Science.gov

Sample records for active heat production

  1. The Chemistry of Self-Heating Food Products: An Activity for Classroom Engagement

    ERIC Educational Resources Information Center

    Oliver-Hoyo, Maria T.; Pinto, Gabriel; Llorens-Molina, Juan Antonio

    2009-01-01

    Two commercial self-heating food products have been used to apply chemical concepts such as stoichiometry, enthalpies of reactions and solutions, and heat transfer in a classroom activity. These products are the self-heating beverages sold in Europe and the Meals, Ready to Eat or MREs used primarily by the military in the United States. The main…

  2. Dynamics of locomotor activity and heat production in rats after acute stress.

    PubMed

    Pertsov, S S; Alekseeva, I V; Koplik, E V; Sharanova, N E; Kirbaeva, N V; Gapparov, M M G

    2014-05-01

    The dynamics of locomotor activity and heat production were studied in rats demonstrating passive and active behavior in the open field test at different time after exposure to acute emotional stress caused by 12-h immobilization during dark hours. The most pronounced changes in behavior and heat production followed by disturbances in circadian rhythms of these parameters were detected within the first 2 days after stress. In contrast to behaviorally active rats, the most significant decrease in locomotor activity and heat production of passive animals subjected to emotional stress was observed during dark hours. Circadian rhythms of behavior and heat production in rats tended to recover on day 3 after immobilization stress. These data illustrate the specificity of metabolic and behavioral changes reflecting the shift of endogenous biological rhythms in individuals with different prognostic resistance to stress at different terms after exposure to negative emotiogenic stimuli. PMID:24906959

  3. Hyperthyroidism increases the uncoupled ATPase activity and heat production by the sarcoplasmic reticulum Ca2+-ATPase.

    PubMed Central

    Arruda, Ana Paula; Da-Silva, Wagner S; Carvalho, Denise P; De Meis, Leopoldo

    2003-01-01

    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. PMID:12887329

  4. Enhancement of anaerobic biohydrogen/methane production from cellulose using heat-treated activated sludge.

    PubMed

    Lay, C H; Chang, F Y; Chu, C Y; Chen, C C; Chi, Y C; Hsieh, T T; Huang, H H; Lin, C Y

    2011-01-01

    Anaerobic digestion is an effective technology to convert cellulosic wastes to methane and hydrogen. Heat-treatment is a well known method to inhibit hydrogen-consuming bacteria in using anaerobic mixed cultures for seeding. This study aims to investigate the effects of heat-treatment temperature and time on activated sludge for fermentative hydrogen production from alpha-cellulose by response surface methodology. Hydrogen and methane production was evaluated based on the production rate and yield (the ability of converting cellulose into hydrogen and methane) with heat-treated sludge as the seed at various temperatures (60-97 degrees C) and times (20-60 min). Batch experiments were conducted at 55 degrees C and initial pH of 8.0. The results indicate that hydrogen and methane production yields peaked at 4.3 mmol H2/g cellulose and 11.6 mmol CH4/g cellulose using the seed activated sludge that was thermally treated at 60 degrees C for 40 min. These parameter values are higher than those of no-treatment seed (HY 3.6 mmol H2/g cellulose and MY 10.4 mmol CH4/g cellulose). The maximum hydrogen production rate of 26.0 mmol H2/L/d and methane production rate of 23.2 mmol CH4/L/d were obtained for the seed activated sludge that was thermally treated at 70 degrees C for 50 min and 60 degrees C for 40 min, respectively.

  5. Oxidation of chlorinated ethenes by heat-activated persulfate: kinetics and products.

    PubMed

    Waldemer, Rachel H; Tratnyek, Paul G; Johnson, Richard L; Nurmi, James T

    2007-02-01

    In situ chemical oxidation (ISCO) and in situ thermal remediation (ISTR) are applicable to treatment of groundwater contaminated with chlorinated ethenes. ISCO with persulfate (S2O8(2-)) requires activation, and this can be achieved with the heat from ISTR, so there may be advantages to combining these technologies. To explore this possibility, we determined the kinetics and products of chlorinated ethene oxidation with heat-activated persulfate and compared them to the temperature dependence of other degradation pathways. The kinetics of chlorinated ethene disappearance were pseudo-first-order for 1-2 half-lives, and the resulting rate constants-measured from 30 to 70 degrees C--fit the Arrhenius equation, yielding apparent activation energies of 101 +/- 4 kJ mol(-1) for tetrachloroethene (PCE), 108 +/- 3 kJ mol(-1) for trichloroethene (TCE), 144 +/- 5 kJ mol(-1) for cis-1,2-dichloroethene (cis-DCE), and 141 +/- 2 kJ mol(-1) for trans-1,2-dichloroethene (trans-DCE). Chlorinated byproducts were observed, but most of the parent material was completely dechlorinated. Arrhenius parameters for hydrolysis and oxidation by persulfate or permanganate were used to calculate rates of chlorinated ethene degradation by these processes over the range of temperatures relevant to ISTR and the range of oxidant concentrations and pH relevant to ISCO.

  6. Enhancing methane production from waste activated sludge using combined free nitrous acid and heat pre-treatment.

    PubMed

    Wang, Qilin; Jiang, Guangming; Ye, Liu; Yuan, Zhiguo

    2014-10-15

    Methane production from anaerobic digestion of waste activated sludge (WAS) is often limited by the slow degradation and poor substrate availability of WAS. Our previous study revealed that WAS pre-treatment using free nitrous acid (FNA, i.e. HNO2) is an economically feasible and environmentally friendly method for promoting methane production. In order to further improve methane production from WAS, this study presents a novel strategy based on combined FNA and heat pre-treatment. WAS from a full-scale plant was treated for 24 h with FNA alone (0.52-1.43 mg N/L at 25 °C), heat alone (35, 55 and 70 °C), and FNA (0.52-1.11 mg N/L) combined with heat (35, 55 and 70 °C). The pre-treated WAS was then used for biochemical methane potential tests. Compared to the control (no FNA or heat pre-treatment of WAS), biochemical methane potential of the pre-treated WAS was increased by 12-16%, 0-6%, 17-26%, respectively; hydrolysis rate was improved by 15-25%, 10-25%, 20-25%, respectively, for the three types of pre-treatment. Heat pre-treatment at 55 and 70 °C, independent of the presence or absence of FNA, achieved approximately 4.5 log inactivation of pathogens (in comparison to ∼1 log inactivation with FNA treatment alone), thus capable of producing Class A biosolids. The combined FNA and heat pre-treatment is an economically and environmentally attractive technology for the pre-treatment of WAS prior to anaerobic digestion, particularly considering that both FNA and heat can be produced as by-products of anaerobic sludge digestion.

  7. Active microchannel heat exchanger

    DOEpatents

    Tonkovich, Anna Lee Y [Pasco, WA; Roberts, Gary L [West Richland, WA; Call, Charles J [Pasco, WA; Wegeng, Robert S [Richland, WA; Wang, Yong [Richland, WA

    2001-01-01

    The present invention is an active microchannel heat exchanger with an active heat source and with microchannel architecture. The microchannel heat exchanger has (a) an exothermic reaction chamber; (b) an exhaust chamber; and (c) a heat exchanger chamber in thermal contact with the exhaust chamber, wherein (d) heat from the exothermic reaction chamber is convected by an exothermic reaction exhaust through the exhaust chamber and by conduction through a containment wall to the working fluid in the heat exchanger chamber thereby raising a temperature of the working fluid. The invention is particularly useful as a liquid fuel vaporizer and/or a steam generator for fuel cell power systems, and as a heat source for sustaining endothermic chemical reactions and initiating exothermic reactions.

  8. Activation of Heat Shock and Antioxidant Responses by the Natural Product Celastrol: Transcriptional Signatures of a Thiol-targeted Molecule

    PubMed Central

    Trott, Amy; West, James D.; Klaić, Lada; Westerheide, Sandy D.; Silverman, Richard B.; Morimoto, Richard I.

    2008-01-01

    Stress response pathways allow cells to sense and respond to environmental changes and adverse pathophysiological states. Pharmacological modulation of cellular stress pathways has implications in the treatment of human diseases, including neurodegenerative disorders, cardiovascular disease, and cancer. The quinone methide triterpene celastrol, derived from a traditional Chinese medicinal herb, has numerous pharmacological properties, and it is a potent activator of the mammalian heat shock transcription factor HSF1. However, its mode of action and spectrum of cellular targets are poorly understood. We show here that celastrol activates Hsf1 in Saccharomyces cerevisiae at a similar effective concentration seen in mammalian cells. Transcriptional profiling revealed that celastrol treatment induces a battery of oxidant defense genes in addition to heat shock genes. Celastrol activated the yeast Yap1 oxidant defense transcription factor via the carboxy-terminal redox center that responds to electrophilic compounds. Antioxidant response genes were likewise induced in mammalian cells, demonstrating that the activation of two major cell stress pathways by celastrol is conserved. We report that celastrol's biological effects, including inhibition of glucocorticoid receptor activity, can be blocked by the addition of excess free thiol, suggesting a chemical mechanism for biological activity based on modification of key reactive thiols by this natural product. PMID:18199679

  9. Repeat mild heat shock increases dermal fibroblast activity and collagen production.

    PubMed

    Mayes, Andrew E; Holyoak, Caroline D

    2008-04-01

    Repeat mild heat shock (RMHS) has been shown to have anti-aging effects on cellular and biological processes within human dermal fibroblasts. We have investigated the potential of an abridged mild heat shock regime to impact upon the functional properties of human dermal fibroblasts derived from three donors (male, 12 years; female, 22 years; female, 65 years). For each donor mild heat shock increased the rate of contraction of fibroblast-containing collagen gels and increased the de novo synthesis of collagen. Thus, hormetic mechanisms are proposed to provide functional anti-aging benefits to skin cells.

  10. Pulsed nanosecond discharge in air at high specific deposited energy: fast gas heating and active particle production

    NASA Astrophysics Data System (ADS)

    Popov, N. A.

    2016-08-01

    The results of a numerical study on kinetic processes initiated by a pulsed nanosecond discharge in air at high specific deposited energy, when the dissociation degree of oxygen molecules is high, are presented. The calculations of the temporal dynamics of the electron concentration, density of atomic oxygen, vibrational distribution function of nitrogen molecules, and gas temperature agree with the experimental data. It is shown that quenching of electronically excited states of nitrogen N2(B3Πg), N2(C3Πu), N2(a‧1 Σ \\text{u}- ) by oxygen molecules leads to the dissociation of O2. This conclusion is based on the comparison of calculated dynamics of atomic oxygen in air, excited by a pulsed nanosecond discharge, with experimental data. In air plasma at a high dissociation degree of oxygen molecules ([O]/[O2] > 10%), relaxation of the electronic energy of atoms and molecules in reactions with O atoms becomes extremely important. Active production of NO molecules and fast gas heating in the discharge plasma due to the quenching of electronically excited N2(B3Πg, C3Πu, a‧1 Σ \\text{u}- ) molecules by oxygen atoms is notable. Owing to the high O atom density, electrons are effectively detached from negative ions in the discharge afterglow. As a result, the decay of plasma in the afterglow is determined by electron-ion recombination, and the electron density remains relatively high between the pulses. An increase in the vibrational temperature of nitrogen molecules at the periphery of the plasma channel at time delay t = 1-30 μs after the discharge is obtained. This is due to intense gas heating and, as a result, gas-dynamic expansion of a hot gas channel. Vibrationally excited N2(v) molecules produced near the discharge axis move from the axial region to the periphery. Consequently, at the periphery the vibrational temperature of nitrogen molecules is increased.

  11. Effects of atrophic rhinitis induced by Pasteurella multocida toxin on heat production and activity of pigs kept under different climatic conditions.

    PubMed

    van Diemen, P M; Henken, A M; Schrama, J W; Brandsma, H A; Verstegen, M W

    1995-06-01

    Effects of moderate, artificially induced atrophic rhinitis symptoms on level and changes in heat production and activity were determined in pigs kept under different climatic conditions. Eight groups of 30 pigs each, housed in one of two climatically controlled respiration chambers, were exposed to a 2 x 2 factorial arrangement of treatments: challenged with 0 or 13 micrograms of Pasteurella multocida toxin (Pm-T)/mL, and two climatic environments (good: 25 degrees C, or adverse: 15 degrees C with draught periods). The Pm-T challenge reduced (P < .05) day averages of total (HP) and activity-related heat production (Har). The response to Pm-T treatment was similar in both climatic environments. Differences in the heat production and activity caused by the climatic treatment declined (P < .001) with time and acclimation to the environment. Analyses of HP, Har, and activity-free heat production in 12 2-h periods showed a biphasic activity rhythm. Both treatments affected (P < .05) level of HP and Har in several of the 2-h periods, but the biphasic rhythm was not altered. Day averages of Har showed a disposition to be differently affected (P < .068) by Pm-T challenge in the climatic treatments dependent on duration of exposure. This interaction effect (P < .001) seemed to originate from the periods between 1500 and 2100. Therefore, it might be wise to distinguish between overall effects (day means) on total, activity-related, and activity-free heat production and effects within a day (e.g., 2-h means). Treatment with Pm-T seemed to suppress the general well-being of pigs, reducing pigs' activity and food intake.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7673059

  12. Pulsed nanosecond discharge in air at high specific deposited energy: fast gas heating and active particle production

    NASA Astrophysics Data System (ADS)

    Popov, N. A.

    2016-08-01

    The results of a numerical study on kinetic processes initiated by a pulsed nanosecond discharge in air at high specific deposited energy, when the dissociation degree of oxygen molecules is high, are presented. The calculations of the temporal dynamics of the electron concentration, density of atomic oxygen, vibrational distribution function of nitrogen molecules, and gas temperature agree with the experimental data. It is shown that quenching of electronically excited states of nitrogen N2(B3Πg), N2(С3Πu), N2(a‧1 Σ \\text{u}- ) by oxygen molecules leads to the dissociation of O2. This conclusion is based on the comparison of calculated dynamics of atomic oxygen in air, excited by a pulsed nanosecond discharge, with experimental data. In air plasma at a high dissociation degree of oxygen molecules ([O]/[O2]  >  10%), relaxation of the electronic energy of atoms and molecules in reactions with O atoms becomes extremely important. Active production of NO molecules and fast gas heating in the discharge plasma due to the quenching of electronically excited N2(B3Πg, C3Πu, a‧1 Σ \\text{u}- ) molecules by oxygen atoms is notable. Owing to the high O atom density, electrons are effectively detached from negative ions in the discharge afterglow. As a result, the decay of plasma in the afterglow is determined by electron–ion recombination, and the electron density remains relatively high between the pulses. An increase in the vibrational temperature of nitrogen molecules at the periphery of the plasma channel at time delay t  =  1–30 μs after the discharge is obtained. This is due to intense gas heating and, as a result, gas-dynamic expansion of a hot gas channel. Vibrationally excited N2(v) molecules produced near the discharge axis move from the axial region to the periphery. Consequently, at the periphery the vibrational temperature of nitrogen molecules is increased.

  13. Radiogenic heat production in the continental crust

    NASA Astrophysics Data System (ADS)

    Jaupart, Claude; Mareschal, Jean-Claude; Iarotsky, Lidia

    2016-10-01

    , suggesting an intrinsic thermal control on crustal thickness and heat production distribution. Crustal thickening by more than about 10 km above this mean value induces changes of gravitational potential energy that exceed the strength of the lithosphere. For several provinces where strong constraints on heat production are available, it is shown that, prior to intracrustal fractionation, only modest amounts of thickening were needed to generate the conditions of ultra-high temperature metamorphism. The tell-tale signature of crustal heat production is anatectic and metamorphic events that lag the cessation of orogenic activity by several tens of million years. Crustal heat production is decreasing with time because it is due to the radioactive decay of Uranium Thorium and Potassium. Its rundown is responsible for the secular cooling of lithospheric roots at a typical rate of about 100 K Gy - 1, implying complex thermal interactions with a convecting mantle that is not cooling at the same rate.

  14. Heat production in different populations of human blood cells exposed to immune complexes in vitro: the importance of the Fc parts of immunoglobulins and the influence of active complement.

    PubMed Central

    Fäldt, R; Ankerst, J; Monti, M; Wadsö, I

    1982-01-01

    By use of a batch microcalorimeter of the thermopile type, heat production was measured in isolated populations of human peripheral blood cells exposed to defined immune complexes formed in vitro. It was found that most of the heat production recorded in whole blood after admixture of immune complexes occurs in the granulocytes. Under these conditions small but constantly higher activation values were found in the absence of active complement. It was shown that complexes consisting of antigen and F(ab)2 fragments prepared from the specific antibodies were able to initiate heat production in the cells only in the presence of active complement. These experiments indicate that immune complexes are able to induce increased heat production in the cells either by binding to Fc receptors or by activation of complement through the alternative pathway and subsequent binding of the generated C3b to C3b receptors on the heat-producing cells. PMID:7076279

  15. Fusion production of solid dispersions containing a heat-sensitive active ingredient by hot melt extrusion and Kinetisol dispersing.

    PubMed

    Dinunzio, James C; Brough, Chris; Hughey, Justin R; Miller, Dave A; Williams, Robert O; McGinity, James W

    2010-02-01

    Many techniques for the production of solid dispersions rely on elevated temperatures and prolonged material residence times, which can result in decomposition of temperature-sensitive components. In this study, hydrocortisone was used as a model temperature-sensitive active ingredient to study the effect of formulation and processing techniques as well as to characterize the benefits of KinetiSol Dispersing for the production of solid dispersions. Preformulation studies were conducted using differential scanning calorimetry and hot stage microscopy to identify optimum carriers for the production of amorphous solid dispersions. After identification, solid dispersions were prepared by hot melt extrusion and KinetiSol Dispersing, with material characterized by X-ray diffraction, dissolution and potency testing to evaluate physicochemical properties. Results from the preformulation studies showed that vinylacetate:vinylpyrrolidone (PVPVA) copolymer allowed for hydrocortisone dissolution within the carrier at temperatures as low as 160 degrees C, while hydroxypropyl methylcellulose required temperatures upward of 180 degrees C to facilitate solubilization. Low substituted hydroxypropyl cellulose, a high glass transition temperature control, showed that the material was unable to solubilize hydrocortisone. Manufacturing process control studies using hot melt extruded compositions of hydrocortisone and PVPVA showed that increased temperatures and residence times negatively impacted product potency due to decomposition. Using KinetiSol Dispersing to reduce residence time and to facilitate lower temperature processing, it was possible to produce solid dispersions with improved product potency. This study clearly demonstrated the importance of carrier selection to facilitate lower temperature processing, as well as the effect of residence time on product potency. Furthermore, KinetiSol Dispersing provided significant advantages over hot melt extrusion due to the reduced

  16. Inhibitory effects of sesquiterpenes from bay leaf on nitric oxide production in lipopolysaccharide-activated macrophages: structure requirement and role of heat shock protein induction.

    PubMed

    Matsuda, H; Kagerura, T; Toguchida, I; Ueda, H; Morikawa, T; Yoshikawa, M

    2000-04-21

    The methanolic extract from the leaves of Laurus nobilis (bay leaf, laurel) was found to inhibit nitric oxide (NO) production in lipopolysaccharide (LPS)-activated mouse peritoneal macrophages. Through bioassay-guided separation, fourteen known sesquiterpenes were isolated from the active fraction and were examined for ability to inhibit the NO production. Seven sesquiterpene lactones (costunolide, dehydrocostus lactone, eremanthine, zaluzanin C, magnolialide, santamarine and spirafolide) potently inhibited LPS-induced NO production (IC50 = 1.2 approximately 3.8 microM). Other sesquiterpene constituents also showed the inhibitory activity (IC50 > or = 21 microM), but their inhibitory activities were less than those of sesquiterpene lactones. Alpha-methylene-gamma-butyrolactone also showed inhibitory activity (IC50 = 9.6 microM), while mokko lactone and watsonol A etc., reductants of the alpha-methylene-gamma-butyrolactone moiety by NaBH4 or DIBAL, and a 2-mercaptoethanol adduct of dehydrocostus lactone showed little activity (IC50 > or = 18 microM). These results indicated that the alpha-methylene-gamma-butyrolactone moiety is important for the activity. Furthermore, costunolide and dehydrocostus lactone inhibited inducible nitric oxide synthase (iNOS) induction in accordance with induction of heat shock protein 72 (HSP 72). These results suggested that, as one of their mechanisms of action, sesquiterpene lactones induce HSP 72 thereby preventing nuclear factor-kappaB activation followed by iNOS induction.

  17. Activation heat, activation metabolism and tension-related heat in frog semitendinosus muscles

    PubMed Central

    Homsher, E.; Mommaerts, W. F. H. M.; Ricchiuti, N. V.; Wallner, A.

    1972-01-01

    1. Frog semitendinosus muscles were stretched to various lengths beyond the rest length (l0) and their initial heat and isometric tension production were measured. 2. As the overlap between the thick and thin filaments is reduced, the initial twitch heat and tension decline in a linear manner. At a point at which the twitch tension approaches zero, the initial heat is 30% of that seen at l0. It is concluded that this heat is the activation heat and reflects the energetics of calcium release and reaccumulation. The initial heat at shorter sarcomere lengths appears to be the sum of the activation heat plus a heat production associated with the interaction of the thick and thin filaments. 3. A similar relationship between heat and tension production is seen in tetanic contractions. 4. The time course of activation heat production in a twitch can be resolved into two phases: a temperature insensitive (Q10 < 1·3) `fast' phase (with a time constant of 45 msec) and a temperature sensitive (Q10 = 2·8) `slow' phase (with a time constant of 330 msec at 0° C). 5. Measurements of the creatine phosphate (PC) hydrolysis by muscles contracting isometrically at various muscle lengths at and beyond l0, indicate an enthalpy change of -11·2 kcal/mole PC hydrolysed. The enthalpy change for the ATP hydrolysis by muscles stretched so that little or no tension was produced with stimulation was -9·9 kcal/mole ATP hydrolysed. It is concluded that the net activation heat is produced by the hydrolysis of PC or ATP. PMID:4536938

  18. Heat production by sediment: ecological significance

    SciTech Connect

    Pamatmat, M.M.

    1982-01-22

    Sediments held at constant temperature evolve heat at rates that can be measured by direct calorimetry. The heat production rates decrease with depth from the surface layer. Total heat flux is an indication of the rate of degradation of potential chemical energy originally fixed by photosynthesis and represents benthic energy flow.

  19. Fractal behavior in continental crustal heat production

    NASA Astrophysics Data System (ADS)

    Vedanti, N.; Srivastava, R. P.; Pandey, O. P.; Dimri, V. P.

    2011-02-01

    The distribution of crustal heat production, which is the most important component in the elucidation of continental thermal structure, still remains a theoretical assumption. In general the heat production values must decrease with depth, but the form of decrease of heat production in the crust is not well understood. The commonly used heat production models are: "block model", in which heat production is constant from the surface to a given depth and the "exponential model", in which heat production diminishes as an exponential function of depth. The exponential model is more widely used wherein sources of the errors are heterogeneity of rock and long wavelength changes due to changes in lithology and tectonic elements, and as such exponential distribution does not work satisfactorily for the entire crust. In the present study, we analyze for the first time, deep crustal heat production data of six global areas namely Dharwar craton (India), Kaapvaal craton (South Africa), Baltic shield (Kola, Russia), Hidaka metamorphic belt (Japan), Nissho pluton (Japan) and Continental Deep Drilling site (KTB, Germany). The power spectrum of all the studied data sets exhibits power law behaviour. This would mean slower decay of heat production with depth, which conforms to the known geologic composition of the crust. Minimum value of the scaling exponent has been found for the KTB borehole, which is apparently related to higher heat production of gneisses, however for other study areas, scaling exponent is almost similar. We also found that the lower values of scaling exponents are related to higher heat production in the crust as is the case in KTB. Present finding has a direct relevance in computation of temperature-depth profiles in continental regions.

  20. Cascade heat recovery with coproduct gas production

    DOEpatents

    Brown, William R.; Cassano, Anthony A.; Dunbobbin, Brian R.; Rao, Pradip; Erickson, Donald C.

    1986-01-01

    A process for the integration of a chemical absorption separation of oxygen and nitrogen from air with a combustion process is set forth wherein excess temperature availability from the combustion process is more effectively utilized to desorb oxygen product from the absorbent and then the sensible heat and absorption reaction heat is further utilized to produce a high temperature process stream. The oxygen may be utilized to enrich the combustion process wherein the high temperature heat for desorption is conducted in a heat exchange preferably performed with a pressure differential of less than 10 atmospheres which provides considerable flexibility in the heat exchange.

  1. Cascade heat recovery with coproduct gas production

    DOEpatents

    Brown, W.R.; Cassano, A.A.; Dunbobbin, B.R.; Rao, P.; Erickson, D.C.

    1986-10-14

    A process for the integration of a chemical absorption separation of oxygen and nitrogen from air with a combustion process is set forth wherein excess temperature availability from the combustion process is more effectively utilized to desorb oxygen product from the absorbent and then the sensible heat and absorption reaction heat is further utilized to produce a high temperature process stream. The oxygen may be utilized to enrich the combustion process wherein the high temperature heat for desorption is conducted in a heat exchange preferably performed with a pressure differential of less than 10 atmospheres which provides considerable flexibility in the heat exchange. 4 figs.

  2. Heating production fluids in a wellbore

    DOEpatents

    Orrego, Yamila; Jankowski, Todd A.

    2016-07-12

    A method for heating a production fluid in a wellbore. The method can include heating, using a packer fluid, a working fluid flowing through a first medium disposed in a first section of the wellbore, where the first medium transfers heat from the packer fluid to the working fluid. The method can also include circulating the working fluid into a second section of the wellbore through a second medium, where the second medium transfers heat from the working fluid to the production fluid. The method can further include returning the working fluid to the first section of the wellbore through the first medium.

  3. Heat Production as a Tool in Geothermal Exploration

    NASA Astrophysics Data System (ADS)

    Rhodes, J. M.; Koteas, C.; Mabee, S. B.; Thomas, M.; Gagnon, T.

    2012-12-01

    Heat flow data (together with knowledge, or assumptions, of stratigraphy, thermal conductivity and heat production) provide the prime parameter for estimating the potential of geothermal resources. Unfortunately this information is expensive to obtain as it requires deep boreholes. Consequently it is sparse or lacking in areas not traditionally considered as having geothermal potential. New England (and most of the northeastern U.S.A.) is one such area. However, in the absence of volcano-derived hydrothermal activity with its attendant high heat flow, granitic plutons provide an alternative geothermal resource. Compared with other crustal rocks, granites contain higher concentrations of heat-producing elements (K, U, Th). Additionally, they are relatively homogeneous, compared to surrounding country rock, allowing for stimulation through hydro-fracking of large (>1 km3) geothermal reservoirs. Consequently we have adopted a different approach, obtaining heat production data rather then relying on the very sparse heat flow data. Birch and colleagues long since recognized the relationship between heat flow and heat production as an integral part of their concept of Heat Flow Provinces. Heat production is readily determined in the laboratory by measuring the density of a sample and the concentrations of its heat-producing elements potassium, uranium and thorium. We have determined the heat production for 570 samples from most of the major granitic and gneissic bodies in Massachusetts and Connecticut. We have also measured these parameters for 70 sedimentary rocks that cover granites and gneiss in the Connecticut and Narragansett Basins. This data is being used to calculate inferred heat flow data for these localities. Comparison of these inferred heat flow values with the sparse number of those measured directly in boreholes in the two States is encouraging, indicating that this approach has merit. We have also measured thermal conductivity on all of these samples

  4. Heat and moisture production of modern swine

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The heat and moisture production (HP and MP) values that are currently published in the American Society of Heating, Refrigeration, and Air-Conditioning Engineers (ASHRAE) standards are from data collected in either the 1970’s (nursery piglets) or the 1950’s (growing-finishing pigs). This series of ...

  5. Universal constant for heat production in protists.

    PubMed

    Johnson, Matthew D; Völker, Jens; Moeller, Holly V; Laws, Edward; Breslauer, Kenneth J; Falkowski, Paul G

    2009-04-21

    Using a high sensitivity differential scanning calorimeter in isothermal mode, we directly measured heat production in eukaryotic protists from 5 phyla spanning over 5 orders of magnitude in carbon biomass and 8 orders of magnitude in cell volume. Our results reveal that metabolic heat production normalized to cell mass is virtually constant in these organisms, with a median of 0.037 pW pg C(-1) (95% confidence interval = 0.022-0.061 pW pg C(-1)) at 5 degrees C. Contrary to allometric models, the relationship between heat production and cell carbon content or surface area is isometric (scaling exponents, 1.056 and 1.057, respectively). That heat production per unit cell surface area is constant suggests that heat flux through the cell surface is effectively instantaneous, and hence that cells are isothermal with their environment. The results further suggest that allometric models of metabolism based on metazoans are not applicable to protists, and that the underlying metabolic processes in the latter polyphyletic group are highly constrained by evolutionary selection. We propose that the evolutionary constraint leading to a universally constant heat production in single-celled eukaryotes is related to cytoplasmic packaging of organelles and surface area to volume relationships controlling diffusion of resources to these organelles.

  6. Arkoma exploration heats production builds

    SciTech Connect

    Petzet, G.A.

    1991-01-21

    This paper reports that exploratory drilling continues with fervor to Cambro-Ordovician Arbuckle targets, especially in Arkansas. Pennsylvanian zones continue to yield significant gas discoveries. Gas production from Arkoma basin counties in both states has been rising and stands to climb even further with startup of several new pipelines, assuming gas prices and takes hold up.

  7. Market assessment for active solar heating and cooling products. Category B: a survey of decision-makers in the HVAC marketplace. Final report

    SciTech Connect

    1980-09-01

    A comprehensive evaluation of the market for solar heating and cooling products for new and retrofit markets is reported. The emphasis is on the analysis of solar knowledge among HVAC decision makers and a comprehensive evaluation of their solar attitudes and behavior. The data from each of the following sectors are described and analyzed: residential consumers, organizational and manufacturing buildings, HVAC engineers and architects, builders/developers, and commercial/institutional segments. (MHR)

  8. Combustion of horse manure for heat production.

    PubMed

    Lundgren, J; Pettersson, E

    2009-06-01

    The main objectives of this paper have been to evaluate the use of horse manure and wood-shavings as a fuel for heat production and to provide sets of data on the chemical composition, ash characteristics and ash forming elements of the fuel. Another objective has been to investigate the possibility to use the ash as fertiliser by analysing the heavy metal and nutrient contents. The results showed that the fuel is well suited for combustion for heat production causing low emissions of products of incomplete combustion. The emissions of NO(x) were however high due to the high content of fuel bound nitrogen. Emissions of CO and NO(x) were typically in the range of 30-150 mg/Nm(3) and 280-350 mg/Nm(3) at 10 vol% O(2), respectively. The analysis of the ash showed on sufficiently low concentration of heavy metals to allow recycling.

  9. Heat production during contraction in skeletal muscle of hypothyroid mice

    SciTech Connect

    Leijendekker, W.J.; van Hardeveld, C.; Elzinga, G. )

    1987-08-01

    The effect of hypothyroidism on tension-independent and -dependent heat produced during a twitch and a tetanic contraction of extensor digitorum longus (EDL) and soleus muscle of mice was examined. The amount of heat produced during a twitch and the rate of heat development during a tetanus of EDL and soleus were measured at and above optimal length. The effect of hypothyroidism on force production was <30%. Straight lines were used to fit the relation between heat production and force. Hypothyroidism significantly decreases tension-independent heat during contraction of EDL and soleus muscle. Because the tension-independent heat is considered to be related to the Ca{sup 2+} cycling, these findings suggest that ATP splitting due to the Ca{sup 2+} cycling is reduced in hypothyroid mice. This conclusion was strengthened by the observation that the oxalate-supported {sup 45}Ca{sup 2+}-uptake activity and {sup 45}Ca{sup 2+}-loading capacity of muscle homogenates from hypothyroid mice were reduced, respectively, to 51 and to 65% in soleus and to 63 and 73% in EDL muscle as compared with euthyroid mice. The tension-dependent rate of heat development during a tetanus was also decreased in soleus muscle of hypothyroid mice. This suggests a lower rate of ATP hydrolysis related to cross-bridge cycling in this muscle due to the hypothyroid state.

  10. Determinants of heat production in newborn lambs

    NASA Astrophysics Data System (ADS)

    Eales, F. A.; Small, J.

    1980-06-01

    Measurement of summit metabolism (the maximum rate of heat production) in lambs aged 1 or 4h revealed considerable between animal variation. Summit metabolism per unit body weight decreased as body weight increased whereas summit metabolism per unit body surface area was independent of body weight. Severe pre-partum hypoxia was apparently associated with a low summit metabolism at 1 or 4h of age which made such lambs very susceptible to hypothermia. This deficiency in heat production capacity did not appear to be a permanent featuresince most lambs so affected recovered full thermoregulatory ability by 12h of age. Feeding of colostrum conferred an immediate 18% increase in summit metabolism. The significance of these findings to the prevention of hypothermia in the newborn lamb is discussed.

  11. Gap between active and passive solar heating

    SciTech Connect

    Balcomb, J.D.

    1985-01-01

    The gap between active and passive solar could hardly be wider. The reasons for this are discussed and advantages to narrowing the gap are analyzed. Ten years of experience in both active and passive systems are reviewed, including costs, frequent problems, performance prediction, performance modeling, monitoring, and cooling concerns. Trends are analyzed, both for solar space heating and for service water heating. A tendency for the active and passive technologies to be converging is observed. Several recommendations for narrowing the gap are presented.

  12. Heat-activated heat-pump development and potential application of Stirling-engine technology

    NASA Astrophysics Data System (ADS)

    Fairchild, P. D.; West, C. D.

    1982-06-01

    Presented is a brief overview of the heat-activated heat pump technology development program being carried out with emphasis on the Stirling engine technology projects. The major projects are reviewed as they were formulated and carried out under the previous product development guidelines. The revised technology development focus and current status of those major hardware projects are discussed. The key issues involved in applying Stirling engine technology to heat pump equipment are assessed. The approach and planned future activities to address those issues are described. Also included are brief descriptions of two projects in this area supported by the Gas Research Institute.

  13. Dual Active Surface Heat Flux Gage Probe

    NASA Technical Reports Server (NTRS)

    Liebert, Curt H.; Kolodziej, Paul

    1995-01-01

    A unique plug-type heat flux gage probe was tested in the NASA Ames Research Center 2x9 turbulent flow duct facility. The probe was fabricated by welding a miniature dual active surface heat flux gage body to the end of a hollow metal cylindrical bolt containing a metal inner tube. Cooling air flows through the inner tube, impinges onto the back of the gage body and then flows out through the annulus formed between the inner tube and the hollow bolt wall. Heat flux was generated in the duct facility with a Huels arc heater. The duct had a rectangular cross section and one wall was fabricated from 2.54 centimeter thick thermal insulation rigid surface material mounted onto an aluminum plate. To measure heat flux, the probe was inserted through the plate and insulating materials with the from of the gage located flush with the hot gas-side insulation surface. Absorbed heat fluxes measured with the probe were compared with absorbed heat fluxes measured with six water-cooled reference calorimeters. These calorimeters were located in a water-cooled metal duct wall which was located across from the probe position. Correspondence of transient and steady heat fluxes measured with the reference calorimeters and heat flux gage probe was generally within a satisfactory plus or minus 10 percent. This good correspondence was achieved even though the much cooler probe caused a large surface temperature disruption of 1000K between the metal gage and the insulation. However, this temperature disruption did not seriously effect the accuracy of the heat flux measurement. A current application for dual active surface heat flux gages is for transient and steady absorbed heat flux, surface temperature and heat transfer coefficient measurements on the surface of an oxidizer turbine inlet deflector operating in a space shuttle test bed engine.

  14. Non-Heat Treatable Alloy Sheet Products

    SciTech Connect

    Hayden, H.W.; Barthold, G.W.; Das, S.K.

    1999-08-01

    ALCAR is an innovative approach for conducting multi-company, pre-competitive research and development programs. ALCAR has been formed to crate a partnership of aluminum producers, the American Society of Mechanical Engineers Center for Research and Technology Development (ASME/CRTD), the United States Department of Energy (USDOE), three USDOE National Laboratories, and a Technical Advisory Committee for conducting cooperative, pre-competitive research on the development of flower-cost, non-heat treated (NHT) aluminum alloys for automotive sheet applications with strength, formability and surface appearance similar to current heat treated (HT) aluminum alloys under consideration. The effort has been supported by the USDOE, Office of Transportation Technology (OTT) through a three-year program with 50/50 cost share at a total program cost of $3 million. The program has led to the development of new and modified 5000 series aluminum ally compositions. Pilot production-size ingots have bee n melted, cast, hot rolled and cold rolled. Stamping trials on samples of rolled product for demonstrating production of typical automotive components have been successful.

  15. Production Systems. Laboratory Activities.

    ERIC Educational Resources Information Center

    Gallaway, Ann, Ed.

    This production systems guide provides teachers with learning activities for secondary students. Introductory materials include an instructional planning outline and worksheet, an outline of essential elements, domains and objectives, a course description, and a content outline. The guide contains 30 modules on the following topics: production…

  16. In Situ Production of Fe-TiC Nanocomposite by Mechanical Activation and Heat Treatment of the Fe2O3/TiO2/C Powder

    NASA Astrophysics Data System (ADS)

    Moradi Ghiasabadi, Sara; Raygan, Shahram

    2012-11-01

    In this study, Fe-TiC nanocomposite was synthesized by carbothermic reduction of activated Fe2O3, TiO2, and graphite powder mixture. The effect of 0, 5, and 20 h of high energy ball milling of mixture on the reduction process was also investigated. Comparing the results of the thermogravimetry analysis of milled and un-milled mixtures clearly showed that the reduction temperature decreased due to the milling process. XRD pattern of 20 h milled powder mixture proved that Fe-TiC nanocomposite was formed after the heat treatment of activated powder at 1100°C for 1 h under vacuum. The microstructure studies of the milled mixture by scanning electron microscope revealed homogenous distribution of TiC particles in the Fe matrix.

  17. Mutagenicity of the products obtained from heated milk systems.

    PubMed

    Rogers, A M; Shibamoto, T

    1982-06-01

    Methylene chloride extracts of the browning reaction products prepared from model systems consisting of major milk components (casein and/or lactose, and non-fat dried milk) were tested for mutagenicity in the Ames Salmonella/microsome assay. Samples obtained by heating aqueous solutions of these components under either neutral or basic (pH 10) conditions exhibited no significant mutagenic activity when tested with or without S-9 mix. The addition of common food additives, such as sodium nitrite, butylated hydroxyanisole and butylated hydroxytoluene, to the aqueous solutions did not enhance the mutagenic activity of the browning samples. On the other hand, the tar samples prepared by heating the same milk components in the dry state exhibited strong mutagenicity, primarily to Salmonella typhimurium strain TA98 and only with S-9 mix. A casein/lactose mixture and non-fat dried milk were also heated with baking soda in the dry state. The presence of the baking soda enhanced the mutagenicity of the browning products; the tar from the non-fat dried milk heated with baking soda was the most potently mutagenic of all the samples towards strain TA98 and also produced a positive response in strain TA100 in the presence of S-9 mix. PMID:7201951

  18. Mutagenicity of the products obtained from heated milk systems.

    PubMed

    Rogers, A M; Shibamoto, T

    1982-06-01

    Methylene chloride extracts of the browning reaction products prepared from model systems consisting of major milk components (casein and/or lactose, and non-fat dried milk) were tested for mutagenicity in the Ames Salmonella/microsome assay. Samples obtained by heating aqueous solutions of these components under either neutral or basic (pH 10) conditions exhibited no significant mutagenic activity when tested with or without S-9 mix. The addition of common food additives, such as sodium nitrite, butylated hydroxyanisole and butylated hydroxytoluene, to the aqueous solutions did not enhance the mutagenic activity of the browning samples. On the other hand, the tar samples prepared by heating the same milk components in the dry state exhibited strong mutagenicity, primarily to Salmonella typhimurium strain TA98 and only with S-9 mix. A casein/lactose mixture and non-fat dried milk were also heated with baking soda in the dry state. The presence of the baking soda enhanced the mutagenicity of the browning products; the tar from the non-fat dried milk heated with baking soda was the most potently mutagenic of all the samples towards strain TA98 and also produced a positive response in strain TA100 in the presence of S-9 mix.

  19. Heat dissipation guides activation in signaling proteins

    PubMed Central

    Weber, Jeffrey K.; Shukla, Diwakar; Pande, Vijay S.

    2015-01-01

    Life is fundamentally a nonequilibrium phenomenon. At the expense of dissipated energy, living things perform irreversible processes that allow them to propagate and reproduce. Within cells, evolution has designed nanoscale machines to do meaningful work with energy harnessed from a continuous flux of heat and particles. As dictated by the Second Law of Thermodynamics and its fluctuation theorem corollaries, irreversibility in nonequilibrium processes can be quantified in terms of how much entropy such dynamics produce. In this work, we seek to address a fundamental question linking biology and nonequilibrium physics: can the evolved dissipative pathways that facilitate biomolecular function be identified by their extent of entropy production in general relaxation processes? We here synthesize massive molecular dynamics simulations, Markov state models (MSMs), and nonequilibrium statistical mechanical theory to probe dissipation in two key classes of signaling proteins: kinases and G-protein–coupled receptors (GPCRs). Applying machinery from large deviation theory, we use MSMs constructed from protein simulations to generate dynamics conforming to positive levels of entropy production. We note the emergence of an array of peaks in the dynamical response (transient analogs of phase transitions) that draw the proteins between distinct levels of dissipation, and we see that the binding of ATP and agonist molecules modifies the observed dissipative landscapes. Overall, we find that dissipation is tightly coupled to activation in these signaling systems: dominant entropy-producing trajectories become localized near important barriers along known biological activation pathways. We go on to classify an array of equilibrium and nonequilibrium molecular switches that harmonize to promote functional dynamics. PMID:26240354

  20. Heat production in an Archean crustal profile and implications for heat flow and mobilization of heat-producing elements

    NASA Technical Reports Server (NTRS)

    Ashwal, L. D.; Morgan, P.; Kelley, S. A.; Percival, J. A.

    1987-01-01

    Concentrations of heat producing elements (Th, U, and K) in 58 samples representative of the main lithologies in a 100-km transect of the Superior Province of the Canadian Shield have been obtained. The relatively large variation in heat production found among the silicic plutonic rocks is shown to correlate with modal abundances of accessory minerals, and these variations are interpreted as premetamorphic. The present data suggest fundamental differences in crustal radioactivity distributions between granitic and more mafic terrains, and indicate that a previously determined apparently linear heat flow-heat production relationship for the Kapuskasing area does not relate to the distribution of heat production with depth.

  1. Short-term heating reduces the anti-inflammatory effects of fresh raw garlic extracts on the LPS-induced production of NO and pro-inflammatory cytokines by downregulating allicin activity in RAW 264.7 macrophages.

    PubMed

    Shin, Jung-Hye; Ryu, Ji Hyeon; Kang, Min Jung; Hwang, Cho Rong; Han, Jaehee; Kang, Dawon

    2013-08-01

    Garlic has a variety of biologic activities, including anti-inflammatory properties. Although garlic has several biologic activities, some people dislike eating fresh raw garlic because of its strong taste and smell. Therefore, garlic formulations involving heating procedures have been developed. In this study, we investigated whether short-term heating affects the anti-inflammatory properties of garlic. Fresh and heated raw garlic extracts (FRGE and HRGE) were prepared with incubation at 25 °C and 95 °C, respectively, for 2 h. Treatment with FRGE and HRGE significantly reduced the LPS-induced increase in the pro-inflammatory cytokine concentration (TNF-α, IL-1β, and IL-6) and NO through HO-1 upregulation in RAW 264.7 macrophages. The anti-inflammatory effect was greater in FRGE than in HRGE. The allicin concentration was higher in FRGE than in HRGE. Allicin treatment showed reduced production of pro-inflammatory cytokines and NO and increased HO-1 activity. The results show that the decrease in LPS-induced NO and pro-inflammatory cytokines in RAW 264.7 macrophages through HO-1 induction was greater for FRGE compared with HRGE. Additionally, the results indicate that allicin is responsible for the anti-inflammatory effect of FRGE. Our results suggest a potential therapeutic use of allicin in the treatment of chronic inflammatory disease.

  2. Antiviral activities of heated dolomite powder.

    PubMed

    Motoike, Koichi; Hirano, Shozo; Yamana, Hideaki; Onda, Tetsuhiko; Maeda, Takayoshi; Ito, Toshihiro; Hayakawa, Motozo

    2008-12-01

    The effect of the heating conditions of dolomite powder on its antiviral activity was studied against the H5N3 avian influenza virus. Calcium oxide (CaO) and magnesium oxide (MgO), obtained by the thermal decomposition of dolomite above 800 degrees C, were shown to have strong antiviral activity, but the effect was lessened when the heating temperature exceeded 1400 degrees C. Simultaneous measurement of the crystallite size suggested that the weakening of the activity was due to the considerable grain growth of the oxides. It was found that the presence of Mg in dolomite contributed to the deterrence of grain growth of the oxides during the heating process. Although both CaO and MgO exhibited strong antiviral activity, CaO had the stronger activity but quickly hydrated in the presence of water. On the other hand, the hydration of MgO took place gradually under the same conditions. Separate measurements using MgO and Mg(OH)2 revealed that MgO had a higher antiviral effect than Mg(OH)2. From the overall experiments, it was suggested that the strong antiviral activity of dolomite was related to the hydration reaction of CaO. PMID:19127652

  3. Induction heat treatment as a means of increasing production

    SciTech Connect

    Golovin, G.F.; Shamov, A.N.

    1988-01-01

    The economic effectiveness of induction heat treatment was determined by a number of factors, including: saving energy and resources by substituting surface hardening for bulk or casehardening, improving labor productivity by process automation and including induction heat treatment equipment in the production line. Induction heating was found to be quick, does not require protection from oxidation, makes it possible to mechanize and automate the production process, and improves stabilization properties after annealing.

  4. Technologies for Production of Heat and Electricity

    SciTech Connect

    Jacob J. Jacobson; Kara G. Cafferty

    2014-04-01

    Biomass is a desirable source of energy because it is renewable, sustainable, widely available throughout the world, and amenable to conversion. Biomass is composed of cellulose, hemicellulose, and lignin components. Cellulose is generally the dominant fraction, representing about 40 to 50% of the material by weight, with hemicellulose representing 20 to 50% of the material, and lignin making up the remaining portion [4,5,6]. Although the outward appearance of the various forms of cellulosic biomass, such as wood, grass, municipal solid waste (MSW), or agricultural residues, is different, all of these materials have a similar cellulosic composition. Elementally, however, biomass varies considerably, thereby presenting technical challenges at virtually every phase of its conversion to useful energy forms and products. Despite the variances among cellulosic sources, there are a variety of technologies for converting biomass into energy. These technologies are generally divided into two groups: biochemical (biological-based) and thermochemical (heat-based) conversion processes. This chapter reviews the specific technologies that can be used to convert biomass to energy. Each technology review includes the description of the process, and the positive and negative aspects.

  5. Future crop production threatened by extreme heat

    NASA Astrophysics Data System (ADS)

    Siebert, Stefan; Ewert, Frank

    2014-04-01

    Heat is considered to be a major stress limiting crop growth and yields. While important findings on the impact of heat on crop yield have been made based on experiments in controlled environments, little is known about the effects under field conditions at larger scales. The study of Deryng et al (2014 Global crop yield response to extreme heat stress under multiple climate change futures Environ. Res. Lett. 9 034011), analysing the impact of heat stress on maize, spring wheat and soya bean under climate change, represents an important contribution to this emerging research field. Uncertainties in the occurrence of heat stress under field conditions, plant responses to heat and appropriate adaptation measures still need further investigation.

  6. Adapting poultry production to solar heat

    SciTech Connect

    Not Available

    1982-12-15

    During 1982 a floor heating system has been installed in a 40 ft. x 300 ft. chicken house (15,000 birds). The floor heating system consists of EPDM synthetic rubber tubing buried in a 4-inch concrete slab. Hot water is supplied to the tubing from a 4000 gallon storage tank which is insulated and buried outside the chicken house. The storage tank is heated by 24 solar collectors which are ground mounted on the south side of the chicken house. A propane fired boiler is in line between the storage tank and the floor. The boiler adds heat to the water entering the floor if the water is not hot enough.

  7. Market assessment for active solar heating and cooling products. Category B: A survey of decision makers in the HVAC market place. Survey instruments

    SciTech Connect

    Lilien, G. L.; Johnston, P. E.

    1980-09-01

    Telephone screener questionnaires and mail-out questionnaires for marketing surveys for solar heating and cooling equipment are presented. Questionnaires are included for the residential segment, industrial segment, HVAC professionals segment, builder/developer segment, and the commercial segment. No results are reported. (WHK)

  8. Heat flow-heat production relationship not found: what drives heat flow variability of the Western Canadian foreland basin?

    NASA Astrophysics Data System (ADS)

    Majorowicz, Jacek A.

    2016-06-01

    Heat flow high -80 ± 10 mW/m2 in the northern western parts of the Western Canadian foreland basin is in large contrast to low heat flow to the south and east (50 ± 7 mW/m2) of the same basin with the same old 2E09 year's Precambrian basement and some 200-km-thick lithosphere. Over-thrusted and flat-laying sedimentary units are heated from below by heat flow from the old craton' crust and low 15 ± 5 mW/m2 mantle contribution. The heat flow vs. radiogenic heat production statistical relationship is not found for this area. To account for this large heat flow contrast and to have 200-km-thick lithosphere, we would need to assume that high heat production layer of the upper crust varies in thickness as much as factor of 2 and/or that the measured heat production at top of Precambrian basement is not representative for deeper rocks. The other explanation proposed before that heat in the basin is redistributed by the regional fluid flow systems driven from high hydraulic head areas close to the foothills of the Rocky Mountains toward low elevation areas to the east and north cannot be explained by observed low Darcy fluid velocities and the geometry of the basin.

  9. Heat production by single fibres of frog muscle.

    PubMed

    Curtin, N A; Howarth, J V; Woledge, R C

    1983-04-01

    The heat produced during contractions of preparations consisting of one or a few muscle fibres was measured for the first time. Fibres were dissected from the anterior tibialis muscles of the frog, Rana temporaria. Measurements were made with thermopiles of a design based on that described by Howarth et al. (1975). Although the fibre preparations were small, measurable signals could be recorded because the heat capacity of the thermopiles was also small. The output of the thermopile was amplified by a galvanometer circuit. In all the experiments the ends of the preparation were held in a fixed position during stimulation ("isometric'). Observations were made of heat production during twitches and tetanic contractions. The heat produced in a twitch of a single fibre depended on the stimulus strength in an all-or-nothing way. The results show that the amount of heat produced in individual twitches is fairly constant at different temperatures in the range 3-15 degrees C. In contrast, the heat produced in tetanic contractions is considerably greater at higher temperatures. The time course of heat production in a tetanus was influenced by temperature such that the early rapid phase of heat production was less obvious at the higher temperature. The quantities of heat produced by fibre preparations were in reasonable agreement with those produced by whole muscles when the comparison was made on the basis of heat produced per g wet weight of tissue. PMID:6602811

  10. RF heating for fusion product studies

    SciTech Connect

    Hellsten, T. Johnson, T.; Sharapov, S. E.; Kiptily, V.; Rimini, F.; Eriksson, J.; Mantsinen, M.; Schneider, M.; Tsalas, M.

    2015-12-10

    Third harmonic cyclotron heating is an effective tool for accelerating deuterium (D) beams to the MeV energy range, suitable for studying ITER relevant fast particle physics in plasmas without significant tritium content. Such experiments were recently conducted in JET with an ITER like wall in D plasmas with {sup 3}He concentrations up to 30% in order to boost the fusion reactivity by D-{sup 3}He reactions. The harmonic cyclotron heating produces high-energy tails in the MeV range of D ions by on-axis heating and of {sup 3}He ions by tangential off-axis heating. The discharges are characterized by long sawtooth free periods and a rich spectrum of MHD modes excited by the fast D and {sup 3}He ions. The partitions of the power, which depend on the distribution function of D, vary strongly over several slowing down times. Self-consistent modelling of the distribution function with the SELFO-light code are presented and compared with experimental data from fast particle diagnostics.

  11. RF heating for fusion product studies

    NASA Astrophysics Data System (ADS)

    Hellsten, T.; Johnson, T.; Sharapov, S. E.; Kiptily, V.; Eriksson, J.; Mantsinen, M.; Schneider, M.; Rimini, F.; Tsalas, M.

    2015-12-01

    Third harmonic cyclotron heating is an effective tool for accelerating deuterium (D) beams to the MeV energy range, suitable for studying ITER relevant fast particle physics in plasmas without significant tritium content. Such experiments were recently conducted in JET with an ITER like wall in D plasmas with 3He concentrations up to 30% in order to boost the fusion reactivity by D-3He reactions. The harmonic cyclotron heating produces high-energy tails in the MeV range of D ions by on-axis heating and of 3He ions by tangential off-axis heating. The discharges are characterized by long sawtooth free periods and a rich spectrum of MHD modes excited by the fast D and 3He ions. The partitions of the power, which depend on the distribution function of D, vary strongly over several slowing down times. Self-consistent modelling of the distribution function with the SELFO-light code are presented and compared with experimental data from fast particle diagnostics.

  12. Latent heat thermal energy storage for lunar oxygen production

    SciTech Connect

    Solomon, A.D.; Alexiades, V.; Jacobs, G.; Naney, M.; Olszewski, M.

    1992-08-01

    A necessary component of a solar-based lunar oxygen production system is a thermal energy storage module. We discuss some of the heat transfer and phase change problems associated with the design and operation of such a module based on the latent heat of melting of lunar rock. 12 refs.

  13. Latent heat thermal energy storage for lunar oxygen production

    SciTech Connect

    Solomon, A.D. , Omer ); Alexiades, V.; Jacobs, G.; Naney, M.; Olszewski, M. )

    1992-01-01

    A necessary component of a solar-based lunar oxygen production system is a thermal energy storage module. We discuss some of the heat transfer and phase change problems associated with the design and operation of such a module based on the latent heat of melting of lunar rock. 12 refs.

  14. Rubisco activase and wheat productivity under heat stress conditions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rubisco activase (RCA) constrains the photosynthetic potential of plants at high temperature (heat stress). We hypothesized that endogenous levels of RCA could serve as an important determinant of plant productivity under heat stress conditions. In this study, we investigated the possible relation...

  15. Heat Pipe Solar Receiver for Oxygen Production of Lunar Regolith

    NASA Astrophysics Data System (ADS)

    Hartenstine, John R.; Anderson, William G.; Walker, Kara L.; Ellis, Michael C.

    2009-03-01

    A heat pipe solar receiver operating in the 1050° C range is proposed for use in the hydrogen reduction process for the extraction of oxygen from the lunar soil. The heat pipe solar receiver is designed to accept, isothermalize and transfer solar thermal energy to reactors for oxygen production. This increases the available area for heat transfer, and increases throughput and efficiency. The heat pipe uses sodium as the working fluid, and Haynes 230 as the heat pipe envelope material. Initial design requirements have been established for the heat pipe solar receiver design based on information from the NASA In-Situ Resource Utilization (ISRU) program. Multiple heat pipe solar receiver designs were evaluated based on thermal performance, temperature uniformity, and integration with the solar concentrator and the regolith reactor(s). Two designs were selected based on these criteria: an annular heat pipe contained within the regolith reactor and an annular heat pipe with a remote location for the reactor. Additional design concepts have been developed that would use a single concentrator with a single solar receiver to supply and regulate power to multiple reactors. These designs use variable conductance or pressure controlled heat pipes for passive power distribution management between reactors. Following the design study, a demonstration heat pipe solar receiver was fabricated and tested. Test results demonstrated near uniform temperature on the outer surface of the pipe, which will ultimately be in contact with the regolith reactor.

  16. Development and testing of heat transport fluids for use in active solar heating and cooling systems

    NASA Technical Reports Server (NTRS)

    Parker, J. C.

    1981-01-01

    Work on heat transport fluids for use with active solar heating and cooling systems is described. Program objectives and how they were accomplished including problems encountered during testing are discussed.

  17. NGNP Process Heat Applications: Hydrogen Production Accomplishments for FY2010

    SciTech Connect

    Charles V Park

    2011-01-01

    This report summarizes FY10 accomplishments of the Next Generation Nuclear Plant (NGNP) Engineering Process Heat Applications group in support of hydrogen production technology development. This organization is responsible for systems needed to transfer high temperature heat from a high temperature gas-cooled reactor (HTGR) reactor (being developed by the INL NGNP Project) to electric power generation and to potential industrial applications including the production of hydrogen.

  18. Commercial Product Activation Using RFID

    NASA Technical Reports Server (NTRS)

    Jedrey, Thomas

    2008-01-01

    Radio-frequency identification (RFID) would be used for commercial product activation, according to a proposal. What is new here is the concept of combining RFID with activation - more specifically, using RFID for activating commercial products (principally, electronic ones) and for performing such ancillary functions as tracking individual product units on production lines, tracking shipments, and updating inventories. According to the proposal, an RFID chip would be embedded in each product. The information encoded in the chip would include a unique number for identifying the product. An RFID reader at the point of sale would record the number of the product and would write digital information to the RFID chip for either immediate activation of the product or for later interrogation and processing. To be practical, an RFID product-activation system should satisfy a number of key requirements: the system should be designed to be integrable into the inventory-tracking and the data-processing and -communication infrastructures of businesses along the entire supply chain from manufacture to retail; the system should be resistant to sophisticated hacking; activation codes should be made sufficiently complexity to minimize the probability of activating stolen products; RFID activation equipment at points of sale must be capable to two-way RF communication for the purposes of reading information from, and writing information to, embedded RFID chips; the equipment at points of sale should be easily operable by sales clerks with little or no training; the point-of-sale equipment should verify activation and provide visible and/or audible signals indicating verification or lack thereof; and, the system should be able to handle millions of products per year with minimal human intervention, among other requirements.

  19. Method of heat treating a formed powder product material

    NASA Technical Reports Server (NTRS)

    Freche, J. C.; Waters, W. J.; Ashbrook, R. L. (Inventor)

    1973-01-01

    Heat treating a product material of prealloyed powders after shaping by superplastic deformation restores the ability of the material to resist deformation at high temperatures. Heat treating is accomplished by heating to a temperature between the solidus and liquidus with the application of isostatic pressure to close any voids. This pressure may be simultaneously applied while the material is at the heat treating temperature. The pressure may also be applied when the material cools to a temperature between that at which it is shaped and the solidus.

  20. Preliminary design activities for solar heating and cooling systems

    NASA Technical Reports Server (NTRS)

    1978-01-01

    Information on the development of solar heating and cooling systems is presented. The major emphasis is placed on program organization, system size definition, site identification, system approaches, heat pump and equipment design, collector procurement, and other preliminary design activities.

  1. Working in Australia's heat: health promotion concerns for health and productivity.

    PubMed

    Singh, Sudhvir; Hanna, Elizabeth G; Kjellstrom, Tord

    2015-06-01

    This exploratory study describes the experiences arising from exposure to extreme summer heat, and the related health protection and promotion issues for working people in Australia. Twenty key informants representing different industry types and occupational groups or activities in Australia provided semi-structured interviews concerning: (i) perceptions of workplace heat exposure in the industry they represented, (ii) reported impacts on health and productivity, as well as (iii) actions taken to reduce exposure or effects of environmental heat exposure. All interviewees reported that excessive heat exposure presents a significant challenge for their industry or activity. People working in physically demanding jobs in temperatures>35°C frequently develop symptoms, and working beyond heat tolerance is common. To avoid potentially dangerous health impacts they must either slow down or change their work habits. Such health-preserving actions result in lost work capacity. Approximately one-third of baseline work productivity can be lost in physically demanding jobs when working at 40°C. Employers and workers consider that heat exposure is a 'natural hazard' in Australia that cannot easily be avoided and so must be accommodated or managed. Among participants in this study, the locus of responsibility for coping with heat lay with the individual, rather than the employer. Heat exposure during Australian summers commonly results in adverse health effects and productivity losses, although quantification studies are lacking. Lack of understanding of the hazardous nature of heat exposure exacerbates the serious risk of heat stress, as entrenched attitudinal barriers hamper amelioration or effective management of this increasing occupational health threat. Educational programmes and workplace heat guidelines are required. Without intervention, climate change in hot countries, such as Australia, can be expected to further exacerbate heat-related burden of disease and loss

  2. Working in Australia's heat: health promotion concerns for health and productivity.

    PubMed

    Singh, Sudhvir; Hanna, Elizabeth G; Kjellstrom, Tord

    2015-06-01

    This exploratory study describes the experiences arising from exposure to extreme summer heat, and the related health protection and promotion issues for working people in Australia. Twenty key informants representing different industry types and occupational groups or activities in Australia provided semi-structured interviews concerning: (i) perceptions of workplace heat exposure in the industry they represented, (ii) reported impacts on health and productivity, as well as (iii) actions taken to reduce exposure or effects of environmental heat exposure. All interviewees reported that excessive heat exposure presents a significant challenge for their industry or activity. People working in physically demanding jobs in temperatures>35°C frequently develop symptoms, and working beyond heat tolerance is common. To avoid potentially dangerous health impacts they must either slow down or change their work habits. Such health-preserving actions result in lost work capacity. Approximately one-third of baseline work productivity can be lost in physically demanding jobs when working at 40°C. Employers and workers consider that heat exposure is a 'natural hazard' in Australia that cannot easily be avoided and so must be accommodated or managed. Among participants in this study, the locus of responsibility for coping with heat lay with the individual, rather than the employer. Heat exposure during Australian summers commonly results in adverse health effects and productivity losses, although quantification studies are lacking. Lack of understanding of the hazardous nature of heat exposure exacerbates the serious risk of heat stress, as entrenched attitudinal barriers hamper amelioration or effective management of this increasing occupational health threat. Educational programmes and workplace heat guidelines are required. Without intervention, climate change in hot countries, such as Australia, can be expected to further exacerbate heat-related burden of disease and loss

  3. Depressurization and electrical heating of hydrate sediment for gas production

    NASA Astrophysics Data System (ADS)

    Minagawa, H.

    2015-12-01

    As a part of a Japanese National hydrate research program (MH21, funded by METI), we performed a study on electrical heating of the hydrate core combined with depressurization for gas production. In-situ dissociation of natural gas hydrate is necessary for commercial recovery of natural gas from natural gas hydrate sediment. Thermal stimulation is an effective dissociation method, along with depressurization.To simulate methane gas production from methane hydrate layer, we investigated electrical heating of methane hydrate sediment. A decrease in core temperature due to the endothermic reaction of methane hydrate dissociation was suppressed and the core temperature increased between 1oC and 4oC above the control temperature with electric heating. A current density of 10A/m2 with depressurization would effectively dissociate hydrate. Therefore, depressurization and additional electrode heating of hydrate sediment saturated with electrolyte solution was confirmed to enable higher gas production from sediment with less electric power.

  4. Serum chemotactic inhibitory activity: heat activation of chemotactic inhibition.

    PubMed Central

    Epps, D E; Williams, R C

    1976-01-01

    Serum chemotactic inhibitory activity (CIA) was studied in 46 patients with various systemic diseases, using a system consisting of normal human leukocytes as indicator cells and 10% fresh normal serum as a control chemotactic attractant. It was shown, as previously reported, that an association exists between CIA and skin test anergy. Heat treatment of sera at 56 C for 30 min increased both the incidence and the degree of chemotactic inhibition observed in these patients. The effects of heat treatment of sera containing CIA on other chemotactic attractants (C3a, bacteria-derived chemotactic factor (BF), and casein) are shown. Before heat treatment, some sera suppressed chemotaxis mediated by BF in the absence of suppression of normal serum-mediated chemotaxis, indicating the possible involvement of more than one system of inhibition. Multiple systems were further supported by data indicating that room temperature incubation resulted in a loss of CIA as measured by normal serum-mediated chemotoxis with no apparent decrease in the inhibition of BF -mediated chemotaxis. Separation of sera containing CIA by Sephadex G-200 showed chemotactic inhibitory activity to be increased in both the void volume region. Experiments showed that heat treating before separation resulted in similar increases in both peaks, implying the presence of an antagonist to CIA. Experiments demonstrating that sera containing CIA do not suppress casein-mediated chemotaxis by means of an irreversible inactivation of chemotactic factor are included along with experiments demonstrating a cellular mode of action. The possible presence of two systems of chemotactic inhibition, one acting directly upon chemotactic factors and one interacting with the responding cell, are discussed. PMID:773824

  5. Low-power nuclear engineering for heat production

    NASA Astrophysics Data System (ADS)

    Kursky, A. S.; Kalygin, V. V.; Semidotsky, I. I.

    2012-05-01

    The paper shows the expediency and importance of the development of low-power nuclear engineering as well as feasibility indices of an up-to-date nuclear power plant intended for regional energy production. A high reliability of the vessel-type boiling reactor with a natural coolant circulation is shown under various operating conditions of a nuclear heat production plant.

  6. Heat stress causes substantial labour productivity loss in Australia

    NASA Astrophysics Data System (ADS)

    Zander, Kerstin K.; Botzen, Wouter J. W.; Oppermann, Elspeth; Kjellstrom, Tord; Garnett, Stephen T.

    2015-07-01

    Heat stress at the workplace is an occupational health hazard that reduces labour productivity. Assessment of productivity loss resulting from climate change has so far been based on physiological models of heat exposure. These models suggest productivity may decrease by 11-27% by 2080 in hot regions such as Asia and the Caribbean, and globally by up to 20% in hot months by 2050. Using an approach derived from health economics, we describe self-reported estimates of work absenteeism and reductions in work performance caused by heat in Australia during 2013/2014. We found that the annual costs were US$655 per person across a representative sample of 1,726 employed Australians. This represents an annual economic burden of around US$6.2 billion (95% CI: 5.2-7.3 billion) for the Australian workforce. This amounts to 0.33 to 0.47% of Australia’s GDP. Although this was a period when many Australians experienced what is at present considered exceptional heat, our results suggest that adaptation measures to reduce heat effects should be adopted widely if severe economic impacts from labour productivity loss are to be avoided if heat waves become as frequent as predicted.

  7. Light masking of circadian rhythms of heat production, heat loss, and body temperature in squirrel monkeys

    NASA Technical Reports Server (NTRS)

    Robinson, E. L.; Fuller, C. A.

    1999-01-01

    Whole body heat production (HP) and heat loss (HL) were examined to determine their relative contributions to light masking of the circadian rhythm in body temperature (Tb). Squirrel monkey metabolism (n = 6) was monitored by both indirect and direct calorimetry, with telemetered measurement of body temperature and activity. Feeding was also measured. Responses to an entraining light-dark (LD) cycle (LD 12:12) and a masking LD cycle (LD 2:2) were compared. HP and HL contributed to both the daily rhythm and the masking changes in Tb. All variables showed phase-dependent masking responses. Masking transients at L or D transitions were generally greater during subjective day; however, L masking resulted in sustained elevation of Tb, HP, and HL during subjective night. Parallel, apparently compensatory, changes of HL and HP suggest action by both the circadian timing system and light masking on Tb set point. Furthermore, transient HL increases during subjective night suggest that gain change may supplement set point regulation of Tb.

  8. United States Department of Energy Thermally Activated Heat Pump Program

    SciTech Connect

    Fiskum, R.J.; Adcock, P.W.; DeVault, R.C.

    1996-06-01

    The US Department of Energy (DOE) is working with partners from the gas heating and cooling industry to improve energy efficiency using advance absorption technologies, to eliminate chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs), to reduce global warming through more efficient combustion of natural gas, and to impact electric peak demand of air conditioning. To assist industry in developing these gas heating and cooling absorption technologies, the US DOE sponsors the Thermally Activated Heat Pump Program. It is divided into five key activities, addressing residential gas absorption heat pumps, large commercial chillers, advanced absorption fluids, computer-aided design, and advanced ``Hi-Cool`` heat pumps.

  9. Ohmic heated sheet for the Ca ion beam production.

    PubMed

    Efremov, A; Bogomolov, S; Kazarinov, N; Kochagov, O; Loginov, V

    2008-02-01

    The production of intense accelerated (48)Ca ion beams is the key problem in the experiments on the synthesis of new superheavy nuclei. For this purpose in the FLNR (JINR), an electron cyclotron resonance ion source is used at the U-400 cyclotron. The combination of a micro oven with a hot tantalum sheet inside the discharge chamber allowed the production of the intense (48)Ca(5+) ion beam at the (48)Ca consumption of about 0.5 mg/h. In this case, the tantalum sheet is heated by microwaves and plasma electrons. The microwave power of up to 500 W is required to heat the sheet to the temperature of about 500 degrees C. To decrease the required microwave power, a new sheet with a direct Ohmic heating was designed. The present paper describes the method, technique, and preliminary experimental results on the production of the Ca ion beam.

  10. Heat-activated cooling devices: A guidebook for general audiences

    SciTech Connect

    Wiltsee, G.

    1994-02-01

    Heat-activated cooling is refrigeration or air conditioning driven by heat instead of electricity. A mill or processing facility can us its waste fuel to air condition its offices or plant; using waste fuel in this way can save money. The four basic types of heat-activated cooling systems available today are absorption cycle, desiccant system, steam jet ejector, and steam turbine drive. Each is discussed, along with cool storage and biomass boilers. Steps in determining the feasibility of heat-activated cooling are discussed, as are biomass conversion, system cost and integration, permits, and contractor selection. Case studies are given.

  11. Depressurization and electrical heating of hydrate sediment for gas production

    NASA Astrophysics Data System (ADS)

    Minagawa, H.; Ito, T.; Kimura, S.; Kaneko, H.; Noda, S.; Narita, H.

    2014-12-01

    In-situ dissociation of natural gas hydrate is necessary for commercial recovery of natural gas from natural gas hydrate sediment. Thermal stimulation is an effective dissociation method, along with depressurization. In this study, we examined the efficiency of electrical heating of the hydrate core for gas production. In order to evaluate efficiency of electrical heating with depressurization, we investigated following subject. (1) electrical heating of Xe gas hydrate sediment, as a conventional simulation of methane hydrate sediment, (2) electrical heating of methane hydrate sediment, which was compared with Xe gas hydrate experiment, and (3) electrical heating of hydrate bearing sediment with fine sandy layer which was simulated faults with large displacement shear around hydrate sediment. These experiments revealed that depressurization and additional electrode heating of hydrate sediment saturated with electrolyte solution was confirmed to enable higher efficient and effective gas production from sedimentwith less electric power. This study is financially supported by METI and Research Consortium for Methane Hydrate Resources in Japan (the MH21 Research Consortium).

  12. Antioxidants in heat-processed koji and the production mechanisms.

    PubMed

    Okutsu, Kayu; Yoshizaki, Yumiko; Ikeda, Natsumi; Kusano, Tatsuro; Hashimoto, Fumio; Takamine, Kazunori

    2015-11-15

    We previously developed antioxidative heat-processed (HP)-koji via two-step heating (55 °C/2days → 75 °C/3 days) of white-koji. In this study, we isolated antioxidants in HP-koji and investigated their formation mechanisms. The antioxidants were identified to be 5-hydroxymethyl furfural (HMF) and 5-(α-D-glucopyranosyloxymethyl)-2-furfural (GMF) based on nuclear magnetic resonance spectral analysis. HMF and GMF were not present in intact koji, but were formed by heating at 75 °C. As production of these antioxidants was more effective by two-step heating than by constant heating at 55 °C or 75 °C, we presumed that the antioxidant precursors are derived enzymatically at 55°C and that the antioxidants are formed subsequently by thermal reaction at 75 °C. The heating assay of saccharide solutions revealed glucose and isomaltose as HMF and GMF precursors, respectively, and thus the novel finding of GMF formation from isomaltose. Finally, HMF and GMF were effectively formed by two-step heating from glucose and isomaltose present in koji.

  13. New industrial heat pump applications to ethanol production

    SciTech Connect

    Not Available

    1990-04-01

    An energy cost reduction study of the Midwest Grain Products, Atchison, Kansas Beverage grade alcohol (from grain) and speciality starch plant has been completed. The objective was to find out effective energy cost reduction projects and to develop a coherent strategy for realizing the savings. There are many possible options for reducing energy cost. To facilitate a fair comparison of the options, Pinch Technology was used to identify appropriate heat recovery, heat pumping and cogeneration options. Of particular interest were the opportunities for utilizing heat pumps, for energy cost reduction or other profit increasing uses. Therefore, where a heat pumping scheme was identified, its merits relative to other potential projects was carefully evaluated to ensure that the heat pump was technically and economically sound. It is felt that the results obtained in this study are applicable to other alcohol plants, due to the similarity of processes throughout the industry. This study and others indicate that reductions in thermal energy consumption of 10--30% can be expected through increased heat recovery. Additional energy cost reductions can be achieved through the use of MVR evaporators and other heat pump systems. 16 figs., 3 tabs.

  14. Effects of gas bubble production on heat transfer from a volumetrically heated liquid pool

    NASA Astrophysics Data System (ADS)

    Bull, Geoffrey R.

    Aqueous solutions of uranium salts may provide a new supply chain to fill potential shortfalls in the availability of the most common radiopharmaceuticals currently in use worldwide, including Tc99m which is a decay product of Mo99. The fissioning of the uranium in these solutions creates Mo99 but also generates large amounts of hydrogen and oxygen from the radiolysis of the water. When the dissolved gases reach a critical concentration, bubbles will form in the solution. Bubbles in the solution affect both the fission power and the heat transfer out of the solution. As a result, for safety and production calculations, the effects of the bubbles on heat transfer must be understood. A high aspect ratio tank was constructed to simulate a section of an annulus with heat exchangers on the inner and outer steel walls to provide cooling. Temperature measurements via thermocouples inside the tank and along the outside of the steel walls allowed the calculation of overall and local heat transfer coefficients. Different air injection manifolds allowed the exploration of various bubble characteristics and patterns on heat transfer from the pool. The manifold type did not appear to have significant impact on the bubble size distributions in water. However, air injected into solutions of magnesium sulfate resulted in smaller bubble sizes and larger void fractions than those in water at the same injection rates. One dimensional calculations provide heat transfer coefficient values as functions of the superficial gas velocity in the pool.

  15. Differential heat stability of amphenicols characterized by structural degradation, mass spectrometry and antimicrobial activity.

    PubMed

    Franje, Catherine A; Chang, Shao-Kuang; Shyu, Ching-Lin; Davis, Jennifer L; Lee, Yan-Wen; Lee, Ren-Jye; Chang, Chao-Chin; Chou, Chi-Chung

    2010-12-01

    Heat stability of amphenicols and the relationship between structural degradation and antimicrobial activity after heating has not been well investigated. Florfenicol (FF), thiamphenicol (TAP), and chloramphenicol (CAP) were heated at 100 degrees C in water, salt water, soybean sauce and chicken meat for up to 2h. Degradation and antimicrobial activity of the compounds was evaluated using capillary electrophoresis (CE) with UV-DAD spectrometry, minimum inhibitory concentration (MIC) assay, and gas chromatography with electron impact ionization mass spectrometry (GC-EI-MS). Heat stability of amphenicols in matrices was ranked as water> or =salt water>soybean sauce>meat, suggesting that heat degradation of amphenicols was accelerated in soybean sauce and was not protected in meat. Heat stability by drug and matrices was ranked as FF>TAP=CAP in water, FF=TAP>CAP in salt water, TAP> or =FF=CAP in soybean sauce, and TAP> or =FF=CAP in meat, indicating differential heat stability of amphenicols among the 3 drugs and in different matrices. In accordance with the less than 20% degradation, the MIC against Escherichia coli and Staphylococcus aureus did not change after 2h heating in water. A 5-min heating of amphenicols in water by microwave oven generated comparable percentage degradation to boiling in water bath for 30 min to 1h. Both CE and GC-MS analysis showed that heating of FF produced TAP but not FF amine as one of its breakdown products. In conclusion, despite close similarity in structure; amphenicols exhibited differential behavior toward heating degradation in solutions and protein matrices. Although higher degradations of amphenicols were observed in soybean sauce and meat, heating treatment may generate product with antimicrobial activity (FF to TAP), therefore, heating of amphenicol residues in food cannot always be assumed safe.

  16. Stimulation of cysteinyl leukotriene production in mast cells by heat shock and acetylsalicylic acid.

    PubMed

    Mortaz, Esmaeil; Redegeld, Frank A; Dunsmore, Kathy; Odoms, Kelli; Wong, Hector R; Nijkamp, Frans P; Engels, Ferdi

    2007-04-30

    Immunoglobulin (Ig) E-dependent activation of mast cells is central to the allergic response. The engagement of IgE-occupied receptors initiates a series of molecular events that causes the release of preformed, and de novo synthesis of, allergic mediators. Cysteinyl leukotrienes are able to contract airway smooth muscle and increase mucus secretion and vascular permeability and recruit eosinophils. Mast cells have also recently been recognized as active participants in innate immune responses. Heat stress can modulate innate immunity by inducing stress proteins such as heat-shock proteins (HSPs). We previously demonstrated that treatment of mast cells with heat shock or acetylsalicylic acid results in an increase of TNF-alpha and IL-6 release. This effect was paralleled by expression of HSP70. In the current study, we further investigated the effects of heat shock and acetylsalicylic acid on the activation of mast cells and the release of cysteinyl leukotrienes. In mouse mast cells, derived from a culture of bone marrow cells, responsiveness to heat shock, acetylsalicylic acid and exogenous or endogenous HSP70 was monitored by measuring leukotriene C4 release. We show that after heat shock treatment and exposure to acetylsalicylic acid leukotriene production was increased. Moreover, exogenous rHSP70 also induced leukotriene production. Because it has been reported that leukotriene production in mast cells may be mediated by Toll like receptor (TLR) activation, and HSP70 also activates TLRs signaling, we further explored these issues by using mast cells that are not able to produce HSP70, i.e. heat shock factor-1 (HSF-1) knockout cells. We found that in HSF-1 knockout bone marrow derived mast cells, heat shock and acetylsalicylic acid failed to induce release of leukotrienes. Moreover, in wild type cells the surface expression of TLR4 was attenuated, whereas the intracellular expression was up-regulated. We conclude that heat shock and acetylsalicylic acid induce

  17. Mutagenic activity and heterocyclic amine content of heated foods

    SciTech Connect

    Knize, M.G.; Johansson, M.; Jones, A.L.; Blakley, M.; Felton, J.S.

    1994-12-31

    Cooked foods were extracted and analyzed for mutagenic activity and assayed for known heterocyclic amines (HAs) by the Ames/Salmonella test and HPLC, respectively. Fried meats contain HAs (predominantly PhIP, MeIQx, DiMeIQx, and A{alpha}C) that are potent promutagens in bacteria, mutagenic in cultured mammalian cells, and carcinogenic in rodents and in nonhuman primates. Meats contain levels ranging from undetectable (< 0.1 ppb) to 50 ppb of known HAs when fried at temperatures from 190 to 250{degrees}C. These identified compounds are responsible for ca 75% of the measured mutagenic activity in Salmonella strain TA98. Barbecued beef and chicken have up to several thousand TA98 revertants per gram (rev/g) of cooked meat, with only ca 30% of the mutagenic activity accounted for by known heterocyclic amines. Some heated nonmeat foods also contain potent mutagenic activity. Toasted breads, cereals and snack foods have 0 to 10 TA98 rev/g, but overtoasting yields up to 40 rev/g, wheat and gluten-containing products are associated with higher activity. Grain-based coffee-substitute powders and instant coffees have 190 to 380 rev/g in TA98, and 1100 to 4000 rev/g in strain YG1024. The identify of the compounds responsible for the mutagenic activity are unknown in these non-meat foods. Toasted grain-based foods probably contribute less than 10% of the total mutagenic activity of the diet, with meat products responsible for the reminder. The finding of varying amounts of known and unknown mutagens in some cooked foods may be responsible for the poorly understood variation in human cancer incidence worldwide.

  18. A heat-activated and thermoresistant telomerase activity in Leishmania major Friedlin.

    PubMed

    Galindo, Maria Mercedes; Rodriguez, Evelyn; Rojas, Maria Gabriela; Figarella, Katherine; Campelo, Riward; Ramírez, Jose Luis

    2009-07-01

    Here we studied the telomerase activity of the human parasite Leishmania major. In this organism we have detected a high activity of this enzyme once several parameters such as heat activation, sequence of extension primer, and protein concentration are adjusted. The activity was not only heat activated, but also very resistant to heat denaturation. We believe L. major telomerase is an important activity and it may provide an adequate drug therapy target. PMID:19426669

  19. Active solar heating and cooling information user study

    SciTech Connect

    Belew, W.W.; Wood, B.L.; Marle, T.L.; Reinhardt, C.L.

    1981-01-01

    The results of a series of telephone interviews with groups of users of information on active solar heating and cooling (SHAC). An earlier study identified the information user groups in the solar community and the priority (to accelerate solar energy commercialization) of getting information to each group. In the current study only high-priority groups were examined. Results from 19 SHAC groups respondents are analyzed in this report: DOE-Funded Researchers, Non-DOE-Funded Researchers, Representatives of Manufacturers (4 groups), Distributors, Installers, Architects, Builders, Planners, Engineers (2 groups), Representatives of Utilities, Educators, Cooperative Extension Service County Agents, Building Owners/Managers, and Homeowners (2 groups). The data will be used as input to the determination of information products and services the Solar Energy Research Institute, the Solar Energy Information Data Bank Network, and the entire information outreach community should be preparing and disseminating.

  20. Quality assessment of palm products upon prolonged heat treatment.

    PubMed

    Tarmizi, Azmil Haizam Ahmad; Lin, Siew Wai

    2008-01-01

    Extending the frying-life of oils is of commercial and economic importance. Due to this fact, assessment on the thermal stability of frying oils could provide considerable savings to the food processors. In this study, the physico-chemical properties of five palm products mainly palm oil, single-fractionated palm olein, double-fractionated palm olein, red palm olein and palm-based shortening during 80 hours of heating at 180 degrees C were investigated. Heating properties of these products were then compared with that of high oleic sunflower oil, which was used as reference oil. The indices applied in evaluating the quality changes of oils were free fatty acid, smoke point, p-anisidine value, tocols, polar and polymer compounds. Three palm products i.e. palm oil, single-fractionated palm olein and double-fractionated palm olein were identified to be the most stable in terms of lower formation of free fatty acid, polar and polymer compounds as well as preserving higher smoke point and tocols content compared to the other three oils. The low intensity of hydrolytic and oxidative changes due to prolonged heating, suggests that these palm products are inherently suitable for frying purposes.

  1. Changes of anthocyanins, anthocyanidins, and antioxidant activity in bilberry extract during dry heating.

    PubMed

    Yue, X; Xu, Z

    2008-08-01

    Thermal stability of 10 anthocyanins found in a bilberry extract was studied at different heating temperatures and times. Degradation of the 10 anthocyanins, delphinidin, cyanidin, petunidin, peonidin, and malvidin derivat with different conjugated sugars, followed 1st-order reaction kinetics at heating temperatures 80, 100, and 125 degrees C. Though the degradation rate constants of anthocyanins were not significantly different from each other at the same heating temperature, they increased drastically when heating temperature was increased to 125 degrees C. At that temperature, the half-lives for all anthocyanins were less than 8 min. The degradation rate constants followed the Arrhenius equation. The trend of lower activation energy of the anthocyanins with arabinoside than with galactoside or glucoside was observed. These conjugated sugars were cleaved from the anthocyanins to produce their corresponding anthocyanidins or aglycones during heating. The production of anthocyanidins increased con stantly and was converted from approximately 30% of the degraded anthocyanins when heated at 100 degrees C for up to 30 min. At 125 degrees C, the increase of anthocyanidins lasted for 10 min, after which the degradation rate of anthocyanidins exceeded the production rate. Antioxidant activities of the heated extracts were estimated by measuring DPPH (2, 2'-diphenyl-1-picrylhydrazyl) free radical scavenging activity. The extracts heated at 80 degrees C for 30 min, 100 degrees C for 10 and 20 min, and 125 degrees C for 10 min had higher free radical scavenging capability than unheated extract.

  2. Calcium promotes activity and confers heat stability on plant peroxidases

    PubMed Central

    Plieth, Christoph; Vollbehr, Sonja

    2012-01-01

    In this paper we demonstrate how peroxidase (PO) activities and their heat stability correlate with the availability of free Ca2+ ions. Calcium ions work as a molecular switch for PO activity and exert a protective function, rendering POs heat stable. The concentration ranges of these two activities differ markedly. POs are activated by µM Ca2+ concentration ranges, whereas heat stabilization is observed in the nM range. This suggests the existence of different Ca2+ binding sites. The heat stability of POs depends on the source plant species. Terrestrial plants have POs that exhibit higher temperature stability than those POs from limnic and marine plants. Different POs from a single species can differ in terms of heat stability. The abundance of different POs within a plant is dependent on age and developmental stage. The heat stability of a PO does not necessarily correlate with the maximum temperature the source species is usually exposed to in its natural habitat. This raises questions on the role of POs in the heat tolerance of plants. Consequently, detailed investigations are needed to identify and characterize individual POs, with regard to their genetic origin, subcellular expression, tissue abundance, developmental emergence and their functions in innate and acquired heat tolerance. PMID:22580695

  3. Activation of kinase phosphorylation by heat-shift and mild heat-shock

    PubMed Central

    Petrocchi, Pamela; Quaresima, Stefania; Patrizia Mongiardi, Maria; Severini, Cinzia; Possenti, Roberta

    2010-01-01

    Most cells activate intracellular signalling to recover from heat damage. An increase of temperature, known as HS (heat shock), induces two major signalling events: the transcriptional induction of HSPs (heat-shock proteins) and the activation of the MAPK (mitogen-activated protein kinase) cascade. We performed the present study to examine the effects of HS, induced by different experimental conditions, on various kinases [ERK (extracellular-signal-regulated kinase), JNK (c-Jun N-terminal kinase), p38, Akt, AMPK (AMP-activated protein kinase) and PKC (protein kinase C)]. We investigated by Western blot analysis the phosphorylation of MAPK as a measure of cellular responsiveness to heat shift (37°C) and mild HS (40°C) in different cell lines. The results of the study indicate that every cell line responded to heat shift, and to a greater extent to HS, increasing ERK and JNK phosphorylation, whereas variable effects on activation or inhibition of PKC, AMPK, Akt and p38 were observed. Besides the implications of intracellular signalling activated by heat variations, these data may be of technical relevance, indicating possible sources of error due to different experimental temperature conditions. PMID:23119140

  4. Activation of kinase phosphorylation by heat-shift and mild heat-shock.

    PubMed

    Petrocchi, Pamela; Quaresima, Stefania; Mongiardi, Maria Patrizia; Severini, Cinzia; Possenti, Roberta

    2010-01-01

    Most cells activate intracellular signalling to recover from heat damage. An increase of temperature, known as HS (heat shock), induces two major signalling events: the transcriptional induction of HSPs (heat-shock proteins) and the activation of the MAPK (mitogen-activated protein kinase) cascade. We performed the present study to examine the effects of HS, induced by different experimental conditions, on various kinases [ERK (extracellular-signal-regulated kinase), JNK (c-Jun N-terminal kinase), p38, Akt, AMPK (AMP-activated protein kinase) and PKC (protein kinase C)]. We investigated by Western blot analysis the phosphorylation of MAPK as a measure of cellular responsiveness to heat shift (37°C) and mild HS (40°C) in different cell lines. The results of the study indicate that every cell line responded to heat shift, and to a greater extent to HS, increasing ERK and JNK phosphorylation, whereas variable effects on activation or inhibition of PKC, AMPK, Akt and p38 were observed. Besides the implications of intracellular signalling activated by heat variations, these data may be of technical relevance, indicating possible sources of error due to different experimental temperature conditions.

  5. A New Model for Heat Flow in Extensional Basins: Estimating Radiogenic Heat Production

    SciTech Connect

    Waples, Douglas W.

    2002-06-15

    Radiogenic heat production (RHP) represents a significant fraction of surface heat flow, both on cratons and in sedimentary basins. RHP within continental crust-especially the upper crust-is high. RHP at any depth within the crust can be estimated as a function of crustal age. Mantle RHP, in contrast, is always low, contributing at most 1 to 2 mW/m{sup 2} to total heat flow. Radiogenic heat from any noncrystalline basement that may be present also contributes to total heat flow. RHP from metamorphic rocks is similar to or slightly lower than that from their precursor sedimentary rocks. When extension of the lithosphere occurs-as for example during rifting-the radiogenic contribution of each layer of the lithosphere and noncrystalline basement diminishes in direct proportion to the degree of extension of that layer. Lithospheric RHP today is somewhat less than in the distant past, as a result of radioactive decay. In modeling, RHP can be varied through time by considering the half lives of uranium, thorium, and potassium, and the proportional contribution of each of those elements to total RHP from basement. RHP from sedimentary rocks ranges from low for most evaporites to high for some shales, especially those rich in organic matter. The contribution to total heat flow of radiogenic heat from sediments depends strongly on total sediment thickness, and thus differs through time as subsidence and basin filling occur. RHP can be high for thick clastic sections. RHP in sediments can be calculated using ordinary or spectral gamma-ray logs, or it can be estimated from the lithology.

  6. Geothermal Energy Production With Innovative Methods Of Geothermal Heat Recovery

    SciTech Connect

    Swenson, Allen; Darlow, Rick; Sanchez, Angel; Pierce, Michael; Sellers, Blake

    2014-12-19

    The ThermalDrive™ Power System (“TDPS”) offers one of the most exciting technological advances in the geothermal power generation industry in the last 30 years. Using innovations in subsurface heat recovery methods, revolutionary advances in downhole pumping technology and a distributed approach to surface power production, GeoTek Energy, LLC’s TDPS offers an opportunity to change the geothermal power industry dynamics.

  7. Heat of Hydration of Low Activity Cementitious Waste Forms

    SciTech Connect

    Nasol, D.

    2015-07-23

    During the curing of secondary waste grout, the hydraulic materials in the dry mix react exothermally with the water in the secondary low-activity waste (LAW). The heat released, called the heat of hydration, can be measured using a TAM Air Isothermal Calorimeter. By holding temperature constant in the instrument, the heat of hydration during the curing process can be determined. This will provide information that can be used in the design of a waste solidification facility. At the Savannah River National Laboratory (SRNL), the heat of hydration and other physical properties are being collected on grout prepared using three simulants of liquid secondary waste generated at the Hanford Site. From this study it was found that both the simulant and dry mix each had an effect on the heat of hydration. It was also concluded that the higher the cement content in the dry materials mix, the greater the heat of hydration during the curing of grout.

  8. Oxidative Activity of Heated Coal Affected by Antypirogens

    NASA Astrophysics Data System (ADS)

    Torosyan, V. F.; Torosyan, E. S.; Borovikov, I. F.; Yakutova, V. A.

    2016-04-01

    The effect of antypirogens on chemical activity of heated coal is studied. It is proved that ammonium sulfate, calcium phosphate, calcium chloride, calcium nitrate and acid fluoride are the most effective antypirogens.

  9. Balloons and Bottles: Activities on Air-Sea Heat Exchange.

    ERIC Educational Resources Information Center

    Murphree, Tom

    1998-01-01

    Presents an activity designed to demonstrate how heating and cooling an air mass affects its temperature, volume, density, and pressure. Illustrates how thermal energy can cause atmospheric motion such as expansion, contraction, and winds. (Author/WRM)

  10. Constant Temperature Storage House Heated by the Respiration Heat of Agricultural Products

    NASA Astrophysics Data System (ADS)

    Kobiyama, Masayoshi; Takegata, Kiyohide; Hashimoto, Yoshiaki; Kawamoto, Syuroh; Ohno, Syozi

    HIMURO type storage house, cooled by natural snow/ice, has been practically applied by means of its good storing condition and of the easy handling. As this type storage house is constructed by enough insulation structure, it can been used not only for a cool house in the summer but also a constant temperature storage house in the winter. In this paper, the authors suggested that the HIMURO type storage house might be used as the constant temperature house in the severe cold winter season after the theoretical investigation on the thermal characteristics of it. In general, the conventional type constant temperature storage house is heated by heater throughout storing period, that of this paper is self heated by the respiration heat of agricultural products stored in this house, so the house proposed in this paper look forward to smaller heat addition than that of conventional house. The practical experiment was performed to verify the theoretical investigation and to observe the storing condition of the product and we obtained enough results.

  11. Active latent heat storage with a screw heat exchanger - experimental results for heat transfer and concept for high pressure steam

    NASA Astrophysics Data System (ADS)

    Zipf, Verena; Willert, Daniel; Neuhäuser, Anton

    2016-05-01

    An innovative active latent heat storage concept was invented and developed at Fraunhofer ISE. It uses a screw heat exchanger (SHE) for the phase change during the transport of a phase change material (PCM) from a cold to a hot tank or vice versa. This separates heat transfer and storage tank in comparison to existing concepts. A test rig has been built in order to investigate the heat transfer coefficients of the SHE during melting and crystallization of the PCM. The knowledge of these characteristics is crucial in order to assess the performance of the latent heat storage in a thermal system. The test rig contains a double shafted SHE, which is heated or cooled with thermal oil. The overall heat transfer coefficient U and the convective heat transfer coefficient on the PCM side hPCM both for charging and discharging have been calculated based on the measured data. For charging, the overall heat transfer coefficient in the tested SHE was Uch = 308 W/m2K and for discharging Udis = 210 W/m2K. Based on the values for hPCM the overall heat transfer coefficients for a larger SHE with steam as heat transfer fluid and an optimized geometry were calculated with Uch = 320 W/m2K for charging and Udis = 243 W/m2K for discharging. For pressures as high as p = 100 bar, an SHE concept has been developed, which uses an organic fluid inside the flight of the SHE as working media. With this concept, the SHE can also be deployed for very high pressure, e.g. as storage in solar thermal power plants.

  12. Transcriptional activation of heat-shock genes in eukaryotes.

    PubMed

    Tanguay, R M

    1988-06-01

    Prokaryotes and eukaryotes respond to thermal or various chemical stresses by the rapid induction of a group of genes collectively referred to as the heat shock genes. In eucaryotes, the expression of these genes is primarily regulated at the transcriptional level. The early observations that transfected heat shock genes were inducible in heterologous systems suggested the existence of common regulatory elements in these ubiquitous genes. Sequence analysis of cloned Drosophila heat shock genes revealed a conserved 14 base pair (bp) inverted repeat, which is essential for heat induction. This regulatory sequence, referred to as the heat shock element (HSE), is found in multiple imperfect copies upstream of the TATA box of all heat shock genes. While studies in heterologous systems indicated that a single copy of HSE was sufficient for inducibility, further analysis in homologous assays suggests that multiple HSE can act in a cooperative way and that the efficiency of transcriptional activation is related, within limits, to the number of HSE. Comparative analysis of heat shock genes reveals that HSE can be positioned at different distances from the TATA box in either orientation, a behavior reminiscent of enhancer elements. However, the presence of HSE does not necessarily confer heat inducibility, as shown by their presence in the constitutively expressed but non-heat-inducible homologous cognate genes. Footprinting and nuclease mapping have been used to show that a protein factor (HSTF: heat shock transcription factor) binds to the HSE element, activating heat shock gene transcription in a dose-dependent manner. The recent progress in the isolation and characterization of HSTF in Drosophila, yeast, and human cells is reviewed. Finally, different models suggested to account for the positive regulation of heat shock genes by the HSTF are presented.

  13. Active heat exchange system development for latent heat thermal energy storage

    NASA Technical Reports Server (NTRS)

    Lefrois, R. T.; Knowles, G. R.; Mathur, A. K.; Budimir, J.

    1979-01-01

    Active heat exchange concepts for use with thermal energy storage systems in the temperature range of 250 C to 350 C, using the heat of fusion of molten salts for storing thermal energy are described. Salt mixtures that freeze and melt in appropriate ranges are identified and are evaluated for physico-chemical, economic, corrosive and safety characteristics. Eight active heat exchange concepts for heat transfer during solidification are conceived and conceptually designed for use with selected storage media. The concepts are analyzed for their scalability, maintenance, safety, technological development and costs. A model for estimating and scaling storage system costs is developed and is used for economic evaluation of salt mixtures and heat exchange concepts for a large scale application. The importance of comparing salts and heat exchange concepts on a total system cost basis, rather than the component cost basis alone, is pointed out. The heat exchange concepts were sized and compared for 6.5 MPa/281 C steam conditions and a 1000 MW(t) heat rate for six hours. A cost sensitivity analysis for other design conditions is also carried out.

  14. Direct activation of platelets by heat is the possible trigger of the coagulopathy of heat stroke.

    PubMed

    Gader, A M; al-Mashhadani, S A; al-Harthy, S S

    1990-01-01

    The trigger of the coagulopathy that complicates heat stroke is obscure, but direct platelet activation by heat is a possibility we set out to study. Platelet rich plasma (PRP), prepared from blood donors, was incubated at increasing temperatures (38-45 degrees C) and then platelet aggregation was undertaken in response to decreasing low doses of ADP (less than 2.0 mumol/l). Hyperaggregability was manifested when the incubation temperature reached 43 degrees C and was maximum at 44 degrees C before complete inhibition of responses at 45 degrees C. The platelet hyperactivity induced by heating at 44 degrees C persisted after reincubating PRP samples at 37 degrees C. These platelet responses could not be triggered in PRP samples prepared from subjects after the overnight ingestion of aspirin or after the addition of aspirin to PRP before starting the heating procedure. However, aspirin was less effective when added to PRP after the appearance of the heat-induced hyperaggregability. In conclusion, these results indicate that platelets can be activated directly by heat. This mechanism which may be operational in heat stroke, is unaffected by cooling (body cooling being basic in the management of heat stroke) but can be prevented by the early administration of aspirin. PMID:2310701

  15. Observing single enzyme molecules interconvert between activity states upon heating.

    PubMed

    Rojek, Marcin J; Walt, David R

    2014-01-01

    In this paper, we demonstrate that single enzyme molecules of β-galactosidase interconvert between different activity states upon exposure to short pulses of heat. We show that these changes in activity are the result of different enzyme conformations. Hundreds of single β-galactosidase molecules are trapped in femtoliter reaction chambers and the individual enzymes are subjected to short heating pulses. When heating pulses are introduced into the system, the enzyme molecules switch between different activity states. Furthermore, we observe that the changes in activity are random and do not correlate with the enzyme's original activity. This study demonstrates that different stable conformations play an important role in the static heterogeneity reported previously, resulting in distinct long-lived activity states of enzyme molecules in a population.

  16. Crowding Activates Heat Shock Protein 90.

    PubMed

    Halpin, Jackson C; Huang, Bin; Sun, Ming; Street, Timothy O

    2016-03-18

    Hsp90 is a dimeric ATP-dependent chaperone involved in the folding, maturation, and activation of diverse target proteins. Extensive in vitro structural analysis has led to a working model of Hsp90's ATP-driven conformational cycle. An implicit assumption is that dilute experimental conditions do not significantly perturb Hsp90 structure and function. However, Hsp90 undergoes a dramatic open/closed conformational change, which raises the possibility that this assumption may not be valid for this chaperone. Indeed, here we show that the ATPase activity of Hsp90 is highly sensitive to molecular crowding, whereas the ATPase activities of Hsp60 and Hsp70 chaperones are insensitive to crowding conditions. Polymer crowders activate Hsp90 in a non-saturable manner, with increasing efficacy at increasing concentration. Crowders exhibit a non-linear relationship between their radius of gyration and the extent to which they activate Hsp90. This experimental relationship can be qualitatively recapitulated with simple structure-based volume calculations comparing open/closed configurations of Hsp90. Thermodynamic analysis indicates that crowding activation of Hsp90 is entropically driven, which is consistent with a model in which excluded volume provides a driving force that favors the closed active state of Hsp90. Multiple Hsp90 homologs are activated by crowders, with the endoplasmic reticulum-specific Hsp90, Grp94, exhibiting the highest sensitivity. Finally, we find that crowding activation works by a different mechanism than co-chaperone activation and that these mechanisms are independent. We hypothesize that Hsp90 has a higher intrinsic activity in the cell than in vitro. PMID:26797120

  17. Heat storage in Asian elephants during submaximal exercise: behavioral regulation of thermoregulatory constraints on activity in endothermic gigantotherms.

    PubMed

    Rowe, M F; Bakken, G S; Ratliff, J J; Langman, V A

    2013-05-15

    Gigantic size presents both opportunities and challenges in thermoregulation. Allometric scaling relationships suggest that gigantic animals have difficulty dissipating metabolic heat. Large body size permits the maintenance of fairly constant core body temperatures in ectothermic animals by means of gigantothermy. Conversely, gigantothermy combined with endothermic metabolic rate and activity likely results in heat production rates that exceed heat loss rates. In tropical environments, it has been suggested that a substantial rate of heat storage might result in a potentially lethal rise in core body temperature in both elephants and endothermic dinosaurs. However, the behavioral choice of nocturnal activity might reduce heat storage. We sought to test the hypothesis that there is a functionally significant relationship between heat storage and locomotion in Asian elephants (Elephas maximus), and model the thermoregulatory constraints on activity in elephants and a similarly sized migratory dinosaur, Edmontosaurus. Pre- and post-exercise (N=37 trials) measurements of core body temperature and skin temperature, using thermography were made in two adult female Asian elephants at the Audubon Zoo in New Orleans, LA, USA. Over ambient air temperatures ranging from 8 to 34.5°C, when elephants exercised in full sun, ~56 to 100% of active metabolic heat production was stored in core body tissues. We estimate that during nocturnal activity, in the absence of solar radiation, between 5 and 64% of metabolic heat production would be stored in core tissues. Potentially lethal rates of heat storage in active elephants and Edmontosaurus could be behaviorally regulated by nocturnal activity.

  18. Heat storage in Asian elephants during submaximal exercise: behavioral regulation of thermoregulatory constraints on activity in endothermic gigantotherms.

    PubMed

    Rowe, M F; Bakken, G S; Ratliff, J J; Langman, V A

    2013-05-15

    Gigantic size presents both opportunities and challenges in thermoregulation. Allometric scaling relationships suggest that gigantic animals have difficulty dissipating metabolic heat. Large body size permits the maintenance of fairly constant core body temperatures in ectothermic animals by means of gigantothermy. Conversely, gigantothermy combined with endothermic metabolic rate and activity likely results in heat production rates that exceed heat loss rates. In tropical environments, it has been suggested that a substantial rate of heat storage might result in a potentially lethal rise in core body temperature in both elephants and endothermic dinosaurs. However, the behavioral choice of nocturnal activity might reduce heat storage. We sought to test the hypothesis that there is a functionally significant relationship between heat storage and locomotion in Asian elephants (Elephas maximus), and model the thermoregulatory constraints on activity in elephants and a similarly sized migratory dinosaur, Edmontosaurus. Pre- and post-exercise (N=37 trials) measurements of core body temperature and skin temperature, using thermography were made in two adult female Asian elephants at the Audubon Zoo in New Orleans, LA, USA. Over ambient air temperatures ranging from 8 to 34.5°C, when elephants exercised in full sun, ~56 to 100% of active metabolic heat production was stored in core body tissues. We estimate that during nocturnal activity, in the absence of solar radiation, between 5 and 64% of metabolic heat production would be stored in core tissues. Potentially lethal rates of heat storage in active elephants and Edmontosaurus could be behaviorally regulated by nocturnal activity. PMID:23785105

  19. CME Productivity of Active Regions.

    NASA Astrophysics Data System (ADS)

    Liu, L.; Wang, Y.; Wang, J.; Shen, C.; Ye, P.; Zhang, Q.; Liu, R.; Wang, S.

    2015-12-01

    Solar active regions (ARs) are the major sources of two kinds of the most violent solar eruptions, namely flares and coronal mass ejections (CMEs). Although they are believed to be two phenomena in the same eruptive process, the productivity of them could be quiet different for various ARs. Why is an AR productive? And why is a flare-rich AR CME-poor? To answer these questions, we compared the recent super flare-rich but CME-poor AR 12192, with other four ARs; two were productive in both flares and CMEs and the other two were inert to produce any M-class or intenser flares or CMEs. By investigating the photospheric parameters based on the SDO/HMI vector magnetogram, we find the three productive ARs have larger magnetic flux, current and free magnetic energy than the inert ARs. Furthermore, the two ARs productive in both flares and CMEs contain higher current helicity, concentrating along both sides of the flaring neutral lines, indicating the presence of a seed magnetic structure( that is highly sheared or twisted) of a CME; they also have higher decay index in the low corona, showing weak constraint. The results suggest that productive ARs are always large and have strong current system and sufficient free energy to power flares, and more importantly whether or not a flare is accompanied by a CME is seemingly related to (1) if there is significant sheared or twisted core field serving as the seed of the CME and (2) if the constraint of the overlying arcades is weak enough. Moreover, some productive ARs may frequently produce more than one CME. How does this happen? We do a statistical investigation of waiting times of quasi-homologous CMEs ( CME ssuccessive originating from the same ARs within short intervals) from super ARs in solar cycle 23 to answer this question. The waiting times of quasi-homologous CMEs have a two-component distribution with a separation at about 18 hours, the first component peaks at 7 hours. The correlation analysis among CME waiting times

  20. Solar production of intermediate temperature process heat, phase 1 design

    NASA Astrophysics Data System (ADS)

    1980-08-01

    The system consists of 42,420 sq ft of parabolic trough, single axis tracking, concentrating solar collectors. The collectors are oriented in a North-South configuration and track East-West. A heat transfer fluid (Gulf Synfluid 4cs) is circulated in a closed loop fashion through the solar collectors and a series of heat exchangers. The inlet and outlet fluid temperatures for the collectors are 370 F and 450 F respectively. These temperatures are constantly maintained via a variable flow rate through the collectors (the flow rate varies in direct proportion to the level of insolation). Superheated steam is the final product of the solar energy system. Final steam quality at the steam generator is 420 F and 165 Psia.

  1. Hydrogen production from coal using a nuclear heat source

    NASA Technical Reports Server (NTRS)

    Quade, R. N.

    1976-01-01

    A strong candidate for hydrogen production in the intermediate time frame of 1985 to 1995 is a coal-based process using a high-temperature gas-cooled reactor (HTGR) as a heat source. Expected process efficiencies in the range of 60 to 70% are considerably higher than all other hydrogen production processes except steam reforming of a natural gas. The process involves the preparation of a coal liquid, hydrogasification of that liquid, and steam reforming of the resulting gaseous or light liquid product. A study showing process efficiency and cost of hydrogen vs nuclear reactor core outlet temperature has been completed, and shows diminishing returns at process temperatures above about 1500 F. A possible scenario combining the relatively abundant and low-cost Western coal deposits with the Gulf Coast hydrogen users is presented which provides high-energy density transportation utilizing coal liquids and uranium.

  2. Molecular responses of Escherichia coli caused by heat stress and recombinant protein production during temperature induction.

    PubMed

    Valdez-Cruz, Norma A; Ramírez, Octavio T; Trujillo-Roldán, Mauricio A

    2011-01-01

    In a recent review, we discussed the extensively used temperature-inducible expression system, based on the pL and/or pR phage lambda promoters that are finely regulated by the thermo-labile cI857 repressor. In this system, an increase in temperature induces the heterologous protein production and activates the heat shock response, as well as the stringent and SOS responses. The same responses are activated just by the overproduction of recombinant protein. All such responses result in a metabolic burden to the cells, a decrease in the specific growth rate, and alterations in the central carbon metabolism. Altogether, these effects can alter the quantity and quality of the produced foreign protein. Here, we compare and discuss the transcription of selected genes, and the concomitant synthesis of heat-shock proteins (hsp) soon after thermal induction, in relation to the responses that occur in other expression systems that also trigger the heat-shock response.

  3. Active heat exchange system development for latent heat thermal energy storage

    NASA Astrophysics Data System (ADS)

    Lefrois, R. T.; Mathur, A. K.

    1980-04-01

    Five tasks to select, design, fabricate, test and evaluate candidate active heat exchanger modules for future applications to solar and conventional utility power plants were discussed. Alternative mechanizations of active heat exchange concepts were analyzed for use with heat of fusion phase change materials (PCMs) in the temperature range of 250 to 350 C. Twenty-six heat exchange concepts were reviewed, and eight were selected for detailed assessment. Two candidates were selected for small-scale experimentation: a coated tube and shell heat exchanger and a direct contact reflux boiler. A dilute eutectic mixture of sodium nitrate and sodium hydroxide was selected as the PCM from over 50 candidate inorganic salt mixtures. Based on a salt screening process, eight major component salts were selected initially for further evaluation. The most attractive major components in the temperature range of 250 to 350 C appeared to be NaNO3, NaNO2, and NaOH. Sketches of the two active heat exchange concepts selected for test are given.

  4. Active heat exchange system development for latent heat thermal energy storage

    NASA Technical Reports Server (NTRS)

    Lefrois, R. T.; Mathur, A. K.

    1980-01-01

    Five tasks to select, design, fabricate, test and evaluate candidate active heat exchanger modules for future applications to solar and conventional utility power plants were discussed. Alternative mechanizations of active heat exchange concepts were analyzed for use with heat of fusion phase change materials (PCMs) in the temperature range of 250 to 350 C. Twenty-six heat exchange concepts were reviewed, and eight were selected for detailed assessment. Two candidates were selected for small-scale experimentation: a coated tube and shell heat exchanger and a direct contact reflux boiler. A dilute eutectic mixture of sodium nitrate and sodium hydroxide was selected as the PCM from over 50 candidate inorganic salt mixtures. Based on a salt screening process, eight major component salts were selected initially for further evaluation. The most attractive major components in the temperature range of 250 to 350 C appeared to be NaNO3, NaNO2, and NaOH. Sketches of the two active heat exchange concepts selected for test are given.

  5. Stellar activity and coronal heating: an overview of recent results.

    PubMed

    Testa, Paola; Saar, Steven H; Drake, Jeremy J

    2015-05-28

    Observations of the coronae of the Sun and of solar-like stars provide complementary information to advance our understanding of stellar magnetic activity, and of the processes leading to the heating of their outer atmospheres. While solar observations allow us to study the corona at high spatial and temporal resolution, the study of stellar coronae allows us to probe stellar activity over a wide range of ages and stellar parameters. Stellar studies therefore provide us with additional tools for understanding coronal heating processes, as well as the long-term evolution of solar X-ray activity. We discuss how recent studies of stellar magnetic fields and coronae contribute to our understanding of the phenomenon of activity and coronal heating in late-type stars. PMID:25897087

  6. Stellar activity and coronal heating: an overview of recent results

    PubMed Central

    Testa, Paola; Saar, Steven H.; Drake, Jeremy J.

    2015-01-01

    Observations of the coronae of the Sun and of solar-like stars provide complementary information to advance our understanding of stellar magnetic activity, and of the processes leading to the heating of their outer atmospheres. While solar observations allow us to study the corona at high spatial and temporal resolution, the study of stellar coronae allows us to probe stellar activity over a wide range of ages and stellar parameters. Stellar studies therefore provide us with additional tools for understanding coronal heating processes, as well as the long-term evolution of solar X-ray activity. We discuss how recent studies of stellar magnetic fields and coronae contribute to our understanding of the phenomenon of activity and coronal heating in late-type stars. PMID:25897087

  7. Stellar activity and coronal heating: an overview of recent results.

    PubMed

    Testa, Paola; Saar, Steven H; Drake, Jeremy J

    2015-05-28

    Observations of the coronae of the Sun and of solar-like stars provide complementary information to advance our understanding of stellar magnetic activity, and of the processes leading to the heating of their outer atmospheres. While solar observations allow us to study the corona at high spatial and temporal resolution, the study of stellar coronae allows us to probe stellar activity over a wide range of ages and stellar parameters. Stellar studies therefore provide us with additional tools for understanding coronal heating processes, as well as the long-term evolution of solar X-ray activity. We discuss how recent studies of stellar magnetic fields and coronae contribute to our understanding of the phenomenon of activity and coronal heating in late-type stars.

  8. Activated-Carbon Sorbent With Integral Heat-Transfer Device

    NASA Technical Reports Server (NTRS)

    Jones, Jack A.; Yavrouian, Andre

    1996-01-01

    Prototype adsorption device used, for example, in adsorption heat pump, to store natural gas to power automobile, or to separate components of fluid mixtures. Device includes activated carbon held together by binder and molded into finned heat-transfer device providing rapid heating or cooling to enable rapid adsorption or desorption of fluids. Concepts of design and fabrication of device equally valid for such other highly thermally conductive devices as copper-finned tubes, and for such other high-surface-area sorbents as zeolites or silicates.

  9. Heat Resistance of Salmonella in Various Egg Products

    PubMed Central

    Garibaldi, J. A.; Straka, R. P.; Ijichi, K.

    1969-01-01

    The heat-resistance characteristics of Salmonella typhimurium Tm-1, a reference strain in the stationary phase of growth, were determined at several temperatures in the major types of products produced by the egg industry. The time required to kill 90% of the population (D value) at a given temperature in specific egg products was as follows: at 60 C (140 F), D = 0.27 min for whole egg; D = 0.60 min for whole egg plus 10% sucrose; D = 1.0 min for fortified whole egg; D = 0.20 min for egg white (pH 7.3), stabilized with aluminum; D = 0.40 min for egg yolk; D = 4.0 min for egg yolk plus 10% sucrose; D = 5.1 min for egg yolk plus 10% NaCl; D = 1.0 min for scrambled egg mix; at 55 C (131 F), D = 0.55 min for egg white (pH 9.2); D = 1.2 min for egg white (pH 9.2) plus 10% sucrose. The average Z value (number of degrees, either centigrade or fahrenheit, for a thermal destruction time curve to traverse one logarithmic cycle) was 4.6 C (8.3 F) with a range from 4.2 to 5.3 C. Supplementation with 10% sucrose appeared to have a severalfold greater effect on the heat stabilization of egg white proteins than on S. typhimurium Tm-1. This information should be of value in the formulation of heat treatments to insure that all egg products be free of viable salmonellae. Images PMID:4890741

  10. 77 FR 33486 - Certain Integrated Circuit Packages Provided With Multiple Heat-Conducting Paths and Products...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-06

    ... COMMISSION Certain Integrated Circuit Packages Provided With Multiple Heat- Conducting Paths and Products... With Multiple Heat-Conducting Paths and Products Containing Same, DN 2899; the Commission is soliciting... multiple heat-conducting paths and products containing same. The complaint names as respondents...

  11. Laser production and heating of plasma for MHD application

    NASA Technical Reports Server (NTRS)

    Jalufka, N. W.

    1988-01-01

    Experiments have been made on the production and heating of plasmas by the absorption of laser radiation. These experiments were performed to ascertain the feasibility of using laser-produced or laser-heated plasmas as the input for a magnetohydrodynamic (MHD) generator. Such a system would have a broad application as a laser-to-electricity energy converter for space power transmission. Experiments with a 100-J-pulsed CO2 laser were conducted to investigate the breakdown of argon gas by a high-intensity laser beam, the parameters (electron density and temperature) of the plasma produced, and the formation and propagation of laser-supported detonation (LSD) waves. Experiments were also carried out using a 1-J-pulsed CO2 laser to heat the plasma produced in a shock tube. The shock-tube hydrogen plasma reached electron densities of approximately 10 to the 17th/cu cm and electron temperatures of approximately 1 eV. Absorption of the CO2 laser beam by the plasma was measured, and up to approximately 100 percent absorption was observed. Measurements with a small MHD generator showed that the energy extraction efficiency could be very large with values up to 56 percent being measured.

  12. Heat exposure, cardiovascular stress and work productivity in rice harvesters in India: implications for a climate change future.

    PubMed

    Sahu, Subhashis; Sett, Moumita; Kjellstrom, Tord

    2013-01-01

    Excessive workplace heat exposures create well-known risks of heat stroke, and it limits the workers' capacity to sustain physical activity. There is very limited evidence available on how these effects reduce work productivity, while the quantitative relationship between heat and work productivity is an essential basis for climate change impact assessments. We measured hourly heat exposure in rice fields in West Bengal and recorded perceived health problems via interviews of 124 rice harvesters. In a sub-group (n = 48) heart rate was recorded every minute in a standard work situation. Work productivity was recorded as hourly rice bundle collection output. The hourly heat levels (WBGT = Wet Bulb Globe Temperature) were 26-32°C (at air temperatures of 30-38°C), exceeding international standards. Most workers reported exhaustion and pain during work on hot days. Heart rate recovered quickly at low heat, but more slowly at high heat, indicating cardiovascular strain. The hourly number of rice bundles collected was significantly reduced at WBGT>26°C (approximately 5% per°C of increased WBGT). We conclude that high heat exposure in agriculture caused heat strain and reduced work productivity. This reduction will be exacerbated by climate change and may undermine the local economy.

  13. Optical investigation of heat release and NOx production in combustion

    NASA Astrophysics Data System (ADS)

    Timmerman, B. H.; Bryanston-Cross, P. J.

    2007-10-01

    Two novel optical techniques are presented for non-intrusive, spatially resolved study of combustion, both based on passive Optical Emission Tomography (OET). Firstly, OET is used for non-intrusive study of heat release through the detection of chemiluminescence by the hydroxyl radical that is generated in the burning process. The OET technique presented here is based on a passive fibre-optic detection system, which allows spatially resolved high-frequency detection of the flame front in a combustion flame, where all fibres detect the emission signals simultaneously. The system withstands the high pressures and temperatures typically encountered in the harsh environments of gas turbine combustors and IC engines. The sensor-array is non-intrusive, low-cost, compact, simple to configure and can be quickly set up around a combustion field. The maximum acquisition rate is 2 kHz. This allows spatially resolved study of the fast phenomena in combustion. Furthermore, a method is presented for study of the production of NOx through chemiluminescence from tri-methyl-borate (TMB). In combustion, the tri-methyl-borate produces green luminescence in locations where NOx would be produced. Combining the green luminescence visualisation with UV detection of the hydroxyl radical allows monitoring of heat release and of NOx production areas, thus giving a means of studying both the burning process and the resulting NOx pollution.

  14. Optical investigation of heat release and NOx production in combustion

    NASA Astrophysics Data System (ADS)

    Timmerman, B. H.; Patel, S.; Dunkley, P.; Bryanston-Cross, P. J.

    2005-08-01

    Two passive optical techniques are described to investigate combustion. Optical Emission Tomography (OET) is used for non-intrusive study of heat release through the detection of chemiluminescence by the hydroxyl radical that is generated in the burning process. The OET technique described here is based on a passive fibre-optic detection system, which allows spatially resolved high-frequency detection of the flame front in a combustion flame, where all fibres detect the emission signals simultaneously. The system withstands the high pressures and temperatures typically encountered in the harsh environments of gas turbine combustors and IC engines. The sensor-array is non-intrusive, low-cost, compact, simple to configure and can be quickly set up around a combustion field. The maximum acquisition rate is 2 kHz. This allows spatially resolved study of the fast phenomena in combustion. Furthermore, the production of NOx is investigated through the emission of green light as a result of adding tri-methyl-borate to a flame. In combustion, the tri-methyl-borate produces green luminescence in locations where NOx would be produced. Combining the green luminescence visualisation with OET detection of the hydroxyl radical allows monitoring of heat release and of NOx production areas, thus giving a means of studying both the burning process and the resulting NOx pollution.

  15. Effects of heating rate on slow pyrolysis behavior, kinetic parameters and products properties of moso bamboo.

    PubMed

    Chen, Dengyu; Zhou, Jianbin; Zhang, Qisheng

    2014-10-01

    Effects of heating rate on slow pyrolysis behaviors, kinetic parameters, and products properties of moso bamboo were investigated in this study. Pyrolysis experiments were performed up to 700 °C at heating rates of 5, 10, 20, and 30 °C/min using thermogravimetric analysis (TGA) and a lab-scale fixed bed pyrolysis reactor. The results show that the onset and offset temperatures of the main devolatilization stage of thermogravimetry/derivative thermogravimetry (TG/DTG) curves obviously shift toward the high-temperature range, and the activation energy values increase with increasing heating rate. The heating rate has different effects on the pyrolysis products properties, including biochar (element content, proximate analysis, specific surface area, heating value), bio-oil (water content, chemical composition), and non-condensable gas. The solid yields from the fixed bed pyrolysis reactor are noticeably different from those of TGA mainly because the thermal hysteresis of the sample in the fixed bed pyrolysis reactor is more thorough.

  16. Modelling of labour productivity loss due to climate change: HEAT-SHIELD

    NASA Astrophysics Data System (ADS)

    Kjellstrom, Tord; Daanen, Hein

    2016-04-01

    Climate change will bring higher heat levels (temperature and humidity combined) to large parts of the world. When these levels reach above thresholds well defined by human physiology, the ability to maintain physical activity levels decrease and labour productivity is reduced. This impact is of particular importance in work situations in areas with long high intensity hot seasons, but also affects cooler areas during heat waves. Our modelling of labour productivity loss includes climate model data of the Inter-Sectoral Impact Model Inter-comparison Project (ISI-MIP), calculations of heat stress indexes during different months, estimations of work capacity loss and its annual impacts in different parts of the world. Different climate models will be compared for the Representative Concentration Pathways (RCPs) and the outcomes of the 2015 Paris Climate Conference (COP21) agreements. The validation includes comparisons of modelling outputs with actual field studies using historical heat data. These modelling approaches are a first stage contribution to the European Commission funded HEAT-SHIELD project.

  17. Dipeptidase activity and growth of heat-treated commercial dairy starter culture.

    PubMed

    Garbowska, Monika; Pluta, Antoni; Berthold-Pluta, Anna

    2015-03-01

    Growing expectations of consumers of fermented dairy products urge the search for novel solutions that would improve their organoleptic properties and in the case of rennet cheeses-that would also accelerate their ripening process. The aim of this study was to determine the peptidolytic activities and growth of heat-treated commercial culture of lactic acid bacteria. The analyzed culture was characterized by a relatively high peptidolytic activity. The growth of bacterial culture subjected to heat treatment at 50-80 °C for 15 s, 10 and 3 min was delayed by a few or 10-20 h compared to the control culture. Based on the results achieved, it may be concluded that in the production of rennet cheeses, the application of additional, fermentation-impaired starter cultures (via heating for ten or so minutes) may serve to accelerate their ripening and to improve their sensory attributes.

  18. Calorimetric study on human erythrocyte glycolysis. Heat production in various metabolic conditions.

    PubMed

    Minakami, S; de Verdier, C H

    1976-06-01

    The heat production of human erythrocytes was measured on a flow microcalorimeter with simultaneous analyses of lactate and other metabolites. The heat production connected with the lactate formation was about 17 kcal (71 kJ) per mol lactate formed which corresponded to the sum of heat production due to the formation of lactate from glucose and the heat production due to neutralization. The heat production rate increased as the pH of the suspension increased, corresponding to the increase in lactate formation. Glycolytic inhibitors such as fluoride and monoiodoacetate caused a decrease in the rate of heat production, whereas arsenate induced a large transient increase in heat production associated with a transient increase in lactate formation. Decrease in pyruvate concentration was usually associated with increase in heat production, although the decreased pyruvate concentration was coupled with formation of 2,3-bisphosphoglycerate. When inosine, dihydroxyacetone or D-glyceraldehyde was used as a substrate, an increase in the heat production rate was observed. Addition of methylene blue caused an oxygen uptake which was accompanied by a remarkable increase in heat production rate corresponding to about 160 kcal (670 kJ) per mol oxygen consumed. The value for heat production in red cells in the above-mentioned metabolic conditions was considered in relation to earlier known data on free energy and enthalpy changes of the different metabolic steps in the glycolytic pathway.

  19. Sympathetic activity during passive heat stress in healthy aged humans

    PubMed Central

    Gagnon, Daniel; Schlader, Zachary J; Crandall, Craig G

    2015-01-01

    Abstract Cardiovascular adjustments during heat stress are generally attenuated in healthy aged humans, which could be due to lower increases in sympathetic activity compared to the young. We compared muscle sympathetic nerve activity (MSNA) between 11 young (Y: 28 ± 4 years) and 10 aged (A: 70 ± 5 years) subjects prior to and during passive heating. Furthermore, MSNA responses were compared when a cold pressor test (CPT) and lower body negative pressure (LBNP) were superimposed upon heating. Baseline MSNA burst frequency (Y: 15 ± 4 vs. A: 31 ± 3 bursts min−1, P ≤ 0.01) and burst incidence (Y: 26 ± 8 vs. A: 50 ± 7 bursts (100 cardiac cycles (CC))−1, P ≤ 0.01) were greater in the aged. Heat stress increased core temperature to a similar extent in both groups (Y: +1.2 ± 0.1 vs. A: +1.2 ± 0.0°C, P = 0.99). Absolute levels of MSNA remained greater in the aged during heat stress (burst frequency: Y: 47 ± 6 vs. A: 63 ± 11 bursts min−1, P ≤ 0.01; burst incidence: Y: 48 ± 8 vs. A: 67 ± 9 bursts (100 CC)−1, P ≤ 0.01); however, the increase in both variables was similar between groups (both P ≥ 0.1). The CPT and LBNP further increased MSNA burst frequency and burst incidence, although the magnitude of increase was similar between groups (both P ≥ 0.07). These results suggest that increases in sympathetic activity during heat stress are not attenuated in healthy aged humans. Key points Cardiovascular adjustments to heat stress are attenuated in healthy aged individuals, which could contribute to their greater prevalence of heat-related illnesses and deaths during heat waves. The attenuated cardiovascular adjustments in the aged could be due to lower increases in sympathetic nerve activity during heat stress. We examined muscle sympathetic nerve activity (MSNA) and plasma catecholamine concentrations in healthy young and aged individuals during whole-body passive heat stress. The main finding

  20. Characterization of Heat Melt Compactor (HMC) Product Water

    NASA Technical Reports Server (NTRS)

    Harris, Linden; Wignarajah, Kanapathipi; Alba, Richard Gilbert; Pace, Gregory S.; Fisher, John W.

    2013-01-01

    The Heat Melt Compactor (HMC) is designed to sterilize and process wastes produced during space missions. Benefits of the HMC include reduction of biohazards to the crew, reduction in volume of wastes that would otherwise require storage, production of radiation shielding tiles, and recovery of water and other resources. Water reuse is critical onboard spacecrafts; it reduces the need for resupply missions and saves valuable storage space. The main sources of water in HMC batches are food, beverages, shampoo, disinfecting wipes, toothpaste, and diapers. Water reclaimed by the HMC was analyzed for concentrations of Na+, NH4+, K+, Mg2+, Ca2+, Cl-­-, NO2-­-, Br-­-, NO3-­-, PO43-­-, SO42-­-, total organic carbon (TOC), total inorganic carbon (TIC), % total solids, and pH. The data are discussed in relation to the current water input characteristics established for the International Space Station Water Processor Assembly system. Batches with higher than average amounts of food produced HMC product water with higher sulfate content, and batches with higher proportions of disinfectant wipes and food yielded HMC product water with higher ammonium concentration. We also compared theoretical chemical composition of HMC product water based on food labels and literature values to experimental results.

  1. Isosteric heats of adsorption for activated carbons made from corn cob

    NASA Astrophysics Data System (ADS)

    Beckner, M.; Olsen, R.; Romanos, J.; Burress, J.; Dohnke, E.; Carter, S.; Casteel, G.; Wexler, C.; Pfeifer, P.

    2010-03-01

    Activated carbons made from corn cob show promise as materials for high-capacity hydrogen storage. As part of our characterization of these materials, we are interested in learning how different production methods affect the adsorption energies. In this talk, we will present experimentally measured isosteric heats of adsorption for various activated carbons calculated using the Clausius-Clayperon equation and hydrogen isotherms at temperatures of 80 and 90K and pressures up to 100 bar measured on a volumetric instrument. We discuss differences observed between isosteric heats determined from Gibbs excess adsorption vs. absolute adsorption curves.

  2. Investigations about the quantitative changes of carbon dioxide production in humans. Report 2: Carbon dioxide production during fever and its relationship with heat production

    NASA Technical Reports Server (NTRS)

    Liebermeister, C.

    1978-01-01

    Investigations are cited and explained for carbon dioxide production during fever and its relationship with heat production. The general topics of discussion are: (1) carbon dioxide production for alternating fever attacks; (2) heat balance during the perspiration phase; (3) heat balance during the chill phase; (4) the theory of fever; and (5) chill phase for other fever attacks.

  3. Heat-activated liposome targeting to streptavidin-coated surfaces.

    PubMed

    Jing, Yujia; Trefná, Hana Dobšíček; Persson, Mikael; Svedhem, Sofia

    2015-06-01

    There is a great need of improved anticancer drugs and corresponding drug carriers. In particular, liposomal drug carriers with heat-activated release and targeting functions are being developed for combined hyperthermia and chemotherapy treatments of tumors. The aim of this study is to demonstrate the heat-activation of liposome targeting to biotinylated surfaces, in model experiments where streptavidin is used as a pretargeting protein. The design of the heat-activated liposomes is based on liposomes assembled in an asymmetric structure and with a defined phase transition temperature. Asymmetry between the inside and the outside of the liposome membrane was generated through the enzymatic action of phospholipase D, where lipid head groups in the outer membrane leaflet, i.e. exposed to the enzyme, were hydrolyzed. The enzymatically treated and purified liposomes did not bind to streptavidin-modified surfaces. When activation heat was applied, starting from 22°C, binding of the liposomes occurred once the temperature approached 33±0.5°C. Moreover, it was observed that the asymmetric structure remained stable for at least 2 weeks. These results show the potential of asymmetric liposomes for the targeted binding to cell membranes in response to (external) temperature stimulus. By using pretargeting proteins, this approach can be further developed for personalized medicine, where tumor-specific antibodies can be selected for the conjugation of pretargeting agents.

  4. Storage-stable foamable polyurethane is activated by heat

    NASA Technical Reports Server (NTRS)

    1966-01-01

    Polyurethane foamable mixture remains inert in storage unit activated to produce a rapid foaming reaction. The storage-stable foamable composition is spread as a paste on the surface of an expandable structure and, when heated, yields a rigid open-cell polyurethane foam that is self-bondable to the substrate.

  5. Singlet oxygen production in Chlamydomonas reinhardtii under heat stress.

    PubMed

    Prasad, Ankush; Ferretti, Ursula; Sedlářová, Michaela; Pospíšil, Pavel

    2016-01-01

    In the current study, singlet oxygen formation by lipid peroxidation induced by heat stress (40 °C) was studied in vivo in unicellular green alga Chlamydomonas reinhardtii. Primary and secondary oxidation products of lipid peroxidation, hydroperoxide and malondialdehyde, were generated under heat stress as detected using swallow-tailed perylene derivative fluorescence monitored by confocal laser scanning microscopy and high performance liquid chromatography, respectively. Lipid peroxidation was initiated by enzymatic reaction as inhibition of lipoxygenase by catechol and caffeic acid prevented hydroperoxide formation. Ultra-weak photon emission showed formation of electronically excited species such as triplet excited carbonyl, which, upon transfer of excitation energy, leads to the formation of either singlet excited chlorophyll or singlet oxygen. Alternatively, singlet oxygen is formed by direct decomposition of hydroperoxide via Russell mechanisms. Formation of singlet oxygen was evidenced by the nitroxyl radical 2,2,6,6-tetramethylpiperidine-1-oxyl detected by electron paramagnetic resonance spin-trapping spectroscopy and the imaging of green fluorescence of singlet oxygen sensor green detected by confocal laser scanning microscopy. Suppression of singlet oxygen formation by lipoxygenase inhibitors indicates that singlet oxygen may be formed via enzymatic lipid peroxidation initiated by lipoxygenase. PMID:26831215

  6. Singlet oxygen production in Chlamydomonas reinhardtii under heat stress

    PubMed Central

    Prasad, Ankush; Ferretti, Ursula; Sedlářová, Michaela; Pospíšil, Pavel

    2016-01-01

    In the current study, singlet oxygen formation by lipid peroxidation induced by heat stress (40 °C) was studied in vivo in unicellular green alga Chlamydomonas reinhardtii. Primary and secondary oxidation products of lipid peroxidation, hydroperoxide and malondialdehyde, were generated under heat stress as detected using swallow-tailed perylene derivative fluorescence monitored by confocal laser scanning microscopy and high performance liquid chromatography, respectively. Lipid peroxidation was initiated by enzymatic reaction as inhibition of lipoxygenase by catechol and caffeic acid prevented hydroperoxide formation. Ultra-weak photon emission showed formation of electronically excited species such as triplet excited carbonyl, which, upon transfer of excitation energy, leads to the formation of either singlet excited chlorophyll or singlet oxygen. Alternatively, singlet oxygen is formed by direct decomposition of hydroperoxide via Russell mechanisms. Formation of singlet oxygen was evidenced by the nitroxyl radical 2,2,6,6-tetramethylpiperidine-1-oxyl detected by electron paramagnetic resonance spin-trapping spectroscopy and the imaging of green fluorescence of singlet oxygen sensor green detected by confocal laser scanning microscopy. Suppression of singlet oxygen formation by lipoxygenase inhibitors indicates that singlet oxygen may be formed via enzymatic lipid peroxidation initiated by lipoxygenase. PMID:26831215

  7. Efficacy of oral administration of heat-killed probiotics from Mongolian dairy products against influenza infection in mice: alleviation of influenza infection by its immunomodulatory activity through intestinal immunity.

    PubMed

    Takeda, Shiro; Takeshita, Masahiko; Kikuchi, Yukiharu; Dashnyam, Bumbein; Kawahara, Satoshi; Yoshida, Hiroki; Watanabe, Wataru; Muguruma, Michio; Kurokawa, Masahiko

    2011-12-01

    Some probiotics possess immunomodulatory activities and have been used as complementary and alternative medicines. We previously found that 10 lactic acid bacteria (LAB) strains isolated from traditional Mongolian dairy products showed probiotic potential in vitro. In this study, we assessed the immunomodulatory activity of 10 LABs on influenza virus (IFV) infection in relation to their efficacies in IFV-infected mice. In an intranasal IFV infection model in mice, oral administration of boiled Lactobacillus plantarum 06CC2 strain (20mg/mouse), one of the 10 LABs, twice daily for 10 days starting two days before infection was significantly effective in protecting the body weight loss of infected mice, reducing virus yields in the lungs on days 2, 4, and 6 after infection, and prolonging survival times without toxicity. The total numbers of infiltrated cells in the bronchoalveolar lavage fluid (BALF), especially macrophages and neutrophils, were significantly reduced by 06CC2 administration on day 2. On day 2, tumor necrosis factor (TNF)-α production in BALF was also reduced significantly, but interferon-α, interleukin-12, and interferon-γ productions were augmented and natural killer (NK) cell activity was significantly elevated. Furthermore, the gene expressions of interleukin-12 receptor and interferon-γ in Peyer's patches were augmented by 06CC2 administration on day 2. Thus, 06CC2 was suggested to alleviate influenza symptoms in mice in correlation with the augmentation of NK cell activity associated with the enhancement of interferon-α and Th1 cytokine productions through intestinal immunity and the reduction of TNF-α in the early stage of infection.

  8. Diagnostics of Coronal Heating in Solar Active Regions

    NASA Astrophysics Data System (ADS)

    Fludra, Andrzej; Hornsey, Christopher; Nakariakov, Valery

    2015-04-01

    We aim to develop a diagnostic method for the coronal heating mechanism in active region loops. Observational constraints on coronal heating models have been sought using measurements in the X-ray and EUV wavelengths. Statistical analysis, using EUV emission from many active regions, was done by Fludra and Ireland (2008) who studied power-law relationships between active region integrated magnetic flux and emission line intensities. A subsequent study by Fludra and Warren (2010) for the first time compared fully resolved images in an EUV spectral line of OV 63.0 nm with the photospheric magnetic field, leading to the identification of a dominant, ubiquitous variable component of the transition region EUV emission and a discovery of a steady basal heating, and deriving the dependence of the basal heating rate on the photospheric magnetic flux density. In this study, we compare models of single coronal loops with EUV observations. We assess to what degree observations of individual coronal loops made in the EUV range are capable of providing constraints on the heating mechanism. We model the coronal magnetic field in an active region using an NLFF extrapolation code applied to a photospheric vector magnetogram from SDO/HMI and select several loops that match an SDO/AIA 171 image of the same active region. We then model the plasma in these loops using a 1D hydrostatic code capable of applying an arbitrary heating rate as a function of magnetic field strength along the loop. From the plasma parameters derived from this model, we calculate the EUV emission along the loop in AIA 171 and 335 bands, and in pure spectral lines of Fe IX 17.1 nm and Fe XVI 33.5 nm. We use different spatial distributions of the heating function: concentrated near the loop top, uniform and concentrated near the footpoints, and investigate their effect on the modelled EUV intensities. We find a diagnostics based on the dependence of the total loop intensity on the shape of the heating function

  9. SHUTTLE-STREAMING: SYNCHRONIZATION WITH HEAT PRODUCTION IN SLIME MOLD.

    PubMed

    ALLEN, R D; PITTS, W R; SPEIR, D; BRAULT, J

    1963-12-13

    Two small blobs and a channel excised from a slime mold plasmodium were allowed to fuse into a dumbbell-shaped mass in a thermally insulated Kamiya double chamber equipped with naked bead thermistors in contact with the blobs. Cyclic temperature differences of from 1 X 10(-4) to 5 X 10(-2) deg Celsius were recorded by a sensitive lock-in amplifier method with a basal noise level of less than 2 X 10(-2)deg Celsius and a time constant of 0.5 second. The temperature differences were caused by periodic bursts of heat production synchronized perfectly with the shuttle-streaming cycle and invariably localized at the source rather than the destination of the streaming cytoplasm. The results support the theory that the motive force for cytoplasmic streaming in the slime mold is pressure, probably generated by contraction of elements in the channel walls.

  10. A Fresnel collector process heat experiment at Capitol Concrete Products

    NASA Technical Reports Server (NTRS)

    Hauger, J. S.

    1981-01-01

    An experiment is planned, conducted and evaluated to determine the feasibility of using a Power Kinetics' Fresnel concentrator to provide process heat in an industrial environment. The plant provides process steam at 50 to 60 psig to two autoclaves for curing masonry blocks. When steam is not required, the plant preheats hot water for later use. A second system is installed at the Jet Propulsion Laboratory parabolic dish test site for hardware validation and experiment control. Experiment design allows for the extrapolation of results to varying demands for steam and hot water, and includes a consideration of some socio-technical factors such as the impact on production scheduling of diurnal variations in energy availability.

  11. Active heat exchange system development for latent heat thermal energy storage

    NASA Astrophysics Data System (ADS)

    Lefrois, R. T.

    1980-03-01

    Alternative mechanizations of active heat exchange concepts were analyzed for use with heat of fusion Phase Change Materials (PCM's) in the temperature range of 250 C to 350 C for solar and conventional power plant applications. Over 24 heat exchange concepts were reviewed, and eight were selected for detailed assessment. Two candidates were chosen for small-scale experimentation: a coated tube and shell that exchanger, and a direct contact reflux boiler. A dilute eutectic mixture of sodium nitrate and sodium hydroxide was selected as the PCM from over fifty inorganic salt mixtures investigated. Preliminary experiments with various tube coatings indicated that a nickel or chrome plating of Teflon or Ryton coating had promise of being successful. An electroless nickel plating was selected for further testing. A series of tests with nickel-plated heat transfer tubes showed that the solidifying sodium nitrate adhered to the tubes and the experiment failed to meet the required discharge heat transfer rate of 10 kW(t). Testing of the reflux boiler is under way.

  12. Active heat exchange system development for latent heat thermal energy storage

    NASA Technical Reports Server (NTRS)

    Lefrois, R. T.

    1980-01-01

    Alternative mechanizations of active heat exchange concepts were analyzed for use with heat of fusion Phase Change Materials (PCM's) in the temperature range of 250 C to 350 C for solar and conventional power plant applications. Over 24 heat exchange concepts were reviewed, and eight were selected for detailed assessment. Two candidates were chosen for small-scale experimentation: a coated tube and shell that exchanger, and a direct contact reflux boiler. A dilute eutectic mixture of sodium nitrate and sodium hydroxide was selected as the PCM from over fifty inorganic salt mixtures investigated. Preliminary experiments with various tube coatings indicated that a nickel or chrome plating of Teflon or Ryton coating had promise of being successful. An electroless nickel plating was selected for further testing. A series of tests with nickel-plated heat transfer tubes showed that the solidifying sodium nitrate adhered to the tubes and the experiment failed to meet the required discharge heat transfer rate of 10 kW(t). Testing of the reflux boiler is under way.

  13. The reliability of a heat acclimation state test prescribed from metabolic heat production intensities.

    PubMed

    Willmott, A G B; Hayes, M; Dekerle, J; Maxwell, N S

    2015-10-01

    Acclimation state indicates an individual's phenotypic response to a thermally stressful environment, where changes in heat dissipation capacity are determined during a heat acclimation state test (HAST). Variations in thermoregulatory and sudomotor function are reported while exercising at intensities relative to maximal oxygen uptake. This inter-individual variation is not true when intensity is prescribed to elicit a fixed rate of metabolic heat production (Ḣprod). This study investigated the reliability of peak Tre and two composite measures (sweat gain and sweat setpoint) derived from indices of thermosensitivity during a HAST prescribed from Ḣprod intensities. Fourteen participants (mean±SD; age 23±3 years, stature 174±7cm, body mass 75.0±9.4kg, body surface area 1.9±0.1m(2), peak oxygen consumption [V̇O2peak] 3.49±0.53Lmin(-1)) completed a lactate threshold-V̇O2peak test and two duplicate Ḣprod HASTs on a cycle ergometer. The HAST consisted of three, 30-min periods of exercise at fixed Ḣprod intensities relative to body mass (3, 4.5 and 6Wkg(-1)), within hot dry conditions (44.7±1.8°C and 18.1±4.7% relative humidity). Peak Tre (38.20±0.36 vs. 38.16±0.42°C, p=0.54), sweat setpoint (36.76±0.34 and 36.79±0.38°C, p=0.68) and sweat gain (0.37±0.14 and 0.40±0.18gs(-1)°C(-1), p=0.40) did not differ between HASTs. Typical error of measurement (TEM), coefficient variation (CV) and intra-class coefficient of correlation (ICC) were 0.19°C, 0.5% and 0.80 for peak Tre, 0.21°C, 0.6% and 0.65 for sweat setpoint and 0.09gs(-1)°C(-1), 28% and 0.68 for sweat gain, respectively. The use of fixed Ḣprod intensities relative to body mass is a reliable method for measuring Tre and ascertaining sweat setpoint during a HAST, whereas, sweat gain displays greater variability. A Ḣprod HAST appears sufficiently reliable for quantifying heat acclimation state, where TEM in peak Tre and sweat setpoint are small enough to identify physiologically

  14. Active heat exchange system development for latent heat thermal energy storage

    NASA Technical Reports Server (NTRS)

    Alario, J.; Kosson, R.; Haslett, R.

    1980-01-01

    Various active heat exchange concepts were identified from among three generic categories: scrapers, agitators/vibrators and slurries. The more practical ones were given a more detailed technical evaluation and an economic comparison with a passive tube-shell design for a reference application (300 MW sub t storage for 6 hours). Two concepts were selected for hardware development: (1) a direct contact heat exchanger in which molten salt droplets are injected into a cooler counterflowing stream of liquid metal carrier fluid, and (2) a rotating drum scraper in which molten salt is sprayed onto the circumference of a rotating drum, which contains the fluid salt is sprayed onto the circumference of a rotating drum, which contains the fluid heat sink in an internal annulus near the surface. A fixed scraper blade removes the solidified salt from the surface which was nickel plated to decrease adhesion forces. In addition to improving performance by providing a nearly constant transfer rate during discharge, these active heat exchanger concepts were estimated to cost at least 25% less than the passive tube-shell design.

  15. A mathematical model of heat flow in a thermopile for measuring muscle heat production: implications for design and signal analysis.

    PubMed

    Barclay, C J

    2015-09-01

    Contracting muscles produce heat which largely arises from the biochemical reactions that provide the energy for contraction. Measurements of muscle heat production have made, and continue to make, important contributions to our understanding of the bases of contraction. Most measurements of muscle heat production are made using a thermopile, consisting of a series of thermocouples arranged so that alternate thermocouples are in thermal contact with the muscle and with an isothermal reference. In this study, a mathematical model was constructed of a muscle lying on a thermopile consisting of antimony-bismuth thermocouples sandwiched between polymer sheets. The validity of the model was demonstrated by its ability to accurately predict thermopile outputs in response to applying heat to the thermopile surface, to generating heat in the thermocouples using the Peltier effect and to adding heat capacity on the thermopile surface. The model was then used to show how practical changes to thermopile construction could minimise response time and thermopile heat capacity and allow measurement of very low rates of heat production. The impulse response of a muscle-thermopile system was generated using the model and used to illustrate how a measured signal can be deconvolved with the impulse response to correct for lag introduced by the thermopile. PMID:26234299

  16. A mathematical model of heat flow in a thermopile for measuring muscle heat production: implications for design and signal analysis.

    PubMed

    Barclay, C J

    2015-09-01

    Contracting muscles produce heat which largely arises from the biochemical reactions that provide the energy for contraction. Measurements of muscle heat production have made, and continue to make, important contributions to our understanding of the bases of contraction. Most measurements of muscle heat production are made using a thermopile, consisting of a series of thermocouples arranged so that alternate thermocouples are in thermal contact with the muscle and with an isothermal reference. In this study, a mathematical model was constructed of a muscle lying on a thermopile consisting of antimony-bismuth thermocouples sandwiched between polymer sheets. The validity of the model was demonstrated by its ability to accurately predict thermopile outputs in response to applying heat to the thermopile surface, to generating heat in the thermocouples using the Peltier effect and to adding heat capacity on the thermopile surface. The model was then used to show how practical changes to thermopile construction could minimise response time and thermopile heat capacity and allow measurement of very low rates of heat production. The impulse response of a muscle-thermopile system was generated using the model and used to illustrate how a measured signal can be deconvolved with the impulse response to correct for lag introduced by the thermopile.

  17. Heated Proteins are Still Active in a Functionalized Nanoporous Support

    SciTech Connect

    Chen, Baowei; Qi, Wen N.; Li, Xiaolin; Lei, Chenghong; Liu, Jun

    2013-07-08

    We report that even under the heated condition, the conformation and activity of a protein can be hoarded in a functionalized nanoporous support via non-covalent interaction, although the hoarded protein was not exhibiting the full protein activity, the protein released subsequently still maintained its native conformation and activity. Glucose oxidase (GOX) was spontaneously and largely entrapped in aminopropyl-functionalized mesoporous silica (NH2-FMS) at 20 oC via a dominant electrostatic interaction. Although FMS-GOX displayed 45% activity of the free enzyme in solution, the GOX released from FMS exhibited its 100% activity prior to the entrapment. Surprisingly, the released GOX from FMS still maintained 89% of its initial activity prior to the entrapment after FMS-GOX was incubated at 60 oC for 1 h prior to release, while the free GOX in solution lost nearly all activity under the same incubation. Intrinsic fluorescence emission of GOX and native electrophoresis demonstrated that the heating resulted in significant conformational changes and oligomeric structures of the free GOX, but FMS efficiently maintained the thermal stability of GOX therein and resisted the thermal denaturation and oligomeric aggregation.

  18. A flexible RF applicator for heating viscous lossy products such as foods.

    PubMed

    Roussy, G; Streiff, F; Moneuse, M

    2001-01-01

    A helical RF industrial applicator was evaluated for heating minced meat flowing in a hollow tube. Heating was homogeneous inside the product, although the product was highly lossy due to its high electric conductivity. The homogeneity was much better than could be obtained with microwave heating. A high power density, up to 5 kW/liter, can be deposited inside the product with 95% efficiency.

  19. Laser-heating-based active optics for synchrotron radiation applications.

    PubMed

    Yang, Fugui; Li, Ming; Gao, Lidan; Sheng, Weifan; Liu, Peng; Zhang, Xiaowei

    2016-06-15

    Active optics has attracted considerable interest from researchers in synchrotron radiation facilities because of its capacity for x-ray wavefront correction. Here, we report a novel and efficient technique for correcting or modulating a mirror surface profile based on laser-heating-induced thermal expansion. An experimental study of the characteristics of the surface thermal deformation response indicates that the power of a milliwatt laser yields a bump height as low as the subnanometer scale and that the variation of the spot size modulates the response function width effectively. In addition, the capacity of the laser-heating technique for free-form surface modulation is demonstrated via a one-dimensional surface correction experiment. The developed method is a promising new approach toward effective x-ray active optics coupled with at-wavelength metrology techniques.

  20. Laser-heating-based active optics for synchrotron radiation applications.

    PubMed

    Yang, Fugui; Li, Ming; Gao, Lidan; Sheng, Weifan; Liu, Peng; Zhang, Xiaowei

    2016-06-15

    Active optics has attracted considerable interest from researchers in synchrotron radiation facilities because of its capacity for x-ray wavefront correction. Here, we report a novel and efficient technique for correcting or modulating a mirror surface profile based on laser-heating-induced thermal expansion. An experimental study of the characteristics of the surface thermal deformation response indicates that the power of a milliwatt laser yields a bump height as low as the subnanometer scale and that the variation of the spot size modulates the response function width effectively. In addition, the capacity of the laser-heating technique for free-form surface modulation is demonstrated via a one-dimensional surface correction experiment. The developed method is a promising new approach toward effective x-ray active optics coupled with at-wavelength metrology techniques. PMID:27304296

  1. Visible light active photocatalyst from recycled disposable heating pads

    NASA Astrophysics Data System (ADS)

    Lee, Meng-Chien; Wang, Chun-Yu; Chen, Che-Chin; Wang, Chih-Ming; Hsiao, Ta-Chih; Tsai, Din Ping

    2016-01-01

    Alpha-Fe2O3 (α-Fe2O3) is cheap and abundant and has potential to be a highly efficient photocatalyst for water splitting. According to the report, there are a huge amount of disposable heating pads being created every year, and the pads are used one time then thrown away. We found that the main product of used heating pads is α-Fe2O3. Here, we collect and purify the α-Fe2O3 powder in the used heating pads using low power consumption processes. It is shown that the recycled heating pads can be used as a cost-effective photocatalyst for H2 energy and for decomposition of organic pollutants as well. Additionally, the plasmonic enhanced photocatalysis reaction of α-Fe2O3 is also investigated. It is found that H2 evolution rate can be enhanced 15% using α-Fe2O3 nanoparticles coated with a thin Au layer. The degradation of methylene blue can also enhance 12% compared to photocatalyst α-Fe2O3 nanoparticles coated without Au layer.

  2. Heat production of pig platelets in relation with glycolysis and respiration.

    PubMed

    Nanri, H; Minakami, S

    1983-01-01

    Heat production of pig platelets was measured on a flow microcalorimeter with simultaneous measurements of the oxygen consumption and metabolite change of the suspension. The heat production associated with the glycolytic reaction was estimated from the decrease in the heat production caused by the addition of sodium fluoride. The glycolytic heat production was about -75 kJ per mol of lactate formed, which is the sum of the enthalpy values for the conversion of glucose to lactic acid and that for the neutralization of the acid. The heat production due to the respiration was estimated from the heat production of the cells at various pH. The respiratory heat production was about -475 kJ per mol oxygen consumed, which agrees with the enthalpy change for the non-phosphorylating respiration of mitochondria or for the complete oxidation of glucose or fatty acids. The heat production of the cells increased by the alkalinization of the medium, and the increase of the heat production was parallel with the increase in the lactate formation.

  3. Relation between cell death progression, reactive oxygen species production and mitochondrial membrane potential in fermenting Saccharomyces cerevisiae cells under heat-shock conditions.

    PubMed

    Pyatrikas, Darya V; Fedoseeva, Irina V; Varakina, Nina N; Rusaleva, Tatyana M; Stepanov, Alexei V; Fedyaeva, Anna V; Borovskii, Gennadii B; Rikhvanov, Eugene G

    2015-06-01

    Moderate heat shock increased reactive oxygen species (ROS) production that led to cell death in glucose-grown Saccharomyces cerevisiae cells. Conditions that disturb mitochondrial functions such as treatment by uncouplers and petite mutation were shown to inhibit ROS production and protects cell from thermal death. Hence, mitochondria are responsible for ROS production and play an active role in cell death. An increase in ROS production was accompanied by hyperpolarization of inner mitochondrial membrane. All agents suppressing hyperpolarization also suppressed heat-induced ROS production. It was supposed that generation of ROS under moderate heat shock in glucose-grown S. cerevisiae cells is driven by the mitochondrial membrane potential.

  4. Constructing a model of 3D radiogenic heat production in Ireland

    NASA Astrophysics Data System (ADS)

    Willmot Noller, N. M.; Daly, J. S.

    2012-04-01

    Heat production values in the crust and mantle rock inform heat flow density data to provide crucial information about the structure of the Earth's lithosphere. In addition, accurate models of horizontal and vertical distribution of heat production can help to define geothermal exploration targets. Low-enthalpy district scale space heating and Enhanced Geothermal Systems (EGS) using hot, dry rock may provide sustainable energy resources in regions currently perceived as having low geothermal energy potential. Ireland is located within stable lithosphere, unaffected by recent tectonism and volcanism, and has an estimated heat flow range below the measured global continental average. Nevertheless, borehole data indicate that heat production is variable across the island, with anomalously high rates observed, for example, in Cavan, Meath and Antrim. Data coverage is, however, poor. Radioactive isotopic decay generates heat in rock. By using established heat production constants and known concentrations of unstable isotopes of uranium, thorium and potassium, along with rock density values, a heat production rate in μW m -3 is obtained. With the objective of compiling the first comprehensive database of information about the Irish lithosphere, in three dimensions, the authors present here initial results obtained from published and unpublished whole-rock major and trace element analyses. The presence of systematic trends correlating heat production to properties such as age and lithology are also investigated. Offering insight into the vertical component of heat production distribution, Irish xenoliths emplaced in Lower Carboniferous volcanics are regarded as a reliable proxy for the present-day lower crust. Their geochemical composition gives heat production values that are higher than expected for the depths indicated by their thermobarometric data, suggesting that heat production rates do not simply reduce with depth.

  5. Retrieved Vertical Profiles of Latent Heat Release Using TRMM Rainfall Products

    NASA Technical Reports Server (NTRS)

    Tao, W.-K.; Lang, S.; Olson, W. S.; Meneghini, R.; Yang, S.; Simpson, J.; Kummerow, C.; Smith, E.

    2000-01-01

    This paper represents the first attempt to use TRMM rainfall information to estimate the four dimensional latent heating structure over the global tropics for February 1998. The mean latent heating profiles over six oceanic regions (TOGA COARE IFA, Central Pacific, S. Pacific Convergence Zone, East Pacific, Indian Ocean and Atlantic Ocean) and three continental regions (S. America, Central Africa and Australia) are estimated and studied. The heating profiles obtained from the results of diagnostic budget studies over a broad range of geographic locations are used to provide comparisons and indirect validation for the heating algorithm estimated heating profiles. Three different latent heating algorithms, the Goddard Convective-Stratiform (CSH) heating, the Goddard Profiling (GPROF) heating, and the Hydrometeor heating (HH) are used and their results are intercompared. The horizontal distribution or patterns of latent heat release from the three different heating retrieval methods are quite similar. They all can identify the areas of major convective activity (i.e., a well defined ITCZ in the Pacific, a distinct SPCZ) in the global tropics. The magnitude of their estimated latent heating release is also not in bad agreement with each other and with those determined from diagnostic budget studies. However, the major difference among these three heating retrieval algorithms is the altitude of the maximum heating level. The CSH algorithm estimated heating profiles only show one maximum heating level, and the level varies between convective activity from various geographic locations. These features are in good agreement with diagnostic budget studies. By contrast, two maximum heating levels were found using the GPROF heating and HH algorithms. The latent heating profiles estimated from all three methods can not show cooling between active convective events. We also examined the impact of different TMI (Multi-channel Passive Microwave Sensor) and PR (Precipitation Radar

  6. Glycosylation and Activities of Natural Products.

    PubMed

    Huang, Gangliang; Lv, Meijiao; Hu, Jinchuan; Huang, Kunlin; Xu, Hong

    2016-01-01

    Natural products are widely found in nature, their number and variety are numerous, the structures are complex and diverse. These natural products have many physiological and pharmacological activities. Glycosylation can increase the diversity of structure and function of natural product, it has become the focus of drug research and development. The impacts of glycosylation of natural products to water solubility, pharmacological activities, bioavailability, or others were described in this review, which provides a reference for the development and application of glycosylated natural products. PMID:27499190

  7. Effects of heat stress on serum insulin, adipokines, AMP-activated protein kinase, and heat shock signal molecules in dairy cows.

    PubMed

    Min, Li; Cheng, Jian-bo; Shi, Bao-lu; Yang, Hong-jian; Zheng, Nan; Wang, Jia-qi

    2015-06-01

    Heat stress affects feed intake, milk production, and endocrine status in dairy cows. The temperature-humidity index (THI) is employed as an index to evaluate the degree of heat stress in dairy cows. However, it is difficult to ascertain whether THI is the most appropriate measurement of heat stress in dairy cows. This experiment was conducted to investigate the effects of heat stress on serum insulin, adipokines (leptin and adiponectin), AMP-activated protein kinase (AMPK), and heat shock signal molecules (heat shock transcription factor (HSF) and heat shock proteins (HSP)) in dairy cows and to research biomarkers to be used for better understanding the meaning of THI as a bioclimatic index. To achieve these objectives, two experiments were performed. The first experiment: eighteen lactating Holstein dairy cows were used. The treatments were: heat stress (HS, THI average=81.7, n=9) and cooling (CL, THI average=53.4, n=9). Samples of HS were obtained on August 16, 2013, and samples of CL were collected on April 7, 2014 in natural conditions. The second experiment: HS treatment cows (n=9) from the first experiment were fed for 8 weeks from August 16, 2013 to October 12, 2013. Samples for moderate heat stress, mild heat stress, and no heat stress were obtained, respectively, according to the physical alterations of the THI. Results showed that heat stress significantly increased the serum adiponectin, AMPK, HSF, HSP27, HSP70, and HSP90 (P<0.05). Adiponectin is strongly associated with AMPK. The increases of adiponectin and AMPK may be one of the mechanisms to maintain homeostasis in heat-stressed dairy cows. When heat stress treatment lasted 8 weeks, a higher expression of HSF and HSP70 was observed under moderate heat stress. Serum HSF and HSP70 are sensitive and accurate in heat stress and they could be potential indicators of animal response to heat stress. We recommend serum HSF and HSP70 as meaningful biomarkers to supplement the THI and evaluate moderate heat

  8. Evaluation of the isosteric heat of adsorption at zero coverage for hydrogen on activated carbons

    NASA Astrophysics Data System (ADS)

    Dohnke, E.; Beckner, M.; Romanos, J.; Olsen, R.; Wexler, C.; Pfeifer, P.

    2011-03-01

    Activated carbons made from corn cob show promise as materials for high-capacity hydrogen storage. As part of our characterization of these materials, we are interested in learning how different production methods affect the adsorption energies. In this talk, we will show how hydrogen adsorption isotherms may be used to calculate these adsorption energies at zero coverage using Henry's law. We will additionally discuss differences between the binding energy and the isosteric heat of adsorption by applying this analysis at different temperatures.

  9. Thermal Gains Through Collective Metabolic Heat Production in Social Caterpillars of Eriogaster lanestris

    NASA Astrophysics Data System (ADS)

    Ruf, C.; Fiedler, K.

    We investigated thermal characteristics of aggregations of social, tent-building caterpillars of the small eggar moth Eriogaster lanestris (Lepidoptera: Lasiocampidae). The highly synchronous behavior of individuals of the colony has important consequences for their thermal ecology. Air temperature in the tent fluctuates according to the caterpillars' activity: air temperature slowly rises about 2.5-3 °C above the surroundings when caterpillars aggregate in the tent after feeding and decreases rapidly when the larvae leave the tent. Thermal energy can be stored for a few hours when ambient temperature drops. Experiments show that metabolic heat production sufficiently explains this effect. As even minor additional heat gain may reduce developmental time, aggregating in the tent may thus confer selective advantages under overcast weather or at night, when behavioral thermoregulation through basking is not possible.

  10. Climate change, workplace heat exposure, and occupational health and productivity in Central America.

    PubMed

    Kjellstrom, Tord; Crowe, Jennifer

    2011-01-01

    Climate change is increasing heat exposure in places such as Central America, a tropical region with generally hot/humid conditions. Working people are at particular risk of heat stress because of the intrabody heat production caused by physical labor. This article aims to describe the risks of occupational heat exposure on health and productivity in Central America, and to make tentative estimates of the impact of ongoing climate change on these risks. A review of relevant literature and estimation of the heat exposure variable wet bulb globe temperature (WBGT) in different locations within the region were used to estimate the effects. We found that heat stress at work is a real threat. Literature from Central America and heat exposure estimates show that some workers are already at risk under current conditions. These conditions will likely worsen with climate change, demonstrating the need to create solutions that will protect worker health and productivity.

  11. Investigation of heat treating conditions for enhancing the anti-inflammatory activity of citrus fruit (Citrus reticulata) peels.

    PubMed

    Ho, Su-Chen; Lin, Chih-Cheng

    2008-09-10

    In traditional Chinese medicine, dried citrus fruit peels are widely used as remedies to alleviate coughs and reduce phlegm in the respiratory tract. Induction of inducible nitric oxide synthase (iNOS) in inflammatory cells and increased airway production of nitric oxide (NO) are well recognized as key events in inflammation-related respiratory tract diseases. Despite the fact that the enhancing effect of heat treatment on the antioxidant activity of citrus fruit peels has been well documented, the impact of heat treatment on citrus peel beneficial activities regarding anti-inflammation is unclear. To address this issue, we determined the anti-inflammatory activities of heat-treated citrus peel extracts by measuring their inhibitory effect upon NO production by lipopolysaccharide-activated RAW 264.7 macrophages. Results showed that the anti-inflammatory activity of citrus peel was significantly elevated after 100 degrees C heat treatment in a time-dependent fashion during a period from 0 to 120 min. Inhibition of iNOS gene expression was the major NO-suppressing mechanism of the citrus peel extract. Additionally, the anti-inflammatory activity of citrus peel extract highly correlated with the content of nobiletin and tangeretin. Conclusively, proper and reasonable heat treatment helped to release nobiletin and tangeretin, which were responsible for the increased anti-inflammatory activity of heat-treated citrus peels. PMID:18683945

  12. Production of activated carbon from TCR char

    NASA Astrophysics Data System (ADS)

    Stenzel, Fabian; Heberlein, Markus; Klinner, Tobias; Hornung, Andreas

    2016-04-01

    The utilization of char for adsorptive purposes is known since the 18th century. At that time the char was made of wood or bones and used for decoloration of fluids. In the 20th century the production of activated carbon in an industrial scale was started. The today's raw materials for activated carbon production are hard coal, peat, wood or coconut shells. All these materials entail costs especially the latter. Thus, the utilization of carbon rich residues (biomass) is an interesting economic opportunity because it is available for no costs or even can create income. The char is produced by thermo-catalytic reforming (TCR®). This process is a combination of an intermediate pyrolysis and subsequently a reforming step. During the pyrolysis step the material is decomposed in a vapor and a solid carbon enriched phase. In the second step the vapor and the solid phase get in an intensive contact and the quality of both materials is improved via the reforming process. Subsequently, the condensables are precipitated from the vapor phase and a permanent gas as well as oil is obtained. Both are suitable for heat and power production which is a clear advantage of the TCR® process. The obtained biochar from the TCR® process has special properties. This material has a very low hydrogen and oxygen content. Its stability is comparable to hard coal or anthracite. Therefore it consists almost only of carbon and ash. The latter depends from input material. Furthermore the surface structure and area can be influenced during the reforming step. Depending from temperature and residence time the number of micro pores and the surface area can be increased. Preliminary investigations with methylene blue solution have shown that a TCR® char made of digestate from anaerobic digestion has adsorptive properties. The decoloration of the solution was achieved. A further influencing factor of the adsorption performance is the particle size. Based on the results of the preliminary tests a

  13. Numerical modeling of compact high temperature heat exchanger and chemical decomposer for hydrogen production

    NASA Astrophysics Data System (ADS)

    Ponyavin, Valery; Chen, Yitung; Hechanova, Anthony E.; Wilson, Merrill

    2008-09-01

    The present study addresses fluid flow and heat transfer in a high temperature compact heat exchanger which will be used as a chemical decomposer in a hydrogen production plant. The heat exchanger is manufactured using fused ceramic layers that allow creation of channels with dimensions below 1 mm. The main purpose of this study is to increase the thermal performance of the heat exchanger, which can help to increase the sulfuric acid decomposition rate. Effects of various channel geometries of the heat exchanger on the pressure drop are studied as well. A three-dimensional computational model is developed for the investigation of fluid flow and heat transfer in the heat exchanger. Several different geometries of the heat exchanger channels, such as straight channels, ribbed ground channels, hexagonal channels, and diamond-shaped channels are examined. Based on the results, methods on how to improve the design of the heat exchanger are recommended.

  14. Production of concrete articles utilizing heat-reclaiming system

    SciTech Connect

    Wauhop Jr., B. J.; Stratz, W. W.

    1985-07-30

    A method of producing concrete articles comprises reclaiming a portion of the heat energy from the kiln atmosphere during the curing of the concrete articles, and then utilizing the reclaimed heat energy to pre-heat mixing water used to form other concrete articles, or to add to boiler feed water used to generate low pressure steam, or both. In the case where two or more kilns are operated simultaneously at staggered curing cycles, the high temperature kiln atmosphere from the kiln undergoing cool down is intermixed with the low temperature kiln atmosphere from the kiln undergoing heat up thereby reclaiming heat energy from one kiln and using it in the other kiln thereby reducing the total energy consumption required for curing.

  15. Active heat exchange system development for latent heat thermal energy storage

    NASA Astrophysics Data System (ADS)

    Alario, J.; Haslett, R.

    1980-03-01

    Various active heat exchange concepts were identified from among three generic categories: scrapers, agitators/vibrators and slurries. The more practical ones were given a more detailed technical evaluation and an economic comparison with a passive tube-shell design for a reference application. Two concepts selected for hardware development are a direct contact heat exchanger in which molten salt droplets are injected into a cooler counterflowing stream of liquid metal carrier fluid, and a rotating drum scraper in which molten salt is sprayed onto the circumference of a rotating drum, which contains the fluid heat sink in an internal annulus near the surface. A fixed scraper blade removes the solidified salt from the surface which has been nickel plated to decrease adhesion forces. Suitable phase change material (PCM) storage media with melting points in the temperature range of interest (250 C to 400 C) were investigated. The specific salt recommended for laboratory tests was a chloride eutectic (20.5KCl-24/5 NaCl-55.0MgCl 2% by wt.), with a nominal melting point of 385 C.

  16. Active heat exchange system development for latent heat thermal energy storage

    NASA Technical Reports Server (NTRS)

    Alario, J.; Haslett, R.

    1980-01-01

    Various active heat exchange concepts were identified from among three generic categories: scrapers, agitators/vibrators and slurries. The more practical ones were given a more detailed technical evaluation and an economic comparison with a passive tube-shell design for a reference application. Two concepts selected for hardware development are a direct contact heat exchanger in which molten salt droplets are injected into a cooler counterflowing stream of liquid metal carrier fluid, and a rotating drum scraper in which molten salt is sprayed onto the circumference of a rotating drum, which contains the fluid heat sink in an internal annulus near the surface. A fixed scraper blade removes the solidified salt from the surface which has been nickel plated to decrease adhesion forces. Suitable phase change material (PCM) storage media with melting points in the temperature range of interest (250 C to 400 C) were investigated. The specific salt recommended for laboratory tests was a chloride eutectic (20.5KCl-24/5 NaCl-55.0MgCl 2% by wt.), with a nominal melting point of 385 C.

  17. Turbokon scientific and production implementation company—25 years of activity

    NASA Astrophysics Data System (ADS)

    Favorskii, O. N.; Leont'ev, A. I.; Milman, O. O.

    2016-05-01

    The main results of studies performed at ZAO Turbokon NPVP in cooperation with leading Russian scientific organizations during 25 years of its activity in the field of development of unique ecologically clean electric power and heat production technologies are described. They include the development and experimental verification using prototypes and full-scale models of highly efficient air-cooled condensers for steam turbines, a high temperature gas steam turbine for stationary and transport power engineering, a nonfuel technology of electric power production using steam turbine installations with a unit power of 4-20 MW at gas-main pipelines and industrial boiler houses and heat stations. The results of efforts in the field of reducing vibroactivity of power equipment for transport installations are given. Basic directions of further research for increasing the efficiency and ecological safety of home power engineering are discussed.

  18. Heating of thin products by means of transverse-flux inductors

    NASA Astrophysics Data System (ADS)

    1980-02-01

    There are some forms of metallic products which do not lend themselves well to induction heating upon first consideration, either because of their shape (small thickness) or their nature (materials with low resistance). In particular, this applies to all products in the form of a thin sheet. Various applications are suggested such as the drying of the sheet after pickling the heating of the sheet in order to dry or harden varnish lacquer, and the heat treatment of aluminium sheet.

  19. Radiogenic heat production in sedimentary rocks of the Gulf of Mexico Basin, south Texas

    USGS Publications Warehouse

    McKenna, T.E.; Sharp, J.M.

    1998-01-01

    Radiogenic heat production within the sedimentary section of the Gulf of Mexico basin is a significant source of heat. Radiogenic heat should be included in thermal models of this basin (and perhaps other sedimentary basins). We calculate that radiogenic heat may contribute up to 26% of the overall surface heat-flow density for an area in south Texas. Based on measurements of the radioactive decay rate of ??-particles, potassium concentration, and bulk density, we calculate radiogenic heat production for Stuart City (Lower Cretaceous) limestones, Wilcox (Eocene) sandstones and mudrocks, and Frio (Oligocene) sandstones and mudrocks from south Texas. Heat production rates range from a low of 0.07 ?? 0.01 ??W/m3 in clean Stuart City limestones to 2.21 ?? 0.24??W/m3 in Frio mudrocks. Mean heat production rates for Wilcox sandstones, Frio sandstones, Wilcox mudrocks, and Frio mudrocks are 0.88, 1.19, 1.50, and 1.72 ??W/m3, respectively. In general, the mudrocks produce about 30-40% more heat than stratigraphically equivalent sandstones. Frio rocks produce about 15% more heat than Wilcox rocks per unit volume of clastic rock (sandstone/mudrock). A one-dimensional heat-conduction model indicates that this radiogenic heat source has a significant effect on subsurface temperatures. If a thermal model were calibrated to observed temperatures by optimizing basal heat-flow density and ignoring sediment heat production, the extrapolated present-day temperature of a deeply buried source rock would be overestimated.Radiogenic heat production within the sedimentary section of the Gulf of Mexico basin is a significant source of heat. Radiogenic heat should be included in thermal models of this basin (and perhaps other sedimentary basins). We calculate that radiogenic heat may contribute up to 26% of the overall surface heat-flow density for an area in south Texas. Based on measurements of the radioactive decay rate of ??-particles, potassium concentration, and bulk density, we

  20. Dietary fat affects heat production and other variables of equine performance, under hot and humid conditions.

    PubMed

    Kronfeld, D S

    1996-07-01

    Does dietary fat supplementation during conditioning improve athletic performance, especially in the heat? Fat adaptation has been used to increase energy density, decrease bowel bulk and faecal output and reduce health risks associated with hydrolysable carbohydrate overload. It may also reduce spontaneous activity and reactivity (excitability), increase fatty acid oxidation, reduce CO2 production and associated acidosis, enhance metabolic regulation of glycolysis, improve both aerobic and anaerobic performance and substantially reduce heat production. A thermochemical analysis of ATP generation showed the least heat release during the direct oxidation of long chain fatty acids, which have a 3% advantage over glucose and 20 to 30% over short chain fatty acids and amino acids. Indirect oxidation via storage as triglyceride increased heat loss during ATP generation by 3% for stearic acid, 65% for glucose and 174% for acetic acid. Meal feeding and nutrient storage, therefore, accentuates the advantage of dietary fat. A calorimetric model was based on initial estimates of net energy for competitive work (10.76 MJ for the Endurance Test of an Olympic level 3-day-event), other work (14.4 MJ/day) and maintenance (36 MJ), then applied estimates of efficiencies to derive associated heat productions for the utilisation of 3 diets, Diet A: hay (100), Diet B: hay and oats (50:50) and Diet C: hay, oats and vegetable oil (45:45:10), the difference between the last 2 diets representing fat adaptation. During a 90.5 min speed and stamina test, heat production was estimated as 37, 35.4 and 34.6 MJ for the 3 diets, respectively, an advantage 0.8 MJ less heat load for the fat adapted horse, which would reduce water needed for evaporation by 0.33 kg and reduce body temperature increase by about 0.07 degree C. Total estimated daily heat production was 105, 93 and 88 MJ for the 3 diets, respectively, suggesting a 5 MJ advantage for the fat adapted horse (Diet C vs. Diet B). Estimated

  1. Heat production in Littorina saxatilis Olivi and Littorina neritoides L. (gastropoda: Prosobranchia) during an experimental exposure to air

    NASA Astrophysics Data System (ADS)

    Kronberg, Inge

    1990-06-01

    The adaptation of littorinid molluscs to prolonged aerial exposure was investigated by the determination of heat production. Littorina saxatilis, inhabiting the upper eulittoral, reached a maximum metabolic activity during submersion (heat production: 3.26×10-3J s-1 (gadw)-1. On the first three days of desiccation, the heat production was continuously reduced to 40% of the submersed value. A prolonged aerial exposure was lethal for this species. In the supralittoral L. neritoides, three stages of energy metabolism could be observed: An intermediate heat production during submersion (1.97×10-3Js-1 (gadw)-1), an increased metabolism during the first hour of aerial exposure (heat production 204% of submersed value), and a minimal metabolism (39% of the submersed value and 19% of maximum value) during the following days and weeks of desiccation. Recovery depended on water salinity; L. saxatilis proved to be less euryhaline than L. neritoides. Thus, the metabolic adaptations correlate with the level of littoral habitat; inactivity combined with a drastically reduced energy consumption is a metabolically economic way to survive in periodically dry environments.

  2. Heat production and chemical change during isometric contraction of rat soleus muscle.

    PubMed Central

    Gower, D; Kretzschmar, K M

    1976-01-01

    1. Methods are described whereby the soleus muscle of the rat may be used for the investigation of initial processes in the absence of oxidative recovery. 2. The anaerobic conditions employed had no effect on the concentration of phosphocreatine in resting muscle or the mechanical response during contraction. 3. Muscles were stimulated tetanically for 10 s at 17-18 degrees C. Measurements were made of the heat production and metabolic changes that occurred during a 13 s period following the first stimulus. 4. There was no detectable change in the concentration of ATP. Neither was there detectable activity of adenylate kinase or adenylate deaminase. The changes in the concentration of glycolytic intermediaries were undetectable or very small. 5. The change in the concentration of phosphocreatine was large and amounted to -127 +/- 11-4 mumol/mmol Ct (mean and S.E. of the mean, negative sign indicates break-down, Ct = free creatine + phosphocreatine) which is equivalent to about -2-13 mumol/g wet weight of muscle. The heat production was 6549 +/- 408 mJ/mmol Ct (mean and S.E. of mean) which is equivalent to about 110 mJ/g. 6. About 30% of the observed energy output is unaccounted for by measured metabolic changes. 7. The ratio of heat production (corrected for small amounts of glycolytic activity) to phosphocreatine hydrolysis was -49-7 +/- 5-6 kJ/mol (mean and S.E. of mean), in agreement with previous results using comparable contractions of frog muscle, but different from the enthalpy change associated with phosphocreatine hydrolysis under in vivo conditions (-34 kJ/mol). 8. The results support the notion that the discrepancy between energy output and metabolism is an indication of an unidentified process of substantial energetic significance that is common to a number of species. PMID:978498

  3. New industrial heat pump applications to fructose production

    SciTech Connect

    Not Available

    1990-04-01

    An energy cost reduction study of the American Fructose Decatur,Inc. High Fructose Corn Syrup process has been completed. The objective was to find cost effective energy cost reduction projects and to develop a coherent strategy for realizing the savings. There are many possible options for reducing energy cost. To facilitate a fair comparison of the options, Pinch Technology was used to identify appropriate heat recovery, heat pumping and cogeneration options. Of particular interest were the opportunities for utilizing heat pumps, for energy cost reduction or other profit increasing uses. Therefore, where a heat pumping scheme was identified, its merits relative to other potential projects was carefully evaluated to ensure that the heat pump was technically and economically sound. It is felt that the results obtained in this study are applicable to other wet corn milling sites which include a refinery section, due to the similarity of processes throughout the industry. This study and others indicate that reductions in thermal energy consumption of 15--25% can be expected through increased heat recovery. Also, the use of MVR and thermocompression evaporators is appropriate and additional economically viable opportunities exist for using industrial heat pumps to increase even further the level of energy cost reduction achievable. 17 figs., 4 tabs.

  4. Heat stress and antioxidant enzyme activity in bubaline ( Bubalus bubalis) oocytes during in vitro maturation

    NASA Astrophysics Data System (ADS)

    Waiz, Syma Ashraf; Raies-ul-Haq, Mohammad; Dhanda, Suman; Kumar, Anil; Goud, T. Sridhar; Chauhan, M. S.; Upadhyay, R. C.

    2016-09-01

    In vitro environments like heat stress usually increase the production of reactive oxygen species in bubaline oocytes which have been implicated as one of the major causes for reduced developmental competence. Oocytes during meiotic maturation are sensitive to oxidative stress, and heat stress accelerates cellular metabolism, resulting in the higher production of free radicals. Therefore, the aim of present work was to assess the impact of heat stress during meiotic maturation on bubaline cumulus-oocyte complexes (COC), denuded oocytes (DO), and cumulus cell mass in terms of their oxidative status. Accordingly, for control group, COC were matured at 38.5 °C for complete 24 h of meiotic maturation and heat stress of 40.5 and 41.5 °C was applied to COC during the first 12 h of maturation and then moved to 38.5 °C for rest of the 12 h. In another group, COC after maturation were denuded from the surrounding cumulus cells by manual pipetting. Results indicated that the production of reactive oxygen species (ROS), lipid peroxides, and nitric oxide (NO) was significantly ( P < 0.05) higher in the oocytes subjected to heat stress (40.5 and 41.5 °C) during meiotic maturation compared to the oocytes matured under standard in vitro culture conditions (38.5 °C). Also, the antioxidant enzymatic activities of superoxide dismutase, catalase, glutathione peroxidase, and glutathione reductase were significantly ( P < 0.05) increased in all the treatment groups compared to the control group. Therefore, the present study clearly establishes that heat stress ensues oxidative stress in bubaline oocytes which triggers the induction of antioxidant enzymatic defense system for scavenging the ROS.

  5. Heat stress and antioxidant enzyme activity in bubaline (Bubalus bubalis) oocytes during in vitro maturation

    NASA Astrophysics Data System (ADS)

    Waiz, Syma Ashraf; Raies-ul-Haq, Mohammad; Dhanda, Suman; Kumar, Anil; Goud, T. Sridhar; Chauhan, M. S.; Upadhyay, R. C.

    2016-01-01

    In vitro environments like heat stress usually increase the production of reactive oxygen species in bubaline oocytes which have been implicated as one of the major causes for reduced developmental competence. Oocytes during meiotic maturation are sensitive to oxidative stress, and heat stress accelerates cellular metabolism, resulting in the higher production of free radicals. Therefore, the aim of present work was to assess the impact of heat stress during meiotic maturation on bubaline cumulus-oocyte complexes (COC), denuded oocytes (DO), and cumulus cell mass in terms of their oxidative status. Accordingly, for control group, COC were matured at 38.5 °C for complete 24 h of meiotic maturation and heat stress of 40.5 and 41.5 °C was applied to COC during the first 12 h of maturation and then moved to 38.5 °C for rest of the 12 h. In another group, COC after maturation were denuded from the surrounding cumulus cells by manual pipetting. Results indicated that the production of reactive oxygen species (ROS), lipid peroxides, and nitric oxide (NO) was significantly (P < 0.05) higher in the oocytes subjected to heat stress (40.5 and 41.5 °C) during meiotic maturation compared to the oocytes matured under standard in vitro culture conditions (38.5 °C). Also, the antioxidant enzymatic activities of superoxide dismutase, catalase, glutathione peroxidase, and glutathione reductase were significantly (P < 0.05) increased in all the treatment groups compared to the control group. Therefore, the present study clearly establishes that heat stress ensues oxidative stress in bubaline oocytes which triggers the induction of antioxidant enzymatic defense system for scavenging the ROS.

  6. Nanovalve-controlled cargo release activated by plasmonic heating.

    PubMed

    Croissant, Jonas; Zink, Jeffrey I

    2012-05-01

    The synthesis and operation of a light-operated nanovalve that controls the pore openings of mesoporous silica nanoparticles containing gold nanoparticle cores is described. The nanoparticles, consisting of 20 nm gold cores inside ~150 nm mesoporous silica spheres, were synthesized using a unique one-pot method. The nanovalves consist of cucurbit[6]uril rings encircling stalks that are attached to the ~2 nm pore openings. Plasmonic heating of the gold core raises the local temperature and decreases the ring-stalk binding constant, thereby unblocking the pore and releasing the cargo molecules that were preloaded inside. Bulk heating of the suspended particles to 60 °C is required to release the cargo, but no bulk temperature change was observed in the plasmonic heating release experiment. High-intensity irradiation caused thermal damage to the silica particles, but low-intensity illumination caused a local temperature increase sufficient to operate the valves without damaging the nanoparticle containers. These light-stimulated, thermally activated, mechanized nanoparticles represent a new system with potential utility for on-command drug release.

  7. Emission Measure Distribution and Heating of Two Active Region Cores

    NASA Technical Reports Server (NTRS)

    Tripathi, Durgesh; Klimchuk, James A.; Mason, Helen E.

    2011-01-01

    Using data from the Extreme-ultraviolet Imaging Spectrometer aboard Hinode, we have studied the coronal plasma in the core of two active regions. Concentrating on the area between opposite polarity moss, we found emission measure distributions having an approximate power-law form EM/T(exp 2.4) from log T = 5.55 up to a peak at log T = 6.57. The observations are explained extremely well by a simple nanoflare model. However, in the absence of additional constraints, the observations could possibly also be explained by steady heating.

  8. Effect of heating system using a geothermal heat pump on the production performance and housing environment of broiler chickens.

    PubMed

    Choi, H C; Salim, H M; Akter, N; Na, J C; Kang, H K; Kim, M J; Kim, D W; Bang, H T; Chae, H S; Suh, O S

    2012-02-01

    A geothermal heat pump (GHP) is a potential heat source for the economic heating of broiler houses with optimum production performance. An investigation was conducted to evaluate the effect of a heating system using a GHP on production performance and housing environment of broiler chickens. A comparative analysis was also performed between the GHP system and a conventional heating system that used diesel for fuel. In total, 34,000 one-day-old straight run broiler chicks were assigned to 2 broiler houses with 5 replicates in each (3,400 birds/replicate pen) for 35 d. Oxygen(,) CO(2), and NH(3) concentrations in the broiler house, energy consumption and cost of heating, and production performance of broilers were evaluated. Results showed that the final BW gain significantly (P < 0.05) increased when chicks were reared in the GHP broiler house compared with that of chicks reared in the conventional broiler house (1.73 vs. 1.62 kg/bird). The heating system did not affect the mortality of chicks during the first 4 wk of the experimental period, but the mortality markedly increased in the conventional broiler house during the last wk of the experiment. Oxygen content in the broiler house during the experimental period was not affected by the heating system, but the CO(2) and NH(3) contents significantly increased (P < 0.05) in the conventional broiler house compared with those in the GHP house. Fuel consumption was significantly reduced (P < 0.05) and electricity consumption significantly increased (P < 0.05) in the GHP house compared with the consumption in the conventional house during the experiment. The total energy cost of heating the GHP house was significantly lower (P < 0.05) compared with that of the conventional house. It is concluded that a GHP system could increase the production performance of broiler chicks due to increased inside air quality of the broiler house. The GHP system had lower CO(2) and NH(3) emissions with lower energy cost than the

  9. Effect of heating system using a geothermal heat pump on the production performance and housing environment of broiler chickens.

    PubMed

    Choi, H C; Salim, H M; Akter, N; Na, J C; Kang, H K; Kim, M J; Kim, D W; Bang, H T; Chae, H S; Suh, O S

    2012-02-01

    A geothermal heat pump (GHP) is a potential heat source for the economic heating of broiler houses with optimum production performance. An investigation was conducted to evaluate the effect of a heating system using a GHP on production performance and housing environment of broiler chickens. A comparative analysis was also performed between the GHP system and a conventional heating system that used diesel for fuel. In total, 34,000 one-day-old straight run broiler chicks were assigned to 2 broiler houses with 5 replicates in each (3,400 birds/replicate pen) for 35 d. Oxygen(,) CO(2), and NH(3) concentrations in the broiler house, energy consumption and cost of heating, and production performance of broilers were evaluated. Results showed that the final BW gain significantly (P < 0.05) increased when chicks were reared in the GHP broiler house compared with that of chicks reared in the conventional broiler house (1.73 vs. 1.62 kg/bird). The heating system did not affect the mortality of chicks during the first 4 wk of the experimental period, but the mortality markedly increased in the conventional broiler house during the last wk of the experiment. Oxygen content in the broiler house during the experimental period was not affected by the heating system, but the CO(2) and NH(3) contents significantly increased (P < 0.05) in the conventional broiler house compared with those in the GHP house. Fuel consumption was significantly reduced (P < 0.05) and electricity consumption significantly increased (P < 0.05) in the GHP house compared with the consumption in the conventional house during the experiment. The total energy cost of heating the GHP house was significantly lower (P < 0.05) compared with that of the conventional house. It is concluded that a GHP system could increase the production performance of broiler chicks due to increased inside air quality of the broiler house. The GHP system had lower CO(2) and NH(3) emissions with lower energy cost than the

  10. The equivalence of minimum entropy production and maximum thermal efficiency in endoreversible heat engines.

    PubMed

    Haseli, Y

    2016-05-01

    The objective of this study is to investigate the thermal efficiency and power production of typical models of endoreversible heat engines at the regime of minimum entropy generation rate. The study considers the Curzon-Ahlborn engine, the Novikov's engine, and the Carnot vapor cycle. The operational regimes at maximum thermal efficiency, maximum power output and minimum entropy production rate are compared for each of these engines. The results reveal that in an endoreversible heat engine, a reduction in entropy production corresponds to an increase in thermal efficiency. The three criteria of minimum entropy production, the maximum thermal efficiency, and the maximum power may become equivalent at the condition of fixed heat input.

  11. New industrial heat pump applications to cheese production

    SciTech Connect

    Not Available

    1990-04-01

    A energy cost reduction of the Sorrento Cheese Co. Inc. cheese/whey powder process has been completed. Of Particular interest were the opportunities for utilizing heat pumps for energy cost reduction or other profit improving uses. Pinch Technology was used to identify heat recovery, heat pumping, process modification and congeneration options. Pinch Technology provides a thermodynamically consistent base from which the relative merits of competing cost reduction options can be assessed. The study identified heat recovery opportunities which could save $198,000/yr at an over all payback of 26 months. Individual project paybacks range from 18 to 36 months. The use of heat pumps in the form of MVR and TVR evaporators is well established in the dairy industry. For this process, which already incorporates a TVR evaporator, no additional cost effective opportunities for utilizing heat pumps were identified. It is felt that the results obtained in this study are applicable to other cheese/whey powder manufacturing sits. This study, and others, indicate that reductions in thermal energy consumption of 10--15% can be expected. Also the use of MVR and TVR evaporators is appropriate. 10 figs., 1 tab.

  12. Selective disruption of high sensitivity heat activation but not capsaicin activation of TRPV1 channels by pore turret mutations.

    PubMed

    Cui, Yuanyuan; Yang, Fan; Cao, Xu; Yarov-Yarovoy, Vladimir; Wang, KeWei; Zheng, Jie

    2012-04-01

    The capsaicin receptor transient receptor potential vanilloid (TRPV)1 is a highly heat-sensitive ion channel. Although chemical activation and heat activation of TRPV1 elicit similar pungent, painful sensation, the molecular mechanism underlying synergistic activation remains mysterious. In particular, where the temperature sensor is located and whether heat and capsaicin share a common activation pathway are debated. To address these fundamental issues, we searched for channel mutations that selectively affected one form of activation. We found that deletion of the first 10 amino acids of the pore turret significantly reduced the heat response amplitude and shifted the heat activation threshold, whereas capsaicin activation remained unchanged. Removing larger portions of the turret disrupted channel function. Introducing an artificial sequence to replace the deleted region restored sensitive capsaicin activation in these nonfunctional channels. The heat activation, however, remained significantly impaired, with the current exhibiting diminishing heat sensitivity to a level indistinguishable from that of a voltage-gated potassium channel, Kv7.4. Our results demonstrate that heat and capsaicin activation of TRPV1 are structurally and mechanistically distinct processes, and the pore turret is an indispensible channel structure involved in the heat activation process but is not part of the capsaicin activation pathway. Synergistic effect of heat and capsaicin on TRPV1 activation may originate from convergence of the two pathways on a common activation gate.

  13. r-PROCESS LANTHANIDE PRODUCTION AND HEATING RATES IN KILONOVAE

    SciTech Connect

    Lippuner, Jonas; Roberts, Luke F.

    2015-12-20

    r-process nucleosynthesis in material ejected during neutron star mergers may lead to radioactively powered transients called kilonovae. The timescale and peak luminosity of these transients depend on the composition of the ejecta, which determines the local heating rate from nuclear decays and the opacity. Kasen et al. and Tanaka and Hotokezaka pointed out that lanthanides can drastically increase the opacity in these outflows. We use the new general-purpose nuclear reaction network SkyNet to carry out a parameter study of r-process nucleosynthesis for a range of initial electron fractions Y{sub e}, initial specific entropies s, and expansion timescales τ. We find that the ejecta is lanthanide-free for Y{sub e} ≳ 0.22−0.30, depending on s and τ. The heating rate is insensitive to s and τ, but certain, larger values of Y{sub e} lead to reduced heating rates, due to individual nuclides dominating the heating. We calculate approximate light curves with a simplified gray radiative transport scheme. The light curves peak at about a day (week) in the lanthanide-free (-rich) cases. The heating rate does not change much as the ejecta becomes lanthanide-free with increasing Y{sub e}, but the light-curve peak becomes about an order of magnitude brighter because it peaks much earlier when the heating rate is larger. We also provide parametric fits for the heating rates between 0.1 and 100 days, and we provide a simple fit in Y{sub e}, s, and τ to estimate whether or not the ejecta is lanthanide-rich.

  14. Carbonaceous material for production of hydrogen from low heating value fuel gases

    DOEpatents

    Koutsoukos, Elias P.

    1989-01-01

    A process for the catalytic production of hydrogen, from a wide variety of low heating value fuel gases containing carbon monoxide, comprises circulating a carbonaceous material between two reactors--a carbon deposition reactor and a steaming reactor. In the carbon deposition reactor, carbon monoxide is removed from a fuel gas and is deposited on the carbonaceous material as an active carbon. In the steaming reactor, the reactive carbon reacts with steam to give hydrogen and carbon dioxide. The carbonaceous material contains a metal component comprising from about 75% to about 95% cobalt, from about 5% to about 15% iron, and up to about 10% chromium, and is effective in suppressing the production of methane in the steaming reactor.

  15. Suomi NPP VIIRS active fire product status

    NASA Astrophysics Data System (ADS)

    Ellicott, E. A.; Csiszar, I. A.; Schroeder, W.; Giglio, L.; Wind, B.; Justice, C. O.

    2012-12-01

    We provide an overview of the evaluation and development of the Active Fires product derived from the Visible Infrared Imager Radiometer Suite (VIIRS) sensor on the Suomi National Polar-orbiting Partnership (SNPP) satellite during the first year of on-orbit data. Results from the initial evaluation of the standard SNPP Active Fires product, generated by the SNPP Interface Data Processing System (IDPS), supported the stabilization of the VIIRS Sensor Data Record (SDR) product. This activity focused in particular on the processing of the dual-gain 4 micron VIIRS M13 radiometric measurements into 750m aggregated data, which are fundamental for active fire detection. Following the VIIRS SDR product's Beta maturity status in April 2012, correlative analysis between VIIRS and near-simultaneous fire detections from the Moderate Resolution Imaging Spectroradiometer (MODIS) on the NASA Earth Observing System Aqua satellite confirmed the expected relative detection rates driven primarily by sensor differences. The VIIRS Active Fires Product Development and Validation Team also developed a science code that is based on the latest MODIS Collection 6 algorithm and provides a full spatially explicit fire mask to replace the sparse array output of fire locations from a MODIS Collection 4 equivalent algorithm in the current IDPS product. The Algorithm Development Library (ADL) was used to support the planning for the transition of the science code into IDPS operations in the future. Product evaluation and user outreach was facilitated by a product website that provided end user access to fire data in user-friendly format over North America as well as examples of VIIRS-MODIS comparisons. The VIIRS fire team also developed an experimental product based on 375m VIIRS Imagery band measurements and provided high quality imagery of major fire events in US. By August 2012 the IDPS product achieved Beta maturity, with some known and documented shortfalls related to the processing of

  16. Cardiac activation heat remains inversely dependent on temperature over the range 27-37°C.

    PubMed

    Johnston, Callum M; Han, June-Chiew; Loiselle, Denis S; Nielsen, Poul M F; Taberner, Andrew J

    2016-06-01

    The relation between heat output and stress production (force per cross-sectional area) of isolated cardiac tissue is a key metric that provides insight into muscle energetic performance. The heat intercept of the relation, termed "activation heat," reflects the metabolic cost of restoring transmembrane gradients of Na(+) and K(+) following electrical excitation, and myoplasmic Ca(2+) concentration following its release from the sarcoplasmic reticulum. At subphysiological temperatures, activation heat is inversely dependent on temperature. Thus one may presume that activation heat would decrease even further at body temperature. However, this assumption is prima facie inconsistent with a study, using intact hearts, which revealed no apparent change in the combination of activation and basal metabolism between 27 and 37°C. It is thus desired to directly determine the change in activation heat between 27 and 37°C. In this study, we use our recently constructed high-thermal resolution muscle calorimeter to determine the first heat-stress relation of isolated cardiac muscle at 37°C. We compare the relation at 37°C to that at 27°C to examine whether the inverse temperature dependence of activation heat, observed under hypothermic conditions, prevails at body temperature. Our results show that activation heat was reduced (from 3.5 ± 0.3 to 2.3 ± 0.3 kJ/m(3)) at the higher temperature. This leads us to conclude that activation metabolism continues to decline as temperature is increased from hypothermia to normothermia and allows us to comment on results obtained from the intact heart by previous investigators.

  17. Cardiac activation heat remains inversely dependent on temperature over the range 27-37°C.

    PubMed

    Johnston, Callum M; Han, June-Chiew; Loiselle, Denis S; Nielsen, Poul M F; Taberner, Andrew J

    2016-06-01

    The relation between heat output and stress production (force per cross-sectional area) of isolated cardiac tissue is a key metric that provides insight into muscle energetic performance. The heat intercept of the relation, termed "activation heat," reflects the metabolic cost of restoring transmembrane gradients of Na(+) and K(+) following electrical excitation, and myoplasmic Ca(2+) concentration following its release from the sarcoplasmic reticulum. At subphysiological temperatures, activation heat is inversely dependent on temperature. Thus one may presume that activation heat would decrease even further at body temperature. However, this assumption is prima facie inconsistent with a study, using intact hearts, which revealed no apparent change in the combination of activation and basal metabolism between 27 and 37°C. It is thus desired to directly determine the change in activation heat between 27 and 37°C. In this study, we use our recently constructed high-thermal resolution muscle calorimeter to determine the first heat-stress relation of isolated cardiac muscle at 37°C. We compare the relation at 37°C to that at 27°C to examine whether the inverse temperature dependence of activation heat, observed under hypothermic conditions, prevails at body temperature. Our results show that activation heat was reduced (from 3.5 ± 0.3 to 2.3 ± 0.3 kJ/m(3)) at the higher temperature. This leads us to conclude that activation metabolism continues to decline as temperature is increased from hypothermia to normothermia and allows us to comment on results obtained from the intact heart by previous investigators. PMID:27016583

  18. OBSERVING EPISODIC CORONAL HEATING EVENTS ROOTED IN CHROMOSPHERIC ACTIVITY

    SciTech Connect

    McIntosh, Scott W.; De Pontieu, Bart E-mail: bdp@lmsal.co

    2009-11-20

    We present the results of a multi-wavelength study of episodic plasma injection into the corona of active region (AR) 10942. We exploit long-exposure images of the Hinode and Transition Region and Coronal Explorer spacecraft to study the properties of faint, episodic, 'blobs' of plasma that are propelled upward along coronal loops that are rooted in the AR plage. We find that the source location and characteristic velocities of these episodic upflow events match those expected from recent spectroscopic observations of faint coronal upflows that are associated with upper chromospheric activity, in the form of highly dynamic spicules. The analysis presented ties together observations from coronal and chromospheric spectrographs and imagers, providing more evidence of the connection of discrete coronal mass heating and injection events with their source, dynamic spicules, in the chromosphere.

  19. Geoneutrinos and Heat Production in the Earth: Constraints and Implications

    ScienceCinema

    McDonough, Bill [University of Maryland, College Park, Maryland, United States

    2016-07-12

    Recent results from antineutrino (geoneutrino) studies at KamLAND are coincident with geochemical models of Th and U in the Earth.  KamLAND and Borexino detectors are on line, thus uncertainties in counting statistics will be reduced as data are accumulated.  The SNO+ detector, situated in the middle of the North American plate will come on line in ~3 yrs and will be best suited to yield a precise estimate of the continental contribution to the Earth’s Th & U budget.  The distribution of heat producing elements in the Earth drives convection and plate tectonics.  Geochemical models posit that ~40% of the heat producing elements are in the continental crust, with the remainder in the mantle.  Although models of core formation allow for the incorporation of heat producing elements, the core contribution of radiogenic heating is considered to be negligible.  Most parameterized convection models for the Earth require significant amounts of radiogenic heating of the Earth, a factor of two greater than geochemical models predict.  The initial KamLAND results challenge these geophysical models and support geochemical models calling for a significant contribution from secular cooling of the mantle.

  20. Geoneutrinos and Heat Production in the Earth: Constraints and Implications

    SciTech Connect

    McConough, Bill

    2008-07-02

    Recent results from antineutrino (geoneutrino) studies at KamLAND are coincident with geochemical models of Th and U in the Earth. KamLAND and Borexino detectors are on line, thus uncertainties in counting statistics will be reduced as data are accumulated. The SNO+ detector, situated in the middle of the North American plate will come on line in {approx}3 yrs and will be best suited to yield a precise estimate of the continental contribution to the Earth's Th & U budget. The distribution of heat producing elements in the Earth drives convection and plate tectonics. Geochemical models posit that {approx}40% of the heat producing elements are in the continental crust, with the remainder in the mantle. Although models of core formation allow for the incorporation of heat producing elements, the core contribution of radiogenic heating is considered to be negligible. Most parameterized convection models for the Earth require significant amounts of radiogenic heating of the Earth, a factor of two greater than geochemical models predict. The initial KamLAND results challenge these geophysical models and support geochemical models calling for a significant contribution from secular cooling of the mantle.

  1. Geoneutrinos and Heat Production in the Earth: Constraints and Implications

    SciTech Connect

    McDonough, Bill

    2008-07-02

    Recent results from antineutrino (geoneutrino) studies at KamLAND are coincident with geochemical models of Th and U in the Earth.  KamLAND and Borexino detectors are on line, thus uncertainties in counting statistics will be reduced as data are accumulated.  The SNO+ detector, situated in the middle of the North American plate will come on line in ~3 yrs and will be best suited to yield a precise estimate of the continental contribution to the Earth’s Th & U budget.  The distribution of heat producing elements in the Earth drives convection and plate tectonics.  Geochemical models posit that ~40% of the heat producing elements are in the continental crust, with the remainder in the mantle.  Although models of core formation allow for the incorporation of heat producing elements, the core contribution of radiogenic heating is considered to be negligible.  Most parameterized convection models for the Earth require significant amounts of radiogenic heating of the Earth, a factor of two greater than geochemical models predict.  The initial KamLAND results challenge these geophysical models and support geochemical models calling for a significant contribution from secular cooling of the mantle.

  2. Anti-cancer activities of pH- or heat-modified pectin

    PubMed Central

    Leclere, Lionel; Cutsem, Pierre Van; Michiels, Carine

    2013-01-01

    Despite enormous efforts that have been made in the search for novel drugs and treatments, cancer continues to be a major public health problem. Moreover, the emergence of resistance to cancer chemotherapy often prevents complete remission. Researchers have thus turned to natural products mainly from plant origin to circumvent resistance. Pectin and pH- or heat-modified pectin have demonstrated chemopreventive and antitumoral activities against some aggressive and recurrent cancers. The focus of this review is to describe how pectin and modified pectin display these activities and what are the possible underlying mechanisms. The failure of conventional chemotherapy to reduce mortality as well as serious side effects make natural products, such as pectin-derived products, ideal candidates for exerting synergism in combination with conventional anticancer drugs. PMID:24115933

  3. Heating and ultraviolet light activate anti-stress gene functions in humans.

    PubMed

    Semenkov, Victor F; Michalski, Anatoli I; Sapozhnikov, Alexander M

    2015-01-01

    Different environmental factors (i.e., toxins, heavy metals, ultraviolet (UV) rays, and X-radiation) cause damage to DNA, cell membranes and other organelles and induce oxidative stress, which results in the excessive production of reactive oxygen species (ROS) by phagocytes. All types of cell stress are accompanied by the activation of anti-stress genes that can suppress ROS synthesis. We hypothesized that different environmental factors would affect organisms through the activation of anti-stress genes by autologous serum (AS) proteins, followed by the synthesis of molecules that increase cell resistance to oxidative stress. The goal of this work was to study the influence of AS on ROS production by peripheral blood neutrophils isolated from donors in different age groups. Neutrophils were isolated from 59 donors (38-94 years old). AS was heated at 100°C for 30 s. or irradiated by UV light at 200-280 nm and 8 W for 10 min. Neutrophils were exposed to heat shock at 42°C for 1 min. (short-term heating stress) or 43°C for 10 min., followed by the determination of the chemiluminescence reaction induced by zymosan. AS can increase or decrease ROS production by neutrophils depending on the structure of the proteins in the serum; these structures can be changed by heating or UV treatment and the temperature of their interaction (4 or 37°C). We propose that the effect of environmental factors on AS proteins can cause an adverse increase in oxidative stress levels due to the functional reduction of anti-stress genes. We found a negative correlation between the quantity of intracellular Hsp70 and levels of intracellular ROS production following 10 min of heat shock at 43°C. Short-term heating stress (1 min) at 42°C was followed by a prominent reduction in ROS production. This effect may be a result of the impact of the hormone adrenaline on the functions of anti-stress genes. Indeed, the same effect was observed after treatment of the neutrophils with adrenaline at

  4. Heat stress control in the TMI-2 (Three Mile Island Unit 2) defueling and decontamination activities

    SciTech Connect

    Schork, J.S.; Parfitt, B.A.

    1988-01-01

    During the initial stages of the Three Mile Island Unit 2 (TMI-2) defueling and decontamination activities for the reactor building, it was realized that the high levels of loose radioactive contamination would require the use of extensive protective clothing by entry personnel. While there was no doubt that layered protective clothing protects workers from becoming contaminated, it was recognized that these same layers of clothing would impose a very significant heat stress burden. To prevent the potentially serious consequences of a severe reaction to heat stress by workers in the hostile environment of the TMI-2 reactor building and yet maintain the reasonable work productivity necessary to perform the recovery adequately, an effective program of controlling worker exposure to heat stress had to be developed. Body-cooling devices produce a flow of cool air, which is introduced close to the skin to remove body heat through convection and increased sweat evaporation. The cooling effect produced by the Vortex tube successfully protected the workers from heat stress, however, there were several logistical and operational problems that hindered extensive use of these devices. The last type of cooling garment examined was the frozen water garment (FWG) developed by Elizier Kamon at the Pennsylvania State University as part of an Electric Power Research Institute research grant. Personal protection, i.e., body cooling, engineering controls, and administrative controls, have been implemented successfully.

  5. Fasting heat production and metabolic BW in group-housed broilers.

    PubMed

    Noblet, J; Dubois, S; Lasnier, J; Warpechowski, M; Dimon, P; Carré, B; van Milgen, J; Labussière, E

    2015-07-01

    Fasting heat production (FHP) is used for characterizing the basal metabolic rate of animals and the corresponding maintenance energy requirements and in the calculation of net energy value of feeds. In broilers, the most recent FHP estimates were obtained in the 1980s in slow-growing and fatter birds than nowadays. The FHP values (n=73; six experiments) measured in 3 to 6-week-old modern lines of broilers weighing 0.6 to 2.8 kg and growing at 80 to 100 g/day were used to update these literature values. Each measurement was obtained in a group of fasting broilers (5 to 14 birds) kept in a respiration chamber for at least 24 h. The FHP estimate corresponds to the asymptotic heat production corrected for zero physical activity obtained by modeling the decrease in heat production during the fasting day. The compilation of these data indicates that FHP was linearly related to the BW(0.70) (in kg), which can be considered as the metabolic BW of modern broilers. The 0.70 exponent differs from the conventional value of 0.75 used for mature animals. The FHP per kg of BW(0.70) ranged between 410 and 460 kJ/day according to the experiment (P<0.01). An experiment conducted with a shorter duration of fasting (16 h) indicated that FHP values are higher than those obtained over at least 24 h of fasting. Our values are similar to those obtained previously on fatter and slow-growing birds, even though the comparison is difficult since measurement conditions and methodologies have changed during the last 30 years. The FHP values obtained in our trials represent a basis for energy nutrition of modern broilers.

  6. Influence of arbuscular mycorrhiza on the growth and antioxidative activity in cyclamen under heat stress.

    PubMed

    Maya, Moslama Aktar; Matsubara, Yoh-ichi

    2013-07-01

    The influence of the arbuscular mycorrhizal (AM) fungus, Glomus fasciculatum, on the growth, heat stress responses and the antioxidative activity in cyclamen (Cyclamen persicum Mill.) plants was studied. Cyclamen plants (inoculated or not with the AM fungus) were placed in a commercial potting media at 17-20 °C for 12 weeks in a greenhouse and subsequently subjected to two temperature conditions in a growth chamber. Initially, plants were grown at 20 °C for 4 weeks as a no heat stress (HS-) condition, followed by 30 °C for another 4 weeks as a heat stress (HS+) condition. Different morphological and physiological growth parameters were compared between G. fasciculatum-inoculated and noninoculated plants. The mycorrhizal symbiosis markedly enhanced biomass production and HS + responses in plants compared to that in the controls. A severe rate of leaf browning (80-100%) was observed in control plants, whereas the mycorrhizal plants showed a minimum rate of leaf browning under HS + conditions. The mycorrhizal plants showed an increase activity of antioxidative enzymes such as superoxide dismutase and ascorbate peroxidase, as well as an increase in ascorbic acid and polyphenol contents. The 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity also showed a greater response in mycorrhizal plants than in the control plants under each temperature condition. The results indicate that in cyclamen plants, AM fungal colonisation alleviated heat stress damage through an increased antioxidative activity and that the mycorrhizal symbiosis strongly enhanced temperature stress tolerance which promoted plant growth and increased the host biomass under heat stress.

  7. Biodiesel production from waste frying oil using waste animal bone and solar heat.

    PubMed

    Corro, Grisel; Sánchez, Nallely; Pal, Umapada; Bañuelos, Fortino

    2016-01-01

    A two-step catalytic process for the production of biodiesel from waste frying oil (WFO) at low cost, utilizing waste animal-bone as catalyst and solar radiation as heat source is reported in this work. In the first step, the free fatty acids (FFA) in WFO were esterified with methanol by a catalytic process using calcined waste animal-bone as catalyst, which remains active even after 10 esterification runs. The trans-esterification step was catalyzed by NaOH through thermal activation process. Produced biodiesel fulfills all the international requirements for its utilization as a fuel. A probable reaction mechanism for the esterification process is proposed considering the presence of hydroxyapatite at the surface of calcined animal bones.

  8. Salicylic acid alleviates adverse effects of heat stress on photosynthesis through changes in proline production and ethylene formation

    PubMed Central

    Khan, M Iqbal R; Iqbal, Noushina; Masood, Asim; Per, Tasir S; Khan, Nafees A

    2013-01-01

    We investigated the potential of salicylic acid (SA) in alleviating the adverse effects of heat stress on photosynthesis in wheat (Triticum aestivum L.) cv WH 711. Activity of ribulose 1,5-bisphosphate carboxylase (Rubisco), photosynthetic-nitrogen use efficiency (NUE), and net photosynthesis decreased in plants subjected to heat stress (40°C for 6 h), but proline metabolism increased. SA treatment (0.5 mM) alleviated heat stress by increasing proline production through the increase in γ-glutamyl kinase (GK) and decrease in proline oxidase (PROX) activity, resulting in promotion of osmotic potential and water potential necessary for maintaining photosynthetic activity. Together with this, SA treatment restricted the ethylene formation in heat-stressed plants to optimal range by inhibiting activity of 1-aminocyclopropane carboxylic acid (ACC) synthase (ACS). This resulted in improved proline metabolism, N assimilation and photosynthesis. The results suggest that SA interacts with proline metabolism and ethylene formation to alleviate the adverse effects of heat stress on photosynthesis in wheat. PMID:24022274

  9. Salicylic acid alleviates adverse effects of heat stress on photosynthesis through changes in proline production and ethylene formation.

    PubMed

    Khan, M Iqbal R; Iqbal, Noushina; Masood, Asim; Per, Tasir S; Khan, Nafees A

    2013-11-01

    We investigated the potential of salicylic acid (SA) in alleviating the adverse effects of heat stress on photosynthesis in wheat (Triticum aestivum L.) cv WH 711. Activity of ribulose 1,5-bisphosphate carboxylase (Rubisco), photosynthetic-nitrogen use efficiency (NUE), and net photosynthesis decreased in plants subjected to heat stress (40 °C for 6 h), but proline metabolism increased. SA treatment (0.5 mM) alleviated heat stress by increasing proline production through the increase in γ-glutamyl kinase (GK) and decrease in proline oxidase (PROX) activity, resulting in promotion of osmotic potential and water potential necessary for maintaining photosynthetic activity. Together with this, SA treatment restricted the ethylene formation in heat-stressed plants to optimal range by inhibiting activity of 1-aminocyclopropane carboxylic acid (ACC) synthase (ACS). This resulted in improved proline metabolism, N assimilation and photosynthesis. The results suggest that SA interacts with proline metabolism and ethylene formation to alleviate the adverse effects of heat stress on photosynthesis in wheat.

  10. Heat and moisture production of layers in constant and dynamic environments

    SciTech Connect

    Dubensky, H.J.; Puri, V.M.; Manbeck, H.B.

    1986-01-01

    Heat and moisture production of layers under constant and cyclic environments were measured and compared to published values. These data were obtained from two environmental chambers each with a capacity for 48 caged birds. Sensible heat for the constant thermal environment compared favorably with published values. Latent heat differed from published values, this difference was attributed to evaporation from fecal matter. Preliminary results from cyclic environments are presented.

  11. Ion Heating Anisotropy during Dynamo Activity in the MST RFP

    NASA Astrophysics Data System (ADS)

    den Hartog, D. J.; Chapman, J. T.; Craig, D.; Fiksel, G.; Fontana, P. W.

    1999-11-01

    MHD dynamo activity is large in the MST Reversed-Field Pinch during sawtooth crashes, and small otherwise. During a sawtooth crash, ion temperature increases rapidly to a level several times as high as the temperature between sawteeth, which itself can be larger than the electron temperature. Several theories have been developed to explain this ion heating, some indicating a possible asymmetry in perpendicular to parallel heating [C. G. Gimblett, Europhys. Lett. 11, 541 (1990); Z. Yoshida, Nucl. Fusion 31, 386 (1991); N. Mattor, P. W. Terry, and S. C. Prager, Comments Plasma Phys. Controlled Fusion 15, 65 (1992)]. In standard MST discharges, impurity ion temperature measured perpendicular to the magnetic field (T_⊥) is higher than impurity ion temperature parallel to the magnetic field (T_allel) during a sawtooth crash. Throughout the rest of the sawtooth cycle, T_⊥ <= T_allel. This is in contrast to results obtained on the EXTRAP-T2 RFP which showed T_⊥ < T_allel throughout the discharge [K. Sasaki et al., Plasma Phys. Control. Fusion 39, 333 (1997)

  12. Is active sweating during heat acclimation required for improvements in peripheral sweat gland function?

    PubMed Central

    Numan, Travis R.; Claros, Ryan M.; Brodine, Stephanie K.; Kolkhorst, Fred W.

    2009-01-01

    We investigated whether the eccrine sweat glands must actively produce sweat during heat acclimation if they are to adapt and increase their capacity to sweat. Eight volunteers received intradermal injections of BOTOX, to prevent neural stimulation and sweat production of the sweat glands during heat acclimation, and saline injections as a control in the contralateral forearm. Subjects performed 90 min of moderate-intensity exercise in the heat (35°C, 40% relative humidity) on 10 consecutive days. Heat acclimation decreased end-exercise heart rate (156 ± 22 vs. 138 ± 17 beats/min; P = 0.0001) and rectal temperature (38.2 ± 0.3 vs. 37.9 ± 0.3°C; P = 0.0003) and increased whole body sweat rate (0.70 ± 0.29 vs. 1.06 ± 0.50 l/h; P = 0.030). During heat acclimation, there was no measurable sweating in the BOTOX-treated forearm, but the control forearm sweat rate during exercise increased 40% over the 10 days (P = 0.040). Peripheral sweat gland function was assessed using pilocarpine iontophoresis before and after heat acclimation. Before heat acclimation, the pilocarpine-induced sweat rate of the control and BOTOX-injected forearms did not differ (0.65 ± 0.20 vs. 0.66 ± 0.22 mg·cm−2·min−1). However, following heat acclimation, the pilocarpine-induced sweat rate in the control arm increased 18% to 0.77 ± 0.21 mg·cm−2·min−1 (P = 0.021) but decreased 52% to 0.32 ± 0.18 mg·cm−2·min−1 (P < 0.001) in the BOTOX-treated arm. Using complete chemodenervation of the sweat glands, coupled with direct cholinergic stimulation via pilocarpine iontophoresis, we demonstrated that sweat glands must be active during heat acclimation if they are to adapt and increase their capacity to sweat. PMID:19657101

  13. Adverse impact of heat stress on embryo production: causes and strategies for mitigation.

    PubMed

    Hansen, P J; Drost, M; Rivera, R M; Paula-Lopes, F F; al-Katanani, Y M; Krininger, C E; Chase, C C

    2001-01-01

    The production of embryos by superovulation is often reduced in periods of heat stress. The associated reduction in the number of transferable embryos is due to reduced superovulatory response, lower fertilization rate, and reduced embryo quality. There are also reports that success of in vitro fertilization procedures is reduced during warm periods of the year. Heat stress can compromise the reproductive events required for embryo production by decreasing expression of estrus behavior, altering follicular development, compromising oocyte competence, and inhibiting embryonic development. While preventing effects of heat stress can be difficult, several strategies exist to improve embryo production during heat stress. Among these strategies are changing animal housing to reduce the magnitude of heat stress, utilization of cows with increased resistance to heat stress (i.e., cows with lower milk yield or from thermally-adapted breeds), and manipulation of physiological and cellular function to overcome deleterious consequences of heat stress. Effects of heat stress on estrus behavior can be mitigated by use of estrus detection aids or utilization of ovulation synchronization treatments to allow timed embryo transfer. There is some evidence that embryonic survival can be improved by antioxidant administration and that pharmacological treatments can be developed that reduce the degree of hyperthermia experienced by cows exposed to heat stress.

  14. Magnetic Influences on Turbulent Heating and Jet Production in Coronal Holes

    NASA Astrophysics Data System (ADS)

    Woolsey, L. N.; Cranmer, S. R.

    2015-12-01

    The heating of the solar wind from open-field regions in the corona is the subject of an ongoing body of work in the solar physics community. We present recent progress to understand the role of Alfvén-wave-driven turbulence in flux tubes open to the heliosphere. Our models use three-dimensional, time-dependent forms of the reduced magnetohydrodynamics equations to find the resulting properties of the solar wind. We use the BRAID model (van Ballegooijen et al., 2011) on open flux tubes that epitomize the most common magnetic structures in the corona: a polar coronal hole, an open flux tube on the boundary of an equatorial streamer, and one that neighbors a strong active region. Our results agree with prior work using the time-steady, one-dimensional ZEPHYR model (Cranmer et al., 2007; Woolsey and Cranmer, 2014). In addition, the time dependence in BRAID lets us explore the bursty, nanoflare-like nature of the heating in these flux tubes. We find that the transient heating can be captured into separate events with an average energy of 1022 erg, with a maximum energy of 1025 erg. The bursty heating lead us to pursue a better understanding of the physical processes responsible for the network jets seen in IRIS data (see e.g. Tian et al., 2014). We search for correlations between the supergranular magnetic field properties—using the Helioseismic and Magnetic Imager aboard SDO—and jet productivity to make better estimates of the mass and energy budget of these small-scale features and to find evidence of the mechanisms responsible for the network jets.

  15. Performance evaluation of adding ethanol production into an existing combined heat and power plant.

    PubMed

    Starfelt, F; Thorin, E; Dotzauer, E; Yan, J

    2010-01-01

    In this paper, the configuration and performance of a polygeneration system are studied by modelling the integration of a lignocellulosic wood-to-ethanol process with an existing combined heat and power (CHP) plant. Data from actual plants are applied to validate the simulation models. The integrated polygeneration system reaches a total efficiency of 50%, meeting the heating load in the district heating system. Excess heat from the ethanol production plant supplies 7.9 MW to the district heating system, accounting for 17.5% of the heat supply at full heating load. The simulation results show that the production of ethanol from woody biomass is more efficient when integrated with a CHP plant compared to a stand-alone production plant. The total biomass consumption is reduced by 13.9% while producing the same amounts of heat, electricity and ethanol fuel as in the stand-alone configurations. The results showed that another feature of the integrated polygeneration system is the longer annual operating period compared to existing cogeneration. Thus, the renewable electricity production is increased by 2.7% per year.

  16. Virtual Grower: Software to Calculate Heating Costs of Greenhouse Production in the US

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Greenhouses are used in many climates either for season extension or year-round production, and can be expensive to heat. Greenhouse users and growers are often faced with management decisions that rely on an understanding of how temperature settings, heating systems, fuel types, and construction d...

  17. Performance evaluation of adding ethanol production into an existing combined heat and power plant.

    PubMed

    Starfelt, F; Thorin, E; Dotzauer, E; Yan, J

    2010-01-01

    In this paper, the configuration and performance of a polygeneration system are studied by modelling the integration of a lignocellulosic wood-to-ethanol process with an existing combined heat and power (CHP) plant. Data from actual plants are applied to validate the simulation models. The integrated polygeneration system reaches a total efficiency of 50%, meeting the heating load in the district heating system. Excess heat from the ethanol production plant supplies 7.9 MW to the district heating system, accounting for 17.5% of the heat supply at full heating load. The simulation results show that the production of ethanol from woody biomass is more efficient when integrated with a CHP plant compared to a stand-alone production plant. The total biomass consumption is reduced by 13.9% while producing the same amounts of heat, electricity and ethanol fuel as in the stand-alone configurations. The results showed that another feature of the integrated polygeneration system is the longer annual operating period compared to existing cogeneration. Thus, the renewable electricity production is increased by 2.7% per year. PMID:19758800

  18. Crustal Heat Production and the Thermal Evolution of Mars. Revision

    NASA Technical Reports Server (NTRS)

    McLennan, Scott M.

    2001-01-01

    The chemical compositions of soils and rocks from the Pathfinder site and Phobos-2 orbital gamma-ray spectroscopy indicate that the Martian crust has a bulk composition equivalent to large-ion lithophile (LIL) and heat-producing element (HPE) enriched basalt, with a potassium content of about 0.5%. A variety of radiogenic isotopic data also suggest that separation of LIL-enriched crustal and depleted mantle reservoirs took place very early in Martian history (greater than 4.0 Ga). Accordingly, if the enriched Martian crust is greater than 30km thick it is likely that a large fraction (up to at least 50%) of the heat-producing elements in Mars was transferred into the crust very early in the planet's history. This would greatly diminish the possibility of early widespread melting of the Martian mantle.

  19. Temperature and heat production patterns inside organism clusters

    NASA Astrophysics Data System (ADS)

    Kyaw Tha Paw, U.

    1988-06-01

    Clustering of organisms under cold air temperature conditions is modelled with a finite-difference method. Metabolic functions of temperature are used to simulate completely ectothermic, completely endothermic, and other organisms. To adequately match real conditions, the core temperature is kept constant at a high level, while the periphery of the organism cluster is assigned a lower temperature representing the cold conditions under which clustering is observed for organisms. The numerical model reasonably predicts the observed temperature distribution in honeybee clusters. The results do not support suggestions that organisms could overheat in the core of a cluster if they do not use thermoregulatory mechanisms to cool down. Endothermic organisms are not as efficient as ectothermic ones in heating a cluster core temperature to a given level. The general ectothermic metabolic rate function exhibited one of the highest efficiencies for heating the cluster.

  20. Thermal design for areas of interference heating on actively cooled hypersonic aircraft

    NASA Technical Reports Server (NTRS)

    Herring, R. L.; Stone, J. E.

    1978-01-01

    Numerous actively cooled panel design alternatives for application in regions on high speed aircraft that are subject to interference heating effects were studied. Candidate design concepts were evaluated using mass, producibility, reliability and inspectability/maintainability as figures of merit. Three design approaches were identified as superior within certain regimes of the matrix of design heating conditions considered. Only minor modifications to basic actively cooled panel design are required to withstand minor interference heating effects. Designs incorporating internally finned coolant tubes to augment heat transfer are recommended for moderate design heating conditions. At severe heating conditions, an insulated panel concept is required.

  1. Adjustments in metabolic heat production by squirrel monkeys exposed to microwaves

    SciTech Connect

    Adair, E.R.; Adams, B.W.

    1982-04-01

    The basic fact that microwave exposure can lower metabolic heat production has been previously demonstrated for the mouse by Ho and Edwards (1977) and for the rat by Phillips et al. (1975). The general conclusion drawn from both studies was that the metabolic reduction produced by microwave exposure was dose dependent. The present study extends the investigation into the effects of microwave exposure on metabolic heat production to a primate, the squirrel monkey. When squirrel monkeys are restrained in cool environments, body temperature is regulated by an increase in metabolic heat production. The results of the current study demonstrate that either brief or prolonged whole-body exposure to a microwave field will cause a reduction of this elevated heat production by an amount directly related to the microwave energy absorbed.

  2. Energy-Storage Modules for Active Solar Heating and Cooling

    NASA Technical Reports Server (NTRS)

    Parker, J. C.

    1982-01-01

    34 page report describes a melting salt hydrate that stores 12 times as much heat as rocks and other heavy materials. Energy is stored mostly as latent heat; that is, heat that can be stored and recovered without any significant change in temperature. Report also describes development, evaluation and testing of permanently sealed modules containing salt hydrate mixture.

  3. Fission Product Decay Heat Calculations for Neutron Fission of 232Th

    NASA Astrophysics Data System (ADS)

    Son, P. N.; Hai, N. X.

    2016-06-01

    Precise information on the decay heat from fission products following times after a fission reaction is necessary for safety designs and operations of nuclear-power reactors, fuel storage, transport flasks, and for spent fuel management and processing. In this study, the timing distributions of fission products' concentrations and their integrated decay heat as function of time following a fast neutron fission reaction of 232Th were exactly calculated by the numerical method with using the DHP code.

  4. A comparison of microwave versus direct solar heating for lunar brick production

    NASA Technical Reports Server (NTRS)

    Yankee, S. J.; Strenski, D. G.; Pletka, B. J.; Patil, D. S.; Mutsuddy, B. C.

    1990-01-01

    Two processing techniques considered suitable for producing bricks from lunar regolith are examined: direct solar heating and microwave heating. An analysis was performed to compare the two processes in terms of the amount of power and time required to fabricate bricks of various sizes. Microwave heating was shown to be significantly faster than solar heating for rapid production of realistic-size bricks. However, the relative simplicity of the solar collector(s) used for the solar furnace compared to the equipment necessary for microwave generation may present an economic tradeoff.

  5. Correlations in quantum thermodynamics: Heat, work, and entropy production

    PubMed Central

    Alipour, S.; Benatti, F.; Bakhshinezhad, F.; Afsary, M.; Marcantoni, S.; Rezakhani, A. T.

    2016-01-01

    We provide a characterization of energy in the form of exchanged heat and work between two interacting constituents of a closed, bipartite, correlated quantum system. By defining a binding energy we derive a consistent quantum formulation of the first law of thermodynamics, in which the role of correlations becomes evident, and this formulation reduces to the standard classical picture in relevant systems. We next discuss the emergence of the second law of thermodynamics under certain—but fairly general—conditions such as the Markovian assumption. We illustrate the role of correlations and interactions in thermodynamics through two examples. PMID:27767124

  6. Superdormant spores of Bacillus species have elevated wet-heat resistance and temperature requirements for heat activation.

    PubMed

    Ghosh, Sonali; Zhang, Pengfei; Li, Yong-qing; Setlow, Peter

    2009-09-01

    Purified superdormant spores of Bacillus cereus, B. megaterium, and B. subtilis isolated after optimal heat activation of dormant spores and subsequent germination with inosine, d-glucose, or l-valine, respectively, germinate very poorly with the original germinants used to remove dormant spores from spore populations, thus allowing isolation of the superdormant spores, and even with alternate germinants. However, these superdormant spores exhibited significant germination with the original or alternate germinants if the spores were heat activated at temperatures 8 to 15 degrees C higher than the optimal temperatures for the original dormant spores, although the levels of superdormant spore germination were not as great as those of dormant spores. Use of mixtures of original and alternate germinants lowered the heat activation temperature optima for both dormant and superdormant spores. The superdormant spores had higher wet-heat resistance and lower core water content than the original dormant spore populations, and the environment of dipicolinic acid in the core of superdormant spores as determined by Raman spectroscopy of individual spores differed from that in dormant spores. These results provide new information about the germination, heat activation optima, and wet-heat resistance of superdormant spores and the heterogeneity in these properties between individual members of dormant spore populations.

  7. Antiproliferative activity of melanoidins isolated from heated potato fiber (potex) in glioma cell culture model.

    PubMed

    Langner, Ewa; Nunes, Fernando M; Pozarowski, Piotr; Kandefer-Szerszeń, Martyna; Pierzynowski, Stefan G; Rzeski, Wojciech

    2011-03-23

    Potex constitutes a potato fiber preparation widely used as an ingredient to meat and bakery products which thermal treatment results in creation of new compounds. Melanoidins are high molecular weight brown end products of Maillard reaction, and few data presenting tumor cell growth inhibiting activity of melanoidins have been reported. Thus, in present study we utilized water extract of Potex roasted (180 °C for 2 h), whose chemical characterization revealed the presence of melanoidin complexes. Heated Potex extract inhibited C6 glioma cell proliferation in a dose-dependent manner measured by MTT method. High molecular weight components present in initial extract were responsible for stronger antiproliferative effect compared with low molecular weight fraction. Impaired MAPK (mitogen-activated protein kinase) and Akt signaling was found in cells treated with the extract. Moreover, flow cytometry analyses revealed the extract to induce G1/S arrest in glioma cells. Simultaneously, Western blot analysis showed elevated levels of p21 protein with concomitant decrease of cyclin D1. In conclusion, observed antiproliferative activity of melanoidins present in heated Potex was linked to disregulated MAPK and Akt signaling pathways, as well as to cell cycle cessation. These results suggest potential application of Potex preparation as a functional food ingredient and chemopreventive agent.

  8. Sum Product Networks for Activity Recognition.

    PubMed

    Amer, Mohamed R; Todorovic, Sinisa

    2016-04-01

    This paper addresses detection and localization of human activities in videos. We focus on activities that may have variable spatiotemporal arrangements of parts, and numbers of actors. Such activities are represented by a sum-product network (SPN). A product node in SPN represents a particular arrangement of parts, and a sum node represents alternative arrangements. The sums and products are hierarchically organized, and grounded onto space-time windows covering the video. The windows provide evidence about the activity classes based on the Counting Grid (CG) model of visual words. This evidence is propagated bottom-up and top-down to parse the SPN graph for the explanation of the video. The node connectivity and model parameters of SPN and CG are jointly learned under two settings, weakly supervised, and supervised. For evaluation, we use our new Volleyball dataset, along with the benchmark datasets VIRAT, UT-Interactions, KTH, and TRECVID MED 2011. Our video classification and activity localization are superior to those of the state of the art on these datasets.

  9. Superoxide radical production in chicken skeletal muscle induced by acute heat stress.

    PubMed

    Mujahid, A; Yoshiki, Y; Akiba, Y; Toyomizu, M

    2005-02-01

    Heat stress is of major concern for poultry, especially in the hot regions of the world because of the resulting poor growth performance, immunosuppression, and high mortality. To assess superoxide (O2*-) production in mitochondria isolated from skeletal muscle of chickens (n = 4 to 8) exposed to acute heat stress, electron spin resonance (ESR) spectroscopy using 5,5-dimethyl-1-pyrroline N-oxide (DMPO) as a spin trap agent and lucigenin-derived chemiluminescence (LDCL) method were applied. ESR spectra of suspensions containing mitochondria from control and acute heat-treated meat-type chickens showed similar hyperfine coupling constants (aN = 1.44 mT, aHbeta = 0.12 mT, and aHbeta = 0.11 mT) to those of DMPO-O2*- adducts observed in a hypoxanthine-xanthine oxidase system. Heat exposure resulted in enhancement of the DMPO-O2*- signal. The results using LDCL showed significantly enhanced superoxide production in heat stress-treated skeletal muscle mitochondria of meat-type chickens, whereas no such increase was observed in laying chickens. The enhancement of superoxide production in the former case was associated with heat-induced increments in rectal and muscle temperatures, leading to significant body weight loss. In contrast, the latter case showed no increase in temperatures, although there was a slight decrease in body weight gain. Percentage increases of superoxide production in the presence of carboxyatractylate, a specific inhibitor of adenine nucleotide translocator (ANT), were the same for skeletal muscle mitochondria from meat- and laying-type chickens from the control or heat stress-treated group. This finding suggests the irrelevance of ANT in the regulation of reactive oxygen species flux under heat stress conditions. The study provides the first evidence of superoxide anion production in the skeletal muscle mitochondria of meat-type chickens in response to acute heat stress.

  10. Biodiesel production process from microalgae oil by waste heat recovery and process integration.

    PubMed

    Song, Chunfeng; Chen, Guanyi; Ji, Na; Liu, Qingling; Kansha, Yasuki; Tsutsumi, Atsushi

    2015-10-01

    In this work, the optimization of microalgae oil (MO) based biodiesel production process is carried out by waste heat recovery and process integration. The exergy analysis of each heat exchanger presented an efficient heat coupling between hot and cold streams, thus minimizing the total exergy destruction. Simulation results showed that the unit production cost of optimized process is 0.592$/L biodiesel, and approximately 0.172$/L biodiesel can be avoided by heat integration. Although the capital cost of the optimized biodiesel production process increased 32.5% and 23.5% compared to the reference cases, the operational cost can be reduced by approximately 22.5% and 41.6%.

  11. Adaptation to hot climate and strategies to alleviate heat stress in livestock production.

    PubMed

    Renaudeau, D; Collin, A; Yahav, S; de Basilio, V; Gourdine, J L; Collier, R J

    2012-05-01

    Despite many challenges faced by animal producers, including environmental problems, diseases, economic pressure, and feed availability, it is still predicted that animal production in developing countries will continue to sustain the future growth of the world's meat production. In these areas, livestock performance is generally lower than those obtained in Western Europe and North America. Although many factors can be involved, climatic factors are among the first and crucial limiting factors of the development of animal production in warm regions. In addition, global warming will further accentuate heat stress-related problems. The objective of this paper was to review the effective strategies to alleviate heat stress in the context of tropical livestock production systems. These strategies can be classified into three groups: those increasing feed intake or decreasing metabolic heat production, those enhancing heat-loss capacities, and those involving genetic selection for heat tolerance. Under heat stress, improved production should be possible through modifications of diet composition that either promotes a higher intake or compensates the low feed consumption. In addition, altering feeding management such as a change in feeding time and/or frequency, are efficient tools to avoid excessive heat load and improve survival rate, especially in poultry. Methods to enhance heat exchange between the environment and the animal and those changing the environment to prevent or limit heat stress can be used to improve performance under hot climatic conditions. Although differences in thermal tolerance exist between livestock species (ruminants > monogastrics), there are also large differences between breeds of a species and within each breed. Consequently, the opportunity may exist to improve thermal tolerance of the animals using genetic tools. However, further research is required to quantify the genetic antagonism between adaptation and production traits to evaluate

  12. Contrasting Metamorphic Record of Heat Production Anomalies in the Penokean Orogen of Northern Michigan.

    PubMed

    Attoh

    2000-05-01

    It is proposed that the contrasting metamorphic mineral assemblages of the isolated amphibolite facies metamorphic highs in the Penokean orogen of northern Michigan may be caused by different heat production rates in the Archean basement. This hypothesis is based on concentrations of K, U, and Th in the Archean basement gneisses and Paleoproterozoic metasediments that indicate significant contribution of radiogenic heating during Penokean metamorphism. Heat production was anomalously high ( approximately 10.6 µWm-3) where andalusite-bearing mineral assemblages indicate that high temperatures were attained at shallow crustal levels ( approximately 550 degrees -600 degrees C at approximately 3 kbar). In contrast, where exposed metamorphic rocks indicate peak temperatures of 600 degrees -650 degrees C at 6-7 kbar, heat production in the Archean basement was lower ( approximately 3.7 µWm-3). The effect of heat production rates on the metamorphic pressure-temperature paths was tested with numerical thermal models. The calculations show (1) that if the heat production rate, where andalusite-bearing assemblages formed, was significantly <6.0 µWm-3, the estimated pressure at peak temperatures (PTmax) would be much higher and lie in the sillimanite or kyanite stability fields; and (2) differences between PTmax estimates for the metamorphic highs based on thermobarometry can be reproduced if thermal history involved significant crustal thickening as well as moderate unroofing rates. PMID:10769161

  13. Contrasting Metamorphic Record of Heat Production Anomalies in the Penokean Orogen of Northern Michigan.

    PubMed

    Attoh

    2000-05-01

    It is proposed that the contrasting metamorphic mineral assemblages of the isolated amphibolite facies metamorphic highs in the Penokean orogen of northern Michigan may be caused by different heat production rates in the Archean basement. This hypothesis is based on concentrations of K, U, and Th in the Archean basement gneisses and Paleoproterozoic metasediments that indicate significant contribution of radiogenic heating during Penokean metamorphism. Heat production was anomalously high ( approximately 10.6 µWm-3) where andalusite-bearing mineral assemblages indicate that high temperatures were attained at shallow crustal levels ( approximately 550 degrees -600 degrees C at approximately 3 kbar). In contrast, where exposed metamorphic rocks indicate peak temperatures of 600 degrees -650 degrees C at 6-7 kbar, heat production in the Archean basement was lower ( approximately 3.7 µWm-3). The effect of heat production rates on the metamorphic pressure-temperature paths was tested with numerical thermal models. The calculations show (1) that if the heat production rate, where andalusite-bearing assemblages formed, was significantly <6.0 µWm-3, the estimated pressure at peak temperatures (PTmax) would be much higher and lie in the sillimanite or kyanite stability fields; and (2) differences between PTmax estimates for the metamorphic highs based on thermobarometry can be reproduced if thermal history involved significant crustal thickening as well as moderate unroofing rates.

  14. Permafrost thawing in organic Arctic soils accelerated by ground heat production

    NASA Astrophysics Data System (ADS)

    Hollesen, Jørgen; Matthiesen, Henning; Møller, Anders Bjørn; Elberling, Bo

    2015-06-01

    Decomposition of organic carbon from thawing permafrost soils and the resulting release of carbon to the atmosphere are considered to represent a potentially critical global-scale feedback on climate change. The accompanying heat production from microbial metabolism of organic material has been recognized as a potential positive-feedback mechanism that would enhance permafrost thawing and the release of carbon. This internal heat production is poorly understood, however, and the strength of this effect remains unclear. Here, we have quantified the variability of heat production in contrasting organic permafrost soils across Greenland and tested the hypothesis that these soils produce enough heat to reach a tipping point after which internal heat production can accelerate the decomposition processes. Results show that the impact of climate changes on natural organic soils can be accelerated by microbial heat production with crucial implications for the amounts of carbon being decomposed. The same is shown to be true for organic middens with the risk of losing unique evidence of early human presence in the Arctic.

  15. Effects of dietary fermentable carbohydrates on behavior and heat production in group-housed sows.

    PubMed

    Rijnen, M M J A; Verstegen, M W A; Heetkamp, M J W; Haaksma, J; Schrama, J W

    2003-01-01

    The effects of dietary nonstarch polysaccharides (NSP) on behavior and heat production in group-housed sows were studied. Twelve groups of six nonpregnant sows were fed one of four experimental diets that were similar in composition except for starch and NSP contents. Exchanging sugar beet pulp silage (SBPS) for tapioca created the difference in dietary starch and NSP ratio. On a dry matter (DM) basis, diets contained 0, 10, 20, or 30% SBPS. Sows were group-housed. Intake of fermentable NSP (fNSP) for diets containing 0, 10, 20, or 30% SBPS averaged 7.06, 9.18, 11.61, and 13.73 g x kg(-0.75) d(-1), respectively. Sows were fed, once a day at 0800. Dry matter intake for diets containing 0, 10, 20, or 30% SBPS, averaged 38.05, 38.38, 38.53, and 38.35 g x kg(-075) x d(-1), respectively, and ME intake averaged 523, 518, 514, and 493 kJ x kg(-0.75) x d(-1), respectively. On average, sows spent 177 min/d on physical activity, of which 8.8% was spent on eating. Time spent in physical activity was affected by diet (P = 0.005). Sows fed 0 or 10% SBPS spent more time on physical activity than sows fed 20 or 30% SBPS (P = 0.002). Energy cost of physical activity averaged 464 kJ x kg(-0.75) x d(-1) (standard estimated mean of 31) and was similar for diets (P = 0.679). Total heat production (HP) and activity-related heat production (AHP) were affected by diet (P < 0.05). Sows tended to be quieter when fNSP intake increased (P = 0.063). The effect of fNSP intake on HP and AHP was not constant during the day. During the night period, fNSP intake did not affect HP and AHP (P > 0.10). During the day period, increased fNSP intake decreased HP (P = 0.006) and tended to decrease AHP (P = 0.062). During eating, increased fNSP intake increased HP (P = 0.012) and tended to increase AHP (P = 0.074). Despite similar DMI, sows fed 0 or 10% SBPS spent less time eating than sows fed 20 or 30% SBPS (P = 0.009). Feed consumption rate was higher (P = 0.003) in groups fed 0 or 10% SBPS than in

  16. 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.

  17. System for vaporizing carbon dioxide utilizing the heat by-product of the refrigeration system as a heat source

    SciTech Connect

    Shaw, H.L.

    1980-12-23

    The present invention is directed to a carbonation and refrigeration system wherein the heat of the refrigerant output side of the refrigeration compressor is utilized to vaporize liquid carbon dioxide into CO/sub 2/ gas which is introduced into a liquid product. The carbonation and refrigeration system successfully utilizes the heat of the refrigerant to vaporize the CO/sub 2/ liquid regardless of the cooling demand of the system caused by seasonal temperature variations. For example during the winter months when the cooling demand is as low as 10% of the cooling demand in the summer, the carbonation and refrigeration system operates effectively to vaporize the CO/sub 2/ liquid by means of a heat exchanger and a desuperheater which are connected in communication with the superheated vapor emerging from the output side of a refrigeration compressor. In addition, the carbonation and refrigeration system of the present invention cools more efficiently by extracting some of the heat from the condensed refrigerant entering the receiver of the refrigeration system. In this manner, the refrigeration compressor can operate more efficiently.

  18. Degradation of Biochemical Activity in Soil Sterilized by Dry Heat and Gamma Radiation

    NASA Technical Reports Server (NTRS)

    Shih, K. L.; Souza, K. A.

    1978-01-01

    The effect of soil sterilization by dry heat (0.08% relative humidity), gamma radiation, or both on soil phosphatase, urease, and decarboxylase activity was studied. Soil sterilized by a long exposure to dry heat at relatively low temperatures (eight weeks at 100.5 C) retained higher activities than did soil exposed to a higher temperature (two weeks at 124.5 C), while all activity was destroyed by four days at 148.5 C. Sterilization with 7.5 Mrads destroyed less activity than did heat sterilization. The effect of several individually nonsterizing doses of heat radiation is described.

  19. Production Of High Specific Activity Copper-67

    DOEpatents

    Jamriska, Sr., David J.; Taylor, Wayne A.; Ott, Martin A.; Fowler, Malcolm; Heaton, Richard C.

    2003-10-28

    A process for the selective production and isolation of high specific activity Cu.sup.67 from proton-irradiated enriched Zn.sup.70 target comprises target fabrication, target irradiation with low energy (<25 MeV) protons, chemical separation of the Cu.sup.67 product from the target material and radioactive impurities of gallium, cobalt, iron, and stable aluminum via electrochemical methods or ion exchange using both anion and cation organic ion exchangers, chemical recovery of the enriched Zn.sup.70 target material, and fabrication of new targets for re-irradiation is disclosed.

  20. Production Of High Specific Activity Copper-67

    DOEpatents

    Jamriska, Sr., David J.; Taylor, Wayne A.; Ott, Martin A.; Fowler, Malcolm; Heaton, Richard C.

    2002-12-03

    A process for the selective production and isolation of high specific activity cu.sup.67 from proton-irradiated enriched Zn.sup.70 target comprises target fabrication, target irradiation with low energy (<25 MeV) protons, chemical separation of the Cu.sup.67 product from the target material and radioactive impurities of gallium, cobalt, iron, and stable aluminum via electrochemical methods or ion exchange using both anion and cation organic ion exchangers, chemical recovery of the enriched Zn.sup.70 target material, and fabrication of new targets for re-irradiation is disclosed.

  1. Age and heat exposure-dependent changes in antioxidant enzymes activities in rat's liver and brain mitochondria: role of alpha-tocopherol.

    PubMed

    Stojkovski, V; Hadzi-Petrushev, N; Ilieski, V; Sopi, R; Gjorgoski, I; Mitrov, D; Jankulovski, N; Mladenov, M

    2013-01-01

    To investigate the role of mitochondrial antioxidant capacity during increased susceptibility to heat accompanied by the aging, young and aged Wistar rats were exposed on heat for 60 min. After heat exposure, hepatic and brain mitochondria were isolated. Our results revealed changes in antioxidant enzyme activities in liver and brain mitochondria from young and to a greater extent in aged rats. Our measurements of MnSOD, GPx and GR activity indicate greater reactive oxygen species production from the mitochondria of aged heat exposed in comparison to young heat exposed rats. Also in the aged rats, the effect of alpha-tocopherol treatment in the prevention of oxidative stress occurred as a result of heat exposure, is less pronounced. Taken together, our data suggest that mitochondria in aged rats are more vulnerable and less able to prevent oxidative changes that occur in response to acute heat exposure.

  2. Heat Production During Countermeasure Exercises Planned for the International Space Station

    NASA Technical Reports Server (NTRS)

    Rapley, Michael G.; Lee, Stuart M. C.; Guilliams, Mark E.; Greenisen, Michael C.; Schneider, Suzanne M.

    2004-01-01

    This investigation's purpose was to determine the amount of heat produced when performing aerobic and resistance exercises planned as part of the exercise countermeasures prescription for the ISS. These data will be used to determine thermal control requirements of the Node 1 and other modules where exercise hardware might reside. To determine heat production during resistive exercise, 6 subjects using the iRED performed 5 resistance exercises which form the core exercises of the current ISS resistive exercise countermeasures. Each exerciser performed a warm-up set at 50% effort, then 3 sets of increasing resistance. We measured oxygen consumption and work during each exercise. Heat loss was calculated as the difference between the gross energy expenditure (minus resting metabolism) and the work performed. To determine heat production during aerobic exercise, 14 subjects performed an interval, cycle exercise protocol and 7 subjects performed a continuous, treadmill protocol. Each 30-min. exercise is similar to exercises planned for ISS. Oxygen consumption monitored continuously during the exercises was used to calculate the gross energy expenditure. For cycle exercise, work performed was calculated based on the ergometer's resistance setting and pedaling frequency. For treadmill, total work was estimated by assuming 25% work efficiency and subtracting the calculated heat production and resting metabolic rate from the gross energy expenditure. This heat production needs to be considered when determining the location of exercise hardware on ISS and designing environmental control systems. These values reflect only the human subject s produced heat; heat produced by the exercise hardware also will contribute to the heat load.

  3. Active region emission measure distributions and implications for nanoflare heating

    SciTech Connect

    Cargill, P. J.

    2014-03-20

    The temperature dependence of the emission measure (EM) in the core of active regions coronal loops is an important diagnostic of heating processes. Observations indicate that EM(T) ∼ T{sup a} below approximately 4 MK, with 2 < a < 5. Zero-dimensional hydrodynamic simulations of nanoflare trains are used to demonstrate the dependence of a on the time between individual nanoflares (T{sub N} ) and the distribution of nanoflare energies. If T{sub N} is greater than a few thousand seconds, a < 3. For smaller values, trains of equally spaced nanoflares cannot account for the observed range of a if the distribution of nanoflare energies is either constant, randomly distributed, or a power law. Power law distributions where there is a delay between consecutive nanoflares proportional to the energy of the second nanoflare do lead to the observed range of a. However, T{sub N} must then be of the order of hundreds to no more than a few thousand seconds. If a nanoflare leads to the relaxation of a stressed coronal field to a near-potential state, the time taken to build up the required magnetic energy is thus too long to account for the EM measurements. Instead, it is suggested that a nanoflare involves the relaxation from one stressed coronal state to another, dissipating only a small fraction of the available magnetic energy. A consequence is that nanoflare energies may be smaller than previously envisioned.

  4. Kinetic and mechanistic investigations of the degradation of sulfamethazine in heat-activated persulfate oxidation process.

    PubMed

    Fan, Yan; Ji, Yuefei; Kong, Deyang; Lu, Junhe; Zhou, Quansuo

    2015-12-30

    Sulfamethazine (SMZ) is widely used in livestock feeding and aquaculture as an antibiotic agent and growth promoter. Widespread occurrence of SMZ in surface water, groundwater, soil and sediment has been reported. In this study, degradation of SMZ by heat-activated persulfate (PS) oxidation was investigated in aqueous solution. Experimental results demonstrated that SMZ degradation followed pseudo-first-order reaction kinetics. The pseudo-first-order rate constant (kobs) was increased markedly with increasing concentration of PS and temperature. Radical scavenging tests revealed that the predominant oxidizing species was SO4·(-) with HO playing a less important role. Aniline moiety in SMZ molecule was confirmed to be the reactive site for SO4·(-) attack by comparison with substructural analogs. Nontarget natural water constituents affected SMZ removal significantly, e.g., Cl(-) and HCO3(-) improved the degradation while fulvic acid reduced it. Reaction products were enriched by solid phase extraction (SPE) and analyzed by liquid chromatography-electrospray ionization-triple quadrupole mass spectrometry (LC-ESI-MS/MS). 6 products derived from sulfonamide S--N bond cleavage, aniline moiety oxidation and Smiles-type rearrangement were identified, and transformation pathways of SMZ oxidation were proposed. Results reveal that heat-activated PS oxidation could be an efficient approach for remediation of water contaminated by SMZ and related sulfonamides.

  5. Heat stress activates the yeast high-osmolarity glycerol mitogen-activated protein kinase pathway, and protein tyrosine phosphatases are essential under heat stress.

    PubMed

    Winkler, Astrid; Arkind, Christopher; Mattison, Christopher P; Burkholder, Anne; Knoche, Kathryn; Ota, Irene

    2002-04-01

    The yeast high-osmolarity glycerol (HOG) mitogen-activated protein kinase (MAPK) pathway has been characterized as being activated solely by osmotic stress. In this work, we show that the Hog1 MAPK is also activated by heat stress and that Sho1, previously identified as a membrane-bound osmosensor, is required for heat stress activation of Hog1. The two-component signaling protein, Sln1, the second osmosensor in the HOG pathway, was not involved in heat stress activation of Hog1, suggesting that the Sho1 and Sln1 sensors discriminate between stresses. The possible function of Hog1 activation during heat stress was examined, and it was found that the hog1 delta strain does not recover as rapidly from heat stress as well as the wild type. It was also found that protein tyrosine phosphatases (PTPs) Ptp2 and Ptp3, which inactivate Hog1, have two functions during heat stress. First, they are essential for survival at elevated temperatures, preventing lethality due to Hog1 hyperactivation. Second, they block inappropriate cross talk between the HOG and the cell wall integrity MAPK pathways, suggesting that PTPs are important for maintaining specificity in MAPK signaling pathways. PMID:12455951

  6. Heat Stress Activates the Yeast High-Osmolarity Glycerol Mitogen-Activated Protein Kinase Pathway, and Protein Tyrosine Phosphatases Are Essential under Heat Stress

    PubMed Central

    Winkler, Astrid; Arkind, Christopher; Mattison, Christopher P.; Burkholder, Anne; Knoche, Kathryn; Ota, Irene

    2002-01-01

    The yeast high-osmolarity glycerol (HOG) mitogen-activated protein kinase (MAPK) pathway has been characterized as being activated solely by osmotic stress. In this work, we show that the Hog1 MAPK is also activated by heat stress and that Sho1, previously identified as a membrane-bound osmosensor, is required for heat stress activation of Hog1. The two-component signaling protein, Sln1, the second osmosensor in the HOG pathway, was not involved in heat stress activation of Hog1, suggesting that the Sho1 and Sln1 sensors discriminate between stresses. The possible function of Hog1 activation during heat stress was examined, and it was found that the hog1Δ strain does not recover as rapidly from heat stress as well as the wild type. It was also found that protein tyrosine phosphatases (PTPs) Ptp2 and Ptp3, which inactivate Hog1, have two functions during heat stress. First, they are essential for survival at elevated temperatures, preventing lethality due to Hog1 hyperactivation. Second, they block inappropriate cross talk between the HOG and the cell wall integrity MAPK pathways, suggesting that PTPs are important for maintaining specificity in MAPK signaling pathways. PMID:12455951

  7. Mitigation of heat stress-related complications by a yeast fermentate product.

    PubMed

    Giblot Ducray, Henri Alexandre; Globa, Ludmila; Pustovyy, Oleg; Reeves, Stuart; Robinson, Larry; Vodyanoy, Vitaly; Sorokulova, Iryna

    2016-08-01

    Heat stress results in a multitude of biological and physiological responses which can become lethal if not properly managed. It has been shown that heat stress causes significant adverse effects in both human and animals. Different approaches have been proposed to mitigate the adverse effects caused by heat stress, among which are special diet and probiotics. We characterized the effect of the yeast fermentate EpiCor (EH) on the prevention of heat stress-related complications in rats. We found that increasing the body temperature of animals from 37.1±0.2 to 40.6±0.2°C by exposure to heat (45°C for 25min) resulted in significant morphological changes in the intestine. Villi height and total mucosal thickness decreased in heat-stressed rats pre-treated with PBS in comparison with control animals not exposed to the heat. Oral treatment of rats with EH before heat stress prevented the traumatic effects of heat on the intestine. Changes in intestinal morphology of heat-stressed rats, pre-treated with PBS resulted in significant elevation of lipopolysaccharides (LPS) level in the serum of these animals. Pre-treatment with EH was effective in the prevention of LPS release into the bloodstream of heat-stressed rats. Our study revealed that elevation of body temperature also resulted in a significant increase of the concentration of vesicles released by erythrocytes in rats, pre-treated with PBS. This is an indication of a pathological impact of heat on the erythrocyte structure. Treatment of rats with EH completely protected their erythrocytes from this heat-induced pathology. Finally, exposure to heat stress conditions resulted in a significant increase of white blood cells in rats. In the group of animals pre-treated with EH before heat stress, the white blood cell count remained the same as in non-heated controls. These results showed the protective effect of the EH product in the prevention of complications, caused by heat stress. PMID:27503713

  8. HEAT INPUT AND POST WELD HEAT TREATMENT EFFECTS ON REDUCED-ACTIVATION FERRITIC/MARTENSITIC STEEL FRICTION STIR WELDS

    SciTech Connect

    Tang, Wei; Chen, Gaoqiang; Chen, Jian; Yu, Xinghua; Frederick, David Alan; Feng, Zhili

    2015-01-01

    Reduced-activation ferritic/martensitic (RAFM) steels are an important class of structural materials for fusion reactor internals developed in recent years because of their improved irradiation resistance. However, they can suffer from welding induced property degradations. In this paper, a solid phase joining technology friction stir welding (FSW) was adopted to join a RAFM steel Eurofer 97 and different FSW parameters/heat input were chosen to produce welds. FSW response parameters, joint microstructures and microhardness were investigated to reveal relationships among welding heat input, weld structure characterization and mechanical properties. In general, FSW heat input results in high hardness inside the stir zone mostly due to a martensitic transformation. It is possible to produce friction stir welds similar to but not with exactly the same base metal hardness when using low power input because of other hardening mechanisms. Further, post weld heat treatment (PWHT) is a very effective way to reduce FSW stir zone hardness values.

  9. Subtask 12D1: Impact properties of production heat of V-4Cr-4Ti

    SciTech Connect

    Chung, H.M.; Nowicki, L.; Smith, D.L.

    1995-03-01

    Following previous reports of excellent properties of a laboratory heat of V-4Cr-4Ti, the alloy identified as the primary vanadium-based candidate for application as fusion reactor structural components, a large production-scale (500-kg) heat of the alloy was fabricated successfully. Since impact toughness has been known to be most sensitive to alloy composition and microstructure, impact testing of the production-scale heat was conducted in this work between -200{degrees}C and +200{degrees}C. A 500-kg heat of V-4Cr-4Ti, an alloy identified previously as the primary vanadium-based candidate alloy for application as fusion reactor structural components, has been produced successfully. Impact tests were conducted at -196{degrees}C to 150{degrees}C on 1/3-size Charpy specimens of the scale-up heat in as-rolled condition and after annealing for 1 h at 950, 1000, and 1050{degrees}C in high-quality vacuum. The annealed material remained ductile at all test temperatures; the ductile-brittle transition temperature (DBTT) was lower than -200{degrees}C. The upper-shelf energy of the production-scale heat was similar to that of the laboratory-scale ({approx}30-kg) heat of V-4Cr-4Ti investigated previously. Effect of annealing temperature was not significant; however, annealing at 1000{degrees}C for 1 h not only produces best impact properties but also ensures a sufficient tolerance to effect of temperature inhomogeneity expected when annealing large components. Effect of notch geometry was also investigated on the production heat. When annealed properly (e.g., at 1000{degrees}C for 1 h), impact properties were not sensitive to notch geometry (45{degrees}-notch, root radius 0.25 mm; and 300-notch, root radius 0.08 mm). 11 refs., 6 figs., 1 tab.

  10. Heat transfer in citric Acid production with axial and radial flow impellers.

    PubMed

    Merwe, Jacob D van der; Minarik, Martin; Berovič, Marin; Herakovič, Niko

    2010-03-01

    In order to produce fermentation broth for downstream recovery, a total of 15 fermentations were done in a 15 m3 and two 7.5 m3 vessels. Apart from the evaluation of fermentation yield and productivity, information on the heat and mass transfer coefficients were required for design purposes. The focus of the fermentation study was therefore directed to obtain information on broth rheology, heat transfer aspects and considerations. Broth rheology was found to deviate from Newtonian behavior with increasing biomass concentration. Using axial flow impellers, rather than radial flow producing Rushton turbines, significantly improved heat transfer in this study. PMID:24061667

  11. Greenhouse soil heating for improved production and energy conservation. Final report

    SciTech Connect

    Roller, W.L.; Elwell, D.L.

    1981-09-01

    A three-year study of the beneficial use of simulated power plant reject heat for soil heating in greenhouses is described. The effect of 25, 30, 35, and 40/sup 0/C warm water on the temperature of and moisture distribution in three diverse, greenhouse soils was studied, and the growth response of variety HR-5 lettuce in this environment was determined. Detailed information on soil temperature and moisture distribution, heat transfer rates, and lettuce production yield under various operating conditions was obtained.

  12. Vacuum evaporation treatment of digestate: full exploitation of cogeneration heat to process the whole digestate production.

    PubMed

    Guercini, S; Castelli, G; Rumor, C

    2014-01-01

    Vacuum evaporation represents an interesting and innovative solution for managing animal waste surpluses in areas with high livestock density. To reduce operational costs, a key factor is the availability of an inexpensive source of heat, such as that coming from an anaerobic digestion (AD) plant. The aim of this study was to test vacuum evaporation for the treatment of cattle slurry digestate focusing on heat exploitation. Tests were performed with a pilot plant fed with the digestate from a full-scale AD plant. The results were used to evaluate if and how cogeneration heat can support both the AD plant and the subsequent evaporation of the whole daily digestate production in a full-scale plant. The concentrate obtained (12% total solids) represents 40-50% of the influent. The heat requirement is 0.44 kWh/kg condensate. Heat power availability exceeding the needs of the digestor ranges from 325 (in winter) to 585 kW (in summer) versus the 382 kW required for processing the whole digestate production. To by-pass fluctuations, we propose to use the heat coming from the cogenerator directly in the evaporator, tempering the digestor with the latent heat of distillation vapor.

  13. Materials experience and selection for nuclear materials production reactor heat exchangers

    SciTech Connect

    Marra, J.E.; Louthan, M.R. Jr.

    1990-01-01

    The primary coolant systems for the heavy-water nuclear materials production reactors at the Savannah River Site are coupled to the secondary coolant systems through shell and tube heat exchangers. The head, shell, and tube sheets of these heat exchangers are fabricated from AISI Type 304 grades of austenitic stainless steel. The 8,957 tubes in each heat exchanger were originally fabricated from Type 304 stainless steel, but service experience has lead to the use of Sea Cure tubing in newer systems. The design includes double tube sheets, core rods, and 33,410 square feet of heat transfer surface. Tubes are rolled into the tube sheets and seal welded after rolling. The tubes contain Type 304 stainless steel rods which are positioned in the center of each tube axis to increase the fraction of the cooling water contacting the heat transfer surface. Each reactor utilizes twelve heat exchangers; thus the 120+ reactor-years of operating experience provide approximately 1,440 heat exchanger-years of service. Fatigue, stress corrosion cracking, crevice corrosion, and pitting have been observed during the service life. This paper describes the observed degradation processes and uses the operational experience to recommend materials for the Heavy Water -- New Production Reactor (HW-NPR).

  14. Theoretical Design of a Thermosyphon for Efficient Process Heat Removal from Next Generation Nuclear Plant (NGNP) for Production of Hydrogen

    SciTech Connect

    Piyush Sabharwall; Fred Gunnerson; Akira Tokuhiro; Vivek Utgiker; Kevan Weaver; Steven Sherman

    2007-10-01

    The work reported here is the preliminary analysis of two-phase Thermosyphon heat transfer performance with various alkali metals. Thermosyphon is a device for transporting heat from one point to another with quite extraordinary properties. Heat transport occurs via evaporation and condensation, and the heat transport fluid is re-circulated by gravitational force. With this mode of heat transfer, the thermosyphon has the capability to transport heat at high rates over appreciable distances, virtually isothermally and without any requirement for external pumping devices. For process heat, intermediate heat exchangers (IHX) are required to transfer heat from the NGNP to the hydrogen plant in the most efficient way possible. The production of power at higher efficiency using Brayton Cycle, and hydrogen production requires both heat at higher temperatures (up to 1000oC) and high effectiveness compact heat exchangers to transfer heat to either the power or process cycle. The purpose for selecting a compact heat exchanger is to maximize the heat transfer surface area per volume of heat exchanger; this has the benefit of reducing heat exchanger size and heat losses. The IHX design requirements are governed by the allowable temperature drop between the outlet of the NGNP (900oC, based on the current capabilities of NGNP), and the temperatures in the hydrogen production plant. Spiral Heat Exchangers (SHE’s) have superior heat transfer characteristics, and are less susceptible to fouling. Further, heat losses to surroundings are minimized because of its compact configuration. SHEs have never been examined for phase-change heat transfer applications. The research presented provides useful information for thermosyphon design and Spiral Heat Exchanger.

  15. Nitric oxide induces heat-shock protein 70 expression in vascular smooth muscle cells via activation of heat shock factor 1.

    PubMed Central

    Xu, Q; Hu, Y; Kleindienst, R; Wick, G

    1997-01-01

    Current data suggest that nitric oxide (NO) is a double-edged sword that could result in relaxation and/or cytotoxicity of vascular smooth muscle cells (SMCs) via cGMP- dependent or -independent signal pathways. Stress or heat shock proteins (hsps) have been shown to be augmented in arterial SMCs during acute hypertension and atherosclerosis, both conditions that are believed to correlate with disturbed NO production. In the present study, we demonstrate that NO generated from sodium nitroprusside (SNP), S-nitroso-N-acetylpenicillamine, and spermine/nitric oxide complex leads to hsp70 induction in cultured SMCs. Western blot analysis demonstrated that hsp70 protein expression peaked between 6 and 12 h after treatment with SNP, and elevated protein levels were preceded by induction of hsp70 mRNA within 3 h. Induction of hsp70 mRNA was associated with the activation of heat shock transcription factor 1 (HSF1), suggesting that the response was regulated at the transcriptional level. HSF1 activation was completely blocked by hemoglobin, dithiothreitol, and cycloheximide, suggesting that the protein damage and nascent polypeptide formation induced by NO may initiate this activation. Furthermore, SMCs pretreated with heat shock (42 degrees C) for 30 min were significantly protected from death induced by NO. Thus, we provide evidence that NO induces hsp70 expression in SMCs via HSF1 activation. Induction of hsp70 could be important in protecting SMCs from injury resulting from NO stimulation. PMID:9276725

  16. Potential techniques and development activities in diver suit heating

    NASA Technical Reports Server (NTRS)

    Shlosinger, A. P.

    1972-01-01

    A prototype compact reactor suitable for combustion of propane with oxygen under shallow as well as submerged deep submergence diving conditions is reported. The device is used to heat the circulating water in a water tube-type diving suit.

  17. Production and physiological responses of heat-stressed lactating dairy cattle to conductive cooling.

    PubMed

    Perano, Kristen M; Usack, Joseph G; Angenent, Largus T; Gebremedhin, Kifle G

    2015-08-01

    The objective of this research was to test the effectiveness of conductive cooling in alleviating heat stress of lactating dairy cows. A conductive cooling system was built with waterbeds (Dual Chamber Cow Waterbeds, Advanced Comfort Technology Inc., Reedsburg, WI) modified to circulate chilled water. The experiment lasted 7 wk. Eight first-lactation Holstein cows producing 34.4±3.7kg/d of milk at 166±28 d in milk were used in the study. Milk yield, dry matter intake (DMI), and rectal temperature were recorded twice daily, and respiration rate was recorded 5 times per day. During wk 1, the cows were not exposed to experimental heat stress or conductive cooling. For the remaining 6 wk, the cows were exposed to heat stress from 0900 to 1700h each day. During these 6 wk, 4 of the 8 cows were cooled with conductive cooling (experimental cows), and the other 4 were not cooled (control cows). The study consisted of 2 thermal environment exposures (temperature-humidity index mean ± standard deviation of 80.7±0.9 and 79.0±1.0) and 2 cooling water temperatures (circulating water through the water mattresses at temperatures of 4.5°C and 10°C). Thus, a total of 4 conductive cooling treatments were tested, with each treatment lasting 1 wk. During wk 6, the experimental and control cows were switched and the temperature-humidity index of 79.0±1.0 with 4.5°C cooling water treatment was repeated. During wk 7, waterbeds were placed directly on concrete stalls without actively cooling the water. Least squares means and P-values for the different treatments were calculated with multivariate mixed models. Conductively cooling the cows with 4.5°C water decreased rectal temperature by 1.0°C, decreased respiration rate by 18 breaths/min, increased milk yield by 5%, and increased DMI by 14% compared with the controls. When the results from the 2 cooling water temperatures (4.5°C and 10°C circulating water) were compared, we found that the rectal temperature from 4.5

  18. An evaluation of alternate production methods for Pu-238 general purpose heat source pellets

    SciTech Connect

    Mark Borland; Steve Frank

    2009-06-01

    For the past half century, the National Aeronautics and Space Administration (NASA) has used Radioisotope Thermoelectric Generators (RTG) to power deep space satellites. Fabricating heat sources for RTGs, specifically General Purpose Heat Sources (GPHSs), has remained essentially unchanged since their development in the 1970s. Meanwhile, 30 years of technological advancements have been made in the applicable fields of chemistry, manufacturing and control systems. This paper evaluates alternative processes that could be used to produce Pu 238 fueled heat sources. Specifically, this paper discusses the production of the plutonium-oxide granules, which are the input stream to the ceramic pressing and sintering processes. Alternate chemical processes are compared to current methods to determine if alternative fabrication processes could reduce the hazards, especially the production of respirable fines, while producing an equivalent GPHS product.

  19. Cure of Trypanosoma musculi infection by heat-labile activity in immune plasma.

    PubMed

    Wechsler, D S; Kongshavn, P A

    1984-06-01

    Passive transfer of plasma from a mouse cured of parasitemia to a Trypanosoma musculi-infected host rapidly eliminates parasitemia; this curative activity, presumably mediated by an immunoglobulin, is sensitive to heat treatment (56 degrees C, 30 min). In addition, pretreatment with immune plasma, even after heat treatment, prevents the development of a patent parasitemia in a naive host (protective activity).

  20. Enhancement of lactase activity in milk by reactive sulfhydryl groups induced by heat treatment.

    PubMed

    Jiménez-Guzmán, J; Cruz-Guerrero, A E; Rodríguez-Serrano, G; López-Munguía, A; Gómez-Ruiz, L; García-Garibay, M

    2002-10-01

    The effects of heat treatments of milk and whey prior to lactose hydrolysis with Kluyveromyces lactis beta-galactosidase were studied. It was observed that heat treatment of milk significantly increases lactase activity, with a maximum activity increase found when milk was heated at 55 degrees C. In whey from 55 up to 75 degrees C, beta-galactosidase activity decreased slightly. Nevertheless, heating whey at 85 degrees C for 30 min raised the rate of hydrolysis significantly. Electrophoretic patterns and UV spectra proved that the activity change correlated with milk protein denaturation, particularly that of beta-lactoglobulin. Heating whey permeate did not increase the enzyme activity as heating whole whey; but heating whey prior to ultrafiltration also resulted in enzyme activation. Measurement of free sulfhydryl (SH) groups in both whey and heated whey permeate showed that the liberation of free SH is highly correlated to the change of the activity. Furthermore, this activation can be reversed by oxidizing the reactive sulfhydryl groups, proving that the observed effect may be related to the release of free SH to the medium, rather than to the denaturation of a thermolabile protein inhibitor.

  1. Analysis of Competitiveness and Support Instruments for Heat and Electricity Production from Wood Biomass in Latvia

    NASA Astrophysics Data System (ADS)

    Klavs, G.; Kudrenickis, I.; Kundzina, A.

    2012-01-01

    Utilisation of renewable energy sources is one of the key factors in a search for efficient ways of reducing the emissions of greenhouse gases and improving the energy supply security. So far, the district heating supply in Latvia has been based on natural gas, with the wood fuel playing a minor role; the same is true for decentralised combined heat-power (CHP) production. The paper describes a method for evaluation of the economic feasibility of heat and electricity production from wood biomass under the competition between different fuel types and taking into account the electricity market. For the simulation, a cost estimation model is applied. The results demonstrate that wood biomass can successfully be utilised for competitive heat production by boiler houses, while for electricity production by CHP utilities it cannot compete on the market (even despite the low prices on wood biomass fuel) unless particular financial support instruments are applied. The authors evaluate the necessary support level and the impact of two main support instruments - the investment subsidies and the feed-in tariff - on the economic viability of wood-fuelled CHP plants, and show that the feed-in tariff could be considered as an instrument strongly affecting the competitiveness of such type CHP. Regarding the feed-in tariff determination, a compromise should be found between the economy-dictated requirement to develop CHP projects concerning capacities above 5 MWel - on the one hand, and the relatively small heat loads in many Latvian towns - on the other.

  2. Thermophilic biohydrogen production by an anaerobic heat treated-hot spring culture.

    PubMed

    Karadag, Dogan; Mäkinen, Annukka E; Efimova, Elena; Puhakka, Jaakko A

    2009-12-01

    Batch experiments were conducted to investigate the thermophilic biohydrogen production using an enrichment culture from a Turkish hot spring. Following the enrichment, the culture was heat treated at 100 degrees C for 10 min to select for spore-forming bacteria. H(2) production was accompanied by production of acetate, butyrate, lactate and ethanol. H(2) production was associated by acetate-butyrate type fermentation while accumulation of lactate and ethanol negatively affected the H(2) yield. H(2) production was highest in the temperature range from 49.6 to 54.8 degrees C and optimum values for initial pH and concentrations of iron, yeast extract and glucose were 6.5, 40 mg/l, 4-13.5 g/l, respectively. PCR-DGGE profiling showed that the heat treated culture consisted of species closely affiliated to genus Thermoanaerobacterium.

  3. Performance of active solar space-heating systems, 1980-1981 heating season

    SciTech Connect

    Welch, K.; Kendall, P.; Pakkala, P.; Cramer, M.

    1981-01-01

    Data are provided on 32 solar heating sites in the National Solar Data Network (NSDN). Of these, comprehensive data are included for 14 sites which cover a range of system types and solar applications. A brief description of the remaining sites is included along with system problems experienced which prevented comprehensive seasonal analyses. Tables and discussions of individual site parameters such as collector areas, storage tank sizes, manufacturers, building dimensions, etc. are provided. Tables and summaries of 1980-1981 heating season data are also provided. Analysis results are presented in graphic form to highlight key summary information. Performance indices are graphed for two major groups of collectors - liquid and air. Comparative results of multiple NSDN systems' operation for the 1980-1981 heating season are summarized with discussions of specific cases and conclusions which may be drawn from the data. (LEW)

  4. Heat Pipe Solar Receiver Development Activities at Sandia National Laboratories

    SciTech Connect

    Adkins, D.R.; Andraka, C.E.; Moreno, J.B.; Moss, T.A.; Rawlinson, K.S.; Showalter, S.K.

    1999-01-08

    Over the past decade, Sandia National Laboratories has been involved in the development of receivers to transfer energy from the focus of a parabolic dish concentrator to the heater tubes of a Stirling engine. Through the isothermal evaporation and condensation of sodium. a heat-pipe receiver can efficiently transfer energy to an engine's working fluid and compensate for irregularities in the flux distribution that is delivered by the concentrator. The operation of the heat pipe is completely passive because the liquid sodium is distributed over the solar-heated surface by capillary pumping provided by a wick structure. Tests have shown that using a heat pipe can boost the system performance by twenty percent when compared to directly illuminating the engine heater tubes. Designing heat pipe solar receivers has presented several challenges. The relatively large area ({approximately}0.2 m{sup 2}) of the receiver surface makes it difficult to design a wick that can continuously provide liquid sodium to all regions of the heated surface. Selecting a wick structure with smaller pores will improve capillary pumping capabilities of the wick, but the small pores will restrict the flow of liquid and generate high pressure drops. Selecting a wick that is comprised of very tine filaments can increase the permeability of the wick and thereby reduce flow losses, however, the fine wick structure is more susceptible to corrosion and mechanical damage. This paper provides a comprehensive review of the issues encountered in the design of heat pipe solar receivers and solutions to problems that have arisen. Topics include: flow characterization in the receiver, the design of wick systems. the minimization of corrosion and dissolution of metals in sodium systems. and the prevention of mechanical failure in high porosity wick structures.

  5. Numerical model of heat conduction in active volcanoes induced by magmatic activity

    NASA Astrophysics Data System (ADS)

    Atmojo, Antono Arif; Rosandi, Yudi

    2015-09-01

    We study the heat transfer mechanism of active volcanoes using the numerical thermal conduction model. A 2D model of volcano with its conduit filled by magma is considered, and acts as a constant thermal source. The temperature of the magma activity diffuses through the rock layers of the mountain to the surface. The conduction equation is solved using finite-difference method, with some adaptations to allow temperature to flow through different materials. Our model allows to simulate volcanoes having dikes, branch-pipes, and sills by constructing the domain appropriately, as well as layers with different thermal properties. Our research will show the possibility to monitor magma activity underneath a volcano by probing its surface temperature. The result of our work will be very useful for further study of volcanoes, eruption prediction, and volcanic disaster mitigation.

  6. Effects of different heat treatments on lysozyme quantity and antimicrobial activity of jenny milk.

    PubMed

    Cosentino, C; Labella, C; Elshafie, H S; Camele, I; Musto, M; Paolino, R; D'Adamo, C; Freschi, P

    2016-07-01

    Thermal treatments are used to improve milk microbial safety, shelf life, and biological activity of some of its components. However, thermal treatments can reduce the nutritional quality of milk, affecting the molecular structure of milk proteins, such as lysozyme, which is a very important milk component due to its antimicrobial effect against gram-positive bacteria. Jenny milk is characterized by high lysozyme content. For this reason, in the last few years, it has been used as an antimicrobial additive in dairy products as an alternative to hen egg white lysozyme, which can cause allergic reactions. This study aimed to investigate the effect of pasteurization and condensation on the concentration and antimicrobial activity of lysozyme in jenny milk. Furthermore, lysozyme quantity and activity were tested in raw and pasteurized milk after condensation at 40 and 20% of the initial volume. Reversed-phase HPLC was performed under fluorescence detection to monitor lysozyme in milk samples. We evaluated the antimicrobial activity of the tested milk against Bacillus megaterium, Bacillus mojavensis, Clavibacter michiganensis, Clostridium tyrobutyricum, Xanthomonas campestris, and Escherichia coli. Condensation and pasteurization did not affect the concentration or antimicrobial activity of lysozyme in jenny milk, except for B. mojaventis, which showed resistance to lysozyme in milk samples subjected to heat treatments. Moreover, lysozyme in jenny milk showed antimicrobial activity similar to synthetic antibiotics versus some gram-positive strains and also versus the gram-negative strain X. campestris. PMID:27157571

  7. Production of high specific activity silicon-32

    SciTech Connect

    Phillips, D.R.; Brzezinski, M.A.

    1998-12-31

    This is the final report of a three-year, Laboratory Directed Research and Development Project (LDRD) at Los Alamos National Laboratory (LANL). There were two primary objectives for the work performed under this project. The first was to take advantage of capabilities and facilities at Los Alamos to produce the radionuclide {sup 32}Si in unusually high specific activity. The second was to combine the radioanalytical expertise at Los Alamos with the expertise at the University of California to develop methods for the application of {sup 32}Si in biological oceanographic research related to global climate modeling. The first objective was met by developing targetry for proton spallation production of {sup 32}Si in KCl targets and chemistry for its recovery in very high specific activity. The second objective was met by developing a validated field-useable, radioanalytical technique, based upon gas-flow proportional counting, to measure the dynamics of silicon uptake by naturally occurring diatoms.

  8. Mitochondrial reactive oxygen species production by fish muscle mitochondria: Potential role in acute heat-induced oxidative stress.

    PubMed

    Banh, Sheena; Wiens, Lilian; Sotiri, Emianka; Treberg, Jason R

    2016-01-01

    Acute heat challenge is known to induce cell-level oxidative stress in fishes. Mitochondria are well known for the capacity to make reactive oxygen species (ROS) and as such are often implicated as a source of the oxidants associated with this thermally-induced oxidative stress. This implication is often asserted, despite little direct data for mitochondrial ROS metabolism in fishes. Here we characterize mitochondrial ROS metabolism in three Actinopterygian fish species at two levels, the capacity for superoxide/H2O2 production and the antioxidant thiol-reductase enzyme activities. We find that red muscle mitochondria from all three species have measurable ROS production and respond to different assay conditions consistent with what might be anticipated; assuming similar relative contributions from difference ROS producing sites as found in rat skeletal muscle mitochondria. Although there are species and assay specific exceptions, fish mitochondria may have a greater capacity to produce ROS than that found in the rat when either normalized to respiratory capacity or determined at a common assay temperature. The interspecific differences in ROS production are not correlated with thiol-based antioxidant reductase activities. Moreover, mimicking an acute in vivo heat stress by comparing the impact of increasing assay temperature on these processes in vitro, we find evidence supporting a preferential activation of mitochondrial H2O2 production relative to the increase in the capacity of reductase enzymes to supply electrons to the mitochondrial matrix peroxidases. This supports the contention that mitochondria may be, at least in part, responsible for the ROS that lead to oxidative stress in fish tissues exposed to acute heat challenge.

  9. Heat-activated Plasmonic Chemical Sensors for Harsh Environments

    SciTech Connect

    Carpenter, Michael; Oh, Sang-Hyun

    2015-12-01

    A passive plasmonics based chemical sensing system to be used in harsh operating environments was investigated and developed within this program. The initial proposed technology was based on combining technologies developed at the SUNY Polytechnic Institute Colleges of Nanoscale Science and Engineering (CNSE) and at the University of Minnesota (UM). Specifically, a passive wireless technique developed at UM was to utilize a heat-activated plasmonic design to passively harvest the thermal energy from within a combustion emission stream and convert this into a narrowly focused light source. This plasmonic device was based on a bullseye design patterned into a gold film using focused ion beam methods (FIB). Critical to the design was the use of thermal stabilizing under and overlayers surrounding the gold film. These stabilizing layers were based on both atomic layer deposited films as well as metal laminate layers developed by United Technologies Aerospace Systems (UTAS). While the bullseye design was never able to be thermally stabilized for operating temperatures of 500oC or higher, an alternative energy harvesting design was developed by CNSE within this program. With this new development, plasmonic sensing results are presented where thermal energy is harvested using lithographically patterned Au nanorods, replacing the need for an external incident light source. Gas sensing results using the harvested thermal energy are in good agreement with sensing experiments, which used an external incident light source. Principal Component Analysis (PCA) was used to reduce the wavelength parameter space from 665 variables down to 4 variables with similar levels of demonstrated selectivity. The method was further improved by patterning rods which harvested energy in the near infrared, which led to a factor of 10 decrease in data acquisition times as well as demonstrated selectivity with a reduced wavelength data set. The combination of a plasmonic-based energy harvesting

  10. Nuclear data production, calculation and measurement: a global overview of the gamma heating issue

    NASA Astrophysics Data System (ADS)

    Colombier, A.-C.; Amharrak, H.; Fourmentel, D.; Ravaux, S.; Régnier, D.; Gueton, O.; Hudelot, J.-P.; Lemaire, M.

    2013-03-01

    The gamma heating evaluation in different materials found in current and future generations of nuclear reactor (EPRTM, GENIV, MTR-JHR), is becoming an important issue especially for the design of many devices (control rod, heavy reflector, in-core & out-core experiments…). This paper deals with the works started since 2009 in the Reactor Studies Department of CEA Cadarache in ordre to answer to several problematic which have been identified as well for nuclear data production and calculation as for experimental measurement methods. The selected subjects are: Development of a Monte Carlo code (FIFRELIN) to simulate the prompt fission gamma emission which represents the major part of the gamma heating production inside the core Production and qualification of new evaluations of nuclear data especially for radiative capture and inelastic neutron scattering which are the main sources of gamma heating out-core Development and qualification of a recommended method for the total gamma heating calculation using the Monte Carlo simulation code TRIPOLI-4 Development, test and qualification of new devices dedicated to the in-core gamma heating measurement as well in MTR-JHR as in zero power facilities (EOLE-MINERVE) of CEA, Cadarache to increase the experimental measurement accuracy.

  11. Active space heating and hot water supply with solar energy

    SciTech Connect

    Karaki, S.; Loef, G. O.G.

    1981-04-01

    Technical and economic assessments are given of solar water heaters, both circulating, and of air-based and liquid-based solar space heating systems. Both new and retrofit systems are considered. The technical status of flat-plate and evacuated tube collectors and of thermal storage is also covered. Non-technical factors are also briefly discussed, including the participants in the use of solar heat, incentives and deterrents. Policy implications are considered as regards acceleration of solar use, goals for solar use, means for achieving goals, and interaction of governments, suppliers, and users. Government actions are recommended. (LEW)

  12. Detection of seal contamination in heat-sealed food packaging based on active infrared thermography

    NASA Astrophysics Data System (ADS)

    D'huys, Karlien; Saeys, Wouter; De Ketelaere, Bart

    2015-05-01

    In the food industry packaging is often applied to protect the product from the environment, assuring quality and safety throughout shelf life if properly performed. Packaging quality depends on the material used and the closure (seal). The material is selected based on the specific needs of the food product to be wrapped. However, proper closure of the package is often harder to achieve. One problem possibly jeopardizing seal quality is the presence of food particles between the seal. Seal contamination can cause a decreased seal strength and thus an increased packaging failure risk. It can also trigger the formation of microchannels through which air and microorganisms can enter and spoil the enclosed food. Therefore, early detection and removal of seal-contaminated packages from the production chain is essential. In this work, a pulsed-type active thermography method using the heat of the sealing bars as an excitation source was studied for detecting seal contamination. The cooling profile of contaminated seals was recorded. The detection performance of four processing methods (based on a single frame, a fit of the cooling profile, pulsed phase thermography and a matched filter) was compared. High resolution digital images served as a reference to quantify contamination. The lowest detection limit (equivalent diameter of 0.63 mm) and the lowest processing time (0.42 s per sample) were obtained for the method based on a single frame. Presumably, practical limitations in the recording stage prevented the added value of active thermography to be fully reflected in this application.

  13. Assessment of heat treatment of dairy products by MALDI-TOF-MS.

    PubMed

    Meltretter, Jasmin; Birlouez-Aragon, Inès; Becker, Cord-Michael; Pischetsrieder, Monika

    2009-12-01

    The formation of the Amadori product from lactose (protein lactosylation) is a major parameter to evaluate the quality of processed milk. Here, MALDI-TOF-MS was used for the relative quantification of lactose-adducts in heated milk. Milk was heated at a temperature of 70, 80, and 100 degrees C between 0 and 300 min, diluted, and subjected directly to MALDI-TOF-MS. The lactosylation rate of alpha-lactalbumin increased with increasing reaction temperature and time. The results correlated well with established markers for heat treatment of milk (concentration of total soluble protein, soluble alpha-lactalbumin and beta-lactoglobulin at pH 4.6, and fluorescence of advanced Maillard products and soluble tryptophan index; r=0.969-0.997). The method was also applied to examine commercially available dairy products. In severely heated products, protein pre-purification by immobilized metal affinity chromatography improved spectra quality. Relative quantification of protein lactosylation by MALDI-TOF-MS proved to be a very fast and reliable method to monitor early Maillard reaction during milk processing.

  14. How to estimate the heat production of a 'hidden' reservoir in Earth's mantle

    NASA Astrophysics Data System (ADS)

    Korenaga, J.

    2008-12-01

    The possibility of a hidden geochemical reservoir in the deep mantle has long been debated in geophysics and geochemistry, because of its bearings on the structure of the core-mantle boundary region, the origin of hotspots, the style of mantle convection, the history of the geomagnetic field, and the thermal evolution of Earth. The geochemical nature of a hidden reservoir, however, has been estimated based on composition models for the bulk silicate Earth, although these models preclude, in principle, the presence of such reservoir. Here we present a new self-consistent framework to estimate the neodymium and samarium concentration of a hidden reservoir and also constrain the heat production of the bulk silicate Earth, based on the notion of early global differentiation. Our geochemical inference is formulated as a nonlinear inverse problem, and the permissible solution space, delineated by Markov chain Monte Carlo simulations, indicates that an early enriched reservoir may occupy ~13% of the mantle with internal heat production of ~6~TW. If a hidden reservoir corresponds to the D" layer instead, its heat production would be only ~4~TW. The heat production of the bulk silicate Earth is estimated to be 18.9±3.8~TW, which is virtually independent of the likely reservoir size.

  15. Process for producing an activated carbon adsorbent with integral heat transfer apparatus

    NASA Technical Reports Server (NTRS)

    Jones, Jack A. (Inventor); Yavrouian, Andre H. (Inventor)

    1996-01-01

    A process for producing an integral adsorbent-heat exchanger apparatus useful in ammonia refrigerant heat pump systems. In one embodiment, the process wets an activated carbon particles-solvent mixture with a binder-solvent mixture, presses the binder wetted activated carbon mixture on a metal tube surface and thereafter pyrolyzes the mixture to form a bonded activated carbon matrix adjoined to the tube surface. The integral apparatus can be easily and inexpensively produced by the process in large quantities.

  16. Heat production of quiescent ventricular trabeculae isolated from guinea-pig heart.

    PubMed Central

    Daut, J; Elzinga, G

    1988-01-01

    1. A new calorimetric technique has been developed which allows continuous measurement of the rate of energy expenditure in superfused preparations of cardiac muscle. Thin trabeculae of guinea-pig ventricular muscle were mounted in a Perspex tube of 0.8 mm inner diameter and the temperature difference of the perfusate upstream and downstream of the preparation was measured. 2. The resting heat rate of trabeculae of 240-575 microns diameter from guinea-pig heart was determined repeatedly for up to 6 h after cardiectomy. It did not vary with time during the course of the experiment. 3. The average resting heat rate measured in HEPES-buffered Tyrode solution containing 20 mM-glucose and 2 mM-pyruvate as substrates was 130 +/- 29 mW/g dry weight or 36 +/- 8 mW/cm3 of tissue (n = 15). This is an order of magnitude larger than the resting heat rate reported in the literature for isolated cardiac preparations. 4. After omitting the pyruvate from the superfusate the resting heat rate decreased to 60-70% of its steady value within 4 min. After readmission of pyruvate this effect was reversed. The average resting heat rate with glucose as sole substrate was 23 +/- 4 mW/cm3. 5. Uncoupling of the mitochondria by 50 microM-2,4-dinitrophenol (DNP) increased the heat rate up to 170 mW/cm3. This effect could be maintained for several minutes and was fully reversible. Raising the external K+ concentration to 150 mM (NaCl replaced by KCl) induced a transient rise in the rate of heat production up to 115 mW/cm3. 6. The heat production during uncoupling of the mitochondria and during potassium contractures was inversely related to the diameter of the preparation. Calculation based on Hill's equation (Hill, 1928) indicated that this was caused by the development of anoxia at the core of the preparation. 7. In contrast, the rate of heat production of quiescent preparations was not correlated with diameter and calculation indicated that at rest there was no anoxic core. The high value of

  17. Annual DOE active solar heating and cooling contractors' review meeting. Premeeting proceedings and project summaries

    SciTech Connect

    None,

    1981-09-01

    Ninety-three project summaries are presented which discuss the following aspects of active solar heating and cooling: Rankine solar cooling systems; absorption solar cooling systems; desiccant solar cooling systems; solar heat pump systems; solar hot water systems; special projects (such as the National Solar Data Network, hybrid solar thermal/photovoltaic applications, and heat transfer and water migration in soils); administrative/management support; and solar collector, storage, controls, analysis, and materials technology. (LEW)

  18. Origin, distribution and glaciological implications of Jurassic high heat production granites in the Weddell Sea rift, Antarctica

    NASA Astrophysics Data System (ADS)

    Leat, Phil T.; Jordan, Tom A. R. M.; Ferraccioli, Fausto; Flowerdew, Michael; R, Riley, Teal; Vaughan, Alan P. M.; Whitehouse, Martin

    2013-04-01

    The distribution of heat flow in Antarctic continental crust is critical to understanding ice sheet nucleation, growth and basal rheology and hydrology. We identify a group of High Heat Production granites intruded into Palaeozoic sedimentary sequences which may contribute to locally high heat flow beneath the central part of the West Antarctic Ice Sheet. Four of the granite plutons are exposed above ice sheet level at Pagano Nunatak, Pirrit Hills, Nash Hills and Whitmore Mountains. A new U-Pb zircon age from Pirrit Hills of 177.9 ± 2.3 Ma confirms earlier Rb-Sr dating that suggested an Early-Middle Jurassic age for the granites, coincident with the Karoo-Ferrar large igneous province and the first stage of Gondwana break-up. Our recently-acquired aerogeophysical data indicate that the plutons are distributed unevenly over 1000 km2 and were intruded into the actively extending, locally transcurrent, Jurassic Weddell Sea Rift [1]. In the NW part of the rift, the Pirrit Hills, Nash Hills and Whitmore Mountains granites form small isolated intrusions within weakly deformed upper crust. In the SE part of the rift, where granite intrusion was strongly structurally controlled within transtensional structures, the Pagano Nunatak granite is the only outcrop of a probably multiphase, ca 180 km long granite intrusion. The granites are weakly peraluminous, S-type and have Th and U abundances up to 61 and 19 ppm respectively. Heat production of analysed granite samples is ca. 2.9-9.1 µWm-3, toward the upper limit of values for High Heat Production granites globally. The granites are thought to have been generated during mafic underplating of the Weddell Rift during eruption of the contemporaneous Karoo-Ferrar magmatism [2]. The high Th and U abundances may be related to fractionation of the high Th-U Ferrar basaltic magmas combined with assimilation of pelitic sedimentary rocks. The granites correspond to an area of West Antarctica that may have heat flow significantly above

  19. Experimental evidence in support of Joule heating associated with geomagnetic activity

    NASA Technical Reports Server (NTRS)

    Devries, L. L.

    1971-01-01

    High resolution accelerometer measurements in the altitude region 140 to 300 km from a satellite in a near-polar orbit during a period of extremely high geomagnetic activity indicate that Joule heating is the primary source of energy for atmospheric heating associated with geomagnetic activity. This conclusion is supported by the following observational evidence: (1) There is an atmospheric response in the auroral zone which is nearly simulataneous with the onset of geomagnetic activity, with no significant response in the equatorial region until several hours later; (2) The maximum heating occurs at geographic locations near the maximum current of the auroral electrojet; and (3) There is evidence of atmospheric waves originating near the auroral zone at altitudes where Joule heating would be expected to occur. An analysis of atmospheric response time to this heat shows time delays are apparently independent of altitude but are strongly dependent upon geomagnetic latitude.

  20. Oral immunization of mice with attenuated Salmonella enteritidis containing a recombinant plasmid which codes for production of the B subunit of heat-labile Escherichia coli enterotoxin.

    PubMed Central

    Clements, J D; Lyon, F L; Lowe, K L; Farrand, A L; el-Morshidy, S

    1986-01-01

    We used Salmonella enteritidis serotype dublin strain SL1438, a nonreverting, aromatic-dependent, histidine-requiring mutant, as a recipient for a recombinant plasmid coding for production of the nontoxic B subunit of the heat-labile Escherichia coli enterotoxin. The S. enteritidis derivative EL23 produced heat-labile enterotoxin subunit B that was indistinguishable from heat-labile enterotoxin subunit B produced by strains of E. coli or Salmonella typhi harboring the same plasmid. Mice immunized orally with strain EL23 developed progressively increasing mucosal and serum antibody responses to both heat-labile enterotoxin subunit B and to the lipopolysaccharide of the vaccine strain. The mucosal antibody response was shown to be immunoglobulin A specific and to be capable of neutralizing the biological activities of both E. coli heat-labile enterotoxin and cholera enterotoxin in vitro. Images PMID:3527989

  1. Catalase and superoxide dismutase activities after heat injury of listeria monocytogenes

    SciTech Connect

    Dallmier, A.W.; Martin, S.E.

    1988-02-01

    Four strains of Listeria monocytogenes were examined for catalase (CA) and superoxide dismutase (SOD) activities. The two strains having the highest CA activities (LCDC and Scott A) also possessed the highest SOD activities. The CA activity of heated cell extracts of all four strains examined decreased sharply between 55 and 60/sup 0/C. SOD was more heat labile than CA. Two L. monocytogenes strains demonstrated a decline in SOD activity after heat treatment at 45/sup 0/C, whereas the other two strains demonstrated a decline at 50/sup 0/C. Sublethal heating of the cells at 55/sup 0/C resulted in increased sensitivity to 5.5% NaCl. Exogenous hydrogen peroxide was added to suspensions of L. monocytogenes; strains producing the highest CA levels showed the greatest H/sub 2/O/sub 2/ resistance.

  2. Expression profile of heat shock response factors during hookworm larval activation and parasitic development.

    PubMed

    Gelmedin, Verena; Delaney, Angela; Jennelle, Lucas; Hawdon, John M

    2015-07-01

    When organisms are exposed to an increase in temperature, they undergo a heat shock response (HSR) regulated by the transcription factor heat shock factor 1 (HSF-1). The heat shock response includes the rapid changes in gene expression initiated by binding of HSF-1 to response elements in the promoters of heat shock genes. Heat shock proteins function as molecular chaperones to protect proteins during periods of elevated temperature and other stress. During infection, hookworm infective third stage larvae (L3) undergo a temperature shift from ambient to host temperature. This increased temperature is required for the resumption of feeding and activation of L3, but whether this increase initiates a heat shock response is unknown. To investigate the role of the heat shock in hookworm L3 activation and parasitic development, we identified and characterized the expression profile of several components of the heat shock response in the hookworm Ancylostoma caninum. We cloned DNAs encoding an hsp70 family member (Aca-hsp-1) and an hsp90 family member (Aca-daf-21). Exposure to a heat shock of 42°C for one hour caused significant up-regulation of both genes, which slowly returned to near baseline levels following one hour attenuation at 22°C. Neither gene was up-regulated in response to host temperature (37°C). Conversely, levels of hsf-1 remained unchanged during heat shock, but increased in response to incubation at 37°C. During activation, both hsp-1 and daf-21 are down regulated early, although daf-21 levels increase significantly in non-activated control larvae after 12h, and slightly in activated larvae by 24h incubation. The heat shock response modulators celastrol and KNK437 were tested for their effects on gene expression during heat shock and activation. Pre-incubation with celastrol, an HSP90 inhibitor that promotes heat shock gene expression, slightly up-regulated expression of both hsp-1 and daf-21 during heat shock. KNK437, an inhibitor of heat shock

  3. Joule-Heated Molten Regolith Electrolysis Reactor Concepts for Oxygen and Metals Production on the Moon and Mars

    NASA Technical Reports Server (NTRS)

    Sibille, Laurent; Dominques, Jesus A.

    2012-01-01

    The maturation of Molten Regolith Electrolysis (MRE) as a viable technology for oxygen and metals production on explored planets relies on the realization of the self-heating mode for the reactor. Joule heat generated during regolith electrolysis creates thermal energy that should be able to maintain the molten phase (similar to electrolytic Hall-Heroult process for aluminum production). Self-heating via Joule heating offers many advantages: (1) The regolith itself is the crucible material, it protects the vessel walls (2) Simplifies the engineering of the reactor (3) Reduces power consumption (no external heating) (4) Extends the longevity of the reactor. Predictive modeling is a tool chosen to perform dimensional analysis of a self-heating reactor: (1) Multiphysics modeling (COMSOL) was selected for Joule heat generation and heat transfer (2) Objective is to identify critical dimensions for first reactor prototype.

  4. Production of high specific activity silicon-32

    DOEpatents

    Phillips, Dennis R.; Brzezinski, Mark A.

    1994-01-01

    A process for preparation of silicon-32 is provide and includes contacting an irradiated potassium chloride target, including spallation products from a prior irradiation, with sufficient water, hydrochloric acid or potassium hydroxide to form a solution, filtering the solution, adjusting pH of the solution to from about 5.5 to about 7.5, admixing sufficient molybdate-reagent to the solution to adjust the pH of the solution to about 1.5 and to form a silicon-molybdate complex, contacting the solution including the silicon-molybdate complex with a dextran-based material, washing the dextran-based material to remove residual contaminants such as sodium-22, separating the silicon-molybdate complex from the dextran-based material as another solution, adding sufficient hydrochloric acid and hydrogen peroxide to the solution to prevent reformation of the silicon-molybdate complex and to yield an oxidization state of the molybdate adapted for subsequent separation by an anion exchange material, contacting the solution with an anion exchange material whereby the molybdate is retained by the anion exchange material and the silicon remains in solution, and optionally adding sufficient alkali metal hydroxide to adjust the pH of the solution to about 12 to 13. Additionally, a high specific activity silicon-32 product having a high purity is provided.

  5. Monascus secondary metabolites: production and biological activity.

    PubMed

    Patakova, Petra

    2013-02-01

    The genus Monascus, comprising nine species, can reproduce either vegetatively with filaments and conidia or sexually by the formation of ascospores. The most well-known species of genus Monascus, namely, M. purpureus, M. ruber and M. pilosus, are often used for rice fermentation to produce red yeast rice, a special product used either for food coloring or as a food supplement with positive effects on human health. The colored appearance (red, orange or yellow) of Monascus-fermented substrates is produced by a mixture of oligoketide pigments that are synthesized by a combination of polyketide and fatty acid synthases. The major pigments consist of pairs of yellow (ankaflavin and monascin), orange (rubropunctatin and monascorubrin) and red (rubropunctamine and monascorubramine) compounds; however, more than 20 other colored products have recently been isolated from fermented rice or culture media. In addition to pigments, a group of monacolin substances and the mycotoxin citrinin can be produced by Monascus. Various non-specific biological activities (antimicrobial, antitumor, immunomodulative and others) of these pigmented compounds are, at least partly, ascribed to their reaction with amino group-containing compounds, i.e. amino acids, proteins or nucleic acids. Monacolins, in the form of β-hydroxy acids, inhibit hydroxymethylglutaryl-coenzyme A reductase, a key enzyme in cholesterol biosynthesis in animals and humans.

  6. Repairing Student Misconceptions in Heat Transfer Using Inquiry-Based Activities

    ERIC Educational Resources Information Center

    Prince, Michael; Vigeant, Margot; Nottis, Katharyn

    2016-01-01

    Eight inquiry-based activities, described here in sufficient detail for faculty to adopt in their own courses, were designed to teach students fundamental concepts in heat transfer. The concept areas chosen were (1) factors affecting the rate vs. amount of heat transfer, (2) temperature vs. perceptions of hot and cold, (3) temperature vs. energy…

  7. Modeling the Daly Gap: The Influence of Latent Heat Production in Controlling Magma Extraction and Eruption

    NASA Astrophysics Data System (ADS)

    Nelson, B. K.; Ghiorso, M. S.; Bachmann, O.; Dufek, J.

    2011-12-01

    A century-old issue in volcanology is the origin of the gap in chemical compositions observed in magmatic series on ocean islands and arcs - the "Daly Gap". If the gap forms during differentiation from a mafic parent, models that predict the dynamics of magma extraction as a function of chemical composition must simulate a process that results in volumetrically biased, bimodal compositions of erupted magmas. The probability of magma extraction is controlled by magma dynamical processes, which have a complex response to magmatic heat evolution. Heat loss from the magmatic system is far from a simple, monotonic function of time. It is modified by the crystallization sequence, chamber margin heat flux, and is buffered by latent heat production. We use chemical and thermal calculations of MELTS (Ghiorso & Sack, 1995) as input to the physical model of QUANTUM (Dufek & Bachmann, 2010) to predict crystallinity windows of most probable magma extraction. We modeled two case studies: volcanism on Tenerife, Canary Islands, and the Campanian Ignimbrite (CI) of Campi Flegrei, Italy. Both preserve a basanitic to phonolitic lineage and have comparable total alkali concentrations; however, CI has high and Tenerife has low K2O/Na2O. Modeled thermal histories of differentiation for the two sequences contrast strongly. In Tenerife, the rate of latent heat production is almost always greater than sensible heat production, with spikes in the ratio of latent to sensible heats of up to 40 associated with the appearance of Fe-Ti oxides at near 50% crystallization. This punctuated heat production must cause magma temperature change to stall or slow in time. The extended time spent at ≈50% crystallinity, associated with dynamical processes that enhance melt extraction near 50% crystallinity, suggests the magma composition at this interval should be common. In Tenerife, the modeled composition coincides with that of the first peak in the bimodal frequency-composition distribution. In our

  8. Hydrogen production by anaerobic microbial communities exposed to repeated heat treatments.

    PubMed

    Duangmanee, T; Padmasiri, S I; Simmons, J J; Raskin, L; Sung, S

    2007-09-01

    Biological hydrogen production by anaerobic mixed communities was studied in laboratory-scale bioreactors using sucrose as the substrate. A bioreactor in which a fraction of the return sludge was exposed to repeated heat treatments performed better than a control bioreactor without repeated heat treatment of return sludge and produced a yield of 2.15 moles of hydrogen per mole of sucrose, with 50% hydrogen in the biogas. Terminal restriction fragment length polymorphism analysis showed that two different Clostridium groups (comprised of one or more species) were dominant during hydrogen production. The relative abundance of two other non-Clostridium groups increased during periods of decreased hydrogen production. The first group consisted of Bifidobacterium thermophilum, and the second group included one or more of Bacillus, Melissococcus, Spirochaeta, and Spiroplasma spp.

  9. Force-dependent and force-independent heat production in single slow- and fast-twitch muscle fibres from Xenopus laevis.

    PubMed Central

    Buschman, H P; van der Laarse, W J; Stienen, G J; Elzinga, G

    1996-01-01

    1. The origin of labile heat production, i.e. a heat component which rapidly decays after the onset of stimulation, and of stable (maintenance) heat production was investigated in intact single fast-twitch (type 1) and slow-twitch (type 3) iliofibularis muscle fibres from Xenopus laevis, at 20 degrees C, by varying stimulation frequency and by varying sarcomere length and the concentration of 2,3-butanedione 2-monoxime (BDM) added. 2. The labile heat produced consisted of a force-independent and a force-dependent part. The average parvalbumin (PA) content found in type 1 fibre bundles (0.84 +/- 0.08 mM; mean +/- S.E.M.; n = 5) and in type 3 fibre bundles (0.12 +/- 0.02 mM; n = 5) indicates that the force-independent labile heat is explained by Ca(2+)-Mg2+ exchange on PA, and amounts to a molar enthalpy change of -78 kJ (molPA)-1. 3. Force-dependent labile heat during fused contractions was similar to the calculated heat production resulting from the formation of force-generating cross-bridges, assuming an enthalpy change associated with cross-bridge formation of -30 kJ mol-1. 4. Activation heat, i.e. the part of the total stable heat that is not related to the contractile apparatus, and of which the calcium sequestration by the sarcoplasmic reticulum is the most important contributor, determined by varying sarcomere length or BDM concentration, was identical. For fused contractions the fraction activation heat of the stable maintenance rate of heat production was 34 +/- 4% (mean +/- S.E.M.; n = 13) in type 1 fibres, and 52 +/- 4% (n = 15) in type 3 fibres. In unfused contractions this was 48 +/- 5% (n = 13) in type 1 fibres, and 35 +/- 2% (n = 11) in type 3 fibres. 5. From the force-dependent stable rate of heat production the economy of cross-bridge cycling, expressed as the force-time integral for a single myosin head per ATP molecule hydrolysed, was calculated. It followed that cross-bridge interaction in type 3 fibres is more economical than in type 1 fibres

  10. Heat of Combustion of the Product Formed by the Reaction of Acetylene, Ethylene, and Diborane

    NASA Technical Reports Server (NTRS)

    Tannenbaum, Stanley

    1957-01-01

    The net heat of combustion of the product formed by the reaction of diborane with a mixture of acetylene and ethylene was found to be 20,440 +/- 150 Btu per pound for the reaction of liquid fuel to gaseous carbon dioxide, gaseous water, and solid boric oxide. The measurements were made in a Parr oxygen-bomb calorimeter, and the combustion was believed to be 98 percent complete. The estimated net-heat of combustion for complete combustion would therefore be 20,850 +/- 150 Btu per pound.

  11. Optimization of a Mu2e production solenoid heat and radiation shield using MARS15

    SciTech Connect

    Pronskikh, V.S.; Mokhov, N.V.; /Fermilab

    2011-02-01

    A Monte-Carlo study of several Mu2e Production Solenoid (PS) absorber (heat shield) versions using the MARS15 code has been performed. Optimizations for material as well as cost (amount of tungsten) have been carried out. Studied are such quantities as the number of displacements per atom (DPA) in the helium-cooled solenoid superconducting coils, power density and dynamic heat load in various parts of the PS and its surrounding structures. Prompt dose, residual dose, secondary particle flux are also simulated in the PS structures and the experimental hall. A preliminary choice of the PS absorber design is made on the ground of these studies.

  12. Selected demonstration and educational products/activities

    SciTech Connect

    Williams, R.J.; Mann, H.C.

    1992-07-01

    The information in this paper was assembled for several informal presentations to a variety of visitor groups during the summer of 1992. A number of staff members at TVA`s National Fertilizer and Environmental Research Center (NFERC) found it useful as a quick overview for their use and for their sharing with external colleagues and customers. The paper is not meant to be an exhaustive list or explanation of all products and services available from NFERC. However, the authors believe it will give a flavor and tenor of some of the ongoing activities of the Center, especially those activities relating to the retail fertilizer dealer. Programs over the years have focused on key aspects of nutrient efficiency and management. TVA is uniquely positioned to assist the fertilizer industry and US agriculture in protecting the environment from potential adverse environmental impacts of agriculture, especially for fertilizer and the attendant agrichemicals. TVA has the technical base and an ongoing working relationship with the fertilizer industry in technology development and introduction. Dealer education is very important in TVA programs in two aspects: (1) education for the dealer in meeting new environmental stewardship challenges from an operational perspective; and (2) education for the dealer in meeting the site-specific information needs of the farmer.

  13. Integrated bioenergy complex for the production of power, heat and bio-ethanol

    SciTech Connect

    Taviani, M.; Chiaramonti, D.; Tondi, G.; Grassi, G.

    1998-07-01

    In this paper an integrated bioenergy complex for the production of power, heat and bio-ethanol is presented. Ethanol, in fact, has been recognized as a high-quality transportation fuel. The reduction of petroleum consumption, especially for transport, is a strategic goal especially for those countries that already have or will experience an intensive industrial development in the next future. For these motivations, the production of bio-ethanol from Sweet Sorghum (which is now one of the most promising crop for this application in term of productivity, inputs demand, and flexibility) is of great interest in most of countries. The proposed integrated complex produces power, heat and bio-ethanol: the produced power and heat are partly used for bio-ethanol processing and biomass pre-treatment, partly to be sold to the market. This system has important innovations allowing a decentralized energy and ethanol production and creating new local jobs. The small power plant is based upon a steam cycle with an advanced low emission combustor, capable of burning different biomass resources with a modest decrease in the efficiency value. The Bioenergy Complex, suitable to satisfy the needs of a 3,000 inhabitants village, is composed by the following sub-systems: (1) Sweet Sorghum plantation (250 ha); the main products are: dry bagasse (approximately 3,900 Ton/year), grains (1,300 Ton/y) and sugar (1,850 Ton/y); (2) Cane crushing--sugar juice extraction system; (3) Sugar juice fermentation and distillation ethanol production (approx. 835 Ton/y); (4) Biomass pre-treatment components (grinding, drying, briquetting, storage, etc.); and (5) Cogeneration unit--the expansion unit is constituted by a last generation reciprocating steam engine, coupled with a 500 kWe alternator; the heat of the expanded flow is removed in the condenser, with an available thermal power of approximately 2,000 kWt.

  14. Relationship of thermal status to productivity in heat-stressed dairy cows given recombinant bovine somatotropin.

    PubMed

    Settivari, R S; Spain, J N; Ellersieck, M R; Byatt, J C; Collier, R J; Spiers, D E

    2007-03-01

    The responses of lactating Holstein cows to daily administration of bovine somatotropin (bST) were measured at thermoneutrality (Tn) and under both constant and cycled heat-stress conditions to determine the relationship between thermal status and bST-induced shifts in milk production. All tests included a 5-d acclimation period at Tn (18 degrees C), followed by a 2-d increase in ambient temperature to 28.5 degrees C. After d 3, ambient temperature was cycled between 28.5 (day) and 25.5 degrees C (night) for 4 d. Daily injections with either 31 mg of bST or saline began on d 1 of the experiment. Milk production, feed intake, and respiratory rate (RR) were measured daily. Intraperitoneal, telemetric temperature transmitters were used for a continuous measure of core body temperature (T(core)). Blood samples were collected during each phase to evaluate the changes in serum chemistry in response to bST and heat stress. Following a 15-d recovery, cows were switched across injection treatments and the study was repeated. Milk production decreased by approximately 18.4% below the initial yield at Tn by the end of 7 d of heat challenge. Although a reduction in milk production occurred during heat stress in both groups, milk production was higher in bST-treated cows compared with control cows during periods of constant and cyclic heat. Likewise, bST treatment during the entire period increased the milk-to-feed ratio over the control level by approximately 11.3%. Plasma insulin-like growth factor 1 and serum nonesterified fatty acids accompanied the increased growth hormone level with bST treatment (approximately 122.0 and 88.8%, respectively), whereas plasma urea nitrogen was reduced by approximately 13.3% to reflect the shift to lipid metabolism. There was no difference in T(core) of the treatment and control groups at Tn. Both bST and control cows increased RR and T(core) above the Tn level by approximately 94.8 and 2.9%, respectively, during constant heat, with a

  15. Heat-resistance of Hamigera avellanea and Thermoascus crustaceus isolated from pasteurized acid products.

    PubMed

    Scaramuzza, Nicoletta; Berni, Elettra

    2014-01-01

    Products containing sugar or fruit derivatives are usually subjected to a pasteurization process that can anyway be ineffective to kill ascospores from heat-resistant molds. Although the most occurring and economically relevant heat-resistant species belong to Byssochlamys, Neosartorya, Talaromyces, and Eupenicillium genera, an increasing number of uncommon heat-resistant isolates have been recently detected as spoiling microorganisms in such products. Since Hamigera spp. and Thermoascus spp. were those more frequently isolated at SSICA, heat resistance of Hamigera avellanea and Thermoascus crustaceus strains from pasteurized acid products was studied in apple juice, in blueberry and grape juice and in a buffered glucose solution. Data obtained from thermal death curves and statistical elaboration of raw data showed that D values of H. avellanea may vary between 11.11 and 66.67 min at 87°C, between 4.67 and 13.51 at 90°C, and between 0.43 and 1.52 min at 95°C. Similarly, D values of T. crustaceus may vary between 18.52 and 90.91 min at 90°C, between 2.79 and 19.23 at 93°C, and between 1.11 and 2.53 min at 95°C. For both strains studied, the z-values calculated from the decimal reduction time curves did not prove to be significantly influenced by the heating medium, that being 4.35°C, 5.39°C or 5.27°C for H. avellanea and 4.42°C, 3.69°C or 3.37°C for T. crustaceus, respectively in apple juice, in blueberry and grape juice or in the buffered glucose solution. Considering the pasteurization treatments industrially applied to fruit-based foods, the variation of thermal parameters does not seem to be a possible way to avoid product spoilage by these two species and only good practices applied to reduce the original load of heat-resistant fungi can help producers to prevent losses in contaminated finished products, as usually happens for other heat resistant molds.

  16. Effect of heat treatment on the antioxidant activity of extracts from citrus peels.

    PubMed

    Jeong, Seok-Moon; Kim, So-Young; Kim, Dong-Ryul; Jo, Seong-Chun; Nam, K C; Ahn, D U; Lee, Seung-Cheol

    2004-06-01

    The effect of heat treatment on the antioxidant activity of extracts from Citrus unshiu peels was evaluated. Citrus peels (CP) (5 g) were placed in Pyrex Petri dishes (8.0 cm diameter) and heat-treated at 50, 100, or 150 degrees C for 10, 20, 30, 40, 50, and 60 min in an electric muffle furnace. After heat treatment, 70% ethanol extract (EE) and water extract (WE) (0.1 g/10 mL) of CP were prepared, and total phenol contents (TPC), radical scavenging activity (RSA), and reducing power of the extracts were determined. The antioxidant activities of CP extracts increased as heating temperature increased. For example, heat treatment of CP at 150 degrees C for 60 min increased the TPC, RSA, and reducing power of EE from 71.8 to 171.0 microM, from 29.64 to 64.25%, and from 0.45 to 0.82, respectively, compared to non-heat-treated control. In the case of WE from CP heat-treated at the same conditions (150 degrees C for 60 min), the TPC, RSA, and reducing power also increased from 84.4 to 204.9 microM, from 15.81 to 58.26%, and from 0.27 to 0.96, respectively. Several low molecular weight phenolic compounds such as 2,3-diacetyl-1-phenylnaphthalene, ferulic acid, p-hydroxybenzaldoxime, 5-hydroxyvaleric acid, 2,3-diacetyl-1-phenylnaphthalene, and vanillic acid were newly formed in the CP heated at 150 degrees C for 30 min. These results indicated that the antioxidant activity of CP extracts was significantly affected by heating temperature and duration of treatment on CP and that the heating process can be used as a tool for increasing the antioxidant activity of CP. PMID:15161203

  17. A tomato chloroplast-targeted DnaJ protein protects Rubisco activity under heat stress.

    PubMed

    Wang, Guodong; Kong, Fanying; Zhang, Song; Meng, Xia; Wang, Yong; Meng, Qingwei

    2015-06-01

    Photosynthesis is one of the biological processes most sensitive to heat stress in plants. Carbon assimilation, which depends on ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco), is one of the major sites sensitive to heat stress in photosynthesis. In this study, the roles of a tomato (Solanum lycopersicum) chloroplast-targeted DnaJ protein (SlCDJ2) in resisting heat using sense and antisense transgenic tomatoes were examined. SlCDJ2 was found to be uniformly distributed in the thylakoids and stroma of the chloroplasts. Under heat stress, sense plants exhibited higher chlorophyll contents and fresh weights, and lower accumulation of reactive oxygen species (ROS) and membrane damage. Moreover, Rubisco activity, Rubisco large subunit (RbcL) content, and CO2 assimilation capacity were all higher in sense plants and lower in antisense plants compared with wild-type plants. Thus, SlCDJ2 contributes to maintenance of CO2 assimilation capacity mainly by protecting Rubisco activity under heat stress. SlCDJ2 probably achieves this by keeping the levels of proteolytic enzymes low, which prevents accelerated degradation of Rubisco under heat stress. Furthermore, a chloroplast heat-shock protein 70 was identified as a binding partner of SlCDJ2 in yeast two-hybrid assays. Taken together, these findings establish a role for SlCDJ2 in maintaining Rubisco activity in plants under heat stress. PMID:25801077

  18. A tomato chloroplast-targeted DnaJ protein protects Rubisco activity under heat stress.

    PubMed

    Wang, Guodong; Kong, Fanying; Zhang, Song; Meng, Xia; Wang, Yong; Meng, Qingwei

    2015-06-01

    Photosynthesis is one of the biological processes most sensitive to heat stress in plants. Carbon assimilation, which depends on ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco), is one of the major sites sensitive to heat stress in photosynthesis. In this study, the roles of a tomato (Solanum lycopersicum) chloroplast-targeted DnaJ protein (SlCDJ2) in resisting heat using sense and antisense transgenic tomatoes were examined. SlCDJ2 was found to be uniformly distributed in the thylakoids and stroma of the chloroplasts. Under heat stress, sense plants exhibited higher chlorophyll contents and fresh weights, and lower accumulation of reactive oxygen species (ROS) and membrane damage. Moreover, Rubisco activity, Rubisco large subunit (RbcL) content, and CO2 assimilation capacity were all higher in sense plants and lower in antisense plants compared with wild-type plants. Thus, SlCDJ2 contributes to maintenance of CO2 assimilation capacity mainly by protecting Rubisco activity under heat stress. SlCDJ2 probably achieves this by keeping the levels of proteolytic enzymes low, which prevents accelerated degradation of Rubisco under heat stress. Furthermore, a chloroplast heat-shock protein 70 was identified as a binding partner of SlCDJ2 in yeast two-hybrid assays. Taken together, these findings establish a role for SlCDJ2 in maintaining Rubisco activity in plants under heat stress.

  19. The temperature response of CO2 assimilation, photochemical activities and Rubisco activation in Camelina sativa, a potential bioenergy crop with limited capacity for acclimation to heat stress.

    PubMed

    Carmo-Silva, A Elizabete; Salvucci, Michael E

    2012-11-01

    The temperature optimum of photosynthesis coincides with the average daytime temperature in a species' native environment. Moderate heat stress occurs when temperatures exceed the optimum, inhibiting photosynthesis and decreasing productivity. In the present study, the temperature response of photosynthesis and the potential for heat acclimation was evaluated for Camelina sativa, a bioenergy crop. The temperature optimum of net CO(2) assimilation rate (A) under atmospheric conditions was 30-32 °C and was only slightly higher under non-photorespiratory conditions. The activation state of Rubisco was closely correlated with A at supra-optimal temperatures, exhibiting a parallel decrease with increasing leaf temperature. At both control and elevated temperatures, the modeled response of A to intercellular CO(2) concentration was consistent with Rubisco limiting A at ambient CO(2). Rubisco activation and photochemical activities were affected by moderate heat stress at lower temperatures in camelina than in the warm-adapted species cotton and tobacco. Growth under conditions that imposed a daily interval of moderate heat stress caused a 63 % reduction in camelina seed yield. Levels of cpn60 protein were elevated under the higher growth temperature, but acclimation of photosynthesis was minimal. Inactivation of Rubisco in camelina at temperatures above 35 °C was consistent with the temperature response of Rubisco activase activity and indicated that Rubisco activase was a prime target of inhibition by moderate heat stress in camelina. That photosynthesis exhibited no acclimation to moderate heat stress will likely impact the development of camelina and other cool season Brassicaceae as sources of bioenergy in a warmer world.

  20. Heat production and error probability relation in Landauer reset at effective temperature

    PubMed Central

    Neri, Igor; López-Suárez, Miquel

    2016-01-01

    The erasure of a classical bit of information is a dissipative process. The minimum heat produced during this operation has been theorized by Rolf Landauer in 1961 to be equal to kBT ln2 and takes the name of Landauer limit, Landauer reset or Landauer principle. Despite its fundamental importance, the Landauer limit remained untested experimentally for more than fifty years until recently when it has been tested using colloidal particles and magnetic dots. Experimental measurements on different devices, like micro-mechanical systems or nano-electronic devices are still missing. Here we show the results obtained in performing the Landauer reset operation in a micro-mechanical system, operated at an effective temperature. The measured heat exchange is in accordance with the theory reaching values close to the expected limit. The data obtained for the heat production is then correlated to the probability of error in accomplishing the reset operation. PMID:27669898

  1. Heat production and error probability relation in Landauer reset at effective temperature

    NASA Astrophysics Data System (ADS)

    Neri, Igor; López-Suárez, Miquel

    2016-09-01

    The erasure of a classical bit of information is a dissipative process. The minimum heat produced during this operation has been theorized by Rolf Landauer in 1961 to be equal to kBT ln2 and takes the name of Landauer limit, Landauer reset or Landauer principle. Despite its fundamental importance, the Landauer limit remained untested experimentally for more than fifty years until recently when it has been tested using colloidal particles and magnetic dots. Experimental measurements on different devices, like micro-mechanical systems or nano-electronic devices are still missing. Here we show the results obtained in performing the Landauer reset operation in a micro-mechanical system, operated at an effective temperature. The measured heat exchange is in accordance with the theory reaching values close to the expected limit. The data obtained for the heat production is then correlated to the probability of error in accomplishing the reset operation.

  2. PCR-SSCP-based reconstruction of the original fungal flora of heat-processed meat products.

    PubMed

    Dorn-In, Samart; Hölzel, Christina S; Janke, Tobias; Schwaiger, Karin; Balsliemke, Joachim; Bauer, Johann

    2013-03-01

    Food processing of spoiled meat is prohibited by law, since it is a deception and does not comply with food safety aspects. In general, spoilage of meat is mostly caused by bacteria. However, a high contamination level of fungi could be also found in some meat or meat products with certain preserving conditions. In case that unhygienic meat is used to produce heat processed products, the microorganisms will be deactivated by heat, so that they cannot be detected by a standard cultivation method. Therefore, this study aimed to develop and apply a molecular biological method--polymerase chain reaction and single strand conformation polymorphism (PCR-SSCP)--to reconstruct the original fungal flora of heat processed meat. Twenty primer pairs were tested for their specificity for fungal DNA. Since none of them fully complied with all study criteria (such as high specificity and sensitivity for fungal DNA; suitability of the products for PCR-SSCP) in the matrix "meat", we designed a new reverse primer, ITS5.8R. The primer pair ITS1/ITS5.8R amplified DNA from all tested fungal species, but not DNA from meat-producing animals or from ingredients of plant origin (spices). For the final test, 32 DNA bands in acrylamide gel from 15 meat products and 1 soy sauce were sequenced-all originating from fungal species, which were, in other studies, reported to contaminate meat e.g. Alternaria alternata, Aureobasidium pullulans, Candida rugosa, C. tropicalis, C. zeylanoides, Eurotium amstelodami and Pichia membranifaciens, and/or spices such as Botrytis aclada, Guignardia mangiferae, Itersonilia perplexans, Lasiodiplodia theobromae, Lewia infectoria, Neofusicoccum parvum and Pleospora herbarum. This confirms the suitability of PCR-SSCP to specifically detect fungal DNA in heat processed meat products, and thus provides an overview of fungal species contaminating raw material such as meat and spices. PMID:23361099

  3. Dissipated energy and entropy production for an unconventional heat engine: the stepwise `circular cycle'

    NASA Astrophysics Data System (ADS)

    di Liberto, Francesco; Pastore, Raffaele; Peruggi, Fulvio

    2011-05-01

    When some entropy is transferred, by means of a reversible engine, from a hot heat source to a colder one, the maximum efficiency occurs, i.e. the maximum available work is obtained. Similarly, a reversible heat pumps transfer entropy from a cold heat source to a hotter one with the minimum expense of energy. In contrast, if we are faced with non-reversible devices, there is some lost work for heat engines, and some extra work for heat pumps. These quantities are both related to entropy production. The lost work, i.e. ? , is also called 'degraded energy' or 'energy unavailable to do work'. The extra work, i.e. ? , is the excess of work performed on the system in the irreversible process with respect to the reversible one (or the excess of heat given to the hotter source in the irreversible process). Both quantities are analysed in detail and are evaluated for a complex process, i.e. the stepwise circular cycle, which is similar to the stepwise Carnot cycle. The stepwise circular cycle is a cycle performed by means of N small weights, dw, which are first added and then removed from the piston of the vessel containing the gas or vice versa. The work performed by the gas can be found as the increase of the potential energy of the dw's. Each single dw is identified and its increase, i.e. its increase in potential energy, evaluated. In such a way it is found how the energy output of the cycle is distributed among the dw's. The size of the dw's affects entropy production and therefore the lost and extra work. The distribution of increases depends on the chosen removal process.

  4. Development of Naphthalene PLIF for Visualizing Ablation Products From a Space Capsule Heat Shield

    NASA Technical Reports Server (NTRS)

    Combs, C. S.; Clemens, N. T.; Danehy, P. M.

    2014-01-01

    The Orion Multi-Purpose Crew Vehicle (MPCV) will use an ablative heat shield. To better design this heat shield and others that will undergo planetary entry, an improved understanding of the ablation process would be beneficial. Here, a technique developed at The University of Texas at Austin that uses planar laser-induced fluorescence (PLIF) of a low-temperature sublimating ablator (naphthalene) to enable visualization of the ablation products in a hypersonic flow is applied. Although high-temperature ablation is difficult and expensive to recreate in a laboratory environment, low-temperature sublimation creates a limited physics problem that can be used to explore ablation-product transport in a hypersonic flow-field. In the current work, a subscale capsule reentry vehicle model with a solid naphthalene heat shield has been tested in a Mach 5 wind tunnel. The PLIF technique provides images of the spatial distribution of sublimated naphthalene in the heat-shield boundary layer, separated shear layer, and backshell recirculation region. Visualizations of the capsule shear layer using both naphthalene PLIF and Schlieren imaging compared favorably. PLIF images have shown high concentrations of naphthalene in the capsule separated flow region, intermittent turbulent structures on the heat shield surface, and interesting details of the capsule shear layer structure. It was shown that, in general, the capsule shear layer appears to be more unsteady at lower angels of attack. The PLIF images demonstrated that during a wind tunnel run, as the model heated up, the rate of naphthalene ablation increased, since the PLIF signal increased steadily over the course of a run. Additionally, the shear layer became increasingly unsteady over the course of a wind tunnel run, likely because of increased surface roughness but also possibly because of the increased blowing. Regions with a relatively low concentration of naphthalene were also identified in the capsule backshell

  5. The effect of mechanical activation on the heat capacity of powdered tungsten

    NASA Astrophysics Data System (ADS)

    Malkin, A. I.; Kiselev, M. R.; Klyuev, V. A.; Loznetsova, N. N.; Toporov, Yu. P.

    2012-06-01

    We have studied the heat capacity ( C p ) of a mechanically activated tungsten powder. It is established that the mechanical processing leads to an increase in C p of the metal powder at low temperatures and modifies the character of the temperature dependence of this parameter. The dependences of C p and its heating-induced variation on the treatment duration have been determined. It is concluded that the observed effects are related to the accumulation of defects in the metal grain volume during mechanical activation and their annealing in the course of heating.

  6. Effect of Sodium Carboxymethyl Celluloses on Water-catalyzed Self-degradation of 200-degree C-heated Alkali-Activated Cement

    SciTech Connect

    Sugama T.; Pyatina, T.

    2012-05-01

    We investigated the usefulness of sodium carboxymethyl celluloses (CMC) in promoting self-degradation of 200°C-heated sodium silicate-activated slag/Class C fly ash cementitious material after contact with water. CMC emitted two major volatile compounds, CO2 and acetic acid, creating a porous structure in cement. CMC also reacted with NaOH from sodium silicate to form three water-insensitive solid reaction products, disodium glycolate salt, sodium glucosidic salt, and sodium bicarbonate. Other water-sensitive solid reaction products, such as sodium polysilicate and sodium carbonate, were derived from hydrolysates of sodium silicate. Dissolution of these products upon contact with water generated heat that promoted cement’s self-degradation. Thus, CMC of high molecular weight rendered two important features to the water-catalyzed self-degradation of heated cement: One was the high heat energy generated in exothermic reactions in cement; the other was the introduction of extensive porosity into cement.

  7. Role of HSF activation for resistance to heat, cold and high-temperature knock-down.

    PubMed

    Nielsen, Morten Muhlig; Overgaard, Johannes; Sørensen, Jesper Givskov; Holmstrup, Martin; Justesen, Just; Loeschcke, Volker

    2005-12-01

    Regulation of heat shock proteins (Hsps) by the heat shock factor (HSF) and the importance of these proteins for resistance to heat stress is well documented. Less characterized is the importance of Hsps for cold stress resistance although Hsp70 is known to be induced following long-term cold exposure in Drosophila melanogaster. In this study, a temperature-sensitive HSF mutant line was used to investigate the role of HSF activation following heat hardening, rapid cold hardening (RCH) and long-term cold acclimation (LTCA) on heat and cold resistance, and this was correlated with Hsp70 expression. In addition, the effect of HSF activation on high-temperature knock-down resistance was evaluated. We found a significantly decreased HSF activation in the mutant line as compared to a corresponding control line following heat hardening, and this was correlated with decreased heat resistance of the mutant line. However, we did not find this difference in HSF activity to be important for resistance to cold stress or high-temperature knock-down. The findings indicate that induction of stress genes regulated by HSF, such as Hsps, although occurring following LTCA, are not of major importance for cold stress resistance and neither for RCH nor high-temperature knock-down resistance in D. melanogaster. PMID:16169555

  8. Analytical calculation of the skin temperature distribution due to subcutaneous heat production in a spherical heat source.

    PubMed

    Gustafsson, S E; Nilsson, S K; Torell, L M

    1975-03-01

    An analytical solution of the thermal conductivity equation describing the surface temperature distribution over a buried heat source is given in tabular form. The solution is applicable to experimental models for studies of the surface temperature over an implanted artificial heat source. The results can also be used for the analysis of the skin temperature over biological heat sources such as breat tumours.

  9. Subtask 12A1: Fabrication of production-scale heat of V-4Cr-4Ti

    SciTech Connect

    Chung, H.M.; Tsai, H.C.; Smith, D.L.

    1995-03-01

    On the basis of excellent properties that were determined for a laboratory-scale heat, V-4Cr-4Ti has been identified previously as the most promising vanadium-based candidate alloy for application in fusion reactor structural components. The objective of this work is to produce a large-scale (500-kg) ingot of the alloy and fabricate various plates and sheets from the ingot, thereby demonstrating a reliable method of fabricating an industrial-scale heat of V-4Cr-4Ti that exhibits excellent properties. A 500-kg heat of V-4Cr-4Ti, an alloy identified previously as the most promising vanadium-based candidate alloy for application in fusion reactor structural components, has been produced. The ingot was produced by multiple vacuum-arc melting using screened high-quality raw materials of vanadium, chrome, and titanium. Several long bars {approx}64 mm in thickness and {approx}200 mm in width were extruded from the ingot, and plates and sheets of various thicknesses ranging from 1.0 to 29.2 mm were fabricated successfully from the extruded bars. The chemical composition of the ingot and the secondary fabrication procedures, specified on the basis of the experience and knowledge gained from fabrication, testing, and microstructural characterization of a laboratory-scale heat, were found to be satisfactory. Charpy-impact tests showed that mechanical properties of the production-scale heat are as good as those of the laboratory-scale heat. This demonstrates a method of reliable fabrication of industrial-scale heats of V-4Cr-4Ti that exhibit excellent properties. 14 refs., 1 fig., 1 tab.

  10. Measurements of bremsstrahlung production and x-ray cryostat heating in VENUS

    SciTech Connect

    Lyneis, C.; Leitner, D.; Todd, D.; Virostek, S.; Loew, T.; Heinen, A.; Tarvainen, O.

    2006-03-15

    The VENUS superconducting electron cyclotron resonance (ECR) ion source is designed to operate at 28 GHz with up to 10 kW of rf power. Most of this power is absorbed by the plasma electrons and then dumped onto the plasma chamber wall. The distribution of heating and bremsstrahlung production is highly nonuniform and reflects the geometry of the magnetic confinement fields. The nonuniform distribution of electron losses to the wall results in localized heating on the aluminum chamber walls, which can lead to burnout. In addition, part of the bremsstrahlung produced by the collision of the hot-electrons with the walls is absorbed by the cold mass of the superconducting magnet leading to an additional heat load in the cryostat in the order of several watts. Therefore a new plasma chamber has been installed that incorporates a high-Z tantalum shield to reduce the cryostat heating and enhance water cooling to minimize the chance of burnout. In order to better understand the heat load, the spectrum of the bremsstrahlung has been carefully measured as a function of rf power, magnetic confinement, and rf frequency. In addition, the distribution of electron heating in VENUS magnetic field has been simulated with a three-dimensional computer code [H. Heinen and H. J. Andra, Proceedings of the 14th International Workshop on ECR Sources (CERN, Geneva, 1999), 224; H. J. Andra and A. Heinen, Proceedings of the 15th International Workshop on ECR lon Sources, ECRIS'02 (Jyvaeskylae, Finland 2002), 85.] to better understand the heat load distribution on the plasma chamber wall. The new plasma chamber design, results of the bremsstrahlung measurements, and the effectiveness of the high-Z shielding are described.

  11. Advanced Intermediate Heat Transport Loop Design Configurations for Hydrogen Production Using High Temperature Nuclear Reactors

    SciTech Connect

    Chang Oh; Cliff Davis; Rober Barner; Paul Pickard

    2005-11-01

    The US Department of Energy is investigating the use of high-temperature nuclear reactors to produce hydrogen using either thermochemical cycles or high-temperature electrolysis. Although the hydrogen production processes are in an early stage of development, coupling either of these processes to the high-temperature reactor requires both efficient heat transfer and adequate separation of the facilities to assure that off-normal events in the production facility do not impact the nuclear power plant. An intermediate heat transport loop will be required to separate the operations and safety functions of the nuclear and hydrogen plants. A next generation high-temperature reactor could be envisioned as a single-purpose facility that produces hydrogen or a dual-purpose facility that produces hydrogen and electricity. Early plants, such as the proposed Next Generation Nuclear Plant (NGNP), may be dual-purpose facilities that demonstrate both hydrogen and efficient electrical generation. Later plants could be single-purpose facilities. At this stage of development, both single- and dual-purpose facilities need to be understood. A number of possible configurations for a system that transfers heat between the nuclear reactor and the hydrogen and/or electrical generation plants were identified. These configurations included both direct and indirect cycles for the production of electricity. Both helium and liquid salts were considered as the working fluid in the intermediate heat transport loop. Methods were developed to perform thermal-hydraulic evaluations and cycle-efficiency evaluations of the different configurations and coolants. The thermal-hydraulic evaluations estimated the sizes of various components in the intermediate heat transport loop for the different configurations. The relative sizes of components provide a relative indication of the capital cost associated with the various configurations. Estimates of the overall cycle efficiency of the various

  12. Safety of human blood products: inactivation of retroviruses by heat treatment at 60 degrees C.

    PubMed

    Hilfenhaus, J; Mauler, R; Friis, R; Bauer, H

    1985-04-01

    Acquired immune deficiency syndrome (AIDS) can be transferred to patients by blood transfusions or human blood preparations, such as cryoprecipitates or factor VIII concentrates. Retroviruses have been discussed as infectious AIDS agents and more recently human T-lymphotropic retroviruses designated as HTLV type III and LAV (lymphadenopathy-associated virus) have been isolated from AIDS patients. Whether heat treatment at 60 degrees C (pasteurization) of liquid human plasma protein preparations inactivates retroviruses was therefore investigated. Pasteurization had already been included in the routine manufacturing process of human plasma protein preparations in order to guarantee safety with regard to hepatitis B. Since high titer preparations of human retroviruses were not available, heat inactivation was studied using Rous sarcoma virus added to the various plasma protein preparations tested. This retrovirus which was obtained in preparations of 6.0 log10 FFU/ml was shown to be at least as heat stable as two mammalian retroviruses studied, i.e., feline and simian sarcoma virus. In all of eight different plasma protein preparations tested, Rous sarcoma virus was completely inactivated after a heat treatment lasting no longer than 4 hr. It is thus concluded that pasteurization of liquid plasma protein preparations at 60 degrees C over a period of 10 hr must confer safety to these products with respect to AIDS, provided that the AIDS agents are retroviruses of comparable heat stability as Rous sarcoma virus and the mammalian retroviruses tested.

  13. Heat production rate from radioactive elements in igneous and metamorphic rocks in Eastern Desert, Egypt.

    PubMed

    Abbady, Adel G E; El-Arabi, A M; Abbady, A

    2006-01-01

    Radioactive heat-production data of Igneous and Metamorphic outcrops in the Eastern Desert are presented. Samples were analysed using a low level gamma-ray spectrometer (HPGe) in the laboratory. A total of 205 rock samples were investigated, covering all major rock types of the area. The heat-production rate of igneous rocks ranges from 0.11 (basalt) to 9.53 microWm(-3) (granite). In metamorphic rocks it varies from 0.28 (serpentinite ) to 0.91 microWm(-3) (metagabbro). The contribution due to U is about 51%, as that from Th is 31% and 18% from K. The corresponding values in igneous rocks are 76%, 19% and 5%, respectively. The calculated values showed good agreement with global values except in some areas containing granites. PMID:16120480

  14. Heat production rate from radioactive elements in igneous and metamorphic rocks in Eastern Desert, Egypt.

    PubMed

    Abbady, Adel G E; El-Arabi, A M; Abbady, A

    2006-01-01

    Radioactive heat-production data of Igneous and Metamorphic outcrops in the Eastern Desert are presented. Samples were analysed using a low level gamma-ray spectrometer (HPGe) in the laboratory. A total of 205 rock samples were investigated, covering all major rock types of the area. The heat-production rate of igneous rocks ranges from 0.11 (basalt) to 9.53 microWm(-3) (granite). In metamorphic rocks it varies from 0.28 (serpentinite ) to 0.91 microWm(-3) (metagabbro). The contribution due to U is about 51%, as that from Th is 31% and 18% from K. The corresponding values in igneous rocks are 76%, 19% and 5%, respectively. The calculated values showed good agreement with global values except in some areas containing granites.

  15. Supramaximal heat production induced by aminophylline in temperature-acclimated rats

    NASA Astrophysics Data System (ADS)

    Wang, L. C. H.

    1985-03-01

    Previous studies have shown that aminophylline, a phosphodiesterase inhibitor (thereby increasing intracellular cyclic AMP concentration) elicits supramaximal heat production and improves cold tolerance in rats acclimated to 22°C. To test whether aminophylline-stimulated supramaximal thermogenesis is independent of both the thermogenic capacity (i.e. aerobic fitness) and the mode of thermogenesis (shivering vs. non-shivering), rats (adult male Sprague-Dawley, approximately 400 g) of two different ages (4 11 month and 9 17 month, n=12 for each) were acclimated to 5, 15, and 25°C in succession and their thermogenic responses to aminophylline subsequently assessed. Aminophylline elicited supramaximal thermogenesis and improved cold tolerance regardless of age or acclimating temperatures. Further, the absolute net increase in heat production stimulated by aminophylline was also similar for all acclimating temperatures. After acclimating to 15°C, a single injection of aminophylline in the older rats elicited thermogenesis greater than that of the controls acclimated to 5°C; in the younger rats, aminophylline duplicated 46% of the increase in thermogenesis observed after acclimating to 5°C. These results indicated that the aminophylline-stimulated extra heat production is independent of both the thermogenic capacity and the mode of thermogenesis. It is possible that an enhanced substrate mobilization consequent to increased intracellular cyclic AMP concentration by aminophylline underlies the common mechanism via which supramaximal thermogenesis is elicited in temperature-acclimated rats.

  16. Technological Alternatives or Use of Wood Fuel in Combined Heat and Power Production

    NASA Astrophysics Data System (ADS)

    Rusanova, Jekaterina; Markova, Darja; Bazbauers, Gatis; Valters, Kārlis

    2013-12-01

    Abstract Latvia aims for 40% share of renewable energy in the total final energy use. Latvia has large resources of biomass and developed district heating systems. Therefore, use of biomass for heat and power production is an economically attractive path for increase of the share of renewable energy. The optimum technological solution for use of biomass and required fuel resources have to be identified for energy planning and policy purposes. The aim of this study was to compare several wood fuel based energy conversion technologies from the technical and economical point of view. Three biomass conversion technologies for combined heat and electricity production (CHP) were analyzed: • CHP with steam turbine technology; • gasification CHP using gas engine; • bio-methane combined cycle CHP. Electricity prices for each alternative are presented. The results show the level of support needed for the analyzed renewable energy technologies and time period needed to reach price parity with the natural gas - fired combined cycle gas turbine (CCGT) CHPss. The results also show that bio-methane technology is most competitive when compared with CCGT among the considered technologies regarding fuel consumption and electricity production, but it is necessary to reduce investment costs to reach the electricity price parity with the natural gas CCGT.

  17. Production of pyrolytic liquids from industrial sewage sludges in an induction-heating reactor.

    PubMed

    Tsai, Wen-Tien; Chang, Jeng-Hung; Hsien, Kuo-Jung; Chang, Yuan-Ming

    2009-01-01

    With the application of induction-heating, the pyrolytic experiments have been carried out for three sewage sludges from the food processing factories in an externally heated fixed-bed reactor. The thermochemical characteristics of sludge samples were first analyzed. The results indicated that the calorific value had about 15 MJ/kg on an average, suggesting that it had a potential for biomass energy source. However, its nitrogen concentration was relatively high. From the thermogravimetric analysis (TGA) curves, it showed that the pyrolysis reaction can be almost finished in the temperature range of 450-750 degrees C. The yields of resulting liquid and char products from the pyrolysis of sewage sludge were discussed for examining the effects of pyrolysis temperature (500-800 degrees C), heating rate (200-500 degrees C/min), and holding time (1-8 min). Overall, the variation of yield was not so significant in the experimental conditions for three sewage sludges. All results of the resulting liquid products analyzed by elemental analyzer, pH meter, Karl-Fischer moisture titrator and bomb calorimeter were in consistence with those analyses by FTIR spectroscopy. Furthermore, the pyrolysis liquid products contained large amounts of water (>73% by weight) mostly derived from the bound water in the biosludge feedstocks and the condensation reactions during the pyrolysis reaction, and fewer contents of oxygenated hydrocarbons composing of carbonyl and nitrogen-containing groups, resulting in low pH and low calorific values. PMID:18656347

  18. Ethnic differences in thermoregulatory responses during resting, passive and active heating: application of Werner's adaptation model.

    PubMed

    Lee, Joo-Young; Wakabayashi, Hitoshi; Wijayanto, Titis; Hashiguchi, Nobuko; Saat, Mohamed; Tochihara, Yutaka

    2011-12-01

    For the coherent understanding of heat acclimatization in tropical natives, we compared ethnic differences between tropical and temperate natives during resting, passive and active heating conditions. Experimental protocols included: (1) a resting condition (an air temperature of 28°C with 50% RH), (2) a passive heating condition (28°C with 50% RH; leg immersion in a hot tub at a water temperature of 42°C), and (3) an active heating condition (32°C with 70% RH; a bicycle exercise). Morphologically and physically matched tropical natives (ten Malaysian males, MY) and temperate natives (ten Japanese males, JP) participated in all three trials. The results saw that: tropical natives had a higher resting rectal temperature and lower hand and foot temperatures at rest, smaller rise of rectal temperature and greater temperature rise in bodily extremities, and a lower sensation of thirst during passive and active heating than the matched temperate natives. It is suggested that tropical natives' homeostasis during heating is effectively controlled with the improved stability in internal body temperature and the increased capability of vascular circulation in extremities, with a lower thirst sensation. The enhanced stability of internal body temperature and the extended thermoregulatory capability of vascular circulation in the extremities of tropical natives can be interpreted as an interactive change to accomplish a thermal dynamic equilibrium in hot environments. These heat adaptive traits were explained by Wilder's law of initial value and Werner's process and controller adaptation model.

  19. Studies of the use of high-temperature nuclear heat from an HTGR for hydrogen production

    NASA Technical Reports Server (NTRS)

    Peterman, D. D.; Fontaine, R. W.; Quade, R. N.; Halvers, L. J.; Jahromi, A. M.

    1975-01-01

    The results of a study which surveyed various methods of hydrogen production using nuclear and fossil energy are presented. A description of these methods is provided, and efficiencies are calculated for each case. The process designs of systems that utilize the heat from a general atomic high temperature gas cooled reactor with a steam methane reformer and feed the reformer with substitute natural gas manufactured from coal, using reforming temperatures, are presented. The capital costs for these systems and the resultant hydrogen production price for these cases are discussed along with a research and development program.

  20. An artificial HSE promoter for efficient and selective detection of heat shock pathway activity.

    PubMed

    Ortner, Viktoria; Ludwig, Alfred; Riegel, Elisabeth; Dunzinger, Sarah; Czerny, Thomas

    2015-03-01

    Detection of cellular stress is of major importance for the survival of cells. During evolution, a network of stress pathways developed, with the heat shock (HS) response playing a major role. The key transcription factor mediating HS signalling activity in mammalian cells is the HS factor HSF1. When activated it binds to the heat shock elements (HSE) in the promoters of target genes like heat shock protein (HSP) genes. They are induced by HSF1 but in addition they integrate multiple signals from different stress pathways. Here, we developed an artificial promoter consisting only of HSEs and therefore selectively reacting to HSF-mediated pathway activation. The promoter is highly inducible but has an extreme low basal level. Direct comparison with the HSPA1A promoter activity indicates that heat-dependent expression can be fully recapitulated by isolated HSEs in human cells. Using this sensitive reporter, we measured the HS response for different temperatures and exposure times. In particular, long heat induction times of 1 or 2 h were compared with short heat durations down to 1 min, conditions typical for burn injuries. We found similar responses to both long and short heat durations but at completely different temperatures. Exposure times of 2 h result in pathway activation at 41 to 44 °C, whereas heat pulses of 1 min lead to a maximum HS response between 47 and 50 °C. The results suggest that the HS response is initiated by a combination of temperature and exposure time but not by a certain threshold temperature.

  1. Arabidopsis HEAT SHOCK TRANSCRIPTION FACTORA1b overexpression enhances water productivity, resistance to drought, and infection.

    PubMed

    Bechtold, Ulrike; Albihlal, Waleed S; Lawson, Tracy; Fryer, Michael J; Sparrow, Penelope A C; Richard, François; Persad, Ramona; Bowden, Laura; Hickman, Richard; Martin, Cathie; Beynon, Jim L; Buchanan-Wollaston, Vicky; Baker, Neil R; Morison, James I L; Schöffl, Friedrich; Ott, Sascha; Mullineaux, Philip M

    2013-08-01

    Heat-stressed crops suffer dehydration, depressed growth, and a consequent decline in water productivity, which is the yield of harvestable product as a function of lifetime water consumption and is a trait associated with plant growth and development. Heat shock transcription factor (HSF) genes have been implicated not only in thermotolerance but also in plant growth and development, and therefore could influence water productivity. Here it is demonstrated that Arabidopsis thaliana plants with increased HSFA1b expression showed increased water productivity and harvest index under water-replete and water-limiting conditions. In non-stressed HSFA1b-overexpressing (HSFA1bOx) plants, 509 genes showed altered expression, and these genes were not over-represented for development-associated genes but were for response to biotic stress. This confirmed an additional role for HSFA1b in maintaining basal disease resistance, which was stress hormone independent but involved H₂O₂ signalling. Fifty-five of the 509 genes harbour a variant of the heat shock element (HSE) in their promoters, here named HSE1b. Chromatin immunoprecipitation-PCR confirmed binding of HSFA1b to HSE1b in vivo, including in seven transcription factor genes. One of these is MULTIPROTEIN BRIDGING FACTOR1c (MBF1c). Plants overexpressing MBF1c showed enhanced basal resistance but not water productivity, thus partially phenocopying HSFA1bOx plants. A comparison of genes responsive to HSFA1b and MBF1c overexpression revealed a common group, none of which harbours a HSE1b motif. From this example, it is suggested that HSFA1b directly regulates 55 HSE1b-containing genes, which control the remaining 454 genes, collectively accounting for the stress defence and developmental phenotypes of HSFA1bOx.

  2. Arabidopsis HEAT SHOCK TRANSCRIPTION FACTORA1b overexpression enhances water productivity, resistance to drought, and infection.

    PubMed

    Bechtold, Ulrike; Albihlal, Waleed S; Lawson, Tracy; Fryer, Michael J; Sparrow, Penelope A C; Richard, François; Persad, Ramona; Bowden, Laura; Hickman, Richard; Martin, Cathie; Beynon, Jim L; Buchanan-Wollaston, Vicky; Baker, Neil R; Morison, James I L; Schöffl, Friedrich; Ott, Sascha; Mullineaux, Philip M

    2013-08-01

    Heat-stressed crops suffer dehydration, depressed growth, and a consequent decline in water productivity, which is the yield of harvestable product as a function of lifetime water consumption and is a trait associated with plant growth and development. Heat shock transcription factor (HSF) genes have been implicated not only in thermotolerance but also in plant growth and development, and therefore could influence water productivity. Here it is demonstrated that Arabidopsis thaliana plants with increased HSFA1b expression showed increased water productivity and harvest index under water-replete and water-limiting conditions. In non-stressed HSFA1b-overexpressing (HSFA1bOx) plants, 509 genes showed altered expression, and these genes were not over-represented for development-associated genes but were for response to biotic stress. This confirmed an additional role for HSFA1b in maintaining basal disease resistance, which was stress hormone independent but involved H₂O₂ signalling. Fifty-five of the 509 genes harbour a variant of the heat shock element (HSE) in their promoters, here named HSE1b. Chromatin immunoprecipitation-PCR confirmed binding of HSFA1b to HSE1b in vivo, including in seven transcription factor genes. One of these is MULTIPROTEIN BRIDGING FACTOR1c (MBF1c). Plants overexpressing MBF1c showed enhanced basal resistance but not water productivity, thus partially phenocopying HSFA1bOx plants. A comparison of genes responsive to HSFA1b and MBF1c overexpression revealed a common group, none of which harbours a HSE1b motif. From this example, it is suggested that HSFA1b directly regulates 55 HSE1b-containing genes, which control the remaining 454 genes, collectively accounting for the stress defence and developmental phenotypes of HSFA1bOx. PMID:23828547

  3. Production of tritium, neutrons, and heat based on the transmission resonance model (TRM) for cold fusion

    NASA Astrophysics Data System (ADS)

    Bush, Robert T.

    1991-05-01

    The TRM has recently been successful in fitting calorimetric data having interesting nonlinear structure. The model appears to provide a natural description for electrolytic cold fusion in terms of ``fractals''. Extended to the time dimension, the model can apparently account for the phenomenon of heat ``bursts''. The TRM combines a transmission condition involving quantized energies and an engergy shift of a Maxwell-Boltzmann energy distribution of deuterons at the cathodic surface that appears related to the concentration overpotential (hydrogen overvoltage). The model suggest three possible regimes vis-a-vis tritium production in terms of this energy shift, and indicates why measurable tritium production in the electrolytic case will tend to be the exception rather than the rule in absence of a recipe: Below a shift of approximately 2.8 meV there is production of both tritium and measureable excess heat, with the possibility of accounting for the Bockris curve indicating about a 1% correlation between excess heat and tritium. However, over the large range from about 2.8 meV to 340 meV energy shift there is a regime of observable excess heat production but little, and probably no measurable, tritium production. The third regime is more hypothetical: It begins at an energy shift of about 1 keV and extends to the boundaries of ``hot'' fusion at about 10 keV. A new type of nucelar reaction, trint (for transmission resonance-induced neutron transfer), is suggested by the model leading to triton and neutron production. A charge distribution ``polarization conjecture'' is the basis for theoretical derivation for the low-energy limit for an energy-dependent branching ratio for D-on-D. When the values of the parameters are inserted, this expression yields an estimate for the ratio of neutron-to-triton production of about 1.64×10-9. The possibility of some three-body reactions is also suggested. A comparison of the TRM's transmission energy levels for palladium deuteride

  4. 3D slicing of radiogenic heat production in Bahariya Formation, Tut oil field, North-Western Desert, Egypt.

    PubMed

    Al-Alfy, I M; Nabih, M A

    2013-03-01

    A 3D block of radiogenic heat production was constructed from the subsurface total gamma ray logs of Bahariya Formation, Western Desert, Egypt. The studied rocks possess a range of radiogenic heat production varying from 0.21 μWm(-3) to 2.2 μWm(-3). Sandstone rocks of Bahariya Formation have higher radiogenic heat production than the average for crustal sedimentary rocks. The high values of density log of Bahariya Formation indicate the presence of iron oxides which contribute the uranium radioactive ores that increase the radiogenic heat production of these rocks. The average radiogenic heat production produced from the study area is calculated as 6.3 kW. The histogram and cumulative frequency analyses illustrate that the range from 0.8 to 1.2 μWm(-3) is about 45.3% of radiogenic heat production values. The 3D slicing of the reservoir shows that the southeastern and northeastern parts of the study area have higher radiogenic heat production than other parts. PMID:23291561

  5. 3D slicing of radiogenic heat production in Bahariya Formation, Tut oil field, North-Western Desert, Egypt.

    PubMed

    Al-Alfy, I M; Nabih, M A

    2013-03-01

    A 3D block of radiogenic heat production was constructed from the subsurface total gamma ray logs of Bahariya Formation, Western Desert, Egypt. The studied rocks possess a range of radiogenic heat production varying from 0.21 μWm(-3) to 2.2 μWm(-3). Sandstone rocks of Bahariya Formation have higher radiogenic heat production than the average for crustal sedimentary rocks. The high values of density log of Bahariya Formation indicate the presence of iron oxides which contribute the uranium radioactive ores that increase the radiogenic heat production of these rocks. The average radiogenic heat production produced from the study area is calculated as 6.3 kW. The histogram and cumulative frequency analyses illustrate that the range from 0.8 to 1.2 μWm(-3) is about 45.3% of radiogenic heat production values. The 3D slicing of the reservoir shows that the southeastern and northeastern parts of the study area have higher radiogenic heat production than other parts.

  6. A novel heat flux study of a geothermally active lake - Lake Rotomahana, New Zealand

    NASA Astrophysics Data System (ADS)

    Tivey, Maurice A.; de Ronde, Cornel E. J.; Tontini, Fabio Caratori; Walker, Sharon L.; Fornari, Daniel J.

    2016-03-01

    A new technique for measuring conductive heat flux in a lake was adapted from the marine environment to allow for multiple measurements to be made in areas where bottom sediment cover is sparse, or even absent. This thermal blanket technique, pioneered in the deep ocean for use in volcanic mid-ocean rift environments, was recently used in the geothermally active Lake Rotomahana, New Zealand. Heat flow from the lake floor propagates into the 0.5 m diameter blanket and establishes a thermal gradient across the known blanket thickness and thereby provides an estimate of the conductive heat flux of the underlying terrain. This approach allows conductive heat flux to be measured over a spatially dense set of stations in a relatively short period of time. We used 10 blankets and deployed them for 1 day each to complete 110 stations over an 11-day program in the 6 × 3 km lake. Results show that Lake Rotomahana has a total conductive heat flux of about 47 MW averaging 6 W/m2 over the geothermally active lake. The western half of the lake has two main areas of high heat flux; 1) a high heat flux area averaging 21.3 W/m2 along the western shoreline, which is likely the location of the pre-existing geothermal system that fed the famous Pink Terraces, mostly destroyed during the 1886 eruption 2) a region southwest of Patiti Island with a heat flux averaging 13.1 W/m2 that appears to be related to the explosive rift that formed the lake in the 1886 Tarawera eruption. A small rise in bottom water temperature over the survey period of 0.01 °C/day suggests the total thermal output of the lake is ~ 112-132 MW and when compared to the conductive heat output suggests that 18-42% of the total thermal energy is by conductive heat transfer.

  7. The effect of pH on the heat production and membrane resistance of Streptococcus bovis.

    PubMed

    Russell, J B

    1992-01-01

    Non-growing cultures of Streptococcus bovis JB1 which were incubated in 2-[N-moropholino] ethane-sulfonic acid (MES)-phosphate buffer (pH 6.8) and glucose (2 g/l) produced heat at a rate of 0.17 mW/mg protein, and this rate was proportional to the enthalpy change of the homolactic fermentation. Since the growth-independent heat production could be eliminated by dicyclohexylcarbodiimide (DCCD), an inhibitor of F1F0 ATPases, it appeared that virtually all of the energy was being used to counteract proton flux through the cell membrane. When the pH was decreased from 6.8 to 5.8, heat production and glucose consumption increased, the electrical potential (delta psi) declined, the chemical gradient of protons (Z delta pH) increased, and there was a small increase in total protonmotive force (delta p). Further decreases in pH (5.8 to 4.5) caused a marked decrease in heat production and glucose consumption even though there was only a small decline in membrane voltage. Based on the enthalpy of ATP (4 kcal or 16.8 kJ/mol), it appeared that 38% of the wattage was passing through the cell membrane. The relationship between membrane voltage and membrane wattage or glucose consumption was non-linear (non-ohmic), and it appeared that the resistance of the membrane to current flow was not constant. Based on the electrical formula, resistance = voltage2/wattage and resistance = voltage/amperage, there was a marked increase in membrane resistance when the pH was less than 6.0. The increase in membrane resistance at low pH allowed S. bovis to maintain its membrane potential and expend less energy when its ability to ferment glucose was impaired. PMID:1444715

  8. Cardiopulmonary baroreceptor control of muscle sympathetic nerve activity in heat-stressed humans

    NASA Technical Reports Server (NTRS)

    Crandall, C. G.; Etzel, R. A.; Farr, D. B.

    1999-01-01

    Whole body heating decreases central venous pressure (CVP) while increasing muscle sympathetic nerve activity (MSNA). In normothermia, similar decreases in CVP elevate MSNA, presumably via cardiopulmonary baroreceptor unloading. The purpose of this project was to identify whether increases in MSNA during whole body heating could be attributed to cardiopulmonary baroreceptor unloading coincident with the thermal challenge. Seven subjects were exposed to whole body heating while sublingual temperature, skin blood flow, heart rate, arterial blood pressure, and MSNA were monitored. During the heat stress, 15 ml/kg warmed saline was infused intravenously over 7-10 min to increase CVP and load the cardiopulmonary baroreceptors. We reported previously that this amount of saline was sufficient to return CVP to pre-heat stress levels. Whole body heating increased MSNA from 25 +/- 3 to 39 +/- 3 bursts/min (P < 0. 05). Central blood volume expansion via rapid saline infusion did not significantly decrease MSNA (44 +/- 4 bursts/min, P > 0.05 relative to heat stress period) and did not alter mean arterial blood pressure (MAP) or pulse pressure. To identify whether arterial baroreceptor loading decreases MSNA during heat stress, in a separate protocol MAP was elevated via steady-state infusion of phenylephrine during whole body heating. Increasing MAP from 82 +/- 3 to 93 +/- 4 mmHg (P < 0.05) caused MSNA to decrease from 36 +/- 3 to 15 +/- 4 bursts/min (P < 0.05). These data suggest that cardiopulmonary baroreceptor unloading during passive heating is not the primary mechanism resulting in elevations in MSNA. Moreover, arterial baroreceptors remain capable of modulating MSNA during heat stress.

  9. Chemical States of Bacterial Spores: Heat Resistance and Its Kinetics at Intermediate Water Activity

    PubMed Central

    Alderton, Gordon; Snell, Neva

    1970-01-01

    Bacterial spore heat resistance at intermediate water activity, like aqueous and strictly dry heat resistance, is a property manipulatable by chemical pretreatments of the dormant mature spore. Heat resistances differ widely, and survival is prominently nonlogarithmic for both chemical forms of the spore. Log survival varies approximately as the cube of time for the resistant state of Bacillus stearothermophilus spores and as the square of time for the sensitive state. A method for measuring heat resistance at intermediate humidity was designed to provide direct and unequivocal control of water vapor concentration with quick equilibration, maintenance of known spore state, and dispersion of spores singly for valid survivor counting. Temperature characteristics such as z, Ea, and Q10 cannot be determined in the usual sense (as a spore property) for spores encapsulated with a constant weight of water. Effect on spore survival of temperature induced changes of water activity in such systems is discussed. PMID:5418938

  10. Influence of heat treatment of rayon-based activated carbon fibers on the adsorption of formaldehyde.

    PubMed

    Rong, Haiqin; Ryu, Zhenyu; Zheng, Jingtang; Zhang, Yuanli

    2003-05-15

    The influence of heat treatment of rayon-based activated carbon fibers on the adsorption behavior of formaldehyde was studied. Heat treatment in an inert atmosphere of nitrogen for rayon-based activated carbon fibers (ACFs) resulted in a significant increase in the adsorption capacities and prolongation of breakthrough time on removing of formaldehyde. The effect of different heat-treatment conditions on the adsorption characteristics was investigated. The porous structure parameters of the samples under study were investigated using nitrogen adsorption at the low temperature 77.4 K. The pore size distributions of the samples under study were calculated by density functional theory. With the aid of these analyses, the relationship between structure and adsorption properties of rayon-based ACFs for removing formaldehyde was revealed. Improvement of their performance in terms of adsorption selectivity and adsorption rate for formaldehyde were achieved by heat post-treatment in an inert atmosphere of nitrogen.

  11. Heat removal from high temperature tubular solid oxide fuel cells utilizing product gas from coal gasifiers.

    SciTech Connect

    Parkinson, W. J. ,

    2003-01-01

    In this work we describe the results of a computer study used to investigate the practicality of several heat exchanger configurations that could be used to extract heat from tubular solid oxide fuel cells (SOFCs) . Two SOFC feed gas compositions were used in this study. They represent product gases from two different coal gasifier designs from the Zero Emission Coal study at Los Alamos National Laboratory . Both plant designs rely on the efficient use of the heat produced by the SOFCs . Both feed streams are relatively rich in hydrogen with a very small hydrocarbon content . One feed stream has a significant carbon monoxide content with a bit less hydrogen . Since neither stream has a significant hydrocarbon content, the common use of the endothermic reforming reaction to reduce the process heat is not possible for these feed streams . The process, the method, the computer code, and the results are presented as well as a discussion of the pros and cons of each configuration for each process .

  12. In vivo chaperone activity of heat shock protein 70 and thermotolerance.

    PubMed

    Nollen, E A; Brunsting, J F; Roelofsen, H; Weber, L A; Kampinga, H H

    1999-03-01

    Heat shock protein 70 (Hsp70) is thought to play a critical role in the thermotolerance of mammalian cells, presumably due to its chaperone activity. We examined the chaperone activity and cellular heat resistance of a clonal cell line in which overexpression of Hsp70 was transiently induced by means of the tetracycline-regulated gene expression system. This single-cell-line approach circumvents problems associated with clonal variation and indirect effects resulting from constitutive overexpression of Hsp70. The in vivo chaperone function of Hsp70 was quantitatively investigated by using firefly luciferase as a reporter protein. Chaperone activity was found to strictly correlate to the level of Hsp70 expression. In addition, we observed an Hsp70 concentration dependent increase in the cellular heat resistance. In order to study the contribution of the Hsp70 chaperone activity, heat resistance of cells that expressed tetracycline-regulated Hsp70 was compared to thermotolerant cells expressing the same level of Hsp70 plus all of the other heat shock proteins. Overexpression of Hsp70 alone was sufficient to induce a similar recovery of cytoplasmic luciferase activity, as does expression of all Hsps in thermotolerant cells. However, when the luciferase reporter protein was directed to the nucleus, expression of Hsp70 alone was not sufficient to yield the level of recovery observed in thermotolerant cells. In addition, cells expressing the same level of Hsp70 found in heat-induced thermotolerant cells containing additional Hsps showed increased resistance to thermal killing but were more sensitive than thermotolerant cells. These results suggest that the inducible form of Hsp70 contributes to the stress-tolerant state by increasing the chaperone activity in the cytoplasm. However, its expression alone is apparently insufficient for protection of other subcellular compartments to yield clonal heat resistance to the level observed in thermotolerant cells.

  13. [Heat transfer analysis of liquid cooling garment used for extravehicular activity].

    PubMed

    Qiu, Y F; Yuan, X G; Mei, Z G; Jia, S G; Ouyang, H; Ren, Z S

    2001-10-01

    Brief description was given about the construction and function of the LCG (liquid cooling garment) used for EVA (extravehicular activity). The heat convection was analyzed between ventilating gas and LCG, the heat and mass transfer process was analyzed too, then a heat and mass transfer mathematical model of LCG was developed. Thermal physiological experimental study with human body wearing LVCG (liquid cooling and ventilation garment) used for EVA was carried out to verify this mathematical model. This study provided a basis for the design of liquid-cooling and ventilation system for the space suit.

  14. A JOULE-HEATED MELTER TECHNOLOGY FOR THE TREATMENT AND IMMOBILIZATION OF LOW-ACTIVITY WASTE

    SciTech Connect

    KELLY SE

    2011-04-07

    This report is one of four reports written to provide background information regarding immobilization technologies remaining under consideration for supplemental immobilization of Hanford's low-activity waste. This paper provides the reader a general understanding of joule-heated ceramic lined melters and their application to Hanford's low-activity waste.

  15. Product formulation for ohmic heating: blanching as a pretreatment method to improve uniformity in heating of solid-liquid food mixtures.

    PubMed

    Sarang, S; Sastry, S K; Gaines, J; Yang, T C S; Dunne, P

    2007-06-01

    The electrical conductivity of food components is critical to ohmic heating. Food components of different electrical conductivities heat at different rates. While equal electrical conductivities of all phases are desirable, real food products may behave differently. In the present study involving chicken chow mein consisting of a sauce and different solid components, celery, water chestnuts, mushrooms, bean sprouts, and chicken, it was observed that the sauce was more conductive than all solid components over the measured temperature range. To improve heating uniformity, a blanching method was developed to increase the ionic content of the solid components. By blanching different solid components in a highly conductive sauce at 100 degrees C for different lengths of time, it was possible to adjust their conductivity to that of the sauce. Chicken chow mein samples containing blanched particulates were compared with untreated samples with respect to ohmic heating uniformity at 60 Hz up to 140 degrees C. All components of the treated product containing blanched solids heated more uniformly than untreated product. In sensory tests, 3 different formulations of the blanched product showed good quality attributes and overall acceptability, demonstrating the practical feasibility of the blanching protocol.

  16. Electric currents and coronal heating in NOAA active region 6952

    NASA Technical Reports Server (NTRS)

    Metcalf, T. R.; Canfield, R. C.; Hudson, H. S.; Mickey, D. L.; Wulser, J. -P.; Martens, P. C. H.; Tsuneta, S.

    1994-01-01

    We examine the spatial and temporal relationship between coronal structures observed with the soft X-ray telescope (SXT) on board the Yohkoh spacecraft and the vertical electric current density derived from photospheric vector magnetograms obtained using the Stokes Polarimeter at the Mees Solar Observatory. We focus on a single active region: AR 6952 which we observed on 7 days during 1991 December. For 11 independent maps of the vertical electric current density co-aligned with non-flaring X-ray images, we search for a morphological relationship between sites of high vertical current density in the photosphere and enhanced X-ray emission in the overlying corona. We find no compelling spatial or temporal correlation between the sites of vertical current and the bright X-ray structures in this active region.

  17. Effect of Ligustrum lucidum and Schisandra chinensis on the egg production, antioxidant status and immunity of laying hens during heat stress.

    PubMed

    Ma, Deying; Shan, Anshan; Chen, Zhihui; Du, Juan; Song, Kai; Li, Jianping; Xu, Qiyou

    2005-12-01

    The experiment was conducted to evaluate the effect of two plants belonging to Chinese herbal medicines, Ligustrum lucidum (LL) and Schisandra chinensis (SC), on the laying performance, antioxidant status and immunity of hens during heat stress. The results showed that diets supplement with 1% of either LL or SC had beneficial effects on egg production and FCR of hens during heat stress (p < 0.05), compared with the control group. Either LL or SC significantly reduced malondialdehyde (MDA) concentration of heart, liver, sera and egg yolk. In addition, glutathione reductase (GR) activity of tissues and sera of the birds was significantly elevated by supplementation LL or SC. Furthermore, LL or SC supplementation significantly elevated lymphoblastogenese of the birds and the antibody values against Newcastle disease virus (NDV). The results suggest that diets supplement with 1% of either LL or SC may enhance egg production, immune function, and antioxidant status of hens during heat stress. PMID:16429829

  18. Genetic variations alter production and behavioral responses following heat stress in 2 strains of laying hens.

    PubMed

    Mack, L A; Felver-Gant, J N; Dennis, R L; Cheng, H W

    2013-02-01

    Genetic differences alter the type and degree of hens' responses and their ability to adapt to a stressor. This study examined the effects of genotypic variations on the productivity and behavior of laying hens following heat stress (HS). Two strains of White Leghorn hens were used: DXL (Dekalb XL), a commercial strain individually selected for egg production and KGB (kind, gentle bird), a strain selected for high group productivity and survivability. Ninety hens (48 DXL and 42 KGB) at 28 wk of age were randomly assigned to either a hot (H: mean = 32.6°C) or control (C: mean = 24.3°C) treatment and housed in pairs by strain for 9 d. Egg production and quality, behavior, body and organ weights, and circulating hormone concentrations were measured. Heat-stressed hens had lower egg production [adjusted (adj) P < 0.001] than their respective controls. Among H-DXL hens, egg weight tended to be reduced at d 1 and was reduced at d 9 (adj P = 0.007), but was reduced only at d 9 among H-KGB hens (adj P = 0.007). Eggshell thickness was also reduced among H hens at d 9 (adj P = 0.007), especially among H-KGB hens (adj P = 0.01). Plasma triiodothyronine concentration was reduced among H-hens (adj P = 0.01), especially among H-DXL hens (adj P = 0.01). Neither temperature nor strain affected the plasma thyroxine and plasma and yolk corticosterone concentrations. Heat-stressed hens spent less time walking (adj P = 0.001) and more time drinking (adj P = 0.007) and resting (adj P = 0.001) than C-hens. The results indicate that although HS reduced production and caused behavioral changes among hens from both strains, the responses differed by genotype. The data provide evidence that genetic selection is a useful strategy for reducing HS response in laying hens. The results provide insights for conducting future studies to develop heat-resistant strains to improve hen well-being, especially under the current commercial conditions.

  19. A pain-inducing centipede toxin targets the heat activation machinery of nociceptor TRPV1

    NASA Astrophysics Data System (ADS)

    Yang, Shilong; Yang, Fan; Wei, Ningning; Hong, Jing; Li, Bowen; Luo, Lei; Rong, Mingqiang; Yarov-Yarovoy, Vladimir; Zheng, Jie; Wang, Kewei; Lai, Ren

    2015-09-01

    The capsaicin receptor TRPV1 ion channel is a polymodal nociceptor that responds to heat with exquisite sensitivity through an unknown mechanism. Here we report the identification of a novel toxin, RhTx, from the venom of the Chinese red-headed centipede that potently activates TRPV1 to produce excruciating pain. RhTx is a 27-amino-acid small peptide that forms a compact polarized molecule with very rapid binding kinetics and high affinity for TRPV1. We show that RhTx targets the channel's heat activation machinery to cause powerful heat activation at body temperature. The RhTx-TRPV1 interaction is mediated by the toxin's highly charged C terminus, which associates tightly to the charge-rich outer pore region of the channel where it can directly interact with the pore helix and turret. These findings demonstrate that RhTx binding to the outer pore can induce TRPV1 heat activation, therefore providing crucial new structural information on the heat activation machinery.

  20. A pain-inducing centipede toxin targets the heat activation machinery of nociceptor TRPV1.

    PubMed

    Yang, Shilong; Yang, Fan; Wei, Ningning; Hong, Jing; Li, Bowen; Luo, Lei; Rong, Mingqiang; Yarov-Yarovoy, Vladimir; Zheng, Jie; Wang, KeWei; Lai, Ren

    2015-09-30

    The capsaicin receptor TRPV1 ion channel is a polymodal nociceptor that responds to heat with exquisite sensitivity through an unknown mechanism. Here we report the identification of a novel toxin, RhTx, from the venom of the Chinese red-headed centipede that potently activates TRPV1 to produce excruciating pain. RhTx is a 27-amino-acid small peptide that forms a compact polarized molecule with very rapid binding kinetics and high affinity for TRPV1. We show that RhTx targets the channel's heat activation machinery to cause powerful heat activation at body temperature. The RhTx-TRPV1 interaction is mediated by the toxin's highly charged C terminus, which associates tightly to the charge-rich outer pore region of the channel where it can directly interact with the pore helix and turret. These findings demonstrate that RhTx binding to the outer pore can induce TRPV1 heat activation, therefore providing crucial new structural information on the heat activation machinery.

  1. A pain-inducing centipede toxin targets the heat activation machinery of nociceptor TRPV1.

    PubMed

    Yang, Shilong; Yang, Fan; Wei, Ningning; Hong, Jing; Li, Bowen; Luo, Lei; Rong, Mingqiang; Yarov-Yarovoy, Vladimir; Zheng, Jie; Wang, KeWei; Lai, Ren

    2015-01-01

    The capsaicin receptor TRPV1 ion channel is a polymodal nociceptor that responds to heat with exquisite sensitivity through an unknown mechanism. Here we report the identification of a novel toxin, RhTx, from the venom of the Chinese red-headed centipede that potently activates TRPV1 to produce excruciating pain. RhTx is a 27-amino-acid small peptide that forms a compact polarized molecule with very rapid binding kinetics and high affinity for TRPV1. We show that RhTx targets the channel's heat activation machinery to cause powerful heat activation at body temperature. The RhTx-TRPV1 interaction is mediated by the toxin's highly charged C terminus, which associates tightly to the charge-rich outer pore region of the channel where it can directly interact with the pore helix and turret. These findings demonstrate that RhTx binding to the outer pore can induce TRPV1 heat activation, therefore providing crucial new structural information on the heat activation machinery. PMID:26420335

  2. A pain-inducing centipede toxin targets the heat activation machinery of nociceptor TRPV1

    PubMed Central

    Yang, Shilong; Yang, Fan; Wei, Ningning; Hong, Jing; Li, Bowen; Luo, Lei; Rong, Mingqiang; Yarov-Yarovoy, Vladimir; Zheng, Jie; Wang, KeWei; Lai, Ren

    2015-01-01

    The capsaicin receptor TRPV1 ion channel is a polymodal nociceptor that responds to heat with exquisite sensitivity through an unknown mechanism. Here we report the identification of a novel toxin, RhTx, from the venom of the Chinese red-headed centipede that potently activates TRPV1 to produce excruciating pain. RhTx is a 27-amino-acid small peptide that forms a compact polarized molecule with very rapid binding kinetics and high affinity for TRPV1. We show that RhTx targets the channel's heat activation machinery to cause powerful heat activation at body temperature. The RhTx–TRPV1 interaction is mediated by the toxin's highly charged C terminus, which associates tightly to the charge-rich outer pore region of the channel where it can directly interact with the pore helix and turret. These findings demonstrate that RhTx binding to the outer pore can induce TRPV1 heat activation, therefore providing crucial new structural information on the heat activation machinery. PMID:26420335

  3. AVERAGE HEATING RATE OF HOT ATMOSPHERES IN DISTANT CLUSTERS BY RADIO ACTIVE GALACTIC NUCLEUS: EVIDENCE FOR CONTINUOUS ACTIVE GALACTIC NUCLEUS HEATING

    SciTech Connect

    Ma, C.-J.; McNamara, B. R.; Schaffer, R.; Nulsen, P. E. J.; Vikhlinin, A.

    2011-10-20

    We examine atmospheric heating by radio active galactic nuclei (AGNs) in distant X-ray clusters by cross correlating clusters selected from the 400 Square Degree (400SD) X-ray Cluster survey with radio sources in the NRAO VLA Sky Survey. Roughly 30% of the clusters show radio emission above a flux threshold of 3 mJy within a projected radius of 250 kpc. The radio emission is presumably associated with the brightest cluster galaxy. The mechanical jet power for each radio source was determined using scaling relations between radio power and cavity (mechanical) power determined for nearby clusters, groups, and galaxies with hot atmospheres containing X-ray cavities. The average jet power of central radio AGNs is approximately 2 x 10{sup 44} erg s{sup -1}. We find no significant correlation between radio power, and hence mechanical jet power, and the X-ray luminosities of clusters in the redshift range 0.1-0.6. This implies that the mechanical heating rate per particle is higher in lower mass, lower X-ray luminosity clusters. The jet power averaged over the sample corresponds to an atmospheric heating of approximately 0.2 keV per particle within R{sub 500}. Assuming the current AGN heating rate does not evolve but remains constant to redshifts of 2, the heating rate per particle would rise by a factor of two. We find that the energy injected from radio AGNs contribute substantially to the excess entropy in hot atmospheres needed to break self-similarity in cluster scaling relations. The detection frequency of radio AGNs is inconsistent with the presence of strong cooling flows in 400SD clusters, but does not exclude weak cooling flows. It is unclear whether central AGNs in 400SD clusters are maintained by feedback at the base of a cooling flow. Atmospheric heating by radio AGNs may retard the development of strong cooling flows at early epochs.

  4. Heat shock protein 70 down-regulates the production of toll-like receptor-induced pro-inflammatory cytokines by a heat shock factor-1/constitutive heat shock element-binding factor-dependent mechanism

    PubMed Central

    2014-01-01

    Background Heat shock protein 70 (Hsp70) is an intracellular chaperone protein with regulatory and cytoprotective functions. Hsp70 can also be found in the extracellular milieu, as a result of active secretion or passive release from damaged cells. The role of extracellular Hsp70 is not fully understood. Some studies report that it activates monocytes, macrophages and dendritic cells through innate immune receptors (such as Toll-like receptors, TLRs), while others report that Hsp70 is a negative regulator of the inflammatory response. In order to address this apparent inconsistency, in this study we evaluated the response of human monocytes to a highly purified recombinant Hsp70. Methods Human peripheral blood monocytes were stimulated with Hsp70, alone or in combination with TLR agonists. Cytokines were quantified in culture supernatants, their mRNAs were measured by RT-PCR, and the binding of transcription factors was evaluated by electrophoretic mobility shift assay (EMSA). Kruskal-Wallis test or one-way or two-way ANOVA were used to analyze the data. Results The addition of Hsp70 to TLR-activated monocytes down-regulated TNF-α as well as IL-6 levels. This effect was independent of a physical interaction between Hsp70 and TLR agonists; instead it resulted of changes at the TNF-α gene expression level. The decrease in TNF-α expression correlated with the binding of HSF-1 (heat shock transcription factor 1, a transcription factor activated in response to Hsp70) and CHBF (constitutive HSE-binding factor) to the TNF-α gene promoter. Conclusion Extracellular Hsp70 negatively regulates the production of pro-inflammatory cytokines of monocytes exposed to TLR agonists and contributes to dampen the inflammatory response. PMID:25053922

  5. Comment on 'A reinterpretation of the linear heat flow and heat production relationship for the exponential model of the heat production in the crust' by R.N. Singh & J.G. Negi.

    USGS Publications Warehouse

    Lachenbruch, A.H.

    1980-01-01

    In their recent paper, Singh & Negi, (This journal, 57, 741-744) contend that if thd slope of the empirical linear relation between heat flow and heat production is interpreted as the decay-length of an exponential depth-distribution of sources, a discrepancy rises, whereas if it is interpreted as the depth of a step distribution, it does not. I should like to point out that their discrepancy follows from their arbitrary assumption of one of a range of physical possibilities unconstrained by the observations; with an equally valid alternate assumption (Lachenbruch 1970) the discrepancy disappears. In any case such discrepancies are probably minor compared to physical difficulties that arise from the step model, and to uncertainties introduced by other assumptions in any simple model.-Author

  6. Induction of the heat shock regulon of Escherichia coli markedly increases production of bacterial viruses at high temperatures.

    PubMed Central

    Wiberg, J S; Mowrey-McKee, M F; Stevens, E J

    1988-01-01

    Production of bacteriophages T2, T4, and T6 at 42.8 to 44 degrees C was increased from 8- to 260-fold by adapting the Escherichia coli host (grown at 30 degrees C) to growth at the high temperature for 8 min before infection; this increase was abolished if the host htpR (rpoH) gene was inactive. Others have shown that the htpR protein increases or activates the synthesis of at least 17 E. coli heat shock proteins upon raising the growth temperature above a certain level. At 43.8 to 44 degrees C in T4-infected, unadapted cells, the rates of RNA, DNA, and protein synthesis were about 100, 70, and 70%, respectively, of those in T4-infected, adapted cells. Production of the major processed capsid protein, gp23, was reduced significantly more than that of most other T4 proteins in unadapted cells relative to adapted cells. Only 4.6% of the T4 DNA made in unadapted cells was resistant to micrococcal nuclease, versus 50% in adapted cells. Thus, defective maturation of T4 heads appears to explain the failure of phage production in unadapted cells. Overproduction of the heat shock protein GroEL from plasmids restored T4 production in unadapted cells to about 50% of that seen in adapted cells. T4-infected, adapted E. coli B at around 44 degrees C exhibited a partial tryptophan deficiency; this correlated with reduced uptake of uracil that is probably caused by partial induction of stringency. Production of bacteriophage T7 at 44 degrees C was increased two- to fourfold by adapting the host to 44 degrees C before infection; evidence against involvement of the htpR (rpoH) gene is presented. This work and recent work with bacteriophage lambda (C. Waghorne and C.R. Fuerst, Virology 141:51-64, 1985) appear to represent the first demonstrations for any virus that expression of the heat shock regulon of a host is necessary for virus production at high temperature. Images PMID:2446014

  7. Demand for waste as fuel in the swedish district heating sector: a production function approach.

    PubMed

    Furtenback, Orjan

    2009-01-01

    This paper evaluates inter-fuel substitution in the Swedish district heating industry by analyzing almost all the district heating plants in Sweden in the period 1989-2003, specifically those plants incinerating waste. A multi-output plant-specific production function is estimated using panel data methods. A procedure for weighting the elasticities of factor demand to produce a single matrix for the whole industry is introduced. The price of waste is assumed to increase in response to the energy and CO2 tax on waste-to-energy incineration that was introduced in Sweden on 1 July 2006. Analysis of the plants involved in waste incineration indicates that an increase in the net price of waste by 10% is likely to reduce the demand for waste by 4.2%, and increase the demand for bio-fuels, fossil fuels, other fuels and electricity by 5.5%, 6.0%, 6.0% and 6.0%, respectively.

  8. Effect of catalytic pyrolysis conditions using pulse current heating method on pyrolysis products of wood biomass.

    PubMed

    Honma, Sensho; Hata, Toshimitsu; Watanabe, Takashi

    2014-01-01

    The influence of catalysts on the compositions of char and pyrolysis oil obtained by pyrolysis of wood biomass with pulse current heating was studied. The effects of catalysts on product compositions were analyzed using GC-MS and TEM. The compositions of some aromatic compounds changed noticeably when using a metal oxide species as the catalyst. The coexistence or dissolution of amorphous carbon and iron oxide was observed in char pyrolyzed at 800 °C with Fe3O4. Pyrolysis oil compositions changed remarkably when formed in the presence of a catalyst compared to that obtained from the uncatalyzed pyrolysis of wood meal. We observed a tendency toward an increase in the ratio of polyaromatic hydrocarbons in the pyrolysis oil composition after catalytic pyrolysis at 800 °C. Pyrolysis of biomass using pulse current heating and an adequate amount of catalyst is expected to yield a higher content of specific polyaromatic compounds.

  9. Crustal radiogenic heat production and the selective survival of ancient continental crust

    NASA Technical Reports Server (NTRS)

    Morgan, P.

    1985-01-01

    It is pointed out that the oldest terrestrial rocks have so far revealed no evidence of the impact phase of earth evolution. This observation suggests that processes other than impact were dominant at the time of stabilization of these units. However, a use of the oldest terrestrial rocks as a sample of the early terrestrial crust makes it necessary to consider the possibility that these rocks may represent a biased sample. In the present study, the global continental heat flow data set is used to provide further evidence that potassium, uranium, and thorium abundances are, on the average, low in surviving Archean crust relative to younger continental crust. An investigation is conducted of the implications of relatively low crustal radiogenic heat production to the stabilization of early continental crust, and possible Archean crustal stabilization models are discussed.

  10. Crustal radiogenic heat production and the selective survival of ancient continental crust

    NASA Technical Reports Server (NTRS)

    Morgan, P.

    1985-01-01

    It is pointed out that the oldest terrestrial rocks have so far revealed no evidence of the impact phase of Earth evolution. This observation suggests that processes other than impact were dominant at the time of stabilization of these units. However, a use of the oldest terrestrial rocks as a sample of the early terrestrial crust makes it necessary to consider the possibility that these rocks may represent a biased sample. In the present study, the global continental heat flow data set is used to provide further evidence that potassium, uranium, and thorium abundances are, on the average, low in surviving Archean crust relative to younger continental crust. An investigation is conducted of the implications of relatively low crustal radiogenic heat production to the stabilization of early continental crust, and possible Archean crustal stabilization models are discussed.

  11. Effect of Catalytic Pyrolysis Conditions Using Pulse Current Heating Method on Pyrolysis Products of Wood Biomass

    PubMed Central

    Honma, Sensho; Hata, Toshimitsu; Watanabe, Takashi

    2014-01-01

    The influence of catalysts on the compositions of char and pyrolysis oil obtained by pyrolysis of wood biomass with pulse current heating was studied. The effects of catalysts on product compositions were analyzed using GC-MS and TEM. The compositions of some aromatic compounds changed noticeably when using a metal oxide species as the catalyst. The coexistence or dissolution of amorphous carbon and iron oxide was observed in char pyrolyzed at 800°C with Fe3O4. Pyrolysis oil compositions changed remarkably when formed in the presence of a catalyst compared to that obtained from the uncatalyzed pyrolysis of wood meal. We observed a tendency toward an increase in the ratio of polyaromatic hydrocarbons in the pyrolysis oil composition after catalytic pyrolysis at 800°C. Pyrolysis of biomass using pulse current heating and an adequate amount of catalyst is expected to yield a higher content of specific polyaromatic compounds. PMID:25614894

  12. Effect of catalytic pyrolysis conditions using pulse current heating method on pyrolysis products of wood biomass.

    PubMed

    Honma, Sensho; Hata, Toshimitsu; Watanabe, Takashi

    2014-01-01

    The influence of catalysts on the compositions of char and pyrolysis oil obtained by pyrolysis of wood biomass with pulse current heating was studied. The effects of catalysts on product compositions were analyzed using GC-MS and TEM. The compositions of some aromatic compounds changed noticeably when using a metal oxide species as the catalyst. The coexistence or dissolution of amorphous carbon and iron oxide was observed in char pyrolyzed at 800 °C with Fe3O4. Pyrolysis oil compositions changed remarkably when formed in the presence of a catalyst compared to that obtained from the uncatalyzed pyrolysis of wood meal. We observed a tendency toward an increase in the ratio of polyaromatic hydrocarbons in the pyrolysis oil composition after catalytic pyrolysis at 800 °C. Pyrolysis of biomass using pulse current heating and an adequate amount of catalyst is expected to yield a higher content of specific polyaromatic compounds. PMID:25614894

  13. Effects of microwave heating on porous structure of regenerated powdered activated carbon used in xylose.

    PubMed

    Li, Wei; Wang, Xinying; Peng, Jinhui

    2014-01-01

    The regeneration of spent powdered activated carbons used in xylose decolourization by microwave heating was investigated. Effects of microwave power and microwave heating time on the adsorption capacity of regenerated activated carbons were evaluated. The optimum conditions obtained are as follows: microwave power 800W; microwave heating time 30min. Regenerated activated carbon in this work has high adsorption capacities for the amount of methylene blue of 16 cm3/0.1 g and the iodine number of 1000.06mg/g. The specific surface areas of fresh commercial activated carbon, spent carbon and regenerated activated carbon were calculated according to the Brunauer, Emmett and Teller method, and the pore-size distributions of these carbons were characterized by non-local density functional theory (NLDFT). The results show that the specific surface area and the total pore volume of regenerated activated carbon are 1064 m2/g and 1.181 mL/g, respectively, indicating the feasibility of regeneration of spent powdered activated carbon used in xylose decolourization by microwave heating. The results of surface fractal dimensions also confirm the results of isotherms and NLDFT.

  14. Effects of microwave heating on porous structure of regenerated powdered activated carbon used in xylose.

    PubMed

    Li, Wei; Wang, Xinying; Peng, Jinhui

    2014-01-01

    The regeneration of spent powdered activated carbons used in xylose decolourization by microwave heating was investigated. Effects of microwave power and microwave heating time on the adsorption capacity of regenerated activated carbons were evaluated. The optimum conditions obtained are as follows: microwave power 800W; microwave heating time 30min. Regenerated activated carbon in this work has high adsorption capacities for the amount of methylene blue of 16 cm3/0.1 g and the iodine number of 1000.06mg/g. The specific surface areas of fresh commercial activated carbon, spent carbon and regenerated activated carbon were calculated according to the Brunauer, Emmett and Teller method, and the pore-size distributions of these carbons were characterized by non-local density functional theory (NLDFT). The results show that the specific surface area and the total pore volume of regenerated activated carbon are 1064 m2/g and 1.181 mL/g, respectively, indicating the feasibility of regeneration of spent powdered activated carbon used in xylose decolourization by microwave heating. The results of surface fractal dimensions also confirm the results of isotherms and NLDFT. PMID:24645431

  15. Calorimetric Determinations of the Heat and Products of Detonation for Explosives: October 1961 to April 1982

    NASA Astrophysics Data System (ADS)

    Ornellas, D. L.

    1982-04-01

    This report is a compilation of heat-of-detonation and product-composition data obtained at Lawrence Livermore National Laboratory during the last 21 years. In each determination, a 25-g high-explosive charge was detonated in a bomb calorimeter; a complete calorimetric measurement was made in 1 to 2 h with a precision of 0.3%. Data were interpreted using thermodynamic and hydrodynamic computer calculations. For unconfined or lightly confined charges, the released energy is largely retained in the products, which are subsequently shocked considerably off the Chapman-Jouguet isentrope by reflections from the bomb wall. For heavily confined charges, the detonation energy is largely converted to kinetic and internal energy of the confining case, and the products expand with minimal reshock along the Chapman-Jouguet isentrope.

  16. Solar Radiation during Rewarming from Torpor in Elephant Shrews: Supplementation or Substitution of Endogenous Heat Production?

    PubMed Central

    Thompson, Michelle L.; Mzilikazi, Nomakwezi; Bennett, Nigel C.; McKechnie, Andrew E.

    2015-01-01

    Many small mammals bask in the sun during rewarming from heterothermy, but the implications of this behaviour for their energy balance remain little understood. Specifically, it remains unclear whether solar radiation supplements endogenous metabolic thermogenesis (i.e., rewarming occurs through the additive effects of internally-produced and external heat), or whether solar radiation reduces the energy required to rewarm by substituting (i.e, replacing) metabolic heat production. To address this question, we examined patterns of torpor and rewarming rates in eastern rock elephant shrews (Elephantulus myurus) housed in outdoor cages with access to either natural levels of solar radiation or levels that were experimentally reduced by means of shade cloth. We also tested whether acclimation to solar radiation availability was manifested via phenotypic flexibility in basal metabolic rate (BMR), non-shivering thermogenesis (NST) capacity and/or summit metabolism (Msum). Rewarming rates varied significantly among treatments, with elephant shrews experiencing natural solar radiation levels rewarming faster than conspecifics experiencing solar radiation levels equivalent to approximately 20% or 40% of natural levels. BMR differed significantly between individuals experiencing natural levels of solar radiation and conspecifics experiencing approximately 20% of natural levels, but no between-treatment difference was evident for NST capacity or Msum. The positive relationship between solar radiation availability and rewarming rate, together with the absence of acclimation in maximum non-shivering and total heat production capacities, suggests that under the conditions of this study solar radiation supplemented rather than substituted metabolic thermogenesis as a source of heat during rewarming from heterothermy. PMID:25853244

  17. Solar radiation during rewarming from torpor in elephant shrews: supplementation or substitution of endogenous heat production?

    PubMed

    Thompson, Michelle L; Mzilikazi, Nomakwezi; Bennett, Nigel C; McKechnie, Andrew E

    2015-01-01

    Many small mammals bask in the sun during rewarming from heterothermy, but the implications of this behaviour for their energy balance remain little understood. Specifically, it remains unclear whether solar radiation supplements endogenous metabolic thermogenesis (i.e., rewarming occurs through the additive effects of internally-produced and external heat), or whether solar radiation reduces the energy required to rewarm by substituting (i.e, replacing) metabolic heat production. To address this question, we examined patterns of torpor and rewarming rates in eastern rock elephant shrews (Elephantulus myurus) housed in outdoor cages with access to either natural levels of solar radiation or levels that were experimentally reduced by means of shade cloth. We also tested whether acclimation to solar radiation availability was manifested via phenotypic flexibility in basal metabolic rate (BMR), non-shivering thermogenesis (NST) capacity and/or summit metabolism (Msum). Rewarming rates varied significantly among treatments, with elephant shrews experiencing natural solar radiation levels rewarming faster than conspecifics experiencing solar radiation levels equivalent to approximately 20% or 40% of natural levels. BMR differed significantly between individuals experiencing natural levels of solar radiation and conspecifics experiencing approximately 20% of natural levels, but no between-treatment difference was evident for NST capacity or Msum. The positive relationship between solar radiation availability and rewarming rate, together with the absence of acclimation in maximum non-shivering and total heat production capacities, suggests that under the conditions of this study solar radiation supplemented rather than substituted metabolic thermogenesis as a source of heat during rewarming from heterothermy.

  18. Closeout Report for the Refractory Metal Accelerated Heat Pipe Life Test Activity

    NASA Technical Reports Server (NTRS)

    Martin, J.; Reid, R.; Stewart, E.; Hickman, R.; Mireles, O.

    2013-01-01

    With the selection of a gas-cooled reactor, this heat pipe accelerated life test activity was closed out and its resources redirected. The scope of this project was to establish the long-term aging effects on Mo-44.5%Re sodium heat pipes when subjected to space reactor temperature and mass fluences. To date, investigators have demonstrated heat pipe life tests of alkali metal systems up to .50,000 hours. Unfortunately, resources have not been available to examine the effect of temperature, mass fluence, or impurity level on corrosion or to conduct post-test forensic examination of heat pipes. The key objective of this effort was to establish a cost/time effective method to systematically test alkali metal heat pipes with both practical and theoretical benefits. During execution of the project, a heat pipe design was established, a majority of the laboratory test equipment systems specified, and operating and test procedures developed. Procurements for the heat pipe units and all major test components were underway at the time the stop work order was issued. An extremely important outcome was the successful fabrication of an annular wick from Mo-5%Re screen (the single, most difficult component to manufacture) using a hot isostatic pressing technique. This Technical Publication (TP) includes specifics regarding the heat pipe calorimeter water-cooling system, vendor design for the radio frequency heating system, possible alternative calorimeter designs, and progress on the vanadium equilibration technique. The methods provided in this TP and preceding project documentation would serve as a good starting point to rapidly implement an accelerated life test. Relevant test data can become available within months, not years, and destructive examination of the first life test heat pipe might begin within 6 months of test initiation. Final conclusions could be drawn in less than a quarter of the mission duration for a long-lived, fission-powered, deep space probe.

  19. Class and Home Problems. Identify-Solve-Broadcast Your Own Transport Phenomenon: Student-Created YouTube Videos to Foster Active Learning in Mass and Heat Transfer

    ERIC Educational Resources Information Center

    Wen, Fei; Khera, Eshita

    2016-01-01

    Despite the instinctive perception of mass and heat transfer principles in daily life, productive learning in this course continues to be one of the greatest challenges for undergraduate students in chemical engineering. In an effort to enhance student learning in classroom, we initiated an innovative active-learning method titled…

  20. Predictions and measurements of heat production and food and water requirements of Holstein calves in different environments

    SciTech Connect

    Gebremedhin, K.G.; Cramer, C.O.; Porter, W.P.

    1981-01-01

    Heat losses computed from respiratory gas analysis were used to determine animal food and water requirements. The specific heat production (keal kg-h) of Holstein calves were determined from continuously recording the respiratory gas exchange in an indirect calorimetric system. Growth rates varied by a factor of 30 over the measured temperature range for the same food investment.

  1. Evolution of the ONSEN retrotransposon family activated upon heat stress in Brassicaceae.

    PubMed

    Ito, Hidetaka; Yoshida, Takanori; Tsukahara, Sayuri; Kawabe, Akira

    2013-04-15

    A Ty1/Copia-like retrotransposon, ONSEN, is activated by heat stress in Arabidopsis thaliana, and its de novo integrations that were observed preferentially within genes implies its regulation of neighboring genes. Here we show that ONSEN related copies were found in most species of Brassicaceae, forming a cluster with each species in phylogenetic tree. Most copies were localized close to genes in Arabidopsis lyrata and Brassica rapa, suggesting conserved integration specificity of ONSEN family into genic or open chromatin. In addition, we found heat-induced transcriptional activation of ONSEN family in several species of Brassicaceae. These results suggest that ONSEN has conserved transcriptional activation promoted by environmental heat stress in some Brassicaceae species.

  2. Diabatic heating profiles over the continental convergence zone during the monsoon active spells

    NASA Astrophysics Data System (ADS)

    Chattopadhyay, Rajib; Sur, Sharmila; Joseph, Susmitha; Sahai, A. K.

    2013-07-01

    The present paper aims to bring out the robust common aspects of spatio-temporal evolution of diabatic heating during the monsoon intraseasonal active phases over the continental tropical convergence zone (CTCZ). The robustness of spatio-temporal features is determined by comparing the two state-of-the art reanalyses: NCEP Climate Forecast System reanalysis and Modern ERA Retrospective Analysis. The inter-comparison is based on a study period of 26 years (1984-2009). The study confirms the development of deep heating over the CTCZ region during the active phase and is consistent between the two datasets. However, the detailed temporal evolution of the vertical structure (e.g., vertical tilts) of heating differs at times. The most important common feature from both the datasets is the significant vertical redistribution of heating with the development of shallow (low level) heating and circulation over the CTCZ region 3-7 days after the peak active phase. The shallow circulation is found to be associated with increased vertical shear and relative vorticity over certain regions in the subcontinent. This increased vertical shear and relative vorticity in the lower levels could be crucial in the sustenance of rainfall after the peak active phase. Model experiments with linear dynamics affirm the role of shallow convection in increasing the lower level circulation as observed.

  3. Distribution of esterase activity in porcine ear skin, and the effects of freezing and heat separation.

    PubMed

    Lau, Wing Man; Ng, Keng Wooi; Sakenyte, Kristina; Heard, Charles M

    2012-08-20

    Porcine ear skin is widely used to study skin permeation and absorption of ester compounds, whose permeation and absorption profiles may be directly influenced by in situ skin esterase activity. Importantly, esterase distribution and activity in porcine ear skin following common protocols of skin handling and storage have not been characterised. Thus, we have compared the distribution and hydrolytic activity of esterases in freshly excised, frozen, heated and explanted porcine ear skin. Using an esterase staining kit, esterase activity was found to be localised in the stratum corneum and viable epidermis. Under frozen storage and a common heating protocol of epidermal sheet separation, esterase staining in the skin visibly diminished. This was confirmed by a quantitative assay using HPLC to monitor the hydrolysis of aspirin, in freshly excised, frozen or heated porcine ear skin. Compared to vehicle-only control, the rate of aspirin hydrolysis was approximately three-fold higher in the presence of freshly excised skin, but no different in the presence of frozen or heated skin. Therefore, frozen and heat-separated porcine ear skin should not be used to study the permeation of ester-containing permeants, in particular co-drugs and pro-drugs, whose hydrolysis or degradation can be modulated by skin esterases.

  4. Space shuttle/food system study. Volume 2, Appendix A: Active heating system-screening analysis. Appendix B: Reconstituted food heating techniques analysis

    NASA Technical Reports Server (NTRS)

    1974-01-01

    Technical data are presented which were used to evaluate active heating methods to be incorporated into the space shuttle food system design, and also to evaluate the relative merits and penalties associated with various approaches to the heating of rehydrated food during space flight. Equipment heating candidates were subject to a preliminary screening performed by a selection rationale process which considered the following parameters; (1) gravitational effect; (2) safety; (3) operability; (4) system compatibility; (5) serviceability; (6) crew acceptability; (7) crew time; (8) development risk; and (9) operating cost. A hot air oven, electrically heated food tray, and microwave oven were selected for further consideration and analysis. Passive, semi-active, and active food preparation approaches were also studied in an effort to determine the optimum method for heating rehydrated food. Potential complexity, cost, vehicle impact penalties, and palatability were considered in the analysis. A summary of the study results is provided along with cost estimates for each of the potential sytems

  5. Evaluation of thermal energy storage for the proposed Twin Cities District Heating system. [using cogeneration heat production and aquifiers for heat storage

    NASA Technical Reports Server (NTRS)

    Meyer, C. F.

    1980-01-01

    The technical and economic feasibility of incorporating thermal energy storage components into the proposed Twin Cities District heating project was evaluated. The technical status of the project is reviewed and conceptual designs of district heating systems with and without thermal energy storage were compared in terms of estimated capital requirements, fuel consumption, delivered energy cost, and environmental aspects. The thermal energy storage system is based on cogeneration and the storage of heat in aquifers.

  6. Practical considerations for maximizing heat production in a novel thermobrachytherapy seed prototype

    SciTech Connect

    Gautam, Bhoj; Warrell, Gregory; Shvydka, Diana; Ishmael Parsai, E.; Subramanian, Manny

    2014-02-15

    Purpose: A combination of hyperthermia and radiation in the treatment of cancer has been proven to provide better tumor control than radiation administered as a monomodality, without an increase in complications or serious toxicities. Moreover, concurrent administration of hyperthermia and radiation displays synergistic enhancement, resulting in greater tumor cell killing than hyperthermia and radiation delivered separately. The authors have designed a new thermobrachytherapy (TB) seed, which serves as a source of both radiation and heat for concurrent brachytherapy and hyperthermia treatments when implanted in solid tumors. This innovative seed, similar in size and geometry to conventional seeds, will have self-regulating thermal properties. Methods: The new seed's geometry is based on the standard BEST Model 2301{sup 125}I seed, resulting in very similar dosimetric properties. The TB seed generates heat when placed in an oscillating magnetic field via induction heating of a ferromagnetic Ni–Cu alloy core that replaces the tungsten radiographic marker of the standard Model 2301. The alloy composition is selected to undergo a Curie transition near 50 °C, drastically decreasing power production at higher temperatures and providing for temperature self-regulation. Here, the authors present experimental studies of the magnetic properties of Ni–Cu alloy material, the visibility of TB seeds in radiographic imaging, and the ability of seed prototypes to uniformly heat tissue to a desirable temperature. Moreover, analyses are presented of magnetic shielding and thermal expansion of the TB seed, as well as matching of radiation dose to temperature distributions for a short interseed distance in a given treatment volume. Results: Annealing the Ni–Cu alloy has a significant effect on its magnetization properties, increasing the sharpness of the Curie transition. The TB seed preserves the radiographic properties of the BEST 2301 seed in both plain x rays and CT

  7. Effects of heating, storage, and ultraviolet exposure on antimicrobial activity of garlic juice.

    PubMed

    Al-Waili, Noori S; Saloom, Khelod Y; Akmal, M; Al-Waili, Thia N; Al-Waili, Ali N; Al-Waili, Hamza; Ali, Amjed; Al-Sahlani, Karem

    2007-03-01

    This study was designed to investigate the effect of heating, storage, and ultraviolet exposure on antimicrobial activity of garlic juice and its bacteriocidal activity against common human pathogens. Antimicrobial activity of fresh garlic juice was tested against Escherichia coli, Staphylococcus aureus, Streptococcus hemolyticus B, S. hemolyticus A, Klebsiella sp., Shigella dysenteriae, and Candida albicans using the disc method. The dilution method was performed by addition of garlic juice to broth media to obtain 1-100% concentrations as vol/vol or wt/vol. Garlic juice was used after 24 hours of storage at 4 degrees C, heating to 100 degrees C for 5 minutes, 10 minutes, 30 minutes, and 60 minutes, heating to 80 degrees C for 60 minutes, and 4 hours of exposure to ultraviolet light. Re-culture of specimens taken from garlic-induced negative media was performed in fresh broth free of garlic juice. Results showed that all the isolates were sensitive to fresh garlic juice; the most sensitive was C. albicans, and the least sensitive was S. hemolyticus A. Heating to 100 degrees C for 30 and 60 minutes completely abolished the antimicrobial activity, while heating for 5 and 10 minutes, storage for 24 hours, and 4 hours of ultraviolet exposure decreased it. Garlic juice was bactericidal at concentrations of 5% and more. Thus garlic juice has marked antimicrobial activity that makes it a potential agent to be tested in clinical trials. The antimicrobial activity was compromised by storage and heating; therefore it is advisable to use fresh garlic and avoid boiling it for more than 5 minutes during cooking. PMID:17472490

  8. Using flowering and heat-loss models for improving greenhouse energy-use efficiency in annual bedding plant production

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In temperate climates, annual bedding plants are typically produced in heated greenhouses from late winter through early summer. Temperature, photoperiod, light intensity, and transplant date are commonly manipulated during commercial production so that plants are in flower for predetermined market ...

  9. Baroreflex modulation of sympathetic nerve activity to muscle in heat-stressed humans

    NASA Technical Reports Server (NTRS)

    Cui, Jian; Wilson, Thad E.; Crandall, Craig G.

    2002-01-01

    To identify whether whole body heating alters arterial baroreflex control of muscle sympathetic nerve activity (MSNA), MSNA and beat-by-beat arterial blood pressure were recorded in seven healthy subjects during acute hypotensive and hypertensive stimuli in both normothermic and heat stress conditions. Whole body heating significantly increased sublingual temperature (P < 0.01), MSNA (P < 0.01), heart rate (P < 0.01), and skin blood flow (P < 0.001), whereas mean arterial blood pressure did not change significantly (P > 0.05). During both normothermic and heat stress conditions, MSNA increased and then decreased significantly when blood pressure was lowered and then raised via intravenous bolus infusions of sodium nitroprusside and phenylephrine HCl, respectively. The slope of the relationship between MSNA and diastolic blood pressure during heat stress (-128.3 +/- 13.9 U x beats(-1) x mmHg(-1)) was similar (P = 0.31) with normothermia (-140.6 +/- 21.1 U x beats(-1) x mmHg(-1)). Moreover, no significant change in the slope of the relationship between heart rate and systolic blood pressure was observed. These data suggest that arterial baroreflex modulation of MSNA and heart rate are not altered by whole body heating, with the exception of an upward shift of these baroreflex curves to accommodate changes in these variables that occur with whole body heating.

  10. Update: Heat injuries, active component, U.S. Armed Forces, 2013.

    PubMed

    2014-03-01

    The number of active component service members treated for heat stroke in 2013 (n=324) was the lowest since 2010 (n=321). Incidence rates of heat stroke were higher among males, those younger than 20 years of age, Asian/Pacific Islanders, Marine Corps and Army members, recruit trainees, and service members in combat-specific occupations, compared to their respective counterparts. Fewer service members were treated for "other heat injuries" in 2013 (n=1,701) than in any other year of the 5-year surveillance period. In addition, there were fewer reportable medical events, ambulatory encounters, and hospitalizations for "other heat injuries" in 2013 than in any of the prior 4 years. The incidence rate of "other heat injuries" was higher among females than males and 304 percent higher among recruit trainees than among other enlisted members or officers. During 2009-2013, a total of 909 heat injury events occurred in Iraq/Afghanistan; 6.4 percent (n=58) of those events were due to heat stroke. PMID:24684615

  11. Update: Heat injuries, active component, U.S. Armed Forces, 2014.

    PubMed

    2015-03-01

    The incidence rate of heat stroke among active component service members in 2014 was slightly higher than in 2013 but similar to the rates in 2011 and 2012. Incidence rates of heat stroke were higher among males, those younger than 20 years of age, Asian/Pacific Islanders, Marine Corps and Army members, and service members in combat-specific occupations, compared to their respective counterparts. Fewer service members were treated for "other heat injuries" in 2014 (n=1,683) than in any other year of the 5-year surveillance period. In addition, there were fewer reportable medical events for "other heat injuries" in 2014 than in any of the prior 4 years. The incidence rate of "other heat injuries" was higher among females than males and was more than 6-fold higher among recruit trainees than among other enlisted members or officers. During 2010-2014, 851 diagnoses of heat injuries were documented as having occurred among service members serving in Iraq/Afghanistan; 7.1% (n=60) of those diagnoses were for heat stroke. PMID:25825930

  12. On the relationship between photospheric footpoint motions and coronal heating in solar active regions

    SciTech Connect

    Van Ballegooijen, A. A.; Asgari-Targhi, M.; Berger, M. A.

    2014-05-20

    Coronal heating theories can be classified as either direct current (DC) or alternating current (AC) mechanisms, depending on whether the coronal magnetic field responds quasi-statically or dynamically to the photospheric footpoint motions. In this paper we investigate whether photospheric footpoint motions with velocities of 1-2 km s{sup –1} can heat the corona in active regions, and whether the corona responds quasi-statically or dynamically to such motions (DC versus AC heating). We construct three-dimensional magnetohydrodynamic models for the Alfvén waves and quasi-static perturbations generated within a coronal loop. We find that in models where the effects of the lower atmosphere are neglected, the corona responds quasi-statically to the footpoint motions (DC heating), but the energy flux into the corona is too low compared to observational requirements. In more realistic models that include the lower atmosphere, the corona responds more dynamically to the footpoint motions (AC heating) and the predicted heating rates due to Alfvén wave turbulence are sufficient to explain the observed hot loops. The higher heating rates are due to the amplification of Alfvén waves in the lower atmosphere. We conclude that magnetic braiding is a highly dynamic process.

  13. Antioxidative activity of the polyphenols from the involucres of Castanea mollissima Blume and their mitigating effects on heat stress.

    PubMed

    Dong, S; Li, H; Gasco, L; Xiong, Y; Guo, K J; Zoccarato, I

    2015-05-01

    Polyphenols extracted from plants have multiple functions in animal production. To explore new sources of tannin-rich extracts, which have potential benefits for animal health, this study focused on the effects of polyphenolic extracts from involucres of Castanea mollissima Blume (PICB) on heat-stressed broilers. In vitro experiments were first performed using intestinal cryptlike epithelial cell line-6 (IEC-6) cells to evaluate the effects of PICB on cell proliferation and antioxidative parameters under normal and heat-stress conditions. Then in vivo experiments were carried out with 2 trials: in trial 1, 400 one-d-old male Arbor Acres (AA) broilers were randomly assigned to 5 groups (4 replicates/group, 20 chicks/replicate): group 1 was a normal control group fed the basic ration; groups 2 to 5 were fed the basic ration supplemented with 0.2% vitamin C and 0.2%, 0.3%, and 0.4% PICB, respectively. Trial 1 lasted 42 d, and growth performance was monitored every week. At the end of the trial, the chicks were sacrificed and sampled. In trial 2, 400 twenty-eight-d-old chicks were randomly assigned to 5 groups as described in trial 1. After 1 week of adaptation, heat stress was applied for 7 consecutive days. On days 3 and 7 of heat stress, the chicks were sacrificed and sampled. The results showed that PICB could stimulate IEC-6 cell proliferation and had strong in vitro antioxidant activity. PICB had no effect on the growth performance and carcass parameters of AA broilers in trial 1, whereas in trial 2, group 4 saw improved growth performance and antioxidant activity compared to the first three groups (P < 0.05). In conclusion, PICB had no effects on the growth performance of IEC-6 cells and AA broilers under normal conditions, whereas it could mitigate heat-stress effects on the growth performance and antioxidant activity of IEC-6 cells and AA broilers, implying that PICB could be used as a suitable additive to improve animal production under heat

  14. Collagenase Production by Endotoxin-Activated Macrophages

    PubMed Central

    Wahl, Larry M.; Wahl, Sharon M.; Mergenhagen, Stephan E.; Martin, George R.

    1974-01-01

    Peritoneal exudate macrophages, when exposed to bacterial lipopolysaccharide in culture, were found to produce collagenase (EC 3.4.24.3). This enzyme was not detected in extracts of the macrophages or in media from nonstimulated macrophage cultures. Lipidcontaining fractions of the lipopolysaccharide, including a glycolipid from the rough mutant of Salmonella minnesota (R595) and lipid A, were potent stimulators of collagenase production. The lipid-free polysaccharide fraction had no effect. Cycloheximide prevented the production of collagenase by endotoxin-treated macrophages, suggesting that it was newly synthesized. Images PMID:4372628

  15. Leishmania amazonensis: effects of heat shock on ecto-ATPase activity.

    PubMed

    Peres-Sampaio, Carlos Eduardo; de Almeida-Amaral, Elmo Eduardo; Giarola, Naira Ligia Lima; Meyer-Fernandes, José Roberto

    2008-05-01

    In this work we demonstrated that promastigotes of Leishmania amazonensis exhibit an Mg-dependent ecto-ATPase activity, which is stimulated by heat shock. The Mg-dependent ATPase activity of cells grown at 22 and 28 degrees C was 41.0+/-5.2 nmol Pi/h x 10(7)cells and 184.2+/-21.0 nmol Pi/h x 10(7)cells, respectively. When both promastigotes were pre-incubated at 37 degrees C for 2h, the ATPase activity of cells grown at 22 degrees C was increased to 136.4+/-10.6 nmol Pi/h x 10(7) whereas that the ATPase activity of cells grown at 28 degrees C was not modified by the heat shock (189.8+/-10.3 nmol Pi/h x 10(7)cells). It was observed that Km of the enzyme from cells grown at 22 degrees C (Km=980.2+/-88.6 microM) was the same to the enzyme from cells grown at 28 degrees C (Km=901.4+/-91.9 microM). In addition, DIDS (4,4'-diisothiocyanatostilbene 2,2'-disulfonic acid) and suramin, two inhibitors of ecto-ATPases, also inhibited similarly the ATPase activities from promastigotes grown at 22 and 28 degrees C. We also observed that cells grown at 22 degrees C exhibit the same ecto-phosphatase and ecto 3'- and 5'-nucleotidase activities than cells grown at 28 degrees C. Interestingly, cycloheximide, an inhibitor of protein synthesis, suppressed the heat-shock effect on ecto-ATPase activity of cells grown at 22 degrees C were exposed at 37 degrees C for 2h. A comparison between the stimulation of the Mg-dependent ecto-ATPase activity of virulent and avirulent promastigotes by the heat shock showed that avirulent promastigotes had a higher stimulation than virulent promastigotes after heat stress. PMID:18295760

  16. Oral vaccination with heat inactivated Mycobacterium bovis activates the complement system to protect against tuberculosis.

    PubMed

    Beltrán-Beck, Beatriz; de la Fuente, José; Garrido, Joseba M; Aranaz, Alicia; Sevilla, Iker; Villar, Margarita; Boadella, Mariana; Galindo, Ruth C; Pérez de la Lastra, José M; Moreno-Cid, Juan A; Fernández de Mera, Isabel G; Alberdi, Pilar; Santos, Gracia; Ballesteros, Cristina; Lyashchenko, Konstantin P; Minguijón, Esmeralda; Romero, Beatriz; de Juan, Lucía; Domínguez, Lucas; Juste, Ramón; Gortazar, Christian

    2014-01-01

    Tuberculosis (TB) remains a pandemic affecting billions of people worldwide, thus stressing the need for new vaccines. Defining the correlates of vaccine protection is essential to achieve this goal. In this study, we used the wild boar model for mycobacterial infection and TB to characterize the protective mechanisms elicited by a new heat inactivated Mycobacterium bovis vaccine (IV). Oral vaccination with the IV resulted in significantly lower culture and lesion scores, particularly in the thorax, suggesting that the IV might provide a novel vaccine for TB control with special impact on the prevention of pulmonary disease, which is one of the limitations of current vaccines. Oral vaccination with the IV induced an adaptive antibody response and activation of the innate immune response including the complement component C3 and inflammasome. Mycobacterial DNA/RNA was not involved in inflammasome activation but increased C3 production by a still unknown mechanism. The results also suggested a protective mechanism mediated by the activation of IFN-γ producing CD8+ T cells by MHC I antigen presenting dendritic cells (DCs) in response to vaccination with the IV, without a clear role for Th1 CD4+ T cells. These results support a role for DCs in triggering the immune response to the IV through a mechanism similar to the phagocyte response to PAMPs with a central role for C3 in protection against mycobacterial infection. Higher C3 levels may allow increased opsonophagocytosis and effective bacterial clearance, while interfering with CR3-mediated opsonic and nonopsonic phagocytosis of mycobacteria, a process that could be enhanced by specific antibodies against mycobacterial proteins induced by vaccination with the IV. These results suggest that the IV acts through novel mechanisms to protect against TB in wild boar.

  17. Oral Vaccination with Heat Inactivated Mycobacterium bovis Activates the Complement System to Protect against Tuberculosis

    PubMed Central

    Garrido, Joseba M.; Aranaz, Alicia; Sevilla, Iker; Villar, Margarita; Boadella, Mariana; Galindo, Ruth C.; Pérez de la Lastra, José M.; Moreno-Cid, Juan A.; Fernández de Mera, Isabel G.; Alberdi, Pilar; Santos, Gracia; Ballesteros, Cristina; Lyashchenko, Konstantin P.; Minguijón, Esmeralda; Romero, Beatriz; de Juan, Lucía; Domínguez, Lucas; Juste, Ramón; Gortazar, Christian

    2014-01-01

    Tuberculosis (TB) remains a pandemic affecting billions of people worldwide, thus stressing the need for new vaccines. Defining the correlates of vaccine protection is essential to achieve this goal. In this study, we used the wild boar model for mycobacterial infection and TB to characterize the protective mechanisms elicited by a new heat inactivated Mycobacterium bovis vaccine (IV). Oral vaccination with the IV resulted in significantly lower culture and lesion scores, particularly in the thorax, suggesting that the IV might provide a novel vaccine for TB control with special impact on the prevention of pulmonary disease, which is one of the limitations of current vaccines. Oral vaccination with the IV induced an adaptive antibody response and activation of the innate immune response including the complement component C3 and inflammasome. Mycobacterial DNA/RNA was not involved in inflammasome activation but increased C3 production by a still unknown mechanism. The results also suggested a protective mechanism mediated by the activation of IFN-γ producing CD8+ T cells by MHC I antigen presenting dendritic cells (DCs) in response to vaccination with the IV, without a clear role for Th1 CD4+ T cells. These results support a role for DCs in triggering the immune response to the IV through a mechanism similar to the phagocyte response to PAMPs with a central role for C3 in protection against mycobacterial infection. Higher C3 levels may allow increased opsonophagocytosis and effective bacterial clearance, while interfering with CR3-mediated opsonic and nonopsonic phagocytosis of mycobacteria, a process that could be enhanced by specific antibodies against mycobacterial proteins induced by vaccination with the IV. These results suggest that the IV acts through novel mechanisms to protect against TB in wild boar. PMID:24842853

  18. Production of Heat Resistant Composite based on Siloxane Elastomer and Multiwall Carbon Nanotubes

    NASA Astrophysics Data System (ADS)

    Bessonov, I. V.; Karelina, N. V.; Kopitsyna, M. N.; Morozov, A. S.; Reznik, S. V.; Skidchenko, V. Yu.

    2016-02-01

    Development of a new generation of composite with unique thermal properties is an important task in the fields of science and technology where material is operated at high temperatures and exposure to a short-wave radiation. Recent studies show that carbon nanomaterials (fullerenes and carbon nanotubes) could improve the thermal, radiation and thermal-oxidative stability of the polymer matrix. In this article the development of a new heat resistant composite based on elastomer and carbon nanotubes (CNT) was performed and physicochemical properties of final product were evaluated.

  19. Initial heats of H{sub 2}S adsorption on activated carbons: Effect of surface features

    SciTech Connect

    Bagreev, A.; Adib, F.; Bandosz, T.J.

    1999-11-15

    The sorption of hydrogen sulfide was studied on activated carbons of various origins by means of inverse gas chromatography at infinite dilution. The conditions of the experiment were dry and anaerobic. Prior to the experiments the surface of some carbon samples was oxidized using either nitric acid or ammonium persulfate. Then the structural parameters of carbons were evaluated from the sorption of nitrogen. From the IGC experiments at various temperatures, heats of adsorption were calculated. The results showed that the heat of H{sub 2}S adsorption under dry anaerobic conditions does not depend on surface chemistry. The dependence of the heat of adsorption on the characteristic energy of nitrogen adsorption calculated from the Dubinin-Raduskevich equation was found. This correlation can be used to predict the heat of H{sub 2}S adsorption based on the results obtained from nitrogen adsorption.

  20. Structural and preliminary thermal performance testing of a pressure activated contact heat exchanger

    NASA Technical Reports Server (NTRS)

    Lee, C. Y.; Christian, E. L.; Wohlwend, J. W.; Parish, R. C.

    1987-01-01

    A contact heat exchanger concept is being developed for use onboard Space Station as an interface device between external thermal bus and pressurized modules. The concept relies on mechanical contact activated by the fluid pressure inside thin-walled tubes. Structural testings were carried out to confirm the technology feasibility of using such thin-walled tubes. The test results also verified the linear elastic stress analysis which was used to predict the tube mechanical behaviors. A preliminary thermal testing was also performed with liquid Freon-11 flowing inside tubes and heat being supplied by electrical heating from the bottom of the contact heat exchanger baseplate. The test results showed excellent agreement of test data with analytical prediction for all thermal resistances except for the two-phase flow characteristics. Testing with two-phase flow inside tubes will, however, be performed on the NASA-JSC test bed.

  1. "Hot" Non-flaring Plasmas in Active Region Cores Heated by Single Nanoflares

    NASA Astrophysics Data System (ADS)

    Barnes, Will Thomas; Cargill, Peter; Bradshaw, Stephen

    2016-05-01

    We use hydrodynamic modeling tools, including a two-fluid development of the EBTEL code, to investigate the properties expected of "hot" (i.e. between 106.7 and 107.2 K) non-flaring plasmas due to nanoflare heating in active regions. Here we focus on single nanoflares and show that while simple models predict an emission measure distribution extending well above 10 MK that is consistent with cooling by thermal conduction, many other effects are likely to limit the existence and detectability of such plasmas. These include: differential heating between electrons and ions, ionization non-equilibrium and, for short nanoflares, the time taken for the coronal density to increase. The most useful temperature range to look for this plasma, often called the "smoking gun" of nanoflare heating, lies between 1 MK and 10 MK. Signatures of the actual heating may be detectable in some instances.

  2. Modelling nanoflares in active regions and implications for coronal heating mechanisms.

    PubMed

    Cargill, P J; Warren, H P; Bradshaw, S J

    2015-05-28

    Recent observations from the Hinode and Solar Dynamics Observatory spacecraft have provided major advances in understanding the heating of solar active regions (ARs). For ARs comprising many magnetic strands or sub-loops heated by small, impulsive events (nanoflares), it is suggested that (i) the time between individual nanoflares in a magnetic strand is 500-2000 s, (ii) a weak 'hot' component (more than 10(6.6) K) is present, and (iii) nanoflare energies may be as low as a few 10(23) ergs. These imply small heating events in a stressed coronal magnetic field, where the time between individual nanoflares on a strand is of order the cooling time. Modelling suggests that the observed properties are incompatible with nanoflare models that require long energy build-up (over 10 s of thousands of seconds) and with steady heating. PMID:25897093

  3. Modelling nanoflares in active regions and implications for coronal heating mechanisms

    PubMed Central

    Cargill, P. J.; Warren, H. P.; Bradshaw, S. J.

    2015-01-01

    Recent observations from the Hinode and Solar Dynamics Observatory spacecraft have provided major advances in understanding the heating of solar active regions (ARs). For ARs comprising many magnetic strands or sub-loops heated by small, impulsive events (nanoflares), it is suggested that (i) the time between individual nanoflares in a magnetic strand is 500–2000 s, (ii) a weak ‘hot’ component (more than 106.6 K) is present, and (iii) nanoflare energies may be as low as a few 1023 ergs. These imply small heating events in a stressed coronal magnetic field, where the time between individual nanoflares on a strand is of order the cooling time. Modelling suggests that the observed properties are incompatible with nanoflare models that require long energy build-up (over 10 s of thousands of seconds) and with steady heating. PMID:25897093

  4. Optimization of a one-step heat-inducible in vivo mini DNA vector production system.

    PubMed

    Nafissi, Nafiseh; Sum, Chi Hong; Wettig, Shawn; Slavcev, Roderick A

    2014-01-01

    While safer than their viral counterparts, conventional circular covalently closed (CCC) plasmid DNA vectors offer a limited safety profile. They often result in the transfer of unwanted prokaryotic sequences, antibiotic resistance genes, and bacterial origins of replication that may lead to unwanted immunostimulatory responses. Furthermore, such vectors may impart the potential for chromosomal integration, thus potentiating oncogenesis. Linear covalently closed (LCC), bacterial sequence free DNA vectors have shown promising clinical improvements in vitro and in vivo. However, the generation of such minivectors has been limited by in vitro enzymatic reactions hindering their downstream application in clinical trials. We previously characterized an in vivo temperature-inducible expression system, governed by the phage λ pL promoter and regulated by the thermolabile λ CI[Ts]857 repressor to produce recombinant protelomerase enzymes in E. coli. In this expression system, induction of recombinant protelomerase was achieved by increasing culture temperature above the 37°C threshold temperature. Overexpression of protelomerase led to enzymatic reactions, acting on genetically engineered multi-target sites called "Super Sequences" that serve to convert conventional CCC plasmid DNA into LCC DNA minivectors. Temperature up-shift, however, can result in intracellular stress responses and may alter plasmid replication rates; both of which may be detrimental to LCC minivector production. We sought to optimize our one-step in vivo DNA minivector production system under various induction schedules in combination with genetic modifications influencing plasmid replication, processing rates, and cellular heat stress responses. We assessed different culture growth techniques, growth media compositions, heat induction scheduling and temperature, induction duration, post-induction temperature, and E. coli genetic background to improve the productivity and scalability of our system

  5. Modelling Hydraulic and Thermal Responses in a Benchmark for Deep Geothermal Heat Production

    NASA Astrophysics Data System (ADS)

    Holzbecher, E.; Oberdorfer, P.

    2012-04-01

    Geothermal heat production from deep reservoirs (5000-7000 m) is currently examined within the collaborative research program "Geothermal Energy and High-Performance Drilling" (gebo), funded by the Ministry of Science and Culture of Lower Saxony (Germany) and Baker Hughes. The projects concern exploration and characterization of geothermal reservoirs as well as production. They are gathered in the four major topic fields: geosystem, drilling, materials, technical system. We present modelling of a benchmark set-up concerning the geothermal production itself. The benchmark model "Horstberg" was originally created by J. Löhken and is based on geological data, concerning the Horstberg site in Lower Saxony. The model region consists of a cube with a side length of 5 km, in which 13 geological layers are included. A fault zone splits the region into two parts with shifted layering. A well is implemented, reaching from the top to an optional depth crossing all layers including the fault zone. The original geological model was rebuilt and improved in COMSOL Multiphysics Version 4.2a. The heterogeneous and detailed configuration makes the model interesting for benchmarking hydrogeological and geothermal applications. It is possible to inject and pump at any level in the well and to study the hydraulic and thermal responses of the system. The hydraulic and thermal parameters can be varied, and groundwater flow can be introduced. Moreover, it is also possible to examine structural mechanical responses to changes in the stress field (which is not further examined here). The main purpose of the presented study is to examine the dynamical flow characteristics of a hydraulic high conductive zone (Detfurth) in connection to a high conductive fault. One example is the fluid injection in the Detfurth zone and production in the fault. The high conductive domains can provide a hydraulic connection between the well screens and the initiated flow circuit could be used for geothermal

  6. Microbial production of sensory-active miraculin.

    PubMed

    Ito, Keisuke; Asakura, Tomiko; Morita, Yuji; Nakajima, Ken-ichiro; Koizumi, Ayako; Shimizu-Ibuka, Akiko; Masuda, Katsuyoshi; Ishiguro, Masaji; Terada, Tohru; Maruyama, Jun-ichi; Kitamoto, Katsuhiko; Misaka, Takumi; Abe, Keiko

    2007-08-24

    Miraculin (MCL), a tropical fruit protein, is unique in that it has taste-modifying activity to convert sourness to sweetness, though flat in taste at neutral pH. To obtain a sufficient amount of MCL to examine the mechanism involved in this sensory event at the molecular level, we transformed Aspergillus oryzae by introducing the MCL gene. Transformants were expressed and secreted a sensory-active form of MCL yielding 2 mg/L. Recombinant MCL resembled native MCL in the secondary structure and the taste-modifying activity to generate sweetness at acidic pH. Since the observed pH-sweetness relation seemed to reflect the imidazole titration curve, suggesting that histidine residues might be involved in the taste-modifying activity. H30A and H30,60A mutants were generated using the A. oryzae-mediated expression system. Both mutants found to have lost the taste-modifying activity. The result suggests that the histidine-30 residue is important for the taste-modifying activity of MCL. PMID:17592723

  7. Survival of Helicobacter pylori in Turkish fermented sucuk and heat-treated sucuk during production.

    PubMed

    Guner, Ahmet; Kav, Kursat; Tekinsen, Kemal Kaan; Dogruer, Yusuf; Telli, Nihat

    2011-12-01

    The aim of this study was to investigate the survival of Helicobacter pylori during production of sucuk (Turkish fermented sausage). The sucuk mixture was inoculated with H. pylori ATCC 43504 to produce a final level in the mixture of ∼5 × 10(6) CFU/g. Samples in group I were fermented and dried traditionally at 22°C for 7 days. Samples in groups II and III were subjected to the traditional fermentation at 22°C for 3 days. After fermentation, group II samples were fermented and dried at 35°C for 4 days and group III samples were treated with heat until the core temperature reached 65°C. On the first day of fermentation, a 1-log reduction in H. pylori was found in all groups. The H. pylori levels in all groups increased by about 1 log CFU/g by the third day of fermentation and reached the inoculation level. On the fifth and seventh days of fermentation, no appreciable change occurred in the level of H. pylori in groups I and II. After heat treatment, the H. pylori levels were below the level of detection. These results suggest that H. pylori can grow during sucuk fermentation and that a heat treatment should be used during sucuk processing to destroy H. pylori. PMID:22186045

  8. Mutagenic activity of disinfection by-products.

    PubMed

    Cognet, L; Courtois, Y; Mallevialle, J

    1986-11-01

    Data on raw water quality, disinfection treatment practices, and the resulting mutagenic properties of the treated water were compiled from pilot- and full-scale treatment experiments to evaluate that parameter which might produce variability in the results of a mutagenic study. Analysis of the data and comparison of treatment practices indicated that the measured mutagenic activity is strongly related to the characteristics of the organic matter in the raw water, the methodology used to sample and detect mutagens, the scale of the study both in terms of treatment flow and period of study, and the point at which and the conditions under which oxidants are added during treatment. Conclusions regarding disinfection systems in full-scale water treatment plants include the following: When raw water is pretreated and high concentrations of organics are present in the raw water, both ozonation and chlorination increased mutagenic activity. However, no significant difference in mutagenicity was found between the two oxidants. Both in the case of a nitrified groundwater and a clarified surface water, the mutagenic activity of the water after ozonation was related to its mutagenic activity before ozonation. With ozonation, mutagenic activity decreased after granular activated carbon (GAC) filtration. Thus, when GAC filtration follows ozone disinfection, early addition of oxidants may not be deleterious to the finished water quality. When chlorine or chlorine dioxide is added after GAC filtration, chlorine dioxide was found to produce a less mutagenic water than chlorine. Although these conclusions suggest means of controlling mutagenic activity during treatment, it must be stressed that the measurement of mutagenicity is a presumptive index of contamination level.

  9. Radiogenic Heat Production in the Gölcük Caldera and Direkli, Isparta Angle (Southwest Anatolia)

    NASA Astrophysics Data System (ADS)

    Ayten Uyanık, Nurten; Öncü, Ziya; Akkurt, İskender

    2016-04-01

    The radiogenic heat is one of the important parameter due to the radioactivity has existed since beginning of universe as prediction of Big-Bang theory. In this study the radiogenic heat production of the Gölcük caldera and Direkli fields of the Isparta-Turkey, has been investigated. Total of 1390 data were obtained in the study area. The study area is included of the Gölcük volcanism and its around that is located in Isparta province of Turkey's Mediterranean region. The Gölcük volcanism is a young volcanism. Around this volcanism the andesite, trachy andesite, tuff, pumice and such a geological units is available. The data were collected using in-situ measurements with gamm-ray spectrometer. These measurements were covered natural radioactive elements (Uranium U, Thorium Th and Potassium K). Radiogenic heat production values were calculated using the literature relationships and in-situ measurement values of these radioactive elements. Radiogenic heat map of study area were obtained using radiogenic heat production values. In the map the red zone areas shows highest heat values while green zones areas of the map presents lowest heat values. Key words: Radioactive elements, radiogenic heat, map, Gölcük-Direkli(Isparta), Turkey

  10. Whole body heat stress attenuates baroreflex control of muscle sympathetic nerve activity during postexercise muscle ischemia

    PubMed Central

    Cui, Jian; Shibasaki, Manabu; Davis, Scott L.; Low, David A.; Keller, David M.; Crandall, Craig G.

    2009-01-01

    Both whole body heat stress and stimulation of muscle metabolic receptors activate muscle sympathetic nerve activity (MSNA) through nonbaroreflex pathways. In addition to stimulating muscle metaboreceptors, exercise has the potential to increase internal temperature. Although we and others report that passive whole body heating does not alter the gain of the arterial baroreflex, it is unknown whether increased body temperature, often accompanying exercise, affects baroreflex function when muscle metaboreceptors are stimulated. This project tested the hypothesis that whole body heating alters the gain of baroreflex control of muscle sympathetic nerve activity (MSNA) and heart rate during muscle metaboreceptor stimulation engaged via postexercise muscle ischemia (PEMI). MSNA, blood pressure (BP, Finometer), and heart rate were recorded from 11 healthy volunteers. The volunteers performed isometric handgrip exercise until fatigue, followed by 2.5 min of PEMI. During PEMI, BP was acutely reduced and then raised pharmacologically using the modified Oxford technique. This protocol was repeated two to three times when volunteers were normothermic, and again during heat stress (increase core temperature ∼ 0.7°C) conditions. The slope of the relationship between MSNA and BP during PEMI was less negative (i.e., decreased baroreflex gain) during whole body heating when compared with the normothermic condition (−4.34 ± 0.40 to −3.57 ± 0.31 units·beat−1·mmHg−1, respectively; P = 0.015). The gain of baroreflex control of heart rate during PEMI was also decreased during whole body heating (P < 0.001). These findings indicate that whole body heat stress reduces baroreflex control of MSNA and heart rate during muscle metaboreceptor stimulation. PMID:19213933

  11. DIAGNOSING THE TIME DEPENDENCE OF ACTIVE REGION CORE HEATING FROM THE EMISSION MEASURE. II. NANOFLARE TRAINS

    SciTech Connect

    Reep, J. W.; Bradshaw, S. J.; Klimchuk, J. A. E-mail: stephen.bradshaw@rice.edu

    2013-02-20

    The time dependence of heating in solar active regions can be studied by analyzing the slope of the emission measure distribution coolward of the peak. In a previous study we showed that low-frequency heating can account for 0% to 77% of active region core emission measures. We now turn our attention to heating by a finite succession of impulsive events for which the timescale between events on a single magnetic strand is shorter than the cooling timescale. We refer to this scenario as a 'nanoflare train' and explore a parameter space of heating and coronal loop properties with a hydrodynamic model. Our conclusions are (1) nanoflare trains are consistent with 86% to 100% of observed active region cores when uncertainties in the atomic data are properly accounted for; (2) steeper slopes are found for larger values of the ratio of the train duration {Delta} {sub H} to the post-train cooling and draining timescale {Delta} {sub C}, where {Delta} {sub H} depends on the number of heating events, the event duration and the time interval between successive events ({tau} {sub C}); (3) {tau} {sub C} may be diagnosed from the width of the hot component of the emission measure provided that the temperature bins are much smaller than 0.1 dex; (4) the slope of the emission measure alone is not sufficient to provide information about any timescale associated with heating-the length and density of the heated structure must be measured for {Delta} {sub H} to be uniquely extracted from the ratio {Delta} {sub H}/{Delta} {sub C}.

  12. An application of active surface heating for augmenting lift and reducing drag of an airfoil

    NASA Technical Reports Server (NTRS)

    Maestrello, Lucio; Badavi, Forooz F.; Noonan, Kevin W.

    1988-01-01

    Application of active control to separated flow on the RC(6)-08 airfoil at high angle of attack by localized surface heating is numerically simulated by integrating the compressible 2-D nonlinear Navier-Stokes equation solver. Active control is simulated by local modification of the temperature boundary condition over a narrow strip of the upper surface of the airfoil. Both mean and perturbed profiles are favorably altered when excited with the same natural frequency of the shear layer by moderate surface heating for both laminar and turbulent separation. The shear layer is found to be very sensitive to localized surface heating in the vicinity of the separation point. The excitation field at the surface sufficiently altered both the local as well as the global circulation to cause a significant increase in lift and reduction in drag.

  13. National commercial solar heating and cooling demonstration: purposes, program activities, and implications for future programs

    SciTech Connect

    Koontz, R.; Genest, M.; Bryant, B.

    1980-05-01

    The Solar Heating and Cooling Demonstration Act of 1974 created a set of activities to demonstrate the potential use of solar heating within a three-year period and of combined solar heating and cooling within a five-year period. This study assesses the Commercial Demonstration Program portion of the activity in terms of its stated goals and objectives. The primary data base was DOE contractor reports on commercial demonstration projects. It was concluded that the program did not provide data to support a positive decision for the immediate construction or purchase of commercial solar systems. However, the program may have contributed to other goals in the subsequent legislation; i.e., research and development information, stimulation of the solar industry, and more informed policy decisions.

  14. Active control of asymmetric vortical flows around cones using injection and heating

    NASA Technical Reports Server (NTRS)

    Kandil, Osama A.; Sharaf, Hazem H.; Liu, C. H.

    1992-01-01

    The effectiveness of certain active-control methods for asymmetric flows around circular cones is investigated by using computational solution of the unsteady, compressible full Navier-Stokes equations. Two main methods of active control which include flow injection and surface heating are used. For the flow-injection-control method, flow injection is used either in the normal direction to the surface or in the tangential direction to the surface. For the surface-heating-control method, the temperature of the cone surface is increased. The effectiveness of a hybrid method of flow control which combines normal injection with surface heating has also been studied. The Navier-Stokes equations, subjected to various surface boundary conditions, are solved by using an implicit, upwind, flux-difference splitting, finite-volume scheme for locally-conical flow solutions.

  15. The calcium-activated chloride channel anoctamin 1 acts as a heat sensor in nociceptive neurons.

    PubMed

    Cho, Hawon; Yang, Young Duk; Lee, Jesun; Lee, Byeongjoon; Kim, Tahnbee; Jang, Yongwoo; Back, Seung Keun; Na, Heung Sik; Harfe, Brian D; Wang, Fan; Raouf, Ramin; Wood, John N; Oh, Uhtaek

    2012-05-27

    Nociceptors are a subset of small primary afferent neurons that respond to noxious chemical, thermal and mechanical stimuli. Ion channels in nociceptors respond differently to noxious stimuli and generate electrical signals in different ways. Anoctamin 1 (ANO1 also known as TMEM16A) is a Ca(2+)-activated chloride channel that is essential for numerous physiological functions. We found that ANO1 was activated by temperatures over 44 °C with steep heat sensitivity. ANO1 was expressed in small sensory neurons and was highly colocalized with nociceptor markers, which suggests that it may be involved in nociception. Application of heat ramps to dorsal root ganglion (DRG) neurons elicited robust ANO1-dependent depolarization. Furthermore, knockdown or deletion of ANO1 in DRG neurons substantially reduced nociceptive behavior in thermal pain models. These results indicate that ANO1 is a heat sensor that detects nociceptive thermal stimuli in sensory neurons and possibly mediates nociception.

  16. Heat transfer measurements in ONERA supersonic and hypersonic wind tunnels using passive and active infrared thermography

    NASA Astrophysics Data System (ADS)

    Balageas, D.; Boscher, D.; Deom, A.; Gardette, G.

    Over the past few years, a major intellectual and technical investment has been made at ONERA to use data acquisition systems and data reduction procedures using an infrared camera as a detector under routine wind tunnel conditions. This allows a really quantitative mapping of heat transfer rate distributions on models in supersonic and hypersonic flows. Sufficient experience has now been acquired to allow us to give an overview of: (1) the systems and data reduction procedures developed for both passive and active methods; (2) typical results obtained on various configurations such as supersonic axisymmetrical flow around an ogival body (passive and active thermography), heat flux modulation in the reattachment zone of a flap in hypersonic regime, transitional heating on very slightly blunted spheroconical bodies in hypersonic flows, and materials testing in high-enthalpy hypersonic flow (passive thermography).

  17. A trans-Activation Domain in Yeast Heat Shock Transcription Factor Is Essential for Cell Cycle Progression during Stress

    PubMed Central

    Morano, Kevin A.; Santoro, Nicholas; Koch, Keith A.; Thiele, Dennis J.

    1999-01-01

    Gene expression in response to heat shock is mediated by the heat shock transcription factor (HSF), which in yeast harbors both amino- and carboxyl-terminal transcriptional activation domains. Yeast cells bearing a truncated form of HSF in which the carboxyl-terminal transcriptional activation domain has been deleted [HSF(1-583)] are temperature sensitive for growth at 37°C, demonstrating a requirement for this domain for sustained viability during thermal stress. Here we demonstrate that HSF(1-583) cells undergo reversible cell cycle arrest at 37°C in the G2/M phase of the cell cycle and exhibit marked reduction in levels of the molecular chaperone Hsp90. As in higher eukaryotes, yeast possesses two nearly identical isoforms of Hsp90: one constitutively expressed and one highly heat inducible. When expressed at physiological levels in HSF(1-583) cells, the inducible Hsp90 isoform encoded by HSP82 more efficiently suppressed the temperature sensitivity of this strain than the constitutively expressed gene HSC82, suggesting that different functional roles may exist for these chaperones. Consistent with a defect in Hsp90 production, HSF(1-583) cells also exhibited hypersensitivity to the Hsp90-binding ansamycin antibiotic geldanamycin. Depletion of Hsp90 from yeast cells wild type for HSF results in cell cycle arrest in both G1/S and G2/M phases, suggesting a complex requirement for chaperone function in mitotic division during stress. PMID:9858564

  18. Heat shock protein 70 and AMP-activated protein kinase contribute to 17-DMAG-dependent protection against heat stroke.

    PubMed

    Tsai, Yung-Chieh; Lam, Kwok-Keung; Peng, Yi-Jen; Lee, Yen-Mei; Yang, Chung-Yu; Tsai, Yi-Ju; Yen, Mao-Hsiung; Cheng, Pao-Yun

    2016-10-01

    Heat shock protein 70 (Hsp70) preconditioning induces thermotolerance, and adenosine monophosphate (AMP)-activated protein kinase (AMPK) plays a role in the process of autophagy. Here, we investigated whether 17-dimethylaminoethylamino-17-demethoxy-geldanamycin (17-DMAG) protected against heat stroke (HS) in rats by up-regulation of Hsp70 and phosphorylated AMPK (pAMPK). To produce HS, male Sprague-Dawley rats were placed in a chamber with an ambient temperature of 42°C. Physiological function (mean arterial pressure, heart rate and core temperature), hepatic and intestinal injury, inflammatory mediators and levels of Hsp70, pAMPK and light chain 3 (LC3B) in hepatic tissue were measured in HS rats or/and rats pre-treated with 17-DMAG. 17-DMAG pre-treatment significantly attenuated hypotension and organ dysfunction induced by HS in rats. The survival time during HS was also prolonged by 17-DMAG treatment. Hsp70 expression was increased, whereas pAMPK levels in the liver were significantly decreased in HS rats. Following pre-treatment with 17-DMAG, Hsp70 protein levels increased further, and pAMPK levels were enhanced. Treatment with an AMPK activator significantly increased the LC3BII/LC3BI ratio as a marker of autophagy in HS rats. Treatment with quercetin significantly suppressed Hsp70 and pAMPK levels and reduced the protective effects of 17-DMAG in HS rats. Both of Hsp70 and AMPK are involved in the 17-DMAG-mediated protection against HS. 17-DMAG may be a promising candidate drug in the clinical setting.

  19. Heat shock protein 70 and AMP-activated protein kinase contribute to 17-DMAG-dependent protection against heat stroke.

    PubMed

    Tsai, Yung-Chieh; Lam, Kwok-Keung; Peng, Yi-Jen; Lee, Yen-Mei; Yang, Chung-Yu; Tsai, Yi-Ju; Yen, Mao-Hsiung; Cheng, Pao-Yun

    2016-10-01

    Heat shock protein 70 (Hsp70) preconditioning induces thermotolerance, and adenosine monophosphate (AMP)-activated protein kinase (AMPK) plays a role in the process of autophagy. Here, we investigated whether 17-dimethylaminoethylamino-17-demethoxy-geldanamycin (17-DMAG) protected against heat stroke (HS) in rats by up-regulation of Hsp70 and phosphorylated AMPK (pAMPK). To produce HS, male Sprague-Dawley rats were placed in a chamber with an ambient temperature of 42°C. Physiological function (mean arterial pressure, heart rate and core temperature), hepatic and intestinal injury, inflammatory mediators and levels of Hsp70, pAMPK and light chain 3 (LC3B) in hepatic tissue were measured in HS rats or/and rats pre-treated with 17-DMAG. 17-DMAG pre-treatment significantly attenuated hypotension and organ dysfunction induced by HS in rats. The survival time during HS was also prolonged by 17-DMAG treatment. Hsp70 expression was increased, whereas pAMPK levels in the liver were significantly decreased in HS rats. Following pre-treatment with 17-DMAG, Hsp70 protein levels increased further, and pAMPK levels were enhanced. Treatment with an AMPK activator significantly increased the LC3BII/LC3BI ratio as a marker of autophagy in HS rats. Treatment with quercetin significantly suppressed Hsp70 and pAMPK levels and reduced the protective effects of 17-DMAG in HS rats. Both of Hsp70 and AMPK are involved in the 17-DMAG-mediated protection against HS. 17-DMAG may be a promising candidate drug in the clinical setting. PMID:27241357

  20. Dehydration, Heat Stroke, or Hyponatremia? The Recognition, Treatment, and Prevention of Hyponatremia Caused by High Exercise Outdoor Activities.

    ERIC Educational Resources Information Center

    Cochran, Brent

    Hyponatremia (severe sodium depletion) has symptoms similar to heat exhaustion and heat stroke and can easily be misdiagnosed. The number of wilderness users and extreme adventure activities has increased in recent years, and more cases are being diagnosed. Given that a 1993 study found that 1 in 10 cases of heat-related illnesses were…

  1. Pyrolysis and gasification of lignocellulosic solid wastes for activated-carbon production

    SciTech Connect

    Mackay, D.M.

    1981-01-01

    The production process under consideration was pyrolysis of raw solid-waste material (precursor) to form a carbonaceous char followed by activation, or expansion of the pore system of the char by gasification with carbon dioxide at 900/sup 0/C. Char yield was found to be determined by precursor composition (percent lignin, holocellulose, etc.) and pyrolysis heating rate. Both factors were found to exert their main influence on char yield during pyrolysis below 500/sup 0/C. Selected chars prepared by pyrolysis at the lower heating rates (1 and 15/sup 0/C/min) to 500/sup 0/, 700/sup 0/, and 900/sup 0/C were gasified for various lengths of time in a CO/sub 2/ atmosphere at 900/sup 0/C. Pore-volume analysis of the final products was performed by nitrogen adsorption 77K and mercury porosimetry. The rate of mass loss and development of the pore system during gasification was found to vary with prior pyrolysis conditions: e.g., low heating rate or longer exposure to high temperature during pyrolysis led to lower rate of gasification. However, the pore volume developed for a given mass loss due to gasification reactions was independent of prior pyrolysis conditions. The latter result was apparently due to the similarity of the pore systems present in the chars immediately prior to the onset of the gasification reactions, i.e. after the char had heated to the gasification temperature. Because the heating rate during pyrolysis below 500/sup 0/C was the critical factor controlling char yield at 900/sup 0/C, the final yield of activated carbon (i.e. gasified char) of a specified pore volume was also influenced mainly by the pyrolysis heating rate below 500/sup 0/C.

  2. Gas production and transport during bench-scale electrical resistance heating of water and trichloroethene

    NASA Astrophysics Data System (ADS)

    Hegele, P. R.; Mumford, K. G.

    2014-09-01

    The effective remediation of chlorinated solvent source zones using in situ thermal treatment requires successful capture of gas that is produced. Replicate electrical resistance heating experiments were performed in a thin bench-scale apparatus, where water was boiled and pooled dense non-aqueous phase liquid (DNAPL) trichloroethene (TCE) and water were co-boiled in unconsolidated silica sand. Quantitative light transmission visualization was used to assess gas production and transport mechanisms. In the water boiling experiments, nucleation, growth and coalescence of the gas phase into connected channels were observed at critical gas saturations of Sgc = 0.233 ± 0.017, which allowed for continuous gas transport out of the sand. In experiments containing a colder region above a target heated zone, condensation prevented the formation of steam channels and discrete gas clusters that mobilized into colder regions were trapped soon after discontinuous transport began. In the TCE-water experiments, co-boiling at immiscible fluid interfaces resulted in discontinuous gas transport above the DNAPL pool. Redistribution of DNAPL was also observed above the pool and at the edge of the vapor front that propagated upwards through colder regions. These results suggest that the subsurface should be heated to water boiling temperatures to facilitate gas transport from specific locations of DNAPL to extraction points and reduce the potential for DNAPL redistribution. Decreases in electric current were observed at the onset of gas phase production, which suggests that coupled electrical current and temperature measurements may provide a reliable metric to assess gas phase development.

  3. Heat Production and Energy Efficiency of Broilers Infected With Necrotic Enteritis.

    PubMed

    M'Sadeq, Shawkat A; Wu, Shu-Biao; Choct, Mingan; Swick, Robert A

    2016-03-01

    Necrotic enteritis (NE) in poultry is the most important bacterial disease in terms of economic losses. The present study was conducted to evaluate the effect of an experimental challenge with necrotic enteritis on respiration and heat production in birds pretreated with dietary acylated starch or antibiotics (AB) zinc bacitracin (50 mg/kg) plus salinomycin (60 mg/kg). In total, 48 1-day-old Ross 308 male broilers were assigned to floor pens until day 10. On day 11, birds were randomly placed into 16 calorimetric chambers with four replicates of three birds per treatment. Treatments were: control, AB, acetylated high-amylose maize starch (SA), or butyrylated high-amylose maize starch (SB). Birds were NE challenged by inoculation with 5000 sporulated oocysts each of Eimeria maxima and Eimeria acervulina and 2500 sporulated oocysts of Eimeria brunetti on day 9 and Clostridium perfringens (3.8 × 10(8) colony-forming units) on day 14. The results showed that heat production (HP), respiratory quotient (RQ), heat increment, weight gain (WG), feed intake (FI), and livability (LV) of birds fed control, SA, and SB diets were lower than birds fed AB at 19 and 42 hr postinoculation (P < 0.05). At 65 hr postchallenge, increased FI and WG of birds were observed, indicating recovery from NE. During the entire period, from day 14 to day 17, birds fed control, SA, and SB had lower WG, FI, HP, RQ, metabolizable energy intake (MEI), and metabolizable energy (P < 0.01) than those fed AB. The data demonstrate that Eimeria sp. and C. perfringens challenge reduces growth performance, HP, RQ, metabolizable energy, and MEI of birds fed control, SA, and SB but not AB diets.

  4. Gas production and transport during bench-scale electrical resistance heating of water and trichloroethene.

    PubMed

    Hegele, P R; Mumford, K G

    2014-09-01

    The effective remediation of chlorinated solvent source zones using in situ thermal treatment requires successful capture of gas that is produced. Replicate electrical resistance heating experiments were performed in a thin bench-scale apparatus, where water was boiled and pooled dense non-aqueous phase liquid (DNAPL) trichloroethene (TCE) and water were co-boiled in unconsolidated silica sand. Quantitative light transmission visualization was used to assess gas production and transport mechanisms. In the water boiling experiments, nucleation, growth and coalescence of the gas phase into connected channels were observed at critical gas saturations of Sgc=0.233±0.017, which allowed for continuous gas transport out of the sand. In experiments containing a colder region above a target heated zone, condensation prevented the formation of steam channels and discrete gas clusters that mobilized into colder regions were trapped soon after discontinuous transport began. In the TCE-water experiments, co-boiling at immiscible fluid interfaces resulted in discontinuous gas transport above the DNAPL pool. Redistribution of DNAPL was also observed above the pool and at the edge of the vapor front that propagated upwards through colder regions. These results suggest that the subsurface should be heated to water boiling temperatures to facilitate gas transport from specific locations of DNAPL to extraction points and reduce the potential for DNAPL redistribution. Decreases in electric current were observed at the onset of gas phase production, which suggests that coupled electrical current and temperature measurements may provide a reliable metric to assess gas phase development. PMID:25084057

  5. Productivity and energy partition of late lactation dairy cows during heat exposure.

    PubMed

    Kim, Kyoung Hoon; Kim, Do-Hyung; Oh, Young-Kyoon; Lee, Sung-Sill; Lee, Hyun-Jeong; Kim, Dong-Woon; Seol, Yong-Joo; Kimura, Nobuhiro

    2010-02-01

    Three late-lactation Holstein cows were used to determine the effects of environmental temperature on performance and energy partitioning. Each cow was housed in a respiratory chamber for 30 consecutive days and exposed to three different conditions of environmental temperature: (i) 20 degrees C and 20 degrees C (20 degrees C), (ii) 25 degrees C and 20 degrees C (25 degrees C), (iii) 30 degrees C and 25 degrees C (30 degrees C) during the day and night, respectively. The temperature was switched in an interval of 10 days. Humidity in the chamber was maintained at 55-65% through the entire experimental period. The daily mean as well as morning and evening rectal temperatures of Holstein cows increased linearly (P < 0.05) as chamber temperature increased. There was a significant linear reduction in dry matter (DM) intake (P < 0.05) and an increase in DM digestibility (P < 0.05). The response in milk yield, however, was not affected by heat stress. There were no significant differences among treatments for intake energy, heat production, net energy for lactation and net energy for gain. This results of this study disagreed with the assumption that late lactation cows gave priority to increasing body tissue at the expense of milk production under thermal stress.

  6. Heat production in cold and long scotophase acclimated and winter acclimatized rodents

    NASA Astrophysics Data System (ADS)

    Haim, A.; Fourie, F. Le R.

    1980-09-01

    Heat production by means of oxygen consumptionVo2 (at Ta = 6° C, 25° C, 30° C, and 32° C) and non-shivering thermogenesis (NST) were studied in individuals of a diurnal rodent ( Rhabdomys pumilio) and a nocturnal rodent ( Praomys natalensis). The studied mice were acclimated to cold at Ta=8°C with a photoperiod of LD 12:12. On the otherhand specimens of these two species were acclimated at Ta=25°C with a long scotophase LD8:16. The results were compared with a control group (Ta=25° C, LD 12:12) and winter acclimatized individuals of both species.Vo2 in cold acclimated mice of both species was significantly increased when compared to the control group and was even higher than the winter acclimatized group when measured below the lower critical temperature. Long scotophase acclimated mice of both species also increased their oxygen consumption significantly when compared to the control group. NST was significantly increased in long scotophase acclimated mice from both species when compared to the control group. The results of this study indicate that the effects of acclimation to long scotophase are similar to those of cold acclimation. As changes in photoperiod are regular, it may be assumed that heat production mechanisms in acclimatization to winter will respond to changes in photoperiodicity.

  7. Vertical Profiles of Latent Heat Release over the Global Tropics using TRMM Rainfall Products from December 1997 to November 2002

    NASA Technical Reports Server (NTRS)

    Tao, W.-K.; Lang, S.; Simpson, J.; Meneghini, R.; Halverson, J.; Johnson, R.; Adler, R.

    2003-01-01

    NASA Tropical Rainfall Measuring Mission (TRMM) precipitation radar (PR) derived rainfall information will be used to estimate the four-dimensional structure of global monthly latent heating and rainfall profiles over the global tropics from December 1997 to November 2000. Rainfall, latent heating and radar reflectivity structures between El Nino (DJF 1997-98) and La Nina (DJF 1998-99) will be examined and compared. The seasonal variation of heating over various geographic locations (i.e., oceanic vs continental, Indian ocean vs west Pacific, Africa vs. S. America ) will also be analyzed. In addition, the relationship between rainfall, latent heating (maximum heating level), radar reflectivity and SST is examined and will be presented in the meeting. The impact of random error and bias in stratiform percentage estimates from PR on latent heating profiles is studied and will also be presented in the meeting. The Goddard Cumulus Ensemble Model is being used to simulate various mesoscale convective systems that developed in different geographic locations. Specifically, the model estimated rainfall, radar reflectivity and latent heating profiles will be compared to observational data collected from TRMM field campaigns over the South China Sea in 1998 (SCSMEX), Brazil in 1999 (TRMM-LBA), and the central Pacific in 1999 (KWAJEX). Sounding diagnosed heating budgets and radar reflectivity from these experiments can provide the means to validate (heating product) as well as improve the GCE model. Review of other latent heating algorithms will be discussed in the workshop.

  8. Monitoring ground-surface heating during expansion of the Casa Diablo production well field at Mammoth Lakes, California

    USGS Publications Warehouse

    Bergfeld, D.; Vaughan, R. Greg; Evans, William C.; Olsen, Eric

    2015-01-01

    The Long Valley hydrothermal system supports geothermal power production from 3 binary plants (Casa Diablo) near the town of Mammoth Lakes, California. Development and growth of thermal ground at sites west of Casa Diablo have created concerns over planned expansion of a new well field and the associated increases in geothermal fluid production. To ensure that all areas of ground heating are identified prior to new geothermal development, we obtained high-resolution aerial thermal infrared imagery across the region. The imagery covers the existing and proposed well fields and part of the town of Mammoth Lakes. Imagery results from a predawn flight on Oct. 9, 2014 readily identified the Shady Rest thermal area (SRST), one of two large areas of ground heating west of Casa Diablo, as well as other known thermal areas smaller in size. Maximum surface temperatures at 3 thermal areas were 26–28 °C. Numerous small areas with ground temperatures >16 °C were also identified and slated for field investigations in summer 2015. Some thermal anomalies in the town of Mammoth Lakes clearly reflect human activity.Previously established projects to monitor impacts from geothermal power production include yearly surveys of soil temperatures and diffuse CO2 emissions at SRST, and less regular surveys to collect samples from fumaroles and gas vents across the region. Soil temperatures at 20 cm depth at SRST are well correlated with diffuse CO2 flux, and both parameters show little variation during the 2011–14 field surveys. Maximum temperatures were between 55–67 °C and associated CO2 discharge was around 12–18 tonnes per day. The carbon isotope composition of CO2 is fairly uniform across the area ranging between –3.7 to –4.4 ‰. The gas composition of the Shady Rest fumarole however has varied with time, and H2S concentrations in the gas have been increasing since 2009.

  9. Trypanosoma cruzi: effects of heat shock on ecto-ATPase activity.

    PubMed

    Giarola, Naira Lígia Lima; de Almeida-Amaral, Elmo Eduardo; Collopy-Júnior, Itallo; Fonseca-de-Souza, André Luiz; Majerowicz, David; Paes, Lisvane Silva; Gondim, Katia C; Meyer-Fernandes, José Roberto

    2013-04-01

    In this work, we demonstrate that Trypanosoma cruzi Y strain epimastigotes exhibit Mg2+-dependent ecto-ATPase activity that is stimulated by heat shock. When the epimastigotes were incubated at 37°C for 2h, the ecto-ATPase activity of the cells was 43.95±0.97 nmol Pi/h×10(7) cells, whereas the ecto-ATPase activity of cells that were not exposed to heat shock stress was 16.97±0.30 nmol Pi/h×10(7) cells. The ecto-ATPase activities of cells, that were exposed or not exposed to heat shock stress had approximately the same Km values (2.25±0.26 mM ATP and 1.55±0.23 mM ATP, respectively) and different Vmax values. The heat-shocked cells had higher Vmax values (54.38±3.07 nmol Pi/h×10(7) cells) than the cells that were not exposed to heat shock (19.38±1.76 nmol Pi/h×10(7) cells). We also observed that the ecto-phosphatase and ecto-5'nucleotidase activities of cells that had been incubated at 28°C or 37°C were the same. Interestingly, cycloheximide, an inhibitor of protein synthesis, suppressed the heat shock effect of ecto-ATPase activity on T. cruzi. The Mg2+-dependent ecto-ATPase activity from the Y strain (high virulence) was approximately 2-fold higher than that of Dm28c (a clone with low virulence). In addition, these two strains presented different responses to heat shock with regard to their ecto-ATPase activities; Y strain epimastigotes had a stimulation of 2.52-fold while the Dm28c strain had a 1.71-fold stimulation. In this context, the virulent trypomastigote form of T. cruzi, Dm28c, had an ecto-ATPase activity that was more than 7-fold higher (66.67±5.98 nmol Pi/h×10(7) cells) than that of the insect epimastigote forms (8.91±0.76 nmol Pi/h×10(7) cells). This difference increased to approximately 10-fold when both forms were subjected to heat shock stress (181.14±16.48 nmol Pi/h×10(7) cells for trypomastigotes and 16.71±1.17 nmol Pi/h×10(7) cells for epimastigotes at 37°C). The ecto-ATPase activity of a plasma membrane-enriched fraction

  10. Finger heat flux/temperature as an indicator of thermal imbalance with application for extravehicular activity.

    PubMed

    Koscheyev, Victor S; Leon, Gloria R; Coca, Aitor

    2005-11-01

    The designation of a simple, non-invasive, and highly precise method to monitor the thermal status of astronauts is important to enhance safety during extravehicular activities (EVA) and onboard emergencies. Finger temperature (Tfing), finger heat flux, and indices of core temperature (Tc) [rectal (Tre), ear canal (Tec)] were assessed in 3 studies involving different patterns of heat removal/insertion from/to the body by a multi-compartment liquid cooling/warming garment (LCWG). Under both uniform and nonuniform temperature conditions on the body surface, Tfing and finger heat flux were highly correlated with garment heat flux, and also highly correlated with each other. Tc responses did not adequately reflect changes in thermal balance during the ongoing process of heat insertion/removal from the body. Overall, Tfing/finger heat flux adequately reflected the initial destabilization of thermal balance, and therefore appears to have significant potential as a useful index for monitoring and maintaining thermal balance and comfort in extreme conditions in space as well as on Earth.

  11. Update Heat injuries, active component, U.S. Army, Navy, Air Force, and Marine Corps, 2015.

    PubMed

    2016-03-01

    The incidence rate of heat stroke among active component members of the U.S. Army, Navy, Air Force, and Marine Corps in 2015 was higher than rates in the previous 4 years. Incidence rates of heat stroke were higher among males, those younger than 20 years of age, Asian/Pacific Islanders, Marine Corps and Army members, and service members in combat-specific occupations, compared to their respective counterparts. More service members were treated for "other heat injuries" in 2015 (n=1,933) than in either of the previous 2 years. The incidence rate of "other heat injuries" was higher among females than males and rates were highest among service members younger than 20 years of age, among Army and Marine Corps members, among recruit trainees, and among service members in combat-specific occupations. During 2011-2015, 720 diagnoses of heat injuries were documented among service members serving in Iraq/Afghanistan; 6.9% (n=50) of those diagnoses were for heat stroke. PMID:27030928

  12. Finger heat flux/temperature as an indicator of thermal imbalance with application for extravehicular activity

    NASA Astrophysics Data System (ADS)

    Koscheyev, Victor S.; Leon, Gloria R.; Coca, Aitor

    2005-11-01

    The designation of a simple, non-invasive, and highly precise method to monitor the thermal status of astronauts is important to enhance safety during extravehicular activities (EVA) and onboard emergencies. Finger temperature ( Tfing), finger heat flux, and indices of core temperature ( Tc) [rectal ( Tre), ear canal ( Tec)] were assessed in 3 studies involving different patterns of heat removal/insertion from/to the body by a multi-compartment liquid cooling/warming garment (LCWG). Under both uniform and nonuniform temperature conditions on the body surface, Tfing and finger heat flux were highly correlated with garment heat flux, and also highly correlated with each other. Tc responses did not adequately reflect changes in thermal balance during the ongoing process of heat insertion/removal from the body. Overall, Tfing/finger heat flux adequately reflected the initial destabilization of thermal balance, and therefore appears to have significant potential as a useful index for monitoring and maintaining thermal balance and comfort in extreme conditions in space as well as on Earth.

  13. Sample Heat, Activity, Reactivity, and Dose Analysis for Safety Analysis of Irradiations in a Research Reactor.

    1987-12-01

    SHARDA is a program for assessing sample heating rates, activities produced and reactivity load caused while irradiating a small sample in a well thermalized research reactor like CIRUS. It estimates the sample cooling or lead shielding requirements to limit the gamma-ray dose rates due to the irradiated sample within permissible levels.

  14. Physical Activity in the Heat: Important Considerations to Keep Your Students Safe

    ERIC Educational Resources Information Center

    Roetert, E. Paul; Richardson, Cheryl L.; Bergeron, Michael F.

    2012-01-01

    Although July and August tend to be the warmest months of the year, the months leading up to summer as well as the months just following summer can also be quite warm or even very hot. In this article, the authors share some important information to help prepare physical educators for overseeing activities in the heat and, just as importantly, to…

  15. Croconaine rotaxane for acid activated photothermal heating and ratiometric photoacoustic imaging of acidic pH†

    PubMed Central

    Guha, Samit; Shaw, Gillian Karen; Mitcham, Trevor M.; Bouchard, Richard R.

    2015-01-01

    Absorption of 808 nm laser light by liposomes containing a pH sensitive, near-infrared croconaine rotaxane dye increases dramatically in weak acid. A stealth liposome composition permits acid activated, photothermal heating and also acts as an effective nanoparticle probe for ratiometric photoacoustic imaging of acidic pH in deep sample locations, including a living mouse. PMID:26502996

  16. Active PZT fibers: a commercial production process

    NASA Astrophysics Data System (ADS)

    Strock, Harold B.; Pascucci, Marina R.; Parish, Mark V.; Bent, Aaron A.; Shrout, Thomas R.

    1999-07-01

    Lead Zirconate Titanate (PZT) active fibers, from 80 to 250 micrometers in diameter, are produced for the AFOSR/DARPA funded Active Fiber Composites Consortium (AFCC) Program and commercial customers. CeraNova has developed a proprietary ceramics-based technology to produce PZT mono-filaments of the required purity, composition, straightness, and piezoelectric properties for use in active fiber composite structures. CeraNova's process begins with the extrusion of continuous lengths of mono-filament precursor fiber from a plasticized mix of PZT-5A powder. The care that must be taken to avoid mix contamination is described using illustrations form problems experiences with extruder wear and metallic contamination. Corrective actions are described and example microstructures are shown. The consequences of inadequate lead control are also shown. Sintered mono- filament mechanical strength and piezoelectric properties data approach bulk values but the validity of such a benchmark is questioned based on variable correlation with composite performance measures. Comb-like ceramic preform structures are shown that are being developed to minimize process and handling costs while maintaining the required mono-filament straightness necessary for composite fabrication. Lastly, actuation performance data are presented for composite structures fabricated and tested by Continuum Control Corporation. Free strain actuation in excess of 2000 microstrain are observed.

  17. Triple-shape effect in polymer-based composites by cleverly matching geometry of active component with heating method.

    PubMed

    Razzaq, M Y; Behl, M; Kratz, K; Lendlein, A

    2013-10-11

    A triple-shape effect is created for a segmented device consisting of an active component encapsulated in a highly flexible polymer network. Segments with the same composition but different interface areas can be recovered independently either at specific field strengths (Hsw ) during inductive heating, at a specific time during environmentally heating, or at different airflow during inductive heating at constant H. Herein the type of heating method regulates the sequence order.

  18. Effect of wind and solar radiation on metabolic heat production in a small desert rodent, Spermophilus tereticaudus.

    PubMed

    Wooden, K M; Walsberg, G E

    2000-03-01

    To understand better how complex interactions between environmental variables affect the energy balance of small diurnal animals, we studied the effects of the absence and presence of 950 W m(-)(2) simulated solar radiation combined with wind speeds ranging from 0. 25 to 1.00 m s(-)(1) on the metabolic rate and body temperature of the round-tailed ground squirrel Spermophilus tereticaudus. As wind speed increased from 0.25 to 1.00 m s(-)(1), metabolic heat production increased by 0.94 W in the absence of solar radiation and by 0.98 W in the presence of 950 W m(-)(2) simulated solar radiation. Exposure to simulated solar radiation reduced metabolic heat production by 0.68 W at a wind speed of 0.25 m s(-)(1), by 0.64 W at 0.50 m s(-)(1) and by 0.64 W at 1.00 m s(-)(1). Body temperature was significantly affected by environmental conditions, ranging from 32. 5 degrees C at a wind speed of 1.0 m s(-)(1) and no irradiance to 35. 6 degrees C at a wind speed of 0.50 m s(-)(1) with 950 W m(-)(2 )short-wave irradiance. In addition, several unusual findings resulted from this study. The coat of S. tereticaudus is very sparse, and the observed heat transfer of 5.68+/-0.37 W m(-)(2 ) degrees C(-)(1) (mean +/- s.e.m., N=11) is much higher than expected from either allometric equations or comparative studies with other rodents of similar mass. Solar heat gain was remarkably low, equalling only 10 % of intercepted radiation and suggesting a remarkably high regional thermal resistance at the tissue level. Animals remained normally active and alert at body temperatures as low as 32.5 degrees C. These findings suggest a unique combination of adaptations that allow S. tereticaudus to exploit a harsh desert environment. PMID:10667970

  19. Extracellular enzyme activities during cassava fermentation for 'fufu' production.

    PubMed

    Oyewole, O B; Odunfa, S A

    1992-01-01

    Amylase and pectin methyl esterase activities increased rapidly during the early period of the fermentation of cassava for 'fufu' production, attaining their peak activities after 12 and 24h, respectively. Cellulase activity was lower and approximately constant for most of the fermentation period.

  20. Heat shock modulates the subcellular localization, stability, and activity of HIPK2.

    PubMed

    Upadhyay, Mamta; Bhadauriya, Pratibha; Ganesh, Subramaniam

    2016-04-15

    The homeodomain-interacting protein kinase-2 (HIPK2) is a highly conserved serine/threonine kinase and is involved in transcriptional regulation. HIPK2 is a highly unstable protein, and is kept at a low level under normal physiological conditions. However, exposure of cells to physiological stress - such as hypoxia, oxidative stress, or UV damage - is known to stabilize HIPK2, leading to the HIPK2-dependent activation of p53 and the cell death pathway. Therefore HIPK2 is also known as a stress kinase and as a stress-activated pro-apoptotic factor. We demonstrate here that exposure of cells to heat shock results in the stabilization of HIPK2 and the stabilization is mediated via K63-linked ubiquitination. Intriguingly, a sub-lethal heat shock (42 °C, 1 h) results in the cytoplasmic localization of HIPK2, while a lethal heat shock (45 °C, 1 h) results in its nuclear localization. Cells exposed to the lethal heat shock showed significantly higher levels of the p53 activity than those exposed to the sub-lethal thermal stress, suggesting that both the level and the nuclear localization are essential for the pro-apoptotic activity of HIPK2 and that the lethal heat shock could retain the HIPK2 in the nucleus to promote the cell death. Taken together our study underscores the importance of HIPK2 in stress mediated cell death, and that the HIPK2 is a generic stress kinase that gets activated by diverse set of physiological stressors. PMID:26972256

  1. Heat shock modulates the subcellular localization, stability, and activity of HIPK2.

    PubMed

    Upadhyay, Mamta; Bhadauriya, Pratibha; Ganesh, Subramaniam

    2016-04-15

    The homeodomain-interacting protein kinase-2 (HIPK2) is a highly conserved serine/threonine kinase and is involved in transcriptional regulation. HIPK2 is a highly unstable protein, and is kept at a low level under normal physiological conditions. However, exposure of cells to physiological stress - such as hypoxia, oxidative stress, or UV damage - is known to stabilize HIPK2, leading to the HIPK2-dependent activation of p53 and the cell death pathway. Therefore HIPK2 is also known as a stress kinase and as a stress-activated pro-apoptotic factor. We demonstrate here that exposure of cells to heat shock results in the stabilization of HIPK2 and the stabilization is mediated via K63-linked ubiquitination. Intriguingly, a sub-lethal heat shock (42 °C, 1 h) results in the cytoplasmic localization of HIPK2, while a lethal heat shock (45 °C, 1 h) results in its nuclear localization. Cells exposed to the lethal heat shock showed significantly higher levels of the p53 activity than those exposed to the sub-lethal thermal stress, suggesting that both the level and the nuclear localization are essential for the pro-apoptotic activity of HIPK2 and that the lethal heat shock could retain the HIPK2 in the nucleus to promote the cell death. Taken together our study underscores the importance of HIPK2 in stress mediated cell death, and that the HIPK2 is a generic stress kinase that gets activated by diverse set of physiological stressors.

  2. Thermoregulation of water foraging honeybees--balancing of endothermic activity with radiative heat gain and functional requirements.

    PubMed

    Kovac, Helmut; Stabentheiner, Anton; Schmaranzer, Sigurd

    2010-12-01

    Foraging honeybees are subjected to considerable variations of microclimatic conditions challenging their thermoregulatory ability. Solar heat is a gain in the cold but may be a burden in the heat. We investigated the balancing of endothermic activity with radiative heat gain and physiological functions of water foraging Apis mellifera carnica honeybees in the whole range of ambient temperatures (T(a)) and solar radiation they are likely to be exposed in their natural environment in Middle Europe. The mean thorax temperature (T(th)) during foraging stays was regulated at a constantly high level (37.0-38.5 °C) in a broad range of T(a) (3-30 °C). At warmer conditions (T(a)=30-39 °C) T(th) increased to a maximal level of 45.3 °C. The endothermic temperature excess (difference of T(body)-T(a) of living and dead bees) was used to assess the endogenously generated temperature elevation as a correlate of energy turnover. Up to a T(a) of ∼30 °C bees used solar heat gain for a double purpose: to reduce energetic expenditure and to increase T(th) by about 1-3 °C to improve force production of flight muscles. At higher T(a) they exhibited cooling efforts to get rid of excess heat. A high T(th) also allowed regulation of the head temperature high enough to guarantee proper function of the bees' suction pump even at low T(a). This shortened the foraging stays and this way reduced energetic costs. With decreasing T(a) bees also reduced arrival body weight and crop loading to do both minimize costs and optimize flight performance. PMID:20705071

  3. Thermoregulation of water foraging honeybees—Balancing of endothermic activity with radiative heat gain and functional requirements

    PubMed Central

    Kovac, Helmut; Stabentheiner, Anton; Schmaranzer, Sigurd

    2010-01-01

    Foraging honeybees are subjected to considerable variations of microclimatic conditions challenging their thermoregulatory ability. Solar heat is a gain in the cold but may be a burden in the heat. We investigated the balancing of endothermic activity with radiative heat gain and physiological functions of water foraging Apis mellifera carnica honeybees in the whole range of ambient temperatures (Ta) and solar radiation they are likely to be exposed in their natural environment in Middle Europe. The mean thorax temperature (Tth) during foraging stays was regulated at a constantly high level (37.0–38.5 °C) in a broad range of Ta (3–30 °C). At warmer conditions (Ta = 30–39 °C) Tth increased to a maximal level of 45.3 °C. The endothermic temperature excess (difference of Tbody − Ta of living and dead bees) was used to assess the endogenously generated temperature elevation as a correlate of energy turnover. Up to a Ta of ∼30 °C bees used solar heat gain for a double purpose: to reduce energetic expenditure and to increase Tth by about 1–3 °C to improve force production of flight muscles. At higher Ta they exhibited cooling efforts to get rid of excess heat. A high Tth also allowed regulation of the head temperature high enough to guarantee proper function of the bees’ suction pump even at low Ta. This shortened the foraging stays and this way reduced energetic costs. With decreasing Ta bees also reduced arrival body weight and crop loading to do both minimize costs and optimize flight performance. PMID:20705071

  4. Microbial biomass and activity in soils with different moisture content heated at high temperatures

    NASA Astrophysics Data System (ADS)

    Barreiro, Ana; Lombao, Alba; Martin, Angela; Cancelo-González, Javier; Carballas, Tarsy; Díaz-Raviña, Montserrat

    2015-04-01

    It is well known that soil properties determining the thermal transmissivity (moisture, texture, organic matter, etc.) and the duration and temperatures reached during soil heating are key factors driving the fire-induced changes in soil microbial communities. However, despite its interest, the information about this topic is scarce. The aim of the present study is to analyze, under laboratory conditions, the impact of the thermal shock (infrared lamps reaching temperatures of 100 °C, 200 °C and 400 °C) on microbial communities of three acid soils under different moisture level (0 %, 25 % and 50 % per soil volume). Soil temperature was measured with thermocouples and the impact of soil heating was evaluated by means of the analysis of the temperature-time curves calculating the maximum temperature reached (Tmax) and the degree-hours (GH) as an estimation of the amount of heat supplied to the samples (fire severity). The bacterial growth (leucine incorporation) and the total microbial biomass (PLFA) were measured immediately after the heating and one month after the incubation of reinoculated soils. The results showed clearly the importance of moisture level in the transmission of heat through the soil and hence in the further direct impact of high temperatures on microorganisms living in soil. In general, the values of microbial parameters analyzed were low, particularly immediately after soil heating at higher temperatures; the bacterial activity measurements (leucine incorporation technique) being more sensitive to detect the thermal shock showed than total biomass measurements (PLFA). After 1 month incubation, soil microbial communities tend to recover due to the proliferation of surviving population using as substrate the dead microorganisms (soil sterilization). Thus, time elapsed after the heating was found to be decisive when examining the relationships between the microbial properties and the soil heating parameters (GH, Tmax). Analysis of results also

  5. Tension and heat production during isometric contractions and shortening in the anterior byssus retractor muscle of Mytilus edulis.

    PubMed Central

    Gilbert, S H

    1978-01-01

    1. Tension and heat production were measured during phasic isometric contractions and isovelocity shortening in the anterior byssus retractor muscle (ABRM) of Mytilus edulis at 20 degrees C. 2. Isometric tension at lo was 550 +/- 40 mN/mm2 (S.D. for 173 observations in nine muscles), while the isometric maintenance heat rate was 1.0 +/- 0.2 mW/g wet wt. (S.D. for seventy-eight observations in eight muscles). 3. Isometric tension and heat production were measured as functions of muscle length over a range of 0.79--1.14 lo and were found to bear a linear relation to each other. 4. The force-velocity relation was determined in isovelocity releases imposed during tetanic stimulation and was found to fit the Hill equation with parameters alpha/Po = 0.07 +/- 0.01 and b/lo = 0.016 +/- 0.0007 sec-1 (S.E. from non-linear least-squares regression of the pooled data from seven experiments). 5. Heat production measured in the same experiments showed that shortening heat is produced with a shortening heat coefficient alpha/Po of 0.15. Shortening heat does not appear to be force-dependent, and separate experiments confirmed that it is a linear function of the amount of shortening. PMID:722564

  6. Effects of steam pretreatment and co-production with ethanol on the energy efficiency and process economics of combined biogas, heat and electricity production from industrial hemp

    PubMed Central

    2013-01-01

    Background The study presented here has used the commercial flow sheeting program Aspen Plus™ to evaluate techno-economic aspects of large-scale hemp-based processes for producing transportation fuels. The co-production of biogas, district heat and power from chopped and steam-pretreated hemp, and the co-production of ethanol, biogas, heat and power from steam-pretreated hemp were analysed. The analyses include assessments of heat demand, energy efficiency and process economics in terms of annual cash flows and minimum biogas and ethanol selling prices (MBSP and MESP). Results Producing biogas, heat and power from chopped hemp has the highest overall energy efficiency, 84% of the theoretical maximum (based on lower heating values), providing that the maximum capacity of district heat is delivered. The combined production of ethanol, biogas, heat and power has the highest energy efficiency (49%) if district heat is not produced. Neither the inclusion of steam pretreatment nor co-production with ethanol has a large impact on the MBSP. Ethanol is more expensive to produce than biogas is, but this is compensated for by its higher market price. None of the scenarios examined are economically viable, since the MBSP (EUR 103–128 per MWh) is higher than the market price of biogas (EUR 67 per MWh). The largest contribution to the cost is the cost of feedstock. Decreasing the retention time in the biogas process for low solids streams by partly replacing continuous stirred tank reactors by high-rate bioreactors decreases the MBSP. Also, recycling part of the liquid from the effluent from anaerobic digestion decreases the MBSP. The production and prices of methane and ethanol influence the process economics more than the production and prices of electricity and district heat. Conclusions To reduce the production cost of ethanol and biogas from biomass, the use of feedstocks that are cheaper than hemp, give higher output of ethanol and biogas, or combined production with

  7. Assessment of heat tolerance and production performance of Aardi, Damascus, and their crossbred goats.

    PubMed

    Samara, Emad Mohammed; Abdoun, Khalid Ahmed; Okab, Aly Bassunny; Al-Badwi, Mohammed Abdo; El-Zarei, Mohamed Fawzy; Al-Seaf, Ali Mohamed; Al-Haidary, Ahmed Abrahim

    2016-09-01

    The question of whether the adaptability and production performance in goats may be enhanced using a crossbreeding program between bucks of a native and heat-tolerant breed and does of an exotic and dual-purpose breed was approached and examined herein by comparing purebred Aardi and Damascus goats and their crossbred lines (i.e., (1)/2 Aardi (1)/2 Damascus (½A½D) and (1)/4 Aardi (3)/4 Damascus (¼A¾D)) reared in a region characterized by dry and hot bioclimatic conditions. Twenty-four male 6-month-old kids randomly segregated into four groups (six replicates/group) were used for the experiment. Climatic, thermo-physiological, biophysiological, metabolic, blood hematological, and biochemical measurements were all determined. The obtained results indicated that such a program was proven to be successful. This conclusion was demonstrated by the findings that crossbred goats (i.e., (1)/2A(1)/2D and (1)/4A(3)/4D) under such bioclimatic conditions were able to show (P < 0.05) higher heat tolerance capabilities compared to purebred Damascus goats as well as manifested (P < 0.05) higher production performance compared to the purebred Aardi goats. Accordingly, these evidences could emphasize that the crossbreeding may enable these animals to display a simultaneous improvement of both traits by the possible benefits that could arise from heterosis and breed complementarity. Researches dealing with this aspect may very well improve our understanding of goat's production and welfare under harsh environmental conditions. Future studies should include an economic analysis of traits that have the potential to impact the overall profitability to a vertically coordinated system.

  8. Assessment of heat tolerance and production performance of Aardi, Damascus, and their crossbred goats

    NASA Astrophysics Data System (ADS)

    Samara, Emad Mohammed; Abdoun, Khalid Ahmed; Okab, Aly Bassunny; Al-Badwi, Mohammed Abdo; El-Zarei, Mohamed Fawzy; Al-Seaf, Ali Mohamed; Al-Haidary, Ahmed Abrahim

    2016-09-01

    The question of whether the adaptability and production performance in goats may be enhanced using a crossbreeding program between bucks of a native and heat-tolerant breed and does of an exotic and dual-purpose breed was approached and examined herein by comparing purebred Aardi and Damascus goats and their crossbred lines (i.e., 1/2 Aardi 1/2 Damascus (½A½D) and 1/4 Aardi 3/4 Damascus (¼A¾D)) reared in a region characterized by dry and hot bioclimatic conditions. Twenty-four male 6-month-old kids randomly segregated into four groups (six replicates/group) were used for the experiment. Climatic, thermo-physiological, biophysiological, metabolic, blood hematological, and biochemical measurements were all determined. The obtained results indicated that such a program was proven to be successful. This conclusion was demonstrated by the findings that crossbred goats (i.e., 1/2A1/2D and 1/4A3/4D) under such bioclimatic conditions were able to show ( P < 0.05) higher heat tolerance capabilities compared to purebred Damascus goats as well as manifested ( P < 0.05) higher production performance compared to the purebred Aardi goats. Accordingly, these evidences could emphasize that the crossbreeding may enable these animals to display a simultaneous improvement of both traits by the possible benefits that could arise from heterosis and breed complementarity. Researches dealing with this aspect may very well improve our understanding of goat's production and welfare under harsh environmental conditions. Future studies should include an economic analysis of traits that have the potential to impact the overall profitability to a vertically coordinated system.

  9. Assessment of heat tolerance and production performance of Aardi, Damascus, and their crossbred goats

    NASA Astrophysics Data System (ADS)

    Samara, Emad Mohammed; Abdoun, Khalid Ahmed; Okab, Aly Bassunny; Al-Badwi, Mohammed Abdo; El-Zarei, Mohamed Fawzy; Al-Seaf, Ali Mohamed; Al-Haidary, Ahmed Abrahim

    2016-01-01

    The question of whether the adaptability and production performance in goats may be enhanced using a crossbreeding program between bucks of a native and heat-tolerant breed and does of an exotic and dual-purpose breed was approached and examined herein by comparing purebred Aardi and Damascus goats and their crossbred lines (i.e., 1/2 Aardi 1/2 Damascus (½A½D) and 1/4 Aardi 3/4 Damascus (¼A¾D)) reared in a region characterized by dry and hot bioclimatic conditions. Twenty-four male 6-month-old kids randomly segregated into four groups (six replicates/group) were used for the experiment. Climatic, thermo-physiological, biophysiological, metabolic, blood hematological, and biochemical measurements were all determined. The obtained results indicated that such a program was proven to be successful. This conclusion was demonstrated by the findings that crossbred goats (i.e., 1/2A1/2D and 1/4A3/4D) under such bioclimatic conditions were able to show (P < 0.05) higher heat tolerance capabilities compared to purebred Damascus goats as well as manifested (P < 0.05) higher production performance compared to the purebred Aardi goats. Accordingly, these evidences could emphasize that the crossbreeding may enable these animals to display a simultaneous improvement of both traits by the possible benefits that could arise from heterosis and breed complementarity. Researches dealing with this aspect may very well improve our understanding of goat's production and welfare under harsh environmental conditions. Future studies should include an economic analysis of traits that have the potential to impact the overall profitability to a vertically coordinated system.

  10. Augmentation of protein-derived acetic acid production by heat-alkaline-induced changes in protein structure and conformation.

    PubMed

    Wang, Xu; Li, Yanbo; Liu, Junxin; Ren, Nan-Qi; Qu, Jiuhui

    2016-01-01

    Waste-derived acetic acid (HAc) is an attractive feedstock for microbe-mediated biofuel production. However, fermentative conversion of HAc from waste-activated sludge (WAS) has low yield because of the high concentration of proteins not readily utilizable by microorganisms without prior hydrolysis. We investigated a combined technology for HAc augmentation during sludge protein fermentation. The maximal HAc yield increased over two-fold, reaching 0.502 ± 0.021 g/g protein (0.36 ± 0.01 g COD/g COD, ∼52% of the total volatile fatty acids) when synthetic sludge protein was heated at 120 °C for 30 min, treated at pH 12 for 24 h, and fermented at pH 9 for 72 h. Comprehensive analysis illustrated that the heat-alkaline pretreatment significantly induced protein fragmentation, simultaneously increasing the efficiency of protein biohydrolysis (from 35.5% to 85.9%) by inducing conformational changes indicative of protein unfolding. Consequently, the native α-helix content was decreased from 67.3% to 32.5% by conversion to an unordered shape, whose content increased from 27.5% to 45.5%; disulfide bonds were cleaved, whereas the main S-S stretching pattern was altered from gauche-gauche-gauche to gauche-gauche-trans, consequently causing increased protein susceptibility to proteolytic hydrolysis (76.3% vs. 47.0%). Economic analysis indicated that anaerobic fermentation with appropriate heat-alkaline pretreatment is a cost-effective approach for waste conversion to energy sources such as HAc.

  11. RBSE: Product development team research activity deliverables

    NASA Technical Reports Server (NTRS)

    1992-01-01

    The GHG Functions and Extensions to be added to the NASA Electronic Library System (NELS) 1.1 product are described. These functions will implement the 'output request' capability within the Object Browser. The functions will be implemented in two parts. The first part is a code to be added to the Object Browser (X version) to implement menus allowing the user to request that objects be copied to specific media, or that objects be downloaded to the user's system following a specific protocol, or that the object be printed to one of the printers attached to the host system. The second part is shell scripts which support the various menu selections. Additional scripts to support functions within the GHG shell (X version) will also be created along with the X version of the GHG Shell as initial capability for the 27 Mar. prototype. The scripts will be composed of C shell routines that will accept parameters (primary file pathways). Certain limitations in functionality will invoke Mail instead of Oracle Mail since that has yet to be delivered and the NELS invocation will default to the X-Windows version instead of the ASCII version.

  12. Vertical Profiles of Latent Heat Release Over the Global Tropics using TRMM Rainfall Products from December 1997 to November 2001

    NASA Technical Reports Server (NTRS)

    Tao, W.-K.; Lang, S.; Simpson, J.; Meneghini, R.; Halverson, J.; Johnson, R.; Adler, R.; Starr, David (Technical Monitor)

    2002-01-01

    NASA Tropical Rainfall Measuring Mission (TRMM) precipitation radar (PR) derived rainfall information will be used to estimate the four-dimensional structure of global monthly latent heating and rainfall profiles over the global tropics from December 1997 to November 2000. Rainfall, latent heating and radar reflectivity structures between El Nino (DJF 1997-98) and La Nina (DJF 1998-99) will be examined and compared. The seasonal variation of heating over various geographic locations (i.e., oceanic vs continental, Indian ocean vs west Pacific, Africa vs S. America) will also be analyzed. In addition, the relationship between rainfall, latent heating (maximum heating level), radar reflectivity and SST is examined and will be presented in the meeting. The impact of random error and bias in stratiform percentage estimates from PR on latent heating profiles is studied and will also be presented in the meeting. The Goddard Cumulus Ensemble Model is being used to simulate various mesoscale convective systems that developed in different geographic locations. Specifically, the model estimated rainfall, radar reflectivity and latent heating profiles will be compared to observational data collected from TRMM field campaigns over the South China Sea in 1998 (SCSMEX), Brazil in 1999 (TRMM-LBA), and the central Pacific in 1999 (KWAJEX). Sounding diagnosed heating budgets and radar reflectivity from these experiments can provide the means to validate (heating product) as well as improve the GCE model.

  13. Vertical Profiles of Latent Heat Release over the Global Tropics Using TRMM Rainfall Products from December 1997 to November 2002

    NASA Technical Reports Server (NTRS)

    Tao, W.-K.

    2003-01-01

    NASA Tropical Rainfall Measuring Mission (TRMM) precipitation radar (PR) derived rainfall information will be used to estimate the four-dimensional structure of global monthly latent heating and rainfall profiles over the global tropics from December 1997 to November 2000. Rainfall, latent heating and radar reflectivity structures between El Nino (DJF 1997-98) and La Nina (DJF 1998-99) will be examined and compared. The seasonal variation of heating over various geographic locations (i.e., oceanic vs continental, Indian ocean vs west Pacific, Africa vs S. America) will also be analyzed. In addition, the relationship between rainfall, latent heating (maximum heating level), radar reflectivity and SST is examined and will be presented in the meeting. The impact of random error and bias in straitform percentage estimates from PR on latent heating profiles is studied and will also be presented in the meeting. The Goddard Cumulus Ensemble Model is being used to simulate various mesoscale convective systems that developed in different geographic locations. Specifically, the model estimated rainfall, radar reflectivity and latent heating profiles will be compared to observational data collected from TRMM field campaigns over the South China Sea in 1998 (SCSMXX), Brazil in 1999 (TRMM- LBA), and the central Pacific in 1999 (KWAJEX). Sounding diagnosed heating budgets and radar reflectivity from these experiments can provide the means to validate (heating product) as well as improve the GCE model.

  14. Vertical Profiles of Latent Heat Release over the Global Tropics using TRMM rainfall products from December 1997 to November 2001

    NASA Technical Reports Server (NTRS)

    Tao, W.-K.; Lang, S.; Simpson, J.; Meneghini, R.; Halverson, J.; Johnson, R.; Adler, R.

    2002-01-01

    NASA Tropical Rainfall Measuring Mission (TRMM) precipitation radar (PR) derived rainfall information will be used to estimate the four-dimensional structure of global monthly latent heating and rainfall profiles over the global tropics from December 1997 to November 2001. Rainfall, latent heating and radar reflectivity structures between El Nino (DE 1997-98) and La Nina (DJF 1998-99) will be examined and compared. The seasonal variation of heating over various geographic locations (i.e., oceanic vs continental, Indian ocean vs. west Pacific, Africa vs. S. America) will also be analyzed. In addition, the relationship between rainfall, latent heating (maximum heating level), radar reflectivity and SST is examined and will be presented in the meeting. The impact of random error and bias in strtaiform percentage estimates from PR on latent heating profiles is studied and will also be presented in the meeting. The Goddard Cumulus Ensemble Model is being used to simulate various mesoscale convective systems that developed in different geographic locations. Specifically, the model estimated rainfall, radar reflectivity and latent heating profiles will be compared to observational data collected from TRMM field campaigns over the South China Sea in 1998 (SCSMEX), Brazil in 1999 (TRMM-LBA), and the central Pacific in 1999 (KWAJEX). Sounding diagnosed heating budgets and radar reflectivity from these experiments can provide the means to validate (heating product) as well as improve the GCE model.

  15. Antibacterial and Antidiarrheal Activities of Plant Products against Enterotoxinogenic Escherichia coli

    PubMed Central

    Dubreuil, J. Daniel

    2013-01-01

    Enterotoxigenic Escherichia coli (ETEC) produces two types of enterotoxins: heat-labile (LT) and heat-stable (STa and STb). These molecules are involved in the induction of secretory diarrhea in animals including humans. This condition is currently treated using a fluid replacement therapy and antibiotics. This treatment is often not available to people in developing countries, and several die from the condition provoke by ETEC. Over the years, plants and plant extracts have been use as traditional medicine to treat various gastrointestinal ailments including diarrhea. Many of these plant products have been claimed to be active against diarrhea, however few have been extensively studied. The main objective of this review was to gather the scattered information on the antidiarrheal activities reported for various plant products on ETEC. This includes two major effects: (1) The inhibitory effect on bacterial growth or viability and (2) The interference with ETEC enterotoxins activity upon the intestinal epithelium. We will focus on plant products and extracts for which we have major indications of their biological activity against ETEC and their enterotoxins. Because Vibrio cholerae toxin (CT) is structurally, antigenically and mechanistically related to LT, it will also be discussed in this review. PMID:24212181

  16. Zinc might prevent heat-induced hepatic injury by activating the Nrf2-antioxidant in mice.

    PubMed

    Wang, F; Li, Y; Cao, Y; Li, C

    2015-05-01

    Zinc (Zn) is generally known to be an essential trace element with growth-promoting and antioxidant activities. The present study was performed to clarify the role of Zn in the livers of heat-treated mice. Eight-week-old male mice were divided into control (Con), heat treatment (HT) and heat treatment plus zinc groups (HT + Zn) and were fed diets containing 60, 60, or 300 mg/kg Zn (zinc sulfate), respectively. After 30 days of feeding on their respective diets, the control group was maintained at a controlled temperature (25 °C), whereas the HT and HT + Zn groups were exposed to an elevated ambient temperature (40-42 °C) for 2 h each day. After heat exposure for seven consecutive days, sera and liver tissues were collected. The mice in the HT group exhibited reduced liver weights and lower hepatosomatic indices. Histological findings revealed that the hepatocytes of the HT group were subjected to serious damage and exhibited irregular arrangements and nuclear pyknosis. Moreover, in the HT group, the hepatic malondialdehyde levels were significantly increased, while the serum alkaline phosphatase levels, hepatic copper/zinc-superoxide dismutase (CuZn-SOD) and glutathione peroxidase activities were significantly reduced compared to those of the control group. However, in the HT + Zn group, the histomorphology of the liver was restored, the serum aspartate aminotransferase (AST) level was significantly decreased, and the hepatic CuZn-SOD activity was significantly increased compared to the HT group. Furthermore, expressions of the hepatic Nrf2 protein and Nrf2, Keap1, and NQO1 genes in the HT + Zn group were not only higher than the HT group but also higher than the control group. Zn might alleviate heat-induced hepatic injury as revealed by restored histomorphology and AST level. Our results further suggest that Zn might exert its protective effects via the activation of the Nrf2-antioxidant pathway.

  17. Zinc might prevent heat-induced hepatic injury by activating the Nrf2-antioxidant in mice.

    PubMed

    Wang, F; Li, Y; Cao, Y; Li, C

    2015-05-01

    Zinc (Zn) is generally known to be an essential trace element with growth-promoting and antioxidant activities. The present study was performed to clarify the role of Zn in the livers of heat-treated mice. Eight-week-old male mice were divided into control (Con), heat treatment (HT) and heat treatment plus zinc groups (HT + Zn) and were fed diets containing 60, 60, or 300 mg/kg Zn (zinc sulfate), respectively. After 30 days of feeding on their respective diets, the control group was maintained at a controlled temperature (25 °C), whereas the HT and HT + Zn groups were exposed to an elevated ambient temperature (40-42 °C) for 2 h each day. After heat exposure for seven consecutive days, sera and liver tissues were collected. The mice in the HT group exhibited reduced liver weights and lower hepatosomatic indices. Histological findings revealed that the hepatocytes of the HT group were subjected to serious damage and exhibited irregular arrangements and nuclear pyknosis. Moreover, in the HT group, the hepatic malondialdehyde levels were significantly increased, while the serum alkaline phosphatase levels, hepatic copper/zinc-superoxide dismutase (CuZn-SOD) and glutathione peroxidase activities were significantly reduced compared to those of the control group. However, in the HT + Zn group, the histomorphology of the liver was restored, the serum aspartate aminotransferase (AST) level was significantly decreased, and the hepatic CuZn-SOD activity was significantly increased compared to the HT group. Furthermore, expressions of the hepatic Nrf2 protein and Nrf2, Keap1, and NQO1 genes in the HT + Zn group were not only higher than the HT group but also higher than the control group. Zn might alleviate heat-induced hepatic injury as revealed by restored histomorphology and AST level. Our results further suggest that Zn might exert its protective effects via the activation of the Nrf2-antioxidant pathway. PMID:25586622

  18. The effect of standard heat and filtration processing procedures on antimicrobial activity and hydrogen peroxide levels in honey

    PubMed Central

    Chen, Cuilan; Campbell, Leona T.; Blair, Shona E.; Carter, Dee A.

    2012-01-01

    There is increasing interest in the antimicrobial properties of honey. In most honey types, antimicrobial activity is due to the generation of hydrogen peroxide (H2O2), but this can vary greatly among samples. Honey is a complex product and other components may modulate activity, which can be further affected by commercial processing procedures. In this study we examined honey derived from three native Australian floral sources that had previously been associated with H2O2-dependent activity. Antibacterial activity was seen in four red stringybark samples only, and ranged from 12 to 21.1% phenol equivalence against Staphylococcus aureus. Antifungal activity ranged from MIC values of 19–38.3% (w/v) against Candida albicans, and all samples were significantly more active than an osmotically equivalent sugar solution. All honey samples were provided unprocessed and following commercial processing. Processing was usually detrimental to antimicrobial activity, but occasionally the reverse was seen and activity increased. H2O2 levels varied from 0 to 1017 μM, and although samples with no H2O2 had little or no antimicrobial activity, some samples had relatively high H2O2 levels yet no antimicrobial activity. In samples where H2O2 was detected, the correlation with antibacterial activity was greater in the processed than in the unprocessed samples, suggesting other factors present in the honey influence this activity and are sensitive to heat treatment. Antifungal activity did not correlate with the level of H2O2 in honey samples, and overall it appeared that H2O2 alone was not sufficient to inhibit C. albicans. We conclude that floral source and H2O2 levels are not reliable predictors of the antimicrobial activity of honey, which currently can only be assessed by standardized antimicrobial testing. Heat processing should be reduced where possible, and honey destined for medicinal use should be retested post-processing to ensure that activity levels have not changed

  19. Heat shock inhibits lipopolysaccharide-induced tissue factor activity in human whole blood

    PubMed Central

    Sucker, Christoph; Zacharowski, Kai; Thielmann, Matthias; Hartmann, Matthias

    2007-01-01

    Background During gram-negative sepsis, lipopolysaccharide (LPS) induces tissue factor expression on monocytes. The resulting disseminated intravascular coagulation leads to tissue ischemia and worsens the prognosis of septic patients. There are indications, that fever reduces the mortality of sepsis, the effect on tissue factor activity on monocytes is unknown. Therefore, we investigated whether heat shock modulates LPS-induced tissue factor activity in human blood. Methods Whole blood samples and leukocyte suspensions, respectively, from healthy probands (n = 12) were incubated with LPS for 2 hours under heat shock conditions (43°C) or control conditions (37°C), respectively. Subsequent to further 3 hours of incubation at 37°C the clotting time, a measure of tissue factor expression, was determined. Cell integrity was verified by trypan blue exclusion test and FACS analysis. Results Incubation of whole blood samples with LPS for 5 hours at normothermia resulted in a significant shortening of clotting time from 357 ± 108 sec to 82 ± 8 sec compared to samples incubated without LPS (n = 12; p < 0.05). This LPS effect was mediated by tissue factor, as inhibition with active site-inhibited factor VIIa (ASIS) abolished the effect of LPS on clotting time. Blockade of protein synthesis using cycloheximide demonstrated that LPS exerted its procoagulatory effect via an induction of tissue factor expression. Upon heat shock treatment, the LPS effect was blunted: clotting times were 312 ± 66 s in absence of LPS and 277 ± 65 s in presence of LPS (n = 8; p > 0.05). Similarly, heat shock treatment of leukocyte suspensions abolished the LPS-induced tissue factor activity. Clotting time was 73 ± 31 s, when cells were treated with LPS (100 ng/mL) under normothermic conditions, and 301 ± 118 s, when treated with LPS (100 ng/mL) and heat shock (n = 8, p < 0.05). Control experiments excluded cell damage as a potential cause of the observed heat shock effect. Conclusion Heat

  20. Radioactive decay products in neutron star merger ejecta: heating efficiency and γ-ray emission

    NASA Astrophysics Data System (ADS)

    Hotokezaka, K.; Wanajo, S.; Tanaka, M.; Bamba, A.; Terada, Y.; Piran, T.

    2016-06-01

    The radioactive decay of the freshly synthesized r-process nuclei ejected in compact binary mergers powers optical/infrared macronovae (kilonovae) that follow these events. The light curves depend critically on the energy partition among the different decay products and it plays an important role in estimates of the amount of ejected r-process elements from a given observed signal. We show that 20-50 per cent of the total radioactive energy is released in γ-rays on time-scales from hours to a month. The number of emitted γ-rays per unit energy interval has roughly a flat spectrum between a few dozen keV and 1 MeV so that most of the energy is carried by ˜1 MeV γ-rays. However, at the peak of macronova emission the optical depth of the γ-rays is ˜0.02 and most of the γ-rays escape. The loss of these γ-rays reduces the heat deposition into the ejecta and hence reduces the expected macronova signals if those are lanthanides dominated. This implies that the ejected mass is larger by a factor of 2-3 than what was previously estimated. Spontaneous fission heats up the ejecta and the heating rate can increase if a sufficient amount of transuranic nuclei are synthesized. Direct measurements of these escaping γ-rays may provide the ultimate proof for the macronova mechanisms and an identification of the r-process nucleosynthesis sites. However, the chances to detect these signals are slim with current X-ray and γ-ray missions. New detectors, more sensitive by at least a factor of 10, are needed for a realistic detection rate.

  1. Heat shock protein 70, heat shock protein 32, and vascular endothelial growth factor production and their effects on lipopolysaccharide-induced apoptosis in porcine aortic endothelial cells

    PubMed Central

    Bernardini, Chiara; Zannoni, Augusta; Turba, Maria Elena; Fantinati, Paolo; Tamanini, Carlo; Bacci, Maria Laura; Forni, Monica

    2005-01-01

    Lipopolysaccharide (LPS) is a highly proactive molecule that causes in vivo a systemic inflammatory response syndrome and activates in vitro the inflammatory pathway in different cellular types, including endothelial cells (EC). Because the proinflammatory status could lead to EC injury and apoptosis, the expression of proinflammatory genes must be finely regulated through the induction of protective genes. This study aimed at determining whether an LPS exposure is effective in inducing apoptosis in primary cultures of porcine aortic endothelial cells and in stimulating heat shock protein (Hsp)70 and Hsp32 production as well as vascular endothelial growth factor (VEGF) secretion. Cells between third and eighth passage were exposed to 10 μg/mL LPS for 1, 7, 15, and 24 hours (time-course experiments) or to 1, 10, and 100 μg/mL LPS for 7 and 15 hours (dose-response experiments). Apoptosis was not affected by 1 μg/mL LPS but significantly increased in a dose-dependent manner with the highest LPS doses. Furthermore, apoptosis rate increased only till 15 hours of LPS exposure. LPS stimulated VEGF secretion in a dose-dependent manner; its effect became significant after 7 hours and reached a plateau after 15 hours. Both Hsp70 and Hsp32 expressions were induced by LPS in a dose-dependent manner after 7 hours. Subsequent studies were addressed to evaluate the protective role of Hsp32, Hsp70, and VEGF. Hemin, an Hsp32 inducer (5, 20, 50 μM), and recombinant VEGF (100 and 200 ng/mL), were added to the culture 2 hours before LPS (10 μg/mL for 24 hours); to induce Hsp70 expression, cells were heat shocked (42°C for 1 hour) 15 hours before LPS (10 μg/mL for 24 hours). Hemin exposure upregulated Hsp32 expression in a dose-dependent manner and protected cells against LPS-induced apoptosis. Heat shock (HS) stimulated Hsp70 expression but failed to reduce LPS-induced apoptosis; VEGF addition did not protect cells against LPS-induced apoptosis at any dose tested. Nevertheless

  2. Development of Active Gas-Gap Heat Switch for Double-Stage Adiabatic Demagnetization Refrigerators

    NASA Astrophysics Data System (ADS)

    Ishisaki, Y.; Henmi, K.; Akamatsu, H.; Enoki, T.; Ohashi, T.; Hoshino, A.; Shinozaki, K.; Matsuo, H.; Okada, N.; Oshima, T.

    2012-06-01

    We designed and fabricated an active gas-gap heat switch (AGGHS), which ON/OFF the heat conduction between the 1st stage (0.05-2 K) and the 2nd stage (1-4 K) of a double-stage adiabatic demagnetization refrigerator (DADR). Our design geometrically separates two components which dominates the ON or OFF performance, and achieved heat conductivity of 6 mW/K (ON) or 4 μW/K (OFF) at 2 K. The ON/OFF is controlled by a heater attached to the charcoal box to adsorb/deadsorb 4He gas inside. We introduced the AGGHS to the DADR and successfully cooled the detector stage down to 60 mK, working properly more than a year.

  3. Evaluation of a large capacity heat pump concept for active cooling of hypersonic aircraft structure

    NASA Technical Reports Server (NTRS)

    Pagel, L. L.; Herring, R. L.

    1978-01-01

    Results of engineering analyses assessing the conceptual feasibility of a large capacity heat pump for enhancing active cooling of hypersonic aircraft structure are presented. A unique heat pump arrangement which permits cooling the structure of a Mach 6 transport to aluminum temperatures without the aid of thermal shielding is described. The selected concept is compatible with the use of conventional refrigerants, with Freon R-11 selected as the preferred refrigerant. Condenser temperatures were limited to levels compatible with the use of conventional refrigerants by incorporating a unique multipass condenser design, which extracts mechanical energy from the hydrogen fuel, prior to each subsequent pass through the condenser. Results show that it is technically feasible to use a large capacity heat pump in lieu of external shielding. Additional analyses are required to optimally apply this concept.

  4. Active compensation of wavefront aberrations by controllable heating of lens with electric film heater matrix.

    PubMed

    Chen, Hua; Hou, Lv; Zhou, Xinglin

    2016-08-20

    We present a new apparatus for active compensation of wavefront aberrations by controllable heating of a lens using a film heater matrix. The annular electric film heater matrix, comprising 24 individual heaters, is attached to the periphery of a lens. Utilizing the linear superposition, and wavefront change proportional to the heating energy properties induced by heating, a controllable wavefront can be defined by solving a linear function. The two properties of wavefront change of a lens have been confirmed through a specially designed experiment. The feasibility of the compensation method is validated by compensating the wavefront of a plate lens. The results show that the wavefront of the lens changes from 12.52 to 2.95 nm rms after compensation. With a more precise electric controlling board, better results could be achieved. PMID:27556982

  5. Heat reduces nitric oxide production required for auxin-mediated gene expression and fate determination in tree tobacco guard cell protoplasts.

    PubMed

    Beard, Robert A; Anderson, David J; Bufford, Jennifer L; Tallman, Gary

    2012-08-01

    Tree tobacco (Nicotiana glauca) is an equatorial perennial with a high basal thermotolerance. Cultured tree tobacco guard cell protoplasts (GCPs) are useful for studying the effects of heat stress on fate-determining hormonal signaling. At lower temperatures (32°C or less), exogenous auxin (1-naphthalene acetic acid) and cytokinin (6-benzylaminopurine) cause GCPs to expand 20- to 30-fold, regenerate cell walls, dedifferentiate, reenter the cell cycle, and divide. At higher temperatures (34°C or greater), GCPs expand only 5- to 6-fold; they do not regenerate walls, dedifferentiate, reenter the cell cycle, or divide. Heat (38°C) suppresses activation of the BA auxin-responsive transgene promoter in tree tobacco GCPs, suggesting that inhibition of cell expansion and cell cycle reentry at high temperatures is due to suppressed auxin signaling. Nitric oxide (NO) has been implicated in auxin signaling in other plant systems. Here, we show that heat inhibits NO accumulation by GCPs and that L-N(G)-monomethyl arginine, an inhibitor of NO production in animals and plants, mimics the effects of heat by limiting cell expansion and preventing cell wall regeneration; inhibiting cell cycle reentry, dedifferentiation, and cell division; and suppressing activation of the BA auxin-responsive promoter. We also show that heat and L-N(G)-monomethyl arginine reduce the mitotic indices of primary root meristems and inhibit lateral root elongation similarly. These data link reduced NO levels to suppressed auxin signaling in heat-stressed cells and seedlings of thermotolerant plants and suggest that even plants that have evolved to withstand sustained high temperatures may still be negatively impacted by heat stress.

  6. Activated platelets release sphingosine 1-phosphate and induce hypersensitivity to noxious heat stimuli in vivo

    PubMed Central

    Weth, Daniela; Benetti, Camilla; Rauch, Caroline; Gstraunthaler, Gerhard; Schmidt, Helmut; Geisslinger, Gerd; Sabbadini, Roger; Proia, Richard L.; Kress, Michaela

    2015-01-01

    At the site of injury activated platelets release various mediators, one of which is sphingosine 1-phosphate (S1P). It was the aim of this study to explore whether activated human platelets had a pronociceptive effect in an in vivo mouse model and whether this effect was based on the release of S1P and subsequent activation of neuronal S1P receptors 1 or 3. Human platelets were prepared in different concentrations (105/μl, 106/μl, 107/μl) and assessed in mice with different genetic backgrounds (WT, S1P1fl/fl, SNS-S1P1−/−, S1P3−/−). Intracutaneous injections of activated human platelets induced a significant, dose-dependent hypersensitivity to noxious thermal stimulation. The degree of heat hypersensitivity correlated with the platelet concentration as well as the platelet S1P content and the amount of S1P released upon platelet activation as measured with LC MS/MS. Despite the significant correlations between S1P and platelet count, no difference in paw withdrawal latency (PWL) was observed in mice with a global null mutation of the S1P3 receptor or a conditional deletion of the S1P1 receptor in nociceptive primary afferents. Furthermore, neutralization of S1P with a selective anti-S1P antibody did not abolish platelet induced heat hypersensitivity. Our results suggest that activated platelets release S1P and induce heat hypersensitivity in vivo. However, the platelet induced heat hypersensitivity was caused by mediators other than S1P. PMID:25954148

  7. Active Distributed Temperature Sensing to Characterise Soil Moisture and Heat Dynamics of a Vegetated Hillslope.

    NASA Astrophysics Data System (ADS)

    Ciocca, F.; Krause, S.; Chalari, A.; Hannah, D. M.; Mondanos, M.

    2015-12-01

    Complex correlated water and heat dynamics characterise the land surface and shallow subsurface, as consequence of the concurrent action of multiple transport processes. Point sensors and/or remote techniques show limitations in providing precise measurements of key indicators of soil heat and water transport such as soil temperature and moisture, at both high spatiotemporal resolution and large areal coverage. Fibre optics Distributed Temperature Sensors (DTS) allow for precise temperature measurement along optical cables of up to several kilometres, sampling at resolutions of up to few centimetres in space and seconds in time. The optical cable is the sensor and can be buried in the soil with minimum disturbance, to construct soil temperature profiles, over large surveying areas. Soil moisture can be obtained from the analysis of both heating and cooling rates measured by the DTS, when copper conductors embedded in the optical cable are electrically heated (technique known as Active DTS). In July 2015, three loops of optical cable of 500m each have been buried in the soil at different depths (0.05m, 0.25m and 0.40m), along an inclined recently vegetated field in the Birmingham area, UK. Active DTS tests have been set with the aim to characterize the soil temperature and moisture regimes of the field at high spatial resolution, in response to both sporadic events such as showers or scheduled irrigation, and diurnal fluctuations induced by atmospheric forcing. Spatiotemporal variations of the aforementioned regimes will be used to trace vertical and horizontal soil heat and water movements. Finally, assumptions on the possibility to correlate soil heat and water dynamics to a specific process such as precipitation, evapotranspiration, soil inclination, will be discussed. This research is part of the Marie Curie Initial Training Network (ITN) INTERFACES project and is realised in the context of the Free Air Carbon Enrichment (FACE) experiment, in collaboration with

  8. Heat and Mass Transfer Measurements for Tray-Fermented Fungal Products

    NASA Astrophysics Data System (ADS)

    Jou, R.-Y.; Lo, C.-T.

    2011-01-01

    In this study, heat and mass transfer in static tray fermentation, which is widely used in solid-state fermentation (SSF) to produce fungal products, such as enzymes or koji, is investigated. Specifically, kinetic models of transport phenomena in the whole-tray chamber are emphasized. The effects of temperature, moisture, and humidity on microbial growth in large-scale static tray fermentation are essential to scale-up SSF and achieve uniform fermentation. In addition, heat and mass transfer of static tray fermentation of Trichoderma fungi with two tray setups—traditional linen coverings and stacks in a temperature-humidity chamber is examined. In both these setups, the following factors of fermentation were measured: air velocity, air temperature, illumination, pH, carbon dioxide (CO2) concentration, and substrate temperature, and the effects of bed height, moisture of substrate, and relative humidity of air are studied. A thin (1 cm) bed at 28 °C and 95 % relative humidity is found to be optimum. Furthermore, mixing was essential for achieving uniform fermentation of Trichoderma fungi. This study has important applications in large-scale static tray fermentation of fungi.

  9. Production of 238PuO2 heat sources for the Cassini mission

    NASA Astrophysics Data System (ADS)

    George, Timothy G.; Foltyn, Elizabeth M.

    1998-01-01

    NASA's Cassini mission to Saturn, scheduled to launch in October, 1997, is perhaps the most ambitious interplanetary explorer ever constructed. Electric power for the spacecraft's science instruments and on-board computers will be provided by three radioisotope thermoelectric generators (RTGs) powered by 216 238PuO2-fueled General-Purpose Heat Source (GPHS) capsules. In addition, critical equipment and instruments on the spacecraft and Huygens probe will be warmed by 128 Light-Weight Radioisotope Heater Units (LWRHUs). Fabrication and assembly of the GPHS capsules and LWRHU heat sources was performed at Los Alamos National Laboratory (LANL) between January 1994 and September 1996. During this production campaign, LANL pressed and sintered 315 GPHS fuel pellets and 181 LWRHU pellets. By October 1996, NMT-9 had delivered a total of 235 GPHS capsules to EG&G Mound Applied Technologies (EG&G MAT) in Miamisburg, Ohio. EG&G MAT conditioned the capsules for use, loaded the capsules into the Cassini RTGs, tested the RTGs, and coordinated transportation to Kennedy Space Center (KSC). LANL also fabricated and assembled a total of 180 LWRHUs. The LWRHUs required for the Cassini spacecraft were shipped to KSC in mid-1997.

  10. Impurity production and plasma performance in ASDEX discharges with ohmic and auxiliary heating

    NASA Astrophysics Data System (ADS)

    Fussmann, G.; ASDEX Team; NI Team; Icrh Team; Hofmann, J.; Janeschitz, G.; Lenoci, M.; Mast, F.; McCormick, K.; Murmann, H.; Poschenrieder, W.; Roth, J.; Setzensack, C.; Staudenmaier, G.; Steuer, K.-H.; Taglauer, E.; Verbeek, H.; Wagner, F.; Becker, G.; Bosch, H. S.; Brocken, H.; Eberhagen, A.; Gehre, O.; Gernhardt, J.; Gierke, G. V.; Clock, E.; Gruber, O.; Haas, G.; Izvozchikov, A.; Karger, F.; Kaufmann, M.; Keilhacker, M.; Klüber, O.; Kornherr, M.; Lackner, K.; Lisitano, G.; Mayer, H. M.; Meisel, D.; Mertens, V.; Müller, E. R.; Neuhauser, J.; Niedermeyer, H.; Noterdaeme, J.-M.; Pietrzyk, Z. A.; Rapp, H.; Riedler, H.; Röhr, H.; Ryter, F.; Schneider, F.; Siller, G.; Smeulders, P.; Söldner, F. X.; Speth, E.; Steinmetz, K.; Tsois, N.; Ugniewski, S.; Vollmer, O.; Wesner, F.; Zasche, D.

    1987-02-01

    A review is given on investigations in the ASDEX Tokamak on impurities in ohmically, NI and ICRH heated plasmas. For ohmic discharges in H 2 and D 2 it is found that iron release from the wall can be explained by sputtering due to neutral charge exchange (CX) atoms. In the case of He, however, significant contributions caused by ion sputtering are inferred. Comparing discharges with C limiters in He and D 2 suggests that in the case of hydrogen chemical processes are involved in C sputtering. By means of wall carbonization the concentrations of metal ions in the plasma could be substantially reduced. This achievement is of particular importance for NI counter-injection and ICRH, where under non-carbonized conditions severe impurity problems occur. We studied impurity confinement in the case of various heating scenarios by means of the laser injection technique. The poorest confinement is found for the L-phase of NI. Metal injection into the high confinement H-phase generally causes temporary suppression of the edge localized modes (ELM's). With respect to ICRH we conclude that enhanced wall erosion — probably due to the production of high energy ions in the boundary — together with a slightly increased impurity confinement is the dominant reason for the increase of the metallic concentrations. Impurity sputtering as an alternative strong erosion process was experimentally ruled out.

  11. Degradation of toluene, ethylbenzene, and xylene using heat and chelated-ferrous iron activated persulfate oxidation

    NASA Astrophysics Data System (ADS)

    Mondal, P.; Sleep, B.

    2014-12-01

    Toluene, ethylbenze, and xylene (TEX) are common contaminants in the subsurface. Activated persulfate has shown promise for degrading a wide variety of organic compounds. However, studies of persulfate application for in situ degradation of TEX and effects on the subsequent bioremediation are limited. In this work, degradation studies of TEX in aqueous media and soil are being conducted using heat activated and chelated-ferrous iron activated persulfate oxidation in batch and flow-through column experiments. In the batch experiments, sodium persulfate is being used at different concentrations to provide an initial persulfate to TEX molar ratios between 10:1 and 100:1. Sodium persulfate solutions are being activated at 20, 37, 60, and 80 oC temperatures for the heat activated oxidation. For the chelated-ferrous iron activated oxidation, ferrous iron and citric acid, both are being used at concentration of 5 mM. In the experiments with soil slurry, a soil to water ratio of 1 to 5 is being used. Flow through water saturated column experiments are being conducted with glass columns (45 cm in length and 4 cm in diameter) uniformly packed with soils, and equilibrated with water containing TEX at the target concentrations. Both the heat activation and chelated-ferrous iron activation of persulfate are being employed in the column experiments. Future experiments are planned to determine the suitability of persulfate oxidation of TEX on the subsequent biodegradation using batch microcosms containing TEX degrading microbial cultures. In these experiments, the microbial biomass will be monitored using total phospholipids, and the microbial community will be determined using quantitative real-time polymerase chain reaction (qPCR) on the extracted DNA. This study is expected to provide suitable operating conditions for in situ chemical oxidation of TEX with activated persulfate followed by bioremediation.

  12. Different assay conditions for detecting the production and release of heat-labile and heat-stable toxins in enterotoxigenic Escherichia coli isolates.

    PubMed

    Rocha, Letícia B; Ozaki, Christiane Y; Horton, Denise S P Q; Menezes, Caroline A; Silva, Anderson; Fernandes, Irene; Magnoli, Fabio C; Vaz, Tania M I; Guth, Beatriz E C; Piazza, Roxane M F

    2013-12-02

    Enterotoxigenic Escherichia coli (ETEC) produce heat-labile (LT) and/or heat-stable enterotoxins (ST). Despite that, the mechanism of action of both toxins are well known, there is great controversy in the literature concerning the in vitro production and release of LT and, for ST, no major concerns have been discussed. Furthermore, the majority of published papers describe the use of only one or a few ETEC isolates to define the production and release of these toxins, which hinders the detection of ETEC by phenotypic approaches. Thus, the present study was undertaken to obtain a better understanding of ST and LT toxin production and release under laboratory conditions. Accordingly, a collection of 90 LT-, ST-, and ST/LT-producing ETEC isolates was used to determine a protocol for toxin production and release aimed at ETEC detection. For this, we used previously raised anti-LT antibodies and the anti-ST monoclonal and polyclonal antibodies described herein. The presence of bile salts and the use of certain antibiotics improved ETEC toxin production/release. Triton X-100, as chemical treatment, proved to be an alternative method for toxin release. Consequently, a common protocol that can increase the production and release of LT and ST toxins could facilitate and enhance the sensitivity of diagnostic tests for ETEC using the raised and described antibodies in the present work.

  13. Heat generates oxidized linoleic acid metabolites that activate TRPV1 and produce pain in rodents.

    PubMed

    Patwardhan, Amol M; Akopian, Armen N; Ruparel, Nikita B; Diogenes, Anibal; Weintraub, Susan T; Uhlson, Charis; Murphy, Robert C; Hargreaves, Kenneth M

    2010-05-01

    The transient receptor potential vanilloid 1 (TRPV1) channel is the principal detector of noxious heat in the peripheral nervous system. TRPV1 is expressed in many nociceptors and is involved in heat-induced hyperalgesia and thermoregulation. The precise mechanism or mechanisms mediating the thermal sensitivity of TRPV1 are unknown. Here, we have shown that the oxidized linoleic acid metabolites 9- and 13-hydroxyoctadecadienoic acid (9- and 13-HODE) are formed in mouse and rat skin biopsies by exposure to noxious heat. 9- and 13-HODE and their metabolites, 9- and 13-oxoODE, activated TRPV1 and therefore constitute a family of endogenous TRPV1 agonists. Moreover, blocking these substances substantially decreased the heat sensitivity of TRPV1 in rats and mice and reduced nociception. Collectively, our results indicate that HODEs contribute to the heat sensitivity of TRPV1 in rodents. Because oxidized linoleic acid metabolites are released during cell injury, these findings suggest a mechanism for integrating the hyperalgesic and proinflammatory roles of TRPV1 and linoleic acid metabolites and may provide the foundation for investigating new classes of analgesic drugs.

  14. Deubiquitinase activity is required for the proteasomal degradation of misfolded cytosolic proteins upon heat-stress

    PubMed Central

    Fang, Nancy N.; Zhu, Mang; Rose, Amalia; Wu, Kuen-Phon; Mayor, Thibault

    2016-01-01

    Elimination of misfolded proteins is crucial for proteostasis and to prevent proteinopathies. Nedd4/Rsp5 emerged as a major E3-ligase involved in multiple quality control pathways that target misfolded plasma membrane proteins, aggregated polypeptides and cytosolic heat-induced misfolded proteins for degradation. It remained unclear how in one case cytosolic heat-induced Rsp5 substrates are destined for proteasomal degradation, whereas other Rsp5 quality control substrates are otherwise directed to lysosomal degradation. Here we find that Ubp2 and Ubp3 deubiquitinases are required for the proteasomal degradation of cytosolic misfolded proteins targeted by Rsp5 after heat-shock (HS). The two deubiquitinases associate more with Rsp5 upon heat-stress to prevent the assembly of K63-linked ubiquitin on Rsp5 heat-induced substrates. This activity was required to promote the K48-mediated proteasomal degradation of Rsp5 HS-induced substrates. Our results indicate that ubiquitin chain editing is key to the cytosolic protein quality control under stress conditions. PMID:27698423

  15. Reduced heat pain thresholds after sad-mood induction are associated with changes in thalamic activity.

    PubMed

    Wagner, Gerd; Koschke, Mandy; Leuf, Tanja; Schlösser, Ralf; Bär, Karl-Jürgen

    2009-03-01

    Negative affective states influence pain processing in healthy subjects in terms of augmented pain experience. Furthermore, our previous studies revealed that patients with major depressive disorder showed increased heat pain thresholds on the skin. Potential neurofunctional correlates of this finding were located within the fronto-thalamic network. The aim of the present study was to investigate the neurofunctional underpinnings of the influence of sad mood upon heat pain processing in healthy subjects. For this purpose, we used a combination of the Velten Mood Induction procedure and a piece of music to induce sad affect. Initially we assessed heat pain threshold after successful induction of sad mood outside the MR scanner in Experiment 1. We found a highly significant reduction in heat pain threshold on the left hand and a trend for the right. In Experiment 2, we applied thermal pain stimuli on the left hand (37, 42, and 45 degrees C) in an MRI scanner. Subjects were scanned twice, one group before and after sad-mood induction and another group before and after neutral-mood induction, respectively. Our main finding was a significant group x mood-induction interaction bilaterally in the ventrolateral nucleus of the thalamus indicating a BOLD signal increase after sad-mood induction and a BOLD signal decrease in the control group. We present evidence that induced sad affect leads to reduced heat pain thresholds in healthy subjects. This is probably due to altered lateral thalamic activity, which is potentially associated with changed attentional processes.

  16. Experimental investigation on the thermal performance of heat storage walls coupled with active solar systems

    NASA Astrophysics Data System (ADS)

    Zhao, Chunyu; You, Shijun; Zhu, Chunying; Yu, Wei

    2016-02-01

    This paper presents an experimental investigation of the performance of a system combining a low-temperature water wall radiant heating system and phase change energy storage technology with an active solar system. This system uses a thermal storage wall that is designed with multilayer thermal storage plates. The heat storage material is expanded graphite that absorbs a mixture of capric acid and lauric acid. An experiment is performed to study the actual effect. The following are studied under winter conditions: (1) the temperature of the radiation wall surface, (2) the melting status of the thermal storage material in the internal plate, (3) the density of the heat flux, and (4) the temperature distribution of the indoor space. The results reveal that the room temperature is controlled between 16 and 20 °C, and the thermal storage wall meets the heating and temperature requirements. The following are also studied under summer conditions: (1) the internal relationship between the indoor temperature distribution and the heat transfer within the regenerative plates during the day and (2) the relationship between the outlet air temperature and inlet air temperature in the thermal storage wall in cooling mode at night. The results indicate that the indoor temperature is approximately 27 °C, which satisfies the summer air-conditioning requirements.

  17. An efficient heat-inducible Bacillus subtilis bacteriophage 105 expression and secretion system for the production of the Streptomyces clavuligerus beta-lactamase inhibitory protein (BLIP).

    PubMed

    Liu, Hong-Bing; Chui, Ka-Shun; Chan, Chi-Leong; Tsang, Chun-Wai; Leung, Yun-Chung

    2004-03-18

    The Streptomyces clavuligerus beta-lactamase inhibitory protein (BLIP) has been shown to be a potent inhibitor of class A beta-lactamases including the Escherichia coli TEM-1 beta-lactamase (Ki = 0.6 nM). A heat-inducible BLIP expression system was constructed based on a derivative of Bacillus subtilis phage phi105. The recombinant BLIP produced by this system was secreted to the culture medium, purified to homogeneity, and fully active. We have shown that the signal peptide of BLIP functions well in B. subtilis to secrete BLIP out of the cells, which facilitates purification. The absence of a His-tag also avoids the activity and structure of BLIP being altered. An unprecedented high yield of recoverable protein in culture supernatant (3.6mg of >95% pure BLIP/l culture) was achieved by a simple purification protocol. We have developed an efficient production process in which the culture time before heat-induction was 3-4h and the culture supernatant could be collected 5h after induction. This total time of 8-9h is considered to be very short compared to that of the native S. clavuligerus culturing (60-70h). We achieved a very efficient BLIP production rate of 0.8-0.9mg/l/h. Heterologous gene expression was tightly controlled and no production of BLIP was observed before heat-induction, suggesting that cell density can be further increased to improve enzyme yield.

  18. Experimental investigation of solid by-product as sensible heat storage material: Characterization and corrosion study

    NASA Astrophysics Data System (ADS)

    Ortega-Fernández, Iñigo; Faik, Abdessamad; Mani, Karthik; Rodriguez-Aseguinolaza, Javier; D'Aguanno, Bruno

    2016-05-01

    The experimental investigation of water cooled electrical arc furnace (EAF) slag used as filler material in the storage tank for sensible heat storage application was demonstrated in this study. The physicochemical and thermal properties of the tested slags were characterized by using X-ray diffraction, scanning electron microcopy, Fourier transform infrared spectroscopy, Raman spectroscopy and laser flash analysis, respectively. In addition, the chemical compatibility between slags and molten nitrate salt (60 wt. % NaNO3 and 40 wt. % KNO3) was investigated at 565 °C for 500 hrs. The obtained results were clearly demonstrated that the slags showed a good corrosion resistance in direct contact with molten salt at elevated temperature. The present study was clearly indicated that a low-cost filler material used in the storage tank can significantly reduce the overall required quantities of the relatively higher cost molten salt and consequently reduce the overall cost of the electricity production.

  19. AC-Conductivity Measure from Heat Production of Free Fermions in Disordered Media

    NASA Astrophysics Data System (ADS)

    Bru, J.-B.; de Siqueira Pedra, W.; Hertling, C.

    2016-05-01

    We extend (Bru et al. in J Math Phys 56:051901-1-51, 2015) in order to study the linear response of free fermions on the lattice within a (independently and identically distributed) random potential to a macroscopic electric field that is time- and space-dependent. We obtain the notion of a macroscopic AC-conductivity measure which only results from the second principle of thermodynamics. The latter corresponds here to the positivity of the heat production for cyclic processes on equilibrium states. Its Fourier transform is a continuous bounded function which is naturally called (macroscopic) conductivity. We additionally derive Green-Kubo relations involving time-correlations of bosonic fields coming from current fluctuations in the system. This is reminiscent of non-commutative central limit theorems.

  20. Effect of heat treatment on the antioxidative and antigenotoxic activity of extracts from persimmon (Diospyros kaki L.) peel.

    PubMed

    Kim, So-Young; Jeong, Seok-Moon; Kim, Sun-Jung; Jeon, Kyung-Im; Park, Eunju; Park, Hae-Ryong; Lee, Seung-Cheol

    2006-04-01

    Heat treatment of persimmon peel (PP) increased the antioxidative activity of the 70% ethanolic extract (EE) and water extract (WE) from PP. EE and WE both prevented H2O2-induced DNA damage to human peripheral lymphocytes. The antioxidative and antigenotoxic activities of the PP extracts were significantly affected by heating.

  1. Total synthesis and biological activity of natural product Urukthapelstatin A.

    PubMed

    Lin, Chun-Chieh; Tantisantisom, Worawan; McAlpine, Shelli R

    2013-07-19

    Herein we report the first total synthesis of the natural product Urkuthaplestatin A (Ustat A) utilizing a convergent synthetic strategy. The characterization and biological activity match those of the previously published natural product. Interestingly, several intermediates, including the linear and serine cyclized precursors, show a 100-fold decrease in cytotoxicity, with IC50's in the low micromolar range. These data indicate that the rigidity and the consecutive aromatic heterocyclic system are responsible for the biological activity. PMID:23819711

  2. Influence of thermal treatment on color, enzyme activities, and antioxidant capacity of innovative pastelike parsley products.

    PubMed

    Kaiser, Andrea; Brinkmann, Maike; Carle, Reinhold; Kammerer, Dietmar R

    2012-03-28

    Conventional spice powders are often characterized by low sensory quality and high microbial loads. Furthermore, genuine enzymes are only inhibited but not entirely inactivated upon drying, so that they may regain their activity upon rehydration of dried foods. To overcome these problems, initial heating was applied in the present study as the first process step for the production of innovative pastelike parsley products. For this purpose, fresh parsley was blanched (80, 90, and 100 °C for 1-10 min) and subsequently comminuted to form a paste. Alternatively, mincing was carried out prior to heat treatment. Regardless of temperature, the color of the latter product did not show any change after heating for 1 min. With progressing exposure time the green color turned to olive hues due to marked pheophytin formation. Inactivation of genuine peroxidase (POD) and polyphenol oxidase (PPO) was achieved at all temperature-time regimes applied. In contrast, the parsley products obtained after immediate water-blanching were characterized by brighter green colors and enhanced pigment retention. With the exception of the variants water-blanched at 80 °C, POD and PPO were completely inactivated at any of the thermal treatments. Furthermore, in water-blanched samples, antioxidant capacities as determined by the TEAC and FRAP assays were even enhanced compared to unheated parsley, whereas a decrease of phenolic contents could not be prevented. Consequently, the innovative process presented in this study allows the production of novel herb and spice products characterized by improved sensory quality as compared to conventional spice products.

  3. HTGR-GT closed-cycle gas turbine. A plant concept with inherent cogeneration, power plus heat production, capability

    NASA Astrophysics Data System (ADS)

    McDonald, C. F.

    1980-04-01

    The high grade sensible heat rejection characteristic of the high temperature gas cooled reactor gas turbine plant is suited to cogeneration. Cogeneration broadly covers combined power and heat operation modes. Cogeneration in this nuclear closed cycle plant includes: (1) bottoming Rankine cycle, (2) hot water or process steam production, (3) desalination, and (4) urban and industrial district heating. The HTGR-CT plant thermodynamic cycles, design features, and potential applications for the cogeneration operation modes are discussed. The HTGR-CT plant, which potentially approaches 50 percent overall efficiency in a combined cycle mode, can significantly aid national energy goals, particularly resource conservation.

  4. Heat of Combustion of the Product Formed by the Reaction of Diborane with 1,3-Butadiene

    NASA Technical Reports Server (NTRS)

    Tannenbaum, Stanley; Allen, Harrison, Jr.

    1953-01-01

    The net heat of combustion of the product formed by the reaction of diborane with 1,3-butadiene was found to be 18,700+/-150 Btu per pound for the reaction of liquid fuel to gaseous carbon dioxide, gaseous water, and solid boric oxide. The measurements were made in a Parr oxygen-bomb calorimeter, and the combustion was believed to be 98 percent complete. The estimated net heat of combustion for complete combustion would therefore be 19,075+/-150 Btu per pound. Since this value is approximately the same as the heat of combustion of butadiene, it seems certain that the material is partially oxidized.

  5. Exposure of Campylobacter jejuni to 6 degrees C: effects on heat resistance and electron transport activity.

    PubMed

    Hughes, Rebecca-Ayme; Cogan, Tristan; Humphrey, Tom

    2010-04-01

    Human infection with Campylobacter jejuni is frequently associated with the consumption of foods, especially chicken meat, which have been exposed to a range of temperatures during processing, storage, and cooking. Despite the public health importance of C. jejuni, little is known about the effects of cold exposure (refrigeration) on the subsequent ability of this pathogen to survive heat challenge. This work examined the effect of rapid exposure to 6 degrees C for 24 h on the heat resistance at 52 degrees C of 19 C. jejuni strains originally isolated from various sources. The resulting death curves were analyzed with the Weibull model. Unlike cold-exposed cells of Escherichia coli and Salmonella, which have been reported to show significant increased sensitivity to heat, such exposure had only a marginal effect on heat resistance of the C. jejuni strains in this study. A possible explanation for this effect is that rapid chilling renders C. jejuni cells unable to adapt to reduced temperatures in an active manner. This hypothesis is supported by the observation that exposure to 6 degrees C for 24 h resulted in a significant and marked reduction in electron transport system activity when compared with controls at 37 degrees C.

  6. An active role of extratropical sea surface temperature anomalies in determining anomalous turbulent heat flux

    NASA Astrophysics Data System (ADS)

    Tanimoto, Youichi; Nakamura, Hisashi; Kagimoto, Takashi; Yamane, Shozo

    2003-10-01

    Temporal and spatial structures of turbulent latent and sensible heat flux anomalies are examined in relation to dominant patterns of sea surface temperature anomalies (SSTA) observed over the North Pacific. Relative importance among observed anomalies in SST, surface air temperature, and wind speed in determining the anomalous turbulent heat fluxes is assessed through linearizing the observed flux anomalies. Over the central basin of the North Pacific, changes in the atmospheric variables, including air temperature and wind speed, are primarily responsible for the generation of local SST variations by changing turbulent heat flux, which supports a conventional view of extratropical air-sea interaction. In the region where ocean dynamics is very important in forming SSTAs, in contrast, SSTAs that have been formed in early winter play the primary role in determining mid- and late-winter turbulent heat flux anomalies, indicative of the SST forcing upon the overlying atmosphere. Specifically, both decadal scale SSTAs in the western Pacific subarctic frontal zone and El Niño related SSTAs south of Japan are found to be engaged actively in such forcing on the atmosphere. The atmospheric response to this forcing appears to include the anomalous storm track activity. The observed atmospheric anomalies, which may be, in part, forced by the preexisting SSTAs in those two regions, act to force SSTAs in other portions of the basin, leading to the time evolution of SSTAs as observed in the course of the winter season.

  7. Magnetic Characteristics of Active Region Heating Observed with TRACE, SOHO/EIT, and Yohkoh/SXT

    NASA Technical Reports Server (NTRS)

    Porter, J. G.; Falconer, D. A.; Moore, R. L.; Rose, M. Franklin (Technical Monitor)

    2001-01-01

    Over the past several years, we have reported results from studies that have compared the magnetic structure and heating of the transition region and corona (both in active regions and in the quiet Sun) by combining X-ray and EUV images from Yohkoh and Solar and Heliospheric Observatory (SOHO) with photospheric magnetograms from ground-based observatories. Our findings have led us to the hypothesis that most heating throughout the corona is driven from near and below the base of the corona by eruptive microflares occurring in compact low-lying "core magnetic fields (i.e., fields rooted along and closely enveloping polarity inversion lines in the photospheric magnetic flux). We now extend these studies, comparing sequences of UV images from Transition Region and Coronal Explorer (TRACE) with longitudinal magnetograms from Kitt Peak and vector magnetograms from MUSIC. These comparisons confirm the previous results regarding the importance of core-field activity to active region heating. Activity in fields associated with satellite polarity inclusions and/or magnetically sheared configurations is especially prominent. This work is funded by NASA's Office of Space Science through the Sun-Earth Connection Guest Investigator Program and the Solar Physics Supporting Research and Technology Program.

  8. Heat Shock Factor 1 Is a Substrate for p38 Mitogen-Activated Protein Kinases

    PubMed Central

    Dayalan Naidu, Sharadha; Sutherland, Calum; Zhang, Ying; Risco, Ana; de la Vega, Laureano; Caunt, Christopher J.; Hastie, C. James; Lamont, Douglas J.; Torrente, Laura; Chowdhry, Sudhir; Benjamin, Ivor J.; Keyse, Stephen M.; Cuenda, Ana

    2016-01-01

    Heat shock factor 1 (HSF1) monitors the structural integrity of the proteome. Phosphorylation at S326 is a hallmark for HSF1 activation, but the identity of the kinase(s) phosphorylating this site has remained elusive. We show here that the dietary agent phenethyl isothiocyanate (PEITC) inhibits heat shock protein 90 (Hsp90), the main negative regulator of HSF1; activates p38 mitogen-activated protein kinase (MAPK); and increases S326 phosphorylation, trimerization, and nuclear translocation of HSF1, and the transcription of a luciferase reporter, as well as the endogenous prototypic HSF1 target Hsp70. In vitro, all members of the p38 MAPK family rapidly and stoichiometrically catalyze the S326 phosphorylation. The use of stable knockdown cell lines and inhibitors indicated that among the p38 MAPKs, p38γ is the principal isoform responsible for the phosphorylation of HSF1 at S326 in cells. A protease-mass spectrometry approach confirmed S326 phosphorylation and unexpectedly revealed that p38 MAPK also catalyzes the phosphorylation of HSF1 at S303/307, previously known repressive posttranslational modifications. Thus, we have identified p38 MAPKs as highly efficient catalysts for the phosphorylation of HSF1. Furthermore, our findings suggest that the magnitude and persistence of activation of p38 MAPK are important determinants of the extent and duration of the heat shock response. PMID:27354066

  9. Stereospecificity in hydroxyl radical scavenging activities of four ginsenosides produced by heat processing.

    PubMed

    Kang, Ki Sung; Kim, Hyun Young; Yamabe, Noriko; Yokozawa, Takako

    2006-10-01

    The activity-guided fractionation of sun ginseng (SG, heat processed Panax ginseng C. A. Meyer at 120 degrees C) was carried out to identify its main active hydroxyl radical (*OH) scavenging components. As a result, the n-BuOH fraction mainly consisting of ginsenosides showed the strongest activity. Of several ginsenosides of SG, the *OH scavenging activities of relatively high contents of 20(S)-Rg(3), 20(R)-Rg(3), Rk(1), and Rg(5) were compared. Rg(5) and 20(S)-Rg(3) showed strong *OH scavenging IC(50) values of 0.15 and 0.44 mM, respectively, and these activities were prominently higher than each of their respective isomers. Therefore, stereospecificity exists in the *OH scavenging activities of ginsenosides produced by heat processing. Especially, the double bond at carbon-20(22) or the OH group at carbon-20 geometrically close to OH at carbon-12 is thought to increase the *OH scavenging activity of ginsenosides.

  10. Combustion instability and active control: Alternative fuels, augmentors, and modeling heat release

    NASA Astrophysics Data System (ADS)

    Park, Sammy Ace

    Experimental and analytical studies were conducted to explore thermo-acoustic coupling during the onset of combustion instability in various air-breathing combustor configurations. These include a laboratory-scale 200-kW dump combustor and a 100-kW augmentor featuring a v-gutter flame holder. They were used to simulate main combustion chambers and afterburners in aero engines, respectively. The three primary themes of this work includes: 1) modeling heat release fluctuations for stability analysis, 2) conducting active combustion control with alternative fuels, and 3) demonstrating practical active control for augmentor instability suppression. The phenomenon of combustion instabilities remains an unsolved problem in propulsion engines, mainly because of the difficulty in predicting the fluctuating component of heat release without extensive testing. A hybrid model was developed to describe both the temporal and spatial variations in dynamic heat release, using a separation of variables approach that requires only a limited amount of experimental data. The use of sinusoidal basis functions further reduced the amount of data required. When the mean heat release behavior is known, the only experimental data needed for detailed stability analysis is one instantaneous picture of heat release at the peak pressure phase. This model was successfully tested in the dump combustor experiments, reproducing the correct sign of the overall Rayleigh index as well as the remarkably accurate spatial distribution pattern of fluctuating heat release. Active combustion control was explored for fuel-flexible combustor operation using twelve different jet fuels including bio-synthetic and Fischer-Tropsch types. Analysis done using an actuated spray combustion model revealed that the combustion response times of these fuels were similar. Combined with experimental spray characterizations, this suggested that controller performance should remain effective with various alternative fuels

  11. Methane production and solids destruction in an anaerobic solid waste reactor due to post-reactor caustic and heat treatment.

    PubMed

    Distefano, T D; Ambulkar, A

    2006-01-01

    This study was undertaken to determine the feasibility of caustic and heat treatment of sludge from a dry anaerobic reactor (DAR) with respect to increased methane production and solids destruction. The DAR was operated semi-continuously at 55 degrees C on sized-reduced municipal solid waste at a solids retention time of 15 days. A respirometer was employed to monitor the extent and rate of methane production from anaerobic biodegradation of DAR sludge that was treated with caustic and heat. Results indicate that caustic and heat treatment at 50 degrees C and 175 degrees C increased methane production by 22% and 52%, respectively. Also, volatile solids destruction increased from 46% to 58% and 83%, respectively. Based on these results, economic analysis for a full-scale 10(5) kg/d facility suggests that annual project revenue for 50 degrees C and 175 degrees C treatment is estimated at $21,000 and $445,000, respectively.

  12. Extracellular heat shock protein 90 binding to TGFβ receptor I participates in TGFβ-mediated collagen production in myocardial fibroblasts.

    PubMed

    García, Raquel; Merino, David; Gómez, Jenny M; Nistal, J Francisco; Hurlé, María A; Cortajarena, Aitziber L; Villar, Ana V

    2016-10-01

    The pathological remodeling heart shows an increase in left ventricular mass and an excess of extracellular matrix deposition that can over time cause heart failure. Transforming growth factor β (TGFβ) is the main cytokine controlling this process. The molecular chaperone heat shock protein 90 (Hsp90) has been shown to play a critical role in TGFβ signaling by stabilizing the TGFβ signaling cascade. We detected extracellular Hsp90 in complex with TGFβ receptor I (TGFβRI) in fibroblasts and determined a close proximity between both proteins suggesting a potential physical interaction between the two at the plasma membrane. This was supported by in silico studies predicting Hsp90 dimers and TGFβRI extracellular domain interaction. Both, Hsp90aa1 and Hsp90ab1 isoforms participate in TGFβRI complex. Extracellular Hsp90 inhibition lessened the yield of collagen production as well as the canonical TGFβ signaling cascade, and collagen protein synthesis was drastically reduced in Hsp90aa1 KO mice. These observations together with the significant increase in activity of Hsp90 at the plasma membrane pointed to a functional cooperative partnership between Hsp90 and TGFβRI in the fibrotic process. We propose that a surface population of Hsp90 extracellularly binds TGFβRI and this complex behaves as an active participant in collagen production in TGFβ-activated fibroblasts. We also offer an in vivo insight into the role of Hsp90 and its isoforms during cardiac remodeling in murine aortic banding model suffering from pathological cardiac remodeling and detect circulating Hsp90 overexpressed in remodeling mice.

  13. Optimization of a heat-tolerant β-glucosidase production by Bacillus sp. ZJ1308 and its purification and characterization.

    PubMed

    Xu, Zhenni; Zhang, Lei; Yu, Ping

    2016-07-01

    Response surface methodology was used to optimize the medium composition to improve the production of the heat-tolerant β-glucosidase from Bacillus sp. ZJ1308. Three significant factors were found to be corn cob, beef extract, and MnSO4 ·H2 O. The final medium compositions optimized were corn cob (51.8 g/L), beef extract (23.8 g/L), salicin (0.5 g/L), MnSO4 ·H2 O (0.363 g/L), MgSO4 ·7H2 O (0.4 g/L), and NaCl (5 g/L). Under the optimal conditions, the activity of β-glucosidase was up to 4.71 U/mL. β-Glucosidase was purified to homogeneity with a recovery rate of 5% and a specific activity of 110.47 U/mg. The optimal pH and temperature were 7.0 and 60 °C, respectively. β-Glucosidase was stable within a pH range of 6.0-8.0 and showed an extremely high thermostability at 80 and 90 °C, retaining 56% and 38% of its maximal activity, respectively. Ni(2+) and Ba(2+) heavily inhibited the β-glucosidase activity. The purified β-glucosidase showed a high substrate specificity. The kinetic parameters revealed that it had a high catalytic efficiency toward the substrate p-nitrophenyl-β-d-glucopyranoside (Kcat /Km = 700). It also showed a high catalytic activity toward the natural substrate salicin. This study provides a new insight into the future development and use of β-glucosidase from Bacillus sp. ZJ1308. PMID:26077129

  14. Which Words Are Activated during Bilingual Word Production?

    ERIC Educational Resources Information Center

    Colome, Angels; Miozzo, Michele

    2010-01-01

    Whether words are or are not activated within the lexicon of the nonused language is an important question for accounts of bilingual word production. Prior studies have not led to conclusive results, either because alternative accounts could be proposed for their findings or because activation could have been artificially induced by the…

  15. [Cytogenetic activity of the butylcaptax defoliant transformation product].

    PubMed

    Vesmanova, O Ia; Semykina, E E; Koblov, R K; Ergashev

    1989-01-01

    Cytogenetical activity of the product of metabolitic butylcaptax transformations in cells of cotton plants G. barbadense has been studied. It is shown that butylcaptax, with a significant mutagenicity, looses its mutagenic activity, metabolizing in low mutagenic 2-oxyamylthiobenzthiazole. Low water solubility prevents its concentration to exceed 0.005% in tissue liquids and to exert a mutagenic action on cotton plants. PMID:2773061

  16. [Cytogenetic activity of the butylcaptax defoliant transformation product].

    PubMed

    Vesmanova, O Ia; Semykina, E E; Koblov, R K; Ergashev

    1989-01-01

    Cytogenetical activity of the product of metabolitic butylcaptax transformations in cells of cotton plants G. barbadense has been studied. It is shown that butylcaptax, with a significant mutagenicity, looses its mutagenic activity, metabolizing in low mutagenic 2-oxyamylthiobenzthiazole. Low water solubility prevents its concentration to exceed 0.005% in tissue liquids and to exert a mutagenic action on cotton plants.

  17. A vascular injury model using focal heat-induced activation of endothelial cells

    PubMed Central

    Sylman, J.L.; Artzer, D.T.; Rana, K.; Neeves, K.B.

    2015-01-01

    Endothelial cells (EC) both inhibit and promote platelet function depending on their activation state. Quiescent EC inhibit platelet activation by constitutive secretion of platelet inhibitors. Activated EC promote platelet adhesion by secretion of von Willebrand factor (vWF). EC also secrete an extracellular matrix that support platelet adhesion when exposed following vascular injury. Previous studies of EC-platelet interactions under flow activate entire monolayers of cells by chemical activation. In this study, EC cultured in microfluidic channels were focally activated by heat from an underlying microelectrode. Based on finite element modeling, microelectrodes induced peak temperature increases of 10–40 °C above 37 °C after applying 5–9 V for 30 s resulting in three zones: (1) A quiescent zone corresponded to peak temperatures of less than 15 °C characterized by no EC activation or platelet accumulation. (2) An activation zone corresponding to an increase of 16–22 °C yielded EC that were viable, secreted elevated levels of vWF, and were P-selectin positive. Platelets accumulated in the retracted spaces between EC in the activation zone at a wall shear rate of 150 s−1. Experiments with blocking antibodies show that platelets adhere via GPIbα-vWF and α6β1-laminin interactions. (3) A kill zone corresponded to peak temperatures of greater than 23 °C where EC were not viable and did not support platelet adhesion. These data define heating conditions for the activation of EC, causing the secretion of vWF and the exposure of a subendothelial matrix that support platelet adhesion and aggregation. This model provides for spatially defined zones of EC activation that could be a useful tool for measuring the relative roles of anti- and prothrombotic roles of EC at the site of vascular injury. PMID:26087748

  18. Assessment of activation products in the Savannah River Site environment

    SciTech Connect

    Carlton, W.H.; Denham, M.

    1996-07-01

    This document assesses the impact of radioactive activation products released from SRS facilities since the first reactor became operational late in 1953. The isotopes reported here are those whose release resulted in the highest dose to people living near SRS: {sup 32}P, {sup 51}Cr, {sup 60}C, and {sup 65}Zn. Release pathways, emission control features, and annual releases to the aqueous and atmospheric environments are discussed. No single incident has resulted in a major acute release of activation products to the environment. The releases were the result of normal operations of the reactors and separations facilities. Releases declined over the years as better controls were established and production was reduced. The overall radiological impact of SRS activation product atmospheric releases from 1954 through 1994 on the offsite maximally exposed individual can be characterized by a total dose of 0.76 mrem. During the same period, such an individual received a total dose of 14,400 mrem from non-SRS sources of ionizing radiation present in the environment. SRS activation product aqueous releases between 1954 and 1994 resulted in a total dose of 54 mrem to the offsite maximally exposed individual. The impact of SRS activation product releases on offsite populations also has been evaluated.

  19. Thermoregulation and heat exchange in a nonuniform thermal environment during simulated extended EVA. Extravehicular activities

    NASA Technical Reports Server (NTRS)

    Koscheyev, V. S.; Leon, G. R.; Hubel, A.; Nelson, E. D.; Tranchida, D.

    2000-01-01

    BACKGROUND: Nonuniform heating and cooling of the body, a possibility during extended duration extravehicular activities (EVA), was studied by means of a specially designed water circulating garment that independently heated or cooled the right and left sides of the body. The purpose was to assess whether there was a generalized reaction on the finger in extreme contradictory temperatures on the body surface, as a potential heat status controller. METHOD: Eight subjects, six men and two women, were studied while wearing a sagittally divided experimental garment with hands exposed in the following conditions: Stage 1 baseline--total body garment inlet water temperature at 33 degrees C; Stage 2--left side inlet water temperature heated to 45 degrees C; right side cooled to 8 degrees C; Stage 3--left side inlet water temperature cooled to 8 degrees C, right side heated to 45 degrees C. RESULTS: Temperatures on each side of the body surface as well as ear canal temperature (Tec) showed statistically significant Stage x Side interactions, demonstrating responsiveness to the thermal manipulations. Right and left finger temperatures (Tfing) were not significantly different across stages; their dynamic across time was similar. Rectal temperature (Tre) was not reactive to prevailing cold on the body surface, and therefore not informative. Subjective perception of heat and cold on the left and right sides of the body was consistent with actual temperature manipulations. CONCLUSIONS: Tec and Tre estimates of internal temperature do not provide accurate data for evaluating overall thermal status in nonuniform thermal conditions on the body surface. The use of Tfing has significant potential in providing more accurate information on thermal status and as a feedback method for more precise thermal regulation of the astronaut within the EVA space suit.

  20. Relating Alfvén Wave Heating Model to Observations of a Solar Active Region

    NASA Astrophysics Data System (ADS)

    Yoritomo, J. Y.; Van Ballegooijen, A. A.

    2012-12-01

    We compared images from the Solar Dynamics Observatory's (SDO) Atmospheric Imaging Assembly (AIA) with simulations of propagating and dissipating Alfvén waves from a three-dimensional magnetohydrodynamic (MHD) model (van Ballegooijen et. al 2011; Asgari-Targhi & van Ballegooijen 2012). The goal was to search for observational evidence of Alfvén waves in the solar corona and understand their role in coronal heating. We looked at one particular active region on the 5th of May 2012. Certain distinct loops in the SDO/AIA observations were selected and expanded. Movies were created from these selections in an attempt to discover transverse motions that may be Alfvén waves. Using a magnetogram of that day and the corresponding synoptic map, a potential field model was created for the active region. Three-dimensional MHD models for several loops in different locations in the active region were created. Each model specifies the temperature, pressure, magnetic field strength, average heating rate, and other parameters along the loop. We find that the heating is intermittent in the loops and reflection occurs at the transition region. For loops at larger and larger height, a point is reached where thermal non-equilibrium occurs. In the center this critical height is much higher than in the periphery of the active region. Lastly, we find that the average heating rate and coronal pressure decrease with increasing height in the corona. This research was supported by an NSF grant for the Smithsonian Astrophysical Observatory (SAO) Solar REU program and a SDO/AIA grant for the Smithsonian Astrophysical Observatory.

  1. A Maillard reaction product enhances eNOS activity in human endothelial cells.

    PubMed

    Schmitt, Christoph A; Heiss, Elke H; Schachner, Daniel; Aristei, Yasmin; Severin, Theodor; Dirsch, Verena M

    2010-07-01

    Nitric oxide (NO) produced by the endothelial nitric oxide synthase (eNOS) is an important signaling molecule in the cardiovascular system. Although dietary factors can modulate eNOS activity, putative effects of processed food are barely investigated. We aimed to examine whether the model Maillard reaction product 3-hydroxy-2-methyl-1-propyl-4(1H)-pyridone (HMPP), formed from maltol or starch and propylamine, affects the eNOS system. Incubation of EA.hy926 endothelial cells with 30-300 microM HMPP for 18 h enhanced endothelial NO release measured with the fluorescent probe diaminofluorescein-2 and eNOS activity determined by the [14C]L-arginine-[14C]L-citrulline conversion assay. HMPP increased NO production also in two different types of primary human endothelial cells. Protein levels of eNOS and inducible NO synthase remained unaltered by HMPP. HMPP inhibited eNOS activity within the first 2-4 h, whereas it potently increased eNOS activity after 12-24 h. Levels of eNOS phosphorylation, expression of heat-shock protein 90, caveolin-1 and various antioxidant enzymes were not affected. Intracellular reactive oxygen species remained unchanged by HMPP. This is the first study to demonstrate positive effects of a Maillard reaction product on eNOS activity and endothelial NO production, which is considered favourable for cardiovascular protection. PMID:20112298

  2. Milk kefir: composition, microbial cultures, biological activities, and related products.

    PubMed

    Prado, Maria R; Blandón, Lina Marcela; Vandenberghe, Luciana P S; Rodrigues, Cristine; Castro, Guillermo R; Thomaz-Soccol, Vanete; Soccol, Carlos R

    2015-01-01

    In recent years, there has been a strong focus on beneficial foods with probiotic microorganisms and functional organic substances. In this context, there is an increasing interest in the commercial use of kefir, since it can be marketed as a natural beverage that has health promoting bacteria. There are numerous commercially available kefir based-products. Kefir may act as a matrix in the effective delivery of probiotic microorganisms in different types of products. Also, the presence of kefir's exopolysaccharides, known as kefiran, which has biological activity, certainly adds value to products. Kefiran can also be used separately in other food products and as a coating film for various food and pharmaceutical products. This article aims to update the information about kefir and its microbiological composition, biological activity of the kefir's microflora and the importance of kefiran as a beneficial health substance.

  3. Milk kefir: composition, microbial cultures, biological activities, and related products

    PubMed Central

    Prado, Maria R.; Blandón, Lina Marcela; Vandenberghe, Luciana P. S.; Rodrigues, Cristine; Castro, Guillermo R.; Thomaz-Soccol, Vanete; Soccol, Carlos R.

    2015-01-01

    In recent years, there has been a strong focus on beneficial foods with probiotic microorganisms and functional organic substances. In this context, there is an increasing interest in the commercial use of kefir, since it can be marketed as a natural beverage that has health promoting bacteria. There are numerous commercially available kefir based-products. Kefir may act as a matrix in the effective delivery of probiotic microorganisms in different types of products. Also, the presence of kefir’s exopolysaccharides, known as kefiran, which has biological activity, certainly adds value to products. Kefiran can also be used separately in other food products and as a coating film for various food and pharmaceutical products. This article aims to update the information about kefir and its microbiological composition, biological activity of the kefir’s microflora and the importance of kefiran as a beneficial health substance. PMID:26579086

  4. Particle size distribution and morphological changes in activated carbon-metal oxide hybrid catalysts prepared under different heating conditions.

    PubMed

    Barroso-Bogeat, A; Alexandre-Franco, M; Fernández-González, C; Gómez-Serrano, V

    2016-03-01

    In catalysis processes, activated carbon (AC) and metal oxides (MOs) are widely used either as catalysts or as catalyst supports because of their unique properties. A combination of AC and a MO in a single hybrid material entails changes not only in the composition, microstructure and texture but also in the morphology, which may largely influence the catalytic behaviour of the resulting product. This work is aimed at investigating the modifications in the morphology and particle size distribution (PSD) for AC-MO hybrid catalysts as a result of their preparation under markedly different heating conditions. From a commercial AC and six MO (Al2O3, Fe2O3, ZnO, SnO2, TiO2 and WO3) precursors, two series of such catalysts are prepared by wet impregnation, oven-drying at 120 ºC, and subsequent heat treatment at 200 ºC or 850 ºC in inert atmosphere. The resulting samples are characterized in terms of their morphology and PSD by scanning electron microscopy and ImageJ processing program. Obtained results indicate that the morphology, PSD and degree of dispersion of the supported catalysts are strongly dependent both on the MO precursor and the heat treatment temperature. With the temperature rise, trends are towards the improvement of crystallinity, the broadening of the PSD and the increase in the average particle size, thus suggesting the involvement of sintering mechanisms. Such effects are more pronounced for the Fe, Sn and W catalysts due to the reduction of the corresponding MOs by AC during the heat treatment at 850 ºC.

  5. Nitric oxide production and tolerance differ among Symbiodinium types exposed to heat stress.

    PubMed

    Hawkins, Thomas D; Davy, Simon K

    2012-11-01

    Nitric oxide (NO) is a ubiquitous molecule and its involvement in metazoan-microbe symbiosis is well known. Evidence suggests that it plays a role in the temperature-induced breakdown ('bleaching') of the ecologically important cnidarian-dinoflagellate association, and this can often lead to widespread mortality of affected hosts. This study confirms that dinoflagellates of the genus Symbiodinium can produce NO and that production of the compound is differentially regulated in different types when exposed to elevated temperature. Temperature-sensitive type B1 cells under heat stress (8°C above ambient) exhibited significant increases in NO synthesis, which occurred alongside pronounced photoinhibition and cell mortality. Tolerant type A1 cells also displayed increases in NO production, yet maintained photosynthetic yields at levels similar to those of untreated cells and displayed less dramatic increases in cell death. Type C1 cells displayed a down-regulation of NO synthesis at high temperature, and no significant mortality increases were observed in this type. Temperature-induced mortality in types A1 and B1 was affected by the prevailing level of NO and, furthermore, photosynthetic yields of these temperature-tolerant and -sensitive types appeared differentially susceptible to NO donated by pharmacological agents. Taken together, these differences in NO synthesis and tolerance could potentially influence the varying bleaching responses seen among hosts harboring different Symbiodinium types.

  6. Detection of horse meat contamination in raw and heat-processed meat products.

    PubMed

    Hsieh, Yun-Hwa P; Ofori, Jack A

    2014-12-31

    Europe's recent problems with the adulteration of beef products with horse meat highlight the need for a reliable method for detecting horse meat in food for human consumption. The objective of this study was therefore to develop a reliable monoclonal antibody (mAb) based enzyme-linked immunosorbent assay (ELISA) for horse meat detection. Two mAbs, H3E3 (IgG2b) and H4E7 (IgG2a), were characterized as horse-selective, and competitive ELISAs (cELISAs) employing these mAbs were developed. The cELISAs were found to be capable of detecting levels as low as 1% of horse meat in raw, cooked, and autoclaved ground beef or pork, being useful analytical tools for addressing the health, economic, and ethical concerns associated with adulterating meat products with horse meat. However, due to cross-reaction with raw poultry meat, it is recommended that samples be heated (100 °C for 15 min) prior to analysis to eliminate possible false-positive results.

  7. Co-composting of eggshell waste in self-heating reactors: monitoring and end product quality.

    PubMed

    Soares, Micaela A R; Quina, Margarida M J; Quinta-Ferreira, Rosa M

    2013-11-01

    Industrial eggshell waste (ES) is classified as an animal by-product not intended to human consumption. For reducing pathogen spreading risk due to soil incorporation of ES, sanitation by composting is a pre-treatment option. This work aims to evaluate eggshell waste recycling in self-heating composting reactors and investigate ES effect on process evolution and end product quality. Potato peel, grass clippings and rice husks were the starting organic materials considered. The incorporation of 30% (w/w) ES in a composting mixture did not affect mixture biodegradability, nor its capacity to reach sanitizing temperatures. After 25 days of composting, ES addition caused a nitrogen loss of about 10 g N kg(-1) of initial volatile solids, thus reducing nitrogen nutritional potential of the finished compost. This study showed that a composting mixture with a significant proportion of ES (30% w/w) may be converted into calcium-rich marketable compost to neutralize soil acidity and/or calcium deficiencies. PMID:24055972

  8. Photodissociation studies of HNCO: heat of formation and product branching ratios

    SciTech Connect

    Spiglanin, T.A.; Perry, R.A.; Chandler, D.W.

    1986-11-06

    The heat of formation (..delta..H/sub f/(298 K)) of HNCO is determined to be -24.9/sub -2.8//sup +0.7/ kcal/mol (based on ..delta..H/sub f/(NH) = 85.2 kcal/mol). This value is obtained by measuring the threshold for the production of NH(a/sup 1/..delta..) and by determining the energy contents of the NH fragment and the CO cofragment produced by photolysis of HNCO at wavelengths near the threshold. Saturated laser-induced fluorescence is used to determine the internal state distribution of NH(a/sup 1/..delta..), and multiphoton ionization is used to measure the internal state distribution of CO. An upper limit for the branching ratio of NCO/NH production from photodissociation of HNCO at 193 nm is determined from an analysis of kinetic experiments to be 0.10. To clarify the mechanism of photodissociation, HNCO fluorescence-excitation and NH(a/sup 1/..delta..) action spectra are also measured. They imply that two excited states of HNCO are present where only one had previously been considered.

  9. Heat of Combustion of the Product Formed by the Reaction of Acetylene and Diborane (LFPL-CZ-3)

    NASA Technical Reports Server (NTRS)

    Allen, Harrison, Jr.; Tannenbaum, Stanley

    1957-01-01

    The heat of combustion of the product formed by the reaction acetylene and diborane was found to be 20,100 +/- 100 Btu per pound for the reaction of liquid fuel to gaseous carbon dioxide, gaseous water, and solid boric oxide. The measurements were made in a Parr oxygen-bomb calorimeter, and chemical analyses both of the sample and of the combustion products indicated combustion in the bomb calorimeter to have been 97 percent complete. The estimated net heat of combustion for complete combustion would therefore be 20,700 +/- 100 Btu per pound.

  10. Impact of heating on passive and active biomechanics of suspended cells

    PubMed Central

    Chan, C. J.; Whyte, G.; Boyde, L.; Salbreux, G.; Guck, J.

    2014-01-01

    A cell is a complex material whose mechanical properties are essential for its normal functions. Heating can have a dramatic effect on these mechanical properties, similar to its impact on the dynamics of artificial polymer networks. We investigated such mechanical changes by the use of a microfluidic optical stretcher, which allowed us to probe cell mechanics when the cells were subjected to different heating conditions at different time scales. We find that HL60/S4 myeloid precursor cells become mechanically more compliant and fluid-like when subjected to either a sudden laser-induced temperature increase or prolonged exposure to higher ambient temperature. Above a critical temperature of 52 ± 1°C, we observed active cell contraction, which was strongly correlated with calcium influx through temperature-sensitive transient receptor potential vanilloid 2 (TRPV2) ion channels, followed by a subsequent expansion in cell volume. The change from passive to active cellular response can be effectively described by a mechanical model incorporating both active stress and viscoelastic components. Our work highlights the role of TRPV2 in regulating the thermomechanical response of cells. It also offers insights into how cortical tension and osmotic pressure govern cell mechanics and regulate cell-shape changes in response to heat and mechanical stress. PMID:24748957

  11. Close-spaced thermionic converters with active spacing control and heat-pipe isothermal emitters

    SciTech Connect

    Fitzpatrick, G.O.; Koester, J.K.; Chang, J.; Britt, E.J.; McVey, J.B.

    1996-12-31

    Thermionic converters with interelectrode gaps smaller than 10 microns are capable of substantial performance improvements over conventional ignited mode diodes. Previous devices which have demonstrated operation at such small gaps have done so at low power densities and emitter temperatures. Higher power operation requires overcoming two primary design issues: thermal distortion of the emitter due to temperature gradients and degradation of the in-gap spacers at higher emitter temperatures. This work describes two innovations for solution of these issues. The issue of thermal distortion was addressed by an isothermal emitter incorporating a heat-pipe into its structure. Such a heat-pipe emitter, with a single-crystal emitting surface, was fabricated and characterized. Finite-element computational modeling was used to analyze its distortion with an applied heat flux. The calculations suggested that thermal distortion would be significantly reduced as compared with a solid emitter. Ongoing work and preliminary experimental results are described for a system of active interelectrode gap control. In the present design an integral transducer determines the interelectrode gap of the converter. Initial designs for spacing actuators and their required cesium vapor seals are discussed. A novel hot-shell converter design incorporating active spacing control and low-temperature seals is presented. A converter incorporating the above features would be capable of near ideal-converter performance at high power densities. In addition, active spacing control can potentially completely eliminate short-circuit failures in thermionic converter systems.

  12. Heat production in depth up to 2500m via in situ combustion of methane using a counter-current heat-exchange reactor

    NASA Astrophysics Data System (ADS)

    Schicks, Judith Maria; Spangenberg, Erik; Giese, Ronny; Heeschen, Katja; Priegnitz, Mike; Luzi-Helbing, Manja; Thaler, Jan; Abendroth, Sven; Klump, Jens

    2014-05-01

    In situ combustion is a well-known method used for exploitation of unconventional oil deposits such as heavy oil/bitumen reservoirs where the required heat is produced directly within the oil reservoir by combustion of a small percentage of the oil. A new application of in situ combustion for the production of methane from hydrate-bearing sediments was tested at pilot plant scale within the first phase of the German national gas hydrate project SUGAR. The applied method of in situ combustion was a flameless, catalytic oxidation of CH4 in a counter-current heat-exchange reactor with no direct contact between the catalytic reaction zone and the reservoir. The catalyst permitted a flameless combustion of CH4 with air to CO2 and H2O below the auto-ignition temperature of CH4 in air (868 K) and outside the flammability limits. This led to a double secured application of the reactor. The relatively low reaction temperature allowed the use of cost-effective standard materials for the reactor and prevented NOx formation. Preliminary results were promising and showed that only 15% of the produced CH4 was needed to be catalytically burned to provide enough heat to dissociate the hydrates in the environment and release CH4. The location of the heat source right within the hydrate-bearing sediment is a major advantage for the gas production from natural gas hydrates as the heat is generated where it is needed without loss of energy due to transportation. As part of the second period of the SUGAR project the reactor prototype of the first project phase was developed further to a borehole tool. The dimensions of this counter-current heat-exchange reactor are about 540 cm in length and 9 cm in diameter. It is designed for applications up to depths of 2500 m. A functionality test and a pressure test of the reactor were successfully carried out in October 2013 at the continental deep drilling site (KTB) in Windischeschenbach, Germany, in 600 m depth and 2000 m depth, respectively

  13. Effects of Heat Shock on Photosynthetic Properties, Antioxidant Enzyme Activity, and Downy Mildew of Cucumber (Cucumis sativus L.)

    PubMed Central

    Hao, Ting; Jin, Haijun; Zhang, Hongmei; He, Lizhong; Zhou, Qiang; Huang, Danfeng; Hui, Dafeng; Yu, Jizhu

    2016-01-01

    Heat shock is considered an abiotic stress for plant growth, but the effects of heat shock on physiological responses of cucumber plant leaves with and without downy mildew disease are still not clear. In this study, cucumber seedlings were exposed to heat shock in greenhouses, and the responses of photosynthetic properties, carbohydrate metabolism, antioxidant enzyme activity, osmolytes, and disease severity index of leaves with or without the downy mildew disease were measured. Results showed that heat shock significantly decreased the net photosynthetic rate, actual photochemical efficiency, photochemical quenching coefficient, and starch content. Heat shock caused an increase in the stomatal conductance, transpiration rate, antioxidant enzyme activities, total soluble sugar content, sucrose content, soluble protein content and proline content for both healthy leaves and downy mildew infected leaves. These results demonstrate that heat shock activated the transpiration pathway to protect the photosystem from damage due to excess energy in cucumber leaves. Potential resistance mechanisms of plants exposed to heat stress may involve higher osmotic regulation capacity related to an increase of total accumulations of soluble sugar, proline and soluble protein, as well as higher antioxidant enzymes activity in stressed leaves. Heat shock reduced downy mildew disease severity index by more than 50%, and clearly alleviated downy mildew development in the greenhouses. These findings indicate that cucumber may have a complex physiological change to resist short-term heat shock, and suppress the development of the downy mildew disease. PMID:27065102

  14. Effects of Heat Shock on Photosynthetic Properties, Antioxidant Enzyme Activity, and Downy Mildew of Cucumber (Cucumis sativus L.).

    PubMed

    Ding, Xiaotao; Jiang, Yuping; Hao, Ting; Jin, Haijun; Zhang, Hongmei; He, Lizhong; Zhou, Qiang; Huang, Danfeng; Hui, Dafeng; Yu, Jizhu

    2016-01-01

    Heat shock is considered an abiotic stress for plant growth, but the effects of heat shock on physiological responses of cucumber plant leaves with and without downy mildew disease are still not clear. In this study, cucumber seedlings were exposed to heat shock in greenhouses, and the responses of photosynthetic properties, carbohydrate metabolism, antioxidant enzyme activity, osmolytes, and disease severity index of leaves with or without the downy mildew disease were measured. Results showed that heat shock significantly decreased the net photosynthetic rate, actual photochemical efficiency, photochemical quenching coefficient, and starch content. Heat shock caused an increase in the stomatal conductance, transpiration rate, antioxidant enzyme activities, total soluble sugar content, sucrose content, soluble protein content and proline content for both healthy leaves and downy mildew infected leaves. These results demonstrate that heat shock activated the transpiration pathway to protect the photosystem from damage due to excess energy in cucumber leaves. Potential resistance mechanisms of plants exposed to heat stress may involve higher osmotic regulation capacity related to an increase of total accumulations of soluble sugar, proline and soluble protein, as well as higher antioxidant enzymes activity in stressed leaves. Heat shock reduced downy mildew disease severity index by more than 50%, and clearly alleviated downy mildew development in the greenhouses. These findings indicate that cucumber may have a complex physiological change to resist short-term heat shock, and suppress the development of the downy mildew disease.

  15. Effects of Heat Shock on Photosynthetic Properties, Antioxidant Enzyme Activity, and Downy Mildew of Cucumber (Cucumis sativus L.).

    PubMed

    Ding, Xiaotao; Jiang, Yuping; Hao, Ting; Jin, Haijun; Zhang, Hongmei; He, Lizhong; Zhou, Qiang; Huang, Danfeng; Hui, Dafeng; Yu, Jizhu

    2016-01-01

    Heat shock is considered an abiotic stress for plant growth, but the effects of heat shock on physiological responses of cucumber plant leaves with and without downy mildew disease are still not clear. In this study, cucumber seedlings were exposed to heat shock in greenhouses, and the responses of photosynthetic properties, carbohydrate metabolism, antioxidant enzyme activity, osmolytes, and disease severity index of leaves with or without the downy mildew disease were measured. Results showed that heat shock significantly decreased the net photosynthetic rate, actual photochemical efficiency, photochemical quenching coefficient, and starch content. Heat shock caused an increase in the stomatal conductance, transpiration rate, antioxidant enzyme activities, total soluble sugar content, sucrose content, soluble protein content and proline content for both healthy leaves and downy mildew infected leaves. These results demonstrate that heat shock activated the transpiration pathway to protect the photosystem from damage due to excess energy in cucumber leaves. Potential resistance mechanisms of plants exposed to heat stress may involve higher osmotic regulation capacity related to an increase of total accumulations of soluble sugar, proline and soluble protein, as well as higher antioxidant enzymes activity in stressed leaves. Heat shock reduced downy mildew disease severity index by more than 50%, and clearly alleviated downy mildew development in the greenhouses. These findings indicate that cucumber may have a complex physiological change to resist short-term heat shock, and suppress the development of the downy mildew disease. PMID:27065102

  16. 24 CFR 200.950 - Building product standards and certification program for solar water heating system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... certification program for solar water heating system. 200.950 Section 200.950 Housing and Urban Development... solar water heating system. (a) Applicable standards. (1) All solar water heating systems shall be designed, manufactured, and tested in compliance with Solar Rating and Certification Corporation...

  17. 24 CFR 200.950 - Building product standards and certification program for solar water heating system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... certification program for solar water heating system. 200.950 Section 200.950 Housing and Urban Development... solar water heating system. (a) Applicable standards. (1) All solar water heating systems shall be designed, manufactured, and tested in compliance with Solar Rating and Certification Corporation...

  18. 78 FR 63410 - Energy Conservation Program for Consumer Products: Test Procedures for Direct Heating Equipment...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-10-24

    ... into two groups: those used as the primary heating source for the home and those not used for this... of unvented heaters that are not used as the primary heating source for the home. For unvented heaters that are used as the primary heating source for the home, there is a calculation of annual...

  19. Heat Exchange System Improvement Saves Energy and Improves Production at a Winery

    SciTech Connect

    2001-08-01

    In 2000, Fetzer Vineyards implemented a project to improve its process heating cycle at its Hopland Winery in Hopland, California. In an effort to reduce expenditures on natural gas, Fetzer reviewed their wine process heating cycle and discovered that they could reduce their natural gas purchases and improve efficiency by installing a heat exchanger.

  20. 24 CFR 200.950 - Building product standards and certification program for solar water heating system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... certification program for solar water heating system. 200.950 Section 200.950 Housing and Urban Development... solar water heating system. (a) Applicable standards. (1) All solar water heating systems shall be designed, manufactured, and tested in compliance with Solar Rating and Certification Corporation...

  1. 24 CFR 200.950 - Building product standards and certification program for solar water heating system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... certification program for solar water heating system. 200.950 Section 200.950 Housing and Urban Development... solar water heating system. (a) Applicable standards. (1) All solar water heating systems shall be designed, manufactured, and tested in compliance with Solar Rating and Certification Corporation...

  2. 24 CFR 200.950 - Building product standards and certification program for solar water heating system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... certification program for solar water heating system. 200.950 Section 200.950 Housing and Urban Development... solar water heating system. (a) Applicable standards. (1) All solar water heating systems shall be designed, manufactured, and tested in compliance with Solar Rating and Certification Corporation...

  3. Methods for determining enzymatic activity comprising heating and agitation of closed volumes

    DOEpatents

    Thompson, David Neil; Henriksen, Emily DeCrescenzo; Reed, David William; Jensen, Jill Renee

    2016-03-15

    Methods for determining thermophilic enzymatic activity include heating a substrate solution in a plurality of closed volumes to a predetermined reaction temperature. Without opening the closed volumes, at least one enzyme is added, substantially simultaneously, to the closed volumes. At the predetermined reaction temperature, the closed volumes are agitated and then the activity of the at least one enzyme is determined. The methods are conducive for characterizing enzymes of high-temperature reactions, with insoluble substrates, with substrates and enzymes that do not readily intermix, and with low volumes of substrate and enzyme. Systems for characterizing the enzymes are also disclosed.

  4. THE ROLE OF MAGNETIC TOPOLOGY IN THE HEATING OF ACTIVE REGION CORONAL LOOPS

    SciTech Connect

    Lee, J.-Y.; Reeves, Katharine K.; Korreck, K. E.; Golub, L.; DeLuca, E. E.; Barnes, Graham; Leka, K. D.

    2010-11-10

    We investigate the evolution of coronal loop emission in the context of the coronal magnetic field topology. New modeling techniques allow us to investigate the magnetic field structure and energy release in active regions (ARs). Using these models and high-resolution multi-wavelength coronal observations from the Transition Region and Coronal Explorer and the X-ray Telescope on Hinode, we are able to establish a relationship between the light curves of coronal loops and their associated magnetic topologies for NOAA AR 10963. We examine loops that show both transient and steady emission, and we find that loops that show many transient brightenings are located in domains associated with a high number of separators. This topology provides an environment for continual impulsive heating events through magnetic reconnection at the separators. A loop with relatively constant X-ray and EUV emission, on the other hand, is located in domains that are not associated with separators. This result implies that larger-scale magnetic field reconnections are not involved in heating plasma in these regions, and the heating in these loops must come from another mechanism, such as small-scale reconnections (i.e., nanoflares) or wave heating. Additionally, we find that loops that undergo repeated transient brightenings are associated with separators that have enhanced free energy. In contrast, we find one case of an isolated transient brightening that seems to be associated with separators with a smaller free energy.

  5. Naphthalene Planar Laser-Induced Fluorescence Imaging of Orion Multi-Purpose Crew Vehicle Heat Shield Ablation Products

    NASA Astrophysics Data System (ADS)

    Combs, Christopher S.; Clemens, Noel T.; Danehy, Paul M.

    2013-11-01

    The Orion Multi-Purpose Crew Vehicle (MPCV) calls for an ablative heat shield. In order to better design this heat shield and others that will undergo planetary entry, an improved understanding of the ablation process is required. Given that ablation is a multi-physics process involving heat and mass transfer, codes aiming to predict heat shield ablation are in need of experimental data pertaining to the turbulent transport of ablation products for validation. At The University of Texas at Austin, a technique is being developed that uses planar laser-induced fluorescence (PLIF) of a low-temperature sublimating ablator (naphthalene) to visualize the transport of ablation products in a supersonic flow. Since ablation at reentry temperatures can be difficult to recreate in a laboratory setting it is desirable to create a limited physics problem and simulate the ablation process at relatively low temperature conditions using naphthalene. A scaled Orion MPCV model with a solid naphthalene heat shield has been tested in a Mach 5 wind tunnel at various angles of attack in the current work. PLIF images have shown high concentrations of scalar in the capsule wake region, intermittent turbulent structures on the heat shield surface, and interesting details of the capsule shear layer structure. This work was supported by a NASA Office of the Chief Technologist's Space Technology Research Fellowship (NNX11AN55H).

  6. On the existence of another source of heat production for the earth and planets, and its connection with gravitomagnetism.

    PubMed

    Elbeze, Alexandre Chaloum

    2013-01-01

    Recent revised estimates of the Earth's surface heat flux are in the order of 47 TW. Given that its internal radiogenic (mantle and crust) heat production is estimated to be around 20 TW, the Earth has a thermal deficit of around 27 TW. This article will try to show that the action of the gravitational field of the Sun on the rotating masses of the Earth is probably the source of another heat production in order of 54TW, which would satisfy the thermal balance of our celestial body and probably explain the reduced heat flow Qo. We reach this conclusion within the framework of gravitation implied by Einstein's special and general relativity theory (SR, GR). Our results show that it might possible, in principle, to calculate the heat generated by the action of the gravitational field of celestial bodies on the Earth and planets of the Solar System (a phenomenon that is different to that of the gravitational tidal effect from the Sun and the Moon). This result should help physicists to improve and develop new models of the Earth's heat balance, and suggests that contrary to cooling, the Earth is in a phase of thermal balance, or even reheating. PMID:24255828

  7. On the existence of another source of heat production for the earth and planets, and its connection with gravitomagnetism.

    PubMed

    Elbeze, Alexandre Chaloum

    2013-01-01

    Recent revised estimates of the Earth's surface heat flux are in the order of 47 TW. Given that its internal radiogenic (mantle and crust) heat production is estimated to be around 20 TW, the Earth has a thermal deficit of around 27 TW. This article will try to show that the action of the gravitational field of the Sun on the rotating masses of the Earth is probably the source of another heat production in order of 54TW, which would satisfy the thermal balance of our celestial body and probably explain the reduced heat flow Qo. We reach this conclusion within the framework of gravitation implied by Einstein's special and general relativity theory (SR, GR). Our results show that it might possible, in principle, to calculate the heat generated by the action of the gravitational field of celestial bodies on the Earth and planets of the Solar System (a phenomenon that is different to that of the gravitational tidal effect from the Sun and the Moon). This result should help physicists to improve and develop new models of the Earth's heat balance, and suggests that contrary to cooling, the Earth is in a phase of thermal balance, or even reheating.

  8. Superoxide Anion Production by Human Neutrophils Activated by Trichomonas vaginalis

    PubMed Central

    Song, Hyun-Ouk

    2013-01-01

    Neutrophils are the predominant inflammatory cells found in vaginal discharges of patients infected with Trichomonas vaginalis. In this study, we examined superoxide anion (O2.-) production by neutrophils activated by T. vaginalis. Human neutrophils produced superoxide anions when stimulated with either a lysate of T. vaginalis, its membrane component (MC), or excretory-secretory product (ESP). To assess the role of trichomonad protease in production of superoxide anions by neutrophils, T. vaginalis lysate, ESP, and MC were each pretreated with a protease inhibitor cocktail before incubation with neutrophils. Superoxide anion production was significantly decreased by this treatment. Trichomonad growth was inhibited by preincubation with supernatants of neutrophils incubated for 3 hr with T. vaginalis lysate. Furthermore, myeloperoxidase (MPO) production by neutrophils was stimulated by live trichomonads. These results indicate that the production of superoxide anions and MPO by neutrophils stimulated with T. vaginalis may be a part of defense mechanisms of neutrophils in trichomoniasis. PMID:24039294

  9. Superoxide anion production by human neutrophils activated by Trichomonas vaginalis.

    PubMed

    Song, Hyun-Ouk; Ryu, Jae-Sook

    2013-08-01

    Neutrophils are the predominant inflammatory cells found in vaginal discharges of patients infected with Trichomonas vaginalis. In this study, we examined superoxide anion (O2 (.-)) production by neutrophils activated by T. vaginalis. Human neutrophils produced superoxide anions when stimulated with either a lysate of T. vaginalis, its membrane component (MC), or excretory-secretory product (ESP). To assess the role of trichomonad protease in production of superoxide anions by neutrophils, T. vaginalis lysate, ESP, and MC were each pretreated with a protease inhibitor cocktail before incubation with neutrophils. Superoxide anion production was significantly decreased by this treatment. Trichomonad growth was inhibited by preincubation with supernatants of neutrophils incubated for 3 hr with T. vaginalis lysate. Furthermore, myeloperoxidase (MPO) production by neutrophils was stimulated by live trichomonads. These results indicate that the production of superoxide anions and MPO by neutrophils stimulated with T. vaginalis may be a part of defense mechanisms of neutrophils in trichomoniasis. PMID:24039294

  10. Superoxide anion production by human neutrophils activated by Trichomonas vaginalis.

    PubMed

    Song, Hyun-Ouk; Ryu, Jae-Sook

    2013-08-01

    Neutrophils are the predominant inflammatory cells found in vaginal discharges of patients infected with Trichomonas vaginalis. In this study, we examined superoxide anion (O2 (.-)) production by neutrophils activated by T. vaginalis. Human neutrophils produced superoxide anions when stimulated with either a lysate of T. vaginalis, its membrane component (MC), or excretory-secretory product (ESP). To assess the role of trichomonad protease in production of superoxide anions by neutrophils, T. vaginalis lysate, ESP, and MC were each pretreated with a protease inhibitor cocktail before incubation with neutrophils. Superoxide anion production was significantly decreased by this treatment. Trichomonad growth was inhibited by preincubation with supernatants of neutrophils incubated for 3 hr with T. vaginalis lysate. Furthermore, myeloperoxidase (MPO) production by neutrophils was stimulated by live trichomonads. These results indicate that the production of superoxide anions and MPO by neutrophils stimulated with T. vaginalis may be a part of defense mechanisms of neutrophils in trichomoniasis.

  11. Characterization of Hydraulic Active Fractures in a Dolostone Aquifer Using Heat and Contaminants As Tracers

    NASA Astrophysics Data System (ADS)

    Maldaner, C. H.; Coleman, T. I.; Parker, B. L.; Cherry, J. A.

    2014-12-01

    The number of hydraulically active fractures serving as advective contaminant migration pathways facilitating plume migration in fractured rock aquifers cannot be determined with confidence from indirect means such as visual inspection of core, borehole geophysics, and is only inferred from hydraulic tests. However, the position of depth-discrete hydraulic activity may be determined using contaminants or heat as tracers yet spatially detailed profile measurement techniques are required without imparting measurement bias of an open borehole. Contaminant concentration profiles from numerous samples along continuous core from a site contaminated since the early 1980's and heat injection in the sealed boreholes with high resolution profile monitoring are used to characterize the fracture network . Heat pulse tests using active distributed temperature sensing (DTS) were conducted in coreholes sealed with an impermeable flexible liner manufactured by FLUTe (Santa Fe, NM) to detect hydraulically active fracture zones. Using a Silixa ULTIMA-HSTM DTS, temperature data was acquired every 12.6 cm along an optic fiber cable with a spatial resolution of 29 cm. Temperature precision is on the order of 0.02°C for averaged measurements collected over 5 minute intervals. The test consisted of heating the measurement cable for 4 hours and monitoring the cooling process for over 8 hours. The resulting dataset consists of high-resolution temperature profiles at five-minute time steps during the test period. Dolostone rock composes most of the lithology units of the corehole, therefore it is unlikely that there are significant variations in rock thermal diffusivity. Multiple, successive temperature profiles were used to identify depth-discrete, hydraulically active flow zones with varying transmissivity based on different rates of heat dissipation. These variations were then compared with independent datasets including detected concentrations of contaminants in numerous rock core

  12. Enhanced detection of hydraulically active fractures by temperature profiling in lined heated bedrock boreholes

    NASA Astrophysics Data System (ADS)

    Pehme, P. E.; Parker, B. L.; Cherry, J. A.; Molson, J. W.; Greenhouse, J. P.

    2013-03-01

    SummaryThe effectiveness of borehole profiling using a temperature probe for identifying hydraulically active fractures in rock has improved due to the combination of two advances: improved temperature sensors, with resolution on the order of 0.001 °C, and temperature profiling within water inflated flexible impermeable liners used to temporarily seal boreholes from hydraulic cross-connection. The open-hole cross-connection effects dissipate after inflation, so that both the groundwater flow regime and the temperature distribution return to the ambient (background) condition. This paper introduces a third advancement: the use of an electrical heating cable that quickly increases the temperature of the entire static water column within the lined hole and thus places the entire borehole and its immediate vicinity into thermal disequilibrium with the broader rock mass. After heating for 4-6 h, profiling is conducted several times over a 24 h period as the temperature returns to background conditions. This procedure, referred to as the Active Line Source (ALS) method, offers two key improvements over prior methods. First, there is no depth limit for detection of fractures with flow. Second, both identification and qualitative comparison of evidence for ambient groundwater flow in fractures is improved throughout the entire test interval. The benefits of the ALS method are demonstrated by comparing results from two boreholes tested to depths of 90 and 120 m in a dolostone aquifer used for municipal water supply and in which most groundwater flow occurs in fractures. Temperature logging in the lined holes shows many fractures in the heterothermic zone both with and without heating, but only the ALS method shows many hydraulically active fractures in the deeper homothermic portion of the hole. The identification of discrete groundwater flow at many depths is supported by additional evidence concerning fracture occurrence, including continuous core visual inspection

  13. Exergy analysis of an integrated solid oxide fuel cell and organic Rankine cycle for cooling, heating and power production

    NASA Astrophysics Data System (ADS)

    Al-Sulaiman, Fahad A.; Dincer, Ibrahim; Hamdullahpur, Feridun

    The study examines a novel system that combined a solid oxide fuel cell (SOFC) and an organic Rankine cycle (ORC) for cooling, heating and power production (trigeneration) through exergy analysis. The system consists of an SOFC, an ORC, a heat exchanger and a single-effect absorption chiller. The system is modeled to produce a net electricity of around 500 kW. The study reveals that there is 3-25% gain on exergy efficiency when trigeneration is used compared with the power cycle only. Also, the study shows that as the current density of the SOFC increases, the exergy efficiencies of power cycle, cooling cogeneration, heating cogeneration and trigeneration decreases. In addition, it was shown that the effect of changing the turbine inlet pressure and ORC pump inlet temperature are insignificant on the exergy efficiencies of the power cycle, cooling cogeneration, heating cogeneration and trigeneration. Also, the study reveals that the significant sources of exergy destruction are the ORC evaporator, air heat exchanger at the SOFC inlet and heating process heat exchanger.

  14. Charged fusion product loss measurements using nuclear activation

    SciTech Connect

    Bonheure, G.; Hult, M.; Gonzalez de Orduna, R.; W