations. The lake surface water temperature and the four components of surface energy balance, including net radiation, latent heat, sensible heat, and heat storage, as well as evaporation rate, were estimated using the daily remotely sensed data from eleven years (2002--2012) with a multi-spatial resolution of 1 km to 5 km using the Moderate Resolution Imaging Spectroradiometer (MODIS) on board Terra satellite, together with in-situ measurements. The regression analysis of the entire lake daily mean water surface temperature revealed a positive trend of 0.1 °C per year, indicating that the lake surface temperature increased by 1.1°C during the period 2002-2012. The warming rate was found to be greatest in the deepest areas of the lake, with a statistically-significant correlation between warming rate and depth. The four components of surface energy balance showed temporal and spatial heterogeneities. There were strong seasonal patterns for all of the components, which were very high in summer and low in winter for net radiation and heat storage. In contrast, the latent heat and sensible heat were very high in the winter and very low in the summer. Approximately 70% of the annual mean 30 min evaporation occurred during the fall and winter seasons, whereas the lowest evaporation rate occurred in March, which was only 3% of the annual mean of 30 min evaporation. There was an increase in the evaporation rate of approximately 1.4 mm m-2 over the 2005--2012 observation period, the water level decreased by 0.04 m during the period 2002--2012, and there was a decrease in total water storage by 1.18 cm during the entire study period (2004--2012). There was obviously a negative correlation between lake

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

    PubMed Central

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

    2016-01-01

    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. PMID:27057108

  2. Neuronal energy-sensing pathway promotes energy balance by modulating disease tolerance

    PubMed Central

    Shen, Run; Wang, Biao; Giribaldi, Maria G.; Ayres, Janelle; Thomas, John B.; Montminy, Marc

    2016-01-01

    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. PMID:27208092

  3. The effect of cloud type on earth's energy balance - Results for selected regions

    NASA Technical Reports Server (NTRS)

    Ockert-Bell, Maureen E.; Hartmann, Dennis L.

    1992-01-01

    International Satellite Cloud Climatology Project (ISCCP) C1 cloud information is compared with planetary albedo, outgoing longwave radiation (OLR), and net radiation measured at the top of the atmosphere by the Earth Radiation Budget Experiment (ERBE). Principal component analysis indicates that the day-to-day variations of the abundances of the 35 cloud types of the C1 data are correlated with each other, so that for many purposes the data set can be well represented by about five cloud types. Using stepwise multiple regression, the ISCCP C1 data can be used to predict the day-to-day variations of the energy balance measured by ERBE for 2.5-deg regions. Total fractional area coverage of cloudiness is a relatively poor predictor of radiation budget quantities. If the total fractional area coverage by clouds is divided into contributions from several distinct cloud types, the fractional coverages by these several cloud types will together form a much better prediction of radiation budget quantities than the single variable of total fractional-area cloud coverage. The regression equations can be used to estimate the net effect of clouds on the radiation balance and the contributions from particular types of clouds to albedo, OLR, and net radiation.

  4. Acute effects of mustard, horseradish, black pepper and ginger on energy expenditure, appetite, ad libitum energy intake and energy balance in human subjects.

    PubMed

    Gregersen, N T; Belza, A; Jensen, M G; Ritz, C; Bitz, C; Hels, O; Frandsen, E; Mela, D J; Astrup, A

    2013-02-14

    Chilli peppers have been shown to enhance diet-induced thermogenesis (DIT) and reduce energy intake (EI) in some studies, but there are few data on other pungent spices. The primary aim of the present study was to test the acute effects of black pepper (pepper), ginger, horseradish and mustard in a meal on 4 h postprandial DIT. The secondary aim was to examine the effects on subjective appetite measures, ad libitum EI and energy balance. In a five-way placebo-controlled, single-blind, cross-over trial, twenty-two young (age 24·9 (SD 4·6) years), normal-weight (BMI 21·8 (SD 2·1) kg/m²) males were randomly assigned to receive a brunch meal with either pepper (1·3 g), ginger (20 g), horseradish (8·3 g), mustard (21 g) or no spices (placebo). The amounts of spices were chosen from pre-testing to make the meal spicy but palatable. No significant treatment effects were observed on DIT, but mustard produced DIT, which tended to be larger than that of placebo (14 %, 59 (SE 3) v. 52 (SE 2) kJ/h, respectively, P=0·08). No other spice induced thermogenic effects approaching statistical significance. Subjective measures of appetite (P>0·85), ad libitum EI (P=0·63) and energy balance (P=0·67) also did not differ between the treatments. Finally, horseradish decreased heart rate (P=0·048) and increased diastolic blood pressure (P= 0·049) compared with placebo. In conclusion, no reliable treatment effects on appetite, EI or energy balance were observed, although mustard tended to be thermogenic at this dose. Further studies should explore the possible strength and mechanisms of the potential thermogenic effect of mustard actives, and potential enhancement by, for example, combinations with other food components.

  5. Energy balance in the solar transition region. I - Hydrostatic thermal models with ambipolar diffusion

    NASA Technical Reports Server (NTRS)

    Fontenla, J. M.; Avrett, E. H.; Loeser, R.

    1990-01-01

    The energy balance in the lower transition region is analyzed by constructing theoretical models which satisfy the energy balance constraint. The energy balance is achieved by balancing the radiative losses and the energy flowing downward from the corona. This energy flow is mainly in two forms: conductive heat flow and hydrogen ionization energy flow due to ambipolar diffusion. Hydrostatic equilibrium is assumed, and, in a first calculation, local mechanical heating and Joule heating are ignored. In a second model, some mechanical heating compatible with chromospheric energy-balance calculations is introduced. The models are computed for a partial non-LTE approach in which radiation departs strongly from LTE but particles depart from Maxwellian distributions only to first order. The results, which apply to cases where the magnetic field is either absent, or uniform and vertical, are compared with the observed Lyman lines and continuum from the average quiet sun. The approximate agreement suggests that this type of model can roughly explain the observed intensities in a physically meaningful way, assuming only a few free parameters specified as chromospheric boundary conditions.

  6. Data Input, Processing and Presentation. [helicopter rotor balance measurement

    NASA Technical Reports Server (NTRS)

    Langer, H. J.

    1984-01-01

    The problems of data acquisition, processing and display are investigated in the case of a helicopter rotor balance. The types of sensors to be employed are discussed in addition to their placement and application in wind tunnel trials. Finally, the equipment for data processing, evaluation and storage are presented with a description of methods.

  7. Energy Policy Decision-Making: The Need for Balanced Input

    ERIC Educational Resources Information Center

    DeVolpi, A.

    1974-01-01

    Indicates that the credibility of environmentalists and nuclear advocates has been damaged by misinformed alarmist positions. Advocates the public's right of equal standing on advisory councils in the areas of energy development, environmental protection, and public safety. (GS)

  8. Monitoring crop coefficient of orange orchards using energy balance and the remote sensed NDVI

    NASA Astrophysics Data System (ADS)

    Consoli, Simona; Cirelli, Giuseppe Luigi; Toscano, Attilio

    2006-09-01

    The structure of vegetation is paramount in regulating the exchange of mass and energy across the biosphereatmosphere interface. In particular, changes in vegetation density affected the partitioning of incoming solar energy into sensible and latent heat fluxes that may result in persistent drought through reductions in agricultural productivity and in the water resources availability. Limited research with citrus orchards has shown improvements to irrigation scheduling due to better water-use estimation and more appropriate timing of irrigation when crop coefficient (Kc) estimate, derived from remotely sensed multispectral vegetation indices (VIs), are incorporated into irrigation-scheduling algorithms. The purpose of this article is the application of an empirical reflectance-based model for the estimation of Kc and evapotranspiration fluxes (ET) using ground observations on climatic data and high-resolution VIs from ASTER TERRA satellite imagery. The remote sensed Kc data were used in developing the relationship with the normalized difference vegetation index (NDVI) for orange orchards during summer periods. Validation of remote sensed data on ET, Kc and vegetation features was deal through ground data observations and the resolution of the energy balance to derive latent heat flux density (λE), using measures of net radiation (Rn) and soil heat flux density (G) and estimate of sensible heat flux density (H) from high frequency temperature measurements (Surface Renewal technique). The chosen case study is that of an irrigation area covered by orange orchards located in Eastern Sicily, Italy) during the irrigation seasons 2005 and 2006.

  9. Water, ice, and meteorological measurements at South Cascade Glacier, Washington, 1997 balance year

    USGS Publications Warehouse

    Krimmel, Robert M.

    1998-01-01

    Winter snow accumulation and summer snow, firn, and ice melt were measured at South Cascade Glacier, Washington to determine the winter and net balances for the 1997 balance year. The 1997 winter balance, averaged over the glacier, was 3.71 meters, and the net balance was 0.63 meter. The winter balance was the greatest since 1972 (4.27 meters), and the second largest since the record began in 1959. The net balance, which was positive for the second year in a row, was 1.57 meters greater than the 1977-96 average (-0.94 meter). Runoff was measured from the glacier and an adjacent non-glacierized basin. Air temperature and precipitation were measured nearby. This report makes these data available to the glaciological and climatological community.

  10. Combination of snowpack modelling and TLS observations to analyze small scale spatial varaiability of snowpack energy and mass balance

    NASA Astrophysics Data System (ADS)

    Revuelto, Jesús; Vionnet, Vincent; López-Moreno, Juan Ignacio; Lafaysse, Matthieu; Morin, Samuel

    2015-04-01

    Improving the comprehension on how the different energetic balance components affect the snowpack mass balance during the melting period is important from a hydrological point of view. An accurate Snow Water Equivalent (SWE) distribution is needed for this objective, but unfortunately SWE measurement over large areas is not feasible nowadays. This distribution can be provided by a snowpack model but simulations often differ from the real state, because some physical processes are not yet properly modelled. In this study, we take advantage of distributed snowpack simulations corrected throughout the snow season with several snow depth distributions measured with a Terrestrial Laser Scanner (TLS). This allows us to obtain a more realistic SWE evolution and analyse its relations with the snowpack surface energy balance during the melting period considering small scale spatial variability. For 2012, 2013 and 2014 snow seasons several intensive TLS snow depth data acquisitions were accomplished at Izas Experimental catchment; a 52ha study site located in central Spanish Pyrenees with an elevation that ranges between 2050 to 2350m above sea level. The detailed snowpack model Crocus has been used for simulating the snowpack evolution at 5m grid spacing during these three snow seasons, driven by downscaled meteorological fields from the SAFRAN reanalysis. Shadow effects on direct solar radiation are explicitly considered in the snowpack simulation. When a snow depth distribution map measured with the TLS was available, the simulation was stopped and the modelled snow depth distribution was adjusted to match observations. Afterwards the snow simulation was restarted, being subsequently simulated a more realistic snowpack distribution. Considering this improved simulation, the components of the surface energy balance simulated by Crocus were analysed in relation to the simulated mass balance dynamics during the melting period. In such a way a Principal Component Analysis

  11. More quality measures versus measuring what matters: a call for balance and parsimony

    PubMed Central

    Nelson, Eugene C; Pryor, David B; James, Brent; Swensen, Stephen J; Kaplan, Gary S; Weissberg, Jed I; Bisognano, Maureen; Yates, Gary R; Hunt, Gordon C

    2012-01-01

    External groups requiring measures now include public and private payers, regulators, accreditors and others that certify performance levels for consumers, patients and payers. Although benefits have accrued from the growth in quality measurement, the recent explosion in the number of measures threatens to shift resources from improving quality to cover a plethora of quality-performance metrics that may have a limited impact on the things that patients and payers want and need (ie, better outcomes, better care, and lower per capita costs). Here we propose a policy that quality measurement should be: balanced to meet the need of end users to judge quality and cost performance and the need of providers to continuously improve the quality, outcomes and costs of their services; and parsimonious to measure quality, outcomes and costs with appropriate metrics that are selected based on end-user needs. PMID:22893696

  12. 26 CFR 801.1 - Balanced performance measurement system; in general.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 26 Internal Revenue 20 2010-04-01 2010-04-01 false Balanced performance measurement system; in general. 801.1 Section 801.1 Internal Revenue INTERNAL REVENUE SERVICE, DEPARTMENT OF THE TREASURY (CONTINUED) INTERNAL REVENUE PRACTICE BALANCED SYSTEM FOR MEASURING ORGANIZATIONAL AND EMPLOYEE...

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

    PubMed

    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.

  14. Energy balance-dependent regulation of ovine glucose 6-phosphate dehydrogenase protein isoform expression.

    PubMed

    Triantaphyllopoulos, Kostas A; Laliotis, George P; Bizelis, Iosif A

    2014-01-01

    G6PDH is the rate-limiting enzyme of the pentose phosphate pathway and one of the principal source of NADPH, a major cellular reductant. Importantly, in ruminant's metabolism the aforementioned NADPH provided, is utilized for de novo fatty acid synthesis. Previous work of cloning the ovine (Ovis aries) og6pdh gene has revealed the presence of two cDNA transcripts (og6pda and og6pdb), og6pdb being a product of alternative splicing not similar to any other previously reported.(1) In the current study the effect of energy balance in the ovine G6PDH protein expression was investigated, shedding light on the biochemical features and potential physiological role of the oG6PDB isoform. Changes in energy balance leads to protein expression changes in both transcripts, to the opposite direction and not in a proportional way. Negative energy balance was not in favor of the presence of any particular isoform, while both protein expression levels were not significantly different (P > 0.05). In contrast, at the transition point from negative to positive and on the positive energy balance, there is a significant increase of oG6PDA compared with oG6PDB protein expression (P < 0.001). Both oG6PDH protein isoforms changed significantly toward the positive energy balance. oG6PDA is escalating, while oG6PDB is falling, under the same stimulus (positive energy balance alteration). This change is also positively associated with increasing levels in enzyme activity, 4 weeks post-weaning in ewes' adipose tissue. Furthermore, regression analysis clearly demonstrated the linear correlation of both proteins in response to the WPW, while energy balance, enzyme activity, and oG6PDA relative protein expression follow the same escalating trend; in contrast, oG6PDB relative protein expression falls in time, similar to both transcripts accumulation pattern, as reported previously.(2.)

  15. Integration of microalgae systems at municipal wastewater treatment plants: implications for energy and emission balances.

    PubMed

    Menger-Krug, Eve; Niederste-Hollenberg, Jutta; Hillenbrand, Thomas; Hiessl, Harald

    2012-11-06

    Integrating microalgae systems (MAS) at municipal wastewater treatment plants (WWTPs) to produce of bioenergy offers many potential synergies. Improved energy balances provide a strong incentive for WWTPs to integrate MAS, but it is crucial that WWTPs maintain their barrier function to protect water resources. We perform a prospective analysis of energy and emission balances of a WWTP with integrated MAS, based on a substance flow analysis of the elements carbon (C), nitrogen (N), and phosphorus (P). These elements are the main ingredients of wastewater, and the key nutrients for algae growth. We propose a process design which relies solely on resources from wastewater with no external input of water, fertilizer or CO(2). The whole process chain, from cultivation to production of bioelectricity, takes place at the WWTP. Our results show that MAS can considerably improve energy balances of WWTPs without any external resource input. With optimistic assumptions, they can turn WWTPs into net energy producers. While intensive C recycling in MAS considerably improves the energy balance, we show that it also impacts on effluent quality. We discuss the importance of nonharvested biomass for effluent quality and highlight harvesting efficiency as key factor for energy and emission balances of MAS at WWTP.

  16. Soil heat flux and day time surface energy balance closure at astronomical observatory, Thiruvananthapuram, south Kerala

    NASA Astrophysics Data System (ADS)

    Roxy, M. S.; Sumithranand, V. B.; Renuka, G.

    2014-06-01

    Soil heat flux is an important input component of surface energy balance. Estimates of soil heat flux were made in the year 2008 using soil temperature data at Astronomical Observatory, Thiruvananthapuram, south Kerala. Hourly values of soil heat flux from 00 to 24 LST are presented for selected days typical of the winter, pre-monsoon, SW monsoon and NE monsoon seasons. The diurnal variation is characterized by a cross-over from negative to positive values at 0700 h, occurrence of maximum around noon and return to negative values in the late evening. The energy storage term for the soil layer 0-0.05 m is calculated and the ground heat flux G ∗ is estimated in all seasons. Daytime surface energy balance at the surface on wet and dry seasons is investigated. The average Bowen's ratio during the wet and dry seasons were 0.541 and 0.515, respectively indicating that considerable evaporation takes place at the surface. The separate energy balance components were examined and the mean surface energy balance closure was found to be 0.742 and 0.795 for wet and dry seasons, respectively. When a new method that accounts for both soil thermal conduction and soil thermal convection was adopted to calculate the surface heat flux, the energy balance closure was found to be improved. Thus on the land surface under study, the soil vertical water movement is significant.

  17. Water and energy balance in a Mediterranean snowpack: the importance of evaposublimation

    NASA Astrophysics Data System (ADS)

    Herrero, Javier; Pimentel, Rafael; María José, Pérez-Palazón; María José, Polo

    2016-04-01

    In low-latitude snowpacks or those located in semiarid regions, snow dynamics becomes an essential driver of the hydrological cycle, as well as an important support for a number of ecosystem services with an influence over the economy and the ecology of the whole region. Therefore, it is crucial to understand the processes that are taking place in the snowpack and the relative importance and timing of the different mass and energy fluxes. Sierra Nevada is a linear mountain range parallel to the Mediterranean coastline of southern Spain at 37°N. It reaches up to 3479 m.a.s.l. in approximately 40 km from the sea. Despite the semiarid climatic conditions that surround the high mountain area, it presents a regular snow cover above 2500 m.a.s.l. during the winter season. Previous studies have shown at this site that this snowpack is very exposed to high insolation rates and strong winds, and, like in other low-latitude areas, the radiative and evaposublimation (combination of the sublimation of ice and the evaporation of the water drops melted on the surface of the snow) fluxes may have a significant and prominent value in the coupled balance. In this work, we study the evaposublimation fraction in the annual water and energy balance over the snowpack in Sierra Nevada. For this, we apply a one-layer mass and energy balance snow model developed in previous works, which has proven to adequately simulate the shallow snowpacks of Sierra Nevada during the year. High evaposublimation rates were simulated and subsequently measured during several field campaigns. Evaposublimation fractions were found to range from 24 to 33% of the total annual ablation at this site. This ratio is very changeable between years, like the local meteorology itself, even though there was not a direct relationship between this rate and the dry or humid nature of each particular year. In fact, it is the particular distribution of the rainfall throughout the year what defines the dynamics of the

  18. Fuel feeds function: Energy balance and bovine peripheral blood mononuclear cell activation.

    PubMed

    Schwarm, A; Viergutz, T; Kuhla, B; Hammon, H M; Schweigel-Röntgen, M

    2013-01-01

    A general phenomenon in peripartum mammals is the breakdown of (acquired) immunity. The incidence of parasite load, disease and inflammation often rise during the specific energetically demanding time of pregnancy and lactation. In this period, blood leukocytes display decreased DNA synthesis in response to mitogens in vitro. Leukocyte activation, the phase of the cell cycle preceding the DNA synthetic phase has hardly been investigated, but the few studies suggest that leukocyte activation may also be impaired by the limited energy/nutrient availability. Leukocyte activation is characterized by manifold processes, thus, we used the cellular oxygen consumption rate (OCR) as a measure of ATP turnover to support all these processes. We hypothesized that the activation of peripheral blood mononuclear cells (PBMC) - in terms of oxygen consumed over basal levels after in vitro stimulation - is altered by energy balance around parturition. We studied peripartum high-yielding dairy cows because they undergo substantial fluctuations in energy intake, energy output and body fat mass. We established a fluorescence-based test strategy allowing for long-term (≥24h) quantification of O(2)-consumption and studied the peripartum period from 5 weeks ante partum to 5 weeks postpartum. In addition, we determined cellular lactate production, DNA/RNA synthesis and cell size and zoo-technical parameters such as animal energy intake and milk yield were assessed, as well as selected plasma parameters, e.g. glucose concentration. The basal OCR of PBMC from pregnant, non-lactating cows (n=6, -5 weeks ante partum) was 1.19±0.15 nmol min(-1) (10(7)cells)(-1) and increased to maximum levels of 2.54±0.49 nmol min(-1) (10(7)cells)(-1) in phytohemagglutinin (PHA)-stimulated PBMC. The basal OCR did not change over the peripartum period. Whereas the activation indices, herein defined as the PHA-induced 24h-increase of OCR above baseline, amounted to 1.1±0.3, 4.2±0.3, 4.1±1.1, 2.1±0.3, and

  19. Multiobjective calibration and sensitivity of a distributed land surface water and energy balance model

    NASA Astrophysics Data System (ADS)

    Houser, Paul R.; Gupta, Hoshin V.; Shuttleworth, W. James; Famiglietti, James S.

    2001-12-01

    The feasibility of using spatially distributed information to improve the predictive ability of a spatially distributed land surface water and energy balance model (LSM) was explored at the U.S. Department of Agriculture Agricultural Research Service (USDA-ARS) Walnut Gulch Experimental Watershed in southeastern Arizona. The inclusion of spatially variable soil and vegetation information produced unrealistic simulations that were inconsistent with observations, which was likely an artifact of both discretely assigning a single set of parameters to a given area and inadequate knowledge of spatially varying parameter values. Because some of the model parameters were not measured or are abstract quantities a multiobjective least squares strategy was used to find catchment averaged parameter values that minimize the prediction error of latent heat flux, soil heat flux, and surface soil moisture. This resulted in a substantial improvement in the model's spatially distributed performance and yielded valuable insights into the interaction and optimal selection of model parameters.

  20. The Energy Balance of Corn Ethanol: An Update

    SciTech Connect

    Shapouri, Hosein; Duffield, James A.; Wang, Michael

    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.

  1. Effect of row orientation on energy balance components

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Solar irradiance is the primary source of energy that is converted into sensible and latent heat fluxes in the soil-plant-atmosphere continuum. The orientation of agricultural crop rows relative to the sun’s zenith angle determines the amount of solar irradiance reaching the plant and soil surfaces...

  2. Saving Energy in Historic Buildings: Balancing Efficiency and Value

    ERIC Educational Resources Information Center

    Cluver, John H.; Randall, Brad

    2012-01-01

    By now the slogan of the National Trust for Historic Preservation that "the greenest building is the one already built" is widely known. In an era of increased environmental awareness and rising fuel prices, however, the question is how can historic building stock be made more energy efficient in a manner respectful of its historic…

  3. The Tidal Dynamics and Energy Balance of the Red Sea

    NASA Astrophysics Data System (ADS)

    Pugh, David T.; Abualnaja, Yasser O.; NP, Mohammedali; Eltaib, Elfatih B.

    2014-05-01

    The semidiurnal tides of the Red Sea have been mapped as a classic half-wavelength standing wave. Because of the earth's rotation, the pattern is actually composed of an ingoing Kelvin wave, with maximum amplitude found in the northern eastern side along the Saudi Arabia coastline, and a reflected south-going Kelvin wave along the southern African coastline. The result is tidal rotation around a central amphidrome; this amphidrome, because of energy losses in the reflected wave, is nearer to the African side close to Port Sudan. The movements of this amphidrome can be mapped through a spring-neap tidal cycle to show how the tidal energy is dissipated through the Red Sea. There are suggestions that that Red Sea tides are entirely due to direct internal tidal gravitational astronomical forcing; this is an alternative to the model of energy flux from the Gulf of Aden tides in the Indian Ocean, through the entrance at Bab el Mandeb. These alternative energy sources will be investigated in the project.

  4. Measuring the Impact of Business Rules on Inventory Balancing

    DTIC Science & Technology

    2013-09-01

    value depending on the set of business rules employed. Any cost that remains the same regardless of the balancing policy is not relevant because it...for a given amount of items. For example, replenishment costs depend on the number of procurements. The more the procurements, the higher the...arises as to how much of the forecast depends on the historical demand models and how much on human intervention. To illustrate this distinction, during

  5. Energy Balance and Turbulent Flux Partitioning in a Corn-soybean Rotation in the Midwestern U.S.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Energy balance at soil surface-canopy interface is critical for better understanding of water balance and changes in regional weather patterns; however, limited long-term, year-round studies have been conducted in agricultural fields. This study was carried out to assess energy balance closure and p...

  6. Point measurements of surface mass balance, Eklutna Glacier, Alaska, 2008-2015

    USGS Publications Warehouse

    Sass, Louis; Loso, Michael G; Geck, Jason

    2017-01-01

    This data set consists of a time-series of direct measurements of glacier surface mass balance, at Eklutna Glacier, Alaska. It includes seasonal measurements of winter snow accumulation and summer snow and ice ablation.

  7. Effects of activity and energy budget balancing algorithm on laboratory performance of a fish bioenergetics model

    USGS Publications Warehouse

    Madenjian, Charles P.; David, Solomon R.; Pothoven, Steven A.

    2012-01-01

    We evaluated the performance of the Wisconsin bioenergetics model for lake trout Salvelinus namaycush that were fed ad libitum in laboratory tanks under regimes of low activity and high activity. In addition, we compared model performance under two different model algorithms: (1) balancing the lake trout energy budget on day t based on lake trout energy density on day t and (2) balancing the lake trout energy budget on day t based on lake trout energy density on day t + 1. Results indicated that the model significantly underestimated consumption for both inactive and active lake trout when algorithm 1 was used and that the degree of underestimation was similar for the two activity levels. In contrast, model performance substantially improved when using algorithm 2, as no detectable bias was found in model predictions of consumption for inactive fish and only a slight degree of overestimation was detected for active fish. The energy budget was accurately balanced by using algorithm 2 but not by using algorithm 1. Based on the results of this study, we recommend the use of algorithm 2 to estimate food consumption by fish in the field. Our study results highlight the importance of accurately accounting for changes in fish energy density when balancing the energy budget; furthermore, these results have implications for the science of evaluating fish bioenergetics model performance and for more accurate estimation of food consumption by fish in the field when fish energy density undergoes relatively rapid changes.

  8. Correlations between measures of dynamic balance in individuals with post-stroke hemiparesis.

    PubMed

    Vistamehr, Arian; Kautz, Steven A; Bowden, Mark G; Neptune, Richard R

    2016-02-08

    Mediolateral balance control during walking is a challenging task in post-stroke hemiparetic individuals. To detect and treat dynamic balance disorders, it is important to assess balance using reliable methods. The Berg Balance Scale (BBS), Dynamic Gait Index (DGI), margin-of-stability (MoS), and peak-to-peak range of angular-momentum (H) are some of the most commonly used measures to assess dynamic balance and fall risk in clinical and laboratory settings. However, it is not clear if these measures lead to similar conclusions. Thus, the purpose of this study was to assess dynamic balance in post-stroke hemiparetic individuals using BBS, DGI, MoS and the range of H and determine if these measure are correlated. BBS and DGI were collected from 19 individuals post-stroke. Additionally, kinematic and kinetic data were collected while the same individuals walked at their self-selected speed. MoS and the range of H were calculated in the mediolateral direction for each participant. Correlation analyses revealed moderate associations between all measures. Overall, a higher range of angular-momentum was associated with a higher MoS, wider step width and lower BBS and DGI scores, indicating poor balance control. Further, only the MoS from the paretic foot placement, but not the nonparetic foot, correlated with the other balance measures. Although moderate correlations existed between all the balance measures, these findings do not necessarily advocate the use of a single measure as each test may assess different constructs of dynamic balance. These findings have important implications for the use and interpretation of dynamic balance assessments.

  9. Correlations between Measures of Dynamic Balance in Individuals with Post-stroke Hemiparesis

    PubMed Central

    Vistamehr, Arian; Kautz, Steven A.; Bowden, Mark G.; Neptune, Richard R.

    2016-01-01

    Mediolateral balance control during walking is a challenging task in post-stroke hemiparetic individuals. To detect and treat dynamic balance disorders, it is important to assess balance using reliable methods. The Berg Balance Scale (BBS), Dynamic Gait Index (DGI), margin-of-stability (MoS), and peak-to-peak range of angular-momentum (H) are some of the most commonly used measures to assess dynamic balance and fall risk in clinical and laboratory settings. However, it is not clear if these measures lead to similar conclusions. Thus, the purpose of this study was to assess dynamic balance in post-stroke hemiparetic individuals using BBS, DGI, MoS and the range of H and determine if these measure are correlated. BBS and DGI were collected from 19 individuals post-stroke. Additionally, kinematic and kinetic data were collected while the same individuals walked at their self-selected speed. MoS and the range of H were calculated in the mediolateral direction for each participant. Correlation analyses revealed moderate associations between all measures. Overall, a higher range of angular-momentum was associated with a higher MoS, wider step width and lower BBS and DGI scores, indicating poor balance control. Further, only the MoS from the paretic foot placement, but not the nonparetic foot, correlated with the other balance measures. Although moderate correlations existed between all the balance measures, these findings do not necessarily advocate the use of a single measure as each test may assess different constructs of dynamic balance. These findings have important implications for the use and interpretation of dynamic balance assessments. PMID:26795124

  10. Permafrost and surface energy balance of a polygonal tundra site in northern Siberia - Part 1: Spring to fall

    NASA Astrophysics Data System (ADS)

    Langer, M.; Westermann, S.; Muster, S.; Piel, K.; Boike, J.

    2010-07-01

    Permafrost thawing is essentially determined by the surface energy balance, which potentially triggers the activation of a massive carbon source, if previously frozen organic soils are exposed to microbial decomposition. In this article, we present the first part of a comprehensive annual surface energy balance study performed at a polygonal tundra landscape in northeast Siberia, realized between spring 2007 and winter 2009. This part of the study focuses on the half year period from April to September 2007-2008, during which the surface energy balance is obtained from independent measurements of the radiation budget, the turbulent heat fluxes and the ground heat flux at several sites. The short-wave radiation is the dominant factor in the surface energy balance during the entire observation period. About 50% of the available net radiation is consumed by latent heat flux, while the sensible and the ground heat flux are both on the order of 20 to 30%. The ground heat flux is mainly consumed by active layer thawing, where 60% of soil energy storage are attributed to. The remainder is used for soil warming down to a depth of 15 m. The controlling factors for the surface energy partitioning are in particular the snow cover, the cloud cover and the soil temperature gradient. Significant surface temperature differences of the heterogeneous landscape indicate spatial variabilities of sensible and latent heat fluxes, which are verified by measurements at different locations. However, differences in the partition between sensible and latent heat flux for the different sites only exist during conditions of high radiative forcing, which only occur occasionally.

  11. The relationship between dietary intake, exercise, energy balance and the space craft environment

    NASA Technical Reports Server (NTRS)

    Stein, T. P.

    2000-01-01

    Space flight is associated with the loss of skeletal muscle, principally from muscles with anti-gravity functions. Examination of data across different missions can permit a distinction to be made between true microgravity responses and what are mission-specific responses. Protein metabolism has been investigated on six missions, four short-term [Shuttle missions Space Life Sciences 1 (1991, SLSI), Space Life Sciences 2 (1993, SLS2), Deutsche-2 (1993, D2) and the Life and Microgravity Sciences (1996, LMS)] and two long-term missions (Skylab 1993 and NASA/MIR, 1996-1998). Measurements made include dietary intake (six missions), nitrogen balance (four missions), whole-body protein kinetics with [15N]glycine as the tracer (four missions) and cortisol excretion (three missions). Also available for comparison are bed rest studies with and without exercise. The purpose of this paper is to see what can be learnt about the muscle loss problem by comparing metabolic results across the six missions for which data are available and against bed rest. The analysis suggests that there is a linkage between the inability to maintain energy balance and exercise, and the connection is the decreased efficiency of removal of the metabolic by-products of exercise (heat, CO2) during space flight.

  12. An annual energy and carbon dioxide balance from the CarboEurope wetland site at Tadham Moor, UK

    NASA Astrophysics Data System (ADS)

    Lloyd, C. R.; Harding, R. J.

    2003-04-01

    Peat-rich wetlands can be a major source or sink of carbon depending on the particular hydrological, climatic and biological conditions occurring throughout the year. In managed agricultural wetlands, such a system's equilibrium can be perturbed through farming practice that seeks to maximise crop yield from hay and cattle, and from ecological pressure to maximise the period of inundation. The effects upon the energy and carbon balance brought about by the varying hydrology, climate and farming practice are conplex and require long-term measurements to appreciate the overall gain or loss of the carbon store of vegetation and soil, and to gauge the consequences of current practice upon the wetlands future. Continuous eddy correlation measurements of energy, evaporation and carbon dioxide fluxes were begun in June 1999 at Tadham Moor as part of the EC funded CarboEurope cluster. Tadham Moor is a managed wetland site within the Somerset Levels south of Bristol, UK. A full years data is used to highlight the oscillations and progressions of the energy balance and Net Ecosystem Productivity as climate, hydrology and farming practice alter the overall balance and to create an annual budget of energy and carbon dioxide exchange.

  13. Water, Ice, and Meteorological Measurements at South Cascade Glacier, Washington, Balance Years 2004 and 2005

    USGS Publications Warehouse

    Bidlake, William R.; Josberger, Edward G.; Savoca, Mark E.

    2007-01-01

    Winter snow accumulation and summer snow and ice ablation were measured at South Cascade Glacier, Washington, to estimate glacier mass-balance quantities for balance years 2004 and 2005. The North Cascade Range in the vicinity of South Cascade Glacier accumulated smaller than normal winter snowpacks during water years 2004 and 2005. Correspondingly, the balance years 2004 and 2005 maximum winter snow balances of South Cascade Glacier, 2.08 and 1.97 meters water equivalent, respectively, were smaller than the average of such balances since 1959. The 2004 glacier summer balance (-3.73 meters water equivalent) was the eleventh most negative during 1959 to 2005 and the 2005 glacier summer balance (-4.42 meters water equivalent) was the third most negative. The relatively small winter snow balances and unusually negative summer balances of 2004 and 2005 led to an overall loss of glacier mass. The 2004 and 2005 glacier net balances, -1.65 and -2.45 meters water equivalent, respectively, were the seventh and second most negative during 1953 to 2005. For both balance years, the accumulation area ratio was less than 0.05 and the equilibrium line altitude was higher than the glacier. The unusually negative 2004 and 2005 glacier net balances, combined with a negative balance previously reported for 2003, resulted in a cumulative 3-year net balance of -6.20 meters water equivalent. No equal or greater 3-year mass loss has occurred previously during the more than 4 decades of U.S. Geological Survey mass-balance measurements at South Cascade Glacier. Accompanying the glacier mass losses were retreat of the terminus and reduction of total glacier area. The terminus retreated at a rate of about 17 meters per year during balance year 2004 and 15 meters per year during balance year 2005. Glacier area near the end of balance years 2004 and 2005 was 1.82 and 1.75 square kilometers, respectively. Runoff from the basin containing the glacier and from an adjacent nonglacierized basin was

  14. Diagnosing ocean energy transports from earth radiation budget measurements

    NASA Technical Reports Server (NTRS)

    Sohn, Byung-Ju; Smith, Eric A.

    1992-01-01

    The maximum energy production (MEP) principle suggested by Paltridge (1975) is applied to separate the satellite-inferred required total transports into the atmospheric and the oceanic components within a two-dimensional (2D) framework. For this purpose, the required 2D energy transports (Sohn and Smith, 1991) are imposed on Paltridge's energy balance model which is then solved as a variational problem. The results provide separated atmospheric and oceanic transports on a 2D basis such that the total divergence is equal to the net radiation measured from a satellite.

  15. Energy Balanced Strategies for Maximizing the Lifetime of Sparsely Deployed Underwater Acoustic Sensor Networks

    PubMed Central

    Luo, Hanjiang; Guo, Zhongwen; Wu, Kaishun; Hong, Feng; Feng, Yuan

    2009-01-01

    Underwater acoustic sensor networks (UWA-SNs) are envisioned to perform monitoring tasks over the large portion of the world covered by oceans. Due to economics and the large area of the ocean, UWA-SNs are mainly sparsely deployed networks nowadays. The limited battery resources is a big challenge for the deployment of such long-term sensor networks. Unbalanced battery energy consumption will lead to early energy depletion of nodes, which partitions the whole networks and impairs the integrity of the monitoring datasets or even results in the collapse of the entire networks. On the contrary, balanced energy dissipation of nodes can prolong the lifetime of such networks. In this paper, we focus on the energy balance dissipation problem of two types of sparsely deployed UWA-SNs: underwater moored monitoring systems and sparsely deployed two-dimensional UWA-SNs. We first analyze the reasons of unbalanced energy consumption in such networks, then we propose two energy balanced strategies to maximize the lifetime of networks both in shallow and deep water. Finally, we evaluate our methods by simulations and the results show that the two strategies can achieve balanced energy consumption per node while at the same time prolong the networks lifetime. PMID:22399970

  16. Relationship Between Cognitive Assessment and Balance Measures in Adolescents Referred for Vestibular Physical Therapy After Concussion

    PubMed Central

    Alsalaheen, Bara A.; Whitney, Susan L.; Marchetti, Gregory F.; Furman, Joseph M.; Kontos, Anthony P.; Collins, Michael W.; Sparto, Patrick J.

    2016-01-01

    Objective To examine the relationship between cognitive and balance performance in adolescents with concussion. Design Retrospective case series. Setting Tertiary. Patients Sixty patients. Interventions Correlation analyses were performed to describe the relationship between symptoms, cognitive measure, and balance measure at the time of initiation of vestibular physical therapy. Main Outcome Measures Cognitive performance was assessed using the Immediate Post-concussion Assessment and Cognitive Testing (ImPACT). The dizziness and balance function measures included dizziness severity rating, Activities-specific Balance Confidence scale (ABC), Dizziness Handicap Inventory (DHI), Functional Gait Assessment, gait speed, Timed “UP and GO,” Five Times Sit to Stand, and Sensory Organization Test (SOT). To account for multiple comparisons, the False Discovery Rate method was used. Results Performance measures of balance were significantly correlated with cognitive measures. Greater total symptom scores were related to greater impairment in the ABC and DHI (r = 0.35-0.39, P ≤ 0.008) and worse performance in condition 2 of the SOT (r = −0.48, P = 0.004). Among the ImPACT composite scores, lower memory scores were correlated with impaired balance performance measures (r = 0.37-0.59, P ≤ 0.012). Lower visual memory was also correlated with worse ABC scores. Conclusions The significant relationships reported between the cognitive performance scores and balance measures may reflect that similar levels of functioning exist across domains in individuals with protracted recovery who receive vestibular physical therapy. PMID:25706663

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

    NASA Technical Reports Server (NTRS)

    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. Coordinated regulation of photosynthetic and respiratory components is necessary to maintain chloroplast energy balance in varied growth conditions.

    PubMed

    Dahal, Keshav; Martyn, Greg D; Alber, Nicole A; Vanlerberghe, Greg C

    2016-12-23

    Mitochondria have a non-energy-conserving alternative oxidase (AOX) proposed to support photosynthesis, perhaps by promoting energy balance under varying growth conditions. To investigate this, wild-type (WT) Nicotiana tabacum were compared with AOX knockdown and overexpression lines. In addition, the amount of AOX protein in WT plants was compared with that of chloroplast light-harvesting complex II (LHCB2), whose amount is known to respond to chloroplast energy status. With increased growth irradiance, WT leaves maintained higher rates of respiration in the light (R L), but no differences in R L or photosynthesis were seen between the WT and transgenic lines, suggesting that, under non-stress conditions, AOX was not critical for leaf metabolism, regardless of growth irradiance. However, under drought, the AOX amount became an important determinant of R L, which in turn was an important determinant of chloroplast energy balance (measured as photosystem II excitation pressure, EP), and photosynthetic performance. In the WT, the AOX amount increased and the LHCB2 amount decreased with increased growth irradiance or drought severity. These changes in protein amounts correlated strongly, in opposing ways, with growth EP. This suggests that a signal deriving from the photosynthetic electron transport chain status coordinately controls the amounts of AOX and LHCB2, which then both contribute to maintaining chloroplast energy balance, particularly under stress conditions.

  19. The urban energy balance of a lightweight low-rise neighborhood in Andacollo, Chile

    NASA Astrophysics Data System (ADS)

    Crawford, Ben; Krayenhoff, E. Scott; Cordy, Paul

    2016-10-01

    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 various

  20. Diet/Energy Balance Affect Sleep and Wakefulness Independent of Body Weight

    PubMed Central

    Perron, Isaac J.; Pack, Allan I.; Veasey, Sigrid

    2015-01-01

    Study Objectives: Excessive daytime sleepiness commonly affects obese people, even in those without sleep apnea, yet its causes remain uncertain. We sought to determine whether acute dietary changes could induce or rescue wake impairments independent of body weight. Design: We implemented a novel feeding paradigm that generates two groups of mice with equal body weight but opposing energetic balance. Two subsets of mice consuming either regular chow (RC) or high-fat diet (HFD) for 8 w were switched to the opposite diet for 1 w. Sleep recordings were conducted at Week 0 (baseline), Week 8 (pre-diet switch), and Week 9 (post-diet switch) for all groups. Sleep homeostasis was measured at Week 8 and Week 9. Participants: Young adult, male C57BL/6J mice. Measurements and Results: Differences in total wake, nonrapid eye movement (NREM), and rapid eye movement (REM) time were quantified, in addition to changes in bout fragmentation/consolidation. At Week 9, the two diet switch groups had similar body weight. However, animals switched to HFD (and thus gaining weight) had decreased wake time, increased NREM sleep time, and worsened sleep/wake fragmentation compared to mice switched to RC (which were in weight loss). These effects were driven by significant sleep/wake changes induced by acute dietary manipulations (Week 8 → Week 9). Sleep homeostasis, as measured by delta power increase following sleep deprivation, was unaffected by our feeding paradigm. Conclusions: Acute dietary manipulations are sufficient to alter sleep and wakefulness independent of body weight and without effects on sleep homeostasis. Citation: Perron IJ, Pack AI, Veasey S. Diet/energy balance affect sleep and wakefulness independent of body weight. SLEEP 2015;38(12):1893–1903. PMID:26158893

  1. Berberine interfered with breast cancer cells metabolism, balancing energy homeostasis.

    PubMed

    Tan, Wen; Li, Ning; Tan, Rui; Zhong, Zhangfeng; Suo, Zhanwei; Yang, Xian; Wang, Yitao; Hu, Xiaodong

    2015-01-01

    Berberine exerted anti-cancer effect in various cancer cell lines, and was also implied in the treatment of metabolic related diseases. Given the metabolic modulation, we hypothesized that berberine possessed anti-cancer effect under the assistance of metabolic interference. Working as a modulator, metabolic enzyme inhibitor or complex network regulator in energy metabolism, berberine was highlighted in current cancer research. A reasonable cross talk between Chinese medicine and energy homeostasis provided a solid foundation for berberine interference on cancer cells reprogramming metabolism. Our result showed that berberine regulated the reprogramming metabolism through three aspects simultaneously, including mitochondrial oxidative phosphorylation, glycolysis and macromolecular synthesis. This interference with reprogramming metabolism was a continuous, simultaneous and sustainable approach in a moderate mode. And it could be regarded as a gentle and virtuous cycle from a multi-level perspective, indicating an integrated approach in cancer therapy. Meanwhile, we thought that Chinese medicine could link cancer and metabolic related diseases from a dynamic perspective through integrated network pharmacology. This cross talk would be a realistic and significant strategy for anti-cancer drug discovery and needs further investigation in future.

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

    PubMed

    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 (<1 m) canopies. The key element of the mobile device is a handheld four-component net radiometer for the quantification of net radiation, albedo and infrared surface temperature, which is complemented with measurements of air temperature, 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.

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

    NASA Astrophysics Data System (ADS)

    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 (<1 m) canopies. The key element of the mobile device is a handheld four-component net radiometer for the quantification of net radiation, albedo and infrared surface temperature, which is complemented with measurements of air temperature, 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.

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

    NASA Astrophysics Data System (ADS)

    Tasser, Erich; Wohlfahrt, Georg

    2014-05-01

    We present a mobile device for the quantification of the small-scale spatial variability in the surface energy balance components and several auxiliary variables of short-statured canopies. The key element of the mobile device is a hand-held four-component net radiometer for the quantification of net radiation, albedo and infrared surface temperature, which is complemented with measurements of air temperature, 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 (i) land use and (ii) slope and aspect of the underlying surface, (iii) controls on landscape-scale variability in soil temperature and albedo, and (iv) the estimation of evapotranspiration based exclusively on measurements with the mobile device.

  5. Instrumented measurement of balance and postural control in individuals with lower limb amputation: a critical review.

    PubMed

    Jayakaran, Prasath; Johnson, Gillian M; Sullivan, S John; Nitz, Jennifer C

    2012-09-01

    Measurement of balance and postural performance that underpins activities of daily living is important in the rehabilitation of individuals with a lower limb amputation (LLA), and there are a number of methods and strategies available for this purpose. To provide an evidence-based choice of approach, this review aims to critically review the tasks and outcome measures utilized in studies investigating static and dynamic balance using instrumented measurement devices in individuals with a LLA. A systematic search was conducted on multiple databases using keyword or subject headings appropriate to the respective database. Articles investigating static or dynamic balance in adults with LLA by means of instrumented measures were considered for the review. A total of 21 articles were included in the review. The static balance ability of individuals with an LLA has been investigated thoroughly, but their dynamic balance attributes remain relatively unexplored. Although the individual studies do provide valuable information on balance ability in the LLA, the heterogeneity in study designs and measures did not allow an overall analysis of the tasks and the outcome measures used. On the basis of these findings, this review provides an insight into the measurement of balance in amputees to inform novice researchers and clinicians working with individuals with an LLA.

  6. A Hessian-Based Method for Uncertainty Quantification of Parameters of Terrestrial Water and Energy Balance Equations

    NASA Astrophysics Data System (ADS)

    Farhadi, L.

    2015-12-01

    All land parameterizations used in hydrologic, ecological and climate models or assimilation systems contain key closure functions that relate water and energy balances. Key among these closure functions is reduction of evapotranspiration (latent heat flux) due to deficit in soil water availability (EF, the fraction of available energy released as latent heat), This closure is a flux-based diagnostic that can be calculated for any model. Its estimation as a function of soil moisture state (S) can be used to diagnose compatibility and fidelity of parameterizations. Important as this closure is, it remains empirical and mostly untested especially across diverse landscapes and climates. In this study we develop and apply mapping estimation capability for key unknown parameters that link the terrestrial water and energy balance equations. A single cost function is posed that measures moisture and temperature dependent errors solely in terms of observed forcings, surface states and unknown parameters. This cost function is minimized with respect to parameters to estimate key parameters of water and energy balance equation. The uncertainty of the estimated parameters (and associated statistical confidence limits) is obtained through the inverse of Hessian of the cost function, which is an approximation of the covariance matrix. The hessian of the cost function will be used to guide the formulation of a well-posed estimation problem. This calibration free method is verified at point scale and at regional scale using remote sensing measurements. The focus is to find the functional form of the evaporative fraction dependence on soil moisture, the key closure function for surface and subsurface heat and moisture dynamics, using remote sensing data. Accurate estimation of key parameters and closure function of water and energy balance equation can be used to guide the refinement of Land Surface Models and enhance weather and climate forecast skill.

  7. Uncertainty analysis of the Operational Simplified Surface Energy Balance (SSEBop) model at multiple flux tower sites

    NASA Astrophysics Data System (ADS)

    Chen, Mingshi; Senay, Gabriel B.; Singh, Ramesh K.; Verdin, James P.

    2016-05-01

    Evapotranspiration (ET) is an important component of the water cycle - ET from the land surface returns approximately 60% of the global precipitation back to the atmosphere. ET also plays an important role in energy transport among the biosphere, atmosphere, and hydrosphere. Current regional to global and daily to annual ET estimation relies mainly on surface energy balance (SEB) ET models or statistical and empirical methods driven by remote sensing data and various climatological databases. These models have uncertainties due to inevitable input errors, poorly defined parameters, and inadequate model structures. The eddy covariance measurements on water, energy, and carbon fluxes at the AmeriFlux tower sites provide an opportunity to assess the ET modeling uncertainties. In this study, we focused on uncertainty analysis of the Operational Simplified Surface Energy Balance (SSEBop) model for ET estimation at multiple AmeriFlux tower sites with diverse land cover characteristics and climatic conditions. The 8-day composite 1-km MODerate resolution Imaging Spectroradiometer (MODIS) land surface temperature (LST) was used as input land surface temperature for the SSEBop algorithms. The other input data were taken from the AmeriFlux database. Results of statistical analysis indicated that the SSEBop model performed well in estimating ET with an R2 of 0.86 between estimated ET and eddy covariance measurements at 42 AmeriFlux tower sites during 2001-2007. It was encouraging to see that the best performance was observed for croplands, where R2 was 0.92 with a root mean square error of 13 mm/month. The uncertainties or random errors from input variables and parameters of the SSEBop model led to monthly ET estimates with relative errors less than 20% across multiple flux tower sites distributed across different biomes. This uncertainty of the SSEBop model lies within the error range of other SEB models, suggesting systematic error or bias of the SSEBop model is within the

  8. Uncertainty analysis of the Operational Simplified Surface Energy Balance (SSEBop) model at multiple flux tower sites

    USGS Publications Warehouse

    Chen, Mingshi; Senay, Gabriel B.; Singh, Ramesh K.; Verdin, James P.

    2016-01-01

    Evapotranspiration (ET) is an important component of the water cycle – ET from the land surface returns approximately 60% of the global precipitation back to the atmosphere. ET also plays an important role in energy transport among the biosphere, atmosphere, and hydrosphere. Current regional to global and daily to annual ET estimation relies mainly on surface energy balance (SEB) ET models or statistical and empirical methods driven by remote sensing data and various climatological databases. These models have uncertainties due to inevitable input errors, poorly defined parameters, and inadequate model structures. The eddy covariance measurements on water, energy, and carbon fluxes at the AmeriFlux tower sites provide an opportunity to assess the ET modeling uncertainties. In this study, we focused on uncertainty analysis of the Operational Simplified Surface Energy Balance (SSEBop) model for ET estimation at multiple AmeriFlux tower sites with diverse land cover characteristics and climatic conditions. The 8-day composite 1-km MODerate resolution Imaging Spectroradiometer (MODIS) land surface temperature (LST) was used as input land surface temperature for the SSEBop algorithms. The other input data were taken from the AmeriFlux database. Results of statistical analysis indicated that the SSEBop model performed well in estimating ET with an R2 of 0.86 between estimated ET and eddy covariance measurements at 42 AmeriFlux tower sites during 2001–2007. It was encouraging to see that the best performance was observed for croplands, where R2 was 0.92 with a root mean square error of 13 mm/month. The uncertainties or random errors from input variables and parameters of the SSEBop model led to monthly ET estimates with relative errors less than 20% across multiple flux tower sites distributed across different biomes. This uncertainty of the SSEBop model lies within the error range of other SEB models, suggesting systematic error or bias of the SSEBop model is within

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

    PubMed Central

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

    2011-01-01

    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 programs aimed at either amplifying endogenous anorexigenic/lipolytic signaling or blocking endogenous orexigenic/lipogenic signaling. Here, we discuss the efficacy and safety of targeting these pathways for the pharmacologic treatment of obesity. PMID:21297878

  10. Measuring Air-water Interfacial Area for Soils Using the Mass Balance Surfactant-tracer Method

    PubMed Central

    Araujo, Juliana B.; Mainhagu, Jon; Brusseau, Mark L.

    2015-01-01

    There are several methods for conducting interfacial partitioning tracer tests to measure air-water interfacial area in porous media. One such approach is the mass balance surfactant tracer method. An advantage of the mass-balance method compared to other tracer-based methods is that a single test can produce multiple interfacial area measurements over a wide range of water saturations. The mass-balance method has been used to date only for glass beads or treated quartz sand. The purpose of this research is to investigate the effectiveness and implementability of the mass-balance method for application to more complex porous media. The results indicate that interfacial areas measured with the mass-balance method are consistent with values obtained with the miscible-displacement method. This includes results for a soil, for which solid-phase adsorption was a significant component of total tracer retention. PMID:25950136

  11. Effect of mosaic representation of vegetation in land surface schemes on simulated energy and carbon balances

    NASA Astrophysics Data System (ADS)

    Li, R.; Arora, V. K.

    2011-06-01

    Energy and carbon balance implications of representing vegetation using a composite or mosaic approach in a land surface scheme are investigated. In the composite approach the attributes of different plant functional types (PFTs) present in a grid cell are aggregated in some fashion for energy and water balance calculations. The resulting physical environmental conditions (including net radiation, soil moisture and soil temperature) are common to all PFTs and affect their ecosystem processes. In the mosaic approach energy and water balance calculations are performed separately for each PFT tile using its own vegetation attributes, so each PFT "sees" different physical environmental conditions and its carbon balance evolves somewhat differently from that in the composite approach. Simulations are performed at selected boreal, temperate and tropical locations to illustrate the differences caused by using the composite versus the mosaic approaches of representing vegetation. Differences in grid averaged primary energy fluxes are generally less than 5 % between the two approaches. Grid-averaged carbon fluxes and pool sizes can, however, differ by as much as 46 %. Simulation results suggest that differences in carbon balance between the two approaches arise primarily through differences in net radiation which directly affects net primary productivity, and thus leaf area index and vegetation biomass.

  12. Effect of mosaic representation of vegetation in land surface schemes on simulated energy and carbon balances

    NASA Astrophysics Data System (ADS)

    Li, R.; Arora, V. K.

    2012-01-01

    Energy and carbon balance implications of representing vegetation using a composite or mosaic approach in a land surface scheme are investigated. In the composite approach the attributes of different plant functional types (PFTs) present in a grid cell are aggregated in some fashion for energy and water balance calculations. The resulting physical environmental conditions (including net radiation, soil moisture and soil temperature) are common to all PFTs and affect their ecosystem processes. In the mosaic approach energy and water balance calculations are performed separately for each PFT tile using its own vegetation attributes, so each PFT "sees" different physical environmental conditions and its carbon balance evolves somewhat differently from that in the composite approach. Simulations are performed at selected boreal, temperate and tropical locations to illustrate the differences caused by using the composite versus mosaic approaches of representing vegetation. These idealized simulations use 50% fractional coverage for each of the two dominant PFTs in a grid cell. Differences in simulated grid averaged primary energy fluxes at selected sites are generally less than 5% between the two approaches. Simulated grid-averaged carbon fluxes and pool sizes at these sites can, however, differ by as much as 46%. Simulation results suggest that differences in carbon balance between the two approaches arise primarily through differences in net radiation which directly affects net primary productivity, and thus leaf area index and vegetation biomass.

  13. Importance of Soil Moisture and Vegetation Cover for Energy Balance partition in Burkina Faso

    NASA Astrophysics Data System (ADS)

    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.

  14. Hurricane disturbance and recovery of carbon and energy balance in a tidal mangrove forest

    NASA Astrophysics Data System (ADS)

    Barr, J. G.; Engel, V.; Fuentes, J. D.; Smith, T.

    2009-12-01

    The goal of this presentation is to determine mangrove ecosystem function following a disturbance. Hurricane Wilma made landfall as a Category 3 storm along the western coast of the Florida Everglades in October 2005. The storm deposited large amounts of marine calcitic sediments. At a site 2 km inland from the center of landfall, 5 cm of sediments were deposited, and 30% of mature trees were defoliated and killed. At this site, tower based measurements of carbon dioxide eddy covariance and energy balance were started in 2004. Several years of repeated measurements of tree basal area, litterfall, root turnover, and peat surface elevations also pre-date the storm. Measurements resumed in 2006, providing an opportunity to examine the effects of hurricane disturbance on coastal ecosystem functioning. Following defoliation sensible heating decreased and latent heating increased. Reductions in sensible heating are attributed to decreased energy exchange at the forest crown and increased solar energy reaching the peat surface. Increases in latent heating are attributed to increased turbulent transport of latent heat fluxes from the saturated soil and water beneath the forest. Soil temperature and soil heat fluxes increased after the storm. Reductions in net ecosystem carbon assimilation rates (NEE) are apparent 4 years after the storm, though the rates are now approaching pre-storm values. The increased soil temperature following the storm presumably led to increased soil respiration which, along with the tree mortality, branch loss, and defoliation, explained the decreases in ecosystem-level carbon assimilation rates following the storm. Minimum half-hourly NEE values reached -25 μmol m-2 s-1 and -22 μmol m-2 s-1 before and after the storm, respectively. Daytime ecosystem respiration rates (Re) estimated using the intercept of light-response curves increased by an average of 1.2 μmol m-2 s-1 at a reference temperature of 20 oC during low tide periods. Nightime Re at

  15. Towards a more detailed representation of the energy balance in a coupled land surface model

    NASA Astrophysics Data System (ADS)

    Ryder, J.; Polcher, J.; Luyssaert, S.

    2012-04-01

    Currently, the land-surface region sequesters 25% of global CO2 emissions. In addition to climate change, increasing atmospheric CO2 concentrations, fertilisation and nitrogen deposition, this sink is thought to be largely due to land management. When applied deliberately to enhance the terrestrial carbon sink strength, this land management may have unintended effects on the energy budget, potentially offsetting the radiative effect of carbon sequestration. As with other land surface models, the present release of ORCHIDEE (the land surface model of the IPSL Earth system model) has difficulties in reproducing consistently observed energy balances (Pitman et al., 2009; Jimenez et al., 2011; de Noblet-Ducoudré et al., 2011). Hence, the model must be improved to be better able to study the radiative effect of forest management and land use change. This observation serves as a starting point in this research - improving the level of detail in energy balance simulations of the surface layer. We here outline the structure of a new detailed and practical simulation of the energy budget that is currently under development within the surface model ORCHIDEE, and will be coupled to the atmospheric model LMDZ. The most detailed simulations of the surface layer energy budget are detailed iterative multi-layer canopy models, such as Ogeé et al. (2003), which are linked to specific measurement sites and do not interact with the atmosphere. In this current project, we aim to create a model that will implement the insights obtained in those previous studies and improve upon the present ORCHIDEE parameterisation, but will run stably and efficiently when coupled to an atmospheric model. This work involves a replacement of the existing allocation of 14 different types of vegetation within each surface tile (the 'Plant Functional Types') by a more granular scheme that can be modified to reflect changes in attributes such as vegetation density, leaf type, distribution (clumping

  16. Resistant starch and energy balance: impact on weight loss and maintenance.

    PubMed

    Higgins, Janine A

    2014-01-01

    The obesity epidemic has prompted researchers to find effective weight-loss and maintenance tools. Weight loss and subsequent maintenance are reliant on energy balance--the net difference between energy intake and energy expenditure. Negative energy balance, lower intake than expenditure, results in weight loss whereas positive energy balance, greater intake than expenditure, results in weight gain. Resistant starch has many attributes, which could promote weight loss and/or maintenance including reduced postprandial insulinemia, increased release of gut satiety peptides, increased fat oxidation, lower fat storage in adipocytes, and preservation of lean body mass. Retention of lean body mass during weight loss or maintenance would prevent the decrease in basal metabolic rate and, therefore, the decrease in total energy expenditure, that occurs with weight loss. In addition, the fiber-like properties of resistant starch may increase the thermic effect of food, thereby increasing total energy expenditure. Due to its ability to increase fat oxidation and reduce fat storage in adipocytes, resistant starch has recently been promoted in the popular press as a "weight loss wonder food". This review focuses on data describing the effects of resistant starch on body weight, energy intake, energy expenditure, and body composition to determine if there is sufficient evidence to warrant these claims.

  17. The effect of breakfast on appetite regulation, energy balance and exercise performance.

    PubMed

    Clayton, David J; James, Lewis J

    2016-08-01

    The belief that breakfast is the most important meal of day has been derived from cross-sectional studies that have associated breakfast consumption with a lower BMI. This suggests that breakfast omission either leads to an increase in energy intake or a reduction in energy expenditure over the remainder of the day, resulting in a state of positive energy balance. However, observational studies do not imply causality. A number of intervention studies have been conducted, enabling more precise determination of breakfast manipulation on indices of energy balance. This review will examine the results from these studies in adults, attempting to identify causal links between breakfast and energy balance, as well as determining whether consumption of breakfast influences exercise performance. Despite the associations in the literature, intervention studies have generally found a reduction in total daily energy intake when breakfast is omitted from the daily meal pattern. Moreover, whilst consumption of breakfast supresses appetite during the morning, this effect appears to be transient as the first meal consumed after breakfast seems to offset appetite to a similar extent, independent of breakfast. Whether breakfast affects energy expenditure is less clear. Whilst breakfast does not seem to affect basal metabolism, breakfast omission may reduce free-living physical activity and endurance exercise performance throughout the day. In conclusion, the available research suggests breakfast omission may influence energy expenditure more strongly than energy intake. Longer term intervention studies are required to confirm this relationship, and determine the impact of these variables on weight management.

  18. National Assessment of Energy Storage for Grid Balancing and Arbitrage: Phase 1, WECC

    SciTech Connect

    Kintner-Meyer, Michael CW; Balducci, Patrick J.; Colella, Whitney G.; Elizondo, Marcelo A.; Jin, Chunlian; Nguyen, Tony B.; Viswanathan, Vilayanur V.; Zhang, Yu

    2012-06-01

    To examine the role that energy storage could play in mitigating the impacts of the stochastic variability of wind generation on regional grid operation, the Pacific Northwest National Laboratory (PNNL) examined a hypothetical 2020 grid scenario in which additional wind generation capacity is built to meet renewable portfolio standard targets in the Western Interconnection. PNNL developed a stochastic model for estimating the balancing requirements using historical wind statistics and forecasting error, a detailed engineering model to analyze the dispatch of energy storage and fast-ramping generation devices for estimating size requirements of energy storage and generation systems for meeting new balancing requirements, and financial models for estimating the life-cycle cost of storage and generation systems in addressing the future balancing requirements for sub-regions in the Western Interconnection. Evaluated technologies include combustion turbines, sodium sulfur (Na-S) batteries, lithium ion batteries, pumped-hydro energy storage, compressed air energy storage, flywheels, redox flow batteries, and demand response. Distinct power and energy capacity requirements were estimated for each technology option, and battery size was optimized to minimize costs. Modeling results indicate that in a future power grid with high-penetration of renewables, the most cost competitive technologies for meeting balancing requirements include Na-S batteries and flywheels.

  19. Energy balance and canopy conductance of a boreal aspen forest: Partitioning overstory and understory components

    NASA Astrophysics Data System (ADS)

    Blanken, P. D.; Black, T. A.; Yang, P. C.; Neumann, H. H.; Nesic, Z.; Staebler, R.; den Hartog, G.; Novak, M. D.; Lee, X.

    1997-12-01

    The energy balance components were measured throughout most of 1994 in and above a southern boreal aspen (Populus tremuloides Michx.) forest (53.629°N 106.200°W) with a hazelnut (Corylus cornuta Marsh.) understory as part of the Boreal Ecosystem-Atmosphere Study. The turbulent fluxes were measured at both levels using the eddy-covariance technique. After rejection of suspect data due to instationarity or inhomogeneity, occasional erratic behavior in turbulent fluxes and lack of energy balance closure led to a recalculation of the fluxes of sensible and latent heat using their ratio and the available energy. The seasonal development in leaf area was reflected in a strong seasonal pattern of the energy balance. Leaf growth began during the third week of May with a maximum forest leaf area index of 5.6 m2 m-2 reached by mid-July. During the full-leaf period, aspen and hazelnut accounted for approximately 40 and 60% of the forest leaf area, respectively. Sensible heat was the dominant consumer of forest net radiation during the preleaf period, while latent heat accounted for the majority of forest net radiation during the leafed period. Hazelnut transpiration accounted for 25% of the forest transpiration during the summer months. During the full-leaf period (June 1 to September 7) daytime dry-canopy mean aspen and hazelnut canopy conductances were 330 mmol m-2 s-1 (8.4 mm s-1) (70% of the total forest conductance) and 113 mmol m-2 s-1 (2.9 mm s-1) (24% of the total forest conductance), respectively. Maximum aspen and hazelnut canopy conductances were 1200 mmol m-2 s-1 (30 mm s-1) and 910 mmol m-2 s-1 (23 mm s-1 ), respectively, and maximum stomatal conductances were 490 mmol m-2 s-1 (12.5 mm s-1) and 280 mmol m-2 s-1 (7 m s-1), aspen and hazelnut, respectively. Both species showed a decrease in canopy conductance as the saturation deficit increased and both showed an increase in canopy conductance as the photosynthetic active radiation increased. There was a linear

  20. Energy Balance and Hydrological Modelling of Zongo Glacier, Bolivia, Using ERA-40 Reanalysis Data

    NASA Astrophysics Data System (ADS)

    Duguay, M.; Hock, R.; Sicart, J.; Coudrain, A.

    2008-12-01

    In the Andes several regions profit significantly from glacial melt water for drink water supply and electricity production. During the dry season, glacier melt is significant source of water in the semi-arid region of La Paz, Bolivia. The Andean glaciers are retreating and water resources after reaching a culmination, will decrease. This implicates serious environmental and socio-economical consequences. For an effective attenuation, it is crucial to furnish quantitative predictions of the glacier mass loss and its effects on the water resources in these regions. A distributed energy balance model has been developed to model mass balance and melt induced discharge of tropical glaciers. We want to predict the changes in glacier melt discharge in response to future climate change for the region of La Paz, Bolivia and later regionalize the model to a larger area. The model operates on daily steps, has a 20 m grid resolution, and is forced by daily data of air temperature, humidity, wind speed, global radiation and precipitation. As a test basin, we calibrate the model at Glaciar Zongo, Bolivia, 16°15'S , 68°°10'W which is monitored by the French Institute for Research for the Development (IRD) . Zongo Glacier is a 1,8 km2 large and the catchment is 63% glacierized. Mass balance, weather station and discharge data are available on daily basis from 1991 onward. The measurements have gaps and only two years (1994-95 and 1999-00) with continuous data are available. In order to allow for multi-year simulations we force the model by daily ERA-40 reanalysis data from the European Center for Weather Forecast (ECMWF). To downscale the data we compare the daily data 1991-2002 to the observations at the glacier. Results indicate a fair agreement for air temperature, but a rather poor correlation between the ERA-40 data and the observations for wind speed, global radiation and precipitation. The correlation is improved using monthly values. So far, test runs of the model

  1. Understanding gas-surface interactions from direct force measurements using a specialized torsion balance

    SciTech Connect

    Cook, S.R.; Hoffbauer, M.A.

    1996-12-31

    The first comprehensive measurements of the magnitude and direction of the forces exerted on surfaces by molecular beams are discussed and used to obtain information about the microscopic properties of the gas-surface interactions. This unique approach is not based on microscopic measurements of the scattered molecules. The reduced force coefficients are introduced as a new set of parameters that completely describe the macroscopic average momentum transfer to a surface by an incident molecular beam. By using a specialized torsion balance and molecular beams of N{sub 2}, CO, CO{sub 2}, and H{sub 2}, the reduced force coefficients are determined from direct measurements of the force components exerted on surface of a solar panel array material, Kapton, SiO{sub 2}-coated Kapton, and Z-93 as a function of the angle of incidence ranging from 0{degrees} to 85{degrees}. The absolute flux densities of the molecular beams were measured using a different torsion balance with a beam-stop that nullified the force of the scattered molecules. Standard time-of-flight techniques were used to determine the flux-weighted average velocities of the various molecular beams ranging from 1600 m/s to 4600 m/s. The reduced force coefficients can be used to directly obtain macroscopic average properties of the scattered molecules, such as the flux-weighted average velocity and translational energy, that can then be used to determine microscopic details concerning gas-surface interactions without the complications associated with averaging microscopic measurements.

  2. Developmental programming of energy balance regulation: is physical activity more 'programmable' than food intake?

    PubMed

    Zhu, Shaoyu; Eclarinal, Jesse; Baker, Maria S; Li, Ge; Waterland, Robert A

    2016-02-01

    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 mechanisms underlying such developmental programming of energy balance are poorly understood, limiting our ability to intervene. Most studies of developmental programming of energy balance have focused on persistent alterations in the regulation of energy intake; energy expenditure has been relatively underemphasised. In particular, very few studies have evaluated developmental programming of physical activity. The aim of this review is to summarise recent evidence that early environment may have a profound impact on establishment of individual propensity for physical activity. Recently, we characterised two different mouse models of developmental programming of obesity; one models fetal growth restriction followed by catch-up growth, and the other models early postnatal overnutrition. In both studies, we observed alterations in body-weight regulation that persisted to adulthood, but no group differences in food intake. Rather, in both cases, programming of energy balance appeared to be due to persistent alterations in energy expenditure and spontaneous physical activity (SPA). These effects were stronger in female offspring. We are currently exploring the hypothesis that developmental programming of SPA occurs via induced sex-specific alterations in epigenetic regulation in the hypothalamus and other regions of the central nervous system. We will summarise the current progress towards testing this hypothesis. Early environmental influences on establishment of physical activity are likely an important factor in developmental programming of energy balance. Understanding the fundamental underlying mechanisms in appropriate animal models will help determine whether early life

  3. Verification Of Energy Balance In The Ansys V5.4 Thermal Calculations

    SciTech Connect

    H. Marr; M.J. Anderson

    2001-02-08

    The objective of this calculation is to verify the energy balance of the thermal calculations analyzed by ANSYS Version (V) 5.4 solver (see Section 4). The scope of this calculation is limited to calculating the energy balance of a two-dimensional repository thermal representation using the temperatures obtained from ANSYS V5.4. The procedure, AP-3.124, Calculations (Ref. 3), and the Technical Work Plan for: Waste Package Design Description for LA (Ref. 2) are used to develop this calculation. The associated activity is the development of engineering evaluations to support the Licensing Application design activities.

  4. Minimizing Wind Power Producer's Balancing Costs Using Electrochemical Energy Storage: Preprint

    SciTech Connect

    Miettinen, J.; Tikka, V.; Lassila, J.; Partanen, J.; Hodge, B. M.

    2014-08-01

    This paper examines how electrochemical energy storage can be used to decrease the balancing costs of a wind power producer in the Nordic market. Because electrochemical energy storage is developing in both technological and financial terms, a sensitivity analysis was carried out for the most important variables in the wind-storage hybrid system. The system was studied from a wind power producer's point of view. The main result is that there are no technical limitations to using storage for reducing the balancing costs. However, in terms of economic feasibility, installing hybrid wind-storage systems such as the one studied in this paper faces challenges in both the short and long terms.

  5. Mineral balance in milk heated using microwave energy.

    PubMed

    de la Fuente, Miguel Angel; Olano, Agustín; Juárez, Manuela

    2002-04-10

    Milk heated to 75 and 85 degrees C in a water bath or in a microwave oven was assayed for changes in salt partitioning after cooling to room temperature. To properly to assess differences and draw valid comparisons, the two heating methods used in the experiment were applied to samples for identical exposure times, and the samples were heated to attain the same final temperatures. Although the soluble Ca and P(i) contents were lower in the heated milk samples, no significant differences in salt partitioning were found between microwave and conventional heating. Ionic calcium levels in the milk samples pasteurized using microwave energy were very close to the levels in the samples heated in a conventional water bath (approximately 90% of the level in the untreated milk samples). The microwave heating-induced changes were completely reversed after storage at 20 degrees C for 24 h. The coagulation properties of the heated milk samples were also examined, and the coagulation time was longer and the curd formation rate slower in the microwave-heated milk than in the raw milk. Still, the experimental results demonstrated that microwave heating was no more detrimental to the milk than conventional heating and could thus be used for pasteurization purposes.

  6. Daily magnesium fluxes regulate cellular timekeeping and energy balance.

    PubMed

    Feeney, Kevin A; Hansen, Louise L; Putker, Marrit; Olivares-Yañez, Consuelo; Day, Jason; Eades, Lorna J; Larrondo, Luis F; Hoyle, Nathaniel P; O'Neill, John S; van Ooijen, Gerben

    2016-04-21

    Circadian clocks are fundamental to the biology of most eukaryotes, coordinating behaviour and physiology to resonate with the environmental cycle of day and night through complex networks of clock-controlled genes. A fundamental knowledge gap exists, however, between circadian gene expression cycles and the biochemical mechanisms that ultimately facilitate circadian regulation of cell biology. Here we report circadian rhythms in the intracellular concentration of magnesium ions, [Mg(2+)]i, which act as a cell-autonomous timekeeping component to determine key clock properties both in a human cell line and in a unicellular alga that diverged from each other more than 1 billion years ago. Given the essential role of Mg(2+) as a cofactor for ATP, a functional consequence of [Mg(2+)]i oscillations is dynamic regulation of cellular energy expenditure over the daily cycle. Mechanistically, we find that these rhythms provide bilateral feedback linking rhythmic metabolism to clock-controlled gene expression. The global regulation of nucleotide triphosphate turnover by intracellular Mg(2+) availability has potential to impact upon many of the cell's more than 600 MgATP-dependent enzymes and every cellular system where MgNTP hydrolysis becomes rate limiting. Indeed, we find that circadian control of translation by mTOR is regulated through [Mg(2+)]i oscillations. It will now be important to identify which additional biological processes are subject to this form of regulation in tissues of multicellular organisms such as plants and humans, in the context of health and disease.

  7. A new approach to estimating evaporation from lakes and reservoirs based on energy balance and remote sensing data

    NASA Astrophysics Data System (ADS)

    Majidi, Maysam; Sadeghi, Morteza; Shafiei, Mojtaba; Alizadeh, Amin; Farid, Alireza; Azad, Mohammadreza; Vazifedoust, Majid

    2016-04-01

    Estimating evaporation from water bodies such as lakes and reservoirs is commonly a difficult task, especially due to the lack of reliable and available ground data. Remote sensing (RS) data has shown a great potential for filling the gap. Nonetheless, interpretation of the RS data (e.g. optical reflectance, thermal emission, etc.) for estimating water evaporation has remained as a challenge. In this paper, we present a novel approach for estimating water evaporation based on satellite RS data and some readily measurable ground data. In the proposed approach, named as "Reference and Water surface Energy Balance (RWEB)", we define a reference surface and then solve the energy balance equation simultaneously for the reference surfaces and water surface. This approach was tested over the Doosti dam reservoir (north east of Iran) using whether station and RS data as well as water temperature measured biweekly along the study. Accuracy of the RWEB algorithm was examined by comparison to the standard "Bowen Ratio Energy Balance (BREB)" RS algorithm. The RMSD value of 0.047 mm/year indicated a good agreement between RWEB and BREB algorithms, while RWEB provides an easier-to-use approach regarding its required input variables.

  8. Daily magnesium fluxes regulate cellular timekeeping and energy balance

    PubMed Central

    Feeney, Kevin A.; Hansen, Louise L.; Putker, Marrit; Olivares-Yañez, Consuelo; Day, Jason; Eades, Lorna J.; Larrondo, Luis F.; Hoyle, Nathaniel P.; O'Neill, John S.; van Ooijen, Gerben

    2016-01-01

    Circadian clocks are fundamental to the biology of most eukaryotes, coordinating behavior and physiology to resonate with the environmental cycle of day and night through complex networks of clock-controlled genes1–3. A fundamental knowledge gap exists however, between circadian gene expression cycles and the biochemical mechanisms that ultimately facilitate circadian regulation of cell biology4,5. Here we report circadian rhythms in the intracellular concentration of magnesium ions, [Mg2+]i, which act as a cell-autonomous timekeeping component to determine key clock properties in both a human cell line and a unicellular alga that diverged from metazoans more than 1 billion years ago6. Given the essential role of Mg2+ as a cofactor for ATP, a functional consequence of [Mg2+]i oscillations is dynamic regulation of cellular energy expenditure over the daily cycle. Mechanistically, we find that these rhythms provide bilateral feedback linking rhythmic metabolism to clock-controlled gene expression. The global regulation of nucleotide triphosphate turnover by intracellular Mg2+ availability has potential to impact upon many of the cell’s >600 MgATP-dependent enzymes7 and every cellular system where MgNTP hydrolysis becomes rate limiting. Indeed, we find that circadian control of translation by mTOR8 is regulated through [Mg2+]i oscillations. It will now be important to identify which additional biological processes are subject to this form of regulation in tissues of multicellular organisms such as plants and humans, in the context of health and disease. PMID:27074515

  9. Comparison of energy expenditure during the Y-balance test in older adults with different visual acuities

    PubMed Central

    Shin, Sun-Shil; An, Duk-Hyun

    2015-01-01

    [Purpose] This study compared the energy expenditure during the Y-balance test (YBT) between elderly women with good binocular visual acuity (BVA) and those with poor BVA. [Subjects] Twenty-one elderly women who could walk independently were recruited from a community dwelling. Eleven participants had a BVA equal to or less than 0.4 logarithm of the minimum angle of resolution (logMAR), and the other 10 participants had a BVA equal to or better than 0.3 logMAR. [Methods] The participants had an accelerometer attached over the L3 spinous process for measurement of energy expenditure and performed the YBT in the anterior, posteromedial, and posterolateral directions. [Results] The normalized reach distance in the good BVA group during the YBT in three directions and composite reach distance were significantly longer compared with the values in the poor BVA group. The energy expenditure in the good BVA group during the YBT in the three directions was significantly reduced compared with the values in the poor BVA group. [Conclusion] We suggest that visual acuity in the elderly influences dynamic balance and energy expenditure. Elderly subjects with poor BVA showed poor dynamic balance control and an inefficient biomechanical cost strategy compared to subjects with good BVA. PMID:25931711

  10. Pseudomonoenergetic x-ray diffraction measurements using balanced filters for coherent-scatter computed tomography

    SciTech Connect

    Beath, S. R.; Cunningham, I. A.

    2009-05-15

    Coherent-scatter computed tomography (CSCT) is a method of ''composition'' imaging based on measurements of diffraction patterns from tissues. Use of an x-ray tube degrades scatter pattern angular resolution due to the x-ray spectral width, making it difficult to uniquely identify some materials. The use of two transmission filters with similar atomic numbers (balanced ''Ross filters'') to generate pseudomonoenergetic scatter patterns is described as it applies to CSCT. An analysis of angular-blur mechanisms reveals that focal spot size and beam width are the most important factors determining Bragg-peak width when Er-Tm filters are used. A relative RMS spectral width of 1% can be achieved in the difference spectrum and a Bragg-peak RMS angular width of approximately 0.14 deg. (relative width of 3% at 5 deg. scatter angle) can be achieved with an effective energy of 58 keV.

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

    PubMed

    Hopkins, Mark; Blundell, John E

    2016-09-01

    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 demonstrated that resting metabolic rate (RMR) is a potential driver of energy intake, and evidence is accumulating on the influence of physical activity (behavioural energy expenditure) on mechanisms of satiety and appetite control. These effects are associated with changes in leptin and insulin sensitivity, and in the plasma levels of gastrointestinal (GI) peptides such as glucagon-like peptide-1 (GLP-1), ghrelin and cholecystokinin (CCK). The influence of fat-free mass on energy expenditure and as a driver of energy intake directs attention to molecules emanating from skeletal tissue as potential appetite signals. Sedentariness (physical inactivity) is positively associated with adiposity and is proposed to be a source of overconsumption and appetite dysregulation. The molecular signals underlying these effects are not known but represent a target for research.

  12. How many stakes are required to measure the mass balance of a glacier?

    USGS Publications Warehouse

    Fountain, A.G.; Vecchia, A.

    1999-01-01

    Glacier mass balance is estimated for South Cascade Glacier and Maclure Glacier using a one-dimensional regression of mass balance with altitude as an alternative to the traditional approach of contouring mass balance values. One attractive feature of regression is that it can be applied to sparse data sets where contouring is not possible and can provide an objective error of the resulting estimate. Regression methods yielded mass balance values equivalent to contouring methods. The effect of the number of mass balance measurements on the final value for the glacier showed that sample sizes as small as five stakes provided reasonable estimates, although the error estimates were greater than for larger sample sizes. Different spatial patterns of measurement locations showed no appreciable influence on the final value as long as different surface altitudes were intermittently sampled over the altitude range of the glacier. Two different regression equations were examined, a quadratic, and a piecewise linear spline, and comparison of results showed little sensitivity to the type of equation. These results point to the dominant effect of the gradient of mass balance with altitude of alpine glaciers compared to transverse variations. The number of mass balance measurements required to determine the glacier balance appears to be scale invariant for small glaciers and five to ten stakes are sufficient.

  13. Energy balance in the ablation zone during the summer season at the Gran Campo Nevado Ice Cap in the Southern Andes

    NASA Astrophysics Data System (ADS)

    Schneider, Christoph; Kilian, Rolf; Glaser, Michael

    2007-10-01

    The energy balance and ablation of Glaciar Lengua were investigated during the austral summer of 1999/2000. Glaciar Lengua is located in Patagonia, in the southernmost Andes of Chile (53°S), within an extremely maritime climate. The aim of this study was to gain insight into current energy fluxes at this location and to evaluate how the energy fluxes depend on meteorological variables. From February to April 2000 an automated weather station was operated on Glaciar Lengua. Ablation was measured repeatedly at stakes during the same period. The point energy balance was calculated using the bulk approach formulation. The effective roughness length was adjusted in order to calibrate the model to the measured ablation. It was revealed that sensible heat transfer is the major contribution to the energy balance adding 54% of the energy available for melt. Net radiation contributes only 35% to the overall energy balance. Minor contributors are the latent heat flux (7%) and the heat flux by precipitation (4%). The net radiation shows little variance from day to day. Cross-correlations of the daily mean values of the energy fluxes derived from the energy balance model and meteorological variables reveal that air temperature and wind speed are the key factors controlling the summer energy balance in the ablation area. Melt derived from a multiple regression model based on these two variables correlates with computed melt with a correlation coefficient of 0.92. From the measured ablation, a summer-time degree-day factor of 7.6 mm·°C - 1 was derived for the ablation area.

  14. Energy balance and turbulent flux partitioning in a corn-soybean rotation in the Midwestern US

    NASA Astrophysics Data System (ADS)

    Hernandez-Ramirez, Guillermo; Hatfield, Jerry L.; Prueger, John H.; Sauer, Thomas J.

    2010-03-01

    Quantifying the energy balance above plant canopies is critical for better understanding of water balance and changes in regional weather patterns. This study examined temporal variations of energy balance terms for contrasting canopies [corn ( Zea mays L.) and soybean ( Glycine max L. Merr.)]. We monitored energy balance for 4 years using eddy-covariance systems, net radiometers, and soil heat flux plates in adjacent production fields near Ames, Iowa. On an annual basis, soybean exhibited 20% and 30% lower sensible heat flux ( H) and Bowen ratio than corn, respectively. As canopies developed, a gradual shift in turbulent fluxes occurred with decreasing H and increasing latent heat flux (LE), but with a more pronounced effect for corn. Conversely, during mid-growing season and as both canopies progressively senesced, H in general increased and LE decreased; however, soybean exhibited slightly greater LE and much lower H than corn. These temporal variations in magnitude and partitioning of turbulent fluxes translated into a pronounced energy imbalance for soybean (0.80) and an enhanced closure for corn (0.98) in August and September. These discrepancies could be directly associated with differences in momentum transport as shown by friction velocities of 0.34 and 0.28 m s-1 for corn and soybean, respectively. These results support influential roles of plant canopy on intensity and mode of surface energy exchange processes.

  15. Energy balance in the watershed of Ipê, Northwestern São Paulo State, Brazil

    NASA Astrophysics Data System (ADS)

    Feitosa, Diego G.; T. Hernandez, Fernando B.; Franco, Renato A. M.; Teixeira, Antonio H. C.; Neale, Christopher M.

    2016-10-01

    The region of Ilha Solteira, in the Northwestern of São Paulo State, has been undergoing significant changes in agricultural land use and cover since 2006, as pasture fields have been replaced by sugarcane crop. This drastic change can lead to a disturbance in the energy balance, affecting the local climate. The aim of this paper was to assess some parameters related to the energy balance of Ipê's watershed, that changed since no sugarcane cultivation in 2006 to 2,164 hectares in 2011, occupying 31% of the catchment area with this important energy crop for the economy and the environment of Brazil. This study was carried out using remote sensing combined with weather data and using the SAFER (Simple Algorithm for Retrieving Evapotranspiration) model applied in 9 Landsat images collected between 2003 and 2011. The results showed a wide variation between the components of energy balance and when considering only the sugarcane crop were verified the increase values of ETa (Actual Evapotranspiration), H/Rn (Sensible Heat Flux/Net Radiation), TS (Surface Temperature), Rl↑ (Emitted longwave), Rl↓ (Incidente longwave) and surface albedo after the sugarcane production over these years. On the other hand, the NDVI, λE/Rn (Latent Heat Flux/Net Radiation) and Rn values (data) decreased in the same period. Also there was satisfactory correlation between NDVI and ETa. The SAFER model showed satisfactory results for studies of energy balance applied in the Northwestern of São Paulo State.

  16. Skeletal muscle responses to negative energy balance: effects of dietary protein.

    PubMed

    Carbone, John W; McClung, James P; Pasiakos, Stefan M

    2012-03-01

    Sustained periods of negative energy balance decrease body mass due to losses of both fat and skeletal muscle mass. Decreases in skeletal muscle mass are associated with a myriad of negative consequences, including suppressed basal metabolic rate, decreased protein turnover, decreased physical performance, and increased risk of injury. Decreases in skeletal muscle mass in response to negative energy balance are due to imbalanced rates of muscle protein synthesis and degradation. However, the underlying physiological mechanisms contributing to the loss of skeletal muscle during energy deprivation are not well described. Recent studies have demonstrated that consuming dietary protein at levels above the current recommended dietary allowance (0.8 g · kg(-1) · d(-1)) may attenuate the loss of skeletal muscle mass by affecting the intracellular regulation of muscle anabolism and proteolysis. However, the specific mechanism by which increased dietary protein spares skeletal muscle through enhanced molecular control of muscle protein metabolism has not been elucidated. This article reviews the available literature related to the effects of negative energy balance on skeletal muscle mass, highlighting investigations that assessed the influence of varying levels of dietary protein on skeletal muscle protein metabolism. Further, the molecular mechanisms that may contribute to the regulation of skeletal muscle mass in response to negative energy balance and alterations in dietary protein level are described.

  17. Comparison of Objective Measures for Predicting Perceptual Balance and Visual Aesthetic Preference

    PubMed Central

    Hübner, Ronald; Fillinger, Martin G.

    2016-01-01

    The aesthetic appreciation of a picture largely depends on the perceptual balance of its elements. The underlying mental mechanisms of this relation, however, are still poorly understood. For investigating these mechanisms, objective measures of balance have been constructed, such as the Assessment of Preference for Balance (APB) score of Wilson and Chatterjee (2005). In the present study we examined the APB measure and compared it to an alternative measure (DCM; Deviation of the Center of “Mass”) that represents the center of perceptual “mass” in a picture and its deviation from the geometric center. Additionally, we applied measures of homogeneity and of mirror symmetry. In a first experiment participants had to rate the balance and symmetry of simple pictures, whereas in a second experiment different participants rated their preference (liking) for these pictures. In a third experiment participants rated the balance as well as the preference of new pictures. Altogether, the results show that DCM scores accounted better for balance ratings than APB scores, whereas the opposite held with respect to preference. Detailed analyses revealed that these results were due to the fact that aesthetic preference does not only depend on balance but also on homogeneity, and that the APB measure takes this feature into account. PMID:27014143

  18. Mass and energy balance constraints on the biological production of chemicals from coal

    SciTech Connect

    Andrews, G.

    1990-01-01

    Several organic chemicals, including methane and ethanol, may be produced by the bioprocessing of coal. This may be done either by direct microbial attack on the coal, or indirectly by the bioprocessing of solubilized coal. As in chemical liquefaction and gasification, the relative amounts of the various products that can be produced are severely constrained by mass and energy balance considerations. The main differences in biological processing are that water is a ubiquitous reactant, carbon dioxide a common product, and that some of the carbon and nitrogen in the coal may go to the synthesis of new biomass rather than products. The conventional biotechnological yield analysis applied to coal processing has several interesting consequences. The mass balance reduces to a balance of available electrons, and coal has a similar oxidation/reduction state to both carbohydrates and biomass. This makes high product yields feasible particularly under anaerobic conditions, although leaving open the question of whether the relevant hydrolase enzymes exist. Recommendations are made on products, and combinations of two products, that may be made with high yields and economic return. The energy balance provides little extra information. A general intracellular energy balance can be written in terms of the production and consumption of ATP, but much of the necessary information on the metabolic pathways is currently not available for coal processing microorganisms. 9 refs., 2 figs., 2 tabs.

  19. Modelling the snowmelt and the snow water equivalent by creating a simplified energy balance conceptual snow model

    NASA Astrophysics Data System (ADS)

    Riboust, Philippe; Thirel, Guillaume; Le Moine, Nicolas; Ribstein, Pierre

    2016-04-01

    A better knowledge of the accumulated snow on the watersheds will help flood forecasting centres and hydro-power companies to predict the amount of water released during spring snowmelt. Since precipitations gauges are sparse at high elevations and integrative measurements of the snow accumulated on watershed surface are hard to obtain, using snow models is an adequate way to estimate snow water equivalent (SWE) on watersheds. In addition to short term prediction, simulating accurately SWE with snow models should have many advantages. Validating the snow module on both SWE and snowmelt should give a more reliable model for climate change studies or regionalization for ungauged watersheds. The aim of this study is to create a new snow module, which has a structure that allows the use of measured snow data for calibration or assimilation. Energy balance modelling seems to be the logical choice for designing a model in which internal variables, such as SWE, could be compared to observations. Physical models are complex, needing high computational resources and many different types of inputs that are not widely measured at meteorological stations. At the opposite, simple conceptual degree-day models offer to simulate snowmelt using only temperature and precipitation as inputs with fast computing. Its major drawback is to be empirical, i.e. not taking into account all of the processes of the energy balance, which makes this kind of model more difficult to use when willing to compare SWE to observed measurements. In order to reach our objectives, we created a snow model structured by a simplified energy balance where each of the processes is empirically parameterized in order to be calculated using only temperature, precipitation and cloud cover variables. This model's structure is similar to the one created by M.T. Walter (2005), where parameterizations from the literature were used to compute all of the processes of the energy balance. The conductive fluxes into the

  20. Calibration of an Energy Water Balance Model Using Satellite Data of Land Surface Temperature for the Upper Yangtze River Basin

    NASA Astrophysics Data System (ADS)

    Corbari, Chiara, Mancini, Marco; Li, Jiren; Su, Bob

    2013-01-01

    This study has been carried out among the project “Application of remote sensing and other space technology to hydrology and water resources (ID 5281)”. This poster presents a new methodology for the calibration of distributed hydrological models at basin scale by constraining an internal model variable, the pixel-scale equilibrium temperature. Soil hydraulic and vegetation parameters are then calibrated in each pixel of the domain according to the comparison between observed and simulated land surface temperature minimizing the differences. The model algorithm solves the system of energy and mass balances in terms of a representative equilibrium temperature (RET) that is the land surface temperature that closes the energy balance equation and so governs the fluxes of energy and mass over the basin domain. This equilibrium surface temperature, which is a critical model state variable, is comparable to LST as retrieved from operational remote sensing data (MODIS and AATSR). A traditional “trial and error” calibration procedure is also applied by comparing only discharge measurements in the available cross section. The distributed hydrological energy water balance model (FEST-EWB - Flash-flood Event-based Spatially-distributed rainfall-runoff Transformation- Energy Water Balance) has been implemented for the Upper Yangtze River basin with an extent of about 1,000,000 Km2 at spatial resolution of 5km and temporal resolution of 1 hour. Results are provided in terms of hourly evapotranspiration, soil moisture and land surface temperature maps for the period between 2000 to 2004 where ground and satellite data are available for engineering and environmental applications as parsimonious irrigation, real time flood forecast, and quantitative water resources availability. The model accuracy was controlled from the comparison with traditional discharge daily data series and also from the comparison between model and satellite land surface temperature used as a proxy

  1. Energy balance of a high marsh on the Texas Gulf Coast: Effect of water availability

    NASA Astrophysics Data System (ADS)

    Heilman, J. L.; Heinsch, F. A.; Cobos, D. R.; McInnes, K. J.

    2000-09-01

    The supply of water to the Nueces River Delta near Corpus Christi, Texas, and its estuarine marshes is limited by low tidal ranges in the Gulf of Mexico and by channelization of the Nueces River which restricts freshwater inflow. Micrometeorological measurements were made at the upper end (high marsh) of the delta to determine how daily and seasonal changes in the surface energy balance were affected by availability of water. The marsh consists of shallow ponds interconnected by narrow channels, and elevated areas containing emergent vegetation. During the spring and fall when ponds were flooded, latent and sensible heat flux averaged 67% and 30%, respectively, of net radiation. In the summer when ponds dried, energy partitioning was reversed with sensible heat flux accounting for 65% of net radiation and latent heat accounting for 27%. When ponds were flooded, heat storage in the water column was the major component of storage heat flux. When ponds dried, storage heat flux was controlled by sediment water content, largely through its effect on thermal diffusivity. The ratio of actual to equilibrium evaporation averaged 0.7 in the spring and fall, and 0.3 in the summer, indicating that the marsh behaved more like a dryland ecosystem than a wetland.

  2. Prenatal stress programming of offspring feeding behavior and energy balance begins early in pregnancy.

    PubMed

    Pankevich, Diana E; Mueller, Bridget R; Brockel, Becky; Bale, Tracy L

    2009-08-04

    To examine the long-term effects of stress experienced early in gestation on the programming of offspring feeding behaviors and energy balance, pregnant mice were exposed to stress during early pregnancy (days 1-7) and adult offspring examined on chow and high fat diets for long-term outcomes. Placental 11 beta-hydroxysteroid dehydrogenase type 2 (11 beta-HSD2) and insulin-like growth factor 2 (IGF-2) expression was measured to determine the possible sex-specific contribution of prenatal stress (PNS) on fetal programming of embryo growth and development during early pregnancy. PNS mice showed a basal hyperphagia when on chow diet. Prenatal treatment differences were ameliorated when adult mice were on a high fat diet. Interestingly, PNS male mice also had significantly reduced body weights compared to control males on both chow and high fat diets. Body composition analyses revealed reduced body fat and increased lean mass in PNS mice on the high fat diet, but no differences were detected in plasma leptin or insulin-like growth factor 1 (IGF-1) levels. Mechanistic examination of gene expression in embryonic day 12 placentas found that early PNS was associated with increased IGF-2 expression and sex-dependent effects of stress on 11 beta-HSD2, supporting specific aspects of early pregnancy. These studies suggest that the long-term effects of stress during pregnancy on programming of feeding behavior and energy homeostasis begin much earlier in development than previously thought.

  3. Energy balance of a wheat canopy under elevated and ambient CO 2 concentrations

    NASA Astrophysics Data System (ADS)

    Frumau, K. F. A.; Vugts, H. F.

    1996-05-01

    An experiment was performed during the full growing season of wheat to determine the direct effects of atmospheric CO 2 enrichment on the energy balance of a wheat crop at ample levels of water under natural field conditions using the Free-Air CO 2 Enrichment (FACE) approach. It is found that the net radiation in FACE is higher by 0.9% at anthesis and is decreased compared to CONTROL during the grain filling period following anthesis and is lower by 3.6% at the start of senescence. This trend is supported by separate short-wave radiation and canopy temperature measurements. The albedo at FACE is lower by 1.9% at the start and higher by 0.89% at the end of this period, whereas canopy temperature at FACE is higher by 0.83°C and 0.48°C at the start and end of this period respectively. As soil heat flux differences are negligible, the available energy for partitioning between sensible and latent heat flux under elevated and ambient CO 2 conditions follows the same trend. During both stable and unstable conditions the latent heat flux is suppressed, whereas the sensible heat flux is enhanced during unstable and suppressed during stable conditions inside the FACE plot compared to the CONTROL plot.

  4. Closure of the energy balance equation over bare soil during the formation and evaporation of non-rainfall water inputs

    NASA Astrophysics Data System (ADS)

    Florentin, Anat; Agam, Nurit

    2015-04-01

    The Negev desert is characterized by an arid climate (annual mean precipitation is 90 mm) with sea breeze carrying moisture from the Mediterranean Sea during the afternoon regularly. Non-rainfall water inputs (NRWIs) are thus of great importance to the hydrometeorology and the ecological functioning of the region. The small magnitude of NRWIs challenges attempts to quantify these processes. The aim of this research was to test commonly used micrometeorological methods to quantify the energy balance components during the deposition and evaporation of NRWIs. A fully equipped micrometeorological station was set up near the Blaustein Institutes for Desert Research of the Ben-Gurion University of the Negev (30o 51' 35.6" N; 34o 46' 24.8" E) during September-October 2014. Net-radiation was measured with a 4-way net radiometer, and soil heat flux was quantified by the calorimetric method in three replicates. Latent heat was measured using an eddy-covariance (EC) and compared to a micro-lysimeter (ML); sensible heat flux was measured with an EC and a surface layer scintillometer (SLS). Sensible heat fluxes measured by the EC and the SLS showed good agreement. EC latent heat fluxes were in good agreement with those derived by the ML. Nevertheless, derivation of latent heat flux from the SLS measurements through the energy balance equation showed a relatively large deviation from the directly measured latent heat flux. This deviation is likely attributed to measurement errors of the soil heat flux.

  5. Energy balance, metabolism, hydration, and performance during strenuous hill walking: the effect of age.

    PubMed

    Ainslie, P N; Campbell, I T; Frayn, K N; Humphreys, S M; MacLaren, D P M; Reilly, T; Westerterp, K R

    2002-08-01

    We aimed to examine the effect of age on energy balance, metabolism, hydration, and performance during 10 days of strenuous hill walking. Seventeen male subjects were divided into two groups according to their age. The nine subjects in group 1 constituted the younger group (age 24 +/- 3 yr), whereas eight older subjects were in group 2 (age 56 +/- 3 yr). Both groups completed 10 consecutive days of high-intensity hill walking. Mean (range) daily walking distances and ascent were 21 km (10-35 km) and 1,160 m (800-2,540 m), respectively. Energy intake was calculated from weighed food intake, and energy expenditure was measured by the doubly labeled water method. Blood and urine were sampled on alternative days to determine any changes in metabolism and hydration during the 10 days. Subjects also completed a battery of tests that included muscular strength (handgrip), jump performance, cognitive processing time, and flexibility. The younger group remained hydrated, whereas the older group became progressively dehydrated, indicated by a near twofold increase in urine osmolality concentration on day 11. This increased urine osmolality in the older group was highly correlated with impairment in vertical-jump performance (r = -0.86; P < 0.05) and decreased cognitive processing time (r = 0.79; P < 0.05). Despite energy expenditure of approximately 21 MJ/day, body mass was well maintained in both groups. Both groups displayed a marked increase in fat mobilization, reflected in significantly lowered prewalk insulin concentrations and elevated postwalk glycerol and nonesterified fatty acid concentrations. Despite the dehydration and impaired performance in the older group, blood glucose concentrations were well maintained in both groups, probably mediated via the increased mobilization of fat.

  6. A force balance system for the measurement of skin friction drag force

    NASA Technical Reports Server (NTRS)

    Moore, J. W.; Mcvey, E. S.

    1971-01-01

    Research on force balance instrumentation to measure the skin friction of hypersonic vehicles at extreme temperatures, high altitudes and in a vibration field is discussed. A rough overall summary and operating instructions for the equipment are presented.

  7. Improving the XAJ Model on the Basis of Mass-Energy Balance

    NASA Astrophysics Data System (ADS)

    Fang, Yuanghao; Corbari, Chiara; Zhang, Xingnan; Mancini, Marco

    2014-11-01

    The Xin’anjiang(XAJ) model is a conceptual model developed by the group led by Prof. Ren-Jun Zhao, which takes the pan evaporation as one of its input and then computes the effective evapotranspiration (ET) of the catchment by mass balance. Such scheme can ensure a good performance of discharge simulation but has obvious defects, one of which is that the effective ET is spatially-constant over the computation unit, neglecting the spatial variation of variables that influence the effective ET and therefore the simulation of ET and SM by the XAJ model, comparing with discharge, is less reliable. In this study, The XAJ model was improved to employ both energy and mass balance to compute the ET following the energy-mass balance scheme of FEST-EWB. model.

  8. Improving the XAJ Model on the Basis of Mass-Energy Balance

    NASA Astrophysics Data System (ADS)

    Fang, Yuanhao; Corbari, Chiara; Zhang, Xingnan; Mancini, Marco

    2014-11-01

    Introduction: The Xin'anjiang(XAJ) model is a conceptual model developed by the group led by Prof. Ren-Jun Zhao, which takes the pan evaporation as one of its input and then computes the effective evapotranspiration (ET) of the catchment by mass balance. Such scheme can ensure a good performance of discharge simulation but has obvious defects, one of which is that the effective ET is spatially-constant over the computation unit, neglecting the spatial variation of variables that influence the effective ET and therefore the simulation of ET and SM by the XAJ model, comparing with discharge, is less reliable. In this study, The XAJ model was improved to employ both energy and mass balance to compute the ET following the energy-mass balance scheme of FEST-EWB. model.

  9. Energy and greenhouse gas balances for a solid waste incineration plant: a case study.

    PubMed

    Brinck, Kim; Poulsen, Tjalfe G; Skov, Henrik

    2011-10-01

    Energy and greenhouse gas balances for a waste incineration plant (Reno-Nord I/S, Aalborg, Denmark) as a function of time over a 45-year period beginning 1960 are presented. The quantity of energy recovered from the waste increased over time due to increasing waste production, increasing lower heating value of the waste and implementation of improved energy recovery technology at the incineration plant. Greenhouse gas (GHG) balances indicated progressively increasing GHG savings during the time period investigated as a result of the increasing energy production. The GHG balances show that the Reno-Nord incineration plant has changed from a net annual GHG emission of 30 kg CO(2)-eq person(-1) year(-1) to a net annual GHG saving of 770 kg CO(2)-eq person(-1) year(-1) which is equivalent to approximately 8% of the annual emission of GHG from an average Danish person (including emissions from industry and transport). The CO(2) emissions associated with combustion of the fossil carbon contained in the waste accounted for about two-thirds of the GHG turnover when no energy recovery is applied but its contribution reduces to between 10 and 15% when energy recovery is implemented. The reason being that energy recovery is associated with a large CO(2) saving (negative emission).

  10. Energy balance in the solar transition region. II - Effects of pressure and energy input on hydrostatic models

    NASA Technical Reports Server (NTRS)

    Fontenla, J. M.; Avrett, E. H.; Loeser, R.

    1991-01-01

    The radiation of energy by hydrogen lines and continua in hydrostatic energy-balance models of the transition region between the solar chromosphere and corona is studied using models which assume that mechanical or magnetic energy is dissipated in the hot corona and is then transported toward the chromosphere down the steep temperature gradient of the transition region. These models explain the average quiet sun and also the entire range of variability of the Ly-alpha lines. The relations between the downward energy flux, the pressure of the transition region, and the different hydrogen emission are described.

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

    NASA Astrophysics Data System (ADS)

    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

  12. Measurement of surface physical properties and radiation balance for KUREX-91 study

    NASA Technical Reports Server (NTRS)

    Walter-Shea, Elizabeth A.; Blad, Blaine L.; Mesarch, Mark A.; Hays, Cynthia J.

    1992-01-01

    Biophysical properties and radiation balance components were measured at the Streletskaya Steppe Reserve of the Russian Republic in July 1991. Steppe vegetation parameters characterized include leaf area index (LAI), leaf angle distribution, mean tilt angle, canopy height, leaf spectral properties, leaf water potential, fraction of absorbed photosynthetically active radiation (APAR), and incoming and outgoing shortwave and longwave radiation. Research results, biophysical parameters, radiation balance estimates, and sun-view geometry effects on estimating APAR are discussed. Incoming and outgoing radiation streams are estimated using bidirectional spectral reflectances and bidirectional thermal emittances. Good agreement between measured and modeled estimates of the radiation balance were obtained.

  13. 30 CFR 817.45 - Hydrologic balance: Sediment control measures.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... limitations, (3) Minimize erosion to the extent possible. (b) Sediment control measures include practices... reclamation techniques are applied to reduce erosion and control sediment. Sediment control measures consist... protected channels or pipes through disturbed areas so as not to cause additional erosion; (6) Using...

  14. 30 CFR 816.45 - Hydrologic balance: Sediment control measures.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... limitations, (3) Minimize erosion to the extent possible. (b) Sediment control measures include practices... reclamation techniques are applied to reduce erosion and control sediment. Sediment control measures consist... protected channels or pipes through disturbed areas so as not to cause additional erosion; (6) Using...

  15. 30 CFR 817.45 - Hydrologic balance: Sediment control measures.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... limitations, (3) Minimize erosion to the extent possible. (b) Sediment control measures include practices... reclamation techniques are applied to reduce erosion and control sediment. Sediment control measures consist... protected channels or pipes through disturbed areas so as not to cause additional erosion; (6) Using...

  16. 30 CFR 817.45 - Hydrologic balance: Sediment control measures.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... limitations, (3) Minimize erosion to the extent possible. (b) Sediment control measures include practices... reclamation techniques are applied to reduce erosion and control sediment. Sediment control measures consist... protected channels or pipes through disturbed areas so as not to cause additional erosion; (6) Using...

  17. 30 CFR 817.45 - Hydrologic balance: Sediment control measures.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... limitations, (3) Minimize erosion to the extent possible. (b) Sediment control measures include practices... reclamation techniques are applied to reduce erosion and control sediment. Sediment control measures consist... protected channels or pipes through disturbed areas so as not to cause additional erosion; (6) Using...

  18. 30 CFR 816.45 - Hydrologic balance: Sediment control measures.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... limitations, (3) Minimize erosion to the extent possible. (b) Sediment control measures include practices... reclamation techniques are applied to reduce erosion and control sediment. Sediment control measures consist... protected channels or pipes through disturbed areas so as not to cause additional erosion; (6) Using...

  19. 30 CFR 816.45 - Hydrologic balance: Sediment control measures.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... limitations, (3) Minimize erosion to the extent possible. (b) Sediment control measures include practices... reclamation techniques are applied to reduce erosion and control sediment. Sediment control measures consist... protected channels or pipes through disturbed areas so as not to cause additional erosion; (6) Using...

  20. 30 CFR 817.45 - Hydrologic balance: Sediment control measures.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... limitations, (3) Minimize erosion to the extent possible. (b) Sediment control measures include practices... reclamation techniques are applied to reduce erosion and control sediment. Sediment control measures consist... protected channels or pipes through disturbed areas so as not to cause additional erosion; (6) Using...

  1. 30 CFR 816.45 - Hydrologic balance: Sediment control measures.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... limitations, (3) Minimize erosion to the extent possible. (b) Sediment control measures include practices... reclamation techniques are applied to reduce erosion and control sediment. Sediment control measures consist... protected channels or pipes through disturbed areas so as not to cause additional erosion; (6) Using...

  2. 30 CFR 816.45 - Hydrologic balance: Sediment control measures.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... limitations, (3) Minimize erosion to the extent possible. (b) Sediment control measures include practices... reclamation techniques are applied to reduce erosion and control sediment. Sediment control measures consist... protected channels or pipes through disturbed areas so as not to cause additional erosion; (6) Using...

  3. Managing the "Measure Up Monster": Leadership in the Balance

    ERIC Educational Resources Information Center

    Sullivan, Debra

    2010-01-01

    The "Measure Up Monster" usually comes to visit wearing one of two disguises. Its favorite disguise is "Flattery". Some say flattery will get a person everything, but sometimes flattery only gets a person frightened. When the "Measure Up Monster" shows up disguised as Flattery it can feel like a set up for failure. That's because sometimes people…

  4. Comparison of computational methods for estimation of energy balance of building envelopes

    NASA Astrophysics Data System (ADS)

    Kočí, Václav; Černý, Robert

    2013-10-01

    Two calculation methods of annual energy balance of building envelopes are presented in this paper. As reference building envelope, single-layer autoclaved aerated concrete masonry is chosen. The first calculation method is based on simplified standard procedure, the second method on results of more sophisticated hygrothermal simulation under realistic climatic conditions. Both results are compared and analyzed.

  5. Ninth Graders' Energy Balance Knowledge and Physical Activity Behavior: An Expectancy-Value Perspective

    ERIC Educational Resources Information Center

    Chen, Senlin; Chen, Ang

    2012-01-01

    Expectancy beliefs and task values are two essential motivators in physical education. This study was designed to identify the relation between the expectancy-value constructs (Eccles & Wigfield, 1995) and high school students' physical activity behavior as associated with their energy balance knowledge. High school students (N = 195) in two…

  6. Alternative Resources for Curriculum Balance in Nutrition, Economics, Energy, Environmental, Consumer & Citizenship Education.

    ERIC Educational Resources Information Center

    Harty, Sheila, Comp.

    This annotated directory lists selected informational and educational resources in the subject areas predominant in corporate education efforts. Organized by categories of nutrition, economics, energy, environmental consumer and citizenship education, this list is intended to help provide a balance of resources and perspectives for the classroom…

  7. Changes in Energy Balance Following Smoking Cessation and Resumption of Smoking in Women.

    ERIC Educational Resources Information Center

    Perkins, Kenneth A.; And Others

    1990-01-01

    Prospectively examined caloric intake, resting metabolic rate (RMR), leisure time physical activity, and sensitivity and preference for sweet taste in seven female smokers during normal smoking, complete cessation, and resumption of smoking. Findings suggest that smoking cessation may cause rapid change in energy balance which is quickly reversed…

  8. Improved Student Achievement Using Personalized Online Homework for a Course in Material and Energy Balances

    ERIC Educational Resources Information Center

    Liberatore, Matthew W.

    2011-01-01

    Personalized, online homework was used to supplement textbook homework, quizzes, and exams for one section of a course in material and energy balances. The objective of this study was to test the hypothesis that students using personalized, online homework earned better grades in the course. The online homework system asks the same questions of…

  9. The Martian climate: Energy balance models with CO2/H2O atmospheres

    NASA Technical Reports Server (NTRS)

    Hoffert, M. I.

    1985-01-01

    Coupled equations are developed for mass and heat transport in a seasonal Mars model with condensation and sublimation of CO2 at the polar caps. Topics covered include physical considerations of planetary as mass and energy balance; effects of phase changes at the surface on mass and heat flux; atmospheric transport and governing equations; and numerical analysis.

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

    USGS Publications Warehouse

    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 (<0.93 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.

  11. Active Learning and Just-in-Time Teaching in a Material and Energy Balances Course

    ERIC Educational Resources Information Center

    Liberatore, Matthew W.

    2013-01-01

    The delivery of a material and energy balances course is enhanced through a series of in-class and out-of-class exercises. An active learning classroom is achieved, even at class sizes over 150 students, using multiple instructors in a single classroom, problem solving in teams, problems based on YouTube videos, and just-in-time teaching. To avoid…

  12. Across-phase biomass pyrolysis stoichiometry, energy balance, and product formation kinetics

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Predictive correlations between reactions occurring in the gas-, liquid- and solid-phases are necessary to economically utilize the thermochemical conversion of agricultural wastes impacting the food, water, and energy nexus. On the basis of an empirical mass balance (99.7%), this study established...

  13. Breath carbon stable isotope ratios identify changes in energy balance and substrate utilization in humans

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rapid detection of shifts in substrate utilization and energy balance would provide a compelling biofeedback tool to enable individuals to lose weight. In a pilot study, we tested whether the natural abundance of exhaled carbon stable isotope ratios (breath d13C values) reflects shifts between negat...

  14. Enhancing Energy Balance Education through Physical Education and Self-Monitoring Technology

    ERIC Educational Resources Information Center

    Chen, Senlin; Zhu, Xihe; Kim, Youngwon; Welk, Gregory; Lanningham-Foster, Lorraine

    2016-01-01

    Schools are positioned to play a key role in nurturing students with knowledge and behaviours associated with healthful living. Our study examined the effects of an intervention on energy balance (EB) knowledge. Twelve 6th and 7th grade classrooms (n = 140) were assigned to receive either two standardised lessons on EB or a combined intervention…

  15. Application of radiometric surface temperature for surface energy balance estimation: John Monteith's contributions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Over 25 years ago, Huband and Monteith paper’s investigating the radiative surface temperature and the surface energy balance of a wheat canopy, highlighted the key issues in computing fluxes with radiometric surface temperature. These included the relationship between radiometric and aerodynamic s...

  16. Effect of dietary energy source on energy balance, production, metabolic disorders and reproduction in lactating dairy cattle.

    PubMed

    van Knegsel, Ariëtte T M; van den Brand, Henry; Dijkstra, Jan; Tamminga, Seerp; Kemp, Bas

    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 products required for milk production. This review compares studies which manipulated dietary energy source and shows that dietary energy source can affect the balance of the C2/C3 ratio, as indicated by plasma NEFA, beta-hydroxybutyrate (BHBA) and glucose levels. It is shown that glycogenic nutrients increase glucose and insulin concentrations and decrease NEFA and BHBA plasma levels. Extra lipogenic nutrients elevate NEFA and BHBA and decrease plasma glucose concentrations. Lipogenic nutrients generally increase milk fat percentage and decrease milk protein percentage, suggesting a surplus of C2 compounds. The inverse is the case for feeding extra glycogenic nutrients, implying reduced deamination and oxidation of glycogenic amino acids. Feeding extra glycogenic nutrients improved the energy balance (EB), in contrast to ambiguous results of lipogenic nutrients on EB. Moreover, glycogenic feed may reduce the severity of ketosis and fatty liver, but increased the incidence of (sub)clinical acidosis. Since studies are scarce, it seems difficult to draw conclusions on the effects of dietary energy source on reproduction. However, lipogenic nutrients decrease glucose and increase NEFA and BHBA plasma levels. High plasma NEFA and BHBA and low plasma glucose levels are associated with decreased reproductive performance, which might imply the C2/C3 compound balance to be important for reproductive function.

  17. Mass-balance measurements in Alaska and suggestions for simplified observation programs

    USGS Publications Warehouse

    Trabant, D.C.; March, R.S.

    1999-01-01

    US Geological Survey glacier fieldwork in Alaska includes repetitious measurements, corrections for leaning or bending stakes, an ability to reliably measure seasonal snow as deep as 10 m, absolute identification of summer surfaces in the accumulation area, and annual evaluation of internal accumulation, internal ablation, and glacier-thickness changes. Prescribed field measurement and note-taking techniques help eliminate field errors and expedite the interpretative process. In the office, field notes are transferred to computerized spread-sheets for analysis, release on the World Wide Web, and archival storage. The spreadsheets have error traps to help eliminate note-taking and transcription errors. Rigorous error analysis ends when mass-balance measurements are extrapolated and integrated with area to determine glacier and basin mass balances. Unassessable errors in the glacier and basin mass-balance data reduce the value of the data set for correlations with climate change indices. The minimum glacier mass-balance program has at least three measurement sites on a glacier and the measurements must include the seasonal components of mass balance as well as the annual balance.

  18. Public Interest Energy Research (PIER) Program. Final Project Report. California Energy Balance Update and Decomposition Analysis for the Industry and Building Sectors

    SciTech Connect

    de la Rue du Can, Stephane; Hasanbeigi, Ali; Sathaye, Jayant

    2010-12-01

    This report on the California Energy Balance version 2 (CALEB v2) database documents the latest update and improvements to CALEB version 1 (CALEB v1) and provides a complete picture of how energy is supplied and consumed in the State of California. The CALEB research team at Lawrence Berkeley National Laboratory (LBNL) performed the research and analysis described in this report. CALEB manages highly disaggregated data on energy supply, transformation, and end-use consumption for about 40 different energy commodities, from 1990 to 2008. This report describes in detail California's energy use from supply through end-use consumption as well as the data sources used. The report also analyzes trends in energy demand for the "Manufacturing" and "Building" sectors. Decomposition analysis of energy consumption combined with measures of the activity driving that consumption quantifies the effects of factors that shape energy consumption trends. The study finds that a decrease in energy intensity has had a very significant impact on reducing energy demand over the past 20 years. The largest impact can be observed in the industry sector where energy demand would have had increased by 358 trillion British thermal units (TBtu) if subsectoral energy intensities had remained at 1997 levels. Instead, energy demand actually decreased by 70 TBtu. In the "Building" sector, combined results from the "Service" and "Residential" subsectors suggest that energy demand would have increased by 264 TBtu (121 TBtu in the "Services" sector and 143 TBtu in the "Residential" sector) during the same period, 1997 to 2008. However, energy demand increased at a lesser rate, by only 162 TBtu (92 TBtu in the "Services" sector and 70 TBtu in the "Residential" sector). These energy intensity reductions can be indicative of energyefficiency improvements during the past 10 years. The research presented in this report provides a basis for developing an energy-efficiency performance index to measure

  19. Energy balance of a plasma with a wave, taking the wave nonpotentiality into account

    NASA Astrophysics Data System (ADS)

    Gelberg, M. G.; Volosevich, A. V.

    It is shown that the potential electric field of low-frequency plasma waves in the ionosphere is phase-shifted by approximately -pi/2 with respect to current fluctuations, while the vortex field is nearly cophase with the current. Thus, the work of energy transfer between the plasma and the wave occurs primarily with the participation of the vortex field. The wave nonpotentiality is shown to have a substantial effect on the energy balance of the wave-plasma system.

  20. Estimating evapotranspiration from a reed bed using the Bowen ratio energy balance method

    NASA Astrophysics Data System (ADS)

    Peacock, C. E.; Hess, T. M.

    2004-02-01

    An increase in demand for water for agricultural and domestic use, combined with new legislation regarding the water needs of natural habitats, has led to an increased requirement for accurate calculations of hydrological fluxes through wetlands. Evapotranspiration is one of the most important but least well understood fluxes in wetland hydrology. Research has been carried out on Stodmarsh National Nature Reserve in Kent, UK, a Ramsar site containing the largest reed beds in southern England. The objective was to quantify water loss through evapotranspiration on the site to allow more effective management of water levels and maintenance of maximum conservation potential for bird life. The Bowen ratio energy balance approach was employed, which is one of the most accurate ways of measuring evapotranspiration but has been rarely used on reed beds. These measurements were used with Penman-Monteith reference evapotranspiration in order to create crop coefficients. It was found that crop coefficients were inconsistent from day to day but were generally less than unity. The inconsistency was thought to be caused by variations in meteorological conditions: e.g. significant differences in crop coefficients were found between days with high radiation and a dry canopy, compared with days with low radiation and a wet canopy. Canopy interception of precipitation was particularly important, with crop coefficients being significantly higher on wet days, possibly due to the higher rates of evaporation of intercepted water due to the lack of stomatal resistance.

  1. Gap balancing sacrifices joint-line maintenance to improve gap symmetry: a randomized controlled trial comparing gap balancing and measured resection.

    PubMed

    Babazadeh, Sina; Dowsey, Michelle M; Stoney, James D; Choong, Peter F M

    2014-05-01

    A total knee arthroplasty can be completed using two techniques; measured resection or gap balancing. A prospective blinded randomized controlled trial was completed with 103 patients randomized to measured resection (n = 52) or gap balancing (n = 51). Primary outcome measure was femoral component rotation. Secondary outcome measures were joint-line change, gap symmetry and function and quality-of-life outcomes. Gap balancing resulted in a significantly raised joint-line compared to measured resection. Gap symmetry was significantly better using gap balancing. Functional outcomes and quality-of-life were not significantly different at 24 months. Using computer navigation, gap balancing significantly raises the joint-line in order to improve gap symmetry. This does not result in a clinical difference in function or quality of life at 24 months.

  2. A spatially distributed energy balance snowmelt model for application in mountain basins

    USGS Publications Warehouse

    Marks, D.; Domingo, J.; Susong, D.; Link, T.; Garen, D.

    1999-01-01

    Snowmelt is the principal source for soil moisture, ground-water re-charge, and stream-flow in mountainous regions of the western US, Canada, and other similar regions of the world. Information on the timing, magnitude, and contributing area of melt under variable or changing climate conditions is required for successful water and resource management. A coupled energy and mass-balance model ISNOBAL is used to simulate the development and melting of the seasonal snowcover in several mountain basins in California, Idaho, and Utah. Simulations are done over basins varying from 1 to 2500 km2, with simulation periods varying from a few days for the smallest basin, Emerald Lake watershed in California, to multiple snow seasons for the Park City area in Utah. The model is driven by topographically corrected estimates of radiation, temperature, humidity, wind, and precipitation. Simulation results in all basins closely match independently measured snow water equivalent, snow depth, or runoff during both the development and depletion of the snowcover. Spatially distributed estimates of snow deposition and melt allow us to better understand the interaction between topographic structure, climate, and moisture availability in mountain basins of the western US. Application of topographically distributed models such as this will lead to improved water resource and watershed management.Snowmelt is the principal source for soil moisture, ground-water re-charge, and stream-flow in mountainous regions of the western US, Canada, and other similar regions of the world. Information on the timing, magnitude, and contributing area of melt under variable or changing climate conditions is required for successful water and resource management. A coupled energy and mass-balance model ISNOBAL is used to simulate the development and melting of the seasonal snowcover in several mountain basins in California, Idaho, and Utah. Simulations are done over basins varying from 1 to 2500 km2, with

  3. Energy Balance Alterations Due to Cropland Conversion in a Tropical Montane Environment: Shaded Coffee to Sugarcane

    NASA Astrophysics Data System (ADS)

    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

  4. Activation energy measurements of cheese

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Temperature sweeps of cheeses using small amplitude oscillatory shear tests produced values for activation energy of flow (Ea) between 30 and 44 deg C. Soft goat cheese and Queso Fresco, which are high-moisture cheeses and do not flow when heated, exhibited Ea values between 30 and 60 kJ/mol. The ...

  5. Effects of zonal flows on correlation between energy balance and energy conservation associated with nonlinear nonviscous atmospheric dynamics in a thin rotating spherical shell

    NASA Astrophysics Data System (ADS)

    Ibragimov, Ranis N.

    2016-12-01

    The nonlinear Euler equations are used to model two-dimensional atmosphere dynamics in a thin rotating spherical shell. The energy balance is deduced on the basis of two classes of functorially independent invariant solutions associated with the model. It it shown that the energy balance is exactly the conservation law for one class of the solutions whereas the second class of invariant solutions provides and asymptotic convergence of the energy balance to the conservation law.

  6. Alterations in energy balance from an exercise intervention with ad libitum food intake.

    PubMed

    Melzer, Katarina; Renaud, Anne; Zurbuchen, Stefanie; Tschopp, Céline; Lehmann, Jan; Malatesta, Davide; Ruch, Nicole; Schutz, Yves; Kayser, Bengt; Mäder, Urs

    2016-01-01

    Better understanding is needed regarding the effects of exercise alone, without any imposed dietary regimens, as a single tool for body-weight regulation. Thus, we evaluated the effects of an 8-week increase in activity energy expenditure (AEE) on ad libitum energy intake (EI), body mass and composition in healthy participants with baseline physical activity levels (PAL) in line with international recommendations. Forty-six male adults (BMI = 19·7-29·3 kg/m(2)) participated in an intervention group, and ten (BMI = 21·0-28·4 kg/m(2)) in a control group. Anthropometric measures, cardiorespiratory fitness, EI, AEE and exercise intensity were recorded at baseline and during the 1st, 5th and 8th intervention weeks, and movement was recorded throughout. Body composition was measured at the beginning and at the end of the study, and resting energy expenditure was measured after the study. The intervention group increased PAL from 1·74 (se 0·03) to 1·93 (se 0·03) (P < 0·0001) and cardiorespiratory fitness from 41·4 (se 0·9) to 45·7 (se 1·1) ml O2/kg per min (P = 0·001) while decreasing body mass (-1·36 (se 0·2) kg; P = 0·001) through adipose tissue mass loss (ATM) (-1·61 (se 0·2) kg; P = 0·0001) compared with baseline. The control group did not show any significant changes in activity, body mass or ATM. EI was unchanged in both groups. The results indicate that in normal-weight and overweight men, increasing PAL from 1·7 to 1·9 while keeping EI ad libitum over an 8-week period produces a prolonged negative energy balance. Replication using a longer period (and/or more intense increase in PAL) is needed to investigate if and at what body composition the increase in AEE is met by an equivalent increase in EI.

  7. Perception and use of balance measures for stroke patients among physical therapists in South Korea

    PubMed Central

    Jang, Ho Young; Kim, You Lim; Lee, Suk Min

    2017-01-01

    [Purpose] The purpose of this study looked into physical therapists’ perception and use of balance measures for stroke patients. [Subjects and Methods] Three hundred eighty two physical therapists who understood the purpose of this study, agreed on their participation in this study, were treating or treated stroke patients. A Cross-sectional study based on self-administered questionnaire that had a total of 41 questions was performed in South Korea. 382 questionnaires were used for analysis. [Results] Regarding the questions about their perception and of personal measures, 287 persons (75.1%) replied that Single Leg Stance test was the most useful. According to the data analysis on their use of balance measures, Single Leg Stance Test was used by 254 persons (66.5%, the highest percentage), Functional Reach Test by 199 (52.1%). Also, stepwise multiple regression analysis was conducted. As a result, the most influential factor was physical therapists’ perception of personal measures, and their use was also influenced by their comprehensive perception of measurement and their perception of balance factors. [Conclusion] This study revealed physical therapists’ perception and use of balance measures for stroke patients and showed that their perception of balance measures for stroke patients affected their use of personal measures. PMID:28265152

  8. Effect of balanced protein energy supplementation during pregnancy on birth outcomes

    PubMed Central

    2011-01-01

    Background The nutritional status of the mother prior to and during pregnancy plays a vital role in fetal growth and development, and maternal undernourishment may lead to adverse perinatal outcomes including intrauterine growth restriction (IUGR). Several macronutrient interventions had been proposed for adequate protein and energy supplementation during pregnancy. The objective of this paper was to review the effect of balanced protein energy supplementation during pregnancy on birth outcomes. This paper is a part of a series of reviews undertaken for getting estimates of effectiveness of an intervention for input to Lives Saved Tool (LiST) model. Methods A literature search was conducted on PubMed, Cochrane Library and WHO regional data bases to identify randomized trials (RCTs) and quasi RCTs that evaluated the impact of balanced protein energy supplementation in pregnancy. Balanced protein energy supplementation was defined as nutritional supplementation during pregnancy in which proteins provided less than 25% of the total energy content. Those studies were excluded in which the main intervention was dietary advice to pregnant women for increase in protein energy intake, high protein supplementation (i.e. supplementation in which protein provides at least 25% of total energy content), isocaloric protein supplementation (where protein replaces an equal quantity of non-protein energy content), or low energy diet to pregnant women who are either overweight or who exhibit high weight gain earlier in gestation. The primary outcomes were incidence of small for gestational age (SGA) birth, mean birth weight and neonatal mortality. Quality of evidence was evaluated according to the Child Health Epidemiology Reference group (CHERG) adaptation of Grading of Recommendations Assessment, Development and Evaluation (GRADE) criteria. Results The final number of studies included in our review was eleven comprising of both RCTs and quasi-RCTs. Our meta-analysis indicates that

  9. A study on the reliability of measuring dynamic balance ability using a smartphone

    PubMed Central

    Han, Seulki; Lee, Daehee; Lee, Sangyong

    2016-01-01

    [Purpose] Evaluation of the reliability of smartphones as measuring equipment for dynamic balance ability was the goal of this study. [Subjects and Methods] Subjects were 30 healthy young students in their 20s. The first and second rounds of measurements were taken at a one-day interval to confirm test-retest reliability. The subjects stood on the footboard of the Biodex Balance System. Balance was measured using a smart phone. [Results] Acceleration rates corresponding to subjects with open eyes were 2.7 ± 2.2 (first measurement) and 3.3 ± 1.5 (second measurement), and the interclass correlation coefficient ICC (1,1) was 0.8. Acceleration rates corresponding to subjects with closed eyes were 4.1 ± 2.4 (first measurement) and 4.5 ± 1.8 (second measurement), and the ICC (1,1) was 0.9. Gyroscope rates corresponding to subjects with open eyes were 1.7 ± 1.2 (first measurement) and 2.3 ± 1.5 (second measurement), and the ICC (1,1) was 0.7. Gyroscope rates corresponding to subjects with closed eyes were 6.7 ± 2.4 (first measurement) and 6.6 ± 2.3 (second measurement), and the ICC (1,1) was 0.6. [Conclusion] The results of this study suggest that smartphones have sufficient potential as measuring equipment for dynamic balance ability. PMID:27799682

  10. Labor and energy impacts of energy-conservation measures

    SciTech Connect

    Not Available

    1980-01-01

    Three papers are presented discussing the labor and energy impacts of energy-conservation measures, namely: Generation of the Industry/Occupation Wage Matrix and Related Matters, by Carole Green; Job Shifts from Energy Conservation (Salary Distribution Effects), by Robert A. Herendeen; and Energy and Labor Implication of Improving Thermal Integrity of New Houses, by John Joseph Nangle. A separate abstract was prepared for each paper.

  11. Urinary C-peptide of insulin as a non-invasive marker of energy balance in wild orangutans.

    PubMed

    Emery Thompson, Melissa; Knott, Cheryl D

    2008-04-01

    Assessment of energetic condition is a critical tool for behavioral and reproductive ecologists. However, accurate quantification of energy intake and expenditure is labor-intensive, and it can be problematic for field scientists to obtain regular data on individual animals. C-peptide, a polypeptide segment of the proinsulin molecule that is secreted along with insulin in an equimolar relationship, can be measured in urine, and thus offers a potential means for the non-invasive assessment of energy balance in wild animals. Here, we validate C-peptide for the quantification of energetic condition, with specific application to wild orangutans (Pongo pygmaeus). We determined that application of urine to filter paper results in significantly lower C-peptide recoveries versus fresh samples. However, concentrations in filter paper samples were significantly correlated with fresh urine and were stable over various storage conditions and durations. We compared the C-peptide concentrations from wild orangutan urine samples with three independent measures of energetic condition: ketone bodies (urinalysis), caloric intake (nutritional biochemistry), and food availability (phenology). As expected, C-peptide concentrations were significantly lower in samples that tested positive for ketones in the field. Monthly average C-peptide concentrations of both male and female orangutans were significantly correlated with monthly determinations of energy intake and food availability. Therefore, we conclude that the collection and preservation of urine samples for C-peptide analysis are feasible under most field conditions and, in this species, presents a useful tool for assessing changes in energy balance.

  12. On increasing network lifetime in body area networks using global routing with energy consumption balancing.

    PubMed

    Tsouri, Gill R; Prieto, Alvaro; Argade, Nikhil

    2012-09-26

    Global routing protocols in wireless body area networks are considered. Global routing is augmented with a novel link cost function designed to balance energy consumption across the network. The result is a substantial increase in network lifetime at the expense of a marginal increase in energy per bit. Network maintenance requirements are reduced as well, since balancing energy consumption means all batteries need to be serviced at the same time and less frequently. The proposed routing protocol is evaluated using a hardware experimental setup comprising multiple nodes and an access point. The setup is used to assess network architectures, including an on-body access point and an off-body access point with varying number of antennas. Real-time experiments are conducted in indoor environments to assess performance gains. In addition, the setup is used to record channel attenuation data which are then processed in extensive computer simulations providing insight on the effect of protocol parameters on performance. Results demonstrate efficient balancing of energy consumption across all nodes, an average increase of up to 40% in network lifetime corresponding to a modest average increase of 0.4 dB in energy per bit, and a cutoff effect on required transmission power to achieve reliable connectivity.

  13. The energy balance and pressure in the solar transition zone for network and active region features

    NASA Technical Reports Server (NTRS)

    Nicolas, K. R.; Bartoe, J.-D. F.; Brueckner, G. E.; Vanhoosier, M. E.

    1979-01-01

    The electron pressure and energy balance in the solar transition zone are determined for about 125 network and active region features on the basis of high spectral and spatial resolution extreme ultraviolet spectra. Si III line intensity ratios obtained from the Naval Research Laboratory high-resolution telescope and spectrograph during a rocket flight are used as diagnostics of electron density and pressure for solar features near 3.5 x 10 to the 4th K. Observed ratios are compared with the calculated dependence of the 1301 A/1312 A and 1301 A/1296 A line intensity ratios on electron density, temperature and pressure. Electron densities ranging from 2 x 10 to the 10th/cu cm to 10 to the 12th/cu cm and active region pressures from 3 x 10 to the 15th to 10 to the 16th/cu cm K are obtained. Energy balance calculations reveal the balance of the divergence of the conductive flux and turbulent energy dissipation by radiative energy losses in a plane-parallel homogeneous transition zone (fill factor of 1), and an energy source requirement for a cylindrical zone geometry (fill factor less than 0.04).

  14. Nicotine induces negative energy balance through hypothalamic AMP-activated protein kinase.

    PubMed

    Martínez de Morentin, Pablo B; Whittle, Andrew J; Fernø, Johan; Nogueiras, Rubén; Diéguez, Carlos; Vidal-Puig, Antonio; López, Miguel

    2012-04-01

    Smokers around the world commonly report increased body weight after smoking cessation as a major factor that interferes with their attempts to quit. Numerous controlled studies in both humans and rodents have reported that nicotine exerts a marked anorectic action. The effects of nicotine on energy homeostasis have been mostly pinpointed in the central nervous system, but the molecular mechanisms controlling its action are still not fully understood. The aim of this study was to investigate the effect of nicotine on hypothalamic AMP-activated protein kinase (AMPK) and its effect on energy balance. Here we demonstrate that nicotine-induced weight loss is associated with inactivation of hypothalamic AMPK, decreased orexigenic signaling in the hypothalamus, increased energy expenditure as a result of increased locomotor activity, increased thermogenesis in brown adipose tissue (BAT), and alterations in fuel substrate utilization. Conversely, nicotine withdrawal or genetic activation of hypothalamic AMPK in the ventromedial nucleus of the hypothalamus reversed nicotine-induced negative energy balance. Overall these data demonstrate that the effects of nicotine on energy balance involve specific modulation of the hypothalamic AMPK-BAT axis. These targets may be relevant for the development of new therapies for human obesity.

  15. Preliminary measurements on heat balance in pneumatic tires

    NASA Technical Reports Server (NTRS)

    Nybakken, G. H.; Collart, D. Y.; Staples, R. J.; Lackey, J. I.; Clark, S. K.; Dodge, R. N.

    1973-01-01

    A variety of tests was undertaken to determine the nature of heat generation associated with a pneumatic tire operating under various conditions. Tests were conducted to determine the magnitude and distribution of internally generated heat caused by hysteresis in the rubber and ply fabric in an automobile tire operating under conditions of load, pressure, and velocity representative of normal operating conditions. These included tests at various yaw angles and tests with braking applied. In other tests, temperature sensors were mounted on a road to measure the effect of a tire rolling over and an attempt was made to deduce the magnitude and nature of interfacial friction from the resulting information. In addition, tests were performed using the scratch plate technique to determine the nature of the motion between the tire and road. Finally, a model tire was tested on a roadwheel, the surface covering which could be changed, and an optical pyrometer was used to measure rubber surface temperatures.

  16. Non-closure of the surface energy balance explained by phase difference between vertical velocity and scalars of large atmospheric eddies

    NASA Astrophysics Data System (ADS)

    Gao, Zhongming; Liu, Heping; Katul, Gabriel G.; Foken, Thomas

    2017-03-01

    It is now accepted that large-scale turbulent eddies impact the widely reported non-closure of the surface energy balance when latent and sensible heat fluxes are measured using the eddy covariance method in the atmospheric surface layer (ASL). However, a mechanistic link between large eddies and non-closure of the surface energy balance remains a subject of inquiry. Here, measured 10 Hz time series of vertical velocity, air temperature, and water vapor density collected in the ASL are analyzed for conditions where entrainment and/or horizontal advection separately predominate. The series are decomposed into small- and large- eddies based on a frequency cutoff and their contributions to turbulent fluxes are analyzed. Phase difference between vertical velocity and water vapor density associated with large eddies reduces latent heat fluxes, especially in conditions where advection prevails. Enlarged phase difference of large eddies linked to entrainment or advection occurrence leads to increased residuals of the surface energy balance.

  17. Application of the two-source energy balance model to partition evapotranspiration in an arid wine vineyard

    NASA Astrophysics Data System (ADS)

    Kool, Dilia; Kustas, William P.; Agam, Nurit

    2016-04-01

    The partitioning of evapotranspiration (ET) into transpiration (T), a productive water use, and soil water evaporation (E), which is generally considered a water loss, is highly relevant to agriculture in the light of increasing desertification and water scarcity. This task is challenged by the complexity of soil and plant interactions, coupled with changes in atmospheric and soil water content conditions. Many of the processes controlling water/energy exchange are not adequately modeled. The two-source energy balance model (TSEB) was evaluated and adapted for independent E and T estimations in an isolated drip-irrigated wine vineyard in the arid Negev desert. The TSEB model estimates ET by computing vegetation and soil energy fluxes using remotely sensed composite surface temperature, local weather data (solar radiation, air temperature and humidity, and wind speed), and vegetation metrics (row spacing, canopy height and width, and leaf area). The soil and vegetation energy fluxes are computed numerically using a system of temperature gradient and resistance equations; where soil and canopy temperatures are derived from the composite surface temperature. For estimation of ET, the TSEB model has been shown to perform well for various agricultural crops under a wide range of environmental conditions, but validation of T and E fluxes is limited to one study in a well-watered cotton crop. Extending the TSEB approach to water-limited vineyards demands careful consideration regarding how the complex canopy structure of vineyards will influence the accuracy of the partitioning between E and T. Data for evaluation of the TSEB model were collected over a season (bud break till harvest). Composite, canopy, and soil surface temperatures were measured using infrared thermometers. The composite vegetation and soil surface energy fluxes were assessed using independent measurements of net radiation, and soil, sensible and latent heat flux. The below canopy energy balance was

  18. Evapotranspiration using a satellite-based surface energy balance with standardized ground control

    NASA Astrophysics Data System (ADS)

    Trezza, Ricardo

    This study evaluated the potential of using the S&barbelow;urface E&barbelow;nergy Ḇalance A&barbelow;lgorithm for Ḻand (SEBAL) as a means for estimating evapotranspiration (ET) for local and regional scales in Southern Idaho. The original SEBAL model was refined during this study to provide better estimation of ET in agricultural areas and to make more reliable estimates of ET from other surfaces as well, including mountainous terrain. The modified version of SEBAL used in this study, termed as SEBALID (ID stands for Idaho) includes standardization of the two SEBAL "anchor" pixels, the use of a water balance model to track top soil moisture, adaptation of components of SEBAL for better prediction of the surface energy balance in mountains and sloping terrain, and use of the ratio between actual ET and alfalfa reference evapotranspiration (ET r) as a means for obtaining the temporal integration of instantaneous ET to daily and seasonal values. Validation of the SEBALID model at a local scale was performed by comparing lysimeter ET measurements from the USDA-ARS facility at Kimberly, Idaho, with ET predictions by SEBAL using Landsat 5 TM imagery. Comparison of measured and predicted ET values was challenging due to the resolution of the Landsat thermal band (120m x 120m) and the relatively small size of the lysimeter fields. In the cases where thermal information was adequate, SEBALID predictions were close to the measured values of ET in the lysimeters. Application of SEBALID at a regional scale was performed using Landsat 7 ETM+ and Landsat 5 TM imagery for the Eastern Snake Plain Aquifer (ESPA) region in Idaho during 2000. The results indicated that SEBALID performed well for predicting daily and seasonal ET for agricultural areas. Some unreasonable results were obtained for desert and basalt areas, due to uncertainties of the prediction of surface parameters. In mountains, even though validation of results was not possible, the values of ET obtained

  19. Effects of 3-nitrooxypropanol on methane emission, digestion, and energy and nitrogen balance of lactating dairy cows.

    PubMed

    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

  20. Influence of intense physical activity on energy balance and body fatness.

    PubMed

    Tremblay, A; Doucet, E

    1999-02-01

    The reduced contribution of physical activity to daily energy expenditure and the accessibility to high-fat foods have put an excessive burden on energy balance, resulting in an increase in the prevalence of obesity throughout the world. In this context, fat gain can be seen as a natural adaptation to deal with a fattening lifestyle, since the hormonal adaptations that accompany fat gain favour the readjustment of energy expenditure to energy intake. Intense physical activity would also seem to facilitate the regulation of energy balance, since it increases the energy cost of exercise, increases post-exercise energy expenditure and the potential of skeletal muscles to utilize lipids, and also favours a decrease in post-exercise intake. Moreover, the effects of intense exercise seem to be mediated by an activation of sympathetic nervous system activity that seems to be specific to skeletal muscle. It is also important to manipulate macronutrient composition in order to reduce fat intake, because unhealthy food habits can favour overfeeding and thus overcome the energy deficit caused by regular physical activity. Under free-living conditions, the combination of vigorous activity and healthy food practices can amount to a substantial weight loss which is comparable with that of other non-surgical approaches to treat obesity.

  1. EuropeaN Energy balance Research to prevent excessive weight Gain among Youth (ENERGY) project: Design and methodology of the ENERGY cross-sectional survey

    PubMed Central

    2011-01-01

    Background Obesity treatment is by large ineffective long term, and more emphasis on the prevention of excessive weight gain in childhood and adolescence is warranted. To inform energy balance related behaviour (EBRB) change interventions, insight in the potential personal, family and school environmental correlates of these behaviours is needed. Studies on such multilevel correlates of EBRB among schoolchildren in Europe are lacking. The ENERGY survey aims to (1) provide up-to-date prevalence rates of measured overweight, obesity, self-reported engagement in EBRBs, and objective accelerometer-based assessment of physical activity and sedentary behaviour and blood-sample biomarkers of metabolic function in countries in different regions of Europe, (2) to identify personal, family and school environmental correlates of these EBRBs. This paper describes the design, methodology and protocol of the survey. Method/Design A school-based cross-sectional survey was carried out in 2010 in seven different European countries; Belgium, Greece, Hungary, the Netherlands, Norway, Slovenia, and Spain. The survey included measurements of anthropometrics, child, parent and school-staff questionnaires, and school observations to measure and assess outcomes (i.e. height, weight, and waist circumference), EBRBs and potential personal, family and school environmental correlates of these behaviours including the social-cultural, physical, political, and economic environmental factors. In addition, a selection of countries conducted accelerometer measurements to objectively assess physical activity and sedentary behaviour, and collected blood samples to assess several biomarkers of metabolic function. Discussion The ENERGY survey is a comprehensive cross-sectional study measuring anthropometrics and biomarkers as well as assessing a range of EBRBs and their potential correlates at the personal, family and school level, among 10-12 year old children in seven European countries. This study

  2. Assessing the controls of the snow energy balance and water available for runoff in a rain-on-snow environment

    NASA Astrophysics Data System (ADS)

    Mazurkiewicz, Adam B.; Callery, David G.; McDonnell, Jeffrey J.

    2008-06-01

    SummaryRain-on-snow (ROS) melt production and its contribution to water available for runoff is poorly understood. In the Pacific Northwest (PNW) of the USA, ROS drives many runoff events with turbulent energy exchanges dominating the snow energy balance (EB). While previous experimental work in the PNW (most notably the H.J. Andrews Experimental Forest (HJA)) has quantified these energy balance components for a handful of ROS events, little is known about the EB components of snowmelt at HJA on an annual basis and how the relative importance of each component changes with different time periods of analysis. Beyond the few measured events at HJA and elsewhere in the PNW, there is still a lack of understanding of the dominant components of the EB during high-frequency ROS events and how much annual snowmelt is produced during ROS events. A physically based snow energy balance model (SNOBAL) was applied to data from three climate stations in the HJA to address these questions. Measurements of all required forcing data except incoming longwave radiation were made at each site. We employ the largest ROS dataset ever amassed with SNOBAL to use the model as a learning tool to characterize the snowmelt regime in the HJA. The results show that radiation dominated the melt energy balance over the period 1996-2003 while net turbulent energy exchanges were much lower than expected. Annual variability in EB components reflected duration of snowpack (snow covered period) - where later season snowpack resulted in higher radiation as percentage of the total EB. Radiation was the largest contributor to melt during ROS. These results question the general perception of turbulent energy exchange dominance of ROS and seasonal melt in the PNW. Overall, melt from ROS events was a small percentage of annual melt - for the period 1996-2003 snow season, 80-90% of snowmelt comes from non-ROS days. These results prove the highly variable spatial and temporal controls on the snowmelt regime

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

    PubMed

    Berryman, Claire E; Sepowitz, John J; McClung, Holly L; Lieberman, Harris R; Farina, Emily K; McClung, James P; Ferrando, Arny A; Pasiakos, Stefan M

    2017-04-06

    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 d (POST) of severe negative energy balance during military training in 63 male US Marines (mean±SD, 25±3 y, 84±9 kg). After POST measures were collected, volunteers were randomized to receive higher-protein (HIGH: 1103 kcal/d, 133 g protein/d), moderate protein (MOD: 974 kcal/d, 84 g protein/d), or carbohydrate-based low protein control (CON: 1042 kcal/d, 7 g protein/d) supplements, in addition to a self-selected, ad libitum diet, for the 27 d 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/d) were lower and proteolysis (1.1±1.9 g protein/kg/d) was higher compared to PRE (P<0.05). Self-selected, ad libitum dietary intake during REFED was similar between groups (3507 ± 730 kcal/d, 2.0±0.5 g protein/kg/d). However, diets differed by protein intake due to supplementation (CON: 2.0±0.4, MOD: 3.2±0.7, HIGH: 3.5±0.7 g/kg/d; P<0.05) but not total energy (4498±725 kcal/d). All volunteers, independent of group assignment, achieved positive net protein balance (0.4±1.0 g protein/kg/d) and gained TBM (5.9±1.7 kg, 7.8%) and FFM (3.6±1.8 kg, 5.7%) POST-REFED compared to POST (P<0.05). Supplementing ad libitum, energy-adequate, higher-protein diets with additional protein may not be necessary to restore FFM after short-term severe negative energy balance.

  4. Advances in the two-source energy balance model: Partioning of evaporation and transpiration for row crops for cotton

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Accurate partitioning of the evaporation (E) and transpiration (T) components of evapotranspiration (ET) in remote sensing models is important for evaluating strategies aimed at increasing crop water productivity. The two-source energy balance (TSEB) model solves the energy balance of the soil-plant...

  5. Advances in the two-source energy balance model:Partioning of evaporation and transpiration for row crops

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Accurate partitioning of the evaporation (E) and transpiration (T) components of evapotranspiration (ET) in remote sensing models is important for evaluating strategies aimed at increasing crop water productivity. The two-source energy balance (TSEB) model solves the energy balance of the soil-plant...

  6. Impact of Sleep and Circadian Disruption on Energy Balance and Diabetes: A Summary of Workshop Discussions

    PubMed Central

    Arble, Deanna M.; Bass, Joseph; Behn, Cecilia Diniz; Butler, Matthew P.; Challet, Etienne; Czeisler, Charles; Depner, Christopher M.; Elmquist, Joel; Franken, Paul; Grandner, Michael A.; Hanlon, Erin C.; Keene, Alex C.; Joyner, Michael J.; Karatsoreos, Ilia; Kern, Philip A.; Klein, Samuel; Morris, Christopher J.; Pack, Allan I.; Panda, Satchidananda; Ptacek, Louis J.; Punjabi, Naresh M.; Sassone-Corsi, Paolo; Scheer, Frank A.; Saxena, Richa; Seaquest, Elizabeth R.; Thimgan, Matthew S.; Van Cauter, Eve; Wright, Kenneth P.

    2015-01-01

    A workshop was held at the National Institute for Diabetes and Digestive and Kidney Diseases with a focus on the impact of sleep and circadian disruption on energy balance and diabetes. The workshop identified a number of key principles for research in this area and a number of specific opportunities. Studies in this area would be facilitated by active collaboration between investigators in sleep/circadian research and investigators in metabolism/diabetes. There is a need to translate the elegant findings from basic research into improving the metabolic health of the American public. There is also a need for investigators studying the impact of sleep/circadian disruption in humans to move beyond measurements of insulin and glucose and conduct more in-depth phenotyping. There is also a need for the assessments of sleep and circadian rhythms as well as assessments for sleep-disordered breathing to be incorporated into all ongoing cohort studies related to diabetes risk. Studies in humans need to complement the elegant short-term laboratory-based human studies of simulated short sleep and shift work etc. with studies in subjects in the general population with these disorders. It is conceivable that chronic adaptations occur, and if so, the mechanisms by which they occur needs to be identified and understood. Particular areas of opportunity that are ready for translation are studies to address whether CPAP treatment of patients with pre-diabetes and obstructive sleep apnea (OSA) prevents or delays the onset of diabetes and whether temporal restricted feeding has the same impact on obesity rates in humans as it does in mice. Citation: Arble DM, Bass J, Behn CD, Butler MP, Challet E, Czeisler C, Depner CM, Elmquist J, Franken P, Grandner MA, Hanlon EC, Keene AC, Joyner MJ, Karatsoreos I, Kern PA, Klein S, Morris CJ, Pack AI, Panda S, Ptacek LJ, Punjabi NM, Sassone-Corsi P, Scheer FA, Saxena R, Seaquest ER, Thimgan MS, Van Cauter E, Wright KP. Impact of sleep and

  7. Water flow and energy balance for a tropical dry semideciduous forest

    NASA Astrophysics Data System (ADS)

    Andrade, J. L.; Garruña-Hernandez, R.; Leon-Palomo, M.; Us-Santamaria, R.; Sima, J. L.

    2013-05-01

    Tropical forests cool down locally because increase water evaporation from the soil to the atmosphere, reduce albedo and help forming clouds that reflect solar radiation back to the atmosphere; this, aligned to the carbon catchment, increase forests value. We will present an estimation of the sap flow and energy balance for the tropical dry semideciduous forest at Kiuic, Yucatan, Mexico during a year. We use a meteorological tower equipped with a rain gauge, temperature and relative humidity, heat flow plates, thermocouples and volumetric soil water content. We recorded net radiation and soil heat flux and estimated sensible heat and latent heat. Besides, we estimated latent heat by measuring sap flow directly in tres using disispation constant heat probes during the rainy season. Results show the influence of the seasonality on net radiation, air temperatura and vapor pressure deficit, because during the dry season his variables were higher and with more duation than during the rainy and early dry season. Sap flow was different for trees belonging to the family Fabaceae compared to trees from other families.

  8. Physical activity, sedentary behaviour and energy balance in the preschool child: opportunities for early obesity prevention.

    PubMed

    Reilly, John J

    2008-08-01

    Prevalence of obesity in preschool children has increased dramatically in recent years. The preschool years (age 3-6 years) have been regarded as critical for the programming of energy balance, via the concept of early 'adiposity rebound'. Children who undergo early adiposity rebound are at increased risk of later obesity. Recent evidence suggests that associations between timing of adiposity rebound and later obesity may not reflect programming, but might denote that 'obesogenic' growth trajectories are often established by the preschool period. Studies of objectively-measured physical activity and sedentary behaviour in preschool children show that levels of physical activity are typically low and sedentary behaviour high. The review of evidence presented here is supportive of the hypothesis that physical activity is protective against obesity in the preschool period, and that sedentary behaviour, particularly television viewing, is obesogenic. Definitive evidence on dose-response relationships between physical activity, sedentary behaviour and obesity remain unclear. Dose-response evidence could be obtained fairly readily by intervention and longitudinal observational studies that use accelerometry in preschool children. The generalisability of much of the evidence base is limited and there is a need for research on the influence of physical activity and sedentary behaviour in the preschool years in the aetiology of obesity in the developing world.

  9. Including the effects of debris cover in a distributed glacier energy balance model (Invited)

    NASA Astrophysics Data System (ADS)

    Pellicciotti, F.; Reid, T.; Carenzo, M.; Brock, B. W.

    2010-12-01

    Distributed models of glacier energy balance, which make use of digital elevation models and extensive spatial data on local meteorology, have become very useful tools for predicting glacial ablation and runoff in recent years. They generally function by running a one-dimensional energy balance model at every point on a grid on the glacier surface - for each point in the grid the ablation is calculated based on the balance of heat fluxes at the ice-air boundary. However, one key component has been missing from distributed models to date, namely the effects of debris cover. Many glacier ablation zones are mantled in near-continuous blankets of rock debris, and debris-covered glaciers are important drivers of the water cycle in the European Alps, Andes and Himalayas. Moreover, debris covers have been seen to expand in recent years, so it is essential to assess exactly how the presence of debris may affect a glacier’s surface energy balance and potential responses to climate changes. The effects of a debris cover are complicated by the varying surface roughness, albedo and thermal properties of the debris in question, but generally a debris cover reduces glacier melt rate by insulating the glacier surface from direct solar radiation. Even on glaciers where the debris cover is not continuous, isolated patches of debris caused by rockfalls can affect the glacier evolution by introducing differential ablation across the glacier surface, thus creating ice-cored moraines that may persist after ‘clean’ parts of the glacier have wasted away. This paper presents the results of incorporating a one-dimensional ‘debris energy balance model’ called DEB-Model (Reid and Brock 2010) into a distributed melt model for Haut Glacier d’Arolla, Switzerland. DEB-Model numerically estimates debris surface temperature by considering the balance of heat fluxes at the air-debris interface, then calculates heat conduction through the debris in order to estimate melt rates at the

  10. Monitoring Evaporation/Transpiration in a Vineyard from Two-Source Energy Balance and Radiometric Temperatures

    NASA Astrophysics Data System (ADS)

    Sánchez, Juan Manuel; Doña, Carolina; Cuxart, Joan; Caselles, Vicente; Niclòs, Raquel

    2014-05-01

    Water management and understanding of irrigation efficiency could be significantly improved if the components of evapotranspiration (ET) in row-crop systems (plants and soil interrows) could be quantified separately. This evaporation/transpiration (E/T) partition, and its daily and seasonal evolution, depends on a variety of biophysical and environmental factors. In this work we present an operational method to provide continuous E/T results avoiding soil or canopy disturbance. This technique is based on the combination of the surface-atmosphere energy exchange modeling together with an accurate remote thermal characterization of the crop elements. An experiment was carried out in a row-crop vineyard in Mallorca, Spain, from June 2012 to May 2013. A set of 6 thermal-infrared radiometers (IRTs) were mounted in a mast placed in the middle of a vineyard N-S row. Two IRTs pointed to the soil between rows and other two pointed to the plants from a frontal view, measuring both east and west sides of the row. A fifth IRT pointed upward to collect the downwelling sky radiance and the remaining IRT was mounted at 4.5-m height over the canopy measuring the composed soil-canopy temperature. Measurements of the four components of the net radiation over the canopy and soil heat fluxes, as well as air temperature, humidity, wind speed, and soil moisture, were collected and stored in 15-min averages. A two-source energy balance approach was applied to the vineyard from its appropriate thermal characterization. Total and separate soil/canopy components of net radiation, soil, sensible and latent heat fluxes were obtained every 15 minutes and averaged at hourly and daily scales. Comparison between observed and modeled values of available surface energy showed relative errors below 15%. An analysis of the partition E/T was conducted along the vineyard growing season and the different phenological stages. In this experiment, interrow soil evaporation reached as much as 1/3 of the

  11. Water, ice, and meteorological measurements at South Cascade glacier, Washington, balance year 2003

    USGS Publications Warehouse

    Bidlake, William R.; Josberger, Edward G.; Savoca, Mark E.

    2005-01-01

    Winter snow accumulation and summer snow and ice ablation were measured at South Cascade Glacier, Washington, to estimate glacier mass-balance quantities for balance year 2003. The 2003 glacier-average maximum winter snow balance was 2.66 meters water equivalent, which was about equal to the average of such balances for the glacier since balance year 1959. The 2003 glacier summer balance (-4.76 meters water equivalent) was the most negative reported for the glacier, and the 2003 net balance (-2.10 meters water equivalent), was the second-most negative reported. The glacier 2003 annual (water year) balance was -1.89 meters water equivalent. The area of the glacier near the end of the balance year was 1.89 square kilometers, a decrease of 0.03 square kilometer from the previous year. The equilibrium-line altitude was higher than any part of the glacier; however, because snow remained along part of one side of the upper glacier, the accumulation-area ratio was 0.07. During September 13, 2002-September 13, 2003, the glacier terminus retreated at a rate of about 15 meters per year. Average speed of surface ice, computed using a series of vertical aerial photographs dating back to 2001, ranged from 2.2 to 21.8 meters per year. Runoff from the subbasin containing the glacier and from an adjacent non-glacierized basin was gaged during part of water year 2003. Air temperature, precipitation, atmospheric water-vapor pressure, wind speed, and incoming solar radiation were measured at selected locations on and near the glacier. Summer 2003 at the glacier was among the warmest for which data are available.

  12. Relationship between balance and physical activity measured by an activity monitor in elderly COPD patients

    PubMed Central

    Iwakura, Masahiro; Okura, Kazuki; Shibata, Kazuyuki; Kawagoshi, Atsuyoshi; Sugawara, Keiyu; Takahashi, Hitomi; Shioya, Takanobu

    2016-01-01

    Background Little is known regarding the relationship between balance impairments and physical activity in COPD. There has been no study investigating the relationship between balance and objectively measured physical activity. Here we investigated the association between balance and physical activity measured by an activity monitor in elderly COPD patients. Materials and methods Twenty-two outpatients with COPD (mean age, 72±7 years; forced expiratory volume in 1 second, 53%±21% predicted) and 13 age-matched healthy control subjects (mean age, 72±6 years) participated in the study. We assessed all 35 subjects’ balance (one-leg standing test [OLST] times, Short Physical Performance Battery total scores, standing balance test scores, 4 m gait speed, and five-times sit-to-stand test [5STST]) and physical activity (daily steps and time spent in moderate-to-vigorous physical activity per day [MV-PA]). Possible confounders were assessed in the COPD group. The between-group differences in balance test scores and physical activity were analyzed. A correlation analysis and multivariate regression analysis were conducted in the COPD group. Results The COPD patients exhibited significant reductions in OLST times (P=0.033), Short Physical Performance Battery scores (P=0.013), 4 m gait speed (P<0.001), five-times sit-to-stand times (P=0.002), daily steps (P=0.003), and MV-PA (P=0.022) compared to the controls; the exception was the standing balance test scores. The correlation and multivariate regression analyses revealed significant independent associations between OLST times and daily steps (P<0.001) and between OLST times and MV-PA (P=0.014) in the COPD group after adjusting for possible confounding factors. Conclusion Impairments in balance and reductions in physical activity were observed in the COPD group. Deficits in balance are independently associated with physical inactivity. PMID:27445470

  13. Energy and carbon balances with phenology over the larch forests on the permafrost in northern Mongolia

    NASA Astrophysics Data System (ADS)

    Miyazaki, S.; Ishikawa, M.; Nachin, B.; Sodov, D.; Yamkhin, J.

    2012-12-01

    To clarify the heat, water carbon exchange process and dynamics by comprehensive approach, we've carried out the long term monitoring of the energy and carbon balances, the hydro-climatic, the phonological camera monitoring and sap flow measurement at the 25-m height tower and larch forest around the tower in the Udleg (48 15'43.7" N, 106 50'56.6"E, altitude: 1264m) in permafrost area of northern Mongolia since 2010. The annual range of air temperature and annual mean air temperature were about 60 degree C and -1 degree C, respectively. The annual precipitation was about 250 mm with about 90% of it from May to September. According to the image analysis of in situ camera and PAR albedo data, we clarified the seasonal variation of surface condition and phenology of larch forest. From January to March, November and December, there was continuous snow cover on the surface when the PAR albedo was about 0.15 to 0.2. In late May the leaf of larch emerged and attained the mature growth in July, and then the leaf senescence occurred in mid September. The PAR albedo shows abrupt decrease in late May and abrupt increase in mid September that coincides with the leaf emergence and senescence. The soil moisture at 10 cm depth was less than 10% before April, then it gradually increase in May to 20% in August, after that it decreases to less than 10% from October. The temporal variation of soil moisture matched to temporal variation of rainfall. The soil temperature below 3m was about -0.2 degree C in all year round that suggests that there is the permafrost. In late May the latent heat flux start to increase with soil moisture and become dominant component of energy fluxes from mid June to early September when the carbon uptake was active. From mid September to early June, the sensible heat flux was dominant component of energy fluxes when the surface was carbon source. We found that the close relationship between phenology (leaf emergence, growth and senescence) of larch trees

  14. Distributed energy-balance modeling of snow-cover evolution and melt in rugged terrain: Tobacco Root Mountains, Montana, USA

    NASA Astrophysics Data System (ADS)

    Letsinger, Sally L.; Olyphant, Greg A.

    2007-03-01

    SummaryA distributed energy-balance model was developed for simulating snowpack evolution and melt in rugged terrain. The model, which was applied to a 43-km 2 watershed in the Tobacco Root Mountains, Montana, USA, used measured ambient data from nearby weather stations to drive energy-balance calculations and to constrain the model of Liston and Sturm [Liston, G.E., Sturm, M., 1998. A snow-transport model for complex terrain. Journal of Glaciology 44 (148), 498-516] for calculating the initial snowpack thickness. Simulated initial snow-water equivalent ranged between 1 cm and 385 cm w.e. (water equivalent) with high values concentrated on east-facing slopes below tall summits. An interpreted satellite image of the snowcover distribution on May 6, 1998, closely matched the simulated distribution with the greatest discrepancy occurring in the floor of the main trunk valley. Model simulations indicated that snowmelt commenced early in the melt season, but rapid meltout of snow cover did not occur until after the average energy balance of the entire watershed became positive about 45 days into the melt season. Meltout was fastest in the lower part of the watershed where warmer temperatures and tree cover enhanced the energy income of the underlying snow. An interpreted satellite image of the snowcover distribution on July 9, 1998 compared favorably with the simulated distribution, and melt curves for modeled canopy-covered cells mimicked the trends measured at nearby snow pillow stations. By the end of the simulation period (August 3), 28% of the watershed remained snow covered, most of which was concentrated in the highest parts of the watershed where initially thick accumulations had been shaded by surrounding summits. The results of this study provide further demonstration of the critical role that topography plays in the timing and magnitude of snowmelt from high mountain watersheds.

  15. Distributed energy-balance modeling of snow-cover evolution and melt in rugged terrain: Tobacco Root Mountains, Montana, USA

    USGS Publications Warehouse

    Letsinger, S.L.; Olyphant, G.A.

    2007-01-01

    A distributed energy-balance model was developed for simulating snowpack evolution and melt in rugged terrain. The model, which was applied to a 43-km2 watershed in the Tobacco Root Mountains, Montana, USA, used measured ambient data from nearby weather stations to drive energy-balance calculations and to constrain the model of Liston and Sturm [Liston, G.E., Sturm, M., 1998. A snow-transport model for complex terrain. Journal of Glaciology 44 (148), 498-516] for calculating the initial snowpack thickness. Simulated initial snow-water equivalent ranged between 1 cm and 385 cm w.e. (water equivalent) with high values concentrated on east-facing slopes below tall summits. An interpreted satellite image of the snowcover distribution on May 6, 1998, closely matched the simulated distribution with the greatest discrepancy occurring in the floor of the main trunk valley. Model simulations indicated that snowmelt commenced early in the melt season, but rapid meltout of snow cover did not occur until after the average energy balance of the entire watershed became positive about 45 days into the melt season. Meltout was fastest in the lower part of the watershed where warmer temperatures and tree cover enhanced the energy income of the underlying snow. An interpreted satellite image of the snowcover distribution on July 9, 1998 compared favorably with the simulated distribution, and melt curves for modeled canopy-covered cells mimicked the trends measured at nearby snow pillow stations. By the end of the simulation period (August 3), 28% of the watershed remained snow covered, most of which was concentrated in the highest parts of the watershed where initially thick accumulations had been shaded by surrounding summits. The results of this study provide further demonstration of the critical role that topography plays in the timing and magnitude of snowmelt from high mountain watersheds. ?? 2006 Elsevier B.V. All rights reserved.

  16. Genetics of grass dry matter intake, energy balance, and digestibility in grazing irish dairy cows.

    PubMed

    Berry, D P; Horan, B; O'Donovan, M; Buckley, F; Kennedy, E; McEvoy, M; Dillon, P

    2007-10-01

    The objective of this study was to estimate genetic parameters for grass dry matter intake (DMI), energy balance (EB), and cow internal digestibility (IDG) in grazing Holstein-Friesian dairy cows. Grass DMI was estimated up to 4 times per lactation on 1,588 lactations from 755 cows on 2 research farms in southern Ireland. Simultaneously measured milk production and BW records were used to calculate EB. Cow IDG, measured as the ratio of feed and fecal concentrations of the natural odd carbon-chain n-alkane pentatriacontane, was available on 583 lactations from 238 cows. Random regression and multitrait animal models were used to estimate residual, additive genetic and permanent environmental (co)variances across lactations. Results were similar for both models. Heritability for DMI, EB, and IDG across lactation varied from 0.10 [8 days in milk (DIM)] to 0.30 (169 DIM), from 0.06 (29 DIM) to 0.29 (305 DIM), and from 0.08 (50 DIM) to 0.45 (305 DIM), respectively, when estimated using the random regression model. Genetic correlations within each trait tended to decrease as the interval between periods compared increased for DMI and EB, whereas the correlations with IDG in early lactation were weakest when measured midlactation. The lowest correlation between any 2 periods was 0.10, -0.36, and -0.04 for DMI, EB, and IDG, respectively, suggesting the effect of different genes at different stages of lactations. Eigenvalues and associated eigenfunctions of the additive genetic covariance matrix revealed considerable genetic variation among animals in the shape of the lactation profiles for DMI, EB, and IDG. Genetic parameters presented are the first estimates from dairy cows fed predominantly grazed grass and imply that genetic improvement in DMI, EB, and IDG in Holstein-Friesian cows fed predominantly grazed grass is possible.

  17. The effect of cloud type on Earth's energy balance - Global analysis

    NASA Technical Reports Server (NTRS)

    Hartmann, Dennis L.; Ockert-Bell, Maureen E.; Michelsen, Marc L.

    1992-01-01

    The role of fractional area coverage by cloud types in the energy balance of the earth is investigated through joint use of International Satellite Cloud Climatology Project (ISCCP) C1 cloud data and Earth Radiation Budget Experiment (ERBE) broadband energy flux data for the one-year period March 1985 through February 1986. Multiple linear regression is used to relate the radiation budget data to the cloud data. Comparing cloud forcing estimates obtained from the ISCCP-ERBE regression with those derived from the ERBE scene identification shows generally good agreement except over snow, in tropical convective regions, and in regions that are either nearly cloudless or always overcast. It is suggested that a substantial fraction of the disagreement in longwave cloud forcing in tropical convective regions is associated with the fact that the ERBE scene identification does not take into account variations in upper-tropospheric water vapor. On a global average basis, low clouds make the largest contribution to the net energy balance of the Earth, because they cover such a large area and because their albedo effect dominates their effect on emitted thermal radiation. High, optically thick clouds can also very effectively reduce the energy balance, however, because their very high albedos overcome their low emission temperatures.

  18. Effects of fatty acid supplements on milk yield and energy balance of lactating dairy cows.

    PubMed

    Harvatine, K J; Allen, M S

    2006-03-01

    Saturated and unsaturated fatty acid supplements (FS) were evaluated for effects on yield of milk and milk components, concentration of milk components including milk fatty acid profile, and energy balance. Eight ruminally and duodenally cannulated cows and 8 noncannulated cows were used in a replicated 4 x 4 Latin square design experiment with 21-d periods. Treatments were control and a linear substitution of 2.5% fatty acids from saturated FS (SAT; prilled, hydrogenated free fatty acids) for partially unsaturated FS (UNS; calcium soaps of long-chain fatty acids). The SAT treatment did not change milk fat concentration, but UNS linearly decreased milk fat in cannulated cows and tended to decrease milk fat in noncannulated cows compared with control. Milk fat depression with UNS corresponded to increased concentrations of trans-10, cis-12 conjugated linoleic acid and trans C18:1 fatty acids in milk. Milk fat profile was similar for SAT and control, but UNS decreased concentration of short- and medium-chain FA. Digestible energy intake tended to decrease linearly with increasing unsaturated FS in cannulated and noncannulated cows. Increasing unsaturated FS linearly increased empty body weight and net energy gain in cannulated cows, whereas increasing saturated FS linearly increased plasma insulin. Efficiency of conversion of digestible energy to milk tended to decrease linearly with increasing unsaturated FS for cannulated cows only. Addition of SAT provided little benefit to production and energy balance, whereas UNS decreased energy intake and milk energy yield.

  19. Comparison of evapotranspiration estimates from the Surface Energy Balance Algorithm (SEBAL) and flux tower data, middle Rio Grande Basin

    NASA Astrophysics Data System (ADS)

    Xie, H.; Hendrickx, J.; Kurc, S.; Small, E.

    2002-12-01

    Evapotranspiration (ET) is one of the most important components of the water balance, but also one of the most difficult to measure. Field techniques such as soil water balances and Bowen ratio or eddy covariance techniques are local, ranging from point to field scale. SEBAL (Surface Energy Balance Algorithm for Land) is an image-processing model that calculates ET and other energy exchanges at the earth's surface. SEBAL uses satellite image data (TM/ETM+, MODIS, AVHRR, ASTER, and so on) measuring visible, near-infrared, and thermal infrared radiation. SEBAL algorithms predict a complete radiation and energy balance for the surface along with fluxes of sensible heat and aerodynamic surface roughness (Bastiaanssen et al, 1998; and Allen et al. 2001). We are constructing a GIS based database that includes spatially-distributed estimates of ET from remote-sensed data at a resolution of about 30 m. The SEBAL code will be optimized for this region via comparison of surface based observations of ET, reference ET (from windspeed, solar radiation, humidity, air temperature, and rainfall records), surface temperature, albedo, and so on. The observed data is collected at a series of tower in the middle Rio Grande Basin. The satellite image provides the instantaneous ET (ET_inst) only. Therefore, estimating 24 hour ET (ET_24) requires some assumptions. Two of these assumptions, which are (1) by assuming the instantaneous evaporative fraction (EF) is equal to the 24-hour averaged value, and (2) by assuming the instantaneous ETrF (same as `crop coefficient', and equal to instantaneous ET divided by instantaneous reference ET) is equal to the 24 hour averaged value, will be evaluated for the study area. Seasonal ET will be estimated by expanding the 24-hour ET proportionally to a reference ET that is derived from weather data. References: Bastiaanssen,W.G.M., M.Menenti, R.A. Feddes, and A.A.M. Holtslag, 1998, A remote sensing surface energy balance algorithm for land (SEBAL): 1

  20. Latent Heat Flux Estimate Through an Energy Water Balance Model and Land Surface Temperature from Remote Sensing

    NASA Astrophysics Data System (ADS)

    Corbari, Chiara; Sobrino, Jose A.; Mancini, Marco; Hidalgo, Victoria

    2011-01-01

    Soil moisture plays a key role in the terrestrial water cycle and is responsible for the partitioning of precipitation between runoff and infiltration. Moreover, surface soil moisture controls the redistribution of the incoming solar radiation on land surface into sensible and latent heat fluxes. Recent developments have been made to improve soil moisture dynamics predictions with hydrologic land surface models (LSMs) that compute water and energy balances between the land surface and the low atmosphere. However, most of the time soil moisture is confined to an internal numerical model variable mainly due to its intrinsic space and time variability and to the well known difficulties in assessing its value from remote sensing as from in situ measurements. In order to exploit the synergy between hydrological distributed models and thermal remote sensed data, FEST-EWB, a land surface model that solves the energy balance equation, was developed. In this hydrological model, the energy budget is solved looking for the representative thermodynamic equilibrium temperature (RET) defined as the land surface temperature that closes the energy balance equation. So using this approach, soil moisture is linked to the latent heat flux and then to LST. In this work the relationship between land surface temperature and soil moisture is analysed using LST from AHS (airborne hyperspectral scanner), with a spatial resolution of 2-4 m, LST from MODIS, with a spatial resolution of 1000 m, and thermal infrared radiometric ground measurements that are compared with the thermodynamic equilibrium temperature from the energy water balance model. Moreover soil moisture measurements were carried out during the airborne overpasses and then compared with SM from the hydrological model. An improvement of this well known inverse relationship between soil moisture and land surface temperature is obtained when the thermodynamic approach is used. The analysis of the scale effects of the different

  1. Evaluation of five lactation curve models fitted for fat:protein ratio of milk and daily energy balance.

    PubMed

    Buttchereit, N; Stamer, E; Junge, W; Thaller, G

    2010-04-01

    Selection for milk yield increases the metabolic load of dairy cows. The fat:protein ratio of milk (FPR) could serve as a measure of the energy balance status and might be used as a selection criterion to improve metabolic stability. The fit of different fixed and random regression models describing FPR and daily energy balance was tested to establish appropriate models for further genetic analyses. In addition, the relationship between both traits was evaluated for the best fitting model. Data were collected on a dairy research farm running a bull dam performance test. Energy balance was calculated using information on milk yield, feed intake per day, and live weight. Weekly FPR measurements were available. Three data sets were created containing records of 577 primiparous cows with observations from lactation d 11 to 180 as well as records of 613 primiparous cows and 96 multiparous cows with observations from lactation d 11 to 305. Five well-established parametric functions of days in milk (Ali and Schaeffer, Guo and Swalve, Wilmink, Legendre polynomials of third and fourth degree) were chosen for modeling the lactation curves. Evaluation of goodness of fit was based on the corrected Akaike information criterion, the Bayesian information criterion, correlation between the real observation and the estimated value, and on inspection of the residuals plotted against days in milk. The best model was chosen for estimation of correlations between both traits at different lactation stages. Random regression models were superior compared with the fixed regression models. In general, the Ali and Schaeffer function appeared most suitable for modeling both the fixed and the random regression part