Analysis of coals and biomass pyrolysis using the distributed activation energy model.
Li, Zhengqi; Liu, Chunlong; Chen, Zhichao; Qian, Juan; Zhao, Wei; Zhu, Qunyi
2009-01-01
The thermal decomposition of coals and biomass was studied using thermogravimetric analysis with the distributed activation energy model. The integral method resulted in Datong bituminous coal conversions of 3-73% at activation energies of 100-486 kJ/mol. The corresponding frequency factors were e(19.5)-e(59.0)s(-1). Jindongnan lean coal conversions were 8-52% at activation energies of 100-462 kJ/mol. Their corresponding frequency factors were e(13.0)-e(55.8)s(-1). The conversion of corn-stalk skins were 1-84% at activation energies of 62-169 kJ/mol with frequency factors of e(10.8)-e(26.5)s(-1). Datong bituminous coal, Jindongnan lean coal and corn-stalk skins had approximate Gaussian distribution functions with linear ln k(0) to E relationships.
1985-09-01
larger than the net energies of reaction for the same transitions ) represent energy needed for "freeing-up" of HMX or RDX molecules 70E. R. Lee, R. H...FACTORS FOR HMX AND RDX DECOMPOSITION Michael A. Schroeder DT!C .AECTE September 1985 SEP 3 0 8 * APPROVED FOR PUBUC RELEASE; DISTIR!UTION UNLIMITED. US...Final Activation Energies and Frequency Factors for HMX and RDX Decomposition b PERFORMING ORG. REPORT N, %1ER 7. AUTHOR(@) 6 CONTRACT OR GRANT NuMP
LaRiccia, Patrick J; Farrar, John T; Sammel, Mary D; Gallo, Joseph J
2008-07-01
To determine the efficacy of the food supplement OPC Factor to increase energy levels in healthy adults aged 45 to 65. Randomized, placebo-controlled, triple-blind crossover study. Twenty-five (25) healthy adults recruited from the University of Pennsylvania Health System. OPC Factor,trade mark (AlivenLabs, Lebanon, TN) a food supplement that contains oligomeric proanthocyanidins from grape seeds and pine bark along with other nutrient supplements including vitamins and minerals, was in the form of an effervescent powder. The placebo was similar in appearance and taste. Five outcome measurements were performed: (1) Energy subscale scores of the Activation-Deactivation Adjective Check List (AD ACL); (2) One (1) global question of percent energy change (Global Energy Percent Change); (3) One (1) global question of energy change measured on a Likert scale (Global Energy Scale Change); 4. One (1) global question of percent overall status change (Global Overall Status Percent Change); and (5) One (1) global question of overall status change measured on a Likert scale (Global Overall Status Scale Change). There were no carryover/period effects in the groups randomized to Placebo/Active Product sequence versus Active Product/Placebo sequence. Examination of the AD ACL Energy subscale scores for the Active Product versus Placebo comparison revealed no significant difference in the intention-to-treat (IT) analysis and the treatment received (TR) analysis. However, Global Energy Percent Change (p = 0.06) and Global Energy Scale Change (p = 0.09) both closely approached conventional levels of statistical significance for the active product in the IT analysis. Global Energy Percent Change (p = 0.05) and Global Energy Scale Change (p = 0.04) reached statistical significance in the TR analysis. A cumulative percent responders analysis graph indicated greater response rates for the active product. OPC Factor may increase energy levels in healthy adults aged 45-65 years. A larger study is recommended. Clinical Trials.gov identifier: NCT03318019.
Gaba, Ann; Zhang, Kuan; Moskowitz, Carol B; Boozer, Carol N; Marder, Karen
2008-10-01
Weight loss and energy metabolism are important clinical research areas in understanding the disease mechanisms in Huntington's disease. Having an accurate method to estimate expected total energy expenditure would likely facilitate the development of studies about these features of the disease. The Harris-Benedict equation is a formula commonly used to estimate basal energy expenditure of individuals, adjusted for height, weight, age and gender. This estimate is then multiplied by a physical activity factor to estimate total daily energy needs to maintain the given weight. Data from 24-h indirect calorimetry was utilized to derive an adjustment formula for the physical activity factor of the Harris-Benedict equation for 13 early to mid-stage Huntington's disease patients. The adjusted activity factor provided the most accurate estimate of energy needs. This adjusted formula can be used in clinical assessments of Huntington's disease patients, as well as in research studies when indirect calorimetry has not been performed.
Energy monitoring system based on human activity in the workplace
NASA Astrophysics Data System (ADS)
Mustafa, Nur Hanim; Husain, Mohd Nor; Aziz, Mohamad Zoinol Abidin Abdul; Othman, Mohd Azlishah; Malek, Fareq
2015-05-01
Human behaviors always related to day routine activities in a smart house directly give the significant factor to manage energy usage in human life. An Addition that, the factor will contribute to the best efficiency of the system. This paper will focus on the monitoring efficiency based on duration time in office hours around 8am until 5pm which depend on human behavior at working place. Besides that, the correlation coefficient method is used to show the relation between energy consumption and energy saving based on the total hours of time energy spent. In future, the percentages of energy monitoring system usage will be increase to manage energy saving based on human behaviors. This scenario will help to see the human activity in the workplace in order to get the energy saving and support world green environment.
Overview of the determinants of overweight and obesity: current evidence and research issues.
Hill, J O; Melanson, E L
1999-11-01
The prevalence of obesity has reached epidemic proportions in many countries around the world. However, the genetic and environmental factors contributing to obesity are incompletely understood. We reviewed studies relating to the regulation of energy balance and how these factors may contribute to the development of obesity. Although it is widely believed that genetics contribute significantly to the variability in body fatness, the available data do not support a role for defects in resting metabolic rate, substrate metabolism, dietary induced thermogenesis, or the energy cost of physical activity as significant causes of obesity. Furthermore, it is safe to say that the human genotype has not changed substantially over the past two to three decades. Data from several national surveys indicate that over the past few decades, there has been either a slight increase or a very modest decline in total energy and fat intake. This suggests that decreases in physical activity are a major contributing factor. Participation in leisure time physical activity is low but has remained relatively constant. However, an increased reliance on technology has substantially reduced work-related physical activity and the energy expenditure required for daily living. The most likely environmental factor contributing to the current obesity epidemic is a continued decline in daily energy expenditure that has not been matched by an equivalent reduction in energy intake. Because daily energy expenditure is decreasing, it is difficult for most people to restrict intake to meet energy requirements, and more and more people are becoming obese. Thus, increasing physical activity may be the strategy of choice for public health efforts to prevent obesity.
Daily energy expenditure, physical activity, and weight loss in Parkinson's disease patients
USDA-ARS?s Scientific Manuscript database
Patients with Parkinson's disease (PD) commonly exhibit weight loss (WL) which investigators attribute to various factors, including elevated energy expenditure. We tested the hypothesis that daily energy expenditure (DEE) and its components, resting energy expenditure (REE) and physical activity (P...
Real world experiences with nuclear science in the classroom: What an individual can do
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fox, M.R.
1991-06-01
Contributing factors to science illiteracy are discussed. Also, the educational institutions as a factor, and specific activities which have been achieved to help mitigate a small part of the problem are described. The activities undertaken with the grades K--12 in education communities related to energy education and to nuclear energy education are included.
NASA Astrophysics Data System (ADS)
Tang, Huanfeng; Huang, Zaiyin; Xiao, Ming; Liang, Min; Chen, Liying; Tan, XueCai
2017-09-01
The activities, selectivities, and stabilities of nanoparticles in heterogeneous reactions are size-dependent. In order to investigate the influencing laws of particle size and temperature on kinetic parameters in heterogeneous reactions, cubic nano-Cu2O particles of four different sizes in the range of 40-120 nm have been controllably synthesized. In situ microcalorimetry has been used to attain thermodynamic data on the reaction of Cu2O with aqueous HNO3 and, combined with thermodynamic principles and kinetic transition-state theory, the relevant reaction kinetic parameters have been evaluated. The size dependences of the kinetic parameters are discussed in terms of the established kinetic model and the experimental results. It was found that the reaction rate constants increased with decreasing particle size. Accordingly, the apparent activation energy, pre-exponential factor, activation enthalpy, activation entropy, and activation Gibbs energy decreased with decreasing particle size. The reaction rate constants and activation Gibbs energies increased with increasing temperature. Moreover, the logarithms of the apparent activation energies, pre-exponential factors, and rate constants were found to be linearly related to the reciprocal of particle size, consistent with the kinetic models. The influence of particle size on these reaction kinetic parameters may be explained as follows: the apparent activation energy is affected by the partial molar enthalpy, the pre-exponential factor is affected by the partial molar entropy, and the reaction rate constant is affected by the partial molar Gibbs energy. [Figure not available: see fulltext.
Analyzing Reaction Rates with the Distortion/Interaction‐Activation Strain Model
2017-01-01
Abstract The activation strain or distortion/interaction model is a tool to analyze activation barriers that determine reaction rates. For bimolecular reactions, the activation energies are the sum of the energies to distort the reactants into geometries they have in transition states plus the interaction energies between the two distorted molecules. The energy required to distort the molecules is called the activation strain or distortion energy. This energy is the principal contributor to the activation barrier. The transition state occurs when this activation strain is overcome by the stabilizing interaction energy. Following the changes in these energies along the reaction coordinate gives insights into the factors controlling reactivity. This model has been applied to reactions of all types in both organic and inorganic chemistry, including substitutions and eliminations, cycloadditions, and several types of organometallic reactions. PMID:28447369
Code of Federal Regulations, 2013 CFR
2013-01-01
... 10 Energy 4 2013-01-01 2013-01-01 false Exceptions to the rules against age discrimination. Reasonable factors other than age. 1040.87 Section 1040.87 Energy DEPARTMENT OF ENERGY (GENERAL PROVISIONS) NONDISCRIMINATION IN FEDERALLY ASSISTED PROGRAMS OR ACTIVITIES Nondiscrimination on the Basis of Age-Age...
Nonexercise activity thermogenesis (NEAT): environment and biology.
Levine, James A
2004-05-01
Nonexercise activity thermogenesis (NEAT) is the energy expended for everything that is not sleeping, eating, or sports-like exercise. It includes the energy expended walking to work, typing, performing yard work, undertaking agricultural tasks, and fidgeting. NEAT can be measured by one of two approaches. The first is to measure or estimate total NEAT. Here, total daily energy expenditure is measured, and from it "basal metabolic rate-plus-thermic effect of food" is subtracted. The second is the factoral approach, whereby the components of NEAT are quantified, and total NEAT is calculated by summing these components. The amount of NEAT that humans perform represents the product of the amount and types of physical activities and the thermogenic cost of each activity. The factors that impact a human's NEAT are readily divisible into environmental factors, such as occupation or dwelling within a "concrete jungle," and biological factors such as weight, gender, and body composition. The combined impact of these factors explains the substantial variance in human NEAT. The variability in NEAT might be viewed as random, but human and animal data contradict this. It appears that changes in NEAT subtly accompany experimentally induced changes in energy balance and are important in the physiology of weight change. Inadequate modulation of NEAT plus a sedentary lifestyle may thus be important in obesity. It then becomes intriguing to dissect mechanistic studies that delineate how NEAT is regulated into neural, peripheral, and humoral factors. A scheme is described in this review in which NEAT corresponds to a carefully regulated "tank" of physical activity that is crucial for weight control.
Energetics of photosynthetic glow peaks
DeVault, Don; Govindjee; Arnold, William
1983-01-01
By postulating temperature-dependent equilibria between two or more electron carriers acting as traps for electrons or holes, it is possible to modify the Randall-Wilkins theory of thermoluminescence so as to explain the abnormally large apparent activation energies and apparent frequency factors observed in photosynthetic glow curves when fitted by unmodified Randall-Wilkins theory. The equilibria serve to inhibit the formation of the light-emitting excited state by withholding the needed precursor state. When the inhibition is released at higher temperature by shift of equilibrium with temperature, the rise of the glow peak can be much faster than would result from Arrhenius behavior based on the true activation energy and so appears to correspond to a higher activation energy accompanied by a larger frequency factor. From another viewpoint, the enthalpy changes, ΔH, of the equilibria tend to add to the activation energy. Similarly the entropy changes, ΔS, of the equilibria tend to add to the entropy of activation, giving the large apparent frequency factors. The positive values of ΔS needed would correspond to entropy decreases in the forward early electron transport. A comparison of the glow peaks obtained by different workers is also presented. PMID:16593283
Extinction cross-section suppression and active acoustic invisibility cloaking
NASA Astrophysics Data System (ADS)
Mitri, F. G.
2017-10-01
Invisibility in its canonical form requires rendering a zero extinction cross-section (or energy efficiency) from an active or a passive object. This work demonstrates the successful theoretical realization of this physical effect for an active cylindrically radiating acoustic body, undergoing periodic axisymmetric harmonic vibrations near a flat rigid boundary. Radiating, amplification and extinction cross-sections of the active source are defined. Assuming monopole and dipole modal oscillations of the circular source, conditions are found where the extinction energy efficiency factor of the active source vanishes, achieving total invisibility with minimal influence of the source size. It also takes positive or negative values, depending on its size and distance from the boundary. Moreover, the amplification energy efficiency factor is negative for the acoustically-active source. These effects also occur for higher-order modal oscillations of the active source. The results find potential applications in the development of acoustic cloaking devices and invisibility.
Du, Zhijia; Wood, David L.; Daniel, Claus; ...
2017-02-09
We present that increasing electrode thickness, thus increasing the volume ratio of active materials, is one effective method to enable the development of high energy density Li-ion batteries. In this study, an energy density versus power density optimization of LiNi 0.8Co 0.15Al 0.05O 2 (NCA)/graphite cell stack was conducted via mathematical modeling. The energy density was found to have a maximum point versus electrode thickness (critical thickness) at given discharging C rates. The physics-based factors that limit the energy/power density of thick electrodes were found to be increased cell polarization and underutilization of active materials. The latter is affected bymore » Li-ion diffusion in active materials and Li-ion depletion in the electrolyte phase. Based on those findings, possible approaches were derived to surmount the limiting factors. Finally, the improvement of the energy–power relationship in an 18,650 cell was used to demonstrate how to optimize the thick electrode parameters in cell engineering.« less
Novak, Colleen M; Burghardt, Paul R; Levine, James A
2012-03-01
Running wheels are commonly employed to measure rodent physical activity in a variety of contexts, including studies of energy balance and obesity. There is no consensus on the nature of wheel-running activity or its underlying causes, however. Here, we will begin by systematically reviewing how running wheel availability affects physical activity and other aspects of energy balance in laboratory rodents. While wheel running and physical activity in the absence of a wheel commonly correlate in a general sense, in many specific aspects the two do not correspond. In fact, the presence of running wheels alters several aspects of energy balance, including body weight and composition, food intake, and energy expenditure of activity. We contend that wheel-running activity should be considered a behavior in and of itself, reflecting several underlying behavioral processes in addition to a rodent's general, spontaneous activity. These behavioral processes include defensive behavior, predatory aggression, and depression- and anxiety-like behaviors. As it relates to energy balance, wheel running engages several brain systems-including those related to the stress response, mood, and reward, and those responsive to growth factors-that influence energy balance indirectly. We contend that wheel-running behavior represents factors in addition to rodents' tendency to be physically active, engaging additional neural and physiological mechanisms which can then independently alter energy balance and behavior. Given the impact of wheel-running behavior on numerous overlapping systems that influence behavior and physiology, this review outlines the need for careful design and interpretation of studies that utilize running wheels as a means for exercise or as a measurement of general physical activity. Copyright © 2012 Elsevier Ltd. All rights reserved.
[Regulatory mechanisms in focal cerebral ischemia. New possibilities in neuroprotective therapy].
Nagy, Zoltán; Simon, László; Bori, Zoltán
2002-03-20
Permanent or temporary disruption of cerebral blood flow rapidly depletes brain regions of their limited energy reserves (glycogen, glucose, oxygen, ATP) leading to an energy crisis. Tissue damage occurs due to the energy crisis. The central part of the damage, the ischaemic "core" region is surrounded by zones of the shell-like penumbra. Necrotic, as well as apoptotic cell death could be identified in the penumbra. Going away from the ischaemic core different neurochemical processes are occurring by space and time. "Immediate early response" genes (c-fos, fos-B, c-Jun, krox 20, 24) are activated, heatshock proteins (hsp 70, 72, HSF, HSE, HIF), cytokines (TNF-alpha, IL-1 beta), inflammatory factors (COX), adhesion and glial factors (ICAM-1, ELAM-1, P-selectin), vasoactive factors (IL-6, -10, PAF), reactive oxigen radicals and connected factors (O2, OH, NO, NOS, SOD) are produced within minutes and hours. Cell deaths, necrosis and apoptosis due to the activation of calpains, caspases and nucleases occur in days. In parallel, growth factors and plasticity proteins (BDNF, NGF, TGF-beta, VEGF, PDGF, GAP-43) are activated as a basis of functional rehabilitation.
Prediction equation for estimating total daily energy requirements of special operations personnel.
Barringer, N D; Pasiakos, S M; McClung, H L; Crombie, A P; Margolis, L M
2018-01-01
Special Operations Forces (SOF) engage in a variety of military tasks with many producing high energy expenditures, leading to undesired energy deficits and loss of body mass. Therefore, the ability to accurately estimate daily energy requirements would be useful for accurate logistical planning. Generate a predictive equation estimating energy requirements of SOF. Retrospective analysis of data collected from SOF personnel engaged in 12 different SOF training scenarios. Energy expenditure and total body water were determined using the doubly-labeled water technique. Physical activity level was determined as daily energy expenditure divided by resting metabolic rate. Physical activity level was broken into quartiles (0 = mission prep, 1 = common warrior tasks, 2 = battle drills, 3 = specialized intense activity) to generate a physical activity factor (PAF). Regression analysis was used to construct two predictive equations (Model A; body mass and PAF, Model B; fat-free mass and PAF) estimating daily energy expenditures. Average measured energy expenditure during SOF training was 4468 (range: 3700 to 6300) Kcal·d- 1 . Regression analysis revealed that physical activity level ( r = 0.91; P < 0.05) and body mass ( r = 0.28; P < 0.05; Model A), or fat-free mass (FFM; r = 0.32; P < 0.05; Model B) were the factors that most highly predicted energy expenditures. Predictive equations coupling PAF with body mass (Model A) and FFM (Model B), were correlated ( r = 0.74 and r = 0.76, respectively) and did not differ [mean ± SEM: Model A; 4463 ± 65 Kcal·d - 1 , Model B; 4462 ± 61 Kcal·d - 1 ] from DLW measured energy expenditures. By quantifying and grouping SOF training exercises into activity factors, SOF energy requirements can be predicted with reasonable accuracy and these equations used by dietetic/logistical personnel to plan appropriate feeding regimens to meet SOF nutritional requirements across their mission profile.
Johar, Kaid; Priya, Anusha; Wong-Riley, Margaret T T
2012-11-23
NRF-1 regulates mediators of neuronal activity and energy generation. NRF-1 transcriptionally regulates Na(+)/K(+)-ATPase subunits α1 and β1. NRF-1 functionally regulates mediators of energy consumption in neurons. NRF-1 mediates the tight coupling of neuronal activity, energy generation, and energy consumption at the molecular level. Energy generation and energy consumption are tightly coupled to neuronal activity at the cellular level. Na(+)/K(+)-ATPase, a major energy-consuming enzyme, is well expressed in neurons rich in cytochrome c oxidase, an important enzyme of the energy-generating machinery, and glutamatergic receptors that are mediators of neuronal activity. The present study sought to test our hypothesis that the coupling extends to the molecular level, whereby Na(+)/K(+)-ATPase subunits are regulated by the same transcription factor, nuclear respiratory factor 1 (NRF-1), found recently by our laboratory to regulate all cytochrome c oxidase subunit genes and some NMDA and AMPA receptor subunit genes. By means of multiple approaches, including in silico analysis, electrophoretic mobility shift and supershift assays, in vivo chromatin immunoprecipitation, promoter mutational analysis, and real-time quantitative PCR, NRF-1 was found to functionally bind to the promoters of Atp1a1 and Atp1b1 genes but not of the Atp1a3 gene in neurons. The transcripts of Atp1a1 and Atp1b1 subunit genes were up-regulated by KCl and down-regulated by tetrodotoxin. Atp1b1 is positively regulated by NRF-1, and silencing of NRF-1 with small interference RNA blocked the up-regulation of Atp1b1 induced by KCl, whereas overexpression of NRF-1 rescued these transcripts from being suppressed by tetrodotoxin. On the other hand, Atp1a1 is negatively regulated by NRF-1. The binding sites of NRF-1 on Atp1a1 and Atp1b1 are conserved among mice, rats, and humans. Thus, NRF-1 regulates key Na(+)/K(+)-ATPase subunits and plays an important role in mediating the tight coupling between energy consumption, energy generation, and neuronal activity at the molecular level.
A hypothesis: factor VII governs clot formation, tissue repair and apoptosis.
Coleman, Lewis S
2007-01-01
A hypothesis: thrombin is a "Universal Enzyme of Energy Transduction" that employs ATP energy in flowing blood to activate biochemical reactions and cell effects in both hemostasis and tissue repair. All cells possess PAR-1 (thrombin) receptors and are affected by thrombin elevations, and thrombin effects on individual cell types are determined by their unique complement of PAR-1 receptors. Disruption of the vascular endothelium (VE) activates a tissue repair mechanism (TRM) consisting of the VE, tissue factor (TF), and circulating Factors VII, IX and X that governs localized thrombin elevations to activate clot formation and cellular effects that repair tissue damage. The culmination of the repair process occurs with the restoration of the VE followed by declines in thrombin production that causes Apoptosis ("programmed cell death") in wound-healing fibroblasts, which functions as a mechanism to draw wound edges together. The location and magnitude of TRM activity governs the location and magnitude of Factor VIII activity and clot formation, but the large size of Factor VIII prevents it from penetrating the clot formed by its activity, so that its effects are self-limiting. Factors VII, IX and X function primarily as tissue repair enzymes, while Factor VIII and Factor XIII are the only serine protease enzymes in the "Coagulation Cascade" that are exclusively associated with hemostasis.
Research on Influencing Factors of Salespeople's Empowerment Readiness in Green Energy Enterprise
NASA Astrophysics Data System (ADS)
Dong, Yuan; Liu, Xiaohui
As market competition in green energy enterprises continues to intensify, marketing activities are enlarging and customer demand is increasingly growing and diversifying. More and more green energy enterprises have empowered their own salespeople. And managers in green energy enterprises are more concerned with the issues which employees suit to be empowered and which factors will influence employee empowerment readiness. This paper proposes the definition of salespeople's empowerment readiness, analyzes influencing factors of salespeople's empowerment readiness, discusses the effect mechanism of influencing factors of salespeople's empowerment readiness, finally, and puts forward some suggestions to enhance salespeople's empowerment readiness from the perspective of human resource management practice.
Environmental influences on food choice, physical activity and energy balance.
Popkin, Barry M; Duffey, Kiyah; Gordon-Larsen, Penny
2005-12-15
In this paper, the environment is defined as the macro- and community-level factors, including physical, legal and policy factors, that influence household and individual decisions. Thus, environment is conceived as the external context in which household and individual decisions are made. This paper reviews the literature on the ways the environment affects diet, physical activity, and obesity. Other key environmental factors discussed include economic, legal, and policy factors. Behind the major changes in diet and physical activity in the US and globally lie large shifts in food production, processing, and distribution systems as well as food shopping and eating options, resulting in the increase in availability of energy-dense foods. Similarly, the ways we move at home, work, leisure, and travel have shifted markedly, resulting in substantial reductions in energy expenditure. Many small area studies have linked environmental shifts with diet and activity changes. This paper begins with a review of environmental influences on diet and physical activity, and includes the discussion of two case studies on environmental influences on physical activity in a nationally representative sample of US adolescents. The case studies illustrate the important role of physical activity resources and the inequitable distribution of such activity-related facilities and resources, with high minority, low educated populations at strong disadvantage. Further, the research shows a significant association of such facilities with individual-level health behavior. The inequity in environmental supports for physical activity may underlie health disparities in the US population.
Estimation of shelf life of natural rubber latex exam-gloves based on creep behavior.
Das, Srilekha Sarkar; Schroeder, Leroy W
2008-05-01
Samples of full-length glove-fingers cut from chlorinated and nonchlorinated latex medical examination gloves were aged for various times at several fixed temperatures and 25% relative humidity. Creep testing was performed using an applied stress of 50 kPa on rectangular specimens (10 mm x 8 mm) of aged and unaged glove fingers as an assessment of glove loosening during usage. Variations in creep curves obtained were compared to determine the threshold aging time when the amount of creep became larger than the initial value. These times were then used in various models to estimate shelf lives at lower temperatures. Several different methods of extrapolation were used for shelf-life estimation and comparison. Neither Q-factor nor Arrhenius activation energies, as calculated from 10 degrees C interval shift factors, were constant over the temperature range; in fact, both decreased at lower temperatures. Values of Q-factor and activation energies predicted up to 5 years of shelf life. Predictions are more sensitive to values of activation energy as the storage temperature departs from the experimental aging data. Averaging techniques for prediction of average activation energy predicted the longest shelf life as the curvature is reduced. Copyright 2007 Wiley Periodicals, Inc.
Verdeguer, Francisco; Soustek, Meghan S.; Hatting, Maximilian; Blättler, Sharon M.; McDonald, Devin; Barrow, Joeva J.
2015-01-01
Mitochondrial oxidative and thermogenic functions in brown and beige adipose tissues modulate rates of energy expenditure. It is unclear, however, how beige or white adipose tissue contributes to brown fat thermogenic function or compensates for partial deficiencies in this tissue and protects against obesity. Here, we show that the transcription factor Yin Yang 1 (YY1) in brown adipose tissue activates the canonical thermogenic and uncoupling gene expression program. In contrast, YY1 represses a series of secreted proteins, including fibroblast growth factor 21 (FGF21), bone morphogenetic protein 8b (BMP8b), growth differentiation factor 15 (GDF15), angiopoietin-like 6 (Angptl6), neuromedin B, and nesfatin, linked to energy expenditure. Despite substantial decreases in mitochondrial thermogenic proteins in brown fat, mice lacking YY1 in this tissue are strongly protected against diet-induced obesity and exhibit increased energy expenditure and oxygen consumption in beige and white fat depots. The increased expression of secreted proteins correlates with elevation of energy expenditure and promotion of beige and white fat activation. These results indicate that YY1 in brown adipose tissue controls antagonistic gene expression programs associated with energy balance and maintenance of body weight. PMID:26503783
Airframe technology for aircraft energy efficiency. [economic factors
NASA Technical Reports Server (NTRS)
James, R. L., Jr.; Maddalon, D. V.
1984-01-01
The economic factors that resulted in the implementation of the aircraft energy efficiency program (ACEE) are reviewed and airframe technology elements including content, progress, applications, and future direction are discussed. The program includes the development of laminar flow systems, advanced aerodynamics, active controls, and composite structures.
Garapati, Prashanth; Feil, Regina; Lunn, John Edward; Van Dijck, Patrick; Balazadeh, Salma; Mueller-Roeber, Bernd
2015-01-01
Plants respond to low carbon supply by massive reprogramming of the transcriptome and metabolome. We show here that the carbon starvation-induced NAC (for NO APICAL MERISTEM/ARABIDOPSIS TRANSCRIPTION ACTIVATION FACTOR/CUP-SHAPED COTYLEDON) transcription factor Arabidopsis (Arabidopsis thaliana) Transcription Activation Factor1 (ATAF1) plays an important role in this physiological process. We identified TREHALASE1, the only trehalase-encoding gene in Arabidopsis, as a direct downstream target of ATAF1. Overexpression of ATAF1 activates TREHALASE1 expression and leads to reduced trehalose-6-phosphate levels and a sugar starvation metabolome. In accordance with changes in expression of starch biosynthesis- and breakdown-related genes, starch levels are generally reduced in ATAF1 overexpressors but elevated in ataf1 knockout plants. At the global transcriptome level, genes affected by ATAF1 are broadly associated with energy and carbon starvation responses. Furthermore, transcriptional responses triggered by ATAF1 largely overlap with expression patterns observed in plants starved for carbon or energy supply. Collectively, our data highlight the existence of a positively acting feedforward loop between ATAF1 expression, which is induced by carbon starvation, and the depletion of cellular carbon/energy pools that is triggered by the transcriptional regulation of downstream gene regulatory networks by ATAF1. PMID:26149570
Energy balance, insulin-resistance biomarkers and breast cancer risk
Fair, Alecia Malin; Dai, Qi; Shu, Xiao-Ou; Matthews, Charles E.; Yu, Herbert; Jin, Fan; Gao, Yu-Tang; Zheng, Wei
2007-01-01
Background American women are five times more likely to be at risk for breast cancer than women from Asian countries. Epidemiologic studies have linked energy balance to an increased risk of breast cancer, yet few studies have investigated potential mediators of this association with Chinese women. We examined the above association by blood levels of insulin-like growth factors, binding proteins, and C-peptide in the Shanghai Breast Cancer Study (SBCS), a case-control study conducted among 1459 breast cancer cases and 1556 healthy Chinese women from 1996 and 1998. Methods In-person surveys were used to collect data on energy intake, anthropometric measures, exercise/sport activity, and occupational activity. The present analyses consisted of 397 cases and 397 controls whose blood samples were measured for levels of insulin-like growth factors ( IGFs), insulin growth-factor binding protein 3, (IGFBP-3) C-peptide and the relationship with physical activity status, total energy intake, and body fat distribution. Results Body mass index [BMI] and waist-to-hip ratio [WHR] were significantly positively correlated with IGFBP-3 and C-peptide. Adult exercise/sport activity was significantly negatively correlated with insulin-like growth factor 1(IGF-I). C-peptide levels increased with increasing quartiles of WHR (p for trend <0.01). Additional analyses were performed to evaluate whether the association of energy balance measures with breast cancer risk changed after adjustment for IGFs, IGFBP-3 and C-peptide biomarkers. The associations attenuated, but none of them changed substantially. Conclusions Insulin resistance biomarkers may partially explain the association between positive energy balance and breast cancer risk, but future studies are needed to identify the underlying complex biological mechanisms of action for breast cancer prevention. PMID:17646056
Brand, Caroline; Dencks, Stefanie; Schmitz, Georg; Mühlmeister, Mareike; Stypmann, Jörg; Ross, Rebecca; Hintelmann, Heike; Schliemann, Christoph; Müller-Tidow, Carsten; Mesters, Rolf M; Berdel, Wolfgang E; Schwöppe, Christian
2015-07-01
To enhance the regional antitumor activity of the vascular-targeting agent truncated tissue factor (tTF)-NGR by combining the therapy with low-energy ultrasound (US) treatment. For the in vitro US exposure of human umbilical vein endothelial cells (HUVECs), cells were put in the focus of a US transducer. For analysis of the US-induced phosphatidylserine (PS) surface concentration on HUVECs, flow cytometry was used. To demonstrate the differences in the procoagulatory efficacy of TF-derivative tTF-NGR on binding to HUVECs with a low versus high surface concentration of PS, we performed factor X activation assays. For low-energy US pretreatment, HT1080 fibrosarcoma xenotransplant-bearing nude mice were treated by tumor-regional US-mediated stimulation (ie, destruction) of microbubbles. The therapy cohorts received the tumor vessel-infarcting tTF-NGR protein with or without US pretreatment (5 minutes after US stimulation via intraperitoneal injection on 3 consecutive days). Combination therapy experiments with xenotransplant-bearing nude mice significantly increased the antitumor activity of tTF-NGR by regional low-energy US destruction of vascular microbubbles in tumor vessels shortly before application of tTF-NGR (P < .05). Mechanistic studies proved the upregulation of anionic PS on the outer leaflet of the lipid bilayer of endothelial cell membranes by low-energy US and a consecutive higher potential of these preapoptotic endothelial cells to activate coagulation via tTF-NGR and coagulation factor X as being a basis for this synergistic activity. Combining retargeted tTF to tumor vessels with proapoptotic stimuli for the tumor vascular endothelium increases the antitumor effects of tumor vascular infarction. Ultrasound treatment may thus be useful in this respect for regional tumor therapy. © 2015 by the American Institute of Ultrasound in Medicine.
Occupational energy expenditure and leisure-time physical activity.
Kaleta, Dorota; Jegier, Anna
2005-01-01
In the majority of countries around the world, a decrease in the leisure-time physical activity is observed. The aim of the study was to evaluate the correlation between occupational energy expenditure and leisure-time physical activity. Moreover, the correlation between other factors and leisure-time physical activity was assessed. The study was performed in a randomly selected group of full-time employees (272 men and 236 women) living in the city of Lódź. Logistic regression was used to estimate odds ratios and 95% confidence intervals as well as to control the effects of occupational workload and leisure-time physical activity limitations. Physical activity was determined by the Seven Day Physical Activity Recall (SDPAR). Leisure-time physical activity was strongly associated with energy expenditure on occupational physical activity in men and women. Among men who expended 4000 kcal/week or more on occupational physical activity, the risk of inactivity at leisure was 1.5 times higher than in men whose weekly energy expenditure on occupational activity did not exceed 4000 kcal (adjusted OR = 1.33, 95% CI: 1.06-2.34). Among women who expended 3500 kcal/week or more on occupational physical activity, the risk of not taking up leisure-time physical activity was also higher as compared to those whose weekly energy expenditure on occupational activity was lower than 3500 kcal (adjusted OR = 1.41, 95% CI: 1.09-3.40). Prophylactic schedules associated with the improvement of leisure-time physical activity should be addressed to all adults, particularly to blue-collar workers. Future programs aimed at increasing physical activity in adults should consider work-related factors.
Renewable Energy for Rural Schools.
ERIC Educational Resources Information Center
Jimenez, Antonio C.; Lawand, Tom
Although education in rural communities is an important priority, in many cases, electricity is not available to support rural educational activities. Renewable energy systems present a reasonable solution to support activities such as lighting, computers, telecommunications, and distance learning. There are certain factors and criteria that need…
The Catalytic Function of Enzymes.
ERIC Educational Resources Information Center
Splittgerber, Allan G.
1985-01-01
Discusses: structure of the enzyme molecule; active site; reaction mechanism; transition state; factors affecting enzyme reaction rates, concentration of enzyme; concentration of substrate; product concentration; temperature effects and pH effects; factors causing a lowering of activation energy; proximity and orientation effects; substrate strain…
Choo, Jina; Elci, Okan U.; Yang, Kyeongra; Turk, Melanie W.; Styn, Mindi A.; Sereika, Susan M.; Music, Edvin; Burke, Lora E.
2012-01-01
Few studies have reported longitudinal relationships between physical activity (PA) and cardiometabolic risk factors over time using repeated assessments in overweight or obese adults. We conducted a longitudinal study in 127 participants (81% with body mass index > 30 kg/m2) who completed a 12-month behavioral intervention for weight loss between 2003 and 2005 in Pittsburgh, PA, USA. Using absolute change scores from baseline to each time point (i.e., 6 and 12 months) for all studied variables (Δ = time point – baseline), we performed mixed effects modeling to examine relationships between PA and cardiometabolic risk factors, after adjusting for body weight, energy intake and other covariates (i.e., age, gender, and ethnicity). PA was assessed as energy expenditure (kcal/week) using the Paffenbarger activity questionnaire. Over the 12-month period, energy expenditure increased (Δ1,370 kcal/week at 6 months vs. Δ886 kcal/week at 12 months); body weight decreased (Δ8.9 kg at 6 months vs. Δ8.4 kg at 12 months). The average increase in energy expenditure over 12 months was significantly and independently related to reductions in total cholesterol (F = 6.25, p = 0.013), low-density lipoprotein cholesterol (LDL-C) (F = 5.08, p = 0.025) and fasting blood glucose (F = 5.10, p = 0.025), but not to other risk factors (i.e., fasting insulin, high-density lipoprotein cholesterol, triglycerides, and waist circumference). In conclusion, among overweight and obese adults undergoing a weight loss intervention, increased energy expenditure over 12 months may improve total cholesterol and LDL-C, important coronary risk factors, and fasting blood glucose, a metabolic risk factor. PMID:19806358
USDA-ARS?s Scientific Manuscript database
Patients with Parkinson's disease (PD) commonly exhibit weight loss, which investigators attribute to various factors, including elevated resting energy expenditure. We tested the hypothesis that daily energy expenditure (DEE) and its components, resting energy expenditure (REF) and physical activit...
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 interventions may be a practical approach to promote physical activity in man.
Ringus, Daina L.; Gaballa, Ahmed; Helmann, John D.; Wiedmann, Martin
2013-01-01
Sigma B (σB) is an alternative sigma factor that regulates the general stress response in Bacillus subtilis and in many other Gram-positive organisms. σB activity in B. subtilis is tightly regulated via at least three distinct pathways within a complex signal transduction cascade in response to a variety of stresses, including environmental stress, energy stress, and growth at high or low temperatures. We probed the ability of fluoro-phenyl-styrene-sulfonamide (FPSS), a small-molecule inhibitor of σB activity in Listeria monocytogenes, to inhibit σB activity in B. subtilis through perturbation of signal transduction cascades under various stress conditions. FPSS inhibited the activation of σB in response to multiple categories of stress known to induce σB activity in B. subtilis. Specifically, FPSS prevented the induction of σB activity in response to energy stress, including entry into stationary phase, phosphate limitation, and azide stress. FPSS also inhibited chill induction of σB activity in a ΔrsbV strain, suggesting that FPSS does not exclusively target the RsbU and RsbP phosphatases or the anti–anti-sigma factor RsbV, all of which contribute to posttranslational regulation of σB activity. Genetic and biochemical experiments, including artificial induction of σB, analysis of the phosphorylation state of the anti–anti-sigma factor RsbV, and in vitro transcription assays, indicate that while FPSS does not bind directly to σB to inhibit activity, it appears to prevent the release of B. subtilis σB from its anti-sigma factor RsbW. PMID:23524614
Public perceptions of energy consumption and savings
Attari, Shahzeen Z.; DeKay, Michael L.; Davidson, Cliff I.; Bruine de Bruin, Wändi
2010-01-01
In a national online survey, 505 participants reported their perceptions of energy consumption and savings for a variety of household, transportation, and recycling activities. When asked for the most effective strategy they could implement to conserve energy, most participants mentioned curtailment (e.g., turning off lights, driving less) rather than efficiency improvements (e.g., installing more efficient light bulbs and appliances), in contrast to experts’ recommendations. For a sample of 15 activities, participants underestimated energy use and savings by a factor of 2.8 on average, with small overestimates for low-energy activities and large underestimates for high-energy activities. Additional estimation and ranking tasks also yielded relatively flat functions for perceived energy use and savings. Across several tasks, participants with higher numeracy scores and stronger proenvironmental attitudes had more accurate perceptions. The serious deficiencies highlighted by these results suggest that well-designed efforts to improve the public's understanding of energy use and savings could pay large dividends. PMID:20713724
Hepatic CREB3L3 controls whole-body energy homeostasis and improves obesity and diabetes.
Nakagawa, Yoshimi; Satoh, Aoi; Yabe, Sachiko; Furusawa, Mika; Tokushige, Naoko; Tezuka, Hitomi; Mikami, Motoki; Iwata, Wakiko; Shingyouchi, Akiko; Matsuzaka, Takashi; Kiwata, Shiori; Fujimoto, Yuri; Shimizu, Hidehisa; Danno, Hirosuke; Yamamoto, Takashi; Ishii, Kiyoaki; Karasawa, Tadayoshi; Takeuchi, Yoshinori; Iwasaki, Hitoshi; Shimada, Masako; Kawakami, Yasushi; Urayama, Osamu; Sone, Hirohito; Takekoshi, Kazuhiro; Kobayashi, Kazuto; Yatoh, Shigeru; Takahashi, Akimitsu; Yahagi, Naoya; Suzuki, Hiroaki; Yamada, Nobuhiro; Shimano, Hitoshi
2014-12-01
Transcriptional regulation of metabolic genes in the liver is the key to maintaining systemic energy homeostasis during starvation. The membrane-bound transcription factor cAMP-responsive element-binding protein 3-like 3 (CREB3L3) has been reported to be activated during fasting and to regulate triglyceride metabolism. Here, we show that CREB3L3 confers a wide spectrum of metabolic responses to starvation in vivo. Adenoviral and transgenic overexpression of nuclear CREB3L3 induced systemic lipolysis, hepatic ketogenesis, and insulin sensitivity with increased energy expenditure, leading to marked reduction in body weight, plasma lipid levels, and glucose levels. CREB3L3 overexpression activated gene expression levels and plasma levels of antidiabetic hormones, including fibroblast growth factor 21 and IGF-binding protein 2. Amelioration of diabetes by hepatic activation of CREB3L3 was also observed in several types of diabetic obese mice. Nuclear CREB3L3 mutually activates the peroxisome proliferator-activated receptor (PPAR) α promoter in an autoloop fashion and is crucial for the ligand transactivation of PPARα by interacting with its transcriptional regulator, peroxisome proliferator-activated receptor gamma coactivator-1α. CREB3L3 directly and indirectly controls fibroblast growth factor 21 expression and its plasma level, which contributes at least partially to the catabolic effects of CREB3L3 on systemic energy homeostasis in the entire body. Therefore, CREB3L3 is a therapeutic target for obesity and diabetes.
Energy balance, physical activity, and cancer risk.
Fair, Alecia Malin; Montgomery, Kara
2009-01-01
This chapter posits that cancer is a complex and multifactorial process as demonstrated by the expression and production of key endocrine and steroid hormones that intermesh with lifestyle factors (physical activity, body size, and diet) in combination to heighten cancer risk. Excess weight has been associated with increased mortality from all cancers combined and for cancers of several specific sites. The prevalence of obesity has reached epidemic levels in many parts of the world; more than 1 billion adults are overweight with a body mass index (BMI) exceeding 25. Overweight and obesity are clinically defined indicators of a disease process characterized by the accumulation of body fat due to an excess of energy intake (nutritional intake) relative to energy expenditure (physical activity). When energy intake exceeds energy expenditure over a prolonged period of time, the result is a positive energy balance (PEB), which leads to the development of obesity. This physical state is ideal for intervention and can be modulated by changes in energy intake, expenditure, or both. Nutritional intake is a modifiable factor in the energy balance-cancer linkage primarily tested by caloric restriction studies in animals and the effect of energy availability. Restriction of calories by 10 to 40% has been shown to decrease cell proliferation, increasing apoptosis through anti-angiogenic processes. The potent anticancer effect of caloric restriction is clear, but caloric restriction alone is not generally considered to be a feasible strategy for cancer prevention in humans. Identification and development of preventive strategies that "mimic" the anticancer effects of low energy intake are desirable. The independent effect of energy intake on cancer risk has been difficult to estimate because body size and physical activity are strong determinants of total energy expenditure. The mechanisms that account for the inhibitory effects of physical activity on the carcinogenic process are reduction in fat stores, activity related changes in sex-hormone levels, altered immune function, effects in insulin and insulin-like growth factors, reduced free radical generation, and direct effect on the tumor. Epidemiologic evidence posits that the cascade of actions linking overweight and obesity to carcinogenesis are triggered by the endocrine and metabolic system. Perturbations to these systems result in the alterations in the levels of bioavailable growth factors, steroid hormones, and inflammatory markers. Elevated serum concentrations of insulin lead to a state of hyperinsulinemia. This physiological state causes a reduction in insulin-like growth factor-binding proteins and promotes the synthesis and biological activity of insulin-like growth factor (IGF)-I, which regulates cellular growth in response to available energy and nutrients from diet and body reserves. In vitro studies have clearly established that both insulin and IGF-I act as growth factors that promote cell proliferation and inhibit apoptosis. Insulin also affects on the synthesis and biological availability of the male and female sex steroids, including androgens, progesterone, and estrogens. Experimental and clinical evidence also indicates a central role of estrogens and progesterone in regulating cellular differentiation, proliferation, and apoptosis induction. Hyperinsulinemia is also associated with alterations in molecular systems such as endogenous hormones and adipokines that regulate inflammatory responses. Obesity-related dysregulation of adipokines has the ability to contribute to tumorigenesis and tumor invasion via metastatic potential. Given the substantial level of weight gain in industrialized countries in the last two decades, there is great interest in understanding all of the mechanisms by which obesity contributes to the carcinogenic process. Continued focus must be directed to understanding the various relationships between specific nutrients and dietary components and cancer cause and prevention. A reductionist approach is not sufficient for the basic biological mechanisms underlying the effect of diet and physical activity on cancer. The joint association between energy balance and cancer risk are hypothesized to share the same underlying mechanisms, the amplification of chemical mediators that modulate cancer risk depending on the responsiveness to those hormones to the target tissue of interest. Disentangling the connection between obesity, the insulin-IGF axis, endogenous hormones, inflammatory markers, and their molecular interaction is vital.
IEA EBC annex 53: Total energy use in buildings—Analysis and evaluation methods
DOE Office of Scientific and Technical Information (OSTI.GOV)
Yoshino, Hiroshi; Hong, Tianzhen; Nord, Natasa
One of the most significant barriers to achieving deep building energy efficiency is a lack of knowledge about the factors determining energy use. In fact, there is often a significant discrepancy between designed and real energy use in buildings, which is poorly understood but are believed to have more to do with the role of human behavior than building design. Building energy use is mainly influenced by six factors: climate, building envelope, building services and energy systems, building operation and maintenance, occupants’ activities and behavior, and indoor environmental quality. In the past, much research focused on the first three factors.more » However, the next three human-related factors can have an influence as significant as the first three. Annex 53 employed an interdisciplinary approach, integrating building science, architectural engineering, computer modeling and simulation, and social and behavioral science to develop and apply methods to analyze and evaluate the real energy use in buildings considering the six influencing factors. Finally, outcomes from Annex 53 improved understanding and strengthen knowledge regarding the robust prediction of total energy use in buildings, enabling reliable quantitative assessment of energy-savings measures, policies, and techniques.« less
IEA EBC annex 53: Total energy use in buildings—Analysis and evaluation methods
Yoshino, Hiroshi; Hong, Tianzhen; Nord, Natasa
2017-07-18
One of the most significant barriers to achieving deep building energy efficiency is a lack of knowledge about the factors determining energy use. In fact, there is often a significant discrepancy between designed and real energy use in buildings, which is poorly understood but are believed to have more to do with the role of human behavior than building design. Building energy use is mainly influenced by six factors: climate, building envelope, building services and energy systems, building operation and maintenance, occupants’ activities and behavior, and indoor environmental quality. In the past, much research focused on the first three factors.more » However, the next three human-related factors can have an influence as significant as the first three. Annex 53 employed an interdisciplinary approach, integrating building science, architectural engineering, computer modeling and simulation, and social and behavioral science to develop and apply methods to analyze and evaluate the real energy use in buildings considering the six influencing factors. Finally, outcomes from Annex 53 improved understanding and strengthen knowledge regarding the robust prediction of total energy use in buildings, enabling reliable quantitative assessment of energy-savings measures, policies, and techniques.« less
Metabolic risk factors in mice divergently selected for BMR fed high fat and high carb diets.
Sadowska, Julita; Gębczyński, Andrzej K; Konarzewski, Marek
2017-01-01
Factors affecting contribution of spontaneous physical activity (SPA; activity associated with everyday tasks) to energy balance of humans are not well understood, as it is not clear whether low activity is related to dietary habits, precedes obesity or is a result of thereof. In particular, human studies on SPA and basal metabolic rates (BMR, accounting for >50% of human energy budget) and their associations with diet composition, metabolic thrift and obesity are equivocal. To clarify these ambiguities we used a unique animal model-mice selected for divergent BMR rates (the H-BMR and L-BMR line type) presenting a 50% between-line type difference in the primary selected trait. Males of each line type were divided into three groups and fed either a high fat, high carb or a control diet. They then spent 4 months in individual cages under conditions emulating human "sedentary lifestyle", with SPA followed every month and measurements of metabolic risk indicators (body fat mass %, blood lipid profile, fasting blood glucose levels and oxidative damage in the livers, kidneys and hearts) taken at the end of study. Mice with genetically determined high BMR assimilated more energy and had higher SPA irrespective of type of diet. H-BMR individuals were characterized by lower dry body fat mass %, better lipid profile and lower fasting blood glucose levels, but higher oxidative damage in the livers and hearts. Genetically determined high BMR may be a protective factor against diet-induced obesity and most of the metabolic syndrome indicators. Elevated spontaneous activity is correlated with high BMR, and constitutes an important factor affecting individual capability to sustain energy balance even under energy dense diets.
Silicon Schottky photovoltaic diodes for solar energy conversion
NASA Technical Reports Server (NTRS)
Anderson, W. A.
1975-01-01
Various factors in Schottky barrier solar cell fabrication are evaluated in order to improve understanding of the current flow mechanism and to isolate processing variables that improve efficiency. Results of finger design, substrate resistivity, surface finishing and activation energy studies are detailed. An increased fill factor was obtained by baking of the vacuum system to remove moisture.
Horsch, Antje; Wobmann, Marion; Kriemler, Susi; Munsch, Simone; Borloz, Sylvie; Balz, Alexandra; Marques-Vidal, Pedro; Borghini, Ayala; Puder, Jardena J
2015-02-19
Psychological stress negatively influences food intake and food choices, thereby contributing to the development of childhood obesity. Physical activity can also moderate eating behavior and influence calorie intake. However, it is unknown if acute physical activity influences food intake and overall energy balance after acute stress exposure in children. We therefore investigated the impact of acute physical activity on overall energy balance (food intake minus energy expenditure), food intake, and choice in the setting of acute social stress in normal weight (NW) and overweight/obese (OW/OB) children as well as the impact of psychological risk factors. After receiving written consent from their parents, 26 NW (BMI < 90(th) percentile) and 24 7-to 11-year-old OW (n = 5)/OB (n = 19, BMI ≥ 90(th) percentile) children were randomly allocated using computer-generated numbers (1:1, after stratification for weight status) to acute moderate physical or to sedentary activity for 30 min. Afterwards, all children were exposed to an acute social stressor. Children and their parents completed self-report questionnaires. At the end of the stressor, children were allowed to eat freely from a range of 12 different foods (6 sweet/6 salty; each of low/high caloric density). Energy balance, food intake/choice and obesity-related psychological risk factors were assessed. Lower overall energy balance (p = 0.019) and a decreased choice of low density salty foods (p < 0.001) in NW children compared with OW/OB children was found after acute moderate physical activity but not sedentary activity. Independent of their allocation, OW/OB children ate more high density salty foods (104 kcal (34 to 173), p = 0.004) following stress. They scored higher on impulsive behavior (p = 0.005), restrained eating (p < 0.001) and parental corporal punishment (p = 0.03), but these psychological factors were not related to stress-induced food intake/choice. Positive parenting tended to be related to lower intake of sweet high density food (-132 kcal, -277 to 2, p = 0.054). In the setting of stress, acute moderate physical activity can address energy balance in children, a benefit which is especially pronounced in the OW/OB. Positive parenting may act as a protective factor preventing stress-induced eating of comfort food. clinicaltrials.gov NCT01693926 The study was a pilot study of a project funded by the Swiss National Science Foundation (CRSII3_147673).
Cao, Zheng; Bowie, James U
2014-01-01
Equilibrium H/D fractionation factors have been extensively employed to qualitatively assess hydrogen bond strengths in protein structure, enzyme active sites, and DNA. It remains unclear how fractionation factors correlate with hydrogen bond free energies, however. Here we develop an empirical relationship between fractionation factors and free energy, allowing for the simple and quantitative measurement of hydrogen bond free energies. Applying our empirical relationship to prior fractionation factor studies in proteins, we find: [1] Within the folded state, backbone hydrogen bonds are only marginally stronger on average in α-helices compared to β-sheets by ∼0.2 kcal/mol. [2] Charge-stabilized hydrogen bonds are stronger than neutral hydrogen bonds by ∼2 kcal/mol on average, and can be as strong as –7 kcal/mol. [3] Changes in a few hydrogen bonds during an enzyme catalytic cycle can stabilize an intermediate state by –4.2 kcal/mol. [4] Backbone hydrogen bonds can make a large overall contribution to the energetics of conformational changes, possibly playing an important role in directing conformational changes. [5] Backbone hydrogen bonding becomes more uniform overall upon ligand binding, which may facilitate participation of the entire protein structure in events at the active site. Our energetic scale provides a simple method for further exploration of hydrogen bond free energies. PMID:24501090
Beaulieu, Kristine; Hopkins, Mark; Blundell, John; Finlayson, Graham
2017-12-28
The current obesogenic environment promotes physical inactivity and food consumption in excess of energy requirements, two important modifiable risk factors influencing energy balance. Habitual physical activity has been shown to impact not only energy expenditure, but also energy intake through mechanisms of appetite control. This review summarizes recent theory and evidence underpinning the role of physical activity in the homeostatic and non-homeostatic mechanisms controlling appetite. Energy intake along the spectrum of physical activity levels (inactive to highly active) appears to be J-shaped, with low levels of physical activity leading to dysregulated appetite and a mismatch between energy intake and expenditure. At higher levels, habitual physical activity influences homeostatic appetite control in a dual-process action by increasing the drive to eat through greater energy expenditure, but also by enhancing post-meal satiety, allowing energy intake to better match energy expenditure in response to hunger and satiety signals. There is clear presumptive evidence that physical activity energy expenditure can act as a drive (determinant) of energy intake. The influence of physical activity level on non-homeostatic appetite control is less clear, but low levels of physical activity may amplify hedonic states and behavioural traits favouring overconsumption indirectly through increased body fat. More evidence is required to understand the interaction between physical activity, appetite control and diet composition on passive overconsumption and energy balance. Furthermore, potential moderators of appetite control along the spectrum of physical activity, such as body composition, sex, and type, intensity and timing of physical activity, remain to be fully understood. Copyright © 2018 Elsevier Inc. All rights reserved.
Johnson, Perry; Bahadori, Amir; Eckerman, Keith; Lee, Choonsik; Bolch, Wesley E.
2014-01-01
A comprehensive set of photon fluence-to-dose response functions (DRFs) are presented for two radiosensitive skeletal tissues – active and total shallow marrow – within 15 and 32 bones sites, respectively, of the ICRP reference adult male. The functions were developed using fractional skeletal masses and associated electron absorbed fractions as reported for the UF hybrid adult male phantom, which in turn is based upon microCT images of trabecular spongiosa taken from a 40-year male cadaver. The new DRFs expand upon both the original set of seven functions produced in 1985, as well as a 2007 update calculated under the assumption of secondary electron escape from spongiosa. In the present study, it is assumed that photon irradiation of the skeleton will yield charged particle equilibrium across all spongiosa regions at energies exceeding 200 keV. Kerma factors for active marrow, inactive marrow, trabecular bone, and spongiosa at higher energies are calculated using the DRF algorithm setting the electron absorbed fraction for self-irradiation to unity. By comparing kerma factors and DRF functions, dose enhancement factors and mass energy-absorption coefficient (MEAC) ratios for active marrow to spongiosa were derived. These MEAC ratios compared well with those provided by the NIST Physical Reference Data Library (mean difference of 0.8%), and the dose enhancement factors for active marrow compared favorably with values calculated in the well-known study published by King and Spiers (1985) (mean absolute difference of 1.9 percentage points). Additionally, dose enhancement factors for active marrow were shown to correlate well with the shallow marrow volume fraction (R2 = 0.91). Dose enhancement factors for the total shallow marrow were also calculated for 32 bone sites PMID:21427484
USDA-ARS?s Scientific Manuscript database
Free-living measurements of 24-h total energy expenditure (TEE) and activity energy expenditure (AEE) are required to better understand the metabolic, physiological, behavioral, and environmental factors affecting energy balance and contributing to the global epidemic of childhood obesity. The spec...
Low Energy Nuclear Reaction Products at Surfaces
NASA Astrophysics Data System (ADS)
Nagel, David J.
2008-03-01
This paper examines the evidence for LENR occurring on or very near to the surface of materials. Several types of experimental indications for LENR surface reactions have been reported and will be reviewed. LENR result in two types of products, energy and the appearance of new elements. The level of instantaneous power production can be written as the product of four factors: (1) the total area of the surface on which the reactions can occur, (2) the fraction of the area that is active at any time, (3) the reaction rate, that is, the number of reactions per unit active area per second, and (4) the energy produced per reaction. Each of these factors, and their limits, are reviewed. A graphical means of relating these four factors over their wide variations has been devised. The instantaneous generation of atoms of new elements can also be written as the product of the first three factors and the new elemental mass produced per reaction. Again, a graphical means of presenting the factors and their results over many orders of magnitude has been developed.
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).
NASA Astrophysics Data System (ADS)
Kanzaki, Yoshiki; Murakami, Takashi
2018-07-01
We have developed a weathering model to comprehensively understand the determining factors of the apparent activation energy of silicate weathering in order to better estimate the silicate-weathering flux in the Precambrian. The model formulates the reaction rate of a mineral as a basis, then the elemental loss by summing the reaction rates of whole minerals, and finally the weathering flux from a given weathering profile by integrating the elemental losses along the depth of the profile. The rate expressions are formulated with physicochemical parameters relevant to weathering, including solution and atmospheric compositions. The apparent activation energies of silicate weathering are then represented by the temperature dependences of the physicochemical parameters based on the rate expressions. It was found that the interactions between individual mineral-reactions and the compositions of solution and atmosphere are necessarily accompanied by those of temperature-dependence counterparts. Indeed, the model calculates the apparent activation energy of silicate weathering as a function of the temperature dependence of atmospheric CO2 (Δ HCO2‧) . The dependence of the apparent activation energy of silicate weathering on Δ HCO2‧ may explain the empirical dependence of silicate weathering on the atmospheric composition. We further introduce a compensation law between the apparent activation energy and the pre-exponential factor to obtain the relationship between the silicate-weathering flux (FCO2), temperature and the apparent activation energy. The model calculation and the compensation law enable us to predict FCO2 as a function of temperature, once Δ HCO2‧ is given. The validity of the model is supported by agreements between the model prediction and observations of the apparent activation energy and FCO2 in the modern weathering systems. The present weathering model will be useful for the estimation of FCO2 in the Precambrian, for which Δ HCO2‧ can be deduced from the greenhouse effect of atmospheric CO2.
NASA Astrophysics Data System (ADS)
Fradi, Aniss
The ability to allocate the active power (MW) loading on transmission lines and transformers, is the basis of the "flow based" transmission allocation system developed by the North American Electric Reliability Council. In such a system, the active power flows must be allocated to each line or transformer in proportion to the active power being transmitted by each transaction imposed on the system. Currently, this is accomplished through the use of the linear Power Transfer Distribution Factors (PTDFs). Unfortunately, no linear allocation models exist for other energy transmission quantities, such as MW and MVAR losses, MVAR and MVA flows, etc. Early allocation schemes were developed to allocate MW losses due to transactions to branches in a transmission system, however they exhibited diminished accuracy, since most of them are based on linear power flow modeling of the transmission system. This thesis presents a new methodology to calculate Energy Transaction Allocation factors (ETA factors, or eta factors), using the well-known process of integration of a first derivative function, as well as consistent and well-established mathematical and AC power flow models. The factors give a highly accurate allocation of any non-linear system quantity to transactions placed on the transmission system. The thesis also extends the new ETA factors calculation procedure to restructure a new economic dispatch scheme where multiple sets of generators are economically dispatched to meet their corresponding load and their share of the losses.
Weiste, Christoph; Pedrotti, Lorenzo; Muralidhara, Prathibha; Ljung, Karin; Dröge-Laser, Wolfgang
2017-01-01
Plants have to tightly control their energy homeostasis to ensure survival and fitness under constantly changing environmental conditions. Thus, it is stringently required that energy-consuming stress-adaptation and growth-related processes are dynamically tuned according to the prevailing energy availability. The evolutionary conserved SUCROSE NON-FERMENTING1 RELATED KINASES1 (SnRK1) and the downstream group C/S1 basic leucine zipper (bZIP) transcription factors (TFs) are well-characterised central players in plants’ low-energy management. Nevertheless, mechanistic insights into plant growth control under energy deprived conditions remains largely elusive. In this work, we disclose the novel function of the low-energy activated group S1 bZIP11-related TFs as regulators of auxin-mediated primary root growth. Whereas transgenic gain-of-function approaches of these bZIPs interfere with the activity of the root apical meristem and result in root growth repression, root growth of loss-of-function plants show a pronounced insensitivity to low-energy conditions. Based on ensuing molecular and biochemical analyses, we propose a mechanistic model, in which bZIP11-related TFs gain control over the root meristem by directly activating IAA3/SHY2 transcription. IAA3/SHY2 is a pivotal negative regulator of root growth, which has been demonstrated to efficiently repress transcription of major auxin transport facilitators of the PIN-FORMED (PIN) gene family, thereby restricting polar auxin transport to the root tip and in consequence auxin-driven primary root growth. Taken together, our results disclose the central low-energy activated SnRK1-C/S1-bZIP signalling module as gateway to integrate information on the plant’s energy status into root meristem control, thereby balancing plant growth and cellular energy resources. PMID:28158182
Weiste, Christoph; Pedrotti, Lorenzo; Selvanayagam, Jebasingh; Muralidhara, Prathibha; Fröschel, Christian; Novák, Ondřej; Ljung, Karin; Hanson, Johannes; Dröge-Laser, Wolfgang
2017-02-01
Plants have to tightly control their energy homeostasis to ensure survival and fitness under constantly changing environmental conditions. Thus, it is stringently required that energy-consuming stress-adaptation and growth-related processes are dynamically tuned according to the prevailing energy availability. The evolutionary conserved SUCROSE NON-FERMENTING1 RELATED KINASES1 (SnRK1) and the downstream group C/S1 basic leucine zipper (bZIP) transcription factors (TFs) are well-characterised central players in plants' low-energy management. Nevertheless, mechanistic insights into plant growth control under energy deprived conditions remains largely elusive. In this work, we disclose the novel function of the low-energy activated group S1 bZIP11-related TFs as regulators of auxin-mediated primary root growth. Whereas transgenic gain-of-function approaches of these bZIPs interfere with the activity of the root apical meristem and result in root growth repression, root growth of loss-of-function plants show a pronounced insensitivity to low-energy conditions. Based on ensuing molecular and biochemical analyses, we propose a mechanistic model, in which bZIP11-related TFs gain control over the root meristem by directly activating IAA3/SHY2 transcription. IAA3/SHY2 is a pivotal negative regulator of root growth, which has been demonstrated to efficiently repress transcription of major auxin transport facilitators of the PIN-FORMED (PIN) gene family, thereby restricting polar auxin transport to the root tip and in consequence auxin-driven primary root growth. Taken together, our results disclose the central low-energy activated SnRK1-C/S1-bZIP signalling module as gateway to integrate information on the plant's energy status into root meristem control, thereby balancing plant growth and cellular energy resources.
Comparison of Activity Determination of Radium 226 in FUSRAP Soil using Various Energy Lines - 12299
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tucker, Brian; Donakowski, Jough; Hays, David
2012-07-01
Gamma spectroscopy is used at the Formerly Utilized Sites Remedial Action Program (FUSRAP) Maywood Superfund Site as the primary radioanalytical tool for quantization of activities of the radionuclides of concern in site soil. When selecting energy lines in gamma spectroscopy, a number of factors are considered including assumptions concerning secondary equilibrium, interferences, and the strength of the lines. The case of the Maywood radionuclide of concern radium-226 (Ra-226) is considered in this paper. At the FUSRAP Maywood Superfund Site, one of the daughters produced from radioactive decay of Ra-226, lead-214 (Pb- 214), is used to quantitate Ra-226. Another Ra-226 daughter,more » bismuth-214 (Bi-214), also may be used to quantitate Ra-226. In this paper, a comparison of Ra-226 to Pb-214 activities and Ra-226 to Bi-214 activities, obtained using gamma spectrometry for a large number of soil samples, was performed. The Pb-214, Bi-214, and Ra-226 activities were quantitated using the 352 kilo electron volt (keV), 609 keV, and 186 keV lines, respectively. The comparisons were made after correcting the Ra-226 activities by a factor of 0.571 and both ignoring and accounting for the contribution of a U-235 interfering line to the Ra-226 line. For the Pb-214 and Bi-214 activities, a mean in-growth factor was employed. The gamma spectrometer was calibrated for efficiency and energy using a mixed gamma standard and an energy range of 59 keV to 1830 keV. The authors expect other sites with Ra-226 contamination in soil may benefit from the discussions and points in this paper. Proper use of correction factors and comparison of the data from three different gamma-emitting radionuclides revealed agreement with expectations and provided confidence that using such correction factors generates quality data. The results indicate that if contamination is low level and due to NORM, the Ra-226 can be measured directly if corrected to subtract the contribution from U-235. If there is any indication that technologically enhanced uranium may be present, the preferred measurement approach for quantitation of Ra-226 activity is detection of one of the Ra-226 daughters, Pb-214 or Bi-214, using a correction factor obtained from an in-growth curve. The results also show that the adjusted Ra-226 results compare very well with both the Pb-214 and Bi-214 results obtained using an in-growth curve correction factor. (authors)« less
Cellular Links between Neuronal Activity and Energy Homeostasis.
Shetty, Pavan K; Galeffi, Francesca; Turner, Dennis A
2012-01-01
Neuronal activity, astrocytic responses to this activity, and energy homeostasis are linked together during baseline, conscious conditions, and short-term rapid activation (as occurs with sensory or motor function). Nervous system energy homeostasis also varies during long-term physiological conditions (i.e., development and aging) and with adaptation to pathological conditions, such as ischemia or low glucose. Neuronal activation requires increased metabolism (i.e., ATP generation) which leads initially to substrate depletion, induction of a variety of signals for enhanced astrocytic function, and increased local blood flow and substrate delivery. Energy generation (particularly in mitochondria) and use during ATP hydrolysis also lead to considerable heat generation. The local increases in blood flow noted following neuronal activation can both enhance local substrate delivery but also provides a heat sink to help cool the brain and removal of waste by-products. In this review we highlight the interactions between short-term neuronal activity and energy metabolism with an emphasis on signals and factors regulating astrocyte function and substrate supply.
Wang, Rui; Chang, Yong-sheng; Fang, Fu-de
2009-12-01
Peroxisome proliferator-activated receptor gamma coactivator 1 (PGC1) family is highly expressed in tissues with high energy metabolism. They coactivate transcription factors in regulating genes engaged in processes such as gluconeogenesis, adipose beta-oxydation, lipoprotein synthesis and secretion, mitochondrial biogenesis, and oxidative metabolism. Protein conformation studies demonstrated that they lack DNA binding domains and act as coactivators through physical interaction with transcription factors. PGC1 activity is regulated at transcription level or by multiple covalent chemical modifications such as phosphorylation, methylation and acetylation/deacetylation. Abnormal expression of PGC1 coactivators usually is closely correlated with diseases such as diabetes, obesity, hyperglycemia, hyperlipemia, and arterial and brain neuron necrosis diseases.
Chen, Nanwei; Ren, Jie; Ye, Ziwei; Xu, Qizhi; Liu, Jingyong; Sun, Shuiyu
2016-12-01
This study was carried out to investigate the kinetics of coffee industrial residue (CIR) pyrolysis, the effect of pyrolysis factors on yield of bio-oil component and components separation of bio-oil. The kinetics of CIR pyrolysis was analyzed using distributed activation energy model (DAEM), based on the experiments in thermogravimetric analyzer (TGA), and it indicated that the average of activation energy (E) is 187.86kJ·mol -1 . The bio-oils were prepared from CIR pyrolysis in vacuum tube furnace, and its components were determined by gas chromatography/mass spectrometry (GC-MS). Among pyrolysis factors, pyrolysis temperature is the most influential factor on components yield of bio-oil, directly concerned with the volatilization and yield of components (palmitic acid, linoleic acid, oleic acid, octadecanoic acid and caffeine). Furthermore, a new method (sequencing temperature-raising pyrolysis) was put forward and applied to the components separation of bio-oil. Based on experiments, a solution of components separation of bio-oil was come out. Copyright © 2016 Elsevier Ltd. All rights reserved.
Loss of pericyte smoothened activity in mice with genetic deficiency of leptin.
Xie, Guanhua; Swiderska-Syn, Marzena; Jewell, Mark L; Machado, Mariana Verdelho; Michelotti, Gregory A; Premont, Richard T; Diehl, Anna Mae
2017-04-20
Obesity is associated with multiple diseases, but it is unclear how obesity promotes progressive tissue damage. Recovery from injury requires repair, an energy-expensive process that is coupled to energy availability at the cellular level. The satiety factor, leptin, is a key component of the sensor that matches cellular energy utilization to available energy supplies. Leptin deficiency signals energy depletion, whereas activating the Hedgehog pathway drives energy-consuming activities. Tissue repair is impaired in mice that are obese due to genetic leptin deficiency. Tissue repair is also blocked and obesity enhanced by inhibiting Hedgehog activity. We evaluated the hypothesis that loss of leptin silences Hedgehog signaling in pericytes, multipotent leptin-target cells that regulate a variety of responses that are often defective in obesity, including tissue repair and adipocyte differentiation. We found that pericytes from liver and white adipose tissue require leptin to maintain expression of the Hedgehog co-receptor, Smoothened, which controls the activities of Hedgehog-regulated Gli transcription factors that orchestrate gene expression programs that dictate pericyte fate. Smoothened suppression prevents liver pericytes from being reprogrammed into myofibroblasts, but stimulates adipose-derived pericytes to become white adipocytes. Progressive Hedgehog pathway decay promotes senescence in leptin-deficient liver pericytes, which, in turn, generate paracrine signals that cause neighboring hepatocytes to become fatty and less proliferative, enhancing vulnerability to liver damage. Leptin-responsive pericytes evaluate energy availability to inform tissue construction by modulating Hedgehog pathway activity and thus, are at the root of progressive obesity-related tissue pathology. Leptin deficiency inhibits Hedgehog signaling in pericytes to trigger a pericytopathy that promotes both adiposity and obesity-related tissue damage.
Transportation energy data book
DOT National Transportation Integrated Search
1999-09-01
This report presents statistics that characterize transportation activities and data on other factors that affect transportation energy use. The 12 chapters of the 19th edition of the Data Book focus on various aspects of the transportation industry:...
Monthly energy review, August 1998
DOE Office of Scientific and Technical Information (OSTI.GOV)
NONE
The Monthly Energy Review (MER) presents an overview of the Energy Information Administration`s recent monthly energy statistics. The statistics cover the major activities of US production, consumption, trade, stocks, and prices for petroleum, natural gas, coal, electricity, and nuclear energy. Also included are international energy and thermal and metric conversion factors. The MER is intended for use by Members of Congress, Federal and State agencies, energy analysts, and the general public. 37 figs., 73 tabs.
Multi-factor energy price models and exotic derivatives pricing
NASA Astrophysics Data System (ADS)
Hikspoors, Samuel
The high pace at which many of the world's energy markets have gradually been opened to competition have generated a significant amount of new financial activity. Both academicians and practitioners alike recently started to develop the tools of energy derivatives pricing/hedging as a quantitative topic of its own. The energy contract structures as well as their underlying asset properties set the energy risk management industry apart from its more standard equity and fixed income counterparts. This thesis naturally contributes to these broad market developments in participating to the advances of the mathematical tools aiming at a better theory of energy contingent claim pricing/hedging. We propose many realistic two-factor and three-factor models for spot and forward price processes that generalize some well known and standard modeling assumptions. We develop the associated pricing methodologies and propose stable calibration algorithms that motivate the application of the relevant modeling schemes.
Calculation of self–shielding factor for neutron activation experiments using GEANT4 and MCNP
DOE Office of Scientific and Technical Information (OSTI.GOV)
Romero–Barrientos, Jaime, E-mail: jaromero@ing.uchile.cl; Universidad de Chile, DFI, Facultad de Ciencias Físicas Y Matemáticas, Avenida Blanco Encalada 2008, Santiago; Molina, F.
2016-07-07
The neutron self–shielding factor G as a function of the neutron energy was obtained for 14 pure metallic samples in 1000 isolethargic energy bins from 1·10{sup −5}eV to 2·10{sup 7}eV using Monte Carlo simulations in GEANT4 and MCNP6. The comparison of these two Monte Carlo codes shows small differences in the final self–shielding factor mostly due to the different cross section databases that each program uses.
Energy Savings Lifetimes and Persistence
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hoffman, Ian M.; Schiller, Steven R.; Todd, Annika
2016-02-01
This technical brief explains the concepts of energy savings lifetimes and savings persistence and discusses how program administrators use these factors to calculate savings for efficiency measures, programs and portfolios. Savings lifetime is the length of time that one or more energy efficiency measures or activities save energy, and savings persistence is the change in savings throughout the functional life of a given efficiency measure or activity. Savings lifetimes are essential for assessing the lifecycle benefits and cost effectiveness of efficiency activities and for forecasting loads in resource planning. The brief also provides estimates of savings lifetimes derived from amore » national collection of costs and savings for electric efficiency programs and portfolios.« less
Determination of the efficiency of commercially available dose calibrators for beta-emitters.
Valley, Jean-François; Bulling, Shelley; Leresche, Michel; Wastiel, Claude
2003-03-01
The goals of this investigation are to determine whether commercially available dose calibrators can be used to measure the activity of beta-emitting radionuclides used in pain palliation and to establish whether manufacturer-supplied calibration factors are appropriate for this purpose. Six types of commercially available dose calibrators were studied. Dose calibrator response was controlled for 5 gamma-emitters used for calibration or typically encountered in routine use. For the 4 most commonly used beta-emitters ((32)P, (90)Sr, (90)Y, and (169)Er) dose calibrator efficiency was determined in the syringe geometry used for clinical applications. Efficiency of the calibrators was also measured for (153)Sm and (186)Re, 2 beta-emitters with significant gamma-contributions. Source activities were traceable to national standards. All calibrators measured gamma-emitters with a precision of +/-10%, in compliance with Swiss regulatory requirements. For beta-emitters, dose calibrator intrinsic efficiency depends strongly on the maximal energy of the beta-spectrum and is notably low for (169)Er. Manufacturer-supplied calibration factors give accurate results for beta-emitters with maximal beta-energy in the middle-energy range (1 MeV) but are not appropriate for use with low-energy ((169)Er) or high-energy ((90)Y) beta-emitters. beta-emitters with significant gamma-contributions behave like gamma-emitters. Commercially available dose calibrators have an intrinsic efficiency that is sufficient for the measurement of beta-emitters, including beta-emitters with a low maximum beta-energy. Manufacturer-supplied calibration factors are reliable for gamma-emitters and beta-emitters in the middle-energy range. For low- and high-energy beta-emitters, the use of manufacturer-supplied calibration factors introduces significant measurement inaccuracy.
State energy data report: Statistical tables and technical documentation 1960 through 1979
NASA Astrophysics Data System (ADS)
1981-09-01
All the data of the State Energy Data System (SEDS) is given. The data is used to estimate annual energy consumption by principal energy sources (coal, natural gas, petroleum, electricity), by major end-use sectors (residential, commercial, industrial, transportation, and electric utilities), and by state (50 states, the District of Columbia, and the United States). Data is organized alphabetically by energy source (fuel), by end-use sector or energy activity, by type of data and by state. Twenty data values are associated with each fuel-sector-type state grouping representing positionally the years 1960 through 1979. Data values in the file are expressed either as physical units, British thermal units, physical to Btu conversion factors or share factors.
Parekh, Niyati; Lin, Yong; Marcella, Stephen; Kant, Ashima K.; Lu-Yao, Grace
2010-01-01
Studies suggest inverse associations between obesity and PSA. However, there is little evidence whether factors related to obesity including lifestyle (diet and physical activity) and physiological factors (insulin resistance and metabolic syndrome), influence PSA. We used dietary, physical activity and serum PSA, insulin, glucose, and lipid data for men 40+ years, from the National Health and Nutrition Examination Survey (2001-2004; n=2,548). Energy, fat and carbohydrate intakes were estimated from a 24-hour dietary recall. Men were considered as having metabolic syndrome based on the Adult Treatment Panel III criteria. Leisure-time physical activity and doctor-diagnosed hypertension were self-reported. Body mass index (BMI) was calculated from measured weight and height. We computed geometric mean PSA (ng/ml), adjusted for age, race and BMI, by tertile of energy, fat and carbohydrate intake, and level of physical activity, and among men with and without insulin resistance and metabolic syndrome, in the whole population, and by race. The geometric mean PSA (95%CI) among men in the lowest tertile of energy was 1.05 (0.97-1.1), relative to 0.85(0.8-0.9) in the highest tertile (p=0.0002) in the whole population. PSA concentrations were lower among overweight men with higher versus lower energy intake (p=0.001). PSA concentrations in men with insulin resistance was lower (0.87(0.8-0.9)), relative to men without insulin resistance (0.98(0.9-1.1)), p=0.04. All associations were in similar directions within racial subgroups. No associations were observed between the other lifestyle and physiological factors. Additional studies are required to confirm these results and to investigate the potential mechanisms that may explain these relationships. PMID:18768517
Active commuting and sociodemographic factors among university students in Spain.
Molina-García, Javier; Sallis, James F; Castillo, Isabel
2014-02-01
Commuting to university represents an opportunity to incorporate physical activity (walking or biking) into students' daily routines. There are few studies that analyze patterns of transport in university populations. This cross-sectional study estimated energy expenditure from active commuting to university (ACU) and examined sociodemographic differences in findings. The sample included 518 students with a mean age of 22.4 years (59.7% female) from 2 urban universities in Valencia, Spain. Time spent in each mode of transport to university and sociodemographic factors was assessed by self-report. Nearly 35% of the students reported walking or biking as their main mode of transport. ACU (min/wk) were highest for walkers (168) and cyclists (137) and lowest for motorbike riders (0.0) and car drivers (16). Public transport users, younger students, low socioeconomic status students, and those living ≤ 2 km from the university had higher energy expenditure from active commuting than comparison groups. Biking was highest among those living 2-5 km from the university. Our findings suggest that active commuting and public transit use generated substantial weekly energy expenditure, contributed to meeting physical activity recommendations, and may aid in obesity prevention.
NASA Astrophysics Data System (ADS)
Mitri, F. G.
2017-11-01
Active cloaking in its basic form requires that the extinction cross-section (or energy efficiency) from a radiating body vanishes. In this analysis, this physical effect is demonstrated for an active cylindrically radiating acoustic source in a non-viscous fluid, undergoing periodic axisymmetric harmonic vibrations near a rigid corner (i.e., quarter-space). The rigorous multipole expansion method in cylindrical coordinates, the method of images, and the addition theorem of cylindrical wave functions are used to derive closed-form mathematical expressions for the radiating, amplification, and extinction cross-sections of the active source. Numerical computations are performed assuming monopole and dipole modal oscillations of the circular source. The results reveal some of the situations where the extinction energy efficiency factor of the active source vanishes depending on its size and location with respect to the rigid corner, thus, achieving total invisibility. Moreover, the extinction energy efficiency factor varies between positive or negative values. These effects also occur for higher-order modal oscillations of the active source. The results find potential applications in the development of acoustic cloaking devices and invisibility in underwater acoustics or other areas.
NASA Astrophysics Data System (ADS)
Dolomatov, M. Yu.; Kovaleva, E. A.; Khamidullina, D. A.
2018-05-01
An approach that allows the calculation of dynamic viscosity for liquid hydrocarbons from quantum (ionization energies) and molecular (Wiener topological indices) parameters is proposed. A physical relationship is revealed between ionization and the energies of viscous flow activation. This relationship is due to the contribution from the dispersion component of Van der Waals forces to intermolecular interaction. A two-parameter dependence of the energy of viscous flow activation, energy of ionization, and Wiener topological indices is obtained. The dynamic viscosities of liquid hydrocarbons can be calculated from the kinetic compensation effect of dynamic viscosity, which indicates a relationship between the energy of activation and the Arrhenius pre-exponental factor of the Frenkel-Eyring hole model. Calculation results are confirmed through statistical processing of the experimental data.
Results on the neutron energy distribution measurements at the RECH-1 Chilean nuclear reactor
DOE Office of Scientific and Technical Information (OSTI.GOV)
Aguilera, P., E-mail: paguilera87@gmail.com; Romero-Barrientos, J.; Universidad de Chile, Dpto. de Física, Facultad de Ciencias, Las Palmeras 3425, Nuñoa, Santiago
2016-07-07
Neutron activations experiments has been perform at the RECH-1 Chilean Nuclear Reactor to measure its neutron flux energy distribution. Samples of pure elements was activated to obtain the saturation activities for each reaction. Using - ray spectroscopy we identify and measure the activity of the reaction product nuclei, obtaining the saturation activities of 20 reactions. GEANT4 and MCNP was used to compute the self shielding factor to correct the cross section for each element. With the Expectation-Maximization algorithm (EM) we were able to unfold the neutron flux energy distribution at dry tube position, near the RECH-1 core. In this work,more » we present the unfolding results using the EM algorithm.« less
Schnier, Paul D.; Price, William D.; Jockusch, Rebecca A.
2005-01-01
Blackbody infrared radiative dissociation (BIRD) spectra of singly and doubly protonated bradykinin and its analogues are measured in a Fourier-transform mass spectrometer. Rate constants for dissociation are measured as a function of temperature with reaction delays up to 600 s. From these data, Arrhenius activation parameters in the zero-pressure limit are obtained. The activation parameters and dissociation products for the singly protonated ions are highly sensitive to small changes in ion structure. The Arrhenius activation energy (Ea) and pre-exponential (or frequency factor, A) of the singly protonated ions investigated here range from 0.6 to 1.4 eV and 105 to 1012 s−1, respectively. For bradykinin and its analogues differing by modification of the residues between the two arginine groups on either end of the molecule, the singly and doubly protonated ions have average activation energies of 1.2 and 0.8 eV, respectively, and average A values of 108 and 1012 s−1, respectively, i.e., the presence of a second charge reduces the activation energy by 0.4 eV and decreases the A value by a factor of 104. This demonstrates that the presence of a second charge can dramatically influence the dissociation dynamics of these ions. The doubly protonated methyl ester of bradykinin has an Ea of 0.82 eV, comparable to the value of 0.84 eV for bradykinin itself. However, this value is 0.21 ± 0.08 eV greater than that of singly protonated methyl ester of bradykinin, indicating that the Coulomb repulsion is not the most significant factor in the activation energy of this ion. Both singly and doubly protonated Lys-bradykinin ions have higher activation energies than the corresponding bradykinin ions indicating that the addition of a basic residue stabilizes these ions with respect to dissociation. Methylation of the carboxylic acid group of the C-terminus reduces the Ea of bradykinin from 1.3 to 0.6 eV and the A factor from 1012 to 105 s−1. This modification also dramatically changes the dissociation products. Similar results are observed for [Ala6]-bradykinin and its methyl ester. These results, in combination with others presented here, provide experimental evidence that the most stable form of singly protonated bradykinin is a salt-bridge structure. PMID:16525512
Kinetic study of solid waste pyrolysis using distributed activation energy model.
Bhavanam, Anjireddy; Sastry, R C
2015-02-01
The pyrolysis characteristics of municipal solid waste, agricultural residues such as ground nut shell, cotton husk and their blends are investigated using non-isothermal thermogravimetric analysis (TGA) with in a temperature range of 30-900 °C at different heating rates of 10 °C, 30 °C and 50 °C/min in inert atmosphere. From the thermograms obtained from TGA, it is observed that the maximum rate of degradation occurred in the second stage of the pyrolysis process for all the solid wastes. The distributed activation energy model (DAEM) is used to study the pyrolysis kinetics of the solid wastes. The kinetic parameters E (activation energy), k0 (frequency factor) are calculated from this model. It is found that the range of activation energies for agricultural residues are lower than the municipal solid waste. The activation energies for the municipal solid waste pyrolysis process drastically decreased with addition of agricultural residues. The proposed DAEM is successfully validated with TGA experimental data. Copyright © 2014 Elsevier Ltd. All rights reserved.
A GIS based model for active transportation in the built environment
NASA Astrophysics Data System (ADS)
Addison, Veronica Marie Medina
Obesity and physical inactivity have been major risk factors associated with morbidity and mortality in the United States. Recently, obesity and physical inactivity have been on the rise. Determining connections between this trend and the environment could lead to a built environment that is conducive to healthy, active people. In my previous research, I have studied the built environment and its connection to health. For my dissertation, I build on this fundamental work by incorporating energy, specifically by studying the built environment and its connection to energy expenditures. This research models the built environment and combines this with human energy expenditure information in order to provide a planning tool that allows an individual to actively address health issues, particularly obesity. This research focuses on the design and development of an internet based model that enables individuals to understand their own energy expenditures in relation to their environment. The model will work to find the energy consumed by an individual in their navigation through campus. This is accomplished by using Geographic Information Systems (GIS) to model the campus and using it as the basis for calculating energy expended through active transportation. Using GIS to create the model allows for the incorporation of built environment factors such as elevation and energy expenditures in relation to physical exertion rate. This research will contribute to the long-term solution to the obesity epidemic by creating healthy communities through smart growth and sustainable design. This research provides users with a tool to use in their current environment for their personal and community well being.
Priya, Anusha; Johar, Kaid; Wong-Riley, Margaret T T
2013-01-01
Neuronal activity and energy metabolism are tightly coupled processes. Previously, we found that nuclear respiratory factor 1 (NRF-1) transcriptionally co-regulates energy metabolism and neuronal activity by regulating all 13 subunits of the critical energy generating enzyme, cytochrome c oxidase (COX), as well as N-methyl-d-aspartate (NMDA) receptor subunits 1 and 2B, GluN1 (Grin1) and GluN2B (Grin2b). We also found that another transcription factor, nuclear respiratory factor 2 (NRF-2 or GA-binding protein) regulates all subunits of COX as well. The goal of the present study was to test our hypothesis that NRF-2 also regulates specific subunits of NMDA receptors, and that it functions with NRF-1 via one of three mechanisms: complementary, concurrent and parallel, or a combination of complementary and concurrent/parallel. By means of multiple approaches, including in silico analysis, electrophoretic mobility shift and supershift assays, in vivo chromatin immunoprecipitation of mouse neuroblastoma cells and rat visual cortical tissue, promoter mutations, real-time quantitative PCR, and western blot analysis, NRF-2 was found to functionally regulate Grin1 and Grin2b genes, but not any other NMDA subunit genes. Grin1 and Grin2b transcripts were up-regulated by depolarizing KCl, but silencing of NRF-2 prevented this up-regulation. On the other hand, over-expression of NRF-2 rescued the down-regulation of these subunits by the impulse blocker TTX. NRF-2 binding sites on Grin1 and Grin2b are conserved among species. Our data indicate that NRF-2 and NRF-1 operate in a concurrent and parallel manner in mediating the tight coupling between energy metabolism and neuronal activity at the molecular level. Copyright © 2012 Elsevier B.V. All rights reserved.
Woon, Fui Chee; Chin, Yit Siew; Mohd Nasir, Mohd Taib
2015-01-01
This paper investigates the association between behavioural factors and BMI-for-age among early adolescents (10-11 years old) in Hulu Langat district, Selangor. This cross-sectional study was conducted among 333 primary school students. Body weight and height of the students were measured and their BMI-for-age was calculated. Eating behaviours, energy intake, energy expenditure, physical activity, and screen time were assessed using the Eating Behaviours Questionnaire and a 2-day dietary and physical activity recall, respectively. Data were analysed using multiple linear regression analysis. The prevalence of overweight and obesity (28.2%) was about twice the prevalence of thinness (11.1%). The mean energy intake and energy expenditure of the students was 1772±441kcal/day and 1705±331kcal/day, respectively. Three in five of the students (60.1%) skipped at least one meal and 98.2% snacked between meals daily. A majority of them (55.3%) were sedentary. Low energy intake (p<0.05) and low energy expenditure (p<0.05) were associated with high BMI-for-age. Energy expenditure (β=-0.033) and energy intake (β=-0.090) significantly explained 65.1% of the variances in BMI-for-age (F=119.170, p<0.05). These findings suggested that promoting healthy eating and active lifestyle should be targeted in the prevention and management of obesity among early adolescents. Copyright © 2014 Asian Oceanian Association for the Study of Obesity. Published by Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Papelniuk, Oksana
2017-10-01
The author studies innovative activity of enterprises and carries out the classification of conditions and factors of construction enterprises’ innovative activity, and conducts systematization of specific features of this innovative activity. On the basis of statistical data on structure and dynamics of innovations the author carries out the research with the use of methods of economic-mathematical modelling in order to offer the approach which will allow construction enterprises to define the directions of innovative activity for achievement of a resource-saving and energy efficiency in construction sector.
Tagliente, Irene; Solvoll, Terje; Trieste, Leopoldo; De Cecco, Carlo N; Murgia, Fabrizio; Bella, Sergio
2016-09-14
Obesity is one of the biggest drivers of preventable chronic diseases and healthcare costs in Worldwide. Different prevention activities are suggested. By monitoring daily energy expenditure (EE) could be possible make personalized diets and programming physical activity. In this, physical inactivity is one of the most important public health problems. Some studies refer the effort of the international community in promoting physical activities. Physical activity can be promoted only by increasing citizens' empowerment on taking care of their health, and it passes from the improving of individual information. Technology can offer solutions and metrics for monitoring and measuring daily activity by interacting with individuals, sharing information and feedbacks. In this study we review indicators of total energy expenditure and weaknesses of available devices in assessing these parameters. Literature review and technology testing EuNetHta core model. For the clinical aspects, it is fundamental to take into account all the factor that can influence the personal energy expenditure as: heart rate, blood pressure and thermoregulation (influenced by the body temperature). In this study we focused the attention on the importance of tools to encourage the physical activity. We made an analysis of the factor that can influence the right analysis of energy expenditure and at the same time the energy regime. A punctual monitoring of the exercise regime could be helpful in Telemedicine application as Telemonitorig. More study are needed to value the impact of physical activity tracker in Telemonitorig protocols. On the assessment of the energy expenditure, critical issues are related to the physiological data acquisition. Sensors connected with mobile devices could be important tools for disease prevention and interventions affecting health behaviors. New devices applications are potential useful for telemedicine assistance, but security of data and the related communication protocol limits should be taking into account.
Pierre, Jon Paul; Wolaver, Brad D; Labay, Benjamin J; LaDuc, Travis J; Duran, Charles M; Ryberg, Wade A; Hibbitts, Toby J; Andrews, John R
2018-05-01
Recent research assessed how hydrocarbon and wind energy expansion has altered the North American landscape. Less understood, however, is how this energy development compares to other anthropogenic land use changes. Texas leads U.S. hydrocarbon production and wind power generation and has a rapidly expanding population. Thus, for ~47% of Texas (~324,000 km 2 ), we mapped the 2014 footprint of energy activities (~665,000 oil and gas wells, ~5700 wind turbines, ~237,000 km oil and gas pipelines, and ~2000 km electrical transmission lines). We compared the footprint of energy development to non-energy-related activities (agriculture, roads, urbanization) and found direct landscape alteration from all factors affects ~23% of the study area (~76,000 km 2 ), led by agriculture (~16%; ~52,882 km 2 ). Oil and gas activities altered <1% of the study area (2081 km 2 ), with 838 km 2 from pipelines and 1242 km 2 from well pad construction-and that the median Eagle Ford well pad is 7.7 times larger than that in the Permian Basin (16,200 vs. 2100 m 2 ). Wind energy occupied <0.01% (~24 km 2 ), with ~14 km 2 from turbine pads and ~10 km 2 from power transmission lines. We found that edge effects of widely-distributed energy infrastructure caused more indirect landscape alteration than larger, more concentrated urbanization and agriculture. This study presents a novel technique to quantify and compare anthropogenic activities causing both direct and indirect landscape alteration. We illustrate this landscape-mapping framework in Texas for the Spot-tailed Earless Lizard (Holbrookia lacerata); however, the approach can be applied to a range of species in developing regions globally.
Saker, Meriem; Merzouk, Hafida; Merzouk, Sid A; Ahmed, Samira Baba; Narce, Michel
2011-01-01
ABSTRACT Background: Obesity has reached epidemic proportions world-wide. Its risk factors are poorly studied, especially among children in developing countries such as Algeria. Objectives: The purpose of this study was therefore to determine the prevalence and risk factors of obesity in Algerian schoolchildren 6 to 8 years aged by conducting a school-site retrospective cohort study in Tlemcen Department (western Algeria). Material and Mthods: From 2008 to 2010, socio-demographic characteristics, body mass index (BMI), physical activity categories, lifestyle and nutritional habits of 1520 children (839 boys and 681 girls), at entrance into primary school, were recorded using a self-administered questionnaire. Results: Among the 1520 participants, 99 (6.5%) were obese. Birthweight ≤ 2.5 kg and ≥ 4 kg, early introduction of solid foods and low physical activity were significantly associated with obesity (p<0.001). Additionally, mother's and grandmother's BMI ≥30 kg/m2, fewer children in the household, higher parental education, household income and the presence of familial obesity may predispose significantly to childhood obesity (p<0.001). Furthermore, child's BMI was significant positively correlated with total energy, fat and saturated fatty acid (SFA) intakes (p<0.01). Mother's and grandmother's BMI were significant positively correlated with child total energy, fat and SFA intakes. Physical activity score was significant negatively correlated with child total energy, fat and SFA (p<0.01) intakes in obese children. Conclusions: Mother's and grandmother's obesity, excess energy and fat intakes and low physical activity are the strong predictors of childhood obesity in Algeria. Preventive measures should focus on the promotion of physical activity and maternal and children nutritional education. PMID:22205890
Miyake, Masato; Nomura, Akitoshi; Ogura, Atsushi; Takehana, Kenji; Kitahara, Yoshihiro; Takahara, Kazuna; Tsugawa, Kazue; Miyamoto, Chinobu; Miura, Naoko; Sato, Ryosuke; Kurahashi, Kiyoe; Harding, Heather P; Oyadomari, Miho; Ron, David; Oyadomari, Seiichi
2016-02-01
The eukaryotic translation initiation factor 2α (eIF2α) phosphorylation-dependent integrated stress response (ISR), a component of the unfolded protein response, has long been known to regulate intermediary metabolism, but the details are poorly worked out. We report that profiling of mRNAs of transgenic mice harboring a ligand-activated skeletal muscle-specific derivative of the eIF2α protein kinase R-like ER kinase revealed the expected up-regulation of genes involved in amino acid biosynthesis and transport but also uncovered the induced expression and secretion of a myokine, fibroblast growth factor 21 (FGF21), that stimulates energy consumption and prevents obesity. The link between the ISR and FGF21 expression was further reinforced by the identification of a small-molecule ISR activator that promoted Fgf21 expression in cell-based screens and by implication of the ISR-inducible activating transcription factor 4 in the process. Our findings establish that eIF2α phosphorylation regulates not only cell-autonomous proteostasis and amino acid metabolism, but also affects non-cell-autonomous metabolic regulation by induced expression of a potent myokine. © FASEB.
Ye, Naihao; Li, Demao; Chen, Limei; Zhang, Xiaowen; Xu, Dong
2010-01-01
Seaweed has attracted considerable attention as a potential biofuel feedstock. The pyrolytic and kinetic characteristics of maize straw and the seaweed Ulva pertusa were studied and compared using heating rates of 10, 30 and 50°C min−1 under an inert atmosphere. The activation energy, and pre-exponential factors were calculated by the Flynn-Wall-Ozawa (FWO), Kissinger-Akahira-Sunose (KAS) and Popescu methods. The kinetic mechanism was deduced by the Popescu method. The results indicate that there are three stages to the pyrolysis; dehydration, primary devolatilization and residual decomposition. There were significant differences in average activation energy, thermal stability, final residuals and reaction rates between the two materials. The primary devolatilization stage of U. pertusa can be described by the Avramic-Erofeev equation (n = 3), whereas that of maize straw can be described by the Mampel Power Law (n = 2). The average activation energy of maize straw and U. pertusa were 153.0 and 148.7 KJ mol−1, respectively. The pyrolysis process of U.pertusa would be easier than maize straw. And co-firing of the two biomass may be require less external heat input and improve process stability. There were minor kinetic compensation effects between the pre-exponential factors and the activation energy. PMID:20844751
Emissions from oil and gas operations in the United States and their air quality implications.
Allen, David T
2016-06-01
The energy supply infrastructure in the United States has been changing dramatically over the past decade. Increased production of oil and natural gas, particularly from shale resources using horizontal drilling and hydraulic fracturing, made the United States the world's largest producer of oil and natural gas in 2014. This review examines air quality impacts, specifically, changes in greenhouse gas, criteria air pollutant, and air toxics emissions from oil and gas production activities that are a result of these changes in energy supplies and use. National emission inventories indicate that volatile organic compound (VOC) and nitrogen oxide (NOx) emissions from oil and gas supply chains in the United States have been increasing significantly, whereas emission inventories for greenhouse gases have seen slight declines over the past decade. These emission inventories are based on counts of equipment and operational activities (activity factors), multiplied by average emission factors, and therefore are subject to uncertainties in these factors. Although uncertainties associated with activity data and missing emission source types can be significant, multiple recent measurement studies indicate that the greatest uncertainties are associated with emission factors. In many source categories, small groups of devices or sites, referred to as super-emitters, contribute a large fraction of emissions. When super-emitters are accounted for, multiple measurement approaches, at multiple scales, produce similar results for estimated emissions. Challenges moving forward include identifying super-emitters and reducing their emission magnitudes. Work done to date suggests that both equipment malfunction and operational practices can be important. Finally, although most of this review focuses on emissions from energy supply infrastructures, the regional air quality implications of some coupled energy production and use scenarios are examined. These case studies suggest that both energy production and use should be considered in assessing air quality implications of changes in energy infrastructures, and that impacts are likely to vary among regions. The energy supply infrastructure in the United States has been changing dramatically over the past decade, leading to changes in emissions from oil and natural gas supply chain sources. In many source categories along these supply chains, small groups of devices or sites, referred to as super-emitters, contribute a large fraction of emissions. Effective emission reductions will require technologies for both identifying super-emitters and reducing their emission magnitudes.
Chen, Wenhui; Lei, Yalin
2017-02-01
Identifying the impact path on factors of CO 2 emissions is crucial for the government to take effective measures to reduce carbon emissions. The most existing research focuses on the total influence of factors on CO 2 emissions without differentiating between the direct and indirect influence. Moreover, scholars have addressed the relationships among energy consumption, economic growth, and CO 2 emissions rather than estimating all the causal relationships simultaneously. To fill this research gaps and explore overall driving factors' influence mechanism on CO 2 emissions, this paper utilizes a path analysis model with latent variables (PA-LV) to estimate the direct and indirect effect of factors on China's energy-related carbon emissions and to investigate the causal relationships among variables. Three key findings emanate from the analysis: (1) The change in the economic growth pattern inhibits the growth rate of CO 2 emissions by reducing the energy intensity; (2) adjustment of industrial structure contributes to energy conservation and CO 2 emission reduction by raising the proportion of the tertiary industry; and (3) the growth of CO 2 emissions impacts energy consumption and energy intensity negatively, which results in a negative impact indirectly on itself. To further control CO 2 emissions, the Chinese government should (1) adjust the industrial structure and actively develop its tertiary industry to improve energy efficiency and develop low-carbon economy, (2) optimize population shifts to avoid excessive population growth and reduce energy consumption, and (3) promote urbanization steadily to avoid high energy consumption and low energy efficiency.
Ishii, Tetsuro; Warabi, Eiji; Mann, Giovanni E
2018-05-01
Circadian clock genes regulate energy metabolism partly through neurotrophins in the body. The low affinity neurotrophin receptor p75 NTR is a clock component directly regulated by the transcriptional factor Clock:Bmal1 complex. Brain-derived neurotrophic factor (BDNF) is expressed in the brain and plays a key role in coordinating metabolic interactions between neurons and astrocytes. BDNF transduces signals through TrkB and p75 NTR receptors. This review highlights a novel molecular mechanism by which BDNF via circadian control of p75 NTR leads to daily resetting of glucose and glycogen metabolism in brain astrocytes to accommodate their functional interaction with neurons. Astrocytes store glycogen as an energy reservoir to provide active neurons with the glycolytic metabolite lactate. Astrocytes predominantly express the truncated receptor TrkB.T1 which lacks an intracellular receptor tyrosine kinase domain. TrkB.T1 retains the capacity to regulate cell morphology through regulation of Rho GTPases. In contrast, p75 NTR mediates generation of the bioactive lipid ceramide upon stimulation with BDNF and inhibits PKA activation. As ceramide directly activates PKCζ, we discuss the importance of the TrkB.T1-p75 NTR -ceramide-PKCζ signaling axis in the stimulation of glycogen and lipid synthesis and activation of RhoA. Ceramide-PKCζ-casein kinase 2 signaling activates Nrf2 to support oxidative phosphorylation via upregulation of antioxidant enzymes. In the absence of p75 NTR , TrkB.T1 functionally interacts with adenosine A 2A R and dopamine D1R receptors to enhance cAMP-PKA signaling and activate Rac1 and NF-κB c-Rel, favoring glycogen hydrolysis, gluconeogenesis and aerobic glycolysis. Thus, diurnal changes in p75 NTR levels in astrocytes resets energy metabolism via BDNF to accommodate their metabolic interaction with neurons. Copyright © 2018 Elsevier Inc. All rights reserved.
AE characteristic for monitoring of fatigue crack in steel bridge members
NASA Astrophysics Data System (ADS)
Yoon, Dong-Jin; Jung, Juong-Chae; Park, Philip; Lee, Seung-Seok
2000-06-01
Acoustic emission technique was employed for the monitoring of crack activity in both steel bridge members and laboratory specimen. Laboratory experiment was carried out to identify AE characteristics of fatigue cracks for compact tension specimen. The relationship between a stress intensity factor and AE signals activity as well as conventional AE parameter analysis was discussed. A field test was also conducted on a railway bridge, which contain several fatigue cracks. Crack activities were investigated while in service with strain measurement. From the results, in the laboratory tests, the features of three parameters such as the length of crack growth, the AE energy, and the cumulative AE events, showed the almost same trend in their increase as the number of fatigue cycle increased. From the comparisons of peak amplitude and AE energy with stress intensity factor, it was verified that the higher stress intensity factors generated AE signals with higher peak amplitude and a large number of AE counts. In the field test, real crack propagation signals were captured and the crack activity was verified in two cases.
DOE Office of Scientific and Technical Information (OSTI.GOV)
None
2001-08-01
This case study is the latest in a series on industrial firms who are implementing energy efficient technologies and system improvements into their manufacturing processes. The case studies document the activities, savings, and lessons learned on these projects.
Response functions for computing absorbed dose to skeletal tissues from photon irradiation—an update
NASA Astrophysics Data System (ADS)
Johnson, Perry B.; Bahadori, Amir A.; Eckerman, Keith F.; Lee, Choonsik; Bolch, Wesley E.
2011-04-01
A comprehensive set of photon fluence-to-dose response functions (DRFs) is presented for two radiosensitive skeletal tissues—active and total shallow marrow—within 15 and 32 bone sites, respectively, of the ICRP reference adult male. The functions were developed using fractional skeletal masses and associated electron-absorbed fractions as reported for the UF hybrid adult male phantom, which in turn is based upon micro-CT images of trabecular spongiosa taken from a 40 year male cadaver. The new DRFs expand upon both the original set of seven functions produced in 1985, and a 2007 update calculated under the assumption of secondary electron escape from spongiosa. In this study, it is assumed that photon irradiation of the skeleton will yield charged particle equilibrium across all spongiosa regions at energies exceeding 200 keV. Kerma coefficients for active marrow, inactive marrow, trabecular bone and spongiosa at higher energies are calculated using the DRF algorithm setting the electron-absorbed fraction for self-irradiation to unity. By comparing kerma coefficients and DRF functions, dose enhancement factors and mass energy-absorption coefficient (MEAC) ratios for active marrow to spongiosa were derived. These MEAC ratios compared well with those provided by the NIST Physical Reference Data Library (mean difference of 0.8%), and the dose enhancement factors for active marrow compared favorably with values calculated in the well-known study published by King and Spiers (1985 Br. J. Radiol. 58 345-56) (mean absolute difference of 1.9 percentage points). Additionally, dose enhancement factors for active marrow were shown to correlate well with the shallow marrow volume fraction (R2 = 0.91). Dose enhancement factors for the total shallow marrow were also calculated for 32 bone sites representing the first such derivation for this target tissue.
Johnson, Perry B; Bahadori, Amir A; Eckerman, Keith F; Lee, Choonsik; Bolch, Wesley E
2011-04-21
A comprehensive set of photon fluence-to-dose response functions (DRFs) is presented for two radiosensitive skeletal tissues-active and total shallow marrow-within 15 and 32 bone sites, respectively, of the ICRP reference adult male. The functions were developed using fractional skeletal masses and associated electron-absorbed fractions as reported for the UF hybrid adult male phantom, which in turn is based upon micro-CT images of trabecular spongiosa taken from a 40 year male cadaver. The new DRFs expand upon both the original set of seven functions produced in 1985, and a 2007 update calculated under the assumption of secondary electron escape from spongiosa. In this study, it is assumed that photon irradiation of the skeleton will yield charged particle equilibrium across all spongiosa regions at energies exceeding 200 keV. Kerma coefficients for active marrow, inactive marrow, trabecular bone and spongiosa at higher energies are calculated using the DRF algorithm setting the electron-absorbed fraction for self-irradiation to unity. By comparing kerma coefficients and DRF functions, dose enhancement factors and mass energy-absorption coefficient (MEAC) ratios for active marrow to spongiosa were derived. These MEAC ratios compared well with those provided by the NIST Physical Reference Data Library (mean difference of 0.8%), and the dose enhancement factors for active marrow compared favorably with values calculated in the well-known study published by King and Spiers (1985 Br. J. Radiol. 58 345-56) (mean absolute difference of 1.9 percentage points). Additionally, dose enhancement factors for active marrow were shown to correlate well with the shallow marrow volume fraction (R(2) = 0.91). Dose enhancement factors for the total shallow marrow were also calculated for 32 bone sites representing the first such derivation for this target tissue.
Factors associated with bat mortality at wind energy facilities in the United States
Thompson, Maureen; Beston, Julie A.; Etterson, Matthew A.; Diffendorfer, James E.; Loss, Scott R.
2017-01-01
Hundreds of thousands of bats are killed annually by colliding with wind turbines in the U.S., yet little is known about factors causing variation in mortality across wind energy facilities. We conducted a quantitative synthesis of bat collision mortality with wind turbines by reviewing 218 North American studies representing 100 wind energy facilities. This data set, the largest compiled for bats to date, provides further evidence that collision mortality is greatest for migratory tree-roosting species (Hoary Bat [Lasiurus cinereus], Eastern Red Bat [Lasiurus borealis], Silver-haired Bat [Lasionycteris noctivagans]) and from July to October. Based on 40 U.S. studies meeting inclusion criteria and analyzed under a common statistical framework to account for methodological variation, we found support for an inverse relationship between bat mortality and percent grassland cover surrounding wind energy facilities. At a national scale, grassland cover may best reflect openness of the landscape, a factor generally associated with reduced activity and abundance of tree-roosting species that may also reduce turbine collisions. Further representative sampling of wind energy facilities is required to validate this pattern. Ecologically informed placement of wind energy facilities involves multiple considerations, including not only factors associated with bat mortality, but also factors associated with bird collision mortality, indirect habitat-related impacts to all species, and overall ecosystem impacts.
Physical exercise, energy expenditure and tobacco consumption in adolescents from Murcia (Spain).
Rodríguez García, Pedro Luis; López Villalba, Francisco José; López Miñarro, Pedro Ángel; García Cantó, Eliseo
2014-02-01
Physical and sports activity is essential for a healthy lifestyle and is considered a prevention factor for several harmful habits on health. The purpose of this study was to establish the relationship between the level of physical activity, energy expenditure and tobacco consumption among adolescent students. Adolescent students aged 14 to 17 years old from the province of Murcia were included. Their level of physical activity was assessed using the International Physical Activity Questionnaire, and smoking was evaluated using the Youth Risk Behavior Surveillance. Out of 344 adolescents, 20.3% were overweight and 5.8%, obese. Of the total, 44.2% reported being active on a regular basis, while 55.8% were irregularly active or inactive. The level of physical exercise was higher among boys than girls. Tobacco was consumed by 20.3% of the sample, but no significant differences were observed based on sex. The highest energy expenditure from physical activity was positively associated with non consumption of tobacco. Among adolescents, a higher level of physical activity and a higher energy expenditure are positively associated with non consumption of tobacco.
More physically active and leaner adolescents have higher energy intake.
Cuenca-García, Magdalena; Ortega, Francisco B; Ruiz, Jonatan R; Labayen, Idoia; Moreno, Luis A; Patterson, Emma; Vicente-Rodríguez, Germán; González-Gross, Marcela; Marcos, Ascensión; Polito, Angela; Manios, Yannis; Beghin, Laurent; Huybrechts, Inge; Wästlund, Acki; Hurtig-Wennlöf, Anita; Hagströmer, Maria; Molnár, Dénes; Widhalm, Kurt; Kafatos, Anthony; De Henauw, Stefaan; Castillo, Manuel J; Gutin, Bernard; Sjöström, Michael
2014-01-01
To test whether youths who engage in vigorous physical activity are more likely to have lean bodies while ingesting relatively large amounts of energy. For this purpose, we studied the associations of both physical activity and adiposity with energy intake in adolescents. The study subjects were adolescents who participated in 1 of 2 cross-sectional studies, the Healthy Lifestyle in Europe by Nutrition in Adolescence (HELENA) study (n = 1450; mean age, 14.6 years) or the European Youth Heart Study (EYHS; n = 321; mean age, 15.6 years). Physical activity was measured by accelerometry, and energy intake was measured by 24-hour recall. In the HELENA study, body composition was assessed by 2 or more of the following methods: skinfold thickness, bioelectrical impedance analysis, plus dual-energy X-ray absorptiometry or air-displacement plethysmography in a subsample. In the EYHS, body composition was assessed by skinfold thickness. Fat mass was inversely associated with energy intake in both studies and using 4 different measurement methods (P ≤ .006). Overall, fat-free mass was positively associated with energy intake in both studies, yet the results were not consistent across measurement methods in the HELENA study. Vigorous physical activity in the HELENA study (P < .05) and moderate physical activity in the EYHS (P < .01) were positively associated with energy intake. Overall, results remained unchanged after adjustment for potential confounding factors, after mutual adjustment among the main exposures (physical activity and fat mass), and after the elimination of obese subjects, who might tend to underreport energy intake, from the analyses. Our data are consistent with the hypothesis that more physically active and leaner adolescents have higher energy intake than less active adolescents with larger amounts of fat mass. Copyright © 2014 Mosby, Inc. All rights reserved.
Space satellite power system. [conversion of solar energy by photovoltaic solar cell arrays
NASA Technical Reports Server (NTRS)
Glaser, P. E.
1974-01-01
The concept of a satellite solar power station was studied. It is shown that it offers the potential to meet a significant portion of future energy needs, is pollution free, and is sparing of irreplaceable earth resources. Solar energy is converted by photovoltaic solar cell arrays to dc energy which in turn is converted into microwave energy in a large active phased array. The microwave energy is beamed to earth with little attenuation and is converted back to dc energy on the earth. Economic factors are considered.
[Sedentary lifestyle: physical activity duration versus percentage of energy expenditure].
Cabrera de León, Antonio; Rodríguez-Pérez, María del C; Rodríguez-Benjumeda, Luis M; Anía-Lafuente, Basilio; Brito-Díaz, Buenaventura; Muros de Fuentes, Mercedes; Almeida-González, Delia; Batista-Medina, Marta; Aguirre-Jaime, Armando
2007-03-01
To compare different definitions of a sedentary lifestyle and to determine which is the most appropriate for demonstrating its relationship with the metabolic syndrome and other cardiovascular risk factors. A cross-sectional study of 5814 individuals was carried out. Comparisons were made between two definitions of a sedentary lifestyle: one based on active energy expenditure being less than 10% of total energy expenditure, and the other, on performing less than 25-30 minutes of physical activity per day. Reported levels of physical activity, anthropometric measurements, and biochemical markers of cardiovascular risk were recorded. The associations between a sedentary lifestyle and metabolic syndrome and other risk factors were adjusted for gender, age and tobacco use. The prevalence of a sedentary lifestyle was higher in women (70%) than in men (45-60%, according to the definition used). The definitions based on physical activity duration and on energy expenditure were equally useful: there were direct associations between a sedentary lifestyle and metabolic syndrome, body mass index, abdominal and pelvic circumferences, systolic blood pressure, heart rate, apolipoprotein B, and triglycerides, and inverse associations with high-density lipoprotein cholesterol and paraoxonase activity, which demonstrated the greatest percentage difference between sedentary and active individuals. An incidental finding was that both definitions of a sedentary lifestyle were more strongly associated with the metabolic syndrome as defined by International Diabetes Federation criteria than by Adult Treatment Panel III criteria. Given that it is relatively easy to determine whether a patient performs less than 25 minutes of physical activity per day, use of this definition of a sedentary lifestyle is recommended for clinical practice. The serum paraoxonase activity level could provide a useful marker for studying sedentary lifestyles.
Cai, Junmeng; Liu, Ronghou
2008-05-01
In the present paper, a new distributed activation energy model has been developed, considering the reaction order and the dependence of frequency factor on temperature. The proposed DAEM cannot be solved directly in a closed from, thus a method was used to obtain the numerical solution of the new DAEM equation. Two numerical examples to illustrate the proposed method were presented. The traditional DAEM and new DAEM have been used to simulate the pyrolytic process of some types of biomass. The new DAEM fitted the experimental data much better than the traditional DAEM as the dependence of the frequency factor on temperature was taken into account.
RDF (Refuse Derived Fuel) Utilization in a Navy Stoker Coal-Fired Boiler.
1984-10-01
the energy production in any coal-fired boiler conversion consideration. The selection of the actual RDF to be used in a converted boiler should be... industrial boilers by gathering information from the Navy Energy and Environmental Support Activity, engineering field divi- sions, and field...activities. Currently the Navy has 27 industrial size boilers firing coal as a primary fuel and 10 firing coal as a secondary fuel. The four principal factors
A NEW MODEL TO ESTIMATE DAILY ENERGY EXPENDITURE FOR WINTERING WATERFOWL
Activity budgets of wintering waterfowl have been widely used to assess habitat quality. However, when factors such as prey abundance or protection from exposure to cold or wind determine quality, measures of daily energy expenditure (DEE) may be more appropriate for this purpos...
USDA-ARS?s Scientific Manuscript database
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...
AN ENERGY SYSTEMS ANALYSIS OF CONSTRAINTS ON ECONOMIC DEVELOPMENT
There is a strong linear dependence of economic activity as measured by gross domestic product (GDP) on both the fossil fuel energy and the total emergy consumed by nations. Conceptual models of global and regional environmental systems were developed to examine the factors c...
O'dea, Jennifer A
2003-04-01
The goal was to have children and adolescents identify and rank the major perceived benefits of and barriers to healthful eating and physical activity and to suggest strategies for overcoming barriers. Semistructured, in-depth focus groups were undertaken using standardized questions and prompts. Students in grades 2 through 11(ages 7 through 17; N=213) from 34 randomly selected schools participated in 38 focus groups. Major benefits of healthful eating included improvements to cognitive and physical performance, fitness, endurance, psychological benefits, physical sensation (feeling good physically), and production of energy. Barriers included convenience, taste, and social factors. Benefits of physical activity included social benefits, enhancement of psychological status, physical sensation, and sports performance. Barriers included a preference for indoor activities, lack of energy and motivation, time constraints, and social factors. Suggested strategies for overcoming barriers included support from parents and school staff, better planning, time management, self-motivation, education, restructuring the physical environment, and greater variety of physical activities.
Carbon dioxide emissions from the electricity sector in major countries: a decomposition analysis.
Li, Xiangzheng; Liao, Hua; Du, Yun-Fei; Wang, Ce; Wang, Jin-Wei; Liu, Yanan
2018-03-01
The electric power sector is one of the primary sources of CO 2 emissions. Analyzing the influential factors that result in CO 2 emissions from the power sector would provide valuable information to reduce the world's CO 2 emissions. Herein, we applied the Divisia decomposition method to analyze the influential factors for CO 2 emissions from the power sector from 11 countries, which account for 67% of the world's emissions from 1990 to 2013. We decompose the influential factors for CO 2 emissions into seven areas: the emission coefficient, energy intensity, the share of electricity generation, the share of thermal power generation, electricity intensity, economic activity, and population. The decomposition analysis results show that economic activity, population, and the emission coefficient have positive roles in increasing CO 2 emissions, and their contribution rates are 119, 23.9, and 0.5%, respectively. Energy intensity, electricity intensity, the share of electricity generation, and the share of thermal power generation curb CO 2 emissions and their contribution rates are 17.2, 15.7, 7.7, and 2.8%, respectively. Through decomposition analysis for each country, economic activity and population are the major factors responsible for increasing CO 2 emissions from the power sector. However, the other factors from developed countries can offset the growth in CO 2 emissions due to economic activities.
Schnier, P D; Price, W D; Jockusch, R A; Williams, E R
1996-07-31
Blackbody infrared radiative dissociation (BIRD) spectra of singly and doubly protonated bradykinin and its analogues are measured in a Fourier-transform mass spectrometer. Rate constants for dissociation are measured as a function of temperature with reaction delays up to 600 s. From these data, Arrhenius activation parameters in the zero-pressure limit are obtained. The activation parameters and dissociation products for the singly protonated ions are highly sensitive to small changes in ion structure. The Arrhenius activation energy (E(a)) and pre-exponential (or frequency factor, A) of the singly protonated ions investigated here range from 0.6 to 1.4 eV and 10(5) to 10(12) s(-1), respectively. For bradykinin and its analogues differing by modification of the residues between the two arginine groups on either end of the molecule, the singly and doubly protonated ions have average activation energies of 1.2 and 0.8 eV, respectively, and average A values of 10(8) and 10(12) s(-1), respectively, i.e., the presence of a second charge reduces the activation energy by 0.4 eV and decreases the A value by a factor of 10(4). This demonstrates that the presence of a second charge can dramatically influence the dissociation dynamics of these ions. The doubly protonated methyl ester of bradykinin has an E(a) of 0.82 eV, comparable to the value of 0.84 eV for bradykinin itself. However, this value is 0.21 +/- 0.08 eV greater than that of singly protonated methyl ester of bradykinin, indicating that the Coulomb repulsion is not the most significant factor in the activation energy of this ion. Both singly and doubly protonated Lys-bradykinin ions have higher activation energies than the corresponding bradykinin ions indicating that the addition of a basic residue stabilizes these ions with respect to dissociation. Methylation of the carboxylic acid group of the C-terminus reduces the E(a) of bradykinin from 1.3 to 0.6 eV and the A factor from 1012 to 105 s(-1). This modification also dramatically changes the dissociation products. Similar results are observed for [Ala(6)]-bradykinin and its methyl ester. These results, in combination with others presented here, provide experimental evidence that the most stable form of singly protonated bradykinin is a salt-bridge structure.
Energy balance and obesity: what are the main drivers?
Romieu, Isabelle; Dossus, Laure; Barquera, Simón; Blottière, Hervé M; Franks, Paul W; Gunter, Marc; Hwalla, Nahla; Hursting, Stephen D; Leitzmann, Michael; Margetts, Barrie; Nishida, Chizuru; Potischman, Nancy; Seidell, Jacob; Stepien, Magdalena; Wang, Youfa; Westerterp, Klaas; Winichagoon, Pattanee; Wiseman, Martin; Willett, Walter C
2017-03-01
The aim of this paper is to review the evidence of the association between energy balance and obesity. In December 2015, the International Agency for Research on Cancer (IARC), Lyon, France convened a Working Group of international experts to review the evidence regarding energy balance and obesity, with a focus on Low and Middle Income Countries (LMIC). The global epidemic of obesity and the double burden, in LMICs, of malnutrition (coexistence of undernutrition and overnutrition) are both related to poor quality diet and unbalanced energy intake. Dietary patterns consistent with a traditional Mediterranean diet and other measures of diet quality can contribute to long-term weight control. Limiting consumption of sugar-sweetened beverages has a particularly important role in weight control. Genetic factors alone cannot explain the global epidemic of obesity. However, genetic, epigenetic factors and the microbiota could influence individual responses to diet and physical activity. Energy intake that exceeds energy expenditure is the main driver of weight gain. The quality of the diet may exert its effect on energy balance through complex hormonal and neurological pathways that influence satiety and possibly through other mechanisms. The food environment, marketing of unhealthy foods and urbanization, and reduction in sedentary behaviors and physical activity play important roles. Most of the evidence comes from High Income Countries and more research is needed in LMICs.
Compensation effect during the pyrolysis of tyres and bamboo.
Mui, Edward L K; Cheung, W H; Lee, Vinci K C; McKay, Gordon
2010-05-01
Pyrolysis parameters (e.g. pre-exponential factor A, and activation energy E) of two waste materials, namely, tyre rubber and bamboo scaffolding, based on the Arrhenius equation were obtained from weight loss data via thermogravimetry at different heating rates. The compensation effect, which suggests that the linear variation in the pre-exponential factor and the activation energy, was observed for these materials. This can be attributed to the variety of active sites over the reactant surface in the course of decomposition. The calculated data from several revised, first-order models were compared with similar models in the literature. It has been shown that both literature and our calculated data exhibit high linearity in terms of lnA and E, revealing that the latter agree well with other researchers' work. Copyright (c) 2010 Elsevier Ltd. All rights reserved.
Levine, James A.
2015-01-01
Running wheels are commonly employed to measure rodent physical activity in a variety of contexts, including studies of energy balance and obesity. There is no consensus on the nature of wheel-running activity or its underlying causes, however. Here, we will begin by systematically reviewing how running wheel availability affects physical activity and other aspects of energy balance in laboratory rodents. While wheel running and physical activity in the absence of a wheel commonly correlate in a general sense, in many specific aspects the two do not correspond. In fact, the presence of running wheels alters several aspects of energy balance, including body weight and composition, food intake, and energy expenditure of activity. We contend that wheel-running activity should be considered a behavior in and of itself, reflecting several underlying behavioral processes in addition to a rodent's general, spontaneous activity. These behavioral processes include defensive behavior, predatory aggression, and depression- and anxiety-like behaviors. As it relates to energy balance, wheel running engages several brain systems—including those related to the stress response, mood, and reward, and those responsive to growth factors—that influence energy balance indirectly. We contend that wheel-running behavior represents factors in addition to rodents' tendency to be physically active, engaging additional neural and physiological mechanisms which can then independently alter energy balance and behavior. Given the impact of wheel-running behavior on numerous overlapping systems that influence behavior and physiology, this review outlines the need for careful design and interpretation of studies that utilize running wheels as a means for exercise or as a measurement of general physical activity. PMID:22230703
Schnier, Paul D.; Price, William D.; Strittmatter, Eric F.; Williams, Evan R.
2005-01-01
The dissociation kinetics of protonated leucine enkephalin and its proton and alkali metal bound dimers were investigated by blackbody infrared radiative dissociation in a Fourier-transform mass spectrometer. From the temperature dependence of the unimolecular dissociation rate constants, Arrhenius activation parameters in the zero-pressure limit are obtained. Protonated leucine enkephalin dissociates to form b4 and (M−H2O)+ ions with an average activation energy (Ea) of 1.1 eV and an A factor of 1010.5 s−1. The value of the A factor indicates that these dissociation processes are rearrangements. The b4 ions subsequently dissociate to form a4 ions via a process with a relatively high activation energy (1.3 eV), but one that is entropically favored. For the cationized dimers, the thermal stability decreases with increasing cation size, consistent with a simple electrostatic interaction in these noncovalent ion–molecule complexes. The Ea and A factors are indistinguishable within experimental error with values of ~1.5 eV and 1017 s−1, respectively. Although not conclusive, results from master equation modeling indicate that all these BIRD processes, except for b4 → a4, are in the rapid energy exchange limit. In this limit, the internal energy of the precursor ion population is given by a Boltzmann distribution and information about the energetics and dynamics of the reaction are obtained directly from the measured Arrhenius parameters. PMID:16554908
Tyagi, Sandeep; Gupta, Paras; Saini, Arminder Singh; Kaushal, Chaitnya; Sharma, Saurabh
2011-01-01
Peroxisome proliferator-activated receptors (PPARs) are ligand-activated transcription factors of nuclear hormone receptor superfamily comprising of the following three subtypes: PPARα, PPARγ, and PPARβ/δ. Activation of PPAR-α reduces triglyceride level and is involved in regulation of energy homeostasis. Activation of PPAR-γ causes insulin sensitization and enhances glucose metabolism, whereas activation of PPAR-β/δ enhances fatty acids metabolism. Thus, PPAR family of nuclear receptors plays a major regulatory role in energy homeostasis and metabolic function. The present review critically analyzes the protective and detrimental effect of PPAR agonists in dyslipidemia, diabetes, adipocyte differentiation, inflammation, cancer, lung diseases, neurodegenerative disorders, fertility or reproduction, pain, and obesity. PMID:22247890
Zhang, Nan; Huang, Hong; Duan, Xiaoli; Zhao, Jinlong; Su, Boni
2018-06-21
Rapid urbanization is causing serious PM 2.5 (particulate matter ≤2.5 μm) pollution in China. However, the impacts of human activities (including industrial production, energy production, agriculture, and transportation) on PM 2.5 concentrations have not been thoroughly studied. In this study, we obtained a regression formula for PM 2.5 concentration based on more than 1 million PM 2.5 recorded values and data from meteorology, industrial production, energy production, agriculture, and transportation for 31 provinces of mainland China between January 2013 and May 2017. We used stepwise regression to process 49 factors that influence PM 2.5 concentration, and obtained the 10 primary influencing factors. Data of PM 2.5 concentration and 10 factors from June to December, 2017 was used to verify the robustness of the model. Excluding meteorological factors, production of natural gas, industrial boilers, and ore production have the highest association with PM 2.5 concentration, while nuclear power generation is the most positive factor in decreasing PM 2.5 concentration. Tianjin, Beijing, and Hebei provinces are the most vulnerable to high PM 2.5 concentrations caused by industrial production, energy production, agriculture, and transportation (IEAT).
Physical activity recommendations: an alternative approach using energy expenditure.
Mudd, Lanay M; Rafferty, Ann P; Reeves, Mathew J; Pivarnik, James M
2008-10-01
Most adults do not meet the American College of Sports Medicine and Centers for Disease Control and Prevention (ACSM/CDC) physical activity recommendations. Even fewer meet the more extreme Institute of Medicine (IOM) physical activity recommendations. Compliance with either recommendation has been conventionally assessed by combining frequencies and durations of self-reported activities. Leisure-time energy expenditure is a cumulative measure of activity that offers an alternative method of defining compliance. To calculate the leisure-time energy expenditure of adults complying with the ACSM/CDC or the IOM physical activity recommendations determined by conventional measures and to reexamine compliance with the IOM recommendation using energy expenditure criteria. National, cross-sectional data from the 2000 Behavioral Risk Factor Surveillance System determined the mode, frequency, and duration of up to two leisure-time activities performed by adults. Four mutually exclusive activity groups (Non-, Low-, ACSM/CDC-, and IOM-Active) were defined on the basis of frequencies and durations of reported activities. Leisure-time energy expenditure (kcal x kg(-1) x wk(-1)) was calculated per respondent. The energy expenditure threshold for meeting the IOM recommendation was calculated as 21 kcal x kg(-1) x wk(-1). Of the 162,669 respondents included in the analyses, 29.9% were Nonactive, whereas 42.3%, 23.3%, and 4.5% were Low-, ACSM/CDC-, and IOM-Active, respectively. Median leisure-time energy expenditure values were 9.0, 27.4, and 63.0 kcal x kg(-1) x wk(-1) for Low-, ACSM/CDC-, and IOM-Active groups, respectively. When using energy expenditure criteria, compliance with the IOM recommendation rose to 27.7% of respondents. Compliance with the IOM physical activity recommendation dramatically increased when assessed by energy expenditure compared with conventional criteria, thereby highlighting the potential bias of conventional methods. A significant proportion of adults meet the intent but not the letter of the IOM activity recommendation.
Energy use in Poland, 1970--1991: Sectoral analysis and international comparison
DOE Office of Scientific and Technical Information (OSTI.GOV)
Meyers, S.; Schipper, L.; Salay, J.
This report provides an analysis of how and why energy use has changed in Poland since the 1970s, with particular emphasis on changes since the country began its transition from a centrally planned to a market economy in 1989. The most important factors behind the large decline in Polish energy use in 1990 were a sharp fall in industrial output and a huge drop in residential coal use driven by higher prices. The structural shift away from heavy industry was slight. Key factors that worked to increase energy use were the rise in energy intensity in many heavy industries andmore » the shift toward more energy intensive modes of transport. The growth in private activities in 1991 was nearly sufficient to balance out continued decline in industrial energy use in that year. We compared energy use in Poland and the factors that shape it with similar elements in the West. We made a number of modifications to the Polish energy data to bring it closer to a Western energy accounting framework, and augmented these with a variety of estimates in order to construct a sufficiently detailed portrait of Polish energy use to allow comparison with Western data. Per capita energy use in Poland was not much below W. European levels despite Poland`s much lower GDP per capita. Poland has comparatively high energy intensities in manufacturing and residential space heating, and a large share of heavy industries in manufacturing output, all factors that contribute to higher energy use per capita. The structure of passenger and freight transportation and the energy intensity of automobiles contribute to lower energy use per capita in Poland than in Western Europe, but the patterns in Poland are moving closer to those that prevail in the West.« less
Energy Demands and Efficiency Strategies in Data Center Buildings
ERIC Educational Resources Information Center
Shehabi, Arman
2009-01-01
Information technology (IT) is becoming increasingly pervasive throughout society as more data is digitally processed, stored, and transferred. The infrastructure that supports IT activity is growing accordingly, and data center energy demands have increased by nearly a factor of four over the past decade. This dissertation investigates how…
Energy Expenditure During Extravehicular Activity Through Apollo
NASA Technical Reports Server (NTRS)
Paul, Heather L.
2011-01-01
Monitoring crew health during manned space missions has always been an important factor to ensure that the astronauts can complete the missions successfully and within safe physiological limits. The necessity of real-time metabolic rate monitoring during extravehicular activities (EVAs) came into question during the Gemini missions, when the energy expenditure required to complete EVA tasks exceeded the life support capabilities for cooling and humidity control and crewmembers (CMs) ended the EVAs fatigued and overworked. This paper discusses the importance of real-time monitoring of metabolic rate during EVA, and provides a historical look at energy expenditure during EVA through the Apollo program.
Parekh, Niyati; Lin, Yong; Marcella, Stephen; Kant, Ashima K; Lu-Yao, Grace
2008-09-01
Studies suggest inverse associations between obesity and prostate-specific antigen (PSA). However, there is little evidence whether factors related to obesity, including lifestyle (diet and physical activity) and physiologic factors (insulin resistance and metabolic syndrome), influence PSA. We used dietary, physical activity, and serum PSA, insulin, glucose, and lipid data for men >40 years from the National Health and Nutrition Examination Survey (2001-2004; N = 2,548). Energy, fat, and carbohydrate intakes were estimated from a 24-hour dietary recall. Men were considered as having metabolic syndrome based on the Adult Treatment Panel III criteria. Leisure-time physical activity and doctor-diagnosed hypertension were self-reported. Body mass index was calculated from measured weight and height. We computed the geometric mean PSA (ng/mL), adjusted for age, race, and body mass index, by tertile of energy, fat, and carbohydrate intake and level of physical activity, and among men with and without insulin resistance and metabolic syndrome in the whole population and by race. The geometric mean PSA (95% confidence interval) among men in the lowest tertile of energy was 1.05 (0.97-1.1) relative to 0.85 (0.8-0.9) in the highest tertile (P = 0.0002) in the whole population. The PSA concentrations were lower among overweight men with higher versus lower energy intake (P = 0.001). The PSA concentrations in men with insulin resistance was lower [0.87 (0.8-0.9)] relative to men without insulin resistance [0.98 (0.9-1.1)] at P = 0.04. All associations were in similar directions within racial subgroups. No associations were observed between the other lifestyle and physiologic factors. Additional studies are required to confirm these results and to investigate the potential mechanisms that may explain these relationships.
Ji, Liang; Nazarali, Adil J.; Paterson, Phyllis G.
2013-01-01
Protein–energy malnutrition (PEM) exacerbates functional impairment caused by brain ischemia. This is correlated with reactive gliosis, which suggests an increased inflammatory response. The objective of the current study was to investigate if PEM increases hippocampal activation of nuclear factor κB (NFκB), a transcription factor that amplifies the inflammatory response involved in ischemic brain injury. Mongolian gerbils (11–12 weeks old) were randomly assigned to control diet (12.5% protein) or protein-deficient diet (2%) for 4 weeks. The 2% protein group had a 15% decrease in voluntary food intake (P<.001; unpaired t test), resulting in PEM. Body weight after 4 weeks was 20% lower in the PEM group (P<.001). Gerbils were then exposed to sham surgery or global ischemia induced by 5-min bilateral common carotid artery occlusion. PEM independently increased hippocampal NFκB activation detected by electrophoretic mobility shift assay at 6 h after surgery (P=.014; 2-factor ANOVA). Ischemia did not significantly affect NFκB activation nor was there interaction between diet and ischemia. Serum glucose and cortisol concentrations at 6 h postischemia were unaltered by diet or ischemia. A second experiment using gerbils of the same age and feeding paradigm demonstrated that PEM also increases hippocampal NFκB activation in the absence of surgery. These findings suggest that PEM, which exists in 16% of elderly patients at admission for stroke, may worsen outcome by increasing activation of NFκB. Since PEM increased NFκB activation independent of ischemia or surgery, the data also have implications for the inflammatory response of the many individuals affected globally by PEM. PMID:18430555
Coupling DAEM and CFD for simulating biomass fast pyrolysis in fluidized beds
Xiong, Qingang; Zhang, Jingchao; Wiggins, Gavin; ...
2015-12-03
We report results from computational simulations of an experimental, lab-scale bubbling bed biomass pyrolysis reactor that include a distributed activation energy model (DAEM) for the kinetics. In this study, we utilized multiphase computational fluid dynamics (CFD) to account for the turbulent hydrodynamics, and this was combined with the DAEM kinetics in a multi-component, multi-step reaction network. Our results indicate that it is possible to numerically integrate the coupled CFD–DAEM system without significantly increasing computational overhead. It is also clear, however, that reactor operating conditions, reaction kinetics, and multiphase flow dynamics all have major impacts on the pyrolysis products exiting themore » reactor. We find that, with the same pre-exponential factors and mean activation energies, inclusion of distributed activation energies in the kinetics can shift the predicted average value of the exit vapor-phase tar flux and its statistical distribution, compared to single-valued activation-energy kinetics. Perhaps the most interesting observed trend is that increasing the diversity of the DAEM activation energies appears to increase the mean tar yield, all else being equal. As a result, these findings imply that accurate resolution of the reaction activation energy distributions will be important for optimizing biomass pyrolysis processes.« less
Weight Management for Athletes and Active Individuals: A Brief Review.
Manore, Melinda M
2015-11-01
Weight management for athletes and active individuals is unique because of their high daily energy expenditure; thus, the emphasis is usually placed on changing the diet side of the energy balance equation. When dieting for weight loss, active individuals also want to preserve lean tissue, which means that energy restriction cannot be too severe or lean tissue is lost. First, this brief review addresses the issues of weight management in athletes and active individuals and factors to consider when determining a weight-loss goal. Second, the concept of dynamic energy balance is reviewed, including two mathematical models developed to improve weight-loss predictions based on changes in diet and exercise. These models are now available on the Internet. Finally, dietary strategies for weight loss/maintenance that can be successfully used with active individuals are given. Emphasis is placed on teaching the benefits of consuming a low-ED diet (e.g., high-fiber, high-water, low-fat foods), which allows for the consumption of a greater volume of food to increase satiety while reducing energy intake. Health professionals and sport dietitians need to understand dynamic energy balance and be prepared with effective and evidence-based dietary approaches to help athletes and active individuals achieve their body-weight goals.
Physical Activity Energy Expenditure and Sarcopenia in Black South African Urban Women.
Kruger, Herculina S; Havemann-Nel, Lize; Ravyse, Chrisna; Moss, Sarah J; Tieland, Michael
2016-03-01
Black women are believed to be genetically less predisposed to age-related sarcopenia. The objective of this study was to investigate lifestyle factors associated with sarcopenia in black South African (SA) urban women. In a cross-sectional study, 247 women (mean age 57 y) were randomly selected. Anthropometric and sociodemographic variables, dietary intakes, and physical activity were measured. Activity was also measured by combined accelerometery/heart rate monitoring (ActiHeart), and HIV status was tested. Dual energy x-ray absorptiometry was used to measure appendicular skeletal mass (ASM). Sarcopenia was defined according to a recently derived SA cutpoint of ASM index (ASM/height squared) < 4.94 kg/m(2). In total, 8.9% of the women were sarcopenic, decreasing to 8.1% after exclusion of participants who were HIV positive. In multiple regressions with ASM index, grip strength, and gait speed, respectively, as dependent variables, only activity energy expenditure (β = .27) was significantly associated with ASM index. Age (β = -.50) and activity energy expenditure (β = .17) were significantly associated with gait speed. Age (β = -.11) and lean mass (β = .21) were significantly associated with handgrip strength. Sarcopenia was prevalent among these SA women and was associated with low physical activity energy expenditure.
Tachinardi, Patricia; Valentinuzzi, Verónica S; Oda, Gisele A; Buck, C Loren
The tuco-tuco (Ctenomys aff. knighti) is among the rodent species known to be nocturnal under standard laboratory conditions and diurnal under natural conditions. The circadian thermoenergetics (CTE) hypothesis postulates that switches in activity timing are a response to energetic challenges; daytime activity reduces thermoregulatory costs by consolidating activity to the warmest part of the day. Studying wild animals under both captive and natural conditions can increase understanding of how temporal activity patterns are shaped by the environment and could serve as a test of the CTE hypothesis. We estimated the effects of activity timing on energy expenditure for the tuco-tuco by combining laboratory measurements of metabolic rate with environmental temperature records in both winter and summer. We showed that, in winter, there would be considerable energy savings if activity is allocated at least partially during daylight, lending support to the CTE hypothesis. In summer, the impact of activity timing on energy expenditure is small, suggesting that during this season other factors, such as predation risk, water balance, and social interaction, may have more important roles than energetics in the determination of activity time.
Photonic crystal lasers using wavelength-scale embedded active region
NASA Astrophysics Data System (ADS)
Matsuo, Shinji; Sato, Tomonari; Takeda, Koji; Shinya, Akihiko; Nozaki, Kengo; Kuramochi, Eiichi; Taniyama, Hideaki; Notomi, Masaya; Fujii, Takuro; Hasebe, Koichi; Kakitsuka, Takaaki
2014-01-01
Lasers with ultra-low operating energy are desired for use in chip-to-chip and on-chip optical interconnects. If we are to reduce the operating energy, we must reduce the active volume. Therefore, a photonic crystal (PhC) laser with a wavelength-scale cavity has attracted a lot of attention because a PhC provides a large Q-factor with a small volume. To improve this device's performance, we employ an embedded active region structure in which the wavelength-scale active region is buried with an InP PhC slab. This structure enables us to achieve effective confinement of both carriers and photons, and to improve the thermal resistance of the device. Thus, we have obtained a large external differential quantum efficiency of 55% and an output power of -10 dBm by optical pumping. For electrical pumping, we use a lateral p-i-n structure that employs Zn diffusion and Si ion implantation for p-type and n-type doping, respectively. We have achieved room-temperature continuous-wave operation with a threshold current of 7.8 µA and a maximum 3 dB bandwidth of 16.2 GHz. The results of an experimental bit error rate measurement with a 10 Gbit s-1 NRZ signal reveal the minimum operating energy for transferring a single bit of 5.5 fJ. These results show the potential of this laser to be used for very short reach interconnects. We also describe the optimal design of cavity quality (Q) factor in terms of achieving a large output power with a low operating energy using a calculation based on rate equations. When we assume an internal absorption loss of 20 cm-1, the optimized coupling Q-factor is 2000.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Collier, Virginia E.; Ellebracht, Nathan C.; Lindy, George I.
The kinetic and mechanistic understanding of cooperatively catalyzed aldol and nitroaldol condensations is probed using a series of mesoporous silicas functionalized with aminosilanes to provide bifunctional acid–base character. Mechanistically, a Hammett analysis is performed to determine the effects of electron-donating and electron-withdrawing groups of para-substituted benzaldehyde derivatives on the catalytic activity of each condensation reaction. This information is also used to discuss the validity of previously proposed catalytic mechanisms and to propose a revised mechanism with plausible reaction intermediates. For both reactions, electron-withdrawing groups increase the observed rates of reaction, though resonance effects play an important, yet subtle, role inmore » the nitroaldol condensation, in which a p-methoxy electron-donating group is also able to stabilize the proposed carbocation intermediate. Additionally, activation energies and pre-exponential factors are calculated via the Arrhenius analysis of two catalysts with similar amine loadings: one catalyst had silanols available for cooperative interactions (acid–base catalysis), while the other was treated with a silanol-capping reagent to prevent such cooperativity (base-only catalysis). The values obtained for activation energies and pre-exponential factors in each reaction are discussed in the context of the proposed mechanisms and the importance of cooperative interactions in each reaction. The catalytic activity decreases for all reactions when the silanols are capped with trimethylsilyl groups, and higher temperatures are required to make accurate rate measurements, emphasizing the vital role the weakly acidic silanols play in the catalytic cycles. The results indicate that loss of acid sites is more detrimental to the catalytic activity of the aldol condensation than the nitroaldol condensation, as evidenced by the significant decrease in the pre-exponential factor for the aldol condensation when silanols are unavailable for cooperative interactions. Cooperative catalysis is evidenced by significant changes in the pre-exponential factor, rather than the activation energy for the aldol condensation.« less
Collier, Virginia E.; Ellebracht, Nathan C.; Lindy, George I.; ...
2015-12-09
The kinetic and mechanistic understanding of cooperatively catalyzed aldol and nitroaldol condensations is probed using a series of mesoporous silicas functionalized with aminosilanes to provide bifunctional acid–base character. Mechanistically, a Hammett analysis is performed to determine the effects of electron-donating and electron-withdrawing groups of para-substituted benzaldehyde derivatives on the catalytic activity of each condensation reaction. This information is also used to discuss the validity of previously proposed catalytic mechanisms and to propose a revised mechanism with plausible reaction intermediates. For both reactions, electron-withdrawing groups increase the observed rates of reaction, though resonance effects play an important, yet subtle, role inmore » the nitroaldol condensation, in which a p-methoxy electron-donating group is also able to stabilize the proposed carbocation intermediate. Additionally, activation energies and pre-exponential factors are calculated via the Arrhenius analysis of two catalysts with similar amine loadings: one catalyst had silanols available for cooperative interactions (acid–base catalysis), while the other was treated with a silanol-capping reagent to prevent such cooperativity (base-only catalysis). The values obtained for activation energies and pre-exponential factors in each reaction are discussed in the context of the proposed mechanisms and the importance of cooperative interactions in each reaction. The catalytic activity decreases for all reactions when the silanols are capped with trimethylsilyl groups, and higher temperatures are required to make accurate rate measurements, emphasizing the vital role the weakly acidic silanols play in the catalytic cycles. The results indicate that loss of acid sites is more detrimental to the catalytic activity of the aldol condensation than the nitroaldol condensation, as evidenced by the significant decrease in the pre-exponential factor for the aldol condensation when silanols are unavailable for cooperative interactions. Cooperative catalysis is evidenced by significant changes in the pre-exponential factor, rather than the activation energy for the aldol condensation.« less
Energy metabolism, body composition, and urea generation rate in hemodialysis patients.
Sridharan, Sivakumar; Vilar, Enric; Berdeprado, Jocelyn; Farrington, Ken
2013-10-01
Hemodialysis (HD) adequacy is currently assessed using normalized urea clearance (Kt/V), although scaling based on Watson volume (V) may disadvantage women and men with low body weight. Alternative scaling factors such as resting energy expenditure and high metabolic rate organ mass have been suggested. The relationship between such factors and uremic toxin generation has not been established. We aimed to study the relationship between body size, energy metabolism, and urea generation rate. A cross-sectional cohort of 166 HD patients was studied. Anthropometric measurements were carried on all. Resting energy expenditure was measured by indirect calorimetry, fat-free mass by bio-impedance and total energy expenditure by combining resting energy expenditure with a questionnaire-derived physical activity data. High metabolic rate organ mass was calculated using a published equation and urea generation rate using formal urea kinetic modeling. Metabolic factors including resting energy expenditure, total energy expenditure and fat-free mass correlated better with urea generation rate than did Watson volume. Total energy expenditure and fat-free mass (but not Watson Volume) were independent predictors of urea generation rate, the model explaining 42% of its variation. Small women (
Anaerobic fitness tests: what are we measuring?
Van Praagh, Emmanuel
2007-01-01
Anaerobic fitness, during growth and development, has not received the same attention from researchers as aerobic fitness. This is surprising given the level of anaerobic energy used daily during childhood and adolescence. During physical activity and sport, the child is spontaneously more attracted to short-burst movements than to long-term activities. It is, however, well known that in anaerobic activities such as sprint cycling, sprint running or sprint swimming, the child's performance is distinctly poorer than that of the adult. This partly reflects the child's lesser ability to generate mechanical energy from chemical energy sources during short-term high-intensity work or exercise. Direct measurements of the rate or capacity of anaerobic pathways for energy turnover presents several ethical and methodological difficulties. Therefore, rather than measure energy supply, pediatric exercise scientists have concentrated on measuring short-term power output by means of standardized protocol tests such as short-term cycling power tests, running tests or vertical jump tests. There is, however, no perfect test and, therefore, it is important to acknowledge the benefits and limitations of each testing method. Mass-related short-term power output was shown to increase dramatically during growth and development, whereas the corresponding increase in peak blood lactate was considerably lower. This suggests that the observed difference between children and adolescents during short-term power output testing may be related to neuromuscular factors, hormonal factors and improved motor coordination.
Rafii, Forough; Seyedfatemi, Naima; Rezaei, Mahboubeh
2013-01-01
We aimed to explore and describe the factors involved in Iranian women heads of household’s health promotion activities. Grounded theory was used as the method. Sixteen women heads of household were recruited. Data were generated by semi structured interviews. Our findings indicated that remainder of resources (money, time and energy) alongside perceived severity of health risk were two main factors whereas women’s personal and socio-economic characteristics were two contextual factors involved in these women's health promotion activities. To help these women improve their health status, we recommended that the government, non-governmental organizations and health care professionals provide them with required resources and increase their knowledge by holding training sessions. PMID:24039645
Rankin, D; Ellis, S M; Macintyre, U E; Hanekom, S M; Wright, H H
2011-08-01
The objective of this study is to determine the relative validity of reported energy intake (EI) derived from multiple 24-h recalls against estimated energy expenditure (EE(est)). Basal metabolic rate (BMR) equations and physical activity factors were incorporated to calculate EE(est). This analysis was nested in the multidisciplinary PhysicaL Activity in the Young study with a prospective study design. Peri-urban black South African adolescents were investigated in a subsample of 131 learners (87 girls and 44 boys) from the parent study sample of 369 (211 girls and 158 boys) who had all measurements taken. Pearson correlation coefficients and Bland-Altman plots were calculated to identify the most accurate published equations to estimate BMR (P<0.05 statistically significant). EE(est) was estimated using BMR equations and estimated physical activity factors derived from Previous Day Physical Activity Recall questionnaires. After calculation of EE(est), the relative validity of reported energy intake (EI(rep)) derived from multiple 24-h recalls was tested for three data subsets using Pearson correlation coefficients. Goldberg's formula identified cut points (CPs) for under and over reporting of EI. Pearson correlation coefficients between calculated BMRs ranged from 0.97 to 0.99. Bland-Altman analyses showed acceptable agreement (two equations for each gender). One equation for each gender was used to calculate EE(est). Pearson correlation coefficients between EI(rep) and EE(est) for three data sets were weak, indicating poor agreement. CPs for physical activity groups showed under reporting in 87% boys and 95% girls. The 24-h recalls measured at five measurements over 2 years offered poor validity between EI(rep) and EE(est).
Tooze, Janet A; Troiano, Richard P; Carroll, Raymond J; Moshfegh, Alanna J; Freedman, Laurence S
2013-06-01
Systematic investigations into the structure of measurement error of physical activity questionnaires are lacking. We propose a measurement error model for a physical activity questionnaire that uses physical activity level (the ratio of total energy expenditure to basal energy expenditure) to relate questionnaire-based reports of physical activity level to true physical activity levels. The 1999-2006 National Health and Nutrition Examination Survey physical activity questionnaire was administered to 433 participants aged 40-69 years in the Observing Protein and Energy Nutrition (OPEN) Study (Maryland, 1999-2000). Valid estimates of participants' total energy expenditure were also available from doubly labeled water, and basal energy expenditure was estimated from an equation; the ratio of those measures estimated true physical activity level ("truth"). We present a measurement error model that accommodates the mixture of errors that arise from assuming a classical measurement error model for doubly labeled water and a Berkson error model for the equation used to estimate basal energy expenditure. The method was then applied to the OPEN Study. Correlations between the questionnaire-based physical activity level and truth were modest (r = 0.32-0.41); attenuation factors (0.43-0.73) indicate that the use of questionnaire-based physical activity level would lead to attenuated estimates of effect size. Results suggest that sample sizes for estimating relationships between physical activity level and disease should be inflated, and that regression calibration can be used to provide measurement error-adjusted estimates of relationships between physical activity and disease.
Zhang, Xiongliang; Yan, Xiaoyu; Wang, Chunyang; Tang, Tingting; Chai, Yimin
2014-01-01
Extracorporeal shock wave therapy (ESWT) has been demonstrated to have the angiogenic effect on ischemic tissue. We hypothesize that ESWT exerts the proangiogenesis effect with an energy density-dependent mode on the target cells. Endothelial progenitor cells (EPCs) of rats were obtained by cultivation of bone marrow-derived mononuclear cells. EPCs were divided into five groups of different energy densities, and each group was furthermore subdivided into four groups of different shock numbers. Thus, there were 20 subgroups in total. The expressions of angiogenic factors, apoptotic factors, inflammation mediators, and chemotactic factors were examined, and the proliferation activity was measured after ESWT. When EPCs were treated with low-energy (0.04-0.13 mJ/mm(2)) shock wave, the expressions of endothelial nitric oxide synthase, angiopoietin (Ang) 1, Ang-2, and B-cell lymphoma 2 increased and those of interleukin 6, fibroblast growth factor 2, C-X-C chemokine receptor type 4, vascular endothelial growth factor a, Bcl-2-associated X protein, and caspase 3 decreased. stromal cell-derived factor 1 changed without statistical significance. When cells were treated with high-energy (0.16 mJ/mm(2)) shock wave, most of the expressions of cytokines declined except the apoptotic factors and fibroblast growth factor 2, and cells lead to apoptosis. The proliferation activity and the ratio of Ang-1/Ang-2 reached their peak values, when cells were treated with ESWT with the intensity ranging from 0.10-0.13 mJ/mm(2) and shock number ranging from 200-300 impulses. Meanwhile, a minimal value of the ratio of Bax/Bcl-2 was observed. There is a dose-effect relationship in ESWT. The shock intensity ranging from 0.10-0.13 mJ/mm(2) and shock number ranging from 200-300 impulses were the optimal parameters for ESWT to treat cells in vitro. Crown Copyright © 2014. Published by Elsevier Inc. All rights reserved.
Energy Blocks — A Physical Model for Teaching Energy Concepts
NASA Astrophysics Data System (ADS)
Hertting, Scott
2016-01-01
Most physics educators would agree that energy is a very useful, albeit abstract topic. It is therefore important to use various methods to help the student internalize the concept of energy itself and its related ideas. These methods include using representations such as energy bar graphs, energy pie charts, or energy tracking diagrams. Activities and analogies like Energy Theater and Richard Feynman's blocks, as well as the popular money (or wealth) analogy, can also be very effective. The goal of this paper is to describe a physical model of Feynman's blocks that can be employed by instructors to help students learn the following energy-related concepts: 1. The factors affecting each individual mechanical energy storage mode (this refers to what has been traditionally called a form of energy, and while the Modeling Method of instruction is not the focus of this paper, much of the energy related language used is specific to the Modeling Method). For example, how mass or height affects gravitational energy; 2. Energy conservation; and 3. The graphical relationships between the energy storage mode and a factor affecting it. For example, the graphical relationship between elastic energy and the change in length of a spring.
Harahap, Heryudarini; Sandjaja, Sandjaja; Soekatri, Moesijanti; Khouw, Ilse; Deurenberg, Paul
2018-01-01
Indonesia is currently facing double burden malnutrition in children. As overweight and obesity are due to a disturbed energy balance, this study aimed to assess the association of total energy intake and physical activity with the prevalence of overweight among Indonesian children. The data used for this analysis were from 1143 children, 6-12 years old, that participated in the South East Asian Nutrition Survey (SEANUTS). Physical activity (PA) was measured using pedometers for 2 consecutive days and was categorized low, moderate and high. Child nutritional status was categorized based on body mass index for age z-scores (BAZ) into normal weight (-2 SD ≤BAZ≤1 SD) or overweight (BAZ >1 SD). Energy intake was calculated from a one day 24 hour recall and compared to the Indonesian recommended dietary allowance (RDA) for energy. Children with low PA had higher risk (ODDs 3.4, 95% CI: 2.0, 6.0) of being overweight compared to children who had high PA. Children with moderate PA and energy take >100% RDA had higher risk (ODDs 4.2, 95% CI 1.9, 9.3) of being overweight than children with high PA and energy intakes ≤100% RDA. Low physical activity independently or moderate physical activity and high energy intake are risk factors for Indonesian children to get overweight. Program intervention such as increasing physical activity at school and home is needed to reduce overweight among children.
Comparison of measured versus predicted energy requirements in critically ill cancer patients.
Pirat, Arash; Tucker, Anne M; Taylor, Kim A; Jinnah, Rashida; Finch, Clarence G; Canada, Todd D; Nates, Joseph L
2009-04-01
Accurate determination of caloric requirements is essential to avoid feeding-associated complications in critically ill patients. In critically ill cancer patients we compared the measured and estimated resting energy expenditures. All patients admitted to the oncology intensive care unit between March 2004 and July 2005 were considered for inclusion. For those patients enrolled (n = 34) we measured resting energy expenditure via indirect calorimetry, and estimated resting energy expenditure in 2 ways: clinically estimated resting energy expenditure; and the Harris-Benedict basal energy expenditure equation. Clinically estimated resting energy expenditure was associated with underfeeding, appropriate feeding, and overfeeding in approximately 15%, 15%, and 71% of the patients, respectively. The Harris-Benedict basal energy expenditure was associated with underfeeding, appropriate feeding, and overfeeding in approximately 29%, 41%, and 29% of the patients, respectively. The mean measured resting energy expenditure (1,623 +/- 384 kcal/d) was similar to the mean Harris-Benedict basal energy expenditure without the addition of stress or activity factors (1,613 +/- 382 kcal/d, P = .87), and both were significantly lower than the mean clinically estimated resting energy expenditure (1,862 +/- 330 kcal/d, P < or = .003 for both). There was a significant correlation only between mean measured resting energy expenditure and mean Harris-Benedict basal energy expenditure (P < .001), but the correlation coefficient between those values was low (r = 0.587). Underfeeding and overfeeding were common in our critically ill cancer patients when resting energy expenditure was estimated rather than measured. Indirect calorimetry is the method of choice for determining caloric need in critically ill cancer patients, but if indirect calorimetry is not available or feasible, the Harris-Benedict equation without added stress and activity factors is more accurate than the clinically estimated resting energy expenditure.
Langlois, Johanne; Omorou, Abdou Y; Vuillemin, Anne; Briançon, Serge; Lecomte, Edith
2017-02-08
Social differences among adolescents in physical activity and sedentary behaviour have been identified but are not well explained. The current study aimed to identify socioeconomic, family and school-related associated factors with physical activity and sedentary behaviour among high-school adolescents. This was a cross-sectional analysis of T0 physical activity and sedentary behaviour of 2523 students 14 - 18 years old recruited for the PRALIMAP trial from 24 French state-run high schools. Data were collected by self-administered questionnaire at the start of grade 10. Adolescents completed the International Physical Activity Questionnaire for physical activity and sedentary behaviour and an ad hoc questionnaire for active commuting and sport participation. Statistical analyses involved linear and logistic regressions. Socioeconomic, family or school variables were associated with levels of physical activity and sedentary behaviour for both boys and girls, but no factor, except perceived parental physical activity level, was associated with total energy expenditure (total physical activity) for either gender. Adolescents with privileged and less privileged socioeconomic status reported the same total amount of energy expenditure. Total physical activity score alone is not sufficient to assess the physical activity of adolescents. These findings may have implications for better understanding of social inequalities in this context and recommendations to prevent overweight. This trial is registered at ClinicalTrials.gov ( NCT00814554 ). The date of registration: 23 December 2008. Registration was not required at the time of the start of PRALIMAP for public health and prevention programmes and trials.
Rong, Xing; Du, Yong; Frey, Eric C
2012-06-21
Quantitative Yttrium-90 ((90)Y) bremsstrahlung single photon emission computed tomography (SPECT) imaging has shown great potential to provide reliable estimates of (90)Y activity distribution for targeted radionuclide therapy dosimetry applications. One factor that potentially affects the reliability of the activity estimates is the choice of the acquisition energy window. In contrast to imaging conventional gamma photon emitters where the acquisition energy windows are usually placed around photopeaks, there has been great variation in the choice of the acquisition energy window for (90)Y imaging due to the continuous and broad energy distribution of the bremsstrahlung photons. In quantitative imaging of conventional gamma photon emitters, previous methods for optimizing the acquisition energy window assumed unbiased estimators and used the variance in the estimates as a figure of merit (FOM). However, for situations, such as (90)Y imaging, where there are errors in the modeling of the image formation process used in the reconstruction there will be bias in the activity estimates. In (90)Y bremsstrahlung imaging this will be especially important due to the high levels of scatter, multiple scatter, and collimator septal penetration and scatter. Thus variance will not be a complete measure of reliability of the estimates and thus is not a complete FOM. To address this, we first aimed to develop a new method to optimize the energy window that accounts for both the bias due to model-mismatch and the variance of the activity estimates. We applied this method to optimize the acquisition energy window for quantitative (90)Y bremsstrahlung SPECT imaging in microsphere brachytherapy. Since absorbed dose is defined as the absorbed energy from the radiation per unit mass of tissues in this new method we proposed a mass-weighted root mean squared error of the volume of interest (VOI) activity estimates as the FOM. To calculate this FOM, two analytical expressions were derived for calculating the bias due to model-mismatch and the variance of the VOI activity estimates, respectively. To obtain the optimal acquisition energy window for general situations of interest in clinical (90)Y microsphere imaging, we generated phantoms with multiple tumors of various sizes and various tumor-to-normal activity concentration ratios using a digital phantom that realistically simulates human anatomy, simulated (90)Y microsphere imaging with a clinical SPECT system and typical imaging parameters using a previously validated Monte Carlo simulation code, and used a previously proposed method for modeling the image degrading effects in quantitative SPECT reconstruction. The obtained optimal acquisition energy window was 100-160 keV. The values of the proposed FOM were much larger than the FOM taking into account only the variance of the activity estimates, thus demonstrating in our experiment that the bias of the activity estimates due to model-mismatch was a more important factor than the variance in terms of limiting the reliability of activity estimates.
Experimental Evaluation of a Carbon Slurry Droplet Combustion Model
1981-12-14
the increased mass and energy transport due to the flow percolating through the open porous structure of the carbon agglomerate. Two separate models...catalysts. Transport-rate enhancement factors were also employed in the carbon-agglomerate reaction analysis to account for the increased mass and energy ...D Effective binary diffusivity Ei Activation energy h Heat transfer coefficient H2 Diatomic hydrogen H20 Water i Enthalpy if Enthalpy of formation
NASA Astrophysics Data System (ADS)
Xi, Wen; Song, Xiaoqing; Hu, Shi; Chen, Zheng
2017-11-01
In this work, the phase field crystal (PFC) method is used to study the localized solid-state amorphization (SSA) and its dynamic transformation process in polycrystalline materials under the uniaxial tensile deformation with different factors. The impacts of these factors, including strain rates, temperatures and grain sizes, are analyzed. Kinetically, the ultra-high strain rate causes the lattice to be seriously distorted and the grain to gradually collapse, so the dislocation density rises remarkably. Therefore, localized SSA occurs. Thermodynamically, as high temperature increases the activation energy, the atoms are active and prefer to leave the original position, which induce atom rearrangement. Furthermore, small grain size increases the percentage of grain boundary and the interface free energy of the system. As a result, Helmholtz free energy increases. The dislocations and Helmholtz free energy act as the seed and driving force for the process of the localized SSA. Also, the critical diffusion-time step and the percentage of amorphous region areas are calculated. Through this work, the PFC method is proved to be an effective means to study localized SSA under uniaxial tensile deformation.
Xi, Wen; Song, Xiaoqing; Hu, Shi; Chen, Zheng
2017-11-29
In this work, the phase field crystal (PFC) method is used to study the localized solid-state amorphization (SSA) and its dynamic transformation process in polycrystalline materials under the uniaxial tensile deformation with different factors. The impacts of these factors, including strain rates, temperatures and grain sizes, are analyzed. Kinetically, the ultra-high strain rate causes the lattice to be seriously distorted and the grain to gradually collapse, so the dislocation density rises remarkably. Therefore, localized SSA occurs. Thermodynamically, as high temperature increases the activation energy, the atoms are active and prefer to leave the original position, which induce atom rearrangement. Furthermore, small grain size increases the percentage of grain boundary and the interface free energy of the system. As a result, Helmholtz free energy increases. The dislocations and Helmholtz free energy act as the seed and driving force for the process of the localized SSA. Also, the critical diffusion-time step and the percentage of amorphous region areas are calculated. Through this work, the PFC method is proved to be an effective means to study localized SSA under uniaxial tensile deformation.
Dulloo, A G; Jacquet, J; Miles-Chan, J L; Schutz, Y
2017-03-01
While putative feedback signals arising from adipose tissue are commonly assumed to provide the molecular links between the body's long-term energy requirements and energy intake, the available evidence suggests that the lean body or fat-free mass (FFM) also plays a role in the drive to eat. A distinction must, however, be made between a 'passive' role of FFM in driving energy intake, which is likely to be mediated by 'energy-sensing' mechanisms that translate FFM-induced energy requirements to energy intake, and a more 'active' role of FFM in the drive to eat through feedback signaling between FFM deficit and energy intake. Consequently, a loss of FFM that results from dieting or sedentarity should be viewed as a risk factor for weight regain and increased fatness not only because of the impact of the FFM deficit in lowering the maintenance energy requirement but also because of the body's attempt to restore FFM by overeating-a phenomenon referred to as 'collateral fattening'. A better understanding of these passive and active roles of FFM in the control of energy intake will necessitate the elucidation of peripheral signals and energy-sensing mechanisms that drive hunger and appetite, with implications for both obesity prevention and its management.
Water diffusion in silicate glasses: the effect of glass structure
NASA Astrophysics Data System (ADS)
Kuroda, M.; Tachibana, S.
2016-12-01
Water diffusion in silicate melts (glasses) is one of the main controlling factors of magmatism in a volcanic system. Water diffusivity in silicate glasses depends on its own concentration. However, the mechanism causing those dependences has not been fully understood yet. In order to construct a general model for water diffusion in various silicate glasses, we performed water diffusion experiments in silica glass and proposed a new water diffusion model [Kuroda et al., 2015]. In the model, water diffusivity is controlled by the concentration of both main diffusion species (i.e. molecular water) and diffusion pathways, which are determined by the concentrations of hydroxyl groups and network modifier cations. The model well explains the water diffusivity in various silicate glasses from silica glass to basalt glass. However, pre-exponential factors of water diffusivity in various glasses show five orders of magnitude variations although the pre-exponential factor should ideally represent the jump frequency and the jump distance of molecular water and show a much smaller variation. Here, we attribute the large variation of pre-exponential factors to a glass structure dependence of activation energy for molecular water diffusion. It has been known that the activation energy depends on the water concentration [Nowak and Behrens, 1997]. The concentration of hydroxyls, which cut Si-O-Si network in the glass structure, increases with water concentration, resulting in lowering the activation energy for water diffusion probably due to more fragmented structure. Network modifier cations are likely to play the same role as water. With taking the effect of glass structure into account, we found that the variation of pre-exponential factors of water diffusivity in silicate glasses can be much smaller than the five orders of magnitude, implying that the diffusion of molecular water in silicate glasses is controlled by the same atomic process.
Johar, Kaid; Priya, Anusha; Wong-Riley, Margaret T T
2014-02-01
A major source of energy demand in neurons is the Na(+)/K(+)-ATPase pump that restores the ionic gradient across the plasma membrane subsequent to depolarizing neuronal activity. The energy comes primarily from mitochondrial oxidative metabolism, of which cytochrome c oxidase (COX) is a key enzyme. Recently, we found that all 13 subunits of COX are regulated by specificity (Sp) factors, and that the neuron-specific Sp4, but not Sp1 or Sp3, regulates the expression of key glutamatergic receptor subunits as well. The present study sought to test our hypothesis that Sp4 also regulates Na(+)/K(+)-ATPase subunit genes in neurons. By means of multiple approaches, including in silico analysis, electrophoretic mobility shift and supershift assays, chromatin immunoprecipitation, promoter mutational analysis, over-expression, and RNA interference studies, we found that Sp4, with minor contributions from Sp1 and Sp3, functionally regulate the Atp1a1, Atp1a3, and Atp1b1 subunit genes of Na(+)/K(+)-ATPase in neurons. Transcripts of all three genes were up-regulated by depolarizing KCl stimulation and down-regulated by the impulse blocker tetrodotoxin (TTX), indicating that their expression was activity-dependent. Silencing of Sp4 blocked the up-regulation of these genes induced by KCl, whereas over-expression of Sp4 rescued them from TTX-induced suppression. The effect of silencing or over-expressing Sp4 on primary neurons was much greater than those of Sp1 or Sp3. The binding sites of Sp factors on these genes are conserved among mice, rats and humans. Thus, Sp4 plays an important role in the transcriptional coupling of energy generation and energy consumption in neurons. © 2013 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.
Harinipriya, S; Sangaranarayanan, M V
2006-01-31
The evaluation of the free energy of activation pertaining to the electron-transfer reactions occurring at liquid/liquid interfaces is carried out employing a diffuse boundary model. The interfacial solvation numbers are estimated using a lattice gas model under the quasichemical approximation. The standard reduction potentials of the redox couples, appropriate inner potential differences, dielectric permittivities, as well as the width of the interface are included in the analysis. The methodology is applied to the reaction between [Fe(CN)6](3-/4-) and [Lu(biphthalocyanine)](3+/4+) at water/1,2-dichloroethane interface. The rate-determining step is inferred from the estimated free energy of activation for the constituent processes. The results indicate that the solvent shielding effect and the desolvation of the reactants at the interface play a central role in dictating the free energy of activation. The heterogeneous electron-transfer rate constant is evaluated from the molar reaction volume and the frequency factor.
Energy Expenditure During Extravehicular Activity Through Apollo
NASA Technical Reports Server (NTRS)
Paul, Heather L.
2012-01-01
Monitoring crew health during manned space missions has always been an important factor to ensure that the astronauts can complete the missions successfully and within safe physiological limits. The necessity of real-time metabolic rate monitoring during extravehicular activities (EVAs) came into question during the Gemini missions, when the energy expenditure required to complete EVA tasks exceeded the life support capabilities for cooling and humidity control and, as a result, crew members ended the EVAs fatigued and overworked. This paper discusses the importance of real-time monitoring of metabolic rate during EVAs, and provides a historical look at energy expenditure during EVAs through the Apollo Program.
Schnier, P D; Price, W D; Strittmatter, E F; Williams, E R
1997-08-01
The dissociation kinetics of protonated leucine enkephalin and its proton and alkali metal bound dimers were investigated by blackbody infrared radiative dissociation in a Fourier-transform mass spectrometer. From the temperature dependence of the unimolecular dissociation rate constants, Arrhenius activation parameters in the zero-pressure limit are obtained. Protonated leucine enkephalin dissociates to form b(4) and (M-H(2)O)(+) ions with an average activation energy (E(a)) of 1.1 eV and an A factor of 10(10.5) s(-1). The value of the A factor indicates that these dissociation processes are rearrangements. The b(4) ions subsequently dissociate to form a(4) ions via a process with a relatively high activation energy (1.3 eV), but one that is entropically favored. For the cationized dimers, the thermal stability decreases with increasing cation size, consistent with a simple electrostatic interaction in these noncovalent ion-molecule complexes. The E(a) and A factors are indistinguishable within experimental error with values of approximately 1.5 eV and 10(17) s(-1), respectively. Although not conclusive, results from master equation modeling indicate that all these BIRD processes, except for b(4) --> a(4), are in the rapid energy exchange limit. In this limit, the internal energy of the precursor ion population is given by a Boltzmann distribution and information about the energetics and dynamics of the reaction are obtained directly from the measured Arrhenius parameters.
Mandigout, Stéphane; Lacroix, Justine; Ferry, Béatrice; Vuillerme, Nicolas; Compagnat, Maxence; Daviet, Jean-Christophe
2017-12-01
Background In the subacute stroke phase, the monitoring of ambulatory activity and activities of daily life with wearable sensors may have relevant clinical applications. Do current commercially available wearable activity trackers allow us to objectively assess the energy expenditure of these activities? The objective of the present study was to compare the energy expenditure evaluated by indirect calorimetry during the course of a scenario consisting of everyday activities while estimating the energy expenditure using several commercialised wearable sensors in post-stroke patients (less than six months since stroke). Method Twenty-four patients (age 68.2 ± 13.9; post-stroke delay 34 ± 25 days) voluntarily participated in this study. Each patient underwent a scenario of various everyday tasks (transfer, walking, etc.). During the implementation, patients wore 14 wearable sensors (Armband, Actigraph GT3X, Actical, pedometer) to obtain an estimate of the energy expenditure. The actual energy expenditure was concurrently determined by indirect calorimetry. Results Except for the Armband worn on the non-plegic side, the results of our study show a significant difference between the energy expenditure values estimated by the various sensors and the actual energy expenditure when the scenario is considered as a whole. Conclusion The present results suggest that, for a series of everyday tasks, the wearable sensors underestimate the actual energy expenditure values in post-stroke patients in the subacute phase and are therefore not accurate. Several factors are likely to confound the results: types of activity, prediction equations, the position of the sensor and the hemiplegia side.
Effect of water quality and confounding factors on digestive enzyme activities in Gammarus fossarum.
Charron, L; Geffard, O; Chaumot, A; Coulaud, R; Queau, H; Geffard, A; Dedourge-Geffard, O
2013-12-01
The feeding activity and subsequent assimilation of the products resulting from food digestion allow organisms to obtain energy for growth, maintenance and reproduction. Among these biological parameters, we studied digestive enzymes (amylase, cellulase and trypsin) in Gammarus fossarum to assess the impact of contaminants on their access to energy resources. However, to enable objective assessment of a toxic effect of decreased water quality on an organisms' digestive capacity, it is necessary to establish reference values based on its natural variability as a function of changing biotic and abiotic factors. To limit the confounding influence of biotic factors, a caging approach with calibrated male organisms from the same population was used. This study applied an in situ deployment at 23 sites of the Rhone basin rivers, complemented by a laboratory experiment assessing the influence of two abiotic factors (temperature and conductivity). The results showed a small effect of conductivity on cellulase activity and a significant effect of temperature on digestive enzyme activity but only at the lowest temperature (7 °C). The experimental conditions allowed us to define an environmental reference value for digestive enzyme activities to select sites where the quality of the water impacted the digestive capacity of the organisms. In addition to the feeding rate, this study showed the relevance of digestive enzymes as biomarkers to be used as an early warning tool to reflect organisms' health and the chemical quality of aquatic ecosystems.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Oh, Se Jeong; Gu, Dong Ryun; Center for Metabolic Function Regulation
2016-06-17
Cytosolic malate dehydrogenase (malate dehydrogenase 1, MDH1) plays pivotal roles in the malate/aspartate shuttle that might modulate metabolism between the cytosol and mitochondria. In this study, we investigated the role of MDH1 in osteoclast differentiation and formation. MDH1 expression was induced by receptor activator of nuclear factor kappa-B ligand (RANKL) treatment. Knockdown of MDH1 by infection with retrovirus containing MDH1-specific shRNA (shMDH1) reduced mature osteoclast formation and bone resorption activity. Moreover, the expression of marker genes associated with osteoclast differentiation was downregulated by shMDH1 treatment, suggesting a role of MDH1 in osteoclast differentiation. In addition, intracellular ATP production was reducedmore » following the activation of adenosine 5′ monophosphate-activated protein kinase (AMPK), a cellular energy sensor and negative regulator of RANKL-induced osteoclast differentiation, in shMDH1-infected osteoclasts compared to control cells. In addition, the expression of c-Fos and nuclear factor of activated T-cells, cytoplasmic 1 (NFATc1), a critical transcription factor of osteoclastogenesis, was decreased with MDH1 knockdown during RANKL-mediated osteoclast differentiation. These findings provide strong evidence that MDH1 plays a critical role in osteoclast differentiation and function via modulation of the intracellular energy status, which might affect AMPK activity and NFATc1 expression.« less
Dolash, Karry; He, Meizi; Yin, Zenong; Sosa, Erica T
2015-04-01
Park features' association with physical activity among predominantly Hispanic communities is not extensively researched. The purpose of this study was to assess factors associated with park use and physical activity among park users in predominantly Hispanic neighborhoods. Data were collected across 6 parks and included park environmental assessments to evaluate park features, physical activity observations to estimate physical activity energy expenditure as kcal/kg/ minute per person, and park user interviews to assess motivators for park use. Quantitative data analysis included independent t tests and ANOVA. Thematic analysis of park user interviews was conducted collectively and by parks. Parks that were renovated had higher physical activity energy expenditure scores (mean = .086 ± .027) than nonrenovated parks (mean = .077 ± .028; t = -3.804; P < .01). Basketball courts had a significantly higher number of vigorously active park users (mean = 1.84 ± .08) than tennis courts (mean = .15 ± .01; F = 21.9, η(2) = 6.1%, P < .01). Thematic analysis of qualitative data revealed 4 emerging themes-motivation to be physically active, using the play spaces in the park, parks as the main place for physical activity, and social support for using parks. Renovations to park amenities, such as increasing basketball courts and trail availability, could potentially increase physical activity among low-socioeconomic-status populations.
Ershow, Abby G
2009-07-01
Recent epidemic increases in the U.S. prevalence of obesity and diabetes are a consequence of widespread environmental changes affecting energy balance and its regulation. These environmental changes range from exposure to endocrine disrupting pollutants to shortened sleep duration to physical inactivity to excess caloric intake. Overall, we need a better understanding of the factors affecting individual susceptibility and resistance to adverse exposures and behaviors and of determinants of individual response to treatment. Obesity and diabetes prevention will require responding to two primary behavioral risk factors: excess energy intake and insufficient energy expenditure. Adverse food environments (external, nonphysiological influences on eating behaviors) contribute to excess caloric intake but can be countered through behavioral and economic approaches. Adverse built environments, which can be modified to foster more physical activity, are promising venues for community-level intervention. Techniques to help people to modulate energy intake and increase energy expenditure must address their personal situations: health literacy, psychological factors, and social relationships. Behaviorally oriented translational research can help in developing useful interventions and environmental modifications that are tailored to individual needs. Copyright 2009 Diabetes Technology Society.
Sivakumar, S; Venkatesan, A; Soundhirarajan, P; Khatiwada, Chandra Prasad
2015-12-05
In this research, a chemical precipitation method was used to synthesize undoped and doped cadmium oxide nanoparticles and studied by TG-DTA, XRD, FT-IR, SEM, with EDX and antibacterial activities, respectively. The melting points, thermal stability and the kinetic parameters like entropy (ΔS), enthalpy (ΔH), Gibb's energy (ΔG), activation energy (E), frequency factor (A) were evaluated from TG-DTA measurements. X-ray diffraction analysis (XRD) brought out the information about the synthesized products exist in spherical in shape with cubic structure. The functional groups and band area of the samples were established by Fourier transform infrared (FT-IR) spectroscopy. The direct and indirect band gap energy of pure and doped samples were determined by UV-Vis-DRS. The surface morphological, elemental compositions and particles sizes were evaluated by scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS). Finally, antibacterial activities indicated the Gram-positive and Gram-negative bacteria are more active in transporter, dehydrogenize and periplasmic enzymatic activities of pure and doped samples. Copyright © 2015 Elsevier B.V. All rights reserved.
Relationship between tactics and energy expenditure according to level of experience in badminton.
Dieu, Olivier; Blondeau, Thomas; Vanhelst, Jérémy; Fardy, Paul S; Bui-Xuân, Gilles; Mikulovic, Jacques
2014-10-01
Research on racket sports has traditionally focused on expert players and has treated energy expenditure and tactics as independent factors. These prior studies could not assess how energy expenditure and tactics changed as a function of experience and skill. Here, the specific relationship between playing tactics and energy expenditure in badminton were assessed. Participants were classified into five stages of badminton experience on the basis of conative criteria: structural (physical abilities), technical (technical skills), and functional (tactics). The physical activity of 99 players (47 beginners, 15 intermediates, 30 advanced, and 7 experts) was measured using a three-axis accelerometer during a badminton set (21 points, no extra scoring). The results showed that physical activity (counts/sec.) ranged between about 115 (Stage 1) and 155 (Stage 5), and differed significantly across the conative stages. For Stages 2 and 4, defined by an increase in use of tactics, physical activity increased substantially. For Stage 3, defined by a decrease in use of tactics, physical activity decreased significantly. Thus, tactically-oriented play appears to be closely related to physical activity.
Rothman, S. M.; Mattson, M. P.
2013-01-01
During development of the nervous system, the formation of connections (synapses) between neurons is dependent upon electrical activity in those neurons, and neurotrophic factors produced by target cells play a pivotal role in such activity-dependent sculpting of the neural networks. A similar interplay between neurotransmitter and neurotrophic factor signaling pathways mediates adaptive responses of neural networks to environmental demands in adult mammals, with the excitatory neurotransmitter glutamate and brain-derived neurotrophic factor (BDNF) being particularly prominent regulators of synaptic plasticity throughout the central nervous system. Optimal brain health throughout the lifespan is promoted by intermittent challenges such as exercise, cognitive stimulation and dietary energy restriction, that subject neurons to activity-related metabolic stress. At the molecular level, such challenges to neurons result in the production of proteins involved in neurogenesis, learning and memory and neuronal survival; examples include proteins that regulate mitochondrial biogenesis, protein quality control, and resistance of cells to oxidative, metabolic and proteotoxic stress. BDNF signaling mediates up-regulation of several such proteins including the protein chaperone GRP-78, antioxidant enzymes, the cell survival protein Bcl-2, and the DNA repair enzyme APE1. Insufficient exposure to such challenges, genetic factors may conspire to impair BDNF production and/or signaling resulting in the vulnerability of the brain to injury and neurodegenerative disorders including Alzheimer’s, Parkinson’s and Huntington’s diseases. Further, BDNF signaling is negatively regulated by glucocorticoids. Glucocorticoids impair synaptic plasticity in the brain by negatively regulating spine density, neurogenesis and long-term potentiation, effects that are potentially linked to glucocorticoid regulation of BDNF. Findings suggest that BDNF signaling in specific brain regions mediates some of the beneficial effects of exercise and energy restriction on peripheral energy metabolism and the cardiovascular system. Collectively, the findings described in this article suggest the possibility of developing prescriptions for optimal brain health based on activity-dependent BDNF signaling. PMID:23079624
NASA Astrophysics Data System (ADS)
Vakulenko, Ihor; Myroshnychenko, Iuliia
2015-12-01
The research is devoted to the problem of the assessment of the integrated projects investment efficiency, energy saving and energy efficiency measures for social and municipal buildings within the course aimed at the reduction of the natural gas consumption and its replacement by alternative fuel types, that is important for a number of European countries, and Ukraine in particular. The objectives of the research are as follows: comparative assessment of the quality of integrated and element-by-element approaches to energy saving encompassing investment, environmental, social and organizational aspects; the formulation of practical recommendations to improve the efficiency of development and implementation of integrated programs in the field of energy saving and energy efficiency. It is proposed to use the methodology of system analysis with the elements of deduction that is practical and that allows to set key factors that influence the processes of energy replacement and energy efficiency increase, as well as factors that constrain them.
Schrama, J W; Bakker, G C
1999-12-01
Fermentable nonstarch polysaccharides (dietary fiber) affect energy retention in group-housed growing pigs by reducing physical activity. This study assessed the effects of fermentation and bulkiness of dietary carbohydrates on physical activity in relation to energy metabolism. Eight clusters of 14 pigs were fed one of four diets in a 2x2 factorial arrangement. Factors included 1) gastrointestinal fermentation and 2) dietary bulkiness. Contrasts in fermentation were created by exchanging gelatinized maize starch with raw potato starch on a volume basis. Bulkiness was altered by adding 15% milled wheat straw to the diets. Apart from these differences, amounts of other dietary ingredients fed to the pigs were similar. Pigs were housed in groups. Nitrogen and energy balances were measured per cluster during a 14-d period. Dietary bulkiness did not affect ME intake, heat production, or energy retention. Metabolizability decreased when maize starch was replaced with raw potato starch (P< .01), resulting in a lower energy retention on the potato starch diets (P<.01). However, the lower ME intake on the potato diets was partially compensated by a reduced energy expenditure on physical activity (P< .01), which was 17.6% lower than that of pigs fed the maize starch diets. Dietary bulkiness did not affect physical activity. The effect of fiber-rich diets (nonstarch polysaccharides) on activity in growing group-housed pigs seems to be related to fermentation in the gastrointestinal tract, and not to bulkiness (volume).
Dietary behaviour and socioeconomic position: the role of physical activity patterns.
Finger, Jonas D; Tylleskär, Thorkild; Lampert, Thomas; Mensink, Gert B M
2013-01-01
The positive association between education level and health outcomes can be partly explained by dietary behaviour. We investigated the associations between education and several indices of food intake and potential influencing factors, placing special emphasis on physical-activity patterns, using a representative sample of the German adult population. The German National Health Interview and Examination Survey 1998 (GNHIES98) involved 7,124 participants aged between 18 and 79. Complete information on the exposure (education) and outcome (nutrition) variables was available for 6,767 persons. The associations between 'education' and indices of 'sugar-rich food', 'fat-rich food', 'fruit-and-vegetable' and 'alcohol' intake were analysed separately for men and women using multivariate logistic regression analysis. Odds ratios (OR) of education level on nutrition outcomes were calculated and adjusted for age, region (former East/West Germany), occupation, income and other influencing factors such as physical activity indicators. Men and women with only a primary education had a more frequent intake of sugar-rich and fat-rich foods and a less frequent intake of fruit and vegetables and alcohol than people with a tertiary education. 'Physical work activity' partly explained the associations between education and sugar-rich food intake. The interference with physical work activity was stronger among men than women. No significant associations between education and energy-dense food intake were observed in the retirement-age group of persons aged 65+ and among persons with low energy expenditure. In Germany, adults with a low level of education report that they consume energy-dense foods more frequently - and fruit and vegetables and alcohol less frequently - than adults with a high education level. High levels of physical work activity among adults with a low education level may partly explain why they consume more energy-dense foods.
Assessing the Energy Consumption of Smartphone Applications
NASA Astrophysics Data System (ADS)
Abousaleh, Mustafa M.
Mobile devices are increasingly becoming essential in people's lives. The advancement in technology and mobility factor are allowing users to utilize mobile devices for communication, entertainment, financial planning, fitness tracking, etc. As a result, mobile applications are also becoming important factors contributing to user utility. However, battery capacity is the limiting factor impacting the quality of user experience. Hence, it is imperative to understand how much energy impact do mobile apps have on the system relative to other device activities. This thesis presents a systematic studying of the energy impact of mobile apps features. Time-series electrical current measurements are collected from 4 different modern smartphones. Statistical analysis methodologies are used to calculate the energy impact of each app feature by identifying and extracting mobile app-feature events from the overall current signal. In addition, the app overhead energy costs are also computed. Total energy consumption equations for each component is developed and an overall total energy consumption equation is presented. Minutes Lost (ML) of normal phone operations due to the energy consumption of the mobile app functionality is computed for cases where the mobile app is simulated to run on the various devices for 30 minutes. Tutela Technologies Inc. mobile app, NAT, is used for this study. NAT has two main features: QoS and Throughput. The impact of the QoS feature is indistinguishable, i.e. ML is zero, relative to other phone activities. The ML with only the TP feature enabled is on average 2.1 minutes. Enabling the GPS increases the ML on average to 11.5 minutes. Displaying the app GUI interface in addition to running the app features and enabling the GPS results in an average ML of 12.4 minutes. Amongst the various mobile app features and components studied, the GPS consumes the highest amount of energy. It is estimated that the GPS increases the ML by about 448%.
2016-01-01
The epidermal growth factor receptor (EGFR) is a dimeric membrane protein that regulates key aspects of cellular function. Activation of the EGFR is linked to changes in the conformation of the transmembrane (TM) domain, brought about by changes in interactions of the TM helices of the membrane lipid bilayer. Using an advanced computational approach that combines Coarse-Grained molecular dynamics and well-tempered MetaDynamics (CG-MetaD), we characterize the large-scale motions of the TM helices, simulating multiple association and dissociation events between the helices in membrane, thus leading to a free energy landscape of the dimerization process. The lowest energy state of the TM domain is a right-handed dimer structure in which the TM helices interact through the N-terminal small-X3-small sequence motif. In addition to this state, which is thought to correspond to the active form of the receptor, we have identified further low-energy states that allow us to integrate with a high level of detail a range of previous experimental observations. These conformations may lead to the active state via two possible activation pathways, which involve pivoting and rotational motions of the helices, respectively. Molecular dynamics also reveals correlation between the conformational changes of the TM domains and of the intracellular juxtamembrane domains, paving the way for a comprehensive understanding of EGFR signaling at the cell membrane. PMID:27459426
Lelimousin, Mickaël; Limongelli, Vittorio; Sansom, Mark S P
2016-08-24
The epidermal growth factor receptor (EGFR) is a dimeric membrane protein that regulates key aspects of cellular function. Activation of the EGFR is linked to changes in the conformation of the transmembrane (TM) domain, brought about by changes in interactions of the TM helices of the membrane lipid bilayer. Using an advanced computational approach that combines Coarse-Grained molecular dynamics and well-tempered MetaDynamics (CG-MetaD), we characterize the large-scale motions of the TM helices, simulating multiple association and dissociation events between the helices in membrane, thus leading to a free energy landscape of the dimerization process. The lowest energy state of the TM domain is a right-handed dimer structure in which the TM helices interact through the N-terminal small-X3-small sequence motif. In addition to this state, which is thought to correspond to the active form of the receptor, we have identified further low-energy states that allow us to integrate with a high level of detail a range of previous experimental observations. These conformations may lead to the active state via two possible activation pathways, which involve pivoting and rotational motions of the helices, respectively. Molecular dynamics also reveals correlation between the conformational changes of the TM domains and of the intracellular juxtamembrane domains, paving the way for a comprehensive understanding of EGFR signaling at the cell membrane.
van Deutekom, Arend W; Chinapaw, Mai Jm; Gademan, Maaike Gj; Twisk, Jos Wr; Gemke, Reinoud Jbj; Vrijkotte, Tanja Gm
2016-08-01
The purpose of this study was to examine the association of birth weight and infant growth with childhood autonomic nervous system (ANS) activity and to assess whether ANS activity mediates the associations of birth weight and infant growth with energy-balance-related behaviours, including energy intake, satiety response, physical activity and screen time. In 2089 children, we prospectively collected birth weight, infant growth defined as conditional weight and height gain between birth and 12 months and-at 5 years-indices of cardiac ANS activity and parent-reported energy-balance-related behaviours. A mediation analysis was conducted, based on MacKinnon's multivariate extension of the product-of-coefficients strategy. Birth weight and infant height gain were inversely associated with sympathetic, but not parasympathetic, activity at age 5. Infant weight gain was not associated with childhood ANS activity. Infant weight gain was predictive of increased childhood screen time and infant height gain of diminished childhood energy intake, but sympathetic activity did not mediate these associations. Low-birth-weight children have higher sympathetic activity, which is considered a risk factor for cardiovascular disease. Height gain in infancy seems to be beneficial for childhood sympathetic activity. However, sympathetic activity was no mediator of the associations of infant growth with childhood energy-balance-related behaviours. As individual differences in ANS activity predict increased risk of cardiovascular disease, these differences may offer insight into the early-life origins of chronic diseases and provide further basis for public health strategies to optimize birth weight and infant growth. © The Author 2016; all rights reserved. Published by Oxford University Press on behalf of the International Epidemiological Association.
Itoi, Aya; Yamada, Yosuke; Watanabe, Yoshiyuki; Kimura, Misaka
2012-12-01
The prevalence of childhood overweight and obesity has been shown to differ among regions, including rural-urban regional differences within nations. This study obtained simultaneous accelerometry-derived physical activity, 24 h activity, and food records to clarify the potential contributing factors to rural-urban differences in childhood overweight and obesity in Japan. Sixth-grade children (n = 227, 11-12 years old) from two urban elementary schools in Kyoto and four rural elementary schools in Tohoku participated in the study. The children were instructed to wear a pedometer that included a uniaxial accelerometer and, assisted by their parents, keep minute-by-minute 24 h activity and food records. For 12 children, the total energy expenditure was measured by the doubly labeled water method that was used to correct the Lifecorder-predicted activity energy expenditure and physical activity level. The overweight and obesity prevalence was significantly higher in rural than in urban children. The number of steps per day, activity energy expenditure, physical activity level, and duration of walking to school were significantly lower in rural than in urban children. In contrast, the reported energy intake did not differ significantly between the regions. The physical activity and duration of the walk to school were significantly correlated with body mass index. Rural children had a higher prevalence of overweight and obesity, and this may be at least partly caused by lower physical activity, especially less time spent walking to school, than urban children.
Trinchese, Giovanna; Cavaliere, Gina; Canani, Roberto Berni; Matamoros, Sebastien; Bergamo, Paolo; De Filippo, Chiara; Aceto, Serena; Gaita, Marcello; Cerino, Pellegrino; Negri, Rossella; Greco, Luigi; Cani, Patrice D; Mollica, Maria Pina
2015-11-01
Different nutritional components are able, by modulating mitochondrial function and gut microbiota composition, to influence body composition, metabolic homeostasis and inflammatory state. In this study, we aimed to evaluate the effects produced by the supplementation of different milks on energy balance, inflammatory state, oxidative stress and antioxidant/detoxifying enzyme activities and to investigate the role of the mitochondrial efficiency and the gut microbiota in the regulation of metabolic functions in an animal model. We compared the intake of human milk, gold standard for infant nutrition, with equicaloric supplementation of donkey milk, the best substitute for newborns due to its nutritional properties, and cow milk, the primary marketed product. The results showed a hypolipidemic effect produced by donkey and human milk intake in parallel with enhanced mitochondrial activity/proton leakage. Reduced mitochondrial energy efficiency and proinflammatory signals (tumor necrosis factor α, interleukin-1 and lipopolysaccharide levels) were associated with a significant increase of antioxidants (total thiols) and detoxifying enzyme activities (glutathione-S-transferase, NADH quinone oxidoreductase) in donkey- and human milk-treated animals. The beneficial effects were attributable, at least in part, to the activation of the nuclear factor erythroid-2-related factor-2 pathway. Moreover, the metabolic benefits induced by human and donkey milk may be related to the modulation of gut microbiota. In fact, milk treatments uniquely affected the proportions of bacterial phyla and genera, and we hypothesized that the increased concentration of fecal butyrate in human and donkey milk-treated rats was related to the improved lipid and glucose metabolism and detoxifying activities. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.
Accuracy of a novel multi-sensor board for measuring physical activity and energy expenditure
Lester, Jonathan; Migotsky, Sean; Goh, Jorming; Higgins, Lisa; Borriello, Gaetano
2011-01-01
The ability to relate physical activity to health depends on accurate measurement. Yet, none of the available methods are fully satisfactory due to several factors. This study examined the accuracy of a multi-sensor board (MSB) that infers activity types (sitting, standing, walking, stair climbing, and running) and estimates energy expenditure in 57 adults (32 females) 39.2 ± 13.5 years. In the laboratory, subjects walked and ran on a treadmill over a select range of speeds and grades for 3 min each (six stages in random order) while connected to a stationary calorimeter, preceded and followed by brief sitting and standing. On a different day, subjects completed scripted activities in the field connected to a portable calorimeter. The MSB was attached to a strap at the right hip. Subjects repeated one condition (randomly selected) on the third day. Accuracy of inferred activities compared with recorded activities (correctly identified activities/total activities × 100) was 97 and 84% in the laboratory and field, respectively. Absolute accuracy of energy expenditure [100 – absolute value (kilocalories MSB – kilocalories calorimeter/kilocalories calorimeter) × 100] was 89 and 76% in the laboratory and field, the later being different (P < 0.05) from the calorimeter. Test–retest reliability for energy expenditure was significant in both settings (P < 0.0001; r = 0.97). In general, the MSB provides accurate measures of activity type in laboratory and field settings and energy expenditure during treadmill walking and running although the device underestimates energy expenditure in the field. PMID:21249383
USDA-ARS?s Scientific Manuscript database
Insulin acts as the major regulator of the fasting-to-fed metabolic transition by altering substrate metabolism, promoting energy storage, and helping activate protein synthesis. In addition to its glucoregulatory and other metabolic properties, insulin can also act as a growth factor. The metabolic...
Sorensen, Mathew D; Chi, Thomas; Shara, Nawar M; Wang, Hong; Hsi, Ryan S; Orchard, Tonya; Kahn, Arnold J; Jackson, Rebecca D; Miller, Joe; Reiner, Alex P; Stoller, Marshall L
2014-02-01
Obesity is a strong risk factor for nephrolithiasis, but the role of physical activity and caloric intake remains poorly understood. We evaluated this relationship in 84,225 women with no history of stones as part of the Women's Health Initiative Observational Study, a longitudinal, prospective cohort of postmenopausal women enrolled from 1993 to 1998 with 8 years' median follow-up. The independent association of physical activity (metabolic equivalents [METs]/wk), calibrated dietary energy intake, and body mass index (BMI) with incident kidney stone development was evaluated after adjustment for nephrolithiasis risk factors. Activity intensity was evaluated in stratified analyses. Compared with the risk in inactive women, the risk of incident stones decreased by 16% in women with the lowest physical activity level (adjusted hazard ratio [aHR], 0.84; 95% confidence interval [95% CI], 0.74 to 0.97). As activity increased, the risk of incident stones continued to decline until plateauing at a decrease of approximately 31% for activity levels ≥10 METs/wk (aHR, 0.69; 95% CI, 0.60 to 0.79). Intensity of activity was not associated with stone formation. As dietary energy intake increased, the risk of incident stones increased by up to 42% (aHR, 1.42; 95% CI, 1.02 to 1.98). However, intake <1800 kcal/d did not protect against stone formation. Higher BMI category was associated with increased risk of incident stones. In summary, physical activity may reduce the risk of incident kidney stones in postmenopausal women independent of caloric intake and BMI, primarily because of the amount of activity rather than exercise intensity. Higher caloric intake further increases the risk of incident stones.
Catalytic pyrolysis characteristics of scrap printed circuit boards by TG-FTIR.
Zhao, Chunhu; Zhang, Xiaoping; Shi, Lin
2017-03-01
In the present work, pyrolysis and catalytic pyrolysis of waste printed circuit boards (WPCBs) was carried out in the coupling of Thermo Gravimetric Analysis and Fourier Transform Infrared Spectroscopy (TG-FTIR) under nitrogen atmosphere. The reaction temperature was increased from 30 to 700°C, while the heating rates were varied from 10 to 40°C/min. Experimental results show that the effect of catalyst on the WPCBs particles pyrolysis was significance. Compared with another two combustion-supporting agents (MgO, CaO), the whole pyrolysis process was optimized when the catalyst ZSM-5 was added into the WPCBs particles. The distributed activation energy model (DAEM) was used to analyze the kinetic parameters of the WPCBs pyrolysis. It was found that values of frequency factor (k 0 ) changed with different activation energy (E) values during pyrolysis process. The activation energy values range from 129.15 to 280.53kJ/mol, and the frequency factor values range from 9.02×10 10 to 4.21×10 22 s -1 . The generated major products for the catalytic pyrolysis of WPCBs were H 2 , CO 2 , CO, H 2 O, phenols and aromatics. Copyright © 2016 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Izie Adiana Abidin, Nur; Aminuddin, Eeydzah; Zakaria, Rozana; Mazzuana Shamsuddin, Siti; Sahamir, Shaza Rina; Shahzaib, Jam; Nafis Abas, Darul
2018-04-01
Campus university building is the Higher Learning Institution (HLI) involves complex activities and operations, conserving the energy has become paramount important. There are several efforts taken by universities to improve its current energy use such as policy development, education, and adaption of energy conservation solution through retrofitting. This paper aims to highlight the importance of the criteria affecting in retrofitting of existing buildings with clean energy in order to achieve zero energy balance in buildings. The focus is given to the development of criteria for solar photovoltaic (solar PV), wind turbines and small-scale hydropower. A questionnaire survey was employed and distributed to the green building expert practitioner. Factor Analysis, Factor Score, and Weightage Factor were adapted as a method of analysis in order to produce the final result with weightage output for prioritization and ranking of the relevant criteria. The result performed assists to provide the stakeholders an overview of the important criteria that should be considered especially during the decision making to retrofit the existing buildings with clean energy resources. The criteria developed are also to establish a structured decision-making process and to ensure the selection of the decision or alternatives achieve the desired outcome.
ERIC Educational Resources Information Center
School Science Review, 1982
1982-01-01
Presents procedures, demonstrations, activities, and teaching suggestions on topics appropriate for middle school science including a simple electrolysis cell, conversion factors, energy, solubilities of salts, condensers, and a worksheet for studying coppice woodlands. (DC)
Neural Representations of Physics Concepts.
Mason, Robert A; Just, Marcel Adam
2016-06-01
We used functional MRI (fMRI) to assess neural representations of physics concepts (momentum, energy, etc.) in juniors, seniors, and graduate students majoring in physics or engineering. Our goal was to identify the underlying neural dimensions of these representations. Using factor analysis to reduce the number of dimensions of activation, we obtained four physics-related factors that were mapped to sets of voxels. The four factors were interpretable as causal motion visualization, periodicity, algebraic form, and energy flow. The individual concepts were identifiable from their fMRI signatures with a mean rank accuracy of .75 using a machine-learning (multivoxel) classifier. Furthermore, there was commonality in participants' neural representation of physics; a classifier trained on data from all but one participant identified the concepts in the left-out participant (mean accuracy = .71 across all nine participant samples). The findings indicate that abstract scientific concepts acquired in an educational setting evoke activation patterns that are identifiable and common, indicating that science education builds abstract knowledge using inherent, repurposed brain systems. © The Author(s) 2016.
Subcontracted activities related to TES for building heating and cooling
NASA Technical Reports Server (NTRS)
Martin, J.
1980-01-01
The subcontract program elements related to thermal energy storage for building heating and cooling systems are outlined. The following factors are included: subcontracts in the utility load management application area; life and stability testing of packaged low cost energy storage materials; and development of thermal energy storage systems for residential space cooling. Resistance storage heater component development, demonstration of storage heater systems for residential applications, and simulation and evaluation of latent heat thermal energy storage (heat pump systems) are also discussed. Application of thermal energy storage for solar application and twin cities district heating are covered including an application analysis and technology assessment of thermal energy storage.
The spatial and temporal evolution of carbon emissions drivers in the United States
NASA Astrophysics Data System (ADS)
Baldwin, James George
This dissertation addresses two important environmental policy questions: how has the structure of the drivers of U.S. carbon dioxide ( CO2) emissions evolved through time and across regions, and what role have economic forces played in shaping these factors? First, prior research on the drivers of CO2 emissions at the state level and the use of index number decomposition techniques to analyze CO2's fossil-fuel precursors are reviewed. Second, a novel Kaya identity decomposition method is developed which partitions the historical series of energy-related emissions into five factors: the CO2 intensity of energy use, the energy intensity of economic activity, changes in economic structure, affluence and population growth. While aggregate growth in emissions has been driven almost entirely by increases in population and affluence, the results demonstrate significant regional heterogeneity. Third, the influences of affluence and population, along with regional energy prices, investment patterns, and weather, on CO 2 intensity, energy intensity and structural change, are analyzed statistically. The contributions of carbon-intensive fuels exhibit significant but inelastic relationships to income, capital availability and fossil fuel prices. Contributions due to energy intensity exhibit significant and negative relationships to all factors examined excluding petroleum and electricity prices. Energy intensity is inelastic in the short run but elastic in the long run to income, weather, petroleum and coal prices. Contributions due to economic structure are significant but inelastic to income, cool weather and petroleum price. The contribution of energy intensity to emissions growth is more strongly influenced by increases in personal income than by value added, suggesting that consumption rather than production plays the more important role. Controlling for the scale of economic activity, larger populations, faster rates of investment and greater capital availability are associated with lower energy intensity. The low elasticity of carbon intensity, energy intensity and structural change with respect to trends in the economy imply a need for a fundamental shift in U.S. energy use and production. The implication of these findings is that current economic and demographic trends are unlikely to lead to declines in emissions, and that policy intervention will be required to achieve emissions reductions.
Pieters, Marlien; Oosthuizen, Welma; Jerling, Johann C; Loots, Du Toit; Mukuddem-Petersen, Janine; Hanekom, Susanna M
2005-09-01
We investigated the effect of a high walnut and cashew diet on haemostatic variables in people with the metabolic syndrome. Factor analysis was used to determine how the haemostatic variables cluster with other components of the metabolic syndrome and multiple regression to determine possible predictors. This randomized, control, parallel, controlled-feeding trial included 68 subjects who complied with the Third National Cholesterol Education Program Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol criteria. After a 3-week run-in following the control diet, subjects were divided into three groups receiving either walnuts or cashews (20 energy%) or a control diet for 8 weeks. The nut intervention had no significant effect on von Willebrand factor antigen, fibrinogen, factor VII coagulant activity, plasminogen activator inhibitor 1 activity, tissue plasminogen activator activity or thrombin activatable fibrinolysis inhibitor. Statistically, fibrinogen clustered with the body-mass-correlates and acute phase response factors, and factor VII coagulant activity clustered with high-density lipoprotein cholesterol (HDL-C). Tissue plasminogen activator activity, plasminogen activator inhibitor 1 activity and von Willebrand factor antigen clustered into a separate endothelial function factor. HDL-C and markers of obesity were the strongest predictors of the haemostatic variables. We conclude that high walnut and cashew diets did not influence haemostatic factors in this group of metabolic syndrome subjects. The HDL-C increase and weight loss may be the main focus of dietary intervention for the metabolic syndrome. Furthermore, diet composition may have only limited effects if weight loss is not achieved.
Smith, Aaron G; Muscat, George E O
2005-10-01
Skeletal muscle is a major mass peripheral tissue that accounts for approximately 40% of the total body mass and a major player in energy balance. It accounts for >30% of energy expenditure, is the primary tissue of insulin stimulated glucose uptake, disposal, and storage. Furthermore, it influences metabolism via modulation of circulating and stored lipid (and cholesterol) flux. Lipid catabolism supplies up to 70% of the energy requirements for resting muscle. However, initial aerobic exercise utilizes stored muscle glycogen but as exercise continues, glucose and stored muscle triglycerides become important energy substrates. Endurance exercise increasingly depends on fatty acid oxidation (and lipid mobilization from other tissues). This underscores the importance of lipid and glucose utilization as an energy source in muscle. Consequently skeletal muscle has a significant role in insulin sensitivity, the blood lipid profile, and obesity. Moreover, caloric excess, obesity and physical inactivity lead to skeletal muscle insulin resistance, a risk factor for the development of type II diabetes. In this context skeletal muscle is an important therapeutic target in the battle against cardiovascular disease, the worlds most serious public health threat. Major risk factors for cardiovascular disease include dyslipidemia, hypertension, obesity, sedentary lifestyle, and diabetes. These risk factors are directly influenced by diet, metabolism and physical activity. Metabolism is largely regulated by nuclear hormone receptors which function as hormone regulated transcription factors that bind DNA and mediate the patho-physiological regulation of gene expression. Metabolism and activity, which directly influence cardiovascular disease risk factors, are primarily driven by skeletal muscle. Recently, many nuclear receptors expressed in skeletal muscle have been shown to improve glucose tolerance, insulin resistance, and dyslipidemia. Skeletal muscle and nuclear receptors are rapidly emerging as critical targets in the battle against cardiovascular disease risk factors. Understanding the function of nuclear receptors in skeletal muscle has enormous pharmacological utility for the treatment of cardiovascular disease. This review focuses on the molecular regulation of metabolism by nuclear receptors in skeletal muscle in the context of dyslipidemia and cardiovascular disease.
Marteinson, Sarah C; Marcogliese, David J; Verreault, Jonathan
2017-10-01
Daily energy expenditure (DEE) in animals is influenced by many factors although the impact of stressors remains largely unknown. The objective of this study was to determine how multiple physiological stressors (parasite infection and contaminant exposure) and natural challenges (energy-demanding activities and weather conditions) may affect DEE in nesting ring-billed gulls (Larus delawarensis) exposed to high concentrations of persistent organic contaminants (POPs). Physical activity, temperature, gastrointestinal parasitic worm abundance, relative spleen mass, plasma thyroid hormone levels and liver concentrations of POPs were determined; field metabolic rate (FMR) was used as a measure of DEE. For females, FMR was best explained by the percent of time spent in nest-site attendance and exposure to temperatures below their lower critical limit (65% of variation); 32% was also explained by relative spleen mass. In males, FMR was best explained by the number of hours spent in nest site attendance and either relative spleen mass or liver concentrations of tetra-brominated diphenyl ethers (tetra-BDEs) (55% of variation). Relative spleen mass, as an important factor relating to FMR, was best explained by models with a combination of parasite abundance (Diplostomum for females and Eucoleus for males) in a negative relationship, and liver POP concentrations (p,p'-DDE for females and tetra-BDEs for males) in a positive relationship (34%, 55% of variation for females and males, respectively). This study demonstrates that immune activity may be an important factor affecting energy expenditure in ring-billed gulls, and that contaminants and parasite abundance may have both a direct and/or indirect influence on FMR. Copyright © 2017 Elsevier Inc. All rights reserved.
Energy scavenging sources for biomedical sensors.
Romero, E; Warrington, R O; Neuman, M R
2009-09-01
Energy scavenging has increasingly become an interesting option for powering electronic devices because of the almost infinite lifetime and the non-dependence on fuels for energy generation. Moreover, the rise of wireless technologies promises new applications in medical monitoring systems, but these still face limitations due to battery lifetime and size. A trade-off of these two factors has typically governed the size, useful life and capabilities of an autonomous system. Energy generation from sources such as motion, light and temperature gradients has been established as commercially viable alternatives to batteries for human-powered flashlights, solar calculators, radio receivers and thermal-powered wristwatches, among others. Research on energy harvesting from human activities has also addressed the feasibility of powering wearable or implantable systems. Biomedical sensors can take advantage of human-based activities as the energy source for energy scavengers. This review describes the state of the art of energy scavenging technologies for powering sensors and instrumentation of physiological variables. After a short description of the human power and the energy generation limits, the different transduction mechanisms, recent developments and challenges faced are reviewed and discussed.
USDA-ARS?s Scientific Manuscript database
Suboptimal nutrient intake represents a limiting factor for growth and long-term survival of low-birth weight infants. The objective of this study was to determine if in neonates who can consume only 70 % of their protein and energy requirements for 8 days, enteral leucine supplementation will upreg...
NASA Astrophysics Data System (ADS)
Lichtenberg, Dennis L.
During this period some important breakthroughs were accomplished in understanding the relationships between molecular ionization energies and bond energies in transition metal complexes, in understanding the electronic factors of carbon-hydrogen bond activation by transition metals, in characterizing small molecule bonding interactions with transition metals, and in investigating intermolecular interactions in thin films of transition metal complexes. The formal relationship between measured molecular ionization energies and thermodynamic bond dissociation energies was developed into a single equation which unifies the treatment of covalent bonds, ionic bonds, and partially ionic bonds. The relationship was used to clarify the fundamental thermodynamic information relating to metal-hydrogen, metal-alkyl, and metal-metal bond energies. The ionization energies were also used to correlate the rates of carbonyl substitution reactions of (eta(sup 5)-C5H4X)Rh(CO)2 complexes, and to reveal the factors that control the stability of the transition state. The investigations of the fundamental interactions of C-H sigma and sigma* orbitals metals were continued with study of eta(sup 3)-1-methylallyl metal complexes. Direct observation and measurement of the stabilization energy provided by the agostic interaction of the C-H bond with the metal was obtained. The ability to observe the electronic effects of intermolecular interactions by comparing the ionizations of metal complexes in the gas phase with the ionizations of thin solid organometallic films prepared in ultra-high vacuum was established. Most significantly, the scanning tunneling microscope imaging of these thin films was accomplished.
Symmetry breaking in the zero-energy Landau level in bilayer graphene.
Zhao, Y; Cadden-Zimansky, P; Jiang, Z; Kim, P
2010-02-12
The quantum Hall effect near the charge neutrality point in bilayer graphene is investigated in high magnetic fields of up to 35 T using electronic transport measurements. In the high-field regime, the eightfold degeneracy in the zero-energy Landau level is completely lifted, exhibiting new quantum Hall states corresponding to filling factors nu=0, 1, 2, and 3. Measurements of the activation energy gaps for the nu=2 and 3 filling factors in tilted magnetic fields exhibit no appreciable dependence on the in-plane magnetic field, suggesting that these Landau level splittings are independent of spin. In addition, measurements taken at the nu=0 charge neutral point show that, similar to single layer graphene, the bilayer becomes insulating at high fields.
Bao, Chengzhen; Chai, Pengfei; Lin, Hongbo; Zhang, Zhenyu; Ye, Zhenhua; Gu, Mengjia; Lu, Huaichu; Shen, Peng; Jin, Mingjuan; Wang, Jianbing; Chen, Kun
2016-12-01
Recently, air pollution has attracted a substantial amount of attention in China, which can be influenced by a variety of factors, but the association between air pollution and human activity is not quite clear. Based on real-time online data (January 1, 2014, to December 31, 2014) of air pollution and meteorology reported by official sites, and demographic, economic, and environmental reform data in a statistical yearbook, the influences of meteorological factors (temperature, relative humidity, precipitation intensity, and wind force) and human activities on PM 2.5 pollution were explored. After correlation analysis, logistic regression analysis, and a nonparametric test, weak negative correlations between temperature and PM 2.5 pollution were found. In most cases, festival and morning peak hours were protection and risk factors of PM 2.5 pollution, respectively. In addition, government actions, such as an afforestation project and increasing financial expenditure for energy saving and environmental protection, could greatly contribute to alleviating pollution of PM 2.5 . The findings could help officials formulate effective laws and regulations, and then PM 2.5 pollution related to the pattern of human activity would be ameliorated. Most of the time, festival and morning peak hours are protection and risk factors for PM 2.5 pollution, respectively. Increasing the percentage of afforestation area and financial expenditure for energy saving and environmental protection could significantly reduce PM 2.5 pollution. The findings can help officials formulate effective laws and regulations, and then PM 2.5 pollution related to the pattern of human activity, especially government action, will be ameliorated.
NASA Astrophysics Data System (ADS)
Herrera, L.
2018-02-01
We put forward a new definition of complexity, for static and spherically symmetric self-gravitating systems, based on a quantity, hereafter referred to as complexity factor, that appears in the orthogonal splitting of the Riemann tensor, in the context of general relativity. We start by assuming that the homogeneous (in the energy density) fluid, with isotropic pressure is endowed with minimal complexity. For this kind of fluid distribution, the value of complexity factor is zero. So, the rationale behind our proposal for the definition of complexity factor stems from the fact that it measures the departure, in the value of the active gravitational mass (Tolman mass), with respect to its value for a zero complexity system. Such departure is produced by a specific combination of energy density inhomogeneity and pressure anisotropy. Thus, zero complexity factor may also be found in self-gravitating systems with inhomogeneous energy density and anisotropic pressure, provided the effects of these two factors, on the complexity factor, cancel each other. Some exact interior solutions to the Einstein equations satisfying the zero complexity criterium are found, and prospective applications of this newly defined concept, to the study of the structure and evolution of compact objects, are discussed.
Factors Influencing Energy Use and Carbon Emissions in China
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fisher-Vanden, Karen; Jefferson, Gary
This research project was designed to fill a critical void in our understanding of the state of energy research and innovation in China. It seeks to provide a comprehensive review and accounting of the various elements of the Chinese government and non-governmental sectors (commercial, university, research institutes) that are engaged in energy-related R&D and various aspects of energy innovation, including specific programs and projects designed to promote renewable energy innovation and energy conservation. The project provides an interrelated descriptive, statistical, and econometric account of China's overall energy innovation activities and capabilities, spanning the full economy with a particular focus onmore » the dynamic industrial sector.« less
Li, Yan; Li, Xiang; Ma, Weiya; Dong, Zigang
2014-08-12
The epidermal growth factor receptor (EGFR) is aberrantly activated in various cancer cells and an important target for cancer treatment. Deep understanding of EGFR conformational changes between the active and inactive states is of pharmaceutical interest. Here we present a strategy combining multiply targeted molecular dynamics simulations, unbiased molecular dynamics simulations, and Bayesian clustering to investigate transition pathways during the activation/inactivation process of EGFR kinase domain. Two distinct pathways between the active and inactive forms are designed, explored, and compared. Based on Bayesian clustering and rough two-dimensional free energy surfaces, the energy-favorable pathway is recognized, though DFG-flip happens in both pathways. In addition, another pathway with different intermediate states appears in our simulations. Comparison of distinct pathways also indicates that disruption of the Lys745-Glu762 interaction is critically important in DFG-flip while movement of the A-loop significantly facilitates the conformational change. Our simulations yield new insights into EGFR conformational transitions. Moreover, our results verify that this approach is valid and efficient in sampling of protein conformational changes and comparison of distinct pathways.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Yin, H.; Gao, M.; Wei, R.P.
1995-01-01
To better understand environmentally assisted crack growth (SCG) in yttria stabilized zirconia, experimental studies were undertaken to characterize the kinetics of crack growth and the associated stress/moisture induced phase transformation in ZrO[sub 2] + 3 mol% Y[sub 2]O[sub 3] (3Y-TZP) in water, dry nitrogen and toluene from 3 to 70 C. The results showed that crack growth in water depended strongly on stress intensity factor (K[sub 1]) and temperature (T) and involved the transformation of a thin layer of material near the crack tip from the tetragonal (t) to the monoclinic (m) phase. These results, combined with literature data onmore » moisture-induced phase transformation, suggested that crack growth enhancement by water is controlled by the rate of this transformation and reflects the environmental cracking susceptibility of the transformed m-phase. A model was developed to link subcritical crack growth (SCG) rate to the kinetics of t [yields] m phase transformation. The SCG rate is expressed as an exponential function of stress-free activation energy, a stress-dependent contribution in terms of the mode 1 stress intensity factor K[sub I] and actuation volume, and temperature. The stress-free activation energies for water and the inert environments were determined to be 82 [+-] 3 and 169 [+-] 4 kJ/mol, respectively, at the 95% confidence level, and the corresponding activation volumes were 14 and 35 unit cells. The decreases in activation energy and activation volume may be attributed to a change in surface energy by water.« less
Atmospheric energy for subsurface life on Mars?
NASA Technical Reports Server (NTRS)
Weiss, B. P.; Yung, Y. L.; Nealson, K. H.
2000-01-01
The location and density of biologically useful energy sources on Mars will limit the biomass, spatial distribution, and organism size of any biota. Subsurface Martian organisms could be supplied with a large energy flux from the oxidation of photochemically produced atmospheric H(2) and CO diffusing into the regolith. However, surface abundance measurements of these gases demonstrate that no more than a few percent of this available flux is actually being consumed, suggesting that biological activity driven by atmospheric H(2) and CO is limited in the top few hundred meters of the subsurface. This is significant because the available but unused energy is extremely large: for organisms at 30-m depth, it is 2,000 times previous estimates of hydrothermal and chemical weathering energy and far exceeds the energy derivable from other atmospheric gases. This also implies that the apparent scarcity of life on Mars is not attributable to lack of energy. Instead, the availability of liquid water may be a more important factor limiting biological activity because the photochemical energy flux can only penetrate to 100- to 1,000-m depth, where most H(2)O is probably frozen. Because both atmospheric and Viking lander soil data provide little evidence for biological activity, the detection of short-lived trace gases will probably be a better indicator of any extant Martian life.
Atmospheric energy for subsurface life on Mars?
Weiss, B P; Yung, Y L; Nealson, K H
2000-02-15
The location and density of biologically useful energy sources on Mars will limit the biomass, spatial distribution, and organism size of any biota. Subsurface Martian organisms could be supplied with a large energy flux from the oxidation of photochemically produced atmospheric H(2) and CO diffusing into the regolith. However, surface abundance measurements of these gases demonstrate that no more than a few percent of this available flux is actually being consumed, suggesting that biological activity driven by atmospheric H(2) and CO is limited in the top few hundred meters of the subsurface. This is significant because the available but unused energy is extremely large: for organisms at 30-m depth, it is 2,000 times previous estimates of hydrothermal and chemical weathering energy and far exceeds the energy derivable from other atmospheric gases. This also implies that the apparent scarcity of life on Mars is not attributable to lack of energy. Instead, the availability of liquid water may be a more important factor limiting biological activity because the photochemical energy flux can only penetrate to 100- to 1,000-m depth, where most H(2)O is probably frozen. Because both atmospheric and Viking lander soil data provide little evidence for biological activity, the detection of short-lived trace gases will probably be a better indicator of any extant Martian life.
Isothermal reduction kinetics of Panzhihua ilmenite concentrate under 30vol% CO-70vol% N2 atmosphere
NASA Astrophysics Data System (ADS)
Zhang, Ying-yi; Lü, Wei; Lü, Xue-wei; Li, Sheng-ping; Bai, Chen-guang; Song, Bing; Han, Ke-xi
2017-03-01
The reduction of ilmenite concentrate in 30vol% CO-70vol% N2 atmosphere was characterized by thermogravimetric and differential thermogravimetric (TG-DTG) analysis methods at temperatures from 1073 to 1223 K. The isothermal reduction results show that the reduction process comprised two stages; the corresponding apparent activation energy was obtained by the iso-conversional and model-fitting methods. For the first stage, the effect of temperature on the conversion degree was not obvious, the phase boundary chemical reaction was the controlling step, with an apparent activation energy of 15.55-40.71 kJ·mol-1. For the second stage, when the temperatures was greater than 1123 K, the reaction rate and the conversion degree increased sharply with increasing temperature, and random nucleation and subsequent growth were the controlling steps, with an apparent activation energy ranging from 182.33 to 195.95 kJ·mol-1. For the whole reduction process, the average activation energy and pre-exponential factor were 98.94-118.33 kJ·mol-1 and 1.820-1.816 min-1, respectively.
Bisquert, Juan; Henn, François; Giuntini, Jean-Charles
2005-03-01
Strong changes in relaxation rates observed at the glass transition region are frequently explained in terms of a physical singularity of the molecular motions. We show that the unexpected trends and values for activation energy and preexponential factor of the relaxation time tau, obtained at the glass transition from the analysis of the thermally stimulated current signal, result from the use of the Arrhenius law for treating the experimental data obtained in nonstationary experimental conditions. We then demonstrate that a simple model of structural relaxation based on a time dependent configurational entropy and Adam-Gibbs relaxation time is sufficient to explain the experimental behavior, without invoking a kinetic singularity at the glass transition region. The pronounced variation of the effective activation energy appears as a dynamic signature of entropy relaxation that governs the change of relaxation time in nonstationary conditions. A connection is demonstrated between the peak of apparent activation energy measured in nonequilibrium dielectric techniques, with the overshoot of the dynamic specific heat that is obtained in calorimetry techniques.
Input-current shaped ac to dc converters
NASA Technical Reports Server (NTRS)
1986-01-01
The problem of achieving near unity power factor while supplying power to a dc load from a single phase ac source of power is examined. Power processors for this application must perform three functions: input current shaping, energy storage, and output voltage regulation. The methods available for performing each of these three functions are reviewed. Input current shaping methods are either active or passive, with the active methods divided into buck-like and boost-like techniques. In addition to large reactances, energy storage methods include resonant filters, active filters, and active storage schemes. Fast voltage regulation can be achieved by post regulation or by supplementing the current shaping topology with an extra switch. Some indications of which methods are best suited for particular applications concludes the discussion.
Thermal behavior and compatibility study of dihydroxylammonium 3,4-dinitraminofurazan
NASA Astrophysics Data System (ADS)
Huang, Haifeng; Shi, Yameng; Yu, Yao; Yang, Jun
2018-04-01
A large number of nitramino-featured energetic salts have been reported and some of them show promising properties. Among them, the dihydroxylammonium 3,4-dinitraminofurazan (HADNAF) is easy to synthesize and shows high calculated detonation performances and acceptable thermal stability. The non-isothermal kinetics parameters of HADNAF including the apparent activation energy (E) and pre-exponential factor (A) of the exothermic decomposition reaction, and activation entropy (ΔS≠), activation enthalpy (ΔH≠), activation Gibbs free energy (ΔG≠) at TP0 of the reaction and the critical temperature of thermal explosion (Tb) were obtained by Kissinger's and Ozawa's method, respectively. Additionally, the compatibility of HADNAF with other materials (e.g. TNT, RDX, HMX, B, Mg) was tested by DSC method.
Posture and activity recognition and energy expenditure prediction in a wearable platform.
Sazonova, Nadezhda; Browning, Raymond; Melanson, Edward; Sazonov, Edward
2014-01-01
The use of wearable sensors coupled with the processing power of mobile phones may be an attractive way to provide real-time feedback about physical activity and energy expenditure (EE). Here we describe use of a shoe-based wearable sensor system (SmartShoe) with a mobile phone for real-time prediction and display of time spent in various postures/physical activities and the resulting EE. To deal with processing power and memory limitations of the phone, we introduce new algorithms that require substantially less computational power. The algorithms were validated using data from 15 subjects who performed up to 15 different activities of daily living during a four-hour stay in a room calorimeter. Use of Multinomial Logistic Discrimination (MLD) for posture and activity classification resulted in an accuracy comparable to that of Support Vector Machines (SVM) (90% vs. 95%-98%) while reducing the running time by a factor of 190 and reducing the memory requirement by a factor of 104. Per minute EE estimation using activity-specific models resulted in an accurate EE prediction (RMSE of 0.53 METs vs. RMSE of 0.69 METs using previously reported SVM-branched models). These results demonstrate successful implementation of real-time physical activity monitoring and EE prediction system on a wearable platform.
Horesh, Sefi J A; Sivan, Jaim; Rosenstrauch, Avi; Tesler, Itay; Degen, A Allan; Kam, Michael
2017-02-01
Sit-and-wait ambushing and active hunting are two strategies used by predators to capture prey. In snakes, hunting strategy is conserved phylogenetically; most species employ only one strategy. Active hunters encounter and capture more prey but invest more energy in hunting and have higher risks of being predated. This trade-off is important to small predators. The small Cerastes vipera employs both modes of hunting, which is unlike most viperids which use only sit-and wait ambushing. This species hibernates in October and emerges in April. Energy intake should be high prior to hibernation to overcome the non-feeding hibernation period and for reproduction on their emergence. We predicted that more individuals would hunt actively towards hibernation and an abiotic factor would trigger this response. Furthermore, since more energy is required for active hunting, we predicted that snakes in good body condition would use active hunting to a greater extent than snakes in poor body condition. To test our predictions, we tracked free-living snakes year round and determined their hunting strategy, estimated their body condition index (BCI), and calculated circannual parameters of day length as environmental cues known to affect animal behaviour. Two novel findings emerged in this study, namely, hunting strategy was affected significantly by 1) the circannual change in day length and 2) by BCI. The proportion of active hunters increased from 5% in April to over 30% in October and BCI of active foragers was higher than that of sit-and-wait foragers and, therefore, our predictions were supported. The entrainment between the proportion of active hunting and the abiotic factor is indicative of an adaptive function for choosing a hunting strategy. A trend was evident among life stages. When all life stages were present (September-October), the proportion of active foragers increased with age: 0.0% among neonates, 18.2% among juveniles and 31.4% among adults. We concluded that vulnerable small neonates used sit-and-wait ambush not only as a hunting strategy but also as a hiding technique. Copyright © 2016 Elsevier B.V. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tom, Nathan; Lawson, Michael; Yu, Yi-Hsiang
The aim of this paper is to present a novel wave energy converter device concept that is being developed at the National Renewable Energy Laboratory. The proposed concept combines an oscillating surge wave energy converter with active control surfaces. These active control surfaces allow for the device geometry to be altered, which leads to changes in the hydrodynamic properties. The device geometry will be controlled on a sea state time scale and combined with wave-to-wave power-take-off control to maximize power capture, increase capacity factor, and reduce design loads. The paper begins with a traditional linear frequency domain analysis of themore » device performance. Performance sensitivity to foil pitch angle, the number of activated foils, and foil cross section geometry is presented to illustrate the current design decisions; however, it is understood from previous studies that modeling of current oscillating wave energy converter designs requires the consideration of nonlinear hydrodynamics and viscous drag forces. In response, a nonlinear model is presented that highlights the shortcomings of the linear frequency domain analysis and increases the precision in predicted performance.« less
Activity-related energy expenditure during lower limb cast immobilization in children.
Maggio, Albane B; Martin, Xavier E; Ceroni, Dimitri
2017-05-01
Physical inactivity, which may result from immobilization, is recognized as a risk factor for the development of obesity. We aimed to quantify the decrease in activity-related energy expenditure (AEE) because of lower limb cast immobilization. We carried out a longitudinal matched case-control study: 34 adolescents with a first episode of lower limb fracture and 34 healthy cases. Physical activity was assessed during cast immobilization by an accelerometer from which we calculated the decrease in AEE. AEE in adolescents with lower limb fractures was estimated to be 16.0% lower than healthy controls. When converted into kcal per mean participants' weight, the difference in AEE amounted to 125 kcal/day, which corresponds to 5.2 h of slow walking. A significant reduction of AEE in adolescents with lower limb fractures may lead to a significantly positive energy balance as there is usually no compensatory reduction of energy intake. An increase of walking seems unrealistic in this situation and patients should be advised at the emergency unit to reduce their energy intake during the immobilization period. Level III, prospective case-control study.
Mutoh, Shingo; Sobhany, Mack; Moore, Rick; Perera, Lalith; Pedersen, Lee; Sueyoshi, Tatsuya; Negishi, Masahiko
2017-01-01
Phenobarbital is a central nervous system depressant that also indirectly activates nuclear receptor constitutive active androstane receptor (CAR), which promotes drug and energy metabolism, as well as cell growth (and death), in the liver. We found that phenobarbital activated CAR by inhibiting epidermal growth factor receptor (EGFR) signaling. Phenobarbital bound to EGFR and potently inhibited the binding of EGF, which prevented the activation of EGFR. This abrogation of EGFR signaling induced the dephosphorylation of receptor for activated C kinase 1 (RACK1) at Tyr52, which then promoted the dephosphorylation of CAR at Thr38 by the catalytic core subunit of protein phosphatase 2A. The findings demonstrated that the phenobarbital-induced mechanism of CAR dephosphorylation and activation is mediated through its direct interaction with and inhibition of EGFR. PMID:23652203
Mutoh, Shingo; Sobhany, Mack; Moore, Rick; Perera, Lalith; Pedersen, Lee; Sueyoshi, Tatsuya; Negishi, Masahiko
2013-05-07
Phenobarbital is a central nervous system depressant that also indirectly activates nuclear receptor constitutive active androstane receptor (CAR), which promotes drug and energy metabolism, as well as cell growth (and death), in the liver. We found that phenobarbital activated CAR by inhibiting epidermal growth factor receptor (EGFR) signaling. Phenobarbital bound to EGFR and potently inhibited the binding of EGF, which prevented the activation of EGFR. This abrogation of EGFR signaling induced the dephosphorylation of receptor for activated C kinase 1 (RACK1) at Tyr(52), which then promoted the dephosphorylation of CAR at Thr(38) by the catalytic core subunit of protein phosphatase 2A. The findings demonstrated that the phenobarbital-induced mechanism of CAR dephosphorylation and activation is mediated through its direct interaction with and inhibition of EGFR.
Chriqui, Jamie F.; Burgeson, Charlene R.; Fisher, Megan C.; Ness, Roberta B.
2013-01-01
Childhood obesity is a serious public health problem, resulting from energy imbalance (when the intake of energy is greater than the amount of energy expended through physical activity). Numerous health authorities have identified policy interventions as promising strategies for creating population-wide improvements in physical activity. This case study focuses on energy expenditure through physical activity (with a particular emphasis on school-based physical education [PE]). Policy-relevant evidence for promoting physical activity in youth may take numerous forms including epidemiologic data and other supporting evidence (e.g., qualitative data). The implementation and evaluation of school PE interventions leads to a set of lessons related to epidemiology and evidence-based policy. These include the need to: 1) enhance the focus on external validity, 2) develop more policy-relevant evidence based on “natural experiments,” 3) understand that policymaking is political, 4) better articulate the factors that influence policy dissemination, 5) understand the real world constraints when implementing policy in school environments, and 6) build transdisciplinary teams for policy progress. The issues described in this case study provide leverage points for practitioners, policy makers, and researchers as they seek to translate epidemiology to policy. PMID:20470970
Effects of the Menopausal Transition on Factors Related to Energy Balance. A MONET group Study
Karine, Duval; Denis, Prud’homme; Rémi, Rabasa-Lhoret; Irene, Strychar; Martin, Brochu; Jean-Marc, Lavoie; Éric, Doucet
2016-01-01
Objectives Factors that influence weight gain during the menopausal transition are not fully understood. The purpose of this study was to investigate changes in energy expenditure (EE) across the menopausal transition. Methods One hundred and two premenopausal women (age: 49.9 ± 1.9 yrs; BMI: 23.3 ± 2.2 kg/m2) were followed for 5 years. Body composition (DXA), physical activity EE (accelerometer), resting EE and thermic effect of food (indirect calorimetry) were measured annually. Results Total EE decreased significantly over time in postmenopausal women (P < 0.05), which was mostly due to a decrease in physical activity EE (P < 0.05). Although average resting EE remained stable over time in postmenopausal women, a significant increase, over the 5-year period, was noted in women who were in the menopausal transition by year 5 (P < 0.05). Finally, the time spent in moderate physical activity decreased and the time spent in sedentary physical activity increased during the menopausal transition (P < 0.05). Conclusion These results suggest that menopausal transition is accompanied with a decline in EE mainly characterized by a decrease in physical activity EE and a shift to a more sedentary lifestyle. PMID:23422924
Zou, Minzhong; Niu, Jun; Kang, Shaozhong; Li, Xiaolin; Lu, Hongna
2017-08-18
Evapotranspiration (ET) is a major component linking the water, energy, and carbon cycles. Understanding changes in ET and the relative contribution rates of human activity and of climate change at the basin scale is important for sound water resources management. In this study, changes in ET in the Heihe agricultural region in northwest China during 1984-2014 were examined using remotely-sensed ET data with the Soil and Water Assessment Tool (SWAT). Correlation analysis identified the dominant factors that influence change in ET per unit area and those that influence change in total ET. Factor analysis identified the relative contribution rates of the dominant factors in each case. The results show that human activity, which includes factors for agronomy and irrigation, and climate change, including factors for precipitation and relative humidity, both contribute to increases in ET per unit area at rates of 60.93% and 28.01%, respectively. Human activity, including the same factors, and climate change, including factors for relative humidity and wind speed, contribute to increases in total ET at rates of 53.86% and 35.68%, respectively. Overall, in the Heihe agricultural region, the contribution of human agricultural activities to increased ET was significantly greater than that of climate change.
Mitre, Naim; Foster, Randal C; Lanningham-Foster, Lorraine; Levine, James A.
2014-01-01
Background Screen time continues to be a major contributing factor to sedentariness in children. There have been more creative approaches to increase physical over the last few years. One approach has been through the use of video games. In the present study we investigated the effect of television watching and the use of activity-promoting video games on energy expenditure and movement in lean and obese children. Our primary hypothesis was that energy expenditure and movement decreases while watching television, in lean and obese children. Our secondary hypothesis was that energy expenditure and movement increases when playing the same game with an activity-promoting video game console compared to a sedentary video game console, in lean and obese children. Methods Eleven boys (10 ± 1 year) and eight girls (9 ± 1 year) ranging in BMI from 14–29 kg/m2 (eleven lean and eight overweight or obese) were recruited. Energy expenditure and physical activity were measured while participants were watching television, playing a video game on a traditional sedentary video game console, and while playing the same video game on an activity-promoting video game (Nintendo Wii) console. Results Energy expenditure was significantly greater than television watching and playing video games on a sedentary video game console when children played the video game on the activity-promoting console(125.3 ± 38.2 Kcal/hr vs. 79.7 ± 20.1 and 79.4 ±15.7, P<0.0001, respectively). When examining movement with accelerometry, children moved significantly more when playing the video game on the Nintendo Wii console (p<0.0001). Conclusion The amount of movement and energy expenditure of television watching and playing video games on a sedentary video game console is not different. Activity-promoting video games have shown to increase movement, and be an important tool to raise energy expenditure by 50% when compared to sedentary activities of daily living. PMID:22145458
Reactivity of bromoalkanes in reactions of coordinated molecular decay
NASA Astrophysics Data System (ADS)
Pokidova, T. S.; Denisov, E. T.
2016-09-01
The results from experiments on reactions of the coordinated molecular decay of RBr bromoalkanes on olefin and HBr are analyzed using the model of intersecting parabolas (MIP). Kinetic parameters within the MIP are calculated from the experimental data, enabling calculation of the activation energies ( E) and rate constants ( k) of such reactions, based on the enthalphy of the reaction and the MIP algorithms. The factors affecting the E of the RBr decay reaction are established: the enthalphy of the reaction, triplet repulsion, the energy of radical R• stabilization, the presence of a π bond adjacent to the reaction center, and the dipole-dipole interaction of polar groups. The energy spectrum of the partial energies of activation is constructed for the reaction of coordinated molecular decay of RBr, and the E and k of inverse addition reactions are evaluated.
Goto, Tsuyoshi; Takahashi, Nobuyuki; Kawada, Teruo
2015-01-01
Obesity is a major risk factor for chronic diseases such as diabetes, cardiovascular diseases, and hypertension. Many modern people have a tendency to overeat owing to stress and loosening of self-control. Moreover, energy expenditure varies greatly among individuals. Scientific reduction of obesity is important under these circumstances. Furthermore, recent research on molecular levels has clarified the differentiation of adipocytes, the level of subsequent fat accumulation, and the secretion of the biologically active adipokines by adipocytes. Adipose tissues and obesity have become the most important target for the prevention and treatment of many chronic diseases. We have identified various food-derived compounds modulating nuclear receptors, especially peroxisome proliferators-activated receptor(PPAR), in the regulation of energy metabolism and obesity. In this review, we discuss the PPARs that are most important in obesity and energy metabolism.
Sun, Qiang
2017-10-01
With the concerns of ecological and circular economy along with sustainable development, reverse logistics has attracted the attention of enterprise. How to achieve sustainable development of reverse logistics has important practical significance of enhancing low carbon competitiveness. In this paper, the system boundary of reverse logistics carbon footprint is presented. Following the measurement of reverse logistics carbon footprint and reverse logistics carbon capacity is provided. The influencing factors of reverse logistics carbon footprint are classified into five parts such as intensity of reverse logistics, energy structure, energy efficiency, reverse logistics output, and product remanufacturing rate. The quantitative research methodology using ADF test, Johansen co-integration test, and impulse response is utilized to interpret the relationship between reverse logistics carbon footprint and the influencing factors more accurately. This research finds that energy efficiency, energy structure, and product remanufacturing rate are more capable of inhibiting reverse logistics carbon footprint. The statistical approaches will help practitioners in this field to structure their reverse logistics activities and also help academics in developing better decision models to reduce reverse logistics carbon footprint.
NASA Astrophysics Data System (ADS)
Jagdeo, J.; Ravikumar, A. P.; Grubert, E.; Brandt, A. R.
2016-12-01
Unconventional oil and natural gas production in the U.S. has increased tenfold between 2005 and 2014 due to advances in hydraulic fracturing technology. Prior studies of hydraulic fracturing activity have mainly focused on two themes: the environmental impacts related to air and water pollution or the direct and spillover economic benefits resulting from oil booms at the state and local level. However, the impacts of hydraulic fracturing extend beyond these effects. Oil-boom counties have experienced environmental changes in land-use and water supply and witnessed social changes in demographics, crime, and health, factors that are not typically evaluated in regard to hydraulic fracturing. Hence, there is a need to consider the holistic effects of oil production on communities. This study examines the environmental, economic, and social impacts of oil and gas activity in Williams County, North Dakota by comparing its pre-boom ( 2005) and post-boom ( 2014) conditions. Annual oil production in Williams County increased from 3.4 million barrels in 2005 to 56 million barrels in 2014, providing an ideal test-case to study the impact of energy development on surrounding communities. We compared changes in multiple impact categories, attributed directly or indirectly to hydraulic fracturing activity, to trends at the national level. For example, between 2005 and 2014, CO2 and CH4 emissions primarily from oil and gas activity increased by 360 thousand metric tons CO2e, corresponding to a 20-fold increase. Concurrently, national emissions decreased by 10.5%. Over twenty indicators were analyzed across environmental, social and economic impact categories, including land-use change, median household income, and crime rates. The datasets were normalized using federal regulations for upper and lower bounds, or calibrated against national averages. Normalized indicators are then aggregated to provide a single-value `impact-factor'. Such `impact-factor' maps will provide a unified and holistic assessment that can be used to readily compare the impact of energy development across American counties. This type of assessment can be used in corporate and political decision-making to examine the environmental, economic, and social impacts of energy-related activity.
Development of Scintillators in Nuclear Medicine.
Khoshakhlagh, Mohammad; Islamian, Jalil Pirayesh; Abedi, Seyed Mohammad; Mahmoudian, Babak
2015-01-01
High-quality image is necessary for accurate diagnosis in nuclear medicine. There are many factors in creating a good image and detector is the most important one. In recent years, several detectors are studied to get a better picture. The aim of this paper is comparison of some type of these detectors such as thallium activated sodium iodide bismuth germinate cesium activated yttrium aluminum garnet (YAG: Ce) YAP: Ce "lutetium aluminum garnet activated by cerium" CRY018 "CRY019" lanthanum bromide and cadmium zinc telluride. We studied different properties of these crystals including density, energy resolution and decay times that are more important factors affecting the image quality.
Development of Scintillators in Nuclear Medicine
Khoshakhlagh, Mohammad; Islamian, Jalil Pirayesh; Abedi, Seyed Mohammad; Mahmoudian, Babak
2015-01-01
High-quality image is necessary for accurate diagnosis in nuclear medicine. There are many factors in creating a good image and detector is the most important one. In recent years, several detectors are studied to get a better picture. The aim of this paper is comparison of some type of these detectors such as thallium activated sodium iodide bismuth germinate cesium activated yttrium aluminum garnet (YAG: Ce) YAP: Ce “lutetium aluminum garnet activated by cerium” CRY018 “CRY019” lanthanum bromide and cadmium zinc telluride. We studied different properties of these crystals including density, energy resolution and decay times that are more important factors affecting the image quality. PMID:26420984
The boron implantation in the varied zone MBE MCT epilayer
NASA Astrophysics Data System (ADS)
Voitsekhovskii, Alexander V.; Grigor'ev, Denis V.; Kokhanenko, Andrey P.; Korotaev, Alexander G.; Sidorov, Yuriy G.; Varavin, Vasiliy S.; Dvoretsky, Sergey A.; Mikhailov, Nicolay N.; Talipov, Niyaz Kh.
2005-09-01
In the paper experimental results on boron implantation of the CdxHg1-xTe epilayers with various composition near surface of the material are discussed. The electron concentration in the surface layer after irradiation vs irradiation dose and ion energy are investigated for range of doses 1011 - 3•1015 cm-2 and energies of 20 - 150 keV. Also the results of the electrical active defects distribution measurement, carried out by differential Hall method, after boron implantation are represented. Consideration of the received data shows, that composition gradient influence mainly on the various dynamics of accumulation of electric active radiation defects. The electric active defects distribution analysis shows, that the other factors are negligible.
Peroxisome proliferator-activated receptor gamma signaling in human sperm physiology
Liu, Li-Li; Xian, Hua; Cao, Jing-Chen; Zhang, Chong; Zhang, Yong-Hui; Chen, Miao-Miao; Qian, Yi; Jiang, Ming
2015-01-01
Peroxisome proliferator-activated receptor gamma (PPARγ) is a member of the PPARs, which are transcription factors of the steroid receptor superfamily. PPARγ acts as an important molecule for regulating energy homeostasis, modulates the hypothalamic-pituitary-gonadal (HPG) axis, and is reciprocally regulated by HPG. In the human, PPARγ protein is highly expressed in ejaculated spermatozoa, implying a possible role of PPARγ signaling in regulating sperm energy dissipation. PPARγ protein is also expressed in Sertoli cells and germ cells (spermatocytes). Its activation can be induced during capacitation and the acrosome reaction. This mini-review will focus on how PPARγ signaling may affect fertility and sperm quality and the potential reversibility of these adverse effects. PMID:25851655
Dietary factors in relation to daily activity energy expenditure and mortality among older adults
Shahar, Danit R.; Harris, Tamara B.; Houston, Denise K.; Kritchevsky, Stephen B.; Lee, Jung-Sun; Rubin, Susan M.; Sellmeyer, Deborah E.; Tylavsky, Frances A.; Yu, Binbing
2009-01-01
Objective To examine the association between dietary factors to daily activity energy expenditure (DAEE) and mortality among older adults. Design and setting A sub-study of Health, Aging, and Body Composition study. Participants 298 older participants (aged 70–82 years) in the Health, Aging, and Body Composition Energy Expenditure sub-study. Measurements Dietary factors, DAEE, and all-cause mortality were measured in 298 older participants. Dietary factors include dietary intake assessed by the Block Food Frequency Questionnaire (FFQ), Healthy Eating Index (HEI), and self-reported appetite and enjoyment of eating. DAEE was assessed using doubly labeled water. All-cause mortality was evaluated over a 9 year period. Results Participants in the highest tertile of DAEE were more likely to be men and to report having a ‘good’ appetite; BMI among men, proportion married, IL-6 and CRP levels and energy intake were also higher. Fewer black participants were in the ‘good’ HEI category. Participants in the ‘good’ HEI category had higher cognitive scores and a higher education level. Participants who reported improvement in their appetite as well as participants who reported a ‘good’ appetite were at lower risk for mortality (HR (95% CI): 0.42 (0.24–0.74) and 0.50 (0.26–0.88), respectively) even after adjusting for DAEE, demographic, nutritional and health indices. Conclusions We showed an association between DAEE and appetite and mortality among well-functioning, community-dwelling older adults. These findings may have some practical use for the health providers. Inclusion of a question regarding appetite of an elderly patient may provide important information regarding risk for health deterioration and mortality. PMID:19390747
Energy as a Constraint on Habitability in the Subsurface
NASA Astrophysics Data System (ADS)
Hoehler, T.
2008-12-01
All living things must obtain energy from the environment to grow, to maintain a metabolic steady state, or simply to preserve viability. The availability of energy sources in the environment thus represents a key factor in determining the size, distribution, and activity of biological populations, and ultimately constrains the possibility for life itself. Lacking the abundant energy provided by solar radiation or the products of oxygenic photosynthesis, life in subsurface environments may be limited by energy availability as much as any other factor. The biological requirement for energy is expressed in two dimensions - analogous to the power and voltage requirements of electrical devices - and consideration and quantification of these requirements establishes quantitative boundary conditions on subsurface habitability. The magnitude of these requirements depends significantly on physicochemical environment, as does the provision of biologically-accessible energy from subsurface sources. With this conceptual basis, we are developing an 'energy balance' model that is designed to ultimately predict the habitability of a given environment, with respect to a given metabolism, in quantitative terms (as 'biomass density potential'). The model will develop from conceptual to quantitative as experimental and observational work constrains and quantifies, in natural populations adapted to low energy conditions, the magnitude of the biological energy requirements and the impacts of physicochemical environmental conditions on energy demand and supply.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Evans, Meredydd
2000-12-31
Energy service companies have played a significant role in stimulating energy efficiency in many industrialized countries, including the United States. Many policymakers and development experts consider energy performance contracting an important mechanism for boosting energy efficiency in other countries as well. The experience of ESCOs in transition economies, however, is decidedly mixed. The Czech Republic has been able to foster a thriving ESCO industry with numerous players competing for business, although ESCOs have encountered problems along the way. In Russia and Ukraine, ESCOs have developed slowly, and few true performance contracts exist. This paper reviews the experience of ESCOs inmore » the Czech Republic, Ukraine and Russia and then explores the factors shaping the diverse trends in these countries. The paper draws on the experience of the national energy efficiency centers, development banks, bilateral assistance organizations and individual ESCOs in promoting ESCO industries. Factors that have influenced ESCOs to date include the economy, the price of energy, the financial situation of potential clients, the legislative basis for ESCO activities, the business experience of ESCO staff and access to information about the ESCO concept. Financing has also proven to be a critical factor in developing ESCOs. Lack of project financing and guarantees, for example, is a major problem in the former Soviet Union. The paper concludes by drawing recommendations for policymakers and industry on promoting ESCOs.« less
Diffusion and aggregation of subsurface radiation defects in lithium fluoride nanocrystals
NASA Astrophysics Data System (ADS)
Voitovich, A. P.; Kalinov, V. S.; Martynovich, E. F.; Stupak, A. P.; Runets, L. P.
2015-09-01
Lithium fluoride nanocrystals were irradiated by gamma rays at a temperature below the temperature corresponding to the mobility of anion vacancies. The kinetics of the aggregation of radiation-induced defects in subsurface layers of nanocrystals during annealing after irradiation was elucidated. The processes that could be used to determine the activation energy of the diffusion of anion vacancies were revealed. The value of this energy in subsurface layers was obtained. For subsurface layers, the concentrations ratio of vacancies and defects consisting of one vacancy and two electrons was found. The factors responsible for the differences in the values of the activation energies and concentration ratios in subsurface layers and in the bulk of the crystals were discussed.
Bazzini, G; Capodaglio, E; Panigazzi, M; Prestifilippo, E; Vercesi, C
2010-01-01
For posture we mean the position of the body in the space and the relationship with its segments. The correct posture is determined by neurophysiological, biomechanical, emotional, psychological and relation factors, enabling us to perform daily and working activities with the lowest energy expenditure. When possible we suggest during posture variation, a preventive measure where there are prolonged fixed activities.
[Systemic and local mechanisms leading to cachexia in cancer].
Grabiec, Kamil; Burchert, Marta; Milewska, Marta; Błaszczyk, Maciej; Grzelkowska-Kowalczyk, Katarzyna
2013-12-31
Cachexia is a multifactorial syndrome of atrophy of skeletal muscle and adipose tissue, resulting in progressive loss of body weight associated with low quality of life and poor prognosis in cancer. Studies on experimental animal models and observations on patients have shown that the soluble factors secreted by tumor cells and tissues of the patient can participate in regulation of the wasting process. Cachexia is often accompanied by anorexia, which is caused by predominance of signals inhibiting appetite in the hypothalamus, such as release of proopiomelanocortin and anorexigenic action of proinflammatory cytokines (IL-1α, IL-1β, IL-6, TNF-α). Cachexia is also accompanied by extensive metabolic changes consisting of increase of resting energy expenditure and disturbance of carbohydrate, protein and lipid metabolism. Increased expression of protein uncoupling phosphorylation leads to increased thermogenesis in skeletal muscle. Tumor tissue hypoxia caused by its growth beyond blood vessels activates the transcription factor HIF-1, which results in increase in glycolysis, and leads to lactic acid accumulation and activation of the energy inefficient Cori cycle. Loss of fat tissue is caused by increase of lipolysis induced by lipid-mobilizing factor (LMF) and proinflammatory cytokines. Skeletal muscle wasting in cachexia is caused by a reduction of protein synthesis at the stage of initiation and elongation of translation and the simultaneous increase of protein degradation via ubiquitin-dependent and lysosomal pathways. The main mediators of skeletal muscle wasting in cancer are proteolysis-inducing factor (PIF), proinflammatory cytokines, and angiotensin II acting through increased levels of reactive oxygen species (ROS) and nuclear factor NF-κB activation, as well as glucocorticoid activated FOXO transcription factors and myostatin. Understanding of the complexity of the interaction of factors produced by the tumor and the patient's body may form the basis for the development of effective treatments for cachexia in cancer and other pathological conditions.
Determination of oxygen diffusion kinetics during thin film ruthenium oxidation
DOE Office of Scientific and Technical Information (OSTI.GOV)
Coloma Ribera, R., E-mail: r.colomaribera@utwente.nl; Kruijs, R. W. E. van de; Yakshin, A. E.
2015-08-07
In situ X-ray reflectivity was used to reveal oxygen diffusion kinetics for thermal oxidation of polycrystalline ruthenium thin films and accurate determination of activation energies for this process. Diffusion rates in nanometer thin RuO{sub 2} films were found to show Arrhenius behaviour. However, a gradual decrease in diffusion rates was observed with oxide growth, with the activation energy increasing from about 2.1 to 2.4 eV. Further exploration of the Arrhenius pre-exponential factor for diffusion process revealed that oxidation of polycrystalline ruthenium joins the class of materials that obey the Meyer-Neldel rule.
Sergeeva, Tatiana F; Shirmanova, Marina V; Zlobovskaya, Olga A; Gavrina, Alena I; Dudenkova, Varvara V; Lukina, Maria M; Lukyanov, Konstantin A; Zagaynova, Elena V
2017-03-01
A complex cascade of molecular events occurs in apoptotic cells but cell-to-cell variability significantly complicates determination of the order and interconnections between different processes. For better understanding of the mechanisms of programmed cell death, dynamic simultaneous registration of several parameters is required. In this paper we used multiparameter fluorescence microscopy to analyze energy metabolism, intracellular pH and caspase-3 activation in living cancer cells in vitro during staurosporine-induced apoptosis. We performed metabolic imaging of two co-factors, NAD(P)H and FAD, and used the genetically encoded pH-indicator SypHer1 and the FRET-based sensor for caspase-3 activity, mKate2-DEVD-iRFP, to visualize these parameters by confocal fluorescence microscopy and two-photon fluorescence lifetime imaging microscopy. The correlation between energy metabolism, intracellular pH and caspase-3 activation and their dynamic changes were studied in CT26 cancer cells during apoptosis. Induction of apoptosis was accompanied by a switch to oxidative phosphorylation, cytosol acidification and caspase-3 activation. We showed that alterations in cytosolic pH and the activation of oxidative phosphorylation are relatively early events associated with the induction of apoptosis. Copyright © 2017 Elsevier B.V. All rights reserved.
[Chronic heart failure and cachexia: role of endocrine system].
Dei Cas, A; Muoio, A; Zavaroni, I
2011-12-01
Chronic heart failure (CHF) is a major health problem that carries a devastating prognosis. The prognosis worsens considerably once cardiac cachexia has been diagnosed. Neurohormonal, metabolic, hemodynamic and immunological alterations are involved in the initiation and progression of cardiac cachexia. Cachexia is characterized by a hypothalamic inappropriate response to the mechanisms controlling energy homeostasis. Levels of the anorexigenic hormone leptin are decreased whereas the orexigenic gherlin hormone levels are normal or elevated. Nevertheless, energy intake is not increased as expected due to a persistent activation of the proopiomelanocortin (POMC) system (anorexigenic) paralleled by a decreased activity of the neuropeptide Y (NPY, orexigenic) neurons. Cachexia is also characterized by an imbalance in anabolic (impairment in the growth hormone/insulin-like growth factor-I axis, insulin resistance) and catabolic (increased levels of catecholamines, increased cortisol/dehydroepiandrosterone ratio and activation of proinflammatory cytokines such as tumor necrosis factor-alpha, interleuchin-6, interleuchin-1') at the basis of the wasting process. This review discusses the complex role of the endocrine system in modulating energy balance, appetite and metabolism in patients with chronic heart failure. A joint multidisciplinary effort of the cardiologists, immunologists and endocrinologists might be useful to identify the precise mechanisms involved in the neuroendocrine alteration and to develop therapeutic strategies able to improve the prognosis of CHF patients.
The Role of Awards Programs in Stimulating Energy Efficient Behavior: A Study of Award Winners
DOE Office of Scientific and Technical Information (OSTI.GOV)
McDermott, Christa; Malone, Elizabeth L.
The value of formal awards programs may be principally in gaining wider recognition for achievements in energy efficiency. But how do these programs contribute to the goal that is presumably behind this value, i.e., stimulating further energy efficient behavior, beyond publicizing the awards ceremonies and describing the projects via websites, posters, and the like? Interviews with 22 individuals and teams of award winners under the Department of Energy Federal Energy Management Program (DOE FEMP) yield insights on the roles that awards programs can play in stimulating energy efficient behavior, especially with regard to institutional dimensions of such behavior. Award winnersmore » identified institutional facilitators and barriers in their projects and programs as well as factors in their implementation processes, thus providing information that can guide other efforts. Although only one of the interviewees affirmed that winning an award was a motivating factor, awards do validate often-hard-won achievements through recognition and, in some cases, additional resources, thus stimulating both the winners themselves and those who see the achievements to further energy-saving activities. Finally, award winners’ responses demonstrated the importance of behavioral and institutional change in energy efficiency.« less
Xu, Di; Chai, Meiyun; Dong, Zhujun; Rahman, Md Maksudur; Yu, Xi; Cai, Junmeng
2018-06-04
The kinetic compensation effect in the logistic distributed activation energy model (DAEM) for lignocellulosic biomass pyrolysis was investigated. The sum of square error (SSE) surface tool was used to analyze two theoretically simulated logistic DAEM processes for cellulose and xylan pyrolysis. The logistic DAEM coupled with the pattern search method for parameter estimation was used to analyze the experimental data of cellulose pyrolysis. The results showed that many parameter sets of the logistic DAEM could fit the data at different heating rates very well for both simulated and experimental processes, and a perfect linear relationship between the logarithm of the frequency factor and the mean value of the activation energy distribution was found. The parameters of the logistic DAEM can be estimated by coupling the optimization method and isoconversional kinetic methods. The results would be helpful for chemical kinetic analysis using DAEM. Copyright © 2018 Elsevier Ltd. All rights reserved.
Ernest Orlando Lawrence Berkeley National Laboratory institutional plan, FY 1996--2001
DOE Office of Scientific and Technical Information (OSTI.GOV)
NONE
1995-11-01
The FY 1996--2001 Institutional Plan provides an overview of the Ernest Orlando Lawrence Berkeley National Laboratory mission, strategic plan, core business areas, critical success factors, and the resource requirements to fulfill its mission in support of national needs in fundamental science and technology, energy resources, and environmental quality. The Laboratory Strategic Plan section identifies long-range conditions that will influence the Laboratory, as well as potential research trends and management implications. The Core Business Areas section identifies those initiatives that are potential new research programs representing major long-term opportunities for the Laboratory, and the resources required for their implementation. It alsomore » summarizes current programs and potential changes in research program activity, science and technology partnerships, and university and science education. The Critical Success Factors section reviews human resources; work force diversity; environment, safety, and health programs; management practices; site and facility needs; and communications and trust. The Resource Projections are estimates of required budgetary authority for the Laboratory`s ongoing research programs. The Institutional Plan is a management report for integration with the Department of Energy`s strategic planning activities, developed through an annual planning process. The plan identifies technical and administrative directions in the context of the national energy policy and research needs and the Department of Energy`s program planning initiatives. Preparation of the plan is coordinated by the Office of Planning and Communications from information contributed by the Laboratory`s scientific and support divisions.« less
Microglia activation due to obesity programs metabolic failure leading to type two diabetes.
Maldonado-Ruiz, R; Montalvo-Martínez, L; Fuentes-Mera, L; Camacho, A
2017-03-20
Obesity is an energy metabolism disorder that increases susceptibility to the development of metabolic diseases. Recently, it has been described that obese subjects have a phenotype of chronic inflammation in organs that are metabolically relevant for glucose homeostasis and energy. Altered expression of immune system molecules such as interleukins IL-1, IL-6, IL-18, tumor necrosis factor alpha (TNF-α), serum amyloid A (SAA), and plasminogen activator inhibitor-1 (PAI-1), among others, has been associated with the development of chronic inflammation in obesity. Chronic inflammation modulates the development of metabolic-related comorbidities like metabolic syndrome (insulin resistance, glucose tolerance, hypertension and hyperlipidemia). Recent evidence suggests that microglia activation in the central nervous system (CNS) is a priority in the deregulation of energy homeostasis and promotes increased glucose levels. This review will cover the most significant advances that explore the molecular signals during microglia activation and inflammatory stage in the brain in the context of obesity, and its influence on the development of metabolic syndrome and type two diabetes.
Takaoka, Saori; Kamioka, Yuji; Takakura, Kanako; Baba, Ai; Shime, Hiroaki; Seya, Tsukasa; Matsuda, Michiyuki
2016-05-01
Transforming growth factor-β activated kinase 1 (TAK1) has been shown to play a crucial role in cell death, differentiation, and inflammation. Here, we live-imaged robust TAK1 activation in Lewis lung carcinoma 3LL cells implanted into the s.c. tissue of syngeneic C57BL/6 mice and treated with polyinosinic:polycytidylic acid (PolyI:C). First, we developed and characterized a Förster resonance energy transfer-based biosensor for TAK1 activity. The TAK1 biosensor, named Eevee-TAK1, responded to stress-inducing reagents such as anisomycin, tumor necrosis factor-α, and interleukin1-β. The anisomycin-induced increase in Förster resonance energy transfer was abolished by the TAK1 inhibitor (5z)-7-oxozeaenol. Activity of TAK1 in 3LL cells was markedly increased by PolyI:C in the presence of macrophages. 3LL cells expressing Eevee-TAK1 were implanted into mice and observed through imaging window by two-photon excitation microscopy. During the growth of tumor, the 3LL cells at the periphery of the tumor showed higher TAK1 activity than the 3LL cells located at the center of the tumor, suggesting that cells at the periphery of the tumor mass were under stronger stress. Injection of PolyI:C, which is known to induce regression of the implanted tumors, induced marked and homogenous TAK1 activation within the tumor tissues. The effect of PolyI:C faded within 4 days. These observations suggest that Eevee-TAK1 is a versatile tool to monitor cellular stress in cancer tissues. © 2016 The Authors. Cancer Science published by John Wiley & Sons Australia, Ltd on behalf of Japanese Cancer Association.
Seong, Jihye; Ouyang, Mingxing; Kim, Taejin; Sun, Jie; Wen, Po-Chao; Lu, Shaoying; Zhuo, Yue; Llewellyn, Nicholas M; Schlaepfer, David D; Guan, Jun-Lin; Chien, Shu; Wang, Yingxiao
2011-07-26
Proper subcellular localization of focal adhesion kinase (FAK) is crucial for many cellular processes. It remains, however, unclear how FAK activity is regulated at subcellular compartments. To visualize the FAK activity at different membrane microdomains, we develop a fluorescence resonance energy transfer (FRET)-based FAK biosensor, and target it into or outside of detergent-resistant membrane (DRM) regions at the plasma membrane. Here we show that, on cell adhesion to extracellular matrix proteins or stimulation by platelet-derived growth factor (PDGF), the FRET responses of DRM-targeting FAK biosensor are stronger than that at non-DRM regions, suggesting that FAK activation can occur at DRM microdomains. Further experiments reveal that the PDGF-induced FAK activation is mediated and maintained by Src activity, whereas FAK activation on cell adhesion is independent of, and in fact essential for the Src activation. Therefore, FAK is activated at membrane microdomains with distinct activation mechanisms in response to different physiological stimuli. © 2011 Macmillan Publishers Limited. All rights reserved.
Low-Force Muscle Activity Regulates Energy Expenditure after Spinal Cord Injury.
Woelfel, Jessica R; Kimball, Amy L; Yen, Chu-Ling; Shields, Richard K
2017-05-01
Reduced physical activity is a primary risk factor for increased morbidity and mortality. People with spinal cord injury (SCI) have reduced activity for a lifetime, as they cannot volitionally activate affected skeletal muscles. We explored whether low-force and low-frequency stimulation is a viable strategy to enhance systemic energy expenditure in people with SCI. This study aimed to determine the effects of low stimulation frequency (1 and 3 Hz) and stimulation intensity (50 and 100 mA) on energy expenditure in people with SCI. We also examined the relationship between body mass index and visceral adipose tissue on energy expenditure during low-frequency stimulation. Ten individuals with complete SCI underwent oxygen consumption monitoring during electrical activation of the quadriceps and hamstrings at 1 and 3 Hz and at 50 and 100 mA. We calculated the difference in energy expenditure between stimulation and rest and estimated the number of days that would be necessary to burn 1 lb of body fat (3500 kcal) for each stimulation protocol (1 vs 3 Hz). Both training frequencies induced a significant increase in oxygen consumption above a resting baseline level (P < 0.05). Energy expenditure positively correlated with stimulus intensity (muscle recruitment) and negatively correlated with adiposity (reflecting the insulating properties of adipose tissue). We estimated that 1 lb of body fat could be burned more quickly with 1 Hz training (58 d) as compared with 3 Hz training (87 d) if an identical number of pulses were delivered. Low-frequency stimulation increased energy expenditure per pulse and may be a feasible option to subsidize physical activity to improve metabolic status after SCI.
The tumor secretory factor ZAG promotes white adipose tissue browning and energy wasting.
Elattar, Sawsan; Dimri, Manali; Satyanarayana, Ande
2018-03-23
Cachexia is a complex tissue-wasting syndrome characterized by inflammation, hypermetabolism, increased energy expenditure, and anorexia. Browning of white adipose tissue (WAT) is one of the significant factors that contribute to energy wasting in cachexia. By utilizing a cell implantation model, we demonstrate here that the lipid mobilizing factor zinc-α 2 -glycoprotein (ZAG) induces WAT browning in mice. Increased circulating levels of ZAG not only induced lipolysis in adipose tissues but also caused robust browning in WAT. Stimulating WAT progenitors with ZAG recombinant protein or expression of ZAG in mouse embryonic fibroblasts (MEFs) strongly enhanced brown-like differentiation. At the molecular level, ZAG stimulated peroxisome proliferator-activated receptor γ (PPARγ) and early B cell factor 2 expression and promoted their recruitment to the PR/SET domain 16 (Prdm16) promoter, leading to enhanced expression of Prdm16, which determines brown cell fate. In brown adipose tissue, ZAG stimulated the expression of PPARγ and PPARγ coactivator 1α and promoted recruitment of PPARγ to the uncoupling protein 1 (Ucp1) promoter, leading to increased expression of Ucp1. Overall, our results reveal a novel function of ZAG in WAT browning and highlight the targeting of ZAG as a potential therapeutic application in humans with cachexia.-Elattar, S., Dimri, M., Satyanarayana, A. The tumor secretory factor ZAG promotes white adipose tissue browning and energy wasting.
Mukherjee, Sromona; Shukla, Charu; Britton, Steven L.; Koch, Lauren G.; Shi, Haifei; Novak, Colleen M.
2014-01-01
A high-calorie diet accompanied by low levels of physical activity (PA) accounts for the widespread prevalence of obesity today, and yet some people remain lean even in this obesogenic environment. Here, we investigate the cause for this exception. A key trait that predicts high PA in both humans and laboratory rodents is intrinsic aerobic capacity. Rats artificially selected as high-capacity runners (HCR) are lean and consistently more physically active than their low-capacity runner (LCR) counterparts; this applies to both males and females. Here, we demonstrate that HCR show heightened total energy expenditure (TEE) and hypothesize that this is due to higher nonresting energy expenditure (NREE; includes activity EE). After matching for body weight and lean mass, female HCR consistently had heightened nonresting EE, but not resting EE, compared with female LCR. Because of the dominant role of skeletal muscle in nonresting EE, we examined muscle energy use. We found that lean female HCR had higher muscle heat dissipation during activity, explaining their low economy of activity and high activity EE. This may be due to the amplified skeletal muscle expression levels of proteins involved in EE and reduced expression levels of proteins involved in energy conservation in HCR relative to LCR. This is also associated with an increased sympathetic drive to skeletal muscle in HCR compared with LCR. We find little support for the hypothesis that resting metabolic rate is correlated with maximal aerobic capacity if body size and composition are fully considered; rather, the critical factor appears to be activity thermogenesis. PMID:24398400
Mendenhall, C L; Moritz, T E; Roselle, G A; Morgan, T R; Nemchausky, B A; Tamburro, C H; Schiff, E R; McClain, C J; Marsano, L S; Allen, J I
1995-01-01
Active nutrition therapy and the anabolic steroid oxandrolone (OX), in selected patients with severe alcoholic hepatitis, significantly improved liver status and survival. We report here on the changes in their nutritional parameters. Protein energy malnutrition (PEM) was evaluated and expressed as percent of low normal in 271 patients initially, at 1 month and at 3 months. Active therapy consisted of OX plus a high caloric food supplement vs a matching placebo and a low calorie supplement. PEM was present in every patient; mean PEM score 60% of low normal. Most of the parameters improved significantly from baseline on standard care; the largest improvement seen in visceral proteins, the smallest in fat stores (skinfold thickness). Total PEM score significantly correlated with 6 month mortality (p = .0012). Using logistic regression analysis, creatinine height index, hand grip strength and total peripheral blood lymphocytes were the best risk factors for survival. When CD lymphocyte subsets replaced total lymphocyte counts in the equation, CD8 levels became a significant risk factor (p = .004). Active treatment produced significant risk factor (p = .004). Active treatment produced significant improvements in those parameters related to total body and muscle mass (ie, mid arm muscle area, p = .02; creatinine height index, p = .03; percent ideal body weight, p = .04). Deterioration in nutritional parameters is a significant risk factor for survival in severe patients with alcoholic hepatitis. This deterioration is reversible with standard hospital care. Active therapy further improves creatinine height index, mid arm muscle area and total lymphocyte counts. Hence, these later parameters appear to be the best indicators for follow-up assessments.
NASA Astrophysics Data System (ADS)
Ekasiwi, S. N. N.; Antaryama, I. G. N.; Krisdianto, J.; Ulum, M. S.
2018-03-01
Classrooms in educational buildings require certain lighting requirements to serve teaching and learning activities during daytime. The most typical design is double sided opening in order to get good daylight distribution in the classroom. Using artificial light is essential to contribute the worse daylight condition. A short observation indicates that during the lecture time the light turned on, even in the daytime. That might result in wasting electrical energy. The aim of the study is to examine the type of classroom, which perform comfortable lighting environment as well as saving energy. This paper reports preliminary results of the study obtained from field observation and measurements. The use of energy and usage pattern of artificial lighting during the lecture is recorded and then the data evaluated to see the suitability of existing energy use to building energy standards. The daylighting design aspects have to be the first consideration. However, the similarity in WWR of the classroom, the Daylight Factor (DF) may differ. It depends on the room depth. The similarity of the increase of WWR and Ratio of openings to floor area do not directly correspond to the increase of DF. The outdoor condition of larger daylight access and the room depth are the influencing factors. Despite the similarity of physical type, usage pattern of the classroom imply the use of electrical energy for lighting. The results indicate the factors influencing lighting energy performance in correlation to their typologies
Estimating Physical Activity Energy Expenditure with the Kinect Sensor in an Exergaming Environment
Nathan, David; Huynh, Du Q.; Rubenson, Jonas; Rosenberg, Michael
2015-01-01
Active video games that require physical exertion during game play have been shown to confer health benefits. Typically, energy expended during game play is measured using devices attached to players, such as accelerometers, or portable gas analyzers. Since 2010, active video gaming technology incorporates marker-less motion capture devices to simulate human movement into game play. Using the Kinect Sensor and Microsoft SDK this research aimed to estimate the mechanical work performed by the human body and estimate subsequent metabolic energy using predictive algorithmic models. Nineteen University students participated in a repeated measures experiment performing four fundamental movements (arm swings, standing jumps, body-weight squats, and jumping jacks). Metabolic energy was captured using a Cortex Metamax 3B automated gas analysis system with mechanical movement captured by the combined motion data from two Kinect cameras. Estimations of the body segment properties, such as segment mass, length, centre of mass position, and radius of gyration, were calculated from the Zatsiorsky-Seluyanov's equations of de Leva, with adjustment made for posture cost. GPML toolbox implementation of the Gaussian Process Regression, a locally weighted k-Nearest Neighbour Regression, and a linear regression technique were evaluated for their performance on predicting the metabolic cost from new feature vectors. The experimental results show that Gaussian Process Regression outperformed the other two techniques by a small margin. This study demonstrated that physical activity energy expenditure during exercise, using the Kinect camera as a motion capture system, can be estimated from segmental mechanical work. Estimates for high-energy activities, such as standing jumps and jumping jacks, can be made accurately, but for low-energy activities, such as squatting, the posture of static poses should be considered as a contributing factor. When translated into the active video gaming environment, the results could be incorporated into game play to more accurately control the energy expenditure requirements. PMID:26000460
Eat less and exercise more - is it really enough to knock down the obesity pandemia?
Hubácek, J A
2009-01-01
Reduced physical activity and abundant energy intake are two most common factors leading to uncontrolled body weight gain. But these factors are not under entire internal consciousness control; they are also partially genetically determined and are affected by for example food marketing practices. In addition to these two widely accepted factors, there are some other factors, whose could also contribute to the recent increase of obesity prevalence. For example, non-exercise activity thermogenesis, sleeping habits, more stable inside room temperatures (using of heating and air conditioning), high prescription of medications with weight gain as side effect, psychosocial factors, unfavourable socioeconomic status and unpleasant urban environment are the background factors which should not be omitted if obesity/BMI determination should be fully understood and kept under control. In conclusion, unhealthy life style is necessary, but not sufficient for obesity development.
Disturbance of the reproductive axis induced by negative energy balance.
Judd, S J
1998-01-01
Animal reproduction is impaired when intake of energy is so restricted that activities essential to life are threatened; this is seen as a homeostatic adjustment that restricts wasteful energy expenditure. Fasting or exercising to a degree requiring considerable energy expenditure has major effects on the hypothalamus, including activation of corticotrophin-releasing factor (CRF) neurons, suppression of thyrotrophin-releasing hormone synthesis, and increased growth hormone secretion; these are associated with increased concentrations of hypothalamic neuropeptide Y mRNA and are corrected by administration of leptin, an adipose-tissue protein with a tertiary structure similar to the cytokine interleukin-2. This response to fasting results from a disordered pattern of activity in the gonadotrophin-releasing hormone (GnRH) pacemaker, characterized by reduced luteinizing hormone pulsatility, particularly during daytime. Animal studies have suggested that the response depends on an intact afferent vagal system from the stomach and the presence of oestrogen. Noradrenergic neurons forming the A2 group increase the activity of CRF neurons that, in turn, inhibit GnRH pulsatility. Reproductive impairment due to fasting is reversed by leptin, and abnormalities of leptin are described in individuals who fast or who develop exercise-induced amenorrhoea. This paper discusses these changes induced by negative energy balance and speculates on the involvement of leptin as a contributor to these abnormalities.
Nutrition and protein energy homeostasis in elderly.
Boirie, Yves; Morio, Béatrice; Caumon, Elodie; Cano, Noël J
2014-01-01
Protein-energy homeostasis is a major determinant of healthy aging. Inadequate nutritional intakes and physical activity, together with endocrine disturbances are associated with of sarcopenia and frailty. Guidelines from scientific societies mainly address the quantitative aspects of protein and energy nutrition in elderly. Besides these quantitative aspects of protein load, perspective strategies to promote muscle protein synthesis and prevent sarcopenia include pulse feeding, the use of fast proteins and the addition of leucine or citrulline to dietary protein. An integrated management of sarcopenia, taking into account the determinants of muscle wasting, i.e. nutrition, physical activity, anabolic factors such as androgens, vitamin D and n-3 polyunsaturated fatty acids status, needs to be tested in the prevention and treatment of sarcopenia. The importance of physical activity, specifically resistance training, is emphasized, not only in order to facilitate muscle protein anabolism but also to increase appetite and food intake in elderly people at risk of malnutrition. According to present data, healthy nutrition in elderly should respect the guidelines for protein and energy requirement, privilege a Mediterranean way of alimentation, and be associated with a regular physical activity. Further issues relate to the identification of the genetics determinants of protein energy wasting in elderly. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.
Furuhama, A; Aoki, Y; Shiraishi, H
2012-01-01
To understand the key factor for fish toxicity of 11 α,β-unsaturated carbonyl aldehydes and ketones, we used quantum chemical calculations to investigate their Michael reactions with methanethiol or glutathione. We used two reaction schemes, with and without an explicit water molecule (Scheme-1wat and Scheme-0wat, respectively), to account for the effects of a catalytic water molecule on the reaction pathway. We determined the energies of the reactants, transition states (TS), and products, as well as the activation energies of the reactions. The acute fish toxicities of nine of the carbonyl compounds were evaluated to correlate with their hydrophobicities; no correlation was observed for acrolein and crotonaldehyde. The most toxic compound, acrolein, had the lowest activation energy. The activation energy of the reaction could be estimated with Scheme-1wat but not with Scheme-0wat. The complexity of the reaction pathways of the compounds was reflected in the difficulty of the TS structure searches when Scheme-1wat was used with the polarizable continuum model. The theoretical estimations of activation energies of α,β-unsaturated carbonyl compounds with catalytic molecules or groups including hydrogen-bond networks may complement traditional tools for predicting the acute aquatic toxicities of compounds that cannot be easily obtained experimentally.
Ramdharry, Gita M; Pollard, Alexander J; Grant, Robert; Dewar, Elizabeth L; Laurá, Matilde; Moore, Sarah A; Hallsworth, Kate; Ploetz, Thomas; Trenell, Michael I; Reilly, Mary M
2017-08-01
Charcot Marie Tooth disease (CMT) describes a group of hereditary neuropathies that present with distal weakness, wasting and sensory loss. Small studies indicate that people with CMT have reduced daily activity levels. This raises concerns as physical inactivity increases the risk of a range of co- morbidities, an important consideration in the long-term management of this disease. This study aimed to compare physical activity, patterns of sedentary behavior and overall energy expenditure of people with CMT and healthy matched controls. We compared 20 people with CMT and 20 matched controls in a comparison of physical activity measurement over seven days, using an activity monitor. Patterns of sedentary behavior were explored through a power law analysis. Results showed a decrease in daily steps taken in the CMT group, but somewhat paradoxically, they demonstrate shorter bouts of sedentary activity and more frequent transitions from sedentary to active behaviors. No differences were seen in energy expenditure or time spent in sedentary, moderate or vigorous activity. The discrepancy between energy expenditure and number of steps could be due to higher energy requirements for walking, but also may be due to an over-estimation of energy expenditure by the activity monitor in the presence of muscle wasting. Alternatively, this finding may indicate that people with CMT engage more in activities or movement not related to walking. Implications for Rehabilitation Charcot-Marie-Tooth disease: • People with Charcot-Marie-Tooth disease did not show a difference in energy expenditure over seven days compared to healthy controls, but this may be due to higher energy costs of walking, and/or an over estimation of energy expenditure by the activity monitor in a population where there is muscle wasting. This needs to be considered when interpreting activity monitor data in people with neuromuscular diseases. • Compared to healthy controls, people with Charcot-Marie-Tooth disease had a lower step count over seven days, but exhibited more frequent transitions from sedentary to active behaviors • High Body Mass Index and increased time spent sedentary were related factors that have implications for general health status. • Understanding the profile of physical activity and behavior can allow targeting of rehabilitation interventions to address mobility and fitness.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Neff, Michael M.
This is a final report for Department of Energy Grant No. DE-FG02-08ER15927 entitled “Molecular Genetic Analysis of Activation-Tagged Transcription Factors Thought to be Involved in Photomorphogenesis”. Based on our preliminary photobiological and genetic analysis of the sob1-D mutant, we hypothesized that OBP3 is a transcription factor involved in both phytochrome and cryptochrome-mediated signal transduction. In addition, we hypothesized that OBP3 is involved in auxin signaling and root development. Based on our preliminary photobiological and genetic analysis of the sob2-D mutant, we also hypothesized that a related gene, LEP, is involved in hormone signaling and seedling development.
Potential active materials for photo-supercapacitor: A review
NASA Astrophysics Data System (ADS)
Ng, C. H.; Lim, H. N.; Hayase, S.; Harrison, I.; Pandikumar, A.; Huang, N. M.
2015-11-01
The need for an endless renewable energy supply, typically through the utilization of solar energy in most applications and systems, has driven the expansion, versatility, and diversification of marketed energy storage devices. Energy storage devices such as hybridized dye-sensitized solar cell (DSSC)-capacitors and DSSC-supercapacitors have been invented for energy reservation. The evolution and vast improvement of these devices in terms of their efficiencies and flexibilities have further sparked the invention of the photo-supercapacitor. The idea of coupling a DSSC and supercapacitor as a complete energy conversion and storage device arose because the solar energy absorbed by dye molecules can be efficiently transferred and converted to electrical energy by adopting a supercapacitor as the energy delivery system. The conversion efficiency of a photo-supercapacitor is mainly dependent on the use of active materials during its fabrication. The performances of the dye, photoactive metal oxide, counter electrode, redox electrolyte, and conducting polymer are the primary factors contributing to high-energy-efficient conversion, which enhances the performance and shelf-life of a photo-supercapacitor. Moreover, the introduction of compact layer as a primary adherent film has been earmarked as an effort in enhancing power conversion efficiency of solar cell. Additionally, the development of electrolyte-free solar cell such as the invention of hole-conductor or perovskite solar cell is currently being explored extensively. This paper reviews and analyzes the potential active materials for a photo-supercapacitor to enhance the conversion and storage efficiencies.
Atmospheric energy for subsurface life on Mars?
Weiss, Benjamin P.; Yung, Yuk L.; Nealson, Kenneth H.
2000-01-01
The location and density of biologically useful energy sources on Mars will limit the biomass, spatial distribution, and organism size of any biota. Subsurface Martian organisms could be supplied with a large energy flux from the oxidation of photochemically produced atmospheric H2 and CO diffusing into the regolith. However, surface abundance measurements of these gases demonstrate that no more than a few percent of this available flux is actually being consumed, suggesting that biological activity driven by atmospheric H2 and CO is limited in the top few hundred meters of the subsurface. This is significant because the available but unused energy is extremely large: for organisms at 30-m depth, it is 2,000 times previous estimates of hydrothermal and chemical weathering energy and far exceeds the energy derivable from other atmospheric gases. This also implies that the apparent scarcity of life on Mars is not attributable to lack of energy. Instead, the availability of liquid water may be a more important factor limiting biological activity because the photochemical energy flux can only penetrate to 100- to 1,000-m depth, where most H2O is probably frozen. Because both atmospheric and Viking lander soil data provide little evidence for biological activity, the detection of short-lived trace gases will probably be a better indicator of any extant Martian life. PMID:10660689
NASA Astrophysics Data System (ADS)
Mariappan, C. R.
2014-05-01
AC conductivity spectra of Li-analogues NASICON-type Li1.5Al0.5Ge1.5P3O12 (LAGP), Li-Al-Ti-P-O (LATP) glass-ceramics and garnet-type Li7La2Ta2O13 (LLTO) ceramic are analyzed by universal power law and Summerfield scaling approaches. The activation energies and pre-exponential factors of total and grain conductivities are following the Meyer-Neldel (M-N) rule for NASICON-type materials. However, the garnet-type LLTO material deviates from the M-N rule line of NASICON-type materials. The frequency- and temperature-dependent conductivity spectra of LAGP and LLTO are superimposed by Summerfield scaling. The scaled conductivity curves of LATP are not superimposed at the grain boundary response region. The superimposed conductivity curves are observed at cross-over frequencies of grain boundary response region for LATP by incorporating the exp ( {{{ - (EAt - EAg )} {{{ - (EAt - EAg )} {kT}}} ) factor along with Summerfield scaling factors on the frequency axis, where EAt and EAg are the activation energies of total and grain conductivities, respectively.
Teo, Z; Sng, M K; Chan, J S K; Lim, M M K; Li, Y; Li, L; Phua, T; Lee, J Y H; Tan, Z W; Zhu, P; Tan, N S
2017-11-16
Metastatic cancer cells acquire energy-intensive processes including increased invasiveness and chemoresistance. However, how the energy demand is met and the molecular drivers that coordinate an increase in cellular metabolic activity to drive epithelial-mesenchymal transition (EMT), the first step of metastasis, remain unclear. Using different in vitro and in vivo EMT models with clinical patient's samples, we showed that EMT is an energy-demanding process fueled by glucose metabolism-derived adenosine triphosphate (ATP). We identified angiopoietin-like 4 (ANGPTL4) as a key player that coordinates an increase in cellular energy flux crucial for EMT via an ANGPTL4/14-3-3γ signaling axis. This augmented cellular metabolic activity enhanced metastasis. ANGPTL4 knockdown suppresses an adenylate energy charge elevation, delaying EMT. Using an in vivo dual-inducible EMT model, we found that ANGPTL4 deficiency reduces cancer metastasis to the lung and liver. Unbiased kinase inhibitor screens and Ingenuity Pathway Analysis revealed that ANGPTL4 regulates the expression of 14-3-3γ adaptor protein via the phosphatidylinositol-3-kinase/AKT and mitogen-activated protein kinase signaling pathways that culminate to activation of transcription factors, CREB, cFOS and STAT3. Using a different mode of action, as compared with protein kinases, the ANGPTL4/14-3-3γ signaling axis consolidated cellular bioenergetics and stabilized critical EMT proteins to coordinate energy demand and enhanced EMT competency and metastasis, through interaction with specific phosphorylation signals on target proteins.
Electricity by intermittent sources: An analysis based on the German situation 2012
NASA Astrophysics Data System (ADS)
Wagner, Friedrich
2014-02-01
The 2012 data of the German load, the on- and offshore and the photo-voltaic energy production are used and scaled to the limit of supplying the annual demand (100% case). The reference mix of the renewable energy (RE) forms is selected such that the remaining back-up energy is minimised. For the 100% case, the RE power installation has to be about 3 times the present peak load. The back-up system can be reduced by 12% in this case. The surplus energy corresponds to 26% of the demand. The back-up system and more so the grid must be able to cope with large power excursions. All components of the electricity supply system operate at low capacity factors. Large-scale storage can hardly be motivated by the effort to further reduce CO2 emission. Demand-side management will intensify the present periods of high economic activities. Its rigorous implementation will expand the economic activities into the weekends. On the basis of a simple criterion, the increase of periods with negative electricity prices in Germany is assessed. It will be difficult with RE to meet the low CO2 emission factors which characterise those European Countries which produce electricity mostly by nuclear and hydro power.
Regulation of Energy Stores and Feeding by Neuronal and Peripheral CREB Activity in Drosophila
Iijima, Koichi; Zhao, LiJuan; Shenton, Christopher; Iijima-Ando, Kanae
2009-01-01
The cAMP-responsive transcription factor CREB functions in adipose tissue and liver to regulate glycogen and lipid metabolism in mammals. While Drosophila has a homolog of mammalian CREB, dCREB2, its role in energy metabolism is not fully understood. Using tissue-specific expression of a dominant-negative form of CREB (DN-CREB), we have examined the effect of blocking CREB activity in neurons and in the fat body, the primary energy storage depot with functions of adipose tissue and the liver in flies, on energy balance, stress resistance and feeding behavior. We found that disruption of CREB function in neurons reduced glycogen and lipid stores and increased sensitivity to starvation. Expression of DN-CREB in the fat body also reduced glycogen levels, while it did not affect starvation sensitivity, presumably due to increased lipid levels in these flies. Interestingly, blocking CREB activity in the fat body increased food intake. These flies did not show a significant change in overall body size, suggesting that disruption of CREB activity in the fat body caused an obese-like phenotype. Using a transgenic CRE-luciferase reporter, we further demonstrated that disruption of the adipokinetic hormone receptor, which is functionally related to mammalian glucagon and β-adrenergic signaling, in the fat body reduced CRE-mediated transcription in flies. This study demonstrates that CREB activity in either neuronal or peripheral tissues regulates energy balance in Drosophila, and that the key signaling pathway regulating CREB activity in peripheral tissue is evolutionarily conserved. PMID:20041126
Merlen, Grégory; Gentric, Géraldine; Celton-Morizur, Séverine; Foretz, Marc; Guidotti, Jacques-Emmanuel; Fauveau, Véronique; Leclerc, Jocelyne; Viollet, Benoit; Desdouets, Chantal
2014-01-01
AMP-activated protein kinase (AMPK) is an evolutionarily conserved sensor of cellular energy status that contributes to restoration of energy homeostasis by slowing down ATP-consuming pathways and activating ATP-producing pathways. Unexpectedly, in different systems, AMPK is also required for proper cell division. In the current study, we evaluated the potential effect of the AMPK catalytic subunit, AMPKα1, on hepatocyte proliferation. Hepatocyte proliferation was determined in AMPKα1 knockout and wild-type mice in vivo after two thirds partial hepatectomy, and in vitro in primary hepatocyte cultures. The activities of metabolic and cell cycle-related signaling pathways were measured. After partial hepatectomy, hepatocytes proliferated rapidly, correlating with increased AMPK phosphorylation. Deletion of AMPKα1 delayed liver regeneration by impacting on G1/S transition phase. The proliferative defect of AMPKα1-deficient hepatocytes was cell autonomous, and independent of energy balance. The priming phase, lipid droplet accumulation, protein anabolic responses and growth factor activation after partial hepatectomy occurred normally in the absence of AMPKα1 activity. By contrast, mRNA and protein expression of cyclin A2, a key driver of S phase progression, were compromised in the absence of AMPK activity. Importantly, AMPKα1 controlled cyclin A2 transcription mainly through the ATF/CREB element. Our study highlights a novel role for AMPKα1 as a positive regulator of hepatocyte division occurring independently of energy balance. Copyright © 2013 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.
Mindell, Jennifer S; Coombs, Ngaire; Stamatakis, Emmanuel
2014-05-01
Physical inactivity is an important risk factor for many chronic diseases and contributes to obesity and poor mental well-being. The present paper describes the main advantages and disadvantages, practical problems, suggested uses, and future developments regarding self-reported and objective data collection in the context of dietary surveys. In dietary surveys, physical activity is measured primarily to estimate energy expenditure. Energy expenditure surveillance is important for tracking changes over time, particularly given the debates over the role of the relative importance of energy intake and expenditure changes in the aetiology of obesity. It is also important to assess the extent of underreporting of dietary intake in these surveys. Physical activity data collected should include details on the frequency, duration and relative intensity of activity for each activity type that contributes considerably to overall activity and energy expenditure. Problems of validity and reliability, associated with inaccurate assessment, recall bias, and social desirability bias, are well-known; children under 10 years cannot report their activities accurately. However, despite such limitations, questionnaires are still the dominant method of physical activity assessment in dietary surveys due to their low cost and relatively low participant burden. Objective, time-stamped measures that monitor heart rate and/or movement can provide more comprehensive, quantitative assessment of physical activity but at greater cost and participant burden. Although overcoming many limitations of questionnaires, objective measures also have drawbacks, including technical, practical and interpretational issues.
Complementary Hypotheses on Contributors to the Obesity Epidemic.
Davis, Rachel A H; Plaisance, Eric P; Allison, David B
2018-01-01
Increased rates of obesity have occurred within virtually every race, age, sex, ethnicity, and economic group. Despite substantial punditry on the issue, the exact reasons are incompletely known. The two most common factors cited as contributing to the obesity epidemic, and those whose causal influence on increasing obesity levels in the population are often presumed unequivocally, are food marketing practices and institutionally driven reductions in physical activity. These have been called "the big two." This Perspective builds on previous writings in this area to introduce additional factors that may contribute to the obesity epidemic. It is emphasized that there may be other factors working in combination with the big two, influencing body fatness through effects on energy intake, energy expenditure, and/or nutrient partitioning. © 2017 The Obesity Society.
Kopp-Woodroffe, S A; Manore, M M; Dueck, C A; Skinner, J S; Matt, K S
1999-03-01
Chronic energy deficit is one of the strongest factors contributors to exercise-induced menstrual dysfunction. In such cases, macro- and micronutrient intakes may also be low. This study presents the results of a diet and exercise training intervention program. designed to reverse athletic amenorrhea, on improving energy balance and nutritional status in 4 amenorrheic athletes. The 20-week program provided a daily sport nutrition supplement and 1 day of rest/week. The program increased protein intakes for the 3 athletes with a protein deficit to within the recommended levels for active individuals. Micronutrient intakes increased, as did serum concentrations of vitamin B12, folate, zinc, iron, and ferritin. These results indicate that some amenorrheic athletes have poor nutritional status due to restricted EIs and poor food selections. A sport nutrition supplement may improve energy balance and nutritional status in active amenorrheic women.
Mechanical work makes important contributions to surface chemistry at steps.
Francis, M F; Curtin, W A
2015-02-13
The effect of mechanical strain on the binding energy of adsorbates to late transition metals is believed to be entirely controlled by electronic factors, with tensile stress inducing stronger binding. Here we show, via computation, that mechanical strain of late transition metals can modify binding at stepped surfaces opposite to well-established trends on flat surfaces. The mechanism driving the trend is mechanical, arising from the relaxation of stored mechanical energy. The mechanical energy change can be larger than, and of opposite sign than, the energy changes due to electronic effects and leads to a violation of trends predicted by the widely accepted electronic 'd-band' model. This trend has a direct impact on catalytic activity, which is demonstrated here for methanation, where biaxial tension is predicted to shift the activity of nickel significantly, reaching the peak of the volcano plot and comparable to cobalt and ruthenium.
Non-homeostatic body weight regulation through a brainstem-restricted receptor for GDF15
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hsu, Jer-Yuan; Crawley, Suzanne; Chen, Michael
Under homeostatic conditions, animals use well-defined hypothalamic neural circuits to help maintain stable body weight, by integrating metabolic and hormonal signals from the periphery to balance food consumption and energy expenditure1,2. In stressed or disease conditions, however, animals use alternative neuronal pathways to adapt to the metabolic challenges of altered energy demand3. Recent studies have identified brain areas outside the hypothalamus that are activated under these ‘non-homeostatic’ conditions4,5,6, but the molecular nature of the peripheral signals and brain-localized receptors that activate these circuits remains elusive. Here we identify glial cell-derived neurotrophic factor (GDNF) receptor alpha-like (GFRAL) as a brainstem-restricted receptormore » for growth and differentiation factor 15 (GDF15). GDF15 regulates food intake, energy expenditure and body weight in response to metabolic and toxin-induced stresses; we show that Gfral knockout mice are hyperphagic under stressed conditions and are resistant to chemotherapy-induced anorexia and body weight loss. GDF15 activates GFRAL-expressing neurons localized exclusively in the area postrema and nucleus tractus solitarius of the mouse brainstem. It then triggers the activation of neurons localized within the parabrachial nucleus and central amygdala, which constitute part of the ‘emergency circuit’ that shapes feeding responses to stressful conditions7. GDF15 levels increase in response to tissue stress and injury, and elevated levels are associated with body weight loss in numerous chronic human diseases8,9. By isolating GFRAL as the receptor for GDF15-induced anorexia and weight loss, we identify a mechanistic basis for the non-homeostatic regulation of neural circuitry by a peripheral signal associated with tissue damage and stress. These findings provide opportunities to develop therapeutic agents for the treatment of disorders with altered energy demand.« less
Carnoske, Cheryl; Hoehner, Christine; Ruthmann, Nicholas; Frank, Lawrence; Handy, Susan; Hill, James; Ryan, Sherry; Sallis, James; Glanz, Karen; Brownson, Ross
2010-03-01
Although public support for physical activity-friendly Traditional Neighborhood Developments (TNDs) appears to be growing, information is lacking on private sector perspectives and how economic factors (eg, fuel prices) might influence the development and sale of TNDs. A sample of realtors from the National Association of Realtors (n = 4950) and developers from the National Association of Home Builders (n = 162) were surveyed in early 2009 to assess factors influencing homebuyers' decisions; incentives and barriers to developing TNDs; effects of depressed housing market conditions and financing on sales; trends in buying; and energy considerations (eg, green building). Realtors believed that homebuyers continue to rank affordability, safety and school quality higher than TND amenities. Developers reported numerous barriers to TNDs, including the inability to overcome governmental/political hurdles, lack of cooperation between government agencies, and lack of market demand. Yet, realtors believed clients are increasingly influenced by gas and oil prices, and developers reported that clients are looking for energy efficient homes, reduced commute time, and walkable neighborhoods. Respondents reported consumers are more interested in living in a TND than 5 years ago. Activity-friendly TNDs appear to be increasing in demand, but developers and realtors reported significant barriers to creating these communities.
Carnoske, Cheryl; Hoehner, Christine; Ruthmann, Nicholas; Frank, Lawrence; Handy, Susan; Hill, James; Ryan, Sherry; Sallis, James; Glanz, Karen; Brownson, Ross
2013-01-01
Background Although public support for physical activity-friendly Traditional Neighborhood Developments (TNDs) appears to be growing, information is lacking on private sector perspectives and how economic factors (eg, fuel prices) might influence the development and sale of TNDs. Methods A sample of realtors from the National Association of Realtors (n = 4950) and developers from the National Association of Home Builders (n = 162) were surveyed in early 2009 to assess factors influencing homebuyers’ decisions; incentives and barriers to developing TNDs; effects of depressed housing market conditions and financing on sales; trends in buying; and energy considerations (eg, green building). Results Realtors believed that homebuyers continue to rank affordability, safety and school quality higher than TND amenities. Developers reported numerous barriers to TNDs, including the inability to overcome governmental/political hurdles, lack of cooperation between government agencies, and lack of market demand. Yet, realtors believed clients are increasingly influenced by gas and oil prices, and developers reported that clients are looking for energy efficient homes, reduced commute time, and walkable neighborhoods. Respondents reported consumers are more interested in living in a TND than 5 years ago. Conclusions Activity-friendly TNDs appear to be increasing in demand, but developers and realtors reported significant barriers to creating these communities. PMID:20440012
An Energetic Concept of Habitability for the Deep Subsurface
NASA Technical Reports Server (NTRS)
Hoehler, Tori M.
2006-01-01
Universally, life must be characterized by a characteristic level of order and complexity. In the most general sense, habitability could then be defined as the set of factors required to allow the creation and maintenance of molecular complexity. These factors are: chemical raw materials; energy with which to assemble those materials into complex molecules and sustain the resultant state of complexity; a solvent that allows the interaction of complex molecules, promotes tertiary structure, and permits compartmentalization; and environmental conditions that permit the assembly and maintenance of complex molecules. On Earth, these general requirements correspond to the major biogenic elements C, H, O, N, P, S; chemical or light energy; the solvent water; and specific ranges of temperature, pH, radiation, ionic strength, and so forth, which have thus far been determined on and exclusively empirical basis. Importantly, while the complete absence of any of these factors ensures uninhabitable conditions, the mere presence of all four does not guarantee habitability. In each case - even that of water - it is a question of degree. This question can be couched in quantitative terms by considering the impact of each of these factors on cellular energy balance. More "extreme" conditions (e.g., high temperature, high or low pH, etc.), lower water activity, and low concentrations of nutrients incur or have potential to be addressed by increased investment of energy on the part of the cell. This must be balanced by energy conservation in the cell, noting that biochemical, mass transport, and abiotic chemical limitations intervene between environmental energy availability and biological energy capture. Similarly, lower boundary conditions are emplaced on useful environmental energy yields by the "quantized" nature of biological energy conservation, and upper boundary conditions are emplaced by energy levels or fluxes that are destructive with respect to complexity. This energetic framework, with boundary conditions supplied by the specifics of the biochemistry in question, offers a generalized, yet quantitative means of assessing the habitability of any system with respect to complex life.
Boudaba, Nadia; Marion, Allison; Huet, Camille; Pierre, Rémi; Viollet, Benoit; Foretz, Marc
2018-02-01
Nonalcoholic fatty liver disease is a highly prevalent component of disorders associated with disrupted energy homeostasis. Although dysregulation of the energy sensor AMP-activated protein kinase (AMPK) is viewed as a pathogenic factor in the development of fatty liver its role has not been directly demonstrated. Unexpectedly, we show here that liver-specific AMPK KO mice display normal hepatic lipid homeostasis and are not prone to fatty liver development, indicating that the decreases in AMPK activity associated with hepatic steatosis may be a consequence, rather than a cause, of changes in hepatic metabolism. In contrast, we found that pharmacological re-activation of downregulated AMPK in fatty liver is sufficient to normalize hepatic lipid content. Mechanistically, AMPK activation reduces hepatic triglyceride content both by inhibiting lipid synthesis and by stimulating fatty acid oxidation in an LKB1-dependent manner, through a transcription-independent mechanism. Furthermore, the effect of the antidiabetic drug metformin on lipogenesis inhibition and fatty acid oxidation stimulation was enhanced by combination treatment with small-molecule AMPK activators in primary hepatocytes from mice and humans. Overall, these results demonstrate that AMPK downregulation is not a triggering factor in fatty liver development but in contrast, establish the therapeutic impact of pharmacological AMPK re-activation in the treatment of fatty liver disease. Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.
Arend, Matthias G; Franke, Thomas
2017-03-01
The objective of the present research was to understand drivers' interaction patterns with hybrid electric vehicles' (HEV) eco-features (electric propulsion, regenerative braking, neutral mode) and their relationship to fuel efficiency and driver characteristics (technical system knowledge, eco-driving motivation). Eco-driving (driving behaviors performed to achieve higher fuel efficiency) has the potential to reduce CO 2 emissions caused by road vehicles. Eco-driving in HEVs is particularly challenging due to the systems' dynamic energy flows. As a result, drivers are likely to show diverse eco-driving behaviors, depending on factors like knowledge and motivation. The eco-features represent an interface for the control of the systems' energy flows. A sample of 121 HEV drivers who had constantly logged their fuel consumption prior to the study participated in an online questionnaire. Drivers' interaction patterns with the eco-features were related to fuel efficiency. A common factor was identified in an exploratory factor analysis, characterizing the intensity of actively dealing with electric energy, which was also related to fuel efficiency. Driver characteristics were not related to this factor, yet they were significant predictors of fuel efficiency. From the perspective of user-energy interaction, the relationship of the aggregated factor to fuel efficiency emphasizes the central role of drivers' perception of and interaction with energy conversions in determining HEV eco-driving success. To arrive at an in-depth understanding of drivers' eco-driving behaviors that can guide interface design, authors of future research should be concerned with the psychological processes that underlie drivers' interaction patterns with eco-features.
Activation measurement of the 3He(alpha,gamma)7Be cross section at low energy.
Bemmerer, D; Confortola, F; Costantini, H; Formicola, A; Gyürky, Gy; Bonetti, R; Broggini, C; Corvisiero, P; Elekes, Z; Fülöp, Zs; Gervino, G; Guglielmetti, A; Gustavino, C; Imbriani, G; Junker, M; Laubenstein, M; Lemut, A; Limata, B; Lozza, V; Marta, M; Menegazzo, R; Prati, P; Roca, V; Rolfs, C; Alvarez, C Rossi; Somorjai, E; Straniero, O; Strieder, F; Terrasi, F; Trautvetter, H P
2006-09-22
The nuclear physics input from the 3He(alpha,gamma)7Be cross section is a major uncertainty in the fluxes of 7Be and 8B neutrinos from the Sun predicted by solar models and in the 7Li abundance obtained in big-bang nucleosynthesis calculations. The present work reports on a new precision experiment using the activation technique at energies directly relevant to big-bang nucleosynthesis. Previously such low energies had been reached experimentally only by the prompt-gamma technique and with inferior precision. Using a windowless gas target, high beam intensity, and low background gamma-counting facilities, the 3He(alpha,gamma)7Be cross section has been determined at 127, 148, and 169 keV center-of-mass energy with a total uncertainty of 4%. The sources of systematic uncertainty are discussed in detail. The present data can be used in big-bang nucleosynthesis calculations and to constrain the extrapolation of the 3He(alpha,gamma)7Be astrophysical S factor to solar energies.
Crystal Nucleation Using Surface-Energy-Modified Glass Substrates.
Nordquist, Kyle A; Schaab, Kevin M; Sha, Jierui; Bond, Andrew H
2017-08-02
Systematic surface energy modifications to glass substrates can induce nucleation and improve crystallization outcomes for small molecule active pharmaceutical ingredients (APIs) and proteins. A comparatively broad probe for function is presented in which various APIs, proteins, organic solvents, aqueous media, surface energy motifs, crystallization methods, form factors, and flat and convex surface energy modifications were examined. Replicate studies ( n ≥ 6) have demonstrated an average reduction in crystallization onset times of 52(4)% (alternatively 52 ± 4%) for acetylsalicylic acid from 91% isopropyl alcohol using two very different techniques: bulk cooling to 0 °C using flat surface energy modifications or microdomain cooling to 4 °C from the interior of a glass capillary having convex surface energy modifications that were immersed in the solution. For thaumatin and bovine pancreatic trypsin, a 32(2)% reduction in crystallization onset times was demonstrated in vapor diffusion experiments ( n ≥ 15). Nucleation site arrays have been engineered onto form factors frequently used in crystallization screening, including microscope slides, vials, and 96- and 384-well high-throughput screening plates. Nucleation using surface energy modifications on the vessels that contain the solutes to be crystallized adds a layer of useful variables to crystallization studies without requiring significant changes to workflows or instrumentation.
THE COVERING FACTOR OF WARM DUST IN WEAK EMISSION-LINE ACTIVE GALACTIC NUCLEI
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhang, Xudong; Liu, Yuan, E-mail: zhangxd@ihep.ac.cn, E-mail: liuyuan@ihep.ac.cn
2016-10-20
Weak emission-line active galactic nuclei (WLAGNs) are radio-quiet active galactic nuclei (AGNs) that have nearly featureless optical spectra. We investigate the ultraviolet to mid-infrared spectral energy distributions of 73 WLAGNs (0.4 < z < 3) and find that most of them are similar to normal AGNs. We also calculate the covering factor of warm dust of these 73 WLAGNs. No significant difference is indicated by a KS test between the covering factor of WLAGNs and normal AGNs in the common range of bolometric luminosity. The implication for several models of WLAGNs is discussed. The super-Eddington accretion is unlikely to bemore » the dominant reason for the featureless spectrum of a WLAGN. The present results are still consistent with the evolution scenario, i.e., WLAGNs are in a special stage of AGNs.« less
Brownson, Ross C; Chriqui, Jamie F; Burgeson, Charlene R; Fisher, Megan C; Ness, Roberta B
2010-06-01
Childhood obesity is a serious public health problem resulting from energy imbalance (when the intake of energy is greater than the amount of energy expended through physical activity). Numerous health authorities have identified policy interventions as promising strategies for creating population-wide improvements in physical activity. This case study focuses on energy expenditure through physical activity (with a particular emphasis on school-based physical education [PE]). Policy-relevant evidence for promoting physical activity in youth may take numerous forms, including epidemiologic data and other supporting evidence (e.g., qualitative data). The implementation and evaluation of school PE interventions leads to a set of lessons related to epidemiology and evidence-based policy. These include the need to: (i) enhance the focus on external validity, (ii) develop more policy-relevant evidence on the basis of "natural experiments," (iii) understand that policy making is political, (iv) better articulate the factors that influence policy dissemination, (v) understand the real-world constraints when implementing policy in school environments, and (vi) build transdisciplinary teams for policy progress. The issues described in this case study provide leverage points for practitioners, policy makers, and researchers as they seek to translate epidemiology to policy. Copyright 2010 Elsevier Inc. All rights reserved.
Wang, Ping; Lu, Zhengnan; Sun, Jihong
2018-02-08
Background : New energy has become a key trend for global energy industry development. Talent plays a very critical role in the enhancement of new energy enterprise competitiveness. As a key component of talent, managers have been attracting more and more attention. The increase in job performance relies on, to a certain extent, incentive mechanism. Based on the Two-factor Theory, differences in influences and effects of different incentives on management performance have been checked in this paper from an empirical perspective. Methods : This paper selects the middle and low level managers in new energy enterprises as research samples and classifies the managers' performance into task performance, contextual performance and innovation performance. It uses manager performance questionnaires and intrinsic-extrinsic incentive factor questionnaires to investigate and study the effects and then uses Amos software to analyze the inner link between the intrinsic-extrinsic incentives and job performance. Results : Extrinsic incentives affect task performance and innovation performance positively. Intrinsic incentives impose active significant effects on task performance, contextual performance, and innovation performance. The intrinsic incentive plays a more important role than the extrinsic incentive. Conclusions : Both the intrinsic-extrinsic incentives affect manager performance positively and the intrinsic incentive plays a more important role than the extrinsic incentive. Several suggestions to management should be given based on these results.
Jockusch, Rebecca A.; Schnier, Paul D.; Price, William D.; Strittmatter, Eric. F.; Demirev, Plamen A.; Williams*, Evan R.
2005-01-01
Blackbody infrared radiative dissociation spectra of the (M + 5H)5+ through (M + 11H)11+ ions of the protein ubiquitin (8.6 kDa) formed by electrospray ionization were measured in a Fourier-transform mass spectrometer. The 5+ ion dissociates exclusively by loss of water and/or ammonia, whereas the 11+ charge state dissociates only by formation of complementary y and b ions. These two processes are competitive for intermediate charge state ions, with the formation of y and b ions increasingly favored for the higher charge states. The y and b ions are formed by cleavage of the backbone amide bond on the C-terminal side of acidic residues exclusively, with cleavage adjacent to aspartic acid favored. Thermal unimolecular dissociation rate constants for the dissociation of each of these charge states were measured. From the temperature dependence of these rates, Arrhenius activation parameters in the rapid energy exchange limit are obtained. The activation energies (Ea) and preexponential factors (A) for the 5+, 8+, and 9+ ions are 1.2 eV and 1012 s−1, respectively. These values for the 6+ and 7+ ions are 0.9–1.0 eV and 109 s−1, and those for the 10+ and 11+ ions are 1.6 eV and 1016–1017 s−1. Thus, with the exception of the 5+ ion, the higher charge states of ubiquitin have larger dissociation activation energies than the lower charge states. The different A factors observed for production of y and b ions from different precursor charge states indicate that they are formed by different mechanisms, ranging from relatively complex rearrangements to direct bond cleavages. These results clearly demonstrate that the relative dissociation rates of large biomolecule ions by themselves are not necessarily a reliable indicator of their relative dissociation energies, even when similar fragment ions are formed. PMID:9075403
Jockusch, R A; Schnier, P D; Price, W D; Strittmatter, E F; Demirev, P A; Williams, E R
1997-03-15
Blackbody infrared radiative dissociation spectra of the (M + 5H)5+ through (M + 11H)11+ ions of the protein ubiquitin (8.6 kDa) formed by electrospray ionization were measured in a Fourier-transform mass spectrometer. The 5+ ion dissociates exclusively by loss of water and/or ammonia, whereas the 11+ charge state dissociates only by formation of complementary y and b ions. These two processes are competitive for intermediate charge state ions, with the formation of y and b ions increasingly favored for the higher charge states. The y and b ions are formed by cleavage of the backbone amide bond on the C-terminal side of acidic residues exclusively, with cleavage adjacent to aspartic acid favored. Thermal unimolecular dissociation rate constants for the dissociation of each of these charge states were measured. From the temperature dependence of these rates, Arrhenius activation parameters in the rapid energy exchange limit are obtained. The activation energies (Ea) and preexponential factors (A) for the 5+, 8+, and 9+ ions are 1.2 eV and 10(12) s-1, respectively. These values for the 6+ and 7+ ions are 0.9-1.0 eV and 10(9) s-1, and those for the 10+ and 11+ ions are 1.6 eV and 10(16)-10(17) s-1. Thus, with the exception of the 5+ ion, the higher charge states of ubiquitin have larger dissociation activation energies than the lower charge states. The different A factors observed for production of y and b ions from different precursor charge states indicate that they are formed by different mechanisms, ranging from relatively complex rearrangements to direct bond cleavages. These results clearly demonstrate that the relative dissociation rates of large biomolecule ions by themselves are not necessarily a reliable indicator of their relative dissociation energies, even when similar fragment ions are formed.
Surveying predictors of late-life longitudinal change in daily activity energy expenditure.
Valiani, Vincenzo; Sourdet, Sandrine; Schoeller, Dale A; Mackey, Dawn C; Bauer, Douglas C; Glynn, Nancy W; Yamada, Yosuke; Harris, Tamara B; Manini, Todd M
2017-01-01
Total daily energy expenditure (TEE) is composed of resting metabolic rate (RMR), post-prandial thermogenesis and activity energy expenditure (AEE). Higher AEE is strongly associated with lower mortality and physical limitations among older adults, but factors that predict changes in AEE in septu and octogenarians are not clearly understood. To identify factors associated with late-life longitudinal change in AEE. Energy expenditure was re-assessed in 83 participants (average age at baseline, 74.4±3.2 years)-an average of 7.5±0.54 years since the baseline measure. RMR was measured using indirect calorimetry and the thermic effect of meals was estimated at 10% of TEE. AEE was calculated as: TEE(0.9)-RMR. Participants were categorized into two groups according to the estimated day-to-day precision of the doubly-labeled water technique. Those who were within 10% or increased relative to their initial AEE measurement were categorized as having preserved AEE. Participants who declined greater than 10% of their initial measurement were categorized as having reduced AEE. A variety of socio-demographic, functional and mental factors, body composition, community and personal behaviors, blood measurements and health conditions were evaluated between groups at baseline and changes during follow-up. Daily AEE declined 106.61±293.25 kcal, which equated to a 14.63±40.57 kcal/d decrease per year. Fifty-nine percent (n = 49) preserved their AEE and 41% (n = 34) declined. Those who demonstrated a decline in AEE were older, had lower walking speed at baseline and showed a higher lean mass loss during follow up. Otherwise, groups were similar for socio-demographic characteristics, body composition, mental and physical function, health conditions and community and personal behaviors at baseline and change in these factors during follow-up. This study demonstrates that AEE declines through the 8th decade of life and is associated with age, lower walking speed at baseline and lean mass loss. Additionally, there are a significant number of individuals who appear to be resilient to these declines despite having health events that are expected to have a negative impact on their physical activity.
Spatio-temporal distribution of energy radiation from low frequency tremor
NASA Astrophysics Data System (ADS)
Maeda, T.; Obara, K.
2007-12-01
Recent fine-scale hypocenter locations of low frequency tremors (LFTs) estimated by cross-correlation technique (Shelly et al. 2006; Maeda et al. 2006) and new finding of very low frequency earthquake (Ito et al. 2007) suggest that these slow events occur at the plate boundary associated with slow slip events (Obara and Hirose, 2006). However, the number of tremor detected by above technique is limited since continuous tremor waveforms are too complicated. Although an envelope correlation method (ECM) (Obara, 2002) enables us to locate epicenters of LFT without arrival time picks, however, ECM fails to locate LFTs precisely especially on the most active stage of tremor activity because of the low-correlation of envelope amplitude. To reveal total energy release of LFT, here we propose a new method for estimating the location of LFTs together with radiated energy from the tremor source by using envelope amplitude. The tremor amplitude observed at NIED Hi-net stations in western Shikoku simply decays in proportion to the reciprocal of the source-receiver distance after the correction of site- amplification factor even though the phases of the tremor are very complicated. So, we model the observed mean square envelope amplitude by time-dependent energy radiation with geometrical spreading factor. In the model, we do not have origin time of the tremor since we assume that the source of the tremor continuously radiates the energy. Travel-time differences between stations estimated by the ECM technique also incorporated in our locating algorithm together with the amplitude information. Three-component 1-hour Hi-net velocity continuous waveforms with a pass-band of 2-10 Hz are used for the inversion after the correction of site amplification factors at each station estimated by coda normalization method (Takahashi et al. 2005) applied to normal earthquakes in the region. The source location and energy are estimated by applying least square inversion to the 1-min window iteratively. As a first application of our method, we estimated the spatio-temporal distribution of energy radiation for 2006 May episodic tremor and slip event occurred in western Shikoku, Japan, region. Tremor location and their radiated energy are estimated for every 1 minute. We counted the number of located LFTs and summed up their total energy at each grid having 0.05-degree spacing at each day to figure out the spatio-temporal distribution of energy release of tremors. The resultant spatial distribution of radiated energy is concentrated at a specific region. Additionally, we see the daily change of released energy, both of location and amount, which corresponds to the migration of tremor activity. The spatio-temporal distribution of energy radiation of tremors is in good agreement with a spatio-temporal slip distribution of slow slip event estimated from Hi-net tiltmeter record (Hirose et al. 2007). This suggests that small continuous tremors occur associated with a rupture process of slow slip.
Amaral, Maria E; Barbuio, Raquel; Milanski, Marciane; Romanatto, Talita; Barbosa, Helena C; Nadruz, Wilson; Bertolo, Manoel B; Boschero, Antonio C; Saad, Mario J A; Franchini, Kleber G; Velloso, Licio A
2006-07-01
Tumor necrosis factor-alpha (TNF-alpha) is known to participate in the wastage syndrome that accompanies cancer and severe infectious diseases. More recently, a role for TNF-alpha in the pathogenesis of type 2 diabetes mellitus and obesity has been shown. Much of the regulatory action exerted by TNF-alpha upon the control of energy stores depends on its action on the hypothalamus. In this study, we show that TNF-alpha activates canonical pro-inflammatory signal transduction pathways in the hypothalamus of rats. These signaling events lead to the transcriptional activation of an early responsive gene and to the induction of expression of cytokines and a cytokine responsive protein such as interleukin-1beta, interleukin-6, interleukin-10 and suppressor of cytokine signalling-3, respectively. In addition, TNF-alpha induces the expression of neurotransmitters involved in the control of feeding and thermogenesis. Thus, TNF-alpha may act directly in the hypothalamus inducing a pro-inflammatory response and the modulation of expression of neurotransmitters involved in energy homeostasis.
Fabrication Processes to Generate Concentration Gradients in Polymer Solar Cell Active Layers
Inaba, Shusei; Vohra, Varun
2017-01-01
Polymer solar cells (PSCs) are considered as one of the most promising low-cost alternatives for renewable energy production with devices now reaching power conversion efficiencies (PCEs) above the milestone value of 10%. These enhanced performances were achieved by developing new electron-donor (ED) and electron-acceptor (EA) materials as well as finding the adequate morphologies in either bulk heterojunction or sequentially deposited active layers. In particular, producing adequate vertical concentration gradients with higher concentrations of ED and EA close to the anode and cathode, respectively, results in an improved charge collection and consequently higher photovoltaic parameters such as the fill factor. In this review, we relate processes to generate active layers with ED–EA vertical concentration gradients. After summarizing the formation of such concentration gradients in single layer active layers through processes such as annealing or additives, we will verify that sequential deposition of multilayered active layers can be an efficient approach to remarkably increase the fill factor and PCE of PSCs. In fact, applying this challenging approach to fabricate inverted architecture PSCs has the potential to generate low-cost, high efficiency and stable devices, which may revolutionize worldwide energy demand and/or help develop next generation devices such as semi-transparent photovoltaic windows. PMID:28772878
Fabrication Processes to Generate Concentration Gradients in Polymer Solar Cell Active Layers.
Inaba, Shusei; Vohra, Varun
2017-05-09
Polymer solar cells (PSCs) are considered as one of the most promising low-cost alternatives for renewable energy production with devices now reaching power conversion efficiencies (PCEs) above the milestone value of 10%. These enhanced performances were achieved by developing new electron-donor (ED) and electron-acceptor (EA) materials as well as finding the adequate morphologies in either bulk heterojunction or sequentially deposited active layers. In particular, producing adequate vertical concentration gradients with higher concentrations of ED and EA close to the anode and cathode, respectively, results in an improved charge collection and consequently higher photovoltaic parameters such as the fill factor. In this review, we relate processes to generate active layers with ED-EA vertical concentration gradients. After summarizing the formation of such concentration gradients in single layer active layers through processes such as annealing or additives, we will verify that sequential deposition of multilayered active layers can be an efficient approach to remarkably increase the fill factor and PCE of PSCs. In fact, applying this challenging approach to fabricate inverted architecture PSCs has the potential to generate low-cost, high efficiency and stable devices, which may revolutionize worldwide energy demand and/or help develop next generation devices such as semi-transparent photovoltaic windows.
NASA Astrophysics Data System (ADS)
Michelini, Elisa; Mirasoli, Mara; Karp, Matti; Virta, Marko; Roda, Aldo
2004-06-01
Estrogen receptor (ER) is a ligand-activated transcriptional factor, able to dimerize after activation and to bind specific DNA sequences (estrogen response elements), thus activating gene target transcription. Since ER homo- and hetero-dimerization (giving a-a and a-b isoforms) is a fundamental step for receptor activation, we developed an assay for detecting compounds that induce human ERa homo-dimerization based on bioluminescence resonance energy transfer (BRET). BRET is a non-radiative energy transfer, occurring between a luminescent donor and a fluorescent acceptor, that strictly depends on the closeness between the two proteins and can therefore be used for studying protein-protein interactions. We cloned ERa coding sequence in frame with either a variant of the green fluorescent protein (enhanced yellow fluorescent protein, EYFP) or Renilla luciferase (RLuc). Upon ERa homo-dimerization, BRET process takes place in the presence of the RLuc substrate coelenterazine resulting in EYFP emission at its characteristic wavelength. The ER alpha-Rluc and ER alpha-EYFP fusion proteins were cloned, then the occurrence of BRET in the presence of ER alpha activators was assayed both in vivo, within cells, and in vitro, with purified fusion proteins.
Effects of oncogenic mutations on the conformational free-energy landscape of EGFR kinase
Sutto, Ludovico; Gervasio, Francesco Luigi
2013-01-01
Activating mutations in the epidermal growth factor receptor (EGFR) tyrosine kinase are frequently found in many cancers. It has been suggested that changes in the equilibrium between its active and inactive conformations are linked to its oncogenic potential. Here, we quantify the effects of some of the most common single (L858R and T790M) and double (T790M-L858R) oncogenic mutations on the conformational free-energy landscape of the EGFR kinase domain by using massive molecular dynamics simulations together with parallel tempering, metadynamics, and one of the best force-fields available. Whereas the wild-type EGFR catalytic domain monomer is mostly found in an inactive conformation, our results show a clear shift toward the active conformation for all of the mutants. The L858R mutation stabilizes the active conformation at the expense of the inactive conformation and rigidifies the αC-helix. The T790M gatekeeper mutant favors activation by stabilizing a hydrophobic cluster. Finally, T790M with L858R shows a significant positive epistasis effect. This combination not only stabilizes the active conformation, but in nontrivial ways changes the free-energy landscape lowering the transition barriers. PMID:23754386
Effects of oncogenic mutations on the conformational free-energy landscape of EGFR kinase.
Sutto, Ludovico; Gervasio, Francesco Luigi
2013-06-25
Activating mutations in the epidermal growth factor receptor (EGFR) tyrosine kinase are frequently found in many cancers. It has been suggested that changes in the equilibrium between its active and inactive conformations are linked to its oncogenic potential. Here, we quantify the effects of some of the most common single (L858R and T790M) and double (T790M-L858R) oncogenic mutations on the conformational free-energy landscape of the EGFR kinase domain by using massive molecular dynamics simulations together with parallel tempering, metadynamics, and one of the best force-fields available. Whereas the wild-type EGFR catalytic domain monomer is mostly found in an inactive conformation, our results show a clear shift toward the active conformation for all of the mutants. The L858R mutation stabilizes the active conformation at the expense of the inactive conformation and rigidifies the αC-helix. The T790M gatekeeper mutant favors activation by stabilizing a hydrophobic cluster. Finally, T790M with L858R shows a significant positive epistasis effect. This combination not only stabilizes the active conformation, but in nontrivial ways changes the free-energy landscape lowering the transition barriers.
Kim, Kang Ho; Moore, David D
2017-01-01
The liver undergoes major changes in substrate utilization and metabolic output over the daily feeding and fasting cycle. These changes occur acutely in response to hormones such as insulin and glucagon, with rapid changes in signaling pathways mediated by protein phosphorylation and other post-translational modifications. They are also reflected in chronic alterations in gene expression in response to nutrient-sensitive transcription factors. Among these, the nuclear receptors farnesoid X receptor (FXR) and peroxisome proliferator activated receptor α (PPARα) provide an intriguing, coordinated response to maintain energy balance in the liver. FXR is activated in the fed state by bile acids returning to the liver, while PPARα is activated in the fasted state in response to the free fatty acids produced by adipocyte lipolysis or possibly other signals. Key Messages: Previous studies indicate that FXR and PPARα have opposing effects on each other's primary targets in key metabolic pathways including gluconeogenesis. Our more recent work shows that these 2 nuclear receptors coordinately regulate autophagy: FXR suppresses this pathway of nutrient and energy recovery, while PPARα activates it. Another recent study indicates that FXR activates the complement and coagulation pathway, while earlier studies identify this as a negative target of PPARα. Since secretion is a very energy- and nutrient-intensive process for hepatocytes, it is possible that FXR licenses it in the nutrient-rich fed state, while PPARα represses it to spare resources in the fasted state. Energy balance is a potential connection linking FXR and PPARα regulation of autophagy and secretion, 2 seemingly unrelated aspects of hepatocyte function. FXR and PPARα act coordinately to promote energy balance and homeostasis in the liver by regulating autophagy and potentially protein secretion. It is quite likely that their impact extends to additional pathways relevant to hepatic energy balance, and that these pathways will in turn interface with other well-known nutrient-responsive mechanisms of energy control. © 2017 S. Karger AG, Basel.
Reactivity of fluoroalkanes in reactions of coordinated molecular decomposition
NASA Astrophysics Data System (ADS)
Pokidova, T. S.; Denisov, E. T.
2017-08-01
Experimental results on the coordinated molecular decomposition of RF fluoroalkanes to olefin and HF are analyzed using the model of intersecting parabolas (IPM). The kinetic parameters are calculated to allow estimates of the activation energy ( E) and rate constant ( k) of these reactions, based on enthalpy and IPM algorithms. Parameters E and k are found for the first time for eight RF decomposition reactions. The factors that affect activation energy E of RF decomposition (the enthalpy of the reaction, the electronegativity of the atoms of reaction centers, and the dipole-dipole interaction of polar groups) are determined. The values of E and k for reverse reactions of addition are estimated.
NASA Astrophysics Data System (ADS)
Zheng, Chaocheng
2017-10-01
With the global environmental problems and energy crisis continuously emerging, all countries are taking active measures to achieve the benign development of domestic economy and society. Vehicle, as a large oil consumption and emissions of carbon dioxide, nend to be a revolutionary change. Therefore, the development of new energy electric vehicle has become the consensus of the world. On this background, this paper has sorted out the current state and the related development planning of new energy electric vehicles in different countries to predict the car ownership of the new energy electric vehicles using elastic coefficient method and setting different path of development, conclude that under the consideration of energy conservation and emissions reduction factors, our country should mainly promote the BEV to realize the maximum energy conservation and emissions reduction.
Energy monitoring based on human activity in the workplace
NASA Astrophysics Data System (ADS)
Mustafa, N. H.; Husain, M. N.; Abd Aziz, M. Z. A.; Othman, M. A.; Malek, F.
2014-04-01
Human behavior is the most important factor in order to manage energy usage. Nowadays, smart house technology offers a better quality of life by introducing automated appliance control and assistive services. However, human behaviors will contribute to the efficiency of the system. This paper will focus on monitoring efficiency based on duration time in office hours around 8am until 5pm which depend on human behavior atb the workplace. Then, the correlation coefficient method is used to show the relation between energy consumption and energy saving based on the total hours of time energy spent. In future, the percentages of energy monitoring system usage will be increase to manage energy in efficient ways based on human behaviours. This scenario will lead to the positive impact in order to achieve the energy saving in the building and support the green environment.
Activation Volume for Hf Diffusion in an Amorphous Ni{sub 0.54}Zr{sub 0.46} Alloy
DOE Office of Scientific and Technical Information (OSTI.GOV)
Grandjean, A.; Limoge, Y.; Blanchard, P.
In this Letter we present the results of a diffusion study of Hf in a Ni{sub 0.54}Zr{sub 0.46} amorphous alloy. We have measured the diffusion properties with and without pressure, up to 1GPa. From these measurements we can deduce an Arrhenius behavior of the diffusion, with an activation energy of 0.76eV and a pre-exponential factor of 7.4{times}10{sup -17}m{sup 2}/s. The activation volume amounts to 8.5{angstrom};{sup 3}. Activation volume and energy are related by the Keyes relationship. We then discuss to what extent presently proposed diffusion mechanisms, point defects, or collective processes can be tested against these results. {copyright} {ital 1997}more » {ital The American Physical Society}« less
Li, Xian Liang; Man, Kwan; Ng, Kevin T; Lee, Terence K; Lo, Chung Mau; Fan, Sheung Tat
2004-09-01
Ischemia / reperfusion (I / R) injury is related to tissue graft energy status. Insulin, which is currently used in the University of Wisconsin (UW) preservation solution with insulin (UWI), is an anabolic hormone and was shown to exacerbate the hepatic I / R injury in our previous study. In this study, the energy status and regulation of metabolism genes by insulin were investigated in liver grafts preserved by UW solution. Insulin could significantly decrease adenosine triphosphate (ATP) level after 3 hours of preservation, as well as total adenine nucleotides (TANs) and energy charge (EC) levels. Energy regeneration deteriorated in the grafts preserved by insulin in terms of ATP and EC levels at 24 hours after transplantation. The insulin signal was transduced through the insulin receptor substrate-2 (IRS-2) pathway and the activity of IRS-2 was decreased gradually at the messenger ribonucleic acid (mRNA) level during cold preservation. Downstream targeting genes such as sterol regulatory element-binding protein-1c (SREBP-1c), glucokinase (GKC), and fatty acid synthase (FAS) genes, as well as phospho-glycogen synthase kinase-3beta (GSK-3beta) were activated and they showed the similar expression profiles during cold preservation. Lipoprotein metabolism was accelerated by insulin through upregulation of the activity of apolipoprotein C-III (Apo C-III) during cold preservation. The insulin-like growth factor-binding protein-1 pathway was inhibited during cold preservation. In conclusion, insulin in UW solution exacerbates hepatic I / R injury by energy depletion as the graft maintains its anabolic activity. The key enzyme activities of the energy-consuming process of glycogen and fatty acid synthesis as well as lipoprotein metabolism were accelerated by insulin through the IRS-2 / SREBP-1c pathway.
Shook, Robin P; Hand, Gregory A; Drenowatz, Clemens; Hebert, James R; Paluch, Amanda E; Blundell, John E; Hill, James O; Katzmarzyk, Peter T; Church, Timothy S; Blair, Steven N
2015-12-01
Previous studies suggest that appetite may be dysregulated at low levels of activity, creating an energy imbalance that results in weight gain. The aim was to examine the relation between energy intake, physical activity, appetite, and weight gain during a 1-y follow-up period in a large sample of adults. Participants included 421 individuals (mean ± SD age: 27.6 ± 3.8 y). Measurements included the following: energy intake with the use of interviewer-administered dietary recalls and calculated by using changes in body composition and energy expenditure, moderate-to-vigorous physical activity (MVPA) with the use of an arm-based monitor, body composition with the use of dual-energy X-ray absorptiometry, and questionnaire-derived perceptions of dietary restraint, disinhibition, hunger, and control of eating. Participants were grouped at baseline into quintiles of MVPA (min/d) by sex. Measurements were repeated every 3 mo for 1 y. At baseline, an inverse relation existed between body weight and activity groups, with the least-active group (15.7 ± 9.9 min MVPA/d, 6062 ± 1778 steps/d) having the highest body weight (86.3 ± 13.2 kg) and the most-active group (174.5 ± 60.5 min MVPA/d, 10260 ± 3087 steps/d) having the lowest body weight (67.5 ± 11.0 kg). A positive relation was observed between calculated energy intake and activity group, except in the lowest quintile of activity. The lowest physical activity group reported higher levels of disinhibition (P = 0.07) and cravings for savory foods (P = 0.03) compared with the group with the highest level of physical activity. Over 1 y of follow-up, the lowest activity group gained the largest amount of fat mass (1.7 ± 0.3 kg) after adjustment for change in MVPA and baseline fat mass. The odds of gaining >3% of fat mass were between 1.8 and 3.8 times as high for individuals in the least-active group as for those in the middle activity group. These results suggest that low levels of physical activity are a risk factor for fat mass gain. In the current sample, a threshold for achieving energy balance occurred at an activity level corresponding to 7116 steps/d, an amount achievable by most adults. This trial was registered at clinicaltrials.gov as NCT01746186. © 2015 American Society for Nutrition.
Shook, Robin P; Hand, Gregory A; Drenowatz, Clemens; Hebert, James R; Paluch, Amanda E; Blundell, John E; Hill, James O; Katzmarzyk, Peter T; Church, Timothy S; Blair, Steven N
2015-01-01
Background: Previous studies suggest that appetite may be dysregulated at low levels of activity, creating an energy imbalance that results in weight gain. Objective: The aim was to examine the relation between energy intake, physical activity, appetite, and weight gain during a 1-y follow-up period in a large sample of adults. Design: Participants included 421 individuals (mean ± SD age: 27.6 ± 3.8 y). Measurements included the following: energy intake with the use of interviewer-administered dietary recalls and calculated by using changes in body composition and energy expenditure, moderate-to-vigorous physical activity (MVPA) with the use of an arm-based monitor, body composition with the use of dual-energy X-ray absorptiometry, and questionnaire-derived perceptions of dietary restraint, disinhibition, hunger, and control of eating. Participants were grouped at baseline into quintiles of MVPA (min/d) by sex. Measurements were repeated every 3 mo for 1 y. Results: At baseline, an inverse relation existed between body weight and activity groups, with the least-active group (15.7 ± 9.9 min MVPA/d, 6062 ± 1778 steps/d) having the highest body weight (86.3 ± 13.2 kg) and the most-active group (174.5 ± 60.5 min MVPA/d, 10260 ± 3087 steps/d) having the lowest body weight (67.5 ± 11.0 kg). A positive relation was observed between calculated energy intake and activity group, except in the lowest quintile of activity. The lowest physical activity group reported higher levels of disinhibition (P = 0.07) and cravings for savory foods (P = 0.03) compared with the group with the highest level of physical activity. Over 1 y of follow-up, the lowest activity group gained the largest amount of fat mass (1.7 ± 0.3 kg) after adjustment for change in MVPA and baseline fat mass. The odds of gaining >3% of fat mass were between 1.8 and 3.8 times as high for individuals in the least-active group as for those in the middle activity group. Conclusions: These results suggest that low levels of physical activity are a risk factor for fat mass gain. In the current sample, a threshold for achieving energy balance occurred at an activity level corresponding to 7116 steps/d, an amount achievable by most adults. This trial was registered at clinicaltrials.gov as NCT01746186. PMID:26561620
Optimal migration energetics of humpback whales and the implications of disturbance.
Braithwaite, Janelle E; Meeuwig, Jessica J; Hipsey, Matthew R
2015-01-01
Whales migrate long distances and reproduce on a finite store of energy. Budgeting the use of this limited energy reserve is an important factor to ensure survival over the period of migration and to maximize reproductive investment. For some whales, migration routes are closely associated with coastal areas, exposing animals to high levels of human activity. It is currently unclear how various forms of human activity may disturb whales during migration, how this might impact their energy balance and how this could translate into long-term demographic changes. Here, we develop a theoretical bioenergetic model for migrating humpback whales to investigate the optimal migration strategy that minimizes energy use. The average migration velocity was an important driver of the total energy used by a whale, and an optimal velocity of 1.1 m s(-1) was determined. This optimal velocity is comparable to documented observed migration speeds, suggesting that whales migrate at a speed that conserves energy. Furthermore, the amount of resting time during migration was influenced by both transport costs and feeding rates. We simulated hypothetical disturbances to the optimal migration strategy in two ways, by altering average velocity to represent changes in behavioural activity and by increasing total travelled distance to represent displacement along the migration route. In both cases, disturbance increased overall energy use, with implications for the growth potential of calves.
Optimal migration energetics of humpback whales and the implications of disturbance
Braithwaite, Janelle E.; Meeuwig, Jessica J.; Hipsey, Matthew R.
2015-01-01
Whales migrate long distances and reproduce on a finite store of energy. Budgeting the use of this limited energy reserve is an important factor to ensure survival over the period of migration and to maximize reproductive investment. For some whales, migration routes are closely associated with coastal areas, exposing animals to high levels of human activity. It is currently unclear how various forms of human activity may disturb whales during migration, how this might impact their energy balance and how this could translate into long-term demographic changes. Here, we develop a theoretical bioenergetic model for migrating humpback whales to investigate the optimal migration strategy that minimizes energy use. The average migration velocity was an important driver of the total energy used by a whale, and an optimal velocity of 1.1 m s−1 was determined. This optimal velocity is comparable to documented observed migration speeds, suggesting that whales migrate at a speed that conserves energy. Furthermore, the amount of resting time during migration was influenced by both transport costs and feeding rates. We simulated hypothetical disturbances to the optimal migration strategy in two ways, by altering average velocity to represent changes in behavioural activity and by increasing total travelled distance to represent displacement along the migration route. In both cases, disturbance increased overall energy use, with implications for the growth potential of calves. PMID:27293686
Physical activity and body functionality: implications for obesity prevention and treatment.
Tremblay, Angelo; Therrien, Fanny
2006-02-01
Physical activity promotes metabolic adaptations that improve body functionality and contribute to the prevention of some diseases. With respect to energy and fat balance, physical activity facilitates the equilibrium between energy intake and expenditure as well as between fat intake and fat oxidation. When combined with a healthy diet that favors satiety with a reduced energy intake, exercise can induce a substantial mass loss in obese individuals. However, even the impact of an exemplary lifestyle does not seem to have the potential to decrease body mass in obese individuals down to the mass range of lean people. Up to now, we have not been able to induce mass changes exceeding 12%-15% initial body mass in obese male subjects under tolerable exercise and dietary habits, and this moderate success was accompanied by modifications in appetite and energy expenditure susceptible to compromise subsequent mass stability. As described in this paper, many environmental factors can influence energy balance and the ability to lose body fat in response to a healthy diet and (or) physical activity program. Particular attention is given to preliminary data obtained in our laboratory that suggest that knowledge-based work does not favor the same potential mass reducing effects as physical work. In fact, the acute effects of knowledge-based work suggest that this work modality may be rather susceptible to promote a more pronounced positive energy balance compared with what we may expect from a sedentary relaxing activity. This is problematic for obesity prevention in the future since knowledge-based work now represents the main working modality in a context of modernity.
Rag GTPases mediate amino acid–dependent recruitment of TFEB and MITF to lysosomes
Martina, Jose A.
2013-01-01
The mTORC1 complex supports cell growth and proliferation in response to energy levels, growth factors, and nutrients. The Rag guanosine triphosphatases (GTPases) activate mTORC1 in response to amino acids by promoting its redistribution to lysosomes. In this paper, we identify a novel role for Rags in controlling activation of transcription factor EB (TFEB), a master regulator of autophagic and lysosomal gene expression. Interaction of TFEB with active Rag heterodimers promoted recruitment of TFEB to lysosomes, leading to mTORC1-dependent phosphorylation and inhibition of TFEB. The interaction of TFEB with Rags required the first 30 residues of TFEB and the switch regions of the Rags G domain. Depletion or inactivation of Rags prevented recruitment of TFEB to lysosomes, whereas expression of active Rags induced association of TFEB with lysosomal membranes. Finally, Rag GTPases bound and regulated activation of microphthalmia-associated transcription factor, suggesting a broader role for Rags in the control of gene expression. Our work provides new insight into the molecular mechanisms that link nutrient availability and TFEB localization and activation. PMID:23401004
Malikova, Jana; Camats, Núria; Fernández-Cancio, Mónica; Heath, Karen; González, Isabel; Caimarí, María; del Campo, Miguel; Albisu, Marian; Kolouskova, Stanislava; Audí, Laura; Flück, Christa E.
2014-01-01
Context Human NR5A1/SF-1 mutations cause 46,XY disorder of sex development (DSD) with broad phenotypic variability, and rarely cause adrenal insufficiency although SF-1 is an important transcription factor for many genes involved in steroidogenesis. In addition, the Sf-1 knockout mouse develops obesity with age. Obesity might be mediated through Sf-1 regulating activity of brain-derived neurotrophic factor (BDNF), an important regulator of energy balance in the ventromedial hypothalamus. Objective To characterize novel SF-1 gene variants in 4 families, clinical, genetic and functional studies were performed with respect to steroidogenesis and energy balance. Patients 5 patients with 46,XY DSD were found to harbor NR5A1/SF-1 mutations including 2 novel variations. One patient harboring a novel mutation also suffered from adrenal insufficiency. Methods SF-1 mutations were studied in cell systems (HEK293, JEG3) for impact on transcription of genes involved in steroidogenesis (CYP11A1, CYP17A1, HSD3B2) and in energy balance (BDNF). BDNF regulation by SF-1 was studied by promoter assays (JEG3). Results Two novel NR5A1/SF-1 mutations (Glu7Stop, His408Profs*159) were confirmed. Glu7Stop is the 4th reported SF-1 mutation causing DSD and adrenal insufficiency. In vitro studies revealed that transcription of the BDNF gene is regulated by SF-1, and that mutant SF-1 decreased BDNF promoter activation (similar to steroid enzyme promoters). However, clinical data from 16 subjects carrying SF-1 mutations showed normal birth weight and BMI. Conclusions Glu7Stop and His408Profs*159 are novel SF-1 mutations identified in patients with 46,XY DSD and adrenal insufficiency (Glu7Stop). In vitro, SF-1 mutations affect not only steroidogenesis but also transcription of BDNF which is involved in energy balance. However, in contrast to mice, consequences on weight were not found in humans with SF-1 mutations. PMID:25122490
Malikova, Jana; Camats, Núria; Fernández-Cancio, Mónica; Heath, Karen; González, Isabel; Caimarí, María; del Campo, Miguel; Albisu, Marian; Kolouskova, Stanislava; Audí, Laura; Flück, Christa E
2014-01-01
Human NR5A1/SF-1 mutations cause 46,XY disorder of sex development (DSD) with broad phenotypic variability, and rarely cause adrenal insufficiency although SF-1 is an important transcription factor for many genes involved in steroidogenesis. In addition, the Sf-1 knockout mouse develops obesity with age. Obesity might be mediated through Sf-1 regulating activity of brain-derived neurotrophic factor (BDNF), an important regulator of energy balance in the ventromedial hypothalamus. To characterize novel SF-1 gene variants in 4 families, clinical, genetic and functional studies were performed with respect to steroidogenesis and energy balance. 5 patients with 46,XY DSD were found to harbor NR5A1/SF-1 mutations including 2 novel variations. One patient harboring a novel mutation also suffered from adrenal insufficiency. SF-1 mutations were studied in cell systems (HEK293, JEG3) for impact on transcription of genes involved in steroidogenesis (CYP11A1, CYP17A1, HSD3B2) and in energy balance (BDNF). BDNF regulation by SF-1 was studied by promoter assays (JEG3). Two novel NR5A1/SF-1 mutations (Glu7Stop, His408Profs*159) were confirmed. Glu7Stop is the 4th reported SF-1 mutation causing DSD and adrenal insufficiency. In vitro studies revealed that transcription of the BDNF gene is regulated by SF-1, and that mutant SF-1 decreased BDNF promoter activation (similar to steroid enzyme promoters). However, clinical data from 16 subjects carrying SF-1 mutations showed normal birth weight and BMI. Glu7Stop and His408Profs*159 are novel SF-1 mutations identified in patients with 46,XY DSD and adrenal insufficiency (Glu7Stop). In vitro, SF-1 mutations affect not only steroidogenesis but also transcription of BDNF which is involved in energy balance. However, in contrast to mice, consequences on weight were not found in humans with SF-1 mutations.
NASA Astrophysics Data System (ADS)
Shi, Shuai; Guo, Dan; Luo, Jianbin
2017-10-01
Active quality factor (Q) exhibits many promising properties in dynamic atomic force microscopy. Energy dissipation and image contrasts are investigated in the non-contact amplitude modulation atomic force microscopy (AM-AFM) with an active Q-control circuit in the ambient air environment. Dissipated power and virial were calculated to compare the highly nonlinear interaction of tip-sample and image contrasts with different Q gain values. Greater free amplitudes and lower effective Q values show better contrasts for the same setpoint ratio. Active quality factor also can be employed to change tip-sample interaction force in non-contact regime. It is meaningful that non-destructive and better contrast images can be realized in non-contact AM-AFM by applying an active Q-control to the dynamic system.
Psychosocial predictors of energy underreporting in a large doubly labeled water study.
Tooze, Janet A; Subar, Amy F; Thompson, Frances E; Troiano, Richard; Schatzkin, Arthur; Kipnis, Victor
2004-05-01
Underreporting of energy intake is associated with self-reported diet measures and appears to be selective according to personal characteristics. Doubly labeled water is an unbiased reference biomarker for energy intake that may be used to assess underreporting. Our objective was to determine which factors are associated with underreporting of energy intake on food-frequency questionnaires (FFQs) and 24-h dietary recalls (24HRs). The study participants were 484 men and women aged 40-69 y who resided in Montgomery County, MD. Using the doubly labeled water method to measure total energy expenditure, we considered numerous psychosocial, lifestyle, and sociodemographic factors in multiple logistic regression models for prediction of the probability of underreporting on the FFQ and 24HR. In the FFQ models, fear of negative evaluation, weight-loss history, and percentage of energy from fat were the best predictors of underreporting in women (R(2) = 0.09); body mass index, comparison of activity level with that of others of the same sex and age, and eating frequency were the best predictors in men (R(2) = 0.10). In the 24HR models, social desirability, fear of negative evaluation, body mass index, percentage of energy from fat, usual activity, and variability in number of meals per day were the best predictors of underreporting in women (R(2) = 0.22); social desirability, dietary restraint, body mass index, eating frequency, dieting history, and education were the best predictors in men (R(2) = 0.25). Although the final models were significantly related to underreporting on both the FFQ and the 24HR, the amount of variation explained by these models was relatively low, especially for the FFQ.
Botter, Juliane; Ellegast, Rolf P; Burford, Eva-Maria; Weber, Britta; Könemann, Reinier; Commissaris, Dianne A C M
2016-03-01
Increasing evidence is being found for the association of health risk factors with work-related physical inactivity. An increasing number of people are being exposed to this form of inactivity, and as a result, various interventions aimed at increasing physical activity during working hours are being developed. This study aims to investigate the differences in postural, muscular and physical activities resulting from two dynamic workstations, namely an elliptical trainer and a treadmill workstation, compared with a conventional sitting and standing workstation. Twelve participants completed five standardised office tasks in a laboratory setting at all workstations. No significant effect was found regarding changes in posture and the muscular activity was only significantly higher for the trapezius muscle (50th percentile: 8.1 %MVC) at the dynamic workstations. For the dynamic workstations, physical activity ranged from 4.0 to 14.9 × 10(-2) g, heart rate from 14.3 to 27.5 %HRR and energy expenditure from 1.8 to 3.1 METs. Practitioner Summary: Work-related physical inactivity is associated with health risk factors. In this study, physiological and postural effects of dynamic workstations were assessed in comparison to conventional workstations. No significant effects were found regarding changes in posture and muscular activity. Physical activity, heart rate and energy expenditure increased for the dynamic workstations.
Lee, Du-Hwa; Park, Seung Jun; Ahn, Chang Sook
2017-01-01
Dynamic control of protein translation in response to the environment is essential for the survival of plant cells. Target of rapamycin (TOR) coordinates protein synthesis with cellular energy/nutrient availability through transcriptional modulation and phosphorylation of the translation machinery. However, mechanisms of TOR-mediated translation control are poorly understood in plants. Here, we report that Arabidopsis thaliana MRF (MA3 DOMAIN-CONTAINING TRANSLATION REGULATORY FACTOR) family genes encode translation regulatory factors under TOR control, and their functions are particularly important in energy-deficient conditions. Four MRF family genes (MRF1-MRF4) are transcriptionally induced by dark and starvation (DS). Silencing of multiple MRFs increases susceptibility to DS and treatment with a TOR inhibitor, while MRF1 overexpression decreases susceptibility. MRF proteins interact with eIF4A and cofractionate with ribosomes. MRF silencing decreases translation activity, while MRF1 overexpression increases it, accompanied by altered ribosome patterns, particularly in DS. Furthermore, MRF deficiency in DS causes altered distribution of mRNAs in sucrose gradient fractions and accelerates rRNA degradation. MRF1 is phosphorylated in vivo and phosphorylated by S6 kinases in vitro. MRF expression and MRF1 ribosome association and phosphorylation are modulated by cellular energy status and TOR activity. We discuss possible mechanisms of the function of MRF family proteins under normal and energy-deficient conditions and their functional link with the TOR pathway. PMID:29084871
Electron Acceleration and Efficiency in Nonthermal Gamma-Ray Sources
NASA Astrophysics Data System (ADS)
Bykov, A. M.; Meszaros, P.
1996-04-01
In energetic nonthermal sources such as gamma-ray bursts, active galactic nuclei, or galactic jets, etc., one expects both relativistic and transrelativistic shocks accompanied by violent motions of moderately relativistic plasma. We present general considerations indicating that these sites are electron and positron accelerators leading to a modified power-law spectrum. The electron (or e+/-) energy index is very hard, ~ gamma -1 or flatter, up to a comoving frame break energy gamma *, and becomes steeper above that. In the example of gamma-ray bursts, the Lorentz factor reaches gamma * ~ 103 for e+/- accelerated by the internal shock ensemble on subhydrodynamical timescales. For pairs accelerated on hydrodynamical timescales in the external shocks, similar hard spectra are obtained, and the break Lorentz factor can be as high as gamma * <~ 105. Radiation from the nonthermal electrons produces photon spectra with shapes and characteristic energies in qualitative agreement with observed generic gamma-ray burst and blazar spectra. The scenario described here provides a plausible way to solve one of the crucial problems of nonthermal high-energy sources, namely, the efficient transfer of energy from the proton flow to an appropriate nonthermal lepton component.
A Maternal High-Energy Diet Promotes Intestinal Development and Intrauterine Growth of Offspring
Liu, Peilin; Che, Long; Yang, Zhenguo; Feng, Bin; Che, Lianqiang; Xu, Shengyu; Lin, Yan; Fang, Zhengfeng; Li, Jian; Wu, De
2016-01-01
It has been suggested that maternal nutrition during gestation is involved in an offspring’s intestinal development. The aim of this study was therefore to evaluate the effects of maternal energy on the growth and small intestine development of offspring. After mating, twenty gilts (Large White (LW) breeding, body weight (BW) at 135.54 ± 0.66 kg) were randomly allocated to two dietary treatments: a control diet (CON) group and a high-energy diet (HED) group, respectively. The nutrient levels of the CON were referred to meet the nutrient recommendations by the National Research Council (NRC, 2012), while the HED was designed by adding an amount of soybean oil that was 4.6% of the total diet weight to the CON. The dietary treatments were introduced from day 1 of gestation to farrowing. At day 90 of gestation, day 1 post-birth, and day 28 post-birth, the weights of fetuses and piglets, intestinal morphology, enzyme activities, and gene and protein expressions of intestinal growth factors were determined. The results indicated that the maternal HED markedly increased the BW, small intestinal weight, and villus height of fetuses and piglets. Moreover, the activities of lactase in fetal intestine, sucrase in piglet intestine were markedly increased by the maternal HED. In addition, the maternal HED tended to increase the protein expression of insulin-like growth factor 1 receptor (IGF-1R) in fetal intestine, associated with significantly increased the gene expression of IGF-1R. In conclusion, increasing energy intake could promote fetal growth and birth weight, with greater intestinal morphology and enzyme activities. PMID:27164130
Li, Siming; Mi, Lin; Yu, Lei; Yu, Qi; Liu, Tongyu; Wang, Guo-Xiao; Zhao, Xu-Yun; Wu, Jun
2017-01-01
Brown and beige adipocytes convert chemical energy into heat through uncoupled respiration to defend against cold stress. Beyond thermogenesis, brown and beige fats engage other metabolic tissues via secreted factors to influence systemic energy metabolism. How the protein and long noncoding RNA (lncRNA) regulatory networks act in concert to regulate key aspects of thermogenic adipocyte biology remains largely unknown. Here we developed a genome-wide functional screen to interrogate the transcription factors and cofactors in thermogenic gene activation and identified zinc finger and BTB domain-containing 7b (Zbtb7b) as a potent driver of brown fat development and thermogenesis and cold-induced beige fat formation. Zbtb7b is required for activation of the thermogenic gene program in brown and beige adipocytes. Genetic ablation of Zbtb7b impaired cold-induced transcriptional remodeling in brown fat, rendering mice sensitive to cold temperature, and diminished browning of inguinal white fat. Proteomic analysis revealed a mechanistic link between Zbtb7b and the lncRNA regulatory pathway through which Zbtb7b recruits the brown fat lncRNA 1 (Blnc1)/heterogeneous nuclear ribonucleoprotein U (hnRNPU) ribonucleoprotein complex to activate thermogenic gene expression in adipocytes. These findings illustrate the emerging concept of a protein–lncRNA regulatory network in the control of adipose tissue biology and energy metabolism. PMID:28784777
[Development of special food products for cosmonaut's nutrition during extravehicular activities].
Agureev, A N; Kalandarov, S; Vasil'eva, V F; Gurova, L A
2003-01-01
On the analysis of the factual energy expenditure by cosmonauts during extravehicular activities two choices of special rations (SR) were developed. Hygienic testing showed that all nutritional components in these SRs were present in optimal quantities. Consumption of the SR foods during any basic meal will not misbalance the latter but satisfy the body demand of the main indispensable nutritional factors.
Villa, Roberto Federico; Ferrari, Federica; Gorini, Antonella
2012-12-01
The effect of aging and CDP-choline treatment (20 mg kg⁻¹ body weight i.p. for 28 days) on the maximal rates (V(max)) of representative mitochondrial enzyme activities related to Krebs' cycle (citrate synthase, α-ketoglutarate dehydrogenase, malate dehydrogenase), glutamate and related amino acid metabolism (glutamate dehydrogenase, glutamate-oxaloacetate- and glutamate-pyruvate transaminases) were evaluated in non-synaptic and intra-synaptic "light" and "heavy" mitochondria from frontal cerebral cortex of male Wistar rats aged 4, 12, 18 and 24 months. During aging, enzyme activities vary in a complex way respect to the type of mitochondria, i.e. non-synaptic and intra-synaptic. This micro-heterogeneity is an important factor, because energy-related mitochondrial enzyme catalytic properties cause metabolic modifications of physiopathological significance in cerebral tissue in vivo, also discriminating pre- and post-synaptic sites of action for drugs and affecting tissue responsiveness to noxious stimuli. Results show that CDP-choline in vivo treatment enhances cerebral energy metabolism selectively at 18 months, specifically modifying enzyme catalytic activities in non-synaptic and intra-synaptic "light" mitochondrial sub-populations. This confirms that the observed changes in enzyme catalytic activities during aging reflect the bioenergetic state at each single age and the corresponding energy requirements, further proving that in vivo drug treatment is able to interfere with the neuronal energy metabolism. Copyright © 2012. Published by Elsevier Ltd.
Building Stronger State Partnerships with the US Department of Energy (Energy Assurance)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mike Keogh
2011-09-30
From 2007 until 2011, the National Association of Regulatory Utility Commissioners (NARUC) engaged in a partnership with the National Energy Technology Lab (NETL) to improve State-Federal coordination on electricity policy and energy assurance issues. This project allowed State Public Utility Commissioners and their staffs to engage on the most cutting-edge level in the arenas of energy assurance and electricity policy. Four tasks were outlined in the Statement of Performance Objectives: Task 1 - Training for Commissions on Critical Infrastructure Topics; Task 2 - Analyze and Implement Recommendations on Energy Assurance Issues; Task 3 - Ongoing liaison activities & outreach tomore » build stronger networks between federal agencies and state regulators; and Task 4 - Additional Activities. Although four tasks were prescribed, in practice these tasks were carried out under two major activity areas: the critical infrastructure and energy assurance partnership with the US Department of Energy's Infrastructure Security and Emergency Response office, and the National Council on Electricity Policy, a collaborative which since 1994 has brought together State and Federal policymakers to address the most pressing issues facing the grid from restructuring to smart grid implementation. On Critical Infrastructure protection, this cooperative agreement helped State officials yield several important advances. The lead role on NARUC's side was played by our Committee on Critical Infrastructure Protection. Key lessons learned in this arena include the following: (1) Tabletops and exercises work - They improve the capacity of policymakers and their industry counterparts to face the most challenging energy emergencies, and thereby equip these actors with the capacity to face everything up to that point as well. (2) Information sharing is critical - Connecting people who need information with people who have information is a key success factor. However, exposure of critical infrastructure information to bad actors also creates new vulnerabilities. (3) Tensions exist between the transparency-driven basis of regulatory activity and the information-protection requirements of asset protection. (4) Coordination between states is a key success factor - Because comparatively little federal authority exists over electricity and other energy infrastructure, the interstate nature of these energy grids defy centralized command and control governance. Patchwork responses are a risk when addressed at a state-by-state level. Coordination is the key to ensuring consistent response to shared threats. In Electricity Policy, the National Council on Electricity Policy continued to make important strides forward. Coordinated electricity policy among States remains the best surrogate for an absent national electricity policy. In every area from energy efficiency to clean coal, State policies are driving the country's electricity policy, and regional responses to climate change, infrastructure planning, market operation, and new technology deployment depend on a forum for bringing the States together.« less
Ismail, M N; Chee, S S; Nawawi, H; Yusoff, K; Lim, T O; James, W P T
2002-08-01
This study was undertaken to assess the recent data on Malaysian adult body weights and associations of ethnic differences in overweight and obesity with comorbid risk factors, and to examine measures of energy intake, energy expenditure, basal metabolic rate (BMR) and physical activity changes in urban and rural populations of normal weight. Three studies were included (1) a summary of a national health morbidity survey conducted in 1996 on nearly 29 000 adults > or =20 years of age; (2) a study comparing energy intake, BMR and physical activity levels (PALs) in 409 ethnically diverse, healthy adults drawn from a population of 1165 rural and urban subjects 18-60 years of age; and (3) an examination of the prevalence of obesity and comorbid risk factors that predict coronary heart disease and type 2 diabetes in 609 rural Malaysians aged 30-65 years. Overweight and obesity were calculated using body mass index (BMI) measures and World Health Organization (WHO) criteria. Energy intake was assessed using 3-d food records, BMR and PALs were assessed with Douglas bags and activity diaries, while hypertension, hyperlipidaemia and glucose intolerance were specified using standard criteria. The National Health Morbidity Survey data revealed that in adults, 20.7% were overweight and 5.8% obese (0.3% of whom had BMI values of >40.0 kg m(-2)); the prevalence of obesity was clearly greater in women than in men. In women, obesity rates were higher in Indian and Malay women than in Chinese women, while in men the Chinese recorded the highest obesity prevalences followed by the Malay and Indians. Studies on normal healthy subjects indicated that the energy intake of Indians was significantly lower than that of other ethnic groups. In women, Malays recorded a significantly higher energy intake than the other groups. Urban male subjects consumed significantly more energy than their rural counterparts, but this was not the case in women. In both men and women, fat intakes (%) were significantly higher in Chinese and urban subjects. Men were moderately active with the exception of the Dayaks. Chinese women were considerably less active than Chinese men. Chinese and Dayak women were less active than Malay and Indian women. In both men and women, Indians recorded the highest PALs. Hence, current nutrition and health surveys reveal that Malaysians are already affected by western health problems. The escalation of obesity, once thought to be an urban phenomenon, has now spread to the rural population at an alarming rate. As Malaysia proceeds rapidly towards a developed economy status, the health of its population will probably continue to deteriorate. Therefore, a national strategy needs to be developed to tackle both dietary and activity contributors to the excess weight gain of the Malaysian population.
An energy- and depth-dependent model for x-ray imaging
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gallas, Brandon D.; Boswell, Jonathan S.; Badano, Aldo
In this paper, we model an x-ray imaging system, paying special attention to the energy- and depth-dependent characteristics of the inputs and interactions: x rays are polychromatic, interaction depth and conversion to optical photons is energy-dependent, optical scattering and the collection efficiency depend on the depth of interaction. The model we construct is a random function of the point process that begins with the distribution of x rays incident on the phosphor and ends with optical photons being detected by the active area of detector pixels to form an image. We show how the point-process representation can be used tomore » calculate the characteristic statistics of the model. We then simulate a Gd{sub 2}O{sub 2}S:Tb phosphor, estimate its characteristic statistics, and proceed with a signal-detection experiment to investigate the impact of the pixel fill factor on detecting spherical calcifications (the signal). The two extremes possible from this experiment are that SNR{sup 2} does not change with fill factor or changes in proportion to fill factor. In our results, the impact of fill factor is between these extremes, and depends on the diameter of the signal.« less
Stress, behavior, and biology: Risk factors for cardiovascular diseases in youth
USDA-ARS?s Scientific Manuscript database
Psychological stress is associated with cardiovascular disease (CVD) pathogenesis during childhood. Stress promotes atherogenic behaviors in children including snacking of energy dense foods and reduced physical activity; and it also increases adiposity. Stress-induced CV reactivity may also be athe...
Stress, behavior, and biology: Risk factors for cardiovascular disease in youth
USDA-ARS?s Scientific Manuscript database
Psychological stress is associated with cardiovascular disease (CVD) pathogenesis during childhood. Stress promotes atherogenic behaviors in children including snacking of energy dense foods and reduced physical activity; and it also increases adiposity. Stress-induced CV reactivity may also be athe...
SIRT3 aggravates metformin-induced energy stress and apoptosis in ovarian cancer cells.
Wu, Yao; Gao, Wei-Nan; Xue, Ya-Nan; Zhang, Li-Chao; Zhang, Juan-Juan; Lu, Sheng-Yao; Yan, Xiao-Yu; Yu, Hui-Mei; Su, Jing; Sun, Lian-Kun
2018-06-15
Increasing evidence suggests that mitochondrial respiratory chain complex I participates in carcinogenesis and cancer progression by providing energy and maintaining mitochondrial function. However, the role of complex I in ovarian cancer is largely unknown. In this study we showed that metformin, considered to be an inhibitor of complex I, simultaneously inhibited cell growth and induced mitochondrial-related apoptosis in human ovarian cancer cells. Metformin interrupted cellular energy metabolism mainly by causing damage to complex I that impacted mitochondrial function. Additionally, treatment with metformin increased the activation of sirtuin 3 (SIRT3), a mitochondrial deacetylase. We demonstrated that SIRT3 overexpression aggravated metformin-induced apoptosis, energy stress and mitochondrial dysfunction. Moreover, treatment with metformin or SIRT3 overexpression increased activation of AMP-activated protein kinase (AMPK), a major sensor of cellular energy status. AMPK compensated for energy loss by increasing glycolysis. The impact of this was assessed by reducing glucose levels in the media or by using inhibitors (2-deoxyglucose, Compound C) of glycolysis and AMPK. The combination of these factors with metformin intensified cytotoxicity through further downregulation of ATP. Our study outlines an important role for SIRT3 in the antitumor effect of mitochondrial complex I inhibitors in human ovarian cancer cells. This effect appears to be mediated by induction of energy stress and apoptosis. Strategies that target the mitochondria could be enhanced by modulating glycolysis to further aggravate energy stress that may increase the antitumor effect. Copyright © 2018 Elsevier Inc. All rights reserved.
Concannon, Caoimhín G.; Tuffy, Liam P.; Weisová, Petronela; Bonner, Helena P.; Dávila, David; Bonner, Caroline; Devocelle, Marc C.; Strasser, Andreas; Ward, Manus W.
2010-01-01
Excitotoxicity after glutamate receptor overactivation induces disturbances in cellular ion gradients, resulting in necrosis or apoptosis. Excitotoxic necrosis is triggered by rapid, irreversible ATP depletion, whereas the ability to recover cellular bioenergetics is suggested to be necessary for the activation of excitotoxic apoptosis. In this study, we demonstrate that even a transient decrease in cellular bioenergetics and an associated activation of adenosine monophosphate–activated protein kinase (AMPK) is necessary for the activation of excitotoxic apoptosis. We show that the Bcl-2 homology domain 3 (BH3)–only protein Bim, a proapoptotic Bcl-2 family member, is activated in multiple excitotoxicity paradigms, mediates excitotoxic apoptosis, and inhibits delayed Ca2+ deregulation, mitochondrial depolarization, and apoptosis-inducing factor translocation. We demonstrate that bim activation required the activation of AMPK and that prolonged AMPK activation is sufficient to induce bim gene expression and to trigger a bim-dependent cell death. Collectively, our data demonstrate that AMPK activation and the BH3-only protein Bim couple transient energy depletion to stress-induced neuronal apoptosis. PMID:20351066
Energy requirements of man living in a weightless environment.
Vanderveen, J E; Allen, T H
1972-01-01
The ability to maintain energy balance is a vital factor in maintaining body composition. A negative energy balance requires that body tissue be consumed to sustain biochemical and physiological activity. Such a caloric imbalance coupled with reduced physical activity results in (among other things): a negative balance which can not be reversed by increased protein intake; negative balances for electrolytes; and a suspension of erythrocyte production. Body weight losses were experienced by all astronauts during Gemini and Apollo missions. Data on the magnitude of the changes, together with data on energy consumption, were used to calculate energy imbalances. These data, when compared with results obtained from precise energy balance measurements made on 64 men living in low pressure chambers, show close correlation. When energy requirements are expressed in kilocalories per kilogram of body weight, the difference in energy requirements among the astronauts and chamber subjects was small and not statistically significant. These data indicated that reliable prediction of energy needs for astronauts, during long-term space missions, can be made by studying either the astronauts or healthy subjects in a ground-based environment similar to that of the spacecraft. These data also indicate that changes in body weight and certain other body measurements detected during Gemini and Apollo missions were probably caused, at least in part, by a calorie deficit.
High-performance sodium–organic battery by realizing four-sodium storage in disodium rhodizonate
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lee, Minah; Hong, Jihyun; Lopez, Jeffrey
Sodium-ion batteries (SIBs) for grid-scale applications need active materials that combine a high energy density with sustainability. Given the high theoretical specific capacity 501 mAh g -1, and Earth abundance of disodium rhodizonate (Na 2C 6O 6), it is one of the most promising cathodes for SIBs. However, substantially lower reversible capacities have been obtained compared with the theoretical value and the understanding of this discrepancy has been limited. In this paper, we reveal that irreversible phase transformation of Na 2C 6O 6 during cycling is the origin of the deteriorating redox activity of Na 2C 6O 6. The active-particlemore » size and electrolyte conditions were identified as key factors to decrease the activation barrier of the phase transformation during desodiation. Finally, on the basis of this understanding, we achieved four-sodium storage in a Na 2C 6O 6 electrode with a reversible capacity of 484 mAh g -1, an energy density of 726 Wh kg -1 cathode, an energy efficiency above 87% and a good cycle retention.« less
Microglia activation due to obesity programs metabolic failure leading to type two diabetes
Maldonado-Ruiz, R; Montalvo-Martínez, L; Fuentes-Mera, L; Camacho, A
2017-01-01
Obesity is an energy metabolism disorder that increases susceptibility to the development of metabolic diseases. Recently, it has been described that obese subjects have a phenotype of chronic inflammation in organs that are metabolically relevant for glucose homeostasis and energy. Altered expression of immune system molecules such as interleukins IL-1, IL-6, IL-18, tumor necrosis factor alpha (TNF-α), serum amyloid A (SAA), and plasminogen activator inhibitor-1 (PAI-1), among others, has been associated with the development of chronic inflammation in obesity. Chronic inflammation modulates the development of metabolic-related comorbidities like metabolic syndrome (insulin resistance, glucose tolerance, hypertension and hyperlipidemia). Recent evidence suggests that microglia activation in the central nervous system (CNS) is a priority in the deregulation of energy homeostasis and promotes increased glucose levels. This review will cover the most significant advances that explore the molecular signals during microglia activation and inflammatory stage in the brain in the context of obesity, and its influence on the development of metabolic syndrome and type two diabetes. PMID:28319103
High-performance sodium–organic battery by realizing four-sodium storage in disodium rhodizonate
Lee, Minah; Hong, Jihyun; Lopez, Jeffrey; ...
2017-10-09
Sodium-ion batteries (SIBs) for grid-scale applications need active materials that combine a high energy density with sustainability. Given the high theoretical specific capacity 501 mAh g -1, and Earth abundance of disodium rhodizonate (Na 2C 6O 6), it is one of the most promising cathodes for SIBs. However, substantially lower reversible capacities have been obtained compared with the theoretical value and the understanding of this discrepancy has been limited. In this paper, we reveal that irreversible phase transformation of Na 2C 6O 6 during cycling is the origin of the deteriorating redox activity of Na 2C 6O 6. The active-particlemore » size and electrolyte conditions were identified as key factors to decrease the activation barrier of the phase transformation during desodiation. Finally, on the basis of this understanding, we achieved four-sodium storage in a Na 2C 6O 6 electrode with a reversible capacity of 484 mAh g -1, an energy density of 726 Wh kg -1 cathode, an energy efficiency above 87% and a good cycle retention.« less
High-performance sodium-organic battery by realizing four-sodium storage in disodium rhodizonate
NASA Astrophysics Data System (ADS)
Lee, Minah; Hong, Jihyun; Lopez, Jeffrey; Sun, Yongming; Feng, Dawei; Lim, Kipil; Chueh, William C.; Toney, Michael F.; Cui, Yi; Bao, Zhenan
2017-11-01
Sodium-ion batteries (SIBs) for grid-scale applications need active materials that combine a high energy density with sustainability. Given the high theoretical specific capacity 501 mAh g-1, and Earth abundance of disodium rhodizonate (Na2C6O6), it is one of the most promising cathodes for SIBs. However, substantially lower reversible capacities have been obtained compared with the theoretical value and the understanding of this discrepancy has been limited. Here, we reveal that irreversible phase transformation of Na2C6O6 during cycling is the origin of the deteriorating redox activity of Na2C6O6. The active-particle size and electrolyte conditions were identified as key factors to decrease the activation barrier of the phase transformation during desodiation. On the basis of this understanding, we achieved four-sodium storage in a Na2C6O6 electrode with a reversible capacity of 484 mAh g-1, an energy density of 726 Wh kg-1cathode, an energy efficiency above 87% and a good cycle retention.
de Assis da Silva, Rafael; Mograbi, Daniel C; Camelo, Evelyn V M; Morton, Gregory Duff; Landeira-Fernandez, J; Cheniaux, Elie
2015-06-01
In the last few decades, several tools for studying insight in bipolar disorders have been used. Olaya and colleagues developed the Insight Scale for Affective Disorders (ISAD), which consists of a scale measuring insight through hetero evaluation for patients with mood disorders. The objective of this work is to translate and adapt the original English version of the ISAD to Brazilian Portuguese (ISAD-BR) and to conduct an evaluation of its psychometric properties. Adaptation procedures included translation/back-translation and consultation with a panel of experts. 95 patients with the diagnosis of Type 1 bipolar disorder were evaluated with the final version of the ISAD-BR, which was applied, simultaneously, but independently, by two examiners. Internal consistency and inter-rater reliability were explored and the latent structure of the scale was investigated with principal axis factoring and promax rotation. A second-order factor analysis was conducted to test if the scale had a hierarchical factor structure. The ISAD-BR showed good internal consistency and good inter-rater reliability. The analysis pointed to a four-factor solution of the ISAD-BR: awareness of symptoms associated with activity/energy; awareness of having a disorder; awareness of self-esteem and feelings of pleasure; and awareness of social functioning and relationships. The second order factor analysis indicated a hierarchical factor structure for the ISAD-BR, with the four lower-order factors loading on a single higher-order factor. Insight into bipolar disorder is a multidimensional construct, covering different aspects of the condition and its symptomatology. Nevertheless, insight about activity/energy changes may be a crucial aspect of insight into bipolar disorder. Copyright © 2015 Elsevier B.V. All rights reserved.
Work factors are associated with workplace activity limitations in systemic lupus erythematosus.
Al Dhanhani, Ali M; Gignac, Monique A M; Beaton, Dorcas E; Su, Jiandong; Fortin, Paul R
2014-11-01
The objective of this study was to examine the extent of workplace activity limitations among persons with lupus and to identify factors associated with activity limitations among those employed. We conducted a cross-sectional study using a mailed survey and clinical data of persons with lupus who attended a large lupus outpatient clinic. Data were collected on demographics, health, work factors and psychosocial measures. The workplace activity limitations scale (WALS) was used to measure difficulty related to different activities at work. Multivariable analysis examined the association of health, work context, psychosocial and demographic variables with workplace activity limitations. We received 362 responses from 604 (60%) mailed surveys. Among those not employed, 52% reported not working because of lupus. A range of physical and mental tasks were reported as difficult. Each of the physical, cognitive and energy work activities was cited as difficult by more than one-third of participants. Among employed participants, 40% had medium to high WALS difficulty scores. In the multivariable analysis, factors significantly associated with workplace activity limitations were older age, greater disease activity, fatigue, poorer health status measured by the 36-item Short Form Health Survey, lower job control, greater job strain and working more than 40 h/week. People with lupus experience limitations and difficulty at work. Determinants of workplace activity limitations are mainly those related to workplace and health factors. © The Author 2014. Published by Oxford University Press on behalf of the British Society for Rheumatology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mankuzhiyil, Nijil; Ansoldi, Stefano; Persic, Massimo
2011-05-20
For the high-frequency-peaked BL Lac object Mrk 421, we study the variation of the spectral energy distribution (SED) as a function of source activity, from quiescent to active. We use a fully automatized {chi}{sup 2}-minimization procedure, instead of the 'eyeball' procedure more commonly used in the literature, to model nine SED data sets with a one-zone synchrotron self-Compton (SSC) model and examine how the model parameters vary with source activity. The latter issue can finally be addressed now, because simultaneous broadband SEDs (spanning from optical to very high energy photon) have finally become available. Our results suggest that in Mrkmore » 421 the magnetic field (B) decreases with source activity, whereas the electron spectrum's break energy ({gamma}{sub br}) and the Doppler factor ({delta}) increase-the other SSC parameters turn out to be uncorrelated with source activity. In the SSC framework, these results are interpreted in a picture where the synchrotron power and peak frequency remain constant with varying source activity, through a combination of decreasing magnetic field and increasing number density of {gamma} {<=} {gamma}{sub br} electrons: since this leads to an increased electron-photon scattering efficiency, the resulting Compton power increases, and so does the total (= synchrotron plus Compton) emission.« less
NASA Technical Reports Server (NTRS)
Wade, C. E.; Moran, M. M.; Stein, T. P.; Sin, Sidney (Technical Monitor)
2001-01-01
With the increase in obesity related diseases there is heightened interest in mechanisms regulating body weight. To assess the influence of increases in body weight on energy expenditure and intake in rats we employed variable levels of gravity. Our approach afforded the means to measure interactions of energy expenditure and intake in response to increases in body weight (body mass x gravity level). We found a dose relationship between rapid elevation of body weight and reduction of voluntary movement, such that the energy requirements for activity are unchanged, and total energy expenditure and intake maintained. Reduction of movement appears to be a response to increased body weight, rather than a contributing factor, suggesting a new regulatory pathway.
Zhu, Zongjian; Jiang, Weiqin; Zacher, Jarrod H; Neil, Elizabeth S; McGinley, John N; Thompson, Henry J
2012-03-01
Limiting energy availability via diet or physical activity has health benefits; however, it is not known whether these interventions have similar effects on the development of cancer. Two questions were addressed as follows: (i) Does limiting energy availability by increasing physical activity have the same effect on mammary carcinogenesis as limiting caloric intake? and (ii) Are host systemic factors, implicated as risk biomarkers for breast cancer, similarly affected by these interventions? Female Sprague Dawley rats were injected with 50-mg 1-methyl-1-nitrosourea per kg body weight at 21 days of age and randomized to one of five groups (30 rats per group) as follows: (i) sham running wheel control; (ii) restricted fed to 85% of the sham control; (iii and iv) voluntary running in a motorized activity wheel (37 m/min) to a maximum of 3,500 m/d or 1,750 m/d; and (v) sedentary ad libitum fed control with no access to a running wheel. The three energetics interventions inhibited the carcinogenic response, reducing cancer incidence (P = 0.01), cancer multiplicity (P < 0.001), and cancer burden (P < 0.001) whereas prolonging cancer latency (P = 0.004) although differences among energetics interventions were not significant. Of the plasma biomarkers associated with the development of cancer, the energetics interventions reduced bioavailable insulin-like growth factor-1 (IGF-1), insulin, interleukin-6, serum amyloid protein, TNF-α, and leptin and increased IGF-binding protein 3 (IGFBP-3) and adiponectin. Plasma-fasting glucose, C-reactive protein, estradiol, and progesterone were unaffected. The plasma biomarkers of greatest value in predicting the carcinogenic response were adiponectin > IGF-1/IGFBP-3 > IGFBP-3 > leptin > IGF-1.
NRF2 Orchestrates the Metabolic Shift during Induced Pluripotent Stem Cell Reprogramming
Hawkins, Kate E.; Joy, Shona; Delhove, Juliette M.K.M.; Kotiadis, Vassilios N.; Fernandez, Emilio; Fitzpatrick, Lorna M.; Whiteford, James R.; King, Peter J.; Bolanos, Juan P.; Duchen, Michael R.; Waddington, Simon N.; McKay, Tristan R.
2016-01-01
Summary The potential of induced pluripotent stem cells (iPSCs) in disease modeling and regenerative medicine is vast, but current methodologies remain inefficient. Understanding the cellular mechanisms underlying iPSC reprogramming, such as the metabolic shift from oxidative to glycolytic energy production, is key to improving its efficiency. We have developed a lentiviral reporter system to assay longitudinal changes in cell signaling and transcription factor activity in living cells throughout iPSC reprogramming of human dermal fibroblasts. We reveal early NF-κB, AP-1, and NRF2 transcription factor activation prior to a temporal peak in hypoxia inducible factor α (HIFα) activity. Mechanistically, we show that an early burst in oxidative phosphorylation and elevated reactive oxygen species generation mediates increased NRF2 activity, which in turn initiates the HIFα-mediated glycolytic shift and may modulate glucose redistribution to the pentose phosphate pathway. Critically, inhibition of NRF2 by KEAP1 overexpression compromises metabolic reprogramming and results in reduced efficiency of iPSC colony formation. PMID:26904936
Training response inhibition to food is associated with weight loss and reduced energy intake
Lawrence, Natalia S.; O'Sullivan, Jamie; Parslow, David; Javaid, Mahmood; Adams, Rachel C.; Chambers, Christopher D.; Kos, Katarina; Verbruggen, Frederick
2015-01-01
The majority of adults in the UK and US are overweight or obese due to multiple factors including excess energy intake. Training people to inhibit simple motor responses (key presses) to high-energy density food pictures reduces intake in laboratory studies. We examined whether online response inhibition training reduced real-world food consumption and weight in a community sample of adults who were predominantly overweight or obese (N = 83). Participants were allocated in a randomised, double-blind design to receive four 10-min sessions of either active or control go/no-go training in which either high-energy density snack foods (active) or non-food stimuli (control) were associated with no-go signals. Participants' weight, energy intake (calculated from 24-h food diaries), daily snacking frequency and subjective food evaluations were measured for one week pre- and post-intervention. Participants also provided self-reported weight and monthly snacking frequency at pre-intervention screening, and one month and six months after completing the study. Participants in the active relative to control condition showed significant weight loss, reductions in daily energy intake and a reduction in rated liking of high-energy density (no-go) foods from the pre-to post-intervention week. There were no changes in self-reported daily snacking frequency. At longer-term follow-up, the active group showed significant reductions in self-reported weight at six months, whilst both groups reported significantly less snacking at one- and six-months. Excellent rates of adherence (97%) and positive feedback about the training suggest that this intervention is acceptable and has the potential to improve public health by reducing energy intake and overweight. PMID:26122756
Activation energies of diffusion of organic migrants in cyclo olefin polymer.
Welle, Frank
2014-10-01
Cyclo olefin polymer (COP) is an amorphous polymer with good optical transparency and barrier properties, which is increasingly used for pharmaceutical packaging applications like pre-filled syringes, plastic vials, nutrition bags and blisters as well as for micro-well plates. For regulatory purposes, it is important to know the amount and quantity of compounds which migrate from the polymer into the pharmaceutical product. Within the study, diffusion coefficients of organic (model) compounds in COP at various temperatures were determined and the activation energies of diffusion were calculated according to the Arrhenius approach. Correlations were established between the molecular volume V of the migrating compound and the activation energy of diffusion EA as well as between the pre-exponential factor in the Arrhenius equation D0 and EA. From these correlations a prediction model was established for the migration of organic compounds in COP. This might be a useful tool supporting the evaluation process of COP packed pharmaceutical products. Copyright © 2014 Elsevier B.V. All rights reserved.
Coal char oxidation kinetics in air medium
NASA Astrophysics Data System (ADS)
Slyusarskiy, K. V.; Jankovskiy, S. A.; Korotkikh, A. G.; Sorokin, I. V.
2017-01-01
Research on oxidation in air medium process of three different coal chars with various carbon content was presented. The anthracite, T-grade bituminous coal and 2B-grade lignite char powders with particle size less than 80 µm were studied. The coal char oxidation was studied by isothermal method using coupled TG-DSC analyzer Netzsch STA 449 Jupiter F3 in the temperature range 1000-1200 °C. Experiments were carried out at ambient pressure. Volumetric flow rate of oxidation medium into analyzer chamber was 250 ml/min and consisted of oxygen and argon with volumetric ratio 24:1. Based on experimental data, the average rate of carbon oxidation reaction values were defined at each temperature. Kinetic constants (frequency factor and activation energy) of reaction were defined as well via 1st order Arrhenius equation. Activation energy values are in good agreement with the data presented in the literature. Activation energy values for anthracite char are 1.6-1.7 times higher than those for bituminous coal and lignite chars, respectively.
Molecular dynamics study of strain-induced diffusivity of nitrogen in pure iron nanocrystalline
NASA Astrophysics Data System (ADS)
Mohammadzadeh, Roghayeh; Razmara, Naiyer; Razmara, Fereshteh
2016-12-01
In the present study, the self-diffusion process of nitrogen in pure iron nanocrystalline under strain conditions has been investigated by Molecular Dynamics (MD). The interactions between particles are modeled using Modified Embedded Atom Method (MEAM). Mean Square Displacement (MSD) of nitrogen in iron structure under strain is calculated. Strain is applied along [ 11 2 ¯ 0 ] and [ 0001 ] directions in both tensile and compression conditions. The activation energy and pre-exponential diffusion factor for nitrogen diffusion is comparatively high along [ 0001 ] direction of compressed structure of iron. The strain-induced diffusion coefficient at 973 K under the compression rate of 0.001 Å/ps along [ 0001 ] direction is about 6.72E-14 m2/s. The estimated activation energy of nitrogen under compression along [ 0001 ] direction is equal to 12.39 kcal/mol. The higher activation energy might be due to the fact that the system transforms into a more dense state when compressive stress is applied.
Dietary recommendations and athletic menstrual dysfunction.
Manore, Melinda M
2002-01-01
Exercise-induced or athletic menstrual dysfunction (amenorrhoea, oligomenorrhoea, anovulation, luteal phase deficiency, delayed menarche) is more common in active women and can significantly affect health and sport performance. Although athletic amenorrhoea represents the most extreme form of menstrual dysfunction, other forms can also result in suppressed estrogen levels and affect bone health and fertility. A number of factors, such as energy balance, exercise intensity and training practices, bodyweight and composition, disordered eating behaviours, and physical and emotional stress levels, may contribute to the development of athletic menstrual dysfunction. There also appears to be a high degree of individual variation with respect to the susceptibility of the reproductive axis to exercise and diet-related stresses. The dietary issues of the female athlete with athletic menstrual dysfunction are similar to those of her eumenorrhoeic counterpart. The most common nutrition issues in active women are poor energy intake and/or poor food selection, which can lead to poor intakes of protein, carbohydrate and essential fatty acids. The most common micronutrients to be low are the bone-building nutrients, especially calcium, the B vitamins, iron and zinc. If energy drain is the primary contributing factor to athletic menstrual dysfunction, improved energy balance will improve overall nutritional status and may reverse the menstrual dysfunction, thus returning the athlete to normal reproductive function. Because bone health can be compromised in female athletes with menstrual dysfunction, intakes of bone-building nutrients are especially important. Iron and zinc are typically low in the diets of female athletes if meat products are avoided. Adequate intake of the B vitamins is also important to ensure adequate energy production and the building and repair of muscle tissue. This review briefly discusses the various factors that may affect athletic menstrual dysfunction and two of the proposed mechanisms: the energy-drain and exercise-intensity hypotheses. Because energy drain can be a primary contributor to athletic menstrual dysfunction, recommendations for energy and the macro- and micronutrients are reviewed. Methods for helping the female athlete to reverse athletic menstrual dysfunction are discussed. The health consequences of trying to restrict energy intake too dramatically while training are also reviewed, as is the importance of screening athletes for disordered eating. Vitamins and minerals of greatest concern for the female athlete are addressed and recommendations for intake are given.
Melby, Christopher L.; Paris, Hunter L.; Foright, Rebecca M.; Peth, James
2017-01-01
Metabolic adaptations occur with weight loss that result in increased hunger with discordant simultaneous reductions in energy requirements—producing the so-called energy gap in which more energy is desired than is required. The increased hunger is associated with elevation of the orexigenic hormone ghrelin and decrements in anorexigenic hormones. The lower total daily energy expenditure with diet-induced weight loss results from (1) a disproportionately greater decrease in circulating leptin and resting metabolic rate (RMR) than would be predicted based on the decline in body mass, (2) decreased thermic effect of food (TEF), and (3) increased energy efficiency at work intensities characteristic of activities of daily living. These metabolic adaptations can readily promote weight regain. While more experimental research is needed to identify effective strategies to narrow the energy gap and attenuate weight regain, some factors contributing to long-term weight loss maintenance have been identified. Less hunger and greater satiation have been associated with higher intakes of protein and dietary fiber, and lower glycemic load diets. High levels of physical activity are characteristic of most successful weight maintainers. A high energy flux state characterized by high daily energy expenditure and matching energy intake may attenuate the declines in RMR and TEF, and may also result in more accurate regulation of energy intake to match daily energy expenditure. PMID:28481261
Energy Innovation Clusters and their Influence on Manufacturing: A Case Study Perspective
DOE Office of Scientific and Technical Information (OSTI.GOV)
Engel-Cox, Jill; Hill, Derek
Innovation clusters have been important for recent development of clean energy technologies and their emergence as mature, globally competitive industries. However, the factors that influence the co-location of manufacturing activities with innovation clusters are less clear. A central question for government agencies seeking to grow manufacturing as part of economic development in their location is how innovation clusters influence manufacturing. Thus, this paper examines case studies of innovation clusters for three different clean energy technologies that have developed in at least two locations: solar PV clusters in California and the province of Jiangsu in China, wind turbine clusters in Germanymore » and the U.S. Great Lakes region, and ethanol clusters in the U.S. Midwest and the state of Sao Paulo in Brazil. These case studies provide initial insight into factors and conditions that contribute to technology manufacturing facility location decisions.« less
Haghighi Mood, Kaveh; Lüchow, Arne
2017-08-17
Diffusion quantum Monte Carlo calculations with partial and full optimization of the guide function are carried out for the dissociation of the FeS molecule. For the first time, quantum Monte Carlo orbital optimization for transition metal compounds is performed. It is demonstrated that energy optimization of the orbitals of a complete active space wave function in the presence of a Jastrow correlation function is required to obtain agreement with the experimental dissociation energy. Furthermore, it is shown that orbital optimization leads to a 5 Δ ground state, in agreement with experiments but in disagreement with other high-level ab initio wave function calculations which all predict a 5 Σ + ground state. The role of the Jastrow factor in DMC calculations with pseudopotentials is investigated. The results suggest that a large Jastrow factor may improve the DMC accuracy substantially at small additional cost.
Effects of the menopausal transition on energy expenditure: a MONET Group Study.
Duval, K; Prud'homme, D; Rabasa-Lhoret, R; Strychar, I; Brochu, M; Lavoie, J-M; Doucet, E
2013-04-01
Factors that influence weight gain during the menopausal transition are not fully understood. The purpose of this study was to investigate changes in energy expenditure (EE) across the menopausal transition. In all, 102 premenopausal women (age: 49.9 ± 1.9 years; body mass index: 23.3 ± 2.2 kg/m(2)) were followed for 5 years. Body composition (dual-energy X-ray absorptiometry), physical activity EE (accelerometer), resting EE and thermic effect of food (indirect calorimetry) were measured annually. Total EE decreased significantly over time in postmenopausal women (P<0.05), which was mostly due to a decrease in physical activity EE (P<0.05). Although average resting EE remained stable over time in postmenopausal women, a significant increase, over the 5-year period, was noted in women who were in the menopausal transition by year 5 (P<0.05). Finally, the time spent in moderate physical activity decreased and the time spent in sedentary physical activity increased during the menopausal transition (P<0.05). These results suggest that menopausal transition is accompanied with a decline in EE mainly characterized by a decrease in physical activity EE and a shift to a more sedentary lifestyle.
Grochowska, Ewa; Jarzyna, Robert
2014-09-12
In developed countries, we can observe an increasing number of people with obesity, type 2 diabetes, dyslipidemia, hypertension and arteriosclerosis. The main reason for this phenomenon is the abnormal energy balance due to sedentary lifestyles. Cardiovascular diseases are the leading cause of death in many countries around the world, nowadays. In this paper, the impact of physical activity on the effectiveness of treatment and prevention of metabolic diseases and cancer is considered. Exercise is one of the factors activating 5'AMP-activated protein kinase (AMPK). This enzyme is crucial in maintaining the energy balance of the cell and the entire organism, and its activation results in excluding the anabolic and switching on the catabolic processes. It is believed that the activation of AMPK is responsible for most of the positive effects resulting from physical exercise. Although there are pharmacological methods of activation of this enzyme, they seem to be not as effective as physical exercise. Therefore, physical activity should be the most important form of prevention and treatment of metabolic diseases.
Energy requirements of adult dogs: a meta-analysis.
Bermingham, Emma N; Thomas, David G; Cave, Nicholas J; Morris, Penelope J; Butterwick, Richard F; German, Alexander J
2014-01-01
A meta-analysis was conducted to determine the maintenance energy requirements of adult dogs. Suitable publications were first identified, and then used to generate relationships amongst energy requirements, husbandry, activity level, methodology, sex, neuter status, dog size, and age in healthy adult dogs. Allometric equations for maintenance energy requirements were determined using log-log linear regression. So that the resulting equations could readily be compared with equations reported by the National Research Council, maintenance energy requirements in the current study were determined in kcal/kg(0.75) body weight (BW). Ultimately, the data of 70 treatment groups from 29 publications were used, and mean (± standard deviation) maintenance energy requirements were 142.8±55.3 kcal·kgBW(-0.75)·day(-1). The corresponding allometric equation was 81.5 kcal·kgBW(-0.9)·day(-1) (adjusted R2 = 0.64; 70 treatment groups). Type of husbandry had a significant effect on maintenance energy requirements (P<0.001): requirements were greatest in racing dogs, followed by working dogs and hunting dogs, whilst the energy requirements of pet dogs and kennel dogs were least. Maintenance energy requirements were less in neutered compared with sexually intact dogs (P<0.001), but there was no effect of sex. Further, reported activity level tended to effect the maintenance energy requirement of the dog (P = 0.09). This review suggests that estimating maintenance energy requirements based on BW alone may not be accurate, but that predictions that factor in husbandry, neuter status and, possibly, activity level might be superior. Additionally, more information on the nutrient requirements of older dogs, and those at the extremes of body size (i.e. giant and toy breeds) is needed.
Energy Requirements of Adult Dogs: A Meta-Analysis
Bermingham, Emma N.; Thomas, David G.; Cave, Nicholas J.; Morris, Penelope J.; Butterwick, Richard F.; German, Alexander J.
2014-01-01
A meta-analysis was conducted to determine the maintenance energy requirements of adult dogs. Suitable publications were first identified, and then used to generate relationships amongst energy requirements, husbandry, activity level, methodology, sex, neuter status, dog size, and age in healthy adult dogs. Allometric equations for maintenance energy requirements were determined using log-log linear regression. So that the resulting equations could readily be compared with equations reported by the National Research Council, maintenance energy requirements in the current study were determined in kcal/kg0.75 body weight (BW). Ultimately, the data of 70 treatment groups from 29 publications were used, and mean (± standard deviation) maintenance energy requirements were 142.8±55.3 kcal.kgBW−0.75.day−1. The corresponding allometric equation was 81.5 kcal.kgBW−0.93.day−1 (adjusted R2 = 0.64; 70 treatment groups). Type of husbandry had a significant effect on maintenance energy requirements (P<0.001): requirements were greatest in racing dogs, followed by working dogs and hunting dogs, whilst the energy requirements of pet dogs and kennel dogs were least. Maintenance energy requirements were less in neutered compared with sexually intact dogs (P<0.001), but there was no effect of sex. Further, reported activity level tended to effect the maintenance energy requirement of the dog (P = 0.09). This review suggests that estimating maintenance energy requirements based on BW alone may not be accurate, but that predictions that factor in husbandry, neuter status and, possibly, activity level might be superior. Additionally, more information on the nutrient requirements of older dogs, and those at the extremes of body size (i.e. giant and toy breeds) is needed. PMID:25313818
ERIC Educational Resources Information Center
Nash, J. Thomas
1983-01-01
Trends in and factors related to the nuclear industry and nuclear fuel production are discussed. Topics addressed include nuclear reactors, survival of the U.S. uranium industry, production costs, budget cuts by the Department of Energy and U.S. Geological survey for resource studies, mining, and research/development activities. (JN)
Montiel, F; Ahuja, C
2005-01-01
Prolonged postpartum anestrus is a main factor limiting reproductive efficiency in cattle, particularly in Bos indicus and Bos taurus/Bos indicus cows from tropical regions, because it prevents achievement of a 12 month calving interval. During anestrus, ovulation does not occur despite ovarian follicular development, because growing follicles do not mature. Although many factors affect postpartum anestrus, nutrition and suckling are the major factors influencing the resumption of postpartum ovarian cycles, as they affect hypothalamic, pituitary and ovarian activity and thus inhibit follicular development. Under-nutrition contributes to prolonged postpartum anestrus, particularly among cows dependent upon forages to meet their feed requirements and it apparently interacts with genetic, environmental or management factors to influence the duration of anestrus. The nutritional status or balance of an animal is evaluated through body condition score (BCS), as it reflects the body energy reserves available for metabolism, growth, lactation and activity. There is a converse relationship between energy balance and time to resumption of postpartum ovarian activity; inadequate nutrient intake results in loss of weight and BCS and finally cessation of estrous cycles. Suckling interferes with hypothalamic release of GnRH, provoking a marked suppression in pulsatile LH release, resulting in extended postpartum anestrus. The effects of suckling on regulation of tonic LH release are determined by the ability of the cow to identify a calf as her own or as unrelated. Vision and olfaction play critical roles in the development of the maternal-offspring bond, allowing the cow to identify her own calf, and abolition of both senses attenuates the negative effects of suckling on LH secretion. Thus, the maternal-offspring bond is essential for prolonged postpartum suckling-induced anovulation, and the suppressive influence of suckling is independent of neurosensory pathways within the teat or udder.
Chang, Shou-Yi; Li, Chen-En; Huang, Yi-Chung; Hsu, Hsun-Feng; Yeh, Jien-Wei; Lin, Su-Jien
2014-01-01
We report multi-component high-entropy materials as extraordinarily robust diffusion barriers and clarify the highly suppressed interdiffusion kinetics in the multi-component materials from structural and thermodynamic perspectives. The failures of six alloy barriers with different numbers of elements, from unitary Ti to senary TiTaCrZrAlRu, against the interdiffusion of Cu and Si were characterized, and experimental results indicated that, with more elements incorporated, the failure temperature of the barriers increased from 550 to 900°C. The activation energy of Cu diffusion through the alloy barriers was determined to increase from 110 to 163 kJ/mole. Mechanistic analyses suggest that, structurally, severe lattice distortion strains and a high packing density caused by different atom sizes, and, thermodynamically, a strengthened cohesion provide a total increase of 55 kJ/mole in the activation energy of substitutional Cu diffusion, and are believed to be the dominant factors of suppressed interdiffusion kinetics through the multi-component barrier materials. PMID:24561911
Activating Transcription Factor 3 Regulates Immune and Metabolic Homeostasis
Rynes, Jan; Donohoe, Colin D.; Frommolt, Peter; Brodesser, Susanne; Jindra, Marek
2012-01-01
Integration of metabolic and immune responses during animal development ensures energy balance, permitting both growth and defense. Disturbed homeostasis causes organ failure, growth retardation, and metabolic disorders. Here, we show that the Drosophila melanogaster activating transcription factor 3 (Atf3) safeguards metabolic and immune system homeostasis. Loss of Atf3 results in chronic inflammation and starvation responses mounted primarily by the larval gut epithelium, while the fat body suffers lipid overload, causing energy imbalance and death. Hyperactive proinflammatory and stress signaling through NF-κB/Relish, Jun N-terminal kinase, and FOXO in atf3 mutants deregulates genes important for immune defense, digestion, and lipid metabolism. Reducing the dose of either FOXO or Relish normalizes both lipid metabolism and gene expression in atf3 mutants. The function of Atf3 is conserved, as human ATF3 averts some of the Drosophila mutant phenotypes, improving their survival. The single Drosophila Atf3 may incorporate the diversified roles of two related mammalian proteins. PMID:22851689
NASA Astrophysics Data System (ADS)
Howard, R. G.
The active solar energy system for a recreation hall for senior citizens in Wisconsin, is equipped with 1290 square feet of evacuated tube collectors, 3000 gallons of water in a tank, and a natural gas fired furnace for auxiliary space heating and a natural gas fired domestic water heater. The solar fraction, solar savings ratio, conventional fuel savings, system performance factor, and solar system coefficient of performance are given as well as performance data for the collector, storage, domestic hot water, and space heating subsystems, operating energy, energy savings, and weather conditions. Predicted performance data are also given for comparison with the measured data.
Energy Savings Potential and RD&D Opportunities for Commercial Building HVAC Systems
DOE Office of Scientific and Technical Information (OSTI.GOV)
Goetzler, William; Shandross, Richard; Young, Jim
The Building Technologies Office (BTO) commissioned this characterization and technology assessment of heating, ventilation, and air-conditioning (HVAC) systems for commercial buildings. The main objectives of this study: Identify a wide range of technology options in varying stages of development that could reduce commercial HVAC energy consumption; Characterize these technology options based on their technical energy-savings potential, development status, non-energy benefits, and other factors affecting end-user acceptance and the ability to compete with conventional HVAC technologies; Make specific recommendations to DOE and other stakeholders on potential research, development, and demonstration (RD&D) activities that would support further development of the most promisingmore » technology options.« less
Bērziņš, Agris; Actiņš, Andris
2014-06-01
The dehydration kinetics of mildronate dihydrate [3-(1,1,1-trimethylhydrazin-1-ium-2-yl)propionate dihydrate] was analyzed in isothermal and nonisothermal modes. The particle size, sample preparation and storage, sample weight, nitrogen flow rate, relative humidity, and sample history were varied in order to evaluate the effect of these factors and to more accurately interpret the data obtained from such analysis. It was determined that comparable kinetic parameters can be obtained in both isothermal and nonisothermal mode. However, dehydration activation energy values obtained in nonisothermal mode showed variation with conversion degree because of different rate-limiting step energy at higher temperature. Moreover, carrying out experiments in this mode required consideration of additional experimental complications. Our study of the different sample and experimental factor effect revealed information about changes of the dehydration rate-limiting step energy, variable contribution from different rate limiting steps, as well as clarified the dehydration mechanism. Procedures for convenient and fast determination of dehydration kinetic parameters were offered. © 2014 Wiley Periodicals, Inc. and the American Pharmacists Association.
Sintering in Ceramics and Solid Oxide Fuel Cells
NASA Astrophysics Data System (ADS)
Hunt, Clay Dale
Nature's propensity to minimize energy, and the change in energy with respect to position, drives diffusion. Diffusion is a means by which mass transport resulting in the bonding of the particles of a powder compact can be achieved without melting. This phenomenon occurs in powdered materials near their melting temperature, and is referred to as "sintering". Because of the extreme melting temperature of some materials, sintering might be the only practical means of processing. The complexity and subtlety of sintering ceramics motivated the evaluation of empirical data and existing sintering models. This project examined polycrystalline cubic-zirconia sintering with and without transition-metal oxide additions that change sintering behavior. This study was undertaken to determine how sintering aids affect the driving force, and activation energy, the energy barrier that must be overcome in order for an atom or ion to diffuse, of the densification occurring during sintering. Examination of commercially-available cubic-zirconia powder sintering behavior was undertaken with dilatometry, which allows monitoring of the length change a material undergoes as it sinters, and with scanning electron microscopy, which facilitates the study of sintered-sample microstructure. MATLAB algorithms quantifying sintering results were developed. Results from this work include proposed definitions of a 26-year-old undefined function of density factor in a well-accepted mathematical model of sintering. These findings suggest activation energy is not changing with density, as is suggested by recent published results. The first numerical integration of the studied sintering model has been performed. With these tools, a measure of the activation energy of densification of cubic-zirconia with and without the addition of cobalt-oxide as a sintering aid has been performed. The resulting MATLAB algorithms can be used in future sintering studies. It is concluded that sintering enhancement achieved with cobalt-oxide addition comes from reduction in activation energy of densification of cubic-zirconia. Further, it is suggested that the activation energy of densification does not change with material density. This conclusion is supported by the sensitivity of the numerical integration of the aforementioned sintering model to changes in activation energy.
Analysis of temperature difference on the total of energy expenditure during static bicycle exercise
NASA Astrophysics Data System (ADS)
Sugiono
2016-04-01
How to manage energy expenditure for cyclist is very crucial part to achieve a good performance. As the tropical situation, the differences of temperature level might be contributed in energy expenditure and durability. The aim of the paper is to estimate and to analysis the configuration of energy expenditure for static cycling activity based on heart rate value in room with air conditioning (AC)/no AC treatment. The research is started with study literatures of climate factors, temperature impact on human body, and definition of energy expenditure. The next step is design the experiment for 5 participants in 2 difference models for 26.80C - 74% relative humidity (room no AC) and 23,80C - 54.8% relative humidity (room with AC). The participants’ heart rate and blood pressure are measured in rest condition and in cycling condition to know the impact of difference temperature in energy expenditure profile. According to the experiment results, the reducing of the temperature has significantly impact on the decreasing of energy expenditure at average 0.3 Kcal/minute for all 5 performers. Finally, the research shows that climate condition (temperature and relative humidity) are very important factors to manage and to reach a higher performance of cycling sport.
The anti-obesity effect of starch in a whole grain-like structural form.
Luo, Kaiyun; Wang, Xufeng; Zhang, Genyi
2018-06-13
Obesity is a risk factor for many chronic diseases, and the anti-obesity effect of starch in a whole grain-like structural form (WGLSF) prepared through co-gelation with oat β-glucan and alginate was studied using high-fat (HF) induced obese male C57BL/6J mice. In vitro human fecal fermentation of WGLSF-starch showed a slower rate of fermentation and a higher production of butyric acid (132.0 μmol per 50 mg sample) when compared to the physical mixture counterpart of starch, β-glucan, and alginate (PM) (110.5 μmol per 50 mg) or β-glucan itself (96.2 μmol per 50 mg). The body weight gain of obese mice fed with a HF-WGLSF diet was significantly reduced (42.0% lower than the HF group, 30.2% lower than the physical mixture) with decreased cell size in white adipose tissue and similar levels of serum lipid profiles to the control of the low-fat (LF) group. Western blotting experiments showed the down-regulated lipogenic transcription factor of SREBP-1c and fatty acid synthase (FAS), but the lipid-oxidation related transcription factors of peroxisome proliferator-activated receptor-α (PPAR-α) and phosphorylated AMP-activated protein kinase (p-AMPK) were up-regulated. Energy metabolism analysis revealed increased lipid-sourced energy expenditure with higher heat production and respiratory exchange ratios. Consistently, the expression of hypothalamic pro-opiomelanocortin (POMC), favoring energy expenditure, was increased significantly while the neuropeptide Y (NPY) was reduced. Thus, the increased energy expenditure stimulated by starch in a whole-grain-like structural form is responsible for the reduced body weight gain of obese mice fed with a high fat-based diet.
Modelling oxygen transfer using dynamic alpha factors.
Jiang, Lu-Man; Garrido-Baserba, Manel; Nolasco, Daniel; Al-Omari, Ahmed; DeClippeleir, Haydee; Murthy, Sudhir; Rosso, Diego
2017-11-01
Due to the importance of wastewater aeration in meeting treatment requirements and due to its elevated energy intensity, it is important to describe the real nature of an aeration system to improve design and specification, performance prediction, energy consumption, and process sustainability. Because organic loadings drive aeration efficiency to its lowest value when the oxygen demand (energy) is the highest, the implications of considering their dynamic nature on energy costs are of utmost importance. A dynamic model aimed at identifying conservation opportunities is presented. The model developed describes the correlation between the COD concentration and the α factor in activated sludge. Using the proposed model, the aeration efficiency is calculated as a function of the organic loading (i.e. COD). This results in predictions of oxygen transfer values that are more realistic than the traditional method of assuming constant α values. The model was applied to two water resource recovery facilities, and was calibrated and validated with time-sensitive databases. Our improved aeration model structure increases the quality of prediction of field data through the recognition of the dynamic nature of the alpha factor (α) as a function of the applied oxygen demand. For the cases presented herein, the model prediction of airflow improved by 20-35% when dynamic α is used. The proposed model offers a quantitative tool for the prediction of energy demand and for minimizing aeration design uncertainty. Copyright © 2017 Elsevier Ltd. All rights reserved.
Wang, Ping; Lu, Zhengnan; Sun, Jihong
2018-01-01
Background: New energy has become a key trend for global energy industry development. Talent plays a very critical role in the enhancement of new energy enterprise competitiveness. As a key component of talent, managers have been attracting more and more attention. The increase in job performance relies on, to a certain extent, incentive mechanism. Based on the Two-factor Theory, differences in influences and effects of different incentives on management performance have been checked in this paper from an empirical perspective. Methods: This paper selects the middle and low level managers in new energy enterprises as research samples and classifies the managers’ performance into task performance, contextual performance and innovation performance. It uses manager performance questionnaires and intrinsic-extrinsic incentive factor questionnaires to investigate and study the effects and then uses Amos software to analyze the inner link between the intrinsic-extrinsic incentives and job performance. Results: Extrinsic incentives affect task performance and innovation performance positively. Intrinsic incentives impose active significant effects on task performance, contextual performance, and innovation performance. The intrinsic incentive plays a more important role than the extrinsic incentive. Conclusions: Both the intrinsic-extrinsic incentives affect manager performance positively and the intrinsic incentive plays a more important role than the extrinsic incentive. Several suggestions to management should be given based on these results. PMID:29419730
Microbiological Transformations of Radionuclides in the Subsurface
DOE Office of Scientific and Technical Information (OSTI.GOV)
Marshall, Matthew J.; Beliaev, Alex S.; Fredrickson, Jim K.
2010-01-04
Microorganisms are ubiquitous in subsurface environments although their populations sizes and metabolic activities can vary considerably depending on energy and nutrient inputs. As a result of their metabolic activities and the chemical properties of their cell surfaces and the exopolymers they produce, microorganisms can directly or indirectly facilitate the biotransformation of radionuclides, thus altering their solubility and overall fate and transport in the environment. Although biosorption to cell surfaces and exopolymers can be an important factor modifying the solubility of some radionuclides under specific conditions, oxidation state is often considered the single most important factor controlling their speciation and, therefore,more » environmental behavior.« less
Increasing the energy conservation awareness using the influential power of a lottery system
NASA Astrophysics Data System (ADS)
Nayak, Amruta Vijay
This thesis presents an influence maximization-driven approach to promoting energy conservation awareness, with the objective to generate a competitive environment for energy consumption supervision. As consumers are typically reluctant to invest their time and effort in the activities beyond their business, an incentive-based distribution strategy is proposed to encourage consumers to actively take part in energy conservation. The key idea of the thesis lies in leveraging the consumer instincts as a driving factor for spreading positive social influence, via a smart lottery program. In the proposed framework, saving energy automatically increases the consumers' chances of winning the lottery, thereby motivating them to save more, while the smart winner selection will maximize the word-of-mouth effect of the program. The thesis collects and organizes a large body of literature in support of the claim that the spread of awareness in a social network can play a key role in the emergence of energy conscious behavior. It also reports on the findings of a survey conducted to determine the present day consumer perspective toward energy conservation and the level of influence required to motivate them to conserve more energy. Finally, a mathematical model for smart lottery winner selection is presented, and insightful observations are made concerning the properties of optimal solutions to tractable, small problem instances.
Verhoeven, Katrien; Abeele, Vero Vanden; Gers, Brent; Seghers, Jan
2015-12-01
There has been growing interest in the use of active videogames to influence levels of physical activity. Most studies have investigated energy expenditure in general, without taking into account moderating factors such as player mode and game enjoyment. This study therefore examines whether children's energy expenditure and game enjoyment are higher when games are played in a two-player mode than in a single-player mode. Forty-three children from the 7th grade who exhibited an inactive lifestyle engaged in six sports exergames on an Xbox(®) Kinect(®) (Microsoft, Redmond, WA) console. The player mode (single-player or two-player mode) was manipulated (within-subjects design). The primary parameters were "energy expenditure," which was measured with a SenseWear(®) device (Bodymedia Inc., Pittsburgh, PA), and "game enjoyment," which was assessed through self-report. On average, Kinect play elicits moderate physical activity (approximately 4 metabolic equivalents of task). Games that are played in a two-player mode elicit more energy than games that are played in a single-player mode. However, this was only the case for simultaneous play (boxing, dancing, and tennis), not for turn-based play (bowling, baseball, and golf). Furthermore, participants generally liked exergaming, regardless of their sex or the player mode. Finally, no significant correlation was found between energy expenditure and game enjoyment. This study has shown that Kinect play elicits physical activity of moderate intensity. Furthermore, Kinect play is generally enjoyed by both boys and girls. Simultaneous play may be the best suited to increase levels of physical activity in early adolescents who exhibit an inactive lifestyle.
Ramos, J L; Guerrero, M G; Losada, M
1987-04-01
Synthesis of ammonia from dinitrogen and water by suspensions of Anabaena sp. Strain ATCC 33047 treated with the glutamine synthetase inhibitor L-methionine-D,L-sulfoximine is strictly dependent on light. Under otherwise optimal conditions, the yield of ammonia production is influenced by irradiance, as well as by the density, depth, and turbulence of the cell suspension. The interaction among these factors seems to determine the actual amount of light available to each single cell or filament in the suspension for the photoproduction process. Under convenient illumination, the limiting factor in the synthesis of ammonia seems to be the cellular nitrogenase activity level, but under limiting light conditions the limiting factor could, however, be the assimilatory power required for nitrogen fixation. Photosynthetic ammonia production from atmospheric nitrogen and water can operate with an efficiency of ca. 10% of its theoretical maximum, representing a remarkable process for the conversion of light energy into chemical energy.
Pavankumar, Asalapuram R; Kayathri, Rajarathinam; Murugan, Natarajan A; Zhang, Qiong; Srivastava, Vaibhav; Okoli, Chuka; Bulone, Vincent; Rajarao, Gunaratna K; Ågren, Hans
2014-01-01
Many proteins exist in dimeric and other oligomeric forms to gain stability and functional advantages. In this study, the dimerization property of a coagulant protein (MO2.1) from Moringa oleifera seeds was addressed through laboratory experiments, protein-protein docking studies and binding free energy calculations. The structure of MO2.1 was predicted by homology modelling, while binding free energy and residues-distance profile analyses provided insight into the energetics and structural factors for dimer formation. Since the coagulation activities of the monomeric and dimeric forms of MO2.1 were comparable, it was concluded that oligomerization does not affect the biological activity of the protein.
Is it worth expending energy to convert biliverdin into bilirubin?
Nam, Joon; Lee, Yonghyun; Yang, Yejin; Jeong, Seongkeun; Kim, Wooseong; Yoo, Jin-Wook; Moon, Jeon-Ok; Lee, Changyong; Chung, Hae Young; Kim, Min-Soo; Jon, Sangyong; Jung, Yunjin
2018-06-10
Bilirubin (BR) is generated by the reduction of biliverdin (BV), a metabolite that results from the catalytic degradation of heme by the isoforms of heme oxygenase (HO). BV is nontoxic and water-soluble but BR is potentially toxic and lipophilic. Therefore, a further metabolic step is required for BR before excretion is possible. The reductive conversion of BV to BR costs energy and is evolutionarily conserved in human physiology. There must be a compelling reason for this apparently nonsensical evolutionary conservation. In addition to the differences between BR and BV-such as water solubility, antioxidant activity, and participation as a receptor ligand-in the present study, we focused on the chemistry of the two metabolites with regard to an electrophilic functional group called a Michael reaction acceptor (MRA). Our data reveal that the BR reacts with thiol compounds forming adducts, whereas no reaction occurs with BV. Furthermore, the binding of biotin-tagged BR to Kelch-like ECH-associated protein 1 (KEAP1)-a biological electrophile sensor-was prevented by pretreatment with BR or a thiol compound, but was not by pretreatment with BV. In cells, BR could bind to KEAP1 to release and activate nuclear factor-erythroid 2 (NF-E2) p45-related factor 2, a cytoprotective transcription factor, leading to the induction of HO-1. These findings may provide a physiological rationale for the energy-consuming conversion of BV to BR. Copyright © 2018. Published by Elsevier Inc.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gagne, F.; Burgeot, T.; Hellou, J.
2008-06-15
Economic and social developments have taken place at the expense of the health of the environment, both locally and on a global scale. In an attempt to better understand the large-scale effects of pollution and other stressors like climate change on the health status of Mytilus edulis, mussels were collected during the first two weeks of June 2005 at three sites (one pristine and two affected by pollution) located in each of the regions of the Canadian West Coast, the St. Lawrence estuary, the Atlantic East Coast and the northwestern coast of France, covering a total distance of some 11more » 000 km. The mussels were analyzed for morphologic integrity (condition factor), gametogenic activity (gonado-somatic and gonad maturation index, vitellogenin(Vtg)-like proteins), energy status (temperature-dependent mitochondrial electron transport activity and gonad lipid stores), defense mechanisms (glutathione S-transferase, metallothioneins, cytochrome P4503A activity and xanthine oxidoreductase-XOR), and tissue damage (lipid peroxidation-LPO and DNA strand breaks). The results showed that data from the reference sites in each region were usually not normally distributed, with discriminant factors reaching the number of regions (i.e. four), except for the biomarkers gonadal lipids, XOR and LPO in digestive gland. The integrated responses of the biomarkers revealed that biomarkers of stress were significantly more pronounced in mussels from the Seine estuary, suggesting that the impacts of pollution are more generalized in this area. Mussels from the Seine estuary and the Atlantic East Coast (Halifax Harbor) responded more strongly for Vtg-like proteins, but was not related to gonad maturation and gonado-somatic indexes, suggesting the presence of environmental estrogens. Moreover, these mussels displayed reduced DNA repair activity and increased LPO. Factorial analyses revealed that energy status, cytochrome P4503A activity and Vtg-like proteins were the most important biomarkers. Adaptation to warmer temperatures was reflected at the energy status levels, mussels from both the polluted and warmer sites displaying increased ratios of mitochondrial activity to lipid stores. Regional observations of biomarkers of energy status, gametogenesis and pollutant-related effects were influenced by nutrition, oxygen availability (eutrophication), and thermal history.« less
Myostatin regulates energy homeostasis in the heart and prevents heart failure.
Biesemann, Nadine; Mendler, Luca; Wietelmann, Astrid; Hermann, Sven; Schäfers, Michael; Krüger, Marcus; Boettger, Thomas; Borchardt, Thilo; Braun, Thomas
2014-07-07
Myostatin is a major negative regulator of skeletal muscle mass and initiates multiple metabolic changes, including enhanced insulin sensitivity. However, the function of myostatin in the heart is barely understood, although it is upregulated in the myocardium under several pathological conditions. Here, we aimed to decipher the role of myostatin and myostatin-dependent signaling pathways for cardiac function and cardiac metabolism in adult mice. To avoid potential counterregulatory mechanisms occurring in constitutive and germ-line-based myostatin mutants, we generated a mouse model that allows myostatin inactivation in adult cardiomyocytes. Cardiac MRI revealed that genetic inactivation of myostatin signaling in the adult murine heart caused cardiac hypertrophy and heart failure, partially recapitulating effects of the age-dependent decline of the myostatin paralog growth and differentiation factor 11. We found that myostatin represses AMP-activated kinase activation in the heart via transforming growth factor-β-activated kinase 1, thereby preventing a metabolic switch toward glycolysis and glycogen accumulation. Furthermore, myostatin stimulated expression of regulator of G-protein signaling 2, a GTPase-activating protein that restricts Gaq and Gas signaling and thereby protects against cardiac failure. Inhibition of AMP-activated kinase in vivo rescued cardiac hypertrophy and prevented enhanced glycolytic flow and glycogen accumulation after inactivation of myostatin in cardiomyocytes. Our results uncover an important role of myostatin in the heart for maintaining cardiac energy homeostasis and preventing cardiac hypertrophy. © 2014 American Heart Association, Inc.
Human Protein Kinases and Obesity.
Engin, Atilla
2017-01-01
The action of protein kinases and protein phosphatases is essential for multiple physiological responses. Each protein kinase displays its own unique substrate specificity, and a regulatory mechanism that may be modulated by association with other proteins. Protein kinases are classified by the target amino acid in their substrates. Some protein kinases can phosphorylate both serine/threonine, as well as tyrosine residues. This group of kinases has been known as dual specificity kinases. Unlike the dual specificity kinases, a heterogeneous group of protein phosphatases are known as dual-specificity phosphatases. These phosphatases remove phosphate groups from tyrosine and serine/threonine residues on their substrate. Dual-specificity phosphatases are important signal transduction enzymes that regulate various cellular processes in coordination with protein kinases. The protein kinase-phosphoproteins interactions play an important role in obesity . In obesity, the pro- and anti-inflammatory effects of adipokines and cytokines through intracellular signaling pathways mainly involve the nuclear factor kappa B (NF-kappaB) and the c-Jun N-terminal kinase (JNK) systems as well as the inhibitor of kappaB-kinase beta (IKK beta). Impairment of insulin signaling in obesity is largely mediated by the activation of the IKKbeta and the JNK. Furthermore, oxidative stress and endoplasmic reticulum (ER) stress activate the JNK pathway which suppresses insulin biosynthesis. Additionally, obesity-activated calcium/calmodulin dependent-protein kinase II/p38 suppresses insulin-induced protein kinase B phosphorylation by activating the ER stress effector, activating transcription factor-4. Obese adults with vascular endothelial dysfunction have greater endothelial cells activation of unfolded protein response stress sensors, RNA-dependent protein kinase-like ER eukaryotic initiation factor-2alpha kinase (PERK) and activating transcription factor-6. The transcriptional regulation of adipogenesis in obesity is influenced by AGC (protein kinase A (PKA), PKG, PKC) family signaling kinases. Obesity may induce systemic oxidative stress and increase reactive oxygen species in adipocytes. Increase in intracellular oxidative stress can promote PKC-beta activation. Activated PKC-beta induces growth factor adapter Shc phosphorylation. Shc-generated peroxides reduce mitochondrial oxygen consumption and enhances triglyceride accumulation. Obesity is fundamentally caused by cellular energy imbalance and dysregulation. Like adenosine monophosphate (AMP)-activated protein kinase (AMPK) and mammalian target of rapamycin (mTOR), N-terminal Per-ARNT-Sim (PAS) kinase are nutrient responsive protein kinases and important for proper regulation of glucose metabolism in mammals at both the hormonal and cellular level. Defective responses of AMPK to leptin may contribute to resistance to leptin action on food intake and energy expenditure in obese states.
A density functional theory model of mechanically activated silyl ester hydrolysis
DOE Office of Scientific and Technical Information (OSTI.GOV)
Pill, Michael F.; Schmidt, Sebastian W.; Institut für Physikalische Chemie, Christian-Albrechts-Universität zu Kiel, Olshausenstraße 40, 24098 Kiel
2014-01-28
To elucidate the mechanism of the mechanically activated dissociation of chemical bonds between carboxymethylated amylose (CMA) and silane functionalized silicon dioxide, we have investigated the dissociation kinetics of the bonds connecting CMA to silicon oxide surfaces with density functional calculations including the effects of force, solvent polarizability, and pH. We have determined the activation energies, the pre-exponential factors, and the reaction rate constants of candidate reactions. The weakest bond was found to be the silyl ester bond between the silicon and the alkoxy oxygen atom. Under acidic conditions, spontaneous proton addition occurs close to the silyl ester such that neutralmore » reactions become insignificant. Upon proton addition at the most favored position, the activation energy for bond hydrolysis becomes 31 kJ mol{sup −1}, which agrees very well with experimental observation. Heterolytic bond scission in the protonated molecule has a much higher activation energy. The experimentally observed bi-exponential rupture kinetics can be explained by different side groups attached to the silicon atom of the silyl ester. The fact that different side groups lead to different dissociation kinetics provides an opportunity to deliberately modify and tune the kinetic parameters of mechanically activated bond dissociation of silyl esters.« less
Children and young people’s perceptions of energy drinks: A qualitative study
2017-01-01
Background Consumption of soft drinks is declining in many countries, yet energy drink sales continue to increase, particularly amongst young consumers. Little is currently known about the drivers behind these trends. Energy drinks are high in sugar and caffeine, and evidence indicates that regular or heavy use by under 18s is likely to be detrimental to health. This study aimed to explore children and young people’s attitudes and perceptions in relation to energy drinks in a UK context. Methods Eight focus groups were conducted with pupils aged 10–11 years (n = 20) and 13–14 years (n = 17) from four schools in northern England. A sub-sample also took part in a mapping exercise to generate further insights. Data were analysed using the constant comparative approach. Results Energy drinks were reportedly consumed in a variety of public and private places, generally linked to social activities, sports and computer gaming (particularly amongst boys). Participants demonstrated strong brand awareness and preferences that were linked to taste and perceived value for money. The relatively low price of energy drinks and their widespread availability were identified as key factors, along with gendered branding and marketing. Some participants demonstrated a critical approach to manufacturers’ claims and many were keen to become better informed, often through school- or peer-based interventions. Other potential interventions included age restrictions, voluntary schemes involving retailers and improved labelling. Conclusions The lack of a single dominant factor in participants’ consumption choices suggests that there is unlikely to be a ‘silver bullet’ in attempting to address this issue. However, the findings provide support for policy-level interventions that seek to change the behaviours of manufacturers and retailers as well as consumers, and actively involve children and young people where possible. PMID:29190753
Children and young people's perceptions of energy drinks: A qualitative study.
Visram, Shelina; Crossley, Stephen J; Cheetham, Mandy; Lake, Amelia
2017-01-01
Consumption of soft drinks is declining in many countries, yet energy drink sales continue to increase, particularly amongst young consumers. Little is currently known about the drivers behind these trends. Energy drinks are high in sugar and caffeine, and evidence indicates that regular or heavy use by under 18s is likely to be detrimental to health. This study aimed to explore children and young people's attitudes and perceptions in relation to energy drinks in a UK context. Eight focus groups were conducted with pupils aged 10-11 years (n = 20) and 13-14 years (n = 17) from four schools in northern England. A sub-sample also took part in a mapping exercise to generate further insights. Data were analysed using the constant comparative approach. Energy drinks were reportedly consumed in a variety of public and private places, generally linked to social activities, sports and computer gaming (particularly amongst boys). Participants demonstrated strong brand awareness and preferences that were linked to taste and perceived value for money. The relatively low price of energy drinks and their widespread availability were identified as key factors, along with gendered branding and marketing. Some participants demonstrated a critical approach to manufacturers' claims and many were keen to become better informed, often through school- or peer-based interventions. Other potential interventions included age restrictions, voluntary schemes involving retailers and improved labelling. The lack of a single dominant factor in participants' consumption choices suggests that there is unlikely to be a 'silver bullet' in attempting to address this issue. However, the findings provide support for policy-level interventions that seek to change the behaviours of manufacturers and retailers as well as consumers, and actively involve children and young people where possible.
Savory, L A; Griffin, S J; Williams, K M; Prevost, A T; Kinmonth, A-L; Wareham, N J; Simmons, R K
2014-02-01
To describe change in self-reported diet and plasma vitamin C, and to examine associations between change in diet and cardiovascular disease risk factors and modelled 10-year cardiovascular disease risk in the year following diagnosis of Type 2 diabetes. Eight hundred and sixty-seven individuals with screen-detected diabetes underwent assessment of self-reported diet, plasma vitamin C, cardiovascular disease risk factors and modelled cardiovascular disease risk at baseline and 1 year (n = 736) in the ADDITION-Cambridge trial. Multivariable linear regression was used to quantify the association between change in diet and cardiovascular disease risk at 1 year, adjusting for change in physical activity and cardio-protective medication. Participants reported significant reductions in energy, fat and sodium intake, and increases in fruit, vegetable and fibre intake over 1 year. The reduction in energy was equivalent to an average-sized chocolate bar; the increase in fruit was equal to one plum per day. There was a small increase in plasma vitamin C levels. Increases in fruit intake and plasma vitamin C were associated with small reductions in anthropometric and metabolic risk factors. Increased vegetable intake was associated with an increase in BMI and waist circumference. Reductions in fat, energy and sodium intake were associated with reduction in HbA1c , waist circumference and total cholesterol/modelled cardiovascular disease risk, respectively. Improvements in dietary behaviour in this screen-detected population were associated with small reductions in cardiovascular disease risk, independently of change in cardio-protective medication and physical activity. Dietary change may have a role to play in the reduction of cardiovascular disease risk following diagnosis of diabetes. © 2013 The Authors. Diabetic Medicine published by John Wiley & Sons Ltd on behalf of Diabetes UK.
Mongolia's potential in international cooperation in the Asian energy space
NASA Astrophysics Data System (ADS)
Batmunkh, Sereeter; Stennikov, Valery; Bat-Erdene, Bayar; Erdenebaatar, Altay
2018-01-01
The paper is concerned with the issues of interstate electric power interconnections to be created in the countries of Northeast Asia. The conditions are formulated, the problems are stated, and solutions for Mongolia's entry into the Asian energy space are proposed. The electricity consumption rates are growing, however, the Northeast Asia countries differ considerably in available energy resources to cope with this growth. Therefore, the need to build international electric power interconnections that take into account climatic features, seasonal peak load differences and other factors in order to rationally match power demand and supply is getting increasingly more obvious. Mongolia can take an active part in this process, as the country is rich in energy resources and interested in their development to meet their domestic needs and exchange with neighboring countries. The establishment of interstate power interconnections in the Northeast Asia countries represents a topical task whose solution will make it possible to meet the demand of this region for electricity on mutually beneficial terms. Mongolia has a good spatial position, energy resources and is interested in ensuring domestic energy balance. Therefore, the country can be an active participant in such an integration process.
Planning building energy conservation research in the US
DOE Office of Scientific and Technical Information (OSTI.GOV)
Abel, F.; LaMontagne, J.
1988-01-01
In the US, the federal government plays a key role in the development of energy conserving technologies and practices for buildings. The Office of Buildings and Community Systems (BCS) of the US Department of Energy provides federal leadership for both private and public sector activities in building energy conservation. The federal role in recent years has been largely limited to the development of technical options; behavioral and institutional factors are considered only to the extent necessary to inform the research planning process. Planning in the US requires dealing with uncertainties regarding the federal approach to energy conservation; this can change,more » often dramatically, with changes in administrations or changing economic and energy conditions. Thus federal research plans must be designed to be useful in a wide variety of circumstances. 7 refs.« less
Collu-Marchese, Melania; Shuen, Michael; Pauly, Marion; Saleem, Ayesha; Hood, David A
2015-05-19
The ATP demand required for muscle development is accommodated by elevations in mitochondrial biogenesis, through the co-ordinated activities of the nuclear and mitochondrial genomes. The most important transcriptional activator of the mitochondrial genome is mitochondrial transcription factor A (Tfam); however, the regulation of Tfam expression during muscle differentiation is not known. Thus, we measured Tfam mRNA levels, mRNA stability, protein expression and localization and Tfam transcription during the progression of muscle differentiation. Parallel 2-fold increases in Tfam protein and mRNA were observed, corresponding with 2-3-fold increases in mitochondrial content. Transcriptional activity of a 2051 bp promoter increased during this differentiation period and this was accompanied by a 3-fold greater Tfam mRNA stabilization. Interestingly, truncations of the promoter at 1706 bp, 978 bp and 393 bp promoter all exhibited 2-3-fold higher transcriptional activity than the 2051 bp construct, indicating the presence of negative regulatory elements within the distal 350 bp of the promoter. Activation of AMP kinase augmented Tfam transcription within the proximal promoter, suggesting the presence of binding sites for transcription factors that are responsive to cellular energy state. During differentiation, the accumulating Tfam protein was progressively distributed to the mitochondrial matrix where it augmented the expression of mtDNA and COX (cytochrome c oxidase) subunit I, an mtDNA gene product. Our data suggest that, during muscle differentiation, Tfam protein levels are regulated by the availability of Tfam mRNA, which is controlled by both transcription and mRNA stability. Changes in energy state and Tfam localization also affect Tfam expression and action in differentiating myotubes. © 2015 Authors.
Dhar, Shilpa S; Liang, Huan Ling; Wong-Riley, Margaret T T
2009-10-01
Neuronal activity is highly dependent on energy metabolism; yet, the two processes have traditionally been regarded as independently regulated at the transcriptional level. Recently, we found that the same transcription factor, nuclear respiratory factor 1 (NRF-1) co-regulates an important energy-generating enzyme, cytochrome c oxidase, as well as critical subunits of glutamatergic receptors. The present study tests our hypothesis that the co-regulation extends to the next level of glutamatergic synapses, namely, neuronal nitric oxide synthase, which generates nitric oxide as a downstream signaling molecule. Using in silico analysis, electrophoretic mobility shift assay, chromatin immunoprecipitation, promoter mutations, and NRF-1 silencing, we documented that NRF-1 functionally bound to Nos1, but not Nos2 (inducible) and Nos3 (endothelial) gene promoters. Both COX and Nos1 transcripts were up-regulated by depolarizing KCl treatment and down-regulated by TTX-mediated impulse blockade in neurons. However, NRF-1 silencing blocked the up-regulation of both Nos1 and COX induced by KCl depolarization, and over-expression of NRF-1 rescued both Nos1 and COX transcripts down-regulated by TTX. These findings are consistent with our hypothesis that synaptic neuronal transmission and energy metabolism are tightly coupled at the molecular level.
Estimation of the kinetic energy dissipation in fall-arrest system and manikin during fall impact.
Wu, John Z; Powers, John R; Harris, James R; Pan, Christopher S
2011-04-01
Fall-arrest systems (FASs) have been widely applied to provide a safe stop during fall incidents for occupational activities. The mechanical interaction and kinetic energy exchange between the human body and the fall-arrest system during fall impact is one of the most important factors in FAS ergonomic design. In the current study, we developed a systematic approach to evaluate the energy dissipated in the energy absorbing lanyard (EAL) and in the harness/manikin during fall impact. The kinematics of the manikin and EAL during the impact were derived using the arrest-force time histories that were measured experimentally. We applied the proposed method to analyse the experimental data of drop tests at heights of 1.83 and 3.35 m. Our preliminary results indicate that approximately 84-92% of the kinetic energy is dissipated in the EAL system and the remainder is dissipated in the harness/manikin during fall impact. The proposed approach would be useful for the ergonomic design and performance evaluation of an FAS. STATEMENT OF RELEVANCE: Mechanical interaction, especially kinetic energy exchange, between the human body and the fall-arrest system during fall impact is one of the most important factors in the ergonomic design of a fall-arrest system. In the current study, we propose an approach to quantify the kinetic energy dissipated in the energy absorbing lanyard and in the harness/body system during fall impact.
THE INTERNAL STRUCTURE OF OVERPRESSURED, MAGNETIZED, RELATIVISTIC JETS
DOE Office of Scientific and Technical Information (OSTI.GOV)
Martí, J. M.; Perucho, M.; Gómez, J. L.
This work presents the first characterization of the internal structure of overpressured, steady superfast-magnetosonic relativistic jets in connection with their dominant type of energy. To this aim, relativistic magnetohydrodynamic simulations of different jet models threaded by a helical magnetic field have been analyzed covering a wide region in the magnetosonic Mach number–specific internal energy plane. The merit of this plane is that models dominated by different types of energy (internal energy: hot jets; rest-mass energy: kinetically dominated jets; magnetic energy: Poynting-flux-dominated jets) occupy well-separated regions. The analyzed models also cover a wide range of magnetizations. Models dominated by the internalmore » energy (i.e., hot models, or Poynting-flux-dominated jets with magnetizations larger than but close to one) have a rich internal structure characterized by a series of recollimation shocks and present the largest variations in the flow Lorentz factor (and internal energy density). Conversely, in kinetically dominated models, there is not much internal or magnetic energy to be converted into kinetic, and the jets are featureless with small variations in the flow Lorentz factor. The presence of a significant toroidal magnetic field threading the jet produces large gradients in the transversal profile of the internal energy density. Poynting-flux-dominated models with high magnetization (≈10 or larger) are prone to be unstable against magnetic pinch modes, which sets limits on the expected magnetization in parsec-scale active galactic nucleus jets or constrains their magnetic field configuration.« less
Nutritional status in chronic obstructive pulmonary disease: role of hypoxia.
Raguso, Comasia A; Luthy, Christophe
2011-02-01
In patients with chronic obstructive pulmonary disease (COPD), malnutrition and limited physical activity are very common and contribute to disease prognosis, whereas a balance between caloric intake and exercise allows body weight stability and muscle mass preservation. The goal of this review is to analyze the implications of chronic hypoxia on three key elements involved in energy homeostasis and its role in COPD cachexia. The first one is energy intake. Body weight loss, often observed in patients with COPD, is related to lack of appetite. Inflammatory cytokines are known to be involved in anorexia and to be correlated to arterial partial pressure of oxygen. Recent studies in animals have investigated the role of hypoxia in peptides involved in food consumption such as leptin, ghrelin, and adenosine monophosphate activated protein kinase. The second element is muscle function, which is strongly related to energy use. In COPD, muscle atrophy and muscle fiber shift to the glycolytic type might be an adaptation to chronic hypoxia to preserve the muscle from oxidative stress. Muscle atrophy could be the result of a marked activation of the ubiquitin-proteasome pathway as found in muscle of patients with COPD. Hypoxia, via hypoxia inducible factor-1, is implicated in mitochondrial biogenesis and autophagy. Third, hormonal control of energy balance seems to be affected in patients with COPD. Insulin resistance has been described in this group of patients as well as a sort of "growth hormone resistance." Hypoxia, by hypoxia inducible factor-1, accelerates the degradation of tri-iodothyronine and thyroxine, decreasing cellular oxygen consumption, suggesting an adaptive mechanism rather than a primary cause of COPD cachexia. COPD rehabilitation aimed at maintaining function and quality of life needs to address body weight stabilization and, in particular, muscle mass preservation. Copyright © 2011 Elsevier Inc. All rights reserved.
Generalized five-dimensional dynamic and spectral factor analysis
DOE Office of Scientific and Technical Information (OSTI.GOV)
El Fakhri, Georges; Sitek, Arkadiusz; Zimmerman, Robert E.
2006-04-15
We have generalized the spectral factor analysis and the factor analysis of dynamic sequences (FADS) in SPECT imaging to a five-dimensional general factor analysis model (5D-GFA), where the five dimensions are the three spatial dimensions, photon energy, and time. The generalized model yields a significant advantage in terms of the ratio of the number of equations to that of unknowns in the factor analysis problem in dynamic SPECT studies. We solved the 5D model using a least-squares approach. In addition to the traditional non-negativity constraints, we constrained the solution using a priori knowledge of both time and energy, assuming thatmore » primary factors (spectra) are Gaussian-shaped with full-width at half-maximum equal to gamma camera energy resolution. 5D-GFA was validated in a simultaneous pre-/post-synaptic dual isotope dynamic phantom study where {sup 99m}Tc and {sup 123}I activities were used to model early Parkinson disease studies. 5D-GFA was also applied to simultaneous perfusion/dopamine transporter (DAT) dynamic SPECT in rhesus monkeys. In the striatal phantom, 5D-GFA yielded significantly more accurate and precise estimates of both primary {sup 99m}Tc (bias=6.4%{+-}4.3%) and {sup 123}I (-1.7%{+-}6.9%) time activity curves (TAC) compared to conventional FADS (biases=15.5%{+-}10.6% in {sup 99m}Tc and 8.3%{+-}12.7% in {sup 123}I, p<0.05). Our technique was also validated in two primate dynamic dual isotope perfusion/DAT transporter studies. Biases of {sup 99m}Tc-HMPAO and {sup 123}I-DAT activity estimates with respect to estimates obtained in the presence of only one radionuclide (sequential imaging) were significantly lower with 5D-GFA (9.4%{+-}4.3% for {sup 99m}Tc-HMPAO and 8.7%{+-}4.1% for {sup 123}I-DAT) compared to biases greater than 15% for volumes of interest (VOI) over the reconstructed volumes (p<0.05). 5D-GFA is a novel and promising approach in dynamic SPECT imaging that can also be used in other modalities. It allows accurate and precise dynamic analysis while compensating for Compton scatter and cross-talk.« less
Gabe-Thomas, Elizabeth; Walker, Ian; Verplanken, Bas; Shaddick, Gavin
2016-01-01
If in-home displays and other interventions are to successfully influence people's energy consumption, they need to communicate about energy in terms that make sense to users. Here we explore householders' perceptions of energy consumption, using a novel combination of card-sorting and clustering to reveal shared patterns in the way people think about domestic energy consumption. The data suggest that, when participants were asked to group appliances which they felt naturally 'went together', there are relatively few shared ideas about which appliances are conceptually related. To the extent participants agreed on which appliances belonged together, these groupings were based on activities (e.g., entertainment) and location within the home (e.g., kitchen); energy consumption was not an important factor in people's categorisations. This suggests messages about behaviour change aimed at reducing energy consumption might better be tied to social practices than to consumption itself.
How brain response and eating habits modulate food energy estimation.
Mengotti, P; Aiello, M; Terenzi, D; Miniussi, C; Rumiati, R I
2018-05-01
The estimates we do of the energy content of different foods tend to be inaccurate, depending on several factors. The elements influencing such evaluation are related to the differences in the portion size of the foods shown, their energy density (kcal/g), but also to individual differences of the estimators, such as their body-mass index (BMI) or eating habits. Within this context the contribution of brain regions involved in food-related decisions to the energy estimation process is still poorly understood. Here, normal-weight and overweight/obese women with restrained or non-restrained eating habits, received anodal transcranial direct current stimulation (AtDCS) to modulate the activity of the left dorsolateral prefrontal cortex (dlPFC) while they performed a food energy estimation task. Participants were asked to judge the energy content of food images, unaware that all foods, for the quantity presented, shared the same energy content. Results showed that food energy density was a reliable predictor of their energy content estimates, suggesting that participants relied on their knowledge about the food energy density as a proxy for estimating food energy content. The neuromodulation of the dlPFC interacted with individual differences in restrained eating, increasing the precision of the energy content estimates in participants with higher scores in the restrained eating scale. Our study highlights the importance of eating habits, such as restrained eating, in modulating the activity of the left dlPFC during food appraisal. Copyright © 2018 Elsevier Inc. All rights reserved.
Energy metabolism, fuel selection and body weight regulation
Galgani, J; Ravussin, E
2010-01-01
Energy homeostasis is critical for the survival of species. Therefore, multiple and complex mechanisms have evolved to regulate energy intake and expenditure to maintain body weight. For weight maintenance, not only does energy intake have to match energy expenditure, but also macronutrient intake must balance macronutrient oxidation. However, this equilibrium seems to be particularly difficult to achieve in individuals with low fat oxidation, low energy expenditure, low sympathetic activity or low levels of spontaneous physical activity, as in addition to excess energy intake, all of these factors explain the tendency of some people to gain weight. Additionally, large variability in weight change is observed when energy surplus is imposed experimentally or spontaneously. Clearly, the data suggest a strong genetic influence on body weight regulation implying a normal physiology in an ‘obesogenic’ environment. In this study, we also review evidence that carbohydrate balance may represent the potential signal that regulates energy homeostasis by impacting energy intake and body weight. Because of the small storage capacity for carbohydrate and its importance for metabolism in many tissues and organs, carbohydrate balance must be maintained at a given level. This drive for balance may in turn cause increased energy intake when consuming a diet high in fat and low in carbohydrate. If sustained over time, such an increase in energy intake cannot be detected by available methods, but may cause meaningful increases in body weight. The concept of metabolic flexibility and its impact on body weight regulation is also presented. PMID:19136979
Armbrust, Wineke; Lelieveld, Otto H T M; Tuinstra, Jolanda; Wulffraat, Nico M; Bos, G J F Joyce; Cappon, Jeannette; van Rossum, Marion A J; Sauer, Pieter J J; Hagedoorn, Mariët
2016-12-06
Fatigue is common in patients with JIA and affects daily life negatively. We assessed the presence and severity of fatigue in patients with JIA, including factors presumed associated with fatigue (e.g., disease activity, disability, pain, physical activity, exercise capacity, and self-efficacy), and whether fatigue is related to participation in physical education classes, school attendance, and sports frequency. The current study used baseline data of 80 patients with JIA (age 8-13) who participated in an intervention aimed at promoting physical activity. Primary outcome measurements were fatigue, assessed using the Pediatric-Quality-of-Life-Inventory (PedsQl)-Fatigue-scale and energy level assessed using a VAS scale. Other outcome measurements were disease activity (VAS Physician Global Assessment Scale), disability (Childhood Health Assessment Questionnaire), physical activity (accelerometer), exercise capacity (Bruce treadmill test), self-efficacy (Childhood Arthritis Self-Efficacy Scale), and participation (self-report). Sixty percent of patients with JIA suffered from daily low-energy levels; 27% suffered from very low-energy levels more than half the week. Low energy levels were best predicted by disability and low physical activity. Fatigue measured with the PEDsQL was higher compared to the control-population. Disability and low self-efficacy were main predictors of fatigue. Self-efficacy was a predictor of fatigue but did not act as moderator. Fatigue was a predictor for sports frequency but not for school attendance. Fatigue is a significant problem for JIA patients. Interventions aimed at reducing perceived disability, stimulating physical activity, and enhancing self-efficacy might reduce fatigue and thereby enhance participation. Trial number ISRCTN92733069.
Evaluation of dual γ-ray imager with active collimator using various types of scintillators.
Lee, Wonho; Lee, Taewoong; Jeong, Manhee; Kim, Ho Kyung
2011-10-01
The performance of a specialized dual γ-ray imager using both mechanical and electronic collimation was evaluated by Monte Carlo simulation (MCNP5). The dual imager consisted of an active collimator and a planar detector that were made from scintillators. The active collimator served not only as a coded aperture for mechanical collimation but also as a first detector for electronic collimation. Therefore, a single system contained both mechanical and electronic collimation. Various types of scintillators were tested and compared with each other in terms of their angular resolution, efficiency, and background noise. In general, a BGO active collimator had the best mechanical collimation performance, and an LaCl₃(Ce) active collimator provided the best electronic collimation performance. However, for low radiation energies, the mechanical collimation images made from both scintillators showed the same quality, and, for high radiation energies, electronic collimation images made from both scintillators also show similar quality. Therefore, if mechanical collimation is used to detect low-energy radiation and electronic collimation is applied to reconstruct a high-energy source, either LaCl₃(Ce) or BGO would be appropriate for the active collimator of a dual γ-ray imager. These results broaden the choice of scintillators for the active collimator of the dual γ-ray imager, which makes it possible to consider other factors, such as machinability and cost, in making the imager. As a planar detector, BGO showed better performance than other scintillators since its radiation detection efficiency was highest of all. Copyright © 2011 Elsevier Ltd. All rights reserved.
Peroxisome Proliferator-Activated Receptors in Female Reproduction and Fertility
Carta, Gaspare; Artini, Paolo Giovanni
2016-01-01
Reproductive functions may be altered by the exposure to a multitude of endogenous and exogenous agents, drug or environmental pollutants, which are known to affect gene transcription through the peroxisome proliferator-activated receptors (PPARs) activation. PPARs act as ligand activated transcription factors and regulate metabolic processes such as lipid and glucose metabolism, energy homeostasis, inflammation, and cell proliferation and differentiation. All PPARs isotypes are expressed along the hypothalamic-pituitary-gonadal axis and are strictly involved in reproductive functions. Since female fertility and energy metabolism are tightly interconnected, the research on female infertility points towards the exploration of potential PPARs activating/antagonizing compounds, mainly belonging to the class of thiazolidinediones (TZDs) and fibrates, as useful agents for the maintenance of metabolic homeostasis in women with ovarian dysfunctions. In the present review, we discuss the recent evidence about PPARs expression in the hypothalamic-pituitary-gonadal axis and their involvement in female reproduction. Finally, the therapeutic potential of their manipulation through several drugs is also discussed. PMID:27559343
Factors affecting low back pain in adolescents.
Korovessis, Panagiotis; Repantis, Thomas; Baikousis, Andreas
2010-12-01
Prospective multifactorial study on low back pain (LBP) in adolescents. Most studies on LBP have focused on adults although many investigations have shown that the roots of LBP lie in adolescence. Several mechanical, physical, and behavioral factors have been associated with nonspecific LBP in adolescents. To investigate the effect of all previously reported parameters together with psychological and psychosocial factors using advanced statistics, on LBP in adolescents aged 15 to 19 years. Six hundred and eighty-eight students aged 16±1 years from 5 randomly selected high schools participated in this study and completed a questionnaire containing questions on daily activity, backpack carrying, psychological and psychosocial behavior. Anthropometric data as well as biplane spinal curvatures together with questionnaire results were included in the analysis using advanced statistics. LBP reported 41% of the participants. Generally, statistically significant correlations were found between LBP (0.002), physical activity (P<0.001), physician consultation (P=0.024), and depression (P<0.001). Sex-related differences were shown regarding LBP intensity (P=0.005) and frequency (P=0.013), stress (P<0.03), depression (P=0.005), and nervous mood (P=0.036) in favor of male students. Male adolescents had continuous energy (P=0.0258) and were calm (P=0.029) in contrast with female counterparts. LBP was sex-related and was less common in adolescents with frequent activity. Adolescent girls with stress, depressive mood, and low energy have more LBP than boys, which makes physician consultation for LBP more common in female adolescents. Systematic physical activity and control of psychological profile should decrease LBP frequency and intensity.
Public opinion on renewable energy: The nexus of climate, politics, and economy
NASA Astrophysics Data System (ADS)
Olson-Hazboun, Shawn K.
Increased use of renewable energy sources in the generation of electricity is a crucial component of transitioning to a less polluting energy system in the United States. Technologies like solar photovoltaic cells and wind turbines are being deployed at a rapid rate around the country, which means that an increasing portion of the public is becoming aware of renewable energy systems. The construction of these new industrial facilities has resulted in a variety of public reactions, positive and negative. Citizen opposition has been widely observed toward a variety of renewable energy facilities, and citizen groups can influence policy-making at the national, state, and local levels. Further research is needed to understand under what circumstances the public may take oppositional stances. To examine this topic, I analyze public perceptions of renewable energy using three different datasets. First, I used data from a survey conducted in 2014 in five communities in Utah, Wyoming, and Idaho experiencing renewable energy development (n=906). This dataset allowed me to untangle what factors help explain both individual as well as community-level variation in support for renewable energy. Second, I employed nationally representative survey data (n=13, 322) collected from 2008 to 2015 to examine the influence of a number of factors hypothesized to shape individuals' level of support for renewable energy policies including socio-demographic characteristics, political beliefs, belief in anthropogenic climate change, and nearby extractive industry activities. Last, I analyzed discourse about renewable energy in sixty-one semi-structured interviews with individuals representing various community sectors in three energy-producing rural communities in Utah. My research findings, on a whole, suggest that several place-based factors are significant in shaping public opinion about renewable energy, including community experience with renewable energy and local economic reliance on extractive industries. I also find pervasive climate skepticism across study sites. These findings indicate the need for broad-based and non-partisan discursive frames for renewable energy. Last, these findings speak to the importance of the 'just transitions' concepts, and the need to incorporate those communities most marginalized by the current system of fossil fuels extraction and production as society moves forward toward a cleaner energy economy.
Energetics of Na + Transport through the Electrode/Cathode Interface in Single Solvent Electrolytes
Browning, Katie L.; Sacci, Robert L.; Veith, Gabriel M.
2017-01-27
Here, the activation energy of desolvation for Na-ion electrolyte systems were studied using temperature dependent electrochemical impedance spectroscopy (EIS). Propylene carbonate (PC) and tetraglyme were chosen as solvents in single solvent electrolyte solution coupled with NaClO 4, NaPF 6, NaAsF 6, NaBF 4, and NaOFt salts. The results demonstrate the insertion and desolvation processes are extremely fast at or above room temperature. The data shows under optimal salt chemistry the desolvation activation energy is less than 21 kJ/mole. This is in contrast to the ~50 kJ/mole measured for analogous Li systems. The dominant factor affecting performance was the anion. Indeed,more » anions with lower donor numbers (PF 6 –, AsF 6 –) had more than 30 kJ/mole lower desolvation energies than species like NaBF 4 and NaOFt.« less
Controlling factors of recent clastic coastal sediments (Viransehir, Mersin bay, S Turkey)
NASA Astrophysics Data System (ADS)
Gül, Murat; Özbek, Ahmet; Kurt, Mehmet Ali; Zorlu, Kemal
2009-04-01
The Plio-Quaternary conglomeratic sets within the marine environment of the Viranşehir coast (W Mersin, S Turkey) are responsible for the evolution of sandy and gravely beaches due to their control on various factors such as sea floor irregularity, wave energy, and organic activity. The conglomeratic sets close to the shoreline (50-150 cm) act as wave breakers, creating hard substratum and high energy, well-oxygenated environment for organisms like Patella sp., Phoronida worms and Brachidontes pharaonis (Fischer P. 1870). The boring activities of these organisms have disintegrated the sandy matrix of these sets. Finer-grained matrix sediments have been transported to the interset and open sea, while cobble-pebbles have been carried landwards and have created imbricated gravely beach deposits without matrix. Sandy beach is evolving where the conglomeratic sets away from the shoreline (5.0-10.0 m). In this example, sets form a bar; causing fivefold division as backshore, berm, surf zone, bar and offshore from land to sea. Poorly sorted, cobbles-pebbles cobbles and pebbles are found associated with the high-energy environments of bars, whilst well-sorted sands are observed in low energetic environments on shore. The sets and recent shell fragments are the main sources of coastal sediments in Viranşehir. However, the amount of shell fragments decrease towards the active river mouth. This is due to sediment and fresh water influx from the river causing deteriorated temperature, salinity and light penetration of the marine environment resulting in less organic diversity.
Cold and hunger induce diurnality in a nocturnal mammal.
van der Vinne, Vincent; Riede, Sjaak J; Gorter, Jenke A; Eijer, Willem G; Sellix, Michael T; Menaker, Michael; Daan, Serge; Pilorz, Violetta; Hut, Roelof A
2014-10-21
The mammalian circadian system synchronizes daily timing of activity and rest with the environmental light-dark cycle. Although the underlying molecular oscillatory mechanism is well studied, factors that influence phenotypic plasticity in daily activity patterns (temporal niche switching, chronotype) are presently unknown. Molecular evidence suggests that metabolism may influence the circadian molecular clock, but evidence at the level of the organism is lacking. Here we show that a metabolic challenge by cold and hunger induces diurnality in otherwise nocturnal mice. Lowering ambient temperature changes the phase of circadian light-dark entrainment in mice by increasing daytime and decreasing nighttime activity. This effect is further enhanced by simulated food shortage, which identifies metabolic balance as the underlying common factor influencing circadian organization. Clock gene expression analysis shows that the underlying neuronal mechanism is downstream from or parallel to the main circadian pacemaker (the hypothalamic suprachiasmatic nucleus) and that the behavioral phenotype is accompanied by phase adjustment of peripheral tissues. These findings indicate that nocturnal mammals can display considerable plasticity in circadian organization and may adopt a diurnal phenotype when energetically challenged. Our previously defined circadian thermoenergetics hypothesis proposes that such circadian plasticity, which naturally occurs in nocturnal mammals, reflects adaptive maintenance of energy balance. Quantification of energy expenditure shows that diurnality under natural conditions reduces thermoregulatory costs in small burrowing mammals like mice. Metabolic feedback on circadian organization thus provides functional benefits by reducing energy expenditure. Our findings may help to clarify relationships between sleep-wake patterns and metabolic phenotypes in humans.
Rosado, Eliane Lopes; Bressan, Josefina; Martínez, J Alfredo
2015-05-01
Our aim was to evaluate the influence of the Gln27Glu polymorphism of the β2-adrenergic receptor (ADRβ2) gene, fat intake and physical activity on the energy expenditure (EE) and nutritional status of obese women. Sixty obese women (30-46 years) participated in the study and were assigned to three groups depending on the genotypes: Gln27Gln, Gln27Glu and Glu27Glu. At baseline and after nutritional intervention, the anthropometric and body composition (bioelectrical impedance), dietary, EE (indirect calorimetry) and biochemical variables were measured. All women received a high-fat test meal to determine the postprandial EE (short-term) and an energy-restricted diet for 10 weeks (long term). The frequencies of Gln27Gln, Gln27Glu and Glu27Glu were 36.67, 40.0 and 23.33 %, respectively. Anthropometric and biochemical variables and EE did not differ between groups, although women who had no polymorphism demonstrated decreased carbohydrate oxidation. On the other hand, the Glu27Glu genotype showed a positive relation with EE in physical activity and fat oxidation. The environmental factors and Gln27Glu polymorphism did not influence the nutritional status and EE of obese women, but physical activity in obese women with the polymorphism in the ADRβ2 gene can promote fat oxidation. The results suggest that encouraging the practice of physical exercise is important considering the high frequency of this polymorphism in obese subjects.
Anaerobic sequencing batch reactor in pilot scale for treatment of tofu industry wastewater
NASA Astrophysics Data System (ADS)
Rahayu, Suparni Setyowati; Purwanto, Budiyono
2015-12-01
The small industry of tofu production process releases the waste water without being processed first, and the wastewater is directly discharged into water. In this study, Anaerobic Sequencing Batch Reactor in Pilot Scale for Treatment of Tofu Industry was developed through an anaerobic process to produce biogas as one kind of environmentally friendly renewable energy which can be developed into the countryside. The purpose of this study was to examine the fundamental characteristics of organic matter elimination of industrial wastewater with small tofu effective method and utilize anaerobic active sludge with Anaerobic Sequencing Bath Reactor (ASBR) to get rural biogas as an energy source. The first factor is the amount of the active sludge concentration which functions as the decomposers of organic matter and controlling selectivity allowance to degrade organic matter. The second factor is that HRT is the average period required substrate to react with the bacteria in the Anaerobic Sequencing Bath Reactor (ASBR).The results of processing the waste of tofu production industry using ASBR reactor with active sludge additions as starter generates cumulative volume of 5814.4 mL at HRT 5 days so that in this study it is obtained the conversion 0.16 L of CH4/g COD and produce biogas containing of CH4: 81.23% and CO2: 16.12%. The wastewater treatment of tofu production using ASBR reactor is able to produce renewable energy that has economic value as well as environmentally friendly by nature.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rahayu, Suparni Setyowati, E-mail: suparnirahayu@yahoo.co.id; Department of Mechanical Engineering, State Polytechnic of Semarang, Semarang Indonesia; Purwanto,, E-mail: p.purwanto@che.undip.ac.id
The small industry of tofu production process releases the waste water without being processed first, and the wastewater is directly discharged into water. In this study, Anaerobic Sequencing Batch Reactor in Pilot Scale for Treatment of Tofu Industry was developed through an anaerobic process to produce biogas as one kind of environmentally friendly renewable energy which can be developed into the countryside. The purpose of this study was to examine the fundamental characteristics of organic matter elimination of industrial wastewater with small tofu effective method and utilize anaerobic active sludge with Anaerobic Sequencing Bath Reactor (ASBR) to get rural biogasmore » as an energy source. The first factor is the amount of the active sludge concentration which functions as the decomposers of organic matter and controlling selectivity allowance to degrade organic matter. The second factor is that HRT is the average period required substrate to react with the bacteria in the Anaerobic Sequencing Bath Reactor (ASBR).The results of processing the waste of tofu production industry using ASBR reactor with active sludge additions as starter generates cumulative volume of 5814.4 mL at HRT 5 days so that in this study it is obtained the conversion 0.16 L of CH{sub 4}/g COD and produce biogas containing of CH{sub 4}: 81.23% and CO{sub 2}: 16.12%. The wastewater treatment of tofu production using ASBR reactor is able to produce renewable energy that has economic value as well as environmentally friendly by nature.« less
The role of elastic energy in activities with high force and power requirements: a brief review.
Wilson, Jacob M; Flanagan, Eamonn P
2008-09-01
The purpose of this article is to provide strength and conditioning practitioners with an understanding of the role of elastic energy in activities with high force and power requirements. Specifically, the article covers 1) the nature of elasticity and its application to human participants, 2) the role of elastic energy in activities requiring a stretch-shorten cycle such as the vertical jump, 3) the role of muscular stiffness in athletic performance, 4) the control of muscular stiffness through feedforward and feedback mechanisms, and 5) factors affecting muscular stiffness. Finally, practical applications are provided. In this section, it is suggested that the storage and reuse of elastic energy is optimized at relatively higher levels of stiffness. Because stiffness decreases as fatigue ensues as well as with stretching before an event, the article emphasizes the need for proper preparation phases in a periodized cycle and the avoidance of long static stretches before high-force activities. The importance of teaching athletes to transition from eccentric to concentric movements with minimal time delays is also proposed due to the finding that time delays appear to decrease the reuse of elastic energy. In addition to teaching within the criterion tasks, evidence is provided that minimizing transitions in plyometric training, a technique demonstrated to increase musculotendinous stiffness, can optimize power output in explosive movements. Finally, evidence is provided that training and teaching programs designed to optimize muscular stiffness may protect athletes against sports-related injuries.
Physical activity and dark skin tone: protective factors against low bone mass in Mexican men.
Vivanco-Muñoz, Nalleli; Jo, Talavera; Gerardo, Huitron-Bravo; Juan, Tamayo; Clark, Patricia
2012-01-01
A cross-sectional study was conducted on 268 Mexican men between the ages of 13 and 80 yr to evaluate the association of clinical factors related with bone mass. Men from high schools, universities, and retirement homes were invited to participate. Body mass index (BMI) was measured, and bone mineral density (BMD) was assessed using dual-energy X-ray absorptiometry for L1-L4 and total hip. Factors related to bone mass were assessed by questionnaire and analyzed using a logistic regression model. Demographic factors (age, education, and occupation), clinical data (BMI, skin tone, previous fracture, history of osteoporosis [OP], and history of fractures), and lifestyle variables (diet, physical activity, sun exposure, and smoking) were evaluated. Physical activity (≥ 60 min/5 times a week) reduced the risk for low BMD for age, osteopenia, and OP at the spine and total hip (odds ratio [OR]: 0.276; 95% confidence interval [CI]: 0.099-0.769; p=0.014; and OR: 0.184; 95% CI: 0.04-0.849; p=0.03, respectively). Dark skin tone was a protective factor, decreasing the risk by up to 70%. In this population of healthy Mexican men (aged 13-80 yr), dark skin and physical activity were protective factors against low bone mass. Copyright © 2012 The International Society for Clinical Densitometry. Published by Elsevier Inc. All rights reserved.
ERIC Educational Resources Information Center
Metz, Ron
This instructional unit is one of 10 developed by students on various energy-related areas that deals specifically with weatherizing a structure. Its objective is for the student to be able to analyze factors related to specific structures that indicate need for weatherizing activities and to determine steps to correct defects in structures that…
Chu, Yuzhuo; Yao, Jianzhuang; Guo, Hong
2012-05-18
Certain lysine residues on histone tails could be methylated by protein lysine methyltransferases (PKMTs) using S-adenosyl-L-methionine (AdoMet) as the methyl donor. Since the methylation states of the target lysines play a fundamental role in the regulation of chromatin structure and gene expression, it is important to study the property of PKMTs that allows a specific number of methyl groups (one, two or three) to be added (termed as product specificity). It has been shown that the product specificity of PKMTs may be controlled in part by the existence of specific residues at the active site. One of the best examplesmore » is a Phe/Tyr switch found in many PKMTs. Here quantum mechanical/molecular mechanical (QM/MM) molecular dynamics (MD) and free energy simulations are performed on wild type G9a-like protein (GLP) and its F1209Y and Y1124F mutants for understanding the energetic origin of the product specificity and the reasons for the change of product specificity as a result of single-residue mutations at the Phe/Tyr switch as well as other positions. The free energy barriers of the methyl transfer processes calculated from our simulations are consistent with experimental data, supporting the suggestion that the relative free energy barriers may determine, at least in part, the product specificity of PKMTs. The changes of the free energy barriers as a result of the mutations are also discussed based on the structural information obtained from the simulations. Furthermore, the results suggest that the space and active-site interactions around the -amino group of the target lysine available for methyl addition appear to among the key structural factors in controlling the product specificity and activity of PKMTs.« less
Combination of physical activity, nutrition, or other metabolic factors and vaccine response
Hance, Kenneth W.; Rogers, Connie J.; Hursting, Stephen D.; Greiner, John W.
2010-01-01
A number of lifestyle factors that reduce cancer risk in the primary prevention setting may be potential new targets for use in combination with cancer vaccines. This review discusses the modulation of energy balance (physical activity, calorie restriction, and obesity prevention), and the supplementation with natural and synthetic analogs of vitamins A and E, as potential interventions for use in combination with cancer vaccines. Additionally, the pharmacologic manipulation of nutrient metabolism in the tumor microenvironment (e.g., arachidonic acid, arginine, tryptophan, and glucose metabolism) is discussed. This review includes a brief overview of the role of each agent in primary cancer prevention; outlines the effects of these agents on immune function, specifically adaptive and/or anti-tumor immune mechanisms, when known; and discusses the potential use of these interventions in combination with therapeutic cancer vaccines. Modulation of energy balance through exercise and strategies targeting nutrient metabolism in the tumor microenvironment represent the most promising interventions to partner with therapeutic cancer vaccines. Additionally, the use of vitamin E succinate and the retinoid X receptor-directed rexinoids in combination with cancer vaccines offer promise. In summary, a number of energy balance- and nutrition-related interventions are viable candidates for further study in combination with cancer vaccines. PMID:17569626
“Rocking-Chair”-Type Metal Hybrid Supercapacitors
Yoo, Hyun Deog; Han, Sang-Don; Bayliss, Ryan D.; ...
2016-10-24
Hybrid supercapacitors that follow a “rocking-chair”-type mechanism were developed by coupling divalent metal and activated carbon electrodes in nonaqueous electrolytes. Conventional supercapacitors require a large amount of electrolyte to provide a sufficient quantity of ions to the electrodes, due to their Daniell-type mechanism that depletes the ions from the electrolyte while charging. The alternative “rocking-chair”-type mechanism effectively enhances the energy density of supercapacitors by minimizing the necessary amount of electrolyte, because the ion is replenished from the metal anode while it is adsorbed to the cathode. Newly developed nonaqueous electrolytes for Mg and Zn electrochemistry, based on bis(trifluoromethylsulfonyl)imide (TFSI) salts,more » made the metal hybrid supercapacitors possible by enabling reversible deposition on the metal anodes and reversible adsorption on an activated carbon cathode. Factoring in gains through the cell design, the energy density of the metal hybrid supercapacitors is projected to be a factor of 7 higher than conventional devices thanks to both the “rocking-chair”-type mechanism that minimizes total electrolyte volume and the use of metal anodes, which have substantial merits in capacity and voltage. Self-discharge was also substantially alleviated compared to conventional supercapacitors. This concept offers a route to build supercapacitors that meet dual criteria of power and energy densities with a simple cell design.« less
"Rocking-Chair"-Type Metal Hybrid Supercapacitors.
Yoo, Hyun Deog; Han, Sang-Don; Bayliss, Ryan D; Gewirth, Andrew A; Genorio, Bostjan; Rajput, Nav Nidhi; Persson, Kristin A; Burrell, Anthony K; Cabana, Jordi
2016-11-16
Hybrid supercapacitors that follow a "rocking-chair"-type mechanism were developed by coupling divalent metal and activated carbon electrodes in nonaqueous electrolytes. Conventional supercapacitors require a large amount of electrolyte to provide a sufficient quantity of ions to the electrodes, due to their Daniell-type mechanism that depletes the ions from the electrolyte while charging. The alternative "rocking-chair"-type mechanism effectively enhances the energy density of supercapacitors by minimizing the necessary amount of electrolyte, because the ion is replenished from the metal anode while it is adsorbed to the cathode. Newly developed nonaqueous electrolytes for Mg and Zn electrochemistry, based on bis(trifluoromethylsulfonyl)imide (TFSI) salts, made the metal hybrid supercapacitors possible by enabling reversible deposition on the metal anodes and reversible adsorption on an activated carbon cathode. Factoring in gains through the cell design, the energy density of the metal hybrid supercapacitors is projected to be a factor of 7 higher than conventional devices thanks to both the "rocking-chair"-type mechanism that minimizes total electrolyte volume and the use of metal anodes, which have substantial merits in capacity and voltage. Self-discharge was also substantially alleviated compared to conventional supercapacitors. This concept offers a route to build supercapacitors that meet dual criteria of power and energy densities with a simple cell design.
Zhuang, Zhihao; Yoder, Bonita L; Burgers, Peter M J; Benkovic, Stephen J
2006-02-21
Numerous proteins that function in DNA metabolic pathways are known to interact with the proliferating cell nuclear antigen (PCNA). The important function of PCNA in stimulating various cellular activities requires its topological linkage with DNA. Loading of the circular PCNA onto duplex DNA requires the activity of a clamp-loader [replication factor C (RFC)] complex and the energy derived from ATP hydrolysis. The mechanistic and structural details regarding PCNA loading by the RFC complex are still developing. In particular, the positive identification of a long-hypothesized structure of an open clamp-RFC complex as an intermediate in loading has remained elusive. In this study, we capture an open yeast PCNA clamp in a complex with RFC through fluorescence energy transfer experiments. We also follow the topological transitions of PCNA in the various steps of the clamp-loading pathway through both steady-state and stopped-flow fluorescence studies. We find that ATP effectively drives the clamp-loading process to completion with the formation of the closed PCNA bound to DNA, whereas ATPgammaS cannot. The information derived from this work complements that obtained from previous structural and mechanistic studies and provides a more complete picture of a eukaryotic clamp-loading pathway using yeast as a paradigm.
Rothman, Sarah M; Griffioen, Kathleen J; Wan, Ruiqian; Mattson, Mark P
2012-01-01
Overweight sedentary individuals are at increased risk for cardiovascular disease, diabetes, and some neurological disorders. Beneficial effects of dietary energy restriction (DER) and exercise on brain structural plasticity and behaviors have been demonstrated in animal models of aging and acute (stroke and trauma) and chronic (Alzheimer's and Parkinson's diseases) neurological disorders. The findings described later, and evolutionary considerations, suggest brain-derived neurotrophic factor (BDNF) plays a critical role in the integration and optimization of behavioral and metabolic responses to environments with limited energy resources and intense competition. In particular, BDNF signaling mediates adaptive responses of the central, autonomic, and peripheral nervous systems from exercise and DER. In the hypothalamus, BDNF inhibits food intake and increases energy expenditure. By promoting synaptic plasticity and neurogenesis in the hippocampus, BDNF mediates exercise- and DER-induced improvements in cognitive function and neuroprotection. DER improves cardiovascular stress adaptation by a mechanism involving enhancement of brainstem cholinergic activity. Collectively, findings reviewed in this paper provide a rationale for targeting BDNF signaling for novel therapeutic interventions in a range of metabolic and neurological disorders. PMID:22548651
NASA Astrophysics Data System (ADS)
Zhu, Yawen; Cui, Xiaohong; Wang, Qianqian; Tong, Qiujie; Cui, Xutai; Li, Chenyu; Zhang, Le; Peng, Zhong
2016-11-01
The hardware-in-the-loop simulation system, which provides a precise, controllable and repeatable test conditions, is an important part of the development of the semi-active laser (SAL) guided weapons. In this paper, laser energy chain characteristics were studied, which provides a theoretical foundation for the SAL guidance technology and the hardware-in-the-loop simulation system. Firstly, a simplified equation was proposed to adjust the radar equation according to the principles of the hardware-in-the-loop simulation system. Secondly, a theoretical model and calculation method were given about the energy chain characteristics based on the hardware-in-the-loop simulation system. We then studied the reflection characteristics of target and the distance between the missile and target with major factors such as the weather factors. Finally, the accuracy of modeling was verified by experiment as the values measured experimentally generally follow the theoretical results from the model. And experimental results revealed that ratio of attenuation of the laser energy exhibited a non-linear change vs. pulse number, which were in accord with the actual condition.
Synthesis, thermolysis, and sensitivities of HMX/NC energetic nanocomposites.
Wang, Yi; Song, Xiaolan; Song, Dan; Liang, Li; An, Chongwei; Wang, Jingyu
2016-07-15
1,3,5,7-Tetranittro-1,3,5,7-tetrazocane/nitrocellulose (HMX/NC) nanocomposites were successfully synthesized by an improved sol-gel-supercritical method. NC nanoparticles with a size of ∼30nm were cross-linked to form a network structure, and HMX nanoparticles were imbedded in the nano-NC matrix. The key factors, i.e., the selection of catalyst and solvent, were probed. No phase transformation of the HMX occurred before or after fabrication, and the molecular structures of the HMX and NC did not change. Thermal analyses were performed, and the kinetic and thermodynamic parameters, such as activation energy (EK), per-exponent factor (lnAK), rate constant (k), activation heat (ΔH(≠)), activation free energy (ΔG(≠)), activation entropy (ΔS(≠)), critical temperature of thermal explosion (Tb), and critical heating rate of thermal explosion (dT/dt)Tb, were calculated. The results indicate that HMX/NC presented a much lower activation energy (165.03kJ/mol) than raw HMX (282.5kJ/mol) or raw NC (175.51kJ/mol). The chemical potential (ΔG(≠)) for the thermal decomposition of HMX/NC has a positive value, which means that the activation of the molecules would not proceed spontaneously. The significantly lower ΔH(≠) value of HMX/NC, which represents the heat needed to be absorbed by an explosive molecule to change it from its initial state to an activated state, implies that the molecules of HMX/NC are much easier to be activated than those of raw HMX. Similarly, the HMX/NC presented a much lower Tb (168.2°C) than raw HMX (283.2°C). From the results of the sensitivity tests, the impact and friction sensitivities of HMX/NC were significantly decreased compared with those of raw HMX, but the thermal sensitivity was distinctly higher. The activation of the particles under external stimulation was simulated, and the mechanism was found to be crucial. Combining the thermodynamic parameters, the mechanism as determined from the results of the sensitivity tests was discussed in detail. Copyright © 2016 Elsevier B.V. All rights reserved.
Can exergaming contribute to improving physical activity levels and health outcomes in children?
Daley, Amanda J
2009-08-01
Physical inactivity among children is a serious public health problem. It has been suggested that high levels of screen time are contributory factors that encourage sedentary lifestyles in young people. As physical inactivity and obesity levels continue to rise in young people, it has been proposed that new-generation active computer- and video-console games (otherwise known as "exergaming") may offer the opportunity to contribute to young people's energy expenditure during their free time. Although studies have produced some encouraging results regarding the energy costs involved in playing active video-console games, the energy costs of playing the authentic versions of activity-based video games are substantially larger, highlighting that active gaming is no substitute for real sports and activities. A small number of exergaming activities engage children in moderate-intensity activity, but most do not. Only 3 very small trials have considered the effects of exergaming on physical activity levels and/or other health outcomes in children. Evidence from these trials has been mixed; positive trends for improvements in some health outcomes in the intervention groups were noted in 2 trials. No adequately powered randomized, controlled trial has been published to date, and no trial has assessed the long-term impact of exergaming on children's health. We now need high-quality randomized, controlled trials to evaluate the effectiveness and sustainability of exergaming, as well as its clinical relevance; until such studies take place, we should remain cautious about its ability to positively affect children's health.
Differences in the utilisation of active power in squat and countermovement jumps.
Ferraro, Damián; Fábrica, Gabriel
2017-07-01
The aim of this article was to understand how active power is used in squat and countermovement jumps. A simple empirical model comprising a mass, a spring, an active element and a damper, together with an optimisation principle, was used to identify the mechanical factors that maximise performance of jumps without countermovement (squat jumps, SJ) and with countermovement (CMJ). Twelve amateur volleyball players performed SJ from two initial positions and CMJ with two degrees of counterbalancing, while kinematic data were collected (jump height, push-off duration and position of the centre of mass). The model adjusted well to real data of SJ through all the impulse phase, and slightly less adequately at the end of this phase for CMJ. Nevertheless, it provides a satisfactory explanation for the generation and utilisation of active power for both type of jumps. On average, the estimated power of the active elements, the spring, and the damper were greater in the SJ. Based upon the result obtained with this model, we suggest that active power is best evaluated with SJ. The reason for this is that, during this kind of jump, the elements associated with the damper consume much of the energy produced by the active elements. The participation of the elements that consume the energy generated by the active elements is less in CMJ than in SJ, allowing for a better utilisation of this energy. In this way it is possible to achieve a better performance in CMJ with less active power.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Elbert, Katherine; Hu, Jue; Ma, Zhong
Hydrogen oxidation and evolution on Pt in acid are facile processes, while in alkaline electrolytes, they are 2 orders of magnitude slower. Thus, developing catalysts that are more active than Pt for these two reactions is important for advancing the performance of anion exchange membrane fuel cells and water electrolyzers. Herein, we detail a 4-fold enhancement of Pt mass activity that we achieved using single-crystalline Ru@Pt core–shell nanoparticles with two-monolayer-thick Pt shells, which doubles the activity on Pt–Ru alloy nanocatalysts. For Pt specific activity, the two- and one-monolayer-thick Pt shells exhibited enhancement factors of 3.1 and 2.3, respectively, compared tomore » the Pt nanocatalysts in base, differing considerably from the values of 1 and 0.4, respectively, in acid. To explain such behavior and the orders of magnitude difference in activity on going from acid to base, we performed kinetic analyses of polarization curves over a wide range of potential from –250 to 250 mV using the dual-pathway kinetic equation. From acid to base, the activation free energies increase the most for the Volmer reaction, resulting in a switch of the rate-determining step from the Tafel to the Volmer reaction, and a shift to a weaker optimal hydrogen binding energy. Furthermore, the much higher activation barrier for the Volmer reaction in base than in acid is ascribed to one or both of the two catalyst-insensitive factors: slower transport of OH – than H + in water and a stronger O–H bond in water molecules (HO–H) than in hydrated protons (H 2O–H +).« less
Yao, Fan; Zhang, Ming; Chen, Li
2015-01-01
Diabetes mellitus (DM), an endocrine disorder, will be one of the leading causes of death world-wide in about two decades. Cellular injuries and disorders of energy metabolism are two key factors in the pathogenesis of diabetes, which also become the important causes for the process of diabetic complications. AMPK is a key enzyme in maintaining metabolic homeostasis and has been implicated in the activation of autophagy in distinct tissues. An increasing number of researchers have confirmed that autophagy is a potential factor to affect or induce diabetes and its complications nowadays, which could remove cytotoxic proteins and dysfunctional organelles. This review will summarize the regulation of autophagy and AMPK in diabetes and its complications, and explore how AMPK stimulates autophagy in different diabetic syndromes. A deeper understanding of the regulation and activity of AMPK in autophagy would enhance its development as a promising therapeutic target for diabetes treatment. PMID:26904395
Yao, Fan; Zhang, Ming; Chen, Li
2016-01-01
Diabetes mellitus (DM), an endocrine disorder, will be one of the leading causes of death world-wide in about two decades. Cellular injuries and disorders of energy metabolism are two key factors in the pathogenesis of diabetes, which also become the important causes for the process of diabetic complications. AMPK is a key enzyme in maintaining metabolic homeostasis and has been implicated in the activation of autophagy in distinct tissues. An increasing number of researchers have confirmed that autophagy is a potential factor to affect or induce diabetes and its complications nowadays, which could remove cytotoxic proteins and dysfunctional organelles. This review will summarize the regulation of autophagy and AMPK in diabetes and its complications, and explore how AMPK stimulates autophagy in different diabetic syndromes. A deeper understanding of the regulation and activity of AMPK in autophagy would enhance its development as a promising therapeutic target for diabetes treatment.
Zhu, Y C; Zhu, Y Z; Spitznagel, H; Gohlke, P; Unger, T
1996-01-01
Left ventricular hypertrophy is considered to be an independent risk factor giving rise to ischemia, arrhythmias, and left ventricular dysfunction. Slow movement of intracellular calcium contributes to the impaired contraction and relaxation function of hypertrophied myocardium. Myofibril content may also be shifted to fetal-type isoforms with decreased contraction and relaxation properties in left ventricular hypertrophy. Myocyte hypertrophy and interstitial fibrosis are regulated independently by mechanical and neurohumoral mechanisms. In severely hypertrophied myocardium, capillary density is reduced, the diffusion distance for oxygen, nutrients, and metabolites is increased, and the ratio of energy-production sites to energy-consumption sites is decreased. The metabolic state of severely hypertrophied myocardium is anaerobic, as indicated by the shift of lactate dehydrogenase marker enzymes. Therefore, the hypertrophied myocardium is more vulnerable to ischemic events. As a compensatory response to severe cardiac hypertrophy and congestive heart failure, the ADP/ATP carrier is activated and atrial natriuretic peptide is released to increase high-energy phosphate production and reduce cardiac energy consumption by vasodilation and sodium and fluid elimination. However, in severely hypertrophied and failing myocardium, vasoconstrictor and sodium- and fluid-retaining factors, such as the renin-angiotensin system, aldosterone, and sympathetic nerve activity, play an overwhelming role. Angiotensin-converting enzyme inhibitors (ACEIs) are able to prevent cardiac hypertrophy and improve cardiac function and metabolism. Under experimental conditions, these beneficial effects can be ascribed mainly to bradykinin potentiation, although a contribution of the ACEI-induced angiotensin II reduction cannot be excluded.
Nadar, M Y; Akar, D K; Rao, D D; Kulkarni, M S; Pradeepkumar, K S
2015-12-01
Assessment of intake due to long-lived actinides by inhalation pathway is carried out by lung monitoring of the radiation workers inside totally shielded steel room using sensitive detection systems such as Phoswich and an array of HPGe detectors. In this paper, uncertainties in the lung activity estimation due to positional errors, chest wall thickness (CWT) and detector background variation are evaluated. First, calibration factors (CFs) of Phoswich and an array of three HPGe detectors are estimated by incorporating ICRP male thorax voxel phantom and detectors in Monte Carlo code 'FLUKA'. CFs are estimated for the uniform source distribution in lungs of the phantom for various photon energies. The variation in the CFs for positional errors of ±0.5, 1 and 1.5 cm in horizontal and vertical direction along the chest are studied. The positional errors are also evaluated by resizing the voxel phantom. Combined uncertainties are estimated at different energies using the uncertainties due to CWT, detector positioning, detector background variation of an uncontaminated adult person and counting statistics in the form of scattering factors (SFs). SFs are found to decrease with increase in energy. With HPGe array, highest SF of 1.84 is found at 18 keV. It reduces to 1.36 at 238 keV. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Kilbride, Seán M.; Farrelly, Angela M.; Bonner, Caroline; Ward, Manus W.; Nyhan, Kristine C.; Concannon, Caoimhín G.; Wollheim, Claes B.; Byrne, Maria M.; Prehn, Jochen H. M.
2010-01-01
Heterozygous loss-of-function mutations in the hepatocyte nuclear factor 1A (HNF1A) gene result in the pathogenesis of maturity-onset diabetes-of-the-young type 3, (HNF1A-MODY). This disorder is characterized by a primary defect in metabolism-secretion coupling and decreased beta cell mass, attributed to excessive beta cell apoptosis. Here, we investigated the link between energy stress and apoptosis activation following HNF1A inactivation. This study employed single cell fluorescent microscopy, flow cytometry, gene expression analysis, and gene silencing to study the effects of overexpression of dominant-negative (DN)-HNF1A expression on cellular bioenergetics and apoptosis in INS-1 cells. Induction of DN-HNF1A expression led to reduced ATP levels and diminished the bioenergetic response to glucose. This was coupled with activation of the bioenergetic stress sensor AMP-activated protein kinase (AMPK), which preceded the onset of apoptosis. Pharmacological activation of AMPK using aminoimidazole carboxamide ribonucleotide (AICAR) was sufficient to induce apoptosis in naive cells. Conversely, inhibition of AMPK with compound C or AMPKα gene silencing protected against DN-HNF1A-induced apoptosis. Interestingly, AMPK mediated the induction of the pro-apoptotic Bcl-2 homology domain-3-only protein Bmf (Bcl-2-modifying factor). Bmf expression was also elevated in islets of DN-HNF1A transgenic mice. Furthermore, knockdown of Bmf expression in INS-1 cells using siRNA was sufficient to protect against DN-HNF1A-induced apoptosis. Our study suggests that overexpression of DN-HNF1A induces bioenergetic stress and activation of AMPK. This in turn mediates the transcriptional activation of the pro-apoptotic Bcl-2-homology protein BMF, coupling prolonged energy stress to apoptosis activation. PMID:20841353
Holidays in lights: Tracking cultural patterns in demand for energy services
NASA Astrophysics Data System (ADS)
Román, Miguel O.; Stokes, Eleanor C.
2015-06-01
Successful climate change mitigation will involve not only technological innovation, but also innovation in how we understand the societal and individual behaviors that shape the demand for energy services. Traditionally, individual energy behaviors have been described as a function of utility optimization and behavioral economics, with price restructuring as the dominant policy lever. Previous research at the macro-level has identified economic activity, power generation and technology, and economic role as significant factors that shape energy use. However, most demand models lack basic contextual information on how dominant social phenomenon, the changing demographics of cities, and the sociocultural setting within which people operate, affect energy decisions and use patterns. Here we use high-quality Suomi-NPP VIIRS nighttime environmental products to: (1) observe aggregate human behavior through variations in energy service demand patterns during the Christmas and New Year's season and the Holy Month of Ramadan and (2) demonstrate that patterns in energy behaviors closely track sociocultural boundaries at the country, city, and district level. These findings indicate that energy decision making and demand is a sociocultural process as well as an economic process, often involving a combination of individual price-based incentives and societal-level factors. While nighttime satellite imagery has been used to map regional energy infrastructure distribution, tracking daily dynamic lighting demand at three major scales of urbanization is novel. This methodology can enrich research on the relative importance of drivers of energy demand and conservation behaviors at fine scales. Our initial results demonstrate the importance of seating energy demand frameworks in a social context.
Holiday in Lights: Tracking Cultural Patterns in Demand for Energy Services
NASA Technical Reports Server (NTRS)
Roman, Miguel O.; Stokes, Eleanor C.
2015-01-01
Successful climate change mitigation will involve not only technological innovation, but also innovation in how we understand the societal and individual behaviors that shape the demand for energy services. Traditionally, individual energy behaviors have been described as a function of utility optimization and behavioral economics, with price restructuring as the dominant policy lever. Previous research at the macro-level has identified economic activity, power generation and technology, and economic role as significant factors that shape energy use. However, most demand models lack basic contextual information on how dominant social phenomenon, the changing demographics of cities, and the sociocultural setting within which people operate, affect energy decisions and use patterns. Here we use high-quality Suomi-NPP VIIRS nighttime environmental products to: (1) observe aggregate human behavior through variations in energy service demand patterns during the Christmas and New Year's season and the Holy Month of Ramadan and (2) demonstrate that patterns in energy behaviors closely track sociocultural boundaries at the country, city, and district level. These findings indicate that energy decision making and demand is a sociocultural process as well as an economic process, often involving a combination of individual price-based incentives and societal-level factors. While nighttime satellite imagery has been used to map regional energy infrastructure distribution, tracking daily dynamic lighting demand at three major scales of urbanization is novel. This methodology can enrich research on the relative importance of drivers of energy demand and conservation behaviors at fine scales. Our initial results demonstrate the importance of seating energy demand frameworks in a social context.
Holidays in lights: Tracking cultural patterns in demand for energy services.
Román, Miguel O; Stokes, Eleanor C
2015-06-01
Successful climate change mitigation will involve not only technological innovation, but also innovation in how we understand the societal and individual behaviors that shape the demand for energy services. Traditionally, individual energy behaviors have been described as a function of utility optimization and behavioral economics, with price restructuring as the dominant policy lever. Previous research at the macro-level has identified economic activity, power generation and technology, and economic role as significant factors that shape energy use. However, most demand models lack basic contextual information on how dominant social phenomenon, the changing demographics of cities, and the sociocultural setting within which people operate, affect energy decisions and use patterns. Here we use high-quality Suomi-NPP VIIRS nighttime environmental products to: (1) observe aggregate human behavior through variations in energy service demand patterns during the Christmas and New Year's season and the Holy Month of Ramadan and (2) demonstrate that patterns in energy behaviors closely track sociocultural boundaries at the country, city, and district level. These findings indicate that energy decision making and demand is a sociocultural process as well as an economic process, often involving a combination of individual price-based incentives and societal-level factors. While nighttime satellite imagery has been used to map regional energy infrastructure distribution, tracking daily dynamic lighting demand at three major scales of urbanization is novel. This methodology can enrich research on the relative importance of drivers of energy demand and conservation behaviors at fine scales. Our initial results demonstrate the importance of seating energy demand frameworks in a social context.
Integrated actuation and energy harvesting in prestressed piezoelectric synthetic jets
NASA Astrophysics Data System (ADS)
Mane, Poorna
With the looming energy crisis compounded by the global economic downturn there is an urgent need to increase energy efficiency and to discover new energy sources. An approach to solve this problem is to improve the efficiency of aerodynamic vehicles by using active flow control tools such as synthetic jet actuators. These devices are able to reduce fuel consumption and streamlined vehicle design by reducing drag and weight, and increasing maneuverability. Hence, the main goal of this dissertation is to study factors that affect the efficiency of synthetic jets by incorporating energy harvesting into actuator design using prestressed piezoelectric composites. Four state-of-the-art piezoelectric composites were chosen as active diaphragms in synthetic jet actuators. These composites not only overcome the inherent brittle and fragile nature of piezoelectric materials but also enhance domain movement which in turn enhances intrinsic contributions. With these varying characteristics among different types of composites, the intricacies of the synthetic jet design and its implementation increases. In addition the electrical power requirements of piezoelectric materials make the new SJA system a coupled multiphysics problem involving electro-mechanical and structural-fluid interactions. Due to the nature of this system, a design of experiments approach, a method of combining experiments and statistics, is utilized. Geometric and electro-mechanical factors are investigated using a fractional factorial design with peak synthetic jet velocity as a response variable. Furthermore, energy generated by the system oscillations is harvested with a prestressed composite and a piezo-polymer. Using response surface methodology the process is optimized under different temperatures and pressures to simulate harsh environmental conditions. Results of the fractional factorial experimental design showed that cavity dimensions and type of signal used to drive the synthetic jet actuator were statistically significant factors when studying peak jet velocity. The Bimorph (˜50m/s) and the prestressed metal composite (˜45m/s) generated similar peak jet velocities but the later is the most robust of all tested actuators. In addition, an alternate input signal to the composite, a sawtooth waveform, leads to jets formed with larger peak velocities at frequencies above 15Hz. The optimized factor levels for the energy harvesting process were identified as 237.6kPa, 3.7Hz, 1MO and 12°C and the power density measured at these conditions was 24.27microW/mm3. Finally, the SJA is integrated with an energy harvesting system and the power generated is stored into a large capacitor and a rechargeable battery. After approximately six hours of operation 5V of generated voltage is stored in a 330microF capacitor with the prestressed metal composite as the harvester. It is then demonstrated that energy harvested from the inherent vibrations of a SJA can be stored for later use. Then, the system proposed in this dissertation not only improves on the efficiency of aerodynamic bodies, but also harvests energy that is otherwise wasted.
Variability in HOMA-IR, lipoprotein profile and selected hormones in young active men.
Keska, Anna; Lutoslawska, Grazyna; Czajkowska, Anna; Tkaczyk, Joanna; Mazurek, Krzysztof
2013-01-01
Resistance to insulin actions is contributing to many metabolic disturbances. Such factors as age, sex, nutrition, body fat, and physical activity determine body insulin resistance. Present study attempted to asses insulin resistance and its metabolic effects with respect to energy intake in young, lean, and active men. A total of 87 men aged 18-23 participated in the study. Plasma levels of glucose, insulin, lipoproteins, cortisol, and TSH were determined. Insulin resistance was expressed as Homeostasis Model Assessment for Insulin Resistance (HOMA-IR) and calculated using homeostatic model. The median value of HOMA-IR (1.344) was used to divide subjects into two groups. Men did not differ in anthropometric parameters, daily physical activity, and plasma TSH and cortisol levels. However, in men with higher HOMA-IR significantly lower daily energy intake was observed concomitantly with higher TG, TC, and HDL-C concentrations in plasma versus their counterparts with lower HOMA-IR. Exclusively in subjects with higher HOMA-IR significant and positive correlation was noted between HOMA-IR and TC and LDL-C. We concluded that despite a normal body weight and physical activity, a subset of young men displayed unfavorable changes in insulin sensitivity and lipid profile, probably due to insufficient energy intake.
Okumura, Cheryl Y M; Hollands, Andrew; Tran, Dan N; Olson, Joshua; Dahesh, Samira; von Köckritz-Blickwede, Maren; Thienphrapa, Wdee; Corle, Courtney; Jeung, Seung Nam; Kotsakis, Anna; Shalwitz, Robert A; Johnson, Randall S; Nizet, Victor
2012-09-01
Hypoxia inducible factor-1 (HIF-1) is a transcription factor that is a major regulator of energy homeostasis and cellular adaptation to low oxygen stress. HIF-1 is also activated in response to bacterial pathogens and supports the innate immune response of both phagocytes and keratinocytes. In this work, we show that a new pharmacological compound AKB-4924 increases HIF-1 levels and enhances the antibacterial activity of phagocytes and keratinocytes against both methicillin-sensitive and methicillin-resistant strains of Staphylococcus aureus in vitro. AKB-4924 is also effective in stimulating the killing capacity of keratinocytes against the important opportunistic skin pathogens Pseudomonas aeruginosa and Acinetobacter baumanii. The effect of AKB-4924 is mediated through the activity of host cells, as the compound exerts no direct antimicrobial activity. Administered locally as a single agent, AKB-4924 limits S. aureus proliferation and lesion formation in a mouse skin abscess model. This approach to pharmacologically boost the innate immune response via HIF-1 stabilization may serve as a useful adjunctive treatment for antibiotic-resistant bacterial infections.
Okumura, Cheryl Y.M.; Hollands, Andrew; Tran, Dan N.; Olson, Joshua; Dahesh, Samira; von Köckritz-Blickwede, Maren; Thienphrapa, Wdee; Corle, Courtney; Jeung, Seung Nam; Kotsakis, Anna; Shalwitz, Robert A.; Johnson, Randall S.; Nizet, Victor
2013-01-01
Hypoxia inducible factor-1 (HIF-1) is a transcription factor that is a major regulator of energy homeostasis and cellular adaptation to low oxygen stress. HIF-1 is also activated in response to bacterial pathogens and supports the innate immune response of both phagocytes and keratinocytes. In this work, we show that a new pharmacological compound AKB-4924 (Akebia Therapeutics) increases HIF-1α levels and enhances the antibacterial activity of phagocytes and keratinocytes against both methicillin-sensitive and -resistant strains of Staphylococcus aureus in vitro. AKB-4924 is also effective in stimulating the killing capacity of keratinocytes against the important opportunistic skin pathogens Pseudomonas aeruginosa and Acinitobacter baumanii. The effect of AKB-4924 is mediated through the activity of host cells, as the compound exerts no direct antimicrobial activity. Administered locally as a single agent, AKB-4924 limits S. aureus proliferation and lesion formation in a mouse skin abscess model. This approach to pharmacologically boost the innate immune response via HIF-1 stabilization may serve as a useful adjunctive treatment for antibiotic-resistant bacterial infections. PMID:22371073
Sallander, Marie; Hagberg, Malin; Hedhammar, Ake; Rundgren, Margareta; Lindberg, Jan E
2010-08-01
Our main objective was to obtain baseline data on daily metabolisable energy (ME) intake, activity, and risk factors for obesity in a population of 460 privately owned Swedish dogs in 1999. A previously validated mail-and-telephone questionnaire was used (Sallander et al., 2001a). The dogs were of 124 breeds, 1-3 years old, and had body weights (BW) between 1 and 75kg. The ME intakes of this population could be described with the equation ME(intake) (kilojoules, kJ/d)=554BW(0.66) (r(sp)=0.73, P=0.0001). The energy intake originating from commercial foods was 79% (median, range 45-97). Table foods generally had a higher fat content (median 13g/megajoule, MJ, range 1-122) than commercial foods (median 8g/MJ, range 2-18; P=0.0001). The median energy density was 1603kJ/100g (median; range 1106-2105). Almost all (97%) dogs were taken for walks, and there was a significant difference between the duration of the walks during weekdays and weekends (medians 60 and 90min/d, respectively, P=0.006). Sixty percent of all dogs were trained in activities such as obedience (31%), hunting (27%) or tracking (18%) for a median of 35min/d (range 1-146). The final regression model for obesity included the factors sex, appetite and feeding a home-made diet/table foods. Dogs that were perceived to have good or very good appetite had 3.42-fold greater odds for obesity than individuals with bad or very bad appetite (95% CI 1.19-9.80; P=0.022). Females had 2.17-fold greater odds of being obese than males did (95% CI 1.30-3.70; P=0.003). Also, dogs fed table foods or home-made diets had 2.06-fold greater odds of obesity than those that were not given these food items (95% CI 0.97-4.35; P=0.050). Copyright 2010 Elsevier B.V. All rights reserved.
McNeil, J; Brenner, D R; Courneya, K S; Friedenreich, C M
2017-08-01
Despite the clear health benefits of exercise, exercised-induced weight loss is often less than expected. The term 'exercise energy compensation' is used to define the amount of weight loss below what is expected for the amount of exercise energy expenditure. We examined the dose-response effects of exercise volume on energy compensation in postmenopausal women. Data from Alberta Physical Activity and Breast Cancer Prevention (ALPHA) and Breast Cancer and Exercise Trial in Alberta (BETA) were combined for the present analysis. The ALPHA and BETA trials were two-centred, two-armed, 12-month randomized controlled trials. The ALPHA trial included 160 participants randomized to 225 min per week of aerobic exercise, and the BETA trial randomized 200 participants to each 150 and 300 min per week of aerobic exercise. All participants were aged 50-74 years, moderately inactive (<90 min per week of exercise), had no previous cancer diagnosis and a body mass index between 22 and 40 kg m -2 . Energy compensation was based on changes in body composition (dual-energy X-ray absorptiometry scan) and estimated exercise energy expenditure from completed exercise volume. Associations between Δenergy intake, ΔVO 2peak and Δphysical activity time with energy compensation were assessed. No differences in energy compensation were noted between interventions. However, there were large inter-individual differences in energy compensation between participants; 9.4% experienced body composition changes that were greater than expected based on exercise energy expenditure, 64% experienced some degree of energy compensation and 26.6% experienced weight gain based on exercise energy expenditure. Increases in VO 2peak were associated with reductions in energy compensation (β=-3.44 ml kg -1 min -1 , 95% confidence interval for β=-4.71 to -2.17 ml kg -1 min -1 ; P=0.0001). Large inter-individual differences in energy compensation were noted, despite no differences between activity doses. In addition, increases in VO 2peak were associated with lower energy compensation. Future studies are needed to identify behavioral and metabolic factors that may contribute to this large inter-individual variability in energy compensation.
Transforming Growth Factor β/Activin signaling in neurons increases susceptibility to starvation.
Chng, Wen-Bin Alfred; Koch, Rafael; Li, Xiaoxue; Kondo, Shu; Nagoshi, Emi; Lemaitre, Bruno
2017-01-01
Animals rely on complex signaling network to mobilize its energy stores during starvation. We have previously shown that the sugar-responsive TGFβ/Activin pathway, activated through the TGFβ ligand Dawdle, plays a central role in shaping the post-prandial digestive competence in the Drosophila midgut. Nevertheless, little is known about the TGFβ/Activin signaling in sugar metabolism beyond the midgut. Here, we address the importance of Dawdle (Daw) after carbohydrate ingestion. We found that Daw expression is coupled to dietary glucose through the evolutionarily conserved Mio-Mlx transcriptional complex. In addition, Daw activates the TGFβ/Activin signaling in neuronal populations to regulate triglyceride and glycogen catabolism and energy homeostasis. Loss of those neurons depleted metabolic reserves and rendered flies susceptible to starvation.
Dislocation nucleation from symmetric tilt grain boundaries in body-centered cubic vanadium
NASA Astrophysics Data System (ADS)
Xu, Shuozhi; Su, Yanqing
2018-05-01
We perform molecular dynamics (MD) simulations with two interatomic potentials to study dislocation nucleation from six symmetric tilt grain boundaries (GB) using bicrystal models in body-centered cubic vanadium. The influences of the misorientation angle are explored in the context of activated slip systems, critical resolved shear stress (CRSS), and GB energy. It is found that for four GBs, the activated slip systems are not those with the highest Schmid factor, i.e., the Schmid law breaks down. For all misorientation angles, the bicrystal is associated with a lower CRSS than their single crystalline counterparts. Moreover, the GB energy decreases in compressive loading at the yield point with respect to the undeformed configuration, in contrast to tensile loading.
Plasmon-enhanced solar energy conversion in organic bulk heterojunction photovoltaics
NASA Astrophysics Data System (ADS)
Morfa, Anthony J.; Rowlen, Kathy L.; Reilly, Thomas H.; Romero, Manuel J.; van de Lagemaat, Jao
2008-01-01
Plasmon-active silver nanoparticle layers were included in solution-processed bulk-heterojunction solar cells. Nanoparticle layers were fabricated using vapor-phase deposition on indium tin oxide electrodes. Owing to the increase in optical electrical field inside the photoactive layer, the inclusion of such particle films lead to increased optical absorption and consequently increased photoconversion at solar-conversion relevant wavelengths. The resulting solar energy conversion efficiency for a bulk heterojunction photovoltaic device of poly(3-hexylthiophene)/[6,6]-phenyl C61 butyric acid methyl ester was found to increase from 1.3%±0.2% to 2.2%±0.1% for devices employing thin plasmon-active layers. Based on six measurements, the improvement factor of 1.7 was demonstrated to be statistically significant.
Stoch, G; Ylinen, E E; Birczynski, A; Lalowicz, Z T; Góra-Marek, K; Punkkinen, M
2013-02-01
A new method is introduced for analyzing deuteron spin-lattice relaxation in molecular systems with a broad distribution of activation energies and correlation times. In such samples the magnetization recovery is strongly non-exponential but can be fitted quite accurately by three exponentials. The considered system may consist of molecular groups with different mobility. For each group a Gaussian distribution of the activation energy is introduced. By assuming for every subsystem three parameters: the mean activation energy E(0), the distribution width σ and the pre-exponential factor τ(0) for the Arrhenius equation defining the correlation time, the relaxation rate is calculated for every part of the distribution. Experiment-based limiting values allow the grouping of the rates into three classes. For each class the relaxation rate and weight is calculated and compared with experiment. The parameters E(0), σ and τ(0) are determined iteratively by repeating the whole cycle many times. The temperature dependence of the deuteron relaxation was observed in three samples containing CD(3)OH (200% and 100% loading) and CD(3)OD (200%) in NaX zeolite and analyzed by the described method between 20K and 170K. The obtained parameters, equal for all the three samples, characterize the methyl and hydroxyl mobilities of the methanol molecules at two different locations. Copyright © 2012 Elsevier Inc. All rights reserved.
Entropy-scaling laws for diffusion coefficients in liquid metals under high pressures
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cao, Qi-Long, E-mail: qlcao@mail.ustc.edu.cn; Shao, Ju-Xiang; Wang, Fan-Hou, E-mail: eatonch@gmail.com
2015-04-07
Molecular dynamic simulations on the liquid copper and tungsten are used to investigate the empirical entropy-scaling laws D{sup *}=A exp(BS{sub ex}), proposed independently by Rosenfeld and Dzugutov for diffusion coefficient, under high pressure conditions. We show that the scaling laws hold rather well for them under high pressure conditions. Furthermore, both the original diffusion coefficients and the reduced diffusion coefficients exhibit an Arrhenius relationship D{sub M}=D{sub M}{sup 0} exp(−E{sub M}/K{sub B}T), (M=un,R,D) and the activation energy E{sub M} increases with increasing pressure, the diffusion pre-exponential factors (D{sub R}{sup 0} and D{sub D}{sup 0}) are nearly independent of the pressure and element. Themore » pair correlation entropy, S{sub 2}, depends linearly on the reciprocal temperature S{sub 2}=−E{sub S}/T, and the activation energy, E{sub S}, increases with increasing pressure. In particular, the ratios of the activation energies (E{sub un}, E{sub R}, and E{sub D}) obtained from diffusion coefficients to the activation energy, E{sub S}, obtained from the entropy keep constants in the whole pressure range. Therefore, the entropy-scaling laws for the diffusion coefficients and the Arrhenius law are linked via the temperature dependence of entropy.« less
Mlyniec, A; Ekiert, M; Morawska-Chochol, A; Uhl, T
2016-06-01
In this work, we investigate the influence of the surrounding environment and the initial density on the decomposition kinetics of polylactide (PLA). The decomposition of the amorphous PLA was investigated by means of reactive molecular dynamics simulations. A computational model simulates the decomposition of PLA polymer inside the bulk, due to the assumed lack of removal of reaction products from the polymer matrix. We tracked the temperature dependency of the water and carbon monoxide production to extract the activation energy of thermal decomposition of PLA. We found that an increased density results in decreased activation energy of decomposition by about 50%. Moreover, initiation of decomposition of the amorphous PLA is followed by a rapid decline in activation energy caused by reaction products which accelerates the hydrolysis of esters. The addition of water molecules decreases initial energy of activation as well as accelerates the decomposition process. Additionally, we have investigated the dependency of density on external loading. Comparison of pressures needed to obtain assumed densities shows that this relationship is bilinear and the slope changes around a density equal to 1.3g/cm(3). The conducted analyses provide an insight into the thermal decomposition process of the amorphous phase of PLA, which is particularly susceptible to decomposition in amorphous and semi-crystalline PLA polymers. Copyright © 2016 Elsevier Inc. All rights reserved.
Chagas, Mauro H.; Magalhães, Fabrício A.; Peixoto, Gustavo H. C.; Pereira, Beatriz M.; Andrade, André G. P.; Menzel, Hans-Joachim K.
2016-01-01
ABSTRACT Background Stretching exercises are able to promote adaptations in the muscle-tendon unit (MTU), which can be tested through physiological and biomechanical variables. Identifying the key variables in MTU adaptations is crucial to improvements in training. Objective To perform an exploratory factor analysis (EFA) involving the variables often used to evaluate the response of the MTU to stretching exercises. Method Maximum joint range of motion (ROMMAX), ROM at first sensation of stretching (FSTROM), peak torque (torqueMAX), passive stiffness, normalized stiffness, passive energy, and normalized energy were investigated in 36 participants during passive knee extension on an isokinetic dynamometer. Stiffness and energy values were normalized by the muscle cross-sectional area and their passive mode assured by monitoring the EMG activity. Results EFA revealed two major factors that explained 89.68% of the total variance: 53.13% was explained by the variables torqueMAX, passive stiffness, normalized stiffness, passive energy, and normalized energy, whereas the remaining 36.55% was explained by the variables ROMMAX and FSTROM. Conclusion This result supports the literature wherein two main hypotheses (mechanical and sensory theories) have been suggested to describe the adaptations of the MTU to stretching exercises. Contrary to some studies, in the present investigation torqueMAX was significantly correlated with the variables of the mechanical theory rather than those of the sensory theory. Therefore, a new approach was proposed to explain the behavior of the torqueMAX during stretching exercises. PMID:27437715
Active experiments in the ionosphere and variations of geophysical and meteorological parameters
NASA Astrophysics Data System (ADS)
Sivokon, Vladimir; Cherneva, Nina; Shevtsov, Boris
Energy distribution in ionospheric-magnetospheric relations, as one of the possible external climatological factors, may be traced on the basis of the analysis of natural geophysical phenomena such as ionosphere artificial radio radiation and magnetic storms. Development of magnetic disturbances is, to some extent, associated with current variations in electrojet. In its turn, some technologies are known which may affect electrojet and its characteristics. The method, developed by the authors, is based on a complex comparison of different geophysical fields and allows us to determine the degree of active experiment effect on energy change in ionospheric-magnetospheric relations and to evaluate on this basis the degree of active experiment effect on climate in the ionosphere. Within the framework of RAS Presidium Program Project “Determination of climate-forming characteristic changes on the basis of monitoring of geophysical field variations”, investigations have been carried out, which showed the possibility of ionosphere modification effect on the energy of magnetospheric-ionospheric relations. Evaluation of possible climate changes considering ionospheric-magnetospheric relations has not been previously discussed.
NASA Astrophysics Data System (ADS)
Burtan, Zbigniew
2017-11-01
The current level of rockburst hazard in copper mines of the (LGOM) Legnica- Głogów Copper Belt Area is mostly the consequence of mining-induced seismicity, whilst the majority of rockbursting events registered to date were caused by high-energy tremors. The analysis of seismic readings in recent years reveals that the highest seismic activity among the copper mines in the LGOM is registered in the mine Rudna. This study investigates the seismic activity in the rock strata in the Rudna mine fields over the years 2006-2015. Of particular interest are the key seismicity parameters: the number of registered seismic events, the total energy emissions, the energy index. It appears that varied seismic activity in the area may be the function of several variables: effective mining thickness, the thickness of burst-prone strata and tectonic intensity. The results support and corroborate the view that principal factors influencing the actual seismic hazard level are regional geological conditions in the copper mines within the Legnica-Głogów Copper Belt Area.
Building Energy Model Development for Retrofit Homes
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chasar, David; McIlvaine, Janet; Blanchard, Jeremy
2012-09-30
Based on previous research conducted by Pacific Northwest National Laboratory and Florida Solar Energy Center providing technical assistance to implement 22 deep energy retrofits across the nation, 6 homes were selected in Florida and Texas for detailed post-retrofit energy modeling to assess realized energy savings (Chandra et al, 2012). However, assessing realized savings can be difficult for some homes where pre-retrofit occupancy and energy performance are unknown. Initially, savings had been estimated using a HERS Index comparison for these homes. However, this does not account for confounding factors such as occupancy and weather. This research addresses a method to moremore » reliably assess energy savings achieved in deep energy retrofits for which pre-retrofit utility bills or occupancy information in not available. A metered home, Riverdale, was selected as a test case for development of a modeling procedure to account occupancy and weather factors, potentially creating more accurate estimates of energy savings. This “true up” procedure was developed using Energy Gauge USA software and post-retrofit homeowner information and utility bills. The 12 step process adjusts the post-retrofit modeling results to correlate with post-retrofit utility bills and known occupancy information. The “trued” post retrofit model is then used to estimate pre-retrofit energy consumption by changing the building efficiency characteristics to reflect the pre-retrofit condition, but keeping all weather and occupancy-related factors the same. This creates a pre-retrofit model that is more comparable to the post-retrofit energy use profile and can improve energy savings estimates. For this test case, a home for which pre- and post- retrofit utility bills were available was selected for comparison and assessment of the accuracy of the “true up” procedure. Based on the current method, this procedure is quite time intensive. However, streamlined processing spreadsheets or incorporation into existing software tools would improve the efficiency of the process. Retrofit activity appears to be gaining market share, and this would be a potentially valuable capability with relevance to marketing, program management, and retrofit success metrics.« less
[Energy policy rather than climate policy].
Kroonenberg, Salomon B
2009-01-01
Energy policy and climate policy are two different issues and should not be treated as if they were the same. Whether the climate gets warmer or colder, saving energy and developing sustainable forms of energy production remain of paramount importance because fossil hydrocarbons are likely to be exhausted soon. But climate policy is a fallacy: it is human arrogance to think we can control the climate by reducing emissions and by storing CO2 underground. In spite of rising CO2 levels, the climate has cooled down slightly over the past decade. Since the International Panel on Climate Change (IPCC) did not predict this, it is questionable whether they can reliably predict warming. Other factors such as solar activity are probably more important for climate than greenhouse gases. The danger of coupling energy policy to climate policy is evident: if the climate cools down, people will lose belief in the greenhouse effect and therefore also lose interest in saving energy.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Onar, Omer C; Tang, Lixin; Chinthavali, Madhu Sudhan
2014-01-01
Wireless Power Transfer (WPT) technology is a novel research area in the charging technology that bridges the utility and the automotive industries. There are various solutions that are currently being evaluated by several research teams to find the most efficient way to manage the power flow from the grid to the vehicle energy storage system. There are different control parameters that can be utilized to compensate for the change in the impedance due to variable parameters such as battery state-of-charge, coupling factor, and coil misalignment. This paper presents the implementation of an active front-end rectifier on the grid side formore » power factor control and voltage boost capability for load power regulation. The proposed SiC MOSFET based single phase active front end rectifier with PFC resulted in >97% efficiency at 137mm air-gap and >95% efficiency at 160mm air-gap.« less
Jensen, Jørgen Dejgård; Bere, Elling; De Bourdeaudhuij, Ilse; Jan, Natasa; Maes, Lea; Manios, Yannis; Martens, Marloes K; Molnar, Denes; Moreno, Luis A; Singh, Amika S; te Velde, Saskia; Brug, Johannes
2012-11-21
To date, most research on obesogenic environments facing school children has focused on physical and socio-cultural environments. The role of economic factors has been investigated to a much lesser extent. Our objective was to explore the association of micro-level economic factors and incentives with sports activities and intake of soft drinks and fruit juice in 10-12 year-old school children across Europe, and to explore price sensitivity in children's soft drink consumption and correlates of this price sensitivity. Data for the study originate from a cross-sectional survey undertaken in seven European countries (Belgium, Greece, Hungary, Netherlands, Norway, Slovenia and Spain) in 2010 among 10-12 year-old school children and their parents. In total, 7234 child questionnaires and 6002 parent questionnaires were completed. The child questionnaire included questions addressing self-reported weekly intake of soft drinks and fruit juices and time spent on sports activities, perception of parental support for sports activities, use of pocket money for soft drinks and perceived price responsiveness. Parent questionnaires included questions addressing the role of budget and price considerations in decisions regarding children's sports activities, soft drink consumption, home practices and rules and socio-demographic background variables. Data were analysed using multiple linear regression and discrete-choice (ordered probit) modelling. Economic factors were found to be associated with children's sports participation and sugary drink consumption, explaining 27% of the variation in time for sports activities, and 27% and 12% of the variation in the children's soft drink and juice consumption, respectively. Parents' financial support was found to be an important correlate (Beta =0.419) of children's sports activities. Children's pocket money was a strong correlate (Beta =21.034) of soft drink consumption. The majority of the responding children reported to expect that significantly higher prices of soft drinks would lead them to buy less soft drinks with their own pocket money, but a majority of parents did not expect higher soft drink prices to reduce their children's soft drink consumption. We conclude that economic factors, especially parents' financial support and amount of pocket money, appear to be of importance for children's sports participation and soft drink consumption, respectively.
2012-01-01
Background To date, most research on obesogenic environments facing school children has focused on physical and socio-cultural environments. The role of economic factors has been investigated to a much lesser extent. Our objective was to explore the association of micro-level economic factors and incentives with sports activities and intake of soft drinks and fruit juice in 10-12 year-old school children across Europe, and to explore price sensitivity in children’s soft drink consumption and correlates of this price sensitivity. Methods Data for the study originate from a cross-sectional survey undertaken in seven European countries (Belgium, Greece, Hungary, Netherlands, Norway, Slovenia and Spain) in 2010 among 10-12 year-old school children and their parents. In total, 7234 child questionnaires and 6002 parent questionnaires were completed. The child questionnaire included questions addressing self-reported weekly intake of soft drinks and fruit juices and time spent on sports activities, perception of parental support for sports activities, use of pocket money for soft drinks and perceived price responsiveness. Parent questionnaires included questions addressing the role of budget and price considerations in decisions regarding children’s sports activities, soft drink consumption, home practices and rules and socio-demographic background variables. Data were analysed using multiple linear regression and discrete-choice (ordered probit) modelling. Results Economic factors were found to be associated with children’s sports participation and sugary drink consumption, explaining 27% of the variation in time for sports activities, and 27% and 12% of the variation in the children’s soft drink and juice consumption, respectively. Parents’ financial support was found to be an important correlate (Beta =0.419) of children’s sports activities. Children’s pocket money was a strong correlate (Beta =21.034) of soft drink consumption. The majority of the responding children reported to expect that significantly higher prices of soft drinks would lead them to buy less soft drinks with their own pocket money, but a majority of parents did not expect higher soft drink prices to reduce their children’s soft drink consumption. Conclusions We conclude that economic factors, especially parents’ financial support and amount of pocket money, appear to be of importance for children’s sports participation and soft drink consumption, respectively. PMID:23171289
NASA Astrophysics Data System (ADS)
Stinziano, J. R.; Way, D.; Bauerle, W.
2017-12-01
Photosynthetic temperature acclimation could strongly affect coupled vegetation-atmosphere feedbacks in the global carbon cycle, especially as the climate warms. Thermal acclimation of photosynthesis can be modelled as changes in the parameters describing the direct effect of temperature on photosynthetic capacity (activation energy, Ea; deactivation energy, Hd; entropy parameter, ΔS) or the basal value of photosynthetic capacity (i.e. photosynthetic capacity measured at 25 °C), however the impact of acclimating these parameters (individually or in combination) on vegetative carbon gain is relatively unexplored. Here we compare the ability of 66 photosynthetic temperature acclimation scenarios to improve predictions of a spatially explicit canopy carbon flux model, MAESTRA, for eddy covariance data from a loblolly pine forest. We show that: 1) incorporating seasonal temperature acclimation of basal photosynthetic capacity improves the model's ability to capture seasonal changes in carbon fluxes; 2) multifactor scenarios of photosynthetic temperature acclimation provide minimal (if any) improvement in model performance over single factor acclimation scenarios; 3) acclimation of enzyme activation energies should be restricted to the temperature ranges of the data from which the equations are derived; and 4) model performance is strongly affected by the choice of deactivation energy. We suggest that a renewed effort be made into understanding the thermal acclimation of enzyme activation and deactivation energies across broad temperature ranges to better understand the mechanisms underlying thermal photosynthetic acclimation.
Minakata, Daisuke; Crittenden, John
2011-04-15
The hydroxyl radical (HO(•)) is a strong oxidant that reacts with electron-rich sites on organic compounds and initiates complex radical chain reactions in aqueous phase advanced oxidation processes (AOPs). Computer based kinetic modeling requires a reaction pathway generator and predictions of associated reaction rate constants. Previously, we reported a reaction pathway generator that can enumerate the most important elementary reactions for aliphatic compounds. For the reaction rate constant predictor, we develop linear free energy relationships (LFERs) between aqueous phase literature-reported HO(•) reaction rate constants and theoretically calculated free energies of activation for H-atom abstraction from a C-H bond and HO(•) addition to alkenes. The theoretical method uses ab initio quantum mechanical calculations, Gaussian 1-3, for gas phase reactions and a solvation method, COSMO-RS theory, to estimate the impact of water. Theoretically calculated free energies of activation are found to be within approximately ±3 kcal/mol of experimental values. Considering errors that arise from quantum mechanical calculations and experiments, this should be within the acceptable errors. The established LFERs are used to predict the HO(•) reaction rate constants within a factor of 5 from the experimental values. This approach may be applied to other reaction mechanisms to establish a library of rate constant predictions for kinetic modeling of AOPs.
[Occupational hygiene at solar-energy electric power plants].
Lipkina, L I; Kolesnikova, A V; Tsirkova, N L
1991-01-01
The labour conditions of the personnel engaged in servicing an experimental solar electric power station in warm seasons of the year were characterized by the unfavourable environmental factors peculiar of working out-doors (heliostat sites) and in the station's shops (solar radiation, heating microclimate, noise). Combinations and activity of those factors were professionally determined. Established was the role of the labour conditions and respective occupational peculiarities in the individual response formation to work overload. A set of health-related preventive measures was also proposed.
Energetic constraints on life in deep marine sediments
NASA Astrophysics Data System (ADS)
Amend, J.; LaRowe, D.
2013-12-01
Microorganisms are abundant in deep-sea sediments, but what percentage of cells is active, how fast do they grow, and what factors control their diversity and population size? Geochemical modelling of redox reaction energetics can help in answering these questions. Calculations of Gibbs energies reveal which reactions are thermodynamically possible, but they also highlight which geochemical variables (e.g., temperature, pressure, pH, composition) may control microbial activity and how the amount and type of biomass are affected by energy limitations. We will discuss recent results from sediment cores collected at the Peru Margin (active continental shelf with high primary productivity and significant organic matter accumulation), the South Pacific Gyre (ultra-slow sedimentation rate and low organic carbon content), and the Juan de Fuca Ridge flank (high rate of sedimentation influenced by hydrothermal circulation). However, this approach to evaluating bioenergetic potential and predicting microbial activity can be applied to any environment where the geochemistry is well characterized, even if microbiology data have not been collected. When Gibbs energies are calculated on a basis of per mole of electrons transferred (as is commonly done), aerobic oxidation of hydrogen and organic matter in South Pacific Gyre sediments is the most exergonic. Based on this, one might posit that the fastest catabolic rates and the largest biomass would be found there. However, cell counts at Juan de Fuca and the Peru Margin are several orders of magnitude higher. When recast as energy densities (in J per cm3 of sediment), we observe far more energy available in sediments at Juan de Fuca and the Peru Margin than at those in the South Pacific Gyre. We also note that the identity of the most exergonic reaction changes with depth, suggesting corresponding changes in the microbial community structure. The thermodynamic approach used here for energy supply can also be used for energy demand, including the often-considered minimum or threshold energy, also referred to as the biological energy quantum. Based on this energetic minimum theory, many reactions cannot support microbial communities because their energy yield is apparently too low. However, we show that when evaluated as energy densities, some energetically ';impossible' catabolisms become ';possible' and vice versa.
Air transportation energy efficiency - Alternatives and implications
NASA Technical Reports Server (NTRS)
Williams, L. J.
1976-01-01
Results from recent studies of air transportation energy efficiency alternatives are discussed, along with some of the implications of these alternatives. The fuel-saving alternatives considered include aircraft operation, aircraft modification, derivative aircraft, and new aircraft. In the near-term, energy efficiency improvements should be possible through small improvements in fuel-saving flight procedures, higher density seating, and higher load factors. Additional small near-term improvements could be obtained through aircraft modifications, such as the relatively inexpensive drag reduction modifications. Derivatives of existing aircraft could meet the requirements for new aircraft and provide energy improvements until advanced technology is available to justify the cost of a completely new design. In order to obtain significant improvements in energy efficiency, new aircraft must truly exploit advanced technology in such areas as aerodynamics, composite structures, active controls, and advanced propulsion.
Karpiński, Michał; Popko, Janusz; Maresz, Katarzyna; Badmaev, Vladimir; Stohs, Sidney J
2017-07-01
The research on skeletal system health in children and young adults, while recognizing the important role of calcium and vitamin D, goes beyond these nutritional standards. This review focuses on the role of vitamin K in combination with vitamin D and other factors in bone health. The current understanding is that maintaining bone health and prevention of low-energy fractures in any pediatric population includes nutritional factors combined with an active lifestyle. Calcium, vitamin D, and vitamin K supplementation contribute independently and collectively to bone health. The beneficial role of vitamin K, particularly vitamin K2 as menaquinone-7 (MK-7), in bone and cardiovascular health is reasonably well supported scientifically, with several preclinical, epidemiological, and clinical studies published over the last decade. Osteocalcin and matrix-Gla (glutamate-containing) protein (MGP) exemplify vitamin K-dependent proteins involved in building bone matrix and keeping calcium from accumulating in the arterial walls, respectively. An important part of the mechanism of vitamin K involves carboxylation and posttranslational activation of the family of vitamin K-dependent proteins, which prevent expression of pro-inflammatory factors and support improvement in bone mineral concentration, bone mineral density, and the quality of bone matrix. Understanding the combined approach to a healthy skeletal system in children and young adults, including the roles of vitamins D and K, calcium, healthy diet, and exercise, is particularly important in view of reports of subclinical insufficiency of vitamins D and K in otherwise healthy pediatric populations with low-energy bone fractures.
A proposed model of factors influencing hydrogen fuel cell vehicle acceptance
NASA Astrophysics Data System (ADS)
Imanina, N. H. Noor; Kwe Lu, Tan; Fadhilah, A. R.
2016-03-01
Issues such as environmental problem and energy insecurity keep worsening as a result of energy use from household to huge industries including automotive industry. Recently, a new type of zero emission vehicle, hydrogen fuel cell vehicle (HFCV) has received attention. Although there are argues on the feasibility of hydrogen as the future fuel, there is another important issue, which is the acceptance of HFCV. The study of technology acceptance in the early stage is a vital key for a successful introduction and penetration of a technology. This paper proposes a model of factors influencing green vehicle acceptance, specifically HFCV. This model is built base on two technology acceptance theories and other empirical studies of vehicle acceptance. It aims to provide a base for finding the key factors influencing new sustainable energy fuelled vehicle, HFCV acceptance which is achieved by explaining intention to accept HFCV. Intention is influenced by attitude, subjective norm and perceived behavioural control from Theory of Planned Behaviour and personal norm from Norm Activation Theory. In the framework, attitude is influenced by perceptions of benefits and risks, and social trust. Perceived behavioural control is influenced by government interventions. Personal norm is influenced by outcome efficacy and problem awareness.
Lera Marqués, Lydia; Olivares Cortés, Sonia; Leyton Dinamarca, Bárbara; Bustos Zapata, Nelly
2006-06-01
The aim of the present study was to identify dietary patterns in girls and to assess their association with obesity or overweight. A school-based sample of 108 girls between 8 and 11 years of medium-high socioeconomic level was selected in Santiago, Chile. The body mass index was calculated and a quantified food frequency and physical activity questionnaires (validated in the FAO/MINEDUC/INTA Project Nutritional Education in primary schools) were applied. Four distinct dietary factors or patterns were obtained explaining 54% of the total variation using factorial analysis. The first factor was characterized by an energy-dense diet (high consumption of fat foods, ice creams, chocolates, French fries, snacks). The second factor represented a healthy diet (dairy products, fruits and salads). The third factor represented intake of soft drinks (either with or without sugar). The fourth factor represented a diet rich in calories and sugars (bread, sausages, sweets). The association between the four dietary factors and overweight/obesity was assessed through logistic regression models. The first factor, energy-dense foods, was the only one significantly associated with the presence of obesity (OR = 1.86; 95% CI: 1.12 - 3.09). The results of this research about dietary patterns are consistent with studies carried out in other countries.
Park, Song Yi; Shin, Jee-Hye; Kee, Sun-Ho
2017-09-01
β-Catenin is a central player in Wnt signaling, and activation of Wnt signaling is associated with cancer development. E-cadherin in complex with β-catenin mediates cell-cell adhesion, which suppresses β-catenin-dependent Wnt signaling. Recently, a tumor-suppressive role for E-cadherin has been reconsidered, as re-expression of E-cadherin was reported to enhance the metastatic potential of malignant tumors. To explore the role of E-cadherin, we established an E-cadherin-expressing cell line, EC96, from AGS cells that featured undetectable E-cadherin expression and a high level of Wnt signaling. In EC96 cells, E-cadherin re-expression enhanced cell proliferation, although Wnt signaling activity was reduced. Subsequent analysis revealed that nuclear factor-κB (NF-κB) activation and consequent c-myc expression might be involved in E-cadherin expression-mediated cell proliferation. To facilitate rapid proliferation, EC96 cells enhance glucose uptake and produce ATP using both mitochondria oxidative phosphorylation and glycolysis, whereas AGS cells use these mechanisms less efficiently. These events appeared to be mediated by NF-κB activation. Therefore, E-cadherin re-expression and subsequent induction of NF-κB signaling likely enhance energy production and cell proliferation. © 2017 The Authors. Cancer Science published by John Wiley & Sons Australia, Ltd on behalf of Japanese Cancer Association.
Buffart, Laurien M; Westendorp, Tessa; van den Berg-Emons, Rita J; Stam, Henk J; Roebroeck, Marij E
2009-11-01
To explore the main barriers to and facilitators of physical activity in young adults with childhood-onset physical disabilities. Qualitative study using focus groups. Sixteen persons (12 men and 4 women) aged 22.4 (standard deviation 3.4) years, of whom 50% were wheelchair-dependent, participated in the study. Eight were diagnosed with myelomeningocele, 4 with cerebral palsy, 2 with acquired brain injury and 2 with rheumatoid arthritis. Three focus group sessions of 1.5 h were conducted using a semi-structured question route to assess perceived barriers to and facilitators of physical activity. Tape recordings were transcribed verbatim and content analysed. According to the Physical Activity for People with a Physical Disability model, barriers and facilitators were subdivided into personal factors and environmental factors. Participants reported several barriers related to attitude and motivation. In addition, lack of energy, existing injury or fear of developing injuries or complications, limited physical activity facilities, and lack of information and knowledge, appeared to be barriers to physical activity. Fun and social contacts were mentioned as facilitators of engaging in physical activity, as well as improved health and fitness. Young adults with childhood-onset physical disabilities perceived various personal and environmental factors as barriers to or facilitators of physical activity. These should be taken into account when developing interventions to promote physical activity in this population.
Daily life activity and the risk of developing hypertension in middle-aged Japanese men.
Nakanishi, Noriyuki; Suzuki, Kenji
2005-01-24
Although previous studies suggest that physical activity may reduce the risk of hypertension, the role of daily life activity in the development of hypertension remains unclear. The study population included 2548 Japanese male office workers aged 35 to 59 years, who were without hypertension (systolic blood pressure [SBP] <140 mm Hg, diastolic blood pressure [DBP] <90 mm Hg, and no medication for hypertension) and had no history of cardiovascular disease. Daily life energy expenditure was estimated by a 1-day activity record during an ordinary weekday at study entry. Blood pressures were measured at periodic annual health examinations over 7 successive years. After controlling for potential predictors of hypertension (age, family history of hypertension, alcohol consumption, cigarette smoking, regular physical exercise at entry, and change in body mass index during the follow-up period), mean SBP and DBP in each follow-up year decreased as daily life energy expenditure increased. With additional adjustment for SBP at entry, the relative risk of hypertension (SBP > or =140 mm Hg and/or DBP > or =90 mm Hg or medication for hypertension) across quartiles of daily life energy expenditure (lowest to highest) were 1.00, 0.84, 0.75, and 0.54 (P<.001 for trend). Analyses by presence or absence of a risk factor demonstrated that the risk of hypertension was inversely related to daily life energy expenditure in men at either low or high risk of hypertension. Daily life energy expenditure was also associated with reduced risk of hypertension for subjects in all 3 categories of normotension: low normal, normal, and high normal. Increased daily life activity is effective for the prevention of hypertension, and this benefit applies to men at either low or high risk of hypertension.
A link between hepatic glucose production and peripheral energy metabolism via hepatokines
Abdul-Wahed, Aya; Gautier-Stein, Amandine; Casteras, Sylvie; Soty, Maud; Roussel, Damien; Romestaing, Caroline; Guillou, Hervé; Tourette, Jean-André; Pleche, Nicolas; Zitoun, Carine; Gri, Blandine; Sardella, Anne; Rajas, Fabienne; Mithieux, Gilles
2014-01-01
Type 2 diabetes is characterized by a deterioration of glucose tolerance, which associates insulin resistance of glucose uptake by peripheral tissues and increased endogenous glucose production. Here we report that the specific suppression of hepatic glucose production positively modulates whole-body glucose and energy metabolism. We used mice deficient in liver glucose-6 phosphatase that is mandatory for endogenous glucose production. When they were fed a high fat/high sucrose diet, they resisted the development of diabetes and obesity due to the activation of peripheral glucose metabolism and thermogenesis. This was linked to the secretion of hepatic hormones like fibroblast growth factor 21 and angiopoietin-like factor 6. Interestingly, the deletion of hepatic glucose-6 phosphatase in previously obese and insulin-resistant mice resulted in the rapid restoration of glucose and body weight controls. Therefore, hepatic glucose production is an essential lever for the control of whole-body energy metabolism during the development of obesity and diabetes. PMID:25061558
A link between hepatic glucose production and peripheral energy metabolism via hepatokines.
Abdul-Wahed, Aya; Gautier-Stein, Amandine; Casteras, Sylvie; Soty, Maud; Roussel, Damien; Romestaing, Caroline; Guillou, Hervé; Tourette, Jean-André; Pleche, Nicolas; Zitoun, Carine; Gri, Blandine; Sardella, Anne; Rajas, Fabienne; Mithieux, Gilles
2014-08-01
Type 2 diabetes is characterized by a deterioration of glucose tolerance, which associates insulin resistance of glucose uptake by peripheral tissues and increased endogenous glucose production. Here we report that the specific suppression of hepatic glucose production positively modulates whole-body glucose and energy metabolism. We used mice deficient in liver glucose-6 phosphatase that is mandatory for endogenous glucose production. When they were fed a high fat/high sucrose diet, they resisted the development of diabetes and obesity due to the activation of peripheral glucose metabolism and thermogenesis. This was linked to the secretion of hepatic hormones like fibroblast growth factor 21 and angiopoietin-like factor 6. Interestingly, the deletion of hepatic glucose-6 phosphatase in previously obese and insulin-resistant mice resulted in the rapid restoration of glucose and body weight controls. Therefore, hepatic glucose production is an essential lever for the control of whole-body energy metabolism during the development of obesity and diabetes.
Elbert, Katherine; Hu, Jue; Ma, Zhong; ...
2015-10-05
Hydrogen oxidation and evolution on Pt in acid are facile processes, while in alkaline electrolytes, they are 2 orders of magnitude slower. Thus, developing catalysts that are more active than Pt for these two reactions is important for advancing the performance of anion exchange membrane fuel cells and water electrolyzers. Herein, we detail a 4-fold enhancement of Pt mass activity that we achieved using single-crystalline Ru@Pt core–shell nanoparticles with two-monolayer-thick Pt shells, which doubles the activity on Pt–Ru alloy nanocatalysts. For Pt specific activity, the two- and one-monolayer-thick Pt shells exhibited enhancement factors of 3.1 and 2.3, respectively, compared tomore » the Pt nanocatalysts in base, differing considerably from the values of 1 and 0.4, respectively, in acid. To explain such behavior and the orders of magnitude difference in activity on going from acid to base, we performed kinetic analyses of polarization curves over a wide range of potential from –250 to 250 mV using the dual-pathway kinetic equation. From acid to base, the activation free energies increase the most for the Volmer reaction, resulting in a switch of the rate-determining step from the Tafel to the Volmer reaction, and a shift to a weaker optimal hydrogen binding energy. Furthermore, the much higher activation barrier for the Volmer reaction in base than in acid is ascribed to one or both of the two catalyst-insensitive factors: slower transport of OH – than H + in water and a stronger O–H bond in water molecules (HO–H) than in hydrated protons (H 2O–H +).« less
Fusion energy division annual progress report, period ending December 31, 1980
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1981-11-01
The ORNL Program encompasses most aspects of magnetic fusion research including research on two magnetic confinement programs (tokamaks and ELMO bumpy tori); the development of the essential technologies for plasma heating, fueling, superconducting magnets, and materials; the development of diagnostics; the development of atomic physics and radiation effect data bases; the assessment of the environmental impact of magnetic fusion; the physics and engineering of present-generation devices; and the design of future devices. The integration of all of these activities into one program is a major factor in the success of each activity. An excellent example of this integration is themore » extremely successful application of neutral injection heating systems developed at ORNL to tokamaks both in the Fusion Energy Division and at Princeton Plasma Physics Laboratory (PPPL). The goal of the ORNL Fusion Program is to maintain this balance between plasma confinement, technology, and engineering activities.« less
van Dongen, Joost T; Licausi, Francesco
2015-01-01
Oxygen is an indispensable substrate for many biochemical reactions in plants, including energy metabolism (respiration). Despite its importance, plants lack an active transport mechanism to distribute oxygen to all cells. Therefore, steep oxygen gradients occur within most plant tissues, which can be exacerbated by environmental perturbations that further reduce oxygen availability. Plants possess various responses to cope with spatial and temporal variations in oxygen availability, many of which involve metabolic adaptations to deal with energy crises induced by low oxygen. Responses are induced gradually when oxygen concentrations decrease and are rapidly reversed upon reoxygenation. A direct effect of the oxygen level can be observed in the stability, and thus activity, of various transcription factors that control the expression of hypoxia-induced genes. Additional signaling pathways are activated by the impact of oxygen deficiency on mitochondrial and chloroplast functioning. Here, we describe the molecular components of the oxygen-sensing pathway.
Does Conspecific Fighting Yield Conditioned Taste Aversion in Rats?
ERIC Educational Resources Information Center
Nakajima, Sadahiko; Kumazawa, Gaku; Ieki, Hayato; Hashimoto, Aya
2012-01-01
Running in an activity wheel yields conditioned aversion to a taste solution consumed before the running, but its underlying physiological mechanism is unknown. According to the claim that energy expenditure or general stress caused by physical exercise is a critical factor for this taste-aversion learning, not only running but also other…
Energy Transfer to Upper Trophic Levels on a Small Offshore Bank
2008-01-01
other feeding hotspots in the Gulf of Maine show that they are ephemeral—sometimes very active, often not. Our goals are to understand the factors that...focused on defining patterns of biodiversity in the oceans and the processes that shape them. The Gulf of Maine program has the additional aim of
Neonatal Nutrition Predicts Energy Balance in Young Adults Born Preterm at Very Low Birth Weight
Matinolli, Hanna-Maria; Hovi, Petteri; Levälahti, Esko; Kaseva, Nina; Silveira, Patricia P.; Hemiö, Katri; Järvenpää, Anna-Liisa; Eriksson, Johan G.; Andersson, Sture; Lindström, Jaana; Männistö, Satu; Kajantie, Eero
2017-01-01
Epidemiological studies and animal models suggest that early postnatal nutrition and growth can influence adult health. However, few human studies have objective recordings of early nutrient intake. We studied whether nutrient intake and growth during the first 9 weeks after preterm birth with very low birth weight (VLBW, <1500 g) predict total energy intake, resting energy expenditure (REE), physical activity and food preferences in young adulthood. We collected daily nutritional intakes and weights during the initial hospital stay from hospital records for 127 unimpaired VLBW participants. At an average age 22.5 years, they completed a three-day food record and a physical activity questionnaire and underwent measurements of body composition (dual X-ray absorptiometry; n = 115 with adequate data) and REE (n = 92 with adequate data). We used linear regression and path analysis to investigate associations between neonatal nutrient intake and adult outcomes. Higher energy, protein and fat intakes during the first three weeks of life predicted lower relative (=per unit lean body mass) energy intake and relative REE in adulthood, independent of other pre- and neonatal factors. In path analysis, total effects of early nutrition and growth on relative energy intake were mostly explained by direct effects of early life nutrition. A path mediated by early growth reached statistical significance only for protein intake. There were no associations of neonatal intakes with physical activity or food preferences in adulthood. As a conclusion, higher intake of energy and nutrients during first three weeks of life of VLBW infants predicts energy balance after 20 years. This association is partly mediated through postnatal growth. PMID:29186804
Physical activity and risk of ischemic stroke in the Northern Manhattan Study
Willey, J Z.; Moon, Y P.; Paik, M C.; Boden-Albala, B; Sacco, R L.; Elkind, M S.V.
2009-01-01
Background: It is controversial whether physical activity is protective against first stroke among older persons. We sought to examine whether physical activity, as measured by intensity of exercise and energy expended, is protective against ischemic stroke. Methods: The Northern Manhattan Study is a prospective cohort study in older, urban-dwelling, multiethnic, stroke-free individuals. Baseline measures of leisure-time physical activity were collected via in-person questionnaires. Cox proportional hazards models were constructed to examine whether energy expended and intensity of physical activity were associated with the risk of incident ischemic stroke. Results: Physical inactivity was present in 40.5% of the cohort. Over a median follow-up of 9.1 years, there were 238 incident ischemic strokes. Moderate- to heavy-intensity physical activity was associated with a lower risk of ischemic stroke (adjusted hazard ratio [HR] 0.65, 95% confidence interval [0.44–0.98]). Engaging in any physical activity vs none (adjusted HR 1.16, 95% CI 0.88–1.51) and energy expended in kcal/wk (adjusted HR per 500-unit increase 1.01, 95% CI 0.99–1.03) were not associated with ischemic stroke risk. There was an interaction of sex with intensity of physical activity (p = 0.04), such that moderate to heavy activity was protective against ischemic stroke in men (adjusted HR 0.37, 95% CI 0.18–0.78), but not in women (adjusted HR 0.92, 95% CI 0.57–1.50). Conclusions: Moderate- to heavy-intensity physical activity, but not energy expended, is protective against risk of ischemic stroke independent of other stroke risk factors in men in our cohort. Engaging in moderate to heavy physical activities may be an important component of primary prevention strategies aimed at reducing stroke risk. GLOSSARY CI = confidence interval; HR = hazard ratio; MET = metabolic equivalents. PMID:19933979
NASA Astrophysics Data System (ADS)
Jansen-Glaw, B.; Rössler, E.; Taupitz, M.; Vieth, H. M.
1989-06-01
Deuterated hexamethylbenzene (HMB) is used as a probe molecule for 2H NMR studies of the crystalline state of hexachlorobenzene and of several organic glasses. By measuring the spin-lattice relaxation and the line shape in the temperature range of 4-300 K the dynamical parameters of the molecular reorientation are investigated. For the system HMB/hexachlorobenzene, we find exponential relaxation and for the corresponding T1 an increase of its activation energy by a factor of 2 in comparison to the neat HMB. A homogeneous mixing of the guest and host molecules is found at least for guest concentrations up to 7%. In contrast, nonexponential spin-lattice relaxation is characteristic for all glass matrices, indicating motional heterogeneities. A log-Gauss distribution for the corresponding motional correlation times gives a good fit of the data. Its width parameter decreases linearly with temperature, while the mean correlation times are described by an Arrhenius law. The mean activation energy is reduced by a factor of about 3.5 as compared to neat HMB, demonstrating a loose packing of the molecules in the glass matrices.
Electrical properties of granite with implications for the lower crust.
Olhoeft, G.R.
1981-01-01
The electrical properties of granite appear to be dominantly controlled by the amount of free water in the granite and by temperature. Minor contributions to the electrical properties are provided by hydrostatic and lithostatic pressure, structurally bound water, oxygen fugacity, and other parameters. The effect of sulphur fugacity may be important but is experimentally unconfirmed. In addition to changing the magnitude of electrical properties, the amount and chemistry of water in granite significantly changes the temperature dependence of the electrical properties. With increasing temperature, changes in water content retain large, but lessened, effects on electrical properties. Near room temperature, a monolayer of water will decrease the electrical resistivity by an order of magnitude. Several weight-percent water may decrease the electrical resistivity by as much as nine orders of magnitude and decrease the thermal activation energy by a factor of five. At elevated temperatures just below granitic melting, a few weight-percent water may still decrease the resistivity by as much as 3 orders of magnitude and the activation energy by a factor of two.-Author
NASA Technical Reports Server (NTRS)
Sheng, Y. J.; Wasserburg, G. J.; Hutcheon, I. D.
1992-01-01
An isotopic tracer is used to measure Mg self-diffusion in spinel and coexisting melt at bulk chemical equilibrium. The diffusion coefficients were calculated from the measured isotope profiles using a model that includes the complementary diffusion of Mg-24, Mg-25, and Mg-26 in both phases with the constraint that the Mg content of each phase is constant. The activation energy and preexponential factor for Mg self-diffusion in spinel are, respectively, 384 +/- 7 kJ and 74.6 +/- 1.1 sq cm/s. These data indicate Mg diffusion in spinel is much slower than previous estimates. The activation energy for Mg self-diffusion in coexisting melt is 343 +/- 25 kJ and the preexponential factor is 7791.9 +/- 1.3 sq cm/s. These results are used to evaluate cooling rates of plagioclase-olivine inclusions (POIs) in the Allende meteorite. Given a maximum melting temperature for POIs of about 1500 C, these results show that a 1-micron radius spinel would equilibrate isotopically with a melt within about 60 min.
Kumar, Arvind; Rai, Lal Chand
2015-01-01
Proteomics and biochemical analyses were used to unravel the basis for higher growth yield of Enterobacter sp. LCR1 on insoluble phosphate medium compared to soluble. Proteomic analysis using 2-DE, MALDI-TOF/MS and LC-MS revealed the involvement of nine proteins. Down-regulation of fructose bisphosphate aldolase with decreased concentrations of glucose-6-phosphate and fructose-6-phosphate indicated diminished glycolysis. However, up-regulation of phosphoglycerate mutase, increase in the activities of 6-phosphogluconate dehydratase, 2-keto-3-deoxy-6-phosphogluconate aldolase and 6-phosphogluconate dehydrogenase suggested induction of Entner-Doudoroff and pentose phosphate pathways. These pathways generate sufficient energy from gluconic acid, which is also used for biosynthesis as indicated by up-regulation of elongation factor Tu, elongation factor G and protein disulfide isomerase. Increased reactive oxygen species (ROS) formation resulting from organic acid oxidation leads to overexpressed manganese superoxide dismutase and increased activities of catalase and ascorbate peroxidase. Thus the organism uses gluconate instead of glucose for energy, while alleviating extra ROS formation by oxidative defense enzymes. Copyright © 2014 Elsevier GmbH. All rights reserved.
Marosi, Krisztina; Kim, Sang Woo; Moehl, Keelin; Scheibye-Knudsen, Morten; Cheng, Aiwu; Cutler, Roy; Camandola, Simonetta; Mattson, Mark P
2016-12-01
During fasting and vigorous exercise, a shift of brain cell energy substrate utilization from glucose to the ketone 3-hydroxybutyrate (3OHB) occurs. Studies have shown that 3OHB can protect neurons against excitotoxicity and oxidative stress, but the underlying mechanisms remain unclear. Neurons maintained in the presence of 3OHB exhibited increased oxygen consumption and ATP production, and an elevated NAD + /NADH ratio. We found that 3OHB metabolism increases mitochondrial respiration which drives changes in expression of brain-derived neurotrophic factor (BDNF) in cultured cerebral cortical neurons. The mechanism by which 3OHB induces Bdnf gene expression involves generation of reactive oxygen species, activation of the transcription factor NF-κB, and activity of the histone acetyltransferase p300/EP300. Because BDNF plays important roles in synaptic plasticity and neuronal stress resistance, our findings suggest cellular signaling mechanisms by which 3OHB may mediate adaptive responses of neurons to fasting, exercise, and ketogenic diets. Published 2016. This article is a U.S. Government work and is in the public domain in the USA.
Non-isothermal crystallization kinetics of ternary Se90Te10-xPbx glasses
NASA Astrophysics Data System (ADS)
Atyia, H. E.; Farid, A. S.
2016-02-01
Ternary Se90Te10-xPbx with (x=2 and 6 at%) glass compositions have been prepared using a melt quenching technique and performed the non-isothermal kinetics by differential thermal analysis (DTA) at various heating rates. The glassy state of the studied samples has been characterized using x-ray diffraction analysis. The glass transition temperature Tg, the onset temperature of crystallization Tc and the peak temperature of crystallization Tp are found to be composition and heating rate dependent. From heating rate dependence of Tg and Tp, the glass transition activation energies Eg and the crystallization activation energies Ec have been determined according to different methods. The transformation mechanisms have been examined by the values of Avrami exponent n and dimensionality of growth m. Thermal stability and glass formation ability have been monitored through the calculation of the thermal stability S, temperature difference ΔT, Hurby parameter Hr, frequency factor Ko, crystallization rate factor K and fragility index F. The compositional dependence of the above-mentioned parameters indicate that, the stability of the studied glass samples decreases with increasing Pb at% content.
Meng, X; Kerr, D A; Zhu, K; Devine, A; Solah, V A; Wright, J; Binns, C W; Prince, R L
2013-02-01
Identify the extent of under-reporting of energy intake and the characteristics associated with implausible intakes in elderly women. Dietary intake was assessed using a 3-day weighed food record. Protein intake was validated by 24-hour urinary nitrogen. To examine under-reporting, participants were grouped according to their energy intake and compared to the Goldberg cut-off equation. Logistic regression was performed to assess the influence of body mass index (BMI) and social-demographic factors on under-reporting. Community dwelling elderly women from Perth, Western Australia. 217 elderly women aged 70-80 years. Under-reporters had a higher physical activity level (p<0.001) compared with acceptable-reporters. The under-reporters also had a higher body weight (p=0.006), body mass index (BMI) (p=0.001), waist (p=0.011), hip circumference (p<0.001), whole body fat mass (p<0.001) and percentage body fat (p<0.001) than acceptable-reporters. Under-reporters had a significantly lower intakes of protein, fat, carbohydrate and alcohol (p<0.001) and fewer reported food items, compared with acceptable reporters. However, 24-hour urinary nitrogen was only marginally different between the two groups (p=0.053). Participants with a higher BMI were more likely to under-report their energy intake (BMI=25-29.9: odds ratio=2.98[95% CI=1.46-6.09]; BMI≥30: 5.84[2.41-14.14]). Under-reporting energy intake in elderly women was associated with a higher BMI, body fat and higher self-reported physical activity levels. A higher BMI (≥25) appears to be most significant factor in determining if elderly women will underreport their food intake and may be related to body image. These results have implications for undertaking surveys of food intake in elderly women.
Contact activation of blood-plasma coagulation
NASA Astrophysics Data System (ADS)
Golas, Avantika
Surface engineering of biomaterials with improved hemocompatibility is an imperative, given the widespread global need for cardiovascular devices. Research summarized in this dissertation focuses on contact activation of FXII in buffer and blood plasma frequently referred to as autoactivation. The extant theory of contact activation imparts FXII autoactivation ability to negatively charged, hydrophilic surfaces. According to this theory, contact activation of plasma involves assembly of proteins comprising an "activation complex" on activating surfaces mediated by specific chemical interactions between complex proteins and the surface. This work has made key discoveries that significantly improve our core understanding of contact activation and unravel the existing paradigm of plasma coagulation. It is shown herein that contact activation of blood factor XII (FXII, Hageman factor) in neat-buffer solution exhibits a parabolic profile when scaled as a function of silanized-glass-particle activator surface energy (measured as advancing water adhesion tension t°a=g° Iv costheta in dyne/cm, where g°Iv is water interfacial tension in dyne/cm and theta is the advancing contact angle). Nearly equal activation is observed at the extremes of activator water-wetting properties --36 < t°a < 72 dyne/cm (O° ≤ theta < 120°), falling sharply through a broad minimum within the 20 < t°a < 40 dyne/cm (55° < theta < 75°). Furthermore, contact activation of FXII in buffer solution produces an ensemble of protein fragments exhibiting either procoagulant properties in plasma (proteolysis of blood factor XI or prekallikrein), amidolytic properties (cleavage of s-2302 chromogen), or the ability to suppress autoactivation through currently unknown biochemistry. The relative proportions of these fragments depend on activator surface chemistry/energy. We have also discovered that contact activation is moderated by adsorption of plasma proteins unrelated to coagulation through an "adsorption-dilution" effect that blocks FXII contact with hydrophobic activator surfaces. The adsorption-dilution effect explains the apparent specificity for hydrophilic activators pursued by earlier investigators. Finally a comparison of FXII autoactivation in buffer, serum, protein cocktail, and plasma solutions is shown herein. Activation of blood plasma coagulation in vitro by contact with material surfaces is demonstrably dependent on plasma-volume-to-activator-surface-area ratio. However, activation of factor XII dissolved in buffer, protein cocktail, heat-denatured serum, and FXI deficient plasma does not exhibit activator surface-area dependence. Instead, a highly-variable burst of procoagulant-enzyme yield is measured that exhibits no measurable kinetics, sensitivity to mixing, or solution-temperature dependence. Thus, FXII activation in both buffer and protein-containing solutions does not exhibit characteristics of a biochemical reaction but rather appears to be a "mechanochemical" reaction induced by FXII molecule interactions with hydrophilic activator particles that do not formally adsorb blood proteins from solution. Results strongly suggest that activator surface-area dependence observed in contact activation of plasma coagulation does not solely arise at the FXII activation step of the intrinsic pathway.
The BOLD signal and neurovascular coupling in autism.
Reynell, Clare; Harris, Julia J
2013-10-01
BOLD (blood oxygen level dependent) fMRI (functional magnetic resonance imaging) is commonly used to study differences in neuronal activity between human populations. As the BOLD response is an indirect measure of neuronal activity, meaningful interpretation of differences in BOLD responses between groups relies upon a stable relationship existing between neuronal activity and the BOLD response across these groups. However, this relationship can be altered by changes in neurovascular coupling or energy consumption, which would lead to problems in identifying differences in neuronal activity. In this review, we focus on fMRI studies of people with autism, and comparisons that are made of their BOLD responses with those of control groups. We examine neurophysiological differences in autism that may alter neurovascular coupling or energy use, discuss recent studies that have used fMRI to identify differences between participants with autism and control participants, and explore experimental approaches that could help attribute between-group differences in BOLD signals to either neuronal or neurovascular factors. Copyright © 2013 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Wu, Yunxia; Xing, Da; Chen, Qun; Chen, Tongsheng; Tang, Yonghong; Wan, Qingling
2005-04-01
Apoptosis is one of the important modes in PDT-induced cell death. Activation of caspase-3 is considered to be the final step in many apoptosis pathways. In this study, we used SCAT3, a fluorescence resonance energy transfer (FRET) probe containing caspase-3 substrate, to study the dynamics of caspase-3 activation in living ASTC-a-1 cells expressing stably SCAT3. The FRET analysis results indicated that caspase-3 activation in response to tumor necrosis factor-α or PDT resulted in cleavage of the linker peptide and subsequent disruption of the FRET signal. The SCAT3 was cleaved immediately after PDT treatment, but that for TNF-a treatment was delayed two hours. Our experimental results suggested that the different apoptotic pathways induced by TNF-α or PDT caused different cleavage kinetics of SCAT3. This study shows that FRET technique based on GFPs could be used to study the mechanism of PDT-induced apoptosis in living cells.
Modulation of PPAR Expression and Activity in Response to Polyphenolic Compounds in High Fat Diets
Domínguez-Avila, J. Abraham; González-Aguilar, Gustavo A.; Alvarez-Parrilla, Emilio; de la Rosa, Laura A.
2016-01-01
Peroxisome proliferator-activated receptors (PPAR) are transcription factors that modulate energy metabolism in liver, adipose tissue and muscle. High fat diets (HFD) can negatively impact PPAR expression or activity, favoring obesity, dyslipidemia, insulin resistance and other conditions. However, polyphenols (PP) found in vegetable foodstuffs are capable of positively modulating this pathway. We therefore focused this review on the possible effects that PP can have on PPAR when administered together with HFD. We found that PP from diverse sources, such as coffee, olives, rice, berries and others, are capable of inducing the expression of genes involved in a decrease of adipose mass, liver and serum lipids and lipid biosynthesis in animal and cell models of HFD. Since cells or gut bacteria can transform PP into different metabolites, it is possible that a synergistic or antagonistic effect ultimately occurs. PP molecules from vegetable sources are an interesting option to maintain or return to a state of energy homeostasis, possibly due to an adequate PPAR expression and activity. PMID:27367676
Huy, Ngo Quang; Binh, Do Quang
2014-12-01
This work suggests a method for determining the activities of cylindrical radioactive samples. The self-attenuation factor was applied for providing the self-absorption correction of gamma rays in the sample material. The experimental measurement of a (238)U reference sample and the calculation using the MCNP5 code allow obtaining the semi-empirical formulae of detecting efficiencies for the gamma energies ranged from 185 to 1764keV. These formulae were used to determine the activities of the (238)U, (226)Ra, (232)Th, (137)Cs and (40)K nuclides in the IAEA RGU-1, IAEA-434, IAEA RGTh-1, IAEA-152 and IAEA RGK-1 radioactive standards. The coincidence summing corrections for gamma rays in the (238)U and (232)Th series were applied. The activities obtained in this work were in good agreement with the reference values. Copyright © 2014 Elsevier Ltd. All rights reserved.
The BOLD signal and neurovascular coupling in autism
Reynell, Clare; Harris, Julia J.
2013-01-01
BOLD (blood oxygen level dependent) fMRI (functional magnetic resonance imaging) is commonly used to study differences in neuronal activity between human populations. As the BOLD response is an indirect measure of neuronal activity, meaningful interpretation of differences in BOLD responses between groups relies upon a stable relationship existing between neuronal activity and the BOLD response across these groups. However, this relationship can be altered by changes in neurovascular coupling or energy consumption, which would lead to problems in identifying differences in neuronal activity. In this review, we focus on fMRI studies of people with autism, and comparisons that are made of their BOLD responses with those of control groups. We examine neurophysiological differences in autism that may alter neurovascular coupling or energy use, discuss recent studies that have used fMRI to identify differences between participants with autism and control participants, and explore experimental approaches that could help attribute between-group differences in BOLD signals to either neuronal or neurovascular factors. PMID:23917518
Wang, Chia-Woei; Hsu, Wei-Hsuan; Tai, Chen-Jei
2017-01-01
Cordycepin (3′-deoxyadenosine) is a compound for antitumor, which has been found to exert antiangiogenic, antimetastatic, and antiproliferative effects, as well as inducing apoptosis. However, the association between cancer metastasis and mitochondrial activity in cordycepin-treated ovarian carcinoma cells remains unclear. The 50 and 100 μM of cordycepin inhibits mitochondrial fusion and induces mitochondrial fission, respectively. These suggested that cordycepin showed the down-regulation of mitochondrial function and limitation of energy production. Because of activation of mitochondria and generation of energy are needed in cancer cell migration/invasion. After 24 h treatment, cordycepin suppresses epithelial–mesenchymal transition and migration in ovarian carcinoma cells through inhibiting estrogen-related receptor (ERR)-α. The ERRα is a co-transcription factor for gene expressions associated with mitochondrial fusion. Our results indicate that cordycepin suppresses metastasis and migration of ovarian carcinoma cells via inhibiting mitochondrial activity in non-toxic concentrations, and cordycepin has potential benefits in ovarian cancer therapy. PMID:27966445
Modulation of PPAR Expression and Activity in Response to Polyphenolic Compounds in High Fat Diets.
Domínguez-Avila, J Abraham; González-Aguilar, Gustavo A; Alvarez-Parrilla, Emilio; de la Rosa, Laura A
2016-06-29
Peroxisome proliferator-activated receptors (PPAR) are transcription factors that modulate energy metabolism in liver, adipose tissue and muscle. High fat diets (HFD) can negatively impact PPAR expression or activity, favoring obesity, dyslipidemia, insulin resistance and other conditions. However, polyphenols (PP) found in vegetable foodstuffs are capable of positively modulating this pathway. We therefore focused this review on the possible effects that PP can have on PPAR when administered together with HFD. We found that PP from diverse sources, such as coffee, olives, rice, berries and others, are capable of inducing the expression of genes involved in a decrease of adipose mass, liver and serum lipids and lipid biosynthesis in animal and cell models of HFD. Since cells or gut bacteria can transform PP into different metabolites, it is possible that a synergistic or antagonistic effect ultimately occurs. PP molecules from vegetable sources are an interesting option to maintain or return to a state of energy homeostasis, possibly due to an adequate PPAR expression and activity.
Mitochondrial ROS regulate thermogenic energy expenditure and sulfenylation of UCP1
Chouchani, Edward T.; Kazak, Lawrence; Jedrychowski, Mark P.; Lu, Gina Z.; Erickson, Brian K.; Szpyt, John; Pierce, Kerry A.; Laznik-Bogoslavski, Dina; Vetrivelan, Ramalingam; Clish, Clary B.; Robinson, Alan J.; Gygi, Steve P.; Spiegelman, Bruce M.
2017-01-01
Brown adipose tissue (BAT) can dissipate chemical energy as heat through thermogenic respiration, which requires uncoupling protein 1 (UCP1)1,2. Thermogenesis from BAT and beige adipose can combat obesity and diabetes3, encouraging investigation of factors that control UCP1-dependent respiration in vivo. Herein we show that acutely activated BAT thermogenesis is defined by a substantial increase in mitochondrial reactive oxygen species (ROS) levels. Remarkably, this process supports in vivo BAT thermogenesis, as pharmacological depletion of mitochondrial ROS results in hypothermia upon cold exposure, and inhibits UCP1-dependent increases in whole body energy expenditure. We further establish that thermogenic ROS alter BAT cysteine thiol redox status to drive increased respiration, and Cys253 of UCP1 is a key target. UCP1 Cys253 is sulfenylated during thermogenesis, while mutation of this site desensitizes the purine nucleotide inhibited state of the carrier to adrenergic activation and uncoupling. These studies identify BAT mitochondrial ROS induction as a mechanism that drives UCP1-dependent thermogenesis and whole body energy expenditure, which opens the way to develop improved therapeutic strategies for combating metabolic disorders. PMID:27027295
2012-01-01
Background Choice promotes the experience of autonomy, which enhances intrinsic motivation. Providing a greater choice of traditional active toys may increase children's activity time. Mastery also increases intrinsic motivation and is designed into exergames, which may increase play time of a single exergame, reducing the need for choice to motivate activity compared to traditional active toys. Providing both choice and mastery could be most efficacious at increasing activity time. The energy expenditure (EE) of an active play session is dependent on the duration of play and the rate of EE during play. The rate of EE of exergames and the same game played in traditional fashion is not known. The purpose was to test the basic parameters of choice and mastery on children's physical activity time, activity intensity, and energy expenditure. Methods 44 children were assigned to low (1 toy) or high (3 toys) choice groups. Children completed 60 min sessions with access to traditional active toys on one visit and exergame versions of the same active toys on another visit. Results Choice had a greater effect on increasing girls' (146%) than boys' (23%) activity time and on girls' (230%) than boys' (minus 24%) activity intensity. When provided choice, girls' activity time and intensity were no longer lower than boys' activity time and intensity. The combination of choice and mastery by providing access to 3 exergames produced greater increases in physical activity time (1 toy 22.5 min, 3 toys 41.4 min) than choice alone via access to 3 traditional games (1 toy 13.6 min, 3 toys 19.5 min). Energy expenditure was 83% greater when engaging in traditional games than exergames. Conclusions Boys and girls differ in their behavioral responses to autonomy supportive environments. By providing girls with greater autonomy they can be motivated to engage in physical activity equal to boys. An environment that provides both autonomy and mastery is most efficacious at increasing physical activity time. Though children play exergames 87% longer than traditional games, the rate of energy expenditure is 83% lower for exergames than traditional indoor versions of the same games. PMID:22353207
Roemmich, James N; Lambiase Ms, Maya J; McCarthy, Thomas F; Feda, Denise M; Kozlowski, Karl F
2012-02-21
Choice promotes the experience of autonomy, which enhances intrinsic motivation. Providing a greater choice of traditional active toys may increase children's activity time. Mastery also increases intrinsic motivation and is designed into exergames, which may increase play time of a single exergame, reducing the need for choice to motivate activity compared to traditional active toys. Providing both choice and mastery could be most efficacious at increasing activity time. The energy expenditure (EE) of an active play session is dependent on the duration of play and the rate of EE during play. The rate of EE of exergames and the same game played in traditional fashion is not known. The purpose was to test the basic parameters of choice and mastery on children's physical activity time, activity intensity, and energy expenditure. 44 children were assigned to low (1 toy) or high (3 toys) choice groups. Children completed 60 min sessions with access to traditional active toys on one visit and exergame versions of the same active toys on another visit. Choice had a greater effect on increasing girls' (146%) than boys' (23%) activity time and on girls' (230%) than boys' (minus 24%) activity intensity. When provided choice, girls' activity time and intensity were no longer lower than boys' activity time and intensity. The combination of choice and mastery by providing access to 3 exergames produced greater increases in physical activity time (1 toy 22.5 min, 3 toys 41.4 min) than choice alone via access to 3 traditional games (1 toy 13.6 min, 3 toys 19.5 min). Energy expenditure was 83% greater when engaging in traditional games than exergames. Boys and girls differ in their behavioral responses to autonomy supportive environments. By providing girls with greater autonomy they can be motivated to engage in physical activity equal to boys. An environment that provides both autonomy and mastery is most efficacious at increasing physical activity time. Though children play exergames 87% longer than traditional games, the rate of energy expenditure is 83% lower for exergames than traditional indoor versions of the same games.
Factors associated with bone turnover and speed of sound in early and late-pubertal females.
Klentrou, Panagiota; Ludwa, Izabella A; Falk, Bareket
2011-10-01
This cross-sectional study examines whether maturity, body composition, physical activity, dietary intake, and hormonal concentrations are related to markers of bone turnover and tibial speed of sound (tSOS) in premenarcheal (n = 20, 10.1 ± 1.1 years) and postmenarcheal girls (n = 28, aged 15.0 ± 1.4 years). Somatic maturity was evaluated using years from age of peak height velocity (aPHV). Daily dietary intake was assessed with a 24-h recall interview, and moderate to very vigorous physical activity (MVPA) was measured using accelerometry. Plasma levels of 25-OH vitamin D, serum levels of insulin-like growth-factor 1 (IGF-1) and leptin, and serum levels of bone turnover markers including osteocalcin (OC), bone-specific alkaline phosphatase (BAP) and cross-linked N-teleopeptide of type I collagen (NTX) were measured using ELISA. OC, BAP, and NTX were significantly higher while IGF-1 and tSOS were lower in the premenarcheal group. The premenarcheal girls were more active and had higher daily energy intake relative to their body mass but there were no group differences in body mass index percentile. Maturity predicted 40%-57% of the variance in bone turnover markers. Additionally, daily energy intake was a significant predictor of OC, especially in the postmenarcheal group. IGF-1 and MVPA were significant predictors of BAP in the group as a whole. However, examined separately, IGF-1 was a predictor of BAP in the premenarcheal group while MVPA was a predictor in the postmenarcheal group. Adiposity and leptin were both negative predictors of tSOS, with leptin being specifically predictive in the postmenarcheal group. In conclusion, while maturity was the strongest predictor of bone markers and tSOS, dietary intake, physical activity, body composition, and hormonal factors further contribute to the variance in bone turnover and bone SOS in young Caucasian females. Further, the predicting factors of bone turnover and tSOS were different within each maturity group.
Hydraulic conductivity of fly ash-sewage sludge mixes for use in landfill cover liners.
Herrmann, Inga; Svensson, Malin; Ecke, Holger; Kumpiene, Jurate; Maurice, Christian; Andreas, Lale; Lagerkvist, Anders
2009-08-01
Secondary materials could help meeting the increasing demand of landfill cover liner materials. In this study, the effect of compaction energy, water content, ash ratio, freezing, drying and biological activity on the hydraulic conductivity of two fly ash-sewage sludge mixes was investigated using a 2(7-1) fractional factorial design. The aim was to identify the factors that influence hydraulic conductivity, to quantify their effects and to assess how a sufficiently low hydraulic conductivity can be achieved. The factors compaction energy and drying, as well as the factor interactions material x ash ratio and ash ratio x compaction energy affected hydraulic conductivity significantly (alpha=0.05). Freezing on five freeze-thaw cycles did not affect hydraulic conductivity. Water content affected hydraulic conductivity only initially. The hydraulic conductivity data were modelled using multiple linear regression. The derived models were reliable as indicated by R(adjusted)(2) values between 0.75 and 0.86. Independent on the ash ratio and the material, hydraulic conductivity was predicted to be between 1.7 x 10(-11)m s(-1) and 8.9 x 10(-10)m s(-1) if the compaction energy was 2.4 J cm(-3), the ash ratio between 20% and 75% and drying did not occur. Thus, the investigated materials met the limit value for non-hazardous waste landfills of 10(-9)m s(-1).
Straub, Rainer H
2014-09-01
Chronic inflammatory diseases are accompanied by a systemic response of the body, necessary to redirect energy-rich fuels to the activated immune system and to induce volume expansion. The systemic response is switched on by two major pathways: (a) circulating cytokines enter the brain, and (b) signals via sensory nerve fibers are transmitted to the brain. Concerning item b, sensory nerve terminals are equipped with a multitude of receptors that sense temperature, inflammation, osmolality, and pain. Thus, they can be important to inform the brain about peripheral inflammation. Central to these sensory modalities are transient receptor potential channels (TRP channels) on sensory nerve endings. For example, TRP vanilloid 1 (TRPV1) can be activated by heat, inflammatory factors (e.g., protons, bradykinin, anandamide), hyperosmolality, pungent irritants, and others. TRP channels are multimodal switches that transmit peripheral signals to the brain, thereby inducing a systemic response. It is demonstrated how and why these TRP channels (TRPV1, TRP ankyrin type 1 (TRPA1), and TRP melastatin type 8 (TRPM8)) are important to start up a systemic response of energy expenditure, energy allocation, and water retention and how this is linked to a continuously activated immune system in chronic inflammatory diseases.
Solís-Calero, Christian; Carvalho, Hernandes F
2017-11-01
Kallikrein 14 (KLK14) is a serine protease linked to several pathologies including prostate cancer and positively correlates with Gleason score. Though KLK14 functioning in cancer is poorly understood, it has been implicated in HGF/Met signaling, given that KLK14 proteolytically inhibits HGF activator-inhibitor 1 (HAI-1), which strongly inhibits pro-HGF activators, thereby contributing to tumor progression. In this work, KLK14 binding to either hepatocyte growth factor activator inhibitor type-1 (HAI-1) or type-2 (HAI-2) was essayed using homology modeling, molecular dynamic simulations and free-energy calculations through MM/PBSA and MM/GBSA. KLK14 was successfully modeled. Calculated free energies suggested higher binding affinity for the KLK14/HAI-1 interaction than for KLK14/HAI-2. This difference in binding affinity is largely explained by the higher stability of the hydrogen-bond networks in KLK14/HAI-1 along the simulation trajectory. A key arginine residue in both HAI-1 and HAI-2 is responsible for their interaction with the S1 pocket in KLK14. Additionally, MM/GBSA free-energy decomposition postulates that KLK14 Asp174 and Trp196 are hotspots for binding HAI-1 and HAI-2. © 2017 International Federation for Cell Biology.
Vuković, Lela; Chipot, Christophe; Makino, Debora L; Conti, Elena; Schulten, Klaus
2016-03-30
Recent experimental studies revealed structural details of 3' to 5' degradation of RNA molecules, performed by the exosome complex. ssRNA is channeled through its multisubunit ring-like core into the active site tunnel of its key exonuclease subunit Rrp44, which acts both as an enzyme and a motor. Even in isolation, Rrp44 can pull and sequentially cleave RNA nucleotides, one at a time, without any external energy input and release a final 3-5 nucleotide long product. Using molecular dynamics simulations, we identify the main factors that control these processes. Our free energy calculations reveal that RNA transfer from solution into the active site of Rrp44 is highly favorable, but dependent on the length of the RNA strand. While RNA strands formed by 5 nucleotides or more correspond to a decreasing free energy along the translocation coordinate toward the cleavage site, a 4-nucleotide RNA experiences a free energy barrier along the same direction, potentially leading to incomplete cleavage of ssRNA and the release of short (3-5) nucleotide products. We provide new insight into how Rrp44 catalyzes a localized enzymatic reaction and performs an action distributed over several RNA nucleotides, leading eventually to the translocation of whole RNA segments into the position suitable for cleavage.
Quantum dynamics of hydrogen atoms on graphene. II. Sticking.
Bonfanti, Matteo; Jackson, Bret; Hughes, Keith H; Burghardt, Irene; Martinazzo, Rocco
2015-09-28
Following our recent system-bath modeling of the interaction between a hydrogen atom and a graphene surface [Bonfanti et al., J. Chem. Phys. 143, 124703 (2015)], we present the results of converged quantum scattering calculations on the activated sticking dynamics. The focus of this study is the collinear scattering on a surface at zero temperature, which is treated with high-dimensional wavepacket propagations with the multi-configuration time-dependent Hartree method. At low collision energies, barrier-crossing dominates the sticking and any projectile that overcomes the barrier gets trapped in the chemisorption well. However, at high collision energies, energy transfer to the surface is a limiting factor, and fast H atoms hardly dissipate their excess energy and stick on the surface. As a consequence, the sticking coefficient is maximum (∼0.65) at an energy which is about one and half larger than the barrier height. Comparison of the results with classical and quasi-classical calculations shows that quantum fluctuations of the lattice play a primary role in the dynamics. A simple impulsive model describing the collision of a classical projectile with a quantum surface is developed which reproduces the quantum results remarkably well for all but the lowest energies, thereby capturing the essential physics of the activated sticking dynamics investigated.
Quantum dynamics of hydrogen atoms on graphene. II. Sticking
NASA Astrophysics Data System (ADS)
Bonfanti, Matteo; Jackson, Bret; Hughes, Keith H.; Burghardt, Irene; Martinazzo, Rocco
2015-09-01
Following our recent system-bath modeling of the interaction between a hydrogen atom and a graphene surface [Bonfanti et al., J. Chem. Phys. 143, 124703 (2015)], we present the results of converged quantum scattering calculations on the activated sticking dynamics. The focus of this study is the collinear scattering on a surface at zero temperature, which is treated with high-dimensional wavepacket propagations with the multi-configuration time-dependent Hartree method. At low collision energies, barrier-crossing dominates the sticking and any projectile that overcomes the barrier gets trapped in the chemisorption well. However, at high collision energies, energy transfer to the surface is a limiting factor, and fast H atoms hardly dissipate their excess energy and stick on the surface. As a consequence, the sticking coefficient is maximum (˜0.65) at an energy which is about one and half larger than the barrier height. Comparison of the results with classical and quasi-classical calculations shows that quantum fluctuations of the lattice play a primary role in the dynamics. A simple impulsive model describing the collision of a classical projectile with a quantum surface is developed which reproduces the quantum results remarkably well for all but the lowest energies, thereby capturing the essential physics of the activated sticking dynamics investigated.
[Current concepts of digestion and absorption of carbohydrates].
Luz, S dos S; de Campos, P L; Ribeiro, S M; Tirapegui, J
1997-01-01
The aim of this paper is to review recent aspects of digestion and absorption of carbohydrates that are the main source of energy in human diets. Recent researches have found that starch is not largely hydrolysed and absorbed in the small bowel but one part of it is resistant to digestion. Several food factors may be responsible for digestion and absorption velocity and totality of carbohydrates. Therefore, carbohydrate classification must be based not only on molecular size to express the real carbohydrates utilization as an energy source by humans. In agreement with molecular size of carbohydrate, its classification can be: a) monosaccharides; b) disaccharides; c) oligosaccharides; d) polysaccharides. In agreement with carbohydrate digestibility or availability, its classification can be: a) digestible carbohydrates; b) undigestable carbohydrates (NSP). Carbohydrate digestibility can be altered by several factors like: Intrinsic factors: a) physical structure; b) molecular physical distribution; c) physical state of food; d) food antinutrients. Extrinsics factors: a) chewing; b) transit time of food; c) amount of starch present; d) diet antinutrients. Under influence of this factors, process of digestion happen by enzymatic activity a long the gastrointestinal tract. Salivary and pancreatic amylase; glycosidases of the duodenal enterocyte brush border (lactase, sacarase and maltase), whose activity happen by close interaction of digestive breakdown with transport. The summarized pathways of the absorptive process: 1. movement from the bulk phase of the lumenal or mucosal fluid to enterocyte surface; 2. movement across the brush border membrane through specific transporters: a) SGLT1; b) GLUT 5; c) passive diffusion. 3. movement across the basolateral membrane by the GLUT 2.
Dynamic Pulse-Driven Flowering Phenology in a Semiarid Shrubland
NASA Astrophysics Data System (ADS)
Krell, N.; Papuga, S. A.; Kipnis, E. L.; Nelson, K.
2014-12-01
Elevated springtime temperature has been convincingly linked to an increasingly earlier onset of phenological activity. Studies highlighting this phenomenon have generally been conducted in ecosystems where energy is the primary limiting factor. Importantly, phenological studies in semiarid ecosystems where water is the major limiting factor are rare. In semiarid ecosystems, the timing of phenological activity is also highly sensitive to discrete moisture pulses from infrequent precipitation events. The objective of this study is to identify the triggers of flowering phenology in a semiarid creosotebush-dominated ecosystem. Creosotebush (Larrea tridentata) is a repeat-flowering evergreen shrub that is the dominant species in three of the North American deserts. We present results from six years of daily meteorological and phenological data collected within the Santa Rita Experimental Range in southern Arizona. Our site is equipped with an eddy covariance tower providing estimates of water and carbon fluxes and associated meteorological variables including precipitation and soil moisture at multiple depths. Additionally, three digital cameras distributed within the footprint of the eddy provide daily images of phenological activity. Our results highlight substantial interannual variability in flowering phenology, both in spring and summer flowering. We show that spring flowering activity tends to be associated with energy triggers (e.g. temperature, growing degree days), whereas summer flowering activity tends to be associated with moisture triggers (e.g. large precipitation events, deep soil moisture). Our study suggests that changes in frequency and duration of precipitation events will impact timing of phenological activity resulting in important consequences for vegetation dynamics and pollinator behavior.
Descriptors of Oxygen-Evolution Activity for Oxides: A Statistical Evaluation
Hong, Wesley T.; Welsch, Roy E.; Shao-Horn, Yang
2015-12-16
Catalysts for oxygen electrochemical processes are critical for the commercial viability of renewable energy storage and conversion devices such as fuel cells, artificial photosynthesis, and metal-air batteries. Transition metal oxides are an excellent system for developing scalable, non-noble-metal-based catalysts, especially for the oxygen evolution reaction (OER). Central to the rational design of novel catalysts is the development of quantitative structure-activity relation-ships, which correlate the desired catalytic behavior to structural and/or elemental descriptors of materials. The ultimate goal is to use these relationships to guide materials design. In this study, 101 intrinsic OER activities of 51 perovskites were compiled from fivemore » studies in literature and additional measurements made for this work. We explored the behavior and performance of 14 descriptors of the metal-oxygen bond strength using a number of statistical approaches, including factor analysis and linear regression models. We found that these descriptors can be classified into five descriptor families and identify electron occupancy and metal-oxygen covalency as the dominant influences on the OER activity. However, multiple descriptors still need to be considered in order to develop strong predictive relationships, largely outperforming the use of only one or two descriptors (as conventionally done in the field). Here, we confirmed that the number of d electrons, charge-transfer energy (covalency), and optimality of eg occupancy play the important roles, but found that structural factors such as M-O-M bond angle and tolerance factor are relevant as well. With these tools, we demonstrate how statistical learning can be used to draw novel physical insights and combined with data mining to rapidly screen OER electrocatalysts across a wide chemical space.« less
Shukla, Charu; Koch, Lauren G.; Britton, Steven L.; Cai, Minying; Hruby, Victor J.; Bednarek, Maria; Novak, Colleen M.
2015-01-01
Physical activity and non-exercise activity thermogenesis (NEAT) are crucial factors accounting for individual differences in body weight, interacting with genetic predisposition. In the brain, a number of neuroendocrine intermediates regulate food intake and energy expenditure (EE); this includes the brain melanocortin (MC) system, consisting of melanocortin peptides as well as their receptors (MCR). MC3R and MC4R have emerged as critical modulators of EE and food intake. To determine how variance in MC signaling may underlie individual differences in physical activity levels, we examined behavioral response to MC receptor agonists and antagonists in rats that show high and low levels of physical activity and NEAT, that is, high- and low-capacity runners (HCR, LCR), developed by artificial selection for differential intrinsic aerobic running capacity. Focusing on the hypothalamus, we identified brain region-specific elevations in expression of MCR 3, 4, and also MC5R, in the highly active, lean HCR relative to the less active and obesity-prone LCR. Further, the differences in activity and associated EE as a result of MCR activation or suppression using specific agonists and antagonists were similarly region-specific and directly corresponded to the differential MCR expression patterns. The agonists and antagonists investigated here did not significantly impact food intake at the doses used, suggesting that the differential pattern of receptor expression may by more meaningful to physical activity than to other aspects of energy balance regulation. Thus, MCR-mediated physical activity may be a key neural mechanism in distinguishing the lean phenotype and a target for enhancing physical activity and NEAT. PMID:26404873
Molecular Determinants of Epidermal Growth Factor Binding: A Molecular Dynamics Study
Sanders, Jeffrey M.; Wampole, Matthew E.; Thakur, Mathew L.; Wickstrom, Eric
2013-01-01
The epidermal growth factor receptor (EGFR) is a member of the receptor tyrosine kinase family that plays a role in multiple cellular processes. Activation of EGFR requires binding of a ligand on the extracellular domain to promote conformational changes leading to dimerization and transphosphorylation of intracellular kinase domains. Seven ligands are known to bind EGFR with affinities ranging from sub-nanomolar to near micromolar dissociation constants. In the case of EGFR, distinct conformational states assumed upon binding a ligand is thought to be a determining factor in activation of a downstream signaling network. Previous biochemical studies suggest the existence of both low affinity and high affinity EGFR ligands. While these studies have identified functional effects of ligand binding, high-resolution structural data are lacking. To gain a better understanding of the molecular basis of EGFR binding affinities, we docked each EGFR ligand to the putative active state extracellular domain dimer and 25.0 ns molecular dynamics simulations were performed. MM-PBSA/GBSA are efficient computational approaches to approximate free energies of protein-protein interactions and decompose the free energy at the amino acid level. We applied these methods to the last 6.0 ns of each ligand-receptor simulation. MM-PBSA calculations were able to successfully rank all seven of the EGFR ligands based on the two affinity classes: EGF>HB-EGF>TGF-α>BTC>EPR>EPG>AR. Results from energy decomposition identified several interactions that are common among binding ligands. These findings reveal that while several residues are conserved among the EGFR ligand family, no single set of residues determines the affinity class. Instead we found heterogeneous sets of interactions that were driven primarily by electrostatic and Van der Waals forces. These results not only illustrate the complexity of EGFR dynamics but also pave the way for structure-based design of therapeutics targeting EGF ligands or the receptor itself. PMID:23382875
NASA Astrophysics Data System (ADS)
McKenzie, Iain; Cortie, David L.; Harada, Masashi; Kiefl, Robert F.; Levy, C. D. Philip; MacFarlane, W. Andrew; McFadden, Ryan M. L.; Morris, Gerald D.; Ogata, Shin-Ichi; Pearson, Matthew R.; Sugiyama, Jun
2017-06-01
β -detected NMR (β -NMR) has been used to study the molecular-scale dynamics of lithium ions in thin films of poly(ethylene oxide) (PEO) containing either lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) or lithium trifluoroacetate (LiTFA) salts at monomer-to-salt ratios (EO/Li) of 8.3. The results are compared with previous β -NMR measurements on pure PEO and PEO with lithium triflate (LiOTf) at the same loading [McKenzie et al., J. Am. Chem. Soc. 136, 7833 (2014)]. Activated hopping of 8Li+ was observed in all of the films above ˜250 K, with the hopping parameters strongly correlated with the ionicity of the lithium salt rather than the polymer glass transition temperature. The pre-exponential factor increases exponentially with ionicity, while the activation energy for hopping increases approximately linearly, going from 6.3 ±0.2 kJ mol-1 in PEO:LiTFA to 17.8 ±0.2 kJ mol-1 in PEO:LiTFSI. The more rapid increase in the pre-exponential factor outweighs the effect of the larger activation energy and results in 8Li+ hopping being fastest in PEO followed by PEO:LiTFSI, PEO:LiOTf, and PEO:LiTFA.
McKenzie, Iain; Cortie, David L; Harada, Masashi; Kiefl, Robert F; Levy, C D Philip; MacFarlane, W Andrew; McFadden, Ryan M L; Morris, Gerald D; Ogata, Shin-Ichi; Pearson, Matthew R; Sugiyama, Jun
2017-06-28
β-detected NMR (β-NMR) has been used to study the molecular-scale dynamics of lithium ions in thin films of poly(ethylene oxide) (PEO) containing either lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) or lithium trifluoroacetate (LiTFA) salts at monomer-to-salt ratios (EO/Li) of 8.3. The results are compared with previous β-NMR measurements on pure PEO and PEO with lithium triflate (LiOTf) at the same loading [McKenzie et al., J. Am. Chem. Soc. 136, 7833 (2014)]. Activated hopping of 8 Li + was observed in all of the films above ∼250 K, with the hopping parameters strongly correlated with the ionicity of the lithium salt rather than the polymer glass transition temperature. The pre-exponential factor increases exponentially with ionicity, while the activation energy for hopping increases approximately linearly, going from 6.3±0.2 kJ mol -1 in PEO:LiTFA to 17.8±0.2 kJ mol -1 in PEO:LiTFSI. The more rapid increase in the pre-exponential factor outweighs the effect of the larger activation energy and results in 8 Li + hopping being fastest in PEO followed by PEO:LiTFSI, PEO:LiOTf, and PEO:LiTFA.
Association between Farming and Chronic Energy Deficiency in Rural South India
Subasinghe, Asvini K.; Walker, Karen Z.; Evans, Roger G.; Srikanth, Velandai; Arabshahi, Simin; Kartik, Kamakshi; Kalyanram, Kartik; Thrift, Amanda G.
2014-01-01
Objective To examine factors associated with chronic energy deficiency (CED) and anaemia in disadvantaged Indian adults who are mostly involved in subsistence farming. Design A cross-sectional study in which we collected information on socio-demographic factors, physical activity, anthropometry, blood haemoglobin concentration, and daily household food intake. These data were used to calculate body mass index (BMI), basal metabolic rate (BMR), daily energy expenditure, and energy and nutrient intake. Multivariable backward stepwise logistic regression was used to assess socioeconomic and lifestyle factors associated with CED (defined as BMI<18 kg/m2) and anaemia. Setting The study was conducted in 12 villages, in the Rishi Valley, Andhra Pradesh, India. Subjects Individuals aged 18 years and above, residing in the 12 villages, were eligible to participate. Results Data were available for 1178 individuals (45% male, median age 36 years (inter quartile range (IQR 27–50)). The prevalence of CED (38%) and anaemia (25%) was high. Farming was associated with CED in women (2.20, 95% CI: 1.39–3.49) and men (1.71, 95% CI: (1.06–2.74). Low income was also significantly associated with CED, while not completing high school was positively associated with anaemia. Median iron intake was high: 35.7 mg/day (IQR 26–46) in women and 43.4 mg/day (IQR 34–55) in men. Conclusions Farming is an important risk factor associated with CED in this rural Indian population and low dietary iron is not the main cause of anaemia. Better farming practice may help to reduce CED in this population. PMID:24475286
Nunn, Alistair VW; Bell, Jimmy; Barter, Philip
2007-01-01
The peroxisomal proliferating-activated receptors (PPARs) are lipid-sensing transcription factors that have a role in embryonic development, but are primarily known for modulating energy metabolism, lipid storage, and transport, as well as inflammation and wound healing. Currently, there is no consensus as to the overall combined function of PPARs and why they evolved. We hypothesize that the PPARs had to evolve to integrate lipid storage and burning with the ability to reduce oxidative stress, as energy storage is essential for survival and resistance to injury/infection, but the latter increases oxidative stress and may reduce median survival (functional longevity). In a sense, PPARs may be an evolutionary solution to something we call the 'hypoxia-lipid' conundrum, where the ability to store and burn fat is essential for survival, but is a 'double-edged sword', as fats are potentially highly toxic. Ways in which PPARs may reduce oxidative stress involve modulation of mitochondrial uncoupling protein (UCP) expression (thus reducing reactive oxygen species, ROS), optimising forkhead box class O factor (FOXO) activity (by improving whole body insulin sensitivity) and suppressing NFkB (at the transcriptional level). In light of this, we therefore postulate that inflammation-induced PPAR downregulation engenders many of the signs and symptoms of the metabolic syndrome, which shares many features with the acute phase response (APR) and is the opposite of the phenotype associated with calorie restriction and high FOXO activity. In genetically susceptible individuals (displaying the naturally mildly insulin resistant 'thrifty genotype'), suboptimal PPAR activity may follow an exaggerated but natural adipose tissue-related inflammatory signal induced by excessive calories and reduced physical activity, which normally couples energy storage with the ability to mount an immune response. This is further worsened when pancreatic decompensation occurs, resulting in gluco-oxidative stress and lipotoxicity, increased inflammatory insulin resistance and oxidative stress. Reactivating PPARs may restore a metabolic balance and help to adapt the phenotype to a modern lifestyle. PMID:17531095
Walker, Ian; Verplanken, Bas; Shaddick, Gavin
2016-01-01
If in-home displays and other interventions are to successfully influence people’s energy consumption, they need to communicate about energy in terms that make sense to users. Here we explore householders’ perceptions of energy consumption, using a novel combination of card-sorting and clustering to reveal shared patterns in the way people think about domestic energy consumption. The data suggest that, when participants were asked to group appliances which they felt naturally ‘went together’, there are relatively few shared ideas about which appliances are conceptually related. To the extent participants agreed on which appliances belonged together, these groupings were based on activities (e.g., entertainment) and location within the home (e.g., kitchen); energy consumption was not an important factor in people’s categorisations. This suggests messages about behaviour change aimed at reducing energy consumption might better be tied to social practices than to consumption itself. PMID:27467206
Cascaded H-bridge multilevel inverter for renewable energy generation
NASA Astrophysics Data System (ADS)
Pandey, Ravikant; Nath Tripathi, Ravi; Hanamoto, Tsuyoshi
2016-04-01
In this paper cascaded H-bridge multilevel inverter (CHBMLI) has been investigated for the application of renewable energy generation. Energy sources like solar, wind, hydro, biomass or combination of these can be manipulated to obtain alternative sources for renewable energy generation. These renewable energy sources have different electrical characteristics like DC or AC level so it is challenging to use generated power by connecting to grid or load directly. The renewable energy source require specific power electronics converter as an interface for conditioning generated power .The multilevel inverter can be utilized for renewable energy sources in two different modes, the power generation mode (stand-alone mode), and compensator mode (statcom). The performance of the multilevel inverter has been compared with two level inverter. In power generation mode CHBMLI supplies the active and reactive power required by the different loads. For operation in compensator mode the indirect current control based on synchronous reference frame theory (SRFT) ensures the grid operating in unity power factor and compensate harmonics and reactive power.
Obesity Prevention for Individuals with Spina Bifida.
Polfuss, Michele; Bandini, Linda G; Sawin, Kathleen J
2017-06-01
Obesity is a common comorbidity in individuals with spina bifida. Carrying excess weight exacerbates the inherent health challenges associated with spina bifida, impedes the individual's ability to self-manage their condition, and creates further challenges for family members and caregivers. This manuscript provides a narrative review of key issues for understanding and prevention of obesity in persons with spina bifida within the context of the social ecological model. Specific variables related to obesity and spina bifida include individual factors (i.e., body composition and measurement issues, energy needs, eating patterns, physical activity, and sedentary activity) family factors (i.e., parenting/family, peers), community factors (i.e., culture, built environment, healthcare and healthcare providers, and school), and societal factors (i.e., policy issues). Due to the complex etiology of obesity and its increased prevalence in individuals with spina bifida, it is critical to initiate prevention efforts early with a multifactorial approach for this at-risk population. Increased research is warranted to support these efforts.
Kepler Flares. IV. A Comprehensive Analysis of the Activity of the dM4e Star GJ 1243
NASA Astrophysics Data System (ADS)
Silverberg, Steven M.; Kowalski, Adam F.; Davenport, James R. A.; Wisniewski, John P.; Hawley, Suzanne L.; Hilton, Eric J.
2016-10-01
We present a comprehensive study of the active dM4e star GJ 1243. We use previous observations and ground-based echelle spectroscopy to determine that GJ 1243 is a member of the Argus association of field stars, suggesting it is ∼ 30{--}50 {{Myr}} old. We analyze 11 months of 1 minute cadence data from Kepler, presenting Kepler flare frequency distributions, as well as determining correlations between flare energy, amplitude, duration, and decay time. We find that the exponent α of the power-law flare energy distribution varies in time, primarily due to completeness of sample and the low frequency of high-energy flares. We also find a deviation from a single power law at high energy. We use ground-based spectroscopic observations that were simultaneous with the Kepler data to provide simultaneous photometric and spectroscopic analysis of three low-energy flares, the lowest-energy dMe flares with detailed spectral analysis to date on any star. The spectroscopic data from these flares extend constraints for radiative hydrodynamic flare models to a lower energy regime than has previously been studied. We use this simultaneous spectroscopy and Kepler photometry to develop approximate conversions from the Kepler bandpass to the traditional U and B bands. This conversion will be a critical factor in comparing any Kepler flare analyses to the canon of previous ground-based flare studies.
Research on ion implantation in MEMS device fabrication by theory, simulation and experiments
NASA Astrophysics Data System (ADS)
Bai, Minyu; Zhao, Yulong; Jiao, Binbin; Zhu, Lingjian; Zhang, Guodong; Wang, Lei
2018-06-01
Ion implantation is widely utilized in microelectromechanical systems (MEMS), applied for embedded lead, resistors, conductivity modifications and so forth. In order to achieve an expected device, the principle of ion implantation must be carefully examined. The elementary theory of ion implantation including implantation mechanism, projectile range and implantation-caused damage in the target were studied, which can be regarded as the guidance of ion implantation in MEMS device design and fabrication. Critical factors including implantations dose, energy and annealing conditions are examined by simulations and experiments. The implantation dose mainly determines the dopant concentration in the target substrate. The implantation energy is the key factor of the depth of the dopant elements. The annealing time mainly affects the repair degree of lattice damage and thus the activated elements’ ratio. These factors all together contribute to ions’ behavior in the substrates and characters of the devices. The results can be referred to in the MEMS design, especially piezoresistive devices.
Radiation protection for manned space activities
NASA Technical Reports Server (NTRS)
Jordan, T. M.
1983-01-01
The Earth's natural radiation environment poses a hazard to manned space activities directly through biological effects and indirectly through effects on materials and electronics. The following standard practices are indicated that address: (1) environment models for all radiation species including uncertainties and temporal variations; (2) upper bound and nominal quality factors for biological radiation effects that include dose, dose rate, critical organ, and linear energy transfer variations; (3) particle transport and shielding methodology including system and man modeling and uncertainty analysis; (4) mission planning that includes active dosimetry, minimizes exposure during extravehicular activities, subjects every mission to a radiation review, and specifies operational procedures for forecasting, recognizing, and dealing with large solar flaes.
NASA Astrophysics Data System (ADS)
Bodzin, Alec M.; Fu, Qiong; Kulo, Violet; Peffer, Tamara
2014-08-01
A potential method for teaching geospatial thinking and reasoning (GTR) is through geospatially enabled learning technologies. We developed an energy resources geospatial curriculum that included learning activities with geographic information systems and virtual globes. This study investigated how 13 urban middle school teachers implemented and varied the enactment of the curriculum with their students and investigated which teacher- and student-level factors accounted for students' GTR posttest achievement. Data included biweekly implementation surveys from teachers and energy resources content and GTR pre- and posttest achievement measures from 1,049 students. Students significantly increased both their energy resources content knowledge and their GTR skills related to energy resources at the end of the curriculum enactment. Both multiple regression and hierarchical linear modeling found that students' initial GTR abilities and gain in energy content knowledge were significantly explanatory variables for their geospatial achievement at the end of curriculum enactment, p < .001. Teacher enactment factors, including adherence to implementing the critical components of the curriculum or the number of years the teachers had taught the curriculum, did not have significant effects on students' geospatial posttest achievement. The findings from this study provide support that learning with geospatially enabled learning technologies can support GTR with urban middle-level learners.
NASA Astrophysics Data System (ADS)
Boynton, R. J.; Mourenas, D.; Balikhin, M. A.
2017-11-01
Dropouts in electron fluxes at L ˜ 4.2 were investigated for a broad range of energies from 120 keV to 10 MeV, using 16 years of electron flux data from Combined X-ray Dosimeter on board Global Positioning System (GPS) satellites. Dropouts were defined as flux decreases by at least a factor 4 in 12 h, or 24 h during which a decrease by at least a factor of 1.5 must occur during each 12 h time bin. Such fast and strong dropouts were automatically identified from the GPS electron flux data and statistics of dropout magnitudes, and occurrences were compiled as a function of electron energy. Moreover, the Error Reduction Ratio analysis was employed to search for nonlinear relationships between electron flux dropouts and various solar wind and geomagnetic activity indices, in order to identify potential external causes of dropouts. At L ˜ 4.2, the main driving factor for the more numerous and stronger 1-10 MeV electron dropouts turns out to be the southward interplanetary magnetic field Bs, suggesting an important effect from precipitation loss due to combined electromagnetic ion cyclotron and whistler mode waves in a significant fraction of these events, supplementing magnetopause shadowing and outward radial diffusion which are also effective at lower energies.
Vaasma, Taavi; Kiisk, Madis; Meriste, Tõnis; Tkaczyk, Alan Henry
2014-03-01
Burning oil shale to produce electricity has a dominant position in Estonia's energy sector. Around 90% of the overall electric energy production originates from the Narva Power Plants. The technology in use has been significantly renovated - two older types of pulverized fuel burning (PF) energy production units were replaced with new circulating fluidized bed (CFB) technology. Additional filter systems have been added to PF boilers to reduce emissions. Oil shale contains various amounts of natural radionuclides. These radionuclides concentrate and become enriched in different boiler ash fractions. More volatile isotopes will be partially emitted to the atmosphere via flue gases and fly ash. To our knowledge, there has been no previous study for CFB boiler systems on natural radionuclide enrichment and their atmospheric emissions. Ash samples were collected from Eesti Power Plant's CFB boiler. These samples were processed and analyzed with gamma spectrometry. Activity concentrations (Bq/kg) and enrichment factors were calculated for the (238)U ((238)U, (226)Ra, (210)Pb) and (232)Th ((232)Th, (228)Ra) family radionuclides and for (40)K in different CFB boiler ash fractions. Results from the CFB boiler ash sample analysis showed an increase in the activity concentrations and enrichment factors (up to 4.5) from the furnace toward the electrostatic precipitator block. The volatile radionuclide ((210)Pb and (40)K) activity concentrations in CFB boilers were evenly distributed in finer ash fractions. Activity balance calculations showed discrepancies between input (via oil shale) and output (via ash fractions) activities for some radionuclides ((238)U, (226)Ra, (210)Pb). This refers to a situation where the missing part of the activity (around 20% for these radionuclides) is emitted to the atmosphere. Also different behavior patterns were detected for the two Ra isotopes, (226)Ra and (228)Ra. A part of (226)Ra input activity, unlike (228)Ra, was undetectable in the solid ash fractions of the boiler. Most probably it is released to the surrounding environment. Copyright © 2014 Elsevier Ltd. All rights reserved.
Arruda, Ana Paula; Da-Silva, Wagner S; Carvalho, Denise P; De Meis, Leopoldo
2003-11-01
The sarcoplasmic reticulum Ca2+-ATPase is able to modulate the distribution of energy released during ATP hydrolysis, so that a portion of energy is used for Ca2+ transport (coupled ATPase activity) and a portion is converted into heat (uncoupled ATPase activity). In this report it is shown that T4 administration to rabbits promotes an increase in the rates of both the uncoupled ATPase activity and heat production in sarcoplasmic reticulum vesicles, and that the degree of activation varies depending on the muscle type used. In white muscles hyperthyroidism promotes a 0.8-fold increase of the uncoupled ATPase activity and in red muscle a 4-fold increase. The yield of vesicles from hyperthyroid muscles is 3-4-fold larger than that obtained from normal muscles; thus the rate of heat production by the Ca2+-ATPase expressed in terms of g of muscle in hyperthyroidism is increased by a factor of 3.6 in white muscles and 12.0 in red muscles. The data presented suggest that the Ca2+-ATPase uncoupled activity may represent one of the heat sources that contributes to the enhanced thermogenesis noted in hyperthyroidism.
Kinetics of tumor necrosis factor production by photodynamic-therapy-activated macrophages
NASA Astrophysics Data System (ADS)
Pass, Harvey I.; Evans, Steven; Perry, Roger; Matthews, Wilbert
1990-07-01
The ability of photodynamic therapy (PDT) to activate macrophages and produce cytokines, specifically tumor necrosis factor (TNF), is unknown. Three day thioglycolate elicited macrophages were incubated with 25 ug/mi Photofrin II (P11) for 2 hour, after which they were subjected to 630 nm light with fluences of 0-1800 J/m. The amount of TNF produced in the system as well as macrophage viability was measured 1, 3, 6, and 18 hours after POT. The level of TNF produced by the macrophages was significantly elevated over control levels 6 hours after POT and the absolute level of tumor necrosis factor production was influenced by the treatment energy and the resulting macrophage cytotoxicity. These data suggest that POT therapy induced cytotoxicity in vivo may be amplified by macrophage stimulation to secrete cytokines and these cytokines may also participate in other direct/indirect photodynamic therapy effects, i.e. immunosuppression, vascular effects.
Aeronautics and Space Report of the President: Fiscal Year 1996 Activities
NASA Technical Reports Server (NTRS)
1996-01-01
Topics considered include: (1) Space launch activities: space shuttle missions; expendable launch vehicles. (2) Space science: astronomy and space physics; solar system exploration. (3) Space flight and technology: life and microgravity sciences; space shuttle technology; reuseable launch vehicles; international space station; energy; safety and mission assurance; commercial development and regulation of space; surveillance. (4) Space communications: communications satellites; space network; ground networks; mission control and data systems. (5) Aeronautical activities: technology developments; air traffic control and navigation; weather-related aeronautical activities; flight safety and security; aviation medicine and human factors. (6) Studies of the planet earth: terrestrial studies and applications: atmospheric studies: oceanographic studies; international aeronautical and space activities; and appendices.
Detection of thermogenesis in rodents in response to anti-obesity drugs and genetic modification
Arch, Jonathan R. S.; Trayhurn, Paul
2013-01-01
Many compounds and genetic manipulations are claimed to confer resistance to obesity in rodents by raising energy expenditure. Examples taken from recent and older literature, demonstrate that such claims are often based on measurements of energy expenditure after body composition has changed, and depend on comparisons of energy expenditure divided by body weight. This is misleading because white adipose tissue has less influence than lean tissue on energy expenditure. Application of this approach to human data would suggest that human obesity is usually due to a low metabolic rate, which is not an accepted view. Increased energy expenditure per animal is a surer way of demonstrating thermogenesis, but even then it is important to know whether this is due to altered body composition (repartitioning), or increased locomotor activity rather than thermogenesis per se. Regression analysis offers other approaches. The thermogenic response to some compounds has a rapid onset and so cannot be due to altered body composition. These compounds usually mimic or activate the sympathetic nervous system. Thermogenesis occurs in, but may not be confined to, brown adipose tissue. It should not be assumed that weight loss in response to these treatments is due to thermogenesis unless there is a sustained increase in 24-h energy expenditure. Thyroid hormones and fibroblast growth factor 21 also raise energy expenditure before they affect body composition. Some treatments and genetic modifications alter the diurnal rhythm of energy expenditure. It is important to establish whether this is due to altered locomotor activity or efficiency of locomotion. There are no good examples of compounds that do not affect short-term energy expenditure but have a delayed effect. How and under what conditions a genetic modification or compound increases energy expenditure influences the decision on whether to seek drugs for the target or take a candidate drug into clinical studies. PMID:23580228
A thesis investigating the impact of energy related environmental factors on domestic window design
NASA Astrophysics Data System (ADS)
McEvoy, Michael Edward
In recent years the extent of glazing in houses has been tightly controlled by the Building Regulations in order to save energy. In addition guidelines derived from passive solar principles prescribe the distribution of domestic windows between elevations according to their orientation. This thesis studies the impact of these energy-related environmental factors on domestic window design. The first of these investigations determined the degree to which limitations on the area and arrangement of windows are significant in terms of daylighting. The experiments measured the effect that passive solar requirements and detailed aspects of window design have on the quality of daylighting in houses. The volume of background ventilation required for domestic accommodation has recently been increased. As a result, in a well-sealed construction, heat loss due to background ventilation becomes a larger part of the total heat loss and larger air movements become a potential cause of draughts. The ventilation experiment sought to establish the impact of these more onerous requirements on comfort within rooms. The third experiment combines these factors and asks the question: Could windows be actively involved in overcoming some of these difficulties by being used to preheat ventilation air in order to diminish the extent of heat loss and to alleviate the problem of cold draughts? Also by designing the window to reclaim heat from the room might it be possible to offset the window's thermal inadequacy? Through analysis of responses to a questionnaire and the use of optimisation techniques, scenarios were suggested for the future modification of windows in relation to energy and health expectations. The conclusions form a commentary on recent and future revisions to the Building Regulations and determine whether or not the Regulations facilitate the environmental engineering of windows as an active component of a building's whole environmental system.
SSL Pricing and Efficacy Trend Analysis for Utility Program Planning
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tuenge, Jason R.
2013-10-01
An LED lamp or luminaire can generally be found that matches or exceeds the efficacy of benchmark technologies in a given product category, and LED products continue to expand into ever-higher lumen output niches. However, the price premium for LED continues to pose a barrier to adoption in many applications, in spite of expected savings from reduced energy use and maintenance. Other factors—such as dimmability and quality of light—can also present challenges. The appropriate type, timing, and magnitude of energy efficiency activities will vary from organization to organization based on local variables and the method of evaluation. A number ofmore » factors merit consideration when prioritizing activities for development. Category-specific projections for pricing and efficacy are provided herein to assist in efficiency program planning efforts.« less
The AMP-activated protein kinase beta 1 subunit modulates erythrocyte integrity.
Cambridge, Emma L; McIntyre, Zoe; Clare, Simon; Arends, Mark J; Goulding, David; Isherwood, Christopher; Caetano, Susana S; Reviriego, Carmen Ballesteros; Swiatkowska, Agnieszka; Kane, Leanne; Harcourt, Katherine; Adams, David J; White, Jacqueline K; Speak, Anneliese O
2017-01-01
Failure to maintain a normal in vivo erythrocyte half-life results in the development of hemolytic anemia. Half-life is affected by numerous factors, including energy balance, electrolyte gradients, reactive oxygen species, and membrane plasticity. The heterotrimeric AMP-activated protein kinase (AMPK) is an evolutionarily conserved serine/threonine kinase that acts as a critical regulator of cellular energy balance. Previous roles for the alpha 1 and gamma 1 subunits in the control of erythrocyte survival have been reported. In the work described here, we studied the role of the beta 1 subunit in erythrocytes and observed microcytic anemia with compensatory extramedullary hematopoiesis together with splenomegaly and increased osmotic resistance. Copyright © 2016 ISEH - International Society for Experimental Hematology. Published by Elsevier Inc. All rights reserved.
Kinetic Analysis of the Main Temperature Stage of Fast Pyrolysis
NASA Astrophysics Data System (ADS)
Yang, Xiaoxiao; Zhao, Yuying; Xu, Lanshu; Li, Rui
2017-10-01
Kinetics of the thermal decomposition of eucalyptus chips was evaluated using a high-rate thermogravimetric analyzer (BL-TGA) designed by our research group. The experiments were carried out under non-isothermal condition in order to determine the fast pyrolysis behavior of the main temperature stage (350-540ºC) at heating rates of 60, 120, 180, and 360ºC min-1. The Coats-Redfern integral method and four different reaction mechanism models were adopted to calculate the kinetic parameters including apparent activation energy and pre-exponential factor, and the Flynn-Wall-Ozawa method was employed to testify apparent activation energy. The results showed that estimation value was consistent with the values obtained by linear fitting equations, and the best-fit model for fast pyrolysis was found.
Possible Mechanism of Infrared Radiation Reception: The Role of the Temperature Factor
NASA Astrophysics Data System (ADS)
Yachnev, I. L.; Penniyaynen, V. A.; Podzorova, S. A.; Rogachevskii, I. V.; Krylov, B. V.
2018-02-01
The role of the temperature factor in the mechanism of reception of the CO2 laser low-power infrared (IR) radiation (λ = 10.6 μm) by a sensory neuron membrane has been studied. Organotypic embryonic tissue culture has been used to measure and estimate the temperature of a sensory ganglia monolayer exposed to radiation at different energy densities. The effects of tissue exposure to low-power IR radiation have been investigated. It has been found that inhibition of tissue growth by radiation of low energy density (10-14-10-10 J/cm2) is replaced by tissue growth (10-7-10-4 J/cm2), and again followed by inhibition in the range of 0.1-6 J/cm2. A statistically significant specific reaction to nonthermal radiation has been detected at the radiation power density of 3 × 10-10 J/cm2, which is due to activation of the Na+,K+-ATPase transducer function. The mechanisms of interaction of IR radiation with embryonic nerve tissue have been considered. Low-power IR radiation with the wavelength of 10.6 μm has been demonstrated to specifically activate a novel signal transducer function of the sodium pump, which controls the reception of nonthermal IR radiation in the energy density range of 10-14 to 10-10 J/cm2.
A HUMAN FACTORS META MODEL FOR U.S. NUCLEAR POWER PLANT CONTROL ROOM MODERNIZATION
DOE Office of Scientific and Technical Information (OSTI.GOV)
Joe, Jeffrey C.
Over the last several years, the United States (U.S.) Department of Energy (DOE) has sponsored human factors research and development (R&D) and human factors engineering (HFE) activities through its Light Water Reactor Sustainability (LWRS) program to modernize the main control rooms (MCR) of commercial nuclear power plants (NPP). Idaho National Laboratory (INL), in partnership with numerous commercial nuclear utilities, has conducted some of this R&D to enable the life extension of NPPs (i.e., provide the technical basis for the long-term reliability, productivity, safety, and security of U.S. NPPs). From these activities performed to date, a human factors meta model formore » U.S. NPP control room modernization can now be formulated. This paper discusses this emergent HFE meta model for NPP control room modernization, with the goal of providing an integrated high level roadmap and guidance on how to perform human factors R&D and HFE for those in the U.S. nuclear industry that are engaging in the process of upgrading their MCRs.« less
NASA Astrophysics Data System (ADS)
Korenev, Vladimir V.; Savelyev, Artem V.; Zhukov, Alexey E.; Maximov, Mikhail V.; Omelchenko, Alexander V.
2015-05-01
Ways to improve beam divergence and energy consumption of quantum dot lasers emitting via the ground-state optical transitions by optimization of the key parameters of laser active region are discussed. It is shown that there exist an optimal cavity length, dispersion of inhomogeneous broadening and number of QD layers in active region allowing to obtain lasing spectrum of a given width at minimum injection current. The planar dielectric waveguide of the laser is optimized by analytical means for a better trade-off between high Γ-factor and low beam divergence.
Effects on the orbital debris environment due to solar activity
NASA Technical Reports Server (NTRS)
Kessler, Donald J.; Anz-Meador, Phillip D.
1990-01-01
The rate that earth-orbiting debris is removed from the environment is dependent on a number of factors which include orbital altitude and solar activity. It is generally believed that at lower altitudes and especially during periods of high solar activity, debris generated in the past will be eliminated from the environment. While some debris is eliminated, most is replaced by old debris from higher altitudes or new debris from recent launches. Some low altitude debris, which would reenter if the debris were in circular orbits, does not reenter because the debris is in higher-energy elliptical orbits.
NASA Astrophysics Data System (ADS)
Derishev, E.; Aharonian, F.
We show that, in the presence of radiation field, relativistic bulk flows can very quikly accelerate protons and electrons up to the energies limited either by Hillas criterion or by synchrotron losses. Unlike the traditional approach, we take advantage of continuous photon-induced conversion of charged particle species to neutral ones, and vice versa (proton-neutron or electron-photon). Such a conversion, though it leads to considerable energy losses, allows accelerated particles to increase their energies in each scattering by a factor roughly equal to the bulk Lorentz factor, thus avoiding the need in slow and relatively inefficient diffusive acceleration. The optical depth of accelerating region with respect to inelastic photon-induced reactions (pair production for electrons and photomeson reactions for protons) should be a substancial fraction of unity. Remarkably, self-tuning of the optical depth is automatically achieved as long as the photon density depends on the distance along the bulk flow. This mechanism can work in Gamma-Ray Bursts (GRBs), Active Galactic Nuclei (AGNs), microquasars, or any other object with relativistic bulk flows embedded in radiation-reach environment. Both GRBs and AGNs turn out to be capable of producing 1020 eV cosmic rays.
[Psychometric properties of a self-efficacy scale for physical activity in Brazilian adults].
Rech, Cassiano Ricardo; Sarabia, Tais Taiana; Fermino, Rogério César; Hallal, Pedro Curi; Reis, Rodrigo Siqueira
2011-04-01
To test the validity and reliability of a self-efficacy scale for physical activity (PA) in Brazilian adults. A self-efficacy scale was applied jointly with a multidimensional questionnaire through face-to-face interviews with 1,418 individuals (63.4% women) aged ≥ 18 years. The scale was submitted to validity (factorial and construct) and reliability analysis (internal consistency and temporal stability). A test-retest procedure was conducted with 74 individuals to evaluate temporal stability. Exploratory factor analyses revealed two independent factors: self-efficacy for walking and self-efficacy for moderate and vigorous PA (MVPA). Together, these two factors explained 65.4% of the total variance of the scale (20.9% and 44.5% for walking and MVPA, respectively). Cronbach's alpha values were 0.83 for walking and 0.90 for MVPA, indicating high internal consistency. Both factors were significantly and positively correlated (rho ≥ 0.17, P < 0.001) with quality of life indicators (health perception, self-satisfaction, and energy for daily activities), indicating an adequate construct validity. The scale's validity, internal consistency, and reliability were adequate to evaluate self-efficacy for PA in Brazilian adults.
Pyrolysis and kinetic analyses of Camel grass (Cymbopogon schoenanthus) for bioenergy.
Mehmood, Muhammad Aamer; Ye, Guangbin; Luo, Huibo; Liu, Chenguang; Malik, Sana; Afzal, Ifrah; Xu, Jianren; Ahmad, Muhammad Sajjad
2017-03-01
The aim of this work was to study the thermal degradation of grass (Cymbopogon schoenanthus) under an inert environment at three heating rates, including 10, 30, and 50°Cmin -1 in order to evaluate its bioenergy potential. Pyrolysis experiments were performed in a simultaneous Thermogravimetry-Differential Scanning Calorimetry analyzer. Thermal data were used to analyze kinetic parameters through isoconversional models of Flynn-Wall-Ozawa (FWO) and Kissenger-Akahira-Sunose (KSA) methods. The pre-exponential factors values have shown the reaction to follow first order kinetics. Activation energy values were shown to be 84-193 and 96-192kJmol -1 as calculated by KSA and FWO methods, respectively. Differences between activation energy and enthalpy of reaction values (∼5 to 6kJmol -1 ) showed product formation is favorable. The Gibb's free energy (173-177kJmol -1 ) and High Heating Value (15.00MJkg -1 ) have shown the considerable bioenergy potential of this low-cost biomass. Copyright © 2016 Elsevier Ltd. All rights reserved.
High-energy, high-fat lifestyle challenges an Arctic apex predator, the polar bear.
Pagano, A M; Durner, G M; Rode, K D; Atwood, T C; Atkinson, S N; Peacock, E; Costa, D P; Owen, M A; Williams, T M
2018-02-02
Regional declines in polar bear ( Ursus maritimus ) populations have been attributed to changing sea ice conditions, but with limited information on the causative mechanisms. By simultaneously measuring field metabolic rates, daily activity patterns, body condition, and foraging success of polar bears moving on the spring sea ice, we found that high metabolic rates (1.6 times greater than previously assumed) coupled with low intake of fat-rich marine mammal prey resulted in an energy deficit for more than half of the bears examined. Activity and movement on the sea ice strongly influenced metabolic demands. Consequently, increases in mobility resulting from ongoing and forecasted declines in and fragmentation of sea ice are likely to increase energy demands and may be an important factor explaining observed declines in body condition and survival. Copyright © 2018 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.
Defects in adaptive energy metabolism with CNS-linked hyperactivity in PGC-1alpha null mice.
Lin, Jiandie; Wu, Pei-Hsuan; Tarr, Paul T; Lindenberg, Katrin S; St-Pierre, Julie; Zhang, Chen-Yu; Mootha, Vamsi K; Jäger, Sibylle; Vianna, Claudia R; Reznick, Richard M; Cui, Libin; Manieri, Monia; Donovan, Mi X; Wu, Zhidan; Cooper, Marcus P; Fan, Melina C; Rohas, Lindsay M; Zavacki, Ann Marie; Cinti, Saverio; Shulman, Gerald I; Lowell, Bradford B; Krainc, Dimitri; Spiegelman, Bruce M
2004-10-01
PGC-1alpha is a coactivator of nuclear receptors and other transcription factors that regulates several metabolic processes, including mitochondrial biogenesis and respiration, hepatic gluconeogenesis, and muscle fiber-type switching. We show here that, while hepatocytes lacking PGC-1alpha are defective in the program of hormone-stimulated gluconeogenesis, the mice have constitutively activated gluconeogenic gene expression that is completely insensitive to normal feeding controls. C/EBPbeta is elevated in the livers of these mice and activates the gluconeogenic genes in a PGC-1alpha-independent manner. Despite having reduced mitochondrial function, PGC-1alpha null mice are paradoxically lean and resistant to diet-induced obesity. This is largely due to a profound hyperactivity displayed by the null animals and is associated with lesions in the striatal region of the brain that controls movement. These data illustrate a central role for PGC-1alpha in the control of energy metabolism but also reveal novel systemic compensatory mechanisms and pathogenic effects of impaired energy homeostasis.
Astrocyte glycogen and brain energy metabolism.
Brown, Angus M; Ransom, Bruce R
2007-09-01
The brain contains glycogen but at low concentration compared with liver and muscle. In the adult brain, glycogen is found predominantly in astrocytes. Astrocyte glycogen content is modulated by a number of factors including some neurotransmitters and ambient glucose concentration. Compelling evidence indicates that astrocyte glycogen breaks down during hypoglycemia to lactate that is transferred to adjacent neurons or axons where it is used aerobically as fuel. In the case of CNS white matter, this source of energy can extend axon function for 20 min or longer. Likewise, during periods of intense neural activity when energy demand exceeds glucose supply, astrocyte glycogen is degraded to lactate, a portion of which is transferred to axons for fuel. Astrocyte glycogen, therefore, offers some protection against hypoglycemic neural injury and ensures that neurons and axons can maintain their function during very intense periods of activation. These emerging principles about the roles of astrocyte glycogen contradict the long held belief that this metabolic pool has little or no functional significance.
NASA Astrophysics Data System (ADS)
He, Xunjun; Yao, Yuan; Yang, Xingyu; Lu, Guangjun; Yang, Wenlong; Yang, Yuqiang; Wu, Fengmin; Yu, Zhigang; Jiang, Jiuxing
2018-03-01
By patterning two graphene resonators on a SiO2/Si substrate, a dynamically controlled electromagnetically induced transparency (EIT) in the terahertz graphene metamaterial was numerically studied through tuning the structural parameter and Fermi energy of graphene. The calculated surface current distributions demonstrate that the distinct EIT window in the graphene metamaterial results from the near-field coupling of two graphene resonators. Moreover, the EIT window can be actively controlled by tuning Fermi energy combined states of two resonators. When the Fermi energy combined state of two resonators changes from (0.21 and 0.16 eV) to (0.4 and 0.11 eV), the amplitude modulation depth of the EIT peak is 97.8% at 0.45 THz, and the corresponding enhanced factor of group delay with 6 times is obtained. This study offers an alternative tuning method to existing optical, thermal, and relative distance tuning, delivering a promising potential for designing active and miniaturized THz devices.
NASA Astrophysics Data System (ADS)
So, Woo-Young; Lang, David; Ramirez, Arthur
2008-03-01
We develop a spectroscopic method for determining the density of states (DOS) in the energy gap - GAte Modulated activation Energy Spectroscopy (GAMEaS), We also report the relationship of these gap states to the mobility of organic field-effect-transistors (FETs). We find that the field-effect mobility is parameterized by two factors: (1) the free-carrier mobility and (2) the ratio of the free carrier density to the total carrier density induced by the gate bias. We show that the highest mobility FETs have shallow exponential band tails of localized states with characteristic slope of 1/kT at 300K. Most remarkably, state-of-the-art crystalline FETs fabricated from rubrene, pentacene, and tetracene all have a very high free-carrier mobility, up to 200cm2/Vsec at 300K, with the somewhat lower effective mobilities dominated by localized gap states. This strongly suggests that further improvements in device performance could be possible with enhanced material quality.
Kinetic characterization of the deproteinization of trabecular and cortical bovine femur bones.
Castro-Ceseña, Ana B; Sánchez-Saavedra, M Pilar; Novitskaya, Ekaterina E; Chen, Po-Yu; Hirata, Gustavo A; McKittrick, Joanna
2013-12-01
The present study proposes an interpretation of the mechanism of bone deproteinization. Cortical and trabecular bovine femur bones were deproteinized using 6% NaOCl (37, 50, 60°C). The kinetic parameters (rate constant and activation energy) were calculated, and the surface area of each type of bone was considered. A statistical analysis of the rate constants shows that cortical bone deproteinizes at a lower rate than trabecular. The activation energy is higher for trabecular than cortical bone, and no significant differences are found in the protein concentration values for both bones. Therefore, although trabecular bone deproteinizes at a higher rate than cortical, trabecular bone requires more energy for the deproteinization reaction to take place. Considering that both types of bones are constituted by mineral, protein, and water; the present work shows that the individual inner matrix architecture of trabecular and cortical bones, along with characteristics such as the mineral concentration and its bonding with collagen fibers, may be the responsible factors that control protein depletion. © 2013.
Intrinsic Brightness Temperatures of AGN Jets
NASA Astrophysics Data System (ADS)
Homan, D. C.; Kovalev, Y. Y.; Lister, M. L.; Ros, E.; Kellermann, K. I.; Cohen, M. H.; Vermeulen, R. C.; Zensus, J. A.; Kadler, M.
2006-05-01
We present a new method for studying the intrinsic brightness temperatures of the parsec-scale jet cores of active galactic nuclei (AGNs). Our method uses observed superluminal motions and observed brightness temperatures for a large sample of AGNs to constrain the characteristic intrinsic brightness temperature of the sample as a whole. To study changes in intrinsic brightness temperature, we assume that the Doppler factors of individual jets are constant in time, as justified by their relatively small changes in observed flux density. We find that in their median-low brightness temperature state, the sources in our sample have a narrow range of intrinsic brightness temperatures centered on a characteristic temperature, Tint~=3×1010 K, which is close to the value expected for equipartition, when the energy in the radiating particles equals the energy stored in the magnetic fields. However, in their maximum brightness state, we find that sources in our sample have a characteristic intrinsic brightness temperature greater than 2×1011 K, which is well in excess of the equipartition temperature. In this state, we estimate that the energy in radiating particles exceeds the energy in the magnetic field by a factor of ~105. We suggest that the excess of particle energy when sources are in their maximum brightness state is due to injection or acceleration of particles at the base of the jet. Our results suggest that the common method of estimating jet Doppler factors by using a single measurement of observed brightness temperature, the assumption of equipartition, or both may lead to large scatter or systematic errors in the derived values.
Izewska, Joanna; Georg, Dietmar; Bera, Pranabes; Thwaites, David; Arib, Mehenna; Saravi, Margarita; Sergieva, Katia; Li, Kaibao; Yip, Fernando Garcia; Mahant, Ashok Kumar; Bulski, Wojciech
2007-07-01
A strategy for national TLD audit programmes has been developed by the International Atomic Energy Agency (IAEA). It involves progression through three sequential dosimetry audit steps. The first step audits are for the beam output in reference conditions for high-energy photon beams. The second step audits are for the dose in reference and non-reference conditions on the beam axis for photon and electron beams. The third step audits involve measurements of the dose in reference, and non-reference conditions off-axis for open and wedged symmetric and asymmetric fields for photon beams. Through a co-ordinated research project the IAEA developed the methodology to extend the scope of national TLD auditing activities to more complex audit measurements for regular fields. Based on the IAEA standard TLD holder for high-energy photon beams, a TLD holder was developed with horizontal arm to enable measurements 5cm off the central axis. Basic correction factors were determined for the holder in the energy range between Co-60 and 25MV photon beams. New procedures were developed for the TLD irradiation in hospitals. The off-axis measurement methodology for photon beams was tested in a multi-national pilot study. The statistical distribution of dosimetric parameters (off-axis ratios for open and wedge beam profiles, output factors, wedge transmission factors) checked in 146 measurements was 0.999+/-0.012. The methodology of TLD audits in non-reference conditions with a modified IAEA TLD holder has been shown to be feasible.
Monge, Claire; Beraud, Nathalie; Tepp, Kersti; Pelloux, Sophie; Chahboun, Siham; Kaambre, Tuuli; Kadaja, Lumme; Roosimaa, Mart; Piirsoo, Andres; Tourneur, Yves; Kuznetsov, Andrey V; Saks, Valdur; Seppet, Enn
2009-04-01
Comparative analysis of the bioenergetic parameters of adult rat cardiomyocytes (CM) and HL-1 cells with very different structure but similar cardiac phenotype was carried out with the aim of revealing the importance of the cell structure for regulation of its energy fluxes. Confocal microscopic analysis showed very different mitochondrial arrangement in these cells. The cytochrome content per milligram of cell protein was decreased in HL-1 cells by a factor of 7 compared with CM. In parallel, the respiratory chain complex activities were decreased by 4-8 times in the HL-1 cells. On the contrary, the activities of glycolytic enzymes, hexokinase (HK), and pyruvate kinase (PK) were increased in HL-1 cells, and these cells effectively transformed glucose into lactate. At the same time, the creatine kinase (CK) activity was significantly decreased in HL-1 cells. In conclusion, the results of this study comply with the assumption that in contrast to CM in which oxidative phosphorylation is a predominant provider of ATP and the CK system is a main carrier of energy from mitochondria to ATPases, in HL-1 cells the energy metabolism is based mostly on the glycolytic reactions coupled to oxidative phosphorylation through HK.
Xue, Yang; Chen, Qingqing; Ding, Tingting; Sun, Jiao
2014-01-01
The liver has been shown to be a primary target organ for SiO2 nanoparticles in vivo, and may be highly susceptible to damage by these nanoparticles. However, until now, research focusing on the potential toxic effects of SiO2 nanoparticles on mitochondria-associated energy metabolism in hepatocytes has been lacking. In this work, SiO2 nanoparticles 20 nm in diameter were evaluated for their ability to induce dysfunction of mitochondrial energy metabolism. First, a buffalo rat liver (BRL) cell line was directly exposed to SiO2 nanoparticles, which induced cytotoxicity and mitochondrial damage accompanied by decreases in mitochondrial dehydrogenase activity, mitochondrial membrane potential, enzymatic expression in the Krebs cycle, and activity of the mitochondrial respiratory chain complexes I, III and IV. Second, the role of rat-derived Kupffer cells was evaluated. The supernatants from Kupffer cells treated with SiO2 nanoparticles were transferred to stimulate BRL cells. We observed that SiO2 nanoparticles had the ability to activate Kupffer cells, leading to release of tumor necrosis factor-α, nitric oxide, and reactive oxygen species from these cells and subsequently to inhibition of mitochondrial respiratory chain complex I activity in BRL cells. PMID:24959077
Calderón, Juan Carlos; Rios Ráfales, Miguel; Nieto-Monge, María Jesús; Pardo, Juan Ignacio; Moliner, Rafael; Lázaro, María Jesús
2016-01-01
In this work, palladium-nickel nanoparticles supported on carbon nanofibers were synthesized, with metal contents close to 25 wt % and Pd:Ni atomic ratios near to 1:2. These catalysts were previously studied in order to determine their activity toward the oxygen reduction reaction. Before the deposition of metals, the carbon nanofibers were chemically treated in order to generate oxygen and nitrogen groups on their surface. Transmission electron microscopy analysis (TEM) images revealed particle diameters between 3 and 4 nm, overcoming the sizes observed for the nanoparticles supported on carbon black (catalyst Pd-Ni CB 1:2). From the CO oxidation at different temperatures, the activation energy Eact for this reaction was determined. These values indicated a high tolerance of the catalysts toward the CO poisoning, especially in the case of the catalysts supported on the non-chemically treated carbon nanofibers. On the other hand, apparent activation energy Eap for the methanol oxidation was also determined finding—as a rate determining step—the COads diffusion to the OHads for the catalysts supported on carbon nanofibers. The results here presented showed that the surface functional groups only play a role in the obtaining of lower particle sizes, which is an important factor in the obtaining of low CO oxidation activation energies. PMID:28335315
Goto, Tsuyoshi; Kim, Young-Il; Takahashi, Nobuyuki; Kawada, Teruo
2013-01-01
Obesity causes excess fat accumulation in various tissues, most notoriously in the adipose tissue, along with other insulin-responsive organs such as skeletal muscle and the liver, which predisposes an individual to the development of metabolic abnormalities. The molecular mechanisms underlying obesity-induced metabolic abnormalities have not been completely elucidated; however, in recent years, the search for therapies to prevent the development of obesity and obesity-associated metabolic disorders has increased. It is known that several nuclear receptors, when activated by specific ligands, regulate carbohydrate and lipid metabolism at the transcriptional level. The expression of lipid metabolism-related enzymes is directly regulated by the activity of various nuclear receptors via their interaction with specific response elements in promoters of those genes. Many natural compounds act as ligands of nuclear receptors and regulate carbohydrate and lipid metabolism by regulating the activities of these nuclear receptors. In this review, we describe our current knowledge of obesity, the role of lipid-sensing nuclear receptors in energy metabolism, and several examples of food factors that act as agonists or antagonists of nuclear receptors, which may be useful for the management of obesity and the accompanying energy metabolism abnormalities. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
ERIC Educational Resources Information Center
Salvador, F.; And Others
1984-01-01
Describes a method which adapts itself to the characteristics of the kinetics of a chemical reaction in solution, enabling students to determine the Arrhenius parameters with satisfactory accuracy by means of a single non-isothermic experiment. Both activation energy and the preexponential factor values can be obtained by the method. (JN)
10 CFR 72.94 - Design basis external man-induced events.
Code of Federal Regulations, 2014 CFR
2014-01-01
... 10 Energy 2 2014-01-01 2014-01-01 false Design basis external man-induced events. 72.94 Section 72... WASTE Siting Evaluation Factors § 72.94 Design basis external man-induced events. (a) The region must be examined for both past and present man-made facilities and activities that might endanger the proposed...
10 CFR 72.94 - Design basis external man-induced events.
Code of Federal Regulations, 2011 CFR
2011-01-01
... 10 Energy 2 2011-01-01 2011-01-01 false Design basis external man-induced events. 72.94 Section 72... WASTE Siting Evaluation Factors § 72.94 Design basis external man-induced events. (a) The region must be examined for both past and present man-made facilities and activities that might endanger the proposed...
10 CFR 72.94 - Design basis external man-induced events.
Code of Federal Regulations, 2013 CFR
2013-01-01
... 10 Energy 2 2013-01-01 2013-01-01 false Design basis external man-induced events. 72.94 Section 72... WASTE Siting Evaluation Factors § 72.94 Design basis external man-induced events. (a) The region must be examined for both past and present man-made facilities and activities that might endanger the proposed...
10 CFR 72.94 - Design basis external man-induced events.
Code of Federal Regulations, 2012 CFR
2012-01-01
... 10 Energy 2 2012-01-01 2012-01-01 false Design basis external man-induced events. 72.94 Section 72... WASTE Siting Evaluation Factors § 72.94 Design basis external man-induced events. (a) The region must be examined for both past and present man-made facilities and activities that might endanger the proposed...
USDA-ARS?s Scientific Manuscript database
The prevalence of overweight in African American (AA) girls is higher than other ethnic groups. Increasing physical activity (PA) or decreasing energy intake is the goal of obesity prevention programs. Identifying factors that influence PA behavior is an important step in developing successful obesi...
Arha, Deepti; Ramakrishna, E; Gupta, Anand P; Rai, Amit K; Sharma, Aditya; Ahmad, Ishbal; Riyazuddin, Mohammed; Gayen, Jiaur R; Maurya, Rakesh; Tamrakar, Akhilesh K
2018-01-15
Augmenting glucose utilization and energy expenditure in skeletal muscle via AMP-activated protein kinase (AMPK) is an imperative mechanism for the management of type 2 diabetes. Chemical derivatives (2a-2h, 3, 4a-4d, 5) of the isoalantolactone (K007), a bioactive molecule from roots of Inula racemosa were synthesized to optimize the bioactivity profile to stimulate glucose utilization in skeletal muscle cells. Interestingly, 4a augmented glucose uptake, driven by enhanced translocation of glucose transporter 4 (GLUT4) to cell periphery in L6 rat skeletal muscle cells. The effect of 4a was independent to phosphatidylinositide-3-kinase (PI-3-K)/Akt pathway, but mediated through Liver kinase B1 (LKB1)/AMPK-dependent signaling, leading to activation of downstream targets acetyl coenzyme A carboxylase (ACC) and sterol regulatory element binding protein 1c (SREBP-1c). In db/db mice, 4a administration decreased blood glucose level and improved body mass index, lipid parameters and glucose tolerance associated with elevation of GLUT4 expression in skeletal muscle. Moreover, 4a increased energy expenditure via activating substrate utilization and upregulated the expression of thermogenic transcription factors and mitochondrial proteins in skeletal muscle, suggesting the regulation of energy balance. These findings suggest the potential implication of isoalantolactone derivatives for the management of diabetes. Copyright © 2017 Elsevier B.V. All rights reserved.