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Sample records for activity reducing power

  1. Effect of Lead stress on phosphatase activity and reducing power assay of Triticum aestivum.

    PubMed

    Gubrelay, U; Agnihotri, R K; Shrotriya, S; Sharma, R

    2015-01-01

    Lead (Pb) is a highly toxic heavy metal for both plants and animals; the environment is increasingly polluted with heavy metals and reduces crop productivity. Plants possess homeostatic mechanisms that allow them to keep correct concentrations of essential metal ions in cellular compartments and to minimize the damaging effects of an excess of nonessential ones. One of their adverse effects on plants are the generation of harmful active oxygen species, leading to oxidative stress and the antioxidative activity seems to be of fundamental importance for adaptive response of plant against environmental stress. The present study explores the effects of lead (soil treated twice/ week) with (10, 30 and 60 mM) on the specific activities of phosphatases which might lead to reducing power assay in (Triticum aestivum PBW344) seedling. A significant decrease in the redox potential of shoot compared to root was observed at the similar concentration of lead. A similar trend on leaves was also noted. Acid and alkaline phosphatase activities were significantly higher in roots than in shoot at all the three concentration of lead i.e. 10, 30 and 60 mM, compared to controls. The above mentioned changes were more pronounced at 60 mM concentration of lead than two other concentrations. These results lead us to suggest that increased lead concentration in soil might lead to adverse effects on plant growth and phosphatase activities. PMID:26107501

  2. Powered hip exoskeletons can reduce the user's hip and ankle muscle activations during walking.

    PubMed

    Lenzi, Tommaso; Carrozza, Maria Chiara; Agrawal, Sunil K

    2013-11-01

    In this paper, we study the human locomotor adaptation to the action of a powered exoskeleton providing assistive torque at the user's hip during walking. To this end, we propose a controller that provides the user's hip with a fraction of the nominal torque profile, adapted to the specific gait features of the user from Winter's reference data . The assistive controller has been implemented on the ALEX II exoskeleton and tested on ten healthy subjects. Experimental results show that when assisted by the exoskeleton, users can reduce the muscle effort compared to free walking. Despite providing assistance only to the hip joint, both hip and ankle muscles significantly reduced their activation, indicating a clear tradeoff between hip and ankle strategy to propel walking. PMID:23529105

  3. Reduced shear power spectrum

    SciTech Connect

    Dodelson, Scott; Shapiro, Charles; White, Martin J.; /UC, Berkeley, Astron. Dept. /UC, Berkeley

    2005-08-01

    Measurements of ellipticities of background galaxies are sensitive to the reduced shear, the cosmic shear divided by (1-{kappa}) where {kappa} is the projected density field. They compute the difference between shear and reduced shear both analytically and with simulations. The difference becomes more important an smaller scales, and will impact cosmological parameter estimation from upcoming experiments. A simple recipe is presented to carry out the required correction.

  4. A power semiconductor test circuit with reduced power requirements

    NASA Technical Reports Server (NTRS)

    Been, J. F.

    1970-01-01

    Switching circuit utilizing silicon controlled rectifier reduces input power requirements normally associated with testing power semiconductors in an operational type mode. Circuit alleviates problems of inaccessibility, lack of large amounts of power, physical size of power resistors, wiring, and heat generation.

  5. Active structures to reduce torsional vibrations

    NASA Astrophysics Data System (ADS)

    Matthias, M.; Schlote, D.; Atzrodt, H.

    2013-03-01

    This paper describes the development of different active measures to reduce torsional vibrations in power trains. The measures are based on concepts developed for active mounts to reduce the transmission of structure-borne sound. To show the potential of these active measures and investigate their mode of operation to influence torsional vibrations, numerical simulations of powertrains with different active measures were done. First experimental results from tests on an experimental (reduced size) power train were used to align the numerical models. The work was done within the project 'LOEWE-Zentrum AdRIA: Adaptronik - Research, Innovation, Application' funded by the German federal state of Hessen, and the Project AKTos: 'Active control of torsional vibrations by coupling elements' placed in the research Framework program 'Navigation and Maritime Technology for the 21st Century' funded by the German Federal Ministry of Economics and Technology.

  6. Heisenberg uncertainty in reduced power algebras

    NASA Astrophysics Data System (ADS)

    Rosinger, Elemér E.

    2012-12-01

    The Heisenberg uncertainty relation is known to be obtainable by a purely mathematical argument. Based on that fact, here it is shown that the Heisenberg uncertainty relation remains valid when Quantum Mechanics is re-formulated within far wider frameworks of scalars, namely, within one or the other of the infinitely many reduced power algebras which can replace the usual real numbers R, or complex numbers C. Three possible major advantages in Physics of such a reformulation are: 1) the disappearance of the well known and hard to deal with problem of the so called "infinities in Physics", 2) the possibilitiy to have infinitely many "levels of precision" instead of the only one existing at present, 3) the possibility to model "hierarchies of Planck constants", [2]. Last and not least, the scalars given by reduced power algebras contain as a particular case those obtained by Nonstandard Analysis, yet they are far more simple and easy to deal with, being in fact on the level of a first course in Algebra. A detailed version of this paper can be found in arxiv:0901.4825.

  7. Active Power Controls from Wind Power: Bridging the Gaps

    SciTech Connect

    Ela, E.; Gevorgian, V.; Fleming, P.; Zhang, Y. C.; Singh, M.; Muljadi, E.; Scholbrook, A.; Aho, J.; Buckspan, A.; Pao, L.; Singhvi, V.; Tuohy, A.; Pourbeik, P.; Brooks, D.; Bhatt, N.

    2014-01-01

    This paper details a comprehensive study undertaken by the National Renewable Energy Laboratory, Electric Power Research Institute, and the University of Colorado to understand how the contribution of wind power providing active power control (APC) can benefit the total power system economics, increase revenue streams, improve the reliability and security of the power system, and provide superior and efficient response while reducing any structural and loading impacts that may reduce the life of the wind turbine or its components. The study includes power system simulations, control simulations, and actual field tests using turbines at NREL's National Wind Technology Center (NWTC). The study focuses on synthetic inertial control, primary frequency control, and automatic generation control, and analyzes timeframes ranging from milliseconds to minutes to the lifetime of wind turbines, locational scope ranging from components of turbines to large wind plants to entire synchronous interconnections, and additional topics ranging from economics to power system engineering to control design.

  8. Using Geothermal Electric Power to Reduce Carbon Footprint

    NASA Astrophysics Data System (ADS)

    Crombie, George W.

    Human activities, including the burning of fossil fuels, increase carbon dioxide levels, which contributes to global warming. The research problem of the current study examined if geothermal electric power could adequately replace fossil fuel by 2050, thus reducing the emissions of carbon dioxide while avoiding potential problems with expanding nuclear generation. The purpose of this experimental research was to explore under what funding and business conditions geothermal power could be exploited to replace fossil fuels, chiefly coal. Complex systems theory, along with network theory, provided the theoretical foundation for the study. Research hypotheses focused on parameters, such as funding level, exploration type, and interfaces with the existing power grid that will bring the United States closest to the goal of phasing out fossil based power by 2050. The research was conducted by means of computer simulations, using agent-based modeling, wherein data were generated and analyzed. The simulations incorporated key information about the location of geothermal resources, exploitation methods, transmission grid limits and enhancements, and demand centers and growth. The simulation suggested that rapid and aggressive deployment of geothermal power plants in high potential areas, combined with a phase out of coal and nuclear plants, would produce minimal disruptions in the supply of electrical power in the United States. The implications for social change include reduced risk of global warming for all humans on the planet, reduced pollution due to reduction or elimination of coal and nuclear power, increased stability in energy supply and prices in the United States, and increased employment of United States citizens in jobs related to domestic energy production.

  9. Engineering innovation to reduce wind power COE

    SciTech Connect

    Ammerman, Curtt Nelson

    2011-01-10

    There are enough wind resources in the US to provide 10 times the electric power we currently use, however wind power only accounts for 2% of our total electricity production. One of the main limitations to wind use is cost. Wind power currently costs 5-to-8 cents per kilowatt-hour, which is more than twice the cost of electricity generated by burning coal. Our Intelligent Wind Turbine LDRD Project is applying LANL's leading-edge engineering expertise in modeling and simulation, experimental validation, and advanced sensing technologies to challenges faced in the design and operation of modern wind turbines.

  10. Reducing Stepping-Motor Power Consumption

    NASA Technical Reports Server (NTRS)

    Williams, C. J.

    1985-01-01

    Direct-current stepping motors used in computer peripherals, process control, and precision remote-positioning equipment constantly dissipate power and create heat even when not moving. Circuit design energizes stepper motor only when pulses are present on control input.

  11. Reducing power consumption in zinc electrowinning

    NASA Astrophysics Data System (ADS)

    Parada T, F.; Asselin, E.

    2009-10-01

    Approximately 7 million tons per annum of zinc are produced globally by traditional electrowinning which is a power intensive process. Power consumption is directly proportional to cell voltage which is thermodynamically limited to the potential difference between the oxygen evolution and zinc reduction reactions. This article summarizes several novel approaches which are currently under investigation/or the reduction of power consumption in zinc electrowinning and which focus on alternative anode reactions. In particular, methanol, formic acid, ferrous to ferric and hydrogen oxidation as anodic reactions are examined. There remain several important materials, engineering, and process challenges associated with the new approaches which are reviewed in this article. However, given the current and anticipated future cost of energy, further research is warranted.

  12. Using government purchasing power to reduce equipment standby power

    SciTech Connect

    Harris, Jeffrey; Meier, Alan; Bartholomew, Emily; Thomas, Alison; Glickman, Joan; Ware Michelle

    2003-03-03

    Although the government sector represents only 10 to 15 percent of the economy in most countries, carefully targeted public procurement can play a significant role in market transformation through its influence on both buyers and suppliers. Government leadership in energy-efficient purchasing can set an example for other buyers, while creating opportunities for leading manufacturers and distributors to increase their sales and market share by offering energy-efficient products at competitive prices. Under proper circumstances, a highly visible government purchasing policy can have a disproportionately large influence on the market for efficient products. In the United States, President Bush signed an Executive Order in 2001 directing all federal agencies to buy products with low standby power (1 watt or less where possible). This represents a deliberate choice to use government purchasing - rather than regulations or incentives - as a market-based strategy to encourage energy savings. It also builds upon existing efforts to encourage Federal purchase of energy-efficient products (Energy Star products and others in the top 25th percentile of efficiency). This paper summarizes the Federal Energy Management Program s first 18 months of experience in implementing this Executive Order, including analysis of data on standby power, interactions with manufacturers and industry groups, and the relationship between these efforts and other federal programs concerning product labelling, testing, rating, and efficiency standards. After five years of implementing low-standby power purchasing, we estimate energy savings for federal agencies alone at about 230 GWh/year (worth US$14 million), with spillover effects on the broader market that will save all US consumers nearly 4000 GWh/year (US$300 million).

  13. Reducing Skin Picking via Competing Activities

    ERIC Educational Resources Information Center

    Lane, Kathleen Lynne; Thompson, Ada; Reske, Cara L.; Gable, Lauren M.; Barton-Arwood, Sally

    2006-01-01

    This study examined the outcomes of a competing activities intervention to decrease skin picking exhibited by a 9-year-old student with comorbid diagnoses. Results of an ABCBAB design revealed that the use of student-selected manipulatives resulted in reduced skin picking. (Contains 1 figure.)

  14. Power and death: Mortality salience increases power seeking while feeling powerful reduces death anxiety.

    PubMed

    Belmi, Peter; Pfeffer, Jeffrey

    2016-05-01

    According to Terror Management Theory, people respond to reminders of mortality by seeking psychological security and bolstering their self-esteem. Because previous research suggests that having power can provide individuals a sense of security and self-worth, we hypothesize that mortality salience leads to an increased motivation to acquire power, especially among men. Study 1 found that men (but not women) who wrote about their death reported more interest in acquiring power. Study 2A and Study 2B demonstrated that when primed with reminders of death, men (but not women) reported behaving more dominantly during the subsequent week, while both men and women reported behaving more prosocially during that week. Thus, mortality salience prompts people to respond in ways that help them manage their death anxiety but in ways consistent with normative gender expectations. Furthermore, Studies 3-5 showed that feeling powerful reduces anxiety when mortality is salient. Specifically, we found that when primed to feel more powerful, both men and women experienced less mortality anxiety. (PsycINFO Database Record PMID:26867106

  15. Study examines sulfate-reducing bacteria activity

    SciTech Connect

    McElhiney, J.E.; Hardy, J.A.; Rizk, T.Y.; Stott, J.F.D.; Eden, R.D.

    1996-12-09

    Low-sulfate seawater injection can reduce the potential of an oil reservoir turning sour because of sulfate-reducing bacteria. Sulfate-reducing bacteria (SRB) convert sulfate ions in seawater used in waterflooding into sulfide with the concomitant oxidation of a carbon source. A recent study at Capcis investigated the efficiency of SRB under various conditions of sulfate limitation. This study was conducted in a flowing bioreactor at 2,000 psia with different temperature zones (mesophilic 35 C and thermophilic 60--80 C). The study mixed microfloral populations derived from real North Sea-produced fluids, and included an active population of marine methanogenic bacteria present to provide competition for the available carbon sources. In general, results showed that SRB continue to convert sulfate to sulfide in stoichiometric quantities without regard to absolute concentrations. The paper discusses the results and recommends nanofiltration of seawater for ``sweet`` reservoirs.

  16. Active Power Control from Wind Power (Presentation)

    SciTech Connect

    Ela, E.; Brooks, D.

    2011-04-01

    In order to keep the electricity grid stable and the lights on, the power system relies on certain responses from its generating fleet. This presentation evaluates the potential for wind turbines and wind power plants to provide these services and assist the grid during critical times.

  17. Reducing Power Consumption in Core Wavelength Division Multiplexing Optical Networks

    NASA Astrophysics Data System (ADS)

    Coiro, Angelo; Valenti, Alessandro; Matera, Francesco; Settembre, Marina

    2011-06-01

    This work proposes some heuristic criteria aiming at saving energy by efficiently switching off optical fibers in generalized multi-protocol label switching-controlled optical networks during low traffic load periods and by taking into account network equipment power consumption. Simulations show that up to 80% of energy can be saved when the traffic is reduced by 20% with respect to its maximum. The impact of network design parameters is also investigated.

  18. Doubled power density from salinity gradients at reduced intermembrane distance.

    PubMed

    Vermaas, David A; Saakes, Michel; Nijmeijer, Kitty

    2011-08-15

    The mixing of sea and river water can be used as a renewable energy source. The Gibbs free energy that is released when salt and fresh water mix can be captured in a process called reverse electrodialysis (RED). This research investigates the effect of the intermembrane distance and the feedwater flow rate in RED as a route to double the power density output. Intermembrane distances of 60, 100, 200, and 485 μm were experimentally investigated, using spacers to impose the intermembrane distance. The generated (gross) power densities (i.e., generated power per membrane area) are larger for smaller intermembrane distances. A maximum value of 2.2 W/m(2) is achieved, which is almost double the maximum power density reported in previous work. In addition, the energy efficiency is significantly higher for smaller intermembrane distances. New improvements need to focus on reducing the pressure drop required to pump the feedwater through the RED-device using a spacerless design. In that case power outputs of more than 4 W per m(2) of membrane area at small intermembrane distances are envisaged. PMID:21736348

  19. Cardiovascular function following reduced aerobic activity

    NASA Technical Reports Server (NTRS)

    Raven, P. B.; Welch-O'Connor, R. M.; Shi, X.; Blomqvist, C. G. (Principal Investigator)

    1998-01-01

    PURPOSE: The aim of this study was to test the hypothesis that a sustained reduction of physical activity (deconditioning) would alter the cardiovascular regulatory function. METHODS: Nineteen young, healthy volunteers participated in physical deconditioning for a period of 8 wk. Before (pre) and following (post) physical deconditioning, the responses of heart rate (HR), mean arterial pressure (MAP, measured by Finapres), central venous pressure (CVP), stroke volume (SV, Doppler), and forearm blood flow (FBF, plethysmography) were determined during lower body negative pressure (LBNP). The carotid baroreflex (CBR) function was assessed using a train of pulsatile neck pressure (NP) and suction, and the aortic baroreflex control of HR was assessed during steady-state phenylephrine (PE) infusion superimposed by LBNP and NP to counteract the PE increased CVP and carotid sinus pressure, respectively. RESULTS: Active physical deconditioning significantly decreased maximal oxygen uptake (-7%) and LBNP tolerance (-13%) without a change in baseline hemodynamics. Plasma volume (-3% at P = 0.135), determined by Evans Blue dilution, and blood volume (-4% at P = 0.107) were not significantly altered. During LBNP -20 to -50 torr, there was a significantly greater drop of SV per unit decrease in CVP in the post- (14.7 +/- 1.6%/mm Hg) than predeconditioning (11.2 +/- 0.7%/mm Hg) test accompanied by a greater tachycardia. Deconditioning increased the aortic baroreflex sensitivity (pre vs post: -0.61 +/- 0.12 vs -0.84 +/- 0.14 bpm.mm-1 Hg, P = 0.009) and the slope of forearm vascular resistance (calculated from [MAP-CVP]/FBF) to CVP (-2.75 +/- 0.26 vs -4.94 +/- 0.97 PRU/mm Hg, P = 0.086). However, neither the CBR-HR (-0.28 +/- 0.03 VS -0.39 +/- 0.10 bpm.mm-1 Hg) nor the CBR-MAP (-0.37 +/- 0.16 vs -0.25 +/- 0.07 mm Hg/mm Hg) gains were statistically different between pre- and postdeconditioning. CONCLUSIONS: We concluded that the functional modification of the cardiac pressure

  20. Wave activated power generation system

    SciTech Connect

    Ono, Y.

    1983-08-09

    A wave activated power generation system of the float type is disclosed, comprising at least one piston-cylinder device having an anchored cylinder and a piston slidable in the cylinder and cooperating with the cylinder to form a pumping chamber above the piston and a low pressure chamber below the piston. The cylinder has an intake port and an exhaust port both formed at an upper port thereof to communicate with the pumping chamber and each provided with a check valve. A float is connected through a cable to the piston of the piston- cylinder device. A pair of fluid storages are connected to the intake port and the exhaust port of the pumping chamber, respectively. A waterwheel generator is driven by the fluid flowing from one of the fluid storages to another. A pressure regulating device is connected to the low pressure chamber so as to maintain the low pressure chamber at a pressure lower than the pressure in the pumping chamber, the difference in pressure ceaselessly applying a downward force on the piston to keep the cable in a tensed condition.

  1. Process for reducing beta activity in uranium

    DOEpatents

    Briggs, Gifford G.; Kato, Takeo R.; Schonegg, Edward

    1986-10-07

    This invention is a method for lowering the beta radiation hazards associated with the casting of uranium. The method reduces the beta radiation emitted from the as-cast surfaces of uranium ingots. The method also reduces the amount of beta radiation emitters retained on the interiors of the crucibles that have been used to melt the uranium charges and which have undergone cleaning in a remote handling facility. The lowering of the radioactivity is done by scavenging the beta emitters from the molten uranium with a molten mixture containing the fluorides of magnesium and calcium. The method provides a means of collection and disposal of the beta emitters in a manner that reduces radiation exposure to operating personnel in the work area where the ingots are cast and processed.

  2. Process for reducing beta activity in uranium

    DOEpatents

    Briggs, G.G.; Kato, T.R.; Schonegg, E.

    1985-04-11

    This invention is a method for lowering the beta radiation hazards associated with the casting of uranium. The method reduces the beta radiation emitted from the as-cast surfaces of uranium ingots. The method also reduces the amount of beta radiation emitters retained on the interiors of the crucibles that have been used to melt the uranium charges and which undergone cleaning in a remote handling facility. The lowering of the radioactivity is done by scavenging the beta emitters from the molten uranium with a molten mixture containing the fluorides of magnesium and calcium. The method provides a means of collection and disposal of the beta emitters in a manner that reduces radiation exposure to operating personnel in the work area where the ingots are cast and processed. 5 tabs.

  3. Process for reducing beta activity in uranium

    DOEpatents

    Briggs, Gifford G.; Kato, Takeo R.; Schonegg, Edward

    1986-01-01

    This invention is a method for lowering the beta radiation hazards associated with the casting of uranium. The method reduces the beta radiation emitted from the as-cast surfaces of uranium ingots. The method also reduces the amount of beta radiation emitters retained on the interiors of the crucibles that have been used to melt the uranium charges and which have undergone cleaning in a remote handling facility. The lowering of the radioactivity is done by scavenging the beta emitters from the molten uranium with a molten mixture containing the fluorides of magnesium and calcium. The method provides a means of collection and disposal of the beta emitters in a manner that reduces radiation exposure to operating personnel in the work area where the ingots are cast and processed.

  4. Postischemic hyperoxia reduces hippocampal pyruvate dehydrogenase activity

    PubMed Central

    Richards, Erica M.; Rosenthal, Robert E.; Kristian, Tibor; Fiskum, Gary

    2008-01-01

    The pyruvate dehydrogenase complex (PDHC) is a mitochondrial matrix enzyme that catalyzes the oxidative decarboxylation of pyruvate and represents the sole bridge between anaerobic and aerobic cerebral energy metabolism. Previous studies demonstrating loss of PDHC enzyme activity and immunoreactivity during reperfusion after cerebral ischemia suggest that oxidative modifications are involved. This study tested the hypothesis that hyperoxic reperfusion exacerbates loss of PDHC enzyme activity, possibly due to tyrosine nitration or S-nitrosation. We used a clinically relevant canine ventricular fibrillation cardiac arrest model in which, after resuscitation and ventilation on either 100% O2 (hyperoxic) or 21–30% O2 (normoxic), animals were sacrificed at 2 h reperfusion and the brains removed for enzyme activity and immunoreactivity measurements. Animals resuscitated under hyperoxic conditions exhibited decreased PDHC activity and elevated 3-nitrotyrosine immunoreactivity in the hippocampus but not the cortex, compared to nonischemic controls. These measures were unchanged in normoxic animals. In vitro exposure of purified PDHC to peroxynitrite resulted in a dose-dependent loss of activity and increased nitrotyrosine immunoreactivity. These results support the hypothesis that oxidative stress contributes to loss of hippocampal PDHC activity during cerebral ischemia and reperfusion and suggest that PDHC is a target of peroxynitrite. PMID:16716897

  5. Stimuli Reduce the Dimensionality of Cortical Activity.

    PubMed

    Mazzucato, Luca; Fontanini, Alfredo; La Camera, Giancarlo

    2016-01-01

    The activity of ensembles of simultaneously recorded neurons can be represented as a set of points in the space of firing rates. Even though the dimension of this space is equal to the ensemble size, neural activity can be effectively localized on smaller subspaces. The dimensionality of the neural space is an important determinant of the computational tasks supported by the neural activity. Here, we investigate the dimensionality of neural ensembles from the sensory cortex of alert rats during periods of ongoing (inter-trial) and stimulus-evoked activity. We find that dimensionality grows linearly with ensemble size, and grows significantly faster during ongoing activity compared to evoked activity. We explain these results using a spiking network model based on a clustered architecture. The model captures the difference in growth rate between ongoing and evoked activity and predicts a characteristic scaling with ensemble size that could be tested in high-density multi-electrode recordings. Moreover, we present a simple theory that predicts the existence of an upper bound on dimensionality. This upper bound is inversely proportional to the amount of pair-wise correlations and, compared to a homogeneous network without clusters, it is larger by a factor equal to the number of clusters. The empirical estimation of such bounds depends on the number and duration of trials and is well predicted by the theory. Together, these results provide a framework to analyze neural dimensionality in alert animals, its behavior under stimulus presentation, and its theoretical dependence on ensemble size, number of clusters, and correlations in spiking network models. PMID:26924968

  6. Stimuli Reduce the Dimensionality of Cortical Activity

    PubMed Central

    Mazzucato, Luca; Fontanini, Alfredo; La Camera, Giancarlo

    2016-01-01

    The activity of ensembles of simultaneously recorded neurons can be represented as a set of points in the space of firing rates. Even though the dimension of this space is equal to the ensemble size, neural activity can be effectively localized on smaller subspaces. The dimensionality of the neural space is an important determinant of the computational tasks supported by the neural activity. Here, we investigate the dimensionality of neural ensembles from the sensory cortex of alert rats during periods of ongoing (inter-trial) and stimulus-evoked activity. We find that dimensionality grows linearly with ensemble size, and grows significantly faster during ongoing activity compared to evoked activity. We explain these results using a spiking network model based on a clustered architecture. The model captures the difference in growth rate between ongoing and evoked activity and predicts a characteristic scaling with ensemble size that could be tested in high-density multi-electrode recordings. Moreover, we present a simple theory that predicts the existence of an upper bound on dimensionality. This upper bound is inversely proportional to the amount of pair-wise correlations and, compared to a homogeneous network without clusters, it is larger by a factor equal to the number of clusters. The empirical estimation of such bounds depends on the number and duration of trials and is well predicted by the theory. Together, these results provide a framework to analyze neural dimensionality in alert animals, its behavior under stimulus presentation, and its theoretical dependence on ensemble size, number of clusters, and correlations in spiking network models. PMID:26924968

  7. Brown fat activation reduces hypercholesterolaemia and protects from atherosclerosis development

    PubMed Central

    Berbée, Jimmy F. P.; Boon, Mariëtte R; Khedoe, P. Padmini S. J.; Bartelt, Alexander; Schlein, Christian; Worthmann, Anna; Kooijman, Sander; Hoeke, Geerte; Mol, Isabel M.; John, Clara; Jung, Caroline; Vazirpanah, Nadia; Brouwers, Linda P.J.; Gordts, Philip L.S.M.; Esko, Jeffrey D.; Hiemstra, Pieter S.; Havekes, Louis M.; Scheja, Ludger; Heeren, Joerg; Rensen, Patrick C.N.

    2015-01-01

    Brown adipose tissue (BAT) combusts high amounts of fatty acids, thereby lowering plasma triglyceride levels and reducing obesity. However, the precise role of BAT in plasma cholesterol metabolism and atherosclerosis development remains unclear. Here we show that BAT activation by β3-adrenergic receptor stimulation protects from atherosclerosis in hyperlipidemic APOE*3-Leiden.CETP mice, a well-established model for human-like lipoprotein metabolism that unlike hyperlipidemic Apoe−/− and Ldlr−/− mice expresses functional apoE and LDLR. BAT activation increases energy expenditure and decreases plasma triglyceride and cholesterol levels. Mechanistically, we demonstrate that BAT activation enhances the selective uptake of fatty acids from triglyceride-rich lipoproteins into BAT, subsequently accelerating the hepatic clearance of the cholesterol-enriched remnants. These effects depend on a functional hepatic apoE-LDLR clearance pathway as BAT activation in Apoe−/− and Ldlr−/− mice does not attenuate hypercholesterolaemia and atherosclerosis. We conclude that activation of BAT is a powerful therapeutic avenue to ameliorate hyperlipidaemia and protect from atherosclerosis. PMID:25754609

  8. Starved Escherichia coli preserve reducing power under nitric oxide stress.

    PubMed

    Gowers, Glen-Oliver F; Robinson, Jonathan L; Brynildsen, Mark P

    2016-07-15

    Nitric oxide (NO) detoxification enzymes, such as NO dioxygenase (NOD) and NO reductase (NOR), are important to the virulence of numerous bacteria. Pathogens use these defense systems to ward off immune-generated NO, and they do so in environments that contain additional stressors, such as reactive oxygen species, nutrient deprivation, and acid stress. NOD and NOR both use reducing equivalents to metabolically deactivate NO, which suggests that nutrient deprivation could negatively impact their functionality. To explore the relationship between NO detoxification and nutrient deprivation, we examined the ability of Escherichia coli to detoxify NO under different levels of carbon source availability in aerobic cultures. We observed failure of NO detoxification under both carbon source limitation and starvation, and those failures could have arisen from inabilities to synthesize Hmp (NOD of E. coli) and/or supply it with sufficient NADH (preferred electron donor). We found that when limited quantities of carbon source were provided, NO detoxification failed due to insufficient NADH, whereas starvation prevented Hmp synthesis, which enabled cells to maintain their NADH levels. This maintenance of NADH levels under starvation was confirmed to be dependent on the absence of Hmp. Intriguingly, these data show that under NO stress, carbon-starved E. coli are better positioned with regard to reducing power to cope with other stresses than cells that had consumed an exhaustible amount of carbon. PMID:27207837

  9. Study of novel techniques for reducing self-heating effects in SOI power LDMOS

    NASA Astrophysics Data System (ADS)

    Roig, J.; Flores, D.; Hidalgo, S.; Vellvehi, M.; Rebollo, J.; Millán, J.

    2002-12-01

    Self-heating effects in silicon-on-insulator (SOI) power devices have become a serious problem when the active silicon layer thickness is reduced and buried oxide thickness is increased. Hence, if the temperature of the active region rises, the device electrical characteristics can be seriously modified in steady state and transient modes. In order to alleviate the self heating, two novel techniques which lead to a better heat flow from active silicon layer to silicon substrate through the buried oxide layer in SOI power devices are proposed. No significant changes on device electrical characteristics are expected with the inclusion of the novel techniques. The electro-thermal performance of lateral power devices including the proposed techniques is also presented.

  10. Reducing the endotoxic activity of pertussis vaccine.

    PubMed Central

    Bannatyne, R. M.; Cheung, R.

    1981-01-01

    Unadsorbed, regular production pertussis vaccine was treated with polymyxin B sulphate at concentrations of 25, 50 and 100 microgram/ml. The toxic activity of treated and untreated vaccines was compared using both the limulus amoebocyte lysate test and the mouse-weight-gain test. Protective efficacy was also assessed by the mouse protection test. No discernible effect on either toxicity or efficacy of the pertussis vaccine was observed. When the vaccine was treated with 5000 microgram/ml of polymyxin, endotoxic activity assessed by the limulus lysate test appeared to be abolished. PMID:7310121

  11. Shock-activated electrochemical power supplies

    DOEpatents

    Benedick, W.B.; Graham, R.A.; Morosin, B.

    1987-04-20

    A shock-activated electrochemical power supply is provided which is initiated extremely rapidly and which has a long shelf life. Electrochemical power supplies of this invention are initiated much faster than conventional thermal batteries. Power supplies of this invention comprise an inactive electrolyte and means for generating a high-pressure shock wave such that the shock wave is propagated through the electrolyte rendering the electrolyte electrochemically active. 2 figs.

  12. Shock-activated electrochemical power supplies

    DOEpatents

    Benedick, William B.; Graham, Robert A.; Morosin, Bruno

    1988-01-01

    A shock-activated electrochemical power supply is provided which is initiated extremely rapidly and which has a long shelf life. Electrochemical power supplies of this invention are initiated much faster than conventional thermal batteries. Power supplies of this invention comprise an inactive electrolyte and means for generating a high-pressure shock wave such that the shock wave is propagated through the electrolytes rendering the electrolyte electrochemically active.

  13. Shock-activated electrochemical power supplies

    DOEpatents

    Benedick, W.B.; Graham, R.A.; Morosin, B.

    1988-11-08

    A shock-activated electrochemical power supply is provided which is initiated extremely rapidly and which has a long shelf life. Electrochemical power supplies of this invention are initiated much faster than conventional thermal batteries. Power supplies of this invention comprise an inactive electrolyte and means for generating a high-pressure shock wave such that the shock wave is propagated through the electrolytes rendering the electrolyte electrochemically active. 2 figs.

  14. Power to Production: Activity Guide.

    ERIC Educational Resources Information Center

    Massachusetts Univ., Lowell. Tsongas Industrial History Center.

    This field trip program consists of a 90-minute interpretive tour and a 90-minute hands-on workshop. The tour and workshop explore the role of water power in the Industrial Revolution. On the tour, students discover firsthand the unique resources of Lowell, Massachusetts, and the Park, while the workshop brings these historic resources to life as…

  15. Behavioral intervention to reduce AIDS risk activities.

    PubMed

    Kelly, J A; St Lawrence, J S; Hood, H V; Brasfield, T L

    1989-02-01

    Behavior change can curtail the spread of acquired immune deficiency syndrome (AIDS). In this study, 104 gay men with a history of frequent AIDS high-risk behavior completed self-report, self-monitoring, and behavioral measures related to AIDS risk. The sample was randomly divided into experimental and waiting-list control groups. The experimental intervention provided AIDS risk education, cognitive-behavioral self-management training, sexual assertion training, and attention to the development of steady and self-affirming social supports. Experimental group participants greatly reduced their frequency of high-risk sexual practices and increased behavioral skills for refusing sexual coercions, AIDS risk knowledge, and adoption of "safer sex" practices. Change was maintained at the 8-month follow-up. PMID:2925974

  16. Mucin Binding Reduces Colistin Antimicrobial Activity

    PubMed Central

    Huang, Johnny X.; Blaskovich, Mark A. T.; Pelingon, Ruby; Ramu, Soumya; Kavanagh, Angela; Elliott, Alysha G.; Butler, Mark S.

    2015-01-01

    Colistin has found increasing use in treating drug-resistant bacterial lung infections, but potential interactions with pulmonary biomolecules have not been investigated. We postulated that colistin, like aminoglycoside antibiotics, may bind to secretory mucin in sputum or epithelial mucin that lines airways, reducing free drug levels. To test this hypothesis, we measured binding of colistin and other antibiotics to porcine mucin, a family of densely glycosylated proteins used as a surrogate for human sputum and airway mucin. Antibiotics were incubated in dialysis tubing with or without mucin, and concentrations of unbound antibiotics able to penetrate the dialysis tubing were measured over time using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The percentage of antibiotic measured in the dialysate after 4 h in the presence of mucin, relative to the amount without mucin, was 15% for colistin, 16% for polymyxin B, 19% for tobramycin, 52% for ciprofloxacin, and 78% for daptomycin. Antibiotics with the strongest mucin binding had an overall polybasic positive charge, whereas those with comparatively little binding were less basic. When comparing MICs measured with or without added mucin, colistin and polymyxin B showed >100-fold increases in MICs for multiple Gram-negative bacteria. Preclinical evaluation of mucin binding should become a standard procedure when considering the potential pulmonary use of new or existing antibiotics, particularly those with a polybasic overall charge. In the airways, mucin binding may reduce the antibacterial efficacy of inhaled or intravenously administered colistin, and the presence of sub-MIC effective antibiotic concentrations could result in the development of antibiotic resistance. PMID:26169405

  17. Reducing Electrical Power Use with a Performance Based Incentive

    SciTech Connect

    M. Kathleen Nell

    2004-07-01

    This Departmental Energy Management Program (DEMP) funded Model Program Study developed out of a potential DOE-ID Performance Based Incentive for the Idaho National Engineering and Environmental Laboratory (INEEL), lasting from October 2001 through May 2002, which stressed reductions in electrical usage. An analysis of demand usage obtained from monthly INEEL Power Management electric reports revealed reductions in demand from a majority of the site areas. The purpose of this Model Program study was to determine the methods and activities that were used at these site areas to achieve the reductions in demand and to develop these demand reduction methods and activities into a Model Program that could be shared throughout the INEEL and DOE complex-wide for additional demand savings. INEEL Energy Management personnel interviewed contacts from the eight areas which had achieved a consistent reduction in demand during the study period, namely, Idaho Nuclear Technology and Engineering Center (INTEC), Test Area North (TAN), Power Burst Facility (PBF), Test Reactor Area (TRA) including Advanced Test Reactor ATR), Engineering Test Reactor (ETR), and Materials Test Reactor (MTR) areas, Central Facilities Area (CFA), Specific Manufacturing Capability (SMC), Radioactive Waste Management Complex (RWMC), and Argonne National Laboratory-West (ANLW). The information that resulted from the interviews indicated that more than direct demand and energy reduction actions were responsible for the recorded reductions in demand. INEEL Energy Management identified five categories of actions or conditions that contributed to the demand reduction. These categories are Decontamination and Decommissioning (D&D), employee actions, improvements, inactivation for maintenance, and processes. The following information details the findings from the study.

  18. Reduced Variability of Auditory Alpha Activity in Chronic Tinnitus

    PubMed Central

    Schecklmann, Martin; Kreuzer, Peter M.; Vielsmeier, Veronika; Poeppl, Timm B.; Langguth, Berthold

    2014-01-01

    Subjective tinnitus is characterized by the conscious perception of a phantom sound which is usually more prominent under silence. Resting state recordings without any auditory stimulation demonstrated a decrease of cortical alpha activity in temporal areas of subjects with an ongoing tinnitus perception. This is often interpreted as an indicator for enhanced excitability of the auditory cortex in tinnitus. In this study we want to further investigate this effect by analysing the moment-to-moment variability of the alpha activity in temporal areas. Magnetoencephalographic resting state recordings of 21 tinnitus subjects and 21 healthy controls were analysed with respect to the mean and the variability of spectral power in the alpha frequency band over temporal areas. A significant decrease of auditory alpha activity was detected for the low alpha frequency band (8–10 Hz) but not for the upper alpha band (10–12 Hz). Furthermore, we found a significant decrease of alpha variability for the tinnitus group. This result was significant for the lower alpha frequency range and not significant for the upper alpha frequencies. Tinnitus subjects with a longer history of tinnitus showed less variability of their auditory alpha activity which might be an indicator for reduced adaptability of the auditory cortex in chronic tinnitus. PMID:24967106

  19. Quantifying the Geographic Diversity Needed to Reduce Wind Power Variability

    NASA Astrophysics Data System (ADS)

    St Martin, C.; Handschy, M.; Lundquist, J. K.

    2014-12-01

    The variability in wind-generated electricity complicates its integration into the electrical grid at higher penetrations. This variability can be reduced by interconnecting wind farms across large regions. We investigate the effectiveness of this aggregation with two extensive data sets. The first consists of 44 years of hourly 10-m wind speeds from 117 stations spanning distances of 5000 km across Canada from the National Climate Data Archive of Environment Canada. The second dataset consists of four years of 5-minute averaged wind speeds from stations across 350 km of the northwestern US from the Bonneville Power Administration. This study seeks to quantify how time scale affects the drop-off of correlation with distance, and hence statistical independence and the degree of geographic diversity needed to provide smoothing on various time scales. To eliminate non-stationarities, we filter both datasets to remove diurnal cycles and seasonal trends, after which we digitally high-pass filter the data on 0.25-2000 hour timescales relevant to power grid management. The wind speed data are then correlated between stations for each high-pass filter cut-off. In both datasets, the correlations between stations fall to zero with increasing station separation distance. Differences in inter-station azimuthal bearing account for a small but distinct fraction of the wide scatter in correlation vs. distance for the Canadian data set, with stations separated along a line 10° North of East-West being systematically less correlated than those perpendicular to that line. Similarities between these two datasets reveal behavior that, if universal, could be particularly useful for grid management. Both datasets exhibit a correlation length that varies as l = l0(1+25/T)-2, where l0 is the correlation length without high-pass filtering and T is the high-pass cut-off (in hours). Since the inter-site separation needed for statistical independence falls for time scales shorter than 25

  20. On reducing terrorism power: a hint from physics

    NASA Astrophysics Data System (ADS)

    Galam, Serge; Mauger, Alain

    2003-05-01

    The September 11 attack on the US has revealed an unprecedented terrorism worldwide range of destruction. Recently, it has been related to the percolation of worldwide spread passive supporters. This scheme puts the suppression of the percolation effect as the major strategic issue in the fight against terrorism. Accordingly the world density of passive supporters should be reduced below the percolation threshold. In terms of solid policy, it means to neutralize millions of random passive supporters, which is contrary to ethics and out of any sound practical scheme. Given this impossibility we suggest instead a new strategic scheme to act directly on the value of the terrorism percolation threshold itself without harming the passive supporters. Accordingly we identify the space hosting the percolation phenomenon to be a multi-dimensional virtual social space which extends the ground earth surface to include the various independent terrorist-fighting goals. The associated percolating cluster is then found to create long-range ground connections to terrorism activity. We are thus able to modify the percolation threshold pc in the virtual space to reach p

  1. A Student Activity on Visual Resolving Power

    ERIC Educational Resources Information Center

    Warren, T. H.; Henriksen, P. N.; Ramsier, R. D.

    2003-01-01

    We present a simple activity in which students measure the resolving power of their eyes. The approach can be used at various levels of sophistication with students having a wide variety of skills and scientific training. We discuss our experiences using this activity with a class of non-science majors as well as with a group of pre-engineering…

  2. Motor power factor controller with a reduced voltage starter

    NASA Technical Reports Server (NTRS)

    Nola, F. J. (Inventor)

    1981-01-01

    A power factor type motor controller is disclosed in which the conventional power factor constant voltage command signal is replaced during a starting interval with a graduated control voltage. This continuation-impart of a pending patent application (Serial No. 199, 765: Three Phase Factor Controller) provides a means for modifying the operation of the system for a motor start-up interval of 5 to 30 second. Using a ramp generators, an initial ramp-like signal replaces a constant power factor signal supplied by a potentiometer. The ramp-like signal is applied to a 15 terminal where it is summed with an operating power factor signal from phase detectors in order to obtain a control signal for ultimately controlling SCR devices. The SCR devices are turned on at an advancing rate with time responsive to the combination signal described rather than simply a function of a ramp-like signal alone.

  3. Recent Progress of R&D Activities on Reduced Activation Ferritic/Martensitic Steels

    SciTech Connect

    Huang, Q.; Baluc, N.; Dai, Y.; Jitsukawa, S.; Kimura, A.; Konys, J.; Kurtz, Richard J.; Lindau, R.; Muroga, T.; Odette, George R.; Raj, B.; Stoller, Roger E.; Tan, L.; Tanigawa, Hiroyasu; Tavassoli, A,-A.F.; Yamamoto, Takuya; Wan, F.; Wu, Y.

    2013-01-03

    Several types of reduced activation ferritic/martensitic (RAFM) steel have been developed over the past 30 years in China, Europe, India, Japan, Russia and the USA for application in ITER TBM and future fusion DEMO and power reactors. The progress has been particularly important during the past few years with evaluation of mechanical porperties of these steels before and after irradiation and in contact with different cooling media. This paper presents recent RAFM steel results obtained in ITER partner countries in relation with different TBM and DEMO options

  4. Reducing costly zebra mussel infestations at power plants

    SciTech Connect

    Smythe, G.

    1994-10-01

    The fast-spreading-zebra mussel has significant potential to foul intakes and other water systems at North American hydro projects. Chemical controls can be effective in reducing infestations, but most have environmental and other drawbacks. Several non-chemical methods promise to help project operators reduce problems associated with the mussels.

  5. Piezoelectric Power Requirements for Active Vibration Control

    NASA Technical Reports Server (NTRS)

    Brennan, Matthew C.; McGowan, Anna-Maria Rivas

    1997-01-01

    This paper presents a method for predicting the power consumption of piezoelectric actuators utilized for active vibration control. Analytical developments and experimental tests show that the maximum power required to control a structure using surface-bonded piezoelectric actuators is independent of the dynamics between the piezoelectric actuator and the host structure. The results demonstrate that for a perfectly-controlled system, the power consumption is a function of the quantity and type of piezoelectric actuators and the voltage and frequency of the control law output signal. Furthermore, as control effectiveness decreases, the power consumption of the piezoelectric actuators decreases. In addition, experimental results revealed a non-linear behavior in the material properties of piezoelectric actuators. The material non- linearity displayed a significant increase in capacitance with an increase in excitation voltage. Tests show that if the non-linearity of the capacitance was accounted for, a conservative estimate of the power can easily be determined.

  6. Motor power factor controller with a reduced voltage starter

    NASA Technical Reports Server (NTRS)

    Nola, Frank J. (Inventor)

    1983-01-01

    A power factor type motor controller in which the conventional power factor constant voltage command signal is replaced during a starting interval with a graduated control voltage. The present invention adds to the three-phase system of pending application Ser. No. 199,765, filed Oct. 23, 1980, means for modifying the operation of the system for a motor start-up interval of 5 to 30 seconds. The modification is that of providing via ramp generator 174 an initial ramp-like signal which replaces a constant power factor signal supplied by potentiometer 70. The ramp-like signal is applied to terminal 40 where it is summed with an operating power factor signal from phase detectors 32, 34, and 36 to thereby obtain a control signal for ultimately controlling SCR devices 12, 14, and 16 to effect a gradual turn-on of motor 10. The significant difference of the present invention over prior art is that the SCR devices are turned on at an advancing rate with time responsive to the combination signal described rather than simply a function of a ramp-like signal alone. The added signal, the operating power factor signal, enables the production of a control signal which effectively eliminates a prior problem with many motor starting circuits, which is that of accompanying motor instabilities.

  7. Oxytocin reduces amygdala activity, increases social interactions, and reduces anxiety-like behavior irrespective of NMDAR antagonism.

    PubMed

    Sobota, Rosanna; Mihara, Takuma; Forrest, Alexandra; Featherstone, Robert E; Siegel, Steven J

    2015-08-01

    Standard dopamine therapies for schizophrenia are not efficacious for negative symptoms of the disease, including asociality. This reduced social behavior may be due to glutamatergic dysfunction within the amygdala, leading to increased fear and social anxiety. Several studies have demonstrated the prosocial effects of oxytocin in schizophrenia patients. Therefore, this study evaluates the effect of subchronic oxytocin on EEG activity in amygdala of mice during performance of the three-chamber social choice and open field tests following acute ketamine as a model of glutamatergic dysfunction. Oxytocin did not restore social deficits introduced by ketamine but did significantly increase sociality in comparison to the control group. Ketamine had no effect on time spent in the center during the open field trials, whereas oxytocin increased overall center time across all groups, suggesting a reduction in anxiety. Amygdala activity was consistent across all drug groups during social and nonsocial behavioral trials. However, oxytocin reduced overall amygdala EEG power during the two behavioral tasks. Alternatively, ketamine did not significantly affect EEG power throughout the tasks. Decreased EEG power in the amygdala, as caused by oxytocin, may be related to both reduced anxiety and increased social behaviors. Data suggest that separate prosocial and social anxiety pathways may mediate social preference. PMID:26214213

  8. Oxytocin reduces amygdala activity, increases social interactions and reduces anxiety-like behavior irrespective of NMDAR antagonism

    PubMed Central

    Sobota, Rosanna; Mihara, Takuma; Forrest, Alexandra; Featherstone, Robert E.; Siegel, Steven J.

    2015-01-01

    Standard dopamine therapies for schizophrenia are not efficacious for negative symptoms of the disease, including asociality. This reduced social behavior may be due to glutamatergic dysfunction within the amygdala leading to increased fear and social anxiety. Several studies have demonstrated the pro-social effects of oxytocin in schizophrenia patients. Therefore, this study evaluates the effect of sub-chronic oxytocin on electroencephalographic (EEG) activity in amygdala of mice during performance of the three chamber social choice and open field tests following acute ketamine as a model of glutamatergic dysfunction. Oxytocin did not restore social deficits introduced by ketamine, but did significantly increase sociality in comparison to the control group. Ketamine had no effect on time spent in the center during the open field trials, while oxytocin increased overall center time across all groups, suggesting a reduction in anxiety. Amygdala activity was consistent across all drug groups during social and nonsocial behavioral trials. However, oxytocin reduced overall amygdala EEG power during the two behavioral tasks. Alternatively, ketamine did not significantly affect EEG power throughout the tasks. Decreased EEG power in the amygdala, as caused by oxytocin, may be related to both reduced anxiety and increased social behaviors. Data suggest that separate pro-social and social anxiety pathways may mediate social preference. PMID:26214213

  9. Reducing power consumption during execution of an application on a plurality of compute nodes

    DOEpatents

    Archer, Charles J.; Blocksome, Michael A.; Peters, Amanda E.; Ratterman, Joseph D.; Smith, Brian E.

    2012-06-05

    Methods, apparatus, and products are disclosed for reducing power consumption during execution of an application on a plurality of compute nodes that include: executing, by each compute node, an application, the application including power consumption directives corresponding to one or more portions of the application; identifying, by each compute node, the power consumption directives included within the application during execution of the portions of the application corresponding to those identified power consumption directives; and reducing power, by each compute node, to one or more components of that compute node according to the identified power consumption directives during execution of the portions of the application corresponding to those identified power consumption directives.

  10. Low-power SXGA active matrix OLED

    NASA Astrophysics Data System (ADS)

    Wacyk, Ihor; Prache, Olivier; Ghosh, Amal

    2009-05-01

    This paper presents the design and first evaluation of a full-color 1280×3×1024 pixel, active matrix organic light emitting diode (AMOLED) microdisplay that operates at a low power of 200mW under typical operating conditions of 35fL, and offers a precision 30-bit RGB digital interface in a compact size (0.78-inch diagonal active area). The new system architecture developed by eMagin for the SXGA microdisplay, based on a separate FPGA driver and AMOLED display chip, offers several benefits, including better power efficiency, cost-effectiveness, more features for improved performance, and increased system flexibility.

  11. The Role of Nuclear Power in Reducing Greenhouse Gas Emissions

    EPA Science Inventory

    For Frank Princiotta’s book, Global Climate Change—The Technology Challenge As this chapter will point out, nuclear energy is a low greenhouse gas emitter and is capable of providing large amounts of power using proven technology. In the immediate future, it can contribute to gr...

  12. Innovative Technology Reduces Power Plant Emissions - Commercialization Success

    NASA Technical Reports Server (NTRS)

    Parrish, Clyde

    2004-01-01

    Emission control system development includes: (1) Development of new oxidizer scrubber system to eliminate NOx waste and produce fertilizer (2) Technology licensed and a 1 to 3 MWatt-scale prototype installed on. power plant (3) Development of method to oxidize NO. to N02 (4) Experience gained from licensing NASA technology

  13. Innovative Technology Reduces Power Plant Emissions-Commercialization Success

    NASA Technical Reports Server (NTRS)

    Parrish, Clyde; Chung, Landy

    2004-01-01

    Overview of emission control system development: (1) Development of new oxidizer scrubber system to eliminate NOx waste and produce fertilizer (2) Technology licensed and a 1 to 3 MWatt-scale prototype installed on power plant (3) Development of method to oxidize NO to NO2 (4) Experience gained from licensing NASA technology.

  14. Recreational Activities to Reduce Behavioural Symptoms in Dementia

    PubMed Central

    Kolanowski, Ann; Fick, Donna M.; Buettner, Linda

    2009-01-01

    Few clinicians have an educational grounding in the use of nonpharmacological therapies for people with dementia. In this article, we explore the utility of recreational activities as one nonpharmacological intervention that has demonstrated effectiveness for reducing the behavioural symptoms of dementia. The implementation of effective recreational activities involves three components: understanding the evidence for this approach; acknowledging the need to reduce medications that have the potential to interfere with activity effectiveness; and individualizing activities so that the maximum benefit from the intervention is obtained. PMID:20046903

  15. Systematic review of active workplace interventions to reduce sickness absence

    PubMed Central

    2013-01-01

    Background The workplace is used as a setting for interventions to prevent and reduce sickness absence, regardless of the specific medical conditions and diagnoses. Aims To give an overview of the general effectiveness of active workplace interventions aimed at preventing and reducing sickness absence. Methods We systematically searched PubMed, Embase, Psych-info, and ISI web of knowledge on 27 December 2011. Inclusion criteria were (i) participants over 18 years old with an active role in the intervention, (ii) intervention done partly or fully at the workplace or at the initiative of the workplace and (iii) sickness absence reported. Two reviewers independently screened articles, extracted data and assessed risk of bias. A narrative synthesis was used. Results We identified 2036 articles of which, 93 were assessed in full text. Seventeen articles were included (2 with low and 15 with medium risk of bias), with a total of 24 comparisons. Five interventions from four articles significantly reduced sickness absence. We found moderate evidence that graded activity reduced sickness absence and limited evidence that the Sheerbrooke model (a comprehensive multidisciplinary intervention) and cognitive behavioural therapy (CBT) reduced sickness absence. There was moderate evidence that workplace education and physical exercise did not reduce sickness absence. For other interventions, the evidence was insufficient to draw conclusions. Conclusions The review found limited evidence that active workplace interventions were not generally effective in reducing sickness absence, but there was moderate evidence of effect for graded activity and limited evidence for the effectiveness of the Sheerbrooke model and CBT. PMID:23223750

  16. Reducing the Vulnerability of Electric Power Grids to Terrorist Attacks

    SciTech Connect

    Ross Baldick; Thekla Boutsika; Jin Hur; Manho Joung; Yin Wu; Minqi Zhong

    2009-01-31

    This report describes the development of a cascading outage analyzer that, given an initial disturbance on an electric power system, checks for thermal overloads, under-frequency and over-frequency conditions, and under-voltage conditions that would result in removal of elements from the system. The analyzer simulates the successive tripping of elements due to protective actions until a post-event steady state or a system blackout is reached.

  17. REDUCING POWER PRODUCTION COSTS BY UTILIZING PETROLEUM COKE

    SciTech Connect

    Kevin C. Galbreath; Donald L. Toman; Christopher J. Zygarlicke

    1999-09-01

    Petroleum coke, a byproduct of the petroleum-refining process, is an attractive primary or supplemental fuel for power production primarily because of a progressive and predictable increase in the production volumes of petroleum coke (1, 2). Petroleum coke is most commonly blended with coal in proportions suitable to meet sulfur emission compliance. Petroleum coke is generally less reactive than coal; therefore, the cofiring of petroleum coke with coal typically improves ignition, flame stability, and carbon loss relative to the combustion of petroleum coke alone. Although petroleum coke is a desirable fuel for producing relatively inexpensive electrical power, concerns about the effects of petroleum coke blending on combustion and pollution control processes exist in the coal-fired utility industry (3). The Energy & Environmental Research Center (EERC) completed a 2-year technical assessment of petroleum coke as a supplemental fuel. A survey questionnaire was sent to seven electric utility companies that are currently cofiring coal and petroleum coke in an effort to solicit specific suggestions on research needs and fuel selections. An example of the letter and survey questionnaire is presented in Appendix A. Interest was expressed by most utilities in evaluating the effects of petroleum coke blending on grindability, combustion reactivity, fouling, slagging, and fly ash emissions control. Unexpectedly, concern over corrosion was not expressed by the utilities contacted. Although all seven utilities responded to the question, only two utilities, Northern States Power Company (NSP) and Ameren, sent fuels to the EERC for evaluation. Both utilities sent subbituminous coals from the Power River Basin and petroleum shot coke samples. Petroleum shot coke is produced unintentionally during operational upsets in the petroleum refining process. This report evaluates the effects of petroleum shot coke blending on grindability, fuel reactivity, fouling/slagging, and

  18. Reducing the cognitive workload: Trouble managing power systems

    NASA Technical Reports Server (NTRS)

    Manner, David B.; Liberman, Eugene M.; Dolce, James L.; Mellor, Pamela A.

    1993-01-01

    The complexity of space-based systems makes monitoring them and diagnosing their faults taxing for human beings. Mission control operators are well-trained experts but they can not afford to have their attention diverted by extraneous information. During normal operating conditions monitoring the status of the components of a complex system alone is a big task. When a problem arises, immediate attention and quick resolution is mandatory. To aid humans in these endeavors we have developed an automated advisory system. Our advisory expert system, Trouble, incorporates the knowledge of the power system designers for Space Station Freedom. Trouble is designed to be a ground-based advisor for the mission controllers in the Control Center Complex at Johnson Space Center (JSC). It has been developed at NASA Lewis Research Center (LeRC) and tested in conjunction with prototype flight hardware contained in the Power Management and Distribution testbed and the Engineering Support Center, ESC, at LeRC. Our work will culminate with the adoption of these techniques by the mission controllers at JSC. This paper elucidates how we have captured power system failure knowledge, how we have built and tested our expert system, and what we believe are its potential uses.

  19. Infliximab treatment reduces complement activation in patients with rheumatoid arthritis

    PubMed Central

    Familian, A; Voskuyl, A; van Mierlo, G J; Heijst, H; Twisk, J; Dijkmans, B; Hack, C

    2005-01-01

    Background: Tumour necrosis factor (TNF) blocking agents decrease C reactive protein (CRP) levels in rheumatoid arthritis (RA). It has been shown that CRP may contribute to complement activation in RA. Objective: To assess the effect of intravenous infliximab treatment on complement activation, especially that mediated by CRP, in RA. Methods: 35 patients with active RA (28 joint count Disease Activity Score (DAS28) >4.4) were treated with intravenous injections of infliximab (3 mg/kg, at weeks 0, 2, 6, 14, and 22). Clinical response and plasma levels of complement activation products, of CRP and of CRP-complement complexes, which are specific markers for CRP mediated complement activation, were assessed at the indicated time points up to 22 weeks. The relationship between CRP and CRP-complement complexes was analysed by paired t test between two time points and by generalised estimated equation, to test differences of variables over time. Results: At 2 weeks after the first dose, infliximab significantly reduced overall C3 and C4 activation and plasma levels of CRP and CRP-complement complexes were also significantly reduced at this time point. The effects of infliximab on CRP and complement continued throughout the observation period and were more pronounced in patients with a good response to infliximab treatment. Conclusion: Treatment with infliximab decreases plasma levels of CRP and CRP dependent complement activation products and concomitantly may reduce complement activation in RA. Complement activation may be among the effector mechanisms of TNF in RA. PMID:15958758

  20. Effortful retrieval reduces hippocampal activity and impairs incidental encoding.

    PubMed

    Reas, Emilie T; Brewer, James B

    2013-05-01

    Functional imaging studies frequently report that the hippocampus is engaged by successful episodic memory retrieval. However, considering that concurrent encoding of the background environment occurs during retrieval and influences medial temporal lobe activity, it is plausible that hippocampal encoding functions are reduced with increased attentional engagement during effortful retrieval. Expanding upon evidence that retrieval efforts suppress activity in hippocampal regions implicated in encoding, this study examines the influence of retrieval effort on encoding performance and the interactive effects of encoding and retrieval on hippocampal and neocortical activity. Functional magnetic resonance imaging was conducted while subjects performed a word recognition task with incidental picture encoding. Both lower memory strength and increased search duration were associated with encoding failure and reduced hippocampal and default network activity. Activity in the anterior hippocampus tracked encoding, which was more strongly deactivated when incidental encoding was unsuccessful. These findings highlight potential contributions from background encoding processes to hippocampal activations during neuroimaging studies of episodic memory retrieval. PMID:23378272

  1. Reducing muscle effort in walking through powered exoskeletons.

    PubMed

    Lenzi, T; Zanotto, D; Stegall, P; Carrozza, M C; Agrawal, S K

    2012-01-01

    This paper presents a novel assistive control for lower limb exoskeletons. The controller provides the user with a scaled version of the Winter's nominal torque profile, which is adapted online to the specific gait features of the user. The proposed assistive controller is implemented on the ALEX II exoskeleton and tested on two healthy subjects. Experimental results show that when assisted by the exoskeleton users can reduce the muscle effort compared to free walking. PMID:23366786

  2. Methods of reducing wind power changes from large turbine arrays

    SciTech Connect

    Schlueter, R.; Dorsey, J.; Lotfalian, M.; Park, G.; Shayanfar, M.

    1983-06-01

    This paper discusses methods of reducing the WECS generation change through selection of the wind turbine model for each site, selection of an appropriate siting configuration, and wind array controls. An analysis of wind generation change from an echelon and a farm for passage of a thunderstorm is presented to establish the factors concerning the wind turbine model and siting configuration that contribute to these variations. Detailed simulation results indicate more precisely how these factors can be exploited to minimize the WECS generation changes observed. Reduction of the wind generation change over ten minutes is shown to reduce the increase in spinning reserve, unloadable generation and load following requirements on unit commitment when significant WECS generation is present and the farm penetration constraint is satisfied. Controls on the blade pitch angle of all wind turbines in an array or a battery control are shown to reduce both the wind generation change out of an array and the effective farm penetration in anticipation of a storm so that the farm penetration constraint may be satisfied.

  3. Active micromachines: Microfluidics powered by mesoscale turbulence

    PubMed Central

    Thampi, Sumesh P.; Doostmohammadi, Amin; Shendruk, Tyler N.; Golestanian, Ramin; Yeomans, Julia M.

    2016-01-01

    Dense active matter, from bacterial suspensions and microtubule bundles driven by motor proteins to cellular monolayers and synthetic Janus particles, is characterized by mesoscale turbulence, which is the emergence of chaotic flow structures. By immersing an ordered array of symmetric rotors in an active fluid, we introduce a microfluidic system that exploits spontaneous symmetry breaking in mesoscale turbulence to generate work. The lattice of rotors self-organizes into a spin state where neighboring discs continuously rotate in permanent alternating directions due to combined hydrodynamic and elastic effects. Our virtual prototype demonstrates a new research direction for the design of micromachines powered by the nematohydrodynamic properties of active turbulence. PMID:27419229

  4. Active micromachines: Microfluidics powered by mesoscale turbulence.

    PubMed

    Thampi, Sumesh P; Doostmohammadi, Amin; Shendruk, Tyler N; Golestanian, Ramin; Yeomans, Julia M

    2016-07-01

    Dense active matter, from bacterial suspensions and microtubule bundles driven by motor proteins to cellular monolayers and synthetic Janus particles, is characterized by mesoscale turbulence, which is the emergence of chaotic flow structures. By immersing an ordered array of symmetric rotors in an active fluid, we introduce a microfluidic system that exploits spontaneous symmetry breaking in mesoscale turbulence to generate work. The lattice of rotors self-organizes into a spin state where neighboring discs continuously rotate in permanent alternating directions due to combined hydrodynamic and elastic effects. Our virtual prototype demonstrates a new research direction for the design of micromachines powered by the nematohydrodynamic properties of active turbulence. PMID:27419229

  5. Potential nanotechnology applications for reducing freshwater consumption at coal fired power plants : an early view.

    SciTech Connect

    Elcock, D.

    2010-09-17

    , would reduce energy use and concomitant water consumption. These inefficiencies include air heater inefficiencies, boiler corrosion, low operating temperatures, fuel inefficiencies, and older components that are subject to strain and failure. A variety of nanotechnology applications that could potentially be used to reduce the amount of freshwater consumed - either directly or indirectly - by these areas and activities was identified. These applications include membranes that use nanotechnology or contain nanomaterials for improved water purification and carbon capture; nano-based coatings and lubricants to insulate and reduce heat loss, inhibit corrosion, and improve fuel efficiency; nano-based catalysts and enzymes that improve fuel efficiency and improve sulfur removal efficiency; nanomaterials that can withstand high temperatures; nanofluids that have better heat transfer characteristics than water; nanosensors that can help identify strain and impact damage, detect and monitor water quality parameters, and measure mercury in flue gas; and batteries and capacitors that use nanotechnology to enable utility-scale storage. Most of these potential applications are in the research stage, and few have been deployed at coal-fired power plants. Moving from research to deployment in today's economic environment will be facilitated with federal support. Additional support for research development and deployment (RD&D) for some subset of these applications could lead to reductions in water consumption and could provide lessons learned that could be applied to future efforts. To take advantage of this situation, it is recommended that NETL pursue funding for further research, development, or deployment for one or more of the potential applications identified in this report.

  6. Sox11 Reduces Caspase-6 Cleavage and Activity

    PubMed Central

    Waldron-Roby, Elaine; Hoerauf, Janine; Arbez, Nicolas; Zhu, Shanshan; Kulcsar, Kirsten; Ross, Christopher A.

    2015-01-01

    The apoptotic cascade is an orchestrated event, whose final stages are mediated by effector caspases. Regulatory binding proteins have been identified for caspases such as caspase-3, -7, -8, and -9. Many of these proteins belong to the inhibitor of apoptosis (IAP) family. By contrast, caspase-6 is not believed to be influenced by IAPs, and little is known about its regulation. We therefore performed a yeast-two-hybrid screen using a constitutively inactive form of caspase-6 for bait in order to identify novel regulators of caspase-6 activity. Sox11 was identified as a potential caspase-6 interacting protein. Sox11 was capable of dramatically reducing caspase-6 activity, as well as preventing caspase-6 self- cleavage. Several regions, including amino acids 117–214 and 362–395 within sox11 as well as a nuclear localization signal (NLS) all contributed to the reduction in caspase-6 activity. Furthermore, sox11 was also capable of decreasing other effector caspase activity but not initiator caspases -8 and -9. The ability of sox11 to reduce effector caspase activity was also reflected in its capacity to reduce cell death following toxic insult. Interestingly, other sox proteins also had the ability to reduce caspase-6 activity but to a lesser extent than sox11. PMID:26505998

  7. Reducing health care's carbon footprint--the power of nursing.

    PubMed

    Muñoz, Aliria

    2012-11-01

    Global warming and environmentalism continue to be national and international issues as their complexities and implications become better understood. One ironic contributor to the degradation of the environment is the health care system. Serving as clinical laboratories, hotels, restaurants, and offices that never close, U.S. hospitals produce more than 2 million tons of waste annually. Although the consequences and significance of health care's carbon footprint are undeniable, strategies to reduce this impact are challenging. This article discusses how the role, traits, and knowledge of nurses combined with their positions in the health care system make them key players in creating an environmentally sustainable health care industry. With an analysis of environmental action versus inaction, this article explores how nurses at the forefront of health care are equipped to change practice that will reach far beyond the bedside. PMID:23413481

  8. Reduced Chitinase Activities in Ant Plants of the Genus Macaranga

    NASA Astrophysics Data System (ADS)

    Heil, Martin; Fiala, Brigitte; Linsenmair, K. Eduard; Boller, Thomas

    Many plant species have evolved mutualistic associations with ants, protecting their host against detrimental influences such as herbivorous insects. Letourneau (1998) reported in the case of Piper that ants defend their plants principally against stem-boring insects and also reduce fungal infections on inflorescences. Macaranga plants that were experimentally deprived of their symbiotic Crematogaster ants suffered heavily from shoot borers and pathogenic fungi (Heil 1998). Here we report that ants seem to reduce fungal infections actively in the obligate myrmecophyte Macarangatriloba (Euphorbiaceae), while ant-free plants can be easily infected. We also found extremely low chitinase activity in Macaranga plants. The plants' own biochemical defense seems to be reduced, and low chitinase activity perhaps may represent a predisposition for the evolution of myrmecophytism. These plants are therefore highly dependent on their ants, which obviously function not only as an antiherbivore defense but also as an effective agent against fungal pathogens.

  9. Reducing power production costs by utilizing petroleum coke. Annual report

    SciTech Connect

    Galbreath, K.C.

    1998-07-01

    A Powder River Basin subbituminous coal from the North Antelope mine and a petroleum shot coke were received from Northern States Power Company (NSP) for testing the effects of parent fuel properties on coal-coke blend grindability and evaluating the utility of petroleum coke blending as a strategy for improving electrostatic precipitator (ESP) particulate collection efficiency. Petroleum cokes are generally harder than coals, as indicated by Hardgrove grindability tests. Therefore, the weaker coal component may concentrate in the finer size fractions during the pulverizing of coal-coke blends. The possibility of a coal-coke size fractionation effect is being investigated because it may adversely affect combustion performance, it may enhance ESP particulate collection efficiency. Petroleum cokes contain much higher concentrations of V relative to coals. Consequently, coke blending can significantly increase the V content of fly ash resulting from coal-coke combustion. Pentavalent vanadium oxide (V{sub 2}O{sub 5}) is a known catalyst for transforming gaseous sulfur dioxide (SO{sub 2}[g]) to gaseous sulfur trioxide (SO{sub 3}[g]). The presence of SO{sub 3}(g) strongly affects fly ash resistivity and, thus, ESP performance.

  10. REDUCING POWER PRODUCTION COSTS BY UTILIZING PETROLEUM COKE

    SciTech Connect

    1998-09-01

    A Powder River Basin subbituminous coal from the North Antelope mine and a petroleum shot coke were received from Northern States Power Company (NSP) for testing the effects of parent fuel properties on coal-coke blend grindability and evaluating the utility of petroleum coke blending as a strategy for improving electrostatic precipitator (ESP) particulate collection efficiency. Petroleum cokes are generally harder than coals, as indicated by Hardgrove grindability tests. Therefore, the weaker coal component may concentrate in the finer size fractions during the pulverizing of coal-coke blends. The possibility of a coal-coke size fractionation effect is being investigated because it may adversely affect combustion performance. Although the blending of petroleum coke with coal may adversely affect combustion performance, it may enhance ESP particulate collection efficiency. Petroleum cokes contain much higher concentrations of V relative to coals. Consequently, coke blending can significantly increase the V content of fly ash resulting from coal-coke combustion. Pentavalent vanadium oxide (V{sub 2}O{sub 5}) is a known catalyst for transforming gaseous sulfur dioxide (SO{sub 2}[g]) to gaseous sulfur trioxide (SO{sub 3}[g]). The presence of SO{sub 3}(g) strongly affects fly ash resistivity and, thus, ESP performance.

  11. Reduced power processor requirements for the 30-cm diameter Hg ion thruster

    NASA Technical Reports Server (NTRS)

    Rawlin, V. K.

    1979-01-01

    An evaluation of simplifications for the thruster power processor interface for a 30 cm Hg ion thruster is presented. Tests on the engine, thruster control, and the power supplies are performed. Reduced power processors requirements are defined and the impact on thruster design, performance, and lifetime are assessed.

  12. Monitoring Biological Activity at Geothermal Power Plants

    SciTech Connect

    Peter Pryfogle

    2005-09-01

    The economic impact of microbial growth in geothermal power plants has been estimated to be as high as $500,000 annually for a 100 MWe plant. Many methods are available to monitor biological activity at these facilities; however, very few plants have any on-line monitoring program in place. Metal coupon, selective culturing (MPN), total organic carbon (TOC), adenosine triphosphate (ATP), respirometry, phospholipid fatty acid (PLFA), and denaturing gradient gel electrophoresis (DGGE) characterizations have been conducted using water samples collected from geothermal plants located in California and Utah. In addition, the on-line performance of a commercial electrochemical monitor, the BIoGEORGE?, has been evaluated during extended deployments at geothermal facilities. This report provides a review of these techniques, presents data on their application from laboratory and field studies, and discusses their value in characterizing and monitoring biological activities at geothermal power plants.

  13. Statistical Performances of Resistive Active Power Splitter

    NASA Astrophysics Data System (ADS)

    Lalléchère, Sébastien; Ravelo, Blaise; Thakur, Atul

    2016-03-01

    In this paper, the synthesis and sensitivity analysis of an active power splitter (PWS) is proposed. It is based on the active cell composed of a Field Effect Transistor in cascade with shunted resistor at the input and the output (resistive amplifier topology). The PWS uncertainty versus resistance tolerances is suggested by using stochastic method. Furthermore, with the proposed topology, we can control easily the device gain while varying a resistance. This provides useful tool to analyse the statistical sensitivity of the system in uncertain environment.

  14. Reduced respiratory neural activity elicits phrenic motor facilitation.

    PubMed

    Mahamed, Safraaz; Strey, Kristi A; Mitchell, Gordon S; Baker-Herman, Tracy L

    2011-03-15

    We hypothesized that reduced respiratory neural activity elicits compensatory mechanisms of plasticity that enhance respiratory motor output. In urethane-anesthetized and ventilated rats, we reversibly reduced respiratory neural activity for 25-30 min using: hypocapnia (end tidal CO(2)=30 mmHg), isoflurane (~1%) or high frequency ventilation (HFV; ~100 breaths/min). In all cases, increased phrenic burst amplitude was observed following restoration of respiratory neural activity (hypocapnia: 92±22%; isoflurane: 65±22%; HFV: 54±13% baseline), which was significantly greater than time controls receiving the same surgery, but no interruptions in respiratory neural activity (3±5% baseline, p<0.05). Hypocapnia also elicited transient increases in respiratory burst frequency (9±2 versus 1±1bursts/min, p<0.05). Our results suggest that reduced respiratory neural activity elicits a unique form of plasticity in respiratory motor control which we refer to as inactivity-induced phrenic motor facilitation (iPMF). iPMF may prevent catastrophic decreases in respiratory motor output during ventilatory control disorders associated with abnormal respiratory activity. PMID:21167322

  15. Reduced respiratory neural activity elicits phrenic motor facilitation

    PubMed Central

    Mahamed, Safraaz; Strey, Kristi A.; Mitchell, Gordon S.; Baker-Herman, Tracy L.

    2011-01-01

    We hypothesized that reduced respiratory neural activity elicits compensatory mechanisms of plasticity that enhance respiratory motor output. In urethane-anesthetized and ventilated rats, we reversibly reduced respiratory neural activity for 25–30 min using: hypocapnia (end tidal CO2 = 30 mmHg), isoflurane (~ 1%) or high frequency ventilation (HFV; ~100 breaths/min). In all cases, increased phrenic burst amplitude was observed following restoration of respiratory neural activity (hypocapnia: 92 ± 22%; isoflurane: 65 ± 22%; HFV: 54 ± 13% baseline), which was significantly greater than time controls receiving the same surgery, but no interruptions in respiratory neural activity (3 ± 5% baseline, p<0.05). Hypocapnia also elicited transient increases in respiratory burst frequency (9 ± 2 versus 1 ± 1 bursts/min, p<0.05). Our results suggest that reduced respiratory neural activity elicits a unique form of plasticity in respiratory motor control which we refer to as inactivity-induced phrenic motor facilitation (iPMF). iPMF may prevent catastrophic decreases in respiratory motor output during ventilatory control disorders associated with abnormal respiratory activity. PMID:21167322

  16. Ratchet transport powered by chiral active particles

    PubMed Central

    Ai, Bao-quan

    2016-01-01

    We numerically investigate the ratchet transport of mixtures of active and passive particles in a transversal asymmetric channel. A big passive particle is immersed in a ‘sea’ of active particles. Due to the chirality of active particles, the longitudinal directed transport is induced by the transversal asymmetry. For the active particles, the chirality completely determines the direction of the ratchet transport, the counterclockwise and clockwise particles move to the opposite directions and can be separated. However, for the passive particle, the transport behavior becomes complicated, the direction is determined by competitions among the chirality, the self-propulsion speed, and the packing fraction. Interestingly, within certain parameters, the passive particle moves to the left, while active particles move to the right. In addition, there exist optimal parameters (the chirality, the height of the barrier, the self-propulsion speed and the packing fraction) at which the rectified efficiency takes its maximal value. Our findings could be used for the experimental pursuit of the ratchet transport powered by chiral active particles. PMID:26795952

  17. Ratchet transport powered by chiral active particles

    NASA Astrophysics Data System (ADS)

    Ai, Bao-Quan

    2016-01-01

    We numerically investigate the ratchet transport of mixtures of active and passive particles in a transversal asymmetric channel. A big passive particle is immersed in a ‘sea’ of active particles. Due to the chirality of active particles, the longitudinal directed transport is induced by the transversal asymmetry. For the active particles, the chirality completely determines the direction of the ratchet transport, the counterclockwise and clockwise particles move to the opposite directions and can be separated. However, for the passive particle, the transport behavior becomes complicated, the direction is determined by competitions among the chirality, the self-propulsion speed, and the packing fraction. Interestingly, within certain parameters, the passive particle moves to the left, while active particles move to the right. In addition, there exist optimal parameters (the chirality, the height of the barrier, the self-propulsion speed and the packing fraction) at which the rectified efficiency takes its maximal value. Our findings could be used for the experimental pursuit of the ratchet transport powered by chiral active particles.

  18. Ratchet transport powered by chiral active particles.

    PubMed

    Ai, Bao-quan

    2016-01-01

    We numerically investigate the ratchet transport of mixtures of active and passive particles in a transversal asymmetric channel. A big passive particle is immersed in a 'sea' of active particles. Due to the chirality of active particles, the longitudinal directed transport is induced by the transversal asymmetry. For the active particles, the chirality completely determines the direction of the ratchet transport, the counterclockwise and clockwise particles move to the opposite directions and can be separated. However, for the passive particle, the transport behavior becomes complicated, the direction is determined by competitions among the chirality, the self-propulsion speed, and the packing fraction. Interestingly, within certain parameters, the passive particle moves to the left, while active particles move to the right. In addition, there exist optimal parameters (the chirality, the height of the barrier, the self-propulsion speed and the packing fraction) at which the rectified efficiency takes its maximal value. Our findings could be used for the experimental pursuit of the ratchet transport powered by chiral active particles. PMID:26795952

  19. Low level laser therapy reduces inflammation in activated Achilles tendinitis

    NASA Astrophysics Data System (ADS)

    Bjordal, Jan M.; Iversen, Vegard; Lopes-Martins, Rodrigo Alvaro B.

    2006-02-01

    Objective: Low level laser therapy (LLLT) has been forwarded as therapy for osteoarthritis and tendinopathy. Results in animal and cell studies suggest that LLLT may act through a biological mechanism of inflammatory modulation. The current study was designed to investigate if LLLT has an anti-inflammatory effect on activated tendinitis of the Achilles tendon. Methods: Seven patients with bilateral Achilles tendonitis (14 tendons) who had aggravated symptoms by pain-inducing activity immediately prior to the study. LLLT (1.8 Joules for each of three points along the Achilles tendon with 904nm infrared laser) and placebo LLLT were administered to either Achilles tendons in a random order to which patients and therapist were blinded. Inflammation was examined by 1) mini-invasive microdialysis for measuring the concentration of inflammatory marker PGE II in the peritendinous tissue, 2) ultrasound with Doppler measurement of peri- and intratendinous blood flow, 3) pressure pain algometry and 4) single hop test. Results: PGE 2- levels were significantly reduced at 75, 90 and 105 minutes after active LLLT compared both to pre-treatment levels (p=0.026) and to placebo LLLT (p=0.009). Changes in pressure pain threshold (PPT) were significantly different (P=0.012) between groups. PPT increased by a mean value of 0.19 kg/cm2 [95%CI:0.04 to 0.34] after treatment in the active LLLT group, while pressure pain threshold was reduced by -0.20 kg/cm2 [95%CI:-0.45 to 0.05] after placebo LLLT. Conclusion: LLLT can be used to reduce inflammatory musculskeletal pain as it reduces inflammation and increases pressure pain threshold levels in activity-induced pain episodes of Achilles tendinopathy.

  20. Energy and power limits for microbial activity

    NASA Astrophysics Data System (ADS)

    LaRowe, D.; Amend, J.

    2014-12-01

    The goal of this presentation is to describe a quantitative framework for determining how energy limits microbial activity, biomass and, ultimately, biogeochemical processes. Although this model can be applied to any environment, its utility is demonstrated in marine sediments, which are an attractive test habitat because they encompass a broad spectrum of energy levels, varying amounts of biomass and are ubiquitous. The potential number of active microbial cells in Arkonas Basin (Baltic Sea) sediments are estimated as a function of depth by quantifying the amount of energy that is available to them and the rate at which it is supplied: power. The amount of power supplied per cubic centimeter of sediment is determined by calculating the Gibbs energy of fermentation and sulfate reduction in combination with the rate of particulate organic carbon, POC, degradation. The Reactive Continuum Model (Boudreau and Ruddick, 1991), RCM, is used to determine the rate at which POC is made available for microbial consumption. The RCM represents POC as containing a range of different types of organic compounds whose ability to be consumed by microorganisms varies as a function of the age of the sediment and on the distribution of compound types that were initially deposited. The sediment age model and RCM parameters determined by (Mogollon et al., 2012) are used. The power available for fermentation and sulfate reduction coupled to H2 and acetate oxidation varies from 10-8 W cm-3 at the sediment water interface to between 10-11 - 10-12 W cm-3 at 3.5 meters below the seafloor, mbsf. Using values of maintenance powers for each of these catabolic activities taken from the literature, the total number of active cells in these sediments similarly decreases from just less than 108 cell cm-3 at the SWI to 4.6 x 104 cells cm-3 at 3.5 mbsf. The number of moles of POC decreases from 2.6 x 10-5 to 9.5 x 10-6, also becoming more recalcitrant with depth. Boudreau, B. P. and Ruddick, B. R

  1. Reducing water freshwater consumption at coal-fired power plants : approaches used outside the United States.

    SciTech Connect

    Elcock, D.

    2011-05-09

    Coal-fired power plants consume huge quantities of water, and in some water-stressed areas, power plants compete with other users for limited supplies. Extensive use of coal to generate electricity is projected to continue for many years. Faced with increasing power demands and questionable future supplies, industries and governments are seeking ways to reduce freshwater consumption at coal-fired power plants. As the United States investigates various freshwater savings approaches (e.g., the use of alternative water sources), other countries are also researching and implementing approaches to address similar - and in many cases, more challenging - water supply and demand issues. Information about these non-U.S. approaches can be used to help direct near- and mid-term water-consumption research and development (R&D) activities in the United States. This report summarizes the research, development, and deployment (RD&D) status of several approaches used for reducing freshwater consumption by coal-fired power plants in other countries, many of which could be applied, or applied more aggressively, at coal-fired power plants in the United States. Information contained in this report is derived from literature and Internet searches, in some cases supplemented by communication with the researchers, authors, or equipment providers. Because there are few technical, peer-reviewed articles on this topic, much of the information in this report comes from the trade press and other non-peer-reviewed references. Reducing freshwater consumption at coal-fired power plants can occur directly or indirectly. Direct approaches are aimed specifically at reducing water consumption, and they include dry cooling, dry bottom ash handling, low-water-consuming emissions-control technologies, water metering and monitoring, reclaiming water from in-plant operations (e.g., recovery of cooling tower water for boiler makeup water, reclaiming water from flue gas desulfurization [FGD] systems), and

  2. Recent approaches for reducing hemolytic activity of chemotherapeutic agents.

    PubMed

    Jeswani, Gunjan; Alexander, Amit; Saraf, Shailendra; Saraf, Swarnlata; Qureshi, Azra; Ajazuddin

    2015-08-10

    Drug induced hemolysis is a frequent complication associated with chemotherapy. It results from interaction of drug with erythrocyte membrane and leads to cell lysis. In recent past, various approaches were made to reduce drug-induced hemolysis, which includes drug polymer conjugation, drug delivery via colloidal carriers and hydrogels, co-administration of botanical agents and modification in molecular chemistry of drug molecules. The basic concept behind these strategies is to protect the red blood cells from membrane damaging effects of drugs. There are several examples of drug polymer conjugate that either are approved by Food and Drug Administration or are under clinical trial for delivering drugs with reduced toxicities. Likewise, colloidal carriers are also used successfully nowadays for the delivery of various chemotherapeutic agents like gemcitabine and amphotericin B with remarkable decrease in their hemolytic activity. Similarly, co-administration of botanical agents with drugs works as secondary system proving protection and strength to erythrocyte membranes. In addition to the above statement, interaction hindrance between RBC and drug molecule by molecular modification plays an important role in reducing hemolysis. This review predominantly describes the above recent approaches explored to achieve the reduced hemolytic activity of drugs especially chemotherapeutic agents. PMID:26047758

  3. Low-chromium reduced-activation ferritic steels for fusion

    SciTech Connect

    Klueh, R.L.; Alexander, D.J.; Kenik, E.A.

    1996-04-01

    Development of reduced-activation ferritic steels has concentrated on high-chromium (8-10 wt% Cr) steels. However, there are advantages for a low-chromium steel, and initial ORNL studies on reduced-activation steels were on compositions with 2.25 to 12% Cr. Those studies showed an Fe-2.25Cr-2W-0.25V-0.1C (2 1/4Cr-2WV) steel to have the highest strenglth of the steels studied. Although this steel had the best strength, Charpy impact properties were inferior to those of an Fe-9Cr-2W-0.25V-0.07Ta-0.1C (9Cr-2WVTa) and an Fe-2.25Cr-2W-0.1C (2 1/4Cr-2W) steel. Therefore, further development of the low-chromium Cr-W steels was required. These results indicate that it is possible to develop low-chromium reduced-activation ferritic steels that have tensile and impact properties as good or better than those of high-chromium (7-9% Cr) steels. Further improvement of properties should be possible by optimizing the composition.

  4. Knee loading reduces MMP13 activity in the mouse cartilage

    PubMed Central

    2013-01-01

    Background Moderate loads with knee loading enhance bone formation, but its effects on the maintenance of the knee are not well understood. In this study, we examined the effects of knee loading on the activity of matrix metalloproteinase13 (MMP13) and evaluated the role of p38 MAPK and Rac1 GTPase in the regulation of MMP13. Methods Knee loading (0.5–3 N for 5 min) was applied to the right knee of surgically-induced osteoarthritis (OA) mice as well as normal (non-OA) mice, and MMP13 activity in the femoral cartilage was examined. The sham-loaded knee was used as a non-loading control. We also employed primary non-OA and OA human chondrocytes as well as C28/I2 chondrocyte cells, and examined MMP13 activity and molecular signaling in response to shear at 2–20 dyn/cm2. Results Daily knee loading at 1 N for 2 weeks suppressed cartilage destruction in the knee of OA mice. Induction of OA elevated MMP13 activity and knee loading at 1 N suppressed this elevation. MMP13 activity was also increased in primary OA chondrocytes, and this increase was attenuated by applying shear at 10 dyn/cm2. Load-driven reduction in MMP13 was associated with a decrease in the phosphorylation level of p38 MAPK (p-p38) and NFκB (p-NFκB). Molecular imaging using a fluorescence resonance energy transfer (FRET) technique showed that Rac1 activity was reduced by shear at 10 dyn/cm2 and elevated by it at 20 dyn/cm2. Silencing Rac1 GTPase significantly reduced MMP13 expression and p-p38 but not p-NFκB. Transfection of a constitutively active Rac1 GTPase mutant increased MMP13 activity, while a dominant negative mutant decreased it. Conclusions Knee loading reduces MMP13 activity at least in part through Rac1-mediated p38 MAPK signaling. This study suggests the possibility of knee loading as a therapy not only for strengthening bone but also preventing tissue degradation of the femoral cartilage. PMID:24180431

  5. Power Line Damage, Electrical Outages Reduced in the ''Sleet Belt'': NICE3 Steel Project Fact Sheet

    SciTech Connect

    2000-04-25

    The AR Windamper System was developed through a grant from the Inventions and Innovation Program, to protect power transmission lines in sleet belt states and provinces by eliminating the ''galloping'' phenomenon. Wind damping products minimize power outages and reduce repair costs to transmission lines.

  6. Blockade of Mast Cell Activation Reduces Cutaneous Scar Formation

    PubMed Central

    Ranzer, Matthew J.; Wilgus, Traci A.; DiPietro, Luisa A.

    2014-01-01

    Damage to the skin initiates a cascade of well-orchestrated events that ultimately leads to repair of the wound. The inflammatory response is key to wound healing both through preventing infection and stimulating proliferation and remodeling of the skin. Mast cells within the tissue are one of the first immune cells to respond to trauma, and upon activation they release pro-inflammatory molecules to initiate recruitment of leukocytes and promote a vascular response in the tissue. Additionally, mast cells stimulate collagen synthesis by dermal fibroblasts, suggesting they may also influence scar formation. To examine the contribution of mast cells in tissue repair, we determined the effects the mast cell inhibitor, disodium cromoglycate (DSCG), on several parameters of dermal repair including, inflammation, re-epithelialization, collagen fiber organization, collagen ultrastructure, scar width and wound breaking strength. Mice treated with DSCG had significantly reduced levels of the inflammatory cytokines IL-1α, IL-1β, and CXCL1. Although DSCG treatment reduced the production of inflammatory mediators, the rate of re-epithelialization was not affected. Compared to control, inhibition of mast cell activity caused a significant decrease in scar width along with accelerated collagen re-organization. Despite the reduced scar width, DSCG treatment did not affect the breaking strength of the healed tissue. Tryptase β1 exclusively produced by mast cells was found to increase significantly in the course of wound healing. However, DSCG treatment did not change its level in the wounds. These results indicate that blockade of mast cell activation reduces scar formation and inflammation without further weakening the healed wound. PMID:24465509

  7. Blockade of mast cell activation reduces cutaneous scar formation.

    PubMed

    Chen, Lin; Schrementi, Megan E; Ranzer, Matthew J; Wilgus, Traci A; DiPietro, Luisa A

    2014-01-01

    Damage to the skin initiates a cascade of well-orchestrated events that ultimately leads to repair of the wound. The inflammatory response is key to wound healing both through preventing infection and stimulating proliferation and remodeling of the skin. Mast cells within the tissue are one of the first immune cells to respond to trauma, and upon activation they release pro-inflammatory molecules to initiate recruitment of leukocytes and promote a vascular response in the tissue. Additionally, mast cells stimulate collagen synthesis by dermal fibroblasts, suggesting they may also influence scar formation. To examine the contribution of mast cells in tissue repair, we determined the effects the mast cell inhibitor, disodium cromoglycate (DSCG), on several parameters of dermal repair including, inflammation, re-epithelialization, collagen fiber organization, collagen ultrastructure, scar width and wound breaking strength. Mice treated with DSCG had significantly reduced levels of the inflammatory cytokines IL-1α, IL-1β, and CXCL1. Although DSCG treatment reduced the production of inflammatory mediators, the rate of re-epithelialization was not affected. Compared to control, inhibition of mast cell activity caused a significant decrease in scar width along with accelerated collagen re-organization. Despite the reduced scar width, DSCG treatment did not affect the breaking strength of the healed tissue. Tryptase β1 exclusively produced by mast cells was found to increase significantly in the course of wound healing. However, DSCG treatment did not change its level in the wounds. These results indicate that blockade of mast cell activation reduces scar formation and inflammation without further weakening the healed wound. PMID:24465509

  8. Strategies to reduce dendritic cell activation through functional biomaterial design

    PubMed Central

    Hume, Patrick S.; He, Jing; Haskins, Kathryn; Anseth, Kristi S.

    2012-01-01

    Dendritic cells play a key role in determining adaptive immunity, and there is growing interest in characterizing and manipulating the interactions between dendritic cells and biomaterial surfaces. Contact with several common biomaterials can induce the maturation of immature dendritic cells, but substrates that reduce dendritic cell maturation are of particular interest within the field of cell-based therapeutics where the goal is to reduce the immune response to cell-laden material carriers. In this study, we use a materials-based strategy to functionalize poly(ethylene glycol) hydrogels with immobilized immunosuppressive factors (TGF-β1 and IL-10) to reduce the maturation of immature dendritic cells. TGF-β1 and IL-10 are commonly employed as soluble factors to program dendritic cells in vitro, and we demonstrate that these proteins retain bioactivity towards dendritic cells when immobilized on hydrogel surfaces. Following stimulation with lipopolysaccharide (LPS) and/or cytokines, a dendritic cell line interacting with the surfaces of immunosuppressive hydrogels expressed reduced markers of maturation, including IL-12 and MHCII. The bioactivity of these immunomodulatory hydrogels was further confirmed with primary bone marrow dendritic cells (BMDCs) isolated from non-obese diabetic (NOD) mice, as quantified by a decrease in activation markers and a significantly reduced capacity to activate T cells. Furthermore, by introducing a second signal to promote BMDC-material interactions combined with the presentation of tolerizing signals, the mulitfunctional PEG hydrogels were found to further increase signaling towards BMDCs, as evidenced by greater reductions in maturation markers. PMID:22361099

  9. Large roads reduce bat activity across multiple species.

    PubMed

    Kitzes, Justin; Merenlender, Adina

    2014-01-01

    Although the negative impacts of roads on many terrestrial vertebrate and bird populations are well documented, there have been few studies of the road ecology of bats. To examine the effects of large roads on bat populations, we used acoustic recorders to survey bat activity along ten 300 m transects bordering three large highways in northern California, applying a newly developed statistical classifier to identify recorded calls to the species level. Nightly counts of bat passes were analyzed with generalized linear mixed models to determine the relationship between bat activity and distance from a road. Total bat activity recorded at points adjacent to roads was found to be approximately one-half the level observed at 300 m. Statistically significant road effects were also found for the Brazilian free-tailed bat (Tadarida brasiliensis), big brown bat (Eptesicus fuscus), hoary bat (Lasiurus cinereus), and silver-haired bat (Lasionycteris noctivagans). The road effect was found to be temperature dependent, with hot days both increasing total activity at night and reducing the difference between activity levels near and far from roads. These results suggest that the environmental impacts of road construction may include degradation of bat habitat and that mitigation activities for this habitat loss may be necessary to protect bat populations. PMID:24823689

  10. Conformational Preferences Underlying Reduced Activity of a Thermophilic Ribonuclease H

    PubMed Central

    Stafford, Kate A.; Trbovic, Nikola; Butterwick, Joel A.; Abel, Robert; Friesner, Richard A.; Palmer, Arthur G.

    2015-01-01

    The conformational basis for reduced activity of the thermophilic ribonuclease HI enzyme from Thermus thermophilus, compared to its mesophilic homolog from Escherichia coli, is elucidated using a combination of NMR spectroscopy and molecular dynamics (MD) simulations. Explicit-solvent all-atom MD simulations of the two wild-type proteins and an E. coli mutant in which a glycine residue is inserted after position 80 to mimic the T. thermophilus protein reproduce the differences in conformational dynamics determined from 15N spin-relaxation NMR spectroscopy of three loop regions that surround the active site and contain functionally important residues: the glycine-rich region, the handle region, and the β5/αE loop. Examination of the MD trajectories indicates that the thermophilic protein samples conformations productive for substrate binding and activity less frequently than the mesophilic enzyme, although these differences may manifest as either increased or decreased relative flexibility of the different regions. Additional MD simulations indicate that mutations increasing activity of the T. thermophilus enzyme at mesophilic temperatures do so by reconfiguring the local environments of the mutated sites to more closely resemble active conformations. Taken together, the results show that both locally increased and decreased flexibility contribute to an overall reduction in activity of T. thermophilus ribonuclease H compared to its mesophilic E. coli homolog. PMID:25550198

  11. Large Roads Reduce Bat Activity across Multiple Species

    PubMed Central

    Kitzes, Justin; Merenlender, Adina

    2014-01-01

    Although the negative impacts of roads on many terrestrial vertebrate and bird populations are well documented, there have been few studies of the road ecology of bats. To examine the effects of large roads on bat populations, we used acoustic recorders to survey bat activity along ten 300 m transects bordering three large highways in northern California, applying a newly developed statistical classifier to identify recorded calls to the species level. Nightly counts of bat passes were analyzed with generalized linear mixed models to determine the relationship between bat activity and distance from a road. Total bat activity recorded at points adjacent to roads was found to be approximately one-half the level observed at 300 m. Statistically significant road effects were also found for the Brazilian free-tailed bat (Tadarida brasiliensis), big brown bat (Eptesicus fuscus), hoary bat (Lasiurus cinereus), and silver-haired bat (Lasionycteris noctivagans). The road effect was found to be temperature dependent, with hot days both increasing total activity at night and reducing the difference between activity levels near and far from roads. These results suggest that the environmental impacts of road construction may include degradation of bat habitat and that mitigation activities for this habitat loss may be necessary to protect bat populations. PMID:24823689

  12. Reducing power consumption while synchronizing a plurality of compute nodes during execution of a parallel application

    DOEpatents

    Archer, Charles J.; Blocksome, Michael A.; Peters, Amanda E.; Ratterman, Joseph D.; Smith, Brian E.

    2012-04-17

    Methods, apparatus, and products are disclosed for reducing power consumption while synchronizing a plurality of compute nodes during execution of a parallel application that include: beginning, by each compute node, performance of a blocking operation specified by the parallel application, each compute node beginning the blocking operation asynchronously with respect to the other compute nodes; reducing, for each compute node, power to one or more hardware components of that compute node in response to that compute node beginning the performance of the blocking operation; and restoring, for each compute node, the power to the hardware components having power reduced in response to all of the compute nodes beginning the performance of the blocking operation.

  13. Reducing power consumption while synchronizing a plurality of compute nodes during execution of a parallel application

    DOEpatents

    Archer, Charles J.; Blocksome, Michael A.; Peters, Amanda A.; Ratterman, Joseph D.; Smith, Brian E.

    2012-01-10

    Methods, apparatus, and products are disclosed for reducing power consumption while synchronizing a plurality of compute nodes during execution of a parallel application that include: beginning, by each compute node, performance of a blocking operation specified by the parallel application, each compute node beginning the blocking operation asynchronously with respect to the other compute nodes; reducing, for each compute node, power to one or more hardware components of that compute node in response to that compute node beginning the performance of the blocking operation; and restoring, for each compute node, the power to the hardware components having power reduced in response to all of the compute nodes beginning the performance of the blocking operation.

  14. Wind Powering America FY07 Activities Summary

    SciTech Connect

    Not Available

    2008-02-01

    The Wind Powering America FY07 Activities Summary reflects the accomplishments of our state wind working groups, our programs at the National Renewable Energy Laboratory, and our partner organizations. The national WPA team remains a leading force for moving wind energy forward in the United States. WPA continues to work with its national, regional, and state partners to communicate the opportunities and benefits of wind energy to a diverse set of stakeholders. WPA now has 30 state wind working groups (welcoming Georgia and Wisconsin in 2007) that form strategic alliances to communicate wind's benefits to the state stakeholders. More than 140 members of national and state public and private sector organizations from 39 U.S. states and Canada attended the 6th Annual WPA All-States Summit in Los Angeles in June. WPA's emphasis remains on the rural agricultural sector, which stands to reap the significant economic development benefits of wind energy development. Additionally, WPA continues its program of outreach, education, and technical assistance to Native American communities, public power entities, and regulatory and legislative bodies.

  15. Wind Powering America FY06 Activities Summary

    SciTech Connect

    Not Available

    2007-02-01

    The Wind Powering America FY06 Activities Summary reflects the accomplishments of our state wind working groups, our programs at the National Renewable Energy Laboratory, and our partner organizations. The national WPA team remains a leading force for moving wind energy forward in the United States. WPA continues to work with its national, regional, and state partners to communicate the opportunities and benefits of wind energy to a diverse set of stakeholders. WPA now has 29 state wind working groups (welcoming New Jersey, Indiana, Illinois, and Missouri in 2006) that form strategic alliances to communicate wind's benefits to the state stakeholders. More than 120 members of national and state public and private sector organizations from 34 states attended the 5th Annual WPA All-States Summit in Pittsburgh in June.

  16. Reduced brain activation in violent adolescents during response inhibition

    PubMed Central

    Qiao, Yi; Mei, Yi; Du, XiaoXia; Xie, Bin; Shao, Yang

    2016-01-01

    Deficits in inhibitory control have been linked to aggression and violent behaviour. This study aimed to observe whether violent adolescents show different brain activation patterns during response inhibition and to ascertain the roles these brain regions play. A self-report method and modified overt aggression scale (MOAS) were used to evaluate violent behaviour. Functional magnetic resonance imaging was performed in 22 violent adolescents and 17 matched healthy subjects aged 12 to 18 years. While scanning, a go/no-go task was performed. Between-group comparisons revealed that activation in the bilateral middle and superior temporal gyrus, hippocampus, and right orbitofrontal area (BA11) regions were significantly reduced in the violent group compared with the control group. Meanwhile, the violent group had more widespread activation in the prefrontal cortex than that observed in the control group. Activation of the prefrontal cortex in the violent group was widespread but lacking in focus, failing to produce intensive activation in some functionally related regions during response inhibition. PMID:26888566

  17. Optically powered active sensing system for Internet Of Things

    NASA Astrophysics Data System (ADS)

    Gao, Chen; Wang, Jin; Yin, Long; Yang, Jing; Jiang, Jian; Wan, Hongdan

    2014-10-01

    Internet Of Things (IOT) drives a significant increase in the extent and type of sensing technology and equipment. Sensors, instrumentation, control electronics, data logging and transmission units comprising such sensing systems will all require to be powered. Conventionally, electrical powering is supplied by batteries or/and electric power cables. The power supply by batteries usually has a limited lifetime, while the electric power cables are susceptible to electromagnetic interference. In fact, the electromagnetic interference is the key issue limiting the power supply in the strong electromagnetic radiation area and other extreme environments. The novel alternative method of power supply is power over fiber (PoF) technique. As fibers are used as power supply lines instead, the delivery of the power is inherently immune to electromagnetic radiation, and avoids cumbersome shielding of power lines. Such a safer power supply mode would be a promising candidate for applications in IOT. In this work, we built up optically powered active sensing system, supplying uninterrupted power for the remote active sensors and communication modules. Also, we proposed a novel maximum power point tracking technique for photovoltaic power convertors. In our system, the actual output efficiency greater than 40% within 1W laser power. After 1km fiber transmission and opto-electric power conversion, a stable electric power of 210mW was obtained, which is sufficient for operating an active sensing system.

  18. Possible ways of reducing the effect of thermal power facilities on the environment

    NASA Astrophysics Data System (ADS)

    Zroichikov, N. A.; Prokhorov, V. B.; Tupov, V. B.; Arkhipov, A. M.; Fomenko, M. V.

    2015-02-01

    The main trends in the integrated solution of thermal power engineering environmental problems are pointed out taking the Mosenergo power company as an example, and the data are given with respect to the structure of the power engineering equipment of the city of Moscow and its change, energy consumption, and generation of heat and electric energy. The dynamics of atmospheric air pollution of Moscow from 1990 to 2010, as well as the main measures on reducing the adverse effect of the power engineering equipment operation, is given. The results of original designs by the Department of Boiler Installations and Power Engineering Ecology (KU&EE) are given concerning the reduction of nitrogen oxides emissions and the decrease of the noise impact produced by the power engineering equipment.

  19. Reducing the Cost of Energy from Parabolic Trough Solar Power Plants: Preprint

    SciTech Connect

    Price, H.; Kearney, D.

    2003-01-01

    Parabolic trough solar technology is the most proven and lowest cost large-scale solar power technology available today, primarily because of the nine large commercial-scale solar power plants that are operating in the California Mojave Desert. However, no new plants have been built during the past ten years because the cost of power from these plants is more expensive than power from conventional fossil fuel power plants. This paper reviews the current cost of energy and the potential for reducing the cost of energy from parabolic trough solar power plant technology based on the latest technological advancements and projected improvements from industry and sponsored R&D. The paper also looks at the impact of project financing and incentives on the cost of energy.

  20. Designation of alloy composition of reduced-activation martensitic steel

    NASA Astrophysics Data System (ADS)

    Kimura, A.; Kayano, H.; Misawa, T.; Matsui, H.

    1994-09-01

    An alloy composition of reduced-activation martensitic steel for fusion reactor is designed on the basis of the experimental results of postirradiation microstructure, mechanical properties, such as creep, fracture toughness and tensile properties, hydrogen effects and corrosion. At present, a desired composition of the steel is 0.1C-0.05Si-0.5Mn-9Cr-2W-0.25V-0.02Ti-0.05Ta- < 0.002S- < 0.002P by weight percent. Effects of the other minor elements such as Al, Zr and B are also inspected. An addition of 0.05 wt% Ta increases the high temperature strength but reduces the fracture toughness. Susceptibility to hydrogen-induced cracking is reduced by an addition of 0.03 wt% Al, though it results in a severe degradation of the fracture toughness. An addition of 30 wppm B together with the addition of 0.02 wt% Ti increases the fracture toughness. Void nucleation at grain boundaries, however, is enhanced by the B addition under the FFTF irradiation at 638 K in 10 dpa.

  1. Active fans and grizzly bears: Reducing risks for wilderness campers

    NASA Astrophysics Data System (ADS)

    Sakals, M. E.; Wilford, D. J.; Wellwood, D. W.; MacDougall, S. A.

    2010-03-01

    Active geomorphic fans experience debris flows, debris floods and/or floods (hydrogeomorphic processes) that can be hazards to humans. Grizzly bears ( Ursus arctos) can also be a hazard to humans. This paper presents the results of a cross-disciplinary study that analyzed both hydrogeomorphic and grizzly bear hazards to wilderness campers on geomorphic fans along a popular hiking trail in Kluane National Park and Reserve in southwestern Yukon Territory, Canada. Based on the results, a method is proposed to reduce the risks to campers associated with camping on fans. The method includes both landscape and site scales and is based on easily understood and readily available information regarding weather, vegetation, stream bank conditions, and bear ecology and behaviour. Educating wilderness campers and providing a method of decision-making to reduce risk supports Parks Canada's public safety program; a program based on the principle of user self-sufficiency. Reducing grizzly bear-human conflicts complements the efforts of Parks Canada to ensure a healthy grizzly bear population.

  2. Lipoicmethylenedioxyphenol Reduces Experimental Atherosclerosis through Activation of Nrf2 Signaling

    PubMed Central

    Ying, Zhekang; Chen, Minjie; Xie, Xiaoyun; Wang, Xiaoke; Kherada, Nisharahmed; Desikan, Rajagopal; Mihai, Georgeta; Burns, Patrick; Sun, Qinghua; Rajagopalan, Sanjay

    2016-01-01

    Objective Oxidative stress is implicated in the pathogenesis of atherosclerosis, and Nrf2 is the transcriptional factor central in cellular antioxidant responses. In the present study, we investigate the effect of a dihydrolipoic acid derivative lipoicmethylenedioxyphenol (LMDP) on the progression of atherosclerosis and test whether its effect on atherosclerosis is mediated by Nrf2. Methods and Results Both magnetic resonance imaging (MRI) scanning and en face analysis reveal that 14 weeks of treatment with LMDP markedly reduced atherosclerotic burden in a rabbit balloon vascular injury model. Myograph analyses show decreased aortic contractile response to phenylephrine and increased aortic response to acetylcholine and insulin in LMDP-treated animals, suggesting that LMDP inhibits atherosclerosis through improving vascular function. A role of Nrf2 signaling in mediating the amelioration of vascular function by LMDP was supported by increased Nrf2 translocation into nuclear and increased expression of Nrf2 target genes. Furthermore, chemotaxis analysis with Boydem chamber shows that leukocytes isolated from LMDP-treated rabbits had reduced chemotaxis, and knock-down of Nrf2 significantly reduced the effect of LMDP on the chemotaxis of mouse macrophages. Conclusion Our results support that LMDP has an anti-atherosclerotic effect likely through activation of Nrf2 signaling and subsequent inhibition of macrophage chemotaxis. PMID:26859892

  3. Scutellarein Reduces Inflammatory Responses by Inhibiting Src Kinase Activity

    PubMed Central

    Sung, Nak Yoon

    2015-01-01

    Flavonoids are plant pigments that have been demonstrated to exert various pharmacological effects including anti-cancer, anti-diabetic, anti-atherosclerotic, anti-bacterial, and anti-inflammatory activities. However, the molecular mechanisms in terms of exact target proteins of flavonoids are not fully elucidated yet. In this study, we aimed to evaluate the anti-inflammatory mechanism of scutellarein (SCT), a flavonoid isolated from Erigeron breviscapus, Clerodendrum phlomidis and Oroxylum indicum Vent that have been traditionally used to treat various inflammatory diseases in China and Brazil. For this purpose, a nitric oxide (NO) assay, polymerase chain reaction (PCR), nuclear fractionation, immunoblot analysis, a kinase assay, and an overexpression strategy were employed. Scutellarein significantly inhibited NO production in a dose-dependent manner and reduced the mRNA expression levels of inducible NO synthase (iNOS) and tumor necrosis factor (TNF)-α in lipopolysaccharide (LPS)-activated RAW264.7 cells. In addition, SCT also dampened nuclear factor (NF)-κB-driven expression of a luciferase reporter gene upon transfection of a TIR-domain-containing adapter-inducing interferon-β (TRIF) construct into Human embryonic kidney 293 (HEK 293) cells; similarly, NF-κ B nuclear translocation was inhibited by SCT. Moreover, the phosphorylation levels of various upstream signaling enzymes involved in NF-κB activation were decreased by SCT treatment in LPS-treated RAW264.7 cells. Finally, SCT strongly inhibited Src kinase activity and also inhibited the autophosphorylation of overexpressed Src. Therefore, our data suggest that SCT can block the inflammatory response by directly inhibiting Src kinase activity linked to NF-κB activation. PMID:26330757

  4. Meditation leads to reduced default mode network activity beyond an active task.

    PubMed

    Garrison, Kathleen A; Zeffiro, Thomas A; Scheinost, Dustin; Constable, R Todd; Brewer, Judson A

    2015-09-01

    Meditation has been associated with relatively reduced activity in the default mode network, a brain network implicated in self-related thinking and mind wandering. However, previous imaging studies have typically compared meditation to rest, despite other studies having reported differences in brain activation patterns between meditators and controls at rest. Moreover, rest is associated with a range of brain activation patterns across individuals that has only recently begun to be better characterized. Therefore, in this study we compared meditation to another active cognitive task, both to replicate the findings that meditation is associated with relatively reduced default mode network activity and to extend these findings by testing whether default mode activity was reduced during meditation, beyond the typical reductions observed during effortful tasks. In addition, prior studies had used small groups, whereas in the present study we tested these hypotheses in a larger group. The results indicated that meditation is associated with reduced activations in the default mode network, relative to an active task, for meditators as compared to controls. Regions of the default mode network showing a Group × Task interaction included the posterior cingulate/precuneus and anterior cingulate cortex. These findings replicate and extend prior work indicating that the suppression of default mode processing may represent a central neural process in long-term meditation, and they suggest that meditation leads to relatively reduced default mode processing beyond that observed during another active cognitive task. PMID:25904238

  5. Meditation leads to reduced default mode network activity beyond an active task

    PubMed Central

    Garrison, Kathleen A.; Zeffiro, Thomas A.; Scheinost, Dustin; Constable, R. Todd; Brewer, Judson A.

    2015-01-01

    Meditation has been associated with relatively reduced activity in the default mode network, a brain network implicated in self-related thinking and mind wandering. However, previous imaging studies have typically compared meditation to rest despite other studies reporting differences in brain activation patterns between meditators and controls at rest. Moreover, rest is associated with a range of brain activation patterns across individuals that has only recently begun to be better characterized. Therefore, this study compared meditation to another active cognitive task, both to replicate findings that meditation is associated with relatively reduced default mode network activity, and to extend these findings by testing whether default mode activity was reduced during meditation beyond the typical reductions observed during effortful tasks. In addition, prior studies have used small groups, whereas the current study tested these hypotheses in a larger group. Results indicate that meditation is associated with reduced activations in the default mode network relative to an active task in meditators compared to controls. Regions of the default mode showing a group by task interaction include the posterior cingulate/precuneus and anterior cingulate cortex. These findings replicate and extend prior work indicating that suppression of default mode processing may represent a central neural process in long-term meditation, and suggest that meditation leads to relatively reduced default mode processing beyond that observed during another active cognitive task. PMID:25904238

  6. Defect-induced enhanced photocatalytic activities of reduced α-Fe2O3 nanoblades.

    PubMed

    Feng, Honglei; Wang, Yiqian; Wang, Chao; Diao, Feiyu; Zhu, Wenhui; Mu, Peng; Yuan, Lu; Zhou, Guangwen; Rosei, Federico

    2016-07-22

    Bicrystalline α-Fe2O3 nanoblades (NBs) synthesized by thermal oxidation of iron foils were reduced in vacuum, to study the effect of reduction treatment on microstructural changes and photocatalytic properties. After the vacuum reduction, most bicrystalline α-Fe2O3 NBs transform into single-layered NBs, which contain more defects such as oxygen vacancies, perfect dislocations and dense pores. By comparing the photodegradation capability of non-reduced and reduced α-Fe2O3 NBs over model dye rhodamine B (RhB) in the presence of hydrogen peroxide, we find that vacuum-reduction induced microstructural defects can significantly enhance the photocatalytic efficiency. Even after 10 cycles, the reduced α-Fe2O3 NBs still show a very high photocatalytic activity. Our results demonstrate that defect engineering is a powerful tool to enhance the photocatalytic performance of nanomaterials. PMID:27285480

  7. Defect-induced enhanced photocatalytic activities of reduced α-Fe2O3 nanoblades

    NASA Astrophysics Data System (ADS)

    Feng, Honglei; Wang, Yiqian; Wang, Chao; Diao, Feiyu; Zhu, Wenhui; Mu, Peng; Yuan, Lu; Zhou, Guangwen; Rosei, Federico

    2016-07-01

    Bicrystalline α-Fe2O3 nanoblades (NBs) synthesized by thermal oxidation of iron foils were reduced in vacuum, to study the effect of reduction treatment on microstructural changes and photocatalytic properties. After the vacuum reduction, most bicrystalline α-Fe2O3 NBs transform into single-layered NBs, which contain more defects such as oxygen vacancies, perfect dislocations and dense pores. By comparing the photodegradation capability of non-reduced and reduced α-Fe2O3 NBs over model dye rhodamine B (RhB) in the presence of hydrogen peroxide, we find that vacuum-reduction induced microstructural defects can significantly enhance the photocatalytic efficiency. Even after 10 cycles, the reduced α-Fe2O3 NBs still show a very high photocatalytic activity. Our results demonstrate that defect engineering is a powerful tool to enhance the photocatalytic performance of nanomaterials.

  8. Activation of Melatonin Receptors Reduces Relapse-Like Alcohol Consumption.

    PubMed

    Vengeliene, Valentina; Noori, Hamid R; Spanagel, Rainer

    2015-12-01

    Melatonin is an endogenous synchronizer of biological rhythms and a modulator of physiological functions and behaviors of all mammals. Reduced levels of melatonin and a delay of its nocturnal peak concentration have been found in alcohol-dependent patients and rats. Here we investigated whether the melatonergic system is a novel target to treat alcohol addiction. Male Wistar rats were subjected to long-term voluntary alcohol consumption with repeated abstinence phases. Circadian drinking rhythmicity and patterns were registered with high temporal resolution by a drinkometer system and analyzed by Fourier analysis. We examined potential antirelapse effect of the novel antidepressant drug agomelatine. Given that agomelatine is a potent MT1 and MT2 receptor agonist and a 5-HT2C antagonist we also tested the effects of melatonin itself and the 5-HT2C antagonist SB242084. All drugs reduced relapse-like drinking. Agomelatine and melatonin administered at the end of the light phase led to very similar changes on all measures of the post-abstinence drinking behavior, suggesting that effects of agomelatine on relapse-like behavior are mostly driven by its melatonergic activity. Both drugs caused a clear phase advance in the diurnal drinking pattern when compared with the control vehicle-treated group and a reduced frequency of approaches to alcohol bottles. Melatonin given at the onset of the light phase had no effect on the circadian phase and very small effects on alcohol consumption. We conclude that targeting the melatonergic system in alcohol-dependent individuals can induce a circadian phase advance, which may restore normal sleep architecture and reduce relapse behavior. PMID:25994077

  9. New Configurations of Micro Plate-Fin Heat Sink to Reduce Coolant Pumping Power

    NASA Astrophysics Data System (ADS)

    Rezania, A.; Rosendahl, L. A.

    2012-06-01

    The thermal resistance of heat exchangers has a strong influence on the electric power produced by a thermoelectric generator (TEG). In this work, a real TEG device is applied to three configurations of micro plate-fin heat sink. The distance between certain microchannels is varied to find the optimum heat sink configuration. The particular focus of this study is to reduce the coolant mass flow rate by considering the thermal resistances of the heat sinks and, thereby, to reduce the coolant pumping power in the system. The three-dimensional governing equations for the fluid flow and the heat transfer are solved using the finite-volume method for a wide range of pressure drop laminar flows along the heat sink. The temperature and the mass flow rate distribution in the heat sink are discussed. The results, which are in good agreement with previous computational studies, show that using suggested heat sink configurations reduces the coolant pumping power in the system.

  10. Sequential activation of multiple grounding pads reduces skin heating during radiofrequency tumor ablation

    PubMed Central

    HAEMMERICH, DIETER; SCHUTT, DAVID JAMES

    2009-01-01

    Purpose Radiofrequency (RF) tumor ablation has become an accepted treatment modality for tumors not amenable to surgery. Skin burns due to ground pad heating may become a limiting factor for further increase in ablation zone dimensions and generator power. We investigated a method were groups of ground pads are sequentially activated to reduce skin heating. Methods We compared conventional operation (i.e. simultaneous connection of all pads) to sequentially switched activation of the pads where different pad combinations are active for periods of ∼0.3 − 8 s. The timing during sequential activation was adjusted to keep the leading edge temperature equal between the pads. We created Finite Element Method computer models of three pads (5 × 5 cm, 1 cm apart) placed in line with the RF electrode on a human thigh to determine differences in tissue heating during simultaneous and sequential ground pad activation. We performed experiments with three ground pads (5 × 10 cm, 4 cm apart) placed on a tissue phantom (1.5 A, 12 min) and measured pad surface and leading edge temperatures. Results Temperature rise below the leading edge for proximal, middle and distal ground pad in relation to active electrode location was 5.9°C ± 0.1°C, 0.8°C ± 0.1°C and 0.3°C ± 0.1°C for conventional operation, and 3.3°C ± 0.1°C, 3.4°C ± 0.2°C and 3.4°C ± 0.2°C for sequentially activated operation in the experiments (p < 0.001). Conclusion Sequential activation of multiple ground pads resulted in reduced maximum tissue temperature. This may reduce the incidence of ground pad burns and may allow higher power RF generators. PMID:18038286

  11. PARP1 Val762Ala polymorphism reduces enzymatic activity

    SciTech Connect

    Wang Xiaogan; Wang Zhaoqi; Tong Weimin . E-mail: tong@iarc.fr; Shen Yan

    2007-03-02

    Poly(ADP-ribose) polymerase 1 (PARP1) modifies a variety of nuclear proteins by poly(ADP-ribosyl)ation, and plays diverse roles in molecular and cellular processes. A common PARP1 single nucleotide polymorphism (SNP) at codon 762, resulting in the substitution of alanine (Ala) for valine (Val) in the catalytic domain has been implicated in susceptibility to cancer. To characterize the functional effect of this polymorphism on PARP1, we performed in vitro enzymatic analysis on PARP1-Ala762 and PARP1-Val762. We found that PARP1-Ala762 displayed 57.2% of the activity of PARP1-Val762 for auto-poly(ADP-ribosyl)ation and 61.9% of the activity of PARP1-Val762 for trans-poly(ADP-ribosyl)ation of histone H1. The kinetic characterization revealed that the K {sub m} of PARP1-Ala762 was increased to a 1.2-fold of the K {sub m} of PARP1-Val762 for trans-poly(ADP-ribosyl)ation. Thus, the PARP1 Val762Ala polymorphism reduces the enzymatic activity of PARP1 by increasing K {sub m}. This finding suggests that different levels of poly(ADP-ribosyl)ation by PARP1 might aid in understanding Cancer risk of carriers of the PARP1 Val762Ala polymorphism.

  12. The Role of Demand Response in Reducing Water-Related Power Plant Vulnerabilities

    NASA Astrophysics Data System (ADS)

    Macknick, J.; Brinkman, G.; Zhou, E.; O'Connell, M.; Newmark, R. L.; Miara, A.; Cohen, S. M.

    2015-12-01

    The electric sector depends on readily available water supplies for reliable and efficient operation. Elevated water temperatures or low water levels can trigger regulatory or plant-level decisions to curtail power generation, which can affect system cost and reliability. In the past decade, dozens of power plants in the U.S. have curtailed generation due to water temperatures and water shortages. Curtailments occur during the summer, when temperatures are highest and there is greatest demand for electricity. Climate change could alter the availability and temperature of water resources, exacerbating these issues. Constructing alternative cooling systems to address vulnerabilities can be capital intensive and can also affect power plant efficiencies. Demand response programs are being implemented by electric system planners and operators to reduce and shift electricity demands from peak usage periods to other times of the day. Demand response programs can also play a role in reducing water-related power sector vulnerabilities during summer months. Traditionally, production cost modeling and demand response analyses do not include water resources. In this effort, we integrate an electricity production cost modeling framework with water-related impacts on power plants in a test system to evaluate the impacts of demand response measures on power system costs and reliability. Specifically, we i) quantify the cost and reliability implications of incorporating water resources into production cost modeling, ii) evaluate the impacts of demand response measures on reducing system costs and vulnerabilities, and iii) consider sensitivity analyses with cooling systems to highlight a range of potential benefits of demand response measures. Impacts from climate change on power plant performance and water resources are discussed. Results provide key insights to policymakers and practitioners for reducing water-related power plant vulnerabilities via lower cost methods.

  13. Reducing power consumption while performing collective operations on a plurality of compute nodes

    DOEpatents

    Archer, Charles J.; Blocksome, Michael A.; Peters, Amanda E.; Ratterman, Joseph D.; Smith, Brian E.

    2011-10-18

    Methods, apparatus, and products are disclosed for reducing power consumption while performing collective operations on a plurality of compute nodes that include: receiving, by each compute node, instructions to perform a type of collective operation; selecting, by each compute node from a plurality of collective operations for the collective operation type, a particular collective operation in dependence upon power consumption characteristics for each of the plurality of collective operations; and executing, by each compute node, the selected collective operation.

  14. Method and apparatus for reducing coherence of high-power laser beams

    DOEpatents

    Moncur, Norman K.; Mayer, Frederick J.

    1978-01-01

    Method and apparatus for reducing the coherence and for smoothing the power density profile of a collimated high-power laser beam in which the beam is focused at a point on the surface of a target fabricated of material having a low atomic number. The initial portion of the focused beam heats the material to form a hot reflective plasma at the material surface. The remaining, major portion of the focused beam is reflected by the plasma and recollected to form a collimated beam having reduced beam coherence.

  15. System Design Techniques for Reducing the Power Requirements of Advanced life Support Systems

    NASA Technical Reports Server (NTRS)

    Finn, Cory; Levri, Julie; Pawlowski, Chris; Crawford, Sekou; Luna, Bernadette (Technical Monitor)

    2000-01-01

    The high power requirement associated with overall operation of regenerative life support systems is a critical Z:p technological challenge. Optimization of individual processors alone will not be sufficient to produce an optimized system. System studies must be used in order to improve the overall efficiency of life support systems. Current research efforts at NASA Ames Research Center are aimed at developing approaches for reducing system power and energy usage in advanced life support systems. System energy integration and energy reuse techniques are being applied to advanced life support, in addition to advanced control methods for efficient distribution of power and thermal resources. An overview of current results of this work will be presented. The development of integrated system designs that reuse waste heat from sources such as crop lighting and solid waste processing systems will reduce overall power and cooling requirements. Using an energy integration technique known as Pinch analysis, system heat exchange designs are being developed that match hot and cold streams according to specific design principles. For various designs, the potential savings for power, heating and cooling are being identified and quantified. The use of state-of-the-art control methods for distribution of resources, such as system cooling water or electrical power, will also reduce overall power and cooling requirements. Control algorithms are being developed which dynamically adjust the use of system resources by the various subsystems and components in order to achieve an overall goal, such as smoothing of power usage and/or heat rejection profiles, while maintaining adequate reserves of food, water, oxygen, and other consumables, and preventing excessive build-up of waste materials. Reductions in the peak loading of the power and thermal systems will lead to lower overall requirements. Computer simulation models are being used to test various control system designs.

  16. Direct charge radioisotope activation and power generation

    DOEpatents

    Lal, Amit; Li, Hui; Blanchard, James P.; Henderson, Douglass L.

    2002-01-01

    An activator has a base on which is mounted an elastically deformable micromechanical element that has a section that is free to be displaced toward the base. An absorber of radioactively emitted particles is formed on the base or the displaceable section of the deformable element and a source is formed on the other of the displaceable section or the base facing the absorber across a small gap. The radioactive source emits charged particles such as electrons, resulting in a buildup of charge on the absorber, drawing the absorber and source together and storing mechanical energy as the deformable element is bent. When the force between the absorber and the source is sufficient to bring the absorber into effective electrical contact with the source, discharge of the charge between the source and absorber allows the deformable element to spring back, releasing the mechanical energy stored in the element. An electrical generator such as a piezoelectric transducer may be secured to the deformable element to convert the released mechanical energy to electrical energy that can be used to provide power to electronic circuits.

  17. High-frequency TRNS reduces BOLD activity during visuomotor learning.

    PubMed

    Saiote, Catarina; Polanía, Rafael; Rosenberger, Konstantin; Paulus, Walter; Antal, Andrea

    2013-01-01

    Transcranial direct current stimulation (tDCS) and transcranial random noise stimulation (tRNS) consist in the application of electrical current of small intensity through the scalp, able to modulate perceptual and motor learning, probably by changing brain excitability. We investigated the effects of these transcranial electrical stimulation techniques in the early and later stages of visuomotor learning, as well as associated brain activity changes using functional magnetic resonance imaging (fMRI). We applied anodal and cathodal tDCS, low-frequency and high-frequency tRNS (lf-tRNS, 0.1-100 Hz; hf-tRNS 101-640 Hz, respectively) and sham stimulation over the primary motor cortex (M1) during the first 10 minutes of a visuomotor learning paradigm and measured performance changes for 20 minutes after stimulation ceased. Functional imaging scans were acquired throughout the whole experiment. Cathodal tDCS and hf-tRNS showed a tendency to improve and lf-tRNS to hinder early learning during stimulation, an effect that remained for 20 minutes after cessation of stimulation in the late learning phase. Motor learning-related activity decreased in several regions as reported previously, however, there was no significant modulation of brain activity by tDCS. In opposition to this, hf-tRNS was associated with reduced motor task-related-activity bilaterally in the frontal cortex and precuneous, probably due to interaction with ongoing neuronal oscillations. This result highlights the potential of lf-tRNS and hf-tRNS to differentially modulate visuomotor learning and advances our knowledge on neuroplasticity induction approaches combined with functional imaging methods. PMID:23527247

  18. Reducing power consumption during execution of an application on a plurality of compute nodes

    SciTech Connect

    Archer, Charles J.; Blocksome, Michael A.; Peters, Amanda E.; Ratterman, Joseph D.; Smith, Brian E.

    2013-09-10

    Methods, apparatus, and products are disclosed for reducing power consumption during execution of an application on a plurality of compute nodes that include: powering up, during compute node initialization, only a portion of computer memory of the compute node, including configuring an operating system for the compute node in the powered up portion of computer memory; receiving, by the operating system, an instruction to load an application for execution; allocating, by the operating system, additional portions of computer memory to the application for use during execution; powering up the additional portions of computer memory allocated for use by the application during execution; and loading, by the operating system, the application into the powered up additional portions of computer memory.

  19. Baicalein Reduces the Invasion of Glioma Cells via Reducing the Activity of p38 Signaling Pathway

    PubMed Central

    Lei, Xiaoming; Li, Siyuan; Zhang, Yong; Meng, Lihua; Xue, Rongliang; Li, Zongfang

    2014-01-01

    Baicalein, one of the major flavonids in Scutellaria baicalensis, has historically been used in anti-inflammatory and anti-cancer therapies. However, the anti-metastatic effect and related mechanism(s) in glioma are still unclear. In this study, we thus utilized glioma cell lines U87MG and U251MG to explore the effect of baicalein. We found that administration of baicalein significantly inhibited migration and invasion of glioma cells. In addition, after treating with baicalein for 24 h, there was a decrease in the levels of matrix metalloproteinase-2 (MMP-2) and MMP-9 expression as well as proteinase activity in glioma cells. Conversely, the expression of tissue inhibitor of metalloproteinase-1 (TIMP-1) and TIMP-2 was increased in a dose-dependent manner. Moreover, baicalein treatment significantly decreased the phosphorylated level of p38, but not ERK1/2, JNK1/2 and PI3K/Akt. Combined treatment with a p38 inhibitor (SB203580) and baicalein resulted in the synergistic reduction of MMP-2 and MMP-9 expression and then increase of TIMP-1 and TIMP-2 expression; and the invasive capabilities of U87MG cells were also inhibited. However, p38 chemical activator (anisomycin) could block these effects produced by baicalein, suggesting baicalein directly downregulate the p38 signaling pathway. In conclusion, baicalein inhibits glioma cells invasion and metastasis by reducing cell motility and migration via suppression of p38 signaling pathway, suggesting that baicalein is a potential therapeutic agent for glioma. PMID:24587321

  20. Effects of H2 and electrochemical reducing power on metabolite production by Clostridium acetobutylicum KCTC1037.

    PubMed

    Jeon, Boyoung; Yi, Junyeong; Park, Doohyun

    2014-01-01

    A conventional fermenter (CF), a single-cathode fermenter (SCF), and a double-cathode fermenter (DCF) were employed to evaluate and compare the effects of H2 and electrochemical reducing power on metabolite production by Clostridium acetobutylicum KCTC1037. The source of the external reducing power for CF was H2, for the SCF was electrochemically reduced neutral red-modified graphite felt electrode (NR-GF), and for the DCF was electrochemically reduced combination of NR-GF and platinum plate electrodes (NR-GF/PtP). The metabolites produced from glucose or CO2 by strain KCTC1037 cultivated in the DCF were butyrate, ethanol, and butanol, but ethanol and butanol were not produced from glucose or CO2 by strain KCTC1037 cultivated in the CF and SCF. It is possible that electrochemically reduced NR-GF/PtP is a more effective source of internal and external reducing power than H2 or NR-GF for strain KCTC1037 to produce metabolites from glucose and CO2. This research might prove useful in developing fermentation technology to actualize direct bioalcohol production of fermentation bacteria from CO2. PMID:25036842

  1. Agent-based power sharing scheme for active hybrid power sources

    NASA Astrophysics Data System (ADS)

    Jiang, Zhenhua

    The active hybridization technique provides an effective approach to combining the best properties of a heterogeneous set of power sources to achieve higher energy density, power density and fuel efficiency. Active hybrid power sources can be used to power hybrid electric vehicles with selected combinations of internal combustion engines, fuel cells, batteries, and/or supercapacitors. They can be deployed in all-electric ships to build a distributed electric power system. They can also be used in a bulk power system to construct an autonomous distributed energy system. An important aspect in designing an active hybrid power source is to find a suitable control strategy that can manage the active power sharing and take advantage of the inherent scalability and robustness benefits of the hybrid system. This paper presents an agent-based power sharing scheme for active hybrid power sources. To demonstrate the effectiveness of the proposed agent-based power sharing scheme, simulation studies are performed for a hybrid power source that can be used in a solar car as the main propulsion power module. Simulation results clearly indicate that the agent-based control framework is effective to coordinate the various energy sources and manage the power/voltage profiles.

  2. Effectiveness of US state policies in reducing CO2 emissions from power plants

    NASA Astrophysics Data System (ADS)

    Grant, Don; Bergstrand, Kelly; Running, Katrina

    2014-11-01

    President Obama's landmark initiative to reduce the CO2 emissions of existing power plants, the nation's largest source of greenhouse gas (GHG) pollutants, depends heavily on states and their ability to devise policies that meet the goals set by the Environmental Protection Agency (EPA). Under the EPA's proposed Clean Power Plan, states will be responsible for cutting power plants' carbon pollution 30% from 2005 levels by 2030. States have already adopted several policies to reduce the electricity sector's climate impact. Some of these policies focus on reducing power plants' CO2 emissions, and others address this outcome in a more roundabout fashion by encouraging energy efficiency and renewable energy. However, it remains unclear which, if any, of these direct and indirect strategies actually mitigate plants' emissions because scholars have yet to test their effects using plant-level emission data. Here we use a newly released data source to determine whether states' policies significantly shape individual power plants' CO2 emissions. Findings reveal that certain types of direct strategy (emission caps and GHG targets) and indirect ones (public benefit funds and electric decoupling) lower plants' emissions and thus are viable building blocks of a federal climate regime.

  3. Method for reducing fuel cell output voltage to permit low power operation

    DOEpatents

    Reiser, Carl A.; Landau, Michael B.

    1980-01-01

    Fuel cell performance is degraded by recycling a portion of the cathode exhaust through the cells and, if necessary, also reducing the total air flow to the cells for the purpose of permitting operation below a power level which would otherwise result in excessive voltage.

  4. Analysis of Strategies for Reducing Multiple Emissions from Electric Power Plants: SO2, Nox, CO2

    EIA Publications

    2001-01-01

    This report responds to a request received from Senator David McIntosh on June 29, 2000 to analyze the impacts on energy consumers and producers of coordinated strategies to reduce emissions of sulfur dioxide, nitrogen oxides, and carbon dioxide at U.S. power plants.

  5. A flexible active and reactive power control strategy for a variable speed constant frequency generating system

    SciTech Connect

    Tang, Y.; Xu, L.

    1995-07-01

    Variable-speed constant-frequency generating systems are used in wind power, hydro power, aerospace, and naval power generations to enhance efficiency and reduce friction. In these applications, an attractive candidate is the slip power recovery system comprising of doubly excited induction machine or doubly excited brushless reluctance machine and PWM converters with a dc link. In this paper, a flexible active and reactive power control strategy is developed, such that the optimal torque-speed profile of the turbine can be followed and overall reactive power can be controlled, while the machine copper losses have been minimized. At the same time, harmonics injected into the power network has also been minimized. In this manner, the system can function as both a high-efficient power generator and a flexible reactive power compensator.

  6. Cathepsin G activity lowers plasma LDL and reduces atherosclerosis

    PubMed Central

    Wang, Jing; Sjöberg, Sara; Tang, Ting-Ting; Öörni, Katariina; Wu, Wenxue; Liu, Conglin; Secco, Blandine; Tia, Viviane; Sukhova, Galina K.; Fernandes, Cleverson; Lesner, Adam; Kovanen, Petri T.; Libby, Peter; Cheng, Xiang; Shi, Guo-Ping

    2014-01-01

    Cathepsin G (CatG), a serine protease present in mast cells and neutrophils, can produce angiotensin-II (Ang-II) and degrade elastin. Here we demonstrate increased CatG expression in smooth muscle cells (SMCs), endothelial cells (ECs), macrophages, and T cells from human atherosclerotic lesions. In low-density lipoprotein (LDL) receptor-deficient (Ldlr−/−) mice, the absence of CatG reduces arterial wall elastin degradation and attenuates early atherosclerosis when mice consume a Western diet for 3 months. When mice consume this diet for 6 months, however, CatG deficiency exacerbates atherosclerosis in aortic arch without affecting lesion inflammatory cell content or extracellular matrix accumulation, but raises plasma total cholesterol and LDL levels without affecting high-density lipoprotein (HDL) or triglyceride levels. Patients with atherosclerosis also have significantly reduced plasma CatG levels that correlate inversely with total cholesterol (r= −0.535, P<0.0001) and LDL cholesterol (r= −0.559, P<0.0001), but not with HDL cholesterol (P=0.901) or triglycerides (P=0.186). Such inverse correlations with total cholesterol (r= −0.504, P<0.0001) and LDL cholesterol (r= −0.502, P<0.0001) remain significant after adjusting for lipid lowering treatments among this patient population. Human CatG degrades purified human LDL, but not HDL. This study suggests that CatG promotes early atherogenesis through its elastinolytic activity, but suppresses late progression of atherosclerosis by degrading LDL without affecting HDL or triglycerides. PMID:25092171

  7. Low-power MOEMS components for active optical systems

    NASA Astrophysics Data System (ADS)

    Castracane, James; Yan, Dong; Madison, Seth; Xu, Bai

    2004-01-01

    The eventual, widespread insertion of Micro-Opto-Electro-Mechanical Systems (MOEMS) into the marketplace rests fundamentally on the ability to produce viable components that maximize optical performance while minimizing power consumption and size. In addition, the incorporation of optical reconfigurability into custom MOEMS devices offers an extra degree of freedom not possible with conventional components. Active control of surface topology allows for one component to perform multiple functions thus reducing cost and complexity. This paper will focus on the current status of the MOEMS research program at the University at Albany Institute for Materials" (UAIM) NanoFab 200 with several examples described to illustrate component and system development. In particular, among the MOEMS research portfolio at UAIM, the development of selected MOEMS-based, active optics will be discussed. This active control of diffraction and reflection forms the basis for the utility of such devices. Leveraging the extensive research expertise on the patented MEMS Compound Grating (MCG), emphasis will be placed on the extension of the approach to novel designs, materials and fabrication methods to yield low power, high performance prototypes. The main focus of this paper is on the development of a polymer version (including sacrificial layer, in some designs) of the MCG which allows for ease of fabrication and a reduced electrostatic actuation voltage. Following a system design effort, several generations of the component were fabricated to optimize the process flow. Component metrology, electromechanical characterization and initial results of optical tests will be reported. A second example presented is the design and prototype fabrication of a spring micrograting using a customized SOI process. This highly flexible component builds on the MCG concept and yields an order of magnitude reduction in actuation voltage. These examples will be presented against a backdrop of the broad UAIM

  8. On Reducing Test Power, Volume and Routing Cost by Chain Reordering and Test Compression Techniques

    NASA Astrophysics Data System (ADS)

    Lin, Chia-Yi; Hsu, Li-Chung; Chen, Hung-Ming

    With the advancement of VLSI manufacturing technology, entire electronic systems can be implemented in a single integrated circuit. Due to the complexity in SoC design, circuit testability becomes one of the most challenging works. Without careful planning in Design For Testability (DFT) design, circuits consume more power in test mode operation than that in normal functional mode. This elevated testing power may cause problems including overall yield lost and instant circuit damage. In this paper, we present two approaches to minimize scan based DFT power dissipation. First methodology includes routing cost consideration in scan chain reordering after cell placement, while second methodology provides test pattern compression for lower power. We formulate the first problem as a Traveling Salesman Problem (TSP), with different cost evaluation from [18], [19], and apply an efficient heuristic to solve it. In the second problem, we provide a selective scan chain architecture and perform a simple yet effective encoding scheme for lower scan testing power dissipation. The experimental results of ISCAS'89 benchmarks show that the first methodology obtains up to 10% average power saving under the same low routing cost compared with a recent result in [19]. The second methodology reduces over 17% of test power compared with filling all don't care (X) bit with 0 in one of ISCAS'89 benchmarks. We also provide the integration flow of these two approaches in this paper.

  9. Tritium retention in reduced-activation ferritic/martensitic steels

    SciTech Connect

    Hatano, Y.; Abe, S.; Matsuyama, M.; Alimov, V.K.; Spitsyn, A.V.; Bobyr, N.P.; Cherkez, D.I.; Khripunov, B.I.; Golubeva, A.V.; Ogorodnikova, O.V.; Klimov, N.S.; Chernov, V.M.; Oyaidzu, M.; Yamanishi, T.

    2015-03-15

    Reduced-activation ferritic/martensitic (RAFM) steels are structural material candidates for breeding blankets of future fusion reactors. Therefore, tritium (T) retention in RAFM steels is an important problem in assessing the T inventory of blankets. In this study, specimens of RAFM steels were subjected to irradiation of 20 MeV W ions to 0.54 displacements per atom (dpa), exposure to high flux D plasmas at 400 and 600 K and that to pulsed heat loads. The specimens thus prepared were exposed to DT gas at 473 K. Despite severe modification in the surface morphology, heat loads had negligible effects on T retention. Significant increase in T retention at the surface and/or subsurface was observed after D plasma exposure. However, T trapped at the surface/subsurface layer was easily removed by maintaining the specimens in the air at about 300 K. Displacement damage led to increase in T retention in the bulk due to the trapping effects of defects, and T trapped was stable at 300 K. It was therefore concluded that displacement damages had the largest influence on T retention under the present conditions.

  10. Materials design data for reduced activation martensitic steel type EUROFER

    NASA Astrophysics Data System (ADS)

    Tavassoli, A.-A. F.; Alamo, A.; Bedel, L.; Forest, L.; Gentzbittel, J.-M.; Rensman, J.-W.; Diegele, E.; Lindau, R.; Schirra, M.; Schmitt, R.; Schneider, H. C.; Petersen, C.; Lancha, A.-M.; Fernandez, P.; Filacchioni, G.; Maday, M. F.; Mergia, K.; Boukos, N.; Baluc; Spätig, P.; Alves, E.; Lucon, E.

    2004-08-01

    Materials design limits derived so far from the data generated in Europe for the reduced activation ferritic/martensitic (RAFM) steel type Eurofer are presented. These data address the short-term needs of the ITER Test Blanket Modules and a DEMOnstration fusion reactor. Products tested include plates, bars, tubes, TIG and EB welds, as well as powder consolidated blocks and solid-solid HIP joints. Effects of thermal ageing and low dose neutron irradiation are also included. Results are sorted and screened according to design code requirements before being introduced in reference databases. From the physical properties databases, variations of magnetic properties, modulus of elasticity, density, thermal conductivity, thermal diffusivity, specific heat, mean and instantaneous linear coefficients of thermal expansion versus temperature are derived. From the tensile and creep properties databases design allowable stresses are derived. From the instrumented Charpy impact and fracture toughness databases, ductile to brittle transition temperature, toughness and behavior of materials in different fracture modes are evaluated. From the fatigue database, total strain range versus number of cycles to failure curves are plotted and used to derive fatigue design curves. Cyclic curves are also derived and compared with monotonic hardening curves. Finally, irradiated and aged materials data are compared to ensure that the safety margins incorporated in unirradiated design limits are not exceeded.

  11. Waste Management Strategy for Dismantling Waste to Reduce Costs for Power Plant Decommissioning - 13543

    SciTech Connect

    Larsson, Arne; Lidar, Per; Bergh, Niklas; Hedin, Gunnar

    2013-07-01

    Decommissioning of nuclear power plants generates large volumes of radioactive or potentially radioactive waste. The proper management of the dismantling waste plays an important role for the time needed for the dismantling phase and thus is critical to the decommissioning cost. An efficient and thorough process for inventorying, characterization and categorization of the waste provides a sound basis for the planning process. As part of comprehensive decommissioning studies for Nordic NPPs, Westinghouse has developed the decommissioning inventories that have been used for estimations of the duration of specific work packages and the corresponding costs. As part of creating the design basis for a national repository for decommissioning waste, the total production of different categories of waste packages has also been predicted. Studsvik has developed a risk based concept for categorization and handling of the generated waste using six different categories with a span from extremely small risk for radiological contamination to high level waste. The two companies have recently joined their skills in the area of decommissioning on selected market in a consortium named 'ndcon' to further strengthen the proposed process. Depending on the risk for radiological contamination or the radiological properties and other properties of importance for waste management, treatment routes are proposed with well-defined and proven methods for on-site or off-site treatment, activity determination and conditioning. The system is based on a graded approach philosophy aiming for high confidence and sustainability, aiming for re-use and recycling where found applicable. The objective is to establish a process where all dismantled material has a pre-determined treatment route. These routes should through measurements, categorization, treatment, conditioning, intermediate storage and final disposal be designed to provide a steady, un-disturbed flow of material to avoid interruptions. Bottle

  12. Power budget considerations for optically activated conventional sensors and actuators

    NASA Astrophysics Data System (ADS)

    Liu, Kexing

    1991-02-01

    Optically powered conventional instrumentation with optical fiber links that combine the advantages of a familiar technology and of fiber optics is described. A number of examples are given of the development of pneumatic pressure sensors and actuators with reduced power consumption that are operated by optical power and incorporated with fiber-optic links. Their performance and power budget are discussed. They are particularly applicable to transmissions through regions having high EM interference, high EM pulses, and explosive, radiative, or corrosive hazards, such as in nuclear power plants, process plants, aircraft, or spacecraft. These low-optical-power transmission and operation characteristics will help to meet safety requirements and to reduce the system cost.

  13. Constitutive adipocyte mTORC1 activation enhances mitochondrial activity and reduces visceral adiposity in mice.

    PubMed

    Magdalon, Juliana; Chimin, Patricia; Belchior, Thiago; Neves, Rodrigo X; Vieira-Lara, Marcel A; Andrade, Maynara L; Farias, Talita S; Bolsoni-Lopes, Andressa; Paschoal, Vivian A; Yamashita, Alex S; Kowaltowski, Alicia J; Festuccia, William T

    2016-05-01

    Mechanistic target of rapamycin complex 1 (mTORC1) loss of function reduces adiposity whereas partial mTORC1 inhibition enhances fat deposition. Herein we evaluated how constitutive mTORC1 activation in adipocytes modulates adiposity in vivo. Mice with constitutive mTORC1 activation in adipocytes induced by tuberous sclerosis complex (Tsc)1 deletion and littermate controls were evaluated for body mass, energy expenditure, glucose and fatty acid metabolism, mitochondrial function, mRNA and protein contents. Adipocyte-specific Tsc1 deletion reduced visceral, but not subcutaneous, fat mass, as well as adipocyte number and diameter, phenotypes that were associated with increased lipolysis, UCP-1 content (browning) and mRNA levels of pro-browning transcriptional factors C/EBPβ and ERRα. Adipocyte Tsc1 deletion enhanced mitochondrial oxidative activity, fatty acid oxidation and the expression of PGC-1α and PPARα in both visceral and subcutaneous fat. In brown adipocytes, however, Tsc1 deletion did not affect UCP-1 content and basal respiration. Adipocyte Tsc1 deletion also reduced visceral adiposity and enhanced glucose tolerance, liver and muscle insulin signaling and adiponectin secretion in mice fed with purified low- or high-fat diet. In conclusion, adipocyte-specific Tsc1 deletion enhances mitochondrial activity, induces browning and reduces visceral adiposity in mice. PMID:26923434

  14. Cost-effective retrofit technology for reducing peak power demand in small and medium commercial buildings

    SciTech Connect

    Nutaro, James J.; Fugate, David L.; Kuruganti, Teja; Sanyal, Jibonananda; Starke, Michael R.

    2015-05-27

    We describe a cost-effective retrofit technology that uses collective control of multiple rooftop air conditioning units to reduce the peak power consumption of small and medium commercial buildings. The proposed control uses a model of the building and air conditioning units to select an operating schedule for the air conditioning units that maintains a temperature set point subject to a constraint on the number of units that may operate simultaneously. A prototype of this new control system was built and deployed in a large gymnasium to coordinate four rooftop air conditioning units. Based on data collected while operating this prototype, we estimate that the cost savings achieved by reducing peak power consumption is sufficient to repay the cost of the prototype within a year.

  15. Calibration of Reduced Dynamic Models of Power Systems using Phasor Measurement Unit (PMU) Data

    SciTech Connect

    Zhou, Ning; Lu, Shuai; Singh, Ruchi; Elizondo, Marcelo A.

    2011-09-23

    Accuracy of a power system dynamic model is essential to the secure and efficient operation of the system. Lower confidence on model accuracy usually leads to conservative operation and lowers asset usage. To improve model accuracy, identification algorithms have been developed to calibrate parameters of individual components using measurement data from staged tests. To facilitate online dynamic studies for large power system interconnections, this paper proposes a model reduction and calibration approach using phasor measurement unit (PMU) data. First, a model reduction method is used to reduce the number of dynamic components. Then, a calibration algorithm is developed to estimate parameters of the reduced model. This approach will help to maintain an accurate dynamic model suitable for online dynamic studies. The performance of the proposed method is verified through simulation studies.

  16. Cost-effective retrofit technology for reducing peak power demand in small and medium commercial buildings

    DOE PAGESBeta

    Nutaro, James J.; Fugate, David L.; Kuruganti, Teja; Sanyal, Jibonananda; Starke, Michael R.

    2015-05-27

    We describe a cost-effective retrofit technology that uses collective control of multiple rooftop air conditioning units to reduce the peak power consumption of small and medium commercial buildings. The proposed control uses a model of the building and air conditioning units to select an operating schedule for the air conditioning units that maintains a temperature set point subject to a constraint on the number of units that may operate simultaneously. A prototype of this new control system was built and deployed in a large gymnasium to coordinate four rooftop air conditioning units. Based on data collected while operating this prototype,more » we estimate that the cost savings achieved by reducing peak power consumption is sufficient to repay the cost of the prototype within a year.« less

  17. Reducing Overheating-Induced Failures Via Performance-Aware CPU Power Management.

    SciTech Connect

    Hsu, C.-H.; Feng, W. C.

    2005-01-01

    Cluster end-users and administrators have become more cognizant of the fact that large-scale commodity clusters fail quite frequently, and the main source of these failures is hardware (e.g., processors) with the primary cause being heat. This situation is expected to worsen with even larger-scale clusters powered by faster (and/or multicore) processors. In this paper, we propose a power-management algorithm that addresses heat-related reliability for processors by controlling their clock speeds in a performance-aware manner. This approach is complementary to existing approaches such as exotic cooling and fault-tolerant technologies in that it proactively deals with power and cooling issues before they become a problem. Our preliminary experimental work demonstrates that our approach can easily be applied commodity processors and can reduce heat generation by 30% on average with minimal effect on performance when running the SPEC benchmarks.

  18. Delivering better power: the role of simulation in reducing the environmental impact of aircraft engines.

    PubMed

    Menzies, Kevin

    2014-08-13

    The growth in simulation capability over the past 20 years has led to remarkable changes in the design process for gas turbines. The availability of relatively cheap computational power coupled to improvements in numerical methods and physical modelling in simulation codes have enabled the development of aircraft propulsion systems that are more powerful and yet more efficient than ever before. However, the design challenges are correspondingly greater, especially to reduce environmental impact. The simulation requirements to achieve a reduced environmental impact are described along with the implications of continued growth in available computational power. It is concluded that achieving the environmental goals will demand large-scale multi-disciplinary simulations requiring significantly increased computational power, to enable optimization of the airframe and propulsion system over the entire operational envelope. However even with massive parallelization, the limits imposed by communications latency will constrain the time required to achieve a solution, and therefore the position of such large-scale calculations in the industrial design process. PMID:25024416

  19. Modelling pellet-clad mechanical interaction during extended reduced power operation in bonded nuclear fuel

    NASA Astrophysics Data System (ADS)

    Haynes, T. A.; Ball, J. A.; Shea, J. H.; Wenman, M. R.

    2015-10-01

    A 2D-rӨ model of pellet-clad mechanical interaction in advanced gas-cooled reactor fuel is presented. An incipient 5 μm crack is introduced into the inner surface of cladding bonded to a detachable sliver of fuel. Micro-cracking in the sliver is accounted for through a reduced elastic modulus. A test transient consisting of a hold at 70% power for 720 h was applied to the model. The competing effects of the closure of pellet cracks due to irradiation creep in inner regions of the pellet during extended low power operation, and that of thermal creep in the cladding whilst at reduced power alleviating this are investigated. In colder elements, the effect of irradiation creep dominates. In hotter elements, the effect of cladding creep at low power dominates. It was found that adjusting factors related to the pellet shape were unimportant; the sliver thickness, sliver shape and initial pellet crack width had only a small effect upon the extent of PCMI. Adjusting factors relating to the shape of the incipient crack such as the crack radius and depth had a significant effect; as did adjusting the elastic modulus reduction factor accounting for ladder cracking in the sliver and the coefficient of friction used throughout the model. The resulting model was able to predict the trend in average clad bore crack depth with axial position in the core observed in post irradiation examination.

  20. Cerium Oxide Nanoparticles Reduce Microglial Activation and Neurodegenerative Events in Light Damaged Retina

    PubMed Central

    Fiorani, Lavinia; Passacantando, Maurizio; Santucci, Sandro; Di Marco, Stefano; Bisti, Silvia; Maccarone, Rita

    2015-01-01

    The first target of any therapy for retinal neurodegeneration is to slow down the progression of the disease and to maintain visual function. Cerium oxide or ceria nanoparticles reduce oxidative stress, which is known to play a pivotal role in neurodegeneration. Our aim was to investigate whether cerium oxide nanoparticles were able to mitigate neurodegeneration including microglial activation and related inflammatory processes induced by exposure to high intensity light. Cerium oxide nanoparticles were injected intravitreally or intraveinously in albino Sprague-Dawley rats three weeks before exposing them to light damage of 1000 lux for 24 h. Electroretinographic recordings were performed a week after light damage. The progression of retinal degeneration was evaluated by measuring outer nuclear layer thickness and TUNEL staining to quantify photoreceptors death. Immunohistochemical analysis was used to evaluate retinal stress, neuroinflammatory cytokines and microglial activation. Only intravitreally injected ceria nanoparticles were detected at the level of photoreceptor outer segments 3 weeks after the light damage and electoretinographic recordings showed that ceria nanoparticles maintained visual response. Moreover, this treatment reduced neuronal death and “hot spot” extension preserving the outer nuclear layer morphology. It is noteworthy that in this work we demonstrated, for the first time, the ability of ceria nanoparticles to reduce microglial activation and their migration toward outer nuclear layer. All these evidences support ceria nanoparticles as a powerful therapeutic agent in retinal neurodegenerative processes. PMID:26469804

  1. Activation of protease-activated receptor 2 reduces glioblastoma cell apoptosis

    PubMed Central

    2014-01-01

    Background The pathogenesis of glioma is unclear. The disturbance of the apoptosis process plays a critical role in glioma growth. Factors regulating the apoptosis process are to be further understood. This study aims to investigate the role of protease activated receptor-2 (PAR2) in regulation the apoptosis process in glioma cells. Results The results showed that U87 cells and human glioma tissue expressed PAR2. Exposure to tryptase, or the PAR2 active peptide, increased STAT3 phosphorylation in the radiated U87 cells, reduced U87 cell apoptosis, suppressed the expression of p53 in U87 cells. Conclusions Activation of PAR2 can reduce the radiated U87 cell apoptosis via modulating the expression of p53. The results implicate that PAR2 may be a novel therapeutic target in the treatment of glioma. PMID:24670244

  2. Active Faults and Nuclear Power Plants

    NASA Astrophysics Data System (ADS)

    Chapman, Neil; Berryman, Kelvin; Villamor, Pilar; Epstein, Woody; Cluff, Lloyd; Kawamura, Hideki

    2014-01-01

    The destruction of the Fukushima Daiichi Nuclear Power Plant (NPP) following the March 2011 Tohoku earthquake and tsunami brought into sharp focus the susceptibility of NPPs to natural hazards. This is not a new issue—seismic hazard has affected the development of plants in the United States, and volcanic hazard was among the reasons for not commissioning the Bataan NPP in the Philippines [Connor et al., 2009].

  3. Low-Power 2-MHz Pulsed-Wave Transcranial Ultrasound Reduces Ischemic Brain Damage in Rats.

    PubMed

    Alexandrov, Andrei V; Barlinn, Kristian; Strong, Roger; Alexandrov, Anne W; Aronowski, Jaroslaw

    2011-09-01

    It is largely unknown whether prolonged insonation with ultrasound impacts the ischemic brain tissue by itself. Our goal was to evaluate safety and the effect of high-frequency ultrasound on infarct volume in rats. Thirty-two Long-Evans rats with permanent middle cerebral and carotid artery occlusions received either 2-MHz ultrasound at two levels of insonation power (128 or 10 mW) or no ultrasound (controls). We measured cerebral hemorrhage, indirect and direct infarct volume as well as edema volume at 24 h. No cerebral hemorrhages were detected in all animals. Exposure to low-power (10 mW) ultrasound resulted in a significantly decreased indirect infarct volume (p = 0.0039), direct infarct volume (p = 0.0031), and brain edema volume (p = 0.01) compared with controls. High-power (128 mW) ultrasound had no significant effects. An additional experiment with India ink showed a greater intravascular penetration of dye into ischemic tissues exposed to low-power ultrasound. Insonation with high-frequency, low-power ultrasound reduces ischemic brain damage in rat. Its effect on edema reduction and possible promotion of microcirculation could be used to facilitate drug and nutrient delivery to ischemic areas. PMID:24323655

  4. OTRA-THS MAC to reduce Power Outage Data Collection Latency in a smart meter network

    SciTech Connect

    Garlapati, Shravan K; Kuruganti, Phani Teja; Buehrer, Richard M; Reed, Jeffrey H

    2014-01-01

    The deployment of advanced metering infrastructure by the electric utilities poses unique communication challenges, particularly as the number of meters per aggregator increases. During a power outage, a smart meter tries to report it instantaneously to the electric utility. In a densely populated residential/industrial locality, it is possible that a large number of smart meters simultaneously try to get access to the communication network to report the power outage. If the number of smart meters is very high of the order of tens of thousands (metropolitan areas), the power outage data flooding can lead to Random Access CHannel (RACH) congestion. Several utilities are considering the use of cellular network for smart meter communications. In 3G/4G cellular networks, RACH congestion not only leads to collisions, retransmissions and increased RACH delays, but also has the potential to disrupt the dedicated traffic flow by increasing the interference levels (3G CDMA). In order to overcome this problem, in this paper we propose a Time Hierarchical Scheme (THS) that reduces the intensity of power outage data flooding and power outage reporting delay by 6/7th, and 17/18th when compared to their respective values without THS. Also, we propose an Optimum Transmission Rate Adaptive (OTRA) MAC to optimize the latency in power outage data collection. The analysis and simulation results presented in this paper show that both the OTRA and THS features of the proposed MAC results in a Power Outage Data Collection Latency (PODCL) that is 1/10th of the 4G LTE PODCL.

  5. Sustainable Buildings. Using Active Solar Power

    SciTech Connect

    Sharp, M. Keith; Barnett, Russell

    2015-04-20

    The objective of this project is to promote awareness and knowledge of active solar energy technologies by installing and monitoring the following demonstration systems in Kentucky: 1) Pool heating system, Churchill Park School, 2) Water heating and daylighting systems, Middletown and Aiken Road Elementary Schools, 3) Photovoltaic street light comparison, Louisville Metro, 4) up to 25 domestic water heating systems across Kentucky. These tasks will be supported by outreach activities, including a solar energy installer training workshop and a Kentucky Solar Energy Conference.

  6. The effects of bicycle frame geometry on muscle activation and power during a wingate anaerobic test.

    PubMed

    Ricard, Mark D; Hills-Meyer, Patrick; Miller, Michael G; Michael, Timothy J

    2006-01-01

    The purpose of this study was to compare the effects of bicycle seat tube angles (STA) of (72° and 82°) on power production and EMG of the vastus laeralis (VL), vastus medialis (VM), semimembranous (SM), biceps femoris (BF) during a Wingate test (WAT). Twelve experienced cyclists performed a WAT at each STA. Repeated measures ANOVA was used to identify differences in muscular activation by STA. EMG variables were normalized to isometric maximum voluntary contraction (MVC). Paired t-tests were used to test the effects of STA on: peak power, average power, minimum power and percent power drop. Results indicated BF activation was significantly lower at STA 82° (482.9 ± 166.6 %MVC·s) compared to STA 72° (712.6 ± 265.6 %MVC·s). There were no differences in the power variables between STAs. The primary finding was that increasing the STA from 72° to 82° enabled triathletes' to maintain power production, while significantly reducing the muscular activation of the biceps femoris muscle. Key PointsRoad cyclists claim that bicycle seat tube angles between 72° and 76° are most effective for optimal performance in racing.Triathletes typically use seat tube angles greater than 76°. It is thought that a seat tube angle greater than 76° facilitates a smoother bike to run transition in the triathlon.Increasing the seat tube angle from 72 to 82 enabled triathletes' to maintain power production, while significantly reducing the muscular activation of the biceps femoris muscle.Reduced hamstring muscular activation in the triathlon frame (82 seat tube angle) may serve to reduce hamstring tightness following the bike phase of the triathlon, allowing the runner to use a longer stride length. PMID:24198678

  7. Iron (FeII) Chelation, Ferric Reducing Antioxidant Power, and Immune Modulating Potential of Arisaema jacquemontii (Himalayan Cobra Lily)

    PubMed Central

    Sudan, Rasleen; Bhagat, Madhulika; Singh, Jasvinder; Koul, Anupurna

    2014-01-01

    This study explored the antioxidant and immunomodulatory potential of ethnomedicinally valuable species, namely, Arisaema jacquemontii of north-western Himalayan region. The tubers, leaves, and fruits of this plant were subjected to extraction using different solvents. In vitro antioxidant studies were performed in terms of chelation power on ferrous ions and FRAP assay. The crude methanol extract of leaves was found to harbour better chelating capacity (58% at 100 μg/mL) and reducing power (FRAP value 1085.4 ± 0.11 μMFe3+/g dry wt.) than all the other extracts. The crude methanol extract was thus further partitioned with solvents to yield five fractions. Antioxidant study of fractions suggested that the methanol fraction possessed significant chelation capacity (49.7% at 100 μg/mL) and reducing power with FRAP value of 1435.4 μM/g dry wt. The fractions were also studied for immune modulating potential where it was observed that hexane fraction had significant suppressive effect on mitogen induced T-cell and B-cell proliferation and remarkable stimulating effect on humoral response by 141% and on DTH response by 168% in immune suppressed mice as compared to the controls. Therefore, it can be concluded that A. jacquemontii leaves hold considerable antioxidant and immunomodulating potential and they can be explored further for the identification of their chemical composition for a better understanding of their biological activities. PMID:24895548

  8. Reducing start-up time and minimizing energy losses of Microbial Fuel Cells using Maximum Power Point Tracking strategy

    NASA Astrophysics Data System (ADS)

    Molognoni, Daniele; Puig, Sebastià; Balaguer, M. Dolors; Liberale, Alessandro; Capodaglio, Andrea G.; Callegari, Arianna; Colprim, Jesús

    2014-12-01

    Microbial Fuel Cells (MFCs) are considered to be an environmental friendly energy conversion technology. The main limitations that delay their industrialization include low current and power densities achievable and long start-up times. Maximum Power Point Tracking (MPPT) has been proposed as a method to enhance MFCs electrical performances. However, the specialized literature is still lacking of experimental works on scaled-up reactors and/or real wastewater utilization. This study evaluates the impact of a MPPT system applied to MFCs treating swine wastewater in terms of start-up time and long-term performance. For this purpose, two replicate cells were compared, one with applied MPPT control and one working with fixed resistance. Both MFCs were continuously fed with swine wastewater to validate the control system under real and dynamic conditions. The study demonstrated that the automatic resistance control was able to reduce the start-up time of about one month. Moreover, MPPT system increased of 40% the Coulombic efficiency at steady-state conditions, reduced energy losses associated with anode and cathode reactions and limited methanogenic activity in the anode chamber. A power density of 5.0 ± 0.2 W m-3 NAC was achieved feeding the system at an organic loading rate of 10 kg COD m-3 d-1.

  9. Piano Playing Reduces Stress More than Other Creative Art Activities

    ERIC Educational Resources Information Center

    Toyoshima, Kumiko; Fukui, Hajime; Kuda, Kiyoto

    2011-01-01

    Few studies have been conducted on the physiological effects of creative art activities. In this study, the effects of creative art activities on human stress were investigated, and their effects were compared in 57 healthy college students (27 males and 30 females). Subjects were divided into four groups, each of which participated in 30-minute…

  10. The central power source in active galaxies

    NASA Astrophysics Data System (ADS)

    Ptak, Roger; Stoner, Ronald

    Potential sources for the central power in AGN are examined. The continuum, emission line profiles, and time variability and broad emission line region for AGN are analyzed. The supermassive black hole hypothesis, the supermassive magnetized core model of Kundt (1978), and the model of Stoner and Ptak (1984) in which the supermassive stars maintain a kind of long-term quasi-stability, but accretion is balanced by mass loss and spherical bursts rather than in jets are considered. It is argued that the hypothesis that the supermassive blackholes are the central engines for AGN is based on theoretical principles; however, AGN emission line profiles and variability suggest a spherical geometry for the observed components of these engines. Also the supermassive black hole models do not account for all the AGN observations.

  11. USE OF COAL DRYING TO REDUCE WATER CONSUMED IN PULVERIZED COAL POWER PLANTS

    SciTech Connect

    Edward K. Levy; Nenad Sarunac; Harun Bilirgen; Hugo Caram

    2006-03-01

    U.S. low rank coals contain relatively large amounts of moisture, with the moisture content of subbituminous coals typically ranging from 15 to 30 percent and that for lignites from 25 and 40 percent. High fuel moisture has several adverse impacts on the operation of a pulverized coal generating unit, for it can result in fuel handling problems and it affects heat rate, stack emissions and maintenance costs. Theoretical analyses and coal test burns performed at a lignite fired power plant show that by reducing the fuel moisture, it is possible to improve boiler performance and unit heat rate, reduce emissions and reduce water consumption by the evaporative cooling tower. The economic viability of the approach and the actual impact of the drying system on water consumption, unit heat rate and stack emissions will depend critically on the design and operating conditions of the drying system. The present project evaluated the low temperature drying of high moisture coals using power plant waste heat to provide the energy required for drying. Coal drying studies were performed in a laboratory scale fluidized bed dryer to gather data and develop models on drying kinetics. In addition, analyses were carried out to determine the relative costs and performance impacts (in terms of heat rate, cooling tower water consumption and emissions) of drying along with the development of optimized drying system designs and recommended operating conditions.

  12. Reduction in Power Consumption for Full-Color Active Matrix Organic Light-Emitting Devices

    NASA Astrophysics Data System (ADS)

    Kanno, Hiroshi; Hamada, Yuji; Nishimura, Kazuki; Okumoto, Kenji; Saito, Nobuo; Mameno, Kazunobu; Shibata, Kenichi

    2006-09-01

    The active matrix organic light-emitting diode (AMOLED) is expected to serve as next generation flat panels display with the outstanding features of wide viewing angle, vivid images, and quick response. For practical use of full-color AMOLEDs in mobile devices, it is essential to reduce the power consumption, which is generally higher than that of liquid crystal displays (LCDs). For this aim, a red, green, blue, and white (RGBW) pixel format combined with an RGB color filter array (RGBW format) with a common white emission layer (EML) has been developed. We find that the RGBW format can successfully reduce the power consumption of a full-color AMOLED by nearly half that of a conventionally filtered RGB pixel format. This improved power consumption is almost equal to the power consumption of a same-sized LCD. The RGBW format is a promising technique for the further reduction of the power consumption of a full-color AMOLED.

  13. USE OF COAL DRYING TO REDUCE WATER CONSUMED IN PULVERIZED COAL POWER PLANTS

    SciTech Connect

    Edward Levy; Nenad Sarunac; Harun Bilirgen; Wei Zhang

    2005-04-01

    This is the ninth Quarterly Report for this project. The background and technical justification for the project are described, including potential benefits of reducing fuel moisture using power plant waste heat, prior to firing the coal in a pulverized coal boiler. During this last Quarter, comparative analyses were performed for lignite and PRB coals to determine how unit performance varies with coal product moisture. Results are given showing how the coal product moisture level and coal rank affect parameters such as boiler efficiency, station service power needed for fans and pulverizers and net unit heat rate. Results are also given for the effects of coal drying on cooling tower makeup water and comparisons are made between makeup water savings for various times of the year.

  14. Interpersonal multisensory stimulation reduces the overwhelming distracting power of self-gaze: psychophysical evidence for 'engazement'.

    PubMed

    Porciello, Giuseppina; Holmes, Brittany Serra; Liuzza, Marco Tullio; Crostella, Filippo; Aglioti, Salvatore Maria; Bufalari, Ilaria

    2014-01-01

    One's own face and gaze are never seen directly but only in a mirror. Yet, these stimuli capture attention more powerfully than others' face and gaze, suggesting the self is special for brain and behavior. Synchronous touches felt on one's own and seen on the face of others induce the sensation of including others in one's own face (enfacement). We demonstrate that enfacement may also reduce the overwhelming distracting power of self-gaze. This effect, hereafter called 'engazement', depends on the perceived physical attractiveness and inner beauty of the pair partner. Thus, we highlight for the first time the close link between enfacement and engazement by showing that changes of the self-face representation induced by facial visuo-tactile stimulation extend to gaze following, a separate process likely underpinned by different neural substrates. Moreover, although gaze following is a largely automatic, engazement is penetrable to the influence of social variables, such as positive interpersonal perception. PMID:25327255

  15. The use of combined heat and power (CHP) to reduce greenhouse gas emissions

    SciTech Connect

    Asrael, J.; Milmoe, P.H.; Haydel, J.

    1999-07-01

    Cogeneration or Combined Heat and Power (CHP) is the sequential production of electric power and thermal energy. It is a more efficient way of providing electricity and process heat than producing them independently. Average overall efficiencies can range from 70% to more than 80%. CHP decisions often present an opportunity to switch to a cleaner fuel. CHP systems are an attractive opportunity to save money, increase overall efficiency, reduce net emissions, and improve environmental performance. Climate Wise, a US Environmental Protection Agency (US EPA) program helping industrial Partners turn energy efficiency and pollution prevention into a corporate asset, has increased awareness of CHP by providing implementation and savings information, providing peer exchange opportunities for its Partners, and recognizing the achievements of Partners that have implemented CHP at their facilities. This paper profiles Climate Wise Partners that have invested in CHP systems, including describing how CHP is used in their facilities and the resulting cost and emission reductions.

  16. Wing-wake interaction reduces power consumption in insect tandem wings

    NASA Astrophysics Data System (ADS)

    Lehmann, Fritz-Olaf

    Insects are capable of a remarkable diversity of flight techniques. Dragonflies, in particular, are notable for their powerful aerial manoeuvres and endurance during prey catching or territory flights. While most insects such as flies, bees and wasps either reduced their hinds wings or mechanically coupled fore and hind wings, dragonflies have maintained two independent-controlled pairs of wings throughout their evolution. An extraordinary feature of dragonfly wing kinematics is wing phasing, the shift in flapping phase between the fore and hind wing periods. Wing phasing has previously been associated with an increase in thrust production, readiness for manoeuvrability and hunting performance. Recent studies have shown that wing phasing in tandem wings produces a twofold modulation in hind wing lift, but slightly reduces the maximum combined lift of fore and hind wings, compared to two wings flapping in isolation. Despite this disadvantage, however, wing phasing is effective in improving aerodynamic efficiency during flight by the removal of kinetic energy from the wake. Computational analyses demonstrate that this increase in flight efficiency may save up to 22% aerodynamic power expenditure compared to insects flapping only two wings. In terms of engineering, energetic benefits in four-wing flapping are of substantial interest in the field of biomimetic aircraft design, because the performance of man-made air vehicles is often limited by high-power expenditure rather than by lift production. This manuscript provides a summary on power expenditures and aerodynamic efficiency in flapping tandem wings by investigating wing phasing in a dynamically scaled robotic model of a hovering dragonfly.

  17. Wing-wake interaction reduces power consumption in insect tandem wings

    NASA Astrophysics Data System (ADS)

    Lehmann, Fritz-Olaf

    2009-05-01

    Insects are capable of a remarkable diversity of flight techniques. Dragonflies, in particular, are notable for their powerful aerial manoeuvres and endurance during prey catching or territory flights. While most insects such as flies, bees and wasps either reduced their hinds wings or mechanically coupled fore and hind wings, dragonflies have maintained two independent-controlled pairs of wings throughout their evolution. An extraordinary feature of dragonfly wing kinematics is wing phasing, the shift in flapping phase between the fore and hind wing periods. Wing phasing has previously been associated with an increase in thrust production, readiness for manoeuvrability and hunting performance. Recent studies have shown that wing phasing in tandem wings produces a twofold modulation in hind wing lift, but slightly reduces the maximum combined lift of fore and hind wings, compared to two wings flapping in isolation. Despite this disadvantage, however, wing phasing is effective in improving aerodynamic efficiency during flight by the removal of kinetic energy from the wake. Computational analyses demonstrate that this increase in flight efficiency may save up to 22% aerodynamic power expenditure compared to insects flapping only two wings. In terms of engineering, energetic benefits in four-wing flapping are of substantial interest in the field of biomimetic aircraft design, because the performance of man-made air vehicles is often limited by high-power expenditure rather than by lift production. This manuscript provides a summary on power expenditures and aerodynamic efficiency in flapping tandem wings by investigating wing phasing in a dynamically scaled robotic model of a hovering dragonfly.

  18. Reducing resistance training volume during Ramadan improves muscle strength and power in football players.

    PubMed

    Rebaï, H; Chtourou, H; Zarrouk, N; Harzallah, A; Kanoun, I; Dogui, M; Souissi, N; Tabka, Z

    2014-05-01

    We aimed to examine the effect of maintaining or reducing resistance training volume during Ramadan-intermittent-fasting (RIF) on short-term maximal performances. 20 footballers (age: 18.4 ± 0.8 years; body-mass: 72.4 ± 4.1 kg; height: 183.4 ± 4.6 cm) were matched and randomly assigned to a normal-training-group (G1) or a tapering-group (G2). They were tested for muscular strength (maximal-voluntary-contraction) and power (squat-jump and counter-movement-jump) 1 month before RIF (T0), 1 week before RIF (T1), after 2 weeks of fasting (T2) and at the end of RIF (T3). From T1 to T2, subjects performed a whole-body resistance training program (8-repetitions × 4-sets with 4-min recovery in-between). During RIF, G1 maintained the same training program, while G2 performed a period of reduced training volume (3 sets/exercise; - 22%). Muscle strength and power increased significantly from T0 to T1, from T0 to T2 and from T0 to T3 in G1 and G2 and from T1 to T2 and from T1 to T3 only in G2 (p<0.05). Performance was higher in G2 than G1 during T2 (p<0.01). Moreover, the ∆-change of performance between T0 and T2 and T3 was significantly higher in G2 than G1 (p<0.05). For young soccer players, a tapering period characterized by a reduced training volume during RIF may lead to significant improvement in muscle strength and power. PMID:24048913

  19. Optimal testing input sets for reduced diagnosis time of nuclear power plant digital electronic circuits

    SciTech Connect

    Kim, D.S.; Seong, P.H. . Dept. of Nuclear Engineering)

    1994-02-01

    This paper describes the optimal testing input sets required for the fault diagnosis of the nuclear power plant digital electronic circuits. With the complicated systems such as very large scale integration (VLSI), nuclear power plant (NPP), and aircraft, testing is the major factor of the maintenance of the system. Particularly, diagnosis time grows quickly with the complexity of the component. In this research, for reduce diagnosis time the authors derived the optimal testing sets that are the minimal testing sets required for detecting the failure and for locating of the failed component. For reduced diagnosis time, the technique presented by Hayes fits best for the approach to testing sets generation among many conventional methods. However, this method has the following disadvantages: (a) it considers only the simple network (b) it concerns only whether the system is in failed state or not and does not provide the way to locate the failed component. Therefore the authors have derived the optimal testing input sets that resolve these problems by Hayes while preserving its advantages. When they applied the optimal testing sets to the automatic fault diagnosis system (AFDS) which incorporates the advanced fault diagnosis method of artificial intelligence technique, they found that the fault diagnosis using the optimal testing sets makes testing the digital electronic circuits much faster than that using exhaustive testing input sets; when they applied them to test the Universal (UV) Card which is a nuclear power plant digital input/output solid state protection system card, they reduced the testing time up to about 100 times.

  20. Ischemic preconditioning reduces hemodynamic response during metaboreflex activation.

    PubMed

    Mulliri, Gabriele; Sainas, Gianmarco; Magnani, Sara; Palazzolo, Girolamo; Milia, Nicola; Orrù, Andrea; Roberto, Silvana; Marongiu, Elisabetta; Milia, Raffaele; Crisafulli, Antonio

    2016-05-01

    Ischemic preconditioning (IP) has been shown to improve exercise performance and to delay fatigue. However, the precise mechanisms through which IP operates remain elusive. It has been hypothesized that IP lowers the sensation of fatigue by reducing the discharge of group III and IV nerve endings, which also regulate hemodynamics during the metaboreflex. We hypothesized that IP reduces the blood pressure response during the metaboreflex. Fourteen healthy males (age between 25 and 48 yr) participated in this study. They underwent the following randomly assigned protocol: postexercise muscle ischemia (PEMI) test, during which the metaboreflex was elicited after dynamic handgrip; control exercise recovery session (CER) test; and PEMI after IP (IP-PEMI) test. IP was obtained by occluding forearm circulation for three cycles of 5 min spaced by 5 min of reperfusion. Hemodynamics were evaluated by echocardiography and impedance cardiography. The main results were that after IP the mean arterial pressure response was reduced compared with the PEMI test (means ± SD +3.37 ± 6.41 vs. +9.16 ± 7.09 mmHg, respectively). This was the consequence of an impaired venous return that impaired the stroke volume during the IP-PEMI more than during the PEMI test (-1.43 ± 15.35 vs. +10.28 ± 10.479 ml, respectively). It was concluded that during the metaboreflex, IP affects hemodynamics mainly because it impairs the capacity to augment venous return and to recruit the cardiac preload reserve. It was hypothesized that this is the consequence of an increased nitric oxide production, which reduces the possibility to constrict venous capacity vessels. PMID:26936782

  1. Sensory stimuli reduce the dimensionality of cortical activity

    NASA Astrophysics Data System (ADS)

    Mazzucato, Luca; Fontanini, Alfredo; La Camera, Giancarlo

    Neural ensembles in alert animals generate complex patterns of activity. Although cortical activity unfolds in a space whose dimension is equal to the number of neurons, it is often restricted to a lower dimensional subspace. Dimensionality is the minimal number of dimensions that accurately capture neural dynamics, and may be related to the computational tasks supported by the neural circuit. Here, we investigate the dimensionality of neural ensembles from the insular cortex of alert rats during periods of `ongoing' (spontaneous) and stimulus-evoked activity. We find that the dimensionality grows with ensemble size, and does so significantly faster during ongoing compared to evoked activity. We explain both results using a recurrent spiking network with clustered architecture, and obtain analytical results on the dependence of dimensionality on ensemble size, number of clusters, and pair-wise noise correlations. The theory predicts a characteristic scaling with ensemble size and the existence of an upper bound on dimensionality, which grows with the number of clusters and decreases with the amount of noise correlations. To our knowledge, this is the first mechanistic model of neural dimensionality in cortex during both spontaneous and evoked activity.

  2. NGNP/HTE full-power operation at reduced high-temperature heat exchanger temperatures.

    SciTech Connect

    VIlim, R.; Nuclear Engineering Division

    2009-03-12

    Operation of the Next Generation Nuclear Plant (NGNP) with reduced reactor outlet temperature at full power was investigated for the High Temperature Electrolysis (HTE) hydrogen-production application. The foremost challenge for operation at design temperature is achieving an acceptably long service life for heat exchangers. In both the Intermediate Heat Exchanger (IHX) and the Process Heat Exchanger (PHX) (referred to collectively as high temperature heat exchangers) a pressure differential of several MPa exists with temperatures at or above 850 C. Thermal creep of the heat exchanger channel wall may severely limit heat exchanger life depending on the alloy selected. This report investigates plant performance with IHX temperatures reduced by lowering reactor outlet temperature. The objective is to lower the temperature in heat transfer channels to the point where existing materials can meet the 40 year lifetime needed for this component. A conservative estimate for this temperature is believed to be about 700 C. The reactor outlet temperature was reduced from 850 C to 700 C while maintaining reactor power at 600 MWt and high pressure compressor outlet at 7 MPa. We included a previously reported design option for reducing temperature at the PHX. Heat exchanger lengths were adjusted to reflect the change in performance resulting from coolant property changes and from resizing related to operating-point change. Turbomachine parameters were also optimized for the new operating condition. An integrated optimization of the complete system including heat transfer equipment was not performed. It is estimated, however, that by performing a pinch analysis the combined plant efficiency can be increased from 35.5 percent obtained in this report to a value between 38.5 and 40.1 percent. Then after normalizing for a more than three percent decrease in commodities inventory compared to the reference plant, the commodities-normalized efficiency lies between 40.0 and 41.3. This

  3. The particulate-related health benefits of reducing power plant emissions

    SciTech Connect

    Schneider, C.

    2000-10-01

    The report estimates the adverse human health effects due to exposure to particulate matter from power plants. Power plants are significant emitters of sulfur dioxide and nitrogen oxides. In many parts of the U.S., especially the Midwest, power plants are the largest contributors. These gases are harmful themselves, and they contribute to the formation of acid rain and particulate matter. Particulate matter reduces visibility, often producing a milky haze that blankets wide regions, and it is a serious public health problem. Over the past decade and more, numerous studies have linked particulate matter to a wide range of adverse health effects in people of all ages. Epidemiologists have consistently linked particulate matter with effects ranging from premature death, hospital admissions and asthma attacks to chronic bronchitis. This study documents the health impacts from power plant air pollution emissions. Using the best available emissions and air quality modeling programs, the stud y forecasts ambient air quality for a business-as-usual baseline scenario for 2007, assuming full implementation of the Acid Rain program and the U.S. Environmental Protection Agency's (EPA) Summer Smog rule (the 1999 NO{sub x} SIP Call). The study then estimates the attributable health impacts from all power plant emissions. Finally, the study estimates air quality for a specific policy alternative: reducing total power plant emissions of SO{sub 2} and NO{sub x} 75 percent form the levels emitted in 1997. The difference between this '75 percent reduction scenario' and the baseline provides an estimate of the health effects that would be avoided by this reduction in power plant emissions. In addition to the policy scenario, the work involved performing sensitivity analyses to examine alternative emission reductions and forecast ambient air quality using a second air quality model. EPA uses both air quality models extensively, and both suggest that power plants make a large

  4. Burnout Is Associated with Reduced Parasympathetic Activity and Reduced HPA Axis Responsiveness, Predominantly in Males

    PubMed Central

    de Vente, Wieke; van Amsterdam, Jan G. C.; Olff, Miranda; Kamphuis, Jan H.; Emmelkamp, Paul M. G.

    2015-01-01

    There is mounting evidence that burnout is a risk factor for cardiovascular disease (CVD). Stress-related dysregulation of the sympathetic and parasympathetic system and the hypothalamic pituitary adrenal (HPA) axis may explain the enhanced risk for CVD. To test this hypothesis, 55 patients (34 males and 21 females) with burnout on sickness absence and 40 healthy participants (16 males and 24 females) were exposed to a psychosocial stressor consisting of mental arithmetic and public speech. Physiological variables (i.e., blood pressure, heart rate, cardiac output, vascular resistance, cortisol, and alpha-amylase) were measured. Basal levels, reactivity, and recovery were compared between groups. In male patients, baseline systolic blood pressure was higher, whereas basal alpha-amylase and cortisol reactivity were lower than in healthy males. In female patients, a tendency for lower basal cortisol was found as compared to healthy females. Furthermore, reduced basal heart rate variability and a trend for elevated basal cardiac output were observed in both male and female patients. Burnout is characterised by dysregulation of the sympathetic and parasympathetic system and the HPA axis, which was more pronounced in males than in females. This study further supports burnout as being a risk factor for CVD through dysregulation of the sympathetic and parasympathetic system and the HPA axis. PMID:26557670

  5. Space Power Amplification with Active Linearly Tapered Slot Antenna Array

    NASA Technical Reports Server (NTRS)

    Simons, Rainee N.; Lee, Richard Q.

    1993-01-01

    A space power amplifier composed of active linearly tapered slot antennas (LTSA's) has been demonstrated and shown to have a gain of 30 dB at 20 GHz. In each of the antenna elements, a GaAs monolithic microwave integrated circuit (MMIC) three-stage power amplifier is integrated with two LTSA's. The LTSA and the MMIC power amplifier has a gain of 11 dB and power added efficiency of 14 percent respectively. The design is suitable for constructing a large array using monolithic integration techniques.

  6. Reduced Frontal Activation with Increasing 2nd Language Proficiency

    ERIC Educational Resources Information Center

    Stein, Maria; Federspiel, Andrea; Koenig, Thomas; Wirth, Miranka; Lehmann, Christoph; Wiest, Roland; Strik, Werner; Brandeis, Daniel; Dierks, Thomas

    2009-01-01

    The factors influencing the degree of separation or overlap in the neuronal networks responsible for the processing of first and second language are still subject to investigation. This longitudinal study investigates how increasing second language proficiency influences activation differences during lexico-semantic processing of first and second…

  7. Methodology for Constructing Reduced-Order Power Block Performance Models for CSP Applications: Preprint

    SciTech Connect

    Wagner, M.

    2010-10-01

    The inherent variability of the solar resource presents a unique challenge for CSP systems. Incident solar irradiation can fluctuate widely over a short time scale, but plant performance must be assessed for long time periods. As a result, annual simulations with hourly (or sub-hourly) timesteps are the norm in CSP analysis. A highly detailed power cycle model provides accuracy but tends to suffer from prohibitively long run-times; alternatively, simplified empirical models can run quickly but don?t always provide enough information, accuracy, or flexibility for the modeler. The ideal model for feasibility-level analysis incorporates both the detail and accuracy of a first-principle model with the low computational load of a regression model. The work presented in this paper proposes a methodology for organizing and extracting information from the performance output of a detailed model, then using it to develop a flexible reduced-order regression model in a systematic and structured way. A similar but less generalized approach for characterizing power cycle performance and a reduced-order modeling methodology for CFD analysis of heat transfer from electronic devices have been presented. This paper builds on these publications and the non-dimensional approach originally described.

  8. Efforts to Reduce the Impacts of Hydroelectric Power Production on Reservoir Fisheries in the United States.

    SciTech Connect

    Cada, G. F.

    1997-09-08

    Research into the environmental effects of hydroelectric power production in the United States has focused increasingly on resident and migratory fish populations. Hydropower dams and reservoirs can block fish movements in both upstream and downstream directions. These movements are essential for important stocks of anadromous and catadromous fish. In addition, some strictly freshwater fish may move long distances within a river during their life cycle.A dam can pose an impassable barrier for fish trying to move upstream unless mitigation measures in the form of ladders or lifts are provided. Fish moving downstream to the sea may become disoriented when they encounter static water within a reservoir. Both resident and migratory fish may be injured or killed by passing through the turbine or over the spillway. In the United States, a variety of organizations conduct applied research and development of measures to (1) enhance fish passage, (2) reduce the numbers of fish that are drawn into the turbine intakes, and (3) reduce the injury and mortality rates of fish that pass through the turbines. Examples of these efforts from a variety of river systems and hydroelectric power plants are described.

  9. Active high-power RF switch and pulse compression system

    DOEpatents

    Tantawi, Sami G.; Ruth, Ronald D.; Zolotorev, Max

    1998-01-01

    A high-power RF switching device employs a semiconductor wafer positioned in the third port of a three-port RF device. A controllable source of directed energy, such as a suitable laser or electron beam, is aimed at the semiconductor material. When the source is turned on, the energy incident on the wafer induces an electron-hole plasma layer on the wafer, changing the wafer's dielectric constant, turning the third port into a termination for incident RF signals, and. causing all incident RF signals to be reflected from the surface of the wafer. The propagation constant of RF signals through port 3, therefore, can be changed by controlling the beam. By making the RF coupling to the third port as small as necessary, one can reduce the peak electric field on the unexcited silicon surface for any level of input power from port 1, thereby reducing risk of damaging the wafer by RF with high peak power. The switch is useful to the construction of an improved pulse compression system to boost the peak power of microwave tubes driving linear accelerators. In this application, the high-power RF switch is placed at the coupling iris between the charging waveguide and the resonant storage line of a pulse compression system. This optically controlled high power RF pulse compression system can handle hundreds of Megawatts of power at X-band.

  10. T Lymphocyte Activation Threshold is Increased in Reduced Gravity

    NASA Technical Reports Server (NTRS)

    Adams, Charley L.; Gonzalez, M.; Sams, C. F.

    2000-01-01

    There have been substantial advances in molecular and cellular biology that have provided new insight into the biochemical and genetic basis of lymphocyte recognition, activation and expression of distinct functional phenotypes. It has now become evident that for both T and B cells, stimuli delivered through their receptors can result in either clonal expansion or apoptosis. In the case of T cells, clonal expansion of helper cells is accompanied by differentiation into two major functional subsets which regulate the immune response. The pathways between the membrane and the nucleus and their molecular components are an area of very active investigation. This meeting will draw together scientists working on diverse aspects of this problem, including receptor ligand interactions, intracellular pathways that transmit receptor mediated signals and the effect of such signal transduction pathways on gene regulation. The aim of this meeting is to integrate the information from these various experimental approaches into a new synthesis and molecular explanation of T cell activation, differentiation and death.

  11. Standardization of the reducing power of zero-valent iron using iodine.

    PubMed

    Kim, Heonki; Yang, Haewon; Kim, Juyoung

    2014-01-01

    Because iron-based materials that are used for the permeable reactive barrier systems come in various shapes, sizes, and with various surface properties depending on the manufacturing sources, their reductive powers vary in a wide spectrum. A new experimental procedure to evaluate the reductive power of iron material was developed in this study. Tri-iodide (I3(-)) was used as the representative oxidizing agent that reacts with zero-valent iron (ZVI). Three iron-based materials (two scraps, two powders) and four chlorinated chemicals [perchloroethene (PCE), trichloroethene (TCE), 1,1,1-trichloroethane (TCA), and pentachlorophenol (PCP)] were used in this study. Redox reactions were conducted in glass vials containing aqueous solutions of chlorinated compounds or tri-iodide with known masses of iron material. After a predetermined reaction time each vial was opened and the solution was analyzed for the concentration of reduced compound. The apparent rate contant (k(i)(obs)) of iodine reduction reaction with ZVIs was found to be proportional to that (k(c)(obs)) of chlorinated contaminant. The surface area-normalized reduction rate constants (k(c)(nor)) for contaminants and tri-iodide (k(i)(nor)) were also proportional to each other. The ratio of rate constants, K(nor) (= k(c)(nor)/k(i)(nor)) was estimated for each contaminant; 3.29 × 10(-7), 5.86 × 10(-7), 6.70 × 10(-7), and 7.87 × 10(-10) M, for PCE, TCE, TCA, and PCP, respectively. The results of this study suggest that the reductive power of ZVI materials can be standardized using tri-iodide, and thus, can provide a good reference for the quantitative assessment of the reactivity of metallic reducing agents of environmental interest including ZVIs. PMID:24410682

  12. Textured bearing surface in artificial joints to reduce macrophage activation

    NASA Astrophysics Data System (ADS)

    Nakanishi, Yoshitaka; Nishi, Naoki; Chikaura, Hiroto; Nakashima, Yuta; Miura, Hiromasa; Higaki, Hidehiko; Mizuta, Hiroshi; Iwamoto, Yukihide; Fujiwara, Yukio; Komohara, Yoshihiro; Takeya, Motohiro

    2015-12-01

    Micro slurry-jet erosion has been proposed as a precision machining technique for the bearing surfaces of artificial joints in order to reduce the total amount of polyethylene wear and to enlarge the size of the wear debris. The micro slurry-jet erosion method is a wet blasting technique which uses alumina particles as the abrasive medium along with compressed air and water to create an ideal surface. Pin-on-disc wear tests with multidirectional sliding motion on the textured surface of a \\text{Co}-\\text{Cr}-\\text{Mo} alloy counterface for polyethylene resulted in both a reduction of wear as well as enlargement of the polyethylene debris size. In this study, primary human peripheral blood mononuclear phagocytes were incubated with the debris, and it was elucidated that the wear debris generated on the textured surface regulated secretion of the proinflammatory cytokines IL-6 and TNF-α, indicating a reduction in the induced tissue reaction and joint loosening.

  13. Myostatin Attenuation In Vivo Reduces Adiposity, but Activates Adipogenesis.

    PubMed

    Li, Naisi; Yang, Qiyuan; Walker, Ryan G; Thompson, Thomas B; Du, Min; Rodgers, Buel D

    2016-01-01

    A potentially novel approach for treating obesity includes attenuating myostatin as this increases muscle mass and decreases fat mass. Notwithstanding, conflicting studies report that myostatin stimulates or inhibits adipogenesis and it is unknown whether reduced adiposity with myostatin attenuation results from changes in fat deposition or adipogenesis. We therefore quantified changes in the stem, transit amplifying and progenitor cell pool in white adipose tissue (WAT) and brown adipose tissue (BAT) using label-retaining wild-type and mstn(-/-) (Jekyll) mice. Muscle mass was larger in Jekyll mice, WAT and BAT mass was smaller and label induction was equal in all tissues from both wild-type and Jekyll mice. The number of label-retaining cells, however, dissipated quicker in WAT and BAT of Jekyll mice and was only 25% and 17%, respectively, of wild-type cell counts 1 month after induction. Adipose cell density was significantly higher in Jekyll mice and increased over time concomitant with label-retaining cell disappearance, which is consistent with enhanced expansion and differentiation of the stem, transit amplifying and progenitor pool. Stromal vascular cells from Jekyll WAT and BAT differentiated into mature adipocytes at a faster rate than wild-type cells and although Jekyll WAT cells also proliferated quicker in vitro, those from BAT did not. Differentiation marker expression in vitro, however, suggests that mstn(-/-) BAT preadipocytes are far more sensitive to the suppressive effects of myostatin. These results suggest that myostatin attenuation stimulates adipogenesis in vivo and that the reduced adiposity in mstn(-/-) animals results from nutrient partitioning away from fat and in support of muscle. PMID:26580671

  14. Barriers associated with reduced physical activity in COPD patients*

    PubMed Central

    Amorim, Priscila Batista; Stelmach, Rafael; Carvalho, Celso Ricardo Fernandes; Fernandes, Frederico Leon Arrabal; Carvalho-Pinto, Regina Maria; Cukier, Alberto

    2014-01-01

    OBJECTIVE: To evaluate the ability of COPD patients to perform activities of daily living (ADL); to identify barriers that prevent these individuals from performing ADL; and to correlate those barriers with dyspnea severity, six-minute walk test (6MWT), and an ADL limitation score. METHODS: In COPD patients and healthy, age-matched controls, the number of steps, the distance walked, and walking time were recorded with a triaxial accelerometer, for seven consecutive days. A questionnaire regarding perceived barriers and the London Chest Activity of Daily Living (LCADL) scale were used in order to identify the factors that prevent the performance of ADL. The severity of dyspnea was assessed with two scales, whereas submaximal exercise capacity was determined on the basis of the 6MWT. RESULTS: We evaluated 40 COPD patients and 40 controls. In comparison with the control values, the mean walk time was significantly shorter for COPD patients (68.5 ± 25.8 min/day vs. 105.2 ± 49.4 min/day; p < 0.001), as was the distance walked (3.9 ± 1.9 km/day vs. 6.4 ± 3.2 km/day; p < 0.001). The COPD patients also walked fewer steps/day. The most common self-reported barriers to performing ADL were lack of infrastructure, social influences, and lack of willpower. The 6MWT distance correlated with the results obtained with the accelerometer but not with the LCADL scale results. CONCLUSIONS: Patients with COPD are less active than are healthy adults of a comparable age. Physical inactivity and the barriers to performing ADL have immediate implications for clinical practice, calling for early intervention measures. PMID:25410838

  15. Tensile and creep properties of reduced activation ferritic-martensitic steel for fusion energy application

    NASA Astrophysics Data System (ADS)

    Mathew, M. D.; Vanaja, J.; Laha, K.; Varaprasad Reddy, G.; Chandravathi, K. S.; Bhanu Sankara Rao, K.

    2011-10-01

    Tensile and creep properties of a reduced activation ferritic-martensitic (RAFM) steel for Indian Test Blanket Module (TBM) to be tested in ITER have been evaluated. The tensile strength was found to decrease with temperature; the rate of decrease being slower in the intermediate temperature range of 450-650 K. Tensile ductility of the steel decreased with increase in temperature up to 650 K, followed by a rapid increase beyond 650 K. Creep studies have been carried out at 773, 823 and 873 K over a stress range of 100-300 MPa. The variation of minimum creep rate with applied stress followed a power law, ɛ = Aσ n. The ' n' value decreased with increase in temperature. The creep rupture life was found to relate inversely with minimum creep rate through the Monkman-Grant relation, t r · ɛ = constant. The tensile and creep properties of the steel were comparable with those of Eurofer 97.

  16. Sequential Activation of a Segmented Ground Pad Reduces Skin Heating During Radiofrequency Tumor Ablation: Optimization via Computational Models

    PubMed Central

    Schutt, David J.; Haemmerich, Dieter

    2009-01-01

    Radiofrequency (RF) ablation has become an accepted treatment modality for unresectable tumors. The need for larger ablation zones has resulted in increased RF generator power. Skin burns due to ground pad heating are increasingly limiting further increases in generator power, and thus, ablation zone size. We investigated a method for reducing ground pad heating in which a commercial ground pad is segmented into multiple ground electrodes, with sequential activation of ground electrode subsets. We created finite-element method computer models of a commercial ground pad (14 × 23 cm) and compared normal operation of a standard pad to sequential activation of a segmented pad (two to five separate ground electrode segments). A constant current of 1 A was applied for 12 min in all simulations. Time periods during sequential activation simulations were adjusted to keep the leading edge temperatures at each ground electrode equal. The maximum temperature using standard activation of the commercial pad was 41.7 °C. For sequential activation of a segmented pad, the maximum temperature ranged from 39.3 °C (five segments) to 40.9 °C (two segments). Sequential activation of a segmented ground pad resulted in lower tissue temperatures. This method may reduce the incidence of ground pad burns and enable the use of higher power generators during RF tumor ablation. PMID:18595807

  17. Nature experience reduces rumination and subgenual prefrontal cortex activation

    PubMed Central

    Bratman, Gregory N.; Hamilton, J. Paul; Hahn, Kevin S.; Daily, Gretchen C.; Gross, James J.

    2015-01-01

    Urbanization has many benefits, but it also is associated with increased levels of mental illness, including depression. It has been suggested that decreased nature experience may help to explain the link between urbanization and mental illness. This suggestion is supported by a growing body of correlational and experimental evidence, which raises a further question: what mechanism(s) link decreased nature experience to the development of mental illness? One such mechanism might be the impact of nature exposure on rumination, a maladaptive pattern of self-referential thought that is associated with heightened risk for depression and other mental illnesses. We show in healthy participants that a brief nature experience, a 90-min walk in a natural setting, decreases both self-reported rumination and neural activity in the subgenual prefrontal cortex (sgPFC), whereas a 90-min walk in an urban setting has no such effects on self-reported rumination or neural activity. In other studies, the sgPFC has been associated with a self-focused behavioral withdrawal linked to rumination in both depressed and healthy individuals. This study reveals a pathway by which nature experience may improve mental well-being and suggests that accessible natural areas within urban contexts may be a critical resource for mental health in our rapidly urbanizing world. PMID:26124129

  18. Nature experience reduces rumination and subgenual prefrontal cortex activation.

    PubMed

    Bratman, Gregory N; Hamilton, J Paul; Hahn, Kevin S; Daily, Gretchen C; Gross, James J

    2015-07-14

    Urbanization has many benefits, but it also is associated with increased levels of mental illness, including depression. It has been suggested that decreased nature experience may help to explain the link between urbanization and mental illness. This suggestion is supported by a growing body of correlational and experimental evidence, which raises a further question: what mechanism(s) link decreased nature experience to the development of mental illness? One such mechanism might be the impact of nature exposure on rumination, a maladaptive pattern of self-referential thought that is associated with heightened risk for depression and other mental illnesses. We show in healthy participants that a brief nature experience, a 90-min walk in a natural setting, decreases both self-reported rumination and neural activity in the subgenual prefrontal cortex (sgPFC), whereas a 90-min walk in an urban setting has no such effects on self-reported rumination or neural activity. In other studies, the sgPFC has been associated with a self-focused behavioral withdrawal linked to rumination in both depressed and healthy individuals. This study reveals a pathway by which nature experience may improve mental well-being and suggests that accessible natural areas within urban contexts may be a critical resource for mental health in our rapidly urbanizing world. PMID:26124129

  19. AIDing cancer treatment: Reducing AID activity via HSP90 inhibition.

    PubMed

    Rebhandl, Stefan; Geisberger, Roland

    2015-08-01

    The activation induced deaminase (AID) catalyses the two key events underlying humoral adaptive immunity: class switch recombination and somatic hypermutation of antibody genes in B lymphocytes. AID accomplishes this task by directly deaminating cytosines within the genomic immunoglobulin locus, thereby triggering a complex mutagenic process eventually leading to improved effector function of antibodies. However, it has long been noticed that AID can be aberrantly expressed in cancer and that its activity is not absolutely restricted to antibody genes, as substantial genome-wide off-target mutations have been observed, which contribute to tumorigenesis and clonal evolution of AID-expressing malignancies. In this issue of the European Journal of Immunology, Montamat-Sicotte et al. [Eur. J. Immunol. 2015. 45: 2365-2376] investigate the feasibility and efficacy of in vivo inhibition of AID with HSP90 inhibitors in a mouse model of B-cell leukemia and in vitro with a human breast cancer cell line, thereby demonstrating that cancer patients may benefit from preventing noncanonical AID functions. PMID:26151367

  20. Mobile Phone Interventions to Increase Physical Activity and Reduce Weight

    PubMed Central

    Stephens, Janna; Allen, Jerilyn

    2013-01-01

    Objective This systematic review was conducted to determine user satisfaction and effectiveness of smartphone applications and text messaging interventions to promote weight reduction and physical activity. Methods Studies of smartphone applications and text messaging interventions related to the cardiovascular risk factors of physical inactivity and overweight/obesity published between January 2005 and August 2010 were eligible. Studies related to disease management were excluded. Study characteristics and results were gathered and synthesized. Results A total of 36 citations from CINAHL, EMBASE, MEDLINE, PsyclNFO, and PubMed were identified; 7 articles were eligible for inclusion. The most frequent outcome measured in the studies was change in the weight of participants (57%). More than half of the studies (71%) reported statistically significant results in at least 1 outcome of weight loss, physical activity, dietary intake, decreased body mass index, decreased waist circumference, sugar-sweetened beverage intake, screen time, and satisfaction or acceptability outcomes. Conclusions All of the technology interventions that were supported by education or an additional intervention demonstrated a beneficial impact of text messaging or smartphone application for reduction of physical inactivity and/or overweight/obesity. More rigorous trials that determine what parts of the technology or intervention are effective as well as establishment of cost-effectiveness are necessary for further evaluation of smartphone and text messaging interventions. PMID:22635061

  1. Reducing the power consumption in LTE-Advanced wireless access networks by a capacity based deployment tool

    NASA Astrophysics Data System (ADS)

    Deruyck, Margot; Joseph, Wout; Tanghe, Emmeric; Martens, Luc

    2014-09-01

    As both the bit rate required by applications on mobile devices and the number of those mobile devices are steadily growing, wireless access networks need to be expanded. As wireless networks also consume a lot of energy, it is important to develop energy-efficient wireless access networks in the near future. In this study, a capacity-based deployment tool for the design of energy-efficient wireless access networks is proposed. Capacity-based means that the network responds to the instantaneous bit rate requirements of the users active in the selected area. To the best of our knowledge, such a deployment tool for energy-efficient wireless access networks has never been presented before. This deployment tool is applied to a realistic case in Ghent, Belgium, to investigate three main functionalities incorporated in LTE-Advanced: carrier aggregation, heterogeneous deployments, and Multiple-Input Multiple-Output (MIMO). The results show that it is recommended to introduce femtocell base stations, supporting both MIMO and carrier aggregation, into the network (heterogeneous deployment) to reduce the network's power consumption. For the selected area and the assumptions made, this results in a power consumption reduction up to 70%. Introducing femtocell base stations without MIMO and carrier aggregation can already result in a significant power consumption reduction of 38%.

  2. Optical computing for application to reducing the thickness of high-power-composite lenses.

    PubMed

    Wu, Bo-Wen

    2014-10-10

    With the adoption of polycarbonate lens material for injection molding of greater accuracy and at lower costs, polycarbonate has become very suitable for mass production of more economical products, such as diving goggles. However, with increasing requirements for visual quality improvement, lenses need to have not only refractive function but also thickness and spherical aberration, which are gradually being taken more seriously. For a high-power-composite lens, meanwhile, the thickness cannot be substantially reduced, and there is also the issue of severe spherical aberration at the lens edges. In order to increase the added value of the product without changing the material, the present research applied the eye model and Taguchi experiment method, combined with design optimization for hyperbolic-aspherical lens, to significantly reduce the lens thickness by more than 30%, outperforming the average thickness reduction in general aspherical lens. The spherical aberration at the lens edges was also reduced effectively during the optimization process for the nonspherical lens. Prototypes made by super-finishing machines were among the results of the experiment. This new application can be used in making a large amount of injection molds to substantially increase the economic value of the product. PMID:25322434

  3. Catalytic combustion of dry carbon monoxide by external power activation

    NASA Astrophysics Data System (ADS)

    Treviño, C.; Prince, J. C.

    2000-03-01

    The catalytic combustion of dry carbon monoxide and air in a planar stagnation-point flow over a platinum foil with external power is studied in this paper. The reduced heterogeneous kinetics are modelled with the dissociative adsorption of the molecular oxygen and the non-dissociative adsorption of CO, together with a surface reaction of the Langmuir-Hinshelwood type and the desorption reaction of the adsorbed product, CO 2(s). The resulting governing equations have been numerically integrated and the whole S-shaped response curve has been obtained as a function of the mixture initial concentration. The critical conditions for the catalytic ignition and extinction are deduced using high activation energy asymptotics of the desorption kinetics of the most efficient adsorbed reactant, CO(s). We obtained a very good agreement between the numerical and asymptotic results for the ignition and extinction conditions. In general, the ignition process can be well modelled without reactant consumption, while extinction occurs in the partial diffusion-controlled regime, with a finite non-zero concentration of carbon monoxide close to the plate.

  4. Single-Phase Active Boost Rectifier with Power Factor Correction for Wireless Power Transfer Applications

    SciTech Connect

    Chinthavali, Madhu Sudhan; Onar, Omer C; Miller, John M; Tang, Lixin

    2013-01-01

    Wireless Power Transfer (WPT) technology is a novel research area in the charging technology that bridges utility and the automotive industries. There are various solutions that are currently being evaluated by several research teams to find the most efficient way to manage the power flow from the grid to the vehicle energy storage system. There are different control parameters that can be utilized to compensate for the change in the impedance. To understand the power flow through the system this paper presents a novel approach to the system model and the impact of different control parameters on the load power. The implementation of an active front-end rectifier on the grid side for power factor control and voltage boost capability for load power regulation is also discussed.

  5. Modelling precipitate distribution in reduced-activation steels

    NASA Astrophysics Data System (ADS)

    Gaude-Fugarolas, D.; de Carlan, Y.

    2008-02-01

    The microstructure and carbide distribution in two commercial creep resistant, low-activation, martensitic alloys (F82H and JLF-1) have been modelled using a thermo-kinetic calculation package. The microstructures after manufacturing and after long unstrained thermal aging treatments (13 500 h) at various temperatures (250, 400 and 550 °C), considered to be representative of service temperatures, have been considered. In all cases, the calculated carbide size distributions match in order of magnitude experimental measurements, although the shape of the distribution differs. The obtained results are more accurate for alloy F82H than for alloy JLF-1. Nevertheless, this work shows that it is possible to obtain realistic estimates of the microstructure evolution of creep resistant alloys in long thermal ageing treatments at service-like temperatures.

  6. Analysing domestic activity to reduce household energy consumption.

    PubMed

    Fréjus, Myriam; Guibourdenche, Julien

    2012-01-01

    This paper presents our reflections on the issue of behavioral change according to energy conservation constraints and on the status of sustainability in the design of ambient interactive systems at home. We point out how ergonomics contributes to the study of human factors underlying energy consumption. Relating to situated cognition and human computer interaction, our approach relies both on the ergonomic evaluation of feedback consumption displays and on the modeling of domestic activities in order to identify household concerns in real settings. We present empirical results to illustrate this global approach. The results of those studies allow the design of interactive systems: informative and pedagogical systems as well as pervasive and adaptive ambient systems. In our approach, sustainability is taken into account as a design criterion, as security could be, whereas the main design purpose is to aid households in their daily life in order to build a "sustainable situation". PMID:22316779

  7. Immune Activation Reduces Sperm Quality in the Great Tit

    PubMed Central

    Losdat, Sylvain; Richner, Heinz; Blount, Jonathan D.; Helfenstein, Fabrice

    2011-01-01

    Mounting an immune response against pathogens incurs costs to organisms by its effects on important life-history traits, such as reproductive investment and survival. As shown recently, immune activation produces large amounts of reactive species and is suggested to induce oxidative stress. Sperm are highly susceptible to oxidative stress, which can negatively impact sperm function and ultimately male fertilizing efficiency. Here we address the question as to whether mounting an immune response affects sperm quality through the damaging effects of oxidative stress. It has been demonstrated recently in birds that carotenoid-based ornaments can be reliable signals of a male's ability to protect sperm from oxidative damage. In a full-factorial design, we immune-challenged great tit males while simultaneously increasing their vitamin E availability, and assessed the effect on sperm quality and oxidative damage. We conducted this experiment in a natural population and tested the males' response to the experimental treatment in relation to their carotenoid-based breast coloration, a condition-dependent trait. Immune activation induced a steeper decline in sperm swimming velocity, thus highlighting the potential costs of an induced immune response on sperm competitive ability and fertilizing efficiency. We found sperm oxidative damage to be negatively correlated with sperm swimming velocity. However, blood resistance to a free-radical attack (a measure of somatic antioxidant capacity) as well as plasma and sperm levels of oxidative damage (lipid peroxidation) remained unaffected, thus suggesting that the observed effect did not arise through oxidative stress. Towards the end of their breeding cycle, swimming velocity of sperm of more intensely colored males was higher, which has important implications for the evolution of mate choice and multiple mating in females because females may accrue both direct and indirect benefits by mating with males having better quality sperm

  8. Photovoltaic solar system connected to the electric power grid operating as active power generator and reactive power compensator

    SciTech Connect

    Albuquerque, Fabio L.; Moraes, Adelio J.; Guimaraes, Geraldo C.; Sanhueza, Sergio M.R.; Vaz, Alexandre R.

    2010-07-15

    In the case of photovoltaic (PV) systems acting as distributed generation (DG) systems, the DC energy that is produced is fed to the grid through the power-conditioning unit (inverter). The majority of contemporary inverters used in DG systems are current source inverters (CSI) operating at unity power factor. If, however, we assume that voltage source inverters (VSI) can replace CSIs, we can generate reactive power proportionally to the remaining unused capacity at any given time. According to the theory of instantaneous power, the inverter reactive power can be regulated by changing the amplitude of its output voltage. In addition, the inverter active power can be adjusted by modifying the phase angle of its output voltage. Based on such theory, both the active power supply and the reactive power compensation (RPC) can be carried out simultaneously. When the insolation is weak or the PV modules are inoperative at night, the RPC feature of a PV system can still be used to improve the inverter utilisation factor. Some MATLAB simulation results are included here to show the feasibility of the method. (author)

  9. Power Subsystem for Extravehicular Activities for Exploration Missions

    NASA Technical Reports Server (NTRS)

    Manzo, Michelle

    2005-01-01

    The NASA Glenn Research Center has the responsibility to develop the next generation space suit power subsystem to support the Vision for Space Exploration. Various technology challenges exist in achieving extended duration missions as envisioned for future lunar and Mars mission scenarios. This paper presents an overview of ongoing development efforts undertaken at the Glenn Research Center in support of power subsystem development for future extravehicular activity systems.

  10. A high power active circulator using GaN MMIC power amplifiers

    NASA Astrophysics Data System (ADS)

    Liming, Gu; Wenquan, Che; Huang, Fan-Hsiu; Chiu, Hsien-Chin

    2014-11-01

    This paper presents a 2.4 GHz hybrid integrated active circulator consisting of three power amplifiers and three PCB-based Wilkinson power dividers. The power amplifiers were designed and fabricated in a standard 0.35-μm AlGaN/GaN HEMT technology, and combined with three traditional power dividers on FR4 using bonding wires. Due to the isolation of power dividers, the isolation between three ports is achieved; meanwhile, due to the unidirectional characteristics of the power amplifiers, the nonreciprocal transfer characteristic of the circulator is realized. The measured insertion gain of the proposed active circulator is about 2-2.7 dB at the center frequency of 2.4 GHz, the isolation between three ports is better than 20 dB over 1.2-3.4 GHz, and the output power of the designed active circulator achieves up to 20.1-21.2 dBm at the center frequency.

  11. Reducing Size, Weight, and Power (SWaP) of Perception Systems in Small Autonomous Aerial Systems

    NASA Technical Reports Server (NTRS)

    Jones, Kennie H.; Gross, Jason

    2014-01-01

    The objectives are to examine recent trends in the reduction of size, weight, and power (SWaP) requirements of sensor systems for environmental perception and to explore new technology that may overcome limitations in current systems. Improving perception systems to facilitate situation awareness is critical in the move to introduce increasing autonomy in aerial systems. Whether the autonomy is in the current state-of-the-art of increasing automation or is enabling cognitive decisions that facilitate adaptive behavior, collection of environmental information and fusion of that information into knowledge that can direct actuation is imperative to decisions resulting in appropriate behavior. Artificial sensory systems such as cameras, radar, LIDAR, and acoustic sensors have been in use on aircraft for many years but, due to the large size and weight of the airplane and electrical power made available through powerful engines, the SWaP requirements of these sensors was inconsequential. With the proliferation of Remote Piloted Vehicles (RPV), the trend is in significant reduction in SWaP of the vehicles. This requires at least an equivalent reduction in SWaP for the sensory systems. A survey of some currently available sensor systems and changing technology will reveal the trend toward reduction of SWaP of these systems and will predict future reductions. A new technology will be introduced that provides an example of a desirable new trend. A new device replaces multiple conventional sensory devices facilitating synchronization, localization, altimetry, collision avoidance, terrain mapping, and data communication in a single integrated, small form-factor, extremely lightweight, and low power device that it is practical for integration into small autonomous vehicles and can facilitate cooperative behavior. The technology is based on Ultra WideBand (UWB) radio using short pulses of energy rather than continuous sine waves. The characteristics of UWB yield several

  12. Ozone risk assessment for plants: central role of metabolism-dependent changes in reducing power.

    PubMed

    Dizengremel, Pierre; Le Thiec, Didier; Bagard, Matthieu; Jolivet, Yves

    2008-11-01

    The combination of stomatal-dependent ozone flux and total ascorbate level is currently presented as a correct indicator for determining the degree of sensitivity of plants to ozone. However, the large changes in carbon metabolism could play a central role in the strategy of the foliar cells in response to chronic ozone exposure, participating in the supply of reducing power and carbon skeletons for repair and detoxification, and modifying the stomatal mode of functioning. To reinforce the accuracy of the definition of the threshold for ozone risk assessment, it is proposed to also consider the redox pool (NAD(P)H), the ratio between carboxylases and the water use efficiency as indicators of the differential ozone tolerance of plants. PMID:18243452

  13. Optimizing Technology to Reduce Mercury and Acid Gas Emissions from Electric Power Plants

    SciTech Connect

    Jeffrey C. Quick; David E. Tabet; Sharon Wakefield; Roger L. Bon

    2005-01-31

    Revised maps and associated data show potential mercury, sulfur, and chlorine emissions for U.S. coal by county of origin. Existing coal mining and coal washing practices result in a 25% reduction of mercury in U.S. coal before it is delivered to the power plant. Selection of low-mercury coal is a good mercury control option for plants having hot-side ESP, cold-side ESP, or hot-side ESP/FGD emission controls. Chlorine content is more important for plants having cold-side ESP/FGD or SDA/FF controls; optimum net mercury capture is indicated where chlorine is between 500 and 1000 ppm. Selection of low-sulfur coal should improve mercury capture where carbon in fly ash is used to reduce mercury emissions.

  14. USE OF COAL DRYING TO REDUCE WATER CONSUMED IN PULVERIZED COAL POWER PLANTS

    SciTech Connect

    Edward K. Levy; Nenad Sarunac; Gu Feng; Wei Zhang

    2004-04-01

    This is the fifth Quarterly Report for this project. The background and technical justification for the project are described, including potential benefits of reducing fuel moisture, prior to firing in a pulverized coal boiler. A theoretical model, for computing the effects of dryer design and operating conditions on performance of a continuous flow fluidized bed dryer, operating at steady state conditions, is described. Numerical results from the model, compared to data from a pilot scale lignite dryer located at Great River Energy's Coal Creek Station, show good agreement. The dryer model was used to perform parametric calculations on the effects of dryer design and operating conditions on dryer performance and required in-bed heat transfer. Other analyses show the first order effects of firing lignite and PRB coals, dried to various moisture levels, on flow rates of coal, combustion air and flue gas, fan and mill power and unit heat rate.

  15. A performance standards approach to reducing CO{sub 2} emissions from electric power plants

    SciTech Connect

    Rubin, E.S.

    2009-06-15

    The CO{sub 2} emission performance standard policies outlined in this paper could complement a cap-and-trade program that puts a price on carbon and serve to significantly reduce the CO{sub 2} emissions from coal use for electricity generation. Emission performance standards have a long history in the United States and have been successfully used to control emissions of various air pollutants from electric generators. This paper explores the rationale for using emission performance standards and describes the various types of performance standard policies. Emission performance standards that address CO{sub 2} emissions could promote the deployment of carbon capture and storage technology coupled with new and existing coal-fueled electric power plants. 28 refs., 4 figs., 4 tabs.

  16. Optimal active power dispatch by network flow approach

    SciTech Connect

    Carvalho, M.F. ); Soares, S.; Ohishi, T. )

    1988-11-01

    In this paper the optimal active power dispatch problem is formulated as a nonlinear capacitated network flow problem with additional linear constraints. Transmission flow limits and both Kirchhoff's laws are taken into account. The problem is solved by a Generalized Upper Bounding technique that takes advantage of the network flow structure of the problem. The new approach has potential applications on power systems problems such as economic dispatch, load supplying capability, minimum load shedding, and generation-transmission reliability. The paper also reviews the use of transportation models for power system analysis. A detailed illustrative example is presented.

  17. Gamma power is phase-locked to posterior alpha activity.

    PubMed

    Osipova, Daria; Hermes, Dora; Jensen, Ole

    2008-01-01

    Neuronal oscillations in various frequency bands have been reported in numerous studies in both humans and animals. While it is obvious that these oscillations play an important role in cognitive processing, it remains unclear how oscillations in various frequency bands interact. In this study we have investigated phase to power locking in MEG activity of healthy human subjects at rest with their eyes closed. To examine cross-frequency coupling, we have computed coherence between the time course of the power in a given frequency band and the signal itself within every channel. The time-course of the power was calculated using a sliding tapered time window followed by a Fourier transform. Our findings show that high-frequency gamma power (30-70 Hz) is phase-locked to alpha oscillations (8-13 Hz) in the ongoing MEG signals. The topography of the coupling was similar to the topography of the alpha power and was strongest over occipital areas. Interestingly, gamma activity per se was not evident in the power spectra and only became detectable when studied in relation to the alpha phase. Intracranial data from an epileptic subject confirmed these findings albeit there was slowing in both the alpha and gamma band. A tentative explanation for this phenomenon is that the visual system is inhibited during most of the alpha cycle whereas a burst of gamma activity at a specific alpha phase (e.g. at troughs) reflects a window of excitability. PMID:19098986

  18. Forward Modeling of Reduced Power Spectra from Three-dimensional k-space

    NASA Astrophysics Data System (ADS)

    von Papen, Michael; Saur, Joachim

    2015-06-01

    We present results from a numerical forward model to evaluate one-dimensional reduced power spectral densities (PSDs) from arbitrary energy distributions in {\\boldsymbol{k}} -space. In this model, we can separately calculate the diagonal elements of the spectral tensor for incompressible axisymmetric turbulence with vanishing helicity. Given a critically balanced turbulent cascade with {{k}\\parallel }∼ k\\bot α and α \\lt 1, we explore the implications on the reduced PSD as a function of frequency. The spectra are obtained under the assumption of Taylor’s hypothesis. We further investigate the functional dependence of the spectral index κ on the field-to-flow angle θ between plasma flow and background magnetic field from MHD to electron kinetic scales. We show that critically balanced turbulence asymptotically develops toward θ-independent spectra with a slope corresponding to the perpendicular cascade. This occurs at a transition frequency {{f}2D}(L,α ,θ ), which is analytically estimated and depends on outer scale L, critical balance exponent α, and field-to-flow angle θ. We discuss anisotropic damping terms acting on the {\\boldsymbol{k}} -space distribution of energy and their effects on the PSD. Further, we show that the spectral anisotropies κ (θ ) as found by Horbury et al. and Chen et al. in the solar wind are in accordance with a damped critically balanced cascade of kinetic Alfvén waves. We also model power spectra obtained by Papen et al. in Saturn’s plasma sheet and find that the change of spectral indices inside 9 {{R}s} can be explained by damping on electron scales.

  19. Trapping of redox-mediators at the surface of Chlorella vulgaris leads to error in measurements of cell reducing power.

    PubMed

    Thorne, Rebecca J; Hu, Huaining; Schneider, Kenneth; Cameron, Petra J

    2014-03-28

    The reduction of the redox mediator ferricyanide, [Fe(CN)6](3-), by a range of algal and bacterial species, is frequently measured to probe plasma membrane ferrireductase activity or to quantify the reducing power of algal/bacterial biofilms and suspensions. In this study we have used rotating disk electrochemistry (RDE) to investigate the reduction of ferricyanide by the model organism Chlorella vulgaris. Importantly, we have seen that the diffusion limited current due to the oxidation of ferrocyanide, [Fe(CN)6](4-), at the electrode decreased linearly as C. vulgaris was added to the solution, even though in a pure ferrocyanide solution the algae are not able to reduce the mediator further and are simply spectator 'particles'. We attribute this effect to trapping of ferrocyanide at the cell surface, with up to 14% of the ferrocyanide missing from the solution at the highest cell concentration. The result has important implications for all techniques that use electrochemistry and other concentration dependent assays (e.g. fluorescence and colourimetry) to monitor ferrocyanide concentrations in the presence of both biofilms and cell suspensions. Analyte trapping could lead to a substantial underestimation of the concentration of reduced product. PMID:24535230

  20. Reducing the Risk of Damage to Power Transformers of 110 kV and Above Accompanying Internal Short Circuits

    SciTech Connect

    L’vova, M. M.; L’vov, S. Yu.; Komarov, V. B.; Lyut’ko, E. O.; Vdoviko, V. P.; Demchenko, V. V.; Belyaev, S. G.; Savel’ev, V. A.; L’vov, M. Yu. L’vov, Yu. N.

    2015-03-15

    Methods of increasing the operating reliability of power transformers, autotransformers and shunting reactors in order to reduce the risk of damage, which accompany internal short circuits and equipment fires and explosions, are considered.

  1. Multi-coil approach to reduce electromagnetic energy absorption for wirelessly powered implants.

    PubMed

    RamRakhyani, Anil Kumar; Lazzi, Gianluca

    2014-01-01

    Near-field inductive coupling is a commonly used technique for wireless power transfer (WPT) in biomedical implants. Owing to the close proximity of the implant coil(s) with the tissue ( ∼1 mm) and high current ( ∼100-300 mA) in the magnetic coil(s), a significant induced electric field can be generated for the operating frequency (1-20 MHz). In this Letter, a multi-coil-based WPT technique is proposed to selectively control the currents in the external and implant coils to reduce the specific absorption rate (SAR). A three-coil WPT system, that can achieve 26% reduction in peak 1-g SAR and 15% reduction in peak 10-g SAR, as compared to a two-coil WPT system with the same dimensions, is implemented and used to demonstrate the effectiveness of the proposed approach. To achieve the seamless design for the external and implant electronics, the multi-coil system achieves the same voltage gain and bandwidth as the two-coil design with 46% improvement in the power transfer efficiency. PMID:26609371

  2. Multi-coil approach to reduce electromagnetic energy absorption for wirelessly powered implants

    PubMed Central

    Lazzi, Gianluca

    2014-01-01

    Near-field inductive coupling is a commonly used technique for wireless power transfer (WPT) in biomedical implants. Owing to the close proximity of the implant coil(s) with the tissue ( ∼1 mm) and high current ( ∼100–300 mA) in the magnetic coil(s), a significant induced electric field can be generated for the operating frequency (1–20 MHz). In this Letter, a multi-coil-based WPT technique is proposed to selectively control the currents in the external and implant coils to reduce the specific absorption rate (SAR). A three-coil WPT system, that can achieve 26% reduction in peak 1-g SAR and 15% reduction in peak 10-g SAR, as compared to a two-coil WPT system with the same dimensions, is implemented and used to demonstrate the effectiveness of the proposed approach. To achieve the seamless design for the external and implant electronics, the multi-coil system achieves the same voltage gain and bandwidth as the two-coil design with 46% improvement in the power transfer efficiency.

  3. SunShot solar power reduces costs and uncertainty in future low-carbon electricity systems.

    PubMed

    Mileva, Ana; Nelson, James H; Johnston, Josiah; Kammen, Daniel M

    2013-08-20

    The United States Department of Energy's SunShot Initiative has set cost-reduction targets of $1/watt for central-station solar technologies. We use SWITCH, a high-resolution electricity system planning model, to study the implications of achieving these targets for technology deployment and electricity costs in western North America, focusing on scenarios limiting carbon emissions to 80% below 1990 levels by 2050. We find that achieving the SunShot target for solar photovoltaics would allow this technology to provide more than a third of electric power in the region, displacing natural gas in the medium term and reducing the need for nuclear and carbon capture and sequestration (CCS) technologies, which face technological and cost uncertainties, by 2050. We demonstrate that a diverse portfolio of technological options can help integrate high levels of solar generation successfully and cost-effectively. The deployment of GW-scale storage plays a central role in facilitating solar deployment and the availability of flexible loads could increase the solar penetration level further. In the scenarios investigated, achieving the SunShot target can substantially mitigate the cost of implementing a carbon cap, decreasing power costs by up to 14% and saving up to $20 billion ($2010) annually by 2050 relative to scenarios with Reference solar costs. PMID:23865424

  4. Validity of power functionals for a homogeneous electron gas in reduced-density-matrix-functional theory

    NASA Astrophysics Data System (ADS)

    Putaja, A.; Eich, F. G.; Baldsiefen, T.; Räsänen, E.

    2016-03-01

    Physically valid and numerically efficient approximations for the exchange and correlation energy are critical for reduced-density-matrix-functional theory to become a widely used method in electronic structure calculations. Here we examine the physical limits of power functionals of the form f (n ,n') =(nn')α for the scaling function in the exchange-correlation energy. To this end we obtain numerically the minimizing momentum distributions for the three- and two-dimensional homogeneous electron gas, respectively. In particular, we examine the limiting values for the power α to yield physically sound solutions that satisfy the Lieb-Oxford lower bound for the exchange-correlation energy and exclude pinned states with the condition n (k )<1 for all wave vectors k . The results refine the constraints previously obtained from trial momentum distributions. We also compute the values for α that yield the exact correlation energy and its kinetic part for both the three- and two-dimensional electron gas. In both systems, narrow regimes of validity and accuracy are found at α ≳0.6 and at rs≳10 for the density parameter, corresponding to relatively low densities.

  5. Design and real time implementation of fuzzy switched controller for single phase active power filter.

    PubMed

    Afghoul, Hamza; Krim, Fateh; Chikouche, Djamel; Beddar, Antar

    2015-09-01

    This paper proposes a novel fuzzy switched controller (FSC) integrated in direct current control (DCC) algorithm for single phase active power filter (SPAPF). The controller under study consists of conventional PI controller, fractional order PI controller (FO-PI) and fuzzy decision maker (FDM) that switches between them using reduced fuzzy logic control. The proposed controller offers short response time with low damping and deals efficiently with the external disturbances while preserving the robustness properties. To fulfill the requirements of power quality, unity power factor and harmonics limitations in active power filtering an experimental test bench has been built using dSPACE 1104 to demonstrate the feasibility and effectiveness of the proposed controller. The obtained results present high performance in steady and transient states. PMID:26233491

  6. USE OF COAL DRYING TO REDUCE WATER CONSUMED IN PULVERIZED COAL POWER PLANTS

    SciTech Connect

    Edward Levy

    2005-10-01

    Low rank fuels such as subbituminous coals and lignites contain significant amounts of moisture compared to higher rank coals. Typically, the moisture content of subbituminous coals ranges from 15 to 30 percent, while that for lignites is between 25 and 40 percent, where both are expressed on a wet coal basis. High fuel moisture has several adverse impacts on the operation of a pulverized coal generating unit. High fuel moisture results in fuel handling problems, and it affects heat rate, mass rate (tonnage) of emissions, and the consumption of water needed for evaporative cooling. This project deals with lignite and subbituminous coal-fired pulverized coal power plants, which are cooled by evaporative cooling towers. In particular, the project involves use of power plant waste heat to partially dry the coal before it is fed to the pulverizers. Done in a proper way, coal drying will reduce cooling tower makeup water requirements and also provide heat rate and emissions benefits. The technology addressed in this project makes use of the hot circulating cooling water leaving the condenser to heat the air used for drying the coal (Figure 1). The temperature of the circulating water leaving the condenser is usually about 49 C (120 F), and this can be used to produce an air stream at approximately 43 C (110 F). Figure 2 shows a variation of this approach, in which coal drying would be accomplished by both warm air, passing through the dryer, and a flow of hot circulating cooling water, passing through a heat exchanger located in the dryer. Higher temperature drying can be accomplished if hot flue gas from the boiler or extracted steam from the turbine cycle is used to supplement the thermal energy obtained from the circulating cooling water. Various options such as these are being examined in this investigation. This is the eleventh Quarterly Report for this project. The background and technical justification for the project are described, including potential benefits

  7. Arterial chemoreceptor activation reduces the activity of parapyramidal serotonergic neurons in rats.

    PubMed

    Takakura, A C; Moreira, T S

    2013-05-01

    The parapyramidal (ppy) region targets primarily the intermediolateral cell column and is probably involved in breathing and thermoregulation. In the present study, we tested whether ppy serotonergic neurons respond to activation of central and peripheral chemoreceptors. Bulbospinal ppy neurons (n=30) were recorded extracellularly along with the phrenic nerve activity in urethane/α-chloralose-anesthetized, paralyzed, intact (n=7) or carotid body denervated (n=6) male Wistar rats. In intact animals, most of the ppy neurons were inhibited by hypoxia (n=14 of 19) (8% O2, 30s) (1.5 ± 0.03 vs. control: 2.4 ± 0.2 Hz) or hypercapnia (n=15 of 19) (10% CO2) (1.7 ± 0.1 vs. control: 2.2 ± 0.2 Hz), although some neurons were insensitive to hypoxia (n=3 of 19) or hypercapnia (n=4 of 19). Very few neurons (n=2 of 19) were activated after hypoxia, but not after hypercapnia. In carotid body denervated rats, all the 5HT-ppy neurons (n=11) were insensitive to hypercapnia (2.1 ± 0.1 vs. control: 2.3 ± 0.09 Hz). Biotinamide-labeled cells that were recovered after histochemistry were located in the ppy region. Most labeled cells (90%) showed strong tryptophan hydroxylase immunocytochemical reactivity, indicating that they were serotonergic. The present data reveal that peripheral chemoreceptors reduce the activity of the serotonergic premotor neurons located in the ppy region. It is plausible that the serotonergic neurons of the ppy region could conceivably regulate breathing automaticity and be involved in autonomic regulation. PMID:23403178

  8. Arctic Black Carbon Initiative: Reducing Emissions of Black Carbon from Power & Industry in Russia

    NASA Astrophysics Data System (ADS)

    Cresko, J.; Hodson, E. L.; Cheng, M.; Fu, J. S.; Huang, K.; Storey, J.

    2012-12-01

    Deposition of black carbon (BC) on snow and ice is widely considered to have a climate warming effect by reducing the surface albedo and promoting snowmelt. Such positive climate feedbacks in the Arctic are especially problematic because rising surface temperatures may trigger the release of large Arctic stores of terrestrial carbon, further amplifying current warming trends. Recognizing the Arctic as a vulnerable region, the U.S. government committed funds in Copenhagen in 2009 for international cooperation targeting Arctic BC emissions reductions. As a result, the U.S. Department of State has funded three research and demonstration projects with the goal to better understand and mitigate BC deposition in the Russian Arctic from a range of sources. The U.S. Department of Energy's (DOE) Arctic BC initiative presented here is focused on mitigating BC emissions resulting from heat and power generation as well as industrial applications. A detailed understanding of BC sources and its transport and fate is required to prioritize efforts to reduce BC emissions from sources that deposit in the Russian Arctic. Sources of BC include the combustion of fossil fuels (e.g. coal, fuel oil, diesel) and the combustion of biomass (e.g. wildfires, agricultural burning, residential heating and cooking). Information on fuel use and associated emissions from the industrial and heat & power sectors in Russia is scarce and difficult to obtain from the open literature. Hence, our project includes a research component designed to locate Arctic BC emissions sources in Russia and determine associated BC transport patterns. We use results from the research phase to inform a subsequent assessment/demonstration phase. We use a back-trajectory modeling method (potential source contribution function - PSCF), which combines multi-year, high-frequency measurements with knowledge about atmospheric transport patterns. The PSCF modeling allows us to map the probability (by season and year) at course

  9. New hybrid active power filter for harmonic current suppression and reactive power compensation

    NASA Astrophysics Data System (ADS)

    Biricik, Samet; Cemal Ozerdem, Ozgur; Redif, Soydan; Sezai Dincer, Mustafa

    2016-08-01

    In the case of undistorted and balanced grid voltages, low ratio shunt active power filters (APFs) can give unity power factors and achieve current harmonic cancellation. However, this is not possible when source voltages are distorted and unbalanced. In this study, the cost-effective hybrid active power filter (HAPF) topology for satisfying the requirements of harmonic current suppression and non-active power compensation for industry is presented. An effective strategy is developed to observe the effect of the placement of power capacitors and LC filters with the shunt APF. A new method for alleviating the negative effects of a nonideal grid voltage is proposed that uses a self-tuning filter algorithm with instantaneous reactive power theory. The real-time control of the studied system was achieved with a field-programmable gate array (FPGA) architecture, which was developed using the OPAL-RT system. The performance result of the proposed HAPF system is tested and presented under nonideal supply voltage conditions.

  10. Economic and environmental benefits of reducing standby power lossin DVD/VCD players and copiers in China

    SciTech Connect

    Lin, Jiang; Li, Tienan; Li, Aizhen; Zhang, Guoqing

    2004-06-01

    's certification activities. Media events organized by CECP have greatly improved the country's awareness of standby power loss. Reducing standby power loss has been formally incorporated into China's energy efficiency policy portfolio and in China's collaboration with the international community on the subject of energy efficiency (IEA, 2001). In phase II of the program, CECP's main task was to assess the market for DVD/VCD (Digital Versatile/Video Disc and Video Compact Disc) players and copiers to analyze the economic and technical benefits of energy conservation potential, and to develop technical specifications for DVD/VCD players and copiers, with technical assistance from LBNL. Having built on the success of Phase I, CECP paid great attention to the appraisal of market conditions and the economic and environmental benefits of reducing standby power loss in DVD/VCD players and copiers, and solicited inputs from stakeholders before finalizing the product certification requirements. This paper summarizes the expected energy conservation and environmental benefits due to the implementation of certification programs for DVD/VCD players and copiers in China.

  11. POTENTIAL HEALTH RISK REDUCTION ARISING FROM REDUCED MERCURY EMISSIONS FROM COAL FIRED POWER PLANTS.

    SciTech Connect

    Sullivan, T. M.; Lipfert, F. W.; Morris, S. C.; Moskowitz, P. D.

    2001-09-01

    The U.S. Environmental Protection Agency (EPA) has announced plans to regulate mercury (Hg) emissions from coal-fired power plants. EPA has not prepared a quantitative assessment of the reduction in risk that could be achieved through reduction in coal plant emissions of Hg. To address this issue, Brookhaven National Laboratory (BNL) with support from the U.S. Department of Energy Office of Fossil Energy (DOE FE) prepared a quantitative assessment of the reduction in human health risk that could be achieved through reduction in coal plant emissions of Hg. The primary pathway for Hg exposure is through consumption of fish. The most susceptible population to Hg exposure is the fetus. Therefore the risk assessment focused on consumption of fish by women of child-bearing age. Dose response factors were generated from studies on loss of cognitive abilities (language skills, motor skills, etc.) by young children whose mothers consumed large amounts of fish with high Hg levels. Population risks were estimated for the general population in three regions of the country, (the Midwest, Northeast, and Southeast) that were identified by EPA as being heavily impacted by coal emissions. Three scenarios for reducing Hg emissions from coal plants were considered: (1) A base case using current conditions; (2) A 50% reduction; and, (3) A 90% reduction. These reductions in emissions were assumed to translate linearly into a reduction in fish Hg levels of 8.6% and 15.5%, respectively. Population risk estimates were also calculated for two subsistence fisher populations. These groups of people consume substantially more fish than the general public and, depending on location, the fish may contain higher Hg levels than average. Risk estimates for these groups were calculated for the three Hg levels used for the general population analyses. Analysis shows that the general population risks for exposure of the fetus to Hg are small. Estimated risks under current conditions (i.e., no

  12. Plasma Switch for High-Power Active Pulse Compressor

    SciTech Connect

    Hirshfield, Jay L.

    2013-11-04

    Results are presented from experiments carried out at the Naval Research Laboratory X-band magnicon facility on a two-channel X-band active RF pulse compressor that employed plasma switches. Experimental evidence is shown to validate the basic goals of the project, which include: simultaneous firing of plasma switches in both channels of the RF circuit, operation of quasi-optical 3-dB hybrid directional coupler coherent superposition of RF compressed pulses from both channels, and operation of the X-band magnicon directly in the RF pulse compressor. For incident 1.2 ?s pulses in the range 0.63 ? 1.35 MW, compressed pulses of peak powers 5.7 ? 11.3 MW were obtained, corresponding to peak power gain ratios of 8.3 ? 9.3. Insufficient bakeout and conditioning of the high-power RF circuit prevented experiments from being conducted at higher RF input power levels.

  13. Phytochemical characterization, antimicrobial activity and reducing potential of seed oil, latex, machine oil and presscake of Jatropha curcas

    PubMed Central

    Sharma, Amit Kumar; Gangwar, Mayank; Kumar, Dharmendra; Nath, Gopal; Kumar Sinha, Akhoury Sudhir; Tripathi, Yamini Bhushan

    2016-01-01

    Objective: This study aims to evaluate the antimicrobial activity, phytochemical studies and thin layer chromatography analysis of machine oil, hexane extract of seed oil and methanol extract of presscake & latex of Jatropha curcas Linn (family Euphorbiaceae). Materials and Methods: J. curcas extracts were subjected to preliminary qualitative phytochemical screening to detect the major phytochemicals followed by its reducing power and content of phenol and flavonoids in different fractions. Thin layer chromatography was also performed using different solvent systems for the analysis of a number of constituents in the plant extracts. Antimicrobial activity was evaluated by the disc diffusion method, while the minimum inhibitory concentration, minimum bactericidal concentration and minimum fungicidal concentration were calculated by micro dilution method. Results: The methanolic fraction of latex and cake exhibited marked antifungal and antibacterial activities against Gram-positive and Gram-negative bacteria. Phytochemical analysis revealed the presence of alkaloids, saponins, tannins, terpenoids, steroids, glycosides, phenols and flavonoids. Reducing power showed dose dependent increase in concentration compared to standard Quercetin. Furthermore, this study recommended the isolation and separation of bioactive compounds responsible for the antibacterial activity which would be done by using different chromatographic methods such as high-performance liquid chromatography (HPLC), GC-MS etc. Conclusion: The results of the above study suggest that all parts of the plants possess potent antibacterial activity. Hence, it is important to isolate the active principles for further testing of antimicrobial and other biological efficacy. PMID:27516977

  14. Increasing the power density when using inert matrix fuels to reduce production of transuranics

    SciTech Connect

    Recktenwald, G.D.; Deinert, M.R.

    2013-07-01

    Reducing the production of transuranics is a goal of most advanced nuclear fuel cycles. One way to do this is to recycle the transuranics into the same reactors that are currently producing them using an inert matrix fuel. In previous work we have modeled such a reactor where 72%, of the core is comprised of standard enriched uranium fuel pins, with the remaining 28% fuel made from Yttria stabilized zirconium, in which transuranics are loaded. A key feature of this core is that all of the transuranics produced by the uranium fuel assemblies are later burned in inert matrix fuel assemblies. It has been shown that this system can achieve reductions in transuranic waste of more than 86%. The disadvantage of such a system is that the core power rating must be significantly lower than a standard pressurized water reactor. One reason for the lower power is that high burnup of the uranium fuel precludes a critical level of reactivity at the end of the campaign. Increasing the uranium enrichment and changing the pin pitch are two ways to increase burnup while maintaining criticality. In this paper we use MCNPX and a linear reactivity model to quantify the effect of these two parameters on the end of campaign reactivity. Importantly, we show that in the region of our proposed reactor, enrichment increases core reactivity by 0.02 per percent uranium 235 and pin pitch increases reactivity by 0.02 per mm. Reactivity is lost at a rate of 0.005 per MWd/kgIHM uranium burnup. (authors)

  15. Unified active and reactive power modulation of HVDC transmission systems

    NASA Astrophysics Data System (ADS)

    Grund, C. E.; Pohl, R. V.

    1981-11-01

    The power modulation of a high voltage direct current (HVDC) system for stabilization of an ac/dc network was investigated. It was found that simultaneous modulation of both dc current and voltage was more effective than just current modulation by itself, since the dc voltage modulation could be used to minimize the reactive power changes resulting from a change of the dc current. This helps stabilize the ac busbar voltages at the converters, which reduces undesirable load flow changes to voltage dependent ac loads, thus improving the effectiveness of the dc power modulation. This unified modulation control concept was evaluated by means of digital computer studies as well as a special purpose HVDC simulator. Several combined ac/dc power transmission systems were synthesized for testing of different modulation controller concepts. An optimum controller design incorporating a linear quadratic control algorithm with full state feedback was first studied. This provided a basis for comparison of suboptimal controller designs utilizing reduced state feedback and a Kalman filter state reconstruction technique.

  16. Denervation-Induced Activation of the Ubiquitin-Proteasome System Reduces Skeletal Muscle Quantity Not Quality.

    PubMed

    Baumann, Cory W; Liu, Haiming M; Thompson, LaDora V

    2016-01-01

    It is well known that the ubiquitin-proteasome system is activated in response to skeletal muscle wasting and functions to degrade contractile proteins. The loss of these proteins inevitably reduces skeletal muscle size (i.e., quantity). However, it is currently unknown whether activation of this pathway also affects function by impairing the muscle's intrinsic ability to produce force (i.e., quality). Therefore, the purpose of this study was twofold, (1) document how the ubiquitin-proteasome system responds to denervation and (2) identify the physiological consequences of these changes. To induce soleus muscle atrophy, C57BL6 mice underwent tibial nerve transection of the left hindlimb for 7 or 14 days (n = 6-8 per group). At these time points, content of several proteins within the ubiquitin-proteasome system were determined via Western blot, while ex vivo whole muscle contractility was specifically analyzed at day 14. Denervation temporarily increased several key proteins within the ubiquitin-proteasome system, including the E3 ligase MuRF1 and the proteasome subunits 19S, α7 and β5. These changes were accompanied by reductions in absolute peak force and power, which were offset when expressed relative to physiological cross-sectional area. Contrary to peak force, absolute and relative forces at submaximal stimulation frequencies were significantly greater following 14 days of denervation. Taken together, these data represent two keys findings. First, activation of the ubiquitin-proteasome system is associated with reductions in skeletal muscle quantity rather than quality. Second, shortly after denervation, it appears the muscle remodels to compensate for the loss of neural activity via changes in Ca2+ handling. PMID:27513942

  17. Denervation-Induced Activation of the Ubiquitin-Proteasome System Reduces Skeletal Muscle Quantity Not Quality

    PubMed Central

    Liu, Haiming M.; Thompson, LaDora V.

    2016-01-01

    It is well known that the ubiquitin-proteasome system is activated in response to skeletal muscle wasting and functions to degrade contractile proteins. The loss of these proteins inevitably reduces skeletal muscle size (i.e., quantity). However, it is currently unknown whether activation of this pathway also affects function by impairing the muscle’s intrinsic ability to produce force (i.e., quality). Therefore, the purpose of this study was twofold, (1) document how the ubiquitin-proteasome system responds to denervation and (2) identify the physiological consequences of these changes. To induce soleus muscle atrophy, C57BL6 mice underwent tibial nerve transection of the left hindlimb for 7 or 14 days (n = 6–8 per group). At these time points, content of several proteins within the ubiquitin-proteasome system were determined via Western blot, while ex vivo whole muscle contractility was specifically analyzed at day 14. Denervation temporarily increased several key proteins within the ubiquitin-proteasome system, including the E3 ligase MuRF1 and the proteasome subunits 19S, α7 and β5. These changes were accompanied by reductions in absolute peak force and power, which were offset when expressed relative to physiological cross-sectional area. Contrary to peak force, absolute and relative forces at submaximal stimulation frequencies were significantly greater following 14 days of denervation. Taken together, these data represent two keys findings. First, activation of the ubiquitin-proteasome system is associated with reductions in skeletal muscle quantity rather than quality. Second, shortly after denervation, it appears the muscle remodels to compensate for the loss of neural activity via changes in Ca2+ handling. PMID:27513942

  18. Reducing Dilution and Analysis Time in Online Comprehensive Two-Dimensional Liquid Chromatography by Active Modulation.

    PubMed

    Gargano, Andrea F G; Duffin, Mike; Navarro, Pablo; Schoenmakers, Peter J

    2016-02-01

    Online comprehensive two-dimensional liquid chromatography (LC × LC) offers ways to achieve high-performance separations in terms of peak capacity (exceeding 1000) and additional selectivity to realize applications that cannot be addressed with one-dimensional chromatography (1D-LC). However, the greater resolving power of LC × LC comes at the price of higher dilutions (thus, reduced sensitivity) and, often, long analysis times (>100 min). The need to preserve the separation attained in the first dimension ((1)D) causes greater dilution for LC × LC, in comparison with 1D-LC, and long analysis times to sample the (1)D with an adequate number of second dimension separations. A way to significantly reduce these downsides is to introduce a concentration step between the two chromatographic dimensions. In this work we present a possible active-modulation approach to concentrate the fractions of (1)D effluent. A typical LC × LC system is used with the addition of a dilution flow to decrease the strength of the (1)D effluent and a modulation unit that uses trap columns. The potential of this approach is demonstrated for the separation of tristyrylphenol ethoxylate phosphate surfactants, using a combination of hydrophilic interaction and reversed-phase liquid chromatography. The modified LC × LC system enabled us to halve the analysis time necessary to obtain a similar degree of separation efficiency with respect to UHPLC based LC × LC and of 5 times with respect to HPLC instrumentation (40 compared with 80 and 200 min, respectively), while at the same time reducing dilution (DF of 142, 299, and 1529, respectively) and solvent consumption per analysis (78, 120, and 800 mL, respectively). PMID:26709410

  19. Shade trees reduce building energy use and CO2 emissions from power plants

    SciTech Connect

    Akbari, H.

    2001-11-01

    Urban shade trees offer significant benefits in reducing building air-conditioning demand and improving urban air quality by reducing smog. The savings associated with these benefits vary by climate region and can be up to $200 per tree. The cost of planting trees and maintaining them can vary from $10 to $500 per tree. Tree-planting programs can be designed to have lower costs so that they offer potential savings to communities that plant trees. Our calculations suggest that urban trees play a major role in sequestering C02 and thereby delay global warming. We estimate that a tree planted in Los Angeles avoids the combustion of 18 kg of carbon annually, even though it sequesters only 4.5-11 kg (as it would if growing in a forest). In this sense, one shade tree in Los Angeles is equivalent to three to five forest trees. In a recent analysis for Baton Rouge, Sacramento, and Salt Lake City, we estimated that planting an average of four shade trees per house (each with a top view cross section of 50 m2) would lead to an annual reduction in carbon emissions from power plants of 16,000, 41,000, and 9000 t, respectively (the per-tree reduction in carbon emissions is about 10-11 kg per year). These reductions only account for the direct reduction in the net cooling- and heating-energy use of buildings. Once the impact of the community cooling is included, these savings are increased by at least 25 percent.

  20. Reduced-Order Models for Load Management in the Power Grid

    NASA Astrophysics Data System (ADS)

    Alizadeh, Mahnoosh

    In recent years, considerable research efforts have been directed towards designing control schemes that can leverage the inherent flexibility of electricity demand that is not tapped into in today's electricity markets. It is expected that these control schemes will be carried out by for-profit entities referred to as aggregators that operate at the edge of the power grid network. While the aggregator control problem is receiving much attention, more high-level questions of how these aggregators should plan their market participation, interact with the main grid and with each other, remain rather understudied. Answering these questions requires a large-scale model for the aggregate flexibility that can be harnessed from the a population of customers, particularly for residences and small businesses. The contribution of this thesis towards this goal is divided into three parts: In Chapter 3, a reduced-order model for a large population of heterogeneous appliances is provided by clustering load profiles that share similar degrees of freedom together. The use of such reduced-order model for system planning and optimal market decision making requires a foresighted approximation of the number of appliances that will join each cluster. Thus, Chapter 4 provides a systematic framework to generate such forecasts for the case of Electric Vehicles, based on real-world battery charging data. While these two chapters set aside the economic side that is naturally involved with participation in demand response programs and mainly focus on the control problem, Chapter 5 is dedicated to the study of optimal pricing mechanisms in order to recruit heterogeneous customers in a demand response program in which an aggregator can directly manage their appliances' load under their specified preferences. Prices are proportional to the wholesale market savings that can result from each recruitment event.

  1. Shade trees reduce building energy use and CO2 emissions from power plants.

    PubMed

    Akbari, H

    2002-01-01

    Urban shade trees offer significant benefits in reducing building air-conditioning demand and improving urban air quality by reducing smog. The savings associated with these benefits vary by climate region and can be up to $200 per tree. The cost of planting trees and maintaining them can vary from $10 to $500 per tree. Tree-planting programs can be designed to have lower costs so that they offer potential savings to communities that plant trees. Our calculations suggest that urban trees play a major role in sequestering CO2 and thereby delay global warming. We estimate that a tree planted in Los Angeles avoids the combustion of 18 kg of carbon annually, even though it sequesters only 4.5-11 kg (as it would if growing in a forest). In this sense, one shade tree in Los Angeles is equivalent to three to five forest trees. In a recent analysis for Baton Rouge, Sacramento, and Salt Lake City, we estimated that planting an average of four shade trees per house (each with a top view cross section of 50 m2) would lead to an annual reduction in carbon emissions from power plants of 16,000, 41,000, and 9000 t, respectively (the per-tree reduction in carbon emissions is about 10-11 kg per year). These reductions only account for the direct reduction in the net cooling- and heating-energy use of buildings. Once the impact of the community cooling is included, these savings are increased by at least 25%. PMID:11833899

  2. Qualification of active mechanical components for nuclear power plants

    SciTech Connect

    Allen, R.D.; Mollerus, F.J.

    1983-11-01

    The Electric Power Research Institute has undertaken a study of active safety related mechanical components in domestic nuclear plants to determine what qualification information exists and to establish a plan for qualification of those components. Active safety related mechanical components are those which undergo mechanical motion to perform a safety function. The overall objective of the study is to recommend appropriate methods and realistic criteria for the environmental, seismic and dynamic qualification of active mechanical components. This paper presents the results of progress in this project through May 1983.

  3. Nitrate removal performance of Diaphorobacter nitroreducens using biodegradable plastics as the source of reducing power

    NASA Astrophysics Data System (ADS)

    Khan, S. T.; Nagao, Y.; Hiraishi, A.

    2015-02-01

    Strain NA10BT and other two strains of the denitrifying betaproteobacterium Diaphorobacter nitroreducens were studied for the performance of solid-phase denitrification (SPD) using poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) and some other biodegradable plastics as the source of reducing power in wastewater treatment. Sequencing-batch SPD reactors with these organisms and PHBV granules or flakes as the substrate exhibited good nitrate removal performance. Vial tests using cultures from these parent reactors showed higher nitrate removal rates with PHBV granules (ca. 20 mg-NO3-- N g-1 [dry wt cells] h-1) than with PHBV pellets and flakes. In continuous-flow SPD reactors using strain NA10BT and PHBV flakes, nitrate was not detected even at a loading rate of 21 mg-NO3-- N L-1 h-1. This corresponded to a nitrate removal rate of 47 mg-NO3-- N g-1 (dry wt cells) h-1. In the continuous-flow reactor, the transcription level of the phaZ gene, coding for PHB depolymerase, decreased with time, while that of the nosZ gene, involved in denitrificaiton, was relatively constant. These results suggest that the bioavailability of soluble metabolites as electron donor and carbon sources increases with time in the continuous-flow SPD process, thereby having much higher nitrate removal rates than the process with fresh PHBV as the substrate.

  4. A model of plant isoprene emission based on available reducing power captures responses to atmospheric CO₂.

    PubMed

    Morfopoulos, Catherine; Sperlich, Dominik; Peñuelas, Josep; Filella, Iolanda; Llusià, Joan; Medlyn, Belinda E; Niinemets, Ülo; Possell, Malcolm; Sun, Zhihong; Prentice, Iain Colin

    2014-07-01

    We present a unifying model for isoprene emission by photosynthesizing leaves based on the hypothesis that isoprene biosynthesis depends on a balance between the supply of photosynthetic reducing power and the demands of carbon fixation. We compared the predictions from our model, as well as from two other widely used models, with measurements of isoprene emission from leaves of Populus nigra and hybrid aspen (Populus tremula × P. tremuloides) in response to changes in leaf internal CO2 concentration (C(i)) and photosynthetic photon flux density (PPFD) under diverse ambient CO2 concentrations (C(a)). Our model reproduces the observed changes in isoprene emissions with C(i) and PPFD, and also reproduces the tendency for the fraction of fixed carbon allocated to isoprene to increase with increasing PPFD. It also provides a simple mechanism for the previously unexplained decrease in the quantum efficiency of isoprene emission with increasing C(a). Experimental and modelled results support our hypothesis. Our model can reproduce the key features of the observations and has the potential to improve process-based modelling of isoprene emissions by land vegetation at the ecosystem and global scales. PMID:24661143

  5. The production of activated carbon using the equipment of thermal power plants and heating plants

    NASA Astrophysics Data System (ADS)

    Osintsev, K. V.; Osintsev, V. V.; Dzhundubaev, A. K.; Kim, S. P.; Al'musin, G. T.; Akbaev, T. A.; Bogatkin, V. I.

    2013-08-01

    The production technology of activated carbon using the conventional equipment of the thermal power stations and boiler houses is proposed. The obtained product is directed into the systems of chemical water preparation and water drain of enterprises. The production cycle is invariable when producing the activated carbon by the proposed technology. The fuel consumption and heat losses are considerably reduced when implementing this technology compared with the known analogs of the carbon sorbent. The production efficiency increases if small dust particles are preliminary separated and coal is activated in narrow ranges of fraction sizes.

  6. Large active retrodirective arrays for solar power satellites

    NASA Technical Reports Server (NTRS)

    Chernoff, R.

    1978-01-01

    An active retrodirective array (ARA) transmits a beam toward the apparent source of an illuminating signal called the pilot. The array produces the RF power. Retrodirectivity is achieved by retransmitting from each element of the array a signal whose phase is the 'conjugate' of that received by the element. Application of the ARA to the solar power satellite concept has been proposed. A method of providing a reference phase is described, called 'central phasing', which eliminates the need for a rigid structure ordinarily needed in order to realize accurate retrodirectivity.

  7. Experimental evaluation of a self-powered smart damping system in reducing vibrations of a full-scale stay cable

    NASA Astrophysics Data System (ADS)

    Kim, In-Ho; Jung, Hyung-Jo; Koo, Jeong-Hoi

    2010-11-01

    This paper investigates the effectiveness of a self-powered smart damping system consisting of a magnetorheological (MR) damper and an electromagnetic induction (EMI) device in reducing cable vibrations. The proposed smart damping system incorporates an EMI device, which is capable of converting vibration energy into useful electrical energy. Thus, the incorporated EMI device can be used as an alternative power source for the MR damper, making it a self-powering system. The primary goal of this experimental study is to evaluate the performance of the proposed smart damping system using a full-scale, 44.7 m long, high-tension cable. To this end, an EMI part and an MR damper were designed and manufactured. Using a cable test setup in a laboratory setting, a series of tests were performed to evaluate the effectiveness of the self-powered smart damping system in reducing free vibration responses of the cable. The performances of the proposed smart damping system are compared with those of an equivalent passive system. Moreover, the damping characteristics of the smart damping system and the passive system are compared. The experimental results show that the self-powered smart damping system outperforms the passive control cases in reducing the vibrations of the cable. The results also show that the EMI can operate the smart damping system as a sole power source, demonstrating the feasibility of the self-powering capability of the system.

  8. Improved antitumor activity and reduced myocardial toxicity of doxorubicin encapsulated in MPEG-PCL nanoparticles.

    PubMed

    Sun, Chuntang; Zhou, Le; Gou, Maling; Shi, Shuai; Li, Tao; Lang, Jinyi

    2016-06-01

    Doxorubicin (Dox) is a broad-spectrum antitumor drug used for the treatment of many types of malignant tumors. Although it possesses powerful antitumor activity, its clinical application is seriously encumbered by its unselective distribution and systemic toxicities, particularly myocardial toxicity. Thus, it is imperative to modify Dox to decrease its systemic toxicities and improve its therapeutic index. In the present study, we adopted a novel type of monomethoxy poly(ethylene glycol)-poly(ε-caprolactone) (MPEG-PCL) micelles to encapsulate Dox to prepare Dox-loaded MPEG-PCL (Dox/MPEG-PCL) nanoparticles by a controllable self-assembly process. The cellular uptake efficiency and cell proliferation inhibition of the Dox/MPEG-PCL nanoparticles were examined. The antitumor activity of the Dox/MPEG-PCL nanoparticles was tested on a multiple pulmonary metastasis model of melanoma on C57BL/6 mice. Systemic toxicities and survival time were compared between the mice treated with the Dox/MPEG-PCL nanoparticles and free Dox. The potential myocardial toxicity of the Dox/MPEG-PCL nanoparticles was investigated using a prolonged observation period. Encapsulation of Dox in MPEG-PCL nanoparticles significantly improved the cellular uptake and cell proliferation inhibition of Dox in vivo. Intravenous injection of Dox/MPEG-PCL nanoparticles obtained significant inhibition of the growth and metastasis of melanoma in the lung and prolonged survival time compared with free Dox (P<0.05). The Dox/MPEG-PCL nanoparticles did not show obvious additional systemic toxicities compared with free Dox during the treatment time. During the prolonged observation period, obvious decreased cardiac toxicity was observed in the Dox/MPEG-PCL nanoparticle-treated mice compared with that observed in the free Dox-treated mice. These results indicated that encapsulating Dox with MPEG-PCL micelles could significantly promote its antitumor activity and reduce its toxicity to the myocardium. PMID

  9. Regular physical activity has differential association with reduced obesity among diverse youth in the United States.

    PubMed

    Fradkin, Chris; Wallander, Jan L; Elliott, Marc N; Cuccaro, Paula; Schuster, Mark A

    2016-08-01

    This study examined whether daily or almost daily lower-intensity physical activity was associated with reduced obesity, among 4824 African American, Hispanic, and White youth assessed in fifth and seventh grades. Regular lower-intensity physical activity was associated with reduced obesity only among Hispanic and White males and only in seventh grade, and not among youth in fifth grade, females, or African American males or females. Findings from this study suggest that the reduced obesity risk generally attributed to physical activity may not be consistent across racial/ethnic and gender groups of early adolescents. PMID:25476573

  10. Nitrate removal performance of Diaphorobacter nitroreducens using biodegradable plastics as the source of reducing power

    SciTech Connect

    Khan, S. T.; Nagao, Y.; Hiraishi, A.

    2015-02-27

    Strain NA10B{sup T} and other two strains of the denitrifying betaproteobacterium Diaphorobacter nitroreducens were studied for the performance of solid-phase denitrification (SPD) using poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) and some other biodegradable plastics as the source of reducing power in wastewater treatment. Sequencing-batch SPD reactors with these organisms and PHBV granules or flakes as the substrate exhibited good nitrate removal performance. Vial tests using cultures from these parent reactors showed higher nitrate removal rates with PHBV granules (ca. 20 mg-NO{sub 3}{sup −}‐N g{sup −1} [dry wt cells] h{sup −1}) than with PHBV pellets and flakes. In continuous-flow SPD reactors using strain NA10B{sup T} and PHBV flakes, nitrate was not detected even at a loading rate of 21 mg-NO{sub 3}{sup −}‐N L{sup −1} h{sup −1}. This corresponded to a nitrate removal rate of 47 mg-NO{sub 3}{sup −}‐N g{sup −1} (dry wt cells) h{sup −1}. In the continuous-flow reactor, the transcription level of the phaZ gene, coding for PHB depolymerase, decreased with time, while that of the nosZ gene, involved in denitrificaiton, was relatively constant. These results suggest that the bioavailability of soluble metabolites as electron donor and carbon sources increases with time in the continuous-flow SPD process, thereby having much higher nitrate removal rates than the process with fresh PHBV as the substrate.

  11. USE OF COAL DRYING TO REDUCE WATER CONSUMED IN PULVERIZED COAL POWER PLANTS

    SciTech Connect

    Edward K. Levy; Nenad Sarunac; Wei Zhang

    2004-07-01

    This is the sixth Quarterly Report for this project. The background and technical justification for the project are described, including potential benefits of reducing fuel moisture, prior to firing in a pulverized coal boiler. Coal drying experiments were performed with a Powder River Basin coal to measure the effects of fluidization velocity and drying temperature on rate of drying in a batch drying process. Comparisons to computational results using the batch bed drying model show good agreement. Comparisons to drying results with North Dakota lignite at the same process conditions confirm the lignite dries slightly more rapidly than the PRB. Experiments were also carried out to determine the effects of inlet air humidity on drying rate. The specific humidity ranged from a value typical for air at temperatures near freezing to a value for 30 C air at 90 percent relative humidity. The experimental results show drying rate is strongly affected by inlet air humidity, with the rate decreasing with more humid inlet air. The temperature of the drying process also plays a strong role, with the negative impacts of high inlet moisture being less of a factor in a higher temperature drying process. Concepts for coal drying systems integrated into a power plant were developed. These make use of hot circulating cooling water from the condenser, steam extraction from the turbine cycle and thermal energy extracted from hot flue gas, in various combinations. Analyses are under way to calculate the effects of drying system design and process conditions on unit performance, emissions, and cooling tower makeup water.

  12. Impurity content of reduced-activation ferritic steels and a vanadium alloy

    SciTech Connect

    Klueh, R.L.; Grossbeck, M.L.; Bloom, E.E.

    1997-04-01

    Inductively coupled plasma mass spectrometry was used to analyze a reduced-activation ferritic/martensitic steel and a vanadium alloy for low-level impurities that would compromise the reduced-activation characteristics of these materials. The ferritic steel was from the 5-ton IEA heat of modified F82H, and the vanadium alloy was from a 500-kg heat of V-4Cr-4Ti. To compare techniques for analysis of low concentrations of impurities, the vanadium alloy was also examined by glow discharge mass spectrometry. Two other reduced-activation steels and two commercial ferritic steels were also analyzed to determine the difference in the level of the detrimental impurities in the IEA heat and steels for which no extra effort was made to restrict some of the tramp impurities. Silver, cobalt, molybdenum, and niobium proved to be the tramp impurities of most importance. The levels observed in these two materials produced with present technology exceeded the limits for low activation for either shallow land burial or recycling. The chemical analyses provide a benchmark for the improvement in production technology required to achieve reduced activation; they also provide a set of concentrations for calculating decay characteristics for reduced-activation materials. The results indicate the progress that has been made and give an indication of what must still be done before the reduced-activation criteria can be achieved.

  13. Effects of submaximal activation on the determinants of power of chemically skinned rat soleus fibres.

    PubMed

    Gilliver, S F; Degens, H; Rittweger, J; Jones, D A

    2011-02-01

    Reducing the activating calcium concentration with skinned fibres is known to decrease isometric force and maximal shortening velocity, both of which will reduce the peak power. However, power is also a function of the curvature of the force-velocity relationship, and there is limited information on how changes in activating calcium affect this important property of muscle fibres. Force-velocity relationships of permeabilized single type I fibres from rat soleus muscle were determined using isotonic contractions at 15°C with both maximal (pCa 4.5) and submaximal activation (pCa 5.6). The rate of tension redevelopment (k(tr)), which provides a measure of sum of the apparent rate constants for cross-bridge attachment and detachment (f(app) + g(app)) following a rapid release and restretch, was also measured. Compared with pCa 4.5, specific tension (P(o)) at pCa 5.6 declined by 22 ± 8% (mean ± s.d.) and the maximal velocity of shortening (V(max)) fell by 44 ± 7%, but curvature of the force-velocity relationship (a/P(o)) rose by 47 ± 31%, indicating a less concave relationship. The value of k(tr) declined by 23 ± 7%. The change in a/P(o) reduced the impact of changes in P(o) and V(max) on peak power by approximately 25%. Fitting the data to Huxley's model of cross-bridge action suggests that lower activating calcium decreased both the rate constant for cross-bridge attachment (f) and that for detachment of negatively strained cross-bridges (g(2)). The fact that V(max) (and thus g(2)) changed to a greater extent than k(tr) (f(app) + g(app)) is the reason that reduced activation results in a reduction in curvature of the force-velocity relationship. PMID:20889604

  14. Damping Control of Liquid Container by Swing-type Active Vibration Reducer on Mobile Robot

    NASA Astrophysics Data System (ADS)

    Hamaguchi, Masafumi; Taniguchi, Takao

    This paper proposes a damping control of sloshing in a cylindrical container with a swing-type active vibration reducer on a wheeled mobile robot (WMR). The WMR runs along a straight path on a horizontal plane. The container is mounted on the active vibration reducer. A laser displacement sensor is used to observe the liquid level in the container. The container can be tilted in the running direction by the active vibration reducer. A sloshing model is obtained from a spherical pendulum-type sloshing model, which approximately expresses (1, 1)-mode sloshing. The sloshing model is used to design a damping control system. The control system of the active vibration reducer is designed with an inverse model of sloshing and an optimal regulator with a Kalman filter. The WMR is driven by an acceleration pattern designed with an input shaping method. The usefulness of the proposed method is demonstrated through simulation and experimental results.

  15. Incresing antioxidant activity and reducing decay of blueberries by essential oils

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Several naturally occurring essential oils including carvacrol, anethole, cinnamaldehyde, cinnamic acid, perillaldehyde, linalool, and p-cymene were evaluated for their effectiveness in reducing decay and increasing antioxidant levels and activities in ‘Duke’ blueberries (Vaccinium corymbosum). Carv...

  16. A Single-Phase Current Source Solar Inverter with Constant Instantaneous Power, Improved Reliability, and Reduced-Size DC-Link Filter

    NASA Astrophysics Data System (ADS)

    Bush, Craig R.

    This dissertation presents a novel current source converter topology that is primarily intended for single-phase photovoltaic (PV) applications. In comparison with the existing PV inverter technology, the salient features of the proposed topology are: a) the low frequency (double of line frequency) ripple that is common to single-phase inverters is greatly reduced; b) the absence of low frequency ripple enables significantly reduced size pass components to achieve necessary DC-link stiffness and c) improved maximum power point tracking (MPPT) performance is readily achieved due to the tightened current ripple even with reduced-size passive components. The proposed topology does not utilize any electrolytic capacitors. Instead an inductor is used as the DC-link filter and reliable AC film capacitors are utilized for the filter and auxiliary capacitor. The proposed topology has a life expectancy on par with PV panels. The proposed modulation technique can be used for any current source inverter where an unbalanced three-phase operation is desires such as active filters and power controllers. The proposed topology is ready for the next phase of microgrid and power system controllers in that it accepts reactive power commands. This work presents the proposed topology and its working principle supported by with numerical verifications and hardware results. Conclusions and future work are also presented.

  17. Reduced Maximal Force during Acute Anterior Knee Pain Is Associated with Deficits in Voluntary Muscle Activation

    PubMed Central

    Salomoni, Sauro; Tucker, Kylie; Hug, François; McPhee, Megan; Hodges, Paul

    2016-01-01

    Although maximal voluntary contraction (MVC) force is reduced during pain, studies using interpolated twitch show no consistent reduction of voluntary muscle drive. The present study aimed to test if the reduction in MVC force during acute experimental pain could be explained by increased activation of antagonist muscles, weak voluntary activation at baseline, or changes in force direction. Twenty-two healthy volunteers performed maximal voluntary isometric knee extensions before, during, and after the effects of hypertonic (pain) and isotonic (control) saline injections into the infrapatellar fat pad. The MVC force, voluntary activation, electromyographic (EMG) activity of agonist, antagonist, and auxiliary (hip) muscles, and pain cognition and anxiety scores were recorded. MVC force was 9.3% lower during pain than baseline (p < 0.001), but there was no systematic change in voluntary activation. Reduced MVC force during pain was variable between participants (SD: 14%), and was correlated with reduced voluntary activation (r = 0.90), baseline voluntary activation (r = − 0.62), and reduced EMG amplitude of agonist and antagonist muscles (all r > 0.52), but not with changes in force direction, pain or anxiety scores. Hence, reduced MVC force during acute pain was mainly explained by deficits in maximal voluntary drive. PMID:27559737

  18. Design of an input filter for power factor correction (PFC) AC to DC converters employing an active ripple cancellation

    SciTech Connect

    Lee, D.Y.; Cho, B.H.

    1996-12-31

    An active input filter for power factor correction (PFC) circuit employing ripple current cancellation is proposed to reduce the filter`s size and cost.Switching ripple current can be filtered by an active circuit from the line current. A single stage passive filter with the active filter compensation circuit, a high filter can be synthesized to meet the electromagnetic interference (EMI) and power factor requirements. Analysis of the active filter and design procedure are detailed. Simulation result is presented to verify the high order filter characteristics of proposed scheme.

  19. OPTIMIZING TECHNOLOGY TO REDUCE MERCURY AND ACID GAS EMISSIONS FROM ELECTRIC POWER PLANTS

    SciTech Connect

    Jeffrey C. Quick; David E. Tabet; Sharon Wakefield; Roger L. Bon

    2005-10-01

    Maps showing potential mercury, sulfur, chlorine, and moisture emissions for U.S. coal by county of origin were made from publicly available data (plates 1, 2, 3, and 4). Published equations that predict mercury capture by emission control technologies used at U.S. coal-fired utilities were applied to average coal quality values for 169 U.S. counties. The results were used to create five maps that show the influence of coal origin on mercury emissions from utility units with: (1) hot-side electrostatic precipitator (hESP), (2) cold-side electrostatic precipitator (cESP), (3) hot-side electrostatic precipitator with wet flue gas desulfurization (hESP/FGD), (4) cold-side electrostatic precipitator with wet flue gas desulfurization (cESP/FGD), and (5) spray-dry adsorption with fabric filter (SDA/FF) emission controls (plates 5, 6, 7, 8, and 9). Net (lower) coal heating values were calculated from measured coal Btu values, and estimated coal moisture and hydrogen values; the net heating values were used to derive mercury emission rates on an electric output basis (plate 10). Results indicate that selection of low-mercury coal is a good mercury control option for plants having hESP, cESP, or hESP/FGD emission controls. Chlorine content is more important for plants having cESP/FGD or SDA/FF controls; optimum mercury capture is indicated where chlorine is between 500 and 1000 ppm. Selection of low-sulfur coal should improve mercury capture where carbon in fly ash is used to reduce mercury emissions. Comparison of in-ground coal quality with the quality of commercially mined coal indicates that existing coal mining and coal washing practice results in a 25% reduction of mercury in U.S. coal before it is delivered to the power plant. Further pre-combustion mercury reductions may be possible, especially for coal from Texas, Ohio, parts of Pennsylvania and much of the western U.S.

  20. High power VCSEL device with periodic gain active region

    NASA Astrophysics Data System (ADS)

    Ning, Y. Q., II; Qin, L.; Sun, Y. F.; Li, T.; Cui, J. J.; Peng, B.; Liu, G. Y.; Zhang, Y.; Liu, Y.; Wang, L. J.; Cui, D. F.; Xu, Z. Y.

    2007-11-01

    High power vertical cavity surface emitting lasers with large aperture have been fabricated through improving passivation, lateral oxidation and heat dissipation techniques. Different from conventional three quantum well structure, a periodic gain active region with nine quantum wells was incorporated into the VCSEL structure, with which high efficiency and high power operation were expected. The nine quantum wells were divided into three groups with each of them located at the antinodes of the cavity to enhance the coupling between the optical field and the gain region. Large aperture and bottom-emitting configuration was used to improve the beam quality and the heat dissipation. A maximum output power of 1.4W was demonstrated at CW operation for a 400μm-diameter device. The lasing wavelength shifted to 995.5nm with a FWHM of 2nm at a current of 4.8A due to the internal heating and the absence of active water cooling. A ring-shape farfield pattern was induced by the non-homogeneous lateral current distribution in large diameter device. The light intensity at the center of the ring increased with increasing current. A symmetric round light spot at the center and single transverse mode operation with a divergence angle of 16° were observed with current beyond 4.8A.

  1. Effect of viscous macromolecules on peritoneal plasminogen activator activity: a potential mechanism for their ability to reduce postoperative adhesion formation.

    PubMed

    Mayer, M; Yedgar, S; Hurwitz, A; Palti, Z; Finzi, Z; Milwidsky, A

    1988-10-01

    Activity of peritoneal plasminogen activator and its regulation by dextran and other macromolecules that clinically suppress postoperative adhesions was studied. Plasminogen activator activity was assayed by a two-stage globinolytic assay that monitors formation of plasmin, as well as by cleavage of a chromogenic peptide substrate (S-2444) in the presence of aprotinin (Trasylol). Plasminogen activator activity was located on the outer surface of human peritoneum. Incubation of peritoneal tissue with buffer in vitro (conditioning) prompted release of plasminogen activator into the conditioning medium. The released plasminogen activator formed a single band on sodium dodecyl sulfate-gel electrophoresis at an apparent molecular weight of 174,000 and was markedly suppressed by antiserum raised against human melanoma tissue-type plasminogen activator. Nonspecific proteolytic activity did not accumulate in the medium during conditioning. The presence of dextran 80 during conditioning of peritoneum reversibly suppressed tissue-bound plasminogen activator activity and reduced plasminogen activator activity in the spent medium. A similar inhibition of peritoneal plasminogen activator was induced by dextran 500, methyl cellulose, and polyvinylpyrrolidone. Dextran, when added to the medium after conditioning, had no direct inhibitory effect on plasminogen activator activity. Dextran did not induce peritoneal production of inhibitor(s) of trypsin, chymotrypsin, or urokinase. On the basis of these findings, two possible mechanisms for the effect of viscous polymers in the reduction of adhesion formation are proposed. These mechanisms consider the importance of peritoneal tissue-type plasminogen activator for removal of fibrin clots and suggest that polymer coating either prevents the shedding of plasminogen activator into the abdominal cavity or reduces the access of fibrin clots to the serosal surfaces. PMID:2459968

  2. "While you still think, I already type": experienced social power reduces deliberation during e-mail communication.

    PubMed

    Scholl, Annika; Sassenberg, Kai

    2014-11-01

    E-mail allows individuals to deliberate on their communication before sending it off. For instance, communication partners can easily take their time to ponder how best to frame a request before they actually send a message. Individuals at times strategically exploit this opportunity to deliberate in order to tailor messages to their communication partner, such as when communicating with a relatively more powerful person. As social power reduces concerns about impression management, we predicted that individuals deliberate more while composing e-mail messages under low (vs. high) power. This assumption was tested with well-established power priming. As such, we expected that experienced power in one context would diminish deliberation times during a subsequent e-mail communication. An experiment manipulating the experience of (low vs. high) power and measuring deliberation times during e-mail composition supported this hypothesis. The findings thus indicate how social power alters deliberation times. More importantly, the results show that individuals not only strategically deliberate during e-mail communication in line with their current situation, but also in line with their social standing in a previous situation (here, their experience of power). PMID:25286277

  3. Pleomorphism and acetylene-reducing activity of free-living rhizobia.

    PubMed Central

    Kaneshiro, T; Baker, F L; Johnson, D E

    1983-01-01

    Cowpea-type Rhizobium sp. strain 32H1 and Rhizobium japonicum USDA 26 and 110 grown on a glutamate-mannitol-gluconate agar medium showed increases in the number of pleomorphic cells coincident with their acetylene-reducing activity. Pleomorphs appeared to be inhibited in growth nonuniformly, because acetylene-reducing cultures were mixtures of rod, branched (V, Y, and T), and other irregularly shaped cells. In contrast, strain USDA 10 consistently failed to reduce acetylene, even though it also could grow and yield pleomorphic cells under various conditions. With minimal inhibitory supplements (5 micrograms per ml of medium) of nalidixic acid and novobiocin as cell division inhibitors, an increase in pleomorphic cells was observed, but the inhibited cultures displayed lower acetylene-reducing activity. A study of pleomorphic cells derived in different ways indicated that not all pleomorphs reduce acetylene. Images PMID:6822472

  4. Using Stable Isotopes to Assess Reduced Physical Activity of Individuals with Prader-Willi Syndrome.

    ERIC Educational Resources Information Center

    Davies, Peter S. W.; Joughlin, C.

    1993-01-01

    This study found that the physical activity levels of 10 children with Prader-Willi syndrome were significantly reduced in comparison to children without the syndrome. Increasing activity levels in children with Prader-Willi syndrome is suggested as a way to raise total energy expenditure and control weight gain. (Author/JDD)

  5. Solid Waste Educational Resources and Activities: Let's Reduce, Reuse, and Recycle. [CD-ROM].

    ERIC Educational Resources Information Center

    Environmental Protection Agency, Washington, DC. Solid Waste and Emergency Response.

    This contains games, activities, publications, and resources for students and teachers on how to reduce, reuse, recycle, and properly manage waste. It also contains a screen saver featuring runners-up from the Earth Day 2000 art contest. Activities and games include titles such as "Planet Protectors,""Recycle City,""Trash and Climate Change," and…

  6. Recycle Alaska: Reduce, Reuse, Recycle. Activities Handbook, Teacher's Guide, and Student Worksheets.

    ERIC Educational Resources Information Center

    Alaska State Dept. of Education, Juneau.

    Recycling is a very important aspect of conserving the environment for future generations. This guide addresses the topic of litter prevention for the Alaskan environment and contains 42 activities. Activity topics covered include Natural Cycles, Human Interruption of Natural Cycles, Reduce, Reuse, Recycle and Recycled Classroom. Grade level,…

  7. A novel technology to increase antioxidant activity of an antioxidant by reducing volatility

    Technology Transfer Automated Retrieval System (TEKTRAN)

    During frying, an antioxidant is lost by reaction with radicals for its antioxidant activity, but it is also lost by decomposition and evaporation before it is able to exert antioxidant activity. Some low molecular weight antioxidants are often so volatile that they show much reduced antioxidant act...

  8. Using MapReduce to Improve the Power Generation of the International Space Station

    NASA Astrophysics Data System (ADS)

    Marchetto, William R., II

    The International Space Station (ISS) spends approximately 98% of its time in orbits that experience Earth eclipse. Since the station's solar arrays produce no power when in Earth's shadow, the total power generated decreases substantially, lowering the power budget available to experimental payloads. Therefore, increasing the power output during these eclipsed orbits would be of great benefit to the space station's scientific endeavors. The ISS's current solar array configuration tracks the Sun throughout each orbit, keeping each of its 16 solar panels perpendicular to the Sun at all times. While this is the optimal orientation for solar panels with unobstructed views of the Sun, the space station's solar arrays experience shadowing from the spacecraft's structure as well as from the other solar panels. Deviating from the Sun-tracking scheme at strategic points in certain orbits can provide an increase in power output. The goal of this research was to provide a programmatic solution that increases the power generation capabilities of the ISS in orbits experiencing Earth-eclipse without requiring any physical modifications to the space station's structure. To achieve this goal, a simulator was developed to model the ISS-Earth-Sun environment and calculate the power output of the station's solar arrays based on each panel's orientation and shadowing. Many combinations of array configurations were analyzed, taking into account the physical constraints of the gimbals responsible for rotating the solar panels. The power output of the ISS was improved for the subset of Earth-eclipsed orbits that experience a high degree of shadowing from the station's structure, resulting in an average energy increase of 1.08 kWh per orbit. The power gains were achieved by quickly rotating the solar arrays through the points in each orbit that experienced the highest degree of shadowing.

  9. A High Power Density Single-Phase PWM Rectifier With Active Ripple Energy Storage

    SciTech Connect

    Wang, Ruxi; Wang, Fei; Boroyevich, Dushan; Burgos, Rolando; Lai, Rixin; Ning, Puqi; Rajashekara, Kaushik

    2011-01-01

    It is well known that single-phase pulse width modulation rectifiers have second-order harmonic currents and corresponding ripple voltages on the dc bus. The low-frequency harmonic current is normally filtered using a bulk capacitor in the bus, which results in low power density. However, pursuing high power density in converter design is a very important goal in the aerospace applications. This paper studies methods for reducing the energy storage capacitor for single-phase rectifiers. The minimum ripple energy storage requirement is derived independently of a specific topology. Based on theminimum ripple energy requirement, the feasibility of the active capacitor s reduction schemes is verified. Then, we propose a bidirectional buck boost converter as the ripple energy storage circuit, which can effectively reduce the energy storage capacitance. The analysis and design are validated by simulation and experimental results.

  10. Study of regeneration system of 300 MW power unit based on nondeaerating heat balance diagram at reduced load

    NASA Astrophysics Data System (ADS)

    Esin, S. B.; Trifonov, N. N.; Sukhorukov, Yu. G.; Yurchenko, A. Yu.; Grigor'eva, E. B.; Snegin, I. P.; Zhivykh, D. A.; Medvedkin, A. V.; Ryabich, V. A.

    2015-09-01

    More than 30 power units of thermal power stations, based on the nondeaerating heat balance diagram, successfully operate in the former Soviet Union. Most of them are power units with a power of 300 MW, equipped with HTGZ and LMZ turbines. They operate according to a variable electric load curve characterized by deep reductions when undergoing night minimums. Additional extension of the range of power unit adjustment makes it possible to maintain the dispatch load curve and obtain profit for the electric power plant. The objective of this research is to carry out estimated and experimental processing of the operating regimes of the regeneration system of steam-turbine plants within the extended adjustment range and under the conditions when the constraints on the regeneration system and its equipment are removed. Constraints concerning the heat balance diagram that reduce the power unit efficiency when extending the adjustment range have been considered. Test results are presented for the nondeaerating heat balance diagram with the HTGZ turbine. Turbine pump and feed electric pump operation was studied at a power unit load of 120-300 MW. The reliability of feed pump operation is confirmed by a stable vibratory condition and the absence of cavitation noise and vibration at a frequency that characterizes the cavitation condition, as well as by oil temperature maintenance after bearings within normal limits. Cavitation performance of pumps in the studied range of their operation has been determined. Technical solutions are proposed on providing a profitable and stable operation of regeneration systems when extending the range of adjustment of power unit load. A nondeaerating diagram of high-pressure preheater (HPP) condensate discharge to the mixer. A regeneration system has been developed and studied on the operating power unit fitted with a deaeratorless thermal circuit of the system for removing the high-pressure preheater heating steam condensate to the mixer

  11. Reduced serum inhibition of platelet-activating factor activity in preeclampsia.

    PubMed

    Benedetto, C; Massobrio, M; Bertini, E; Abbondanza, M; Enrieu, N; Tetta, C

    1989-01-01

    We determined in normal nonpregnant (group 1) women, normal pregnant (group 2) women, and patients with preeclampsia (group 3) the serum inhibition of platelet-activating factor activity, the presence of detectable amounts of platelet-activating factor in the blood, and platelet responsiveness in vitro to platelet-activating factor, and to other agonists (adenosine diphosphate, collagen, and ristocetin), and prostacyclin (prostaglandin I2). In patients with preeclampsia (group 3) the serum inhibition of platelet-activating factor activity was significantly lower than that in groups 1 and 2. However, no detectable amounts of platelet-activating factor were observed. The mean values of platelet aggregation induced by platelet-activating factor, adenosine diphosphate, collagen and ristocetin, and the prostaglandin I2-inhibitory concentration of 50% which is inversely correlated with platelet sensitivity to prostaglandin I2, were not significantly different between groups 2 and 3. It is suggested that in preeclampsia the defect in serum inhibitory potential of platelet-activating factor--induced platelet aggregation may contribute to the disturbance in the homeostatic balance between proaggregant and antiaggregant substances. PMID:2912073

  12. A reduced complexity highly power/bandwidth efficient coded FQPSK system with iterative decoding

    NASA Technical Reports Server (NTRS)

    Simon, M. K.; Divsalar, D.

    2001-01-01

    Based on a representation of FQPSK as a trellis-coded modulation, this paper investigates the potential improvement in power efficiency obtained from the application of simple outer codes to form a concatenated coding arrangement with iterative decoding.

  13. Activation analysis of the PULSAR-II fusion power reactor

    SciTech Connect

    Khater, H.Y.

    1995-12-31

    The PULSAR-II pulsed tokamak power plant design utilizes a blanket made of the vanadium alloy, V-5Cr-5Ti, and cooled with liquid lithium. The shield is made of a mixture of the low activation austenitic steel (Tenelon) and vanadium. The blanket is assumed to be replaced every 5.6 full power years (FPY) and the shield is assumed to stay in place for 30 FPY. The activity induced in the blanket at the end of its lifetime is higher than the activity induced in the shield after 30 FPY. At shutdown, the blanket and shield activities are 2678 MCi and 1747 MCi, respectively. One year after shutdown the shield activity drops to 18 MCi compared to 84 MCi for the blanket. The total decay heat generated in the blanket at the end of its lifetime is 34.7 MW and drops to 17.6 MW within an hour. At shutdown, 25.3 MW of decay heat are generated in the shield, dropping to only 0.1 MW within the first year. One week after shutdown, the values of the integrated decay heat are 1770 GJ for the blanket and 469 GJ for the shield. The radwaste classification of the reactor structure is evaluated according to both the NRC 10CFR61 and Fetter waste disposal concentration limits. After 5.6 years of irradiation, the blanket will only qualify for Class C low level waste. After 30 years of operation, the shield will also qualify for disposal as Class C waste. Only remote maintenance will be allowed inside the containment building.

  14. SIRT1 activating compounds reduce oxidative stress and prevent cell death in neuronal cells

    PubMed Central

    Khan, Reas S.; Fonseca-Kelly, Zoe; Callinan, Catherine; Zuo, Ling; Sachdeva, Mira M.; Shindler, Kenneth S.

    2012-01-01

    Activation of SIRT1, an NAD+-dependent deacetylase, prevents retinal ganglion cell (RGC) loss in optic neuritis, an inflammatory demyelinating optic nerve disease. While SIRT1 deacetylates numerous protein targets, downstream mechanisms of SIRT1 activation mediating this neuroprotective effect are unknown. SIRT1 increases mitochondrial function and reduces oxidative stress in muscle and other cells, and oxidative stress occurs in neuronal degeneration. We examined whether SIRT1 activators reduce oxidative stress and promote mitochondrial function in neuronal cells. Oxidative stress, marked by reactive oxygen species (ROS) accumulation, was induced in RGC-5 cells by serum deprivation, or addition of doxorubicin or hydrogen peroxide, and resulted in significant cell loss. SIRT1 activators resveratrol (RSV) and SRTAW04 reduced ROS levels and promoted cell survival in RGC-5 cells as well as primary RGC cultures. Effects were blocked by SIRT1 siRNA. SIRT1 activators also increased expression of succinate dehydrogenase (SDH), a mitochondrial enzyme, and promoted deacetylation of PGC-1α, a co-enzyme involved in mitochondrial function. Results show SIRT1 activators prevent cell loss by reducing oxidative stress and promoting mitochondrial function in a neuronal cell line. Results suggest SIRT1 activators can mediate neuroprotective effects during optic neuritis by these mechanisms, and they have the potential to preserve neurons in other neurodegenerative diseases that involve oxidative stress. PMID:23293585

  15. Direct observation of enhanced plasmon-driven catalytic reaction activity of Au nanoparticles supported on reduced graphene oxides by SERS.

    PubMed

    Liang, Xiu; You, Tingting; Liu, Dapeng; Lang, Xiufeng; Tan, Enzhong; Shi, Jihua; Yin, Penggang; Guo, Lin

    2015-04-21

    Graphene-based nanocomposites have recently attracted tremendous research interest in the field of catalysis due to their unique optical and electronic properties. However, direct observation of enhanced plasmon-driven catalytic activity of Au nanoparticles (NPs) supported on reduced graphene oxides (Au/rGO) has rarely been reported. Herein, based on the reduction from 4-nitrobenzenethiol (4-NBT) to p,p'-dimercaptoazobenzene (DMAB), the catalytic property of Au/rGO nanocomposites was investigated and compared with corresponding Au NP samples with similar size distribution. Our results show that Au/rGO nanocomposites could serve as a good catalytic and analytic platform for plasmon-driven chemical reactions. In addition, systematic comparisons were conducted during power- and time-dependent surface-enhanced Raman scattering (SERS) experiments, which exhibited a lower power threshold and higher catalytic efficiency for Au/rGO as compared to Au NPs toward the reaction. PMID:25793752

  16. Active control of the resistive wall mode with power saturation

    SciTech Connect

    Li Li; Liu Yue; Liu Yueqiang

    2012-01-15

    An analytic model of non-linear feedback stabilization of the resistive wall mode is presented. The non-linearity comes from either the current or the voltage saturation of the control coil power supply. For the so-called flux-to-current control, the current saturation of active coils always results in the loss of control. On the contrary, the flux-to-voltage control scheme tolerates certain degree of the voltage saturation. The minimal voltage limit is calculated, below which the control will be lost.

  17. Experimental results using active control of traveling wave power flow

    NASA Technical Reports Server (NTRS)

    Miller, David W.; Hall, Steven R.

    1991-01-01

    Active structural control experiments conducted on a 24-ft pinned-free beam derived feedback compensators on the basis of a traveling-wave approach. A compensator is thus obtained which eliminates resonant behavior by absorbing all impinging power. A causal solution is derived for this noncausal compensator which mimics its behavior in a given frequency range, using the Wiener-Hopf. This optimal Wiener-Hopf compensator's structure-damping performance is found to exceed any obtainable by means of rate feedback. Performance limitations encompassed the discovery of frequencies above which the sensor and actuator were no longer dual and an inadvertent coupling of the control hardware to unmodeled structure torsion modes.

  18. Reduced mitochondrial and ascorbate-glutathione activity after artificial ageing in soybean seed.

    PubMed

    Xin, Xia; Tian, Qian; Yin, Guangkun; Chen, Xiaoling; Zhang, Jinmei; Ng, Sophia; Lu, Xinxiong

    2014-01-15

    The effect of artificial ageing on the relationship between mitochondrial activities and the antioxidant system was studied in soybean seeds (Glycine max L. cv. Zhongdou No. 27). Ageing seeds for 18d and 41d at 40°C reduced germination from 99% to 52% and 0%, respectively. In comparison to the control, malondialdehyde content and leachate conductivity in aged seeds increased and were associated with membrane damage. Transmission electron microscopy and Percoll density gradient centrifugation showed that aged seeds mainly contained poorly developed mitochondria in which respiration and marker enzymes activities were significantly reduced. Heavy mitochondria isolated from the interface of the 21% and 40% Percoll were analyzed. Mitochondrial antioxidant enzymes activities including superoxide dismutase, ascorbate peroxidase, glutathione reductase, monodehydroascorbate reductase, and dehydroascorbate reductase were significantly reduced in aged seeds. A decrease in total ascorbic acid (ASC) and glutathione (GSH) content as well as the reduced/oxidized ratio of ASC and GSH in mitochondria with prolonged ageing showed that artificial ageing reduced ASC-GSH cycle activity. These results suggested an elevated reactive oxygen species (ROS) level in the aged seeds, which was confirmed by measurements of superoxide radical and hydrogen peroxide levels. We conclude that mitochondrial dysfunction in artificially aged seeds is due to retarded mitochondrial and ASC-GSH cycle activity and elevated ROS accumulation. PMID:24331429

  19. Impurity effects on reduced-activation ferritic steels developed for fusion applications

    NASA Astrophysics Data System (ADS)

    Klueh, R. L.; Cheng, E. T.; Grossbeck, M. L.; Bloom, E. E.

    2000-08-01

    Reduced-activation steels are being developed for fusion applications by restricting alloying elements that produce long-lived radioactive isotopes when irradiated in the fusion neutron environment. Another source of long-lived isotopes is the impurities in the steel. To examine this, three heats of reduced-activation martensitic steel were analyzed by inductively coupled plasma mass spectrometry for low-level impurities that compromise the reduced-activation characteristics: a 5-ton heat of modified F82H (F82H-Mod) for which an effort was made during production to reduce detrimental impurities, a 1-ton heat of JLF-1, and an 18-kg heat of ORNL 9Cr-2WVTa. Specimens from commercial heats of modified 9Cr-1Mo and Sandvik HT9 were also analyzed. The objective was to determine the difference in the impurity levels in the F82H-Mod and steels for which less effort was used to ensure purity. Silver, molybdenum, and niobium were found to be the tramp impurities of most importance. The F82H-Mod had the lowest levels, but in some cases the levels were not much different from the other heats. The impurity levels in the F82H-Mod produced with present technology did not achieve the low-activation limits for either shallow land burial or recycling. The results indicate the progress that has been made and what still must be done before the reduced-activation criteria can be achieved.

  20. Shape-Dependent Activity of Ceria for Hydrogen Electro-Oxidation in Reduced-Temperature Solid Oxide Fuel Cells.

    PubMed

    Tong, Xiaofeng; Luo, Ting; Meng, Xie; Wu, Hao; Li, Junliang; Liu, Xuejiao; Ji, Xiaona; Wang, Jianqiang; Chen, Chusheng; Zhan, Zhongliang

    2015-11-01

    Single crystalline ceria nanooctahedra, nanocubes, and nanorods are hydrothermally synthesized, colloidally impregnated into the porous La0.9Sr0.1Ga0.8Mg0.2O3-δ (LSGM) scaffolds, and electrochemically evaluated as the anode catalysts for reduced temperature solid oxide fuel cells (SOFCs). Well-defined surface terminations are confirmed by the high-resolution transmission electron microscopy--(111) for nanooctahedra, (100) for nanocubes, and both (110) and (100) for nanorods. Temperature-programmed reduction in H2 shows the highest reducibility for nanorods, followed sequentially by nanocubes and nanooctahedra. Measurements of the anode polarization resistances and the fuel cell power densities reveal different orders of activity of ceria nanocrystals at high and low temperatures for hydrogen electro-oxidation, i.e., nanorods > nanocubes > nanooctahedra at T ≤ 450 °C and nanooctahedra > nanorods > nanocubes at T ≥ 500 °C. Such shape-dependent activities of these ceria nanocrystals have been correlated to their difference in the local structure distortions and thus in the reducibility. These findings will open up a new strategy for design of advanced catalysts for reduced-temperature SOFCs by elaborately engineering the shape of nanocrystals and thus selectively exposing the crystal facets. PMID:26307555

  1. Observational signatures of galactic winds powered by active galactic nuclei

    NASA Astrophysics Data System (ADS)

    Nims, Jesse; Quataert, Eliot; Faucher-Giguère, Claude-André

    2015-03-01

    We predict the observational signatures of galaxy scale outflows powered by active galactic nuclei (AGN). Most of the emission is produced by the forward shock driven into the ambient interstellar medium (ISM) rather than by the reverse shock. AGN-powered galactic winds with energetics suggested by phenomenological feedback arguments should produce spatially extended ˜1-10 keV X-ray emission ˜ 1041-44 erg s- 1, significantly in excess of the spatially extended X-ray emission associated with normal star-forming galaxies. The presence of such emission is a direct test of whether AGN outflows significantly interact with the ISM of their host galaxy. We further show that even radio-quiet quasars should have a radio luminosity comparable to or in excess of the far-infrared-radio correlation of normal star-forming galaxies. This radio emission directly constrains the total kinetic energy flux in AGN-powered galactic winds. Radio emission from AGN wind shocks can also explain the recently highlighted correlations between radio luminosity and the kinematics of AGN narrow-line regions in radio-quiet quasars.

  2. Polarizability of the active site of cytochrome c reduces the activation barrier for electron transfer.

    PubMed

    Dinpajooh, Mohammadhasan; Martin, Daniel R; Matyushov, Dmitry V

    2016-01-01

    Enzymes in biology's energy chains operate with low energy input distributed through multiple electron transfer steps between protein active sites. The general challenge of biological design is how to lower the activation barrier without sacrificing a large negative reaction free energy. We show that this goal is achieved through a large polarizability of the active site. It is polarized by allowing a large number of excited states, which are populated quantum mechanically by electrostatic fluctuations of the protein and hydration water shells. This perspective is achieved by extensive mixed quantum mechanical/molecular dynamics simulations of the half reaction of reduction of cytochrome c. The barrier for electron transfer is consistently lowered by increasing the number of excited states included in the Hamiltonian of the active site diagonalized along the classical trajectory. We suggest that molecular polarizability, in addition to much studied electrostatics of permanent charges, is a key parameter to consider in order to understand how enzymes work. PMID:27306204

  3. Polarizability of the active site of cytochrome c reduces the activation barrier for electron transfer

    NASA Astrophysics Data System (ADS)

    Dinpajooh, Mohammadhasan; Martin, Daniel R.; Matyushov, Dmitry V.

    2016-06-01

    Enzymes in biology’s energy chains operate with low energy input distributed through multiple electron transfer steps between protein active sites. The general challenge of biological design is how to lower the activation barrier without sacrificing a large negative reaction free energy. We show that this goal is achieved through a large polarizability of the active site. It is polarized by allowing a large number of excited states, which are populated quantum mechanically by electrostatic fluctuations of the protein and hydration water shells. This perspective is achieved by extensive mixed quantum mechanical/molecular dynamics simulations of the half reaction of reduction of cytochrome c. The barrier for electron transfer is consistently lowered by increasing the number of excited states included in the Hamiltonian of the active site diagonalized along the classical trajectory. We suggest that molecular polarizability, in addition to much studied electrostatics of permanent charges, is a key parameter to consider in order to understand how enzymes work.

  4. Polarizability of the active site of cytochrome c reduces the activation barrier for electron transfer

    PubMed Central

    Dinpajooh, Mohammadhasan; Martin, Daniel R.; Matyushov, Dmitry V.

    2016-01-01

    Enzymes in biology’s energy chains operate with low energy input distributed through multiple electron transfer steps between protein active sites. The general challenge of biological design is how to lower the activation barrier without sacrificing a large negative reaction free energy. We show that this goal is achieved through a large polarizability of the active site. It is polarized by allowing a large number of excited states, which are populated quantum mechanically by electrostatic fluctuations of the protein and hydration water shells. This perspective is achieved by extensive mixed quantum mechanical/molecular dynamics simulations of the half reaction of reduction of cytochrome c. The barrier for electron transfer is consistently lowered by increasing the number of excited states included in the Hamiltonian of the active site diagonalized along the classical trajectory. We suggest that molecular polarizability, in addition to much studied electrostatics of permanent charges, is a key parameter to consider in order to understand how enzymes work. PMID:27306204

  5. Hepcidin bound to α2-macroglobulin reduces ferroportin-1 expression and enhances its activity at reducing serum iron levels.

    PubMed

    Huang, Michael Li-Hsuan; Austin, Christopher J D; Sari, Marie-Agnès; Rahmanto, Yohan Suryo; Ponka, Prem; Vyoral, Daniel; Richardson, Des R

    2013-08-30

    Hepcidin regulates iron metabolism by down-regulating ferroportin-1 (Fpn1). We demonstrated that hepcidin is complexed to the blood transport protein, α2-macroglobulin (α2M) (Peslova, G., Petrak, J., Kuzelova, K., Hrdy, I., Halada, P., Kuchel, P. W., Soe-Lin, S., Ponka, P., Sutak, R., Becker, E., Huang, M. L., Suryo Rahmanto, Y., Richardson, D. R., and Vyoral, D. (2009) Blood 113, 6225-6236). However, nothing is known about the mechanism of hepcidin binding to α2M or the effects of the α2M·hepcidin complex in vivo. We show that decreased Fpn1 expression can be mediated by hepcidin bound to native α2M and also, for the first time, hepcidin bound to methylamine-activated α2M (α2M-MA). Passage of high molecular weight α2M·hepcidin or α2M-MA·hepcidin complexes (≈725 kDa) through a Sephadex G-25 size exclusion column retained their ability to decrease Fpn1 expression. Further studies using ultrafiltration indicated that hepcidin binding to α2M and α2M-MA was labile, resulting in some release from the protein, and this may explain its urinary excretion. To determine whether α2M-MA·hepcidin is delivered to cells via the α2M receptor (Lrp1), we assessed α2M uptake and Fpn1 expression in Lrp1(-/-) and Lrp1(+/+) cells. Interestingly, α2M·hepcidin or α2M-MA·hepcidin demonstrated similar activities at decreasing Fpn1 expression in Lrp1(-/-) and Lrp1(+/+) cells, indicating that Lrp1 is not essential for Fpn1 regulation. In vivo, hepcidin bound to α2M or α2M-MA did not affect plasma clearance of α2M/α2M-MA. However, serum iron levels were reduced to a significantly greater extent in mice treated with α2M·hepcidin or α2M-MA·hepcidin relative to unbound hepcidin. This effect could be mediated by the ability of α2M or α2M-MA to retard kidney filtration of bound hepcidin, increasing its half-life. A model is proposed that suggests that unlike proteases, which are irreversibly bound to activated α2M, hepcidin remains labile and available to down

  6. Metal clad active fibres for power scaling and thermal management at kW power levels.

    PubMed

    Daniel, Jae M O; Simakov, Nikita; Hemming, Alexander; Clarkson, W Andrew; Haub, John

    2016-08-01

    We present a new approach to high power fibre laser design, consisting of a polymer-free all-glass optical fibre waveguide directly overclad with a high thermal conductivity metal coating. This metal clad active fibre allows a significant reduction in thermal resistance between the active fibre and the laser heat-sink as well as a significant increase in the operating temperature range. In this paper we show the results of a detailed thermal analysis of both polymer and metal coated active fibres under thermal loads typical of kW fibre laser systems. Through several different experiments we present the first demonstration of a cladding pumped aluminium-coated fibre laser and the first demonstration of efficient operation of a cladding-pumped fibre laser at temperatures of greater than 400 °C. Finally, we highlight the versatility of this approach through operation of a passively (radiatively) cooled ytterbium fibre laser head at an output power of 405 W in a compact and ultralight package weighing less than 100 g. PMID:27505822

  7. 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.

  8. Design of high-power aspherical ophthalmic lenses with a reduced error budget

    NASA Astrophysics Data System (ADS)

    Sun, Wen-Shing; Chang, Horng; Sun, Ching-Cherng; Chang, Ming-Wen; Lin, Ching-Huang; Tien, Chuen-Lin

    2002-02-01

    As in the lens optimization process, ophthalmic lens designers have usually constructed error functions with 0.5, 0.7, and 1.0 at only three oblique fields. This seems enough to achieve a balanced trade-off with the astigmatic error, the power error, and the distortion all being considered simultaneously. However, for high-power ophthalmic lenses, the aberration curves show serious violations even if aspherical coefficients are involved. The analytical results indicate that a field error suppression of up to 7 points may even be required in some cases. The suppression effects are excellent and examples of both positive and negative lenses are designed.

  9. Cross-person activity recognition using reduced kernel extreme learning machine.

    PubMed

    Deng, Wan-Yu; Zheng, Qing-Hua; Wang, Zhong-Min

    2014-05-01

    Activity recognition based on mobile embedded accelerometer is very important for developing human-centric pervasive applications such as healthcare, personalized recommendation and so on. However, the distribution of accelerometer data is heavily affected by varying users. The performance will degrade when the model trained on one person is used to others. To solve this problem, we propose a fast and accurate cross-person activity recognition model, known as TransRKELM (Transfer learning Reduced Kernel Extreme Learning Machine) which uses RKELM (Reduced Kernel Extreme Learning Machine) to realize initial activity recognition model. In the online phase OS-RKELM (Online Sequential Reduced Kernel Extreme Learning Machine) is applied to update the initial model and adapt the recognition model to new device users based on recognition results with high confidence level efficiently. Experimental results show that, the proposed model can adapt the classifier to new device users quickly and obtain good recognition performance. PMID:24513850

  10. Occurrence and activity of sulphate reducing bacteria in aerobic activated sludge systems.

    PubMed

    van den Brand, T P H; Roest, K; Chen, G H; Brdjanovic, D; van Loosdrecht, M C M

    2015-03-01

    In the sewage or wastewater treatment plant, biological sulphate reduction can occur spontaneously or be applied beneficially for its treatment. The results of this study can be applied to control SRB in the sewage and WWTP. Therefore, population diversity analyses of SRB for nine activated sludge wastewater treatment plants (WWTP) in the Netherlands and the effect of long-term (months) oxygen exposures on the SRB activity were carried out. T-RFLP and clone sequencing analyses of winter and summer samples revealed that (1) all WWTP have a similar SRB population, (2) there is no seasonal impact (10-20 °C) on the SRB population present in the WWTP and (3) Desulfobacter postgatei, Desulfovibrio desulfuricans and Desulfovibrio intestinalis were the most common and dominant SRB species observed in these samples, and origin from the sewage. Short term activity tests demonstrated that SRB were not active in the aerobic WWTP, but while flushed with N2-gas SRB became slightly active after 3 h. In a laboratory reactor at a dissolved oxygen concentration of <2 %, sulphate reduction occurred and 89 % COD removal was achieved. SRB grew in granules, in order to protect themselves for oxygen exposures. SRB are naturally present in aerobic WWTP, which is due to the formation of granules. PMID:25649202

  11. Polyphenols from Chilean Propolis and Pinocembrin Reduce MMP-9 Gene Expression and Activity in Activated Macrophages

    PubMed Central

    Saavedra, Nicolás; Cuevas, Alejandro; Cavalcante, Marcela F.; Dörr, Felipe A.; Saavedra, Kathleen; Zambrano, Tomás; Abdalla, Dulcineia S. P.; Salazar, Luis A.

    2016-01-01

    Polyphenols from diverse sources have shown anti-inflammatory activity. In the context of atherosclerosis, macrophages play important roles including matrix metalloproteinases synthesis involved in degradation of matrix extracellular components affecting the atherosclerotic plaque stability. We prepared a propolis extract and pinocembrin in ethanol solution. Propolis extract was chemically characterized using LC-MS. The effect of treatments on gene expression and proteolytic activity was measured in vitro using murine macrophages activated with LPS. Cellular toxicity associated with both treatments and the vehicle was determined using MTT and apoptosis/necrosis detection assays. MMP-9 gene expression and proteolytic activity were measured using qPCR and zymography, respectively. Thirty-two compounds were identified in the propolis extract, including pinocembrin among its major components. Treatment with either ethanolic extract of propolis or pinocembrin inhibits MMP-9 gene expression in a dose-dependent manner. Similarly, an inhibitory effect was observed in proteolytic activity. However, the effect showed by ethanolic extract of propolis was higher than the effect of pinocembrin, suggesting that MMP-9 inhibition results from a joint contribution between the components of the extract. These data suggest a potential role of polyphenols from Chilean propolis in the control of extracellular matrix degradation in atherosclerotic plaques. PMID:27119082

  12. Monitoring Statistics Which Have Increased Power over a Reduced Time Range.

    ERIC Educational Resources Information Center

    Tang, S. M.; MacNeill, I. B.

    1992-01-01

    The problem of monitoring trends for changes at unknown times is considered. Statistics that permit one to focus high power on a segment of the monitored period are studied. Numerical procedures are developed to compute the null distribution of these statistics. (Author)

  13. Differential responses of nitrate reducer community size, structure, and activity to tillage systems.

    PubMed

    Chèneby, D; Brauman, A; Rabary, B; Philippot, L

    2009-05-01

    The main objective of this study was to determine how the size, structure, and activity of the nitrate reducer community were affected by adoption of a conservative tillage system as an alternative to conventional tillage. The experimental field, established in Madagascar in 1991, consists of plots subjected to conventional tillage or direct-seeding mulch-based cropping systems (DM), both amended with three different fertilization regimes. Comparisons of size, structure, and activity of the nitrate reducer community in samples collected from the top layer in 2005 and 2006 revealed that all characteristics of this functional community were affected by the tillage system, with increased nitrate reduction activity and numbers of nitrate reducers under DM. Nitrate reduction activity was also stimulated by combined organic and mineral fertilization but not by organic fertilization alone. In contrast, both negative and positive effects of combined organic and mineral fertilization on the size of the nitrate reducer community were observed. The size of the nitrate reducer community was a significant predictor of the nitrate reduction rates except in one treatment, which highlighted the inherent complexities in understanding the relationships the between size, diversity, and structure of functional microbial communities along environmental gradients. PMID:19304827

  14. Differential Responses of Nitrate Reducer Community Size, Structure, and Activity to Tillage Systems▿ †

    PubMed Central

    Chèneby, D.; Brauman, A.; Rabary, B.; Philippot, L.

    2009-01-01

    The main objective of this study was to determine how the size, structure, and activity of the nitrate reducer community were affected by adoption of a conservative tillage system as an alternative to conventional tillage. The experimental field, established in Madagascar in 1991, consists of plots subjected to conventional tillage or direct-seeding mulch-based cropping systems (DM), both amended with three different fertilization regimes. Comparisons of size, structure, and activity of the nitrate reducer community in samples collected from the top layer in 2005 and 2006 revealed that all characteristics of this functional community were affected by the tillage system, with increased nitrate reduction activity and numbers of nitrate reducers under DM. Nitrate reduction activity was also stimulated by combined organic and mineral fertilization but not by organic fertilization alone. In contrast, both negative and positive effects of combined organic and mineral fertilization on the size of the nitrate reducer community were observed. The size of the nitrate reducer community was a significant predictor of the nitrate reduction rates except in one treatment, which highlighted the inherent complexities in understanding the relationships the between size, diversity, and structure of functional microbial communities along environmental gradients. PMID:19304827

  15. Comparison of two methods for assaying reducing sugars in the determination of carbohydrase activities.

    PubMed

    Gusakov, Alexander V; Kondratyeva, Elena G; Sinitsyn, Arkady P

    2011-01-01

    The Nelson-Somogyi (NS) and 3,5-dinitrosalicylic acid (DNS) assays for reducing sugars are widely used in measurements of carbohydrase activities against different polysaccharides. Using twelve commercial enzyme preparations, the comparison of the NS and DNS assays in determination of cellulase, β-glucanase, xylanase, and β-mannanase activities was carried out. When cellulase activities against CMC were measured, the DNS assay gave activity values, which were typically 40-50% higher than those obtained with the NS assay. In the analysis of the xylanase, β-mannanase, and β-glucanase activities, the overestimations by the DNS assay were much more pronounced (the observed differences in the activities were 3- to 13-fold). Reasons for preferential use of the NS assay for measuring activities of carbohydrases other than cellulases are discussed. PMID:21647284

  16. Harmonic and power factor correction by means of active line conditioners with adaptive estimation control

    SciTech Connect

    Ashton, R.W.

    1991-01-01

    Due to the proliferation of power electronic devices in recent years, the amount of harmonic current injected into power systems is on the increase causing undesirable voltage waveform distortion. A new type of versatile Active Power Line Conditioner able to supply a DC load while generating useful harmonics which help reduce the voltage distortion at the connected bus was designed, built and analyzed. The optimum design was obtained by means of an economic study that considers the power loss, the cost of an RFI filter and the effect of the switching rate. An adaptive methodology, requiring only knowledge of the bus voltage distortion, was developed and applied to adjust the amplitudes and phase angles of the injected harmonic currents. This novel approach is based on reducing the voltage Total Harmonic Distortion by minimizing the individual harmonic voltages in an error signal using a gradient method. Through successive adjustments, the difference between the actual bus voltage and the desired bus voltage is minimized. The proposed method can be successfully applied in low and medium voltage networks with multiple nonlinear loads scattered among linear loads.

  17. Prospective active marker motion correction improves statistical power in BOLD fMRI

    PubMed Central

    Ooi, Melvyn B.; Goldman, Robin I.; Krueger, Sascha; Thomas, William J.; Sajda, Paul; Brown, Truman R.

    2013-01-01

    Group level statistical maps of blood oxygenation level dependent (BOLD) signals acquired using functional magnetic resonance imaging (fMRI) have become a basic measurement for much of systems, cognitive and social neuroscience. A challenge in making inferences from these statistical maps is the noise and potential confounds that arise from the head motion that occurs within and between acquisition volumes. This motion results in the scan plane being misaligned during acquisition, ultimately leading to reduced statistical power when maps are constructed at the group level. In most cases, an attempt is made to correct for this motion through the use of retrospective analysis methods. In this paper, we use a prospective active marker motion correction (PRAMMO) system that uses radio frequency markers for real-time tracking of motion, enabling on-line slice plane correction. We show that the statistical power of the activation maps is substantially increased using PRAMMO compared to conventional retrospective correction. Analysis of our results indicates that the PRAMMO acquisition reduces the variance without decreasing the signal component of the BOLD (beta). Using PRAMMO could thus improve the overall statistical power of fMRI based BOLD measurements, leading to stronger inferences of the nature of processing in the human brain. PMID:23220430

  18. Generation of reducing power in chemosynthesis. 3. Energy-linked reduction of pyridine nucleotides in Thiobacillus novellus.

    PubMed

    Aleem, M I

    1966-02-01

    Aleem, M. I. H. (Research Institute for Advanced Studies, Baltimore, Md.). Generation of reducing power in chemosynthesis. III. Energy-linked reduction of pyridine nucleotides in Thiobacillus novellus. J. Bacteriol. 91:729-736. 1966.-Cell-free extracts from Thiobacillus novellus. catalyzed an adenosine triphosphate (ATP)-dependent reduction of pyridine nucleotides anaerobically, or aerobically when the respiratory chain was inhibited by azide. The exogenous electron donor employed for the reduction of nicotinamide adenine dinucleotide or nicotinamide adenine dinucleotide phosphate (NADP) was thiosulfate, formate, or mammalian ferrocytochrome c. In the latter case, the oxidation of ferrocytochrome c was observed with the concomitant reduction of the pyridine nucleotide. Values calculated for the molar ratios of ATP utilized-NADP reduced and of cytochrome c oxidized-NADP reduced were 1:1 and 2:1, respectively. The energy-dependent reduction of the pyridine nucleotides was inhibited by Atabrine or amytal and by low concentrations of the uncouplers of oxidative phosphorylation such as 2,4-dinitrophenol and carbonyl cyanide m-chlorophenyl hydrazone. Evidence is presented showing that the reduced pyridine nucleotides are essential for providing the reducing power for the energy-dependent reduction of carbon dioxide in T. novellus. PMID:4379907

  19. Evaluation of in vitro urease and lipoxygenase inhibition activity of weight reducing tablets.

    PubMed

    Jaffary, Syed Rashid Ali; Ahmed, Syed Waseemuddin; Shakeel, Sadia; Asif, Hafiz Muhammad; Usmanghani, Khan

    2016-07-01

    Enzyme inhibition is a significant part of research in pharmaceutical field in view of the fact that these studies have directed to the innovations of drugs having remarkable performance in diverse physiological conditions. The present study was aimed to assess urease and lipoxygenase inhibitory activity of weight reducing tablets. For evaluating the urease activity indophenol method was employed using Thiourea as the model urease inhibitor. The lipoxygenase inhibition was evaluated by measuring the hydroperoxides produced in lipoxygenation reaction using a purified lipoxygenase with lionoleic acid as substrate. When formulation of the weight reducing tablets was compared at various concentrations (50, 100 and 500µg/ml). The antiurease activity and lipoxygenase inhibition activity increased in a dose dependent manner. The formulations under test have an excellent antiurease and lipoxygenase inhibition potential and prospective to be used in the cure of a variety of complications associated with the production of urease and lipoxygenase enzymes. PMID:27592490

  20. Assessment of xylanase activity in dry storage as a potential method of reducing feedstock cost.

    PubMed

    Smith, William A; Thompson, David N; Thompson, Vicki S; Radtke, Corey W; Carter, Brady

    2009-05-01

    Enzymatic preprocessing of lignocellulosic biomass in dry storage systems has the potential to improve feedstock characteristics and lower ethanol production costs. To assess the potential for endoxylanase activity at low water contents, endoxylanase activity was tested using a refined wheat arabinoxylan substrate and three commercial endoxylanases over the water activity range 0.21-1.0, corresponding to water contents of 5% to >60% (dry basis). Homogeneously mixed dry samples were prepared at a fixed enzyme to substrate ratio and incubated in chambers at a variety of fixed water activities. Replicates were sacrificed periodically, and endoxylanase activity was quantified as an increase in reducing sugar relative to desiccant-stored controls. Endoxylanase activity was observed at water activities over 0.91 in all enzyme preparations in less than 4 days and at a water activity of 0.59 in less than 1 week in two preparations. Endoxylanase activity after storage was confirmed for selected desiccant-stored controls by incubation at 100% relative humidity. Water content to water activity relationships were determined for three lignocellulosic substrates, and results indicate that two endoxylanase preparations retained limited activity as low as 7% to 13% water content (dry basis), which is well within the range of water contents representative of dry biomass storage. Future work will examine the effects of endoxylanase activity toward substrates such as corn stover, wheat straw, and switchgrass in low water content environments. PMID:19096939

  1. Bang without the buck? Bypassing merger, four systems look for buying power, reduced costs with collaboration.

    PubMed

    Kutscher, Beth

    2012-10-29

    Four not-for-profit systems are banding together in an arrangement that falls short of a merger but aims to increase the partners' buying power. "We favor the idea of local control and local governance. It's not financial because we've had as good a financial year as we've had in a decade," says Steven Edwards, president and CEO of CoxHealth. PMID:23227664

  2. Extensive sugar modification improves triple helix forming oligonucleotide activity in vitro but reduces activity in vivo.

    PubMed

    Alam, Md Rowshon; Majumdar, Alokes; Thazhathveetil, Arun Kalliat; Liu, Su-Ting; Liu, Ji-Lan; Puri, Nitin; Cuenoud, Bernard; Sasaki, Shigeki; Miller, Paul S; Seidman, Michael M

    2007-09-01

    We are developing triple helix forming oligonucleotides (TFOs) for gene targeting. Previously, we synthesized bioactive TFOs containing 2'-O-methylribose (2'-OMe) and 2'-O-aminoethylribose (2'-AE) residues. Active TFOs contained four contiguous 2'-AE residues and formed triplexes with high thermal stability and rapid association kinetics. In an effort to further improve bioactivity, we synthesized three series of TFOs containing the 2'-AE patch and additional ribose modifications distributed throughout the remainder of the oligonucleotide. These were either additional 2'-AE residues, the conformationally locked BNA/LNA ribose with a 2'-O,4'-C-methylene bridge, or the 2'-O,4'-C-ethylene analogue (ENA). The additionally modified TFOs formed triplexes with greater thermal stability than the reference TFO, and some had improved association kinetics. However, the most active TFOs in the biochemical and biophysical assays were the least active in the bioassay. We measured the thermal stability of triplexes formed by the TFOs in each series on duplex targets containing a change in sequence at a single position. The Tm value of the variant sequence triplexes increased as the number of all additional modifications increased. A simple explanation for the failure of the improved TFOs in the bioassay was that the increased affinity for nonspecific targets lowered the effective nuclear concentration. Enhancement of TFO bioactivity will require chemical modifications that improve interaction with the specific targets while retaining selectivity against mismatched sequences. PMID:17691818

  3. One order of magnitude faster phase change at reduced power in Ti-Sb-Te

    PubMed Central

    Zhu, Min; Xia, Mengjiao; Rao, Feng; Li, Xianbin; Wu, Liangcai; Ji, Xinglong; Lv, Shilong; Song, Zhitang; Feng, Songlin; Sun, Hongbo; Zhang, Shengbai

    2014-01-01

    To date, slow Set operation speed and high Reset operation power remain to be important limitations for substituting dynamic random access memory by phase change memory. Here, we demonstrate phase change memory cell based on Ti0.4Sb2Te3 alloy, showing one order of magnitude faster Set operation speed and as low as one-fifth Reset operation power, compared with Ge2Sb2Te5-based phase change memory cell at the same size. The enhancements may be rooted in the common presence of titanium-centred octahedral motifs in both amorphous and crystalline Ti0.4Sb2Te3 phases. The essentially unchanged local structures around the titanium atoms may be responsible for the significantly improved performance, as these structures could act as nucleation centres to facilitate a swift, low-energy order-disorder transition for the rest of the Sb-centred octahedrons. Our study may provide an alternative to the development of high-speed, low-power dynamic random access memory-like phase change memory technology. PMID:25001009

  4. One order of magnitude faster phase change at reduced power in Ti-Sb-Te.

    PubMed

    Zhu, Min; Xia, Mengjiao; Rao, Feng; Li, Xianbin; Wu, Liangcai; Ji, Xinglong; Lv, Shilong; Song, Zhitang; Feng, Songlin; Sun, Hongbo; Zhang, Shengbai

    2014-01-01

    To date, slow Set operation speed and high Reset operation power remain to be important limitations for substituting dynamic random access memory by phase change memory. Here, we demonstrate phase change memory cell based on Ti0.4Sb2Te3 alloy, showing one order of magnitude faster Set operation speed and as low as one-fifth Reset operation power, compared with Ge2Sb2Te5-based phase change memory cell at the same size. The enhancements may be rooted in the common presence of titanium-centred octahedral motifs in both amorphous and crystalline Ti0.4Sb2Te3 phases. The essentially unchanged local structures around the titanium atoms may be responsible for the significantly improved performance, as these structures could act as nucleation centres to facilitate a swift, low-energy order-disorder transition for the rest of the Sb-centred octahedrons. Our study may provide an alternative to the development of high-speed, low-power dynamic random access memory-like phase change memory technology. PMID:25001009

  5. Reduced heat stress in offices in the tropics using solar powered drying of the supply air.

    PubMed

    Gunnarsen, L; Santos, A M B

    2002-12-01

    Many solutions to indoor climate problems known from developed countries may have prohibitive installation and running costs in developing countries. The purpose was to develop a low-cost solution to heat stress in a hot and humid environment based on solar powered drying of supply air. Dry supply air may facilitate personal cooling by increased evaporation of sweat. Heat acclimatized people with efficient sweating may in particular benefit from this cooling. A prototype solar powered supply system for dried-only air was made. Air from the system was mixed with room air, heated to six different combinations of temperature and humidity and led to Personal Units for Ventilation and Cooling (PUVAC) in six cubicles simulating office workplaces. A total of 123 heat acclimatized subjects were exposed 45 min in each of the cubicles. A model for the combined effect of operative temperature of room, moisture content of room air, temperature of supply air and moisture content of supply air was developed based on the experiments. Reduction of moisture content in the supply air by 1.6 g/kg had the same effect as lowering the operative temperature by 1 degree C. The solar-powered system for supplying dry air is a low-cost alternative to traditional air conditioning in hot and humid regions. PMID:12532757

  6. Using architecture information and real-time resource state to reduce power consumption and communication costs in parallel applications.

    SciTech Connect

    Brandt, James M.; Devine, Karen Dragon; Gentile, Ann C.; Leung, Vitus Joseph; Olivier, Stephen Lecler; Pedretti, Kevin; Rajamanickam, Sivasankaran; Bunde, David P.; Deveci, Mehmet; Catalyurek, Umit V.

    2014-09-01

    As computer systems grow in both size and complexity, the need for applications and run-time systems to adjust to their dynamic environment also grows. The goal of the RAAMP LDRD was to combine static architecture information and real-time system state with algorithms to conserve power, reduce communication costs, and avoid network contention. We devel- oped new data collection and aggregation tools to extract static hardware information (e.g., node/core hierarchy, network routing) as well as real-time performance data (e.g., CPU uti- lization, power consumption, memory bandwidth saturation, percentage of used bandwidth, number of network stalls). We created application interfaces that allowed this data to be used easily by algorithms. Finally, we demonstrated the benefit of integrating system and application information for two use cases. The first used real-time power consumption and memory bandwidth saturation data to throttle concurrency to save power without increasing application execution time. The second used static or real-time network traffic information to reduce or avoid network congestion by remapping MPI tasks to allocated processors. Results from our work are summarized in this report; more details are available in our publications [2, 6, 14, 16, 22, 29, 38, 44, 51, 54].

  7. Development of Advanced Technologies to Reduce Design, Fabrication and Construction Costs for Future Nuclear Power Plants

    SciTech Connect

    DiNunzio, Camillo A.; Gupta, Abhinav; Golay, Michael; Luk, Vincent; Turk, Rich; Morrow, Charles; Jin, Geum-Taek

    2002-11-30

    This report presents a summation of the third and final year of a three-year investigation into methods and technologies for substantially reducing the capital costs and total schedule for future nuclear plants. In addition, this is the final technical report for the three-year period of studies.

  8. Harnessing the Power of Perception: Reducing Alcohol-Related Harm among Rural Teenagers

    ERIC Educational Resources Information Center

    Hughes, Clarissa; Julian, Roberta; Richman, Matthew; Mason, Ron; Long, Gillian

    2008-01-01

    This paper outlines early findings from the Tasmanian-based Social Norms Analysis Project (SNAP). The Social Norms model is presented as a theoretically informed, evidence-based model for reducing alcohol-related harm in youthful populations by utilising the complex and often positive contributions peer groups make to adolescent health and…

  9. Reduced In-Plane, Low Frequency Helicopter Noise of an Active Flap Rotor

    NASA Technical Reports Server (NTRS)

    Sim, Ben W.; Janakiram, Ram D.; Barbely, Natasha L.; Solis, Eduardo

    2009-01-01

    Results from a recent joint DARPA/Boeing/NASA/Army wind tunnel test demonstrated the ability to reduce in-plane, low frequency noise of the full-scale Boeing-SMART rotor using active flaps. Test data reported in this paper illustrated that acoustic energy in the first six blade-passing harmonics could be reduced by up to 6 decibels at a moderate airspeed, level flight condition corresponding to advance ratio of 0.30. Reduced noise levels were attributed to selective active flap schedules that modified in-plane blade airloads on the advancing side of the rotor, in a manner, which generated counteracting acoustic pulses that partially offset the negative pressure peaks associated with in-plane, steady thickness noise. These favorable reduced-noise operating states are a strong function of the active flap actuation amplitude, frequency and phase. The associated noise reductions resulted in reduced aural detection distance by up to 18%, but incurred significant vibratory load penalties due to increased hub shear forces. Small reductions in rotor lift-to-drag ratios, of no more than 3%, were also measured

  10. High salt reduces the activation of IL-4- and IL-13-stimulated macrophages.

    PubMed

    Binger, Katrina J; Gebhardt, Matthias; Heinig, Matthias; Rintisch, Carola; Schroeder, Agnes; Neuhofer, Wolfgang; Hilgers, Karl; Manzel, Arndt; Schwartz, Christian; Kleinewietfeld, Markus; Voelkl, Jakob; Schatz, Valentin; Linker, Ralf A; Lang, Florian; Voehringer, David; Wright, Mark D; Hubner, Norbert; Dechend, Ralf; Jantsch, Jonathan; Titze, Jens; Müller, Dominik N

    2015-11-01

    A high intake of dietary salt (NaCl) has been implicated in the development of hypertension, chronic inflammation, and autoimmune diseases. We have recently shown that salt has a proinflammatory effect and boosts the activation of Th17 cells and the activation of classical, LPS-induced macrophages (M1). Here, we examined how the activation of alternative (M2) macrophages is affected by salt. In stark contrast to Th17 cells and M1 macrophages, high salt blunted the alternative activation of BM-derived mouse macrophages stimulated with IL-4 and IL-13, M(IL-4+IL-13) macrophages. Salt-induced reduction of M(IL-4+IL-13) activation was not associated with increased polarization toward a proinflammatory M1 phenotype. In vitro, high salt decreased the ability of M(IL-4+IL-13) macrophages to suppress effector T cell proliferation. Moreover, mice fed a high salt diet exhibited reduced M2 activation following chitin injection and delayed wound healing compared with control animals. We further identified a high salt-induced reduction in glycolysis and mitochondrial metabolic output, coupled with blunted AKT and mTOR signaling, which indicates a mechanism by which NaCl inhibits full M2 macrophage activation. Collectively, this study provides evidence that high salt reduces noninflammatory innate immune cell activation and may thus lead to an overall imbalance in immune homeostasis. PMID:26485286

  11. High salt reduces the activation of IL-4– and IL-13–stimulated macrophages

    PubMed Central

    Binger, Katrina J.; Gebhardt, Matthias; Heinig, Matthias; Rintisch, Carola; Schroeder, Agnes; Neuhofer, Wolfgang; Hilgers, Karl; Manzel, Arndt; Schwartz, Christian; Kleinewietfeld, Markus; Voelkl, Jakob; Schatz, Valentin; Linker, Ralf A.; Lang, Florian; Voehringer, David; Wright, Mark D.; Hubner, Norbert; Dechend, Ralf; Jantsch, Jonathan; Titze, Jens; Müller, Dominik N.

    2015-01-01

    A high intake of dietary salt (NaCl) has been implicated in the development of hypertension, chronic inflammation, and autoimmune diseases. We have recently shown that salt has a proinflammatory effect and boosts the activation of Th17 cells and the activation of classical, LPS-induced macrophages (M1). Here, we examined how the activation of alternative (M2) macrophages is affected by salt. In stark contrast to Th17 cells and M1 macrophages, high salt blunted the alternative activation of BM-derived mouse macrophages stimulated with IL-4 and IL-13, M(IL-4+IL-13) macrophages. Salt-induced reduction of M(IL-4+IL-13) activation was not associated with increased polarization toward a proinflammatory M1 phenotype. In vitro, high salt decreased the ability of M(IL-4+IL-13) macrophages to suppress effector T cell proliferation. Moreover, mice fed a high salt diet exhibited reduced M2 activation following chitin injection and delayed wound healing compared with control animals. We further identified a high salt–induced reduction in glycolysis and mitochondrial metabolic output, coupled with blunted AKT and mTOR signaling, which indicates a mechanism by which NaCl inhibits full M2 macrophage activation. Collectively, this study provides evidence that high salt reduces noninflammatory innate immune cell activation and may thus lead to an overall imbalance in immune homeostasis. PMID:26485286

  12. A Reduced-Order Model of Transport Phenomena for Power Plant Simulation

    SciTech Connect

    Paul Cizmas; Brian Richardson; Thomas Brenner; Raymond Fontenot

    2009-09-30

    A reduced-order model based on proper orthogonal decomposition (POD) has been developed to simulate transient two- and three-dimensional isothermal and non-isothermal flows in a fluidized bed. Reduced-order models of void fraction, gas and solids temperatures, granular energy, and z-direction gas and solids velocity have been added to the previous version of the code. These algorithms are presented and their implementation is discussed. Verification studies are presented for each algorithm. A number of methods to accelerate the computations performed by the reduced-order model are presented. The errors associated with each acceleration method are computed and discussed. Using a combination of acceleration methods, a two-dimensional isothermal simulation using the reduced-order model is shown to be 114 times faster than using the full-order model. In the pursue of achieving the objectives of the project and completing the tasks planned for this program, several unplanned and unforeseen results, methods and studies have been generated. These additional accomplishments are also presented and they include: (1) a study of the effect of snapshot sampling time on the computation of the POD basis functions, (2) an investigation of different strategies for generating the autocorrelation matrix used to find the POD basis functions, (3) the development and implementation of a bubble detection and tracking algorithm based on mathematical morphology, (4) a method for augmenting the proper orthogonal decomposition to better capture flows with discontinuities, such as bubbles, and (5) a mixed reduced-order/full-order model, called point-mode proper orthogonal decomposition, designed to avoid unphysical due to approximation errors. The limitations of the proper orthogonal decomposition method in simulating transient flows with moving discontinuities, such as bubbling flows, are discussed and several methods are proposed to adapt the method for future use.

  13. Active Vibration Control for Helicopter Interior Noise Reduction Using Power Minimization

    NASA Technical Reports Server (NTRS)

    Mendoza, J.; Chevva, K.; Sun, F.; Blanc, A.; Kim, S. B.

    2014-01-01

    This report describes work performed by United Technologies Research Center (UTRC) for NASA Langley Research Center (LaRC) under Contract NNL11AA06C. The objective of this program is to develop technology to reduce helicopter interior noise resulting from multiple gear meshing frequencies. A novel active vibration control approach called Minimum Actuation Power (MAP) is developed. MAP is an optimal control strategy that minimizes the total input power into a structure by monitoring and varying the input power of controlling sources. MAP control was implemented without explicit knowledge of the phasing and magnitude of the excitation sources by driving the real part of the input power from the controlling sources to zero. It is shown that this occurs when the total mechanical input power from the excitation and controlling sources is a minimum. MAP theory is developed for multiple excitation sources with arbitrary relative phasing for single or multiple discrete frequencies and controlled by a single or multiple controlling sources. Simulations and experimental results demonstrate the feasibility of MAP for structural vibration reduction of a realistic rotorcraft interior structure. MAP control resulted in significant average global vibration reduction of a single frequency and multiple frequency excitations with one controlling actuator. Simulations also demonstrate the potential effectiveness of the observed vibration reductions on interior radiated noise.

  14. Reduced Nav1.6 Sodium Channel Activity in Mice Increases In Vivo Sensitivity to Volatile Anesthetics

    PubMed Central

    Pal, Dinesh; Jones, Julie M.; Wisidagamage, Stella

    2015-01-01

    Nav1.6 is a major voltage-gated sodium channel in the central and peripheral nervous systems. Within neurons, the channel protein is concentrated at the axon initial segment and nodes of Ranvier, where it functions in initiation and propagation of action potentials. We examined the role of Nav1.6 in general anesthesia using two mouse mutants with reduced activity of Nav1.6, Scn8amedJ/medJ and Scn8a9J/9J. The mice were exposed to the general anesthetics isoflurane and sevoflurane in step-wise increments; the concentration required to produce loss of righting reflex, a surrogate for anesthetic-induced unconsciousness in rodents, was determined. Mice homozygous for these mutations exhibited increased sensitivity to both isoflurane and sevoflurane. The increased sensitivity was observed during induction of unconsciousness but not during the recovery phase, suggesting that the effect is not attributable to compromised systemic physiology. Electroencephalographic theta power during baseline waking was lower in mutants, suggesting decreased arousal and reduced neuronal excitability. This is the first report linking reduced activity of a specific voltage-gated sodium channel to increased sensitivity to general anesthetics in vivo. PMID:26252017

  15. Initial Evaluation of Active Minds: A Student Organization Dedicated to Reducing the Stigma of Mental Illness

    ERIC Educational Resources Information Center

    McKinney, Kathleen G.

    2009-01-01

    This study examined whether a new student organization, Active Minds, aimed at increasing awareness of "mental illness" and reducing stigma had an impact on students' stigma and willingness to seek psychological help. Three classes were recruited to become involved in the organization. In a pretest/posttest design, stigma and willingness to seek…

  16. Integrated Health and Physical Education Program to Reduce Media Use and Increase Physical Activity in Youth

    ERIC Educational Resources Information Center

    Clocksin, Brian D.; Wattson, Doris L.; Williams, Daniel P.; Randsell, Lynda

    2009-01-01

    The purpose of this project was to compare an integrated health and physical education curriculum, focused on reducing media use and on increasing physical activity in middle school adolescents, to traditional and nonintegrated health and physical education curricula. Two middle schools' health and physical education classes were assigned to an…

  17. Seasonal composition and activity of sulfate-reducing prokaryotic communities in seagrass bed sediments

    EPA Science Inventory

    Sulfate-reducing prokaryotes (SRP) play a key role in the carbon and nutrient cycles of coastal marine, vegetated ecosystems, but the interactions of SRP communities with aquatic plants remain little studied. The abundance, activity, and community composition of SRP was studied i...

  18. The Suppression of Star Formation by Powerful Active Galactic Nuclei

    NASA Technical Reports Server (NTRS)

    Dwek, E.

    2012-01-01

    The old, red stars that constitute the bulges of galaxies, and the massive black holes at their centres, are the relics of a period in cosmic history when galaxies formed stars at remarkable rates and active galactic nuclei (AGN) shone brightly as a result of accretion onto black holes. It is widely suspected, but unproved, that the tight corre1ation between the mass of the black hole and the mas. of the stellar bulge results from the AGN quenching the surrounding star formation as it approaches its peak luminosity. X-rays trace emission from AGN unambiguously, whereas powerful star-forming ga1axies are usually dust-obscured and are brightest at infrared and submillimeter wavelengths. Here we report submillimetre and X-ray observations that show that rapid star formation was common in the host galaxies of AGN when the Universe was 2-6 billion years old, but that the most vigorous star formation is not observed around black holes above an X-ray luminosity of 10(exp 44) ergs per second. This suppression of star formation in the host galaxy of a powerful AGN is a key prediction of models in which the AGN drives an outflow, expe11ing the interstellar medium of its host and transforming the galaxy's properties in a brief period of cosmic time.

  19. The suppression of star formation by powerful active galactic nuclei.

    PubMed

    Page, M J; Symeonidis, M; Vieira, J D; Altieri, B; Amblard, A; Arumugam, V; Aussel, H; Babbedge, T; Blain, A; Bock, J; Boselli, A; Buat, V; Castro-Rodríguez, N; Cava, A; Chanial, P; Clements, D L; Conley, A; Conversi, L; Cooray, A; Dowell, C D; Dubois, E N; Dunlop, J S; Dwek, E; Dye, S; Eales, S; Elbaz, D; Farrah, D; Fox, M; Franceschini, A; Gear, W; Glenn, J; Griffin, M; Halpern, M; Hatziminaoglou, E; Ibar, E; Isaak, K; Ivison, R J; Lagache, G; Levenson, L; Lu, N; Madden, S; Maffei, B; Mainetti, G; Marchetti, L; Nguyen, H T; O'Halloran, B; Oliver, S J; Omont, A; Panuzzo, P; Papageorgiou, A; Pearson, C P; Pérez-Fournon, I; Pohlen, M; Rawlings, J I; Rigopoulou, D; Riguccini, L; Rizzo, D; Rodighiero, G; Roseboom, I G; Rowan-Robinson, M; Sánchez Portal, M; Schulz, B; Scott, D; Seymour, N; Shupe, D L; Smith, A J; Stevens, J A; Trichas, M; Tugwell, K E; Vaccari, M; Valtchanov, I; Viero, M; Vigroux, L; Wang, L; Ward, R; Wright, G; Xu, C K; Zemcov, M

    2012-05-10

    The old, red stars that constitute the bulges of galaxies, and the massive black holes at their centres, are the relics of a period in cosmic history when galaxies formed stars at remarkable rates and active galactic nuclei (AGN) shone brightly as a result of accretion onto black holes. It is widely suspected, but unproved, that the tight correlation between the mass of the black hole and the mass of the stellar bulge results from the AGN quenching the surrounding star formation as it approaches its peak luminosity. X-rays trace emission from AGN unambiguously, whereas powerful star-forming galaxies are usually dust-obscured and are brightest at infrared and submillimetre wavelengths. Here we report submillimetre and X-ray observations that show that rapid star formation was common in the host galaxies of AGN when the Universe was 2-6 billion years old, but that the most vigorous star formation is not observed around black holes above an X-ray luminosity of 10(44) ergs per second. This suppression of star formation in the host galaxy of a powerful AGN is a key prediction of models in which the AGN drives an outflow, expelling the interstellar medium of its host and transforming the galaxy's properties in a brief period of cosmic time. PMID:22575961

  20. Power Factor Study Reduces Energy Costs at Aluminum Extrusion Plant (Alcoa North American Extrusions)

    SciTech Connect

    2001-08-01

    This case study is the latest in a series on industrial firms who are implementing energy efficient technologies and system improvements into their manufacturing processes. The case studies document the activities, savings, and lessons learned on these projects.

  1. Reduced Activity Restriction Buffers the Relations Between Chronic Stress and Sympathetic Nervous System Activation

    PubMed Central

    2014-01-01

    Objectives. Caregivers of dementia patients are at risk for developing cardiovascular disease (CVD), and this risk increases the longer they provide care. Greater perceptions that caregiving restricts social/recreational activities (i.e., activity restriction [AR]) has been associated with poorer health, and AR may exacerbate the relations between stress and health outcomes. The current study examined the interactive role of greater exposure to stress and increased AR on plasma catecholamine (CAT) levels: norepinephrine (NE) and epinephrine (EPI). Method. A total of 84 dementia caregivers completed a standard assessment battery, and a nurse collected blood, which was assayed for NE and EPI. Separate regressions for NE and EPI were used to determine whether the relations between years caregiving and CATs were greater in those with high versus low AR. Results. A significant interaction was found between years caregiving and AR in predicting resting EPI (p = .032) but not resting NE (p = .103). Post hoc analyses indicated that years caregiving was significantly associated with EPI when AR was high (p = .008) but not when AR was low (p = .799). Additionally, years caregiving was not significantly associated with NE when AR was high or low. Discussion. The subjective experience of AR can play an important role in determining risk for detrimental physical health outcomes, particularly CVD risk. PMID:23685924

  2. Activation of aluminum as an effective reducing agent by pitting corrosion for wet-chemical synthesis.

    PubMed

    Li, Wei; Cochell, Thomas; Manthiram, Arumugam

    2013-01-01

    Metallic aluminum (Al) is of interest as a reducing agent because of its low standard reduction potential. However, its surface is invariably covered with a dense aluminum oxide film, which prevents its effective use as a reducing agent in wet-chemical synthesis. Pitting corrosion, known as an undesired reaction destroying Al and is enhanced by anions such as F⁻, Cl⁻, and Br⁻ in aqueous solutions, is applied here for the first time to activate Al as a reducing agent for wet-chemical synthesis of a diverse array of metals and alloys. Specifically, we demonstrate the synthesis of highly dispersed palladium nanoparticles on carbon black with stabilizers and the intermetallic Cu₂Sb/C, which are promising candidates, respectively, for fuel cell catalysts and lithium-ion battery anodes. Atomic hydrogen, an intermediate during the pitting corrosion of Al in protonic solvents (e.g., water and ethylene glycol), is validated as the actual reducing agent. PMID:23390579

  3. Activation of Aluminum as an Effective Reducing Agent by Pitting Corrosion for Wet-chemical Synthesis

    PubMed Central

    Li, Wei; Cochell, Thomas; Manthiram, Arumugam

    2013-01-01

    Metallic aluminum (Al) is of interest as a reducing agent because of its low standard reduction potential. However, its surface is invariably covered with a dense aluminum oxide film, which prevents its effective use as a reducing agent in wet-chemical synthesis. Pitting corrosion, known as an undesired reaction destroying Al and is enhanced by anions such as F−, Cl−, and Br− in aqueous solutions, is applied here for the first time to activate Al as a reducing agent for wet-chemical synthesis of a diverse array of metals and alloys. Specifically, we demonstrate the synthesis of highly dispersed palladium nanoparticles on carbon black with stabilizers and the intermetallic Cu2Sb/C, which are promising candidates, respectively, for fuel cell catalysts and lithium-ion battery anodes. Atomic hydrogen, an intermediate during the pitting corrosion of Al in protonic solvents (e.g., water and ethylene glycol), is validated as the actual reducing agent. PMID:23390579

  4. The Role of Power Doppler Ultrasonography as Disease Activity Marker in Rheumatoid Arthritis

    PubMed Central

    Bhasin, Shaloo; Cheung, Peter P.

    2015-01-01

    Structural damage in rheumatoid arthritis (RA) occurs early if inflammation is not treated promptly. Treatment targeted to reduce inflammation, in particular, that of synovial inflammation in the joints (synovitis), has been recommended as standard treat-to-target recommendations by rheumatologists. The goal is to achieve disease remission (i.e., no disease activity). Several accepted remission criteria have not always equated to the complete absence of true inflammation. Over the last decade, musculoskeletal ultrasonography has been demonstrated to detect subclinical synovitis not appreciated by routine clinical or laboratory assessments, with the Power Doppler modality allowing clinicians to more readily appreciate true inflammation. Thus, targeting therapy to Power Doppler activity may provide superior outcomes compared with treating to clinical targets alone, making it an attractive marker of disease activity in RA. However, more validation on its true benefits such as its benefits to patients in regard to patient related outcomes and issues with standardized training in acquisition and interpretation of power Doppler findings are required. PMID:26063952

  5. Retention of sedentary obese visceral white adipose tissue phenotype with intermittent physical activity despite reduced adiposity.

    PubMed

    Wainright, Katherine S; Fleming, Nicholas J; Rowles, Joe L; Welly, Rebecca J; Zidon, Terese M; Park, Young-Min; Gaines, T'Keaya L; Scroggins, Rebecca J; Anderson-Baucum, Emily K; Hasty, Alyssa H; Vieira-Potter, Victoria J; Padilla, Jaume

    2015-09-01

    Regular physical activity is effective in reducing visceral white adipose tissue (AT) inflammation and oxidative stress, and these changes are commonly associated with reduced adiposity. However, the impact of multiple periods of physical activity, intercalated by periods of inactivity, i.e., intermittent physical activity, on markers of AT inflammation and oxidative stress is unknown. In the present study, 5-wk-old male C57BL/6 mice were randomized into three groups (n = 10/group): sedentary, regular physical activity, and intermittent physical activity, for 24 wk. All animals were singly housed and fed a diet containing 45% kcal from fat. Regularly active mice had access to voluntary running wheels throughout the study period, whereas intermittently active mice had access to running wheels for 3-wk intervals (i.e., 3 wk on/3 wk off) throughout the study. At death, regular and intermittent physical activity was associated with similar reductions in visceral AT mass (approximately -24%, P < 0.05) relative to sedentary. However, regularly, but not intermittently, active mice exhibited decreased expression of visceral AT genes related to inflammation (e.g., monocyte chemoattractant protein 1), immune cell infiltration (e.g., CD68, CD11c, F4/80, CD11b/CD18), oxidative stress (e.g., p47 phagocyte oxidase), and endoplasmic reticulum stress (e.g., CCAAT enhancer-binding protein homologous protein; all P < 0.05). Furthermore, regular, but not intermittent, physical activity was associated with a trend toward improvement in glucose tolerance (P = 0.059). Collectively, these findings suggest that intermittent physical activity over a prolonged period of time may lead to a reduction in adiposity but with retention of a sedentary obese white AT and metabolic phenotype. PMID:26180183

  6. Suppressing Emotions Impairs Subsequent Stroop Performance and Reduces Prefrontal Brain Activation

    PubMed Central

    Luechinger, Roger; Boesiger, Peter; Rasch, Björn

    2013-01-01

    Abundant behavioral evidence suggests that the ability to self-control is limited, and that any exertion of self-control will increase the likelihood of subsequent self-control failures. Here we investigated the neural correlates underlying the aftereffects of self-control on future control processes using functional magnetic resonance imaging (fMRI). An initial act of self-control (suppressing emotions) impaired subsequent performance in a second task requiring control (Stroop task). On the neural level, increased activity during emotion suppression was followed by a relative decrease in activity during the Stroop task in a cluster in the right lateral prefrontal cortex (PFC) including the dorsolateral prefrontal cortex (DLPFC), an area engaged in the effortful implementation of control. There was no reliable evidence for reduced activity in the medial frontal cortex (MFC) including the anterior cingulate cortex (ACC), which is involved in conflict detection processes and has previously also been implicated in self-control. Follow-up analyses showed that the detected cluster in the right lateral PFC and an area in the MFC were involved in both the emotion suppression task and the Stroop task, but only the cluster in the right lateral PFC showed reduced activation after emotion suppression during the Stroop task. Reduced activity in lateral prefrontal areas relevant for the implementation of control may be a critical consequence of prior self-control exertion if the respective areas are involved in both self-control tasks. PMID:23565239

  7. Use of nitroxide spin probes and electron paramagnetic resonance for assessing reducing power of beer. role of SH groups.

    PubMed

    Kocherginsky, Nikolai M; Kostetski, Yuri Yu; Smirnov, Alex I

    2005-02-23

    Intensity of EPR spectra of stable organic free radicals, nitroxides, is decreasing with time if the radicals are dissolved in beer. The process is determined by a chemical reaction of nitroxide reduction by components naturally present in beer. Kinetics can be described as a simple irreversible first order with respect to both nitroxide and one reducing agent. Effective concentration of the reducing agent and the corresponding reaction rate constant has been determined. It is demonstrated that the nitroxide reduction is sensitive to the presence of solvent-accessible SH groups of proteins present in beer. It is proposed that quantitative analysis of reduction kinetics of small water-soluble nitroxide radicals such as TEMPO and TEMPOL can be used to assess the reducing power of beer. The effect of accelerated aging of beer achieved at elevated temperatures on nitroxide reduction kinetics is demonstrated. PMID:15713019

  8. Reducible poly(2-dimethylaminoethyl methacrylate): synthesis, cytotoxicity, and gene delivery activity.

    PubMed

    You, Ye-Zi; Manickam, Devika Soundara; Zhou, Qing-Hui; Oupický, David

    2007-10-01

    Reducible polycations represent promising carriers of therapeutic nucleic acids. Oligomers of 2-dimethylaminoethyl methacrylate (DMAEMA) containing terminal thiol groups were synthesized by reversible addition-fragmentation chain transfer (RAFT) polymerization using difunctional chain transfer agent. Reducible poly(DMAEMA) (rPDMAEMA) was synthesized by oxidation of the terminal thiol groups, forming a polymer with disulfide bonds in the backbone. Physico-chemical properties of DNA polyplexes of rPDMAEMA were evaluated by dynamic and static light scattering methods, revealing lower structural density and DNA content than control PDMAEMA polyplexes. Cytotoxicity and transfection activity of rPDMAEMA-based DNA polyplexes were evaluated in vitro. In comparison with control PDMAEMA, only minimum toxic effects of rPDMAEMA were observed in a panel of cell lines. Transfection activity was tested in B16F10 mouse melanoma and six human pancreatic cancer cell lines. rPDMAEMA polyplexes showed a comparable or better activity than control PDMAEMA polyplexes. PMID:17574292

  9. Reducible poly(2-dimethylaminoethyl methacrylate): Synthesis, cytotoxicity, and gene delivery activity

    PubMed Central

    Zhou, Qing-Hui; Oupický, David

    2007-01-01

    Reducible polycations represent promising carriers of therapeutic nucleic acids. Oligomers of 2-dimethylaminoethyl methacrylate (DMAEMA) containing terminal thiol groups were synthesized by reversible addition-fragmentation chain transfer (RAFT) polymerization using difunctional chain transfer agent. Reducible poly(DMAEMA) (rPDMAEMA) was synthesized by oxidation of the terminal thiol groups, forming a polymer with disulfide bonds in the backbone. Physico-chemical properties of DNA polyplexes of rPDMAEMA were evaluated by dynamic and light scattering methods, revealing lower structural density and DNA content than control PDMAEMA polyplexes. Cytotoxicity and transfection activity of rPDMAEMA-based DNA polyplexes were evaluated in vitro. In comparison with control PDMAEMA, only minimum toxic effects of rPDMAEMA were observed in a panel of cell lines. Transfection activity was tested in B16F10 mouse melanoma and six human pancreatic cancer cell lines. rPDMAEMA polyplexes showed a comparable or better activity than control PDMAEMA polyplexes. PMID:17574292

  10. Reduced hippocampal and amygdala activity predicts memory distortions for trauma reminders in combat-related PTSD.

    PubMed

    Hayes, Jasmeet Pannu; LaBar, Kevin S; McCarthy, Gregory; Selgrade, Elizabeth; Nasser, Jessica; Dolcos, Florin; Morey, Rajendra A

    2011-05-01

    Neurobiological models of posttraumatic stress disorder (PTSD) suggest that altered activity in the medial temporal lobes (MTL) during encoding of traumatic memories contribute to the development and maintenance of the disorder. However, there is little direct evidence in the PTSD literature to support these models. The goal of the present study was to examine MTL activity during trauma encoding in combat veterans using the subsequent memory paradigm. Fifteen combat veterans diagnosed with PTSD and 14 trauma-exposed control participants viewed trauma-related and neutral pictures while undergoing event-related fMRI. Participants returned one week after scanning for a recognition memory test. Region-of-interest (ROI) and voxel-wise whole brain analyses were conducted to examine the neural correlates of successful memory encoding. Patients with PTSD showed greater false alarm rates for novel lures than the trauma-exposed control group, suggesting reliance on gist-based representations in lieu of encoding contextual details. Imaging analyses revealed reduced activity in the amygdala and hippocampus in PTSD patients during successful encoding of trauma-related stimuli. Reduction in left hippocampal activity was associated with high arousal symptoms on the Clinician-Administered PTSD Scale (CAPS). The behavioral false alarm rate for traumatic stimuli co-varied with activity in the bilateral precuneus. These results support neurobiological theories positing reduced hippocampal activity under conditions of high stress and arousal. Reduction in MTL activity for successfully encoded stimuli and increased precuneus activity may underlie reduced stimulus-specific encoding and greater gist memory in patients with PTSD, leading to maintenance of the disorder. PMID:21047644

  11. Reduced Denitration Activity in Peripheral Lung of Chronic Obstructive Pulmonary Disease

    PubMed Central

    Osoata, Grace O.; Ito, Misako; Elliot, Mark; Hogg, James; Barnes, Peter J.

    2012-01-01

    Background Accumulation of nitrated protein is seen in peripheral lung and cells from patients with chronic obstructive pulmonary disease (COPD). Nitrated protein causes abnormal protein function, but the nitration was believed to be an irreversible process. However, there are accumulating evidences that this process is reversible by an active denitration pathway. The aim of this study is to detect denitration activity in protein extracts from peripheral lung tissue of COPD and to compare with those in healthy subjects. Materials and Methods Peripheral lung tissue from 4 healthy, 4 smokers without COPD, 4 GOLD stage 1 and 4 GOLD stage 2 were used for denitration assay. Denitration activity was determined as reduction of nitro-tyrosine level of nitrated histone protein after incubation with protein extracts from peripheral lung, which was determined by western blotting. In addition, RNA is extracted from peripheral lung of 8 healthy, 7 smoking control, 8 stage 1 and 2 COPD and 10 stage 3 and 4 COPD and nitrate reductase mRNA expression was determined by real time RT-PCR. Results Peripheral lung protein extracts from healthy subjects reduced nitro-tyrosine level of nitrated histone. Thus, we were able to show denitration activity in peripheral lungs. The denitration activity was slightly reduced in smoking controls, and significantly reduced in COPD patients. We also showed that the expression of the human homologue of nitrate reductase (chytochrome β2 reductase), a potential candidate of denitrase, was significanty reduced in COPD lung. Conclusion This study suggests that accumulation of nitrated protein in lung tissue of COPD may, at least in part, be induced by a reduction in denitration activity or nitrate reductase. PMID:25191434

  12. Nandrolone reduces activation of Notch signaling in denervated muscle associated with increased Numb expression.

    PubMed

    Liu, Xin-Hua; Yao, Shen; Qiao, Rui-Fang; Levine, Alice C; Kirschenbaum, Alexander; Pan, Jiangping; Wu, Yong; Qin, Weiping; Bauman, William A; Cardozo, Christopher P

    2011-10-14

    Nandrolone, an anabolic steroid, slows denervation-atrophy in rat muscle. The molecular mechanisms responsible for this effect are not well understood. Androgens and anabolic steroids activate Notch signaling in animal models of aging and thereby mitigate sarcopenia. To explore the molecular mechanisms by which nandrolone prevents denervation-atrophy, we investigated the effects of nandrolone on Notch signaling in denervated rat gastrocnemius muscle. Denervation significantly increased Notch activity reflected by elevated levels of nuclear Notch intracellular domain (NICD) and expression of Hey1 (a Notch target gene). Activation was greatest at 7 and 35 days after denervation but remained present at 56 days after denervation. Activation of Notch in denervated muscle was prevented by nandrolone associated with upregulated expression of Numb mRNA and protein. These data demonstrate that denervation activates Notch signaling, and that nandrolone abrogates this response associated with increased expression of Numb, suggesting a potential mechanism by which nandrolone reduces denervation-atrophy. PMID:21945932

  13. Thermally Reduced Graphene Oxide Electrochemically Activated by Bis-Spiro Quaternary Alkyl Ammonium for Capacitors.

    PubMed

    He, Tieshi; Meng, Xiangling; Nie, Junping; Tong, Yujin; Cai, Kedi

    2016-06-01

    Thermally reduced graphene oxide (RGO) electrochemically activated by a quaternary alkyl ammonium-based organic electrolytes/activated carbon (AC) electrode asymmetric capacitor is proposed. The electrochemical activation process includes adsorption of anions into the pores of AC in the positive electrode and the interlayer intercalation of cations into RGO in the negative electrode under high potential (4.0 V). The EA process of RGO by quaternary alkyl ammonium was investigated by X-ray diffraction and electrochemical measurements, and the effects of cation size and structure were extensively evaluated. Intercalation by quaternary alkyl ammonium demonstrates a small degree of expansion of the whole crystal lattice (d002) and a large degree of expansion of the partial crystal lattice (d002) of RGO. RGO electrochemically activated by bis-spiro quaternary alkyl ammonium in propylene carbonate/AC asymmetric capacitor exhibits good activated efficiency, high specific capacity, and stable cyclability. PMID:27180820

  14. Interleukin-1β biosynthesis inhibition reduces acute seizures and drug resistant chronic epileptic activity in mice.

    PubMed

    Maroso, Mattia; Balosso, Silvia; Ravizza, Teresa; Iori, Valentina; Wright, Christopher Ian; French, Jacqueline; Vezzani, Annamaria

    2011-04-01

    Experimental evidence and clinical observations indicate that brain inflammation is an important factor in epilepsy. In particular, induction of interleukin-converting enzyme (ICE)/caspase-1 and activation of interleukin (IL)-1β/IL-1 receptor type 1 axis both occur in human epilepsy, and contribute to experimentally induced acute seizures. In this study, the anticonvulsant activity of VX-765 (a selective ICE/caspase-1 inhibitor) was examined in a mouse model of chronic epilepsy with spontaneous recurrent epileptic activity refractory to some common anticonvulsant drugs. Moreover, the effects of this drug were studied in one acute model of seizures in mice, previously shown to involve activation of ICE/caspase-1. Quantitative analysis of electroencephalogram activity was done in mice exposed to acute seizures or those developing chronic epileptic activity after status epilepticus to assess the anticonvulsant effects of systemic administration of VX-765. Histological and immunohistochemical analysis of brain tissue was carried out at the end of pharmacological experiments in epileptic mice to evaluate neuropathology, glia activation and IL-1β expression, and the effect of treatment. Repeated systemic administration of VX-765 significantly reduced chronic epileptic activity in mice in a dose-dependent fashion (12.5-200 mg/kg). This effect was observed at doses ≥ 50 mg/kg, and was reversible with discontinuation of the drug. Maximal drug effect was associated with inhibition of IL-1β synthesis in activated astrocytes. The same dose regimen of VX-765 also reduced acute seizures in mice and delayed their onset time. These results support a new target system for anticonvulsant pharmacological intervention to control epileptic activity that does not respond to some common anticonvulsant drugs. PMID:21431948

  15. Neural correlates of reduced awareness in instrumental activities of daily living in frontotemporal dementia.

    PubMed

    Amanzio, Martina; D'Agata, Federico; Palermo, Sara; Rubino, Elisa; Zucca, Milena; Galati, Antonello; Pinessi, Lorenzo; Castellano, Giancarlo; Rainero, Innocenzo

    2016-10-01

    A decline in instrumental activities of daily living has been described as the earliest functional deficit in patients with neurodegenerative disease. It embraces specific competencies such as: "recalling the date and telephone calls, orienting to new places, remembering the location of objects at home, understanding conversation and the plot of a movie, keeping belongings in order, doing mental calculations and handling money, remembering appointments and shopping lists and performing clerical work". Since changes in instrumental daily living activities are one of the descriptors of behavioural-variant frontotemporal dementia, we decided to investigate the neural correlates of a reduced awareness in this specific domain in twenty-three consecutive behavioural-variant frontotemporal dementia patients. Gray matter volume changes associated with a reduced awareness for the instrumental domain, assessed using a validated caregiver-patient discrepancy questionnaire, were examined. Interestingly, we found disabilities in instrumental daily living activities and a reduced awareness of these to be related to medial prefrontal cortex atrophy, where the mid-cingulate cortices, dorsal anterior insula and cuneous play an important role. Importantly, if the executive system does not function correctly, the comparator mechanism of action self-monitoring does not detect mismatches between the current and previous performance states stored in the personal database, and produces a reduced awareness for the instrumental domain. PMID:27534380

  16. Buprenorphine Reduces Alcohol Drinking Through Activation of the Nociceptin/Orphanin FQ-NOP Receptor System

    PubMed Central

    Ciccocioppo, Roberto; Economidou, Daina; Rimondini, Roberto; Sommer, Wolfgang; Massi, Maurizio; Heilig, Markus

    2011-01-01

    Background Activation of the NOP receptor by its endogenous ligand nociceptin/orphanin FQ reduces ethanol intake in genetically selected alcohol preferring Marchigian Sardinian alcohol preferring (msP) rats. Here we evaluated whether buprenorphine, a partial agonist at μ-opioid and NOP receptors, would reduce ethanol consumption in msP rats via activation of NOP receptors. Methods Marchigian Sardinian alcohol preferring rats trained to drink 10% alcohol 2 hours/day were injected with buprenorphine (.03, .3, 3.0, or 6.0 mg/kg intraperitoneally [IP]) 90 min before access to ethanol. Results Similar to prototypical μ-agonists, the two lowest doses of buprenorphine significantly increased ethanol consumption (p < .01); in contrast, the two highest doses reduced it (p < .05). Pretreatment with naltrexone (.25 mg/kg IP) prevented the increase of ethanol intake induced by .03 mg/kg of buprenorphine (p < .001) but did not affect the inhibition of ethanol drinking induced by 3.0 mg/kg of buprenorphine. Conversely, pretreatment with the selective NOP receptor antagonist UFP-101 (10.0 or 20.0 μg/rat) abolished the suppression of ethanol drinking by 3.0 mg/kg of buprenorphine. Conclusions Buprenorphine has dualistic effects on ethanol drinking; low doses increase alcohol intake via stimulation of classic opioid receptors, whereas higher doses reduce it via activation of NOP receptors. We suggest that NOP agonistic properties of buprenorphine might be useful in the treatment of alcoholism. PMID:16533497

  17. Methods of reducing energy consumption of the oxidant supply system for MHD/steam power plants

    NASA Technical Reports Server (NTRS)

    Juhasz, A. J.

    1983-01-01

    An in-depth study was conducted to identify possible improvements to the oxidant supply system for combined cycle MHD power plants which would lead to higher thermal efficiency and reduction in the cost of electricity, COE. Results showed that the oxidant system energy consumption could be minimized when the process was designed to deliver a product O2 concentration of 70 mole percent. The study also led to the development of a new air separation process, referred to as liquid pumping and internal compression. MHD system performance calculations show that the new process would permit an increase in plant thermal efficiency of 0.6 percent while allowing more favorable tradeoffs between magnetic energy and oxidant system capacity requirements.

  18. Methods of reducing energy consumption of the oxidant supply system for MHD/steam power plants

    NASA Technical Reports Server (NTRS)

    Juhasz, A. J.

    1983-01-01

    An in-depth study was conducted to identify possible improvements to the oxidant supply system for combined cycle MHD power plants which would lead to higher thermal efficiency and reduction in the cost of electricity, COE. Results showed that the oxidant system energy consumption could be minimized when the process was designed to deliver a product O2 concentration of 70 mole percent. The study also led to the development of a new air separation process, referred to as 'liquid pumping and internal compression'. MHD system performance calculations show that the new process would permit an increase in plant thermal efficiency of 0.6 percent while allowing more favorable tradeoffs between magnetic energy and oxidant system capacity requirements.

  19. Green synthesis of biphasic TiO₂-reduced graphene oxide nanocomposites with highly enhanced photocatalytic activity.

    PubMed

    Sher Shah, Md Selim Arif; Park, A Reum; Zhang, Kan; Park, Jong Hyeok; Yoo, Pil J

    2012-08-01

    A series of TiO(2)-reduced graphene oxide (RGO) nanocomposites were prepared by simple one-step hydrothermal reactions using the titania precursor, TiCl(4) and graphene oxide (GO) without reducing agents. Hydrolysis of TiCl(4) and mild reduction of GO were simultaneously carried out under hydrothermal conditions. While conventional approaches mostly utilize multistep chemical methods wherein strong reducing agents, such as hydrazine, hydroquinone, and sodium borohydride are employed, our method provides the notable advantages of a single step reaction without employing toxic solvents or reducing agents, thereby providing a novel green synthetic route to produce the nanocomposites of RGO and TiO(2). The as-synthesized nanocomposites were characterized by several crystallographic, microscopic, and spectroscopic characterization methods, which enabled confrimation of the robustness of the suggested reaction scheme. Notably, X-ray diffraction and transmission electron micrograph proved that TiO(2) contained both anatase and rutile phases. In addition, the photocatalytic activities of the synthesized composites were measured for the degradation of rhodamine B dye. The catalyst also can degrade a colorless dye such as benzoic acid under visible light. The synthesized nanocomposites of biphasic TiO(2) with RGO showed enhanced catalytic activity compared to conventional TiO(2) photocatalyst, P25. The photocatalytic activity is strongly affected by the concentration of RGO in the nanocomposites, with the best photocatalytic activity observed for the composite of 2.0 wt % RGO. Since the synthesized biphasic TiO(2)-RGO nanocomposites have been shown to effectively reduce the electron-hole recombination rate, it is anticipated that they will be utilized as anode materials in lithium ion batteries. PMID:22788800

  20. Enhanced Somatosensory Feedback Reduces Prefrontal Cortical Activity During Walking in Older Adults

    PubMed Central

    Christou, Evangelos A.; Ring, Sarah A.; Williamson, John B.; Doty, Leilani

    2014-01-01

    Background. The coordination of steady state walking is relatively automatic in healthy humans, such that active attention to the details of task execution and performance (controlled processing) is low. Somatosensation is a crucial input to the spinal and brainstem circuits that facilitate this automaticity. Impaired somatosensation in older adults may reduce automaticity and increase controlled processing, thereby contributing to deficits in walking function. The primary objective of this study was to determine if enhancing somatosensory feedback can reduce controlled processing during walking, as assessed by prefrontal cortical activation. Methods. Fourteen older adults (age 77.1±5.56 years) with mild mobility deficits and mild somatosensory deficits participated in this study. Functional near-infrared spectroscopy was used to quantify metabolic activity (tissue oxygenation index, TOI) in the prefrontal cortex. Prefrontal activity and gait spatiotemporal data were measured during treadmill walking and overground walking while participants wore normal shoes and under two conditions of enhanced somatosensation: wearing textured insoles and no shoes. Results. Relative to walking with normal shoes, textured insoles yielded a bilateral reduction of prefrontal cortical activity for treadmill walking (ΔTOI = −0.85 and −1.19 for left and right hemispheres, respectively) and for overground walking (ΔTOI = −0.51 and −0.66 for left and right hemispheres, respectively). Relative to walking with normal shoes, no shoes yielded lower prefrontal cortical activity for treadmill walking (ΔTOI = −0.69 and −1.13 for left and right hemispheres, respectively), but not overground walking. Conclusions. Enhanced somatosensation reduces prefrontal activity during walking in older adults. This suggests a less intensive utilization of controlled processing during walking. PMID:25112494

  1. Eculizumab reduces complement activation, inflammation, endothelial damage, thrombosis, and renal injury markers in aHUS

    PubMed Central

    Cofiell, Roxanne; Kukreja, Anjli; Bedard, Krystin; Yan, Yan; Mickle, Angela P.; Ogawa, Masayo; Bedrosian, Camille L.

    2015-01-01

    Atypical hemolytic uremic syndrome (aHUS) is a genetic, life-threatening disease characterized by uncontrolled complement activation, systemic thrombotic microangiopathy (TMA), and vital organ damage. We evaluated the effect of terminal complement blockade with the anti-C5 monoclonal antibody eculizumab on biomarkers of cellular processes involved in TMA in patients with aHUS longitudinally, during up to 1 year of treatment, compared with in healthy volunteers. Biomarker levels were elevated at baseline in most patients, regardless of mutational status, plasma exchange/infusion use, platelet count, or lactate dehydrogenase or haptoglobin levels. Eculizumab reduced terminal complement activation (C5a and sC5b-9) and renal injury markers (clusterin, cystatin-C, β2-microglobulin, and liver fatty acid binding protein-1) to healthy volunteer levels and reduced inflammation (soluble tumor necrosis factor receptor-1), coagulation (prothrombin fragment F1+2 and d-dimer), and endothelial damage (thrombomodulin) markers to near-normal levels. Alternative pathway activation (Ba) and endothelial activation markers (soluble vascular cell adhesion molecule-1) decreased but remained elevated, reflecting ongoing complement activation in aHUS despite complete terminal complement blockade. These results highlight links between terminal complement activation and inflammation, endothelial damage, thrombosis, and renal injury and underscore ongoing risk for systemic TMA and progression to organ damage. Further research regarding underlying complement dysregulation is warranted. This trial was registered at www.clinicaltrials.gov as #NCT01194973. PMID:25833956

  2. Toll-Like Receptor 4 Reduces Oxidative Injury via Glutathione Activity in Sheep.

    PubMed

    Deng, Shoulong; Yu, Kun; Wu, Qian; Li, Yan; Zhang, Xiaosheng; Zhang, Baolu; Liu, Guoshi; Liu, Yixun; Lian, Zhengxing

    2016-01-01

    Toll-like receptor 4 (TLR4) is an important sensor of Gram-negative bacteria and can trigger activation of the innate immune system. Increased activation of TLR4 can lead to the induction of oxidative stress. Herein, the pathway whereby TLR4 affects antioxidant activity was studied. In TLR4-overexpressing sheep, TLR4 expression was found to be related to the integration copy number when monocytes were challenged with lipopolysaccharide (LPS). Consequently, production of malondialdehyde (MDA) was increased, which could increase the activation of prooxidative stress enzymes. Meanwhile, activation of an antioxidative enzyme, glutathione peroxidase (GSH-Px), was increased. Real-time PCR showed that expression of activating protein-1 (AP-1) and the antioxidative-related genes was increased. By contrast, the expression levels of superoxide dismutase 1 (SOD1) and catalase (CAT) were reduced. In transgenic sheep, glutathione (GSH) levels were dramatically reduced. Furthermore, transgenic sheep were intradermally injected with LPS in each ear. The amounts of inflammatory infiltrates were correlated with the number of TLR4 copies that were integrated in the genome. Additionally, the translation of γ-glutamylcysteine synthetase (γ-GCS) was increased. Our findings indicated that overexpression of TLR4 in sheep could ameliorate oxidative injury through GSH secretion that was induced by LPS stimulation. Furthermore, TLR4 promoted γ-GCS translation through the AP-1 pathway, which was essential for GSH synthesis. PMID:26640618

  3. Toll-Like Receptor 4 Reduces Oxidative Injury via Glutathione Activity in Sheep

    PubMed Central

    Deng, Shoulong; Yu, Kun; Wu, Qian; Li, Yan; Zhang, Xiaosheng; Zhang, Baolu; Liu, Guoshi; Liu, Yixun; Lian, Zhengxing

    2016-01-01

    Toll-like receptor 4 (TLR4) is an important sensor of Gram-negative bacteria and can trigger activation of the innate immune system. Increased activation of TLR4 can lead to the induction of oxidative stress. Herein, the pathway whereby TLR4 affects antioxidant activity was studied. In TLR4-overexpressing sheep, TLR4 expression was found to be related to the integration copy number when monocytes were challenged with lipopolysaccharide (LPS). Consequently, production of malondialdehyde (MDA) was increased, which could increase the activation of prooxidative stress enzymes. Meanwhile, activation of an antioxidative enzyme, glutathione peroxidase (GSH-Px), was increased. Real-time PCR showed that expression of activating protein-1 (AP-1) and the antioxidative-related genes was increased. By contrast, the expression levels of superoxide dismutase 1 (SOD1) and catalase (CAT) were reduced. In transgenic sheep, glutathione (GSH) levels were dramatically reduced. Furthermore, transgenic sheep were intradermally injected with LPS in each ear. The amounts of inflammatory infiltrates were correlated with the number of TLR4 copies that were integrated in the genome. Additionally, the translation of γ-glutamylcysteine synthetase (γ-GCS) was increased. Our findings indicated that overexpression of TLR4 in sheep could ameliorate oxidative injury through GSH secretion that was induced by LPS stimulation. Furthermore, TLR4 promoted γ-GCS translation through the AP-1 pathway, which was essential for GSH synthesis. PMID:26640618

  4. Heat-treatment effect on impact properties of reduced-activation steels*1

    NASA Astrophysics Data System (ADS)

    Klueh, R. L.; Maziasz, P. J.; Alexander, D. J.

    1991-03-01

    The effect of heat treatment on the impact behavior of eight experimental heats of reduced-activation ferritic steels was investigated. Steels with 2 {1}/{4}, 5, 9, and 12 wt% Cr and containing tungsten, vanadium, and tantalum were examined. Impact properties of steels with 2 {1}/{4} wt% Cr depended on microstructure, which was affected by cooling rate after austenitization. By heat-treating the 2 {1}/{4} wt% Cr steels to change the microstructure from a bainitic structure containing ferrite to one without ferrite, the ductile-brittle transition temperatures were reduced substantially. The cooling rate had essentially no effect on the high-chromium martensitic steels.

  5. Resistive switching behavior of reduced graphene oxide memory cells for low power nonvolatile device application

    PubMed Central

    Pradhan, Sangram K.; Xiao, Bo; Mishra, Saswat; Killam, Alex; Pradhan, Aswini K.

    2016-01-01

    Graphene Oxide (GO) based low cost flexible electronics and memory cell have recently attracted more attention for the fabrication of emerging electronic devices. As a suitable candidate for resistive random access memory technology, reduced graphene oxide (RGO) can be widely used for non-volatile switching memory applications because of its large surface area, excellent scalability, retention, and endurance properties. We demonstrated that the fabricated metal/RGO/metal memory device exhibited excellent switching characteristics, with on/off ratio of two orders of magnitude and operated threshold switching voltage of less than 1 V. The studies on different cell diameter, thickness, scan voltages and period of time corroborate the reliability of the device as resistive random access memory. The microscopic origin of switching operation is governed by the establishment of conducting filaments due to the interface amorphous layer rupturing and the movement of oxygen in the GO layer. This interesting experimental finding indicates that device made up of thermally reduced GO shows more reliability for its use in next generation electronics devices. PMID:27240537

  6. The power to reduce: pyridine nucleotides--small molecules with a multitude of functions.

    PubMed

    Pollak, Nadine; Dölle, Christian; Ziegler, Mathias

    2007-03-01

    The pyridine nucleotides NAD and NADP play vital roles in metabolic conversions as signal transducers and in cellular defence systems. Both coenzymes participate as electron carriers in energy transduction and biosynthetic processes. Their oxidized forms, NAD+ and NADP+, have been identified as important elements of regulatory pathways. In particular, NAD+ serves as a substrate for ADP-ribosylation reactions and for the Sir2 family of NAD+-dependent protein deacetylases as well as a precursor of the calcium mobilizing molecule cADPr (cyclic ADP-ribose). The conversions of NADP+ into the 2'-phosphorylated form of cADPr or to its nicotinic acid derivative, NAADP, also result in the formation of potent intracellular calcium-signalling agents. Perhaps, the most critical function of NADP is in the maintenance of a pool of reducing equivalents which is essential to counteract oxidative damage and for other detoxifying reactions. It is well known that the NADPH/NADP+ ratio is usually kept high, in favour of the reduced form. Research within the past few years has revealed important insights into how the NADPH pool is generated and maintained in different subcellular compartments. Moreover, tremendous progress in the molecular characterization of NAD kinases has established these enzymes as vital factors for cell survival. In the present review, we summarize recent advances in the understanding of the biosynthesis and signalling functions of NAD(P) and highlight the new insights into the molecular mechanisms of NADPH generation and their roles in cell physiology. PMID:17295611

  7. Resistive switching behavior of reduced graphene oxide memory cells for low power nonvolatile device application

    NASA Astrophysics Data System (ADS)

    Pradhan, Sangram K.; Xiao, Bo; Mishra, Saswat; Killam, Alex; Pradhan, Aswini K.

    2016-05-01

    Graphene Oxide (GO) based low cost flexible electronics and memory cell have recently attracted more attention for the fabrication of emerging electronic devices. As a suitable candidate for resistive random access memory technology, reduced graphene oxide (RGO) can be widely used for non-volatile switching memory applications because of its large surface area, excellent scalability, retention, and endurance properties. We demonstrated that the fabricated metal/RGO/metal memory device exhibited excellent switching characteristics, with on/off ratio of two orders of magnitude and operated threshold switching voltage of less than 1 V. The studies on different cell diameter, thickness, scan voltages and period of time corroborate the reliability of the device as resistive random access memory. The microscopic origin of switching operation is governed by the establishment of conducting filaments due to the interface amorphous layer rupturing and the movement of oxygen in the GO layer. This interesting experimental finding indicates that device made up of thermally reduced GO shows more reliability for its use in next generation electronics devices.

  8. Resistive switching behavior of reduced graphene oxide memory cells for low power nonvolatile device application.

    PubMed

    Pradhan, Sangram K; Xiao, Bo; Mishra, Saswat; Killam, Alex; Pradhan, Aswini K

    2016-01-01

    Graphene Oxide (GO) based low cost flexible electronics and memory cell have recently attracted more attention for the fabrication of emerging electronic devices. As a suitable candidate for resistive random access memory technology, reduced graphene oxide (RGO) can be widely used for non-volatile switching memory applications because of its large surface area, excellent scalability, retention, and endurance properties. We demonstrated that the fabricated metal/RGO/metal memory device exhibited excellent switching characteristics, with on/off ratio of two orders of magnitude and operated threshold switching voltage of less than 1 V. The studies on different cell diameter, thickness, scan voltages and period of time corroborate the reliability of the device as resistive random access memory. The microscopic origin of switching operation is governed by the establishment of conducting filaments due to the interface amorphous layer rupturing and the movement of oxygen in the GO layer. This interesting experimental finding indicates that device made up of thermally reduced GO shows more reliability for its use in next generation electronics devices. PMID:27240537

  9. Pertussis toxin analog with reduced enzymatic and biological activities is a protective immunogen.

    PubMed Central

    Kimura, A; Mountzouros, K T; Schad, P A; Cieplak, W; Cowell, J L

    1990-01-01

    Bordetella pertussis TOX3201 has a 12-base-pair insertion in the S1 subunit gene of pertussis toxin (PTX), which encodes for a 4-amino-acid insertion between residues 107 and 108 of the mature S1 subunit (Black et al., Science 240:656-659, 1988). This mutant strain has been shown to secrete a holotoxin analog of PTX, designated CRM3201, with reduced ADP-ribosyltransferase activity. In the present study, we evaluated the biochemical, biological, and immunoprotective activities of purified CRM3201. Assay of enzymatic activities showed that CRM3201 had 20 to 30% of the ADP-ribosyltransferase activity and 55 to 60% of the NAD glycohydrolase activity of native PTX. CRM3201, however, had only 2 to 6% of the activity of PTX in clustering CHO cells, promoting leukocytosis, inducing histamine sensitization, and potentiating an anaphylactic response to bovine serum albumin. In contrast, activities associated with the B oligomer (binding to fetuin, hemagglutination of goose erythrocytes, and lymphocyte mitogen activity) were comparable to those of native PTX. Injection of BALB/c mice with CRM3201 mixed with Al(OH)3 elicited high titers of antibody to PTX (as measured by enzyme-linked immunosorbent assay), which neutralized a leukocytosis-promoting dose of PTX in these mice and neutralized PTX in a CHO cell assay. Passive transfer of the anti-CRM3201 antibody protected 20-day-old Swiss-Webster mice against a lethal aerosol challenge with B. pertussis 18323. Active immunization with CRM3201 significantly reduced lung colonization in adult BALB/c mice with a B. pertussis respiratory infection. These results demonstrate (i) that the reduced ADP-ribosyltransferase activity of CRM3201 is associated with reductions in certain biological and toxic activities of PTX (the enzymatic and biological activities are not, however, totally concordant); (ii) that CRM3201 possesses a functional B oligomer; and (iii) that CRM3201 can induce toxin-neutralizing antibodies which protect mice

  10. AMP-activated Protein Kinase Suppresses Biosynthesis of Glucosylceramide by Reducing Intracellular Sugar Nucleotides*

    PubMed Central

    Ishibashi, Yohei; Hirabayashi, Yoshio

    2015-01-01

    The membrane glycolipid glucosylceramide (GlcCer) plays a critical role in cellular homeostasis. Its intracellular levels are thought to be tightly regulated. How cells regulate GlcCer levels remains to be clarified. AMP-activated protein kinase (AMPK), which is a crucial cellular energy sensor, regulates glucose and lipid metabolism to maintain energy homeostasis. Here, we investigated whether AMPK affects GlcCer metabolism. AMPK activators (5-aminoimidazole-4-carboxamide 1-β-d-ribofuranoside and metformin) decreased intracellular GlcCer levels and synthase activity in mouse fibroblasts. AMPK inhibitors or AMPK siRNA reversed these effects, suggesting that GlcCer synthesis is negatively regulated by an AMPK-dependent mechanism. Although AMPK did not affect the phosphorylation or expression of GlcCer synthase, the amount of UDP-glucose, an activated form of glucose required for GlcCer synthesis, decreased under AMPK-activating conditions. Importantly, the UDP-glucose pyrophosphatase Nudt14, which degrades UDP-glucose, generating UMP and glucose 1-phosphate, was phosphorylated and activated by AMPK. On the other hand, suppression of Nudt14 by siRNA had little effect on UDP-glucose levels, indicating that mammalian cells have an alternative UDP-glucose pyrophosphatase that mainly contributes to the reduction of UDP-glucose under AMPK-activating conditions. Because AMPK activators are capable of reducing GlcCer levels in cells from Gaucher disease patients, our findings suggest that reducing GlcCer through AMPK activation may lead to a new strategy for treating diseases caused by abnormal accumulation of GlcCer. PMID:26048992

  11. Lysosomal Acid Lipase Activity Is Reduced Both in Cryptogenic Cirrhosis and in Cirrhosis of Known Etiology

    PubMed Central

    Vespasiani-Gentilucci, Umberto; Gallo, Paolo; Piemonte, Fiorella; Riva, Elisabetta; Porcari, Aldostefano; Vorini, Ferruccio; Tozzi, Giulia; Piccioni, Livia; Galati, Giovanni; De Vincentis, Antonio; Carotti, Simone; Morini, Sergio; D’Amico, Jessica; Angeletti, Silvia; Pedone, Claudio; Picardi, Antonio

    2016-01-01

    Lysosomal acid lipase deficiency (LAL-d) is a rare autosomal recessive disease in which LAL activity is almost absent, with consequent massive microvesicular steatosis evolving to cirrhosis and liver failure. We aimed to determine LAL-activity, and to investigate the most common single nucleotide polymorphism (SNP) affecting the LIPA gene and responsible for 50–70% of LAL-d cases (rs116928232 c.894G>A), in patients with cryptogenic cirrhosis. Sixty-three patients with cryptogenic cirrhosis, 88 cirrhotics of known etiology, and 97 healthy subjects were enrolled. LAL-activity was determined in dried-blood-spot (DBS). The c.894G>A mutation was analyzed by pyrosequencing method in SNP mode. LAL-activity was severely reduced in patients with cryptogenic cirrhosis with respect to healthy subjects [0.62 (0.44–0.86) Vs 0.96 (0.75–1.25) nmol/spot/h, p<0.001)], but it was also reduced in known-etiology cirrhotics [0.54 (0.42–0.79) nmol/spot/h, p<0.001 Vs healthy subjects; p = 0.5 Vs cryptogenic cirrhotics]. Fourteen percent of cryptogenic cirrhotics and 20% of known-etiology cirrhotics showed a LAL-activity in the range of heterozygous carriers of LIPA gene mutations (0.15–0.40 nmol/spot/h). However, none of the subjects with reduced LAL-activity carried the c.894G>A SNP except for one patient with HCV cirrhosis. By multivariate analysis, LAL-activity was not associated with age, sex, liver enzymes, liver function or lipid parameters, while it was independently associated with white blood cell (β = 0.2; p<0.01) and platelet (β = 0.4; p<0.001) counts and with the condition of cirrhosis (β = -0.2; p = 0.04). Conclusion Liver cirrhosis is characterized by a severe acquired reduction of LAL-activity, the precise causes and consequences of which need to be further addressed. DBS-determined lysosomal enzyme activities seem to be affected by white blood cell and platelet counts, and the specificity of these tests can be reduced when applied to determined populations

  12. The power of positive thinking: Pathological worry is reduced by thought replacement in Generalized Anxiety Disorder

    PubMed Central

    Eagleson, Claire; Hayes, Sarra; Mathews, Andrew; Perman, Gemma; Hirsch, Colette R.

    2016-01-01

    Worry in Generalized Anxiety Disorder (GAD), takes a predominantly verbal form, as if talking to oneself about possible negative outcomes. The current study examined alternative approaches to reducing worry by allocating volunteers with GAD to conditions in which they either practiced replacing the usual form of worry with images of possible positive outcomes, or with the same positive outcomes represented verbally. A comparison control condition involved generating positive images not related to worries. Participants received training in the designated method and then practiced it for one week, before attending for reassessment, and completing follow-up questionnaires four weeks later. All groups benefited from training, with decreases in anxiety and worry, and no significant differences between groups. The replacement of worry with different forms of positive ideation, even when unrelated to the content of worry itself, seems to have similar beneficial effects, suggesting that any form of positive ideation can be used to effectively counter worry. PMID:26802793

  13. HUBBLE CAPTURES AN EXTRAORDINARY AND POWERFUL ACTIVE GALAXY

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Resembling a swirling witch's cauldron of glowing vapors, the black hole-powered core of a nearby active galaxy appears in this colorful NASA Hubble Space Telescope image. The galaxy lies 13 million light-years away in the southern constellation Circinus. This galaxy is designated a type 2 Seyfert, a class of mostly spiral galaxies that have compact centers and are believed to contain massive black holes. Seyfert galaxies are themselves part of a larger class of objects called Active Galactic Nuclei or AGN. AGN have the ability to remove gas from the centers of their galaxies by blowing it out into space at phenomenal speeds. Astronomers studying the Circinus galaxy are seeing evidence of a powerful AGN at the center of this galaxy as well. Much of the gas in the disk of the Circinus spiral is concentrated in two specific rings -- a larger one of diameter 1,300 light-years, which has already been observed by ground-based telescopes, and a previously unseen ring of diameter 260 light-years. In the Hubble image, the smaller inner ring is located on the inside of the green disk. The larger outer ring extends off the image and is in the plane of the galaxy's disk. Both rings are home to large amounts of gas and dust as well as areas of major 'starburst' activity, where new stars are rapidly forming on timescales of 40 - 150 million years, much shorter than the age of the entire galaxy. At the center of the starburst rings is the Seyfert nucleus, the believed signature of a supermassive black hole that is accreting surrounding gas and dust. The black hole and its accretion disk are expelling gas out of the galaxy's disk and into its halo (the region above and below the disk). The detailed structure of this gas is seen as magenta-colored streamers extending towards the top of the image. In the center of the galaxy and within the inner starburst ring is a V-shaped structure of gas. The structure appears whitish-pink in this composite image, made up of four filters. Two

  14. USE OF COAL DRYING TO REDUCE WATER CONSUMED IN PULVERIZED COAL POWER PLANTS

    SciTech Connect

    Edward K. Levy; Hugo Caram; Zheng Yao; Gu Feng

    2004-01-01

    This is the fourth Quarterly Report for this project. The background and technical justification for the project are described, including potential benefits of reducing fuel moisture, prior to firing in a pulverized coal boiler. A description is given of the equipment, instrumentation and procedures being used for the fluidized bed drying experiments. Experimental data were obtained during this last quarter on the effects of particle size on drying rate for a North Dakota lignite. Other experiments looked at drying a PRB coal. The tests comparing drying rates with lignite particles of different diameters were carried out with particle top sizes from 2 to 9.5 mm and covered a range of air velocities. The results show that drying rate increased with air velocity, but that, within the accuracy of the data, the data for all four particle size distributions follow the same curve. This suggests the higher drying rates associated with the larger particles are due to higher air velocities and not to any inherently different drying rates due to particle size. The drying data with the PRB coal show qualitatively similar behavior to that observed with lignite. However, quantitative comparisons of the drying rate data obtained so far for the two coals show the PRB dried at rates which were 14 to 20 percent lower than the lignite, for comparable process conditions. The equilibrium relationship between relative humidity and coal moisture was refined using a correction for temperature. This reduced the scatter in the coal moisture versus relative humidity data and improved the predictions made with the first principle drying model.

  15. Optical trapping of nanoparticles with significantly reduced laser powers by using counter-propagating beams (Presentation Recording)

    NASA Astrophysics Data System (ADS)

    Zhao, Chenglong; LeBrun, Thomas W.

    2015-08-01

    Gold nanoparticles (GNP) have wide applications ranging from nanoscale heating to cancer therapy and biological sensing. Optical trapping of GNPs as small as 18 nm has been successfully achieved with laser power as high as 855 mW, but such high powers can damage trapped particles (particularly biological systems) as well heat the fluid, thereby destabilizing the trap. In this article, we show that counter propagating beams (CPB) can successfully trap GNP with laser powers reduced by a factor of 50 compared to that with a single beam. The trapping position of a GNP inside a counter-propagating trap can be easily modulated by either changing the relative power or position of the two beams. Furthermore, we find that under our conditions while a single-beam most stably traps a single particle, the counter-propagating beam can more easily trap multiple particles. This (CPB) trap is compatible with the feedback control system we recently demonstrated to increase the trapping lifetimes of nanoparticles by more than an order of magnitude. Thus, we believe that the future development of advanced trapping techniques combining counter-propagating traps together with control systems should significantly extend the capabilities of optical manipulation of nanoparticles for prototyping and testing 3D nanodevices and bio-sensing.

  16. Method and apparatus for powering an electrodeless lamp with reduced radio frequency interference

    DOEpatents

    Simpson, J.E.

    1999-06-08

    An electrodeless lamp waveguide structure includes tuned absorbers for spurious RF signals. A lamp waveguide with an integral frequency selective attenuation includes resonant absorbers positioned within the waveguide to absorb spurious out-of-band RF energy. The absorbers have a negligible effect on energy at the selected frequency used to excite plasma in the lamp. In a first embodiment, one or more thin slabs of lossy magnetic material are affixed to the sidewalls of the waveguide at approximately one quarter wavelength of the spurious signal from an end wall of the waveguide. The positioning of the lossy material optimizes absorption of power from the spurious signal. In a second embodiment, one or more thin slabs of lossy magnetic material are used in conjunction with band rejection waveguide filter elements. In a third embodiment, one or more microstrip filter elements are tuned to the frequency of the spurious signal and positioned within the waveguide to couple and absorb the spurious signal's energy. All three embodiments absorb negligible energy at the selected frequency and so do not significantly diminish the energy efficiency of the lamp. 18 figs.

  17. Method and apparatus for powering an electrodeless lamp with reduced radio frequency interference

    DOEpatents

    Simpson, James E.

    1999-01-01

    An electrodeless lamp waveguide structure includes tuned absorbers for spurious RF signals. A lamp waveguide with an integral frequency selective attenuation includes resonant absorbers positioned within the waveguide to absorb spurious out-of-band RF energy. The absorbers have a negligible effect on energy at the selected frequency used to excite plasma in the lamp. In a first embodiment, one or more thin slabs of lossy magnetic material are affixed to the sidewalls of the waveguide at approximately one quarter wavelength of the spurious signal from an end wall of the waveguide. The positioning of the lossy material optimizes absorption of power from the spurious signal. In a second embodiment, one or more thin slabs of lossy magnetic material are used in conjunction with band rejection waveguide filter elements. In a third embodiment, one or more microstrip filter elements are tuned to the frequency of the spurious signal and positioned within the waveguide to couple and absorb the spurious signal's energy. All three embodiments absorb negligible energy at the selected frequency and so do not significantly diminish the energy efficiency of the lamp.

  18. Optimizing Techology to Reduce Mercury and Acid Gas Emissions from Electric Power Plants

    SciTech Connect

    Jeffrey C. Quick; David E. Tabet; Sharon Wakefield; Roger L. Bon

    2004-01-31

    More than 56,000 coal quality data records from five public data sets have been selected for use in this project. These data will be used to create maps showing where coals with low mercury and acid-gas emissions might be found for power plants classified by air-pollution controls. Average coal quality values, calculated for 51,156 commercial coals by U.S. county-of-origin, are listed in the appendix. Coal moisture values are calculated for commercially shipped coal from 163 U.S. counties, where the raw assay data (including mercury and chlorine values) are reported on a dry basis. The calculated moisture values are verified by comparison with observed moisture values in commercial coal. Moisture in commercial U.S. coal shows provincial variation. For example, high volatile C bituminous rank coal from the Interior province has 3% to 4% more moisture than equivalent Rocky Mountain province coal. Mott-Spooner difference values are calculated for 4,957 data records for coals collected from coal mines and exploration drill holes. About 90% of the records have Mott-Spooner difference values within {+-}250 Btu/lb.

  19. A photonic frequency octo-tupler with reduced RF drive power and extended spurious sideband suppression

    NASA Astrophysics Data System (ADS)

    Hasan, Mehedi; Hall, Trevor J.

    2016-07-01

    A Mach-Zehnder interferometer with each arm containing a pair of Mach-Zehnder modulators (MZM) in series is proposed as a means of optoelectronic frequency multiplication (octo-tupling and 24-tupling). All harmonics including the carrier are suppressed except those with order equal to an odd multiple of four. The circuit requires no electrical or optical filters. There is no requirement to carefully adjust the modulation index to achieve correct operation of the octo-tupler. A transfer matrix representation is used to describe the operation of the architecture. The theoretical predictions are validated by simulations performed using an industry standard software tool. The simulations also allow an assessment of the impact on the circuit operation of deviations from the ideal of its components such as the finite extinction ratio of the MZMs, power imbalances and phase error at the couplers and phase error of the applied RF signals. Finally, a comparison is made with an alternative functionally equivalent single-stage parallel MZM circuit. One finding is that the intrinsic conversion efficiency of the proposed circuit is improved by 3 dB over the alternative. The proposed circuit is suitable for integration in material platforms supporting linear electro-optic modulation such as LiNbO3, silicon, III-V or hybrid technology.

  20. Baroreflex Activation Therapy in Heart Failure With Reduced Ejection Fraction: Available Data and Future Perspective.

    PubMed

    Halbach, Marcel; Fritz, Thorsten; Madershahian, Navid; Pfister, Roman; Reuter, Hannes

    2016-04-01

    Progression of heart failure with reduced ejection fraction (HFrEF) is promoted by sympathovagal imbalance. Baroreflex activation therapy, i.e., electrical stimulation of baroreceptors at the carotid sinus, can restore sympathovagal balance. Large animal studies of baroreflex activation therapy revealed improvements in cardiac function, susceptibility to ventricular arrhythmias, and a survival benefit as compared to untreated controls. Recently, the first randomized and controlled trial of optimal medical and device therapy alone or plus baroreflex activation therapy in patients suffering from HFrEF was published. It demonstrated a reasonable safety profile in this severely ill patient population. Moreover, the study found significant improvements in New York Heart Association class, quality of life, 6-min walk distance, and NT-proBNP levels. This review provides an overview on baroreflex activation therapy for the treatment of HFrEF-from the concept and preclinical findings to most recent clinical data and upcoming trials. PMID:26879389

  1. Dioxin mediates downregulation of the reduced folate carrier transport activity via the arylhydrocarbon receptor signalling pathway

    SciTech Connect

    Halwachs, Sandra; Lakoma, Cathleen; Gebhardt, Rolf; Schaefer, Ingo; Seibel, Peter; Honscha, Walther

    2010-07-15

    Dioxins such as 2,3,7,8-tetrachlordibenzo-p-dioxin (TCDD) are common environmental contaminants known to regulate several genes via activation of the transcription factor aryl hydrocarbon receptor (AhR) associated with the development of numerous adverse biological effects. However, comparatively little is known about the molecular mechanisms by which dioxins display their toxic effects in vertebrates. The 5' untranslated region of the hepatocellular Reduced folate carrier (Rfc1; Slc19a1) exhibits AhR binding sites termed dioxin responsive elements (DRE) that have as yet only been found in the promoter region of prototypical TCDD target genes. Rfc1 mediated transport of reduced folates and antifolate drugs such as methotrexate (MTX) plays an essential role in physiological folate homeostasis and MTX cancer chemotherapy. In order to determine whether this carrier represents a target gene of dioxins we have investigated the influence of TCDD on functional Rfc1 activity in rat liver. Pre-treatment of rats with TCDD significantly diminished hepatocellular Rfc1 uptake activity in a time- and dose-dependent manner. In further mechanistic studies we demonstrated that this reduction was due to TCDD-dependent activation of the AhR signalling pathway. We additionally showed that binding of the activated receptor to DRE motifs in the Rfc1 promoter resulted in downregulation of Rfc1 gene expression and reduced carrier protein levels. As downregulation of pivotal Rfc1 activity results in functional folate deficiency associated with an elevated risk of cardiovascular diseases or carcinogenesis, our results indicate that deregulation of this essential transport pathway represents a novel regulatory mechanism how dioxins display their toxic effects through the Ah receptor.

  2. High intensity focused ultrasound sonothrombolysis: the use of perfluorocarbon droplets to achieve clot lysis at reduced acoustic powers

    PubMed Central

    Pajek, Daniel; Burgess, Alison; Huang, Yuexi; Hynynen, Kullervo

    2014-01-01

    The purpose of this study was to evaluate use of intravascular perfluorocarbon (PFC) droplets to reduce the sonication powers required to achieve clot lysis using high intensity focused ultrasound (HIFU). HIFU with droplets was initially applied to blood clots in an in vitro flow apparatus and inertial cavitation thresholds were determined. An embolic model for ischemic stroke was used to demonstrate the feasibility of this technique in vivo. Recanalization with intravascular droplets was achieved in vivo at 24±5% of the sonication power without droplets. Rabbits receiving 1 ms pulsed sonication during continuous intravascular droplet infusion recanalized in 71% of cases (p=0.041 vs controls). Preliminary experiments showed that damage was contained to the ultrasonic focus, suggesting that safe treatments would be possible with a more tightly focused hemispherical array that allows the whole focus to be placed inside of the main arteries in the human brain. PMID:25023095

  3. Application of Feedforward Adaptive Active-Noise Control for Reducing Blade Passing Noise in Centrifugal Fans

    NASA Astrophysics Data System (ADS)

    WU, J.-D.; BAI, M. R.

    2001-02-01

    This paper describes two configurations of feedforward adaptive active-noise control (ANC) technique for reducing blade passing noise in centrifugal fans. In one configuration, the control speaker is installed at the cut-off region of the fan, while in the other configuration at the exit duct. The proposed ANC system is based on the filtered-x least-mean-squares (FXLMS) algorithm with multi-sine synthesized reference signal and frequency counting and is implemented by using a digital signal processor (DSP). Experiments are carried out to evaluate the proposed system for reducing the noise at the blade passing frequency (BPF) and its harmonics at various flow speeds. The results of the experiment indicated that the ANC technique is effective in reducing the blade passing noise for two configurations by using the feedforward adaptive control.

  4. Synovial sarcoma cell lines showed reduced DNA repair activity and sensitivity to a PARP inhibitor.

    PubMed

    Yamasaki, Hiroyuki; Miyamoto, Mamiko; Yamamoto, Yuki; Kondo, Tadashi; Watanabe, Toshiki; Ohta, Tsutomu

    2016-08-01

    Synovial sarcoma is a soft-tissue sarcoma and a rare type of cancer. Unfortunately, effective chemotherapies for synovial sarcomas have not been established. In this report, we show that synovial sarcoma cell lines have reduced repair activity for DNA damage induced by ionizing radiation (IR) and a topoisomerase II inhibitor (etoposide). We also observed reduced recruitment of RAD51 homologue (S. cerevisiae; RAD51) at sites of double-strand breaks (DSBs) in synovial sarcoma cell lines that had been exposed to IR. These findings showed that synovial sarcoma cell lines are defective in homologous recombination (HR) repair. Furthermore, we found that a poly-(ADP-ribose) polymerase (PARP) inhibitor (AZD2281; olaparib) effectively reduced the growth of synovial sarcoma cell lines in the presence of an alkylating agent (temozolomide). Our findings offer evidence that treatment combining a PARP inhibitor and an alkylating agent could have therapeutic benefits in the treatment of synovial sarcoma. PMID:27353471

  5. Reduced cytochrome oxidase activity in the retrosplenial cortex after lesions to the anterior thalamic nuclei.

    PubMed

    Mendez-Lopez, Magdalena; Arias, Jorge L; Bontempi, Bruno; Wolff, Mathieu

    2013-08-01

    The anterior thalamic nuclei (ATN) make a critical contribution to hippocampal system functions. Growing experimental work shows that the effects of ATN lesions often resemble those of hippocampal lesions and both markedly reduce the expression of immediate-early gene markers in the retrosplenial cortex, which still appears normal by standard histological means. This study shows that moderate ATN damage was sufficient to produce severe spatial memory impairment as measured in a radial-arm maze. Furthermore, ATN rats exhibited reduced cytochrome oxidase activity in the most superficial cortical layers of the granular retrosplenial cortex, and, to a lesser extent, in the anterior cingulate cortex. By contrast, no change in cytochrome oxidase activity was observed in other limbic cortical regions or in the hippocampal formation. Altogether our results indicate that endogenous long-term brain metabolic capacity within the granular retrosplenial cortex is compromised by even limited ATN damage. PMID:23660649

  6. Shipwreck rates and tree rings suggest reduced North Atlantic tropical cyclone activity during the Maunder Minimum.

    NASA Astrophysics Data System (ADS)

    Harley, G. L.; Trouet, V.; Dominguez Delmas, M.

    2014-12-01

    The observational record of North Atlantic TCs is too short to inform our understanding of decadal-scale climatic controls on TC regimes. We combined two new annual-resolution proxies of Atlantic storm activity to extend the observational TC record back to the 16th Century. A tree-growth suppression chronology (1707-2010 CE) from the Florida Keys, U.S.A. captures 91% of observed North Atlantic TCs (1850-2010 CE) and shares significant peak events with a documentary time series of Spanish shipwrecks in the Caribbean (1495-1820). Decadal-scale shipwreck rates were lowest during the Maunder Minimum (ca. 1645-1715), indicating that cooler Atlantic sea surface temperatures (SSTs) during this period reduced Caribbean TC activity. Our results support global-scale climate proxy data and suggest that cooler tropical Atlantic SSTs and a generally negative mode of the North Atlantic Oscillation during the Little Ice Age reduced TC frequency.

  7. Activated microglia in acute encephalopathy with biphasic seizures and late reduced diffusion.

    PubMed

    Fujita, Yuji; Takanashi, Jun-Ichi; Takei, Haruka; Ota, Setsuo; Fujii, Katsunori; Sakuma, Hiroshi; Hayashi, Masaharu

    2016-07-15

    Acute encephalopathy with biphasic seizures and late reduced diffusion (AESD) is the most common subtype of infectious pediatric encephalopathy in Japan. The exact pathogenesis of and the best therapeutic strategy for AESD are uncertain. We firstly performed a brain biopsy in a 2-year-old boy with AESD associated with RS viral infection, which revealed activated ameoboid microglia accumulation around degenerated neuron, and astrogliosis in the affected cortex. Glutamate released from activated microglia may play an important role in the pathogenesis of AESD, which is compatible with the previous report of magnetic resonance spectroscopy showing elevated glutamate. PMID:27288783

  8. Reduced Cortical Activity Impairs Development and Plasticity after Neonatal Hypoxia Ischemia

    PubMed Central

    Ranasinghe, Sumudu; Or, Grace; Wang, Eric Y.; Ievins, Aiva; McLean, Merritt A.; Niell, Cristopher M.; Chau, Vann; Wong, Peter K. H.; Glass, Hannah C.; Sullivan, Joseph

    2015-01-01

    Survivors of preterm birth are at high risk of pervasive cognitive and learning impairments, suggesting disrupted early brain development. The limits of viability for preterm birth encompass the third trimester of pregnancy, a “precritical period” of activity-dependent development characterized by the onset of spontaneous and evoked patterned electrical activity that drives neuronal maturation and formation of cortical circuits. Reduced background activity on electroencephalogram (EEG) is a sensitive marker of brain injury in human preterm infants that predicts poor neurodevelopmental outcome. We studied a rodent model of very early hypoxic–ischemic brain injury to investigate effects of injury on both general background and specific patterns of cortical activity measured with EEG. EEG background activity is depressed transiently after moderate hypoxia–ischemia with associated loss of spindle bursts. Depressed activity, in turn, is associated with delayed expression of glutamate receptor subunits and transporters. Cortical pyramidal neurons show reduced dendrite development and spine formation. Complementing previous observations in this model of impaired visual cortical plasticity, we find reduced somatosensory whisker barrel plasticity. Finally, EEG recordings from human premature newborns with brain injury demonstrate similar depressed background activity and loss of bursts in the spindle frequency band. Together, these findings suggest that abnormal development after early brain injury may result in part from disruption of specific forms of brain activity necessary for activity-dependent circuit development. SIGNIFICANCE STATEMENT Preterm birth and term birth asphyxia result in brain injury from inadequate oxygen delivery and constitute a major and growing worldwide health problem. Poor outcomes are noted in a majority of very premature (<25 weeks gestation) newborns, resulting in death or life-long morbidity with motor, sensory, learning, behavioral

  9. Aircraft panel with sensorless active sound power reduction capabilities through virtual mechanical impedances

    NASA Astrophysics Data System (ADS)

    Boulandet, R.; Michau, M.; Micheau, P.; Berry, A.

    2016-01-01

    This paper deals with an active structural acoustic control approach to reduce the transmission of tonal noise in aircraft cabins. The focus is on the practical implementation of the virtual mechanical impedances method by using sensoriactuators instead of conventional control units composed of separate sensors and actuators. The experimental setup includes two sensoriactuators developed from the electrodynamic inertial exciter and distributed over an aircraft trim panel which is subject to a time-harmonic diffuse sound field. The target mechanical impedances are first defined by solving a linear optimization problem from sound power measurements before being applied to the test panel using a complex envelope controller. Measured data are compared to results obtained with sensor-actuator pairs consisting of an accelerometer and an inertial exciter, particularly as regards sound power reduction. It is shown that the two types of control unit provide similar performance, and that here virtual impedance control stands apart from conventional active damping. In particular, it is clear from this study that extra vibrational energy must be provided by the actuators for optimal sound power reduction, mainly due to the high structural damping in the aircraft trim panel. Concluding remarks on the benefits of using these electrodynamic sensoriactuators to control tonal disturbances are also provided.

  10. Strategies to Bulk Half-Heusler Nanocomposites with Simultaneously Enhanced Power Factor and Reduced Thermal Conductivity

    NASA Astrophysics Data System (ADS)

    Poudeu, Pierre Ferdinand

    2011-03-01

    Among promising thermoelectric materials for power generation, half-Heusler (HH) phases with general compositions TNiSn and TCoSb (T = Ti, Zr, Hf) have attracted tremendous attention not only because they involve abundant and environmentally friendly elements, but also due to their combination of large Seebeck coefficients with moderately low electrical resistivities. However, the ability to synthesize HH based materials with decent figures of merit (ZT> 1) hasbeenjeopardizedbytheirverylargethermalconductivities . StrategiestoreducethethermalconductivityofHHphasesfocusingonmassfluctuationphononscatteringviasolidsolutionalloyingorphononscatteringatgrainboundariesandinterfacesinHHphaseswithembeddedpre - synthesizednanoparticleshavefailedtogeneratematerialswithhighfiguresofmeritduetosimultaneousreductionsinthepowerfactor . Here , weintroduceinnovativeapproachestorevolutionaryincreasesinthefigureofmeritofHHbasedmaterialsthroughsimultaneouslargeenhancementofthepowerfactoranddrasticreductioninthethermalconductivity . Ourstrategyisfocusedonatomic - scalestructuralengineeringoftheHHmatrixthroughtheconfinementoffull - Heusler (FH) inclusionphasesonthelatticeconstantlength - scale . Emphasiswillbeplacedonthen - typeZr 0.25 Hf 0.75 Ni 1+x Sn 1-y Pn y andTi 0.5 Zr 0.5 Ni 1+x Sn 1-y Pn y aswellasthep - typeTi 0.5 Zr 0.5 Co 1+x Pn 1-y Sn y , (Pn = Sb, Bi) nanocomposites. We will discuss the underlying mechanism for the formation of half-Heusler/full-Heusler (HH/FH) nanocomposites with coherent matrix/inclusion interfaces. The role of synthetic and processing methods; and size, dispersion and mole fraction of the FH inclusions on the thermoelectric performance of bulk HH/FH nanocomposites will be assessed by combining transmission electron microscopy studies with thermal and electronic charge transport data. Financial support from DARPA contract # HR 0011-08-1-0084 is greatly acknowledged. This work made use of the laser flash diffusivity apparatus (Netzsch-LFA457) purchased with

  11. Increased water activity reduces the thermal resistance of Salmonella enterica in peanut butter.

    PubMed

    He, Yingshu; Li, Ye; Salazar, Joelle K; Yang, Jingyun; Tortorello, Mary Lou; Zhang, Wei

    2013-08-01

    Increased water activity in peanut butter significantly (P < 0.05) reduced the heat resistance of desiccation-stressed Salmonella enterica serotypes treated at 90 °C. The difference in thermal resistance was less notable when strains were treated at 126 °C. Using scanning electron microscopy, we observed minor morphological changes of S. enterica cells resulting from desiccation and rehydration processes in peanut oil. PMID:23728806

  12. Thermophysical and mechanical properties of Fe-(8-9)%Cr reduced activation steels

    SciTech Connect

    Zinkle, S.J.; Robertson, J.P.; Klueh, R.L.

    1998-09-01

    The key thermophysical and mechanical properties for 8--9%Cr reduced activation ferritic/martensitic steels are summarized, including temperature-dependent tensile properties in the unirradiated and irradiated conditions, stress-rupture behavior, elastic constants, thermal conductivity, thermal expansion, specific heat, and ductile-to-brittle transition temperature. The estimated lower and upper temperatures limits for structural applications are 250 and 550 C due to radiation hardening/embrittlement and thermal creep considerations, respectively.

  13. Overexpression of α-synuclein simultaneously increases glutamate NMDA receptor phosphorylation and reduces glucocerebrosidase activity.

    PubMed

    Yang, Junfeng; Hertz, Ellen; Zhang, Xiaoqun; Leinartaité, Lina; Lundius, Ebba Gregorsson; Li, Jie; Svenningsson, Per

    2016-01-12

    Progressive accumulation of α-synuclein (α-syn)-containing protein aggregates throughout the nervous system is a pathological hallmark of Parkinson's disease (PD). The mechanisms whereby α-syn exerts neurodegeneration remain to be fully understood. Here we show that overexpression of α-syn in transgenic mice leads to increased phosphorylation of glutamate NMDA receptor (NMDAR) subunits NR1 and NR2B in substantia nigra and striatum as well as reduced glucocerebrosidase (GCase) levels. Similarly, molecular studies performed in mouse N2A cells stably overexpressing human α-syn ((α-syn)N2A) showed that phosphorylation states of the same NMDAR subunits were increased, whereas GCase levels and lysosomal GCase activity were reduced. (α-syn)N2A cells showed an increased sensitivity to neurotoxicity towards 6-hydroxydopamine and NMDA. However, wildtype N2A, but not (α-syn)N2A cells, showed a further reduction in viability when co-incubated with 6-hydroxydopamine and the lysosomal inhibitors NH4Cl and leupeptin, suggesting that α-syn per se perturbs lysosomal functions. NMDA treatment reduced lysosomal GCase activity to the same extent in (α-syn)N2A cells as in wildtype N2A cells, indicating that the α-syn-dependent difference in NMDA neurotoxicity is unrelated to an altered GCase activity. Nevertheless, these data provide molecular evidence that overexpression of α-syn simultaneously induces two potential neurotoxic hits by increasing glutamate NMDA receptor phosphorylation, consistent with increased NMDA receptors functionality, and reducing GCase activity. PMID:26610904

  14. Activation of innate immunity to reduce lung metastases in breast cancer.

    PubMed

    Jordan, Julie L; Nowak, A; Lee, T D G

    2010-05-01

    Breast cancer continues to be one of the leading causes of cancer death in women. Mortality is primarily due to the development of metastases. Although therapies exist, they lack efficacy in preventing metastatic growth. As a result, novel agents are being investigated. In particular, treatments that target the immune system are being examined as potential anti-neoplastic agents. Cordyceps sinensis (Cs) is a fungus that has been used for over 2,000 years in China as a treatment for a variety of conditions including neoplasms. The available evidence suggests that efficacy of Cs as an anti-neoplastic therapeutic agent is related to a role as an activator of innate immune responses. The objectives of this study were: to investigate the ability of Cs to activate macrophages to produce factors that will induce protective responses against tumour growth; to study the ability of Cs to reduce primary tumour growth in vivo; and to examine the ability of Cs to reduce lung metastasis growth in vivo. We found that oral Cs does not reduce primary tumour growth but can reduce lung metastasis occurrence in a surgical excision model of metastatic mammary carcinoma. The evidence we have shown to date suggests that the reduction in metastases growth may be due to the effects of macrophage-derived factors on tumour cell cycle. PMID:19956948

  15. Calcaneal Quantitative Ultrasound Indicates Reduced Bone Status Among Physically Active Adult Forager-Horticulturalists.

    PubMed

    Stieglitz, Jonathan; Madimenos, Felicia; Kaplan, Hillard; Gurven, Michael

    2016-03-01

    Sedentary lifestyle contributes to osteoporosis and fragility fracture risks among modern humans, but whether such risks are prevalent in physically active preindustrial societies with lower life expectancies is unclear. Osteoporosis should be readily observable in preindustrial societies if it was regularly experienced over human history. In this study of 142 older adult Tsimane forager-horticulturalists (mean age ± SD, 62.1 ± 8.6 years; range, 50 to 85 years; 51% female) we used calcaneal quantitative ultrasonography (qUS) to assess bone status, document prevalence of adults with reduced bone status, and identify factors (demographic, anthropometric, immunological, kinesthetic) associated with reduced bone status. Men (23%) are as likely as women (25%) to have reduced bone status, although age-related decline in qUS parameters is attenuated for men. Adiposity and fat-free mass positively co-vary with qUS parameters for women but not men. Leukocyte count is inversely associated with qUS parameters controlling for potential confounders; leukocyte count is positively correlated within adults over time, and adults with persistently low counts have higher adjusted qUS parameters (6% to 8%) than adults with a high count. Reduced bone status characteristic of osteoporosis is common among active Tsimane with minimal exposure to osteoporosis risk factors found in industrialized societies, but with energetic constraints and high pathogen burden. © 2015 American Society for Bone and Mineral Research. PMID:26460548

  16. Enhanced performance of sulfate reducing bacteria based biocathode using stainless steel mesh on activated carbon fabric electrode.

    PubMed

    Sharma, Mohita; Jain, Pratiksha; Varanasi, Jhansi L; Lal, Banwari; Rodríguez, Jorge; Lema, Juan M; Sarma, Priyangshu M

    2013-12-01

    An anoxic biocathode was developed using sulfate-reducing bacteria (SRB) consortium on activated carbon fabric (ACF) and the effect of stainless steel (SS) mesh as additional current collector was investigated. Improved performance of biocathode was observed with SS mesh leading to nearly five folds increase in power density (from 4.79 to 23.11 mW/m(2)) and threefolds increase in current density (from 75 to 250 mA/m(2)). Enhanced redox currents and lower Tafel slopes observed from cyclic voltammograms of ACF with SS mesh indicated the positive role of uniform electron collecting points. Differential pulse voltammetry technique was employed as an additional tool to assess the redox carriers involved in bioelectrochemical reactions. SRB biocathode was also tested for reduction of volatile fatty acids (VFA) present in the fermentation effluent stream and the results indicated the possibility of integration of this system with anaerobic fermentation for efficient product recovery. PMID:24161648

  17. COIL power extraction enhanced by reducing/eliminating iodine clusters in a high Mach number nitrogen mixing nozzle

    NASA Astrophysics Data System (ADS)

    Marshall, J.; Healey, K.; Croker, B.; Kendrick, K.; Yang, T. T.; Hsia, Y. C.; Dickerson, R. A.; Forman, L.

    2006-02-01

    Heterogeneous iodine cluster formation has been identified as the responsible factor resulting in large iodine titration requirements for Boeing's first high Mach number nitrogen ejector nozzle. A solution employing geometrically produced aerodynamic heating in the flow was envisioned to break up these clusters. Horizontal and vertical wire arrays (cluster busters) placed downstream of the nozzle exit plane (NEP) have been shown to significantly reduce the optimal iodine titration and to greatly improve the power extraction efficiency of the Chemical Oxygen-Iodine Laser utilizing this first generation ejector nozzle.

  18. Low-power hardware implementation of movement decoding for brain computer interface with reduced-resolution discrete cosine transform.

    PubMed

    Minho Won; Albalawi, Hassan; Xin Li; Thomas, Donald E

    2014-01-01

    This paper describes a low-power hardware implementation for movement decoding of brain computer interface. Our proposed hardware design is facilitated by two novel ideas: (i) an efficient feature extraction method based on reduced-resolution discrete cosine transform (DCT), and (ii) a new hardware architecture of dual look-up table to perform discrete cosine transform without explicit multiplication. The proposed hardware implementation has been validated for movement decoding of electrocorticography (ECoG) signal by using a Xilinx FPGA Zynq-7000 board. It achieves more than 56× energy reduction over a reference design using band-pass filters for feature extraction. PMID:25570284

  19. Apparatus for improving gasoline comsumption, power and reducing emission pollutants of internal combustion engines

    SciTech Connect

    Piedrafita, R.

    1986-02-18

    This patent describes an apparatus for improving performance and reducing fuel comsumption and emission pollutants from an internal combustion gasoline engine. This apparatus consists of: 1.) an internal combustion gasoline engine having, in part, an intake manifold and an exhaust manifold where the exhaust manifold is modified to include a manifold exhaust port; 2.) a modified internal combustion engine carburetor connected to the intake manifold on the engine; 3.) a positive crankcase ventilation valve (PCV) which has an input port conventionally connected to the internal combustion engine and also has a PCV output port; 4.) an automobile fuel pump having an input connected to a conventional fuel tank and having a fuel pump output port; 5.) a thermic reactor; 6.) a thermic reactor air cleaner pneumatically connected to the clean air input port on the thermic reactor; 7.) a catalytic gas injector; 8.) a fuel regulator/restrictor consisting of a solid block having a fuel pump input port and a carburetor output port.

  20. USE OF COAL DRYING TO REDUCE WATER CONSUMED IN PULVERIZED COAL POWER PLANTS

    SciTech Connect

    Edward K. Levy; Hugo Caram; Zheng Yao; Gu Feng

    2003-10-01

    This is the third Quarterly Report for this project. The background and technical justification for the project are described, including potential benefits of reducing fuel moisture, prior to firing in a pulverized coal boiler. A description is given of the equipment, instrumentation and procedures being used for the fluidized bed drying experiments. Laboratory data are presented on the effects of bed depth on drying rate. These show that drying rate decreased strongly with an increase in bed depth as the settled bed depth varied from 0.25 to 0.65 m. These tests were performed with North Dakota lignite having a 6.35 mm (1/4 inch) top size, constant inlet air and heater surface temperatures, constant rate of heat addition per unit initial mass of wet coal and constant superficial air velocity. A theoretical model of the batch dryer is described. This model uses the equations for conservation of mass and energy and empirical data on the relationship between relative humidity of the air and coal moisture content at equilibrium. Outputs of the model are coal moisture content, bed temperature, and specific humidity of the outlet air as functions of time. Preliminary comparisons of the model to laboratory drying data show very good agreement.

  1. USE OF COAL DRYING TO REDUCE WATER CONSUMED IN PULVERIZED COAL POWER PLANTS

    SciTech Connect

    Edward K. Levy

    2003-03-01

    This is the first Quarterly Report for this project. The background and technical justification for the project are described, including potential benefits of reducing fuel moisture, prior to firing in a pulverized coal boiler. A description is given of the equipment and instrumentation being used for the fluidized bed drying experiments. Results of fluidization and drying tests performed with North Dakota lignite, having a 6.35 mm (1/4 inch) top size, are presented. The experiments were performed with a 381 mm (15 inch) settled bed depth, with inlet air and in-bed heater surface temperatures of 44.3 C (110 F), and with the superficial air velocity ranging from 0.2 m/s to 1.4 m/s. Drying rate is shown to be a strong function of air velocity, increasing seven-fold from 0.2 m/s to 1.4 m/s. Increases in velocity from 0.75 m/s (minimum fluidization velocity) to 1.4 m/s resulted in a doubling of the drying rate.

  2. USE OF COAL DRYING TO REDUCE WATER CONSUMED IN PULVERIZED COAL POWER PLANTS

    SciTech Connect

    Edward K. Levy; Nenad Sarunac; Wei Zhang

    2004-10-01

    This is the seventh Quarterly Report for this project. The background and technical justification for the project are described, including potential benefits of reducing fuel moisture, prior to firing in a pulverized coal boiler. Coal drying experiments were performed with lignite and Powder River Basin coals to determine the effects of inlet air moisture level on the equilibrium relationship between coal moisture and exit air relative humidity and temperature. The results show that, for lignite, there is a slight dependence of equilibrium moisture on inlet humidity level. However, the equilibrium relationship for PRB coal appears to be independent of inlet air humidity level. The specific equilibrium model used for computing lignite coal dryer performance has a significant effect on the prediction accuracy for exit air relative humidity; but its effects on predicted coal product moisture, exit air temperature and specific humidity are minimal. Analyses were performed to determine the effect of lignite product moisture on unit performance for a high temperature drying system. With this process design, energy for drying is obtained from the hot flue gas entering the air preheater and the hot circulating cooling water leaving the steam condenser. Comparisons were made to the same boiler operating with lignite which had been dried off-site.

  3. Voluntary access to a warm plate reduces hyperactivity in activity-based anorexia.

    PubMed

    Hillebrand, Jacquelien J G; de Rijke, Corine E; Brakkee, Jan H; Kas, Martien J H; Adan, Roger A H

    2005-06-01

    Activity-based anorexia (ABA) is considered an animal model of anorexia nervosa. In ABA, scheduled feeding in combination with voluntary wheel running leads to hyperactivity, reduced food intake, severe body weight loss and hypothermia. In this study it was investigated whether hyperactivity in ABA could be reduced by introducing a warm plate (which was voluntary accessible and did not influence ambient temperature) into a part of the cage. In ad libitum fed rats, the presence of the warm plate did not influence body temperature, running wheel activity (RWA), body weight or food intake. During ABA, however, rats preferred the warm plate and hypothermia was prevented, while hyperactivity and body weight loss were significantly reduced when compared to ABA rats without a plate. Correlation analysis revealed a significant association between basal body temperature and RWA during the light phase in ABA rats. However, there was no evidence that initiation of light phase RWA was a result of hypothermia. These data suggest that ABA rats prefer to prevent hypothermia passively by choosing a warm plate rather than actively regulating body temperature by hyperactivity. PMID:15924912

  4. PGE2 Reduces MMP-14 and Increases Plasminogen Activator Inhibitor-1 in Cardiac Fibroblasts

    PubMed Central

    Kassem, Kamal M.; Clevenger, Margarette H.; Szandzik, David L.; Peterson, Edward; Harding, Pamela

    2014-01-01

    Prostaglandin E2 (PGE2) is elevated during cardiac injury and we have previously shown that mice lacking the PGE EP4 receptor display dilated cardiomyopathy (DCM) with increased expression of the membrane type matrix metalloproteinase, MMP-14. We thus hypothesized that PGE2 regulates expression of MMP-14 and also affects fibroblast migration. Primary cultures of neonatal rat ventricular fibroblasts (NVFs) were used to test the effects of PGE2. Gene and protein expression was assessed by real time RT-PCR and Western blot, MMP activity was determined by zymography and migration of NVF was assessed by motility in a transwell system. PGE2 reduced expression of MMP-14 and these effects were antagonized by an EP4 antagonist. An EP4 agonist mimicked the effect of PGE2. PGE2 also increased mRNA and protein levels of plasminogen activator inhibitor-1 (PAI-1), an inhibitor of MMP activation. However, PGE2-stimulation of PAI-1 was mediated by the EP1/EP3 receptor and not EP4. Migration of NVF was assessed by motility in a transwell system. Treatment of NVFs with PGE2 reduced the number of cells migrating towards 10% FCS. Treatment with the EP2 agonist also reduced migration but did not affect MMP-14 expression or PAI-1. Our results suggest that PGE2 utilizes different receptors and mechanisms to ultimately decrease MMP expression and NVF migration. PMID:25263346

  5. PGE2 reduces MMP-14 and increases plasminogen activator inhibitor-1 in cardiac fibroblasts.

    PubMed

    Kassem, Kamal M; Clevenger, Margarette H; Szandzik, David L; Peterson, Edward; Harding, Pamela

    2014-10-01

    Prostaglandin E2 (PGE2) is elevated during cardiac injury and we have previously shown that mice lacking the PGE2 EP4 receptor display dilated cardiomyopathy (DCM) with increased expression of the membrane type matrix metalloproteinase, MMP-14. We thus hypothesized that PGE2 regulates expression of MMP-14 and also affects fibroblast migration. Primary cultures of neonatal rat ventricular fibroblasts (NVFs) were used to test the effects of PGE2. Gene and protein expression was assessed by real time RT-PCR and Western blot, MMP activity was determined by zymography and migration of NVF was assessed by motility in a transwell system. PGE2 reduced expression of MMP-14 and these effects were antagonized by an EP4 antagonist. An EP4 agonist mimicked the effect of PGE2. PGE2 also increased mRNA and protein levels of plasminogen activator inhibitor-1 (PAI-1), an inhibitor of MMP activation. However, PGE2-stimulation of PAI-1 was mediated by the EP1/EP3 receptor and not EP4. Migration of NVF was assessed by motility in a transwell system. Treatment of NVFs with PGE2 reduced the number of cells migrating toward 10% FCS. Treatment with the EP2 agonist also reduced migration but did not affect MMP-14 expression or PAI-1. Our results suggest that PGE2 utilizes different receptors and mechanisms to ultimately decrease MMP expression and NVF migration. PMID:25263346

  6. Evaluation on Fatigue Crack Propagation of Reduced Activation Ferritic Steel (JLF-1) at High Temperature

    NASA Astrophysics Data System (ADS)

    Yoon, Han Ki; Kim, Sa Woong; Lee, Sang Pill; Katoh, Yutai; Kohyama, Akira

    Recently, reduced activation ferritic/martensitic steel, vanadium alloy and SiC/SiC composite are embossed for nuclear fusion reactor in accordance with the coolant. Especially, reduced activation ferritic/martensitic steel is very suitable material for nuclear fusion reactor, because it has low coefficient of thermal expansion and excellent heat conductivity. The objective of this study is to investigate fatigue crack propagation behavior in the Reduced Activation Ferritic Steel (JLF-1). The fatigue crack propagation behavior of the JLF-1 steel was investigated by the constant-amplitude loading test for the stress ratios R = 0.1, 0.3 and 0.5 respectively. The fatigue crack growth tests carried out at room temperature and 400°C for base metal and weld metal. The effects of stress ratio, test temperature, specimen size and TIG welding on the fatigue crack propagation behaviors for JLF-1 steel were discussed within the Paris law. Particularly, the fatigue crack propagation rate of a weld metal was similar to that of base metal at the stress ratio of 0.3. Also, the fatigue crack propagation rate of a half size specimen was similar to that of a full size specimen at the stress ratios of 0.1, 0.3 and 0.5 respectively. From this result, we can recognize that the fatigue crack propagation behavior of this material can be evaluated by using the half size specimens.

  7. Powerful Low-Frequency Vibrators for Active Seismology

    SciTech Connect

    Alekseev, A.S.; Chichinin, I.S.; Korneev, V.A.

    2003-12-01

    In the past two decades, active seismology studies in Russia have made use of powerful (40- and 100-ton) low-frequency vibrators. These sources create a force amplitude of up to 100 tons and function in the 1.5 3, 3 6, and 5 10 Hz frequency bands. The mobile versions of the vibrator have a force amplitude of 40 tons and a 6 12 Hz frequency band. Recording distances for the 100-ton vibrator are as large as 350 km, enabling the refracted waves to penetrate down to 50 km depths. Vibrator operation sessions are highly repeatable, having distinct summer or winter spectral patterns. A long profile of seismic records allows estimation of fault zone depths using changes in recorded spectra. Other applications include deep seismic profiling, seismic hazard mapping, structural testing, stress-induced anisotropy studies, seismic station calibration, and large-structure integrity testing. The theoretical description of the low-frequency vibrator is given in the appendices, which contain numerical examples.

  8. Eugenol dilates mesenteric arteries and reduces systemic BP by activating endothelial cell TRPV4 channels

    PubMed Central

    Peixoto-Neves, Dieniffer; Wang, Qian; Leal-Cardoso, Jose H; Rossoni, Luciana V; Jaggar, Jonathan H

    2015-01-01

    Background and Purpose Eugenol, a vanilloid molecule found in some dietary plants, relaxes vasculature in part via an endothelium-dependent process; however, the mechanisms involved are unclear. Here, we investigated the endothelial cell-mediated mechanism by which eugenol modulates rat mesenteric artery contractility and systemic BP. Experimental Approach The isometric tension of rat mesenteric arteries (size 200–300 μm) was measured using wire myography; non-selective cation currents (ICat) were recorded in endothelial cells using patch clamp electrophysiology. Mean arterial pressure (MAP) and heart rate (HR) were determined in anaesthetized rats. Key Results Eugenol relaxed endothelium-intact arteries in a concentration-dependent manner and this effect was attenuated by endothelium denudation. L-NAME, a NOS inhibitor, a combination of TRAM-34 and apamin, selective blockers of intermediate and small conductance Ca2+-activated K+ channels, respectively, and HC-067047, a TRPV4 channel inhibitor, but not indomethacin, a COX inhibitor, reduced eugenol-induced relaxation in endothelium-intact arteries. Eugenol activated HC-067047-sensitive ICat in mesenteric artery endothelial cells. Short interfering RNA (siRNA)-mediated TRPV4 knockdown abolished eugenol-induced ICat activation. An i.v. injection of eugenol caused an immediate, transient reduction in both MAP and HR, which was followed by prolonged, sustained hypotension in anaesthetized rats. This sustained hypotension was blocked by HC-067047. Conclusions and Implications Eugenol activates TRPV4 channels in mesenteric artery endothelial cells, leading to vasorelaxation, and reduces systemic BP in vivo. Eugenol may be therapeutically useful as an antihypertensive agent and is a viable molecular candidate from which to develop second-generation TRPV4 channel activators that reduce BP. PMID:25832173

  9. Enzymatic activation of cellulose acetate membrane for reducing of protein fouling.

    PubMed

    Koseoglu-Imer, Derya Y; Dizge, Nadir; Koyuncu, Ismail

    2012-04-01

    In this study, the surface of cellulose acetate (CA) ultrafiltration membrane was activated with serine protease (Savinase) enzyme to reduce protein fouling. Enzyme molecules were covalently immobilized with glutaraldehyde (cross-linking agent) onto the surface of CA membranes. The membrane activation was verified using filtration experiments and morphological analysis. Scanning electron microscopy (SEM) images and attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy of the activated membrane when compared with raw membrane were confirmed that the enzyme was immobilized onto the membrane surface. The immobilization efficiencies changed from 13.2 to 41.2% according to the enzyme ratios from 2.5 to 10.0 mg/mL. However, the permeability values decreased from 232±6 to 121±4 L/m(2) h bar with increasing enzyme concentration from 2.5 to 10.0 mg/mL. In fouling experiments, bovine serum albumin (BSA) was used as the protein model solution and activated sludge was used as the model biological sludge. Enzyme-activated membranes exhibited good filtration performances and protein rejection efficiencies were compared with raw CA membrane. Also the relative flux reduction (RFR) ratios of membranes were calculated as 97% and 88% for raw CA and enzyme-activated membranes (5 mg/mL savinase), respectively. The membrane activated with Savinase enzyme could be proposed as a surface treatment method before filtration to mitigate protein fouling. PMID:22218336

  10. α-Mangostin Reduced ER Stress-mediated Tumor Growth through Autophagy Activation

    PubMed Central

    Kim, Sung-Jin; Hong, Eun-Hye; Lee, Bo-Ra; Park, Moon-Ho; Kim, Ji-Won; Pyun, A-Rim; Kim, Yeon-Jeong; Chang, Sun-Young; Chin, Young-Won

    2012-01-01

    α-Mangostin is a xanthon derivative contained in the fruit hull of mangosteen (Garcinia mangostana L.), and the administration of α-Mangostin inhibited the growth of transplanted colon cancer, Her/CT26 cells which expressed Her-2/neu as tumor antigen. Although α-Mangostin was reported to have inhibitory activity against sarco/endoplasmic reticulum Ca2+ ATPase like thapsigargin, it showed different activity for autophagy regulation. In the current study, we found that α-Mangostin induced autophagy activation in mouse intestinal epithelial cells, as GFP-LC3 transgenic mice were orally administered with 20 mg/kg of α-Mangostin daily for three days. However, the activation of autophagy by α-Mangostin did not significantly increase OVA-specific T cell proliferation. As we assessed ER stress by using XBP-1 reporter system and phosphorylation of eIF2α, thapsigargin-induced ER stress was significantly reduced by α-Mangostin. However, coadministration of thapsigargin with α-Mangostin completely blocked the antitumor activity of α-Mangostin, suggesting ER stress with autophagy blockade accelerated tumor growth in mouse colon cancer model. Thus the antitumor activity of α-Mangostin can be ascribable to the autophagy activation rather than ER stress induction. PMID:23396851

  11. Actively compensation of low order aberrations by refractive shaping system for high power slab lasers

    NASA Astrophysics Data System (ADS)

    Xue, Zheng-wei; Guo, Ya-ding; Chen, Zhong-zheng; Li, Shuai; Xu, Yi-ting; Xu, Jian; Wang, Bao-shan; Gong, Ke-ling; Gao, Hong-wei; Bo, Yong; Peng, Qin-jun; Cui, Da-fu; Xu, Zu-yan

    2015-12-01

    We present a compact refractive shaping system for actively compensating low order aberrations of high power slab lasers. The shaping system includes three spherical lenses and two cylindrical lenses. Both theoretical and experimental investigations were performed to evaluate the compensation capability of the refractive shaping system. For a typical input beam with large low order aberrations of peak-to-valley (PV)=66.10λ and root-mean-square (RMS)=16.05λ, adjusting the distance between lenses, the wavefront aberrations are reduced to PV=0.48λ, RMS=0.10λ for the theoretical simulation and PV=0.50λ, RMS=0.11λ for the experimental result, respectively. It indicates that the main low order aberrations of defocus and 0° astigmatism can be significantly compensated by actively adjusting the distance between lenses and the experimental result agree well with the theoretical simulation.

  12. A Forecast of Reduced Solar Activity and Its Implications for NASA

    NASA Technical Reports Server (NTRS)

    Schatten, Kenneth; Franz, Heather

    2005-01-01

    The "Solar Dynamo" method of solar activity forecasting is reviewed. Known generically as a 'precursor" method, insofar as it uses observations which precede solar activity generation, this method now uses the Solar Dynamo Amplitude (SODA) Index to estimate future long-term solar activity. The peak amplitude of the next solar cycle (#24), is estimated at roughly 124 in terms of smoothed F10.7 Radio Flux and 74 in terms of the older, more traditional smoothed international or Zurich Sunspot number (Ri or Rz). These values are significantly smaller than the amplitudes of recent solar cycles. Levels of activity stay large for about four years near the peak in smoothed activity, which is estimated to occur near the 2012 timeflame. Confidence is added to the prediction of low activity by numerous examinations of the Sun s weakened polar field. Direct measurements are obtained by the Mount Wilson Solar Observatory and the Wilcox Solar Observatory. Further support is obtained by examining the Sun s polar faculae (bright features), the shape of coronal soft X-ray "holes," and the shape of the "source surface" - a calculated coronal feature which maps the large scale structure of the Sun s field. These features do not show the characteristics of well-formed polar coronal holes associated with typical solar minima. They show stunted polar field levels, which are thought to result in stunted levels of solar activity during solar cycle #24. The reduced levels of solar activity would have concomitant effects upon the space environment in which satellites orbit. In particular, the largest influences would affect orbit determination of satellites in LEO (Low Earth Orbit), based upon the altered thermospheric and exospheric densities. A decrease in solar activity would result in smaller satellite decay rates, as well as fewer large solar events that can destroy satellite electronic functions. Other effects of reduced solar activity upon the space environment include enhanced

  13. Antioxidant potential of green and black tea determined using the ferric reducing power (FRAP) assay.

    PubMed

    Langley-Evans, S C

    2000-05-01

    Tea is one of the most commonly consumed beverages in the world and is rich in polyphenolic compounds collectively known as the tea flavonoids. Tea flavonoids possess antioxidant properties in vitro and have been proposed as key protective dietary components, reducing risk of coronary heart disease and some cancers. The present study aimed to evaluate the possible effects of different preparation methods on the antioxidant properties of green and black tea. Antioxidant potentials of tea infusates were assessed using an assay based upon the reduction of ferric chloride linked to a chromophore. Green tea, black leaf tea and black tea in tea bags were infused with water at 90 degrees C for time periods ranging from 0.25 to 15 min. Green tea infusates possessed approximately 2.5-fold greater antioxidant capacity than both types of black tea infusates. Both green and black teas released significant levels of antioxidants into the hot water within 2 min of infusion. Preparation of teas across a range of temperatures between 20 and 90 degrees C revealed that although antioxidants were liberated from the leaves into the water in cooler infusions, increasing the temperature could increase antioxidant potential by 4 to 9.5-fold. Black tea prepared using tea bags had significantly lower antioxidant capacity than black leaf tea at temperatures between 20 and 70 degrees C, suggesting that tea bag materials may prevent some extraction of flavonoids into the tea solution. The addition of milk appeared to diminish the antioxidant potential of black tea preparations. This effect was greatest where whole cow's milk was used and appeared to be primarily related to the fat content of the added milk. These experiments have considered the effects of commonly used domestic methods of preparation on the in vitro antioxidant potential of tea. It is concluded that maximum antioxidant capacity and hence maximal health benefit may be derived from green tea or from black leaf tea prepared by

  14. Nitrogenase Activity Is Affected by Reduced Partial Pressures of N2 and NO3- 1.

    PubMed Central

    Blumenthal, J. M.; Russelle, M. P.; Vance, C. P.

    1997-01-01

    Optimal use of legumes in cropping systems requires a thorough understanding of the interaction between inorganic N nutrition and symbiotic N2 fixation. Our objective was to test the hypothesis that increased NO3- uptake by alfalfa (Medicago sativa L.) would compensate for lower N2 fixation caused by low partial pressure of N2. Root systems of hydroponically grown alfalfa at 2 mg L-1 NO3--N were exposed to (a) 80% N2, (b) 7% N2, (c) 2% N2, or (d) 0% N2. Exposure to reduced partial pressures of N2 reduced total nitrogenase activity (TNA, measured as H2 production in 20% O2 and 80% Ar) by 40% within less than 30 min, followed by a recovery period over the next 30 min to initial activity. Five hours after treatments began, the TNA of plants exposed to 7 and 2% N2 was substantially higher than pretreatment activities, whereas the TNA of plants exposed either to 0 or 80% N2 did not differ from pretreatment values. The decline in TNA due to NO3- exposure over 4 d was not affected by reduced partial pressure of N2. During the 1st h the proportion of electrons used for the reduction of N2 fell from 0.52 to 0.23 for plants exposed to 7% N2, and to 0.09 for plants exposed to 2% N2, and remained unchanged for the rest of the experiment. Although the hypothesis that alfalfa compensated with increased NO3- uptake for lower N2 fixation was not validated by our results, we unexpectedly demonstrated that the decline in TNA upon exposure to NO3- was independent of the N2-fixing efficiency (i.e. the amount of N2 reduced by nitrogenase) of the symbiosis. PMID:12223779

  15. Greater positive schizotypy relates to reduced N100 activity during rejection scenes.

    PubMed

    Premkumar, Preethi; Onwumere, Juliana; Wilson, Daniel; Sumich, Alexander; Castro, Antonio; Kumari, Veena; Kuipers, Elizabeth

    2014-08-01

    Social anxiety due to rejection sensitivity (RS) exacerbates psychosis-like experiences in the general population. While reduced dorsal anterior cingulate cortex (dACC) activity during social rejection in high schizotypy has suggested self-distancing from rejection, earlier stages of mental processing such as feature encoding could also contribute to psychosis-like experiences. This study aimed to determine the stage of mental processing of social rejection that relates to positive schizotypy. Forty-one healthy participants were assessed for schizotypy and RS. Event-related potential amplitudes (ERPs) were measured at frontal, temporal and parieto-occipital sites and their cortical sources (dACC, temporal pole and lingual gyrus) at early (N100) and late (P300 and late slow wave, LSW) timeframes during rejection, acceptance and neutral scenes. ERPs were compared between social interaction types. Correlations were performed between positive schizotypy (defined as the presence of perceptual aberrations, hallucinatory experiences and magical thinking), RS and ERPs during rejection. Amplitude was greater during rejection than acceptance or neutral conditions at the dACC-P300, parieto-occipital-P300, dACC-LSW and frontal-LSW. RS correlated positively with positive schizotypy. Reduced dACC N100 activity during rejection correlated with greater positive schizotypy and RS. Reduced dACC N100 activity and greater RS independently predicted positive schizotypy. An N100 deficit that indicates reduced feature encoding of rejection scenes increases with greater positive schizotypy and RS. Higher RS shows that a greater tendency to misattribute ambiguous social situations as rejecting also increases with positive schizotypy. These two processes, namely primary bottom-up sensory processing and secondary misattribution of rejection, combine to increase psychosis-like experiences. PMID:25010933

  16. Darapladib, a Lipoprotein-Associated Phospholipase A2 Inhibitor, Reduces Rho Kinase Activity in Atherosclerosis

    PubMed Central

    Xu, Dong-Ling; Liu, Xiao-Bo; Bi, Shao-jie; Zhao, Tong; Sui, Shu-Jian; Ji, Xiao-Ping

    2016-01-01

    Purpose Increased lipoprotein-associated phospholipase A2 (Lp-PLA2) activity and Rho kinase activity may be associated with atherosclerosis. The principal aim of this study was to examine whether darapladib (a selective Lp-PLA2 inhibitor) could reduce the elevated Lp-PLA2 and Rho kinase activity in atherosclerosis. Materials and Methods Studies were performed in male Sprague-Dawley rats. The atherosclerosis rats were prepared by feeding them with a high-cholesterol diet for 10 weeks. Low-dose darapladib (25 mg·kg-1·d-1) and high-dose darapladib (50 mg·kg-1·d-1) interventions were then administered over the course of 2 weeks. Results The serum levels of triglycerides, total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), high-sensitivity C-reactive protein (hs-CRP), and Lp-PLA2, significantly increased in atherosclerosis model groups, as did Rho kinase activity and cardiomyocyte apoptosis (p<0.05 vs. sham group), whereas nitric oxide (NO) production was reduced. Levels of TC, LDL-C, CRP, Lp-PLA2, and Rho kinase activity were respectively reduced in darapladib groups, whereas NO production was enhanced. When compared to the low-dose darapladib group, the reduction of the levels of TC, LDL-C, CRP, and Lp-PLA2 was more prominent in the high-dose darapladib group (p<0.05), and the increase of NO production was more prominent (p<0.05). Cardiomyocyte apoptosis of the high-dose darapladib group was also significantly reduced compared to the low-dose darapladib group (p<0.05). However, there was no significant difference in Rho kinase activity between the low-dose darapladib group and the high-dose darapladib group (p>0.05). Conclusion Darapladib, a Lp-PLA2 inhibitor, leads to cardiovascular protection that might be mediated by its inhibition of both Rho kinase and Lp-PLA2 in atherosclerosis. PMID:26847282

  17. Active shielding to reduce low frequency disturbances in direct current near biomagnetic measurements

    NASA Astrophysics Data System (ADS)

    Platzek, D.; Nowak, H.; Giessler, F.; Röther, J.; Eiselt, M.

    1999-05-01

    Measurements of dc near biomagnetic fields are disturbed by low frequency noise that is not reduced sufficiently by most of the magnetically shielded rooms or gradiometers. For this reason an active shielding system has been developed at the Biomagnetic Center of the University of Jena. This work describes the principle of the active shielding system and demonstrates its properties concerning the attenuation of disturbing fields, frequency range, and some applications in biomedical measurements. We achieved a reduction of external low frequency magnetic fields by more than 50 dB and an attenuation of the field gradient by about 25 dB. This active shielding enables measurements of near dc biomagnetic fields in investigations of periinfarct depolarizations after ischemic stroke and spreading depression in migraine patients.

  18. A transgenic apple callus showing reduced polyphenol oxidase activity and lower browning potential.

    PubMed

    Murata, M; Nishimura, M; Murai, N; Haruta, M; Homma, S; Itoh, Y

    2001-02-01

    Polyphenol oxidase (PPO) is responsible for enzymatic browning of apples. Apples lacking PPO activity might be useful not only for the food industry but also for studies of the metabolism of polyphenols and the function of PPO. Transgenic apple calli were prepared by using Agrobacterium tumefaciens carrying the kanamycin (KM) resistant gene and antisense PPO gene. Four KM-resistant callus lines were obtained from 356 leaf explants. Among these transgenic calli, three calli grew on the medium containing KM at the same rate as non-transgenic callus on the medium without KM. One callus line had an antisense PPO gene, in which the amount and activity of PPO were reduced to half the amount and activity in non-transgenic callus. The browning potential of this line, which was estimated by adding chlorogenic acid, was also half the browning potential of non-transgenic callus. PMID:11302173

  19. Carbamazepine-induced hemolytic and aplastic crises associated with reduced glutathione peroxidase activity of erythrocytes.

    PubMed

    Yamamoto, Masaki; Suzuki, Nobuhiro; Hatakeyama, Naoki; Kubo, Noriaki; Tachi, Nobutada; Kanno, Hitoshi; Fujii, Hisaichi; Tsutsumi, Hiroyuki

    2007-11-01

    Although pure red cell aplasia is a well-known side effect of carbamazepine treatment, intravascular hemolytic anemia is rare. We describe a 5-year-old boy who developed concurrent intravascular hemolytic anemia and erythroblastopenia, probably due to carbamazepine. Carbamazepine treatment was subsequently discontinued, and the patient was treated with red blood cell transfusions, haptoglobin, and methylprednisolone. His hematologic abnormalities were almost fully recovered within 2 weeks. Examination of the patient's and mother's erythrocyte enzyme activities revealed mildly decreased erythrocyte glutathione peroxidase (GSH-Px) activity. We speculate that patients with reduced GSH-Px activity are at a high risk of developing carbamazepine-induced hemolytic crisis and/or aplastic crisis. PMID:18055338

  20. Compilation of Trade Studies for the Constellation Program Extravehicular Activity Spacesuit Power System

    NASA Technical Reports Server (NTRS)

    Fincannon, James

    2009-01-01

    This compilation of trade studies performed from 2005 to 2006 addressed a number of power system design issues for the Constellation Program Extravehicular Activity Spacesuit. Spacesuits were required for spacewalks and in-space activities as well as lunar and Mars surface operations. The trades documented here considered whether solar power was feasible for spacesuits, whether spacesuit power generation should be a distributed or a centralized function, whether self-powered in-space spacesuits were better than umbilically powered ones, and whether the suit power system should be recharged in place or replaced.

  1. A high gas fraction, reduced power, syngas bioprocessing method demonstrated with a Clostridium ljungdahlii OTA1 paper biocomposite.

    PubMed

    Schulte, Mark J; Wiltgen, Jeff; Ritter, John; Mooney, Charles B; Flickinger, Michael C

    2016-09-01

    We propose a novel approach to continuous bioprocessing of gases. A miniaturized, coated-paper strip, high gas fraction, biocomposite absorber has been developed using slowly shaken horizontal anaerobic tubes. Concentrated Clostridium ljungdahlii OTA1 was used as a model system. These gas absorbers demonstrate elevated CO mass transfer with low power input, reduced liquid requirements, elevated substrate consumption, and increased product secretion compared to shaken suspended cells. Concentrated OTA1 cell paste was coated by extrusion onto chromatography paper. The immobilized system shows high, constant reactivity immediately upon rehydration. Cell adhesion was by adsorption to the cellulose fibers; visualized by SEM. The C. ljungdahlii OTA1 coated paper mounted above the liquid level absorbs CO and H2 from a model syngas secreting acetate with minimal ethanol. At 100 rpm shaking speed (7.7 Wm(-3) ) the optimal cell loading is 6.5 gDCW m(-2) to maintain high CO absorbing reactivity without the cells coming off of the paper into the liquid phase. Reducing the medium volume from 10 mL to 4 mL (15% of tube volume) did not decrease CO reactivity. The reduced liquid volume increased secreted product concentration by 80%. The specific CO consumption by paper biocomposites was higher at all shaking frequencies <100 rpm than suspended cells under identical incubation conditions. At 25 rpm the biocomposite outperforms suspended cells for CO absorption by 2.5-fold, with an estimated power reduction of 97% over the power input at 100 rpm. The estimated minimum kL a for miniaturized biocomposite gas-absorbers is ∼100 h(-1) , 10 to 10(4) less power input than other syngas fermentation systems reported in the literature at similar kL a. Specific consumption rates in a biocomposite were ∼14 mmol gDCW-1 h(-1) . This work intensified CO absorption and reactivity by 14-fold to 94 mmol CO m(-2) h(-1) over previous C. ljungdahlii OTA1 work by our group

  2. Potential association of reduced cholinesterase activity with Trypanosoma evansi pathogenesis in buffaloes.

    PubMed

    Singh, Shanker K; Singh, Vivek K; Yadav, Brajesh K; Nakade, Udayraj P; Kumari, Priyambada; Srivastava, Mukesh K; Sharma, Abhishek; Choudhary, Soumen; Swain, Dilip; Garg, Satish K

    2016-07-30

    The present study aimed to investigate the association of cholinesterase activity with trypanosomosis in buffaloes. Thirty-three clinical cases of trypanosomosis in water buffaloes, found positive for trypomastigotes of T. evansi on blood smear examination, were divided into two groups based on clinical manifestations. Twenty diseased buffaloes revealing only common clinical signs were allocated to Group I, while the remaining 13 buffaloes showing common clinical manifestations along with neurological disturbances were allocated to Group II. Twelve clinically healthy buffaloes, free from any haemoprotozoa infection, were kept as healthy control (Group III). Blood samples were collected from buffaloes of all three groups to determine serum cholinesterase activity. Compared to buffaloes of healthy control group, cholinesterase activity in T. evansi-infected buffaloes of Group I and II was significantly (P<0.001) lower. However, no significant difference was observed in cholinesterase activity between the T. evansi-infected buffaloes exhibiting neurological disorders and no neurological disorders. Summing up, reduced cholinesterase activity seems to be associated with the pathogenesis of natural T. evansi infection and its clinical manifestations in buffaloes possibly by evading immune response. Further studies are warranted on association of cholinesterase activity in T. evansi-infected buffaloes with neurological disorders. PMID:27369572

  3. Adipose Mesenchymal Stromal Cells Isolated From Type 2 Diabetic Patients Display Reduced Fibrinolytic Activity

    PubMed Central

    Acosta, Lourdes; Hmadcha, Abdelkrim; Escacena, Natalia; Pérez-Camacho, Inmaculada; de la Cuesta, Antonio; Ruiz-Salmeron, Rafael; Gauthier, Benoit R.; Soria, Bernat

    2013-01-01

    Stem cells have been successfully used for the treatment of critical limb ischemia (CLI). We conducted a clinical trial to determine the feasibility of using autologous adipose-derived mesenchymal stromal cells (AdMSCs) for the treatment of CLI. Unexpectedly, two diabetic patients developed peripheral microthrombosis. This adverse effect, which contrasts with the reported antithrombotic properties of MSCs, may stem from the diabetic environment that alters the fibrinolytic activity of AdMSCs, thereby increasing the probability of developing thrombosis. Here, we confirm this premise by demonstrating that diabetic AdMSCs cultured in the presence of blood sera expressed and released higher levels of plasminogen activator inhibitor type 1, reduced levels of tissue plasminogen activator, and lower d-dimer formation compared with nondiabetic AdMSCs. Thus, to establish an appropriate cell therapy for diabetic patients, we recommend including new preclinical safety tests, such as the d-dimer and/or the tissue plasminogen activator-to-plasminogen activator inhibitor type 1 ratio tests, to assess fibrinolytic activity of cells before implantation. PMID:24043757

  4. Simulated microgravity alters multipotential differentiation of rat mesenchymal stem cells in association with reduced telomerase activity

    NASA Astrophysics Data System (ADS)

    Sun, Lianwen; Gan, Bo; Fan, Yubo; Xie, Tian; Hu, Qinghua; Zhuang, Fengyuan

    Microgravity is one of the most important characteristics in space flight. Exposure to microgravity results in extensive physiological changes in humans. Bone loss is one of the changes with serious consequences; however, the mechanism retains unclear. As the origin of osteoprogenitors, mesenchymal stem cells (MSCs) may play an important role in it. After cultured under simulated microgravity (in a rotary cell culture system, RCCS), MSCs were stained using oil red O to identify adipocytes. The mRNA level of bone morphogenetic protein (BMP)-2 and peroxisome proliferators-activated receptor (PPAR) γ2 was determined by RT-PCR. Otherwise, MSCs were induced to osteogenic differentiation after microgravity culture, and then the activity of alkaline phosphatase (ALP) was determined by PNPP and the content of osteocalcin (OC) by ELISA. Furthermore, the telomerase activity in MSCs was measured by TRAP. The results showed that simulated microgravity inhibited osteoblastic differentiation and induced adipogenic differentiation accompanied by the change of gene expression of BMP-2 and PPARγ2 in MSCs. Meanwhile, the telomerase activity decreased significantly in MSCs under simulated microgravity. The reduced bone formation in space flight may partly be due to the altered potential differentiation of MSCs associated with telomerase activity which plays a key role in regulating the lifespan of cell proliferation and differentiation. Therefore, telomerase activation/replacement may act as a potential countermeasure for microgravity-induced bone loss.

  5. Characterization of Triosephosphate Isomerase Mutants with Reduced Enzyme Activity in Mus Musculus

    PubMed Central

    Merkle, S.; Pretsch, W.

    1989-01-01

    Four heterozygous triosephosphate isomerase (TPI) mutants with approximately 50% reduced activity in blood compared to wild type were detected in offspring of 1-ethyl-1-nitrosourea treated male mice. Breeding experiments displayed an autosomal, dominant mode of inheritance for the mutations. All mutations were found to be homozygous lethal at an early postimplantation stage of embryonic development, probably due to a total lack of TPI activity and consequently to the inability to utilize glucose as a source of metabolic energy. Although activity alteration was also found in liver, lung, kidney, spleen, heart, brain and muscle the TPI deficiency in heterozygotes has no influence on the following physiological traits: hematological parameters, plasma glucose, glucose consumption of blood cells, body weight and organo-somatic indices of liver, spleen, heart, kidney and lung. Biochemical investigations of TPI in the four mutant lines indicated no difference of physicochemical properties compared to the wild type. Results from immunoinactivation assays indicate that the decrease of enzyme activity corresponds to a decrease in the level of an immunologically active moiety. It is suggested that the mutations have affected the Tpi-1 structural locus and resulted in alleles which produce no detectable enzyme activity and no immunologically cross-reacting material. The study furthermore suggests one functional TPI gene per haploid genome in the erythrocyte and seven other tested organs of the mouse. PMID:2693209

  6. Reducing, by pulse width modulation, the curing temperature of a prototype high-power LED light curing unit.

    PubMed

    Huang, Ta-Ko; Hung, Chun-Cheng; Tsai, Chi-Cheng

    2006-06-01

    Third-generation LEDs have high irradiance and efficiency, but the associated temperature rise is potentially hazardous to the pulp of teeth. We evaluated, during composite polymerization, the irradiance and temperature rise of a prototype high-power LED light curing unit (LCU) with optimal pulse width modulation (PWM), and then compared the results with four off-the-shelf high-power LCUs. A cavity was prepared in a tooth, and a composite resin layer was applied and cured. For each LCU, the irradiance and temperature changes at the pulp-dentin junction were measured. Microhardness (Vickers hardness) of cured composite samples was measured for each LCU. Our prototype had a final temperature of 36.4 +/- 1.3 degrees C and irradiance of 1,182 +/- 1 mW/cm2. The unit with the highest temperature had a temperature of 48.7 +/- 1.2 degrees C and an irradiance of 1,194 +/- 1 mW/cm2. Based on the results of the present study, it was shown that PWM technology reduced the curing temperature while retaining the polymerization effectiveness of a high-power LED LCU. PMID:16916235

  7. Hydrogen sulfide reduces serum triglyceride by activating liver autophagy via the AMPK-mTOR pathway.

    PubMed

    Sun, Li; Zhang, Song; Yu, Chengyuan; Pan, Zhenwei; Liu, Yang; Zhao, Jing; Wang, Xiaoyu; Yun, Fengxiang; Zhao, Hongwei; Yan, Sen; Yuan, Yue; Wang, Dingyu; Ding, Xue; Liu, Guangzhong; Li, Wenpeng; Zhao, Xuezhu; Liu, Zhaorui; Li, Yue

    2015-12-01

    Autophagy plays an important role in liver triglyceride (TG) metabolism. Inhibition of autophagy could reduce the clearance of TG in the liver. Hydrogen sulfide (H2S) is a potent stimulator of autophagic flux. Recent studies showed H2S is protective against hypertriglyceridemia (HTG) and noalcoholic fatty liver disease (NAFLD), while the mechanism remains to be explored. Here, we tested the hypothesis that H2S reduces serum TG level and ameliorates NAFLD by stimulating liver autophagic flux by the AMPK-mTOR pathway. The level of serum H2S in patients with HTG was lower than that of control subjects. Sodium hydrosulfide (NaHS, H2S donor) markedly reduced serum TG levels of male C57BL/6 mice fed a high-fat diet (HFD), which was abolished by coadministration of chloroquine (CQ), an inhibitor of autophagic flux. In HFD mice, administration of NaSH increased the LC3BII-to-LC3BI ratio and decreased the p62 protein level. Meanwhile, NaSH increased the phosphorylation of AMPK and thus reduced the phosphorylation of mTOR in a Western blot study. In cultured LO2 cells, high-fat treatment reduced the ratio of LC3BII to LC3BI and the phosphorylation of AMPK, which were reversed by the coadministration of NaSH. Knockdown of AMPK by siRNA in LO2 cells blocked the autophagic enhancing effects of NaSH. The same qualitative effect was observed in AMPKα2(-/-) mice. These results for the first time demonstrated that H2S could reduce serum TG level and ameliorate NAFLD by activating liver autophagy via the AMPK-mTOR pathway. PMID:26442880

  8. Modeling of power and energy transduction of embedded piezoelectric wafer active sensors for structural health monitoring

    NASA Astrophysics Data System (ADS)

    Lin, Bin; Giurgiutiu, Victor

    2010-04-01

    This paper presents a systematic investigation of power and energy transduction in piezoelectric wafer active sensors (PWAS) for structural health monitoring (SHM). After a literature review of the state of the art, the paper develops a simplified pitch-catch model of power and energy transduction of PWAS attached to structure. The model assumptions include: (a) 1-D axial and flexural wave propagation; (b) ideal bonding (pin-force) connection between PWAS and structure; (c) ideal excitation source at the transmitter PWAS and fully-resistive external load at the receiver PWAS. Frequency response functions are developed for voltage, current, complex power, active power, etc. First, we examined PWAS transmitter and determined the active power, reactive power, power rating of electrical requirement under harmonic voltage excitation. It was found that the reactive power is dominant and defines the power requirement for power supply / amplifier for PWAS applications. The electrical and mechanical power analysis at the PWAS structure interface indicates all the active electrical power provides the mechanical power at the interface. This provides the power and energy for the axial and flexural waves power and energy that propagate into the structure. The sum of forward and backward wave power equals the mechanical power PWAS applied to the structure. The parametric study of PWAS transmitter size shows the proper size and excitation frequency selection based on the tuning effects. Second, we studied the PWAS receiver structural interface acoustic and electrical energy transduction. The parametric study of receiver size, receiver impedance and external electrical load gives the PWAS design guideline for PWAS sensing and power harvesting applications. Finally we considered the power flow for a complete pitch-catch setup. In pitch-catch mode, the power flows from electrical source into piezoelectric power at the transmitter; the piezoelectric conduction converts the electrical

  9. Hyaluronan modulates TRPV1 channel opening, reducing peripheral nociceptor activity and pain

    PubMed Central

    Caires, Rebeca; Luis, Enoch; Taberner, Francisco J.; Fernandez-Ballester, Gregorio; Ferrer-Montiel, Antonio; Balazs, Endre A.; Gomis, Ana; Belmonte, Carlos; de la Peña, Elvira

    2015-01-01

    Hyaluronan (HA) is present in the extracellular matrix of all body tissues, including synovial fluid in joints, in which it behaves as a filter that buffers transmission of mechanical forces to nociceptor nerve endings thereby reducing pain. Using recombinant systems, mouse-cultured dorsal root ganglia (DRG) neurons and in vivo experiments, we found that HA also modulates polymodal transient receptor potential vanilloid subtype 1 (TRPV1) channels. HA diminishes heat, pH and capsaicin (CAP) responses, thus reducing the opening probability of the channel by stabilizing its closed state. Accordingly, in DRG neurons, HA decreases TRPV1-mediated impulse firing and channel sensitization by bradykinin. Moreover, subcutaneous HA injection in mice reduces heat and capsaicin nocifensive responses, whereas the intra-articular injection of HA in rats decreases capsaicin joint nociceptor fibres discharge. Collectively, these results indicate that extracellular HA reduces the excitability of the ubiquitous TRPV1 channel, thereby lowering impulse activity in the peripheral nociceptor endings underlying pain. PMID:26311398

  10. Dopamine D2/3 receptor antagonism reduces activity-based anorexia.

    PubMed

    Klenotich, S J; Ho, E V; McMurray, M S; Server, C H; Dulawa, S C

    2015-01-01

    Anorexia nervosa (AN) is an eating disorder characterized by severe hypophagia and weight loss, and an intense fear of weight gain. Activity-based anorexia (ABA) refers to the weight loss, hypophagia and paradoxical hyperactivity that develops in rodents exposed to running wheels and restricted food access, and provides a model for aspects of AN. The atypical antipsychotic olanzapine was recently shown to reduce both AN symptoms and ABA. We examined which component of the complex pharmacological profile of olanzapine reduces ABA. Mice received 5-HT(2A/2C), 5-HT3, dopamine D1-like, D2, D3 or D2/3 antagonist treatment, and were assessed for food intake, body weight, wheel running and survival in ABA. D2/3 receptor antagonists eticlopride and amisulpride reduced weight loss and hypophagia, and increased survival during ABA. Furthermore, amisulpride produced larger reductions in weight loss and hypophagia than olanzapine. Treatment with either D3 receptor antagonist SB277011A or D2 receptor antagonist L-741,626 also increased survival. All the other treatments either had no effect or worsened ABA. Overall, selective antagonism of D2 and/or D3 receptors robustly reduces ABA. Studies investigating the mechanisms by which D2 and/or D3 receptors regulate ABA, and the efficacy for D2/3 and/or D3 antagonists to treat AN, are warranted. PMID:26241351

  11. Dopamine D2/3 receptor antagonism reduces activity-based anorexia

    PubMed Central

    Klenotich, S J; Ho, E V; McMurray, M S; Server, C H; Dulawa, S C

    2015-01-01

    Anorexia nervosa (AN) is an eating disorder characterized by severe hypophagia and weight loss, and an intense fear of weight gain. Activity-based anorexia (ABA) refers to the weight loss, hypophagia and paradoxical hyperactivity that develops in rodents exposed to running wheels and restricted food access, and provides a model for aspects of AN. The atypical antipsychotic olanzapine was recently shown to reduce both AN symptoms and ABA. We examined which component of the complex pharmacological profile of olanzapine reduces ABA. Mice received 5-HT2A/2C, 5-HT3, dopamine D1-like, D2, D3 or D2/3 antagonist treatment, and were assessed for food intake, body weight, wheel running and survival in ABA. D2/3 receptor antagonists eticlopride and amisulpride reduced weight loss and hypophagia, and increased survival during ABA. Furthermore, amisulpride produced larger reductions in weight loss and hypophagia than olanzapine. Treatment with either D3 receptor antagonist SB277011A or D2 receptor antagonist L-741,626 also increased survival. All the other treatments either had no effect or worsened ABA. Overall, selective antagonism of D2 and/or D3 receptors robustly reduces ABA. Studies investigating the mechanisms by which D2 and/or D3 receptors regulate ABA, and the efficacy for D2/3 and/or D3 antagonists to treat AN, are warranted. PMID:26241351

  12. Bacteriophages of wastewater foaming-associated filamentous Gordonia reduce host levels in raw activated sludge

    PubMed Central

    Liu, Mei; Gill, Jason J.; Young, Ry; Summer, Elizabeth J.

    2015-01-01

    Filamentous bacteria are a normal and necessary component of the activated sludge wastewater treatment process, but the overgrowth of filamentous bacteria results in foaming and bulking associated disruptions. Bacteriophages, or phages, were investigated for their potential to reduce the titer of foaming bacteria in a mixed-microbial activated sludge matrix. Foaming-associated filamentous bacteria were isolated from activated sludge of a commercial wastewater treatment plan and identified as Gordonia species by 16S rDNA sequencing. Four representative phages were isolated that target G. malaquae and two un-named Gordonia species isolates. Electron microscopy revealed the phages to be siphophages with long tails. Three of the phages - GordTnk2, Gmala1, and GordDuk1 - had very similar ~76 kb genomes, with >93% DNA identity. These genomes shared limited synteny with Rhodococcus equi phage ReqiDocB7 and Gordonia phage GTE7. In contrast, the genome of phage Gsput1 was smaller (43 kb) and was not similar enough to any known phage to be placed within an established phage type. Application of these four phages at MOIs of 5–15 significantly reduced Gordonia host levels in a wastewater sludge model by approximately 10-fold as compared to non-phage treated reactors. Phage control was observed for nine days after treatment. PMID:26349678

  13. Quinone-mediated microbial synthesis of reduced graphene oxide with peroxidase-like activity.

    PubMed

    Liu, Guangfei; Zhang, Xin; Zhou, Jiti; Wang, Aijie; Wang, Jing; Jin, Ruofei; Lv, Hong

    2013-12-01

    The effects of different quinones on graphene oxide (GO) reduction by Shewanella oneidensis MR-1 and the peroxidase activity of the resultant reduced graphene oxide (QRGO) were studied. The presence of 100 μM anthraquinone-2-sulfonate (AQS), anthraquinone-2,6-disulfonate and 5-hydroxy-1,4-naphthoquinone could lead to 1.6-2.8-fold increase in GO reduction rate, whereas anthraquinone-2-carboxylate slowed down the reduction. The stimulating effects of AQS increased with the increase of its concentration (10-100 μM). The mediated effects were proved by direct GO reduction by microbially reduced AQS. The mediated reduction of GO to QRGO was characterized by UV-vis, XRD, FTIR, Raman spectra, XPS, TEM and AFM, respectively. The as-prepared QRGO possessed peroxidase-like activity, which could catalyze the oxidation of 3,3'5,5'-tetramethylbenzidine by H2O2, and followed Michealis-Menten kinetics. A colorimetric sensor for quantitative determination of glucose based on the peroxidase activity of QRGO was developed over a range of 1-120 μM with a detection limit of 1 μM. PMID:24140856

  14. Micro-structuring of polycarbonate-urethane surfaces in order to reduce platelet activation and adhesion.

    PubMed

    Clauser, Johanna; Gester, Kathrin; Roggenkamp, Jan; Mager, Ilona; Maas, Judith; Jansen, Sebastian V; Steinseifer, Ulrich

    2014-01-01

    In the development of new hemocompatible biomaterials, surface modification appears to be a suitable method in order to reduce the thrombogenetic potential of such materials. In this study, polycarbonate-urethane (PCU) tubes with different surface microstructures to be used for aortic heart valve models were investigated with regard to the thrombogenicity. The surface structures were produced by using a centrifugal casting process for manufacturing PCU tubes with defined casting mold surfaces which are conferred to the PCU surface during the process. Tubes with different structures defined by altering groove widths were cut into films and investigated under dynamic flow conditions in contact with porcine blood. The analysis was carried out by laser scanning microscopy which allowed for counting various morphological types of platelets with regard to the grade of activation. The comparison between plain and shaped PCU samples showed that the surface topography led to a decline of the activation of the coagulation cascade and thus to the reduction of the fibrin synthesis. Comparing different types of structures revealed that smooth structures with a small groove width (d ~ 3 μm) showed less platelet activation as well as less adhesion in contrast to a distinct wave structure (d ~ 90 μm). These results prove surface modification of polymer biomaterials to be a suitable method for reducing thrombogenicity and hence give reason for further alterations and improvements. PMID:24484511

  15. Mex3c mutation reduces adiposity partially through increasing physical activity.

    PubMed

    Han, Changjie; Jiao, Yan; Zhao, Qingguo; Lu, Baisong

    2014-06-01

    MEX3C is an RNA-binding protein with unknown physiological function. We have recently reported that a Mex3c mutation in mice causes growth retardation and reduced adiposity, but how adiposity is reduced remains unclear. Herein, we show that homozygous Mex3c gene trap mice have increased physical activity. The Mex3c mutation consistently conferred full protection from diet-induced obesity, hyperglycemia, insulin resistance, hyperlipidemia, and hepatic steatosis. In ob/ob mice with leptin deficiency, the Mex3c mutation also increased physical activity and improved glucose and lipid profiles. Expressing cre in the neurons of Mex3c gene trap mice, an attempt to partially restoring neuronal Mex3c expression, significantly increased white adipose tissue deposition, but had no effects on body length. Our data suggest that one way in which Mex3c regulates adiposity is through controlling physical activity, and that neuronal Mex3c expression could play an important role in this process. PMID:24741071

  16. Kank2 activates talin, reduces force transduction across integrins and induces central adhesion formation.

    PubMed

    Sun, Zhiqi; Tseng, Hui-Yuan; Tan, Steven; Senger, Fabrice; Kurzawa, Laetitia; Dedden, Dirk; Mizuno, Naoko; Wasik, Anita A; Thery, Manuel; Dunn, Alexander R; Fässler, Reinhard

    2016-09-01

    Integrin-based adhesions play critical roles in cell migration. Talin activates integrins and flexibly connects integrins to the actomyosin cytoskeleton, thereby serving as a 'molecular clutch' that transmits forces to the extracellular matrix to drive cell migration. Here we identify the evolutionarily conserved Kank protein family as novel components of focal adhesions (FAs). Kank proteins accumulate at the lateral border of FAs, which we term the FA belt, and in central sliding adhesions, where they directly bind the talin rod domain through the Kank amino-terminal (KN) motif and induce talin and integrin activation. In addition, Kank proteins diminish the talin-actomyosin linkage, which curbs force transmission across integrins, leading to reduced integrin-ligand bond strength, slippage between integrin and ligand, central adhesion formation and sliding, and reduced cell migration speed. Our data identify Kank proteins as talin activators that decrease the grip between the integrin-talin complex and actomyosin to regulate cell migration velocity. PMID:27548916

  17. Reduced expression of PNUTS leads to activation of Rb-phosphatase and caspase-mediated apoptosis.

    PubMed

    De Leon, Gabriel; Sherry, Tara C; Krucher, Nancy A

    2008-06-01

    There is abundant evidence that Retinoblastoma (Rb) activity is important in the control of cell proliferation and apoptosis. Reversible phosphorylation of the Rb protein that is carried out by cyclin dependent kinases and Protein phosphatase 1 (PP1) regulates its functions. A PP1 interacting protein, PNUTS (Phosphatase Nuclear Targeting Subunit) is proposed to be a regulator of Rb phosphorylation. In this study, PNUTS knockdown in MCF7, SKA and HCT116 cancer cells causes a reduction in viability due to increased apoptosis. However, normal cells (MCF10A breast and CCD-18Co colon) do not exhibit reduced viability when PNUTS expression is diminished. PNUTS knockdown has no effect in Rb-null Saos-2 cells. However, when Rb is stably expressed in Saos-2 cells, PNUTS knockdown reduces cell number. Knockdown of PNUTS in p53-/- HCT116 cells indicates that p53 is dispensable for the induction of apoptosis. Loss of PNUTS expression results in increased Rb-phosphatase activity and Rb dephosphorylation. E2F1 dissociates from Rb in cells depleted of PNUTS and the resulting apoptosis is dependent on caspase-8. These results indicate that Rb phosphorylation state can be manipulated by targeting Rb phosphatase activity and suggest that PNUTS may be a potential target for therapeutic pro-apoptotic strategies. PMID:18360108

  18. Nitroxyl (HNO) reduces endothelial and monocyte activation and promotes M2 macrophage polarization.

    PubMed

    Andrews, Karen L; Sampson, Amanda K; Irvine, Jennifer C; Shihata, Waled A; Michell, Danielle L; Lumsden, Natalie G; Lim, Chloe; Huet, Olivier; Drummond, Grant R; Kemp-Harper, Barbara K; Chin-Dusting, Jaye P F

    2016-09-01

    Nitroxyl anion (HNO) donors are currently being assessed for their therapeutic utility in several cardiovascular disorders including heart failure. Here, we examine their effect on factors that precede atherosclerosis including endothelial cell and monocyte activation, leucocyte adhesion to the endothelium and macrophage polarization. Similar to the NO donor glyceryl trinitrate (GTN), the HNO donors Angeli's salt (AS) and isopropylamine NONOate (IPA/NO) decreased leucocyte adhesion to activated human umbilical vein endothelial cells (HUVECs) and mouse isolated aorta. This reduction in adhesion was accompanied by a reduction in intercellular adhesion molecule-1 (ICAM-1) and the cytokines monocyte chemoattractant protein 1 (MCP-1) and interleukin 6 (IL-6) which was inhibitor of nuclear factor κB (NFκB) α (IκBα)- and subsequently NFκB-dependent. Intriguingly, the effects of AS on leucocyte adhesion, like those on vasodilation, were found to not be susceptible to pharmacological tolerance, unlike those observed with GTN. As well, HNO reduces monocyte activation and promotes polarization of M2 macrophages. Taken together, our data demonstrate that HNO donors can reduce factors that are associated with and which precede atherosclerosis and may thus be useful therapeutically. Furthermore, since the effects of the HNO donors were not subject to tolerance, this confers an additional advantage over NO donors. PMID:27231254

  19. Activated sludge as substrate for sulfate-reducing bacteria in acid mine drainage treatment

    SciTech Connect

    Al-Ani, W.A.G.; Henry, J.G.; Prasad, D.

    1996-11-01

    Acid mine drainage (AMD), characterized by high concentrations of sulfates and heavy metals and low pH, presents a potential hazard to the environment.Several treatment processes (chemical precipitation, ion exchange, reverse osmosis, electrodialysis and electrolytic recovery) are available, but these are often too expensive. Biological treatment of AMD, mediated by sulfate-reducing bacteria (SRB), seems promising. The objective of this study was to use activated sludge as a carbon source for the SRB and determine the most effective COD/sulfate ratio and hydraulic retention time (HRT) for reducing sulfate. Such information would be useful for the application of the proposed two-stage system to AMD treatment. Since the aim of this study was to obtain sulfate reduction and to avoid methane production, it was decided to operate the digesters initially at low COD/SO{sub 4}{sup 2{minus}} ratios of 1.0, 1.5, and 2.0.

  20. Microstructure and Mechanical Properties of a Nitride-Strengthened Reduced Activation Ferritic/Martensitic Steel

    NASA Astrophysics Data System (ADS)

    Zhou, Qiangguo; Zhang, Wenfeng; Yan, Wei; Wang, Wei; Sha, Wei; Shan, Yiyin; Yang, Ke

    2012-12-01

    Nitride-strengthened reduced activation ferritic/martensitic (RAFM) steels are developed taking advantage of the high thermal stability of nitrides. In the current study, the microstructure and mechanical properties of a nitride-strengthened RAFM steel with improved composition were investigated. Fully martensitic microstructure with fine nitrides dispersion was achieved in the steel. In all, 1.4 pct Mn is sufficient to suppress delta ferrite and assure the steel of the full martensitic microstructure. Compared to Eurofer97, the steel showed similar strength at room temperature but higher strength at 873 K (600 °C). The steel exhibited very high impact toughness and a low ductile-to-brittle transition temperature (DBTT) of 243 K (-30 °C), which could be further reduced by purification.

  1. Reduced lymphocyte activation in space - Role of cell-substratum interactions

    NASA Technical Reports Server (NTRS)

    Gmuender, F. K.; Kiess, M.; Lee, J.; Cogoli, A.; Sonnenfeld, G.

    1992-01-01

    The effect of substratum adhesiveness on lymphocyte responsiveness was investigated by reducing and blocking cell adhesion with poly-HEMA in a simple on ground system. Cells grown on medium thick and thick poly-HEMA films were rounded in shape and displayed no signs of spreading. By contrast, on tissue culture plastic and very thin poly-HEMA films, they showed clear signs of spreading. The mitogenic response of lymphocytes grown on thick poly-HEMA films was reduced by up to 68 percent of the control (tissue culture plastic). Interferon gamma production was virtually nil when the cells were grown on the least adhesive substratum. These results show that activated lymphocytes need to anchor and spread prior to achieving an optimal proliferation response. It is concluded that decreased lymphocyte adhesion could contribute to the depressed in vitro lymphocyte responsiveness found in the microgravity conditions of space flight.

  2. Reduced lymphocyte activation in space: Role of cell-substratum interactions

    NASA Technical Reports Server (NTRS)

    Gmuender, Felix K.; Kiess, M.; Sonnenfeld, Gerald; Lee, J.; Cogoli, Augusto

    1990-01-01

    The effect of substratum adhesiveness on lymphocyte responsiveness was investigated by reducing and blocking cell adhesion with poly-HEMA (poly (2-Hydroxyethyl Methacrylate)) in a simple on ground system. Cells grown on medium thick and thick poly-HEMA films were rounded in shape and displayed no signs of spreading. By contrast, on tissue culture plastic and very thin poly-HEMA films, they showed clear signs of spreading. The mitogenic response of lymphocytes grown on thick poly-HEMA films was reduced by up to 68 percent of the control (tissue culture plastic). Interferon gamma production was virtually nil when the cells were grown on the least adhesive substratum. These results show that activated lymphocytes need to anchor and spread prior to achieving an optimal proliferation response. It is concluded that decreased lymphocyte adhesion could contribute to the depressed in vitro lymphocyte responsiveness found in the microgravity conditions of space flight.

  3. The Associative Memory Deficit in Aging Is Related to Reduced Selectivity of Brain Activity during Encoding.

    PubMed

    Saverino, Cristina; Fatima, Zainab; Sarraf, Saman; Oder, Anita; Strother, Stephen C; Grady, Cheryl L

    2016-09-01

    Human aging is characterized by reductions in the ability to remember associations between items, despite intact memory for single items. Older adults also show less selectivity in task-related brain activity, such that patterns of activation become less distinct across multiple experimental tasks. This reduced selectivity or dedifferentiation has been found for episodic memory, which is often reduced in older adults, but not for semantic memory, which is maintained with age. We used fMRI to investigate whether there is a specific reduction in selectivity of brain activity during associative encoding in older adults, but not during item encoding, and whether this reduction predicts associative memory performance. Healthy young and older adults were scanned while performing an incidental encoding task for pictures of objects and houses under item or associative instructions. An old/new recognition test was administered outside the scanner. We used agnostic canonical variates analysis and split-half resampling to detect whole-brain patterns of activation that predicted item versus associative encoding for stimuli that were later correctly recognized. Older adults had poorer memory for associations than did younger adults, whereas item memory was comparable across groups. Associative encoding trials, but not item encoding trials, were predicted less successfully in older compared with young adults, indicating less distinct patterns of associative-related activity in the older group. Importantly, higher probability of predicting associative encoding trials was related to better associative memory after accounting for age and performance on a battery of neuropsychological tests. These results provide evidence that neural distinctiveness at encoding supports associative memory and that a specific reduction of selectivity in neural recruitment underlies age differences in associative memory. PMID:27082043

  4. Instantaneous Active and Nonactive Power Control of Distributed Energy Resources with Current Limiter

    SciTech Connect

    Xu, Yan; Li, Huijuan; Rizy, D Tom; Li, Fangxing; Kueck, John D

    2010-01-01

    Abstract -- Distributed energy resources (DER) with a power electronics inverter interface can provide both active power and nonactive power simultaneously and independently. A decoupled control algorithm of active power and nonactive power is developed based on the instantaneous active power and nonactive power theory. A current limiter is combined to the control algorithm, and it ensures that the inverter is not overloaded. During the normal system operation, the active power has higher priority over the nonactive power so that the energy from a DER can be fully transferred to the grid. Within the inverter s capability, nonactive power is provided to the grid as required. With this control algorithm, the inverter s capabilities are taken full advantage at all times, both in terms of functionality as well as making use of its full KVA rating. Through the algorithm, the inverter s active power and nonactive power are controlled directly, simultaneously, and independently. Several experimental results fully demonstrate the validity and effectiveness of this new control algorithm. As evidenced by the fast dynamic response that results, a DER system with the control algorithm can provide full services to the grid in both steady state and during transient events.

  5. Adapting sustainable low-carbon techologies to reduce carbon dioxide emissions from coal-fired power plants in China

    NASA Astrophysics Data System (ADS)

    Kuo, Peter Shyr-Jye

    1997-09-01

    The scientific community is deeply concerned about the effect of greenhouse-gases (GHGs) on global climate change. A major climate shift can result in tragic destruction to our world. Carbon dioxide (COsb2) emissions from coal-fired power plants are major anthropogenic sources that contribute to potential global warming. The People's Republic of China, with its rapidly growing economy and heavy dependence on coal-fired power plants for electricity, faces increasingly serious environmental challenges. This research project seeks to develop viable methodologies for reducing the potential global warming effects and serious air pollution arising from excessive coal burning. China serves as a case study for this research project. Major resolution strategies are developed through intensive literature reviews to identify sustainable technologies that can minimize adverse environmental impacts while meeting China's economic needs. The research thereby contributes technological knowledge to the field of Applied Sciences. The research also integrates modern power generation technologies with China's current and future energy requirements. With these objectives in mind, this project examines how China's environmental issues are related to China's power generation methods. This study then makes strategic recommendations that emphasize low-carbon technologies as sustainable energy generating options to be implemented in China. These low-carbon technologies consist of three options: (1) using cleaner fuels converted from China's plentiful domestic coal resources; (2) applying high-efficiency gas turbine systems for power generation; and (3) integrating coal gasification processes with energy saving combined cycle gas turbine systems. Each method can perform independently, but a combined strategy can achieve the greatest COsb2 reductions. To minimize economic impacts caused by technological changes, this study also addresses additional alternatives that can be implemented in

  6. 5-Hydroxytryptamine does not reduce sympathetic nerve activity or neuroeffector function in the splanchnic circulation.

    PubMed

    Darios, Emma S; Barman, Susan M; Orer, Hakan S; Morrison, Shaun F; Davis, Robert P; Seitz, Bridget M; Burnett, Robert; Watts, Stephanie W

    2015-05-01

    Infusion of 5-hydroxytryptamine (5-HT) in conscious rats results in a sustained (up to 30 days) fall in blood pressure. This is accompanied by an increase in splanchnic blood flow. Because the splanchnic circulation is regulated by the sympathetic nervous system, we hypothesized that 5-HT would: 1) directly reduce sympathetic nerve activity in the splanchnic region; and/or 2) inhibit sympathetic neuroeffector function in splanchnic blood vessels. Moreover, removal of the sympathetic innervation of the splanchnic circulation (celiac ganglionectomy) would reduce 5-HT-induced hypotension. In anaesthetized Sprague-Dawley rats, mean blood pressure was reduced from 101±4 to 63±3mm Hg during slow infusion of 5-HT (25μg/kg/min, i.v.). Pre- and postganglionic splanchnic sympathetic nerve activity were unaffected during 5-HT infusion. In superior mesenteric arterial rings prepared for electrical field stimulation, neither 5-HT (3, 10, 30nM), the 5-HT1B receptor agonist CP 93129 nor 5-HT1/7 receptor agonist 5-carboxamidotryptamine inhibited neurogenic contraction compared to vehicle. 5-HT did not inhibit neurogenic contraction in superior mesenteric venous rings. Finally, celiac ganglionectomy did not modify the magnitude of fall or time course of 5-HT-induced hypotension when compared to animals receiving sham ganglionectomy. We conclude it is unlikely 5-HT interacts with the sympathetic nervous system at the level of the splanchnic preganglionic or postganglionic nerve, as well as at the neuroeffector junction, to reduce blood pressure. These important studies allow us to rule out a direct interaction of 5-HT with the splanchnic sympathetic nervous system as a cause of the 5-HT-induced fall in blood pressure. PMID:25732865

  7. 5-Hydroxytryptamine does not reduce sympathetic nerve activity or neuroeffector function in the splanchnic circulation

    PubMed Central

    Darios, Emma S.; Barman, Susan M.; Orer, Hakan S.; Morrison, Shaun F.; Davis, Robert P.; Seitz, Bridget M.; Burnett, Robert; Watts, Stephanie W.

    2015-01-01

    Infusion of 5-hydroxytryptamine (5-HT) in conscious rats results in a sustained (up to 30 days) fall in blood pressure. This is accompanied by an increase in splanchnic blood flow. Because the splanchnic circulation is regulated by the sympathetic nervous system, we hypothesized that 5-HT would: 1) directly reduce sympathetic nerve activity in the splanchnic region; and/or 2) inhibit sympathetic neuroeffector function in splanchnic blood vessels. Moreover, removal of the sympathetic innervation of the splanchnic circulation (celiac ganglionectomy) would reduce 5-HT-induced hypotension. In anaesthetized Sprague-Dawley rats, mean blood pressure was reduced from 101 ± 4 to 63 ± 3 mm Hg during slow infusion of 5-HT (25 μg/kg/min, i.v.). Pre- and postganglionic splanchnic sympathetic nerve activity was unaffected during 5-HT infusion. In superior mesenteric arterial rings prepared for electrical field stimulation, neither 5-HT (3, 10, 30 nM), the 5-HT1B receptor agonist CP 93129 nor 5-HT1/7 receptor agonist 5-carboxamidotryptamine inhibited neurogenic contraction compared to vehicle. 5-HT did not inhibit neurogenic contraction in superior mesenteric venous rings. Finally, celiac ganglionectomy did not modify the magnitude of fall or time course of 5-HT-induced hypotension when compared to animals receiving sham ganglionectomy. We conclude it is unlikely 5-HT interacts with the sympathetic nervous system at the level of the splanchnic preganglionic or postganglionic nerve, as well as at the neuroeffector junction, to reduce blood pressure. These important studies allow us to rule out a direct interaction of 5-HT with the splanchnic sympathetic nervous system as a cause of the 5-HT-induced fall in blood pressure. PMID:25732865

  8. Personalized Strategies to Activate and Empower Patients in Health Care and Reduce Health Disparities

    PubMed Central

    Chen, Jie; Mullins, C. Daniel; Novak, Priscilla; Thomas, Stephen B.

    2015-01-01

    Designing culturally-sensitive personalized interventions is essential to sustain patients’ involvement in their treatment, and encourage patients to take an active role in their own health and health care. We consider patient activation and empowerment as a cyclical process defined through patient accumulation of knowledge, confidence, and self-determination for their own health and health care. We propose a patient-centered, multi-level activation and empowerment framework (individual-, health care professional-, community-, and health care delivery system-level) to inform the development of culturally informed personalized patient activation and empowerment (P-PAE) interventions to improve population health, and reduce racial and ethnic disparities. We discuss relevant Affordable Care Act payment and delivery policy reforms, and how they impact patient activation and empowerment. Such policies include Accountable Care Organizations and Value Based Purchasing, Patient Centered Medical Homes, and the Community Health Benefit. Challenges and possible solutions to implementing the P-PAE are discussed. Comprehensive and longitudinal data sets with consistent P-PAE measures are needed to conduct comparative effectiveness analyses to evaluate the optimal P-PAE model. We believe the P-PAE model is timely and sustainable, and will be critical to engaging patients in their treatment, developing patients’ abilities to manage their health, helping patients to express concerns and preferences regarding treatment, empowering patients to ask questions about treatment options, and building up strategic patient-provider partnerships through shared decision making. PMID:25845376

  9. Effect of gait retraining for reducing ambulatory knee load on trunk biomechanics and trunk muscle activity.

    PubMed

    Nüesch, Corina; Laffer, Dominik; Netzer, Cordula; Pagenstert, Geert; Mündermann, Annegret

    2016-06-01

    The purpose of this study was to test the hypothesis that walking with increased medio-lateral trunk sway is associated with lower external knee adduction moment and lower extremity muscle activation, and higher external ipsilateral trunk moment and trunk muscle activity than walking with normal trunk sway in healthy participants. Fifteen participants performed walking trials with normal and increased medio-lateral trunk sway. Maximum trunk sway, first maximum knee adduction moment, lateral trunk bending moment, and bilateral vastus medialis, vastus lateralis, gluteus medius, rectus abdominis, external oblique and erector spinae muscle activity were computed. Walking with increased trunk sway was associated with lower maximum knee adduction moment (95% confidence interval (CI): 0.50-0.62Nm/kg vs. 0.62-0.76Nm/kg; P<.001) and ipsilateral gluteus medius (-17%; P=.014) and erector spinae muscle activity (-24%; P=.004) and greater maximum lateral trunk bending moment (+34%; P<.001) and contralateral external oblique muscle activity (+60%; P=.009). In all participants, maximum knee adduction moment was negatively correlated and maximum trunk moment was positively correlated with maximum trunk sway. The results of this study suggest that walking with increased trunk sway not only reduces the external knee adduction moment but also alters and possibly increases the load on the trunk. Hence, load-altering biomechanical interventions should always be evaluated not only regarding their effects on the index joint but on other load-bearing joints such as the spine. PMID:27264398

  10. Personalized Strategies to Activate and Empower Patients in Health Care and Reduce Health Disparities.

    PubMed

    Chen, Jie; Mullins, C Daniel; Novak, Priscilla; Thomas, Stephen B

    2016-02-01

    Designing culturally sensitive personalized interventions is essential to sustain patients' involvement in their treatment and encourage patients to take an active role in their own health and health care. We consider patient activation and empowerment as a cyclical process defined through patient accumulation of knowledge, confidence, and self-determination for their own health and health care. We propose a patient-centered, multilevel activation and empowerment framework (individual-, health care professional-, community-, and health care delivery system-level) to inform the development of culturally informed personalized patient activation and empowerment (P-PAE) interventions to improve population health and reduce racial and ethnic disparities. We discuss relevant Affordable Care Act payment and delivery policy reforms and how they affect patient activation and empowerment. Such policies include Accountable Care Organizations and value-based purchasing, patient-centered medical homes, and the community health benefit. Challenges and possible solutions to implementing the P-PAE are discussed. Comprehensive and longitudinal data sets with consistent P-PAE measures are needed to conduct comparative effectiveness analyses to evaluate the optimal P-PAE model. We believe the P-PAE model is timely and sustainable and will be critical to engaging patients in their treatment, developing patients' abilities to manage their health, helping patients express concerns and preferences regarding treatment, empowering patients to ask questions about treatment options, and building up strategic patient-provider partnerships through shared decision making. PMID:25845376

  11. Preferential PPAR-α activation reduces neuroinflammation, and blocks neurodegeneration in vivo.

    PubMed

    Esmaeili, Mohammad A; Yadav, Shilpi; Gupta, Ravi Kr; Waggoner, Garrett R; Deloach, Abigail; Calingasan, Noel Y; Beal, M Flint; Kiaei, Mahmoud

    2016-01-15

    Neuroinflammation, immune reactivity and mitochondrial abnormalities are considered as causes and/or contributors to neuronal degeneration. Peroxisome proliferator-activated receptors (PPARs) regulate both inflammatory and multiple other pathways that are implicated in neurodegeneration. In the present study, we investigated the efficacy of fenofibrate (Tricor), a pan-PPAR agonist that activates PPAR-α as well as other PPARs. We administered fenofibrate to superoxide dismutase 1 (SOD1(G93A)) mice daily prior to any detectable phenotypes and then animal behavior, pathology and longevity were assessed. Treated animals showed a significant slowing of the progression of disease with weight loss attenuation, enhanced motor performance, delayed onset and survival extension. Histopathological analysis of the spinal cords showed that neuronal loss was significantly attenuated in fenofibrate-treated mice. Mitochondria were preserved as indicated by Cytochrome c immunostaining in the spinal cord, which maybe partly due to increased expression of the PPAR-γ co-activator 1-α. The total mRNA analysis revealed that neuroprotective and anti-inflammatory genes were elevated, while neuroinflammatory genes were down-regulated. This study demonstrates that the activation of PPAR-α action via fenofibrate leads to neuroprotection by both reducing neuroinflammation and protecting mitochondria, which leads to a significant increase in survival in SOD1(G93A) mice. Therefore, the development of therapeutic strategies to activate PPAR-α as well as other PPARs may lead to new therapeutic agents to slow or halt the progression of amyotrophic lateral sclerosis. PMID:26604138

  12. relA over-expression reduces tumorigenicity and activates apoptosis in human cancer cells

    PubMed Central

    Ricca, A; Biroccio, A; Trisciuoglio, D; Cippitelli, M; Zupi, G; Bufalo, D Del

    2001-01-01

    We previously demonstrated that bcl-2 over-expression increases the malignant behaviour of the MCF7 ADR human breast cancer cell line and enhances nuclear factor-kappa B (NF-k B) transcriptional activity. Here, we investigated the direct effect of increased NF-k B activity on the tumorigenicity of MCF7 ADR cells by over-expressing the NF-k B subunit relA/p65. Surprisingly, our results demonstrated that over-expression of relA determines a considerable reduction of the tumorigenic ability in nude mice as indicated by the tumour take and the median time of tumour appearance. In vitro studies also evidenced a reduced cell proliferation and the activation of the apoptotic programme after relA over-expression. Apoptosis was associated with the production of reactive oxygen species, and the cleavage of the specific substrate Poly-ADP-ribose-polymerrase. Our data indicate that there is no general role for NF-k B in the regulation of apoptosis and tumorigenicity. In fact, even though inhibiting NF-k B activity has been reported to be lethal to tumour cells, our findings clearly suggest that an over-induction of nuclear NF-k B activity may produce the same effect. © 2001 Cancer Research Campaign http://www.bjcancer.com PMID:11747334

  13. Nandrolone reduces activation of Notch signaling in denervated muscle associated with increased Numb expression

    SciTech Connect

    Liu, Xin-Hua; Yao, Shen; Qiao, Rui-Fang; Levine, Alice C.; Kirschenbaum, Alexander; Pan, Jiangping; Wu, Yong; Qin, Weiping; Bauman, William A.; Cardozo, Christopher P.

    2011-10-14

    Highlights: {yields} Nerve transection increased Notch signaling in paralyzed muscle. {yields} Nandrolone prevented denervation-induced Notch signaling. {yields} Nandrolone induced the expression of an inhibitor of the Notch signaling, Numb. {yields} Reduction of denervation-induced Notch signaling by nandrolone is likely through upregulation of Numb. -- Abstract: Nandrolone, an anabolic steroid, slows denervation-atrophy in rat muscle. The molecular mechanisms responsible for this effect are not well understood. Androgens and anabolic steroids activate Notch signaling in animal models of aging and thereby mitigate sarcopenia. To explore the molecular mechanisms by which nandrolone prevents denervation-atrophy, we investigated the effects of nandrolone on Notch signaling in denervated rat gastrocnemius muscle. Denervation significantly increased Notch activity reflected by elevated levels of nuclear Notch intracellular domain (NICD) and expression of Hey1 (a Notch target gene). Activation was greatest at 7 and 35 days after denervation but remained present at 56 days after denervation. Activation of Notch in denervated muscle was prevented by nandrolone associated with upregulated expression of Numb mRNA and protein. These data demonstrate that denervation activates Notch signaling, and that nandrolone abrogates this response associated with increased expression of Numb, suggesting a potential mechanism by which nandrolone reduces denervation-atrophy.

  14. The effects of stress on nuclear power plant operational decision making and training approaches to reduce stress effects

    SciTech Connect

    Mumaw, R.J.

    1994-08-01

    Operational personnel may be exposed to significant levels of stress during unexpected changes in plant state an plant emergencies. The decision making that identifies operational actions, which is strongly determined by procedures, may be affected by stress, and performance may be impaired. ER report analyzes potential effects of stress in nuclear power plant (NPP) settings, especially in the context of severe accident management (SAM). First, potential sources of stress in the NPP setting are identified. This analysis is followed by a review of the ways in which stress is likely to affect performance, with an emphasis on performance of cognitive skills that are linked to operational decision making. Finally, potential training approaches for reducing or eliminating stress effects are identified. Several training approaches have the potential to eliminate or mitigate stress effects on cognitive skill performance. First, the use of simulated events for training can reduce the novelty and uncertainty that can lead to stress and performance impairments. Second, training to make cognitive processing more efficient and less reliant on attention and memory resources can offset the reductions in these resources that occur under stressful conditions. Third, training that targets crew communications skills can reduce the likelihood that communications will fail under stress.

  15. Reduced cerebral blood flow with orthostasis precedes hypocapnic hyperpnea, sympathetic activation, and postural tachycardia syndrome.

    PubMed

    Del Pozzi, Andrew T; Schwartz, Christopher E; Tewari, Deepali; Medow, Marvin S; Stewart, Julian M

    2014-06-01

    Hyperventilation and reduced cerebral blood flow velocity can occur in postural tachycardia syndrome (POTS). We studied orthostatically intolerant patients, with suspected POTS, with a chief complaint of upright dyspnea. On the basis of our observations of an immediate reduction of cerebral blood flow velocity with orthostasis, we hypothesize that the resulting ischemic hypoxia of the carotid body causes chemoreflex activation, hypocapnic hyperpnea, sympathetic activation, and increased heart rate and blood pressure in this subset of POTS. We compared 11 dyspneic POTS subjects with 10 healthy controls during a 70° head-up tilt. In POTS subjects during initial orthostasis before blood pressure recovery; central blood volume and mean arterial pressure were reduced (P<0.025), resulting in a significant (P<0.001) decrease in cerebral blood flow velocity, which temporally preceded (17±6 s; P<0.025) a progressive increase in minute ventilation and decrease in end tidal CO2 (P<0.05) when compared with controls. Sympathoexcitation, measured by muscle sympathetic nerve activity, was increased in POTS (P<0.01) and inversely proportional to end tidal CO2 and resulted in an increase in heart rate (P<0.001), total peripheral resistance (P<0.025), and a decrease in cardiac output (P<0.025). The decrease in cerebral blood flow velocity and mean arterial pressure during initial orthostasis was greater (P<0.025) in POTS. Our data suggest that exaggerated initial central hypovolemia during initial orthostatic hypotension in POTS results in reduced cerebral blood flow velocity and postural hypocapnic hyperpnea that perpetuates cerebral ischemia. We hypothesize that sustained hypocapnia and cerebral ischemia produce sympathoexcitation, tachycardia, and a statistically significant increase in blood pressure. PMID:24711524

  16. REDUCED CEREBRAL BLOOD FLOW WITH ORTHOSTASIS PRECEDES HYPOCAPNIC HYPERPNEA, SYMPATHETIC ACTIVATION AND POTS

    PubMed Central

    Del Pozzi, Andrew T.; Schwartz, Christopher E.; Tewari, Deepali; Medow, Marvin S.; Stewart, Julian M.

    2014-01-01

    Hyperventilation, and reduced cerebral blood flow velocity can occur in postural tachycardia syndrome (POTS). We studied orthostatically intolerant patients, with suspected POTS, with a chief complaint of upright dyspnea. Based on our observations of an immediate reduction of cerebral blood flow velocity with orthostasis, we hypothesize that the resulting ischemic hypoxia of the carotid body causes chemoreflex activation, hypocapnic hyperpnea, sympathetic activation, and increased heart rate and blood pressure in this subset of POTS. We compared 11 dyspneic POTS subjects to 10 healthy controls during a 70° head-up tilt. In POTS subjects during initial orthostasis prior to BP recovery; central blood volume and mean arterial pressure were reduced (P<0.025) resulting in a significant (P<0.001) decrease in cerebral blood flow velocity, which temporally preceded (17±6 s; P<0.025) a progressive increase in minute ventilation and decrease in end tidal CO2 (P<0.05), compared to controls. Sympathoexcitation, measured by muscle sympathetic nerve activity, was increased in POTS, (P<0.01), and inversely proportional to end tidal CO2 and resulted in an increase in heart rate, (P<0.001), total peripheral resistance (P<0.025), and a decrease in cardiac output (P<0.025). The decrease in cerebral blood flow velocity and mean arterial pressure during initial orthostasis was greater (P<0.025) in POTS. Our data suggest that exaggerated initial central hypovolemia during initial orthostatic hypotension in POTS results in reduced cerebral blood flow velocity and postural hypocapnic hyperpnea that perpetuates cerebral ischemia. We hypothesize that sustained hypocapnia and cerebral ischemia produce sympathoexcitation, tachycardia and a statistically significant increase in blood pressure. PMID:24711524

  17. Isolation of a Fusarium solani mutant reduced in cutinase activity and virulence.

    PubMed Central

    Dantzig, A H; Zuckerman, S H; Andonov-Roland, M M

    1986-01-01

    Fusarium solani isolate T-8 produces an extracellular enzyme, cutinase, which catalyzes the degradation of cutin in the plant cuticle. Cutinase activity can be measured by the hydrolysis of either the artifical substrate, p-nitrophenylbutyrate (PNB), or radioactive cutin containing [14C]palmitic acid. In the present study, the culture filtrate contained basal levels of cutinase when T-8 was grown on acetate as a sole source of carbon. After mutagenesis, a cutinase-defective mutant (PNB-1) was identified by screening acetate-grown colonies for a loss of PNBase activity. The mutant possessed an 80 to 90% reduction in cutinase activity when grown for 3 to 5 days on acetate- or cutin-containing medium. Induction of cutinase by cutin or hydrolyzed cutin after growth on glucose medium was similarly reduced. Kinetic analysis indicated that cutinase from the mutant possessed a near normal Km for PNB and a 92% reduction in Vmax. Fluorography and Western blotting of 15% sodium dodecyl sulfate-polyacrylamide gels of separated 35S-labeled proteins from cutin induction medium revealed that in the mutant the 22,000-molecular-weight band corresponding to cutinase was reduced approximately 85%. The virulence of the mutant in a pea stem bioassay was decreased by 55% and was restored to nearly the parental level by the addition of purified cutinase. The data suggest that the mutant synthesizes reduced quantities of a functional and immunoreactive cutinase enzyme and that cutinase plays a critical role in infection. The PNB1 mutation may be within a regulatory gene or a promoter for cutinase. Images PMID:3782031

  18. Isohumulones, bitter acids derived from hops, activate both peroxisome proliferator-activated receptor alpha and gamma and reduce insulin resistance.

    PubMed

    Yajima, Hiroaki; Ikeshima, Emiko; Shiraki, Maho; Kanaya, Tomoka; Fujiwara, Daisuke; Odai, Hideharu; Tsuboyama-Kasaoka, Nobuyo; Ezaki, Osamu; Oikawa, Shinichi; Kondo, Keiji

    2004-08-01

    The peroxisome proliferator-activated receptors (PPARs) are dietary lipid sensors that regulate fatty acid and carbohydrate metabolism. The hypolipidemic effects of fibrate drugs and the therapeutic benefits of the thiazolidinedione drugs are due to their activation of PPARalpha and -gamma, respectively. In this study, isohumulones, the bitter compounds derived from hops that are present in beer, were found to activate PPARalpha and -gamma in transient co-transfection studies. Among the three major isohumulone homologs, isohumulone and isocohumulone were found to activate PPARalpha and -gamma. Diabetic KK-Ay mice that were treated with isohumulones (isohumulone and isocohumulone) showed reduced plasma glucose, triglyceride, and free fatty acid levels (65.3, 62.6, and 73.1%, respectively, for isohumulone); similar reductions were found following treatment with the thiazolidinedione drug, pioglitazone. Isohumulone treatment did not result in significant body weight gain, although pioglitazone treatment did increase body weight (10.6% increase versus control group). C57BL/6N mice fed a high fat diet that were treated with isohumulones showed improved glucose tolerance and reduced insulin resistance. Furthermore, these animals showed increased liver fatty acid oxidation and a decrease in size and an increase in apoptosis of their hypertrophic adipocytes. A double-blind, placebo-controlled pilot study for studying the effect of isohumulones on diabetes suggested that isohumulones significantly decreased blood glucose and hemoglobin A1c levels after 8 weeks (by 10.1 and 6.4%, respectively, versus week 0). These results suggest that isohumulones can improve insulin sensitivity in high fat diet-fed mice with insulin resistance and in patients with type 2 diabetes. PMID:15178687

  19. Microstructural development in reduced activation ferritic alloys irradiated to 200 dpa at 420$deg;C

    NASA Astrophysics Data System (ADS)

    Gelles, D. S.

    1994-09-01

    Density change and microstructural development are reported for nine reduced activation ferritic steels covering the range 2.3 to 12Cr with varying additions of V and/or W for hardening and up to 6.5 Mn for austenite stability. Specimens were examined following irradiation in FFTF/MOTA at 420°C to a dose exceeding 200 dpa. Void swelling was found, but the swelling remained at 5% or below, with the worst case in an alloy of 9Cr-2Mn-1WV. The carbide structure pinning martensite lath boundaries remained in place.

  20. Pharmacodynamic monitoring of immunosuppressive effects indicates reduced cyclosporine activity during telaprevir therapy.

    PubMed

    Roos, Katja; Gotthardt, Daniel; Giese, Thomas; Schnitzler, Paul; Stremmel, Wolfgang; Czock, David; Eisenbach, Christoph

    2014-09-01

    Drug interactions with immunosuppressive drugs are a major problem associated with protease inhibitor-based antiviral triple therapy for hepatitis C virus (HCV) reinfection after liver transplantation. In this retrospective cohort study, we analyzed biomarkers of the immunosuppressive effects of cyclosporine A (CSA) by quantifying nuclear factor of activated T cells (NFAT)-regulated gene expression during telaprevir (TVR) therapy in 5 liver transplant patients. Furthermore, dose adjustments and blood concentrations of CSA as well as the clinical course were analyzed. We observed a clear impact of TVR not only on doses and blood concentrations but also on the immunosuppressive effects of CSA. Despite apparently adequate CSA trough concentrations, the CSA peak concentration decreased to 68% (range = 44%-90%). This was associated with a 1.9-fold (1.6- to 4.1-fold) increase in the residual gene activity of NFAT-regulated genes, which indicated reduced immunosuppressive activity of CSA with TVR co-medication. The median dose of CSA was reduced to 25% (range = 16%-48%) and 31% (range = 22%-64%) after 1 and 2 weeks, respectively. The CSA drug clearance was reduced to 38.7% (range = 31.0%-49.4%). We report excellent antiviral efficacy. At the end of the observation period, all patients were HCV RNA-negative (1 patient at 18 weeks, 1 patient at 12 weeks, and 3 patients at 4 weeks after the end of therapy). Safety was acceptable, with mild acute rejection and reactivation of cytomegalovirus being the most serious adverse events. One patient with histologically proven recurrent cholestatic hepatitis before therapy underwent retransplantation during the course of antiviral therapy. In conclusion, the immunomonitoring of NFAT-regulated gene expression indicated reduced immunosuppressive activity of CSA during antiviral therapy with TVR in our cohort of liver transplant patients. Thus, the immunosuppressive effects of CSA may be overestimated if one is looking

  1. Mutations in LRP5 cause primary osteoporosis without features of OI by reducing Wnt signaling activity

    PubMed Central

    2012-01-01

    Background Primary osteoporosis is a rare childhood-onset skeletal condition whose pathogenesis has been largely unknown. We have previously shown that primary osteoporosis can be caused by heterozygous missense mutations in the Low-density lipoprotein receptor-related protein 5 (LRP5) gene, and the role of LRP5 is further investigated here. Methods LRP5 was analyzed in 18 otherwise healthy children and adolescents who had evidence of osteoporosis (manifested as reduced bone mineral density i.e. BMD, recurrent peripheral fractures and/or vertebral compression fractures) but who lacked the clinical features of osteogenesis imperfecta (OI) or other known syndromes linked to low BMD. Also 51 controls were analyzed. Methods used in the genetic analyses included direct sequencing and multiplex ligation-dependent probe amplification (MLPA). In vitro studies were performed using luciferase assay and quantitative real-time polymerase chain reaction (qPCR) to examine the effect of two novel and three previously identified mutations on the activity of canonical Wnt signaling and on expression of tryptophan hydroxylase 1 (Tph1) and 5-hydroxytryptamine (5-Htr1b). Results Two novel LRP5 mutations (c.3446 T > A; p.L1149Q and c.3553 G > A; p.G1185R) were identified in two patients and their affected family members. In vitro analyses showed that one of these novel mutations together with two previously reported mutations (p.C913fs, p.R1036Q) significantly reduced the activity of the canonical Wnt signaling pathway. Such reductions may lead to decreased bone formation, and could explain the bone phenotype. Gut-derived Lrp5 has been shown to regulate serotonin synthesis by controlling the production of serotonin rate-limiting enzyme, Tph1. LRP5 mutations did not affect Tph1 expression, and only one mutant (p.L1149Q) reduced expression of serotonin receptor 5-Htr1b (p < 0.002). Conclusions Our results provide additional information on the role of LRP5 mutations and their effects on

  2. Irradiation-induced grain growth in nanocrystalline reduced activation ferrite/martensite steel

    SciTech Connect

    Liu, W. B.; Chen, L. Q.; Zhang, C. Yang, Z. G.; Ji, Y. Z.; Zang, H.; Shen, T. L.

    2014-09-22

    In this work, we investigate the microstructure evolution of surface-nanocrystallized reduced activation ferrite/martensite steels upon high-dose helium ion irradiation (24.3 dpa). We report a significant irradiation-induced grain growth in the irradiated buried layer at a depth of 300–500 nm, rather than at the peak damage region (at a depth of ∼840 nm). This phenomenon can be explained by the thermal spike model: minimization of the grain boundary (GB) curvature resulting from atomic diffusion in the cascade center near GBs.

  3. Nitric Oxide reduces NADPH oxidase 5 (Nox5) activity by reversible S-nitrosylation

    PubMed Central

    Qian, Jin; Chen, Feng; Kovalenkov, Yevgeniy; Pandey, Deepesh; Moseleley, M. Arthur; Foster, Matthew W.; Black, Stephen M.; Venema, Richard C.; Stepp, David W.; Fulton, David J.R.

    2012-01-01

    The NADPH oxidases (Nox) are a family of transmembrane oxidoreductases that produce superoxide and other reactive oxygen species (ROS). Nox5 was the last of the conventional Nox isoforms to be identified and is a calcium-dependent enzyme that does not depend on accessory subunits for activation. Recently, Nox5 was shown to be expressed in human blood vessels and therefore the goal of current study was to determine whether nitric oxide (NO) can modulate Nox5 activity. Endogenously produced NO potently inhibited basal and stimulated Nox5 activity and inhibition was reversible with chronic, but not acute exposure to L-NAME. Nox5 activity was reduced by NO donors, iNOS, eNOS and in endothelial cells and LPS-stimulated smooth muscle cells in a manner dependent on NO concentration. ROS production was diminished by NO in an isolated enzyme activity assay replete with surplus calcium and NADPH. There was no evidence for NO-dependent changes in tyrosine nitration, glutathiolation or phosphorylation of Nox5. In contrast, there was evidence for the increased nitrosylation of Nox5 as determined by the biotin-switch assay and mass spectrometry. Four S-nitrosylation sites were identified and of these, mutation of C694 dramatically lowered Nox5 activity, NO-sensitivity and biotin-labeling. Furthermore, co-expression of the denitrosylation enzymes thioredoxin (Trx1) and GSNO reductase (GSNOR) prevented NO-dependent inhibition of Nox5. The potency of NO against other Nox enzymes was Nox1≥Nox3>Nox5>Nox2 whereas Nox4 was refractory. Collectively, these results suggest that endogenously produced NO can directly S-nitrosylate and inhibit the activity of Nox5. PMID:22387196

  4. Successful implantation after reducing matrix metalloproteinase activity in the uterine cavity

    PubMed Central

    2013-01-01

    Background Recently, the concept of recurrent implantation failure (RIF) in assisted reproductive technology has been enlarged. Chronic uterine inflammation is a known cause of implantation failure and is associated with high matrix metalloproteinase (MMP) activity in uterine cavity flushing. MMP activity of women with RIF has been reported to be higher than that of fertile women. In the present retrospective study we evaluated the efficacy of treatment for high MMP activity in the uterine cavity of patients with RIF. Methods Of the 597 patients recruited to the study, 360 patients underwent MMP measurements and 237 patients did not (control group). All patients had failed to become pregnant, despite at least two transfers of good-quality embryos. Gelatinase MMP-2 and MMP-9 activity in uterine flushing fluid was detected by enzymology (MMP test). All samples were classified into two groups (positive or negative) based on the intensity of the bands on the enzyme zymogram, which represents the degree of MMP activity. Patients who tested positive on the initial test were treated for 2 weeks with a quinolone antibiotic and a corticosteroid, and subsequently underwent a second MMP test. Negative results on the second MMP tests after treatment and subsequent rates of pregnancy and miscarriage were used to evaluate the efficacy of treatment. Data were analyzed by the Mann–Whitney U-test and the chi-square test. Results Of the patients who underwent the MMP test, 15.6% had positive results (high MMP activity). After treatment, 89.3% of patients had negative results on the second MMP test. These patients had a significantly better pregnancy rate (42.0%) than the control group (26.6%), as well as a lower miscarriage rate (28.5% vs 36.5%, respectively). Conclusions A 2-week course of antibiotics and corticosteroids effectively improves the uterine environment underlying RIF by reducing MMP activity. PMID:23663265

  5. SiC MOSFET Based Single Phase Active Boost Rectifier with Power Factor Correction for Wireless Power Transfer Applications

    SciTech Connect

    Onar, Omer C; Tang, Lixin; Chinthavali, Madhu Sudhan; Campbell, Steven L; Miller , John M.

    2014-01-01

    Wireless Power Transfer (WPT) technology is a novel research area in the charging technology that bridges the utility and the automotive industries. There are various solutions that are currently being evaluated by several research teams to find the most efficient way to manage the power flow from the grid to the vehicle energy storage system. There are different control parameters that can be utilized to compensate for the change in the impedance due to variable parameters such as battery state-of-charge, coupling factor, and coil misalignment. This paper presents the implementation of an active front-end rectifier on the grid side for power factor control and voltage boost capability for load power regulation. The proposed SiC MOSFET based single phase active front end rectifier with PFC resulted in >97% efficiency at 137mm air-gap and >95% efficiency at 160mm air-gap.

  6. Detection of glucose based on the peroxidase-like activity of reduced state carbon dots.

    PubMed

    Long, Yijuan; Wang, Xiliang; Shen, Dongjun; Zheng, Huzhi

    2016-10-01

    It was found that reduced state carbon dots (r-CDs) possessed intrinsic peroxidase-like activity, and could catalytically oxidize 3,3',5,5'-tetramethylbenzidine (TMB) by H2O2 to produce a color reaction. The effects of temperature, pH, incubating time and the concentration of H2O2 and TMB on catalytic activity of r-CDs were investigated. Finally we calculated the kinetic constant was ca. 0.00729min(-1) and applied r-CDs to glucose sensing by coupling glucose oxidase. As low as 2µM H2O2 could be detected with a linear range from 0.010 to 0.40mM via this method. This study offered a simple, sensitive, and high selectivity method for glucose determination even in serum. PMID:27474288

  7. Reducing infection in chronic leg ulcers with an activated carbon cloth dressing.

    PubMed

    Murphy, Nina

    2016-06-23

    Zorflex is a new type of antimicrobial dressing composed of 100% activated carbon cloth. It attracts and binds bacteria to its surface, enabling them to be safely removed at dressing change. It has no reported toxic effects and can be used on either a short-or long-term basis. This article describes 4 case studies in which patients with recalcitrant chronic venous leg ulcers that were prone to recurrent infection were treated with the activated carbon cloth dressing. All of the wounds had failed to respond to antimicrobial dressings containing silver, iodine or polyhexamethylene biguanide (PHMB), and were heavily exuding and painful. In all cases, the signs of infection reduced significantly within 4 weeks, resulting in good patient outcomes. PMID:27345081

  8. Reduced activation martensitic steels as a structural material for ITER test blanket

    NASA Astrophysics Data System (ADS)

    Shiba, K.; Enoeda, M.; Jitsukawa, S.

    2004-08-01

    A Japanese ITER test blanket module (TBM) is planed to use reduced-activation martensitic steel F82H. Feasibility of F82H for ITER test blanket module is discussed in this paper. Several kinds of property data, including physical properties, magnetic properties, mechanical properties and neutron-irradiation data on F82H have been obtained, and these data are complied into a database to be used for the designing of the ITER TBM. Currently obtained data suggests F82H will not have serious problems for ITER TBM. Optimization of F82H improves the induced activity, toughness and HIP resistance. Furthermore, modified F82H is resistant to temperature instability during material production.

  9. Protease-activated receptor 1 and 4 signal inhibition reduces preterm neonatal hemorrhagic brain injury

    PubMed Central

    Lekic, Tim; Klebe, Damon; McBride, Devin W; Manaenko, Anatol; Rolland, William B.; Flores, Jerry J.; Altay, Orhan; Tang, Jiping; Zhang, John H.

    2015-01-01

    Background and Purpose This study examines the role of thrombin’s protease-activated receptors (PAR)-1,-4 in mediating cyclooxygenase (COX)-2 and mammalian target of rapamycin (mTOR) following germinal matrix hemorrhage (GMH). Methods GMH was induced by intraparenchymal infusion of bacterial collagenase into the right ganglionic eminence of P7 rat pups. Animals were treated with either PAR-1, -4, COX-2, or mTOR inhibitors by 1 hour, and up to five days. Results We found increased thrombin activity 6–24 hrs after GMH, and PAR-1, -4, inhibition normalized COX-2 and mTOR by 72 hrs. Early treatment with NS398 or rapamycin substantially improved long-term outcomes in juvenile animals. Conclusions Suppressing early PAR signal transduction, and postnatal NS398 or rapamycin treatment, may help reduce GMH severity in susceptible preterm infants. PMID:25931468

  10. Reduced peroxisomal citrate synthase activity increases substrate availability for polyhydroxyalkanoate biosynthesis in plant peroxisomes.

    PubMed

    Tilbrook, Kimberley; Poirier, Yves; Gebbie, Leigh; Schenk, Peer M; McQualter, Richard B; Brumbley, Stevens M

    2014-10-01

    Polyhydroxyalkanoates (PHAs) are bacterial carbon storage polymers used as renewable, biodegradable plastics. PHA production in plants may be a way to reduce industrial PHA production costs. We recently demonstrated a promising level of peroxisomal PHA production in the high biomass crop species sugarcane. However, further production strategies are needed to boost PHA accumulation closer to commercial targets. Through exogenous fatty acid feeding of Arabidopsis thaliana plants that contain peroxisome-targeted PhaA, PhaB and PhaC enzymes from Cupriavidus necator, we show here that the availability of substrates derived from the β-oxidation cycle limits peroxisomal polyhydroxybutyrate (PHB) biosynthesis. Knockdown of peroxisomal citrate synthase activity using artificial microRNA increased PHB production levels approximately threefold. This work demonstrates that reduction of peroxisomal citrate synthase activity may be a valid metabolic engineering strategy for increasing PHA production in other plant species. PMID:24944109

  11. p38 mitogen-activated protein kinase inhibitor reduces neurocan production in cultured spinal cord astrocytes.

    PubMed

    Yamaoka, Gotaro; Morino, Tadao; Morizane, Kei; Horiuchi, Hideki; Miura, Hiromasa; Ogata, Tadanori

    2012-06-20

    Chondroitin sulfate proteoglycans are formed in scar tissue after a spinal cord injury and inhibit axon regrowth. The production of neurocan, one of these chondroitin sulfate proteoglycans, in cultured spinal cord astrocytes increased after the addition of epidermal growth factor (EGF) in a dose-dependent manner (2-200 ng/ml). In astrocytes stimulated by 20 ng/ml of EGF, neurocan production was inhibited after the addition of the p38 mitogen-activated protein kinase (MAPK) inhibitor (SB203580: 3-10 μM) in a dose-dependent manner. These results suggest that the activation of p38 MAPK is one of the mechanisms of neurocan production in EGF-stimulated astrocytes. The p38 MAPK inhibitor may reduce neurocan production and accelerate axonal regrowth after a spinal cord injury. PMID:22525836

  12. Firing of antagonist small-diameter muscle afferents reduces voluntary activation and torque of elbow flexors.

    PubMed

    Kennedy, David S; McNeil, Chris J; Gandevia, Simon C; Taylor, Janet L

    2013-07-15

    During muscle fatigue, firing of small-diameter muscle afferents can decrease voluntary activation of the fatigued muscle. However, these afferents may have a more widespread effect on other muscles in the exercising limb. We examined if the firing of fatigue-sensitive afferents from elbow extensor muscles in the same arm reduces torque production and voluntary activation of elbow flexors. In nine subjects we examined voluntary activation of elbow flexors by measuring changes in superimposed twitches evoked by transcranial magnetic stimulation of the motor cortex during brief (2-3 s) maximal voluntary contractions (MVC). Inflation of a blood pressure cuff following a 2-min sustained MVC blocked blood flow to the fatigued muscle and maintained firing of small-diameter afferents. After a fatiguing elbow flexion contraction, maximal flexion torque was lower (26.0 ± 4.4% versus 67.9 ± 5.2% of initial maximal torque; means ± s.d.; P < 0.001) and superimposed twitches were larger (4.1 ± 1.1% versus 1.8 ± 0.2% ongoing MVC, P = 0.01) with than without ischaemia. After a fatiguing elbow extensor contraction, maximal flexion torque was also reduced (82.2 ± 4.9% versus 91.4 ± 2.3% of initial maximal torque; P = 0.007), superimposed twitches were larger (2.7 ± 0.7% versus 1.3 ± 0.2% ongoing MVC; P = 0.02) and voluntary activation lower (81.6 ± 8.2% versus 95.5 ± 6.9%; P = 0.04) with than without ischaemia. After a fatiguing contraction, voluntary drive to the fatigued muscles is reduced with continued input from small-diameter muscle afferents. Furthermore, fatigue of the elbow extensor muscles decreases voluntary drive to unfatigued elbow flexors of the same arm. Therefore, firing of small-diameter muscle afferents from one muscle can affect voluntary activation and hence torque generation of another muscle in the same limb. PMID:23652589

  13. Oxidative stress-mediated antibacterial activity of graphene oxide and reduced graphene oxide in Pseudomonas aeruginosa

    PubMed Central

    Gurunathan, Sangiliyandi; Han, Jae Woong; Dayem, Ahmed Abdal; Eppakayala, Vasuki; Kim, Jin-Hoi

    2012-01-01

    Background Graphene holds great promise for potential use in next-generation electronic and photonic devices due to its unique high carrier mobility, good optical transparency, large surface area, and biocompatibility. The aim of this study was to investigate the antibacterial effects of graphene oxide (GO) and reduced graphene oxide (rGO) in Pseudomonas aeruginosa. In this work, we used a novel reducing agent, betamercaptoethanol (BME), for synthesis of graphene to avoid the use of toxic materials. To uncover the impacts of GO and rGO on human health, the antibacterial activity of two types of graphene-based material toward a bacterial model P. aeruginosa was studied and compared. Methods The synthesized GO and rGO was characterized by ultraviolet-visible absorption spectroscopy, particle-size analyzer, X-ray diffraction, scanning electron microscopy and Raman spectroscopy. Further, to explain the antimicrobial activity of graphene oxide and reduced graphene oxide, we employed various assays, such as cell growth, cell viability, reactive oxygen species generation, and DNA fragmentation. Results Ultraviolet-visible spectra of the samples confirmed the transition of GO into graphene. Dynamic light-scattering analyses showed the average size among the two types of graphene materials. X-ray diffraction data validated the structure of graphene sheets, and high-resolution scanning electron microscopy was employed to investigate the morphologies of prepared graphene. Raman spectroscopy data indicated the removal of oxygen-containing functional groups from the surface of GO and the formation of graphene. The exposure of cells to GO and rGO induced the production of superoxide radical anion and loss of cell viability. Results suggest that the antibacterial activities are contributed to by loss of cell viability, induced oxidative stress, and DNA fragmentation. Conclusion The antibacterial activities of GO and rGO against P. aeruginosa were compared. The loss of P

  14. Impaired voluntary neuromuscular activation limits muscle power in mobility-limited older adults

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Background. Age-related alterations of neuromuscular activation may contribute to deficits in muscle power and mobility function. This study assesses whether impaired activation of the agonist quadriceps and antagonist hamstrings, including amplitude- and velocity-dependent characteristics of activa...

  15. Measurement of Fine Particles From Mobile and Stationary Sources, and Reducing the Air Conditioner Power Consumption in Hybrid Electric Vehicles

    NASA Astrophysics Data System (ADS)

    Brewer, Eli Henry

    We study the PM2.5and ultrafine exhaust emissions from a new natural gas-fired turbine power facility to better understand air pollution in California. To characterize the emissions from new natural gas turbines, a series of tests were performed on a GE LMS100 gas turbine. These tests included PM2.5 and wet chemical tests for SO2/SO 3 and NH3, as well as ultrafine (less than 100 nm in diameter) particulate matter measurements. The turbine exhaust had an average particle number concentration that was 2.3x103 times higher than ambient air. The majority of these particles were nanoparticles; at the 100 nm size, stack particle concentrations were about 20 times higher than ambient, and increased to 3.9x104 times higher on average in the 2.5 - 3 nm particle size range. This study also found that ammonia emissions were higher than expected, but in compliance with permit conditions. This was possibly due to an ammonia imbalance entering the catalyst, some flue gas bypassing the catalyst, or not enough catalyst volume. SO3 accounted for an average of 23% of the total sulfur oxides emissions measured. Some of the SO3 is formed in the combustion process, it is likely that the majority formed as the SO2 in the combustion products passed across the oxidizing CO catalyst and SCR catalyst. The 100 MW turbine sampled in this study emitted particle loadings similar to those previously measured from turbines in the SCAQMD area, however, the turbine exhaust contained far more particles than ambient air. The power consumed by an air conditioner accounts for a significant fraction of the total power used by hybrid and electric vehicles especially during summer. This study examined the effect of recirculation of cabin air on power consumption of mobile air conditioners both in-lab and on-road. Real time power consumption and vehicle mileage were recorded by an On Board Diagnostic monitor and carbon balance method. Vehicle mileage improved with increased cabin air recirculation. The

  16. Reduced endogenous Ca2+ buffering speeds active zone Ca2+ signaling.

    PubMed

    Delvendahl, Igor; Jablonski, Lukasz; Baade, Carolin; Matveev, Victor; Neher, Erwin; Hallermann, Stefan

    2015-06-01

    Fast synchronous neurotransmitter release at the presynaptic active zone is triggered by local Ca(2+) signals, which are confined in their spatiotemporal extent by endogenous Ca(2+) buffers. However, it remains elusive how rapid and reliable Ca(2+) signaling can be sustained during repetitive release. Here, we established quantitative two-photon Ca(2+) imaging in cerebellar mossy fiber boutons, which fire at exceptionally high rates. We show that endogenous fixed buffers have a surprisingly low Ca(2+)-binding ratio (∼ 15) and low affinity, whereas mobile buffers have high affinity. Experimentally constrained modeling revealed that the low endogenous buffering promotes fast clearance of Ca(2+) from the active zone during repetitive firing. Measuring Ca(2+) signals at different distances from active zones with ultra-high-resolution confirmed our model predictions. Our results lead to the concept that reduced Ca(2+) buffering enables fast active zone Ca(2+) signaling, suggesting that the strength of endogenous Ca(2+) buffering limits the rate of synchronous synaptic transmission. PMID:26015575

  17. The Novel Antitubulin Agent TR-764 Strongly Reduces Tumor Vasculature and Inhibits HIF-1α Activation.

    PubMed

    Porcù, Elena; Persano, Luca; Ronca, Roberto; Mitola, Stefania; Bortolozzi, Roberta; Romagnoli, Romeo; Oliva, Paola; Basso, Giuseppe; Viola, Giampietro

    2016-01-01

    Tubulin binding agents (TBAs) are commonly used in cancer therapy as antimitotics. It has been described that TBAs, like combretastatin A-4 (CA-4), present also antivascular activity and among its derivatives we identified TR-764 as a new inhibitor of tubulin polymerization, based on the 2-(alkoxycarbonyl)-3-(3',4',5'-trimethoxyanilino)benzo[b]thiophene molecular skeleton. The antiangiogenic activity of TR-764 (1-10 nM) was tested in vitro on human umbilical endothelial cells (HUVECs), and in vivo, on the chick embryo chorioallantoic membrane (CAM) and two murine tumor models. TR-764 binding to tubulin triggers cytoskeleton rearrangement without affecting cell cycle and viability. It leads to capillary tube disruption, increased cell permeability, and cell motility reduction. Moreover it disrupts adherens junctions and focal adhesions, through mechanisms involving VE-cadherin/β-catenin and FAK/Src. Importantly, TR-764 is active in hypoxic conditions significantly reducing HIF-1α. In vivo TR-764 (1-100 pmol/egg) remarkably blocks the bFGF proangiogenic activity on CAM and shows a stronger reduction of tumor mass and microvascular density both in murine syngeneic and xenograft tumor models, compared to the lead compound CA-4P. Altogether, our results indicate that TR-764 is a novel TBA with strong potential as both antivascular and antitumor molecule that could improve the common anticancer therapies, by overcoming hypoxia-induced resistance mechanisms. PMID:27292568

  18. Reducing GBA2 Activity Ameliorates Neuropathology in Niemann-Pick Type C Mice

    PubMed Central

    Ottenhoff, Roelof; van Roomen, Cindy P. A. A.; Herrera Moro, Daniela; Claessen, Nike; Vinueza Veloz, María Fernanda; Zhou, Kuikui; Lin, Zhanmin; Mirzaian, Mina; Boot, Rolf G.; De Zeeuw, Chris I.; Overkleeft, Herman S.; Yildiz, Yildiz; Aerts, Johannes M. F. G.

    2015-01-01

    The enzyme glucocerebrosidase (GBA) hydrolyses glucosylceramide (GlcCer) in lysosomes. Markedly reduced GBA activity is associated with severe manifestations of Gaucher disease including neurological involvement. Mutations in the GBA gene have recently also been identified as major genetic risk factor for Parkinsonism. Disturbed metabolism of GlcCer may therefore play a role in neuropathology. Besides lysosomal GBA, cells also contain a non-lysosomal glucosylceramidase (GBA2). Given that the two β-glucosidases share substrates, we speculated that over-activity of GBA2 during severe GBA impairment might influence neuropathology. This hypothesis was studied in Niemann-Pick type C (Npc1-/-) mice showing secondary deficiency in GBA in various tissues. Here we report that GBA2 activity is indeed increased in the brain of Npc1-/- mice. We found that GBA2 is particularly abundant in Purkinje cells (PCs), one of the most affected neuronal populations in NPC disease. Inhibiting GBA2 in Npc1-/- mice with a brain-permeable low nanomolar inhibitor significantly improved motor coordination and extended lifespan in the absence of correction in cholesterol and ganglioside abnormalities. This trend was recapitulated, although not to full extent, by introducing a genetic loss of GBA2 in Npc1-/- mice. Our findings point to GBA2 activity as therapeutic target in NPC. PMID:26275242

  19. The Novel Antitubulin Agent TR-764 Strongly Reduces Tumor Vasculature and Inhibits HIF-1α Activation

    PubMed Central

    Porcù, Elena; Persano, Luca; Ronca, Roberto; Mitola, Stefania; Bortolozzi, Roberta; Romagnoli, Romeo; Oliva, Paola; Basso, Giuseppe; Viola, Giampietro

    2016-01-01

    Tubulin binding agents (TBAs) are commonly used in cancer therapy as antimitotics. It has been described that TBAs, like combretastatin A-4 (CA-4), present also antivascular activity and among its derivatives we identified TR-764 as a new inhibitor of tubulin polymerization, based on the 2-(alkoxycarbonyl)-3-(3′,4′,5′-trimethoxyanilino)benzo[b]thiophene molecular skeleton. The antiangiogenic activity of TR-764 (1–10 nM) was tested in vitro on human umbilical endothelial cells (HUVECs), and in vivo, on the chick embryo chorioallantoic membrane (CAM) and two murine tumor models. TR-764 binding to tubulin triggers cytoskeleton rearrangement without affecting cell cycle and viability. It leads to capillary tube disruption, increased cell permeability, and cell motility reduction. Moreover it disrupts adherens junctions and focal adhesions, through mechanisms involving VE-cadherin/β-catenin and FAK/Src. Importantly, TR-764 is active in hypoxic conditions significantly reducing HIF-1α. In vivo TR-764 (1–100 pmol/egg) remarkably blocks the bFGF proangiogenic activity on CAM and shows a stronger reduction of tumor mass and microvascular density both in murine syngeneic and xenograft tumor models, compared to the lead compound CA-4P. Altogether, our results indicate that TR-764 is a novel TBA with strong potential as both antivascular and antitumor molecule that could improve the common anticancer therapies, by overcoming hypoxia-induced resistance mechanisms. PMID:27292568

  20. Inhibition of histone deacetylase 6 activity reduces cyst growth in polycystic kidney disease.

    PubMed

    Cebotaru, Liudmila; Liu, Qiangni; Yanda, Murali K; Boinot, Clement; Outeda, Patricia; Huso, David L; Watnick, Terry; Guggino, William B; Cebotaru, Valeriu

    2016-07-01

    Abnormal proliferation of cyst-lining epithelium and increased intracystic fluid secretion via the cystic fibrosis transmembrane conductance regulator (CFTR) are thought to contribute to cyst growth in autosomal dominant polycystic kidney disease (ADPKD). Histone deacetylase 6 (HDAC6) expression and activity are increased in certain cancers, neurodegenerative diseases, and in Pkd1-mutant renal epithelial cells. Inhibition of HDAC6 activity with specific inhibitors slows cancer growth. Here we studied the effect of tubacin, a specific HDAC6 inhibitor, on cyst growth in polycystic kidney disease. Treatment with tubacin prevented cyst formation in MDCK cells, an in vitro model of cystogenesis. Cyclic AMP stimulates cell proliferation and activates intracystic CFTR-mediated chloride secretion in ADPKD. Treatment with tubacin downregulated cyclic AMP levels, inhibited cell proliferation, and inhibited cyclic AMP-activated CFTR chloride currents in MDCK cells. We also found that tubacin reduced cyst growth by inhibiting proliferation of cyst-lining epithelial cells, downregulated cyclic AMP levels, and improved renal function in a Pkd1-conditional mouse model of ADPKD. Thus, HDAC6 could play a role in cyst formation and could serve as a potential therapeutic target in ADPKD. PMID:27165822

  1. Unfolded protein response activation reduces secretion and extracellular aggregation of amyloidogenic immunoglobulin light chain

    PubMed Central

    Cooley, Christina B.; Ryno, Lisa M.; Plate, Lars; Morgan, Gareth J.; Hulleman, John D.; Kelly, Jeffery W.; Wiseman, R. Luke

    2014-01-01

    Light-chain amyloidosis (AL) is a degenerative disease characterized by the extracellular aggregation of a destabilized amyloidogenic Ig light chain (LC) secreted from a clonally expanded plasma cell. Current treatments for AL revolve around ablating the cancer plasma cell population using chemotherapy regimens. Unfortunately, this approach is limited to the ∼70% of patients who do not exhibit significant organ proteotoxicity and can tolerate chemotherapy. Thus, identifying new therapeutic strategies to alleviate LC organ proteotoxicity should allow AL patients with significant cardiac and/or renal involvement to subsequently tolerate established chemotherapy treatments. Using a small-molecule screening approach, the unfolded protein response (UPR) was identified as a cellular signaling pathway whose activation selectively attenuates secretion of amyloidogenic LC, while not affecting secretion of a nonamyloidogenic LC. Activation of the UPR-associated transcription factors XBP1s and/or ATF6 in the absence of stress recapitulates the selective decrease in amyloidogenic LC secretion by remodeling the endoplasmic reticulum proteostasis network. Stress-independent activation of XBP1s, or especially ATF6, also attenuates extracellular aggregation of amyloidogenic LC into soluble aggregates. Collectively, our results show that stress-independent activation of these adaptive UPR transcription factors offers a therapeutic strategy to reduce proteotoxicity associated with LC aggregation. PMID:25157167

  2. Circuit formation and function in the olfactory bulb of mice with reduced spontaneous afferent activity.

    PubMed

    Lorenzon, Paolo; Redolfi, Nelly; Podolsky, Michael J; Zamparo, Ilaria; Franchi, Sira Angela; Pietra, Gianluca; Boccaccio, Anna; Menini, Anna; Murthy, Venkatesh N; Lodovichi, Claudia

    2015-01-01

    The type of neuronal activity required for circuit development is a matter of significant debate. We addressed this issue by analyzing the topographic organization of the olfactory bulb in transgenic mice engineered to have very little afferent spontaneous activity due to the overexpression of the inwardly rectifying potassium channel Kir2.1 in the olfactory sensory neurons (Kir2.1 mice). In these conditions, the topography of the olfactory bulb was unrefined. Odor-evoked responses were readily recorded in glomeruli with reduced spontaneous afferent activity, although the functional maps were coarser than in controls and contributed to altered olfactory discrimination behavior. In addition, overexpression of Kir2.1 in adults induced a regression of the already refined connectivity to an immature (i.e., coarser) status. Our data suggest that spontaneous activity plays a critical role not only in the development but also in the maintenance of the topography of the olfactory bulb and in sensory information processing. PMID:25568110

  3. Reduced endogenous Ca2+ buffering speeds active zone Ca2+ signaling

    PubMed Central

    Delvendahl, Igor; Jablonski, Lukasz; Baade, Carolin; Matveev, Victor; Neher, Erwin; Hallermann, Stefan

    2015-01-01

    Fast synchronous neurotransmitter release at the presynaptic active zone is triggered by local Ca2+ signals, which are confined in their spatiotemporal extent by endogenous Ca2+ buffers. However, it remains elusive how rapid and reliable Ca2+ signaling can be sustained during repetitive release. Here, we established quantitative two-photon Ca2+ imaging in cerebellar mossy fiber boutons, which fire at exceptionally high rates. We show that endogenous fixed buffers have a surprisingly low Ca2+-binding ratio (∼15) and low affinity, whereas mobile buffers have high affinity. Experimentally constrained modeling revealed that the low endogenous buffering promotes fast clearance of Ca2+ from the active zone during repetitive firing. Measuring Ca2+ signals at different distances from active zones with ultra-high-resolution confirmed our model predictions. Our results lead to the concept that reduced Ca2+ buffering enables fast active zone Ca2+ signaling, suggesting that the strength of endogenous Ca2+ buffering limits the rate of synchronous synaptic transmission. PMID:26015575

  4. Ag/ZnO heterostructures and their photocatalytic activity under visible light: effect of reducing medium.

    PubMed

    Liu, Yangsi; Wei, Shanghai; Gao, Wei

    2015-04-28

    Decoration of ZnO by Ag is a promising method to improve its photocatalytic activity and extend the photoreactivity to the visible light. In this paper, Ag/ZnO heterostructures have been synthesised by photoreduction in various reducing mediums. When the Ag/ZnO nanocomposite arrays were obtained in the air, only a small amount of Ag was reduced. Ag nanosheets and nanoparticles were formed in the water and attached on the top and side surfaces of ZnO nanorods, forming Ag/ZnO heterostructures with a nano(sheet-rod-particle) multi-level structure. In the mixture of water and ethanol, a large amount of Ag nanoclusters was produced and embedded in the ZnO nanorod arrays. The influence of reducing mediums on the microstructure, morphology, quantity and dispersion of Ag nanostructures was investigated; and the effect of Ag component on the optical properties and visible light driven photocatalytic behaviour of the Ag/ZnO heterostructures was discussed. PMID:25621832

  5. Pretreatment with alum or powdered activated carbon reduces bacterial predation-associated irreversible fouling of membranes.

    PubMed

    Kim, Eun-Ho; Dwidar, Mohammed; Kwon, Young-Nam; Mitchell, Robert J

    2014-01-01

    This study evaluated the co-application of bacterial predation by Bdellovibrio bacteriovorus and either alum coagulation or powdered activated carbon adsorption to reduce fouling caused by Escherichia coli rich feed solutions in dead-end microfiltration tests. The flux increased when the samples were predated upon or treated with 100 ppm alum or PAC, but co-treatment with alum and predation gave the best flux results. The total membrane resistance caused by the predated sample was reduced six-fold when treated with 100 ppm PAC, from 11.8 to 1.98 × 10(11) m(-1), while irreversible fouling (Rp) was 2.7-fold lower. Treatment with 100 ppm alum reduced the total resistance 14.9-fold (11.8 to 0.79 × 10(11) m(-1)) while the Rp decreased 4.25-fold. SEM imaging confirmed this, with less obvious fouling of the membrane after the combined process. This study illustrates that the combination of bacterial predation and the subsequent removal of debris using coagulation or adsorption mitigates membrane biofouling and improves membrane performance. PMID:25410737

  6. Shear stress reduces protease activated receptor-1 expression in human endothelial cells

    NASA Technical Reports Server (NTRS)

    Nguyen, K. T.; Eskin, S. G.; Patterson, C.; Runge, M. S.; McIntire, L. V.

    2001-01-01

    Shear stress has been shown to regulate several genes involved in the thrombotic and proliferative functions of endothelial cells. Thrombin receptor (protease-activated receptor-1: PAR-1) increases at sites of vascular injury, which suggests an important role for PAR-1 in vascular diseases. However, the effect of shear stress on PAR-1 expression has not been previously studied. This work investigates effects of shear stress on PAR-1 gene expression in both human umbilical vein endothelial cells (HUVECs) and microvascular endothelial cells (HMECs). Cells were exposed to different shear stresses using a parallel plate flow system. Northern blot and flow cytometry analysis showed that shear stress down-regulated PAR-1 messenger RNA (mRNA) and protein levels in both HUVECs and HMECs but with different thresholds. Furthermore, shear-reduced PAR-1 mRNA was due to a decrease of transcription rate, not increased mRNA degradation. Postshear stress release of endothelin-1 in response to thrombin was reduced in HUVECs and HMECs. Moreover, inhibitors of potential signaling pathways applied during shear stress indicated mediation of the shear-decreased PAR-1 expression by protein kinases. In conclusion, shear stress exposure reduces PAR-1 gene expression in HMECs and HUVECs through a mechanism dependent in part on protein kinases, leading to altered endothelial cell functional responses to thrombin.

  7. Laquinimod decreases Bax expression and reduces caspase-6 activation in neurons.

    PubMed

    Ehrnhoefer, Dagmar E; Caron, Nicholas S; Deng, Yu; Qiu, Xiaofan; Tsang, Michelle; Hayden, Michael R

    2016-09-01

    Laquinimod is an immunomodulatory compound that has shown neuroprotective benefits in clinical trials for multiple sclerosis. Laquinimod ameliorates both white and gray matter damage in human patients, and prevents axonal degeneration in animal models of multiple sclerosis. Axonal damage and white matter loss are a common feature shared between different neurodegenerative diseases. Caspase-6 activation plays an important role in axonal degeneration on the molecular level. Increased activity of caspase-6 has been demonstrated in brain tissue from presymptomatic Huntington disease mutation carriers, and it is an early marker of axonal dysfunction. Since laquinimod is currently undergoing a clinical trial in Huntington disease (LEGATO-HD, clinicaltrials.gov ID: NCT02215616), we set out to evaluate its impact on neuronal caspase-6 activation. We find that laquinimod ameliorates DNA-damage induced activation of caspase-6 in primary neuronal cultures. This is an indirect effect that is not mediated by direct inhibition of the enzyme. The investigation of potential caspase-6 activating mechanisms revealed that laquinimod reduces the expression of Bax, a pro-apoptotic molecule that causes mitochondrial cytochrome c release and caspase activation. Bax expression is furthermore increased in striatal tissues from the YAC128 mouse model of HD in an age-dependent manner. Our results demonstrate that laquinimod can directly downregulate neuronal apoptosis pathways relevant for axonal degeneration in addition to its known effects on astrocytes and microglia in the CNS. It targets a pathway that is relevant for the pathogenesis of HD, supporting the hypothesis that laquinimod may provide clinical benefit. PMID:27296315

  8. Dopamine Depletion Reduces Food-Related Reward Activity Independent of BMI.

    PubMed

    Frank, Sabine; Veit, Ralf; Sauer, Helene; Enck, Paul; Friederich, Hans-Christoph; Unholzer, Theresa; Bauer, Ute-Maria; Linder, Katarzyna; Heni, Martin; Fritsche, Andreas; Preissl, Hubert

    2016-05-01

    Reward sensitivity and possible alterations in the dopaminergic-reward system are associated with obesity. We therefore aimed to investigate the influence of dopamine depletion on food-reward processing. We investigated 34 female subjects in a randomized placebo-controlled, within-subject design (body mass index (BMI)=27.0 kg/m(2) ±4.79 SD; age=28 years ±4.97 SD) using an acute phenylalanine/tyrosine depletion drink representing dopamine depletion and a balanced amino acid drink as the control condition. Brain activity was measured with functional magnetic resonance imaging during a 'wanting' and 'liking' rating of food items. Eating behavior-related traits and states were assessed on the basis of questionnaires. Dopamine depletion resulted in reduced activation in the striatum and higher activation in the superior frontal gyrus independent of BMI. Brain activity during the wanting task activated a more distributed network than during the liking task. This network included gustatory, memory, visual, reward, and frontal regions. An interaction effect of dopamine depletion and the wanting/liking task was observed in the hippocampus. The interaction with the covariate BMI was significant in motor and control regions but not in the striatum. Our results support the notion of altered brain activity in the reward and prefrontal network with blunted dopaminergic action during food-reward processing. This effect is, however, independent of BMI, which contradicts the reward-deficiency hypothesis. This hints to the hypothesis suggesting a different or more complex mechanism underlying the dopaminergic reward function in obesity. PMID:26450814

  9. T396I Mutation of Mouse Sufu Reduces the Stability and Activity of Gli3 Repressor

    PubMed Central

    Makino, Shigeru; Zhulyn, Olena; Mo, Rong; Puviindran, Vijitha; Zhang, Xiaoyun; Murata, Takuya; Fukumura, Ryutaro; Ishitsuka, Yuichi; Kotaki, Hayato; Matsumaru, Daisuke; Ishii, Shunsuke; Hui, Chi-Chung; Gondo, Yoichi

    2015-01-01

    Hedgehog signaling is primarily transduced by two transcription factors: Gli2, which mainly acts as a full-length activator, and Gli3, which tends to be proteolytically processed from a full-length form (Gli3FL) to an N-terminal repressor (Gli3REP). Recent studies using a Sufu knockout mouse have indicated that Sufu is involved in regulating Gli2 and Gli3 activator and repressor activity at multiple steps of the signaling cascade; however, the mechanism of specific Gli2 and Gli3 regulation remains to be elucidated. In this study, we established an allelic series of ENU-induced mouse strains. Analysis of one of the missense alleles, SufuT396I, showed that Thr396 residue of Sufu played a key role in regulation of Gli3 activity. SufuT396I/T396I embryos exhibited severe polydactyly, which is indicative of compromised Gli3 activity. Concomitantly, significant quantitative reductions of unprocessed Gli3 (Gli3FL) and processed Gli3 (Gli3REP) were observed in vivo as well as in vitro. Genetic experiments showed that patterning defects in the limb buds of SufuT396I/T396I were rescued by a constitutive Gli3REP allele (Gli3∆699), strongly suggesting that SufuT396I reduced the truncated Gli3 repressor. In contrast, SufuT396I qualitatively exhibited no mutational effects on Gli2 regulation. Taken together, the results of this study show that the Thr396 residue of Sufu is specifically required for regulation of Gli3 but not Gli2. This implies a novel Sufu-mediated mechanism in which Gli2 activator and Gli3 repressor are differentially regulated. PMID:25760946

  10. Chemically active reduced graphene oxide with tunable C/O ratios.

    PubMed

    Compton, Owen C; Jain, Bonny; Dikin, Dmitriy A; Abouimrane, Ali; Amine, Khalil; Nguyen, Sonbinh T

    2011-06-28

    Organic dispersions of graphene oxide can be thermally reduced in polar organic solvents under reflux conditions to afford electrically conductive, chemically active reduced graphene oxide (CARGO) with tunable C/O ratios, dependent on the boiling point of the solvent. The reductions are achieved after only 1 h of reflux, and the corresponding C/O ratios do not change upon further thermal treatment. Hydroxyl and carboxyl groups can be removed when the reflux is carried out above 155 °C, while epoxides are removable only when the temperature is higher than 200 °C. The increasing hydrophobic nature of CARGO, as its C/O ratio increases, improves the dispersibility of the nanosheets in a polystyrene matrix, in contrast to the aggregates formed with CARGO having lower C/O ratios. The excellent processability of the obtained CARGO dispersions is demonstrated via free-standing CARGO papers that exhibit tunable electrical conductivity/chemical activity and can be used as lithium-ion battery anodes with enhanced Coulombic efficiency. PMID:21473647

  11. Reduced lymphocyte activation in space: role of cell-substratum interactions.

    PubMed

    Gmünder, F K; Kiess, M; Sonnenfeld, G; Lee, J; Cogoli, A

    1992-01-01

    We investigated the effect of substratum adhesiveness on stimulated lymphocyte blastogenesis by reducing and blocking cell adhesion with poly (2-hydroxyethyl methacrylate) (poly-HEMA) in a simple on-ground system. Cells grown on medium-thick and thick poly-HEMA films were rounded in shape and displayed no signs of spreading. By contrast, on tissue culture plastic and very thin poly-HEMA films, they showed clear signs of spreading. The mitogenic response of lymphocytes grown on thick poly-HEMA films was reduced by up to 68% of the control (tissue culture plastic). Interferon-gamma production was near zero when the cells were grown on the least adhesive substratum. On uncoated plastic, activated lymphocytes subjected to high gravity (20g) exhibited an increased proliferation rate (40%) compared with 1g. By contrast, on poly-HEMA, high gravity did not improve lymphocyte responsiveness. These results show that activated lymphocytes need to anchor and spread prior to achieving an optimal proliferation response. We conclude that decreased lymphocyte adhesion could contribute to the depressed in vitro lymphocyte responsiveness found in the microgravity conditions of space flight. PMID:11536989

  12. Exceptionally strong sorption of infochemicals to activated carbon reduces their bioavailability to fish.

    PubMed

    Jonker, Michiel T O; van Mourik, Louise

    2014-03-01

    The addition of activated carbon (AC) to sediments is a relatively new approach to remediate contaminated sites. Activated carbon strongly sorbs hydrophobic organic contaminants, thereby reducing their bioavailability and uptake in organisms. Because of its high sorption capacity, AC might, however, also sorb other chemicals that are not contaminants but instead have ecological functions. Examples of such compounds are infochemicals or pheromones (i.e., compounds serving as chemical inter- and intraspecies information vectors). The present study investigated the sorption of 2 known infochemicals, hypoxanthine-3-N-oxide (H3NO) and pyridine-N-oxide (PNO), to 5 different powdered ACs. Sorption isotherms of these low-molecular-weight, polar fish kairomone substances appeared highly nonlinear, with logarithmic Freundlich sorption coefficients of up to 7.6. At physiologically relevant concentrations, sorption was up to 7 to 9 orders of magnitude stronger than expected on the basis of hydrophobic forces only (i.e., the compounds' log octanol-water partition coefficient, being approximately -1), indicating exceptionally strong binding to specific sites. This binding effectively reduced the bioavailability of H3NO to Sarasa goldfish, as was shown in a behavioral assay. The present study demonstrates the previously unrecognized potential of AC to sorb ecologically relevant chemicals. Whether this potential may lead to subtle, unwanted ecological effects in the field will have to be investigated in more detail during future research. PMID:24272993

  13. Joining techniques for a reduced activation 12Cr steel for inertial fusion energy

    SciTech Connect

    Hunt, R. M.; El-Dasher, B.; Choi, B. W.; Torres, S. G.

    2014-10-01

    At Lawrence Livermore National Laboratory, we are developing a reduced activation ferritic martensitic steel that is based on the ferritic martensitic steel HT-9. As a part of the development of this steel, we tested a series of welding processes for characterization, including conventional welds (electron beam, tungsten inert gas, and laser) as well as solid-state welds (hot isostatic pressing). We also heat treated the joints at various temperatures between 750 °C and 1050 °C to find a suitable normalization scheme. The modified HT-9 reduced activation ferritic martensitic steel appears highly suitable to welding and diffusion bonding. All welds showed good quality fusion zones with insignificant cracking or porosity. Additionally, a heat treatment schedule of 950 °C for one hour caused minimal grain growth while still converging the hardness of the base metal with that of the fusion and heat-affected zones. Also, modified HT-9 diffusion bonds that were created at temperatures of at least 950 °C for two hours at 103 MPa had interface tensile strengths of greater than 600 MPa. The diffusion bonds showed no evidence of increased hardness nor void formation at the diffusion bonded interface.

  14. ACE inhibition reduces infarction in normotensive but not hypertensive rats: correlation with cortical ACE activity

    PubMed Central

    Porritt, Michelle J; Chen, Michelle; Rewell, Sarah S J; Dean, Rachael G; Burrell, Louise M; Howells, David W

    2010-01-01

    Angiotensin-converting enzyme (ACE) inhibition can reduce stroke risk by up to 43% in humans and reduce the associated disability, and hence understanding the mechanism of improvement is important. In animals and humans, these effects may be independent of the blood pressure-lowering effects of ACE inhibition. Normotensive (Wistar–Kyoto (WKY)) and hypertensive (spontaneously hypertensive rat (SHR)) animals were treated with the ACE inhibitors ramipril or lisinopril for 7 or 42 days before 2 hours of transient middle cerebral artery occlusion (MCAo). Blood pressure, serum ACE, and blood glucose levels were measured and stroke infarct volume was recorded 24 hours after stroke. Despite greater reductions in blood pressure, infarct size was not improved by ACE inhibition in hypertensive animals. Short-term ACE inhibition produced only a modest reduction in blood pressure, but WKY rats showed marked reductions in infarct volume. Long-term ACE inhibition had additional reductions in blood pressure; however, infarct volumes in WKY rats did not improve further but worsened. WKY rats differed from SHR in having marked cortical ACE activity that was highly sensitive to ACE inhibition. The beneficial effects of ACE inhibition on infarct volume in normotensive rats do not correlate with changes in blood pressure. However, WKY rats have ACE inhibitor-sensitive cortical ACE activity that is lacking in the SHR. PMID:20407464

  15. Reduced posterior parietal cortex activation after training on a visual search task.

    PubMed

    Bueichekú, Elisenda; Miró-Padilla, Anna; Palomar-García, María-Ángeles; Ventura-Campos, Noelia; Parcet, María-Antonia; Barrós-Loscertales, Alfonso; Ávila, César

    2016-07-15

    Gaining experience on a cognitive task improves behavioral performance and is thought to enhance brain efficiency. Despite the body of literature already published on the effects of training on brain activation, less research has been carried out on visual search attention processes under well controlled conditions. Thirty-six healthy adults divided into trained and control groups completed a pre-post letter-based visual search task fMRI study in one day. Twelve letters were used as targets and ten as distractors. The trained group completed a training session (840 trials) with half the targets between scans. The effects of training were studied at the behavioral and brain levels by controlling for repetition effects using both between-subjects (trained vs. control groups) and within-subject (trained vs. untrained targets) controls. The trained participants reduced their response speed by 31% as a result of training, maintaining their accuracy scores, whereas the control group hardly changed. Neural results revealed that brain changes associated with visual search training were circumscribed to reduced activation in the posterior parietal cortex (PPC) when controlling for group, and they included inferior occipital areas when controlling for targets. The observed behavioral and brain changes are discussed in relation to automatic behavior development. The observed training-related decreases could be associated with increased neural efficiency in specific key regions for task performance. PMID:27132048

  16. Oxytocin reduces neural activity in the pain circuitry when seeing pain in others

    PubMed Central

    Hermans, Erno J.; Keysers, Christian; van Honk, Jack

    2015-01-01

    Our empathetic abilities allow us to feel the pain of others. This phenomenon of vicarious feeling arises because the neural circuitry of feeling pain and seeing pain in others is shared. The neuropeptide oxytocin (OXT) is considered a robust facilitator of empathy, as intranasal OXT studies have repeatedly been shown to improve cognitive empathy (e.g. mind reading and emotion recognition). However, OXT has not yet been shown to increase neural empathic responses to pain in others, a core aspect of affective empathy. Effects of OXT on empathy for pain are difficult to predict, because OXT evidently has pain-reducing properties. Accordingly, OXT might paradoxically decrease empathy for pain. Here, using functional neuroimaging we show robust activation in the neural circuitry of pain (insula and sensorimotor regions) when subjects observe pain in others. Crucially, this empathy-related activation in the neural circuitry of pain is strongly reduced after intranasal OXT, specifically in the left insula. OXT on the basis of our neuroimaging data thus remarkably decreases empathy for pain, but further research including behavioral measures are necessary to draw definite conclusions. PMID:25818690

  17. Increased activity correlates with reduced ability to mount immune defenses to endotoxin in zebra finches.

    PubMed

    Lopes, Patricia C; Springthorpe, Dwight; Bentley, George E

    2014-10-01

    When suffering from infection, animals experience behavioral and physiological alterations that potentiate the immune system's ability to fight pathogens. The behavioral component of this response, termed "sickness behavior," is characterized by an overall reduction in physical activity. A growing number of reports demonstrate substantial flexibility in these sickness behaviors, which can be partially overcome in response to mates, intruders and parental duties. Since it is hypothesized that adopting sickness behaviors frees energetic resources for mounting an immune response, we tested whether diminished immune responses coincided with reduced sickness behaviors by housing male zebra finches (Taeniopygia guttata) in social conditions that alter their behavioral response to an endotoxin. To facilitate our data collection, we developed and built a miniaturized sensor capable of detecting changes in dorsoventral acceleration and categorizing them as different behaviors when attached to the finches. We found that the immune defenses (quantified as haptoglobin-like activity, ability to change body temperature and bacterial killing capacity) increased as a function of increased time spent resting. The findings indicate that when animals are sick attenuation of sickness behaviors may exact costs, such as reduced immune function. The extent of these costs depends on how relevant the affected components of immunity are for fighting a specific infection. PMID:24888267

  18. Oxytocin reduces neural activity in the pain circuitry when seeing pain in others.

    PubMed

    Bos, Peter A; Montoya, Estrella R; Hermans, Erno J; Keysers, Christian; van Honk, Jack

    2015-06-01

    Our empathetic abilities allow us to feel the pain of others. This phenomenon of vicarious feeling arises because the neural circuitry of feeling pain and seeing pain in others is shared. The neuropeptide oxytocin (OXT) is considered a robust facilitator of empathy, as intranasal OXT studies have repeatedly been shown to improve cognitive empathy (e.g. mind reading and emotion recognition). However, OXT has not yet been shown to increase neural empathic responses to pain in others, a core aspect of affective empathy. Effects of OXT on empathy for pain are difficult to predict, because OXT evidently has pain-reducing properties. Accordingly, OXT might paradoxically decrease empathy for pain. Here, using functional neuroimaging we show robust activation in the neural circuitry of pain (insula and sensorimotor regions) when subjects observe pain in others. Crucially, this empathy-related activation in the neural circuitry of pain is strongly reduced after intranasal OXT, specifically in the left insula. OXT on the basis of our neuroimaging data thus remarkably decreases empathy for pain, but further research including behavioral measures is necessary to draw definite conclusions. PMID:25818690

  19. Major depression in mothers predict reduced ventral striatum activation in adolescent female offspring with and without depression

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Prior research has identified reduced reward-related brain activation as a promising endophenotype for the early identification of adolescents with major depressive disorder. However, it is unclear whether reduced reward-related brain activation constitutes a true vulnerability for major depressive ...

  20. Activation of Rap1 inhibits NADPH oxidase-dependent ROS generation in retinal pigment epithelium and reduces choroidal neovascularization

    PubMed Central

    Wang, Haibo; Jiang, Yanchao; Shi, Dallas; Quilliam, Lawrence A.; Chrzanowska-Wodnicka, Magdalena; Wittchen, Erika S.; Li, Dean Y.; Hartnett, M. Elizabeth

    2014-01-01

    Activation of Rap1 GTPase can improve the integrity of the barrier of the retina pigment epithelium (RPE) and reduce choroidal neovascularization (CNV). Inhibition of NADPH oxidase activation also reduces CNV. We hypothesize that Rap1 inhibits NADPH oxidase-generated ROS and thereby reduces CNV formation. Using a murine model of laser-induced CNV, we determined that reduced Rap1 activity in RPE/choroid occurred with CNV formation and that activation of Rap1 by 2′-O-Me-cAMP (8CPT)-reduced laser-induced CNV via inhibiting NADPH oxidase-generated ROS. In RPE, inhibition of Rap1 by Rap1 GTPase-activating protein (Rap1GAP) increased ROS generation, whereas activation of Rap1 by 8CPT reduced ROS by interfering with the assembly of NADPH oxidase membrane subunit p22phox with NOX4 or cytoplasmic subunit p47phox. Activation of NADPH oxidase with Rap1GAP reduced RPE barrier integrity via cadherin phosphorylation and facilitated choroidal EC migration across the RPE monolayer. Rap1GAP-induced ROS generation was inhibited by active Rap1a, but not Rap1b, and activation of Rap1a by 8CPT in Rap1b−/− mice reduced laser-induced CNV, in correlation with decreased ROS generation in RPE/choroid. These findings provide evidence that active Rap1 reduces CNV by interfering with the assembly of NADPH oxidase subunits and increasing the integrity of the RPE barrier.—Wang, H., Jiang, Y., Shi, D., Quilliam, L. A., Chrzanowska-Wodnicka, M., Wittchen, E. S., Li, D. Y., Hartnett, M. E. Activation of Rap1 inhibits NADPH oxidase-dependent ROS generation in retinal pigment epithelium and reduces choroidal neovascularization. PMID:24043260

  1. Jujuboside B Reduces Vascular Tension by Increasing Ca2+ Influx and Activating Endothelial Nitric Oxide Synthase.

    PubMed

    Zhao, Yixiu; Zhang, Xin; Li, Jiannan; Bian, Yu; Sheng, Miaomiao; Liu, Bin; Fu, Zidong; Zhang, Yan; Yang, Baofeng

    2016-01-01

    Jujuboside B has been reported to have protective effect on many cardiovascular diseases. However, the effects of Jujuboside B on vascular tension and endothelial function are unknown. The present study investigated the effects of Jujuboside B on reducing vascular tension, protecting endothelial function and the potential mechanisms. The tension of isolated rat thoracic aorta ring was measured by Wire myograph system. The concentration of nitric oxide (NO) and the activity of endothelial nitric oxide synthase (eNOS) in human aortic endothelial cells (HAECs) were determined by Griess reagent method and enzyme-linked immune sorbent assay. The protein levels of eNOS and p-eNOS at Serine-1177 were determined by western blot analysis. Intracellular Ca2+ concentration in HAECs was measured by laser confocal imaging microscopy. Results showed that Jujuboside B reduced the tension of rat thoracic aorta rings with intact endothelium in a dose-dependent manner. L-NAME, KN93, EGTA, SKF96365, iberiotoxin and glibenclamide significantly attenuated Jujuboside B-induced vasodilation in endothelium-intact tissues. In contrast, indometacin and 4-DAMP had no such effects. Jujuboside B also promoted NO generation and increased eNOS activity, which were attenuated by L-NAME, EGTA and SKF96365. Moreover, Jujuboside B increased intracellular Ca2+ concentration dose-dependently, which was inhibited by EGTA and SKF96365. Besides, Jujuboside B induced a rapid Ca2+ influx instantaneously after depleting intracellular Ca2+ store, which was significantly inhibited by SKF96365. In conclusion, this study preliminarily confirmed that Jujuboside B reduced vascular tension endothelium-dependently. The underlying mechanisms involved that Jujuboside B increased extracellular Ca2+ influx through endothelial transient receptor potential cation (TRPC) channels, phosphorylated eNOS and promoted NO generation in vascular endothelial cells. In addition, Jujuboside B-induced vasodilation involved

  2. Jujuboside B Reduces Vascular Tension by Increasing Ca2+ Influx and Activating Endothelial Nitric Oxide Synthase

    PubMed Central

    Zhao, Yixiu; Zhang, Xin; Li, Jiannan; Bian, Yu; Sheng, Miaomiao; Liu, Bin; Fu, Zidong; Zhang, Yan; Yang, Baofeng

    2016-01-01

    Jujuboside B has been reported to have protective effect on many cardiovascular diseases. However, the effects of Jujuboside B on vascular tension and endothelial function are unknown. The present study investigated the effects of Jujuboside B on reducing vascular tension, protecting endothelial function and the potential mechanisms. The tension of isolated rat thoracic aorta ring was measured by Wire myograph system. The concentration of nitric oxide (NO) and the activity of endothelial nitric oxide synthase (eNOS) in human aortic endothelial cells (HAECs) were determined by Griess reagent method and enzyme-linked immune sorbent assay. The protein levels of eNOS and p-eNOS at Serine-1177 were determined by western blot analysis. Intracellular Ca2+ concentration in HAECs was measured by laser confocal imaging microscopy. Results showed that Jujuboside B reduced the tension of rat thoracic aorta rings with intact endothelium in a dose-dependent manner. L-NAME, KN93, EGTA, SKF96365, iberiotoxin and glibenclamide significantly attenuated Jujuboside B-induced vasodilation in endothelium-intact tissues. In contrast, indometacin and 4-DAMP had no such effects. Jujuboside B also promoted NO generation and increased eNOS activity, which were attenuated by L-NAME, EGTA and SKF96365. Moreover, Jujuboside B increased intracellular Ca2+ concentration dose-dependently, which was inhibited by EGTA and SKF96365. Besides, Jujuboside B induced a rapid Ca2+ influx instantaneously after depleting intracellular Ca2+ store, which was significantly inhibited by SKF96365. In conclusion, this study preliminarily confirmed that Jujuboside B reduced vascular tension endothelium-dependently. The underlying mechanisms involved that Jujuboside B increased extracellular Ca2+ influx through endothelial transient receptor potential cation (TRPC) channels, phosphorylated eNOS and promoted NO generation in vascular endothelial cells. In addition, Jujuboside B-induced vasodilation involved

  3. Reduced nitrate leaching and enhanced denitrifier activity and efficiency in organically fertilized soils

    PubMed Central

    Kramer, Sasha B.; Reganold, John P.; Glover, Jerry D.; Bohannan, Brendan J. M.; Mooney, Harold A.

    2006-01-01

    Conventional agriculture has improved in crop yield but at large costs to the environment, particularly off-site pollution from mineral N fertilizers. In response to environmental concerns, organic agriculture has become an increasingly popular option. One component of organic agriculture that remains in question is whether it can reduce agricultural N losses to groundwater and the atmosphere relative to conventional agriculture. Here we report reduced N pollution from organic and integrated farming systems compared with a conventional farming system. We evaluated differences in denitrification potential and a suite of other soil biological and chemical properties in soil samples taken from organic, integrated, and conventional treatments in an experimental apple orchard. Organically farmed soils exhibited higher potential denitrification rates, greater denitrification efficiency, higher organic matter, and greater microbial activity than conventionally farmed soils. The observed differences in denitrifier function were then assessed under field conditions after fertilization. N2O emissions were not significantly different among treatments; however, N2 emissions were highest in organic plots. Annual nitrate leaching was 4.4–5.6 times higher in conventional plots than in organic plots, with the integrated plots in between. This study demonstrates that organic and integrated fertilization practices support more active and efficient denitrifier communities, shift the balance of N2 emissions and nitrate losses, and reduce environmentally damaging nitrate losses. Although this study specifically examines a perennial orchard system, the ecological and biogeochemical processes we evaluated are present in all agroecosystems, and the reductions in nitrate loss in this study could also be achievable in other cropping systems. PMID:16537377

  4. Reduced nitrate leaching and enhanced denitrifier activity and efficiency in organically fertilized soils.

    PubMed

    Kramer, Sasha B; Reganold, John P; Glover, Jerry D; Bohannan, Brendan J M; Mooney, Harold A

    2006-03-21

    Conventional agriculture has improved in crop yield but at large costs to the environment, particularly off-site pollution from mineral N fertilizers. In response to environmental concerns, organic agriculture has become an increasingly popular option. One component of organic agriculture that remains in question is whether it can reduce agricultural N losses to groundwater and the atmosphere relative to conventional agriculture. Here we report reduced N pollution from organic and integrated farming systems compared with a conventional farming system. We evaluated differences in denitrification potential and a suite of other soil biological and chemical properties in soil samples taken from organic, integrated, and conventional treatments in an experimental apple orchard. Organically farmed soils exhibited higher potential denitrification rates, greater denitrification efficiency, higher organic matter, and greater microbial activity than conventionally farmed soils. The observed differences in denitrifier function were then assessed under field conditions after fertilization. N(2)O emissions were not significantly different among treatments; however, N(2) emissions were highest in organic plots. Annual nitrate leaching was 4.4-5.6 times higher in conventional plots than in organic plots, with the integrated plots in between. This study demonstrates that organic and integrated fertilization practices support more active and efficient denitrifier communities, shift the balance of N(2) emissions and nitrate losses, and reduce environmentally damaging nitrate losses. Although this study specifically examines a perennial orchard system, the ecological and biogeochemical processes we evaluated are present in all agroecosystems, and the reductions in nitrate loss in this study could also be achievable in other cropping systems. PMID:16537377

  5. Bandwidth improvement of high power uni-traveling-carrier photodiodes by reducing the series resistance and capacitance

    NASA Astrophysics Data System (ADS)

    Li, Jin; Xiong, Bing; Sun, Chang-Zheng; Luo, Yi; Wang, Jian; Hao, Zhi-Biao; Han, Yan-Jun; Wang, Lai; Li, Hong-Tao

    2015-07-01

    A backside illuminated mesa-structure InGaAs/InP modified uni-traveling-carrier photodiode (MUTC-PD) with wide bandwidth and high saturation power is fabricated and investigated. The device structure is optimized to reduce the capacitance and resistance. For the 22-μm-diameter device, the maximum responsivity at 1.55 μm is 0.5 A/W, and the 3-dB cutoff frequency reaches up to 28 GHz. The output photocurrent at the 1-dB compression point is measured to be 54 mA at 25 GHz, with a corresponding output radio frequency (RF) power of up to 15.5 dBm. The saturation characteristics of the MUTC-PD are also verified by the electric field simulation, and electric field collapse is found to be the cause of the saturation phenomenon. Project supported by the National Basic Research Program of China (Grant Nos. 2012CB315605 and 2014CB340002), the National Natural Science Foundation of China (Grant Nos. 61176015, 61176059, 61210014, 61321004, and 61307024), and the Open Fund of State Key Laboratory on Integrated Optoelectronics, China (Grant Nos. IOSKL2012KF08 and IOSKL2014KF09).

  6. Initial Activation and Operation of the Power Conditioning System for the National Ignition Facility

    SciTech Connect

    Newton, M A; Kamm, R E; Fulkerson, E S; Hulsey, S D; Lao, N; Parrish, G L; Pendleton, D L; Petersen, D E; Polk, M; Tuck, J M; Ullery, G T; Moore, W B

    2003-08-20

    The NIF Power Conditioning System (PCS) resides in four Capacitor Bays, supplying energy to the Master and Power Amplifiers which reside in the two adjacent laser bays. Each capacitor bay will initially house 48 individual power conditioning modules, shown in Figure 2, with space reserved for expansion to 54 modules. The National Ignition Facility (NIF) Power Conditioning System (PCS) is a modular capacitive energy storage system that will be capable of storing nearly 400 MJ of electrical energy and delivering that energy to the nearly 8000 flashlamps in the NIF laser. The first sixteen modules of the power conditioning system have been built, tested and installed. Activation of the first nine power conditioning modules has been completed and commissioning of the first ''bundle'' of laser beamlines has begun. This paper will provide an overview of the power conditioning system design and describe the status and results of initial testing and activation of the first ''bundle'' of power conditioning modules.

  7. ERC product improvement activities for direct fuel cell power plants

    SciTech Connect

    Maru, H.C.; Farooque, M.; Bentley, C.

    1995-12-01

    This program is designed to advance the carbonate fuel cell technology from the current power plant demonstration status to the commercial design in an approximately five-year period. The specific objectives which will allow attainment of the overall program goal are: (1) Define market-responsive power plant requirements and specifications, (2) Establish the design for a multifuel, low-cost, modular, market-responsive power plant, (3) Resolve power plant manufacturing issues and define the design for the commercial manufacturing facility, (4) Define the stack and BOP equipment packaging arrangement and define module designs, (5) Acquire capability to support developmental testing of stacks and BOP equipment as required to prepare for commercial design, and (6) Resolve stack and BOP equipment technology issues and design, build, and field test a modular commercial prototype power plant to demonstrate readiness for commercial entry. A seven-task program, dedicated to attaining objective(s) in the areas noted above, was initiated in December 1994. Accomplishments of the first six months are discussed in this paper.

  8. ERC product improvement activities for direct fuel cell power plants

    SciTech Connect

    Bentley, C.; Carlson, G.; Doyon, J.

    1995-08-01

    This program is designed to advance the carbonate fuel cell technology from the current power plant demonstration status to the commercial design in an approximately five-year period. The specific objectives which will allow attainment of the overall program goal are: (1) Define market-responsive power plant requirements and specifications, (2) Establish the design for a multifuel, low-cost, modular, market-responsive power plant, (3) Resolve power plant manufacturing issues and define the design for the commercial manufacturing facility, (4) Define the stack and BOP equipment packaging arrangement and define module designs, (5) Acquire capability to support developmental testing of stacks and BOP equipment as required to prepare for commercial design, and (6) Resolve stack and BOP equipment technology issues and design, build, and field test a modular commercial prototype power plant to demonstrate readiness for commercial entry. A seven-task program, dedicated to attaining objective(s) in the areas noted above, was initiated in December 1994. Accomplishments of the first six months are discussed in this paper.

  9. A Plasminogen Activator Inhibitor-1 Inhibitor Reduces Airway Remodeling in a Murine Model of Chronic Asthma

    PubMed Central

    Lee, Sun H.; Eren, Mesut; Vaughan, Douglas E.; Schleimer, Robert P.

    2012-01-01

    We previously reported that plasminogen activator inhibitor (PAI)-1 deficiency prevents collagen deposition in the airways of ovalbumin (OVA)-challenged mice. In this study, we explored the therapeutic utility of blocking PAI-1 in preventing airway remodeling, using a specific PAI-1 inhibitor, tiplaxtinin. C57BL/6J mice were immunized with intraperitoneal injections of OVA on Days 0, 3, and 6. Starting on Day 11, mice were challenged with phosphate-buffered saline or OVA by nebulization three times per week for 4 weeks. Tiplaxtinin was mixed with chow and administered orally from 1 day before the phosphate-buffered saline or OVA challenge. Lung tissues were harvested after challenge and characterized histologically for infiltrating inflammatory cells, mucus-secreting goblet cells, and collagen deposition. Airway hyperresponsiveness was measured using whole-body plethysmography. Tiplaxtinin treatment significantly decreased levels of PAI-1 activity in bronchoalveolar lavage fluids, which indicates successful blockage of PAI-1 activity in the airways. The number of infiltrated inflammatory cells was reduced by tiplaxtinin treatment in the lungs of the OVA-challenged mice. Furthermore, oral administration of tiplaxtinin significantly attenuated the degree of goblet cell hyperplasia and collagen deposition in the airways of the OVA-challenged mice, and methacholine-induced airway hyperresponsiveness was effectively reduced by tiplaxtinin in these animals. This study supports our previous findings that PAI-1 promotes airway remodeling in a murine model of chronic asthma, and suggests that PAI-1 may be a novel target of treatment of airway remodeling in asthma. PMID:22323366

  10. A plasminogen activator inhibitor-1 inhibitor reduces airway remodeling in a murine model of chronic asthma.

    PubMed

    Lee, Sun H; Eren, Mesut; Vaughan, Douglas E; Schleimer, Robert P; Cho, Seong H

    2012-06-01

    We previously reported that plasminogen activator inhibitor (PAI)-1 deficiency prevents collagen deposition in the airways of ovalbumin (OVA)-challenged mice. In this study, we explored the therapeutic utility of blocking PAI-1 in preventing airway remodeling, using a specific PAI-1 inhibitor, tiplaxtinin. C57BL/6J mice were immunized with intraperitoneal injections of OVA on Days 0, 3, and 6. Starting on Day 11, mice were challenged with phosphate-buffered saline or OVA by nebulization three times per week for 4 weeks. Tiplaxtinin was mixed with chow and administered orally from 1 day before the phosphate-buffered saline or OVA challenge. Lung tissues were harvested after challenge and characterized histologically for infiltrating inflammatory cells, mucus-secreting goblet cells, and collagen deposition. Airway hyperresponsiveness was measured using whole-body plethysmography. Tiplaxtinin treatment significantly decreased levels of PAI-1 activity in bronchoalveolar lavage fluids, which indicates successful blockage of PAI-1 activity in the airways. The number of infiltrated inflammatory cells was reduced by tiplaxtinin treatment in the lungs of the OVA-challenged mice. Furthermore, oral administration of tiplaxtinin significantly attenuated the degree of goblet cell hyperplasia and collagen deposition in the airways of the OVA-challenged mice, and methacholine-induced airway hyperresponsiveness was effectively reduced by tiplaxtinin in these animals. This study supports our previous findings that PAI-1 promotes airway remodeling in a murine model of chronic asthma, and suggests that PAI-1 may be a novel target of treatment of airway remodeling in asthma. PMID:22323366

  11. Activation of the chicken gonadotropin-inhibitory hormone receptor reduces gonadotropin releasing hormone receptor signaling.

    PubMed

    Shimizu, Mamiko; Bédécarrats, Grégoy Y

    2010-06-01

    Gonadotropin-inhibitory hormone (GnIH) is a hypothalamic peptide from the RFamide peptide family that has been identified in multiple avian species. Although GnIH has clearly been shown to reduce LH release from the anterior pituitary gland, its mechanism of action remains to be determined. The overall objectives of this study were (1) to characterize the GnIH receptor (GnIH-R) signaling pathway, (2) to evaluate potential interactions with gonadotropin releasing hormone type III receptor (GnRH-R-III) signaling, and (3) to determine the molecular mechanisms by which GnIH and GnRH regulate pituitary gonadotrope function during a reproductive cycle in the chicken. Using real-time PCR, we showed that in the chicken pituitary gland, GnIH-R mRNA levels fluctuate in an opposite manner to GnRH-R-III, with higher and lower levels observed during inactive and active reproductive stages, respectively. We demonstrated that the chicken GnIH-R signals by inhibiting adenylyl cyclase cAMP production, most likely by coupling to G(alphai). We also showed that this inhibition is sufficient to significantly reduce GnRH-induced cAMP responsive element (CRE) activation in a dose-dependent manner, and that the ratio of GnRH/GnIH receptors is a significant factor. We propose that in avian species, sexual maturation is characterized by a change in GnIH/GnRH receptor ratio, resulting in a switch in pituitary sensitivity from inhibitory (involving GnIH) to stimulatory (involving GnRH). In turn, decreasing GnIH-R signaling, combined with increasing GnRH-R-III signaling, results in significant increases in CRE activation, possibly initiating gonadotropin synthesis. PMID:20350548

  12. Reduced proliferative and differentiative activity of mouse pink-eyed dilution melanoblasts is related to apoptosis.

    PubMed

    Hirobe, Tomohisa; Terunuma, Emi

    2012-11-01

    The mouse pink-eyed dilution (p) locus is known to control the melanin content, melanosome morphology, and tyrosinase activity in melanocytes. However, it is not well known whether the p allele is involved in regulating melanocyte proliferation, differentiation, and death. The aim of this study is to investigate in detail the role of the p allele in melanocyte proliferation, differentiation, and death using a cell culture system. The epidermal cell suspensions of the neonatal dorsal skin derived from wild type mice at the p locus (black, C57BL/10JHir-P/P) and their congenic mutant (pink-eyed dilution, C57BL/10JHir-p/p) were cultured with serum-free melanoblast-proliferation medium (MDMDF) and melanocyte-proliferation medium (MDMD). The proliferation and differentiation of p/p melanoblasts in MDMDF or MDMD were greatly inhibited compared with those of P/P melanoblasts and melanocytes. It is possible that apoptosis is related to the reduced proliferative and differentiative activity of p/p melanoblasts/melanocytes. The addition of apoptosis-inhibitors, such as caspase-9 inhibitor (C9I) and Bax-inhibiting peptide (BIP) into MDMDF or MDMD stimulated the proliferation and differentiation of p/p melanoblasts. In contrast, in P/P melanoblasts and melanocytes, C9I and BIP failed to stimulate their proliferation and differentiation. The number of apoptotic keratinocytes and melanoblasts/melanocytes in p/p mice was greater than in P/P mice. Moreover, expression of C9 and Bax in keratinocytes and melanoblasts/melanocytes in p/p mice was greater than in P/P mice. These results suggest that the increased apoptosis in keratinocytes and melanoblasts/melanocytes is related to the reduced proliferative and differentiative activity of p/p melanoblasts. PMID:23106556

  13. Spinal cord stimulation reduces mechanical hyperalgesia and glial cell activation in animals with neuropathic pain

    PubMed Central

    Sato, Karina L.; Johanek, Lisa M.; Sanada, Luciana S.; Sluka, Kathleen A.

    2015-01-01

    Spinal cord stimulation (SCS) is used to manage chronic intractable neuropathic pain. We examined parameters of SCS in rats with spared nerve injury by modulating frequency (4Hz vs. 60Hz), duration (30m vs. 6h), or intensity (50%, 75%, or 90% MT). To elucidate potential mechanisms modulated by SCS, we examined immunoreactivity glial markers in the spinal cord after SCS). An epidural SCS lead was implanted in the upper lumbar spinal cord. Animals were tested for mechanical withdrawal threshold (MWT) of the paw before and 2 weeks after SNI, before and after SCS daily for 4 days, and for 9 days after SCS. Seperate groups of animals were tested for glial immunoreactivity after 4 days of 6h SCS. All rats showed a decrease in MWT 2 weeks after nerve injury and an increase in glial activation. For frequency, 4Hz or 60Hz SCS reversed the MWT when compared to sham SCS. For duration, 6h of SCS showed a greater reduction in MWT when compared to 30 min. For intensity, 90% MT was greater than 75% MT and both were greater than 50% MT or sham SCS. SCS decreased glial activation (GFAP, MCP-1 and OX-42) in the spinal cord dorsal horn when compared to sham. In conclusion, 4Hz and 60Hz SCS for a 6h at 90% MT were the most effective parameters for reducing hyperalgesia, suggesting parameters of stimulation are important for effectiveness of SCS. SCS reduced glial activation at the level of the spinal cord suggesting reduction in central excitability. PMID:24361846

  14. Mutation in E1, the Ubiquitin Activating Enzyme, Reduces Drosophila Lifespan and Results in Motor Impairment

    PubMed Central

    Liu, Hsiu-Yu; Pfleger, Cathie M.

    2013-01-01

    Neurodegenerative diseases cause tremendous suffering for those afflicted and their families. Many of these diseases involve accumulation of mis-folded or aggregated proteins thought to play a causal role in disease pathology. Ubiquitinated proteins are often found in these protein aggregates, and the aggregates themselves have been shown to inhibit the activity of the proteasome. These and other alterations in the Ubiquitin Pathway observed in neurodegenerative diseases have led to the question of whether impairment of the Ubiquitin Pathway on its own can increase mortality or if ongoing neurodegeneration alters Ubiquitin Pathway function as a side-effect. To address the role of the Ubiquitin Pathway in vivo, we studied loss-of-function mutations in the Drosophila Ubiquitin Activating Enzyme, Uba1 or E1, the most upstream enzyme in the Ubiquitin Pathway. Loss of only one functional copy of E1 caused a significant reduction in adult lifespan. Rare homozygous hypomorphic E1 mutants reached adulthood. These mutants exhibited further reduced lifespan and showed inappropriate Ras activation in the brain. Removing just one functional copy of Ras restored the lifespan of heterozygous E1 mutants to that of wild-type flies and increased the survival of homozygous E1 mutants. E1 homozygous mutants also showed severe motor impairment. Our findings suggest that processes that impair the Ubiquitin Pathway are sufficient to cause early mortality. Reduced lifespan and motor impairment are seen in the human disease X-linked Infantile Spinal Muscular Atrophy, which is associated with mutation in human E1 warranting further analysis of these mutants as a potential animal model for study of this disease. PMID:23382794

  15. Efficient degradation of trichloroethylene in water using persulfate activated by reduced graphene oxide-iron nanocomposite.

    PubMed

    Ahmad, Ayyaz; Gu, Xiaogang; Li, Li; Lv, Shuguang; Xu, Yisheng; Guo, Xuhong

    2015-11-01

    Graphene oxide (GO) and nano-sized zero-valent iron-reduced graphene oxide (nZVI-rGO) composite were prepared. The GO and nZVI-rGO composite were characterized by transmission electron microscopy (TEM), Fourier transform infrared (FTIR), energy-dispersive spectroscopy (EDS), and Raman spectroscopy. The size of nZVI was about 6 nm as observed by TEM. The system of nZVI-rGO and persulfate (PS) was used for the degradation of trichloroethylene (TCE) in water, and showed 26.5% more efficiency as compared to nZVI/PS system. The different parameters were studied to determine the efficiency of nZVI-rGO to activate the PS system for the TCE degradation. By increasing the PS amount, TCE removal was also improved while no obvious effect was observed by varying the catalyst loading. Degradation was decreased as the TCE initial concentration was increased from 20 to 100 mg/L. Moreover, when initial solution pH was increased, efficiency deteriorated to 80%. Bicarbonate showed more negative effect on TCE removal among the solution matrix. To better understand the effects of radical species in the system, the scavenger tests were performed. The •SO4(-) and •O2(-) were predominant species responsible for TCE removal. The nZVI-rGO-activated PS process shows potential applications in remediation of highly toxic organic contaminants such as TCE present in the groundwater. Graphical abstract Persulfate activated by reduced graphene oxide and nano-sized zero-valent iron composite can be used for efficient degradation of trichloroethylene (TCE) in water. PMID:26162447

  16. A practical cooling strategy for reducing the physiological strain associated with firefighting activity in the heat.

    PubMed

    Barr, D; Gregson, W; Sutton, L; Reilly, T

    2009-04-01

    The aim of this study was to establish whether a practical cooling strategy reduces the physiological strain during simulated firefighting activity in the heat. On two separate occasions under high ambient temperatures (49.6 +/- 1.8 degrees C, relative humidity (RH) 13 +/- 2%), nine male firefighters wearing protective clothing completed two 20-min bouts of treadmill walking (5 km/h, 7.5% gradient) separated by a 15-min recovery period, during which firefighters were either cooled (cool) via application of an ice vest and hand and forearm water immersion ( approximately 19 degrees C) or remained seated without cooling (control). There was no significant difference between trials in any of the dependent variables during the first bout of exercise. Core body temperature (37.72 +/- 0.34 vs. 38.21 +/- 0.17 degrees C), heart rate (HR) (81 +/- 9 vs. 96 +/- 17 beats/min) and mean skin temperature (31.22 +/- 1.04 degrees C vs. 33.31 +/- 1 degrees C) were significantly lower following the recovery period in cool compared with control (p < 0.05). Core body temperature remained consistently lower (0.49 +/- 0.02 degrees C; p < 0.01) throughout the second bout of activity in cool compared to control. Mean skin temperature, HR and thermal sensation were significantly lower during bout 2 in cool compared with control (p < 0.05). It is concluded that this practical cooling strategy is effective at reducing the physiological strain associated with demanding firefighting activity under high ambient temperatures. PMID:19401892

  17. O-GlcNAc modification of PPAR{gamma} reduces its transcriptional activity

    SciTech Connect

    Ji, Suena; Park, Sang Yoon; Roth, Juergen; Kim, Hoe Suk; Cho, Jin Won

    2012-01-27

    Highlights: Black-Right-Pointing-Pointer We found that PPAR{gamma} is modified by O-GlcNAc in 3T3-L1 adipocytes. Black-Right-Pointing-Pointer The Thr54 of PPAR{gamma}1 is the major O-GlcNAc site. Black-Right-Pointing-Pointer Transcriptional activity of PPAR{gamma}1 was decreased on treatment with the OGA inhibitor. -- Abstract: The peroxisome proliferator-activated receptor {gamma} (PPAR{gamma}), a member of the nuclear receptor superfamily, is a key regulator of adipogenesis and is important for the homeostasis of the adipose tissue. The {beta}-O-linked N-acetylglucosamine (O-GlcNAc) modification, a posttranslational modification on various nuclear and cytoplasmic proteins, is involved in the regulation of protein function. Here, we report that PPAR{gamma} is modified by O-GlcNAc in 3T3-L1 adipocytes. Mass spectrometric analysis and mutant studies revealed that the threonine 54 of the N-terminal AF-1 domain of PPAR{gamma} is the major O-GlcNAc site. Transcriptional activity of wild type PPAR{gamma} was decreased 30% by treatment with the specific O-GlcNAcase (OGA) inhibitor, but the T54A mutant of PPAR{gamma} did not respond to inhibitor treatment. In 3T3-L1 cells, an increase in O-GlcNAc modification by OGA inhibitor reduced PPAR{gamma} transcriptional activity and terminal adipocyte differentiation. Our results suggest that the O-GlcNAc state of PPAR{gamma} influences its transcriptional activity and is involved in adipocyte differentiation.

  18. Passive stretch reduces calpain activity through nitric oxide pathway in unloaded soleus muscles.

    PubMed

    Xu, Peng-Tao; Li, Quan; Sheng, Juan-Juan; Chang, Hui; Song, Zhen; Yu, Zhi-Bin

    2012-08-01

    Unloading in spaceflight or long-term bed rest induces to pronounced atrophy of anti-gravity skeletal muscles. Passive stretch partially resists unloading-induced atrophy of skeletal muscle, but the mechanism remains elusive. The aims of this study were to investigate the hypotheses that stretch tension might increase protein level of neuronal nitric oxide synthase (nNOS) in unloaded skeletal muscle, and then nNOS-derived NO alleviated atrophy of skeletal muscle by inhibiting calpain activity. The tail-suspended rats were used to unload rat hindlimbs for 2 weeks, at the same time, left soleus muscle was stretched by applying a plaster cast to fix the ankle at 35° dorsiflexion. Stretch partially resisted atrophy and inhibited the decreased protein level and activity of nNOS in unloaded soleus muscles. Unloading increased frequency of calcium sparks and elevated intracellular resting and caffeine-induced Ca(2+) concentration ([Ca(2+)]i) in unloaded soleus muscle fibers. Stretch reduced frequency of calcium sparks and restored intracellular resting and caffeine-induced Ca(2+) concentration to control levels in unloaded soleus muscle fibers. The increased protein level and activity of calpain as well as the higher degradation of desmin induced by unloading were inhibited by stretch in soleus muscles. In conclusion, these results suggest that stretch can preserve the stability of sarcoplasmic reticulum Ca(2+) release channels which prevents the elevated [Ca(2+)]i by means of keeping nNOS activity, and then the enhanced protein level and activity of calpain return to control levels in unloaded soleus muscles. Therefore, stretch can resist in part atrophy of unloaded soleus muscles. PMID:22547201

  19. Preliminary evidence of reduced brain network activation in patients with post-traumatic migraine following concussion.

    PubMed

    Kontos, Anthony P; Reches, Amit; Elbin, R J; Dickman, Dalia; Laufer, Ilan; Geva, Amir B; Shacham, Galit; DeWolf, Ryan; Collins, Michael W

    2016-06-01

    Post-traumatic migraine (PTM) (i.e., headache, nausea, light and/or noise sensitivity) is an emerging risk factor for prolonged recovery following concussion. Concussions and migraine share similar pathophysiology characterized by specific ionic imbalances in the brain. Given these similarities, patients with PTM following concussion may exhibit distinct electrophysiological patterns, although researchers have yet to examine the electrophysiological brain activation in patients with PTM following concussion. A novel approach that may help differentiate brain activation in patients with and without PTM is brain network activation (BNA) analysis. BNA involves an algorithmic analysis applied to multichannel EEG-ERP data that provides a network map of cortical activity and quantitative data during specific tasks. A prospective, repeated measures design was used to evaluate BNA (during Go/NoGo task), EEG-ERP, cognitive performance, and concussion related symptoms at 1, 2, 3, and 4 weeks post-injury intervals among athletes with a medically diagnosed concussion with PTM (n = 15) and without (NO-PTM) (n = 22); and age, sex, and concussion history matched controls without concussion (CONTROL) (n = 20). Participants with PTM had significantly reduced BNA compared to NO-PTM and CONTROLS for Go and NoGo components at 3 weeks and for NoGo component at 4 weeks post-injury. The PTM group also demonstrated a more prominent deviation of network activity compared to the other two groups over a longer period of time. The composite BNA algorithm may be a more sensitive measure of electrophysiological change in the brain that can augment established cognitive assessment tools for detecting impairment in individuals with PTM. PMID:26091725

  20. Increasing Level of Leisure Physical Activity Could Reduce the Risk of Hip Fracture in Older Women

    PubMed Central

    Rong, Ke; Liu, Xiao-yu; Wu, Xu-hua; Li, Xiao-liu; Xia, Qing-quan; Chen, Jiong; Yin, Xiao-fan

    2016-01-01

    Abstract We carried out the study to investigate and quantitatively assess the potential association between current level of physical activity and the risk of osteoporosis hip fracture in older women. Relevant publications before October 2015 were identified using the PubMed and Ovid searching tools. A dose–response meta-analysis was carried out to combine and analysis results. Fourteen prospective studies were included in the meta-analysis. A general analysis of 9 studies showed a significant inverse relationship between increasing level of physical activity and risk of hip fracture in older women [relative risk (RR) = 0.93, 95% confidence interval (95% CI): 0.91–0.96]. The result of a sensitivity analysis was consistent with the general analysis (RR = 0.94, 95% CI: 0.93–0.96). The association between increasing level of physical activity and risk of wrist fracture was not statistically significant in a general analysis of three studies (RR = 1.004, 95% CI: 0.98–1.03). A potential direct association between increasing level of physical activity and risk of wrist fracture was observed after removing 1 study with the greatest weight (RR = 1.01, 95% CI: 1.00–1.03). No significant publication bias was observed in our analysis. Our results show that increasing level of physical activity within an appropriate range may reduce the risk of hip fracture but not the risk of wrist fracture in older women. PMID:26986111

  1. Biotransformation of Bisphenol AF to Its Major Glucuronide Metabolite Reduces Estrogenic Activity

    PubMed Central

    Yin, Jie; Zhang, Jing; Feng, Yixing; Shao, Bing

    2013-01-01

    Bisphenol AF (BPAF), an endocrine disrupting chemical, can induce estrogenic activity through binding to estrogen receptor (ER). However, the metabolism of BPAF in vivo and the estrogenic activity of its metabolites remain unknown. In the present study, we identified four metabolites including BPAF diglucuronide, BPAF glucuronide (BPAF-G), BPAF glucuronide dehydrated and BPAF sulfate in the urine of Sprague-Dawley (SD) rats. BPAF-G was further characterized by nuclear magnetic resonance (NMR). After treatment with a single dose of BPAF, BPAF was metabolized rapidly to BPAF-G, as detected in the plasma of SD rats. Biotransformation of BPAF to BPAF-G was confirmed with human liver microsomes (HLM), and Vmax of glucuronidation for HLM was 11.6 nmol/min/mg. We also found that BPAF glucuronidation could be mediated through several human recombinant UDP-glucuronosyltransferases (UGTs) including UGT1A1, UGT1A3, UGT1A8, UGT1A9, UGT2B4, UGT2B7, UGT2B15 and UGT2B17, among which UGT2B7 showed the highest efficiency of glucuronidation. To explain the biological function of BPAF biotransformation, the estrogenic activities of BPAF and BPAF-G were evaluated in ER-positive breast cancer T47D and MCF7 cells. BPAF significantly stimulates ER-regulated gene expression and cell proliferation at the dose of 100 nM and 1 μM in breast cancer cells. However, BPAF-G did not show any induction of estrogenic activity at the same dosages, implying that formation of BPAF-G is a potential host defense mechanism against BPAF. Based on our study, biotransformation of BPAF to BPAF-G can eliminate BPAF-induced estrogenic activity, which is therefore considered as reducing the potential threat to human beings. PMID:24349450

  2. Biotransformation of bisphenol AF to its major glucuronide metabolite reduces estrogenic activity.

    PubMed

    Li, Ming; Yang, Yunjia; Yang, Yi; Yin, Jie; Zhang, Jing; Feng, Yixing; Shao, Bing

    2013-01-01

    Bisphenol AF (BPAF), an endocrine disrupting chemical, can induce estrogenic activity through binding to estrogen receptor (ER). However, the metabolism of BPAF in vivo and the estrogenic activity of its metabolites remain unknown. In the present study, we identified four metabolites including BPAF diglucuronide, BPAF glucuronide (BPAF-G), BPAF glucuronide dehydrated and BPAF sulfate in the urine of Sprague-Dawley (SD) rats. BPAF-G was further characterized by nuclear magnetic resonance (NMR). After treatment with a single dose of BPAF, BPAF was metabolized rapidly to BPAF-G, as detected in the plasma of SD rats. Biotransformation of BPAF to BPAF-G was confirmed with human liver microsomes (HLM), and Vmax of glucuronidation for HLM was 11.6 nmol/min/mg. We also found that BPAF glucuronidation could be mediated through several human recombinant UDP-glucuronosyltransferases (UGTs) including UGT1A1, UGT1A3, UGT1A8, UGT1A9, UGT2B4, UGT2B7, UGT2B15 and UGT2B17, among which UGT2B7 showed the highest efficiency of glucuronidation. To explain the biological function of BPAF biotransformation, the estrogenic activities of BPAF and BPAF-G were evaluated in ER-positive breast cancer T47D and MCF7 cells. BPAF significantly stimulates ER-regulated gene expression and cell proliferation at the dose of 100 nM and 1 μM in breast cancer cells. However, BPAF-G did not show any induction of estrogenic activity at the same dosages, implying that formation of BPAF-G is a potential host defense mechanism against BPAF. Based on our study, biotransformation of BPAF to BPAF-G can eliminate BPAF-induced estrogenic activity, which is therefore considered as reducing the potential threat to human beings. PMID:24349450

  3. Hydrocarbon activation under sulfate-reducing and methanogenic conditions proceeds by different mechanisms.

    NASA Astrophysics Data System (ADS)

    Head, Ian; Gray, Neil; Aitken, Caroline; Sherry, Angela; Jones, Martin; Larter, Stephen

    2010-05-01

    Microbial degradation of alkanes typically involves their conversion to fatty acids which are then catabolised by beta-oxidation. The critical step in this process is activation of the hydrocarbon. Under oxic conditions this is catalyzed by monooxygenase enzymes with the formation of long chain alcohols. In the absence of oxygen alternative alkane activation mechanisms have been observed or proposed. Fumarate addition to alkanes to form alkyl succinates is considered a central process in anaerobic hydrocarbon degradation. Comparative studies of crude oil degradation under sulphate-reducing and methanogenic conditions revealed distinctive patterns of compound class removal and metabolite formation. Alkyl succinates derived from C7 to C26 n-alkanes and branched chain alkanes were found in abundance in sulfate-reducing systems but these were not detected during methanogenic crude oil degradation. Only one other mechanism of alkane activation has been elucidated to date. This involves addition of carbon derived from bicarbonate/CO2 to C-3 of an alkane chain to form a 2-ethylalkane with subsequent removal of the ethyl group leading to the formation of a fatty acid 1 carbon shorter than the original alkane. 2-ethylalkanes have never been detected as metabolites of anaerobic alkane degradation and were not detected in crude oil-degrading methanogenic systems. Due to the range of alkanes present in crude oil it was not possible to infer the generation of C-odd acids from C-even alkanes which is characteristic of the C-3 carboxylation mechanism. Furthermore genes homologous to alkysuccinate synthetases were not detected in the methanogenic hydrocarbon degrading community by pyrosequencing of total DNA extracted from methanogenic enrichments cultures. beta-oxidation genes were detected and intriguingly, alcohol and aldehyde dehydrogenase genes were present. This offers the possibility that alkane activation in the methanogenic system does not proceed via acid metabolites

  4. Video-Quality Estimation Based on Reduced-Reference Model Employing Activity-Difference

    NASA Astrophysics Data System (ADS)

    Yamada, Toru; Miyamoto, Yoshihiro; Senda, Yuzo; Serizawa, Masahiro

    This paper presents a Reduced-reference based video-quality estimation method suitable for individual end-user quality monitoring of IPTV services. With the proposed method, the activity values for individual given-size pixel blocks of an original video are transmitted to end-user terminals. At the end-user terminals, the video quality of a received video is estimated on the basis of the activity-difference between the original video and the received video. Psychovisual weightings and video-quality score adjustments for fatal degradations are applied to improve estimation accuracy. In addition, low-bit-rate transmission is achieved by using temporal sub-sampling and by transmitting only the lower six bits of each activity value. The proposed method achieves accurate video quality estimation using only low-bit-rate original video information (15kbps for SDTV). The correlation coefficient between actual subjective video quality and estimated quality is 0.901 with 15kbps side information. The proposed method does not need computationally demanding spatial and gain-and-offset registrations. Therefore, it is suitable for real-time video-quality monitoring in IPTV services.

  5. Reduced Sensory Oscillatory Activity during Rapid Auditory Processing as a Correlate of Language-Learning Impairment

    PubMed Central

    Heim, Sabine; Friedman, Jennifer Thomas; Keil, Andreas; Benasich, April A.

    2010-01-01

    Successful language acquisition has been hypothesized to involve the ability to integrate rapidly presented, brief acoustic cues in sensory cortex. A body of work has suggested that this ability is compromised in language-learning impairment (LLI). The present research aimed to examine sensory integration during rapid auditory processing by means of electrophysiological measures of oscillatory brain activity using data from a larger longitudinal study. Twenty-nine children with LLI and control participants with typical language development (n=18) listened to tone doublets presented at a temporal interval that is essential for accurate speech processing (70-ms interstimulus interval). The children performed a deviant (pitch change of second tone) detection task, or listened passively. The electroencephalogram was recorded from 64 electrodes. Data were source-projected to the auditory cortices and submitted to wavelet analysis, resulting in time-frequency representations of electrocortical activity. Results show significantly reduced amplitude and phase-locking of early (45–75 ms) oscillations in the gamma-band range (29–52 Hz), specifically in the LLI group, for the second stimulus of the tone doublet. This suggests altered temporal organization of sensory oscillatory activity in LLI when processing rapid sequences. PMID:21822356

  6. Reduced cholesterol levels impair Smoothened activation in Smith–Lemli–Opitz syndrome

    PubMed Central

    Blassberg, Robert; Macrae, James I.; Briscoe, James; Jacob, John

    2016-01-01

    Smith–Lemli–Opitz syndrome (SLOS) is a common autosomal-recessive disorder that results from mutations in the gene encoding the cholesterol biosynthetic enzyme 7-dehydrocholesterol reductase (DHCR7). Impaired DHCR7 function is associated with a spectrum of congenital malformations, intellectual impairment, epileptiform activity and autism spectrum disorder. Biochemically, there is a deficit in cholesterol and an accumulation of its metabolic precursor 7-dehydrocholesterol (7DHC) in developing tissues. Morphological abnormalities in SLOS resemble those seen in congenital Sonic Hedgehog (SHH)-deficient conditions, leading to the proposal that the pathogenesis of SLOS is mediated by aberrant SHH signalling. SHH signalling is transduced through the transmembrane protein Smoothened (SMO), which localizes to the primary cilium of a cell on activation and is both positively and negatively regulated by sterol molecules derived from cholesterol biosynthesis. One proposed mechanism of SLOS involves SMO dysregulation by altered sterol levels, but the salient sterol species has not been identified. Here, we clarify the relationship between disrupted cholesterol metabolism and reduced SHH signalling in SLOS by modelling the disorder in vitro. Our results indicate that a deficit in cholesterol, as opposed to an accumulation of 7DHC, impairs SMO activation and its localization to the primary cilium. PMID:26685159

  7. Hypersomnolence and reduced activity in pan-leptin receptor knockout mice

    PubMed Central

    Wang, Yuping; He, Junyun; Kastin, Abba J.; Hsuchou, Hung; Pan, Weihong

    2013-01-01

    Excessive obesity correlates with hypersomnolence and impaired cognitive function, presumably induced by metabolic factors and cytokines. Production of the adipokine leptin correlates with the amount of adiposity, and leptin has been shown to promote sleep. To determine whether leptin plays a major role in the hypersomnolence of obesity, we measured sleep architecture in pan-leptin receptor knockout (POKO) mice that do not respond to leptin because of the production of a mutant, non-signaling receptor. The obese POKO mice had more non-rapid eye movement (NREM) sleep and less waking time than their littermate controls. This was mainly seen during the light span, although increased bouts of rapid eye movement (REM) sleep were also seen in the dark span. The increase of NREM sleep correlated with the extent of obesity. The POKO mice also had decreased locomotor activity and more immobility in the open field test, but there was no increase of forced immobility nor reduction of sucrose intake as would be seen in depression. The increased NREM sleep and reduced locomotor activity in the POKO mice suggest that it was obesity, rather than leptin signaling, that played a predominant role in altering sleep architecture and activity. PMID:23955775

  8. Use of active barriers to reduce eutrophication problems in urban lakes.

    PubMed

    Hart, B; Roberts, S; James, R; Taylor, J; Donnert, D; Furrer, R

    2003-01-01

    Excessive concentration of phosphorus is one of the main causes of algal blooms and eutrophic conditions in lakes. In many urban lakes, it appears that a large proportion of the phosphorus in the water column comes from the sediments, particularly when these are anaerobic. Sub-aqueous capping is a relatively new method that has become an attractive option for isolating contaminated sediments from the environment, thus preventing or delaying the release of contaminants into surface waters. Active barrier materials (i.e. capping layers that consist of one or more reactive components) are gaining increasing attention for their greater efficiency in inactivating contaminants held in sediment layers. This paper reports laboratory bioreactor experiments to test the effectiveness of three forms of calcium carbonate (CaCO3) in reducing the release of phosphorus from anaerobic sediment from Lake Carramar, a small urban lake in Melbourne. Two of the CaCO3 active barrier materials tested proved to be quite effective, the most effective materials being the fine particle size, precipitated forms of CaCO3. Over the 20-day experimental period, a 2% layer of the German material SoCal reduced the amount of phosphorus released by almost 100 times over that occurring with no barrier. The Australian product ESCal, while not as effective as the SoCal, still reduced the phosphorus released by around 15 times that with no barrier. A finely ground Lilydale limestone was essentially ineffective in reducing phosphorus release from the sediments. A preliminary cost-benefit analysis suggests that SoCal is unlikely to be attractive for use in Australia, given the estimated application cost of around 3,800 dollars per tonne. However, although the ESCal is slightly less effective in retaining phosphorus, its potential application cost estimated at 2,000 dollars per tonne, makes it an attractive option. On the basis of these most promising preliminary results, we intend to further test the use of

  9. Wound healing and antibacterial activities of chondroitin sulfate- and acharan sulfate-reduced silver nanoparticles.

    PubMed

    Im, A-Rang; Kim, Jee Young; Kim, Hyun-Seok; Cho, Seonho; Park, Youmie; Kim, Yeong Shik

    2013-10-01

    For topical applications in wound healing, silver nanoparticles (AgNPs) have attracted much attention as antibacterial agents. Herein, we describe a green-synthetic route for the production of biocompatible and crystalline AgNPs using two glycosaminoglycans, chondroitin sulfate (CS) and acharan sulfate (AS), as reducing agents. The synthetic approach avoids the use of toxic chemicals, and the yield of AgNPs formation is found to be 98.1% and 91.1% for the chondroitin sulfate-reduced silver nanoparticles (CS-AgNPs) and the acharan sulfate-reduced silver nanoparticles (AS-AgNPs), respectively. Nanoparticles with mostly spherical and amorphous shapes were observed, with an average diameter of 6.16 ± 2.26 nm for CS-AgNPs and 5.79 ± 3.10 nm for AS-AgNPs. Images of the CS-AgNPs obtained from atomic force microscopy revealed the self-assembled structure of CS was similar to a densely packed woven mat with AgNPs sprinkled on the CS. These nanoparticles were stable under cell culture conditions without any noticeable aggregation. An approximately 128-fold enhancement of the antibacterial activities of the AgNPs was observed against Enterobacter cloacae and Escherichia coli when compared to CS and AS alone. In addition, an in vivo animal model of wound healing activity was tested using mice that were subjected to deep incision wounds. In comparison to the controls, the ointments containing CS-AgNPs and AS-AgNPs stimulated wound closure under histological examination and accelerated the deposition of granulation tissue and collagen in the wound area. The wound healing activity of the ointments containing CS-AgNPs and AS-AgNPs are comparable to that of a commercial formulation of silver sulfadiazine even though the newly prepared ointments contain a lower silver concentration. Therefore, the newly prepared AgNPs demonstrate potential for use as an attractive biocompatible nanocomposite for topical applications in the treatment of wounds. PMID:24008263

  10. Regulation of pyruvate dehydrogenase activity and citric acid cycle intermediates during high cardiac power generation

    PubMed Central

    Sharma, Naveen; Okere, Isidore C; Brunengraber, Daniel Z; McElfresh, Tracy A; King, Kristen L; Sterk, Joseph P; Huang, Hazel; Chandler, Margaret P; Stanley, William C

    2005-01-01

    A high rate of cardiac work increases citric acid cycle (CAC) turnover and flux through pyruvate dehydrogenase (PDH); however, the mechanisms for these effects are poorly understood. We tested the hypotheses that an increase in cardiac energy expenditure: (1) activates PDH and reduces the product/substrate ratios ([NADH]/[NAD+] and [acetyl-CoA]/[CoA-SH]); and (2) increases the content of CAC intermediates. Measurements were made in anaesthetized pigs under control conditions and during 15 min of a high cardiac workload induced by dobutamine (Dob). A third group was made hyperglycaemic (14 mm) to stimulate flux through PDH during the high work state (Dob + Glu). Glucose and fatty acid oxidation were measured with 14C-glucose and 3H-oleate. Compared with control, the high workload groups had a similar increase in myocardial oxygen consumption ( and cardiac power. Dob increased PDH activity and glucose oxidation above control, but did not reduce the [NADH]/[NAD+] and [acetyl-CoA]/[CoA-SH] ratios, and there were no differences between the Dob and Dob + Glu groups. An additional group was treated with Dob + Glu and oxfenicine (Oxf) to inhibit fatty acid oxidation: this increased [CoA-SH] and glucose oxidation compared with Dob; however, there was no further activation of PDH or decrease in the [NADH]/[NAD+] ratio. Content of the 4-carbon CAC intermediates succinate, fumarate and malate increased 3-fold with Dob, but there was no change in citrate content, and the Dob + Glu and Dob + Glu + Oxf groups were not different from Dob. In conclusion, compared with normal conditions, at high myocardial energy expenditure (1) the increase in flux through PDH is regulated by activation of the enzyme complex and continues to be partially controlled through inhibition by fatty acid oxidation, and (2) there is expansion of the CAC pool size at the level of 4-carbon intermediates that is largely independent of myocardial fatty acid oxidation. PMID:15550462

  11. Favorite Lesson Plans: Powerful Standards-Based Activities.

    ERIC Educational Resources Information Center

    Wilen, William W., Ed.

    This collection of lesson plans helps social studies teachers and teacher educators implement the various national and state standards in their classrooms. The collection illustrates how classroom implementation can be achieved through the application of the powerful teaching and learning principles devised by National Council for the Social…

  12. Reduced polarization decay due to carrier in-scattering in a semiconductor active medium

    SciTech Connect

    Hughes, S.; Knorr, A.; Koch, S.W.; Chow, W.W.

    1996-07-01

    The in-scattering processes, which reduce the decay of the active medium polarization, should be included in a consistent treatment of semiconductor laser gain. The in-scattering processes affect the laser gain by decreasing the influence of the high k-states, which contribute absorption to the spectrum. A theory, based on the semiconductor-Bloch equations with the effects of carrier-carrier scattering treated at the level of the quantum kinetic equations in the Markov limit, predicts gain spectra that do not exhibit absorption below the renormalized band gap, in agreement with experiment. When compared to gain calculations where the in-scattering contribution is neglected, the theory predicts markedly different properties for intrinsic laser parameters, such as peak gain, gain bandwidth, differential gain and carrier density at transparency, especially at low carrier densities.

  13. Tensile properties of reduced activation Fe-9Cr-2W steels after FFTF irradiation

    NASA Astrophysics Data System (ADS)

    Kurishita, H.; Kayano, H.; Narui, M.; Kimura, A.; Hamilton, M. L.; Gelles, D. S.

    1994-09-01

    In order to develop radiation resistant steels with reduced activation for fusion reactor applications, the effect of fast neutron irradiation was investigated on the tensile properties of five types of Fe-9Cr-2W martensitic steel with and without small additions of boron, yttrium and aluminum. Miniature tensile specimens of the steels were irradiated to 28 dpa at 663 K and 33-35 dpa at 703, 793 and 873 K in the Fast Flux Test Facility (FFTF) and were deformed at temperatures between 300 and 873 K. The yield and ultimate tensile stresses were not significantly affected by the irradiations, but the total elongation was considerably decreased by the irradiation at 663 K. The reduction in elongation depended strongly on the test temperature with a maximum at around 673 K. The addition of yttrium alone tended to increase the high temperature strength, while the simultaneous addition of yttrium and aluminum tended to decrease the total elongation.

  14. Effect of mechanical restraint on weldability of reduced activation ferritic/martensitic steel thick plates

    NASA Astrophysics Data System (ADS)

    Serizawa, Hisashi; Nakamura, Shinichiro; Tanaka, Manabu; Kawahito, Yousuke; Tanigawa, Hiroyasu; Katayama, Seiji

    2011-10-01

    As one of the reduced activation ferritic/martensitic steels, the weldability of thick F82H plate was experimentally examined using new heat sources in order to minimize the total heat input energy in comparison with TIG welding. A full penetration of 32 mm thick plate could be produced as a combination of a 12 mm deep first layer generated by a 10 kW fiber laser beam and upper layers deposited by a plasma MIG hybrid welding with Ar + 2%O shielding gas. Also, the effect of mechanical restraint on the weldability under EB welding of thick F82H plate was studied by using FEM to select an appropriate specimen size for the basic test. The appropriate and minimum size for the basic test of weldability under EB welding of 90 mm thick plate might be 200 mm in length and 400 mm in width where the welding length should be about 180 mm.

  15. Restricted mobility of specific functional groups reduces anti-cancer drug activity in healthy cells

    DOE PAGESBeta

    Martins, Murillo L.; Ignazzi, Rosanna; Eckert, Juergen; Watts, Benjamin; Kaneno, Ramon; Zambuzzi, Willian F.; Daemen, Luke; Saeki, Margarida J.; Bordallo, Heloisa N.

    2016-03-02

    Here, the most common cancer treatments currently available are radio- and chemo-therapy. These therapies have, however, drawbacks, such as, the reduction in quality of life and the low efficiency of radiotherapy in cases of multiple metastases. To lessen these effects, we have encapsulated an anti-cancer drug into a biocompatible matrix. In-vitro assays indicate that this bio-nanocomposite is able to interact and cause morphological changes in cancer cells. Meanwhile, no alterations were observed in monocytes and fibroblasts, indicating that this system might carry the drug in living organisms with reduced clearance rate and toxicity. X-rays and neutrons were used to investigatemore » the carrier structure, as well as to assess the drug mobility within the bio-nanocomposite. In conclusion, from these unique data we show that partial mobility restriction of active groups of the drug molecule suggests why this carrier design is potentially safer to healthy cells.« less

  16. Development of Reduced Activation Ferritic-Martensitic Steels and fabrication technologies for Indian test blanket module

    NASA Astrophysics Data System (ADS)

    Raj, Baldev; Jayakumar, T.

    2011-10-01

    For the development of Reduced Activation Ferritic-Martensitic Steel (RAFMS), for the Indian Test Blanket Module for ITER, a 3-phase programme has been adopted. The first phase consists of melting and detailed characterization of a laboratory scale heat conforming to Eurofer 97 composition, to demonstrate the capability of the Indian industry for producing fusion grade steel. In the second phase which is currently in progress, the chemical composition will be optimized with respect to tungsten and tantalum for better combination of mechanical properties. Characterization of the optimized commercial scale India-specific RAFM steel will be carried out in the third phase. The first phase of the programme has been successfully completed and the tensile, impact and creep properties are comparable with Eurofer 97. Laser and electron beam welding parameters have been optimized and welding consumables were developed for Narrow Gap - Gas Tungsten Arc welding and for laser-hybrid welding.

  17. Restricted mobility of specific functional groups reduces anti-cancer drug activity in healthy cells

    PubMed Central

    Martins, Murillo L.; Ignazzi, Rosanna; Eckert, Juergen; Watts, Benjamin; Kaneno, Ramon; Zambuzzi, Willian F.; Daemen, Luke; Saeki, Margarida J.; Bordallo, Heloisa N.

    2016-01-01

    The most common cancer treatments currently available are radio- and chemo-therapy. These therapies have, however, drawbacks, such as, the reduction in quality of life and the low efficiency of radiotherapy in cases of multiple metastases. To lessen these effects, we have encapsulated an anti-cancer drug into a biocompatible matrix. In-vitro assays indicate that this bio-nanocomposite is able to interact and cause morphological changes in cancer cells. Meanwhile, no alterations were observed in monocytes and fibroblasts, indicating that this system might carry the drug in living organisms with reduced clearance rate and toxicity. X-rays and neutrons were used to investigate the carrier structure, as well as to assess the drug mobility within the bio-nanocomposite. From these unique data we show that partial mobility restriction of active groups of the drug molecule suggests why this carrier design is potentially safer to healthy cells. PMID:26932808

  18. Hydrogen Embrittlement Susceptibility of Conventional and Reduced Activation 9Cr-Steels

    SciTech Connect

    Maday, Marie-Francoise

    2005-05-15

    Hydrogen embrittlement behaviour of the reduced activation ferritic/martensitic steels, Eurofer'97 and VS3104, has been compared to