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1

A reactant-product decoupling method for state-to-state reactive scattering  

SciTech Connect

We propose a general and computationally attractive method that decouples the reactant from the product for state-to-state dynamics calculation in quantum reactive scattering with multiproduct arrangements. In this decoupled approach, the full wave function is divided into the reactant and product components that are connected through absorbing potentials. Using this method, the overall computational effort for state-to-state calculation is essentially the sum of those for the reactant and product arrangements separately. This method solves, to a large extent, the notorious problem of the choice of coordinates in quantum reactive scattering. Although the application of this decoupling method is specifically presented for time-dependent implementation in this communication, the basic methodology should also be applicable in the time-independent application as well. {copyright} {ital 1996 American Institute of Physics.}

Peng, T.; Zhang, J.Z. [Department of Chemistry, New York University, New York, New York 10003 (United States)

1996-10-01

2

Reactive scattering of F+HD -> HF(v,J)+D: HF(v,J) nascent product state distributions and evidence for quantum transition state resonances  

Microsoft Academic Search

Single collision reactive scattering dynamics of F+ HDHF(v,J)+ D have been investigated exploiting high-resolution (0.0001 cm?1) infrared laser absorption for quantum state resolved detection of nascent HF(v,J) product states. State resolved Doppler profiles are recorded for a series of HF rovibrational transitions and converted into state resolved fluxes via density-to-flux analysis, yielding cross-section data for relative formation of HF(v,J) at

Warren W. Harper; Sergey A. Nizkorodov; David Nesbitt

2001-01-01

3

Quantum reactive scattering on innovative computing platforms  

NASA Astrophysics Data System (ADS)

The possibility of implementing quantum reactive scattering programs on cheap platforms, originally used for graphic purposes only, has been investigated using a NVIDIA GPU. After a conversion of the code considered from Fortran to C and its deep restructuring for exploiting the GPU key features, significant speedups have been obtained for RWAVEPR, a time dependent quantum reactive scattering code propagating in time a complex wavepacket. As benchmark calculations those concerned with the evaluation of the reactive probabilities of the Cl+H2 and the N+N2 reactions have been considered.

Pacifici, Leonardo; Nalli, Danilo; Laganà, Antonio

2013-05-01

4

A Chebyshev method for state-to-state reactive scattering using reactant-product decoupling: OH + H2 --> H2O + H  

NASA Astrophysics Data System (ADS)

We extend a recently developed wave packet method for computing the state-to-state quantum dynamics of AB + CD --> ABC + D reactions [M. T. Cvitaš and S. C. Althorpe, J. Phys. Chem. A 113, 4557 (2009)] to include the Chebyshev propagator. The method uses the further partitioned approach to reactant-product decoupling, which uses artificial decoupling potentials to partition the coordinate space of the reaction into separate reactant, product, and transition-state regions. Separate coordinates and basis sets can then be used that are best adapted to each region. We derive improved Chebyshev partitioning formulas which include Mandelshtam-and-Taylor-type decoupling potentials, and which are essential for the non-unitary discrete variable representations that must be used in 4-atom reactive scattering calculations. Numerical tests on the fully dimensional OH + H2 --> H2O + H reaction for J = 0 show that the new version of the method is as efficient as the previously developed split-operator version. The advantages of the Chebyshev propagator (most notably the ease of parallelization for J > 0) can now be fully exploited in state-to-state reactive scattering calculations on 4-atom reactions.

Cvitaš, Marko T.; Althorpe, Stuart C.

2013-08-01

5

Production of a biomimetic Fe(I)-S phase on pyrite by atomic hydrogen beam surface reactive scattering.  

PubMed

Molecular beam surface scattering and X-ray absorption spectroscopic experiments were employed to study the reaction of deuterium atoms with a pyrite, FeS(2) (100), surface and to investigate the electronic and geometric structures of the resulting Fe-S phases. Incident D atoms, produced by a radiofrequency plasma and expanded in an effusive beam, were directed at a pyrite surface held at various temperatures from ambient up to 200 °C. During exposure to the D-atom beam, D(2)S products were released with a thermal distribution of molecular speeds, indicating that the D atoms likely reacted in thermal equilibrium with the surface. The yield of D(2)S from the surface decreased approximately exponentially with exposure duration, suggesting that the surface accessible sulfur atoms were depleted, thus leaving an iron-rich surface. This conclusion is consistent with X-ray absorption measurements of the exposed surfaces, which indicated the formation of a layered structure, with elemental iron as the outermost layer on top of a formally Fe((I))-S phase as an intermediate layer and a formally Fe((II))-S(2) bulk pyrite layer at lower depths. The reduced Fe((I))-S phase is particularly remarkable because of its similarity to the catalytically active sites of small molecule metalloenzymes, such as FeFe-hydrogenases and MoFe-nitrogenases. PMID:21526811

Che, Li; Gardenghi, David J; Szilagyi, Robert K; Minton, Timothy K

2011-04-28

6

Reactive scattering of F+HD -> HF(v,J)+D: HF(v,J) nascent product state distributions and evidence for quantum transition state resonances  

SciTech Connect

Single collision reactive scattering dynamics of F+ HDHF(v,J)+ D have been investigated exploiting high-resolution (0.0001 cm?1) infrared laser absorption for quantum state resolved detection of nascent HF(v,J) product states. State resolved Doppler profiles are recorded for a series of HF rovibrational transitions and converted into state resolved fluxes via density-to-flux analysis, yielding cross-section data for relative formation of HF(v,J) at Ecom0.6(2), 1.0(3), 1.5(3), and 1.9(4) kcal/mol. State resolved HF(v,J) products at all but the lowest collision energy exhibit Boltzmann-type populations, characteristic of direct reactive scattering dynamics. At the lowest collision energy[Ecom0.6(2) kcal/mol], however, the HF(v= 2,J) populations behave quite anomalously, exhibiting a nearly''flat'' distribution out to J11 before dropping rapidly to zero at the energetic limit. These results provide strong experimental support for quantum transition state resonance dynamics near Ecom0.6 kcal /mol corresponding classically to H atom chattering between the F and D atoms, and prove to be in remarkably quantitative agreement with theoretical wave packet predictions by Skodje et al.[J. Chem. Phys. 112, 4536 (2000)]. These fully quantum state resolved studies therefore nicely complement the recent crossed beam studies of Dong et al.[J. Chem. Phys. 113, 3633 (2000)], which confirm the presence of this resonance via angle resolved differential cross-section measurements. The observed quantum state distributions near threshold also indicate several rotational states in the HF(v= 3) vibrational manifold energetically inaccessible to F(2P3/2) reagent, but which are consistent with a minor (5%) nonadiabatic contribution from spin?orbit excited F*(2P1/2).?2002 American Institute of Physics.

Harper, Warren W. (BATTELLE (PACIFIC NW LAB)); Nizkorodov, Sergey A. (California Institute of Technology); Nesbitt, David (Colorado, University Of)

2001-12-01

7

Further partitioning of the reactant-product decoupling equations of state-to-state reactive scattering and their solution by the time-independent wave-packet method  

SciTech Connect

The reactant-product decoupling (RPD) equations are a rigorous formulation of state-to-state reactive scattering recently introduced by Peng and Zhang. For an N-arrangement reaction there are a total of N RPD equations, each of which describes the dynamics in just one region of coordinate space. One of the regions (the r-region) encloses the reactant channel and the strong interaction region; each of the other N{minus}1 regions encloses one of the product channels. In this paper we develop a suggestion later made by Kouri and co-workers: that the original RPD equations can be further partitioned into a set of new RPD equations, in which the original r-region is now partitioned into three regions{emdash}two enclosing the reactant channel, and one enclosing the strong interaction region. After introducing the new RPD equations, we derive the time-independent wave-packet (TIW) form of the equations, and show how to solve them using an extended version of the Chebyshev propagator. We test the new RPD equations (and the method) by calculating state-to-state reaction probabilities and inelastic probabilities for the three-dimensional (J=0) H+H{sub 2} reaction. {copyright} {ital 1997 American Institute of Physics.}

Althorpe, S.C.; Kouri, D.J. [Department of Chemistry and Department of Physics, University of Houston, Houston, Texas 77204-5641 (United States); Hoffman, D.K. [Department of Chemistry and Ames Laboratory, Iowa State University, Ames, Iowa 50011 (United States)

1997-11-01

8

Reactant-product decoupling method for state-to-state reactive scattering: A case study for 3D H+H{sub 2} exchange reaction (J=0)  

SciTech Connect

In this paper, we present theoretical and computational details of implementing the recently developed reactant-product decoupling (RPD) method (J. Chem. Phys. {bold 105}, 6072 (1996)) for state-to-state quantum reactive scattering calculations of the prototypical H + H{sub 2} reaction in three dimensions. The main purpose of this paper is to explore important features of the RPD scheme for use as a general and efficient computational approach to study state-to-state quantum dynamics for polyatomic reactions by using 3D H + H{sub 2} as an example. Specific computational techniques and numerical details are explicitly provided for efficient application of this method in the time-dependent (TD) implementation. Using the RPD method, the calculated state-to-state reaction probabilities for the 3D H + H{sub 2} reaction are in excellent agreement with those from the time-independent variational calculations, and the computational cost of the RPD method is significantly lower than other existing TD methods for state-to-state dynamics calculations. {copyright} {ital 1997 American Institute of Physics.}

Zhu, W.; Peng, T.; Zhang, J.Z. [Department of Chemistry, New York University, New York, New York 10003 (United States)

1997-02-01

9

Surface enhanced Raman scattering based sensitive detection of histone demethylase activity using a formaldehyde-selective reactive probe.  

PubMed

A novel surface enhanced Raman scattering (SERS) based assay using a formaldehyde-selective reactive probe for sensitive detection of activity of histone demethylases (HDMs) by direct observation of by-product formaldehyde was reported. PMID:23938472

Wang, Yu; Deng, Xianghua; Liu, Jinwen; Tang, Hao; Jiang, Jianhui

2013-10-01

10

Photodissociation of Oriented Molecule Beams and Reactive Scattering  

NASA Astrophysics Data System (ADS)

The requirement of proper mutual orientation of reagents is second only to the energy requirement for chemical reaction to take place. Since the introduction of hexapole field focusing and orientation of symmetric-top molecule in 1965, considerable insight has been gained on the role of orientation in reactive scattering dynamics. To achieve a more quantitative understanding of the steric effect in reactive scattering, a pulsed supersonic molecular beam machine with a 3-meter long, electrostatic hexapole field has been constructed. Focusing and rotational state selection has been achieved for prolate symmetric-top molecules, such as CH_3X (X = F, Cl, Br and I). Partial state selection has been achieved for oblate symmetric-top molecules. Various polar asymmetric top molecules have also been focused, as well as the pseudo -symmetric tops, (CH_3)_3 CI and (CH_3)_3 CBr. These molecules have been studied in some detail. They have been focused and oriented with a homogeneous field. The degree of laboratory orientation has been measured for the first time with a newly developed polarized laser photofragmentation technique. It is found that the goodness of orientation achievable has the following sequence: (CH_3 )_3CBr > (CH_3)_3CI > CH_3I. Various techniques of producing reactive atomic beams have been explored and tested, including a seeded supersonic nozzle metal beam source, a seeded laser evaporation metal beam source, a Cl atom source utilizing microwave discharge, and an effusive metal beam oven. The effusive oven of Sr produces very stable beams and has therefore been used in a study of the crossed beam reaction of Sr + CH_3I. In order to detect weak product signal (SrI) from the crossed-beam reaction, a sensitive detection technique has been developed utilizing single photon ionization of SrI with 193 nm excimer laser radiation and time-of-flight mass spectrometry. The SrI^{+} signal is readily detected. The much stronger Sr^{+} ion beam (from the photoionization of the Sr reagent) is deflected by a gated high voltage pulse. By changing the carrier gas of the seeded, pulsed CH_3I beam to achieve different collision energies, the excitation function of Sr + CH_3I reaction has been measured. The reaction threshold is estimated to be 0.07 +/- 0.02 eV, in accord with expectation based on analogous reactions and semi -empirical theory.

Xu, Qixun

11

Light Scattering from a Chemically Reactive Fluid. I. Spectral Distribution  

Microsoft Academic Search

The spectral distribution of light scattered by fluctuations about equilibrium in a chemically reactive fluid is calculated from the time dependence of the fluctuations predicted by the linearized hydrodynamic equations of irreversible thermodynamics. The theory treats a system with an arbitrary number, n, of independent chemical reactions which are coupled to the hydrodynamic processes involving viscosity and thermal conductivity. However,

L. Blum; Z. W. Salsburg

1968-01-01

12

Modern Integral Equation Techniques for Quantum Reactive Scattering Theory  

Microsoft Academic Search

Rigorous calculations of cross sections and rate constants for elementary gas phase chemical reactions are performed for comparison with experiment, to ensure that our picture of the chemical reaction is complete. We focus on the H\\/D + H_2 to H _2\\/DH + H reaction, and use the time independent integral equation technique in quantum reactive scattering theory. We examine the

Scott Michael Auerbach

1993-01-01

13

Reactive scattering of electronically excited alkali atoms with molecules  

SciTech Connect

Representative families of excited alkali atom reactions have been studied using a crossed beam apparatus. For those alkali-molecule systems in which reactions are also known for ground state alkali and involve an early electron transfer step, no large differences are observed in the reactivity as Na is excited. More interesting are the reactions with hydrogen halides (HCl): it was found that adding electronic energy into Na changes the reaction mechanism. Early electron transfer is responsible of Na(5S, 4D) reactions, but not of Na(3P) reactions. Moreover, the NaCl product scattering is dominated by the HCl/sup -/ repulsion in Na(5S, 4D) reactions, and by the NaCl-H repulsion in the case of Na(3P). The reaction of Na with O/sub 2/ is of particular interest since it was found to be state specific. Only Na(4D) reacts, and the reaction requires restrictive constraints on the impact parameter and the reactants' relative orientation. The reaction with NO/sub 2/ is even more complex since Na(4D) leads to the formation of NaO by two different pathways. It must be mentioned however, that the identification of NaO as product in these reactions has yet to be confirmed.

Mestdagh, J.M.; Balko, B.A.; Covinsky, M.H.; Weiss, P.S.; Vernon, M.F.; Schmidt, H.; Lee, Y.T.

1987-06-01

14

Classical path method in inelastic and reactive scattering  

Microsoft Academic Search

The semiclassical (classical path) method has over the years probably been the most commonly used approximate method for describing many molecular dynamical processes in inelastic, non-adiabatic and recently also in reactive scattering. Here an overview of the development of the theory is given. Its connection to various other approximate dynamic theories such as the eikonal, time-dependent self-consistent field, Gaussian wave

Gert D. Billing

1994-01-01

15

Reactive scattering of a supersonic fluorine atom beam: F I2  

NASA Astrophysics Data System (ADS)

Reactive scattering of F atoms with I2 molecules has been studied at an initial translational energy E ˜ 20 kJ mol-1 using a supersonic beam of F atoms seeded in Ne buffer gas. The differential reaction cross section is found to be almost symmetrical about centre-of-mass scattering angle ? = 90° but with a minor additional component to the scattering in the forward hemisphere with very low product translational energy. Kinematic analysis of previous measurements at an initial translational energy E ˜ 40 kJ mol-1 using a supersonic beam of F atoms seeded in He buffer gas has been refined and shows increased scattering which is peaked quite sharply in the backward direction. These features are in accord with the predictions of a recent quasiclassical trajectory study which shows that migratory dynamics are followed by approximately half of all reactive trajectories with scattering favouring the backward hemisphere while nonmigratory trajectories favour scattering into the forward hemisphere. Migratory trajectories are promoted by the accessibility of a second potential energy well in the IFI configuration in addition to the well in the FII configuration which is accessed initially on the F + I2 potential energy surface. The F + I2 reactive scattering is similar to that of O + I2 which suggests that migratory trajectories may also occur for the O + I2 reaction with access to a well in the IOI configuration on the singlet potential energy surface following initial access of reactants to a well in the OII configuration on the triplet potential energy surface.

Firth, N. C.; Keane, N. W.; Smith, D. J.; Grice, R.

16

BIODIESEL PRODUCTION BY REACTIVE DISTILLATION  

Microsoft Academic Search

Fossil fuels demand to meet energy requirements, is increasing every day and oil reserves are reducing dramatically. For this reason, the production of renewable fuels has acquired great importance in the last years in order to satisfy these energy necessities. The biodiesel makes part of this kind of fuels. However, currently there are problems in its separation and purification. Therefore,

17

Approximate Quantum Mechanical Calculation of Reactive Scattering Cross Sections - The Fixed Angle Reactor Model (FARM)  

NASA Astrophysics Data System (ADS)

An approximate three-dimensional quantum mechanical method for the calculation of atom-diatom reactive scattering cross sections and rate constants is described. The method is known as the Fixed Angle Reactor Model (FARM). Its key features are that it uses information from both classical trajectory and simplified quantum mechanical calculations to compute vibrational state-to-state reactive scattering cross sections. The classical trajectory calculations are used to estimate the degree to which torques acting during the approach of the collision partners are able to successfully reorient them into the most favorable geometry for subsequent reaction. This information is then used, together with fixed angle quantum reactive scattering calculations to approximate a full three-dimensional quantum reactive scattering calculation. Test results are presented for the reactions: H + H2(? = 0) ? H2(?' = 0) + H and D + H2(? = 1) ? HD + H and comparison is made with other methods.

Balint-Kurti, G. G.; de Haar, B. M. D. D. Jansen op

1988-01-01

18

Inelastic and Reactive Scattering Dynamics of Hyperthermal Oxygen Atoms on Ionic Liquid Surfaces: [emim][NTf{sub 2}] and [C{sub 12}mim][NTf{sub 2}  

SciTech Connect

Collisions of hyperthermal oxygen atoms, with an average translational energy of 520 kJ mol{sup -1}, on continuously refreshed ionic liquids, 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl) imide ([emim][NTf{sub 2}]) and 1-dodecyl-3-methylimidazolium bis(trifluoromethylsulfonyl) imide ([C{sub 12}mim][NTf{sub 2}]), were studied with the use of a beam-surface scattering technique. Time-of-flight and angular distributions of inelastically scattered O and reactively scattered OH and H{sub 2}O were collected for various angles of incidence with the use of a rotatable mass spectrometer detector. For both O and OH, two distinct scattering processes were identified, which can be empirically categorized as thermal and non-thermal. Non-thermal scattering is more probable for both O and OH products. The observation of OH confirms that at least some reactive sites, presumably alkyl groups, must be exposed at the surface. The ionic liquid with the longer alkyl chain, [C{sub 12}mim][NTf{sub 2}], is substantially more reactive than the liquid with the shorter alkyl chain, [emim][NTf{sub 2}], and proportionately much more so than would be predicted simply from stoichiometry based on the number of abstractable hydrogen atoms. Molecular dynamics models of these surfaces shed light on this change in reactivity. The scattering behavior of O is distinctly different from that of OH. However, no such differences between inelastic and reactive scattering dynamics have been seen in previous work on pure hydrocarbon liquids, in particular the benchmark, partially branched hydrocarbon, squalane (C{sub 30}H{sub 62}). The comparison between inelastic and reactive scattering dynamics indicates that inelastic scattering from the ionic liquid surfaces takes place predominantly at non-reactive sites that are effectively stiffer than the reactive alkyl chains, with a higher proportion of collisions sampling such sites for [emim][NTf{sub 2}] than for [C{sub 12}mim][NTf{sub 2}].

Wu Bohan; Zhang Jianming; Minton, Timothy K. [Department of Chemistry and Biochemistry, Montana State University, Bozeman, MT 59717 (United States); McKendrick, Kenneth G. [School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh EH14 4AS (United Kingdom); Slattery, John M. [Department of Chemistry, University of York, Heslington, York YO10 5DD (United Kingdom); Yockel, Scott; Schatz, George C. [Department of Chemistry, Northwestern University, Evanston, Illinois 60208-3113 (United States)

2011-05-20

19

Single ? production in neutrino-nucleus scattering  

NASA Astrophysics Data System (ADS)

We study 1? production in both charged and neutral current neutrino-nucleus scattering for neutrino energies below 2 GeV. We use a theoretical model for one pion production at the nucleon level that we correct for medium effects. The results are incorporated into a cascade program that apart from production also includes the pion final state interaction inside the nucleus. Besides, in some specific channels coherent ? production is also possible and we evaluate its contribution as well. Our results for total and differential cross sections are compared with recent data from the MiniBooNE Collaboration. The model provides an overall acceptable description of the data, better for neutral-current than for charged-current channels, although the theory is systematically below the data. Differential cross sections, folded with the full neutrino flux, show that most of the missing pions lie in the forward direction and at high energies.

Hernández, E.; Nieves, J.; Vacas, M. J. Vicente

2013-06-01

20

Entanglement of Quasielastic Scattering and Pion Production  

SciTech Connect

The extraction of neutrino oscillation parameters requires the determination of the neutrino energy from observations of the hadronic final state. Here we discuss the difficulties connected with this energy reconstruction for the ongoing experiments MiniBooNE and T2K. We point out that a lower limit to the uncertainty in the reconstructed energy from Fermi motion alone amounts to about 15%. The entanglement of very different elementary processes, in this case quasielastic scattering and pion production, in the actual observables leads to considerably larger errors. We discuss the sensitivity of the energy reconstruction to detection techniques and experimental acceptances. We also calculate the misidentification cross section for electron appearance in the T2K experiment due to neutral pion production.

Mosel, Ulrich; Lalakulich, Olga; Leitner, Tina [Institut fuer Theoretische Physik, Universitaet Giessen, D-35392 Giessen (Germany)

2011-11-23

21

Quantum reactive scattering of ultracold NH(X (3)?(-)) radicals in a magnetic trap.  

PubMed

We investigate the ultracold reaction dynamics of magnetically trapped NH(X (3)?(-)) radicals using rigorous quantum scattering calculations involving three coupled potential energy surfaces. We find that the reactive NH+NH cross section is driven by a short-ranged collisional mechanism, and its magnitude is only weakly dependent on magnetic field strength. Unlike most ultracold reactions observed so far, the NH+NH scattering dynamics is nonuniversal. Our results indicate that chemical reactions can cause more trap loss than spin-inelastic NH+NH collisions, making molecular evaporative cooling more difficult than previously anticipated. PMID:23432241

Janssen, Liesbeth M C; van der Avoird, Ad; Groenenboom, Gerrit C

2013-02-04

22

Production of reactive sintered nickel aluminide  

SciTech Connect

This is the final report pertaining to the development of aluminides by reactive synthesis. Included in this report is an overview of results during the scope of this effort, details on specific task accomplishments, and a summary of customer evaluations. Opportunities for future work are also included at the end of this report.

NONE

1995-10-01

23

Production of Reactive Oxygen Species by Polyhalogenated Cyclic Hydrocarbons (PCH).  

National Technical Information Service (NTIS)

The results of this research strongly support the hypothesis that polyhalogenated cyclic hydrocarbons (PCH) induce production of reactive oxygen species which may contribute to many of the toxic manifestations associated with these xenobiotics. A non-inva...

S. J. Stohs

1992-01-01

24

Production and Consumption of Reactive Oxygen Species by Fullerenes  

EPA Science Inventory

Reactive oxygen species (ROS) are one of the most important intermediates in chemical, photochemical, and biological processes. To understand the environmental exposure and toxicity of fullerenes better, the production and consumption of ROS (singlet oxygen, superoxide, hydrogen ...

25

MODELLING OF REACTIVE DISTILLATION - PROPYLENE OXIDE PRODUCTION  

Microsoft Academic Search

Selectivity and equilibrium of chemical reactions can be significantly influenced by the distillation of one or more products from the reaction mixture. Simultaneous reaction and separation of the desired product is very important in the case of consecutive reactions. Simulation of the reactor for propylene oxide (POX) synthesis from propylenechlorohydrine (PCH) and calcium hydroxide is presented in the paper. The

M. Kotora; Z. Švandová

2005-01-01

26

Coherent Control of Reactive Scattering: Li+HF and F+HD  

NASA Astrophysics Data System (ADS)

The principle of Coherent Control (CC)(P. Brumer and M. Shapiro, Sci. Am. 272) 56 (March 1995). M. Shapiro and P. Brumer, J. Chem. Soc. Faraday Trans. 93 1263 (1997); Adv. Atom Mol. Opt. Phys. 42 287 (2000). has recently been extended to bimolecular reactive scattering( M. Shapiro and P. Brumer, Phys. Rev. Lett. 77) 2574 (1996) and applied to three dimensional calculations of the isotopic variants of H+H_2(A. Abrashkevich, M. Shapiro and P. Brumer, Phys. Rev. Lett. 81) 3789 (1998); erratum 82 3002 (1999); Chem. Phys. (in press).. We have used a contracted-basis log-derivative version of the Kohn variational principle(D.E. Manolopoulos, M. D'Mello and R.E. Wyatt, J. Chem. Phys. 93) 403 (1990). to apply the CC method to the following two reactions: 1. Li+HF. For this computationally intensive calculation we test the validity of the centrifugal sudden approximation; 2. F+HD. This reaction exhibits a reactive scattering resonance in only one of the two reactive channels. We examine the extent to which the formation of intermediate resonant states can be controlled.

Zeman, Vlado; Brumer, Paul; Shapiro, Moshe

2001-05-01

27

Tobacco smoke is a source of toxic reactive glycation products  

PubMed Central

Smokers have a significantly higher risk for developing coronary and cerebrovascular disease than nonsmokers. Advanced glycation end products (AGEs) are reactive, cross-linking moieties that form from the reaction of reducing sugars and the amino groups of proteins, lipids, and nucleic acids. AGEs circulate in high concentrations in the plasma of patients with diabetes or renal insufficiency and have been linked to the accelerated vasculopathy seen in patients with these diseases. Because the curing of tobacco takes place under conditions that could lead to the formation of glycation products, we examined whether tobacco and tobacco smoke could generate these reactive species that would increase AGE formation in vivo. Our findings show that reactive glycation products are present in aqueous extracts of tobacco and in tobacco smoke in a form that can rapidly react with proteins to form AGEs. This reaction can be inhibited by aminoguanidine, a known inhibitor of AGE formation. We have named these glycation products “glycotoxins.” Like other known reducing sugars and reactive glycation products, glycotoxins form smoke, react with protein, exhibit a specific fluorescence when cross-linked to proteins, and are mutagenic. Glycotoxins are transferred to the serum proteins of human smokers. AGE-apolipoprotein B and serum AGE levels in cigarette smokers were significantly higher than those in nonsmokers. These results suggest that increased glycotoxin exposure may contribute to the increased incidence of atherosclerosis and high prevalence of cancer in smokers.

Cerami, Carla; Founds, Hank; Nicholl, Iain; Mitsuhashi, Tomoko; Giordano, Donna; Vanpatten, Sonya; Lee, Annette; Al-Abed, Yousef; Vlassara, Helen; Bucala, Richard; Cerami, Anthony

1997-01-01

28

Production of reactive sintered nickel aluminide  

SciTech Connect

Effort over the past 3 months was directed at increasing manufacturing capacity (ball milling) and improving product quality. Orders for the powder have increased, mainly for plasma spray powders. NiAl is an excellent coat between a metal and a ceramic, and its use instead of cobalt should extending operating range for carbide tools. The feather phase in the sintered Ni[sub 3]Al was identified to be a Ni-rich phase nucleated on the grain boundaries with 10 wt % Al composition. The ductile to brittle temperature of powder extruded NiAl was found to be between 500 and 600 C, and shows a 50% elongation at 600 C.

Cooper, R.M.

1993-01-01

29

Stripping and complex formation in the reactive scattering of Cs/sup +/ ions with benzyl chloride  

SciTech Connect

The reaction of Cs/sup +/ with benzyl chloride, Cs/sup +/+BzCl..-->..CsCl+Bz/sup +/ in crossed molecular beams is reported. The reaction seems to occur along an attractive potential energy surface yielding forward scattering products. (AIP)

Horvat, R.C.; Safron, S.A.

1980-02-15

30

Production of n-Propyl Acetate by Reactive Distillation  

Microsoft Academic Search

First steps of the development of a catalytic reactive distillation process for the production of n-propyl acetate based on experiments and simulations are proposed. The kinetics for homogeneously (sulphuric acid) and heterogeneously (Amberlyst 15) catalysed reaction were investigated and the constants for a pseudo-homogeneous model are presented. Pilot plant experiments were performed using a homogeneous strong acid catalyst in a

M. Brehelin; F. Forner; D. Rouzineau; J.-U. Repke; X. Meyer; M. Meyer; G. Wozny

2007-01-01

31

Quantum mechanical reactive scattering theory for simple chemical reactions: Recent developments in methodology and applications  

SciTech Connect

It has recently been discovered that the S-matrix version of the Kohn variational principle is free of the Kohn anomalies'' that have plagued other versions and prevented its general use. This has made a major contribution to heavy particle reactive (and also to electron-atom/molecule) scattering which involve non-local (i.e., exchange) interactions that prevent solution of the coupled channel equations by propagation methods. This paper reviews the methodology briefly and presents a sample of integral and differential cross sections that have been obtained for the H + H{sub 2} {yields} H{sub 2} +H and D + H{sub 2} {yields} HD + H reactions in the high energy region (up to 1.2 eV translational energy) relevant to resonance structures reported in recent experiments. 35 refs., 11 figs.

Miller, W.H.

1989-08-01

32

Regulation of scatter factor production via a soluble inducing factor  

Microsoft Academic Search

Scatter factor (SF) (also known as hepato- cyte growth factor (HGF)) is a fibroblast-derived cytokine that stimulates motility, proliferation, and morphogenesis of epithelia. SF may play major roles in development, repair, and carcinogenesis. However, the physiologic signals that regulate its production are not well delineated. We found that various human tu- mor cell lines that do not produce SF secrete

Eliot M. Rosen; Ansamma Joseph; Liang Jin; Sara Rockwell; Jack A. Elias; Jaromir Knesel; James Wines; Jennifer McClellan; M. J. Kluger; Itzhak D. Goldberg; Ralph Zitnik

1994-01-01

33

Selectron Pair Production in E-E- Scattering  

NASA Astrophysics Data System (ADS)

We investigate pair production of selectrons in e-e- scattering with subsequent decay into an electron and the LSP including ISR and beamstrahlung. This process can be used at a linear collider to measure the selectron masses and the gaugino mass parameter M1 very precisely.

Blöchinger, C.; Fraas, H.; Mayer, T.

2002-03-01

34

D ? production in deep inelastic scattering at HERA  

Microsoft Academic Search

This paper presents measurements of D?± production in deep inelastic scattering from collisions between 27.5 GeV positrons and 820 GeV protons. The data have been taken with the ZEUS detector at HERA. The decay channel D?+ ? (D0 ? K??+)?+ (+c.c) has been used in the study. The e+p cross section for inclusive D?± production with 5 < Q2 <

S. Bhadra; W. R. Frisken; M. Khakzad; W. B. Schmidke; D. Mikunas; B. Musgrave; J. Repond; R. Stanek; R. L. Talaga; R. Yoshida; H. Zhang; M. C. K. Mattingly; F. Anselmo; P. Antonioli; G. Bari; M. Basile; L. Bellagamba; D. Boscherini; A. Bruni; G. Bruni; G. Cara Romeo; G. Castellini; L. Cifarelli; F. Cindolo; A. Contin; M. Corradi; S. de Pasquale; I. Gialas; P. Giusti; G. Iacobucci; G. Laurenti; G. Levi; A. Margotti; T. Massam; R. Nania; F. Palmonari; A. Pesci; A. Polini; G. Sartorelli; Y. Zamora Garcia; A. Zichichi; C. Amelung; A. Bornheim; I. Brock; K. Coböken; J. Crittenden; R. Deffner; M. Eckert; L. Feld; M. Grothe; H. Hartmann; K. Heinloth; L. Heinz; E. Hilger; H.-P. Jakob; U. F. Katz; E. Paul; M. Pfeiffer; Ch. Rembser; J. Stamm; R. Wedemeyer; D. S. Bailey; S. Campbell-Robson; W. N. Cottingham; B. Foster; R. Hall-Wilton; M. E. Hayes; G. P. Heath; H. F. Heath; D. Piccioni; D. G. Roff; R. J. Tapper; M. Arneodo; R. Ayad; M. Capua; A. Garfagnini; L. Iannotti; M. Schioppa; G. Susinno; J. Y. Kim; J. H. Lee; I. T. Lim; M. Y. Pac; A. Caldwell; N. Cartiglia; Z. Jing; W. Liu; J. A. Parsons; S. Ritz; S. Sampson; F. Sciulli; P. B. Straub; Q. Zhu; P. Borzemski; J. Chwastowski; A. Eskreys; Z. Jakubowski; M. B. Przybycien; M. Zachara; L. Zawiejski; L. Adamczyk; B. Bednarek; K. Jelen; D. Kisielewska; T. Kowalski; E. Rulikowska-Zarebska; L. Suszycki; J. Zajac; Z. Dulinski; A. Kotanski; G. Abbiendi; L. A. T. Bauerdick; U. Behrens; H. Beier; J. K. Bienlein; G. Cases; O. Deppe; K. Desler; G. Drews; U. Fricke; D. J. Gilkinson; C. Glasman; P. Göttlicher; J. Große-Knetter; T. Haas; W. Hain; D. Hasell; K. F. Johnson; M. Kasemann; W. Koch; U. Kötz; H. Kowalski; J. Labs; L. Lindemann; B. Löhr; M. Löwe; O. Manczak; J. Milewski; T. Monteiro; J. S. T. Ng; D. Notz; K. Ohrenberg; I. H. Park; A. Pellegrino; F. Pelucchi; K. Piotrzkowski; M. Roco; M. Rohde; J. Roldán; J. J. Ryan; A. A. Savin; U. Schneekloth; F. Selonke; B. Surrow; E. Tassi; T. Voß; D. Westphal; G. Wolf; U. Wollmer; C. Youngman; A. F. Zarnecki; W. Zeuner; B. D. Burow; H. J. Grabosch; A. Meyer; S. Schlenstedt; G. Barbagli; E. Gallo; P. Pelfer; G. Maccarrone; L. Votano; A. Bamberger; S. Eisenhardt; P. Markun; T. Trefzger; S. Wölfle; J. T. Bromley; N. H. Brook; P. J. Bussey; A. T. Doyle; D. H. Saxon; L. E. Sinclair; E. Strickland; M. L. Utley; R. Waugh; A. S. Wilson; I. Bohnet; N. Gendner; U. Holm; A. Meyer-Larsen; H. Salehi; K. Wick; L. K. Gladilin; D. Horstmann; D. Kçira; R. Klanner; E. Lohrmann; G. Poelz; W. Schott; F. Zetsche; T. C. Bacon; I. Butterworth; J. E. Cole; V. L. Harris; G. Howell; B. H. Y. Hung; L. Lamberti; K. R. Long; D. B. Miller; N. Pavel; A. Prinias; J. K. Sedgbeer; D. Sideris; A. F. Whitfield; U. Mallik; S. M. Wang; J. T. Wu; P. Cloth; D. Filges; J. I. Fleck; T. Ishii; M. Kuze; M. Nakao; K. Tokushuku; S. Yamada; Y. Yamazaki; S. H. An; S. B. Lee; S. W. Nam; H. S. Park; S. K. Park; F. Barreiro; J. P. Fernández; G. García; R. Graciani; J. M. Hernández; L. Hervás; L. Labarga; M. Martínez; J. del Peso; J. Puga; J. Terrón; J. F. de Trocóniz; F. Corriveau; D. S. Hanna; J. Hartmann; L. W. Hung; J. N. Lim; W. N. Murray; A. Ochs; M. Riveline; D. G. Stairs; M. St-Laurent; R. Ullmann; T. Tsurugai; V. Bashkirov; B. A. Dolgoshein; A. Stifutkin; G. L. Bashindzhagyan; P. F. Ermolov; Yu. A. Golubkov; L. A. Khein; N. A. Korotkova; I. A. Korzhavina; V. A. Kuzmin; O. Yu. Lukina; A. S. Proskuryakov; L. M. Shcheglova; A. V. Shumilin; A. N. Solomin; S. A. Zotkin; C. Bokel; M. Botje; N. Brümmer; F. Chlebana; J. Engelen; P. Kooijman; A. Kruse; A. van Sighem; H. Tiecke; W. Verkerke; J. Vossebeld; M. Vreeswijk; L. Wiggers; E. de Wolf; D. Acosta; B. Bylsma; L. S. Durkin; J. Gilmore; C. M. Ginsburg; C. L. Kim; T. Y. Ling; P. Nylander; T. A. Romanowski; H. E. Blaikley; R. J. Cashmore; A. M. Cooper-Sarkar; R. C. E. Devenish; J. K. Edmonds; N. Harnew; M. Lancaster; J. D. McFall; C. Nath; V. A. Noyes; A. Quadt; O. Ruske; J. R. Tickner; H. Uijterwaal; R. Walczak; D. S. Waters; A. Bertolin; R. Brugnera; R. Carlin; F. dal Corso; U. Dosselli; S. Limentani; M. Morandin; M. Posocco; L. Stanco; R. Stroili; C. Voci; J. Bulmahn; R. G. Feild; B. Y. Oh; J. R. Okrasinski; J. J. Whitmore; Y. Iga; G. D'Agostini; G. Marini; A. Nigro; M. Raso; J. C. Hart; N. A. McCubbin; T. P. Shah; E. Barberis; T. Dubbs; C. Heusch; M. van Hook; W. Lockman; J. T. Rahn; H. F.-W. Sadrozinski; A. Seiden; D. C. Williams; O. Schwarzer; A. H. Walenta; H. Abramowicz; G. Briskin; S. Dagan; T. Doeker; S. Kananov; A. Levy; T. Abe; T. Fusayasu; M. Inuzuka; K. Nagano; I. Suzuki; K. Umemori; T. Yamashita; R. Hamatsu; T. Hirose; K. Homma; S. Kitamura; T. Matsushita; K. Yamauchi; R. Cirio; M. Costa; M. I. Ferrero; S. Maselli; V. Monaco; C. Peroni; M. C. Petrucci; R. Sacchi; A. Solano; A. Staiano; M. Dardo; D. C. Bailey; M. Brkic; C.-P. Fagerstroem; G. F. Hartner; K. K. Joo

1997-01-01

35

Temperature-Programmed Scattering (TPS) Study on Reactivity Difference of GaAs and GaAs Oxide Surfaces  

NASA Astrophysics Data System (ADS)

The reactivity of GaAs and GaAs oxide surfaces to trimethylgallium (TMG) was studied by temperature-programmed scattering (TPS) through the energy accommodation coefficient (EAC). The substrate temperature was increased at a constant rate while the scattered TMG was being measured under a constant flux of TMG supplied to the substrate by a cryo-shrouded quadrupole mass spectrometer. Since the detection efficiency of the spectrometer is inversely proportional to the translational velocity of scattered TMG, the observed intensity variation represents the change in translational velocity of reflected TMG during the temperature increase. The variation of the signal intensities was least-squares analyzed to yield the EAC, which is a measure of the surface reactivity. The thus-obtained reactivity of photo-oxidized GaAs to TMG is smaller than that of dark-oxidized GaAs, which is even smaller than that of a bare GaAs surface. This difference in the reactivity is discussed in relation to the mechanism of selective area growth of GaAs using GaAs oxide as a mask.

Sasaki, Masahiro; Yoshida, Seikoh; Yamada, Chikashi

1993-10-01

36

Adiabatic/Nonadiabatic State-to-State Reactive Scattering Dynamics Implemented on Graphics Processing Units.  

PubMed

An efficient graphics processing units (GPUs) version of time-dependent wavepacket code is developed for the atom-diatom state-to-state reactive scattering processes. The propagation of the wavepacket is entirely calculated on GPUs employing the split-operator method after preparation of the initial wavepacket on the central processing unit (CPU). An additional split-operator method is introduced in the rotational part of the Hamiltonian to decrease communication of GPUs without losing accuracy of state-to-state information. The code is tested to calculate the differential cross sections of H + H2 reaction and state-resolved reaction probabilities of nonadiabatic triplet-singlet transitions of O((3)P,(1)D) + H2 for the total angular momentum J = 0. The global speedups of 22.11, 38.80, and 44.80 are found comparing the parallel computation of one GPU, two GPUs by exact rotational operator, and two GPU versions by an approximate rotational operator with serial computation of the CPU, respectively. PMID:23391255

Zhang, Pei-Yu; Han, Ke-Li

2013-02-21

37

Reduced dimensionality quantum reactive scattering: H sub 2 +CN r arrow H+HCN  

SciTech Connect

We apply a recently developed, reduced dimensionality quantum theory of diatom--diatom reactive scattering (Q. Sun and J. M. Bowman, Int. J. Quantum Chem., Symp. {bold 23}, 115 (1989)) to the exoergic H{sub 2}+CN{r arrow}H+HCN reaction, for zero total angular momentum. A new semiempirical, three-dimensional potential surface, which is based in part on {ital ab} {ital initio} calculations of the saddle point properties is also reported. Reaction probabilities for the ground and first excited bending states of HCN are calculated for total energies up to 1.0 and 1.06 eV, respectively. The results show a strong preference for formation of HCN (0{ital v}{sub {ital b}}1) and HCN (0{ital v}{sub {ital b}}2), {ital v}{sub {ital b}}=0 and 1, starting with ground vibrational state reactants. Reaction probabilities for vibrational excitation of H{sub 2} or CN are also reported for both bending states of HCN. Vibrational excitation of H{sub 2} is found to be far more effective in promoting reaction than vibrational excitation of CN.

Sun, Q.; Bowman, J.M. (Department of Chemistry, Emory University, Atlanta, Georgia 30322 (USA))

1990-05-01

38

Diresonance in production and scattering of heavy mesons  

SciTech Connect

We consider the production and scattering amplitudes of heavy mesons in a situation, where there are two closely spaced narrow resonances, whose structure we refer to as a diresonance. Assuming strong overlapping of the resonances coupled to common channels, it is found, using the unitarity and analyticity constraints, that the production amplitudes by a weak source should have similar behavior with energy in different channels. In particular, the ratio of the coefficients for each pole contribution to the production amplitude is fixed at -1.

Dubynskiy, S.; Voloshin, M. B. [School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455 (United States); William I. Fine Theoretical Physics Institute, University of Minnesota, Minneapolis, Minnesota 55455 (United States); and Institute of Theoretical and Experimental Physics, Moscow, 117218 (Russian Federation)

2008-12-01

39

Quantum state resolved inelastic and reactive scattering dynamics in molecular systems via high resolution IR laser spectroscopy  

Microsoft Academic Search

This thesis describes a series of experiments undertaken to investigate inelastic and reactive molecular collision dynamics at the quantum-state resolved level of detail. First, time- and frequency-resolved infrared laser absorption is used to probe state-resolved collisional energy transfer in scattering of fast C1(2P3\\/2) radicals with room temperature HCl molecules. Final state distributions of HCl are monitored via transient infrared laser

William Brewster Chapman

1997-01-01

40

Meson production in high-energy electron-nucleus scattering  

NASA Astrophysics Data System (ADS)

Pseudoscalar mesons can be produced and studied in high-energy electron-nucleus scattering. We review and extend our previous theoretical analysis of meson production in the nuclear Coulomb field. The P??? decay rates are most directly determined for mesons produced in the double-Coulomb region where both photons are nearly real, and provided the hadronic-background contributions remain small. The larger the mass of the meson the higher the electron energy needed to assure such favorable conditions.

Fäldt, Göran

2012-08-01

41

Jet production in deep inelastic scattering at HERA  

SciTech Connect

A number of the most recent results from the wealth of precision HERA data on high transverse energy jet production in deep inelastic scattering are reviewed. These measurements are confronted with predictions from next-to-leading order (NLO) Quantum Chromodynamics and allow the extraction of the strong coupling constant, {alpha}s, and have been used in QCD fits of the parton distribution functions in the proton.

Sutton, M. R. [University College London, Dept of Physics and Astronomy, Gower Street, London WC1E 6BT (United Kingdom)

2006-04-11

42

Reactive Molecular Dynamics Study of TATB Detonation Products  

NASA Astrophysics Data System (ADS)

Under shock conditions 1,3,5-triamino-2,4,6-trinitrobenzene (TATB) reacts to form primarily gaseous N2, H2O, CO2 and CO as well as solid carbon. In a previous study of TATB thermal decomposition based on molecular dynamics (MD) simulations using the ReaxFF reactive force field, we observed a large amount of amorphous (graphite-like) carbon but no diamond structures, even at high pressures. In the current study we focus in greater detail on the reaction products mixture to assess ReaxFF predictions of both the relative stabilities of diamond-rich and graphite-rich product fluids and the equilibrium stoichiometry of CO2, CO and solid carbon at 3250 K and as a function of pressure. In these simulations, we vary systematically the initial phase of solid carbon (pure graphite vs. pure diamond), the initial oxidation state of the remaining gaseous carbon (balanced to either pure CO2 or pure CO), and the material density. In this poster we will summarize the results of these simulations, compare the results with both experimental observations and previous theoretical models, and discuss more generally the extent to which results obtained using short-time MD simulations can influence our understanding of the long-time behavior of real high explosive product mixtures.

Quenneville, Jason; Sewell, Thomas D.; Germann, Timothy C.; Shaw, M. Sam

2009-06-01

43

Dijet production in diffractive deep inelastic scattering at HERA  

NASA Astrophysics Data System (ADS)

The production of dijets in diffractive deep inelastic scattering has been measured with the ZEUS detector at HERA using an integrated luminosity of 61 pb-1. The dijet cross section has been measured for virtualities of the exchanged virtual photon, 5 < Q2 < 100 GeV2, and ?*p centre-of-mass energies, 100 < W < 250 GeV. The jets, identified using the inclusive kT algorithm in the ?*p frame, were required to have a transverse energy E* T,jet > 4 GeV and the jet with the highest transverse energy was required to have E* T,jet > 5 GeV. All jets were required to be in the pseudorapidity range -3.5scattering data.

Chekanov, S.; Derrick, M.; Magill, S.; Musgrave, B.; Nicholass, D.; Repond, J.; Yoshida, R.; Mattingly, M. C. K.; Jechow, M.; Pavel, N.; Yagües Molina, A. G.; Antonelli, S.; Antonioli, P.; Bari, G.; Basile, M.; Bellagamba, L.; Bindi, M.; Boscherini, D.; Bruni, A.; Bruni, G.; Cifarelli, L.; Cindolo, F.; Contin, A.; Corradi, M.; de Pasquale, S.; Iacobucci, G.; Margotti, A.; Nania, R.; Polini, A.; Sartorelli, G.; Zichichi, A.; Bartsch, D.; Brock, I.; Hartmann, H.; Hilger, E.; Jakob, H.-P.; Jüngst, M.; Kind, O. M.; Nuncio-Quiroz, A. E.; Paul, E.; Renner, R.; Samson, U.; Schönberg, V.; Shehzadi, R.; Wlasenko, M.; Brook, N. H.; Heath, G. P.; Morris, J. D.; Capua, M.; Fazio, S.; Mastroberardino, A.; Schioppa, M.; Susinno, G.; Tassi, E.; Kim, J. Y.; Ma, K. J.; Ibrahim, Z. A.; Kamaluddin, B.; Wan Abdullah, W. A. T.; Ning, Y.; Ren, Z.; Sciulli, F.; Chwastowski, J.; Eskreys, A.; Figiel, J.; Galas, A.; Gil, M.; Olkiewicz, K.; Stopa, P.; Zawiejski, L.; Adamczyk, L.; Bo?d, T.; Grabowska-Bo?d, I.; Kisielewska, D.; ?ukasik, J.; Przybycie?, M.; Suszycki, L.; Kota?ski, A.; S?omi?ski, W.; Adler, V.; Behrens, U.; Bloch, I.; Blohm, C.; Bonato, A.; Borras, K.; Ciesielski, R.; Coppola, N.; Dossanov, A.; Drugakov, V.; Fourletova, J.; Geiser, A.; Gladkov, D.; Göttlicher, P.; Grebenyuk, J.; Gregor, I.; Haas, T.; Hain, W.; Horn, C.; Hüttmann, A.; Kahle, B.; Katkov, I. I.; Klein, U.; Kötz, U.; Kowalski, H.; Lobodzinska, E.; Löhr, B.; Mankel, R.; Melzer-Pellmann, I.-A.; Miglioranzi, S.; Montanari, A.; Namsoo, T.; Notz, D.; Rinaldi, L.; Roloff, P.; Rubinsky, I.; Santamarta, R.; Schneekloth, U.; Spiridonov, A.; Stadie, H.; Szuba, D.; Szuba, J.; Theedt, T.; Wolf, G.; Wrona, K.; Youngman, C.; Zeuner, W.; Lohmann, W.; Schlenstedt, S.; Barbagli, G.; Gallo, E.; Pelfer, P. G.; Bamberger, A.; Dobur, D.; Karstens, F.; Vlasov, N. N.; Bussey, P. J.; Doyle, A. T.; Dunne, W.; Forrest, M.; Saxon, D. H.; Skillicorn, I. O.; Gialas, I.; Papageorgiu, K.; Gosau, T.; Holm, U.; Klanner, R.; Lohrmann, E.; Salehi, H.; Schleper, P.; Schörner-Sadenius, T.; Sztuk, J.; Wichmann, K.; Wick, K.; Foudas, C.; Fry, C.; Long, K. R.; Tapper, A. D.; Kataoka, M.; Matsumoto, T.; Nagano, K.; Tokushuku, K.; Yamada, S.; Yamazaki, Y.; Barakbaev, A. N.; Boos, E. G.; Pokrovskiy, N. S.; Zhautykov, B. O.; Aushev, V.; Borodin, M.; Kozulia, A.; Lisovyi, M.; Son, D.; de Favereau, J.; Piotrzkowski, K.; Barreiro, F.; Glasman, C.; Jimenez, M.; Labarga, L.; Del Peso, J.; Ron, E.; Soares, M.; Terrón, J.; Zambrana, M.; Corriveau, F.; Liu, C.; Walsh, R.; Zhou, C.; Tsurugai, T.; Antonov, A.; Dolgoshein, B. A.; Sosnovtsev, V.; Stifutkin, A.; Suchkov, S.; Dementiev, R. K.; Ermolov, P. F.; Gladilin, L. K.; Khein, L. A.; Korzhavina, I. A.; Kuzmin, V. A.; Levchenko, B. B.; Lukina, O. Y.; Proskuryakov, A. S.; Shcheglova, L. M.; Zotkin, D. S.; Zotkin, S. A.; Abt, I.; Büttner, C.; Caldwell, A.; Kollar, D.; Schmidke, W. B.; Sutiak, J.; Grigorescu, G.; Keramidas, A.; Koffeman, E.; Kooijman, P.; Pellegrino, A.; Tiecke, H.; Vázquez, M.; Wiggers, L.; Brümmer, N.; Bylsma, B.; Durkin, L. S.; Lee, A.; Ling, T. Y.; Allfrey, P. D.; Bell, M. A.; Cooper-Sarkar, A. M.; Devenish, R. C. E.; Ferrando, J.; Foster, B.; Korcsak-Gorzo, K.; Oliver, K.; Patel, S.; Roberfroid, V.; Robertson, A.; Straub, P. B.; Uribe-Estrada, C.; Walczak, R.; Bellan, P.; Bertolin, A.; Brugnera, R.; Carlin, R.; Dal Corso, F.; Dusini, S.; Garfagnini, A.; Limentani, S.; Longhin, A.; Stanco, L.; Turcato, M.; Oh, B. Y.; Raval, A.; Ukleja, J.; Whitmore, J. J.; Iga, Y.; D'Agostini, G.; Marini, G.; Nigro, A.; Cole, J. E.; Hart, J. C.; Abramowicz, H.; Gabareen, A.; Ingbir, R.; Kananov, S.; Levy, A.; Smith, O.; Stern, A.; Kuze, M.; Maeda, J.; Hori, R.; Kagawa, S.; Okazaki, N.; Shimizu, S.; Tawara, T.; Hamatsu, R.; Kaji, H.; Kitamura, S.; Ota, O.; Ri, Y. D.; Ferrero, M. I.; Monaco, V.; Sacchi, R.; Solano, A.; Arneodo, M.; Ruspa, M.; Fourletov, S.; Martin, J. F.; Boutle, S. K.; Butterworth, J. M.; Gwenlan, C.; Jones, T. W.; Loizides, J. H.; Sutton, M. R.; Wing, M.; Brzozowska, B.; Ciborowski, J.; Grzelak, G.; Kulinski, P.; ?u?niak, P.; Malka, J.; Nowak, R. J.; Pawlak, J. M.; Tymieniecka, T.; Ukleja, A.; ?arnecki, A. F.; Adamus, M.; Plucinski, P.; Eisenberg, Y.; Giller, I.; Hochman, D.; Karshon, U.; Rosin, M.; Brownson, E.; Danielson, T.; Everett, A.; Kçira, D.; Reeder, D. D.; Ryan, P.; Savin, A. A.; Smith, W. H.; Wolfe, H.; Bhadra, S.; Catterall, C. D.; Cui, Y.; Hartner, G.; Menary, S.; Noor, U.; Standage, J.; Whyte, J.

2007-12-01

44

State-to-state and state-to-all-states reactive scattering angular distributions: F+H /sub 2/. -->. HF+H  

SciTech Connect

How each state-to-state reactive transition determines nonundulatory ''state-to-all-states'' angular distribution has not yet been investigated. Here we present a complete exposure of state-to-state distorted-wave Born-approximation angular distributions in order to examine how the nonoscillatory and backward-peaked state-to-all-states reactive scattering angular distribution occurs.

Emmons, R.W.; Suck, S.H.

1983-04-01

45

The production of positronium and its resonant scattering  

NASA Astrophysics Data System (ADS)

The total cross section of positronium scattering from a variety of atoms and molecules has been found to be unexpectedly close to that of a bare electron moving at the same velocity, despite Ps being neutral and having twice the mass [Science 330, 789 (2010)]. This behaviour appears to extend to velocities where effects such as the Ramsauer-Townsend minima and shape resonances occur for electrons. The latter has now been observed in collisions with CO2. Results are presented along with recent production efficiency measurements of Ps at high energies.

Brawley, S. J.; Williams, A. I.; Shipman, M.; Laricchia, G.

2012-11-01

46

Measurement of D*± production in deep inelastic scattering at HERA  

NASA Astrophysics Data System (ADS)

The production of D *± mesons in deep inelastic ep scattering has been measured for exchanged photon virtualities 5 < Q 2 < 1000 GeV2, using an integrated luminosity of 363 pb-1 with the ZEUS detector at HERA. Differential cross sections have been measured and compared to next-to-leading-order QCD calculations. The cross-sections are used to extract the charm contribution to the proton structure functions, expressed in terms of the reduced charm cross section, ?_{red}^{{coverline{c}}} . Theoretical calculations based on fits to inclusive HERA data are compared to the results.

Abramowicz, H.; Abt, I.; Adamczyk, L.; Adamus, M.; Aggarwal, R.; Antonelli, S.; Antonioli, P.; Antonov, A.; Arneodo, M.; Arslan, O.; Aushev, V.; Aushev, Y.; Bachynska, O.; Bamberger, A.; Barakbaev, A. N.; Barbagli, G.; Bari, G.; Barreiro, F.; Bartosik, N.; Bartsch, D.; Basile, M.; Behnke, O.; Behr, J.; Behrens, U.; Bellagamba, L.; Bertolin, A.; Bhadra, S.; Bindi, M.; Blohm, C.; Bokhonov, V.; Bold, T.; Boos, E. G.; Borras, K.; Boscherini, D.; Bot, D.; Brock, I.; Brownson, E.; Brugnera, R.; Brümmer, N.; Bruni, A.; Bruni, G.; Brzozowska, B.; Bussey, P. J.; Bylsma, B.; Caldwell, A.; Capua, M.; Carlin, R.; Catterall, C. D.; Chekanov, S.; Chwastowski, J.; Ciborowski, J.; Ciesielski, R.; Cifarelli, L.; Cindolo, F.; Contin, A.; Cooper-Sarkar, A. M.; Coppola, N.; Corradi, M.; Corriveau, F.; Costa, M.; D'Agostini, G.; Dal Corso, F.; del Peso, J.; Dementiev, R. K.; De Pasquale, S.; Derrick, M.; Devenish, R. C. E.; Dobur, D.; Dolgoshein, B. A.; Dolinska, G.; Doyle, A. T.; Drugakov, V.; Durkin, L. S.; Dusini, S.; Eisenberg, Y.; Ermolov, P. F.; Eskreys, A.; Fang, S.; Fazio, S.; Ferrando, J.; Ferrero, M. I.; Figiel, J.; Foster, B.; Gach, G.; Galas, A.; Gallo, E.; Garfagnini, A.; Geiser, A.; Gialas, I.; Gizhko, A.; Gladilin, L. K.; Gladkov, D.; Glasman, C.; Gogota, O.; Golubkov, Yu. A.; Göttlicher, P.; Grabowska-Bold, I.; Grebenyuk, J.; Gregor, I.; Grigorescu, G.; Grzelak, G.; Gueta, O.; Guzik, M.; Gwenlan, C.; Haas, T.; Hain, W.; Hamatsu, R.; Hart, J. C.; Hartmann, H.; Hartner, G.; Hilger, E.; Hochman, D.; Hori, R.; Hüttmann, A.; Ibrahim, Z. A.; Iga, Y.; Ingbir, R.; Ishitsuka, M.; Iudin, A.; Jakob, H.-P.; Januschek, F.; Jones, T. W.; Jüngst, M.; Kadenko, I.; Kahle, B.; Kananov, S.; Kanno, T.; Karshon, U.; Karstens, F.; Katkov, I. I.; Kaur, M.; Kaur, P.; Keramidas, A.; Khein, L. A.; Kim, J. Y.; Kisielewska, D.; Kitamura, S.; Klanner, R.; Klein, U.; Koffeman, E.; Kondrashova, N.; Kononenko, O.; Kooijman, P.; Korol, Ie.; Korzhavina, I. A.; Kotanski, A.; Kötz, U.; Kovalchuk, N.; Kowalski, H.; Kuprash, O.; Kuze, M.; Lee, A.; Levchenko, B. B.; Levy, A.; Libov, V.; Limentani, S.; Ling, T. Y.; Lisovyi, M.; Lobodzinska, E.; Lohmann, W.; Löhr, B.; Lohrmann, E.; Long, K. R.; Longhin, A.; Lontkovskyi, D.; Lukina, O. Yu.; Maeda, J.; Magill, S.; Makarenko, I.; Malka, J.; Mankel, R.; Margotti, A.; Marini, G.; Martin, J. F.; Mastroberardino, A.; Mattingly, M. C. K.; Melzer-Pellmann, I.-A.; Mergelmeyer, S.; Miglioranzi, S.; Mohamad Idris, F.; Monaco, V.; Montanari, A.; Morris, J. D.; Mujkic, K.; Musgrave, B.; Nagano, K.; Namsoo, T.; Nania, R.; Nigro, A.; Ning, Y.; Nobe, T.; Notz, D.; Nowak, R. J.; Nuncio-Quiroz, A. E.; Oh, B. Y.; Okazaki, N.; Olkiewicz, K.; Onishchuk, Yu.; Papageorgiu, K.; Parenti, A.; Paul, E.; Pawlak, J. M.; Pawlik, B.; Pelfer, P. G.; Pellegrino, A.; Perlanski, W.; Perrey, H.; Piotrzkowski, K.; Plucinski, P.; Pokrovskiy, N. S.; Polini, A.; Proskuryakov, A. S.; Przybycien, M.; Raval, A.; Reeder, D. D.; Reisert, B.; Ren, Z.; Repond, J.; Ri, Y. D.; Robertson, A.; Roloff, P.; Rubinsky, I.; Ruspa, M.; Sacchi, R.; Samson, U.; Sartorelli, G.; Savin, A. A.; Saxon, D. H.; Schioppa, M.; Schlenstedt, S.; Schleper, P.; Schmidke, W. B.; Schneekloth, U.; Schönberg, V.; Schörner-Sadenius, T.; Schwartz, J.; Sciulli, F.; Shcheglova, L. M.; Shehzadi, R.; Shimizu, S.; Singh, I.; Skillicorn, I. O.; Slominski, W.; Smith, W. H.; Sola, V.; Solano, A.; Son, D.; Sosnovtsev, V.; Spiridonov, A.; Stadie, H.; Stanco, L.; Stefaniuk, N.; Stern, A.; Stewart, T. P.; Stifutkin, A.; Stopa, P.; Suchkov, S.; Susinno, G.; Suszycki, L.; Sztuk-Dambietz, J.; Szuba, D.; Szuba, J.; Tapper, A. D.; Tassi, E.; Terrón, J.; Theedt, T.; Tiecke, H.; Tokushuku, K.; Tomaszewska, J.; Trofymov, A.; Trusov, V.; Tsurugai, T.; Turcato, M.; Turkot, O.; Tymieniecka, T.; Vázquez, M.; Verbytskyi, A.; Viazlo, O.; Vlasov, N. N.; Walczak, R.; Wan Abdullah, W. A. T.; Whitmore, J. J.; Wichmann, K.; Wiggers, L.; Wing, M.; Wlasenko, M.; Wolf, G.; Wolfe, H.; Wrona, K.; Yagües-Molina, A. G.; Yamada, S.; Yamazaki, Y.; Yoshida, R.; Youngman, C.; Zakharchuk, N.; ?arnecki, A. F.; Zawiejski, L.; Zenaiev, O.; Zeuner, W.; Zhautykov, B. O.; Zhmak, N.; Zichichi, A.; Zolkapli, Z.; Zotkin, D. S.

2013-05-01

47

Measurement of beauty production in deep inelastic scattering at HERA  

Microsoft Academic Search

The beauty production cross section for deep inelastic scattering events with at least one hard jet in the Breit frame together with a muon has been measured, for photon virtualities Q2>2?GeV2, with the ZEUS detector at HERA using integrated luminosity of 72 pb?1. The total visible cross section is ?bb¯(ep?e?jet??X)=40.9±5.7(stat.)?4.4+6.0(syst.)?pb. The next-to-leading order QCD prediction lies about 2.5 standard deviations

S. Bhadra; C. D. Catterall; S. Fourletov; G. Hartner; S MIGLIORANZI; M. Soares; J. Standage; J. Repond; R. Yoshida; M. C. K. Mattingly; N. Pavel; P. Antonioli; G. Bari; M. Basile; L. Bellagamba; D. Boscherini; A. Bruni; G. Bruni; G. Cara Romeo; L. Cifarelli; F. Cindolo; A. Contin; M. Corradi; S. de Pasquale; P. Giusti; G. Iacobucci; A. Margotti; A. Montanari; R. Nania; F. Palmonari; A. Pesci; L. Rinaldi; G. Sartorelli; A. Zichichi; G. Aghuzumtsyan; D. Bartsch; I. Brock; S. Goers; H. Hartmann; E. Hilger; P. Irrgang; H.-P. Jakob; O. Kind; U. Meyer; E. Paul; J. Rautenberg; R. Renner; A. Stifutkin; J. Tandler; K. C. Voss; M. Wang; D. S. Bailey; N. H. Brook; J. E. Cole; G. P. Heath; T. Namsoo; S. Robins; M. Wing; M. Capua; A. Mastroberardino; M. Schioppa; G. Susinno; J. Y. Kim; I. T. Lim; K. J. Ma; M. Y. Pac; M. Helbich; Y. Ning; Z. Ren; W. B. Schmidke; F. Sciulli; J. Chwastowski; A. Eskreys; J. Figiel; A. Galas; K. Olkiewicz; P. Stopa; L. Zawiejski; L. Adamczyk; T. Bold; I. Grabowska-Bold; D. Kisielewska; A. M. Kowal; M. Kowal; J. Lukasik; M. Przybycien; L. Suszycki; D. Szuba; J. Szuba; A. Kotanski; W. Slominski; V. Adler; U. Behrens; I. Bloch; K. Borras; V. Chiochia; D. Dannheim; G. Drews; J. Fourletova; U. Fricke; A. Geiser; P. Göttlicher; O. Gutsche; T. Haas; W. Hain; S. Hillert; C. Horn; B. Kahle; U. Kötz; H. Kowalski; G. Kramberger; H. Labes; D. Lelas; H. Lim; B. Löhr; R. Mankel; I.-A. Melzer-Pellmann; C. N. Nguyen; D. Notz; A. E. Nuncio-Quiroz; A. Polini; A. Raval; U. Schneekloth; U. Stösslein; G. Wolf; C. Youngman; W. Zeuner; S. Schlenstedt; G. Barbagli; E. Gallo; C. Genta; P. G. Pelfer; A. Bamberger; A. Benen; F. Karstens; D. Dobur; N. N. Vlasov; P. J. Bussey; A. T. Doyle; J. Ferrando; S. Hanlon; D. H. Saxon; I. O. Skillicorn; I. Gialas; T. Carli; T. Gosau; U. Holm; N. Krumnack; E. Lohrmann; M. Milite; H. Salehi; P. Schleper; T. Schörner-Sadenius; S. Stonjek; K. Wichmann; K. Wick; A. Ziegler; C. Collins-Tooth; C. Foudas; R. Gonçalo; K. R. Long; A. D. Tapper; P. Cloth; D. Filges; M. Kataoka; K. Nagano; K. Tokushuku; S. Yamada; Y. Yamazaki; A. N. Barakbaev; E. G. Boos; N. S. Pokrovskiy; B. O. Zhautykov; D. Son; J. de Favereau; K. Piotrzkowski; F. Barreiro; C. Glasman; O. González; L. Labarga; J. del Peso; E. Tassi; J. Terrón; M. Zambrana; M. Barbi; F. Corriveau; S. Gliga; J. Lainesse; S. Padhi; D. G. Stairs; R. Walsh; T. Tsurugai; A. Antonov; P. Danilov; B. A. Dolgoshein; D. Gladkov; V. Sosnovtsev; S. Suchkov; R. K. Dementiev; P. F. Ermolov; I. I. Katkov; L. A. Khein; I. A. Korzhavina; V. A. Kuzmin; B. B. Levchenko; O. Yu. Lukina; A. S. Proskuryakov; L. M. Shcheglova; S. A. Zotkin; I. Abt; C. Büttner; A. Caldwell; X. Liu; J. Sutiak; N. Coppola; G. Grigorescu; S. Grijpink; A. Keramidas; E. Koffeman; P. Kooijman; E. Maddox; A. Pellegrino; S. Schagen; H. Tiecke; M. Vázquez; L. Wiggers; E. de Wolf; N. Brümmer; B. Bylsma; L. S. Durkin; T. Y. Ling; A. M. Cooper-Sarkar; A. Cottrell; R. C. E. Devenish; B. Foster; G. Grzelak; C. Gwenlan; T. Kohno; S. Patel; P. B. Straub; R. Walczak; P. Bellan; A. Bertolin; R. Brugnera; R. Carlin; F. dal Corso; S. Dusini; A. Garfagnini; S. Limentani; A. Longhin; A. Parenti; M. Posocco; L. Stanco; M. Turcato; E. A. Heaphy; F. Metlica; B. Y. Oh; J. J. Whitmore; Y. Iga; G. D'Agostini; G. Marini; A. Nigro; C. Cormack; J. C. Hart; N. A. McCubbin; C. Heusch; I. H. Park; H. Abramowicz; A. Gabareen; S. Kananov; A. Kreisel; A. Levy; M. Kuze; T. Fusayasu; S. Kagawa; T. Tawara; T. Yamashita; R. Hamatsu; T. Hirose; M. Inuzuka; H. Kaji; S. Kitamura; K. Matsuzawa; M. Costa; M. I. Ferrero; V. Monaco; R. Sacchi; A. Solano; M. Arneodo; M. Ruspa; T. Koop; J. F. Martin; A. Mirea; J. M. Butterworth; R. Hall-Wilton; T. W. Jones; M. S. Lightwood; M. R. Sutton; C. Targett-Adams; J. Ciborowski; R. Ciesielski; P. Luzniak; R. J. Nowak; J. M. Pawlak; J. Sztuk; T. Tymieniecka; A. Ukleja; J. Ukleja; A. F. Zarnecki; M. Adamus; P. Plucinski; Y. Eisenberg; D. Hochman; U. Karshon; M. Riveline; A. Everett; L. K. Gladilin; D. Kçira; S. Lammers; L. Li; D. D. Reeder; M. Rosin; P. Ryan; A. A. Savin; W. H. Smith; S. Dhawan; S. Menary

2004-01-01

48

Mechanically induced generation of highly reactive excited-state oxygen molecules in cluster scattering  

NASA Astrophysics Data System (ADS)

Molecular electronic excitation in (O2)n clusters induced by mechanical collisions via the ``chemistry with a hammer'' is investigated by a combination of molecular dynamics simulations and quantum chemistry calculations. Complete active space self-consistent field augmented with triple-zeta polarizable basis set quantum chemistry calculations of a compressed (O2)2 cluster model in various configurations reveal the emergence of possible pathways for the generation of electronically excited singlet O2 molecules upon cluster compression and vibrational excitation, due to electronic curve-crossing and spin-orbit coupling. Extrapolation of the model (O2)2 results to larger clusters suggests a dramatic increase in the population of electronically excited O2 products, and may account for the recently observed cluster-catalyzed oxidation of silicon surfaces, via singlet oxygen generation induced by cluster impact, followed by surface reaction of highly reactive singlet O2 molecules. Extensive molecular dynamics simulations of (O2)n clusters colliding onto a hot surface indeed reveal that cluster compression is sufficient under typical experimental conditions for nonadiabatic transitions to occur. This work highlights the importance of nonadiabatic effects in the ``chemistry with a hammer.''

Nguyen, Tao-Nhân V.; Timerghazin, Qadir K.; Vach, Holger; Peslherbe, Gilles H.

2011-02-01

49

Argand-diagram representation of transition amplitudes for resonant reactive scattering: e+HCl and e+H/sub 2/  

SciTech Connect

Resonances for rearrangement collisions (reactive scattering) involving the two dissociative attachment processes, e+HCl..-->..H+Cl/sup -/ and e+H/sub 2/..-->..H+H/sup -/, are examined. It is shown from the Argand-diagram representation of transition amplitudes that strong resonance is present in the former but not in the latter. That is, the strong resonance is evidenced by the clear exhibition of a phase change by ..pi.. in a counterclockwise direction in the Argand diagram as the collision energy increases. Such a manifest phase change is absent in the dissociative attachment process of e+H/sub 2/..-->..H+H/sup -/. This is attributed to the presence of equally strong, direct, and resonant scattering processes, and to the strong influence of mutually destructive interference.

Lutrus, C.K.; Suck Salk, S.H.

1989-01-01

50

Oxidation of Reactive Nitrogen and Ozone Production in Tokyo  

NASA Astrophysics Data System (ADS)

Ground based measurements of NOx (NO + NO2), nitric acid (HNO3), particulate nitrate (NO3-), peroxyacyl nitrates (PANs), and total reactive nitrogen (NOy) were conducted in Tokyo in winter (January-February 2004), summer (July-August 2003 and 2004), and fall (October 2003). Carbon monoxide (CO), ozone (O3), non-methane hydrocarbons (NMHCs) and actinic flux were also measured during these periods. Average mixing ratios of these species and the NOx/NOy, HNO3/NOy, NO3-/NOy, and PANs/NOy ratios showed distinct diurnal-seasonal variations. The NOx/NOy ratios were 0.63-0.95 on high J(O1D) days, and 0.77-0.94 on low J(O1D) days. In summer and winter, total nitrate (TN = HNO3 + NO3-) was the dominant form of the NOx oxidation products (NOz = NOy - NOx) during the daytime on high J(O1D) days, and PANs were minor component species. The partitioning of TN was controlled mainly by temperature and the shit of the partitioning to NO3- at low temperature suppressed removal of NOy by dry deposition of HNO3. Removal rate of NOy is estimated using CO as a tracer. The estimated loss of NOy (LNOy) was largest during the daytime in summer (35%), while smallest (0%) in winter. The corrected ozone production efficiency (OPEx), which is defined as the linear regression slope of the observed Ox (= O3 + NO2) versus NOz* (= NOz + LNOy), is estimated to be 2.5. The estimated OPEx is slightly lower than those obtained in the U.S. urban air, which is probably due to lower ratios of NMHCs to NOx in this study. Possible factors controlling the OPEx will be discussed in detail.

Fukuda, M.; Kondo, Y.; Miyazaki, Y.; Morino, Y.; Takegawa, N.; Miyakawa, T.; Komazaki, Y.; Tanimoto, H.; Yokouchi, Y.; Kanaya, Y.; McKenzie, R.; Johnston, P.

2005-12-01

51

Flow cytometric evaluation of nanoparticles using side-scattered light and reactive oxygen species-mediated fluorescence-correlation with genotoxicity.  

PubMed

We recently clarified that the side-scatter(ed) light (SSC) of flow cytometry (FCM) could be used as a guide to measure the uptake potential of nanoparticles [ Suzuki et al. Environ. Sci. Technol. 2007 , 41 , 3018 - 3024 ]. In this paper, the method was improved so as to be able to determine simultaneously the uptake potential of nanoparticles and the production of reactive oxygen species (ROS), and correlations with genotoxicity were evaluated. In the FCM analysis, SSC and fluorescence of 6-carboxy-2,7'-diclorodihydrofluorescein diacetate, di(acetoxy ester) based on ROS production were concurrently detected after treatments with ZnO, CuO, Fe(3)O(4), TiO(2), and Ag nanoparticles. The ZnO and CuO nanoparticles caused high ROS production, which was more significant in the cells with higher SSC intensity. The increase of SSC intensity was more significant for TiO(2) than ZnO and CuO, whereas ROS production was higher for ZnO and CuO than TiO(2), suggesting that the extent of ROS production based on the uptake of nanoparticles differed with each kind of nanoparticle. ROS production was correlated with generation of the phosphorylated histone H2AX (?-H2AX), a marker of DNA damage, and an antioxidant, n-acetylcysteine, could partially suppress the ?-H2AX. This method makes it possible to predict not only uptake potential but also genotoxicity. PMID:22703531

Toduka, Yousuke; Toyooka, Tatsushi; Ibuki, Yuko

2012-07-06

52

Reactive and anisotropic elastic scattering of highly laser-vibration-excited diatomic molecules  

Microsoft Academic Search

The effect of vibration excitation on the simple (reactive) anisotropic atom-molecule interaction systems under single collision conditions was investigated. The laser molecular beam apparatus allows a particle detection which is rotation and vibration selective and orientation dependent. The anisotropic, vibration dependent total integral cross sections of the systems Li2-He and Li2-Kr were determined. The measurements on the reactive system Li2-Na

H.-G. Rubahn

1988-01-01

53

Reactivity impact of {sup 16}O thermal elastic-scattering nuclear data for some numerical and critical benchmark systems  

SciTech Connect

The thermal neutron-elastic-scattering cross-section data for {sup 16}O used in various modern evaluated-nuclear-data libraries were reviewed and found to be generally too high compared with the best available experimental measurements. Some of the proposed revisions to the ENDF/B-VII.0 {sup 16}O data library and recent results from the TENDL system increase this discrepancy further. The reactivity impact of revising the {sup 16}O data downward to be consistent with the best measurements was tested using the JENDL-3.3 {sup 16}O cross-section values and was found to be very small in MCNP5 simulations of the UO{sub 2} and reactor-recycle MOX-fuel cases of the ANS Doppler-defect numerical benchmark. However, large reactivity differences of up to about 14 mk (1400 pcm) were observed using {sup 16}O data files from several evaluated-nuclear-data libraries in MCNP5 simulations of the Los Alamos National Laboratory HEU heavy-water solution thermal critical experiments, which were performed in the 1950's. The latter result suggests that new measurements using HEU in a heavy-water-moderated critical facility, such as the ZED-2 zero-power reactor at the Chalk River Laboratories, might help to resolve the discrepancy between the {sup 16}O thermal elastic-scattering cross-section values and thereby reduce or better define its uncertainty, although additional assessment work would be needed to confirm this. (authors)

Kozier, K. S.; Roubtsov, D. [AECL, Chalk River Laboratories, Chalk River, ON (Canada); Plompen, A. J. M.; Kopecky, S. [EC-JRC, Inst. for Reference Materials and Measurements, Retieseweg 111, 2440 Geel (Belgium)

2012-07-01

54

Measurement of beauty production in deep inelastic scattering at HERA  

NASA Astrophysics Data System (ADS)

The beauty production cross section for deep inelastic scattering events with at least one hard jet in the Breit frame together with a muon has been measured, for photon virtualities Q2>2 GeV2, with the ZEUS detector at HERA using integrated luminosity of 72 pb-1. The total visible cross section is ?bb¯(ep?e jet ?X)=40.9±5.7(stat.)-4.4+6.0(syst.) pb. The next-to-leading order QCD prediction lies about 2.5 standard deviations below the data. The differential cross sections are in general consistent with the NLO QCD predictions; however at low values of Q2, Bjorken x, and muon transverse momentum, and high values of jet transverse energy and muon pseudorapidity, the prediction is about two standard deviations below the data.

ZEUS Collaboration; Chekanov, S.; Derrick, M.; Loizides, J. H.; Magill, S.; Miglioranzi, S.; Musgrave, B.; Repond, J.; Yoshida, R.; Mattingly, M. C. K.; Pavel, N.; Antonioli, P.; Bari, G.; Basile, M.; Bellagamba, L.; Boscherini, D.; Bruni, A.; Bruni, G.; Cara Romeo, G.; Cifarelli, L.; Cindolo, F.; Contin, A.; Corradi, M.; de Pasquale, S.; Giusti, P.; Iacobucci, G.; Margotti, A.; Montanari, A.; Nania, R.; Palmonari, F.; Pesci, A.; Rinaldi, L.; Sartorelli, G.; Zichichi, A.; Aghuzumtsyan, G.; Bartsch, D.; Brock, I.; Goers, S.; Hartmann, H.; Hilger, E.; Irrgang, P.; Jakob, H.-P.; Kind, O.; Meyer, U.; Paul, E.; Rautenberg, J.; Renner, R.; Stifutkin, A.; Tandler, J.; Voss, K. C.; Wang, M.; Bailey, D. S.; Brook, N. H.; Cole, J. E.; Heath, G. P.; Namsoo, T.; Robins, S.; Wing, M.; Capua, M.; Mastroberardino, A.; Schioppa, M.; Susinno, G.; Kim, J. Y.; Lim, I. T.; Ma, K. J.; Pac, M. Y.; Helbich, M.; Ning, Y.; Ren, Z.; Schmidke, W. B.; Sciulli, F.; Chwastowski, J.; Eskreys, A.; Figiel, J.; Galas, A.; Olkiewicz, K.; Stopa, P.; Zawiejski, L.; Adamczyk, L.; Bo?d, T.; Grabowska-Bo?d, I.; Kisielewska, D.; Kowal, A. M.; Kowal, M.; ?ukasik, J.; Przybycie?, M.; Suszycki, L.; Szuba, D.; Szuba, J.; Kota?ski, A.; S?omi?ski, W.; Adler, V.; Behrens, U.; Bloch, I.; Borras, K.; Chiochia, V.; Dannheim, D.; Drews, G.; Fourletova, J.; Fricke, U.; Geiser, A.; Göttlicher, P.; Gutsche, O.; Haas, T.; Hain, W.; Hillert, S.; Horn, C.; Kahle, B.; Kötz, U.; Kowalski, H.; Kramberger, G.; Labes, H.; Lelas, D.; Lim, H.; Löhr, B.; Mankel, R.; Melzer-Pellmann, I.-A.; Nguyen, C. N.; Notz, D.; Nuncio-Quiroz, A. E.; Polini, A.; Raval, A.; Schneekloth, U.; Stösslein, U.; Wolf, G.; Youngman, C.; Zeuner, W.; Schlenstedt, S.; Barbagli, G.; Gallo, E.; Genta, C.; Pelfer, P. G.; Bamberger, A.; Benen, A.; Karstens, F.; Dobur, D.; Vlasov, N. N.; Bussey, P. J.; Doyle, A. T.; Ferrando, J.; Hamilton, J.; Hanlon, S.; Saxon, D. H.; Skillicorn, I. O.; Gialas, I.; Carli, T.; Gosau, T.; Holm, U.; Krumnack, N.; Lohrmann, E.; Milite, M.; Salehi, H.; Schleper, P.; Schörner-Sadenius, T.; Stonjek, S.; Wichmann, K.; Wick, K.; Ziegler, A.; Ziegler, Ar.; Collins-Tooth, C.; Foudas, C.; Gonçalo, R.; Long, K. R.; Tapper, A. D.; Cloth, P.; Filges, D.; Kataoka, M.; Nagano, K.; Tokushuku, K.; Yamada, S.; Yamazaki, Y.; Barakbaev, A. N.; Boos, E. G.; Pokrovskiy, N. S.; Zhautykov, B. O.; Son, D.; de Favereau, J.; Piotrzkowski, K.; Barreiro, F.; Glasman, C.; González, O.; Labarga, L.; del Peso, J.; Tassi, E.; Terrón, J.; Zambrana, M.; Barbi, M.; Corriveau, F.; Gliga, S.; Lainesse, J.; Padhi, S.; Stairs, D. G.; Walsh, R.; Tsurugai, T.; Antonov, A.; Danilov, P.; Dolgoshein, B. A.; Gladkov, D.; Sosnovtsev, V.; Suchkov, S.; Dementiev, R. K.; Ermolov, P. F.; Katkov, I. I.; Khein, L. A.; Korzhavina, I. A.; Kuzmin, V. A.; Levchenko, B. B.; Lukina, O. Yu.; Proskuryakov, A. S.; Shcheglova, L. M.; Zotkin, S. A.; Abt, I.; Büttner, C.; Caldwell, A.; Liu, X.; Sutiak, J.; Coppola, N.; Grigorescu, G.; Grijpink, S.; Keramidas, A.; Koffeman, E.; Kooijman, P.; Maddox, E.; Pellegrino, A.; Schagen, S.; Tiecke, H.; Vázquez, M.; Wiggers, L.; de Wolf, E.; Brümmer, N.; Bylsma, B.; Durkin, L. S.; Ling, T. Y.; Cooper-Sarkar, A. M.; Cottrell, A.; Devenish, R. C. E.; Foster, B.; Grzelak, G.; Gwenlan, C.; Kohno, T.; Patel, S.; Straub, P. B.; Walczak, R.; Bellan, P.; Bertolin, A.; Brugnera, R.; Carlin, R.; dal Corso, F.; Dusini, S.; Garfagnini, A.; Limentani, S.; Longhin, A.; Parenti, A.; Posocco, M.; Stanco, L.; Turcato, M.; Heaphy, E. A.; Metlica, F.; Oh, B. Y.; Whitmore, J. J.; Iga, Y.; D'Agostini, G.; Marini, G.; Nigro, A.; Cormack, C.; Hart, J. C.; McCubbin, N. A.; Heusch, C.; Park, I. H.; Abramowicz, H.; Gabareen, A.; Kananov, S.; Kreisel, A.; Levy, A.; Kuze, M.; Fusayasu, T.; Kagawa, S.; Tawara, T.; Yamashita, T.; Hamatsu, R.; Hirose, T.; Inuzuka, M.; Kaji, H.; Kitamura, S.; Matsuzawa, K.; Costa, M.; Ferrero, M. I.; Monaco, V.; Sacchi, R.; Solano, A.; Arneodo, M.; Ruspa, M.; Koop, T.; Martin, J. F.; Mirea, A.; Butterworth, J. M.; Hall-Wilton, R.; Jones, T. W.; Lightwood, M. S.; Sutton, M. R.; Targett-Adams, C.; Ciborowski, J.; Ciesielski, R.; ?u?niak, P.; Nowak, R. J.; Pawlak, J. M.; Sztuk, J.; Tymieniecka, T.; Ukleja, A.; Ukleja, J.; ?arnecki, A. F.; Adamus, M.; Plucinski, P.; Eisenberg, Y.; Hochman, D.; Karshon, U.; Riveline, M.; Everett, A.; Gladilin, L. K.; Kçira, D.; Lammers, S.; Li, L.; Reeder, D. D.; Rosin, M.; Ryan, P.; Savin, A. A.; Smith, W. H.; Dhawan, S.; Bhadra, S.; Catterall, C. D.; Fourletov, S.; Hartner, G.; Menary, S.; Soares, M.; Standage, J.

2004-10-01

55

Increased hydrogen peroxide and thiobarbituric acid-reactive products in expired breath condensate of asthmatic patients  

Microsoft Academic Search

Increased hydrogen peroxide and thiobarbituric acid-reactive products in expired breath condensate of asthmatic patients. A. Antczak, D. Nowak, B. Shariati, M. Król, G. Piasecka, Z. Kurmanowska. ©ERS Journals Ltd 1997. ABSTRACT: Symptoms of bronchial asthma are a manifestation of airway in- flammation. Circulatory leucocytes (predominantly eosinophils, mast cells and neu- trophils), release inflammatory mediators, including reactive oxygen species, i.e. superoxide

A. Antczak; D. Nowak; B. Shariati; M. Król; G. Piasecka; Z. Kurmanowska

1997-01-01

56

Reactive and nonreactive scattering of N2 from Ru(0001): A six-dimensional adiabatic study  

NASA Astrophysics Data System (ADS)

We have studied the dissociative chemisorption and scattering of N2 on and from Ru(0001), using a six-dimensional quasiclassical trajectory method. The potential energy surface, which depends on all the molecular degrees of freedom, has been built applying a modified Shepard interpolation method to a data set of results from density functional theory, employing the RPBE generalized gradient approximation. The frozen surface and Born-Oppenheimer [Ann. Phys. (Leipzig) 84, 457 (1927)] approximations were used, neglecting phonons and electron-hole pair excitations. Dissociative chemisorption probabilities are found to be very small even for translational energies much higher than the minimum reaction barrier, in good agreement with experiment. A comparison to previous low dimensional calculations shows the importance of taking into account the multidimensional effects of N2 rotation and translation parallel to the surface. The new calculations strongly suggest a much smaller role of nonadiabatic effects than previously assumed on the basis of a comparison between low dimensional results and experiments [J. Chem. Phys. 115, 9028 (2001)]. Also in agreement with experiment, our theoretical results show a strong dependence of reaction on the initial vibrational state. Computed angular scattering distributions and parallel translation energy distributions are in good agreement with experiments on scattering, but the theory overestimates vibrational and rotational excitations in scattering.

Díaz, C.; Vincent, J. K.; Krishnamohan, G. P.; Olsen, R. A.; Kroes, G. J.; Honkala, K.; Nørskov, J. K.

2006-09-01

57

Production of Ozone and Reactive Oxygen Species After Welding  

Microsoft Academic Search

Many toxic substances including heavy metals, ozone, carbon monoxide, carbon dioxide, and nitrogen oxides are generated during\\u000a welding. Ozone (O3) is a strong oxidant that generates reactive oxygen species (ROS) in tissue, and ambient ROS exposure associated with particles\\u000a has been determined to cause DNA damage. Ozone is produced within 30 seconds during welding. However, the length of time that

H. H. Liu; Y. C. Wu; H. L. Chen

2007-01-01

58

Reactive Molecular Dynamics Study of TATB Detonation Products  

Microsoft Academic Search

Under shock conditions 1,3,5-triamino-2,4,6-trinitrobenzene (TATB) reacts to form primarily gaseous N2, H2O, CO2 and CO as well as solid carbon. In a previous study of TATB thermal decomposition based on molecular dynamics (MD) simulations using the ReaxFF reactive force field, we observed a large amount of amorphous (graphite-like) carbon but no diamond structures, even at high pressures. In the current

Jason Quenneville; Thomas D. Sewell; Timothy C. Germann; M. Sam Shaw

2009-01-01

59

Reactivity and stability of various metal-silicon interfaces studied by high energy ion scattering  

NASA Astrophysics Data System (ADS)

Measurements on the reactivity and stability of interfaces have been performed for various metal-Si (100) junctions using the displacement-sensitive high-energy-ion-channeling technique. The intensity variations of the Si substrate interface peak (IP) were evaluated as functions of beam dose and energy of ions irradiated in the substrate channeling direction. For Cu- and Al-Si systems, the IP variations with beam dose are rapid and large at the onset of beam irradiation, and tend to be saturated as in the case of Au-Si system previously reported, while they are relatively small and proportional to dosage for Ta-, Ti-, and W-Si systems. The IP variations with incident beam energy are compared with those calculated by a Monte Carlo simulation for ideal Si [100] strings, giving information on the magnitude of the atomic displacements. All data obtained can be explained in terms of the reactivity difference of the deposited metals and the stability of the interfacial layers formed. The mechanism of the ion-beam-induced interfacial reaction is discussed.

Moon, Jong; Ito, Toshimichi; Hiraki, Akio

1992-12-01

60

X-ray scattering for the determination of fat content in dairy products  

NASA Astrophysics Data System (ADS)

The scattering of X-rays from biological samples has been shown to produce characteristic profiles, which depend on their molecular structure. The highly ordered fat molecules in an adipose tissue result in a relatively sharp scattering peak at 1.1 nm-1 with a scattering profile, which is considerably different from the scattering profile of a water-rich tissue. The latter is characterized by a broad scattering peak at about 1.6 nm-1. A biological sample consisting of a mixture of both adipose and a water-rich tissue is expected to show a scattering profile, which is directly linked to the relative contribution of each component and would reflect the percentage by volume of each component in the mixture. In this work, X-ray scattering profiles of a number of dairy products and water are measured. The values of two selected X-ray scattering characterization parameters (I1/I2% and areas A1/A2% of the scattering peaks at 1.1 and 1.6 nm-1, respectively) are plotted against the fat content of each of the measured dairy samples. Results show a strong linear dependence of each of the X-ray scattering parameters and the fat content of the investigated dairy products. These results suggest a possible use of such technique as a new, simple and straight forward method for determination of fat content of dairy products that would join and support the currently available techniques.

Elshemey, Wael M.

2011-07-01

61

Higher-order split operator schemes for solving the Schrödinger equation in the time-dependent wave packet method: applications to triatomic reactive scattering calculations.  

PubMed

The efficiency of the numerical propagators for solving the time-dependent Schrödinger equation in the wave packet approach to reactive scattering is of vital importance. In this Perspective, we first briefly review the propagators used in quantum reactive scattering calculations and their applications to triatomic reactions. Then we present a detailed comparison of about thirty higher-order split operator propagators for solving the Schrödinger equation with their applications to the wave packet evolution within a one-dimensional Morse potential, and the total reaction probability calculations for the H + HD, H + NH, H + O(2), and F + HD reactions. These four triatomic reactions have quite different dynamic characteristics and thus provide a comprehensive picture of the relative advantages of these higher-order propagation methods for describing reactive scattering dynamics. Our calculations reveal that the most often used second-order split operator method is typically more efficient for a direct reaction, particularly for those involving flat potential energy surfaces. However, the optimal higher-order split operator methods are more suitable for a reaction with resonances and intermediate complexes or a reaction experiencing potential energy surface with fluctuations of considerable amplitude. Three 4th-order and one 6th-order split operator methods, which are most efficient for solving reactive scattering in various conditions among the tested ones, are recommended for general applications. In addition, a brief discussion on the relative performance between the Chebyshev real wave packet method and the split operator method is given. The results in this Perspective are expected to stimulate more applications of (high-order) split operators to the quantum reactive scattering calculation and other related problems. PMID:22234283

Sun, Zhigang; Yang, Weitao; Zhang, Dong H

2012-01-10

62

Detection of mitochondria-derived reactive oxygen species production by the chemilumigenic probes lucigenin and luminol  

Microsoft Academic Search

Both lucigenin and luminol have widely been used as chemilumigenic probes for detecting reactive oxygen species (ROS) production by various cellular systems. Our laboratory has previously demonstrated that lucigenin localizes to the mitochondria of rat alveolar macrophages and that lucigenin-derived chemiluminescence (CL) appears to reflects superoxide (O??2) production by mitochondria in the unstimulated macrophages. In this study, we further examined

Yunbo Li; Hong Zhu; Michael A. Trush

1999-01-01

63

A comparison of Monte Carlo simulations of electron scattering and X-ray production in solids  

Microsoft Academic Search

Monte Carlo simulations of electron scattering in silver have been performed at 6 and 20 keV to investigate the relation between electron transport, backscattering and depth distribution of characteristic X-ray production of tracer elements. The simulation models used combine the use of elastic cross sections, either of Rutherford or of Mott type, with approaches to inelastic scattering given by either

Ding Ze-Jun; Wu Ziqin

1993-01-01

64

Exclusive Vector Meson Production and Deep Virtual Compton Scattering in Electron-Ion Collisions  

SciTech Connect

We calculate the nuclear cross section for coherent and incoherent deep virtual Compton scattering as well as for coherent and incoherent vector meson production for the mesons J/{Psi}, {phi} and {rho} within the QCD color dipole picture, including saturation effects. Theoretical estimates for scattering on both light and heavy nuclei are given over a wide range of energy.

Cazaroto, E. R.; Navarra, F. S. [Instituto de Fisica, Universidade de Sao Paulo, C.P 66318, 05389-970 Sao Paulo, SP (Brazil); Carvalho, F. [Depto de ciencias exatas e da terra, Universidade Federal de Sao Paulo, Sao Paulo, SP (Brazil); Kugeratski, M. S. [Universidade Federal de Santa Catarina, Curitibanos, SC (Brazil); Goncalves, V. P. [Instituto de Fisica e Matematica, Universidade Federal de Pelotas, Pelotas, RS (Brazil)

2010-11-12

65

Production of Reactive Oxygen Species by Polyhalogenated Cyclic Hydrocarbons (PCH).  

National Technical Information Service (NTIS)

We have developed a HPLC method for the simultaneous determination of four lipid peroxidation products, namely, formaldehyde, malondialdehyde, acetaldehyde and acetone. This procedure has wide-spread applicability to exposure to environmental pollutants a...

S. J. Stohs

1991-01-01

66

Stress Granules Inhibit Apoptosis by Reducing Reactive Oxygen Species Production  

PubMed Central

Cells can undergo two alternative fates following exposure to environmental stress: they either induce apoptosis or inhibit apoptosis and then repair the stress-induced alterations. These processes minimize cell loss and prevent the survival of cells with aberrant DNA and protein alterations. These two alternative fates are partly controlled by stress granules (SGs). While arsenite, hypoxia, and heat shock induce the formation of SGs that inhibit apoptosis, X-ray irradiation and genotoxic drugs do not induce SGs, and they are more prone to trigger apoptosis. However, it is unclear precisely how SGs control apoptosis. This study found that SGs suppress the elevation of reactive oxygen species (ROS), and this suppression is essential for inhibiting ROS-dependent apoptosis. This antioxidant activity of SGs is controlled by two SG components, GTPase-activating protein SH3 domain binding protein 1 (G3BP1) and ubiquitin-specific protease 10 (USP10). G3BP1 elevates the steady-state ROS level by inhibiting the antioxidant activity of USP10. However, following exposure to arsenite, G3BP1 and USP10 induce the formation of SGs, which uncovers the antioxidant activity of USP10. We also found that the antioxidant activity of USP10 requires the protein kinase activity of ataxia telangiectasia mutated (ATM). This work reveals that SGs are critical redox regulators that control cell fate under stress conditions.

Takahashi, Masahiko; Higuchi, Masaya; Matsuki, Hideaki; Yoshita, Manami; Ohsawa, Toshiaki; Oie, Masayasu

2013-01-01

67

Reactant-product decoupling approach to half-scattering problems: Photodissociation of H{sub 2}O in three dimensions  

SciTech Connect

In this paper, we present the RPD (reactant-product decoupling) approach to the calculation of final-state distribution in photodissociation of H{sub 2}O in three-dimensional space. Although the RPD approach was recently developed for bimolecular state-to-state reactive scattering calculations, its application to photodissociation dynamics is very attractive. Specifically in photodissociation, the interaction (reactant) component wavefunction {psi}{sub r} (which in the present case of photodissociation is replaced by the interaction component {psi}{sub int}) is nonzero only in the strong interaction region, which greatly simplifies the numerical calculation for {psi}{sub int} in comparison to that for {psi}{sub r} in a full bimolecular reactive scattering calculation. In the following report, the time-dependent implementation of the RPD approach to the photodissociation of H{sub 2}O in three dimensions is given and the calculated rovibrational state distributions of the OH fragment are presented. {copyright} {ital 1997 American Institute of Physics.}

Wang, D.; Zhu, W.; Zhang, J.Z. [Department of Chemistry, New York University, New York, New York 10003 (United States); Kouri, D.J. [Departments of Chemistry and Physics, University of Houston, Houston, Texas 77004 (United States)

1997-07-01

68

Reactivation of Kaposi's sarcoma-associated herpesvirus by natural products from Kaposi's sarcoma endemic regions  

PubMed Central

Kaposi’s sarcoma (KS) and its causative agent, Kaposi’s sarcoma associated herpesvirus (KSHV/HHV-8), a gamma2 herpesvirus, have distinctive geographical distributions that are largely unexplained. We propose the “oncoweed” hypothesis to explain these differences, namely that environmental cofactors present in KS endemic regions cause frequent reactivation of KSHV in infected subjects, leading to increased viral shedding and transmission leading to increased prevalence of KSHV infection as well as high viral load levels and antibody titers. Reactivation also plays a role in the pathogenesis of KSHV-associated malignancies. To test this hypothesis, we employed an in vitro KSHV reactivation assay that measured increases in KSHV viral load in KSHV infected primary effusion lymphoma (PEL) cells and screened aqueous natural product extracts from KS endemic regions. Of 4,842 extracts from 38 countries, 184 (5%) caused KSHV reactivation. Extracts that caused reactivation came from a wide variety of plant families, and extracts from Africa, where KSHV is highly prevalent, caused the greatest level of reactivation. Time course experiments were performed using 28 extracts that caused the highest levels of reactivation. The specificity of the effects on viral replication was examined using transcriptional profiling of all viral mRNAs. The array data indicated that the natural extracts caused an ordered cascade of lytic replication similar to that seen after induction with synthetic activators. These in vitro data provide support for the “oncoweed” hypothesis by demonstrating basic biological plausibility.

Whitby, Denise; Marshall, Vickie A.; Bagni, Rachel K.; Miley, Wendell J.; McCloud, Thomas G.; Hines-Boykin, Rebecca; Goedert, James J.; Conde, Betty A.; Nagashima, Kunio; Mikovits, Judy; Dittmer, Dirk P.; Newman, David J.

2010-01-01

69

Differential production of reactive oxygen species by subsets of human spermatozoa at different stages of maturation  

Microsoft Academic Search

BACKGROUND: Reactive oxygen species (ROS)-mediated damage to human spermatozoa has been implicated in the pathogenesis of male infertility. Although ROS production by human spermatozoa has been extensively studied, the cell-to-cell variation in ROS production by spermatozoa at different stages of maturation has never been investigated. METHODS: In this study, we determined ROS production by subsets of human spermatozoa at different

E. Gil-Guzman; M. Ollero; M. C. Lopez; R. K. Sharma; J. G. Alvarez; A. J. Thomas; A. Agarwal

2001-01-01

70

Effects of reactive oxygen species on ?-tocopherol production in mitochondria and chloroplasts of Euglena gracilis  

Microsoft Academic Search

The effects of reactive oxygen species (ROS) on ?-tocopherol production in mitochondria and chloroplasts of Euglena gracilis were investigated. Addition of an organic carbon source to the medium resulted in increased mitochondrial activity, intracellular\\u000a O2\\u000a - concentration and ?-tocopherol productivity in E. gracilis W14ZUL (a chloroplast deficient mutant). ?-Tocopherol productivity of the wild-type strain (with both mitochondria and chloroplast)\\u000a was

Tomoya Fujita; James C. Ogbonna; Hideo Tanaka; Hideki Aoyagi

2009-01-01

71

Production of reactive oxygen metabolites induced by asbestos fibres in human polymorphonuclear leucocytes.  

PubMed Central

The ability of quartz and various asbestos fibres to induce the production of reactive oxygen metabolites in human polymorphonuclear leucocytes was assessed. A chemiluminescence assay showed that the activation of polymorphonuclear leucocytes was induced in the following order of effect: quartz; chrysotile A; crocidolite; chrysotile B; amosite; and anthophyllite. Only slight chemiluminescence was produced by cells exposed to wollastonites and titanium dioxide. A positive correlation was seen between production of chemiluminescence and red cell haemolysis. Our results suggest that the potential of various environmental particles and mineral fibres to induce inflammation, fibrosis, and cancer of the lung could be related to their ability to induce inflammatory cells to produce reactive oxygen metabolites.

Hedenborg, M; Klockars, M

1987-01-01

72

Catalytic reactive distillation process development for 1,1 diethoxy butane production from renewable sources.  

PubMed

Some acetals can be produced from renewable resources (bioalcohols) and seem to be good candidates for different applications such as oxygenated diesel additives. In the present case the production of 1,1 diethoxy butane from bioethanol and butanal is presented. Butanal can be obtained from biobutanol following a partial oxidation or a dehydrogenation process. In this paper innovative process development about the synthesis of the mentioned acetal including catalytic reactive distillation experimental and simulation results will be presented and discussed. Katapak SP modules containing Amberlyst 47 resin were used as structured catalytic packings. This reactive system allowed reaching higher conversions than the equilibrium ones at the same temperatures. All the experimental data gathered allowed to tune a simulation model for the reactive distillation operation which showed a fairly good behavior in order to perform initial 1,1 diethoxy butane production process design studies. PMID:20833537

Agirre, I; Barrio, V L; Güemez, B; Cambra, J F; Arias, P L

2010-08-26

73

Helicobacter pylori stimulates antral mucosal reactive oxygen metabolite production in vivo  

Microsoft Academic Search

To determine if reactive oxygen metabolites have a pathogenic role in Helicobacter pylori (H pylori) related gastroduodenal disease, this study measured their production in antral mucosal biopsy specimens. Two related chemiluminescence techniques were used comparing H pylori positive (n = 105) and negative patients (n = 64) with a similar spectrum of macroscopic disease. After chemiluminescence assays, biopsy specimens were

G. R. Davies; N. J. Simmonds; T. R. J. Stevens; M. T. Sheaff; N. Banatvala; I. F. Laurenson; D. R. Blake; D. S. Rampton

1994-01-01

74

Nucleation of product phase in reactive diffusion of Al\\/Co  

Microsoft Academic Search

The reactive interdiffusion of Co\\/Al bilayers is studied by atom probe tomography. For that, metallic thin films were deposited on tungsten substrates preshaped by field evaporation. Owing to the outstanding resolution of the method and its real three-dimensional analysis, the nucleation of the first product could be characterized in detail. It is clearly seen that interdiffusion of the initial Al

V. Vovk; G. Schmitz; R. Kirchheim

2004-01-01

75

A CLEANER PRODUCTION APPROACH FOR MINIMISATION OF TOTAL DISSOLVED SOLIDS IN REACTIVE DYEING EFFLUENTS  

Microsoft Academic Search

This paper discusses a Cleaner Production (CP) approach for minimisation of Total Dissolved Solids (TDS) in reactive dyeing effluents. About 900 small and medium scale units carry out such operations in Tirupur, a small city in South India. Two principal issues of concern are the TDS and Colour of the effluents. The studies showed that a combination of low material

Kurian Joseph

76

The catalytically active copper-amyloid-Beta state: coordination site responsible for reactive oxygen species production.  

PubMed

Copper-amyloid-? ROS production: Copper ions (red sphere, see picture) have been found to accumulate in amyloid-? plaques and play a role in the generation of reactive oxygen species (ROS) within this context. Mass spectrometry studies were able to detail the sites of oxidation damage and shed new light on the mechanism of ROS production, important for the understanding of the pathogenicity of amyloid-? peptides. PMID:24038998

Cassagnes, Laure-Estelle; Hervé, Vincent; Nepveu, Françoise; Hureau, Christelle; Faller, Peter; Collin, Fabrice

2013-09-03

77

Generation of reactive oxygen species and photon emission from a browned product.  

PubMed

The properties of photon emission arising from a browned product were investigated. The photon intensity of the browned product was proportional to the absorbancy at 420 nm, and was influenced by the amino acid structure. The fluorescence spectrum showed similar compounds in the browned product to be related with this photon emission. Superoxide and hydrogen peroxide contributed highly to this photon emission, and several redox compounds enhanced the photon intensity at appropriate concentrations. Our work suggests that the photon intensity was closely related to the reactive oxygen species (ROS) generated from the browned product, and this effect may be utilized to evaluate the function and quality of browned food. PMID:12353622

Iida, Tetsuo; Yoshiki, Yumiko; Someya, Shinich; Okubo, Kazuyoshi

2002-08-01

78

Production representation of partial wave scattering amplitudes and the f 0(600) particle  

NASA Astrophysics Data System (ADS)

The establishment of production representation of partial wave scattering amplitudes is reviewed in the context of quantum field theory. Its relation to the production representation, or Ning Hu representation in quantum mechanical scattering theory is pointed out. One of the most important application of the production representation is the physics of the f 0(600) and K(700) scalar hadron resonances, on which we also give a brief review. It is emphasized that all evidences accumulated so far are consistent with the picture that the f 0(600) meson is the chiral partner of the Nambu-Goldstone bosons in a linear realization of chiral symmetry.

Zheng, Han-Qing

2013-10-01

79

Inclusive D 0 and D*± production in neutral current deep inelastic ep scattering at HERA  

Microsoft Academic Search

First results on inclusivemathop {D^0 }limits^{( - )} and D*± production in neutral current deep inelastic ep scattering are reported using data collected by the H1 experiment at HERA in 1994. Differential cross sections are presented for both channels and are found to agree well with QCD predictions based on the boson gluon fusion process. A charm production cross section

C. Adloff; S. Aid; M. Anderson; V. Andreev; B. Andrieu; R.-D. Appuhn; C. Arndt; A. Babaev; J. Bähr; J. Bán; Y. Ban; P. Baranov; E. Barrelet; R. Barschke; W. Bartel; M. Barth; U. Bassler; H. P. Beck; H.-J. Behrend; A. Belousov; Ch. Berger; G. Bernardi; G. Bertrand-Coremans; M. Besançon; R. Beyer; P. Biddulph; P. Bispham; J. C. Bizot; V. Blobel; K. Borras; F. Botterweck; V. Boudry; A. Braemer; W. Braunschweig; V. Brisson; P. Bruel; D. Bruncko; C. Brune; R. Buchholz; L. Büngener; J. Bürger; F. W. Büsser; A. Buniatian; S. Burke; M. J. Burton; D. Calvet; A. J. Campbell; T. Carli; M. Charlet; D. Clarke; A. B. Clegg; B. Clerbaux; S. Cocks; J. G. Contreras; C. Cormack; J. A. Coughlan; A. Courau; M.-C. Cousinou; G. Cozzika; L. Criegee; D. G. Cussans; J. Cvach; S. Dagoret; J. B. Dainton; W. D. Dau; K. Daum; M. David; C. L. Davis; B. Delcourt; A. de Roeck; E. A. de Wolf; M. Dirkmann; P. Dixon; P. di Nezza; W. Dlugosz; C. Dollfus; J. D. Dowell; H. B. Dreis; A. Droutskoi; O. Dünger; H. Duhm; J. Ebert; T. R. Ebert; G. Eckerlin; V. Efremenko; S. Egli; R. Eichler; F. Eisele; E. Eisenhandler; E. Elsen; M. Erdmann; W. Erdmann; E. Evrard; A. B. Fahr; L. Favart; A. Fedotov; D. Feeken; R. Felst; J. Feltesse; J. Ferencei; F. Ferrarotto; K. Flamm; M. Fleischer; M. Flieser; G. Flügge; A. Fomenko; B. Fominykh; J. Formánek; J. M. Foster; G. Franke; E. Fretwurst; E. Gabathuler; K. Gabathuler; F. Gaede; J. Garvey; J. Gayler; M. Gebauer; H. Genzel; R. Gerhards; A. Glazov; U. Goerlach; L. Goerlich; N. Gogitidze; M. Goldberg; D. Goldner; K. Golec-Biernat; B. Gonzalez-Pineiro; I. Gorelov; C. Grab; H. Grässler; T. Greenshaw; R. K. Griffiths; G. Grindhammer; A. Gruber; C. Gruber; J. Haack; T. Hadig; D. Haidt; L. Hajduk; M. Hampel; W. J. Haynes; G. Heinzelmann; R. C. W. Henderson; H. Henschel; I. Herynek; M. F. Hess; K. Hewitt; W. Hildesheim; K. H. Hiller; C. D. Hilton; J. Hladký; K. C. Hoeger; M. Höppner; D. Hoffmann; T. Holtom; R. Horisberger; V. L. Hudgson; M. Hütte; M. Ibbotson; H. Itterbeck; A. Jacholkowska; C. Jacobsson; M. Jaffre; J. Janoth; T. Jansen; L. Jönsson; D. P. Johnson; H. Jung; P. I. P. Kalmus; M. Kander; D. Kant; R. Kaschowitz; U. Kathage; J. Katzy; H. H. Kaufmann; O. Kaufmann; M. Kausch; S. Kazarian; I. R. Kenyon; S. Kermiche; C. Keuker; C. Kiesling; M. Klein; C. Kleinwort; G. Knies; T. Köhler; J. H. Köhne; H. Kolanoski; F. Kole; S. D. Kolya; V. Korbel; M. Korn; P. Kostka; S. K. Kotelnikov; T. Krämerkämper; M. W. Krasny; H. Krehbiel; D. Krücker; A. Küpper; H. Küster; M. Kuhlen; T. Kurca; J. Kurzhöfer; D. Lacour; B. Laforge; R. Lander; M. P. J. Landon; W. Lange; U. Langenegger; J.-F. Laporte; A. Lebedev; F. Lehner; S. Levonian; G. Lindström; M. Lindstroem; J. Link; F. Linsel; J. Lipinski; B. List; G. Lobo; P. Loch; J. W. Lomas; G. C. Lopez; V. Lubimov; D. Lüke; N. Magnussen; E. Malinovski; S. Mani; R. Maracek; P. Marage; J. Marks; R. Marshall; J. Martens; G. Martin; R. Martin; H.-U. Martyn; J. Martyniak; T. Mavroidis; S. J. Maxfield; S. J. McMahon; A. Mehta; K. Meier; A. Meyer; H. Meyer; J. Meyer; P.-O. Meyer; A. Migliori; S. Mikocki; D. Milstead; J. Moeck; F. Moreau; J. V. Morris; E. Mroczko; D. Müller; G. Müller; K. Müller; P. Murín; V. Nagovizin; R. Nahnhauer; B. Naroska; Th. Naumann; I. Négri; P. R. Newman; D. Newton; H. K. Nguyen; T. C. Nicholls; F. Niebergall; C. Niebuhr; Ch. Niedzballa; H. Niggli; R. Nisius; G. Nowak; G. W. Noyes; M. Nyberg-Werther; M. Oakden; H. Oberlack; J. E. Olsson; D. Ozerov; P. Palmen; E. Panaro; A. Panitch; C. Pascaud; G. D. Patel; H. Pawletta; E. Peppel; E. Perez; J. P. Phillips; A. Pieuchot; D. Pitzl; G. Pope; S. Prell; K. Rabbertz; G. Rädel; P. Reimer; S. Reinshagen; H. Rick; V. Riech; J. Riedlberger; F. Riepenhausen; S. Riess; E. Rizvi; S. M. Robertson; P. Robmann; H. E. Roloff; R. Roosen; K. Rosenbauer; A. Rostovtsev; F. Rouse; C. Royon; K. Rüter; S. Rusakov; K. Rybicki; D. P. C. Sankey; P. Schacht; S. Schiek; S. Schleif; P. Schleper; W. von Schlippe; D. Schmidt; G. Schmidt; A. Schöning; V. Schröder; E. Schuhmann; B. Schwab; F. Sefkow; M. Seidel; R. Sell; A. Semenov; V. Shekelyan; I. Sheviakov; L. N. Shtarkov; G. Siegmon; U. Siewert; Y. Sirois; I. O. Skillicorn; P. Smirnov; J. R. Smith; V. Solochenko; Y. Soloviev; A. Specka; J. Spiekermann; S. Spielman; H. Spitzer; F. Squinabol; M. Steenbock; P. Steffen; R. Steinberg; H. Steiner; J. Steinhart; B. Stella; A. Stellberger; J. Stier; J. Stiewe; U. Stößlein; K. Stolze; U. Straumann; W. Struczinski; J. P. Sutton; S. Tapprogge; M. Tasevský; V. Tchernyshov; S. Tchetchelnitski; Tchetchelnitski J. Theissen; C. Thiebaux; G. Thompson; P. Truöl; K. Tzamariudaki; G. Tsipolitis; J. Turnau; J. Tutas; P. Uelkes; A. Usik; S. Valkár; A. Valkárová; C. Vallée; D. Vandenplas; P. van Esch; P. van Mechelen; Y. Vazdik; P. Verrecchia; G. Villet; K. Wacker; A. Wagener; M. Wagener; A. Walther

1996-01-01

80

Modulation of high sensitivity C-reactive protein by soluble receptor for advanced glycation end products  

Microsoft Academic Search

High sensitivity C-reactive protein (hs-CRP) is synthesized mainly by hepatocytes in response to tumor necrosis factor-alpha\\u000a (TNF-?), interleukin-1 (IL-1), and interleukin-6 (IL-6). The interaction of advanced glycation end products (AGEs) with the\\u000a receptor for advanced glycation end products (RAGE) increases the expression of the cytokines TNF-?, IL-1, and IL-6. Soluble\\u000a receptor for advanced glycation end products (sRAGE) competes with RAGE

Erick D. McNair; Calvin R. Wells; A. Mabood Qureshi; Rashpal Basran; Colin Pearce; Jason Orvold; Jacobus Devilliers; Kailash Prasad

2010-01-01

81

Heavy quark production in deep inelastic electron-nucleus scattering  

SciTech Connect

Heavy quark production has been very well studied over the last years both theoretically and experimentally. Theory has been used to study heavy quark production in ep collisions at HERA, in pp collisions at Tevatron and RHIC, in pA and dA collisions at RHIC, and in AA collisions at CERN-SPS and RHIC. However, to the best of our knowledge, heavy quark production in eA has received almost no attention. With the possible construction of a high energy electron-ion collider, updated estimates of heavy quark production are needed. We address the subject from the perspective of saturation physics and compute the heavy quark production cross section with the dipole model. We isolate shadowing and nonlinear effects, showing their impact on the charm structure function and on the transverse momentum spectrum.

Goncalves, V. P. [Instituto de Fisica e Matematica, Universidade Federal de Pelotas Caixa Postal 354, CEP 96010-090, Pelotas, RS (Brazil); Kugeratski, M. S. [Universidade Federal de Santa Catarina, Campus Universitario de Curitibanos, CEP 89520-000, Curitibanos, SC (Brazil); Navarra, F. S. [Instituto de Fisica, Universidade de Sao Paulo, C.P. 66318, 05315-970 Sao Paulo, SP (Brazil)

2010-06-15

82

Reactive oxygen product formation by human neutrophils as an early marker for biocompatibility of dialysis membranes.  

PubMed Central

Production of reactive oxygen intermediates (ROI) by neutrophils (PMN) in vivo was examined by a whole blood assay using dichlorofluorescein-diacetate (DCFH-DA) in 10 patients each dialysed consecutively with two different dialyser membranes. Haemodialysis (HD) with cuprophan membrane (CM) led to a significantly (P < 0.001) more pronounced ROI production by PMN (2.4 +/- 0.5-fold increase in intracellular oxidation of DCFH-DA) compared with HD with polysulfone membranes (PM; 1.5 +/- 0.2-fold). HD with CM induced a decrease in PMN count by about 90%, whereas PM induced a decrease by only 25% (P < 0.001). In CM patients maximal ROI production coincided with the nadir in PMN count. All patients dialysed with CM showed a clear increase in serum levels of Bb fragments, whereas PM-dialysed patients did not. In this respect, however, no clear time relationship was seen to the kinetics of ROI production, nor to the disappearance of neutrophils from the circulation. Evaluating a direct effect of the dialysis membranes on PMN demonstrated that incubation of neutrophils with hollow fibres of the CM but not of the PM in the absence of plasma induces significant ROI production by PMN. Our study thus indicates that ROI production by PMN during HD correlates to membrane biocompatibility. Furthermore, one might speculate that also independently from but perhaps in addition to complement activation, reactive oxygen products are critically involved in the generation of haemodialysis-associated neutrophil emigration.

Rosenkranz, A R; Templ, E; Traindl, O; Heinzl, H; Zlabinger, G J

1994-01-01

83

Dectin-1 activates Syk tyrosine kinase in a dynamic subset of macrophages for reactive oxygen production  

PubMed Central

Dectin-1 is a lectin receptor for ?-glucan that is important for innate macrophage recognition of fungi and contributes to phagocytosis, reactive oxygen production, and induction of inflammatory cytokines. The mechanisms by which Dectin-1 mediates intracellular signaling are just beginning to be defined. Spleen tyrosine kinase (Syk) is a protein tyrosine kinase that is critical for adaptive immune responses where it mediates signaling through B-cell receptors, T-cell receptors, and Fc receptors. Here we report that Dectin-1 activates Syk in macrophages and is important for Dectin-1-stimulated reactive oxygen production, but not for phagocytosis. Syk activation is restricted to a subpopulation of macrophages that is in equilibrium with cells that cannot activate the pathway. The proportion of macrophages using this signaling pathway can be modulated by cytokine treatment. Thus, Dectin-1 signaling reveals dynamic macrophage heterogeneity in inflammatory activation potential. (Blood. 2005;106:2543-2550)

Underhill, David M.; Rossnagle, Eddie; Lowell, Clifford A.; Simmons, Randi M.

2005-01-01

84

[Determination of anions in the products of ozonation of reactive dye by ion chromatography].  

PubMed

A method for the determination of anions in the degradation products of C. I. Reactive Red 120 by ozonation was investigated. The sample can be pretreated with a Dionex OnGuard P column, which has high selectivity for removing phenols, azo group-contaning compounds, aromatic carboxylic aicds etc. For the separation of organic and inorganic anions in the products, the anion exchange chromatograhy with gradient elution of NaOH was used. All the species were detected by both suppressed conductivity and UV absorbance detectors. The sulfate, oxalate, chloride, nitrate and formate could be identified even in very low concentration with ion chromatography, within 18 min, with the recoveries between 91.6% - 108.3%. The results indicate that the method is reliable, simple, rapid and especially sensitive. In combining with the determination results of conventional parameters of the solution of Reactive Red 120, a preliminary elucidation of the degradation mechanism PMID:16358701

Zhang, Fei-Fang; Liang, Xin-Miao; Zhang, Qing; Chen, Ji-Ping; Yediler, Ayfer; Kettrup, Antonius

2002-09-01

85

1?,25-Dihydroxyvitamin D3 Modulation of Adipocyte Reactive Oxygen Species Production  

Microsoft Academic Search

Objective: We have previously shown 1?,25-dihydroxyvitamin D3 [1?,25-(OH)2D3] to inhibit mitochondrial uncoupling protein 2 (UCP2) expression in adipocytes and that in vivo suppression of calcitriol levels with calcium-rich diets increases UCP2 expression. Because UCP2 plays a significant role in the clearance of reactive oxygen species (ROS), we studied the effect of calcitriol on ROS production and ROS-induced adipocyte proliferation.Research Methods

Xiaocun Sun; Michael B. Zemel

2007-01-01

86

Analysis of a reactive extraction process for biodiesel production using a lipase immobilized on magnetic nanostructures  

Microsoft Academic Search

Magnetic nanoparticles were prepared by coprecipitating Fe2+ and Fe3+ ions in a sodium hydroxide solution and used as support for lipase. The lipase-coated particles were applied in a reactive extraction process that allowed separation of the products formed during transesterification. Kinetics data for triolein and ethanol consumption during biodiesel (ethyl oleate) synthesis together with a thermodynamic phase equilibrium model (liquid–liquid)

K. J. Dussan; C. A. Cardona; O. H. Giraldo; L. F. Gutiérrez; V. H. Pérez

2010-01-01

87

A grid-mounted niobium body target for the production of reactive [18F]fluoride.  

PubMed

A small-volume grid-supported niobium target was constructed for the production of [18F]-fluoride on a CTI RDS 112 cyclotron. The inert properties of niobium metal have proven compatible with the superheated environment generated during proton irradiation. A grid support, constructed from aluminum, provides the necessary heat removal for high-power irradiations. The niobium and gird combination supplies reactive fluoride over an extended target lifetime. PMID:16368243

Nye, Jonathon A; Avila-Rodriguez, Miguel A; Nickles, Robert J

2005-12-20

88

A grid-mounted niobium body target for the production of reactive [ 18F]fluoride  

Microsoft Academic Search

A small-volume grid-supported niobium target was constructed for the production of [18F]-fluoride on a CTI RDS 112 cyclotron. The inert properties of niobium metal have proven compatible with the superheated environment generated during proton irradiation. A grid support, constructed from aluminum, provides the necessary heat removal for high-power irradiations. The niobium and gird combination supplies reactive fluoride over an extended

Jonathon A. Nye; Miguel A. Avila-Rodriguez; Robert J. Nickles

2006-01-01

89

The absence of reactive oxygen species production protects mice against bleomycin-induced pulmonary fibrosis  

Microsoft Academic Search

BACKGROUND: Reactive oxygen species and tissue remodeling regulators, such as metalloproteinases (MMPs) and their inhibitors (TIMPs), are thought to be involved in the development of pulmonary fibrosis. We investigated these factors in the fibrotic response to bleomycin of p47phox -\\/- (KO) mice, deficient for ROS production through the NADPH-oxidase pathway. METHODS: Mice are administered by intranasal instillation of 0.1 mg

Boris Manoury; Soazig Nenan; Olivier Leclerc; Isabelle Guenon; Elisabeth Boichot; Jean-Michel Planquois; Claude P Bertrand; Vincent Lagente

2005-01-01

90

Sources of Reactive Oxygen Species Production in Excitotoxin-Stimulated Cerebellar Granule Cells  

Microsoft Academic Search

Reactive oxygen species (ROS) production in rat cerebellar granule cells in the presence of the excitotoxinsN-methyl-d-aspartate (NMDA) and kainic acid (KA) and by the protein kinase C activator phorbol myristate acetate (PMA) was Ca2+-dependent and resulted in decreased cell viability. Exposure of stimulated cells to rotenone (a respiratory chain inhibitor) did not decrease ROS levels and did not affect short-term

Alexander A. Boldyrev; David O. Carpenter; Matthew J. Huentelman; Craig M. Peters; Peter Johnson

1999-01-01

91

Effect of caloric restriction on mitochondrial reactive oxygen species production and bioenergetics: reversal by insulin.  

PubMed

To gain insight into the antiaging mechanisms of caloric restriction (CR), mitochondria from liver tissue of male Brown Norway rats were used to study the effects of CR and insulin on mitochondrial reactive oxygen species production and bioenergetics. As assessed by hydrogen peroxide measurement, CR resulted in a decrease in the production rate of reactive oxygen species. This decrease was attributed to a decrease in protonmotive force in mitochondria from the CR animals. The decrease in protonmotive force resulted from an increase in proton leak activity and a concomitant decrease in substrate oxidation activity. Each of these effects of CR was reversed by subjecting CR animals to 2 wk of insulin treatment. To achieve continuous and stable insulin delivery, animals were placed under temporary halothane anesthesia and miniosmotic pumps were implanted subcutaneously. To gain further insight into how CR and insulin exerted its effects on mitochondrial bioenergetics, the effects of CR and insulin were quantified using modular metabolic control analysis. This analysis revealed that the effects of CR were transmitted through different reaction branches of the bioenergetic system, and insulin reversed the effects of CR by acting through the same branches. These results provide a plausible mechanism by which mitochondrial reactive oxygen species production is lowered by CR and a complete description of the effects of CR on mitochondrial bioenergetics. They also indicate that these changes may be due to lowered insulin concentrations and altered insulin signaling in the CR animal. PMID:12969875

Lambert, A J; Merry, B J

2003-09-11

92

IL-10 reduces Th2 cytokine production and eosinophilia but augments airway reactivity in allergic mice.  

PubMed

We investigated the effects of interleukin (IL)-10 administration on allergen-induced Th2 cytokine production, eosinophilic inflammation, and airway reactivity. Mice were sensitized by intraperitoneal injection of ragweed (RW) adsorbed to Alum and challenged by intratracheal instillation of the allergen. Sensitization and challenge with RW increased concentrations of IL-10 in bronchoalveolar lavage (BAL) fluid from undetectable levels to 60 pg/ml over 72 h. Intratracheal instillation of 25 ng of recombinant murine IL-10 at the time of RW challenge further elevated BAL fluid IL-10 concentration to 440 pg/ml but decreased BAL fluid IL-4, IL-5, and interferon-gamma levels by 40-85% and eosinophil numbers by 70% (P < 0.0001). Unexpectedly, the same IL-10 treatment increased airway reactivity to methacholine in spontaneously breathing mice that had been sensitized and challenged with RW (P < 0.001). IL-10 treatment in naive animals or RW-sensitized mice challenged with PBS failed to increase airway reactivity, demonstrating that IL-10 induces an increase in airway reactivity only when it is administered in conjunction with allergic sensitization and challenge. The results demonstrate that IL-10 reduces Th2 cytokine levels and eosinophilic inflammation but augments airway hyperreactivity. Thus, despite its potent anti-inflammatory activity, IL-10 could contribute to the decline in pulmonary function observed in asthma. PMID:10749743

van Scott, M R; Justice, J P; Bradfield, J F; Enright, E; Sigounas, A; Sur, S

2000-04-01

93

Charm Production in Deep-Inelastic Lepton-Hadron Scattering.  

National Technical Information Service (NTIS)

Contents: Introduction; Heavy quark coefficient functions at asymptotic values Q(sup 2) >> m(sup 2); Charm electroproduction in the four-flavour number scheme; Omicron (alpha(sup 2)(sub s)) corections to polarized heavy flavour production and Q(sup 2) >> ...

M. D. Buza

1997-01-01

94

Study of hard scattering processes in multihadron production from gammagamma collisions at LEP  

Microsoft Academic Search

The production of multihadronic states in gammagamma collisions at LEP has been studied with the DELPHI detector. The analyzed data correspond to an integrated luminosity of about 32pb-1, collected in the LEP runs of 1990 1992. Minimum bias data and a sample of events with jets at high p T have been selected under the requirement that no scattered electron

P. Abreu; Apeldoorn van G. W; T. Adye; E. E. Agasi; Roy Aleksan; G. D. Alekseev; P. Allport; S. Almehed; F. M. L. Almeida Junior; S. J. Alvsvaag; Ugo Amaldi; A. Andreazza; P. Antilogus; W.-D. Apel; R. J. Apsimon; Y. Arnoud; B. Åsman; J.-E. Augustin; A. Augustinus; Paul Baillon; P. Bambade; F. Barao; R. Barate; Guido Barbiellini; Dimitri Yuri Bardin; G. J. Barker; A. Baroncelli; O. Barring; J. A. Barrio; Walter Bartl; M. J. Bates; Marco Battaglia; M. Baubillier; K.-H. Becks; M. Begalli; P. Beilliere; Yu A Belokopytov; P. Beltran; Alberto C Benvenuti; M. Berggren; D. Bertrand; F. Bianchi; M. Bigi; M. S. Bilenky; P. Billoir; J. Bjarne; D. Bloch; J. Blocki; S. Blyth; V. Bocci; P. N. Bogolubov; T. Bolognese; M. Bonesini; W. Bonivento; P. S. L. Booth; G. Borisov; C. Bosio; B. Bostjancic; S. Bosworth; O. Botner; B. Bouquet; C. Bourdarios; T. J. V. Bowcock; M. Bozzo; S. Braibant; P. Branchini; K. D. Brand; R. A. Brenner; H. Briand; C. Bricman; L. Brillault; R. C. A. Brown; P. Bruckman; J.-M. Brunet; A. Budziak; L. Bugge; T. Buran; A. Buys; J. A. M. A. Buytaert; M. Caccia; M. Calvi; A. J. Camacho Rozas; R. Campion; T. Bamporesi; V. Canale; K. Cankocak; F. Cao; F. Carena; P. Carrilho; L. Carroll; R. Cases; M. V. Castillo Gimenez; A. Cattai; F. R. Cavallo; L. Cerrito; V. Chabaud; A. Chan; M. Chapkin; Ph. Charpentier; J. Chauveau; P. Checchia; G. A. Chelkov; L. Chevalier; P. Chliapnikov; V. Chorowicz; J. T. M. Chrin; V. Cindro; P. Collins; J. L. Contreras; R. Contri; E. Cortina; G. Cosme; F. Couchot; H. B. Crawley; D. Crennell; G. Crosetti; J. Cuevas Maestro; S. Czellar; E. Dahl-Jensen; J. Dahm; B. Dalmagne; M. Dam; G. Damgaard; E. Daubie; A. Daum; P. D. Dauncey; M. Davenport; J. Davies; J. da Silva; C. Defoix; P. Delpierre; N. Demaria; A. de Angelis; H. de Boeck; W. de Boer; S. de Brabandere; C. de Clerq; M. D. M. de Fez Laso; C. de La Vaissiere; B. de Lotto; A. de Min; L. de Paula; H. Dijkstra; Lucia Di Ciaccio; F. Djama; J. Dolbeau; M. Donszelmann; K. Doroba; M. Dracos; J. Drees; M. Dris; Y. Dufour; F. Dupont; D M Edsall; L.-O. Eek; R. Ehret; T. Ekelof; G. Ekspong; A. Elliot Peisert; M. Elsing; J.-P. Engel; N. Ershaidat; M. Espirito Santo; D. Fassouliotis; M. Feindt; A. Fenyuk; A. Ferrer; T. A. Filippas; A Filippas-Tassos; H. Foeth; E. Fokitis; F. Fontanelli; K. A. J. Forbes; F. Formenti; J.-L. Fousset; S. Francon; B J Franek; P. Frenkiel; D E C Fries; A. G. Frodesen; R. Fruhwirth; F. Fulda-Quenzer; H. Furstenau; J A Fuster; D. Gamba; M. Gandelman; C. Garcia; J. Garcia; C. Gaspar; U. Gasparini; Ph. Gavillet; E. N. Gazis; J.-P. Gerber; P. Giacomelli; D. Gillespie; R. Gokieli; B. Golob; V. M. Golovatyuk; J. J. Gomez Y Cadenas; Gian P Gopal; L. Gorn; M. Gorski; Valerio Gracco; F. Grard; E. Graziani; G. Grosdidier; B. Grossetete; P. Gunnarsson; J. Guy; U. Haedinger; F. Hahn; M. Hahn; S. Hahn; S. Haider; Z. Hajduk; A. Hakansson; A. Hallgren; U. Hamacher; G. Hamel de Monchenault; W. Hao; F. J. Harris; V. Hedberg; R. Henriques; J. J. Hernandez; J. A. Hernando; P. Herquet; H. Herr; T. L. Hessing; C. O. Higgins; E. Higon; H. J. Hilke; T. S. Hill; S. D. Hodgson; T. Hofmokl; S.-O. Holmgren; P. J. Holt; D. Holthuizen; P. F. Honore; M. Houlden; K. Huet; K. Hultqvist; P. Ioannou; P.-S. Iversen; J. N. Jackson; R. Jacobsson; P. Jalocha; G. Jarlskog; P. Jarry; B. Jean-Marie; E. K. Johansson; M. Jonker; L. Jonsson; P. Juillot; M. Kaiser; G. Kalkanis; G. Kalmus; F. Kapusta; M. Karlsson; E. Karvelas; S. Katsanevas; E. C. Katsoufis; R. Keranen; B. A. Khomenko; N. N. Khovanski; B. King; N. J. Kjaer; H. Klein; A. Klovning; P. Kluit; A. Koch-Mehrin; J. H. Koehne; B. Koene; P. Kokkinias; M. Koratzinos; K. Korcyl; A. V. Korytov; V. Kostioukhine; C. Kourkoumelis; O. Kouznetsov; P. H. Kramer; M. Krammer; C. Kreuter; J. Krolikowski; I. Kronkvist; W. Krupinski; W. Kucewicz; K. Kulka; K. Kurvinen; C. Lacasta; C. Lambropoulos; J. W. Lamsa; L. Lanceri; P. Langefeld; V. Lapin; I. Last; J.-P. Laugier; R. Lauhakangas; G. Leder; F. Ledroit; Y. Lemoigne; J. Lemonne; G. Lenzen; V. Lepeltier; E. Lieb; D. Liko; J. Lindgren; R. Lindner; A. Lipniacka; I. Lippi; B. Loerstad; M. Lokajicek; J. G. Loken; A. Lopez-Fernandez; M. A. Lopez Aguera; M. Los; D. Loukas; J. J. Lozano; P. Lutz; L. Lyons; G. Maehlum; J. Maillard; A. Maio; A. Maltezos; F. Mandl; J. Marco; B. Marechal; M. Margoni; J.-C. Marin; C. Mariotti; A. Markou; T. Maron; S. Marti; C. Martinez-Rivero; F. Martinez-Vidal; F. Matorras; C. Matteuzzi; G. Matthiae; M. Mazzucato; M. McCubbin; R. McKay; R. McNulty; J. Medbo; C. Meroni; W. T. Meyer; M. Michelotto; E. Migliore; I. Mikulec; L. Mirabito; W. A. Mitaroff; G. V. Mitselmakher; U. Mjoernmark; T. Moa; R. Moeller; K. Moenig; M. R. Monge; P. Morettini; H. Mueller; W. J. Murray; B. Muryn; G. Myatt; F. Naraghi; F. L. Navarria; P. Negri; S. Nemecek; W. Neumann; N. Neumeister; R. Nicolaidou

1994-01-01

95

Open charm production in deep inelastic scattering at next-to-leading order at HERA.  

SciTech Connect

An introduction and overview of charm production in deep inelastic scattering at HERA is given. The existing next-to-leading order perturbative QCD calculations are then reviewed, and key results are summarized. Finally, comparisons are made with the most recent HERA data, and unresolved issues are highlighted.

Harris, B. W.

1999-09-20

96

Production of ?° in the Coulomb field of nuclei by virtual photons from electron scattering  

NASA Astrophysics Data System (ADS)

We explore the cross section for ?° production by virtual photons from electron scattering, interacting with the Coulomb field of heavy nuclei. The same process with real photons, generally known as the Primakoff effect, has been used in the past to investigate the ?° lifetime. In the present work, virtual photons bring into focus the electromagnetic structure of the ???° vertex.

Hadjimichael, E.; Fallieros, S.

1989-04-01

97

Catalytic reactive separation system for energy-efficient production of cumene  

DOEpatents

The present invention relates to an atmospheric pressure, reactive separation column packed with a solid acid zeolite catalyst for producing cumene from the reaction of benzene with propylene. Use of this un-pressurized column, where simultaneous reaction and partial separation occur during cumene production, allow separation of un-reacted, excess benzene from other products as they form. This high-yielding, energy-efficient system allows for one-step processing of cumene, with reduced need for product purification. Reacting propylene and benzene in the presence of beta zeolite catalysts generated a selectivity greater than 85% for catalytic separation reactions at a reaction temperature of 115 degrees C and at ambient pressure. Simultaneously, up to 76% of un-reacted benzene was separated from the product; which could be recycled back to the reactor for re-use.

Buelna, Genoveva (Nuevo Laredo, MX); Nenoff, Tina M. (Albuquerque, NM)

2009-07-28

98

Coherent production of ? mesons in muon-carbon scattering at 150 and 100 GeV  

NASA Astrophysics Data System (ADS)

We have observed coherent production of ? mesons by muon scattering on carbon. The differential cross section falls steeply with increasing t (the square of the four-momentum transferred to the nucleus) and helicity is conserved in the s channel. Dominance by coherent production, as well as the radius of the carbon nucleus and the total ?-nucleus cross section derived from our measurements, are consistent with what is observed in other related processes.

Shambroom, W. D.; Gordon, B. A.; Loomis, W. A.; Pipkin, F. M.; Pordes, S. H.; Verhey, L. J.; Wilson, Richard; Anderson, H. L.; Fine, R. M.; Heisterberg, R. H.; Matis, H. S.; Mo, L. W.; Myrianthopoulos, L. C.; Wright, S. C.; Francis, W. R.; Hicks, R. G.; Kirk, T. B.; Bharadwaj, V. K.; Booth, N. E.; Kirkbride, G. I.; Quirk, T. W.; Skuja, A.; Williams, W. S.

1981-08-01

99

Interpolating and Approximating Scattered 3D-Data with Hierarchical Tensor Product B-Splines  

Microsoft Academic Search

In this note we describe surface reconstruction algorithms based on optimization techniques. The input are scattered 3D-data with specified topology. The surfaces constructed are tensor product B-splines. To achieve local detail and\\/or local fairness we make use of hierarchical tensor product B-splines. Interpolation as well as approximation problems are discussed. The problem of parameterizing a discrete point set which is

Gunther Greiner; Kai Hormann

1997-01-01

100

Inclusive D *± meson and associated dijet production in deep-inelastic scattering at HERA  

Microsoft Academic Search

Inclusive D*± production is measured in deep-inelastic ep scattering at HERA with the H1 detector. In addition, the production of dijets\\u000a in events with a D*± meson is investigated. The analysis covers values of photon virtuality 2 ? Q2 ? 100 GeV2 and of inelasticity 0.05?y?0.7. Differential cross sections are measured as a function of Q2 and x and of various

A. Aktas; V. Andreev; T. Anthonis; B. Antunovic; S. Aplin; A. Astvatsatourov; A. Baghdasaryan; S. Backovic; P. Baranov; E. Barrelet; W. Bartel; S. Baudrand; M. Beckingham; K. Begzsuren; O. Behnke; O. Behrendt; A. Belousov; N. Berger; J. C. Bizot; M.-O. Boenig; V. Boudry; I. Bozovic-Jelisavcic; J. Bracinik; G. Brandt; M. Brinkmann; V. Brisson; D. Bruncko; F. W. Büsser; A. Bunyatyan; G. Buschhorn; L. Bystritskaya; A. J. Campbell; K. B. Cantun Avila; F. Cassol-Brunner; K. Cerny; V. Cerny; V. Chekelian; A. Cholewa; J. G. Contreras; J. A. Coughlan; G. Cozzika; J. Cvach; J. B. Dainton; K. Daum; Y. de Boer; B. Delcourt; M. Del Degan; A. De Roeck; E. A. De Wolf; C. Diaconu; V. Dodonov; A. Dubak; G. Eckerlin; V. Efremenko; S. Egli; R. Eichler; F. Eisele; A. Eliseev; E. Elsen; S. Essenov; A. Falkewicz; P. J. W. Faulkner; L. Favart; A. Fedotov; R. Felst; J. Feltesse; J. Ferencei; L. Finke; M. Fleischer; G. Flucke; A. Fomenko; G. Franke; T. Frisson; E. Gabathuler; E. Garutti; J. Gayler; S. Ghazaryan; S. Ginzburgskaya; A. Glazov; I. Glushkov; L. Goerlich; M. Goettlich; N. Gogitidze; S. Gorbounov; M. Gouzevitch; C. Grab; T. Greenshaw; M. Gregori; B. R. Grell; G. Grindhammer; S. Habib; D. Haidt; M. Hansson; G. Heinzelmann; C. Helebrant; R. C. W. Henderson; H. Henschel; G. Herrera; M. Hildebrandt; K. H. Hiller; D. Hoffmann; R. Horisberger; A. Hovhannisyan; T. Hreus; S. Hussain; M. Jacquet; X. Janssen; V. Jemanov; L. Jönsson; D. P. Johnson; A. W. Jung; H. Jung; M. Kapichine; J. Katzy; I. R. Kenyon; C. Kiesling; M. Klein; C. Kleinwort; T. Klimkovich; T. Kluge; G. Knies; A. Knutsson; V. Korbel; P. Kostka; M. Kraemer; K. Krastev; J. Kretzschmar; A. Kropivnitskaya; K. Krüger; M. P. J. Landon; W. Lange; G. Lastovicka-Medin; P. Laycock; A. Lebedev; G. Leibenguth; V. Lendermann; S. Levonian; L. Lindfeld; K. Lipka; A. Liptaj; B. List; J. List; N. Loktionova; R. Lopez-Fernandez; V. Lubimov; A.-I. Lucaci-Timoce; H. Lueders; L. Lytkin; A. Makankine; E. Malinovski; P. Marage; L. Marti; M. Martisikova; H.-U. Martyn; S. J. Maxfield; A. Mehta; K. Meier; A. B. Meyer; H. Meyer; J. Meyer; V. Michels; S. Mikocki; I. Milcewicz-Mika; D. Mladenov; A. Mohamed; F. Moreau; A. Morozov; J. V. Morris; M. U. Mozer; K. Müller; P. Murín; K. Nankov; B. Naroska; T. Naumann; P. R. Newman; C. Niebuhr; A. Nikiforov; G. Nowak; K. Nowak; M. Nozicka; R. Oganezov; B. Olivier; J. E. Olsson; S. Osman; D. Ozerov; V. Palichik; I. Panagoulias; M. Pandurovic; T. Papadopoulou; C. Pascaud; G. D. Patel; H. Peng; E. Perez; D. Perez-Astudillo; A. Perieanu; A. Petrukhin; I. Picuric; S. Piec; D. Pitzl; R. Placakyte; B. Povh; P. Prideaux; A. J. Rahmat; N. Raicevic; P. Reimer; A. Rimmer; C. Risler; E. Rizvi; P. Robmann; B. Roland; R. Roosen; A. Rostovtsev; Z. Rurikova; S. Rusakov; F. Salvaire; D. P. C. Sankey; M. Sauter; E. Sauvan; S. Schmidt; S. Schmitt; C. Schmitz; L. Schoeffel; A. Schöning; H.-C. Schultz-Coulon; F. Sefkow; R. N. Shaw-West; I. Sheviakov; L. N. Shtarkov; T. Sloan; I. Smiljanic; P. Smirnov; Y. Soloviev; D. South; V. Spaskov; A. Specka; M. Steder; B. Stella; J. Stiewe; A. Stoilov; U. Straumann; D. Sunar; T. Sykora; V. Tchoulakov; G. Thompson; P. D. Thompson; T. Toll; F. Tomasz; D. Traynor; T. N. Trinh; P. Truöl; I. Tsakov; G. Tsipolitis; I. Tsurin; J. Turnau; E. Tzamariudaki; K. Urban; A. Usik; D. Utkin; A. Valkárová; C. Vallée; P. Van Mechelen; A. Vargas Trevino; Y. Vazdik; S. Vinokurova; V. Volchinski; K. Wacker; G. Weber; R. Weber; D. Wegener; C. Werner; M. Wessels; C. Wissing; R. Wolf; E. Wünsch; S. Xella; W. Yan; V. Yeganov; J. Žá?ek; J. Zálesák; Z. Zhang; A. Zhelezov; A. Zhokin; Y. C. Zhu; J. Zimmermann; T. Zimmermann; H. Zohrabyan; F. Zomer

2007-01-01

101

Inclusive D 0 and D * ± production in neutral current deep inelastic ep scattering at HERA  

Microsoft Academic Search

First results on inclusive$$\\\\mathop {D^0 }\\\\limits^{( - )} $$ andD*± production in neutral current deep inelasticep scattering are reported using data collected by the H1 experiment at HERA in 1994. Differential cross sections are presented\\u000a for both channels and are found to agree well with QCD predictions based on the boson gluon fusion process. A charm production\\u000a cross section for

C. Adloff; S. Aid; M. Anderson; V. Andreev; B. Andrieu; R.-D. Appuhn; C. Arndt; A. Babaev; J. Bähr; J. Bán; Y. Ban; P. Baranov; E. Barrelet; R. Barschke; W. Bartel; M. Barth; U. Bassler; H. P. Beck; H.-J. Behrend; A. Belousov; Ch. Berger; G. Bernardi; G. Bertrand-Coremans; M. Besançon; R. Beyer; P. Biddulph; P. Bispham; J. C. Bizot; V. Blobel; K. Borras; F. Botterweck; V. Boudry; A. Braemer; W. Braunschweig; V. Brisson; P. Bruel; D. Bruncko; C. Brune; R. Buchholz; L. Büngener; J. Bürger; F. W. Büsser; A. Buniatian; S. Burke; M. J. Burton; D. Calvet; A. J. Campbell; T. Carli; M. Charlet; D. Clarke; A. B. Clegg; B. Clerbaux; S. Cocks; J. G. Contreras; C. Cormack; J. A. Coughlan; A. Courau; M.-C. Cousinou; G. Cozzika; L. Criegee; D. G. Cussans; J. Cvach; S. Dagoret; J. B. Dainton; W. D. Dau; K. Daum; M. David; C. L. Davis; B. Delcourt; A. De Roeck; E. A. De Wolf; M. Dirkmann; P. Dixon; P. Di Nezza; W. Dlugosz; C. Dollfus; J. D. Dowell; H. B. Dreis; A. Droutskoi; O. Dünger; H. Duhm; J. Ebert; T. R. Ebert; G. Eckerlin; V. Efremenko; S. Egli; R. Eichler; F. Eisele; E. Eisenhandler; E. Elsen; M. Erdmann; W. Erdmann; E. Evrard; A. B. Fahr; L. Favart; A. Fedotov; D. Feeken; R. Felst; J. Feltesse; J. Ferencei; F. Ferrarotto; K. Flamm; M. Fleischer; M. Flieser; G. Flügge; A. Fomenko; B. Fominykh; J. Formánek; J. M. Foster; G. Franke; E. Fretwurst; E. Gabathuler; K. Gabathuler; F. Gaede; J. Garvey; J. Gayler; M. Gebauer; H. Genzel; R. Gerhards; A. Glazov; U. Goerlach; L. Goerlich; N. Gogitidze; M. Goldberg; D. Goldner; K. Golec-Biernat; B. Gonzalez-Pineiro; I. Gorelov; C. Grab; H. Grässler; T. Greenshaw; R. K. Griffiths; G. Grindhammer; A. Gruber; C. Gruber; J. Haack; T. Hadig; D. Haidt; L. Hajduk; M. Hampel; W. J. Haynes; G. Heinzelmann; R. C. W. Henderson; H. Henschel; I. Herynek; M. F. Hess; K. Hewitt; W. Hildesheim; K. H. Hiller; C. D. Hilton; J. Hladký; K. C. Hoeger; M. Höppner; D. Hoffmann; T. Holtom; R. Horisberger; V. L. Hudgson; M. Hütte; M. Ibbotson; H. Itterbeck; A. Jacholkowska; C. Jacobsson; M. Jaffre; J. Janoth; T. Jansen; L. Jönsson; D. P. Johnson; H. Jung; P. I. P. Kalmus; M. Kander; D. Kant; R. Kaschowitz; U. Kathage; J. Katzy; H. H. Kaufmann; O. Kaufmann; M. Kausch; S. Kazarian; I. R. Kenyon; S. Kermiche; C. Keuker; C. Kiesling; M. Klein; C. Kleinwort; G. Knies; T. Köhler; J. H. Köhne; H. Kolanoski; F. Kole; S. D. Kolya; V. Korbel; M. Korn; P. Kostka; S. K. Kotelnikov; T. Krämerkämper; M. W. Krasny; H. Krehbiel; D. Krücker; A. Küpper; H. Küster; M. Kuhlen; T. Kur?a; J. Kurzhöfer; D. Lacour; B. Laforge; R. Lander; M. P. J. Landon; W. Lange; U. Langenegger; J.-F. Laporte; A. Lebedev; F. Lehner; S. Levonian; G. Lindström; M. Lindstroem; J. Link; F. Linsel; J. Lipinski; B. List; G. Lobo; P. Loch; J. W. Lomas; G. C. Lopez; V. Lubimov; D. Lüke; N. Magnussen; E. Malinovski; S. Mani; R. Mara?ek; P. Marage; J. Marks; R. Marshall; J. Martens; G. Martin; R. Martin; H.-U. Martyn; J. Martyniak; T. Mavroidis; S. J. Maxfield; S. J. McMahon; A. Mehta; K. Meier; A. Meyer; H. Meyer; J. Meyer; P.-O. Meyer; A. Migliori; S. Mikocki; D. Milstead; J. Moeck; F. Moreau; J. V. Morris; E. Mroczko; D. Müller; G. Müller; K. Müller; P. Murín; V. Nagovizin; R. Nahnhauer; B. Naroska; Th. Naumann; I. Négri; P. R. Newman; D. Newton; H. K. Nguyen; T. C. Nicholls; F. Niebergall; C. Niebuhr; Ch. Niedzballa; H. Niggli; R. Nisius; G. Nowak; G. W. Noyes; M. Nyberg-Werther; M. Oakden; H. Oberlack; J. E. Olsson; D. Ozerov; P. Palmen; E. Panaro; A. Panitch; C. Pascaud; G. D. Patel; H. Pawletta; E. Peppel; E. Perez; J. P. Phillips; A. Pieuchot; D. Pitzl; G. Pope; S. Prell; K. Rabbertz; G. Rädel; P. Reimer; S. Reinshagen; H. Rick; V. Riech; J. Riedlberger; F. Riepenhausen; S. Riess; E. Rizvi; S. M. Robertson; P. Robmann; H. E. Roloff; R. Roosen; K. Rosenbauer; A. Rostovtsev; F. Rouse; C. Royon; K. Rüter; S. Rusakov; K. Rybicki; D. P. C. Sankey; P. Schacht; S. Schiek; S. Schleif; P. Schleper; W. von Schlippe; D. Schmidt; G. Schmidt; A. Schöning; V. Schröder; E. Schuhmann; B. Schwab; F. Sefkow; M. Seidel; R. Sell; A. Semenov; V. Shekelyan; I. Sheviakov; L. N. Shtarkov; G. Siegmon; U. Siewert; Y. Sirois; I. O. Skillicorn; P. Smirnov; J. R. Smith; V. Solochenko; Y. Soloviev; A. Specka; J. Spiekermann; S. Spielman; H. Spitzer; F. Squinabol; M. Steenbock; P. Steffen; R. Steinberg; H. Steiner; J. Steinhart; B. Stella; A. Stellberger; J. Stier; J. Stiewe; U. Stößlein; K. Stolze; U. Straumann; W. Struczinski; J. P. Sutton; S. Tapprogge; M. Taševský; V. Tchernyshov; S. Tchetchelnitski; Tchetchelnitski J. Theissen; C. Thiebaux; G. Thompson; P. Truöl; K. Tzamariudaki; G. Tsipolitis; J. Turnau; J. Tutas; P. Uelkes; A. Usik; S. Valkár; A. Valkárová; C. Vallée; D. Vandenplas; P. Van Esch; P. Van Mechelen; Y. Vazdik; P. Verrecchia; G. Villet; K. Wacker; A. Wagener; M. Wagener

1996-01-01

102

Strangeness production in deep-inelastic positron-proton scattering at HERA  

Microsoft Academic Search

Measurements of K0 meson and ? baryon production in deep-inelastic positron-proton scattering (DIS) are presented in the kinematic range 10 < Q2 < 70 GeV2 and 10?4 < x < 10?2. The measurements, obtained using the H1 detector at the HEPA collider, are discussed in the light of possible mechanisms for increased strangeness production at low Bjorken-x. Comparisons of the

S. Aid; M. Anderson; V. Andreev; B. Andrieu; R.-D. Appuhn; A. Babaev; J. Bähr; J. Bán; Y. Ban; P. Baranov; E. Barrelet; R. Barschke; W. Bartel; M. Barth; U. Bassler; H.-J. Behrend; A. Belousov; Ch. Berger; G. Bernardi; G. Bertrand-Coremans; M. Besançon; R. Beyer; P. Biddulph; P. Bispham; J. C. Bizot; V. Blobel; K. Borras; F. Botterweck; V. Boudry; A. Braemer; W. Braunschweig; V. Brisson; P. Bruel; D. Bruncko; C. Brune; R. Buchholz; L. Büngener; J. Bürger; F. W. Büsser; A. Buniatian; S. Burke; M. J. Burton; D. Calvet; A. J. Campbell; T. Carli; M. Charlet; D. Clarke; A. B. Clegg; B. Clerbaux; S. Cocks; J. G. Contreras; C. Cormack; J. A. Coughlan; A. Courau; M.-C. Cousinou; G. Cozzika; L. Criegee; D. G. Cussans; J. Cvach; S. Dagoret; J. B. Dainton; W. D. Dau; K. Daum; M. David; C. L. Davis; A. De Roeck; E. A. De Wolf; B. Delcourt; P. Di Nezza; M. Dirkmann; P. Dixon; W. Dlugosz; C. Dollfus; J. D. Dowell; H. B. Dreis; A. Droutskoi; O. Dünger; H. Duhm; J. Ebert; T. R. Ebert; G. Eckerlin; V. Efremenko; S. Egli; R. Eichler; F. Eisele; E. Eisenhandler; E. Elsen; M. Erdmann; W. Erdmann; E. Evrard; A. B. Fahr; L. Favart; A. Fedotov; D. Feeken; R. Felst; J. Feltesse; J. Ferencei; F. Ferrarotto; K. Flamm; M. Fleischer; M. Flieseer; G. Flügge; A. Fomenko; B. Fominykh; J. Formánek; J. M. Foster; G. Franke; E. Fretwurst; E. Gabathuler; K. Gabathuler; F. Gaede; J. Garvey; J. Gayler; M. Gebauer; H. Genzel; R. Gerhards; A. Glazov; U. Goerlach; L. Goerlich; N. Gogitidze; M. Goldberg; D. Goldner; K. Golec-Biernat; B. Gonzalez-Pineiro; I. Gorelov; C. Grab; H. Grässler; T. Greenshaw; R. K. Griffiths; G. Grindhammer; A. Gruber; C. Gruber; J. Haack; T. Hadig; D. Haidt; L. Hajduk; M. Hampel; W. J. Haynes; G. Heinzelmann; R. C. M. Henderson; H. Henschel; I. Herynek; M. F. Hess; K. Hewitt; W. Hildesheim; K. H. Hiller; C. D. Hilton; J. Hladký; K. C. Hoeger; M. Höppner; D. Hoffmann; T. Holtom; R. Horisberger; V. L. Hudgson; M. Hütte; M. Ibbotson; H. Itterbeck; A. Jacholkowska; C. Jacobsson; M. Jaffre; J. Janoth; T. Jansen; L. Jönsson; D. P. Johnson; H. Jung; P. I. P. Kalmus; M. Kander; D. Kant; R. Kaschowitz; U. Kathage; J. Katzy; H. H. Kaufmann; O. Kaufmann; S. Kazarian; I. R. Kenyon; S. Kermiche; C. Keuker; C. Kiesling; M. Klein; C. Kleinwort; G. Knies; T. Köhler; J. H. Köhne; F. Kole; S. D. Kolya; V. Korbel; M. Korn; P. Kostka; S. K. Kotelnikov; T. Krämerkämper; M. W. Krasny; H. Krehbiel; D. Krücker; H. Küster; M. Kuhlen; T. Kurca; J. Kurzhöfer; D. Lacour; B. Laforge; R. Lander; M. P. J. Landon; W. Lange; U. Langenegger; J.-F. Laporte; A. Lebedev; F. Lehner; S. Levonian; G. Lindström; M. Lindstroem; J. Link; F. Linsel; J. Lipinski; B. List; G. Lobo; J. W. Lomas; G. C. Lopez; V. Lubimov; D. Lüke; N. Magnussen; E. Malinovski; S. Mani; R. Maracek; P. Marage; J. Marks; R. Marshall; J. Martens; G. Martin; R. Martin; H.-U. Martyn; J. Martyniak; T. Mavroidis; S. J. Maxfield; S. J. McMahon; A. Mehta; K. Meier; A. Meyer; H. Meyer; J. Meyer; P.-O. Meyer; A. Migliori; S. Mikocki; D. Milstead; J. Moeck; F. Moreau; J. V. Morris; E. Mroczko; D. Müller; G. Müller; M. Müller; P. Murín; V. Nagovizin; R. Nahnhauer; B. Naroska; Th. Naumann; I. Négri; P. R. Newman; D. Newton; H. K. Nguyen; T. C. Nicholls; F. Niebergall; C. Niebuhr; Ch. Niedzballa; H. Niggli; R. Nisius; G. Nowak; G. W. Noyes; M. Nyberg-Werther; M. Oakden; H. Oberlack; J. E. Olsson; D. Ozerov; P. Palmen; E. Panaro; A. Panitch; C. Pascaud; G. D. Patel; H. Pawletta; E. Peppel; E. Perez; J. P. Phillips; A. Pieuchot; D. Pitzl; G. Pope; S. Prell; K. Rabbertz; G. Rädel; P. Reimer; S. Reinshagen; H. Rick; V. Riech; J. Riedlberger; F. Riepenhausen; S. Riess; E. Rizvi; S. M. Robertson; P. Robmann; H. E. Roloff; R. Roosen; K. Rosenbauer; A. Rostovtsev; F. Rouse; C. Royon; K. Rüter; S. Rusakov; K. Rybicki; D. P. C. Sankey; P. Schacht; S. Schiek; S. Schleif; P. Schleper; W. von Schlippe; D. Schmidt; G. Schmidt; A. Schöning; V. Schröder; E. Schuhmann; B. Schwab; F. Sefkow; M. Seidel; R. Sell; A. Semenov; V. Shekelyan; I. Sheviakov; L. N. Shtarkov; G. Siegmon; U. Siewert; Y. Sirois; I. O. Skillicorn; P. Smirnov; J. R. Smith; V. Solochenko; Y. Soloviev; A. Specka; J. Spiekermann; S. Spielman; H. Spitzer; F. Squinabol; M. Steenbock; P. Steffen; R. Steinberg; H. Steiner; J. Steinhart; B. Stella; A. Stellberger; J. Stier; J. Stiewe; U. Stößlein; K. Stolze; U. Straumann; W. Struczinski; J. P. Sutton; S. Tapporogge; M. Tasevský; V. Tchernyshov; S. Tchetchelnitski; J. Theissen; C. Thiebaux; G. Thompson; P. Truöl; G. Tsipolitis; J. Turnau; J. Tutas; P. Uelkes; A. Usik; S. Valkár; A. Valkárová; C. Vallée; P. Van Esch; P. Van Mechelen; D. Vandenplas; Y. Vazdik; P. Verrecchia; G. Villet; K. Wacker; A. Wagener; M. Wagener; A. Walther; B. Waugh; G. Weber; M. Weber; D. Wegener; A. Wegner; T. Wengler; M. Werner; L. R. West; T. Wilksen; S. Willard

1996-01-01

103

Diffractive hadron production in deep inelastic scattering off heavy nuclei and gluon saturation  

SciTech Connect

We calculate the cross section for diffractive hadron production in deep inelastic scattering off heavy nuclei in the framework of gluon saturation/color glass condensate. We analyze the kinematic region of the future Electron-Ion Collider. We argue that coherent and incoherent diffractive channels are very sensitive to the structure of the nuclear matter at low x. This expresses itself in a characteristic dependence of the cross sections on rapidity and transverse momentum of the produced hadron and on the nuclear weight. We also discuss dependence on the scattering angle and argue that both coherent and incoherent cross sections may be within experimental reach at Electron-Ion Collider.

Tuchin, Kirill; Wu Dajing [Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011 (United States)

2011-03-01

104

Why Black Hole Production in Scattering of Cosmic Ray Neutrinos Is Generically Suppressed  

SciTech Connect

It has been argued that neutrinos originating from ultrahigh energy cosmic rays can produce black holes deep in the atmosphere in models with TeV-scale quantum gravity. Such black-hole events could be observed at the Auger Observatory. However, any phenomenologically viable model with a low scale of quantum gravity must explain how to preserve protons from rapid decay. We argue that the suppression of proton decay will also suppress lepton-nucleon scattering and hence black-hole production by scattering of ultrahigh energy cosmic ray neutrinos in the atmosphere. We discuss explicitly the split fermion solution to the problem of fast proton decay.

Stojkovic, Dejan; Dai Dechang [Department of Physics, Case Western Reserve University, Cleveland, Ohio 44106-7079 (United States); Starkman, Glenn D. [Department of Physics, Case Western Reserve University, Cleveland, Ohio 44106-7079 (United States); Astrophysics Department, University of Oxford, Oxford, OX1 3RH (United Kingdom)

2006-02-03

105

Imaging the proton via hard exclusive production in diffractive pp scattering  

SciTech Connect

We discuss the prospects for probing Generalized Parton Distributions (GPDs) via exclusive production of a high-mass system (H = heavy quarkonium, di-photon, di-jet, Higgs boson) in diffractive pp scattering, pp -> p + H + p. In such processes the interplay of hard and soft interactions gives rise to a diffraction pattern in the final-state proton transverse momenta, which is sensitive to the transverse spatial distribution of partons in the colliding protons. We comment on the plans for diffractive pp measurements at RHIC and LHC. Such studies could complement future measurements of GPDs in hard exclusive ep scattering (JLab, COMPASS, EIC).

Charles Hyde; Leonid Frankfurt; Mark Strikman; Christian Weiss

2007-05-21

106

In vitro inhibitory effect of mesenchymal stem cells on zymosan-induced production of reactive oxygen species  

Microsoft Academic Search

\\u000a In vitro chemiluminescent test showed that human bone marrow mesenchymal stem cells and conditioned media dose-dependently inhibit\\u000a production of reactive oxygen species by macrophages: 50% inhibition of chemiluminescence (compared to biocontrol) was observed\\u000a at 1:1 mesenchymal stem cell\\/macrophage ratio or after addition of 20–25% conditioned media to the incubation medium. The\\u000a observed mechanism of inhibition of production of reactive oxygen

A. F. Tsyb; V. N. Petrov; A. G. Konoplyannikov; E. V. Saypina; L. A. Lepechina; S. Sh. Kalsina; I. V. Semenkova; E. V. Agaeva

2008-01-01

107

Computational simulation of reactive species production by methane-air DBD at high pressure and high temperature  

NASA Astrophysics Data System (ADS)

Computational simulations of a single streamer in DBD in lean methane-air mixture at pressure of 1 and 3 atm and temperature of 300 and 500 K were conducted for plasma-enhanced chemical reactions in a closed system. The effects of surrounding pressure and temperature are characterized for reactive species production by a DBD discharge. The results show that the production characteristics of reactive species are strongly influenced by the total gas number density and the higher concentration of reactive species are produced at higher pressure and lower gas temperature for a given initial reduced electric field.

Takana, H.; Tanaka, Y.; Nishiyama, H.

2012-01-01

108

Metabolism of phenol and hydroquinone to reactive products by macrophage peroxidase or purified prostaglandin H synthase  

SciTech Connect

Macrophages, an important cell-type of the bone marrow stroma, are possible targets of benzene toxicity because they contain relatively large amounts of prostaglandin H synthase (PHS), which is capable of metabolizing phenolic compounds to reactive species. PHS also catalyzes the production of prostaglandins, negative regulators of myelopoiesis. Studies indicate that the phenolic metabolites of benzene are oxidized in bone marrow to reactive products via peroxidases. With respect to macrophages, PHS peroxidase is implicated, as in vivo benzene-induced myelotoxicity is prevented by low doses of nonsteroidal anti-inflammatory agents, drugs that inhibit PHS. Incubations of either 14C-phenol or 14C-hydroquinone with a lysate of macrophages collected from mouse peritoneum (greater than 95% macrophages), resulted in an irreversible binding to protein that was dependent upon H2O2, incubation time, and concentration of radiolabel. Production of protein-bound metabolites from phenol or hydroquinone was inhibited by the peroxidase inhibitor aminotriazole. Protein binding from 14C-phenol also was inhibited by 8 microM hydroquinone, whereas binding from 14C-hydroquinone was stimulated by 5 mM phenol. The nucleophile cysteine inhibited protein binding of both phenol and hydroquinone and increased the formation of radiolabeled water-soluble metabolites. Similar to the macrophage lysate, purified PHS also catalyzed the conversion of phenol to metabolites that bound to protein and DNA; this activation was both H2O2- and arachidonic acid-dependent. These results indicate a role for macrophage peroxidase, possibly PHS peroxidase, in the conversion of phenol and hydroquinone to reactive metabolites and suggest that the macrophage should be considered when assessing the hematopoietic toxicity of benzene.

Schlosser, M.J.; Shurina, R.D.; Kalf, G.F. (Thomas Jefferson Univ., Philadelphia, PA (USA))

1989-07-01

109

Advanced glycation end products enhance reactive oxygen and nitrogen species generation in neutrophils in vitro.  

PubMed

Increased oxidative stress (OS) in diabetes mellitus is one of the major factors leading to diabetic pathology. However, the mediators and mechanism that provoke OS in diabetes is not fully understood, and it is possible that accumulation of advanced glycation end products (AGEs) formed secondary to hyperglycemic conditions may incite circulating polymorphonuclear neutrophils (PMN) to generate reactive oxygen species (ROS). In this report, we aim to investigate the effect of AGE on reactive oxygen and nitrogen species generation and subsequent OS in PMN. AGE-HSA exert dose- and time-dependent enhancement of ROS and reactive nitrogen intermediates (RNI) generation by PMN. Increased ROS and RNI generation were found to be mediated through the upregulation of NADPH oxidase and inducible nitric oxide synthase (iNOS), respectively, as evident from the fact that AGE-treated neutrophils failed to generate ROS and RNI in presence of diphenyleneiodonium, a flavoprotein inhibitor for both enzymes. Further increased generation of ROS and RNI ceased when the cells were incubated with anti-RAGE antibody suggesting the involvement of AGE-RAGE interaction. Also increased malondialdehyde (MDA) and protein carbonyl formation in AGE-exposed PMN suggest induction of OS by AGE. This study provides evidence that AGEs may play a key role in the induction of oxidative stress through the augmentation of PMN-mediated ROS and RNI generation and this may be in part responsible for development of AGE-induced diabetic pathology. PMID:22048812

Bansal, Savita; Siddarth, Manushi; Chawla, Diwesh; Banerjee, Basu D; Madhu, S V; Tripathi, Ashok K

2011-11-03

110

Reactivity of litter leachates from California oak woodlands in the formation of disinfection by-products.  

PubMed

Litter materials from forested watersheds can be a significant source of dissolved organic matter (DOM) to surface waters that can contribute to the formation of carcinogenic disinfection by-products (DBPs) during drinking-water chlorination. This study characterized the reactivity of DOM from litter leachates of representative vegetation in oak woodlands, a major plant community in the Foothill Region of California. Leachates from fresh and decomposed litter (duff) from two oak species, pine, and annual grasses were collected for an entire rainy season to evaluate their reactivity to form DBPs on chlorination. Relationships among specific ultraviolet absorbance (S?UVA), fluorescence index (FI), specific differential ultraviolet absorbance (S?UVA), specific chlorine demand (SCD), and the dissolved organic carbon:dissolved organic nitrogen (DOC:DON) ratio to the specific DBP formation potential (SDBP-FP) were examined. The DOM derived from litter materials had considerable reactivity in forming trihalomethanes (THMs) (1.80-3.49 mmol mol), haloacetic acid (HAAs) (1.62-2.76 mmol mol(-1)), haloacetonitriles (HANs) (0.12-0.37 mmol mol(-1)), and chloral hydrate (CHD) (0.16-0.28 mmol mol). These values are comparable to other identified watershed sources of DBP precursors reported for the California Delta, such as wetlands and organic soils. Vegetation type and litter decomposition stage (fresh litter versus 1-5 yr-old duff) were key factors that determined characteristics of DOM and their reactivity to form DBPs. Pine litter had significantly lower specific THM formation potential compared with oak and grass, and decomposed duff had a greater DON content, which is a precursor of HANs and other nitrogenous DBPs. The S?UVA and SDBP-FP were temporally variable and dependent on vegetation type, degree of decomposition, and environmental conditions. Among the optical properties of DOM, S?UVA was the only parameter that was consistently correlated with SDBP-FP. PMID:21869524

Chow, Alex T; O'Geen, Anthony T; Dahlgren, Randy A; Díaz, Francisco J; Wong, Kin-Hang; Wong, Po-Keung

111

Reactive scattering of H2 from Cu(100): Comparison of dynamics calculations based on the specific reaction parameter approach to density functional theory with experiment  

NASA Astrophysics Data System (ADS)

We present new experimental and theoretical results for reactive scattering of dihydrogen from Cu(100). In the new experiments, the associative desorption of H2 is studied in a velocity resolved and final rovibrational state selected manner, using time-of-flight techniques in combination with resonance-enhanced multi-photon ionization laser detection. Average desorption energies and rotational quadrupole alignment parameters were obtained in this way for a number of (v = 0, 1) rotational states, v being the vibrational quantum number. Results of quantum dynamics calculations based on a potential energy surface computed with a specific reaction parameter (SRP) density functional, which was derived earlier for dihydrogen interacting with Cu(111), are compared with the results of the new experiments and with the results of previous molecular beam experiments on sticking of H2 and on rovibrationally elastic and inelastic scattering of H2 and D2 from Cu(100). The calculations use the Born-Oppenheimer and static surface approximations. With the functional derived semi-empirically for dihydrogen + Cu(111), a chemically accurate description is obtained of the molecular beam experiments on sticking of H2 on Cu(100), and a highly accurate description is obtained of rovibrationally elastic and inelastic scattering of D2 from Cu(100) and of the orientational dependence of the reaction of (v = 1, j = 2 - 4) H2 on Cu(100). This suggests that a SRP density functional derived for H2 interacting with a specific low index face of a metal will yield accurate results for H2 reactively scattering from another low index face of the same metal, and that it may also yield accurate results for H2 interacting with a defected (e.g., stepped) surface of that same metal, in a system of catalytic interest. However, the description that was obtained of the average desorption energies, of rovibrationally elastic and inelastic scattering of H2 from Cu(100), and of the orientational dependence of reaction of (v = 0, j = 3 - 5, 8) H2 on Cu(100) compares less well with the available experiments. More research is needed to establish whether more accurate SRP-density functional theory dynamics results can be obtained for these observables if surface atom motion is added to the dynamical model. The experimentally and theoretically found dependence of the rotational quadrupole alignment parameter on the rotational quantum number provides evidence for rotational enhancement of reaction at low translational energies.

Sementa, L.; Wijzenbroek, M.; van Kolck, B. J.; Somers, M. F.; Al-Halabi, A.; Busnengo, H. F.; Olsen, R. A.; Kroes, G. J.; Rutkowski, M.; Thewes, C.; Kleimeier, N. F.; Zacharias, H.

2013-01-01

112

Jet production in high Q 2 deep-inelastic ep scattering at HERA  

Microsoft Academic Search

Two-jet production in deep-inelastic electron-proton scattering has been studied for 160< Q 2<1280 GeV2, 0.01< x<0.1 and 0.04< y<0.95 with the ZEUS detector at HERA. The kinematic properties of the jets and the jet production rates are presented. The partonic scaling variables of the two-jet system and the rate of two-jet production are compared to perturbative next-to-leading order QCD calculations.

M. Derrick; D. Krakauer; S. Magill; D. Mikunas; B. Musgrave; J. Repond; R. Stanek; R. L. Talaga; H. Zhang; R. Avad; G. Bari; M. Basile; L. Bellagamba; D. Boscherini; A. Bruni; G. Bruni; P. Bruni; G. Cara Romeo; G. Castellini; M. Chiarini; L. Cifarelli; F. Cindolo; A. Contin; M. Corradi; I. Gialas; P. Giusti; G. Iacobucci; G. Laurenti; G. Levi; A. Margotti; T. Massam; R. Nania; C. Nemoz; E. Palmonari; A. Polini; G. Sartorelli; R. Timellini; Y. Zamora Garcia; A. Zichichi; A. Bargende; J. Crittenden; K. Desch; B. Diekmann; T. Doeker; M. Eckert; L. Feld; A. Frey; M. Geerts; G. Geitz; M. Grothe; T. Haas; H. Hartmann; D. Haun; K. Heinloth; E. Hilger; H.-P. Jakob; U. F. Katz; S. M. Mari; A. Mass; S. Mengel; J. Mollen; E. Paul; Ch. Rembser; R. Schattevoy; D. Schramm; J. Stamm; R. Wedemeyer; S. Campbell-Robson; A. Cassidy; N. Dyce; B. Foster; S. George; R. Gilmore; G. P. Heath; H. F. Heath; T. J. Llewellyn; C. J. S. Morgado; D. J. P. Norman; J. A. O'Mara; R. I. Tapper; S. S. Wilson; R. Yoshida; R. R. Rau; M. Arneodo; L. Iannotti; M. Schioppa; G. Susinno; A. Bernstein; A. Caldwell; J. A. Parsons; S. Ritz; F. Sciulli; P. B. Straub; L. Wai; S. Yang; Q. Zhu; P. Borzemski; J. Chwastowski; A. Eskreys; K. Piotrzkowski; M. Zachara; L. Zawiejski; L. Adamczyk; B. Bednarek; K. Eskreys; K. Jelen; D. Kisielewska; T. Kowalski; E. Rulikowska-Zarebska; L. Suszycki; J. Zajac; A. Kotanski; M. Przybycien; I. A. T. Bauerdick; U. Behrens; H. Beier; J. K. Bienlein; C. Coldewey; O. Deppe; K. Desler; G. Drews; M. Flasinski; D. J. Gilkinson; C. Glasman; P. Göttlicher; J. Große-Knetter; B. Gutjahr; W. Hain; D. Hasell; H. Heßling; H. Hultschig; Y. Iga; P. Joos; M. Kasemann; R. Klanner; W. Koch; L. Köpke; U. Kötz; H. Kowalski; J. Labs; A. Ladage; B. Löhr; M. Löwe; D. Lüke; O. Manczak; J. S. T. Ng; S. Nickel; D. Notz; K. Ohrenberg; M. Roco; M. Rohde; J. Roldán; U. Schneekloth; W. Schulz; F. Selonke; E. Stiliaris; B. Surrow; T. Voß; D. Westphal; G. Wolf; C. Youngman; J. F. Zhou; H. J. Grabosch; A. Kharchilava; A. Leich; M. Mattingly; A. Meyer; S. Schlenstedt; N. Wulff; G. Barbagli; P. Pelfer; G. Anzivino; G. Maccarrone; S. de Pasquale; L. Votano; A. Bamberger; S. Eisenhardt; A. Freidhof; S. Söldner-Rembold; J. Schroeder; T. Trefzger; N. H. Brook; P. J. Bussey; A. T. Doyle; I. Fleck; D. H. Saxon; M. L. Utley; A. S. Wilson; A. Dannemann; U. Holm; D. Horstmann; T. Neumann; R. Sinkus; K. Wick; E. Badura; B. D. Burow; L. Hagge; E. Lohrmann; J. Mainusch; J. Milewski; M. Nakahata; N. Pavel; G. Poelz; W. Schott; F. Zetsche; T. C. Bacon; I. Butterworth; E. Gallo; V. L. Harris; B. Y. H. Hung; K. R. Long; D. B. Miller; P. P. O. Morawitz; A. Prinias; J. K. Sedgbeer; A. F. Whitfield; U. Mallik; E. McCliment; M. Z. Wang; S. M. Wang; J. T. Wu; Y. Zhang; P. Cloth; D. Filges; S. H. An; S. M. Hong; S. W. Nam; S. K. Park; M. H. Suh; S. H. Yon; R. Imlay; S. Kartik; H.-J. Kim; R. R. McNeil; W. Metcalf; V. K. Nadendla; F. Barreiro; G. Cases; R. Graciani; J. M. Hernández; L. Hervás; L. Labarga; J. Del Peso; J. Puga; J. Terron; J. F. de Trocóniz; G. R. Smith; F. Corriveau; D. S. Hanna; J. Hartmann; L. W. Hung; J. N. Lim; C. G. Matthews; P. M. Patel; L. E. Sinclair; D. G. Stairs; M. St. Laurent; R. Ullmann; G. Zacek; V. Bashkirov; B. A. Dolgoshein; A. Stifutkin; G. L. Bashindzhagyan; P. F. Ermolov; L. K. Gladilin; Y. A. Golubkov; V. D. Kobrin; V. A. Kuzmin; A. S. Proskuryakov; A. A. Savin; L. M. Shcheglova; A. N. Solomin; N. P. Zotov; M. Botje; F. Chlebana; A. Dake; J. Engelen; M. de Kamps; P. Kooijman; A. Kruse; H. Tiecke; W. Verkerke; M. Vreeswijk; L. Wiggers; E. de Wolf; R. van Woudenberg; D. Acosta; B. Bylsma; L. S. Durkin; K. Honscheid; C. Li; T. Y. Ling; K. W. McLean; W. N. Murray; I. H. Park; T. A. Romanowski; R. Seidlein; D. S. Bailey; G. A. Blair; A. Byrne; R. J. Cashmore; A. M. Cooper-Sarkar; D. Daniels; R. C. E. Devenish; N. Harnew; M. Lancaster; P. E. Luffman; L. Lindemann; J. D. McFall; C. Nath; V. A. Noyes; A. Quadt; H. Uijterwaal; R. Walczak; F. F. Wilson; T. Yip; G. Abbiendi; A. Bertolin; R. Brugnera; R. Carlin; F. Dal Corso; M. de Giorgi; U. Dosselli; S. Limentani; M. Morandin; M. Posocco; L. Stanco; R. Stroili; C. Voci; J. Bulmahn; J. M. Butterworth; R. G. Feild; B. Y. Oh; J. J. Whitmore; G. D'Agostini; G. Marini; A. Nigro; E. Tassi; J. C. Hart; N. A. McCubbin; K. Prytz; T. P. Shah; T. L. Short; L. Barberis; N. Cartiglia; T. Dubbs; C. Heusch; M. van Hook; B. Hubbard; W. Lockman; J. T. Rahn; H. F.-W. Sadrozinski; A. Seiden; J. Biltzinger; R. J. Seifert; A. H. Walenta; G. Zech; H. Abramowicz; G. Briskin; S. Dagan; A. Levy; T. Hasegawa; M. Hazumi; T. Ishii; M. Kuze; S. Mine; Y. Nagasawa; M. Nakao; I. Suzuki; K. Tokushuku; S. Yamada; Y. Yamazaki; M. Chiba; R. Hamatsu; T. Hirose; K. Homma; S. Kitamura; Y. Nakamitsu; K. Yamauchi; R. Cirio; M. Costa; M. I. Ferrero; L. Lamberti; S. Maselli; C. Peroni; R. Sacchi

1995-01-01

113

Multiple scattering effects on inclusive particle production in the large-x regime  

NASA Astrophysics Data System (ADS)

We study the multiple scattering effects on inclusive particle production in p+A and ?+A collisions. Specifically, we concentrate on the region where the parton momentum fraction in the nucleus x˜O(1) and incoherent multiple interactions are relevant. By taking into account both initial-state and final-state double scattering, we derive the nuclear size-enhanced power corrections to the differential cross section for single inclusive hadron production in p+A and ?+A reactions, and for prompt photon production in p+A reactions. We find that the final result can be written in a simple compact form in terms of four-parton correlation functions, in which the second-derivative, first-derivative and nonderivative terms of the correlation distributions share the same hard-scattering functions. We expect our result to be especially relevant for understanding the nuclear modification of particle production in the backward rapidity regions in p+A and e+A collisions.

Kang, Zhong-Bo; Vitev, Ivan; Xing, Hongxi

2013-09-01

114

Dynamical model of coherent pion production in neutrino-nucleus scattering  

SciTech Connect

We study coherent pion production in neutrino-nucleus scattering in the energy region relevant to neutrino oscillation experiments of current interest. Our approach is based on the combined use of the Sato-Lee model of electroweak pion production on a nucleon and the {Delta}-hole model of pion-nucleus reactions. Thus we develop a model that describes pion-nucleus scattering and electroweak coherent pion production in a unified manner. Numerical calculations are carried out for the case of the {sup 12}C target. All the free parameters in our model are fixed by fitting to both total and elastic differential cross sections for pi-{sup 12}C scattering. Then we demonstrate the reliability of our approach by comparing our prediction for coherent pion photoproductions with the data. Finally, we calculate total and differential cross sections for neutrino-induced coherent pion production, and some of the results are compared with recent data from K2K, SciBooNE, and MiniBooNE. We also study the effect of nonlocality of {Delta} propagation in the nucleus and compare the elementary amplitudes used in different microscopic calculations.

Nakamura, S. X. [Instituto de Fisica, Universidade de Sao Paulo, C.P. 66318, 05315-970 Sao Paulo, SP (Brazil); Sato, T. [Department of Physics, Osaka University, Toyonaka, Osaka 560-0043 (Japan); Lee, T.-S. H. [Physics Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States); Szczerbinska, B. [Dakota State University, College of Arts and Sciences, Madison, SD 57042-1799 (United States); Kubodera, K. [Department of Physics and Astronomy, University of South Carolina, Columbia, SC 29208 (United States)

2010-03-15

115

Universal Quantification of Structurally Diverse Natural Products Using an Evaporative Light Scattering Detector  

PubMed Central

A lack of good methods for absolute quantification of natural products has limited the accuracy of high-throughput screening. Many currently used methods for quantification are either too slow or not amenable to the structural diversity of natural products. Recent developments in low-temperature evaporative light scattering detectors (ELSD-LT) have overcome several historical limitations of ELSDs, including analyte decomposition and low sensitivity. Primarily, ELSDs have been used for relative quantification and detection of compounds that lack a UV chromophore. In this study, we employ an ELSD-LT for absolute quantification of natural products. Calibration curves were constructed using a weighted least-squares analysis for a diverse set of natural products and other compounds. An average calibration curve was evaluated for the “universal” quantification of natural products. Optimization of ELSD-LT hardware and parameters improved sensitivity and throughput and established the utility of ELSD-LT for quantification of large natural product libraries.

2012-01-01

116

Ozone production and reactive nitrogen chemistry during the 2008 Beijing Olympic Games  

NASA Astrophysics Data System (ADS)

Measurements of ozone, peroxyacetyl nitrate (PAN), and related pollutants (NOx, NOy, NMHCs, and carbonyls) were conducted at an urban/suburban site in Beijing before, during, and after the 2008 Beijing Olympics. The data are analyzed to examine their responses to the strict pollution control measures in Beijing and to gain insight into ozone-precursor photochemistry and reactive nitrogen speciation. Approximately 40% of the study days had ozone pollution with the maximum hourly ozone concentration exceeding 100 ppbv. The pollution levels were relatively low during the Games (Aug 8th - 24th), mainly due to weather conditions (rainfalls and northerly winds). Elevated levels of PAN were frequently observed with a peak concentration of up to 9.34 ppbv and a PAN/O3 ratio of 0.055 ppbv/ppbv. Ozone production efficiencies (OPE) derived from the correlation of O3/Ox versus NOz were in the range of 2-5 ppbv/ppbv. The results suggested a VOCs-limited regime for ozone production. PAN accounted for a relatively high fraction (20 - 40%) of NOz during photochemical episodes. The sources of reactive nitrogen are discussed in relation to wind flow and to other air pollutants.

Xue, L.; Wang, T.; Gao, J.; Wang, X.; Gao, X.; Nie, W.; Ding, A.; Zhang, Q.; Wang, W.

2009-12-01

117

CD69 downregulates autoimmune reactivity through active transforming growth factor-? production in collagen-induced arthritis  

PubMed Central

CD69 is induced after activation of leukocytes at inflammatory sites, but its physiological role during inflammation remains unknown. We explored the role of CD69 in autoimmune reactivity by analyzing a model of collagen-induced arthritis (CIA) in WT and CD69-deficient mice. CD69–/– mice showed higher incidence and severity of CIA, with exacerbated T and B cell immune responses to type II collagen. Levels of TGF-?1 and TGF-?2, which act as protective agents in CIA, were reduced in CD69–/– mice inflammatory foci, correlating with the increase in the proinflammatory cytokines IL-1? and RANTES. Local injection of blocking anti–TGF-? antibodies increased CIA severity and proinflammatory cytokine mRNA levels in CD69+/+ but not in CD69–/– mice. Moreover, in vitro engagement of CD69 induced total and active TGF-?1 production in Concanavalin A–activated splenocyte subsets, mouse and human synovial leukocytes, and Jurkat stable transfectants of human CD69 but not in the parental CD69 negative cell line. Our results show that CD69 is a negative modulator of autoimmune reactivity and inflammation through the synthesis of TGF-?, a cytokine that in turn downregulates the production of various proinflammatory mediators.

Sancho, David; Gomez, Manuel; Viedma, Fernando; Esplugues, Enric; Gordon-Alonso, Monica; Angeles Garcia-Lopez, Maria; de la Fuente, Hortensia; Martinez-A, Carlos; Lauzurica, Pilar; Sanchez-Madrid, Francisco

2003-01-01

118

Ellagic acid protects hepatocytes from damage by inhibiting mitochondrial production of reactive oxygen species.  

PubMed

The aim of this experiment is to investigate the antioxidative and antiapoptotic roles of ellagic (EA) acid in in vitro and in in vivo experiment. We measured protective properties of EA against oxidative stress-induced hepatocyte damage in vitro and Concanavalin (ConA)-induced liver damage in vivo. EA, a potent antioxidant, exhibited protective properties against oxidative stress-induced hepatocyte damage by preventing vitamin k3 (VK3)-induced reactive oxygen species (ROS) productions, apoptotic and necrotic cellular damage and mitochondrial depolarization, which is a main cause of ROS production. EA also protects against cell death and elevation of glutathione (GSH), alanine transaminase (ALT) and asparatate transaminase (AST) in Con A-induced fulminant liver damage in mice. These results show that antioxidant and cytoprotective properties of EA prevent liver damage induced by various type of oxidative stress. PMID:20347566

Hwang, Jung Me; Cho, Jin Sook; Kim, Tae Hyeon; Lee, Young Ik

2009-10-23

119

Deep inelastic scattering and prompt photon production within the framework of the quark Reggeization hypothesis  

SciTech Connect

We study ep deep inelastic scattering and the inclusive production of prompt photon within the framework of the quasi-multi-Regge-kinematic approach, applying the quark Reggeization hypothesis. We describe structure functions F{sub 2} and F{sub L} supposing that a virtual photon scatters on a Reggeized quark from a proton, via the effective gamma-Reggeon-quark vertex. It is shown that the main mechanism of the inclusive prompt photon production in pp collisions is the fusion of a Reggeized quark and a Reggeized antiquark into a photon, via the effective Regeon-Reggeon-gamma vertex. We describe the inclusive photon transverse momentum spectra measured by the CDF and D0 Collaborations within errors and without free parameters, using the Kimber-Martin-Ryskin unintegrated quark and gluon distribution functions in a proton.

Saleev, V. A. [Samara State University, Ac. Pavlov St. 1, 443011 Samara (Russian Federation)

2008-08-01

120

Photoreactivity of carboxylated single-walled carbon nanotubes in sunlight: reactive oxygen species production in water.  

PubMed

Very limited information exists on transformation processes of carbon nanotubes in the natural aquatic environment. Because the conjugated pi-bond structure of these materials is efficient in absorbing sunlight, photochemical transformations are a potential fate process with reactivity predicted to vary with their diameter, chirality, number and type of defects, functionalization, residual metal catalyst and amorphous carbon content, and with the composition of the water, including the type and composition of materials that act to disperse them into the aqueous environment. In this study, the photochemical reactions involving colloidal dispersions of carboxylated single-walled carbon nanotubes (SWNT-COOH) in sunlight were examined. Production of reactive oxygen species (ROS) during irradiation occurs and is evidence for potential further phototransformation and may be significant in assessing their overall environmental impacts. In aerated samples exposed to sunlight or to lamps that emit light only within the solar spectrum, the probe compounds, furfuryl alcohol (FFA), tetrazolium salts (NBT2+ and XTT), and p-chlorobenzoic acid (pCBA), were used to indicate production of 1O2, O2.-, and .OH, respectively. All three ROS were produced in the presence of SWNT-COOH and molecular oxygen (3O2). 1O2 production was confirmed by observing enhanced FFA decay in deuterium oxide, attenuated decay of FFA in the presence of azide ion, and the lack of decay of FFA in deoxygenated solutions. Photogeneration of O2.- and .OH was confirmed by applying superoxide dismutase (SOD) and tert-butanol assays, respectively. In air-equilibrated suspensions, the loss of 0.2 mM FFA in 10 mg/L SWNT-COOH was approximately 85% after 74 h. Production of 1O2 was not dependent on pH from 7 to 11; however photoinduced aggregation was observed at pH 3. PMID:20687543

Chen, Chia-Ying; Jafvert, Chad T

2010-09-01

121

Muon production in low-energy electron-nucleon and electron-nucleus scattering  

Microsoft Academic Search

Recently, muon production in electron-proton scattering has been suggested as a possible candidate reaction for the identification of lepton-flavor violation due to physics beyond the standard model. Here we point out that the standard-model processes epp{sub }{sub e} and epen{sup +}{sub } can cloud potential beyond-the-standard-model signals in ep collisions. We find that standard-model epX cross sections exceed those from

Prashanth Jaikumar; Daniel R. Phillips; Lucas Platter; Madappa Prakash

2007-01-01

122

Study of hard scattering processes in multihadron production from ?? collisions at LEP  

Microsoft Academic Search

The production of multihadronic states in ?? collisions at LEP has been studied with the DELPHI detector. The analyzed data correspond to an integrated luminosity of about 32pb-1, collected in the LEP runs of 1990–1992. Minimum bias data and a sample of events with jets at highpT have been selected under the requirement that no scattered electron or positron is

P. Abreu; W. Adam; T. Adye; E. Agasi; R. Aleksan; G. D. Alekseev; P. Allport; S. Almehed; F. M. L. Almeida Junior; S. J. Alvsvaag; U. Amaldi; A. Andreazza; P. Antilogus; W.-D. Apel; R. J. Apsimon; Y. Arnoud; B. Åsman; J.-E. Augustin; A. Augustinus; P. Baillon; P. Bambade; F. Barao; R. Barate; G. Barbiellini; D. Y. Bardin; G. J. Barker; A. Baroncelli; O. Barring; J. A. Barrio; W. Bartl; M. J. Bates; M. Battaglia; M. Baubillier; K.-H. Becks; M. Begalli; P. Beilliere; Yu. Belokopytov; P. Beltran; A. C. Benvenuti; M. Berggren; D. Bertrand; F. Bianchi; M. Bigi; M. S. Bilenky; P. Billoir; J. Bjarne; D. Bloch; J. Blocki; S. Blyth; V. Bocci; P. N. Bogolubov; T. Bolognese; M. Bonesini; W. Bonivento; P. S. L. Booth; G. Borisov; C. Bosio; B. Bostjancic; S. Bosworth; O. Botner; B. Bouquet; C. Bourdarios; T. J. V. Bowcock; M. Bozzo; S. Braibant; P. Branchini; K. D. Brand; R. A. Brenner; H. Briand; C. Bricman; L. Brillault; R. C. A. Brown; P. Bruckman; J.-M. Brunet; A. Budziak; L. Bugge; T. Buran; A. Buys; J. A. M. A. Buytaert; M. Caccia; M. Calvi; A. J. Camacho Rozas; R. Campion; T. Bamporesi; V. Canale; K. Cankocak; F. Cao; F. Carena; P. Carrilho; L. Carroll; R. Cases; M. V. Castillo Gimenez; A. Cattai; F. R. Cavallo; L. Cerrito; V. Chabaud; A. Chan; M. Chapkin; Ph. Charpentier; J. Chauveau; P. Checchia; G. A. Chelkov; L. Chevalier; P. Chliapnikov; V. Chorowicz; J. T. M. Chrin; V. Cindro; P. Collins; J. L. Contreras; R. Contri; E. Cortina; G. Cosme; F. Couchot; H. B. Crawley; D. Crennell; G. Crosetti; J. Cuevas Maestro; S. Czellar; E. Dahl-Jensen; J. Dahm; B. Dalmagne; M. Dam; G. Damgaard; G. Darbo; E. Daubie; A. Daum; P. D. Dauncey; M. Davenport; J. Davies; J. Da Silva; C. Defoix; P. Delpierre; N. Demaria; A. De Angelis; H. De Boeck; W. De Boer; S. De Brabandere; C. De Clerq; M. D. M. De Fez Laso; C. De La Vaissiere; B. De Lotto; A. De Min; L. De Paula; H. Dijkstra; L. Di Ciaccio; F. Djama; J. Dolbeau; M. Donszelmann; K. Doroba; M. Dracos; J. Drees; M. Dris; Y. Dufour; F. Dupont; D. Edsall; L.-O. Eek; R. Ehret; T. Ekelof; G. Ekspong; A. Elliot Peisert; M. Elsing; J.-P. Engel; N. Ershaidat; M. Espirito Santo; D. Fassouliotis; M. Feindt; A. Fenyuk; A. Ferrer; T. A. Filippas; A. Firestone; H. Foeth; E. Fokitis; F. Fontanelli; K. A. J. Forbes; F. Formenti; J.-L. Fousset; S. Francon; B. Franek; P. Frenkiel; D. C. Fries; A. G. Frodesen; R. Fruhwirth; F. Fulda-Quenzer; H. Furstenau; J. Fuster; D. Gamba; M. Gandelman; C. Garcia; J. Garcia; C. Gaspar; U. Gasparini; Ph. Gavillet; E. N. Gazis; J.-P. Gerber; P. Giacomelli; D. Gillespie; R. Gokieli; B. Golob; V. M. Golovatyuk; J. J. Gomez Y Cadenas; G. Gopal; L. Gorn; M. Gorski; V. Gracco; F. Grard; E. Graziani; G. Grosdidier; B. Grossetete; P. Gunnarsson; J. Guy; U. Haedinger; F. Hahn; M. Hahn; S. Hahn; S. Haider; Z. Hajduk; A. Hakansson; A. Hallgren; U. Hamacher; G. Hamel De Monchenault; W. Hao; F. J. Harris; V. Hedberg; R. Henriques; J. J. Hernandez; J. A. Hernando; P. Herquet; H. Herr; T. L. Hessing; C. O. Higgins; E. Higon; H. J. Hilke; T. S. Hill; S. D. Hodgson; T. Hofmokl; S.-O. Holmgren; P. J. Holt; D. Holthuizen; P. F. Honore; M. Houlden; K. Huet; K. Hultqvist; P. Ioannou; P.-S. Iversen; J. N. Jackson; R. Jacobsson; P. Jalocha; G. Jarlskog; P. Jarry; B. Jean-Marie; E. K. Johansson; M. Jonker; L. Jonsson; P. Juillot; M. Kaiser; G. Kalkanis; G. Kalmus; F. Kapusta; M. Karlsson; E. Karvelas; S. Katsanevas; E. C. Katsoufis; R. Keranen; B. A. Khomenko; N. N. Khovanski; B. King; N. J. Kjaer; H. Klein; A. Klovning; P. Kluit; A. Koch-Mehrin; J. H. Koehne; B. Koene; P. Kokkinias; M. Koratzinos; K. Korcyl; A. V. Korytov; V. Kostioukhine; C. Kourkoumelis; O. Kouznetsov; P. H. Kramer; M. Krammer; C. Kreuter; J. Krolikowski; I. Kronkvist; W. Krupinski; W. Kucewicz; K. Kulka; K. Kurvinen; C. Lacasta; C. Lambropoulos; J. W. Lamsa; L. Lanceri; P. Langefeld; V. Lapin; I. Last; J.-P. Laugier; R. Lauhakangas; G. Leder; F. Ledroit; R. Leitner; Y. Lemoigne; J. Lemonne; G. Lenzen; V. Lepeltier; J. M. Levy; E. Lieb; D. Liko; J. Lindgren; R. Lindner; A. Lipniacka; I. Lippi; B. Loerstad; M. Lokajicek; J. G. Loken; A. Lopez-Fernandez; M. A. Lopez Aguera; M. Los; D. Loukas; J. J. Lozano; P. Lutz; L. Lyons; G. Maehlum; J. Maillard; A. Maio; A. Maltezos; F. Mandl; J. Marco; B. Marechal; M. Margoni; J.-C. Marin; C. Mariotti; A. Markou; T. Maron; S. Marti; C. Martinez-Rivero; F. Martinez-Vidal; F. Matorras; C. Matteuzzi; G. Matthiae; M. Mazzucato; M. McCubbin; R. McKay; R. McNulty; J. Medbo; C. Meroni; W. T. Meyer; M. Michelotto; E. Migliore; I. Mikulec; L. Mirabito; W. A. Mitaroff; G. V. Mitselmakher; U. Mjoernmark; T. Moa; R. Moeller; K. Moenig; M. R. Monge; P. Morettini; H. Mueller; W. J. Murray; B. Muryn; G. Myatt; F. Naraghi; F. L. Navarria; P. Negri; S. Nemecek; W. Neumann; N. Neumeister; R. Nicolaidou; B. S. Nielsen; V. Nikolaenko

1994-01-01

123

Pion-nucleon scattering and pion production in nucleon-nucleon and nucleus-nucleus collisions  

Microsoft Academic Search

Lecture notes are presented on the following: (1) basic aspects of ..pi..N interactions (properties of pions and nucleons, SU(3) and SU(6) classification phenomenology of ..pi..N scattering ((3.3) resonance; phase shift analysis, and bag model approach to ..pi..N); (2) pion production and absorption in the two nucleon system (NN ..-->.. NN..pi.. (isobar model) and ..pi..d reversible NN (existence of dibaryon resonances));

Dover

1982-01-01

124

Annato extract and ?-carotene modulate the production of reactive oxygen species/nitric oxide in neutrophils from diabetic rats.  

PubMed

Annatto has been identified as carotenoids that have antioxidative effects. It is well known that one of the key elements in the development of diabetic complications is oxidative stress. The immune system is especially vulnerable to oxidative damage because many immune cells, such as neutrophils, produce reactive oxygen species and reactive nitrogen species as part of the body's defense mechanisms to destroy invading pathogens. Reactive oxygen species/reactive nitrogen species are excessively produced by active peripheral neutrophils, and may damage essential cellular components, which in turn can cause vascular complications in diabetes. The present study was undertaken to evaluate the possible protective effects of annatto on the reactive oxygen species and nitric oxide (NO) inhibition in neutrophils from alloxan-induced diabetic rats. Adult female rats were divided into six groups based on receiving either a standard diet with or without supplementation of annatto extract or beta carotene. All animals were sacrificed 30 days after treatment and the neutrophils were isolated using two gradients of different densities. The reactive oxygen species and NO were quantified by a chemiluminescence and spectrophotometric assays, respectively. Our results show that neutrophils from diabetic animals produce significantly more reactive oxygen species and NO than their respective controls and that supplementation with beta carotene and annatto is able to modulate the production of these species. Annatto extract may have therapeutic potential for modulation of the balance reactive oxygen species/NO induced by diabetes. PMID:22573917

Rossoni-Júnior, Joamyr Victor; Araújo, Glaucy Rodrigues; Pádua, Bruno da Cruz; Chaves, Míriam Martins; Pedrosa, Maria Lúcia; Silva, Marcelo Eustáquio; Costa, Daniela Caldeira

2011-12-07

125

Annato extract and ?-carotene modulate the production of reactive oxygen species/nitric oxide in neutrophils from diabetic rats  

PubMed Central

Annatto has been identified as carotenoids that have antioxidative effects. It is well known that one of the key elements in the development of diabetic complications is oxidative stress. The immune system is especially vulnerable to oxidative damage because many immune cells, such as neutrophils, produce reactive oxygen species and reactive nitrogen species as part of the body’s defense mechanisms to destroy invading pathogens. Reactive oxygen species/reactive nitrogen species are excessively produced by active peripheral neutrophils, and may damage essential cellular components, which in turn can cause vascular complications in diabetes. The present study was undertaken to evaluate the possible protective effects of annatto on the reactive oxygen species and nitric oxide (NO) inhibition in neutrophils from alloxan-induced diabetic rats. Adult female rats were divided into six groups based on receiving either a standard diet with or without supplementation of annatto extract or beta carotene. All animals were sacrificed 30 days after treatment and the neutrophils were isolated using two gradients of different densities. The reactive oxygen species and NO were quantified by a chemiluminescence and spectrophotometric assays, respectively. Our results show that neutrophils from diabetic animals produce significantly more reactive oxygen species and NO than their respective controls and that supplementation with beta carotene and annatto is able to modulate the production of these species. Annatto extract may have therapeutic potential for modulation of the balance reactive oxygen species/NO induced by diabetes.

Rossoni-Junior, Joamyr Victor; Araujo, Glaucy Rodrigues; Padua, Bruno da Cruz; Chaves, Miriam Martins; Pedrosa, Maria Lucia; Silva, Marcelo Eustaquio; Costa, Daniela Caldeira

2012-01-01

126

High-resolution infrared spectroscopy: Jet-cooled halogenated methyl radicals and reactive scattering dynamics in an atom + polyatom system  

NASA Astrophysics Data System (ADS)

This thesis describes a series of projects whose common theme comprises the structure and internal energy distribution of gas-phase radicals. In the first two projects, shot noise-limited direct absorption spectroscopy is combined with long path-length slit supersonic discharges to obtain first high-resolution infrared spectra for jet-cooled CH2F and CH2Cl in the symmetric and antisymmetric CH2 stretching modes. Drawing motivation from the question of the equilibrium structures of halogen-substituted methyl radicals, spectral assignment yields refined lower and upper state rotational constants, as well as fine-structure parameters from least-square fits to the sub-Doppler lineshapes for individual transitions. High-level CCSD(T) calculations extrapolated to the complete basis set (CBS) limit confirm the existence of a non-planar (theta=29°) CH2F equilibrium structure with a 132 cm-1 barrier to planarity and a vibrational bend frequency of 276 cm-1. Similar calculations for CH 2Cl predict a slightly nonplanar equilibrium structure (theta=11°) with a vibrationally adiabatic one-dimensional treatment of the bend coordinate yielding a fundamental anharmonic frequency (393 cm-1). Both sets of calculations are in excellent agreement with previous studies. More interesting, however, are the unexpected intensity ratios of the symmetric vs. antisymmetric bands for CH2F and the absence of an antisymmetric band for CH2Cl. While a simple bond-dipole picture predicts a ratio of 1:3 for the symmetric vs. antisymmetric intensities, the experimentally observed value for CH2F is ˜2:1. This ratio is confirmed by DFT [B3LYP/aug-cc-pVTZ] calculations in a novel albeit indirect probe of the effective non-planarity for CH2F. For CH2Cl, similar DFT calculations predict a 30-fold decrease between the intensity of the symmetric and antisymmetric CH2 stretches, leading to the postulation of a nearly perfect cancellation of antisymmetric stretch intensity transition moment with chlorination. These two projects are followed by an investigation utilizing a well-characterized radical source, F, in a reaction with ethane to form HF and ethyl radical. The non-radical HF product is detected directly through similar high-resolution infrared absorption methods as described above, and its analysis is used to make inferences about the internal energy redistribution of the other radical fragment, ethyl. State-to-state reaction dynamics under single collision conditions are interpreted in the context of a simple impulsive model based on conservation of linear/angular momentum yields predictions in good agreement with experiment. Deviations from the model indicate only minor excitation of the ethyl vibrations, in contrast with a picture of extensive intramolecular vibrational energy flow but consistent with Franck-Condon excitation of the methylene CH2 bending mode. The results suggest a relatively simple dynamical picture for exothermic atom + polyatomic scattering, i.e., that of early barrier dynamics in atom + diatom systems but modified by impulsive recoil coupling at the transition state between translational/rotational degrees of freedom.

Whitney, Erin Sue

127

Reduced dimensionality diatom--diatom reactive scattering: Application to a model H sub 2 +A sub 2 r arrow H+HA sub 2 reaction  

SciTech Connect

We apply a recently formulated quantum theory of diatom--diatom reactions (Q. Sun and J. M. Bowman, Int. J. Quant. Chem., Quant. Chem. Symp. {bold 23}, 9 (1989)) to a model collinear H{sub 2}+A{sub 2}{r arrow}H+HA{sub 2} reaction, where A has the mass of a hydrogen atom. The theory assumes one diatom bond is nonreactive, and the reactive scattering Hamiltonian is written in terms of hyperspherical and cylindrical coordinates. The potential-energy surface used is the PK2 H+H{sub 2} surface augmented by a harmonic degree of freedom describing the nonreactive A{sub 2}. Details of the formulation and solution of the coupled-channel equations are given, along with convergence tests, and a discussion of the new state-to-state transition probabilities. In particular, the partial quenching of the well-known collinear H+H{sub 2} resonances is noted.

Sun, Q.; Bowman, J.M. (Department of Chemistry, Emory University, Atlanta, Georgia 30322 (US))

1990-01-15

128

Mitochondrial production of reactive oxygen species contributes to the ?-adrenergic stimulation of mouse cardiomycytes  

PubMed Central

Abstract The sympathetic adrenergic system plays a central role in stress signalling and stress is often associated with increased production of reactive oxygen species (ROS). Furthermore, the sympathetic adrenergic system is intimately involved in the regulation of cardiomyocyte Ca2+ handling and contractility. In this study we hypothesize that endogenously produced ROS contribute to the inotropic mechanism of ?-adrenergic stimulation in mouse cardiomyocytes. Cytoplasmic Ca2+ transients, cell shortening and ROS production were measured in freshly isolated cardiomyocytes using confocal microscopy and fluorescent indicators. As a marker of oxidative stress, malondialdehyde (MDA) modification of proteins was detected with Western blotting. Isoproterenol (ISO), a ?-adrenergic agonist, increased mitochondrial ROS production in cardiomyocytes in a concentration- and cAMP–protein kinase A-dependent but Ca2+-independent manner. Hearts perfused with ISO showed a twofold increase in MDA protein adducts relative to control. ISO increased Ca2+ transient amplitude, contraction and L-type Ca2+ current densities (measured with whole-cell patch-clamp) in cardiomyocytes and these increases were diminished by application of the general antioxidant N-acetylcysteine (NAC) or the mitochondria-targeted antioxidant SS31. In conclusion, increased mitochondrial ROS production plays an integral role in the acute inotropic response of cardiomyocytes to ?-adrenergic stimulation. On the other hand, chronically sustained adrenergic stress is associated with the development of heart failure and cardiac arrhythmias and prolonged increases in ROS may contribute to these defects.

Andersson, Daniel C; Fauconnier, Jeremy; Yamada, Takashi; Lacampagne, Alain; Zhang, Shi-Jin; Katz, Abram; Westerblad, Hakan

2011-01-01

129

The effect of electromagnetic field on reactive oxygen species production in human neutrophils in vitro.  

PubMed

The present study was undertaken in order to determine the effect of low frequency electromagnetic field (EMF) on reactive oxygen species (ROS) production in human neutrophils in peripheral blood in vitro. We investigated how differently generated EMF and several levels of magnetic induction affect ROS production. To evaluate the level of ROS production, two fluorescent dyes were used: 2'7'-dichlorofluorscein-diacetate and dihydrorhodamine. Phorbol 12-myristate 13-acetate (PMA), known as strong stimulator of the respiratory burst, was also used. Alternating magnetic field was generated by means of Viofor JPS apparatus. Three different levels of magnetic induction have been analyzed (10, 40 and 60 ?T). Fluorescence of dichlorofluorescein and 123 rhodamine was measured by flow cytometry. The experiments demonstrated that only EMF tuned to the calcium ion cyclotron resonance frequency was able to affect ROS production in neutrophils. Statistical analysis showed that this effect depended on magnetic induction value of applied EMF. Incubation in EMF inhibited cell activity slightly in unstimulated neutrophils, whereas the activity of PMA-stimulated neutrophils has increased after incubation in EMF. PMID:23137127

Poniedzialek, Barbara; Rzymski, Piotr; Nawrocka-Bogusz, Honorata; Jaroszyk, Feliks; Wiktorowicz, Krzysztof

2012-11-08

130

First measurement of Z/?* production in compton scattering of quasi-real photons  

NASA Astrophysics Data System (ADS)

We report the first observation of Z/?* production in Compton scattering of quasi-real photons. This is a subprocess of the reaction e+e--->e+e- Z/?*, where one of the final state electrons is undetected. Approximately 55 pb-1 of data collected in the year 1997 at an e+e- centre-of-mass energy of 183 GeV with the OPAL detector at LEP have been analysed. The Z/?* from Compton scattering has been detected in the hadronic decay channel. Within well defined kinematic bounds, we measure the product of cross-section and Z/?* branching ratio to hadrons to be (0.9+/-0.3+/-0.1) pb for events with a hadronic mass larger than 60 GeV, dominated by (e)eZ production. In the hadronic mass region between 5 GeV and 60 GeV, dominated by (e)e?* production, this product is found to be (4.1+/-1.6+/-0.6) pb. Our results agree with the predictions of two Monte Carlo event generators, grc4f and PYTHIA.

OPAL Collaboration; Abbiendi, G.; Ackerstaff, K.; Alexander, G.; Allison, J.; Altekamp, N.; Anderson, K. J.; Anderson, S.; Arcelli, S.; Asai, S.; Ashby, S. F.; Axen, D.; Azuelos, G.; Ball, A. H.; Barberio, E.; Barlow, R. J.; Bartoldus, R.; Batley, J. R.; Baumann, S.; Bechtluft, J.; Behnke, T.; Bell, K. W.; Bella, G.; Bellerive, A.; Bentvelsen, S.; Bethke, S.; Betts, S.; Biebel, O.; Biguzzi, A.; Bird, S. D.; Blobel, V.; Bloodworth, I. J.; Bobinski, M.; Bock, P.; Böhme, J.; Bonacorsi, D.; Boutemeur, M.; Braibant, S.; Bright-Thomas, P.; Brigliadori, L.; Brown, R. M.; Burckhart, H. J.; Burgard, C.; Bürgin, R.; Capiluppi, P.; Carnegie, R. K.; Carter, A. A.; Carter, J. R.; Chang, C. Y.; Charlton, D. G.; Chrisman, D.; Ciocca, C.; Clarke, P. E. L.; Clay, E.; Cohen, I.; Conboy, J. E.; Cooke, O. C.; Couyoumtzelis, C.; Coxe, R. L.; Cuffiani, M.; Dado, S.; Dallavalle, G. M.; Davis, R.; de Jong, S.; del Pozo, L. A.; de Roeck, A.; Desch, K.; Dienes, B.; Dixit, M. S.; Dubbert, J.; Duchovni, E.; Duckeck, G.; Duerdoth, I. P.; Eatough, D.; Estabrooks, P. G.; Etzion, E.; Evans, H. G.; Fabbri, F.; Fanti, M.; Faust, A. A.; Fiedler, F.; Fierro, M.; Fleck, I.; Folman, R.; Fürtjes, A.; Futyan, D. I.; Gagnon, P.; Gary, J. W.; Gascon, J.; Gascon-Shotkin, S. M.; Gaycken, G.; Geich-Gimbel, C.; Giacomelli, G.; Giacomelli, P.; Gibson, V.; Gibson, W. R.; Gingrich, D. M.; Glenzinski, D.; Goldberg, J.; Gorn, W.; Grandi, C.; Gross, E.; Grunhaus, J.; Gruwé, M.; Hanson, G. G.; Hansroul, M.; Hapke, M.; Harder, K.; Hargrove, C. K.; Hartmann, C.; Hauschild, M.; Hawkes, C. M.; Hawkings, R.; Hemingway, R. J.; Herndon, M.; Herten, G.; Heuer, R. D.; Hildreth, M. D.; Hill, J. C.; Hillier, S. J.; Hobson, P. R.; Hocker, A.; Homer, R. J.; Honma, A. K.; Horváth, D.; Hossain, K. R.; Howard, R.; Hüntemeyer, P.; Igo-Kemenes, P.; Imrie, D. C.; Ishii, K.; Jacob, F. R.; Jawahery, A.; Jeremie, H.; Jimack, M.; Jones, C. R.; Jovanovic, P.; Junk, T. R.; Karlen, D.; Kartvelishvili, V.; Kawagoe, K.; Kawamoto, T.; Kayal, P. I.; Keeler, R. K.; Kellogg, R. G.; Kennedy, B. W.; Klier, A.; Kluth, S.; Kobayashi, T.; Kobel, M.; Koetke, D. S.; Kokott, T. P.; Kolrep, M.; Komamiya, S.; Kowalewski, R. V.; Kress, T.; Krieger, P.; von Krogh, J.; Kuhl, T.; Kyberd, P.; Lafferty, G. D.; Lanske, D.; Lauber, J.; Lautenschlager, S. R.; Lawson, I.; Layter, J. G.; Lazic, D.; Lee, A. M.; Lellouch, D.; Letts, J.; Levinson, L.; Liebisch, R.; List, B.; Littlewood, C.; Lloyd, A. W.; Lloyd, S. L.; Loebinger, F. K.; Long, G. D.; Losty, M. J.; Ludwig, J.; Liu, D.; Macchiolo, A.; MacPherson, A.; Mader, W.; Mannelli, M.; Marcellini, S.; Markopoulos, C.; Martin, A. J.; Martin, J. P.; Martinez, G.; Mashimo, T.; Mättig, P.; McDonald, W. J.; McKenna, J.; McKigney, E. A.; McMahon, T. J.; McPherson, R. A.; Meijers, F.; Menke, S.; Merritt, F. S.; Mes, H.; Meyer, J.; Michelini, A.; Mihara, S.; Mikenberg, G.; Miller, D. J.; Mir, R.; Mohr, W.; Montanari, A.; Mori, T.; Nagai, K.; Nakamura, I.; Neal, H. A.; Nellen, B.; Nisius, R.; O'Neale, S. W.; Oakham, F. G.; Odorici, F.; Ogren, H. O.; Oreglia, M. J.; Orito, S.; Pálinkás, J.; Pásztor, G.; Pater, J. R.; Patrick, G. N.; Patt, J.; Perez-Ochoa, R.; Petzold, S.; Pfeifenschneider, P.; Pilcher, J. E.; Pinfold, J.; Plane, D. E.; Poffenberger, P.; Polok, J.; Przybycie? , M.; Rembser, C.; Rick, H.; Robertson, S.; Robins, S. A.; Rodning, N.; Roney, J. M.; Roscoe, K.; Rossi, A. M.; Rozen, Y.; Runge, K.; Runolfsson, O.; Rust, D. R.; Sachs, K.; Saeki, T.; Sahr, O.; Sang, W. M.; Sarkisyan, E. K. G.; Sbarra, C.; Schaile, A. D.; Schaile, O.; Scharf, F.; Scharff-Hansen, P.; Schieck, J.; Schmitt, B.; Schmitt, S.; Schöning, A.; Schröder, M.; Schumacher, M.; Schwick, C.; Scott, W. G.; Seiler, T.; Seuster, R.; Shears, T. G.; Shen, B. C.; Shepherd-Themistocleous, C. H.; Sherwood, P.; Siroli, G. P.; Sittler, A.; Skuja, A.; Smith, A. M.; Snow, G. A.; Sobie, R.; Söldner-Rembold, S.; Sproston, M.; Stahl, A.; Stephens, K.; Steuerer, J.; Stoll, K.; Strom, D.; Ströhmer, R.; Surrow, B.; Talbot, S. D.; Tanaka, S.; Taras, P.; Tarem, S.; Teuscher, R.; Thiergen, M.; Thomson, M. A.; von Törne, E.; Torrence, E.; Towers, S.; Trigger, I.; Trócsányi, Z.; Tsur, E.; Turcot, A. S.; Turner-Watson, M. F.; van Kooten, R.; Vannerem, P.; Verzocchi, M.; Voss, H.; Wäckerle, F.; Wagner, A.; Ward, C. P.; Ward, D. R.; Watkins, P. M.; Watson, A. T.; Watson, N. K.; Wells, P. S.; Wermes, N.; White, J. S.; Wilson, G. W.; Wilson, J. A.; Wyatt, T. R.; Yamashita, S.; Yekutieli, G.; Zacek, V.; Zer-Zion, D.

1998-10-01

131

Terrestrial P and Reactive N and Marine Productivity in the Late Devonian Appalachian Basin  

NASA Astrophysics Data System (ADS)

A causal link between the Late Devonian emergence of forest ecosystems and episodic black shale deposition has been proposed by several authors. Most attribute increases in epicontinental basin productivity to elevated rates of terrestrial phosphorus weathering facilitated by the co-evolution of root systems and soils. Two reasons to suspect that an increase in the P weathering flux was not the primary cause of organic-rich shale deposition are as follows. First, most Late Devonian black shales were deposited during sea level transgressions, periods when riverine fluxes of sediment and mineral nutrients such as P to marine basins were diminished. Second, Late Devonian forests were restricted to warm, moist lowlands where P was sequestered in soils as inorganic, occluded forms. However, the export flux of reactive N from these forests to adjacent epeiric seas by riverine and atmospheric deposition was enhanced by the warm, wet climate and expanding areal extent of forests. Abundant terrestrial reactive N primed the marine eutrophication pump by extending the residence time of P in the photic zone, permitting extensive growth of primary biomass. The consequent flux of organic matter to the sea floor created anoxic bottom waters that, in turn, allowed for the remobilization of P into the water column. Based on abundance and isotopic analyses of organic and inorganic C, N, P, and S from terrestrial and marine environments within and adjacent to the Late Devonian Appalachian Basin, this latter scenario is supported.

Tuite, M. L.; Macko, S. A.

2009-12-01

132

Product and Mechanistic Analysis of the Reactivity of a C6-Pyrimidine Radical in RNA  

PubMed Central

Nucleobase radicals are the major reactive intermediates produced when hydroxyl radical reacts with nucleic acids. 5,6-Dihydrouridin-6-yl radical (1) was independently generated from a ketone precursor via Norrish Type I photocleavage in a dinucleotide, single stranded, and double stranded RNA. This radical is a model of the major hydroxyl radical adduct of uridine. Tandem lesions resulting from addition of the peroxyl radical derived from 1 to the 5?-adjacent nucleotide are observed by ESI- MS. Radical 1 produces direct strand breaks at the 5?-adjacent nucleotide and at the initial site of generation. The preference for cleavage at these two positions depends upon the secondary structure of the RNA and whether O2 is present or not. Varying the identity of the 5?-adjacent nucleotide has little effect on strand scission. In general, strand scission is significantly more efficient under anaerobic conditions than when O2 is present. Strand scission is more than twice as efficient in double stranded RNA than in a single stranded oligonucleotide under anaerobic conditions. Internucleotidyl strand scission occurs via ?-fragmentation following C2?-hydrogen atom abstraction by 1. The subsequently formed olefin cation radical ultimately yields products containing 3?-phosphate or 3?-deoxy-2?-ketouridine termini. These end groups are proposed to result from competing deprotonation pathways. The dependence of strand scission efficiency from 1 on secondary structure under anaerobic conditions suggests that this reactivity may be useful for extracting additional RNA structural information from hydroxyl radical reactions.

Jacobs, Aaron C.; Resendiz, Marino J. E.; Greenberg, Marc M.

2011-01-01

133

Interactions of U.S. Agricultural Production with Climatic Stresses and Reactive Nitrogen  

NASA Astrophysics Data System (ADS)

Agricultural production both contributes to and responds to climatic variations across spatial and temporal continuums. The agriculture sector is responsible for over 6% of total U.S. greenhouse gas emissions, primarily as methane (CH4) and nitrous oxide (N2O) gases emitted by agricultural activities. Agriculture activities specifically account for about 69% of U.S. N2O emissions, largely as a result of production practices including fertilizer management, cropping systems, and manure management. Fertilizers, together with manure and legume fixation, are the three main inputs of N to US agricultural soils. All three sources have been increasing over the past two decades, while the rate at which they are removed in the form of harvested crops has been increasing at a slightly slower rate. The outlook for continued large areas of cultivation in the U.S., specifically for corn production and supported by biofuel production goals, is a major factor in sustaining demand for N fertilizer. However, rising fertilizer prices and environmental pressures on producers are encouraging increased adoption of emerging technologies such as precision agriculture, cultivars with higher N use efficiency, and enhanced-efficiency N sources such as controlled-release forms or forms with urease or nitrification inhibitors. Crop productivity also responds to climatic changes, as crop growth is affected by variables including heat, drought, ozone (O3), and increased ambient carbon dioxide (CO2). We summarize sources and fates of N for cropping systems and intensive animal systems and assess how climate change will affect crop response to and recovery of N and subsequent cascading effects on Nr. The complex interactions between agricultural Nr and climate present opportunities for mitigation/adaption relative to N use. N fertilizer and manure management, tillage, technology, and decision support models provide significant opportunities for climate mitigation and adaption in U.S. agriculture. Here we summarize reactive nitrogen (Nr)-climate interactions as they relate to U.S. agricultural production.

Gehl, R. J.; Robertson, G. P.; Bruulsema, T. W.; Kanter, D.; Mauzerall, D. L.; Rotz, C. A.; Williams, C. O.

2011-12-01

134

Free sphingobases induce RBOHD-dependent reactive oxygen species production in Arabidopsis leaves.  

PubMed

Sphingolipids are implied in several regulatory processes, including cell death. Levels of the free sphingobase t18:0 (phytosphingosine) increase in Arabidopsis in response to the bacterial pathogen Pseudomonas syringae. To gain information on sphingobase-induced signaling, we determined kinetics of leaf reactive oxygen species (ROS) levels and cell death in response to specific sphingobases. t18:0, d18:0 and d17:1, but not d20:0, induced ROS and cell death within 1.5-2h. Early sphingobase-induced ROS production was independent of cell death induction and required the NADPH oxidase Respiratory Burst Oxidase Homolog D (RBOHD). Specific sphingobases can therefore induce cell death and require RBOHD for early ROS induction in plants. PMID:21856300

Peer, Markus; Bach, Matthias; Mueller, Martin J; Waller, Frank

2011-08-16

135

D^* production in deep-inelastic scattering at low Q^2  

SciTech Connect

Inclusive production of D* mesons in deep-inelastic scattering at HERA is studied in the range 5 < Q{sup 2} < 100 GeV{sup 2} of the photon virtuality and 0.02 < y < 0.70 of the inelasticity of the scattering process. The visible range for the D* meson is p{sub T} (D*) > 1.25 GeV and |{eta}(D*)| < 1.8. The data were taken with the H1 detector in the years 2004 to 2007 and correspond to an integrated luminosity of 347 pb{sup -1}. Single and double differential cross sections are measured. The results are compared to QCD predictions.

Jung, Andreas W.; /Fermilab

2011-07-01

136

Measurement of D meson production in ep scattering at low Q  

NASA Astrophysics Data System (ADS)

The production of D(2010) mesons in ep scattering in the range of exchanged photon virtuality 0.05scattered electron. Differential D cross sections as functions of Q, inelasticity, y, transverse momentum of the D meson, p(D), and pseudorapidity of the D meson, ?(D), have been measured in the kinematic region 0.02

Chekanov, S.; ZEUS Collaboration; Derrick, M.; Magill, S.; Miglioranzi, S.; Musgrave, B.; Nicholass, D.; Repond, J.; Yoshida, R.; Mattingly, M. C. K.; Jechow, M.; Pavel, N.; Yagües Molina, A. G.; Antonelli, S.; Antonioli, P.; Bari, G.; Basile, M.; Bellagamba, L.; Bindi, M.; Boscherini, D.; Bruni, A.; Bruni, G.; Cifarelli, L.; Cindolo, F.; Contin, A.; Corradi, M.; de Pasquale, S.; Iacobucci, G.; Margotti, A.; Nania, R.; Polini, A.; Rinaldi, L.; Sartorelli, G.; Zichichi, A.; Bartsch, D.; Brock, I.; Goers, S.; Hartmann, H.; Hilger, E.; Irrgang, P.; Jakob, H.-P.; Jüngst, M.; Kind, O. M.; Paul, E.; Renner, R.; Samson, U.; Schönberg, V.; Shehzadi, R.; Wlasenko, M.; Brook, N. H.; Heath, G. P.; Morris, J. D.; Namsoo, T.; Capua, M.; Fazio, S.; Mastroberardino, A.; Schioppa, M.; Susinno, G.; Tassi, E.; Kim, J. Y.; Ma, K. J.; Ibrahim, Z. A.; Kamaluddin, B.; Wan Abdullah, W. A. T.; Ning, Y.; Ren, Z.; Sciulli, F.; Chwastowski, J.; Eskreys, A.; Figiel, J.; Galas, A.; Gil, M.; Olkiewicz, K.; Stopa, P.; Zawiejski, L.; Adamczyk, L.; Bo?d, T.; Grabowska-Bo?d, I.; Kisielewska, D.; ?ukasik, J.; Przybycie?, M.; Suszycki, L.; Kota?ski, A.; S?omi?ski, W.; Adler, V.; Behrens, U.; Bloch, I.; Blohm, C.; Bonato, A.; Borras, K.; Coppola, N.; Dossanov, A.; Fourletova, J.; Geiser, A.; Gladkov, D.; Göttlicher, P.; Gregor, I.; Haas, T.; Hain, W.; Horn, C.; Kahle, B.; Klein, U.; Kötz, U.; Kowalski, H.; Lobodzinska, E.; Löhr, B.; Mankel, R.; Melzer-Pellmann, I.-A.; Montanari, A.; Notz, D.; Nuncio-Quiroz, A. E.; Rubinsky, I.; Santamarta, R.; Schneekloth, U.; Spiridonov, A.; Stadie, H.; Szuba, D.; Szuba, J.; Theedt, T.; Wolf, G.; Wrona, K.; Youngman, C.; Zeuner, W.; Lohmann, W.; Schlenstedt, S.; Barbagli, G.; Gallo, E.; Pelfer, P. G.; Bamberger, A.; Dobur, D.; Karstens, F.; Vlasov, N. N.; Bussey, P. J.; Doyle, A. T.; Dunne, W.; Ferrando, J.; Saxon, D. H.; Skillicorn, I. O.; Gialas, I.; Gosau, T.; Holm, U.; Klanner, R.; Lohrmann, E.; Salehi, H.; Schleper, P.; Schörner-Sadenius, T.; Sztuk, J.; Wichmann, K.; Wick, K.; Foudas, C.; Fry, C.; Long, K. R.; Tapper, A. D.; Kataoka, M.; Matsumoto, T.; Nagano, K.; Tokushuku, K.; Yamada, S.; Yamazaki, Y.; Barakbaev, A. N.; Boos, E. G.; Pokrovskiy, N. S.; Zhautykov, B. O.; Son, D.; de Favereau, J.; Piotrzkowski, K.; Barreiro, F.; Glasman, C.; Jimenez, M.; Labarga, L.; Del Peso, J.; Ron, E.; Soares, M.; Terrón, J.; Zambrana, M.; Corriveau, F.; Liu, C.; Walsh, R.; Zhou, C.; Tsurugai, T.; Antonov, A.; Dolgoshein, B. A.; Sosnovtsev, V.; Stifutkin, A.; Suchkov, S.; Dementiev, R. K.; Ermolov, P. F.; Gladilin, L. K.; Katkov, I. I.; Khein, L. A.; Korzhavina, I. A.; Kuzmin, V. A.; Levchenko, B. B.; Lukina, O. Yu.; Proskuryakov, A. S.; Shcheglova, L. M.; Zotkin, D. S.; Zotkin, S. A.; Abt, I.; Büttner, C.; Caldwell, A.; Kollar, D.; Schmidke, W. B.; Sutiak, J.; Grigorescu, G.; Keramidas, A.; Koffeman, E.; Kooijman, P.; Pellegrino, A.; Tiecke, H.; Vázquez, M.; Wiggers, L.; Brümmer, N.; Bylsma, B.; Durkin, L. S.; Lee, A.; Ling, T. Y.; Allfrey, P. D.; Bell, M. A.; Cooper-Sarkar, A. M.; Cottrell, A.; Devenish, R. C. E.; Foster, B.; Korcsak-Gorzo, K.; Patel, S.; Roberfroid, V.; Robertson, A.; Straub, P. B.; Uribe-Estrada, C.; Walczak, R.; Bellan, P.; Bertolin, A.; Brugnera, R.; Carlin, R.; Ciesielski, R.; Dal Corso, F.; Dusini, S.; Garfagnini, A.; Limentani, S.; Longhin, A.; Stanco, L.; Turcato, M.; Oh, B. Y.; Raval, A.; Ukleja, J.; Whitmore, J. J.; Iga, Y.; D'Agostini, G.; Marini, G.; Nigro, A.; Cole, J. E.; Hart, J. C.; Abramowicz, H.; Gabareen, A.; Ingbir, R.; Kananov, S.; Levy, A.; Kuze, M.; Hori, R.; Kagawa, S.; Okazaki, N.; Shimizu, S.; Tawara, T.; Hamatsu, R.; Kaji, H.; Kitamura, S.; Ota, O.; Ri, Y. D.; Ferrero, M. I.; Monaco, V.; Sacchi, R.; Solano, A.; Arneodo, M.; Ruspa, M.; Fourletov, S.; Martin, J. F.; Boutle, S. K.; Butterworth, J. M.; Gwenlan, C.; Hall-Wilton, R.; Jones, T. W.; Loizides, J. H.; Sutton, M. R.; Targett-Adams, C.; Wing, M.; Brzozowska, B.; Ciborowski, J.; Grzelak, G.; Kulinski, P.; ?u?niak, P.; Malka, J.; Nowak, R. J.; Pawlak, J. M.; Tymieniecka, T.; Ukleja, A.; ?arnecki, A. F.; Adamus, M.; Plucinski, P.; Eisenberg, Y.; Giller, I.; Hochman, D.; Karshon, U.; Rosin, M.; Brownson, E.; Danielson, T.; Everett, A.; Kçira, D.; Reeder, D. D.; Ryan, P.; Savin, A. A.; Smith, W. H.; Wolfe, H.; Bhadra, S.; Catterall, C. D.; Cui, Y.; Hartner, G.; Menary, S.; Noor, U.; Standage, J.; Whyte, J.

2007-05-01

137

Kinetics and Product Yields in the Heterogeneous Reactions of HOBr with Reactive Halide Surfaces  

NASA Astrophysics Data System (ADS)

Routine episodes of ozone destruction in the springtime Arctic boundary layer have been well documented in recent years. After polar sunrise, field researchers working in Alaska and northern Canada report the almost complete loss of ozone from stable air masses in coastal regions. Ozone destruction is very fast, developing on a time scale from hours to days. Low ozone levels are correlated with elevated filterable bromine concentrations, suggesting that high levels of active bromine compounds are present in the atmosphere during ozone loss events. Based on these and other observations, a number of heterogeneous mechanisms involving bromine radicals have been proposed to explain the ozone-depleting chemistry. The central reactions in many of these theories are the interactions of gaseous HOBr with sea salt components in marine aerosols, snow crystals, or sea ice. Recent modeling studies suggest that tropospheric ozone destruction can not be simulated in agreement with field observations unless heterogeneous reactions with HOBr are included. The interactions of HOBr with sea salt halides also drive a proposed autocatalytic mechanism that explains many aspects of the rapid and nearly wholesale loss of ozone in the Arctic troposphere. Motivated by the central role of HOBr in these modeling studies, we have investigated its heterogeneous reactions with reactive halide-ice surfaces using a coated wall, low-pressure flow tube coupled to a quadrupole mass spectrometer. Gas-surface reaction probabilities and product yields are presented for two different temperatures and a range of halide and hydrogen ion concentrations in ice. Compared to results for similar experiments with HOCl that have been conducted previously, HOBr reaction probability values are smaller than expected, but still significant. The relative yields of gas-phase products Br2 and BrCl depend on the temperature, composition, and acidity of the reactive halide-ice surfaces. Overall, our data suggest that the heterogeneous reactions of HOBr on sea ice and snow crystals may be a significant source of active bromine in the Arctic boundary layer.

Huff, A. K.; Huff, A. K.; Abbatt, J. P.

2001-12-01

138

Reactive Oxygen Species Production in Energized Cardiac Mitochondria During Hypoxia/Reoxygenation: Modulation by Nitric Oxide  

PubMed Central

Mitochondria are an important source of reactive oxygen species (ROS) implicated in ischemia/reperfusion injury. When isolated from ischemic myocardium, mitochondria demonstrate increased ROS production as a result of damage to electron transport complexes. To investigate the mechanisms, we studied effects of hypoxia/reoxygenation on ROS production by isolated energized heart mitochondria. ROS production, tracked using Fe2+-catalyzed, H2O2-dependent H2DCF oxidation or Amplex Red, was similar during normoxia and hypoxia, but markedly increased during reoxygenation, in proportion to the duration of hypoxia. In contrast, if mitochondria were rapidly converted from normoxia to near-anoxia ([O2]< 1 ?M), the increase in H2DCF oxidation rate during reoxygenation was markedly blunted. To elicit the robust increase in H2DCF oxidation rate during reoxygenation, hypoxia had to be severe enough to cause partial, but not complete, respiratory chain inhibition (as shown by partial dissipation of membrane potential and increased NADH auto-fluorescence). Consistent with its cardioprotective actions, nitric oxide (•NO) abrogated increased H2DCF oxidation under these conditions, as well as attenuating ROS-induced increases in matrix [Fe2+] and aconitase inhibition caused by antimycin. Collectively, these results suggest that a) hypoxia sufficient to cause partial respiratory inhibition is more damaging to mitochondria than near-anoxia; b) •NO suppresses ROS-induced damage to electron transport complexes, probably by forming •NO-Fe2+ complexes in the presence of glutathione which inhibit hydroxyl radical formation.

Korge, Paavo; Ping, Peipei; Weiss, James N

2009-01-01

139

Production of reactive oxygen species in response to replication stress and inappropriate mitosis in fission yeast  

PubMed Central

Summary Previous studies have indicated that replication stress can trigger apoptosis-like cell death, accompanied (where tested) by production of reactive oxygen species (ROS), in mammalian cells and budding yeast (Saccharomyces cerevisiae). In mammalian cells, inappropriate entry into mitosis also leads to cell death. Here we report similar responses in fission yeast (Schizosaccharomyces pombe). We used ROS- and death-specific fluorescent stains to measure the effects of mutations in replication initiation and checkpoint genes in fission yeast on the frequencies of ROS production and cell death. We found that certain mutant alleles of each of the four tested replication initiation genes caused elevated ROS and cell death. Where tested, these effects were not enhanced by checkpoint gene mutations. Instead, when cells that were competent for replication but defective in both the replication and damage checkpoints were treated with hydroxyurea, which slows replication fork movement, the frequencies of ROS production and cell death were greatly increased. This was a consequence of elevated CDK activity, which permitted inappropriate entry into mitosis. Thus studies in fission yeast are likely to prove helpful in understanding the pathways that lead both from replication stress and from inappropriate mitosis to cell death in mammalian cells.

Marchetti, Maria A; Weinberger, Martin; Murakami, Yota; Burhans, William C; Huberman, Joel A

2006-01-01

140

Simultaneous production of laccase and decolouration of the diazo dye Reactive Black 5 in a fixed-bed bioreactor  

Microsoft Academic Search

In this paper the production of laccase and the decolouration of the recalcitrant diazo dye Reactive Black 5 (RB5) by the white-rot fungus Trametes pubescens immobilised on stainless steel sponges in a fixed-bed reactor were studied. Laccase production was increased by 10-fold in the presence of RB5 and reached a maximum value of 1025U\\/l. Enhanced laccase production in the presence

Kheirghadam Enayatzamir; Hossein A. Alikhani; Susana Rodríguez Couto

2009-01-01

141

Reactive scattering dynamics of rotational wavepackets: A case study using the model H+H2 and F+H2 reactions with aligned and anti-aligned H2.  

PubMed

We propose a method to steer the outcome of reactive atom-diatom scattering, using rotational wavepackets excited by strong non-resonant laser pulses. Full close-coupled quantum mechanical scattering calculations of the D+H2 and F+H2 reactions are presented, where the H2 molecule exists as a coherent superposition of rotational states. The nuclear spin selective control over the molecular bond axis alignment afforded by the creation of rotational wavepackets is applied to reactive scattering systems, enabling a nuclear spin selective influence to be exerted over the reactive dynamics. The extension of the conventional eigenstate-to-eigenstate scattering problem to the case in which the initial state is composed of a coherent superposition of rotational states is detailed, and a selection of example calculations are discussed, along with their mechanistic implications. The feasibility of the corresponding experiments is considered, and a suitable simple two pulse laser scheme is shown to strongly differentiate the reactivities of o-H2 and p-H2. PMID:24050352

Eyles, C J; Leibscher, M

2013-09-14

142

Reactive scattering dynamics of rotational wavepackets: A case study using the model H+H2 and F+H2 reactions with aligned and anti-aligned H2  

NASA Astrophysics Data System (ADS)

We propose a method to steer the outcome of reactive atom-diatom scattering, using rotational wavepackets excited by strong non-resonant laser pulses. Full close-coupled quantum mechanical scattering calculations of the D+H2 and F+H2 reactions are presented, where the H2 molecule exists as a coherent superposition of rotational states. The nuclear spin selective control over the molecular bond axis alignment afforded by the creation of rotational wavepackets is applied to reactive scattering systems, enabling a nuclear spin selective influence to be exerted over the reactive dynamics. The extension of the conventional eigenstate-to-eigenstate scattering problem to the case in which the initial state is composed of a coherent superposition of rotational states is detailed, and a selection of example calculations are discussed, along with their mechanistic implications. The feasibility of the corresponding experiments is considered, and a suitable simple two pulse laser scheme is shown to strongly differentiate the reactivities of o-H2 and p-H2.

Eyles, C. J.; Leibscher, M.

2013-09-01

143

Production of reactive oxygen species by man-made vitreous fibres in human polymorphonuclear leukocytes.  

PubMed

Human polymorphonuclear leukocytes (PMNL) or erythrocytes, isolated from human blood, were exposed to graded doses of asbestos (chrysotile), quartz, or man-made vitreous fibres (MMVF), i.e. refractory ceramic fibres (RCF), glasswool, or rockwool fibres. None of the MMVF affected either the viability of PMNL, as measured by trypan blue exclusion test, or induced haemolysis, whereas the positive controls, quartz and chrysotile, dose-dependently induced haemolysis in PMNL. MMVF did not increase the release of lactate dehydrogenase (LDH) from the PMNL, whereas the positive controls, chrysotile and quartz, induced a marked and dose-dependent release of LDH. When PMNL were exposed to MMVF, some of the fibre types slightly increased the levels of free intracellular calcium ([Ca2+]i) within the cells in a manner similar to that induced by chrysotile or quartz. All MMVF induced a dose-dependent production of reactive oxygen species (ROS) in PMNL, with RCF-induced production of ROS being the most marked. Production of ROS by MMVF seemed to depend on the availability of extracellular calcium because it could be attenuated with a Ca2+ channel blocker, verapamil, or a Ca2+ chelating agent, EGTA. Production of ROS may be a common pathway through which PMNL respond to MMVF-induced cell activation, but alterations of levels of free intracellular Ca2+ do not seem to be an absolute prerequisite for this effect. Fibre length seemed not to be an important factor in affecting the ability of MMVF to induce ROS production in PMNL. However, the balance between different elements in the fibre seemed importantly to affect the biological activity of a fibre. PMID:10413242

Ruotsalainen, M; Hirvonen, M R; Luoto, K; Savolainen, K M

1999-06-01

144

The ozone productivity of n-propyl bromide: Part 2--An exception to the Maximum Incremental Reactivity Scale.  

PubMed

In an earlier paper the ozone-forming potential of n-propyl bromide (NPB) was studied with a new methodology designed to address issues associated with a marginal smog-forming compound. However, the U.S. Environmental Protection Agency (EPA) subsequently revised its policy and now recommends using the Maximum Incremental Reactivity (MIR) scale to rank the ozone-forming potential of all volatile organic compounds (VOCs), including those of marginal ozone productivity. Nevertheless, EPA contemplated exceptions to the box-model-derived MIR scale by allowing use of photochemical grid-model simulations for case specific reactivity assessments. The California Air Resources Board (CARB) also uses the MIR scale and CARB has a Reactivity Scientific Advisory Committee that can consider exceptions to the MIR scale. In this study, grid-model simulations that were recommended by EPA are used to evaluate the incremental ozone impacts of NPB using an update to the chemical mechanism developed in an earlier paper. New methods of analysis of the grid-model output are further developed here to quantify the relative reactivities between NPB and ethane over a wide range of conditions. The new grid-model-based analyses show that NPB is significantly different and generally less in ozone-forming potential (i.e., reactivity) than predicted by the box-model-based MIR scale relative to ethane, EPA's "bright-line" test for non-VOC status. Although NPB has low reactivity compared to typical VOCs on any scale, the new grid-model analyses developed here show that NPB is far less reactive (and even has negative reactivity) compared to the reactivity predicted by the MIR scale. PMID:18672713

Whitten, Gary Z; Yarwood, Greg

2008-07-01

145

Reactive ion etching profile and depth characterization using statistical and neural network analysis of light scattering data  

NASA Astrophysics Data System (ADS)

Scatterometry was applied to inspect reactively ion etched structures in single-crystalline Si. The resultant scattergrams were studied using both discriminant analysis and neural networks. In both instances, after the algorithms are trained, they can be utilized to classify 'unknown' wafers and signal departures from a nominal, target value. Discriminant analysis and neural networks both yielded high accuracy. Both these analytical approaches are fast and could be applied with an on-line scatterometer inspection tool. In addition, both methods were also found to be robust with respect to data acquisition problems. Therefore, scatterometry integrated with either discriminant or neural network analysis is a promising alternative to destructive sampling and off-line inspection by scanning electron microscopy for statistical process control.

Krukar, Richard; Kornblit, Avi; Clark, Linda A.; Kruskal, Joseph; Lambert, Diane; Reitman, Edward A.; Gottscho, Richard A.

1993-09-01

146

Deeply Virtual Compton Scattering and Meson Production at Jlab/CLAS  

SciTech Connect

This report reviews the recent experimental results from the CLAS collaboration (Hall B of Jefferson Lab, or JLab) on Deeply Virtual Compton Scattering (DVCS) and Deeply Virtual Meson Production (DVMP) and discusses their interpretation in the framework of Generalized Parton Distributions (GPDs). The impact of the experimental data on the applicability of the GPD mechanism to these exclusive reactions is discussed. Initial results obtained from JLab 6 GeV data indicate that DVCS might already be interpretable in this framework while GPD models fail to describe the exclusive meson production (DVMP) data with the GPD parameterizations presently used. An exception is the {phi} meson production for which the GPD mechanism appears to apply. The recent global analyses aiming to extract GPDs from fitting DVCS CLAS and world data are discussed. The GPD experimental program at CLAS12, planned with the upcoming 12 GeV upgrade of JLab, is briefly presented.

Hyon-Suk Jo

2012-04-01

147

Measurement of photon production in the very forward direction in deep-inelastic scattering at HERA  

NASA Astrophysics Data System (ADS)

The production of photons at very small angles with respect to the proton beam direction is studied in deep-inelastic positron-proton scattering at HERA. The data are taken with the H1 detector in the years 2006 and 2007 and correspond to an integrated luminosity of 126 pb-1. The analysis covers the range of negative four momentum transfer squared at the positron vertex 6< Q 2<100 GeV2 and inelasticity 0.05< y<0.6. Cross sections are measured for the most energetic photon with pseudorapidity ?>7.9 as a function of its transverse momentum pT^{lead} and longitudinal momentum fraction of the incoming proton xL^{lead}. In addition, the cross sections are studied as a function of the sum of the longitudinal momentum fraction xL^{sum} of all photons in the pseudorapidity range ?>7.9. The cross sections are normalised to the inclusive deep-inelastic scattering cross section and compared to the predictions of models of deep-inelastic scattering and models of the hadronic interactions of high energy cosmic rays.

Aaron, F. D.; Alexa, C.; Andreev, V.; Backovic, S.; Baghdasaryan, A.; Baghdasaryan, S.; Barrelet, E.; Bartel, W.; Begzsuren, K.; Belousov, A.; Belov, P.; Bizot, J. C.; Boudry, V.; Bozovic-Jelisavcic, I.; Bracinik, J.; Brandt, G.; Brinkmann, M.; Brisson, V.; Britzger, D.; Bruncko, D.; Bunyatyan, A.; Buschhorn, G.; Bystritskaya, L.; Campbell, A. J.; Cantun Avila, K. B.; Ceccopieri, F.; Cerny, K.; Cerny, V.; Chekelian, V.; Contreras, J. G.; Coughlan, J. A.; Cvach, J.; Dainton, J. B.; Daum, K.; Delcourt, B.; Delvax, J.; De Wolf, E. A.; Diaconu, C.; Dobre, M.; Dodonov, V.; Dossanov, A.; Dubak, A.; Eckerlin, G.; Egli, S.; Eliseev, A.; Elsen, E.; Favart, L.; Fedotov, A.; Felst, R.; Feltesse, J.; Ferencei, J.; Fischer, D.-J.; Fleischer, M.; Fomenko, A.; Gabathuler, E.; Gayler, J.; Ghazaryan, S.; Glazov, A.; Goerlich, L.; Gogitidze, N.; Gouzevitch, M.; Grab, C.; Grebenyuk, A.; Greenshaw, T.; Grell, B. R.; Grindhammer, G.; Habib, S.; Haidt, D.; Helebrant, C.; Henderson, R. C. W.; Hennekemper, E.; Henschel, H.; Herbst, M.; Herrera, G.; Hildebrandt, M.; Hiller, K. H.; Hoffmann, D.; Horisberger, R.; Hreus, T.; Huber, F.; Jacquet, M.; Janssen, X.; Jönsson, L.; Jung, H.; Kapichine, M.; Kenyon, I. R.; Kiesling, C.; Klein, M.; Kleinwort, C.; Kluge, T.; Kogler, R.; Kostka, P.; Kraemer, M.; Kretzschmar, J.; Krüger, K.; Landon, M. P. J.; Lange, W.; Laštovi?ka-Medin, G.; Laycock, P.; Lebedev, A.; Lendermann, V.; Levonian, S.; Lipka, K.; List, B.; List, J.; Lopez-Fernandez, R.; Lubimov, V.; Lytkin, L.; Makankine, A.; Malinovski, E.; Marage, P.; Martyn, H.-U.; Maxfield, S. J.; Mehta, A.; Meyer, A. B.; Meyer, H.; Meyer, J.; Mikocki, S.; Milcewicz-Mika, I.; Moreau, F.; Morozov, A.; Morris, J. V.; Mudrinic, M.; Müller, K.; Naumann, Th.; Newman, P. R.; Niebuhr, C.; Nikitin, D.; Nowak, G.; Nowak, K.; Olsson, J. E.; Ozerov, D.; Pahl, P.; Palichik, V.; Panagoulias, I.; Pandurovic, M.; Papadopoulou, Th.; Pascaud, C.; Patel, G. D.; Perez, E.; Petrukhin, A.; Picuric, I.; Piec, S.; Pirumov, H.; Pitzl, D.; Pla?akyt?, R.; Pokorny, B.; Polifka, R.; Povh, B.; Radescu, V.; Raicevic, N.; Ravdandorj, T.; Reimer, P.; Rizvi, E.; Robmann, P.; Roosen, R.; Rostovtsev, A.; Rotaru, M.; Ruiz Tabasco, J. E.; Rusakov, S.; Šálek, D.; Sankey, D. P. C.; Sauter, M.; Sauvan, E.; Schmitt, S.; Schoeffel, L.; Schöning, A.; Schultz-Coulon, H.-C.; Sefkow, F.; Shtarkov, L. N.; Shushkevich, S.; Sloan, T.; Smiljanic, I.; Soloviev, Y.; Sopicki, P.; South, D.; Spaskov, V.; Specka, A.; Staykova, Z.; Steder, M.; Stella, B.; Stoicea, G.; Straumann, U.; Sykora, T.; Thompson, P. D.; Tran, T. H.; Traynor, D.; Truöl, P.; Tsakov, I.; Tseepeldorj, B.; Turnau, J.; Urban, K.; Valkárová, A.; Vallée, C.; Van Mechelen, P.; Vazdik, Y.; Wegener, D.; Wünsch, E.; Žá?ek, J.; Zálešák, J.; Zhang, Z.; Zhokin, A.; Zohrabyan, H.; Zomer, F.

2011-10-01

148

Coherent anti-Stokes Raman scattering (CARS) detection or hot atom reaction product internal energy distributions  

SciTech Connect

Coherent anti-Stokes Raman spectroscopy (CARS) is being utilized to investigate the rovibrational energy distributions produced by reactive and nonreactive collisions of translationally hot atoms with simple molecules. Translationally hot H atoms are produced by ArF laser photolysis of HBr. Using CARS we have monitored, in a state-specific and time-resolved manner, rotational excitation of HBr (v = 0), vibrational excitation of HBr and H/sub 2/, rovibrational excitation of H/sub 2/ produced by the reaction H + HBr ..-->.. H/sub 2/ + Br, and Br atom production by photolysis of HBr.

Quick, C.R. Jr.; Moore, D.S.

1983-01-01

149

Three-dimensional Monte Carlo simulation of gamma-ray scattering and production in the atmosphere  

NASA Astrophysics Data System (ADS)

Results are reported from Monte Carlo numerical simulations of atmospheric gamma-ray scattering and production. The basic physical principles involved in the construction of the models are reviewed, and results are presented in extensive graphs for low-energy gamma rays with the spectra of gamma-ray bursts, solar flares, the Crab pulsar, and 511-keV line radiation. It is shown that the model accurately reproduces the characteristics of atmospheric albedo radiation, including details of the angular distribution. The potential applicability of the Monte Carlo technique to studies of the near-earth radiation environment is indicated.

Morris, Daniel J.

1989-05-01

150

A phenomenological study of photon production in low energy neutrino nucleon scattering  

SciTech Connect

Low energy photon production is an important background to many current and future precision neutrino experiments. We present a phenomenological study of t-channel radiative corrections to neutral current neutrino nucleus scattering. After introducing the relevant processes and phenomenological coupling constants, we will explore the derived energy and angular distributions as well as total cross-section predictions along with their estimated uncertainties. This is supplemented throughout with comments on possible experimental signatures and implications. We conclude with a general discussion of the analysis in the context of complimentary methodologies. This is based on a talk presented at the DPF 2009 meeting in Detroit MI.

Jenkins, James P [Los Alamos National Laboratory; Goldman, Terry J [Los Alamos National Laboratory

2009-01-01

151

Muon production in low-energy electron-nucleon and electron-nucleus scattering  

Microsoft Academic Search

Recently, muon production in electron-proton scattering has been suggested as a possible candidate reaction for the identification of lepton-flavor violation due to physics beyond the standard model. Here we point out that the standard-model processes e-p-->mu-pnu¯munue and e-p-->e-nmu+numu can cloud potential beyond-the-standard-model signals in ep collisions. We find that standard-model ep-->muX cross sections exceed those from lepton-flavor-violating operators by several

Prashanth Jaikumar; Daniel R. Phillips; Lucas Platter; Madappa Prakash

2007-01-01

152

Jet production in deep-inelastic muon scattering at 490 GeV  

SciTech Connect

Measurements of jet rates in deep-inelastic muon scattering are presented. The JADE algorithm is used to define jets in the kinematic region 9 < W < 33 GeV. Data taken on a proton target are analyzed within the QCD framework, with the goal of extracting [alpha][sub s]. Results on the Q[sup 2] dependence of the average transverse momentum of jets are used to demonstrate the running of the strong coupling constant [alpha][sub s]. In addition, first measurements of the production of jets from heavy nuclei in the region x[sub B[sub j

Melanson, H.L.

1993-06-01

153

Study of ?(1385) and ?(1321) hyperon and antihyperon production in deep inelastic muon scattering  

NASA Astrophysics Data System (ADS)

Large samples of ?, ?(1385) and ?(1321) hyperons produced in the deep-inelastic muon scattering off a 6LiD target were collected with the COMPASS experimental setup at CERN. The relative yields of ?(1385)+, ?(1385)-, , , ?(1321)-, and hyperons decaying into were measured. The ratios of heavy-hyperon to ? and heavy-antihyperon to were found to be in the range 3.8 % to 5.6 % with a relative uncertainty of about 10 %. They were used to tune the parameters relevant for strange particle production of the LEPTO Monte Carlo generator.

Adolph, C.; Alekseev, M. G.; Alexakhin, V. Y.; Alexandrov, Y.; Alexeev, G. D.; Amoroso, A.; Austregesilo, A.; Bade?ek, B.; Balestra, F.; Barth, J.; Baum, G.; Bedfer, Y.; Berlin, A.; Bernhard, J.; Bertini, R.; Bicker, K.; Bieling, J.; Birsa, R.; Bisplinghoff, J.; Bordalo, P.; Bradamante, F.; Braun, C.; Bravar, A.; Bressan, A.; Büchele, M.; Burtin, E.; Capozza, L.; Chiosso, M.; Chung, S. U.; Cicuttin, A.; Crespo, M. L.; Dalla Torre, S.; Dasgupta, S. S.; Dasgupta, S.; Denisov, O. Y.; Donskov, S. V.; Doshita, N.; Duic, V.; Dünnweber, W.; Dziewiecki, M.; Efremov, A.; Elia, C.; Eversheim, P. D.; Eyrich, W.; Faessler, M.; Ferrero, A.; Filin, A.; Finger, M.; Finger, M.; Fischer, H.; Franco, C.; du Fresne von Hohenesche, N.; Friedrich, J. M.; Frolov, V.; Garfagnini, R.; Gautheron, F.; Gavrichtchouk, O. P.; Gerassimov, S.; Geyer, R.; Giorgi, M.; Gnesi, I.; Gobbo, B.; Goertz, S.; Grabmüller, S.; Grasso, A.; Grube, B.; Gushterski, R.; Guskov, A.; Guthörl, T.; Haas, F.; von Harrach, D.; Heinsius, F. H.; Herrmann, F.; Heß, C.; Hinterberger, F.; Höppner, C.; Horikawa, N.; d'Hose, N.; Huber, S.; Ishimoto, S.; Ivanshin, Y.; Iwata, T.; Jahn, R.; Jary, V.; Jasinski, P.; Joosten, R.; Kabuß, E.; Kang, D.; Ketzer, B.; Khaustov, G. V.; Khokhlov, Y. A.; Kisselev, Y.; Klein, F.; Klimaszewski, K.; Koivuniemi, J. H.; Kolosov, V. N.; Kondo, K.; Königsmann, K.; Konorov, I.; Konstantinov, V. F.; Kotzinian, A. M.; Kouznetsov, O.; Krämer, M.; Kroumchtein, Z. V.; Kuchinski, N.; Kunne, F.; Kurek, K.; Kurjata, R. P.; Lednev, A. A.; Lehmann, A.; Levorato, S.; Lichtenstadt, J.; Maggiora, A.; Magnon, A.; Makke, N.; Mallot, G. K.; Mann, A.; Marchand, C.; Martin, A.; Marzec, J.; Matsuda, H.; Matsuda, T.; Meshcheryakov, G.; Meyer, W.; Michigami, T.; Mikhailov, Y. V.; Miyachi, Y.; Morreale, A.; Nagaytsev, A.; Nagel, T.; Nerling, F.; Neubert, S.; Neyret, D.; Nikolaenko, V. I.; Novy, J.; Nowak, W.-D.; Nunes, A. S.; Olshevsky, A. G.; Ostrick, M.; Panknin, R.; Panzieri, D.; Parsamyan, B.; Paul, S.; Piragino, G.; Platchkov, S.; Pochodzalla, J.; Polak, J.; Polyakov, V. A.; Pretz, J.; Quaresma, M.; Quintans, C.; Ramos, S.; Reicherz, G.; Rocco, E.; Rodionov, V.; Rondio, E.; Rossiyskaya, N. S.; Ryabchikov, D. I.; Samoylenko, V. D.; Sandacz, A.; Sapozhnikov, M. G.; Sarkar, S.; Savin, I. A.; Sbrizzai, G.; Schiavon, P.; Schill, C.; Schlüter, T.; Schmidt, A.; Schmidt, K.; Schmitt, L.; Schmïden, H.; Schönning, K.; Schopferer, S.; Schott, M.; Shevchenko, O. Y.; Silva, L.; Sinha, L.; Sirtl, S.; Sosio, S.; Sozzi, F.; Srnka, A.; Steiger, L.; Stolarski, M.; Sulc, M.; Sulej, R.; Suzuki, H.; Sznajder, P.; Takekawa, S.; Ter Wolbeek, J.; Tessaro, S.; Tessarotto, F.; Thibaud, F.; Uhl, S.; Uman, I.; Vandenbroucke, M.; Virius, M.; Wang, L.; Weisrock, T.; Wilfert, M.; Windmolders, R.; Wi?licki, W.; Wollny, H.; Zaremba, K.; Zavertyaev, M.; Zemlyanichkina, E.; Zhuravlev, N.; Ziembicki, M.

2013-10-01

154

Muon production in low-energy electron-nucleon and electron-nucleus scattering  

NASA Astrophysics Data System (ADS)

Recently, muon production in electron-proton scattering has been suggested as a possible candidate reaction for the identification of lepton-flavor violation due to physics beyond the standard model. Here we point out that the standard-model processes e-p??-p?¯??e and e-p?e-n?+?? can cloud potential beyond-the-standard-model signals in ep collisions. We find that standard-model ep??X cross sections exceed those from lepton-flavor-violating operators by several orders of magnitude. We also discuss the possibility of using a nuclear target to enhance the ep??X signal.

Jaikumar, Prashanth; Phillips, Daniel R.; Platter, Lucas; Prakash, Madappa

2007-12-01

155

Measurement of beauty production in deep inelastic scattering at HERA using decays into electrons  

NASA Astrophysics Data System (ADS)

The results from a recent analysis on beauty production in deep inelastic scattering at HERA using decays into electrons from the ZEUS collaboration are presented. The fractions of events containing b quarks were extracted from a likelihood fit using variables sensitive to electron identification as well as to semileptonic decays. Total and differential cross sections were measured and compared with next-to-leading-order QCD calculations. The beauty contribution to the proton structure function F_2 was extracted from the double-differential cross sections.

Shehzadi, R.

156

Heavy Quarkonium Production in Single Transverse Polarized HighEnergy Scattering  

SciTech Connect

We formulate the single transverse spin asymmetry in heavyquarkoniumproduction in lepton-nucleon and nucleon-nucleon collisionsinthe non-relativistic limit. We findthat the asymmetry is very sensitiveto the production mechanism. The finalstate interactions with the heavyquark and antiquark cancel out among themselves whenthe pair are producedin a color-single configuration, or cancel out with the initialstateinteraction in pp scattering when they are in color-octet. As aconsequence, the asymmetry is nonzero in ep collisions only in thecolor-octet model, whereas in pp collisions only in the color-singletmodel.

Yuan, Feng

2008-01-17

157

[Photoinduced production of reactive oxygen species by retinal derivatives and conjugates].  

PubMed

The formation of reactive oxygen species (ROS) during all trans-retinal illumination was studied by ESR. The quantity of ROS was estimated by the ESR signal of a spin adduct of DEPMPO (5-dietoxyphosphoryl-5 methyl-1-pirroline-N-oxide). The ESR signal was found to be a superposition of the adducts: 80%--superoxide anion radical, 15%--hydroxyl radical and 5%--an unknown radical. It was shown that the addition of an equimolar albumin concentration resulted in the 5-fold decrease of the relative quantum yield for ROS generation, and a 4-fold albumin excess led to decreased ROS production by 30-fold. It is supposed that ATR and A2E in the photoreceptor membrane are the sources of photodamage induced by ROS. ATR in the cell is known to be transported by interphotoreceptor retinal binding proteins that belong to the albumin family. The ATR binding with proteins is supposed to prevent the ROS production in the photoreceptor cell and thus produces the light damage protection action. PMID:23755549

Aboltin, P V; Shevchenko, T F; Shumaev, K B; Kalamkarov, G R

158

Conversion of natively unstructured ?-synuclein to its ?-helical conformation significantly attenuates production of reactive oxygen species.  

PubMed

The intracellular ?-synuclein (?-syn) protein, whose conformational change and aggregation have been closely linked to the pathology of Parkingson's disease (PD), is highly populated at the presynaptic termini and remains there in the ?-helical conformation. In this study, circular dichroism confirmed that natively unstructured ?-syn in aqueous solution was transformed to its ?-helical conformation upon addition of trifluoroethanol (TFE). Electrochemical and UV-visible spectroscopic experiments reveal that both Cu (I) and Cu (II) are stabilized, with the former being stabilized by about two orders of magnitude. Compared to unstructured ?-syn (Binolfi et al., J. Am. Chem. Soc. 133 (2011) 194-196), ?-helical ?-syn stabilizes Cu (I) by more than three orders of magnitude. Through the measurements of H(2)O(2) and hydroxyl radicals (OH) in solutions containing different forms of Cu (II) (free and complexed by unstructured or ?-helical ?-syn), we demonstrate that the significantly enhanced Cu (I) binding affinity helps inhibit the production of highly toxic reactive oxygen species, especially the hydroxyl radicals. Our study provides strong evidence that, as a possible means to prevent neuronal cell damage, conversion of the natively unstructured ?-syn to its ?-helical conformation in vivo could significantly attenuate the copper-modulated ROS production. PMID:23123341

Zhou, Binbin; Hao, Yuanqiang; Wang, Chengshan; Li, Ding; Liu, You-Nian; Zhou, Feimeng

2012-09-08

159

DNase I Inhibits a Late Phase of Reactive Oxygen Species Production in Neutrophils  

PubMed Central

Neutrophils kill bacteria on extracellular complexes of DNA fibers and bactericidal proteins known as neutrophil extracellular traps (NETs). The NET composition and the bactericidal mechanisms they use are not fully understood. Here, we show that treatment with deoxyribonuclease (DNase I) impairs a late oxidative response elicited by Gram-positive and Gram-negative bacteria and also by phorbol ester. Isoluminol-dependent chemiluminescence elicited by opsonized Listeria monocytogenes-stimulated neutrophils was inhibited by DNase I, and the DNase inhibitory effect was also evident when phagocytosis was blocked, suggesting that DNase inhibits an extracellular mechanism of reactive oxygen species (ROS) generation. The DNase inhibitory effect was independent of actin polymerization. Phagocytosis and cell viability were not impaired by DNase I. Immunofluorescence analysis shows that myeloperoxidase is present on NETs. Furthermore, granular proteins were detected in NETs from Rab27a-deficient neutrophils which have deficient exocytosis, suggesting that exocytosis and granular protein distribution on NETs proceed by independent mechanisms. NADPH oxidase subunits were also detected on NETs, and the detection of extracellular trap-associated NADPH oxidase subunits was abolished by treatment with DNase I and dependent on cell stimulation. In vitro analyses demonstrate that MPO and NADPH oxidase activity are not directly inhibited by DNase I, suggesting that its effect on ROS production depends on NET disassembly. Altogether, our data suggest that inhibition of ROS production by microorganism-derived DNase would contribute to their ability to evade killing.

Munafo, Daniela B.; Johnson, Jennifer L.; Brzezinska, Agnieszka A.; Ellis, Beverly A.; Wood, Malcolm R.; Catz, Sergio D.

2009-01-01

160

Seminal leukocyte concentration and related specific reactive oxygen species production in patients with male accessory gland infections  

Microsoft Academic Search

The aim of this study was to determine whether differences occur in seminal concentrations of white blood corpuscles (sWBC) and whether WBC production of reactive oxygen species (ROS) is related to the infiltration of one or more male sexual glands. We studied 70 infertile patients affected by bacterial male accessory gland infections (MAGI) who were divided clinically and, by ultrasound

E. Vicari

1999-01-01

161

Protective effect of flavonoids against reactive oxygen species production in sickle cell anemia patients treated with hydroxyurea  

PubMed Central

Objective The aim of this study was to evaluate the protective effects of quercetin, rutin, hesperidin and myricetin against reactive oxygen species production with the oxidizing action of tert-butylhydroperoxide in erythrocytes from normal subjects and sickle cell anemia carriers treated with hydroxyurea. Methods Detection of intracellular reactive oxygen species was carried out using a liposoluble probe, 2',7'-dichlorfluorescein-diacetate (DCFH-DA). A 10% erythrocyte suspension was incubated with flavonoids (quercetin, rutin, hesperidin or myricetin; 30, 50, and 100 µmol/L), and then incubated with tert-butylhydroperoxide (75 µmol/L). Untreated samples were used as controls. Results Red blood cell exposure to tert-butylhydroperoxide resulted in significant increases in the generation of intracellular reactive oxygen species compared to basal levels. Reactive oxygen species production was significantly inhibited when red blood cells were pre-incubated with flavonoids, both in normal individuals and in patients with sickle cell anemia. Quercetin and rutin had the highest antioxidant activity, followed by myricetin and hesperidin. CONCLUSION: Flavonoids, in particular quercetin and rutin, showed better antioxidant effects against damage caused by excess reactive oxygen species characteristic of sickle cell anemia. Results obtained with patients under treatment with hydroxyurea suggest an additional protective effect when associated with the use of flavonoids.

Henneberg, Railson; Otuki, Michel Fleith; Furman, Aline Emmer Ferreira; Hermann, Priscila; do Nascimento, Aguinaldo Jose; Leonart, Maria Suely Soares

2013-01-01

162

Extending cassava root shelf life via reduction of reactive oxygen species production.  

PubMed

One of the major constraints facing the large-scale production of cassava (Manihot esculenta) roots is the rapid postharvest physiological deterioration (PPD) that occurs within 72 h following harvest. One of the earliest recognized biochemical events during the initiation of PPD is a rapid burst of reactive oxygen species (ROS) accumulation. We have investigated the source of this oxidative burst to identify possible strategies to limit its extent and to extend cassava root shelf life. We provide evidence for a causal link between cyanogenesis and the onset of the oxidative burst that triggers PPD. By measuring ROS accumulation in transgenic low-cyanogen plants with and without cyanide complementation, we show that PPD is cyanide dependent, presumably resulting from a cyanide-dependent inhibition of respiration. To reduce cyanide-dependent ROS production in cassava root mitochondria, we generated transgenic plants expressing a codon-optimized Arabidopsis (Arabidopsis thaliana) mitochondrial alternative oxidase gene (AOX1A). Unlike cytochrome c oxidase, AOX is cyanide insensitive. Transgenic plants overexpressing AOX exhibited over a 10-fold reduction in ROS accumulation compared with wild-type plants. The reduction in ROS accumulation was associated with a delayed onset of PPD by 14 to 21 d after harvest of greenhouse-grown plants. The delay in PPD in transgenic plants was also observed under field conditions, but with a root biomass yield loss in the highest AOX-expressing lines. These data reveal a mechanism for PPD in cassava based on cyanide-induced oxidative stress as well as PPD control strategies involving inhibition of ROS production or its sequestration. PMID:22711743

Zidenga, Tawanda; Leyva-Guerrero, Elisa; Moon, Hangsik; Siritunga, Dimuth; Sayre, Richard

2012-06-18

163

Reactive Oxygen Species Production by Forward and Reverse Electron Fluxes in the Mitochondrial Respiratory Chain  

PubMed Central

Reactive oxygen species (ROS) produced in the mitochondrial respiratory chain (RC) are primary signals that modulate cellular adaptation to environment, and are also destructive factors that damage cells under the conditions of hypoxia/reoxygenation relevant for various systemic diseases or transplantation. The important role of ROS in cell survival requires detailed investigation of mechanism and determinants of ROS production. To perform such an investigation we extended our rule-based model of complex III in order to account for electron transport in the whole RC coupled to proton translocation, transmembrane electrochemical potential generation, TCA cycle reactions, and substrate transport to mitochondria. It fits respiratory electron fluxes measured in rat brain mitochondria fueled by succinate or pyruvate and malate, and the dynamics of NAD+ reduction by reverse electron transport from succinate through complex I. The fitting of measured characteristics gave an insight into the mechanism of underlying processes governing the formation of free radicals that can transfer an unpaired electron to oxygen-producing superoxide and thus can initiate the generation of ROS. Our analysis revealed an association of ROS production with levels of specific radicals of individual electron transporters and their combinations in species of complexes I and III. It was found that the phenomenon of bistability, revealed previously as a property of complex III, remains valid for the whole RC. The conditions for switching to a state with a high content of free radicals in complex III were predicted based on theoretical analysis and were confirmed experimentally. These findings provide a new insight into the mechanisms of ROS production in RC.

Selivanov, Vitaly A.; Votyakova, Tatyana V.; Pivtoraiko, Violetta N.; Zeak, Jennifer; Sukhomlin, Tatiana; Trucco, Massimo; Roca, Josep; Cascante, Marta

2011-01-01

164

Cell death and production of reactive oxygen species by murine macrophages after short term exposure to phthalates  

Microsoft Academic Search

The effects of four phthalates, i.e., di-2-ethylhexyl phthalate (DEHP), butyl benzyl phthalate (BBP), dibutyl phthalate (DBP) and diisobutyl phthalate (DIBP) on necrotic and apoptotic cell death, and production of reactive oxygen species (ROS) were studied on mouse macrophage cell line RAW 264.7. All the phthalates caused negligible and non-dose-dependent ROS production compared to control experiment. DEHP and BBP did not

J. Naarala; A. Korpi

2009-01-01

165

Measurement of leading neutron production in deep-inelastic scattering at HERA  

NASA Astrophysics Data System (ADS)

The production of leading neutrons, where the neutron carries a large fraction x L of the incoming proton’s longitudinal momentum, is studied in deep-inelastic positron-proton scattering at HERA. The data were taken with the H1 detector in the years 2006 and 2007 and correspond to an integrated luminosity of 122 pb-1. The semi-inclusive cross section is measured in the phase space defined by the photon virtuality 6< Q 2<100 GeV2, Bjorken scaling variable 1.5?10-4< x<3?10-2, longitudinal momentum fraction 0.32< x L <0.95 and neutron transverse momentum p T <0.2 GeV. The leading neutron structure function, F2^{LN(3)}(Q2,x,xL), and the fraction of deep-inelastic scattering events containing a leading neutron are studied as a function of Q 2, x and x L . Assuming that the pion exchange mechanism dominates leading neutron production, the data provide constraints on the shape of the pion structure function.

Aaron, F. D.; Alexa, C.; Andreev, V.; Antunovic, B.; Backovic, S.; Baghdasaryan, A.; Barrelet, E.; Bartel, W.; Begzsuren, K.; Belousov, A.; Bizot, J. C.; Boudry, V.; Bozovic-Jelisavcic, I.; Bracinik, J.; Brandt, G.; Brinkmann, M.; Brisson, V.; Bruncko, D.; Bunyatyan, A.; Buschhorn, G.; Bystritskaya, L.; Campbell, A. J.; Cantun Avila, K. B.; Cerny, K.; Cerny, V.; Chekelian, V.; Cholewa, A.; Contreras, J. G.; Coughlan, J. A.; Cozzika, G.; Cvach, J.; Dainton, J. B.; Daum, K.; Deák, M.; Delcourt, B.; Delvax, J.; de Wolf, E. A.; Diaconu, C.; Dodonov, V.; Dossanov, A.; Dubak, A.; Eckerlin, G.; Efremenko, V.; Egli, S.; Eliseev, A.; Elsen, E.; Falkiewicz, A.; Favart, L.; Fedotov, A.; Felst, R.; Feltesse, J.; Ferencei, J.; Fischer, D.-J.; Fleischer, M.; Fomenko, A.; Gabathuler, E.; Gayler, J.; Ghazaryan, S.; Glazov, A.; Glushkov, I.; Goerlich, L.; Gogitidze, N.; Gouzevitch, M.; Grab, C.; Greenshaw, T.; Grell, B. R.; Grindhammer, G.; Habib, S.; Haidt, D.; Helebrant, C.; Henderson, R. C. W.; Hennekemper, E.; Henschel, H.; Herbst, M.; Herrera, G.; Hildebrandt, M.; Hiller, K. H.; Hoffmann, D.; Horisberger, R.; Hreus, T.; Jacquet, M.; Janssen, X.; Jönsson, L.; Jung, A. W.; Jung, H.; Kapichine, M.; Katzy, J.; Kenyon, I. R.; Kiesling, C.; Klein, M.; Kleinwort, C.; Kluge, T.; Knutsson, A.; Kogler, R.; Kostka, P.; Kraemer, M.; Krastev, K.; Kretzschmar, J.; Kropivnitskaya, A.; Krüger, K.; Kutak, K.; Landon, M. P. J.; Lange, W.; Laštovi?ka-Medin, G.; Laycock, P.; Lebedev, A.; Lendermann, V.; Levonian, S.; Li, G.; Lipka, K.; Liptaj, A.; List, B.; List, J.; Loktionova, N.; Lopez-Fernandez, R.; Lubimov, V.; Lytkin, L.; Makankine, A.; Malinovski, E.; Marage, P.; Marti, L.; Martyn, H.-U.; Maxfield, S. J.; Mehta, A.; Meyer, A. B.; Meyer, H.; Meyer, H.; Meyer, J.; Mikocki, S.; Milcewicz-Mika, I.; Moreau, F.; Morozov, A.; Morris, J. V.; Mozer, M. U.; Mudrinic, M.; Müller, K.; Murín, P.; Naumann, Th.; Newman, P. R.; Niebuhr, C.; Nikiforov, A.; Nikitin, D.; Nowak, G.; Nowak, K.; Olsson, J. E.; Osman, S.; Ozerov, D.; Pahl, P.; Palichik, V.; Panagoulias, I.; Pandurovic, M.; Papadopoulou, Th.; Pascaud, C.; Patel, G. D.; Pejchal, O.; Perez, E.; Petrukhin, A.; Picuric, I.; Piec, S.; Pitzl, D.; Pla?akyt?, R.; Pokorny, B.; Polifka, R.; Povh, B.; Radescu, V.; Rahmat, A. J.; Raicevic, N.; Raspiareza, A.; Ravdandorj, T.; Reimer, P.; Rizvi, E.; Robmann, P.; Roland, B.; Roosen, R.; Rostovtsev, A.; Rotaru, M.; Ruiz Tabasco, J. E.; Rusakov, S.; Šálek, D.; Sankey, D. P. C.; Sauter, M.; Sauvan, E.; Schmitt, S.; Schoeffel, L.; Schöning, A.; Schultz-Coulon, H.-C.; Sefkow, F.; Shaw-West, R. N.; Shtarkov, L. N.; Shushkevich, S.; Sloan, T.; Smiljanic, I.; Soloviev, Y.; Sopicki, P.; South, D.; Spaskov, V.; Specka, A.; Staykova, Z.; Steder, M.; Stella, B.; Stoicea, G.; Straumann, U.; Sunar, D.; Sykora, T.; Tchoulakov, V.; Thompson, G.; Thompson, P. D.; Toll, T.; Tomasz, F.; Tran, T. H.; Traynor, D.; Trinh, T. N.; Truöl, P.; Tsakov, I.; Tseepeldorj, B.; Turnau, J.; Urban, K.; Valkárová, A.; Vallée, C.; van Mechelen, P.; Vargas Trevino, A.; Vazdik, Y.; Vinokurova, S.; Volchinski, V.; von den Driesch, M.; Wegener, D.; Wissing, C.; Wünsch, E.; Žá?ek, J.; Zálešák, J.; Zhang, Z.; Zhokin, A.; Zimmermann, T.; Zohrabyan, H.; Zomer, F.; H1 Collaboration

2010-08-01

166

Multi-jet production rates in deep-inelastic muon-proton scattering  

SciTech Connect

Measurements of forward multi-jet production rates in deep-inelastic muonproton scattering are presented. Data were taken with a 490 GeV muon beam incident on a hydrogen target. Jets were defined using the JADE jet finding algorithm. The measured rates are presented as function of W, the hadronic center-of-mass energy and the jet resolution parameter, y[sub cut], in energies up to W=33 GeV. Good agreement is found in comparisons with predictions of the QCD-inspired Lund Monte Carlo models. Non-perturbative QCD production mechanisms, inside the Lund Model, can not reproduce the results for energies greater than W [approx equal] 20 GeV. Sensitivities of the jet rate measurements to the low x (x [approx equal] 0.02) gluon content of the nucleon and the evolution of [alpha][sub s], are studied.

Salgado, C.W.

1992-10-01

167

Multi-jet production rates in deep-inelastic muon-proton scattering  

SciTech Connect

Measurements of forward multi-jet production rates in deep-inelastic muonproton scattering are presented. Data were taken with a 490 GeV muon beam incident on a hydrogen target. Jets were defined using the JADE jet finding algorithm. The measured rates are presented as function of W, the hadronic center-of-mass energy and the jet resolution parameter, y{sub cut}, in energies up to W=33 GeV. Good agreement is found in comparisons with predictions of the QCD-inspired Lund Monte Carlo models. Non-perturbative QCD production mechanisms, inside the Lund Model, can not reproduce the results for energies greater than W {approx_equal} 20 GeV. Sensitivities of the jet rate measurements to the low x (x {approx_equal} 0.02) gluon content of the nucleon and the evolution of {alpha}{sub s}, are studied.

Salgado, C.W.; E665 Collaboration

1992-10-01

168

Measurement of D + and ? c + production in deep inelastic scattering at HERA  

NASA Astrophysics Data System (ADS)

Charm production in deep inelastic scattering has been measured with the ZEUS detector at HERA using an integrated luminosity of 120 pb-1. The hadronic decay channels D + ? K S 0 ? +, ? c + ? pK S 0 and ? c + ? ? ? +, and their charge conjugates, were reconstructed. The presence of a neutral strange hadron in the final state reduces the combinatorial background and extends the measured sensitivity into the low transverse momentum region. The kinematic range is 0 < p T ( D +, ? c +) < 10 GeV, | ?( D +, ? c +)| < 1 .6, 1.5 < Q 2 < 1000 GeV2 and 0 .02 < y < 0.7. Inclusive and differential cross sections for the production of D + mesons are compared to next-to-leading-order QCD predictions. The fraction of c quarks hadronising into ? c + baryons is extracted.

Abramowicz, H.; Abt, I.; Adamczyk, L.; Adamus, M.; Aggarwal, R.; Antonelli, S.; Antonioli, P.; Antonov, A.; Arneodo, M.; Aushev, V.; Aushev, Y.; Bachynska, O.; Bamberger, A.; Barakbaev, A. N.; Barbagli, G.; Bari, G.; Barreiro, F.; Bartsch, D.; Basile, M.; Behnke, O.; Behr, J.; Behrens, U.; Bellagamba, L.; Bertolin, A.; Bhadra, S.; Bindi, M.; Blohm, C.; Bold, T.; Boos, E. G.; Borodin, M.; Borras, K.; Boscherini, D.; Bot, D.; Boutle, S. K.; Brock, I.; Brownson, E.; Brugnera, R.; Brümmer, N.; Bruni, A.; Bruni, G.; Brzozowska, B.; Bussey, P. J.; Butterworth, J. M.; Bylsma, B.; Caldwell, A.; Capua, M.; Carlin, R.; Catterall, C. D.; Chekanov, S.; Chwastowski, J.; Ciborowski, J.; Ciesielski, R.; Cifarelli, L.; Cindolo, F.; Contin, A.; Cooper-Sarkar, A. M.; Coppola, N.; Corradi, M.; Corriveau, F.; Costa, M.; D'Agostini, G.; Dal Corso, F.; de Favereau, J.; Del Peso, J.; Dementiev, R. K.; de Pasquale, S.; Derrick, M.; Devenish, R. C. E.; Dobur, D.; Dolgoshein, B. A.; Doyle, A. T.; Drugakov, V.; Durkin, L. S.; Dusini, S.; Eisenberg, Y.; Ermolov, P. F.; Eskreys, A.; Fang, S.; Fazio, S.; Ferrando, J.; Ferrero, M. I.; Figiel, J.; Forrest, M.; Foster, B.; Fourletov, S.; Gach, G.; Galas, A.; Gallo, E.; Garfagnini, A.; Geiser, A.; Gialas, I.; Gladilin, L. K.; Gladkov, D.; Glasman, C.; Gogota, O.; Golubkov, Yu. A.; Göttlicher, P.; Grabowska-Bo?d, I.; Grebenyuk, J.; Gregor, I.; Grigorescu, G.; Grzelak, G.; Gwenlan, C.; Haas, T.; Hain, W.; Hamatsu, R.; Hart, J. C.; Hartmann, H.; Hartner, G.; Hilger, E.; Hochman, D.; Holm, U.; Hori, R.; Horton, K.; Hüttmann, A.; Iacobucci, G.; Ibrahim, Z. A.; Iga, Y.; Ingbir, R.; Ishitsuka, M.; Jakob, H.-P.; Januschek, F.; Jimenez, M.; Jones, T. W.; Jüngst, M.; Kadenko, I.; Kahle, B.; Kamaluddin, B.; Kananov, S.; Kanno, T.; Karshon, U.; Karstens, F.; Katkov, I. I.; Kaur, M.; Kaur, P.; Keramidas, A.; Khein, L. A.; Kim, J. Y.; Kisielewska, D.; Kitamura, S.; Klanner, R.; Klein, U.; Koffeman, E.; Kollar, D.; Kooijman, P.; Korol, Ie.; Korzhavina, I. A.; Kota?ski, A.; Kötz, U.; Kowalski, H.; Kulinski, P.; Kuprash, O.; Kuze, M.; Lee, A.; Levchenko, B. B.; Levy, A.; Libov, V.; Limentani, S.; Ling, T. Y.; Lisovyi, M.; Lobodzinska, E.; Lohmann, W.; Löhr, B.; Lohrmann, E.; Loizides, J. H.; Long, K. R.; Longhin, A.; Lontkovskyi, D.; Lukina, O. Yu.; ?u?niak, P.; Maeda, J.; Magill, S.; Makarenko, I.; Malka, J.; Mankel, R.; Margotti, A.; Marini, G.; Martin, J. F.; Mastroberardino, A.; Matsumoto, T.; Mattingly, M. C. K.; Melzer-Pellmann, I.-A.; Miglioranzi, S.; Mohamad Idris, F.; Monaco, V.; Montanari, A.; Morris, J. D.; Musgrave, B.; Nagano, K.; Namsoo, T.; Nania, R.; Nicholass, D.; Nigro, A.; Ning, Y.; Noor, U.; Notz, D.; Nowak, R. J.; Nuncio-Quiroz, A. E.; Oh, B. Y.; Okazaki, N.; Oliver, K.; Olkiewicz, K.; Onishchuk, Yu.; Ota, O.; Papageorgiu, K.; Parenti, A.; Paul, E.; Pawlak, J. M.; Pawlik, B.; Pelfer, P. G.; Pellegrino, A.; Perlanski, W.; Perrey, H.; Piotrzkowski, K.; Plucinski, P.; Pokrovskiy, N. S.; Polini, A.; P Roskuryakov, A. S.; Przybycie?, M.; Raval, A.; Reeder, D. D.; Reisert, B.; Ren, Z.; Repond, J.; Ri, Y. D.; Robertson, A.; Roloff, P.; Ron, E.; Rubinsky, I.; Ruspa, M.; Sacchi, R.; Salii, A.; Samson, U.; Sartorelli, G.; Savin, A. A.; Saxon, D. H.; Schioppa, M.; Schlenstedt, S.; Schleper, P.; Schmidke, W. B.; Schneekloth, U.; Schönberg, V.; Schörner-Sadenius, T.; Schwartz, J.; Sciulli, F.; Shcheglova, L. M.; Shehzadi, R.; Shimizu, S.; Singh, I.; Skillicorn, I. O.; Slomi?ski, W.; Smith, W. H.; Sola, V.; Solano, A.; Son, D.; Sosnovtsev, V.; Spiridonov, A.; Stadie, H.; Stanco, L.; Stern, A.; Stewart, T. P.; Stifutkin, A.; Stopa, P.; Suchkov, S.; Susinno, G.; Suszycki, L.; Sztuk, J.; Szuba, D.; Szuba, J.; Tapper, A. D.; Tassi, E.; Terrón, J.; Theedt, T.; Tiecke, H.; Tokushuku, K.; Tomalak, O.; Tomaszewska, J.; Tsurugai, T.; Turcato, M.; Tymieniecka, T.; Uribe-Estrada, C.; Vázquez, M.; Verbytskyi, A.; Viazlo, O.; Vlasov, N. N.; Volynets, O.; Walczak, R.; Wan Abdullah, W. A. T.; Whitmore, J. J.; Whyte, J.; Wiggers, L.; Wing, M.; Wlasenko, M.; Wolf, G.; Wolfe, H.; Wrona, K.; Yagües-Molina, A. A.; Yamada, S.; Yamazaki, Y.; Yoshida, R.; Youngman, C.; ?arnecki, A. A.; Zawiejski, L.; Zenaiev, O.; Zeuner, W.; Zhautykov, B. O.; Zhmak, N.; Zhou, C.; Zichichi, A.; Zolko, M.; Zotkin, D. S.; Zulkapli, Z.

2010-11-01

169

A crossed-beam study of the reactive and unreactive scattering of Ar +( 2P 3/2) and Ar +( 2P 1/2) by N 2 at low energies  

NASA Astrophysics Data System (ADS)

The reactive and non-reactive scattering of state-selected Ar +( 2P 3/2 and Ar +( 2P 1/2) by N 2 have been investigated at center-of-mass collision energies of 0.78 and 1.54 eV using a crossed-beam apparatus. The percentage of Ar +( 2P 1/2) in the ion beam could be varied between about 1% and 33% by varying the operating conditions of a high-presure ion source. These ions were then mass selected, decelerated after mass analysis, and crossed at 90° by a He-seeded supersonic N 2 beam. Data obtained for the reactive channel confirm and expand previous data published by this laboratory and demonstrate that a transition from a direct mechanism generating primarily N +2 (X 2? +g, ? = 1) at both lower and higher energies and to a mechanism which populates all energetically accessible vibrational states of N +2 (X 2? +g) takes place in the collision energy range 0.8-1.5 eV. The non-reactive scattering of Ar + ( 2P 3/2) was forward peaked at both collision energies and showed vibrationally elastic and inelastic channels. In the backwards direction the quenching of Ar + ( 2P 1/2) to Ar + ( 2P 3/2) with simultaneous vibrational excitation of N 2( 1? +g) was clearly distinguishable from the non-reactively scattered Ar + ( 2P 3/2). Quite different scattering patterns are observed for Ar + ( 2P 3/2) and Ar + ( 2P 1/2).

Birkinshaw, Keith; Shukla, Anil; Howard, Stephen; Futrell, Jean H.

1987-04-01

170

Reactive phosphorus removal from aquaculture and poultry productions systems using polymeric hydrogels.  

PubMed

This work reports on the features of a sorption processes for the ultimate removal and recovery of reactive phosphorus from aquaculture and poultry production wastewater effluents. The sorbent used was a cross-linked polyamine (PAA-HCl) polymeric hydrogel. The PAA-HCl hydrogels were prepared by chemically cross-linking aqueous solutions of linear PAA-HCl chains with epichlorohydrin (EPI). The phosphorus binding capacity of the gels was measured in standard aqueous solutions as a function of ionic strength. Equilibrium PO4(3-), loadings of 100 mg anion/g gel were obtained. The regeneration ability of the gels was demonstrated by release of the bound phosphorus anions upon washing with 1-2 M NaOH solution, providing opportunities to recover and reuse the gel over multiple cycles. The ionic polyamine gels have been demonstrated to be appropriate materials for treating poultry and aquaculture wastewater effluents. Upon treatment phosphorus anion concentrations were reduced to levels suitable for discharge into natural surface waters. PMID:12564918

Kofinas, Peter; Kioussis, Dimitri R

2003-01-15

171

Mitochondrial respiratory supercomplex association limits production of reactive oxygen species from complex I.  

PubMed

Abstract Aims: The mitochondrial respiratory chain is recognized today to be arranged in supramolecular assemblies (supercomplexes). Besides conferring a kinetic advantage (substrate channeling) and being required for the assembly and stability of Complex I, indirect considerations support the view that supercomplexes may also prevent excessive formation of reactive oxygen species (ROS) from the respiratory chain. In the present study, we have directly addressed this issue by testing the ROS generation by Complex I in two experimental systems in which the supramolecular organization of the respiratory assemblies is impaired by: (i) treatment either of bovine heart mitochondria or liposome-reconstituted supercomplex I-III with dodecyl maltoside; (ii) reconstitution of Complexes I and III at high phospholipids to protein ratio. Results: The results of our investigation provide experimental evidence that the production of ROS is strongly increased in either model, supporting the view that disruption or prevention of the association between Complex I and Complex III by different means enhances the generation of superoxide from Complex I. Innovation: Dissociation of supercomplexes may link oxidative stress and energy failure in a vicious circle. Conclusion: Our findings support a central role of mitochondrial supramolecular structure in the development of the aging process and in the etiology and pathogenesis of most major chronic diseases. Antioxid. Redox Signal. 19, 1469-1480. PMID:23581604

Maranzana, Evelina; Barbero, Giovanna; Falasca, Anna Ida; Lenaz, Giorgio; Genova, Maria Luisa

2013-06-28

172

The alternative oxidase lowers mitochondrial reactive oxygen production in plant cells  

PubMed Central

Besides the cytochrome c pathway, plant mitochondria have an alternative respiratory pathway that is comprised of a single homodimeric protein, alternative oxidase (AOX). Transgenic cultured tobacco cells with altered levels of AOX were used to test the hypothesis that the alternative pathway in plant mitochondria functions as a mechanism to decrease the formation of reactive oxygen species (ROS) produced during respiratory electron transport. Using the ROS-sensitive probe 2?,7?-dichlorofluorescein diacetate, we found that antisense suppression of AOX resulted in cells with a significantly higher level of ROS compared with wild-type cells, whereas the overexpression of AOX resulted in cells with lower ROS abundance. Laser-scanning confocal microscopy showed that the difference in ROS abundance among wild-type and AOX transgenic cells was caused by changes in mitochondrial-specific ROS formation. Mitochondrial ROS production was exacerbated by the use of antimycin A, which inhibited normal cytochrome electron transport. In addition, cells overexpressing AOX were found to have consistently lower expression of genes encoding ROS-scavenging enzymes, including the superoxide dismutase genes SodA and SodB, as well as glutathione peroxidase. Also, the abundance of mRNAs encoding salicylic acid-binding catalase and a pathogenesis-related protein were significantly higher in cells deficient in AOX. These results are evidence that AOX plays a role in lowering mitochondrial ROS formation in plant cells.

Maxwell, Denis P.; Wang, Yong; McIntosh, Lee

1999-01-01

173

Reactivity of chlorine radical with submicron palmitic acid particles: kinetic measurements and products identification  

NASA Astrophysics Data System (ADS)

The heterogeneous reaction of Cl. radicals with sub-micron palmitic acid (PA) particles was studied in an aerosol flow tube in the presence or in the absence of O2. Fine particles were generated by homogeneous condensation of PA vapors and introduced in the reactor where chlorine atoms are produced by photolysis of Cl2 using UV lamps surrounding the reactor. The effective reactive uptake coefficient (?) has been determined from the rate loss of PA measured by GC/MS analysis of reacted particles as a function of the chlorine exposure. In the absence of O2, ? = 14 ± 5 indicates efficient secondary chemistry involving Cl2. GC/MS analyses have shown the formation of monochlorinated and polychlorinated compounds in the oxidized particles. Although, the PA particles are solid, the complete mass can be consumed. In the presence of oxygen, the reaction is still dominated by secondary chemistry but the propagation chain length is smaller than in the absence of O2 which leads to an uptake coefficient ? = 3 ± 1. In the particulate phase, oxocarboxylic acids and dicarboxylic acids are identified by GC/MS. Formation of alcohols and monocarboxylic acids are also suspected. All these results show that solid organic particles could be efficiently oxidized by gas-phase radicals not only on their surface, but also in bulk by mechanisms which are still unclear. Furthermore the identified reaction products are explained by a chemical mechanism showing the pathway of the formation of more functionalized products. They help to understand the aging of primary tropospheric aerosol containing fatty acids.

Mendez, M.; Ciuraru, R.; Gosselin, S.; Batut, S.; Visez, N.; Petitprez, D.

2013-06-01

174

Glutathione depletion and the production of reactive oxygen species in isolated hepatocyte suspensions.  

PubMed

Diethyl maleate (DEM) (5 mM) and ethyl methanesulfonate (EMS) (35 mM) treatments rapidly depleted cellular reduced glutathione (GSH) below detectable levels (1 nmol/10(6) cells), and induced lipid peroxidation and necrotic cell death in freshly isolated rat hepatocytes. In hepatocytes incubated with 2.5 mM DEM and 10 mM EMS, however, the complete depletion of cellular GSH observed was not sufficient to induce lipid peroxidation or cell death. Instead, DEM- and EMS-induced lipid peroxidation and cell death were dependent on increased reactive oxygen species (ROS) production as measured by increases in dichlorofluorescein fluorescence. The addition of antioxidants (vitamin E succinate and deferoxamine) prevented lipid peroxidation and cell death, suggesting that lipid peroxidation is involved in the sequence of events leading to necrotic cell death induced by DEM and EMS. To investigate the subcellular site of ROS generation, the cytochrome P450 inhibitor, SKF525A, was found to reduce EMS-induced lipid peroxidation but did not protect against the loss of cell viability, suggesting a mitochondrial origin for the toxic lipid peroxidation event. In agreement with this conclusion, mitochondrial electron transport inhibitors (rotenone, thenoyltrifluoroacetone and antimycin A) increased EMS-induced lipid peroxidation and cell death, while the mitochondrial uncoupler, carbonyl cyanide m-chlorophenylhydrazone, blocked EMS- and DEM-mediated ROS production and lipid peroxidation. Furthermore, EMS treatment resulted in the significant loss of mitochondrial alpha-tocopherol shortly after its addition, and this loss preceded losses in cellular alpha-tocopherol levels. Treatment of hepatocytes with cyclosporin A, a mitochondrial permeability transition inhibitor, oxypurinol, a xanthine oxidase inhibitor, or BAPTA-AM, a calcium chelator, provided no protection against EMS-induced cell death or lipid peroxidation. Our results indicate that DEM and EMS induce cell death by a similar mechanism, which is dependent on the induction of ROS production and lipid peroxidation, and mitochondria are the major source for this toxic ROS generation. Cellular GSH depletion in itself does not appear to be responsible for the large increases in ROS production and lipid peroxidation observed. PMID:10967318

Tirmenstein, M A; Nicholls-Grzemski, F A; Zhang, J G; Fariss, M W

2000-07-14

175

HIV antiretroviral drug combination induces endothelial mitochondrial dysfunction and reactive oxygen species production, but not apoptosis  

SciTech Connect

Numerous reports now indicate that HIV patients administered long-term antiretroviral therapy (ART) are at a greater risk for developing cardiovascular diseases. Endothelial dysfunction is an initiating event in atherogenesis and may contribute to HIV-associated atherosclerosis. We previously reported that ART induces direct endothelial dysfunction in rodents. In vitro treatment of human umbilical vein endothelial cells (HUVEC) with ART indicated endothelial mitochondrial dysfunction and a significant increase in the production of reactive oxygen species (ROS). In this study, we determined whether ART-induced endothelial dysfunction is mediated via mitochondria-derived ROS and whether this mitochondrial injury culminates in endothelial cell apoptosis. Two major components of ART combination therapy, a nucleoside reverse transcriptase inhibitor and a protease inhibitor, were tested, using AZT and indinavir as representatives for each. Microscopy utilizing fluorescent indicators of ROS and mitochondria demonstrated the mitochondrial localization of ART-induced ROS. MnTBAP, a cell-permeable metalloporphyrin antioxidant, abolished ART-induced ROS production. As a final step in confirming the mitochondrial origin of the ART-induced ROS, HUVEC were transduced with a cytosolic- compared to a mitochondria-targeted catalase. Transduction with the mitochondria-targeted catalase was more effective than cytoplasmic catalase in inhibiting the ROS and 8-isoprostane (8-iso-PGF{sub 2{alpha}}) produced after treatment with either AZT or indinavir. However, both mitochondrial and cytoplasmic catalase attenuated ROS and 8-iso-PGF{sub 2{alpha}} production induced by the combination treatment, suggesting that in this case, the formation of cytoplasmic ROS may also occur, and thus, that the mechanism of toxicity in the combination treatment group may be different compared to treatment with AZT or indinavir alone. Finally, to determine whether ART-induced mitochondrial dysfunction and ROS production culminate in apoptosis, we performed the terminal deoxynucleotidyl transferase biotin-dUTP nick end labeling (TUNEL), annexin V and 4',6-diamidino-2-phenylindole (DAPI) staining, and caspase-3 activity assays. However, none of these assays showed appreciable levels of ART-induced apoptosis. Our studies thus suggest that in endothelial cells, ART induces mitochondrial dysfunction with a concomitant increase in mitochondria-derived ROS. This compromised mitochondrial function may be one important factor culminating in endothelial dysfunction, without inducing an increase in apoptosis.

Jiang Bo; Hebert, Valeria Y. [Department of Pharmacology, Toxicology and Neuroscience, Louisiana State University Health Sciences Center, 1501 Kings Highway, Shreveport, LA 71103 (United States); Li, Yuchi [Cardiopulmonary Research Institute, Winthrop University Hospital, State University of New York at Stony Brook School of Medicine, Mineola, NY 11501 (United States); Mathis, J. Michael [Department of Cellular Biology and Anatomy, Louisiana State University Health Sciences Center, 1501 Kings Highway, Shreveport, LA 71103 (United States); Alexander, J. Steven [Department of Molecular and Cellular Physiology, Louisiana State University Health Sciences Center, 1501 Kings Highway, Shreveport, LA 71103 (United States); Dugas, Tammy R. [Department of Pharmacology, Toxicology and Neuroscience, Louisiana State University Health Sciences Center, 1501 Kings Highway, Shreveport, LA 71103 (United States)], E-mail: tdugas@lsuhsc.edu

2007-10-01

176

Effects of pectic polysaccharides isolated from leek on the production of reactive oxygen and nitrogen species by phagocytes.  

PubMed

Abstract The current survey investigates the effect of four polysaccharides isolated from fresh leek or alcohol insoluble substances (AIS) of leek on the production of reactive oxygen species (ROS) and reactive nitrogen species (RNS) from phagocytes. The ability of the polysaccharides to activate serum complement was also investigated. Despite the lack of antioxidant activity, the pectic polysaccharides significantly decreased the production of ROS by human neutrophils. Polysaccharides isolated from AIS markedly activated RAW 264.7 macrophages for RNS production in a concentration-dependent manner. The Western blot analysis revealed that this effect was due to the stimulation of the inducible nitric oxide synthase protein expression of macrophages. The polysaccharides extracted from AIS with water showed the ability to fix serum complement, especially through the alternative pathway. It was found that the polysaccharide that has the highest complement-fixing effect is characterized by the highest content of uronic acids and the highest molecular weight. PMID:23905651

Nikolova, Mariana; Ambrozova, Gabriela; Kratchanova, Maria; Denev, Petko; Kussovski, Veselin; Ciz, Milan; Lojek, Antonin

2013-08-01

177

Impact of atmospheric aerosol light scattering and absorption on terrestrial net primary productivity  

NASA Astrophysics Data System (ADS)

Scattering and absorption of sunlight by anthropogenic aerosols reduce the photosynthetically active radiation (PAR) incident upon the Earth's surface, but increase the fraction of the PAR that is diffuse. These alterations to irradiance may elicit conflicting responses in terrestrial plants: photosynthesis and net primary productivity (NPP) are slowed by reductions in total PAR, but enhanced by increases in diffuse PAR. In this paper, we use two canopy photosynthesis models to estimate the net effect of aerosols on carbon assimilation by green plants during summertime at midlatitudes. The model calculations indicate that the net effect of PAR scattering and absorption by atmospheric aerosols on NPP can be positive, neutral, or negative. Two parameters that strongly influence the net effect are the aerosol optical depth (integral of light extinction with height) and the cloud cover. On cloudless days NPP peaks under moderately thick aerosol loadings. On overcast days, aerosols slow NPP. The implications of these results for various regions of the globe and possible directions for future studies on the effect of aerosols on plant growth are discussed.

Cohan, Daniel S.; Xu, Jin; Greenwald, Roby; Bergin, Michael H.; Chameides, William L.

2002-12-01

178

Properties of inclusive hadron production in deep inelastic scattering on heavy nuclei at low x  

NASA Astrophysics Data System (ADS)

We present a comprehensive study of inclusive hadron production in deep inelastic scattering (DIS) at low x. Properties of the hadron spectrum are different in different kinematic regions formed by three relevant momentum scales: photon virtuality Q2, hadron transverse momentum kT and the saturation momentum Qs(x). We investigate each kinematic region and derive the corresponding asymptotic formulas for the cross section at the leading logarithmic order. We also analyze the next-to-leading-order corrections to the Balitski?-Fadin-Kuraev-Lipatov kernel that are responsible for the momentum conservation. In particular, we establish the asymptotic behavior of the forward elastic dipole-nucleus scattering amplitude at high energies deeply in the saturation regime and a modification of the pomeron intercept. We study the nuclear effect on the inclusive cross section using the nuclear modification factor and its logarithmic derivative. We argue that the later is proportional to the difference between the anomalous dimension of the gluon distribution in nucleus and in proton and thus is a direct measure of the coherence effects. To augment our arguments and present quantitative results we performed numerical calculations in the kinematic region that may be accessible by the future DIS experiments.

Tuchin, Kirill; Wu, Dajing

2012-06-01

179

Tumour necrosis factor enhances the asbestos-induced production of reactive oxygen metabolites by human polymorphonuclear leucocytes (PMN).  

PubMed Central

We studied the effect of recombinant tumour necrosis factor-alpha (TNF-alpha) on the production of reactive oxygen metabolites (ROM) by human PMN exposed in vitro to chrysotile and crocidolite asbestos fibres, quartz dusts and opsonized zymosan. TNF caused a significant increase in ROM release by PMN, and significantly and dose-dependently amplified the ROM production induced by asbestos fibres. The amplification of ROM production by TNF can be of crucial importance in the process of lung inflammation and fibrogenesis in pneumoconioses.

Klockars, M; Savolainen, H

1992-01-01

180

Multijet production at low x in deep inelastic scattering at HERA  

NASA Astrophysics Data System (ADS)

Inclusive dijet and trijet production in deep inelastic ep scattering has been measured for 10

ZEUS Collaboration; Chekanov, S.; Derrick, M.; Magill, S.; Musgrave, B.; Nicholass, D.; Repond, J.; Yoshida, R.; Mattingly, M. C. K.; Jechow, M.; Pavel, N.; Yagües Molina, A. G.; Antonelli, S.; Antonioli, P.; Bari, G.; Basile, M.; Bellagamba, L.; Bindi, M.; Boscherini, D.; Bruni, A.; Bruni, G.; Cifarelli, L.; Cindolo, F.; Contin, A.; Corradi, M.; de Pasquale, S.; Iacobucci, G.; Margotti, A.; Nania, R.; Polini, A.; Sartorelli, G.; Zichichi, A.; Bartsch, D.; Brock, I.; Goers, S.; Hartmann, H.; Hilger, E.; Jakob, H.-P.; Jüngst, M.; Kind, O. M.; Nuncio-Quiroz, A. E.; Paul, E.; Renner, R.; Samson, U.; Schönberg, V.; Shehzadi, R.; Wlasenko, M.; Brook, N. H.; Heath, G. P.; Morris, J. D.; Namsoo, T.; Capua, M.; Fazio, S.; Mastroberardino, A.; Schioppa, M.; Susinno, G.; Tassi, E.; Kim, J. Y.; Ma, K. J.; Ibrahim, Z. A.; Kamaluddin, B.; Wan Abdullah, W. A. T.; Ning, Y.; Ren, Z.; Sciulli, F.; Chwastowski, J.; Eskreys, A.; Figiel, J.; Galas, A.; Gil, M.; Olkiewicz, K.; Stopa, P.; Zawiejski, L.; Adamczyk, L.; Bo?d, T.; Grabowska-Bo?d, I.; Kisielewska, D.; ?ukasik, J.; Przybycie?, M.; Suszycki, L.; Kota?ski, A.; S?omi?ski, W.; Adler, V.; Behrens, U.; Bloch, I.; Blohm, C.; Bonato, A.; Borras, K.; Ciesielski, R.; Coppola, N.; Dossanov, A.; Drugakov, V.; Fourletova, J.; Geiser, A.; Gladkov, D.; Göttlicher, P.; Grebenyuk, J.; Gregor, I.; Haas, T.; Hain, W.; Horn, C.; Hüttmann, A.; Kahle, B.; Katkov, I. I.; Klein, U.; Kötz, U.; Kowalski, H.; Lobodzinska, E.; Löhr, B.; Mankel, R.; Melzer-Pellmann, I.-A.; Miglioranzi, S.; Montanari, A.; Notz, D.; Rinaldi, L.; Roloff, P.; Rubinsky, I.; Santamarta, R.; Schneekloth, U.; Spiridonov, A.; Stadie, H.; Szuba, D.; Szuba, J.; Theedt, T.; Wolf, G.; Wrona, K.; Youngman, C.; Zeuner, W.; Lohmann, W.; Schlenstedt, S.; Barbagli, G.; Gallo, E.; Pelfer, P. G.; Bamberger, A.; Dobur, D.; Karstens, F.; Vlasov, N. N.; Bussey, P. J.; Doyle, A. T.; Dunne, W.; Ferrando, J.; Forrest, M.; Saxon, D. H.; Skillicorn, I. O.; Gialas, I.; Papageorgiu, K.; Gosau, T.; Holm, U.; Klanner, R.; Lohrmann, E.; Salehi, H.; Schleper, P.; Schörner-Sadenius, T.; Sztuk, J.; Wichmann, K.; Wick, K.; Foudas, C.; Fry, C.; Long, K. R.; Tapper, A. D.; Kataoka, M.; Matsumoto, T.; Nagano, K.; Tokushuku, K.; Yamada, S.; Yamazaki, Y.; Barakbaev, A. N.; Boos, E. G.; Pokrovskiy, N. S.; Zhautykov, B. O.; Aushev, V.; Son, D.; de Favereau, J.; Piotrzkowski, K.; Barreiro, F.; Glasman, C.; Jimenez, M.; Labarga, L.; Del Peso, J.; Ron, E.; Soares, M.; Terrón, J.; Zambrana, M.; Corriveau, F.; Liu, C.; Walsh, R.; Zhou, C.; Tsurugai, T.; Antonov, A.; Dolgoshein, B. A.; Sosnovtsev, V.; Stifutkin, A.; Suchkov, S.; Dementiev, R. K.; Ermolov, P. F.; Gladilin, L. K.; Khein, L. A.; Korzhavina, I. A.; Kuzmin, V. A.; Levchenko, B. B.; Lukina, O. Yu.; Proskuryakov, A. S.; Shcheglova, L. M.; Zotkin, D. S.; Zotkin, S. A.; Abt, I.; Büttner, C.; Caldwell, A.; Kollar, D.; Schmidke, W. B.; Sutiak, J.; Grigorescu, G.; Keramidas, A.; Koffeman, E.; Kooijman, P.; Pellegrino, A.; Tiecke, H.; Vázquez, M.; Wiggers, L.; Brümmer, N.; Bylsma, B.; Durkin, L. S.; Lee, A.; Ling, T. Y.; Allfrey, P. D.; Bell, M. A.; Cooper-Sarkar, A. M.; Cottrell, A.; Devenish, R. C. E.; Foster, B.; Korcsak-Gorzo, K.; Patel, S.; Roberfroid, V.; Robertson, A.; Straub, P. B.; Uribe-Estrada, C.; Walczak, R.; Bellan, P.; Bertolin, A.; Brugnera, R.; Carlin, R.; Dal Corso, F.; Dusini, S.; Garfagnini, A.; Limentani, S.; Longhin, A.; Stanco, L.; Turcato, M.; Oh, B. Y.; Raval, A.; Ukleja, J.; Whitmore, J. J.; Iga, Y.; D'Agostini, G.; Marini, G.; Nigro, A.; Cole, J. E.; Hart, J. C.; Abramowicz, H.; Gabareen, A.; Ingbir, R.; Kananov, S.; Levy, A.; Kuze, M.; Maeda, J.; Hori, R.; Kagawa, S.; Okazaki, N.; Shimizu, S.; Tawara, T.; Hamatsu, R.; Kaji, H.; Kitamura, S.; Ota, O.; Ri, Y. D.; Ferrero, M. I.; Monaco, V.; Sacchi, R.; Solano, A.; Arneodo, M.; Ruspa, M.; Fourletov, S.; Martin, J. F.; Boutle, S. K.; Butterworth, J. M.; Gwenlan, C.; Jones, T. W.; Loizides, J. H.; Sutton, M. R.; Wing, M.; Brzozowska, B.; Ciborowski, J.; Grzelak, G.; Kulinski, P.; ?u?niak, P.; Malka, J.; Nowak, R. J.; Pawlak, J. M.; Tymieniecka, T.; Ukleja, A.; ?arnecki, A. F.; Adamus, M.; Plucinski, P.; Eisenberg, Y.; Giller, I.; Hochman, D.; Karshon, U.; Rosin, M.; Brownson, E.; Danielson, T.; Everett, A.; Kçira, D.; Reeder, D. D.; Ryan, P.; Savin, A. A.; Smith, W. H.; Wolfe, H.; Bhadra, S.; Catterall, C. D.; Cui, Y.; Hartner, G.; Menary, S.; Noor, U.; Standage, J.; Whyte, J.

2007-12-01

181

Muon production in low-energy electron-nucleon and electron-nucleus scattering  

SciTech Connect

Recently, muon production in electron-proton scattering has been suggested as a possible candidate reaction for the identification of lepton-flavor violation due to physics beyond the standard model. Here we point out that the standard-model processes e{sup -}p{yields}{mu}{sup -}p{nu}{sub {mu}}{nu}{sub e} and e{sup -}p{yields}e{sup -}n{mu}{sup +}{nu}{sub {mu}} can cloud potential beyond-the-standard-model signals in ep collisions. We find that standard-model ep{yields}{mu}X cross sections exceed those from lepton-flavor-violating operators by several orders of magnitude. We also discuss the possibility of using a nuclear target to enhance the ep{yields}{mu}X signal.

Jaikumar, Prashanth [Department of Physics and Astronomy, Ohio University, Athens, Ohio 45701 (United States); Institute of Mathematical Sciences, C. I. T. Campus, Taramani, Chennai 600113 (India); Phillips, Daniel R.; Platter, Lucas; Prakash, Madappa [Department of Physics and Astronomy, Ohio University, Athens, Ohio 45701 (United States)

2007-12-01

182

Production of heavy quarks in deep-inelastic lepton-hadron scattering  

NASA Astrophysics Data System (ADS)

We will give a review of the computation of exact next-to-leading order corrections to heavy quark production in deep inelastic lepton-hadron scattering and discuss the progress made in this field over the past ten years. In this approach, hereafter called EXACT, where the heavy quark mass is taken to be of the same order of magnitude as the other large scales in the process, one can apply perturbation theory in all orders of the strong coupling constant ?s. The results are compared with another approach, called the variable flavor number scheme (VFNS), where the heavy quark is also treated as a massless quark. It turns out that the differences between the two approaches are very small provided both of them are carried out up to next-to-next-to-leading order. .

van Neerven, W. L.

2001-11-01

183

Measurement of D ± production in deep inelastic ep scattering with the ZEUS detector at HERA  

NASA Astrophysics Data System (ADS)

Charm production in deep inelastic ep scattering was measured with the ZEUS detector using an integrated luminosity of 354 pb-1. Charm quarks were identified by reconstructing D ± mesons in the D ± ? K ??±?± decay channel. Lifetime information was used to reduce combinatorial background substantially. Differential cross sections were measured in the kinematic region 5 < Q 2 < 1000 GeV2, 0 .02 < y < 0 .7, 1 .5 < p T ( D ±) < 15 GeV and | ?( D ±)| < 1 .6, where Q 2 is the photon virtuality, y is the inelasticity, and p T ( D ±) and ?( D ±) are the transverse momentum and the pseudorapidity of the D ± meson, respectively. Next-to-leading-order QCD predictions are compared to the data. The charm contribution, F_2^{{coverline{c}}} , to the proton structure-function F 2 was extracted.

Abramowicz, H.; Abt, I.; Adamczyk, L.; Adamus, M.; Aggarwal, R.; Antonelli, S.; Antonioli, P.; Antonov, A.; Arneodo, M.; Arslan, O.; Aushev, V.; Aushev, Y.; Bachynska, O.; Bamberger, A.; Barakbaev, A. N.; Barbagli, G.; Bari, G.; Barreiro, F.; Bartosik, N.; Bartsch, D.; Basile, M.; Behnke, O.; Behr, J.; Behrens, U.; Bellagamba, L.; Bertolin, A.; Bhadra, S.; Bindi, M.; Blohm, C.; Bokhonov, V.; Bold, T.; Boos, E. G.; Borras, K.; Boscherini, D.; Bot, D.; Brock, I.; Brownson, E.; Brugnera, R.; Brümmer, N.; Bruni, A.; Bruni, G.; Brzozowska, B.; Bussey, P. J.; Bylsma, B.; Caldwell, A.; Capua, M.; Carlin, R.; Catterall, C. D.; Chekanov, S.; Chwastowski, J.; Ciborowski, J.; Ciesielski, R.; Cifarelli, L.; Cindolo, F.; Contin, A.; Cooper-Sarkar, A. M.; Coppola, N.; Corradi, M.; Corriveau, F.; Costa, M.; D'Agostini, G.; Corso, F. Dal; del Peso, J.; Dementiev, R. K.; De Pasquale, S.; Derrick, M.; Devenish, R. C. E.; Dobur, D.; Dolgoshein, B. A.; Dolinska, G.; Doyle, A. T.; Drugakov, V.; Durkin, L. S.; Dusini, S.; Eisenberg, Y.; Ermolov, P. F.; Eskreys, A.; Fang, S.; Fazio, S.; Ferrando, J.; Ferrero, M. I.; Figiel, J.; Foster, B.; Gach, G.; Galas, A.; Gallo, E.; Garfagnini, A.; Geiser, A.; Gialas, I.; Gizhko, A.; Gladilin, L. K.; Gladkov, D.; Glasman, C.; Gogota, O.; Golubkov, Yu. A.; Göttlicher, P.; Grabowska-Bold, I.; Grebenyuk, J.; Gregor, I.; Grigorescu, G.; Grzelak, G.; Gueta, O.; Guzik, M.; Gwenlan, C.; Haas, T.; Hain, W.; Hamatsu, R.; Hart, J. C.; Hartmann, H.; Hartner, G.; Hilger, E.; Hochman, D.; Hori, R.; Hüttmann, A.; Ibrahim, Z. A.; Iga, Y.; Ingbir, R.; Ishitsuka, M.; Iudin, A.; Jakob, H.-P.; Januschek, F.; Jones, T. W.; Jüngst, M.; Kadenko, I.; Kahle, B.; Kananov, S.; Kanno, T.; Karshon, U.; Karstens, F.; Katkov, I. I.; Kaur, M.; Kaur, P.; Keramidas, A.; Khein, L. A.; Kim, J. Y.; Kisielewska, D.; Kitamura, S.; Klanner, R.; Klein, U.; Koffeman, E.; Kondrashova, N.; Kononenko, O.; Kooijman, P.; Korol, Ie.; Korzhavina, I. A.; Kotanski, A.; Kötz, U.; Kovalchuk, N.; Kowalski, H.; Kuprash, O.; Kuze, M.; Lee, A.; Levchenko, B. B.; Levy, A.; Libov, V.; Limentani, S.; Ling, T. Y.; Lisovyi, M.; Lobodzinska, E.; Lohmann, W.; Löhr, B.; Lohrmann, E.; Long, K. R.; Longhin, A.; Lontkovskyi, D.; Lukina, O. Yu.; Maeda, J.; Magill, S.; Makarenko, I.; Malka, J.; Mankel, R.; Margotti, A.; Marini, G.; Martin, J. F.; Mastroberardino, A.; Mattingly, M. C. K.; Melzer-Pellmann, I.-A.; Mergelmeyer, S.; Miglioranzi, S.; Idris, F. Mohamad; Monaco, V.; Montanari, A.; Morris, J. D.; Mujkic, K.; Musgrave, B.; Nagano, K.; Namsoo, T.; Nania, R.; Nigro, A.; Ning, Y.; Nobe, T.; Notz, D.; Nowak, R. J.; Nuncio-Quiroz, A. E.; Oh, B. Y.; Okazaki, N.; Olkiewicz, K.; Onishchuk, Yu.; Papageorgiu, K.; Parenti, A.; Paul, E.; Pawlak, J. M.; Pawlik, B.; Pelfer, P. G.; Pellegrino, A.; Perlanski, W.; Perrey, H.; Piotrzkowski, K.; Plucinski, P.; Pokrovskiy, N. S.; Polini, A.; Proskuryakov, A. S.; Przybycien, M.; Raval, A.; Reeder, D. D.; Reisert, B.; Ren, Z.; Repond, J.; Ri, Y. D.; Robertson, A.; Roloff, P.; Rubinsky, I.; Ruspa, M.; Sacchi, R.; Samson, U.; Sartorelli, G.; Savin, A. A.; Saxon, D. H.; Schioppa, M.; Schlenstedt, S.; Schleper, P.; Schmidke, W. B.; Schneekloth, U.; Schönberg, V.; Schörner-Sadenius, T.; Schwartz, J.; Sciulli, F.; Shcheglova, L. M.; Shehzadi, R.; Shimizu, S.; Singh, I.; Skillicorn, I. O.; Slominski, W.; Smith, W. H.; Sola, V.; Solano, A.; Son, D.; Sosnovtsev, V.; Spiridonov, A.; Stadie, H.; Stanco, L.; Stefaniuk, N.; Stern, A.; Stewart, T. P.; Stifutkin, A.; Stopa, P.; Suchkov, S.; Susinno, G.; Suszycki, L.; Sztuk-Dambietz, J.; Szuba, D.; Szuba, J.; Tapper, A. D.; Tassi, E.; Terrón, J.; Theedt, T.; Tiecke, H.; Tokushuku, K.; Tomaszewska, J.; Trofymov, A.; Trusov, V.; Tsurugai, T.; Turcato, M.; Turkot, O.; Tymieniecka, T.; Vázquez, M.; Verbytskyi, A.; Viazlo, O.; Vlasov, N. N.; Walczak, R.; Abdullah, W. A. T. Wan; Whitmore, J. J.; Wichmann, K.; Wiggers, L.; Wing, M.; Wlasenko, M.; Wolf, G.; Wolfe, H.; Wrona, K.; Yagües-Molina, A. G.; Yamada, S.; Yamazaki, Y.; Yoshida, R.; Youngman, C.; Zakharchuk, N.; ?arnecki, A. F.; Zawiejski, L.; Zenaiev, O.; Zeuner, W.; Zhautykov, B. O.; Zhmak, N.; Zichichi, A.; Zolkapli, Z.; Zotkin, D. S.

2013-05-01

184

Reggeometry of Deeply Virtual Compton Scattering and Exclusive Vector Meson Production at HERA  

NASA Astrophysics Data System (ADS)

A Reggeometric (Regge+Geometry) model, based on the observed proportionality between the forward slope of the differential cross section and the interaction radius, the latter depending on virtuality Q2 of the incoming virtual photon and on the mass M 2 of the produced particle, is constructed. The objective of this study is the dependence of the Regge-pole amplitude on the virtuality Q2 and masses of the external particles, which remains an open problem for the theory. The present analysis is based on the HERA data on Deeply Virtual Compton Scattering (DVCS) and exclusive diffractive Vector Meson Production (VMP). We treat each class of reactions separately, anticipating a further study that will include both a soft and a hard component of the unique pomeron.

Fazio, S.; Fiore, R.; Lavorini, A.; Jenkovszky, L.; Salii, A.

185

Incoherent diffractive J/{Psi} production in high-energy nuclear deep-inelastic scattering  

SciTech Connect

We compute cross sections for incoherent diffractive J/{Psi} production in lepton-nucleus deep-inelastic scattering (DIS). The cross section is proportional to A in the dilute limit and to A{sup 1/3} in the black disk limit, with a large nuclear suppression due to saturation effects. The t dependence of the cross section, if it can be measured accurately enough, is sensitive to the impact parameter profile of the gluons in the nucleus and their fluctuations, a quantity that determines the initial conditions of a relativistic heavy-ion collision. The nuclear suppression in incoherent diffraction shows how the transverse spatial distribution of the gluons in the nucleus gradually becomes smoother at high energy. Since the values of the momentum transfer |t| involved are relatively large, this process should be easier to measure in future nuclear DIS experiments than coherent diffraction.

Lappi, T. [Department of Physics, P.O. Box 35, FI-40014 University of Jyvaeskylae (Finland); Helsinki Institute of Physics, P.O. Box 64, FI-00014 University of Helsinki (Finland); Maentysaari, H. [Department of Physics, P.O. Box 35, FI-40014 University of Jyvaeskylae (Finland)

2011-06-15

186

Orally absorbed reactive glycation products (glycotoxins): An environmental risk factor in diabetic nephropathy  

PubMed Central

Endogenous advanced glycation endproducts (AGEs) include chemically crosslinking species (glycotoxins) that contribute to the vascular and renal complications of diabetes mellitus (DM). Renal excretion of the catabolic products of endogenous AGEs is impaired in patients with diabetic or nondiabetic kidney disease (KD). The aim of this study was to examine the oral absorption and renal clearance kinetics of food AGEs in DM with KD and whether circulating diet-derived AGEs contain active glycotoxins. Thirty-eight diabetics (DM) with or without KD and five healthy subjects (NL) received a single meal of egg white (56 g protein), cooked with (AGE-diet) or without fructose (100 g) (CL-diet). Serum and urine samples, collected for 48 hr, were monitored for AGE immunoreactivity by ELISA and for AGE-specific crosslinking reactivity, based on complex formation with 125I-labeled fibronectin. The AGE-diet, but not the CL-diet, produced distinct elevations in serum AGE levels in direct proportion to amount ingested (r = 0.8, P < 0.05): the area under the curve for serum (?10% of ingested AGE) correlated directly with severity of KD; renal excretion of dietary AGE, although normally incomplete (only ?30% of amount absorbed), in DM it correlated inversely with degree of albuminuria, and directly with creatinine clearance (r = 0.8, P < 0.05), reduced to <5% in DM with renal failure. Post-AGE-meal serum exhibited increased AGE-crosslinking activity (two times above baseline serum AGE, three times above negative control), which was inhibited by aminoguanidine. In conclusion, (i) the renal excretion of orally absorbed AGEs is markedly suppressed in diabetic nephropathy patients, (ii) daily influx of dietary AGEs includes glycotoxins that may constitute an added chronic risk for renal-vascular injury in DM, and (iii) dietary restriction of AGE food intake may greatly reduce the burden of AGEs in diabetic patients and possibly improve prognosis.

Koschinsky, Theodore; He, Ci-Jiang; Mitsuhashi, Tomoko; Bucala, Richard; Liu, Cecilia; Buenting, Christina; Heitmann, Kirsten; Vlassara, Helen

1997-01-01

187

GABA shunt mediates thermotolerance in Saccharomyces cerevisiae by reducing reactive oxygen production.  

PubMed

The GABA shunt pathway involves three enzymes, glutamate decarboxylase (GAD), GABA aminotransferase (GAT) and succinate semialdehyde dehydrogenase (SSADH). These enzymes act in concert to convert glutamate (?-ketoglutarate) to succinate. Deletion mutations in each of these genes in Saccharomyces cerevisiae resulted in growth defects at 45°C. Double and triple mutation constructs were compared for thermotolerance with the wild-type and single mutant strains. Although wild-type and all mutant strains were highly susceptible to brief heat stress at 50°C, a non-lethal 30 min at 40°C temperature pretreatment induced tolerance of the wild-type and all of the mutants to 50°C. The mutant strains collectively exhibited similar susceptibility at 45°C to the induced 50°C treatments. Intracellular reactive oxygen intermediate (ROI) accumulation was measured in wild-type and each of the mutant strains. ROI accumulation in each of the mutants and in various stress conditions was correlated to heat susceptibility of the mutant strains. The addition of ROI scavenger N-tert-butyl-?-phenylnitrone (PBN) enhanced survival of the mutants and strongly inhibited the accumulation of ROI, but did not have significant effect on the wild-type. Measurement of intracellular GABA, glutamate and ?-ketoglutarate during lethal heat exposure at 45°C showed higher levels of accumulation of GABA and ?-ketoglutarate in the uga1 and uga2 mutants, while glutamate accumulated at higher level in the gad1 mutant. These results suggest that the GABA shunt pathway plays a crucial role in protecting yeast cells from heat damage by restricting ROI production involving the flux of carbon from ?-ketoglutarate to succinate during heat stress. PMID:23447388

Cao, Juxiang; Barbosa, Jose M; Singh, Narendra K; Locy, Robert D

2013-04-05

188

Reactivity of whole coals, selected pure maceral fractions, and cleaned coal products  

SciTech Connect

The overall objective of this project was to determine the chemical reactivity properties of pure single coal maceral fractions in order to predict the combustion behavior of various whole coals of different maceral compositions and rank. The results to data of this study clearly support the following list of important conclusions: Maceral interactions occur during combustion profile tests; Combustion profile temperatures and parameters are rank related but not all coals show the same rank relationships; Pure macerals more clearly define the rank relationships; Vitrinite and liptinite behavior is more predictable than inertinite behavior; Combustion profile temperatures vary as a function of whole coal sample density; Physical cleaning has positive or little effect on combustion profile behavior; If SCE is to be used to prepare combustion feedstocks, then deep physical cleaning is recommended to enhance desulfurization and combustion properties; Combustion profiles can be modeled as apparent first order reactions; Activation energy is independent of rank but not of maceral composition or rank type (i.e. rank band); Combustion curves can be normalized and fitted to a polynomial-log equation; Reactivity studies show that both whole coal and maceral concentrate reactivities decrease with increasing rank; Whole coal reactivities are not a weighted average of the maceral reactivities from that coal; Demineralized whole coals show a greater variation in reactivity than do untreated whole coal samples. 50 refs., 6 figs.

Crelling, J.C. (Southern Illinois Univ., Carbondale, IL (USA). Dept. of Geology); Hippo, E.J. (Southern Illinois Univ., Carbondale, IL (USA). Dept. of Mechanical Engineering and Energy Processes)

1991-01-01

189

Decreased Reactive Oxygen Species Production in Cells with Mitochondrial Haplogroups Associated with Longevity  

PubMed Central

Mitochondrial DNA (mtDNA) is highly polymorphic, and its variations in humans may contribute to individual differences in function. Zhang and colleagues found a strikingly higher frequency of a C150T transition in the D-loop of mtDNA from centenarians and twins of an Italian population, and also demonstrated that this base substitution causes a remodeling of the mtDNA 151 replication origin in human leukocytes and fibroblasts [1]. The C150T transition is a polymorphism associated with several haplogroups. To determine whether haplogroups that carry the C150T transition display any phenotype that may be advantageous for longevity, we analyzed cybrids carrying or not the C150T transition. These cybrids were obtained by fusing cytoplasts derived from human fibroblasts with human mtDNA-less cells (?0 cells). We chose for cybrid construction and analysis haplogroup-matched pairs of fibroblast strains containing or not the C150T transition. In particular, we used, as one pair of mtDNA donors, a fibroblast strain of the U3a haplogroup, carrying the C150T transition and a strain of the U-K2 haplogroup, without the C150T transition, and as another pair, fibroblasts of the J2b haplogroup, carrying the C150T transition and of the J1c haplogroup, without the C150T transition. We have found no association of respiratory capacity, mtDNA level, mitochondrial gene expression level, or growth rate with the presence of the C150T transition. However, we have found that the cybrids with haplogroups that include the C150T transition have in common a lower reactive oxygen species (ROS) production rate than the haplogroup-matched cybrids without that transition. Thus, the lower ROS production rate may be a factor in the increased longevity associated with the U and the J2 haplogroups. Of further interest, we found that cybrids with the U3a haplogroup exhibited a higher respiration rate than the other cybrids examined.

Chen, Ai; Raule, Nicola; Chomyn, Anne

2012-01-01

190

Decreased reactive oxygen species production in cells with mitochondrial haplogroups associated with longevity.  

PubMed

Mitochondrial DNA (mtDNA) is highly polymorphic, and its variations in humans may contribute to individual differences in function. Zhang and colleagues found a strikingly higher frequency of a C150T transition in the D-loop of mtDNA from centenarians and twins of an Italian population, and also demonstrated that this base substitution causes a remodeling of the mtDNA 151 replication origin in human leukocytes and fibroblasts [1]. The C150T transition is a polymorphism associated with several haplogroups. To determine whether haplogroups that carry the C150T transition display any phenotype that may be advantageous for longevity, we analyzed cybrids carrying or not the C150T transition. These cybrids were obtained by fusing cytoplasts derived from human fibroblasts with human mtDNA-less cells (?(0) cells). We chose for cybrid construction and analysis haplogroup-matched pairs of fibroblast strains containing or not the C150T transition. In particular, we used, as one pair of mtDNA donors, a fibroblast strain of the U3a haplogroup, carrying the C150T transition and a strain of the U-K2 haplogroup, without the C150T transition, and as another pair, fibroblasts of the J2b haplogroup, carrying the C150T transition and of the J1c haplogroup, without the C150T transition. We have found no association of respiratory capacity, mtDNA level, mitochondrial gene expression level, or growth rate with the presence of the C150T transition. However, we have found that the cybrids with haplogroups that include the C150T transition have in common a lower reactive oxygen species (ROS) production rate than the haplogroup-matched cybrids without that transition. Thus, the lower ROS production rate may be a factor in the increased longevity associated with the U and the J2 haplogroups. Of further interest, we found that cybrids with the U3a haplogroup exhibited a higher respiration rate than the other cybrids examined. PMID:23144696

Chen, Ai; Raule, Nicola; Chomyn, Anne; Attardi, Giuseppe

2012-10-29

191

Simvastatin Inhibits C-Reactive Protein-Induced Pro-Inflammatory Changes in Endothelial Cells by Decreasing Mevalonate Pathway Products  

Microsoft Academic Search

Objectives: The effects of HMG-CoA reductase inhibitors on C-reactive protein (CRP)-induced pro-inflammatory changes in endothelial cells remain unclear. We tested the hypothesis that simvastatin inhibited CRP-induced pro-inflammatory changes in endothelial cells by decreasing mevalonate pathway products. Methods: Human umbilical vein endothelial cells were incubated with CRP and measurement of CD32, nuclear factor ?B (NF-?B) activation, vascular cell adhesion molecule-1 expression

Yao-Jen Liang; Kou-Gi Shyu; Bao-Wie Wang; Ling-Ping Lai

2008-01-01

192

Reactive oxygen species production and antioxidative defense system in pea root tissues treated with lead ions: the whole roots level  

Microsoft Academic Search

The lead absorbed by the roots induce oxidative stress conditions through the Reactive oxygen species (ROS) production for\\u000a the pea plants cultivated hydroponically for 96 h on a Hoagland medium with the addition of 0.1 and 0.5 mM of Pb(NO3)2. The alterations in $$ {\\\\text{O}}_{2}^{ - \\\\cdot } $$ and H2O2 concentrations were monitored spectrophotometrically which show a rapid increase in $$

Arleta Malecka; Aneta Piechalak; Barbara Tomaszewska

2009-01-01

193

Endothelial Nitric Oxide Synthase Reduces Crescentic and Necrotic Glomerular Lesions, Reactive Oxygen Production, and MCP1 Production in Murine Lupus Nephritis  

PubMed Central

Systemic lupus erythematosus, in both animal models and in humans, is characterized by autoantibody production followed by immune complex deposition in target tissues. Ensuing target organ damage is modulated by reactive intermediates, including reactive nitrogen and oxygen species, through as of now incompletely understood mechanisms. Endothelial nitric oxide synthase is known to impact vascular reactivity; however its impact on reactive intermediate production and inflammatory renal disease is less well defined. In this study, we assessed the impact of endothelial nitric oxide synthase (eNOS) on disease in lupus prone MRL/lpr mice. Mice lacking eNOS developed earlier more severe disease with decreased survival. eNOS deficient mice died sooner and developed significantly more glomerular crescents, necrosis, inflammatory infiltrates and vasculitis, indicating a role for eNOS in modulating these renal lesions. Immune complex deposition was similar between groups, indicating the impact of eNOS is distal to antibody/complement glomerular deposition. Urinary nitric oxide production was decreased in the eNOS deficient mice, while proteinuria was increased. Urinary monocyte chemotactic protein-1 was also increased in the knockout mice. CD4+ T cells from MRL/lpr mice demonstrated mitochondrial hyperpolarization, increased nitric oxide and superoxide production and increased calcium flux compared to B6 control mice. Deficiency of eNOS resulted in decreased nitric oxide and mitochondrial calcium levels but had no effect on mitochondrial hyperpolarization. Renal cortices from MRL/lpr mice that are eNOS deficient demonstrated increased superoxide production, which was blocked by both nitric oxide synthase and NADPH oxidase inhibitors. These studies thus demonstrate a key role for eNOS in modulating renal disease in lupus prone MRL/lpr mice. The impact appears to be mediated by effects on superoxide production in the kidney, impacting downstream mediators such as monocyte chemotactic protein-1. These results suggest that modulation of eNOS may be a novel therapeutic approach to treating lupus nephritis.

Gilkeson, Gary S.; Mashmoushi, Ahmad K.; Ruiz, Phillip; Caza, Tiffany N.; Perl, Andras; Oates, Jim C.

2013-01-01

194

Single Higgs-boson production through ?? scattering within the general 2HDM  

NASA Astrophysics Data System (ADS)

The production of a single neutral Higgs boson h through (loop-induced) ?? collisions is explored in the context of the linear colliders within the general Two-Higgs-Doublet Model (2HDM). Two different mechanisms are analyzed: on the one hand, the scattering ???h of two real photons in a ?? collider; on the other, the more traditional mechanism of virtual photon fusion, ee?ee???ee+h. Owing to the peculiar properties of the Higgs boson self-interactions within the general 2HDM, we find that the overall production rates can be boosted up significantly, provided the charged Higgs mass is not too heavy. For example, if M?100 GeV and, in addition, M falls in the ballpark of the LEP bound on the SM Higgs mass up to a few hundred GeV, the cross-sections may typically render ˜0.1-1 pb and ?(ee?eeh)?0.01 pb - in both cases well above the SM prediction. Although for M>300 GeV the rates become virtually insensitive to the Higgs boson self-couplings, a significant tail of non-SM effects produced by the combined contribution of the Yukawa couplings and gauge bosons could still reveal a smoking gun.

Bernal, Nicolás; López-Val, David; Solà, Joan

2009-06-01

195

Glucosinolate degradation products, isothiocyanates, nitriles, and thiocyanates, induce stomatal closure accompanied by peroxidase-mediated reactive oxygen species production in Arabidopsis thaliana.  

PubMed

Isothiocyanates, nitriles, and thiocyanates are degradation products of glucosinolates in crucifer plants. In this study, we investigated the stomatal response to allyl isothiocyanate (AITC), 3-butenenitrile (3BN), and ethyl thiocyanate (ESCN) in Arabidopsis. AITC, 3BN, and ESCN induced stomatal closure in the wild type and the atrbohD atrbohF mutant. Stomatal closure was inhibited by catalase and salicylhydroxamic acid (SHAM). The degradation products induced extracellular reactive oxygen species (ROS) production in the rosette leaves, and intracellular ROS accumulation, NO production, and cytosolic free calcium concentration ([Ca(2+)]cyt) oscillations in guard cells, which were inhibited by SHAM. These results suggest that glucosinolate degradation products induce stomatal closure accompanied by extracellular ROS production mediated by SHAM-sensitive peroxidases, intracellular ROS accumulation, and [Ca(2+)]cyt oscillation in Arabidopsis. PMID:23649257

Hossain, Mohammad Shakhawat; Ye, Wenxiu; Hossain, Mohammad Anowar; Okuma, Eiji; Uraji, Misugi; Nakamura, Yoshimasa; Mori, Izumi C; Murata, Yoshiyuki

2013-05-07

196

Norepinephrine causes epigenetic repression of PKC? gene in rodent hearts by activating Nox1-dependent reactive oxygen species production  

PubMed Central

Heart disease is the leading cause of death in the United States. Recent studies demonstrate that fetal programming of PKC? gene repression results in ischemia-sensitive phenotype in the heart. The present study tests the hypothesis that increased norepinephrine causes epigenetic repression of PKC? gene in the heart via Nox1-dependent reactive oxygen species (ROS) production. Prolonged norepinephrine treatment increased ROS production in fetal rat hearts and embryonic ventricular myocyte H9c2 cells via a selective increase in Nox1 expression. Norepinephrine-induced ROS resulted in an increase in PKC? promoter methylation at Egr-1 and Sp-1 binding sites, leading to PKC? gene repression. N-acetylcysteine, diphenyleneiodonium, and apocynin blocked norepinephrine-induced ROS production and the promoter methylation, and also restored PKC? mRNA and protein to control levels in vivo in fetal hearts and in vitro in embryonic myocyte cells. Accordingly, norepinephrine-induced ROS production, promoter methylation, and PKC? gene repression were completely abrogated by knockdown of Nox1 in cardiomyocytes. These findings provide evidence of a novel interaction between elevated norepinephrine and epigenetic repression of PKC? gene in the heart mediated by Nox1-dependent oxidative stress and suggest new insights of molecular mechanisms linking the heightened sympathetic activity to aberrant cardioprotection and increased ischemic vulnerability in the heart.—Xiong, F., Xiao, D., Zhang, L. Norepinephrine causes epigenetic repression of PKC? gene in rodent hearts by activating Nox1-dependent reactive oxygen species production.

Xiong, Fuxia; Xiao, Daliao; Zhang, Lubo

2012-01-01

197

Coherent production of rho mesons in muon-carbon scattering at 150 and 100 GeV  

SciTech Connect

We have observed coherent production of rho mesons by muon scattering on carbon. The differential cross section falls steeply with increasing t (the square of the four-momentum transferred to the nucleus) and helicity is conserved in the s channel. Dominance by coherent production, as well as the radius of the carbon nucleus and the total rho-nucleus cross section derived from our measurements, are consistent with what is observed in other related processes.

Shambroom, W.D.; Gordon, B.A.; Loomis, W.A.; Pipkin, F.M.; Pordes, S.H.; Verhey, L.J.; Wilson, R.; Anderson, H.L.; Fine, R.M.; Heisterberg, R.H.; Matis, H.S.; Mo, L.W.; Myrianthopoulos, L.C.; Wright, S.C.; Francis, W.R.; Hicks, R.G.; Kirk, T.B.W.; Bharadwaj, V.K.; Booth, N.E.; Kirkbride, G.I.; Quirk, T.W.; Skuja, A.; Williams, W.S.C.

1981-08-01

198

Effect of resveratrol, a natural polyphenolic compound, on reactive oxygen species and prostaglandin production  

Microsoft Academic Search

Resveratrol is a natural molecule with antioxidant action. Moreover, resveratrol is also considered to be a molecule with anti-inflammatory action, an effect attributed to suppression of prostaglandin (PG) biosynthesis. The aim of the present study was to investigate the effects of resveratrol, a polyphenol present in most red wines, on reactive oxygen species formation as well as on arachidonic acid

Javier Martinez; Juan J Moreno

2000-01-01

199

Increase in Reactive Nitrogen Species Production in Chronic Obstructive Pulmonary Disease Airways  

Microsoft Academic Search

Peroxynitrite, nitrogen dioxide, and other reactive nitrogen spe- cies (RNS) that are formed in the reaction of nitric oxide (NO) with superoxide anion, and in peroxidase-dependent mechanisms, have a potent inflammatory action. These molecules may there- fore increase in number and have a role in inflammatory airway diseases. In the present study, we quantified RNS using immun- ostaining of nitrotyrosine

MASAKAZU ICHINOSE; HISATOSHI SUGIURA; SHUNSUKE YAMAGATA; AKIRA KOARAI; KUNIO SHIRATO

2000-01-01

200

Hybrid reactive distillation systems for n-butyl acetate production from dilute acetic acid  

Microsoft Academic Search

The recovery of dilute acetic acid, regarding as a waste stream in many chemical and petrochemical processes, becomes an important issue due to economic and environmental awareness. In this work, a simulation study on the direct utilization of dilute acetic acid to produce n-butyl acetate via esterification with butanol in a reactive distillation is presented by using Aspen Plus. The

Amornchai Arpornwichanop; Kittipong Koomsup; Suttichai Assabumrungrat

2008-01-01

201

Oxidants, Antioxidants, and the Beneficial Roles of Exercise-Induced Production of Reactive Species  

PubMed Central

This review offers an overview of the influence of reactive species produced during exercise and their effect on exercise adaptation. Reactive species and free radicals are unstable molecules that oxidize other molecules in order to become stable. Although they play important roles in our body, they can also lead to oxidative stress impairing diverse cellular functions. During exercise, reactive species can be produced mainly, but not exclusively, by the following mechanisms: electron leak at the mitochondrial electron transport chain, ischemia/reperfusion and activation of endothelial xanthine oxidase, inflammatory response, and autooxidation of catecholamines. Chronic exercise also leads to the upregulation of the body's antioxidant defence mechanism, which helps minimize the oxidative stress that may occur after an acute bout of exercise. Recent studies show a beneficial role of the reactive species, produced during a bout of exercise, that lead to important training adaptations: angiogenesis, mitochondria biogenesis, and muscle hypertrophy. The adaptations occur depending on the mechanic, and consequently biochemical, stimulus within the muscle. This is a new area of study that promises important findings in the sphere of molecular and cellular mechanisms involved in the relationship between oxidative stress and exercise.

Gomes, Elisa Couto; Silva, Albena Nunes; de Oliveira, Marta Rubino

2012-01-01

202

Moderators of cardiovascular reactivity to speech: discourse production and group variations in blood pressure and pulse rate.  

PubMed

To explain why speech produces cardiovascular reactivity, an experiment utilized speech tasks varying in self-disclosure and cognitive preparation and measured the blood pressure and pulse rate of African-American and Caucasian, men and women subjects. One hundred and fifty-six college students with a median age of 21 volunteered to participate. The extemporaneous speech task produced lower systolic blood pressure than the prepared speech task. Self-disclosive speech resulted in lower diastolic blood pressure than non-disclosive speech. Females showed higher pulse rate and men exhibited greater diastolic blood pressure while speaking. Results supported previous research suggesting that women are myocardiacal hyperreactors, while men are vascular hypperreactors and suggest that production processes moderate cardiovascular reactivity to speech. PMID:9666379

Tardy, C H; Allen, M T

1998-08-01

203

Reactions of peroxynitrite with uric acid: formation of reactive intermediates, alkylated products and triuret, and in vivo production of triuret under conditions of oxidative stress.  

PubMed

Hyperuricemia is associated with hypertension, metabolic syndrome, preeclampsia, cardio-vascular disease and renal disease, all conditions associated with oxidative stress. We hypothesized that uric acid, a known antioxidant, might become prooxidative following its reaction with oxidants; and, thereby contribute to the pathogenesis of these diseases. Uric acid and 1,3-(15)N(2)-uric acid were reacted with peroxynitrite in different buffers and in the presence of alcohols, antioxidants and in human plasma. The reaction products were identified using liquid chromatography-mass spectrometry (LC-MS) analyses. The reactions generate reactive intermediates that yielded triuret as their final product. We also found that the antioxidant, ascorbate, could partially prevent this reaction. Whereas triuret was preferentially generated by the reactions in aqueous buffers, when uric acid or 1,3-(15)N(2)-uric acid was reacted with peroxynitrite in the presence of alcohols, it yielded alkylated alcohols as the final product. By extension, this reaction can alkylate other biomolecules containing OH groups and others containing labile hydrogens. Triuret was also found to be elevated in the urine of subjects with preeclampsia, a pregnancy-specific hypertensive syndrome that is associated with oxidative stress, whereas very little triuret is produced in normal healthy volunteers. We conclude that under conditions of oxidative stress, uric acid can form reactive intermediates, including potential alkylating species, by reacting with peroxynitrite. These reactive intermediates could possibly explain how uric acid contributes to the pathogenesis of diseases such as the metabolic syndrome and hypertension. PMID:19219741

Gersch, Christine; Palii, Sergiu P; Imaram, Witcha; Kim, Kyung Mee; Karumanchi, S Ananth; Angerhofer, Alexander; Johnson, Richard J; Henderson, George N

2009-02-01

204

REACTIONS OF PEROXYNITRITE WITH URIC ACID: FORMATION OF REACTIVE INTERMEDIATES, ALKYLATED PRODUCTS AND TRIURET, AND IN VIVO PRODUCTION OF TRIURET UNDER CONDITIONS OF OXIDATIVE STRESS  

PubMed Central

Hyperuricemia is associated with hypertension, metabolic syndrome, preeclampsia, cardiovascular disease and renal disease, all conditions associated with oxidative stress. We hypothesized that uric acid, a known antioxidant, might become prooxidative following its reaction with oxidants; and, thereby contribute to the pathogenesis of these diseases. Uric acid and 1,3-15N2-uric acid were reacted with peroxynitrite in different buffers and in the presence of alcohols, antioxidants and in human plasma. The reaction products were identified using liquid chromatography-mass spectrometry (LC-MS) analyses. The reactions generate reactive intermediates that yielded triuret as their final product. We also found that the antioxidant, ascorbate, could partially prevent this reaction. Whereas triuret was preferentially generated by the reactions in aqueous buffers, when uric acid or 1,3-15N2-uric acid was reacted with peroxynitrite in the presence of alcohols, it yielded alkylated alcohols as the final product. By extension, this reaction can alkylate other biomolecules containing OH groups and others containing labile hydrogens. Triuret was also found to be elevated in the urine of subjects with preeclampsia, a pregnancy-specific hypertensive syndrome that is associated with oxidative stress, whereas very little triuret is produced in normal healthy volunteers. We conclude that under conditions of oxidative stress, uric acid can form reactive intermediates, including potential alkylating species, by reacting with peroxynitrite. These reactive intermediates could possibly explain how uric acid contributes to the pathogenesis of diseases such as the metabolic syndrome and hypertension.

Gersch, Christine; Palii, Sergiu P.; Imaram, Witcha; Kim, Kyung Mee; Karumanchi, S. Ananth; Angerhofer, Alexander; Johnson, Richard J.; Henderson, George N.

2009-01-01

205

PROBING REACTIVITY OF DISSOLVED ORGANIC MATTER FOR DISINFECTION BY-PRODUCT FORMATION USING XAD-8 RESIN ADSORPTION AND ULTRAFILTRATION FRACTIONATION. (R828045)  

EPA Science Inventory

The disinfection by-product (DBP) reactivity (yield and speciation upon reaction with chlorine) of dissolved organic matter (DOM) isolated from two surface waters was investigated. The source waters, each having significantly different specific ultraviolet absorbance (SUVA...

206

X-ray mapping and scatter diagram analysis of the discoloring products resulting from the interaction of artist's pigments.  

PubMed

The discoloring interaction between the artist's pigments cadmium yellow and the copper-containing malachite, an interaction that is conjectured to cause black spotting in oil paintings of the 19th and early 20th centuries, was examined using X-ray mapping and scatter diagram analysis. The application of these coupled techniques confirmed that copper sulfide phases were produced during discoloration reaction. Scatter diagram analysis indicated that two copper sulfide stoichiometries (CuS and Cu3S2) were present as reaction products where previously only crystalline CuS (covellite) had been identified by X-ray diffraction. The results demonstrate the potential of X-ray mapping coupled with scatter diagram analysis for the identification of both crystalline and X-ray amorphous phases produced by such complex heterogeneous interactions and their applicability to the investigation of interactions of artists' pigments. PMID:20804641

White, Rachel; Thomas, Paul; Phillips, Matthew R; Moran, Ken; Wuhrer, Richard

2010-08-31

207

Multijet production at low x{sub Bj} in deep inelastic scattering at HERA.  

SciTech Connect

Inclusive dijet and trijet production in deep inelastic ep scattering has been measured for 10 < Q{sup 2} < 100 GeV{sup 2} and low Bjorken x, 10{sup -4} <{sub Bj}<10{sup -2}. The data were taken at the HERA ep collider with center-of-mass energy {radical}s = 318 GeV using the ZEUS detector and correspond to an integrated luminosity of 82 pb{sup -1}. Jets were identified in the hadronic center-of-mass (HCM) frame using the k{sub T} cluster algorithm in the longitudinally invariant inclusive mode. Measurements of dijet and trijet differential cross sections are presented as functions of Q{sup 2}, x{sub Bj}, jet transverse energy, and jet pseudorapidity. As a further examination of low-x{sub Bj} dynamics, multi-differential cross sections as functions of the jet correlations in transverse momenta, azimuthal angles, and pseudorapidity are also presented. Calculations at {Omicron}({alpha}{sub s}{sup 2}) generally describe the trijet data well and improve the description of the dijet data compared to the calculation at {Omicron}({alpha}{sub s}{sup 2}).

Chekanov, S.; Derrick, M.; Magill, S.; Musgrave, B.; Nicholass, D.; Repond, J.; Yoshida, R.; High Energy Physics; ZEUS Collaboration

2007-12-10

208

Increased Adhesion Molecules Expression and Production of Reactive Oxygen Species in Leukocytes of Sleep Apnea Patients  

Microsoft Academic Search

Obstructive sleep apnea (OSA) is associated with increased cardio- vascular morbidity and mortality. Free radicals and adhesion mole- cules were implicated in the pathogenesis of atherosclerosis lead- ing to cardiovascular disorders. Therefore, we investigated the link between CD15, CD11c, CD11b, and CD64 expression on leukocytes and their ability to generate reactive oxygen species (ROS) in pa- tients with OSA and

LARISSA DYUGOVSKAYA; PERETZ LAVIE; LENA LAVIE

209

Interactive effects of avoidant coping and parental hypertension on Rate Pressure Product reactivity in women  

Microsoft Academic Search

Background: Previous research suggests that personality, situational context variables, and genes might interact to potentiate cardiovascular\\u000a stress responses.Purpose: Our purpose is to examine interactive effects of dispositional avoidant coping and parental hypertension on cardiovascular\\u000a reactivity to three different laboratory stressors.Method: Participants were 63 healthy female students. Stressors were an evaluated videotaped speech, the cold pressor, and viewing\\u000a of the speech

Andreas Schwerdtfeger; Stefan C. Schmukle; Boris Egloff

2005-01-01

210

Cytokines and C-Reactive Protein Production in Hip-Fracture-Operated Elderly Patients  

Microsoft Academic Search

Background. The study aim was to determine the kinetics of serum pro- and anti-inflammatory cytokines and C-reactive protein (CRP) in hip-fracture patients over a month postfracture, and their relationship to postoperative (postop) complications and cognitive level. Methods. Forty-one elderly hip-fracture patients were prospectively followed. Serum was obtained during the first 10 hours postfracture and presurgery, 48-60 hours postop, 7 and

Yichayaou Beloosesky; David Hendel; Avraham Weiss; Avital Hershkovitz; Joseph Grinblat; Anatoly Pirotsky; Vivian Barak

2007-01-01

211

Production and characterization of mouse monoclonal antibodies reactive to Chikungunya envelope E2 glycoprotein.  

PubMed

Chikungunya fever is an arbovirosis of major impact in public health in Asia and Africa. Chikungunya (CHIK) virus is member of the genus Alphavirus and belongs to the Semliki Forest (SF) antigenic complex. We describe for the first time a panel of monoclonal antibodies (MAbs) reactive to CHIK envelope E2 glycoprotein. For the screening of E2-specific MAbs, we expressed a recombinant soluble CHIK E2 protein in Drosophila S2 cells. Analyzed by immunological methods, MAbs 3C3, 3E4, and 8A4 were selected on the basis of their reactivity. Their epitopes are located to the outer surface of CHIK virion. These MAbs have no cross reactivity with related members of SF antigenic complex with the notable exception of Igbo-Ora virus. Anti-CHIK E2 MAbs 3C3, 3E4, and 8A4 should be helpful for studying the biology of CHIK virus and pathogenesis of disease. The combination of 8A4 and 3E4 is suitable for developing a specific antigen-capture ELISA. PMID:17949772

Bréhin, Anne-Claire; Rubrecht, Laetitia; Navarro-Sanchez, Martha Erika; Maréchal, Valérie; Frenkiel, Marie-Pascale; Lapalud, Priscilla; Laune, Daniel; Sall, Amadou Alpha; Desprès, Philippe

2007-10-18

212

Enhancement of chemically induced reactive oxygen species production and DNA damage in human SH-SY5Y neuroblastoma cells by 872 MHz radiofrequency radiation  

Microsoft Academic Search

The objective of the study was to investigate effects of 872MHz radiofrequency (RF) radiation on intracellular reactive oxygen species (ROS) production and DNA damage at a relatively high SAR value (5W\\/kg). The experiments also involved combined exposure to RF radiation and menadione, a chemical inducing intracellular ROS production and DNA damage. The production of ROS was measured using the fluorescent

Jukka Luukkonen; Pasi Hakulinen; Jorma Mäki-Paakkanen; Jukka Juutilainen; Jonne Naarala

2009-01-01

213

Differential effects of temperature on reactive oxygen/nitrogen species production in rat pachytene spermatocytes and round spermatids.  

PubMed

Reactive oxygen species (ROS) and reactive nitrogen species (RNS) like superoxide and nitric oxide are produced by testis and spermatogenic cells in response to heat stress. However, the magnitude and mechanisms of this production in spermatogenic cells have not been described. In this work, we evaluated ROS/RNS production, its pharmacology, mitochondrial oxidative metabolism, membrane potential and antioxidant capacity at different temperatures in isolated rat pachytene spermatocytes and round spermatids. Our results showed an increment in ROS/RNS production by pachytene spermatocytes when increasing the temperature to 40?°C. Instead, ROS/RNS production by round spermatids did not change at temperatures higher than 33?°C. ROS/RNS production was sensitive to NADPH oxidase inhibitor diphenylene iodonium or the mitochondrial complex I inhibitor rotenone. No additive effects were observed for these two compounds. Our results suggest an important mitochondrial ROS/RNS production in spermatogenic cells. Oligomycin-insensitive oxygen consumption (uncoupled oxygen consumption) increased with temperature and was significantly larger in round spermatids than pachytene spermatocytes, indicating a likely round spermatid mitochondrial uncoupling at high temperatures. A similar conclusion can be reached by measuring the mitochondrial membrane potential using rhodamine 123 fluorescence in permeabilized cells or JC-1 fluorescence in intact cells. The antioxidant capacity was higher in round spermatids than pachytene spermatocytes at 40?°C. Our results strongly suggest that at high temperatures (40?°C) pachytene spermatocytes are more susceptible to oxidative stress, but round spermatids are more protected because of a temperature-induced mitochondrial uncoupling together with a larger antioxidant capacity. PMID:23241345

Pino, José A; Osses, Nelson; Oyarzún, Daniela; Farías, Jorge G; Moreno, Ricardo D; Reyes, Juan G

2013-01-24

214

Controlling reactivity of nanoporous catalyst materials by tuning reaction product-pore interior interactions: Statistical mechanical modeling  

NASA Astrophysics Data System (ADS)

Statistical mechanical modeling is performed of a catalytic conversion reaction within a functionalized nanoporous material to assess the effect of varying the reaction product-pore interior interaction from attractive to repulsive. A strong enhancement in reactivity is observed not just due to the shift in reaction equilibrium towards completion but also due to enhanced transport within the pore resulting from reduced loading. The latter effect is strongest for highly restricted transport (single-file diffusion), and applies even for irreversible reactions. The analysis is performed utilizing a generalized hydrodynamic formulation of the reaction-diffusion equations which can reliably capture the complex interplay between reaction and restricted transport.

Wang, Jing; Ackerman, David M.; Lin, Victor S.-Y.; Pruski, Marek; Evans, James W.

2013-04-01

215

Antigen-reactive T cell clones. I. Transcomplementing hybrid I-A-region gene products function effectively in antigen presentation  

PubMed Central

Studies in our laboratory and elsewhere have shown that it is possible to propagate antigen-specific murine T cells in vitro with resultant specific stepwise enrichment of antigen-induced proliferative cells. The proliferative responses of these T cells are antigen specific and dependent upon the presence of antigen-presenting cells (spleen cells) that share the I-A subregion with the proliferating T cell. Using techniques of soft-agar cloning, it has been further possible to isolate clones of antigen-reactive T lymphocytes from such long-term cultures. Data suggesting that these were clones of antigen-reactive T cells were obtained by studying the recognition of antigen in association with antigen-presenting cells with a panel of such clones of antigen-reactive T cells. Proof of clonality was obtained by subcloning. Clones derived from F1-immune mice can be divided into three separate categories: one clone recognizes antigen in association with antigen-presenting determinants of parent A and the F1; the second type recognizes antigen in association with antigen-presenting determinants of parent B and the F1; and the third type recognizes antigen only in association with antigen-presenting determinants of the F1 mouse. Genetic studies on the major histocompatibility complex requirements for antigen presentation to such F1-reactive T cell clones suggests that the hybrid antigen-presenting determinant in this system results from transcomplementation of products of the I-A region of haplotypes a and b. These studies support the concept developed in our laboratory that there exist unique F1 hybrid determinants on (A/J X C57BL/6) F1 cells and suggest that these determinants can be utilized physiologically by hybrid mice in immunocompetent cellular interactions.

1980-01-01

216

Benidipine, an anti-hypertensive drug, inhibits reactive oxygen species production in polymorphonuclear leukocytes and oxidative stress in salt-loaded stroke-prone spontaneously hypertensive rats.  

PubMed

Oxidative stress is associated with exacerbation of renal injuries in hypertension. In clinical studies benidipine hydrochloride (benidipine), a dihydropyridine calcium channel blocker with antioxidant activity, reduced oxidative stress. However, the mechanism of suppression of oxidative stress remains to be fully characterized. Reactive oxygen species production by polymorphonuclear leukocyte plays important pathological roles in hypertension. Therefore, we examined the effects of benidipine both on reactive oxygen species production of human polymorphonuclear leukocytes and oxidative stress of an animal model. Human peripheral polymorphonuclear leukocytes or polymorphonuclear leukocyte-like differentiated HL-60 cells were used to examine effects of benidipine (0.1-30 microM) on formyl-Met-Leu-Phe-induced reactive oxygen species production, calcium mobilization, NADPH oxidase activation and phosphorylation of protein kinase C substrates. High-salt (8% NaCl) loaded stroke-prone spontaneously hypertensive rats were treated with or without benidipine (1, 3, 10 mg/kg/day) for 2 weeks, and thiobarbituric acid reactive substances, a plasma oxidative stress marker, and renal expression of oxidative stress-induced genes were measured. Benidipine concentration-dependently suppressed formyl-Met-Leu-Phe-induced reactive oxygen species production in polymorphonuclear leukocytes more potently than other calcium channel blockers such as amlodipine, azelnidipine, nitrendipine and nifedipine. Benidipine partially inhibited all of intracellular Ca(2+) elevation, protein kinase C activation and NADPH oxidase activation. Salt loading in stroke-prone spontaneously hypertensive rats augmented plasma thiobarbituric acid reactive substances levels; renal dysfunction; and renal expression of transforming growth factor-beta, collagen I and collagen III mRNAs; which were attenuated by benidipine treatment. These results indicate that benidipine prevents the polymorphonuclear leukocyte-derived reactive oxygen species production, which is due at least in part to its antioxidant action and inhibition of Ca(2+)/protein kinase C/NADPH oxidase signaling. The attenuation of reactive oxygen species production might contribute to the drug's reduction of oxidative stress and renal injuries in hypertension. PMID:18048030

Matsubara, Masahiro; Akizuki, Osamu; Ikeda, Jun-ichi; Saeki, Koji; Yao, Kozo; Sasaki, Katsutoshi

2007-11-01

217

The impact of dehydration rate on the production and cellular location of reactive oxygen species in an aquatic moss  

PubMed Central

Background and Aims The aquatic moss Fontinalis antipyretica requires a slow rate of dehydration to survive a desiccation event. The present work examined whether differences in the dehydration rate resulted in corresponding differences in the production of reactive oxygen species (ROS) and therefore in the amount of cell damage. Methods Intracellular ROS production by the aquatic moss was assessed with confocal laser microscopy and the ROS-specific chemical probe 2,7-dichlorodihydrofluorescein diacetate. The production of hydrogen peroxide was also quantified and its cellular location was assessed. Key Results The rehydration of slowly dried cells was associated with lower ROS production, thereby reducing the amount of cellular damage and increasing cell survival. A high oxygen consumption burst accompanied the initial stages of rehydration, perhaps due to the burst of ROS production. Conclusions A slow dehydration rate may induce cell protection mechanisms that serve to limit ROS production and reduce the oxidative burst, decreasing the number of damaged and dead cells due upon rehydration.

Cruz de Carvalho, Ricardo; Catala, Myriam; Marques da Silva, Jorge; Branquinho, Cristina; Barreno, Eva

2012-01-01

218

Photocatalytic reactive oxygen species production and phototoxicity of titanium dioxide nanoparticles are dependent on the solar ultraviolet radiation spectrum.  

PubMed

Generation of reactive oxygen species (ROS) by titanium dioxide nanoparticles (nano-TiO(2)) and its consequent phototoxicity to Daphnia magna were measured under different solar ultraviolet (UV) spectra by applying a series of optical filters in a solar simulator. Removing UV-B (280-320 nm) from solar radiation had no significant impact on photocatalytic ROS production of nano-TiO(2), whereas removal of UV-A (320-400 nm) decreased ROS production remarkably. Removal of wavelengths below 400 nm resulted in negligible ROS production. A linear correlation between ROS production and D. magna immobilization suggests that photocatalytic ROS production may be a predictor of phototoxicity for nano-TiO(2). Intracellular ROS production within D. magna was consistent with the immobilization of the organism under different solar UV spectra, indicating that oxidative stress was involved in phototoxicity. The dependence of nano-TiO(2) phototoxicity on environmentally realistic variations in solar radiation suggests that risk assessment of these nanomaterials requires careful evaluation of exposure conditions in the environment. PMID:22707245

Ma, Hongbo; Brennan, Amanda; Diamond, Stephen A

2012-07-22

219

Higgs boson production and the scattering of longitudinally polarized vector bosons at very high energy electron-positron colliders  

Microsoft Academic Search

A detailed discussion is presented of rates and backgrounds for studying Higgs boson production and WLWL, ZLZL, WLZL scattering at very high energy e+e- colliders. The ee --> eeWW, gammagammaWW backgrounds limit the reach for discovering Higgs bosons. Strong interaction effects, which must develop for invariant masses above 1 TeV if there is no Higgs boson or if MH is

M. C. Bento; C. H. Llewellyn Smith

1987-01-01

220

Gamma ray production cross-sections associated with multiple inelastic scattering of 14 MeV neutrons in lead  

NASA Astrophysics Data System (ADS)

The gamma ray angular distributions and differential production cross-sections have been measured for the inelastic scattering of 14 MeV neutrons in lead, using a gamma ray spectrometer based on an associated particle time-of-flight gating technique. The variation of cross-section with sample thickness was measured and the results compared with the predictions of the Monte Carlo computer code MORSE.

Warner, P. C.; Cox, A. J.

1985-11-01

221

Ozone production rate and hydrocarbon reactivity in 5 urban areas: A cause of high ozone concentration in Houston  

NASA Astrophysics Data System (ADS)

Observations of ozone (O3) and O3 precursors taken from aircraft flights over Houston, TX, Nashville, TN; New York, NY; Phoenix, AZ, and Philadelphia, PA show that high concentrations of reactive volatile organic compounds (VOCs) in the Houston atmosphere lead to calculated O3 production rates that are 2 to 5 times higher than in the other 4 cities even though NOx concentrations are comparable. Within the Houston metropolitan area, concentrations of VOCs and O3 production rates are highest in the Ship Channel region; the location of one of the largest petrochemical complexes in the world. As a consequence the concentration of O3 in the Houston metropolitan area has recently exceeded 250 ppb, the highest value observed in the U.S within the past 5 years.

Kleinman, L. I.; Daum, P. H.; Imre, D.; Lee, Y.-N.; Nunnermacker, L. J.; Springston, S. R.; Weinstein-Lloyd, J.; Rudolph, J.

2002-05-01

222

Ca2+ Regulates Reactive Oxygen Species Production and pH during Mechanosensing in Arabidopsis Roots[C][W  

PubMed Central

Mechanical stimulation of plants triggers a cytoplasmic Ca2+ increase that is thought to link the touch stimulus to appropriate growth responses. We found that in roots of Arabidopsis thaliana, external and endogenously generated mechanical forces consistently trigger rapid and transient increases in cytosolic Ca2+ and that the signatures of these Ca2+ transients are stimulus specific. Mechanical stimulation likewise elicited an apoplastic alkalinization and cytoplasmic acidification as well as apoplastic reactive oxygen species (ROS) production. These responses showed the same kinetics as mechanically induced Ca2+ transients and could be elicited in the absence of a mechanical stimulus by artificially increasing Ca2+ concentrations. Both pH changes and ROS production were inhibited by pretreatment with a Ca2+ channel blocker, which also inhibited mechanically induced elevations in cytosolic Ca2+. In trichoblasts of the Arabidopsis root hair defective2 mutant, which lacks a functional NADPH oxidase RBOH C, touch stimulation still triggered pH changes but not the local increase in ROS production seen in wild-type plants. Thus, mechanical stimulation likely elicits Ca2+-dependent activation of RBOH C, resulting in ROS production to the cell wall. This ROS production appears to be coordinated with intra- and extracellular pH changes through the same mechanically induced cytosolic Ca2+ transient.

Monshausen, Gabriele B.; Bibikova, Tatiana N.; Weisenseel, Manfred H.; Gilroy, Simon

2009-01-01

223

Increased reactive oxygen species production and p47phox phosphorylation in neutrophils from myeloproliferative disorders patients with JAK2 (V617F) mutation  

PubMed Central

Myeloproliferative disorders are associated with increased risk of thrombosis and vascular complications. The pathogenesis of these complications is not completely known. Reactive oxygen species produced by the neutrophil NADPH oxidase could have a role in this process. The aim of this study was to evaluate reactive oxygen species production by neutrophils of myeloproliferative disorder patients. Patients with or without the JAK2 V617F mutation were characterized. Reactive oxygen species production was assessed by chemiluminescence, and phosphorylation of the NADPH oxidase subunit p47phox was analyzed by Western blots. In a comparison of controls and myeloproliferative disorder patients without the JAK2 V617F mutation, reactive oxygen species production by neutrophils from patients with the JAK2 V617F mutation was dramatically increased in non-stimulated and in stimulated conditions. This increase was associated with increased phosphorylation of the p47phox on Ser345 and of the uspstream kinase ERK1/2. In neutrophils from healthy donors, JAK2 can be activated by GM-CSF. GM-CSF-induced p47phox phosphorylation and priming of reactive oxygen species production are inhibited by the selective JAK2 inhibitors AG490 and lestaurtinib (CEP-701), supporting a role for JAK2 in the upregulation of NADPH oxidase activation. These findings show an increase in reactive oxygen species production and p47phox phosphorylation in neutrophils from myeloproliferative disorder patients with the JAK2 V617F mutation, and demonstrate that JAK2 is involved in GM-CSF-induced NADPH oxidase hyperactivation. As neutrophil hyperactivation could be implicated in the thrombophilic status of patients with myeloproliferative disorders, aberrant activation of JAK2 V617F, leading to excessive neutrophil reactive oxygen species production might play a role in this setting.

Hurtado-Nedelec, Margarita; Csillag-Grange, Marie-Jose; Boussetta, Tarek; Belambri, Sahra Amel; Fay, Michele; Cassinat, Bruno; Gougerot-Pocidalo, Marie-Anne; Dang, Pham My-Chan; El-Benna, Jamel

2013-01-01

224

Most Virus-specific Polypeptides in Cells Productively Infected with Marek's Disease Virus or Herpesvirus of Turkeys Possess Cross-reactive Determinants  

Microsoft Academic Search

SUMMARY Most virus-specific polypeptides in cells productively infected with Marek's disease virus (MDV) or herpesvirus of turkeys (HVT) possess cross-reactive antigenic determinants, although the two viruses have very little DNA homology. The cross- reactivity appeared to be more evident when (35S)methionine-labelled polypeptides were immunoprecipitated than when the (3H)glucosamine-labeUed polypeptides were immunoprecipitated, suggesting that the glycoproteins of MDV and HVT may

KAZUYOSHI IKUTA; SHIGEHARU UEDA; SHIRO KATO; KANJI HIRAI

1983-01-01

225

Feasibility study of a thermally coupled reactive distillation process for biodiesel production  

Microsoft Academic Search

Biodiesel fuel represents an interesting alternative as a clean and renewable substitute of fossil fuels. A typical biodiesel production process involves the use of a catalyst, which implies high energy consumptions for the separation of the catalyst and the by-products of the reaction, including those of undesirable side reactions (such as the saponification reaction). A recently proposed process involves the

Fernando Israel Gomez-Castro; Vicente Rico-Ramirez; Juan Gabriel Segovia-Hernandez; Salvador Hernandez

2010-01-01

226

Nonphosphate Degradation Products of Tributyl Phosphate and Their Reactivities in Purex Media Under Extreme Conditions  

SciTech Connect

The chemical degradation of tributyl phosphate (TBP) in liquid systems, where TBP was in contact with aqueous solutions containing nitric acid and/or uranyl nitrate, was studied experimentally to clarify the mechanisms of the formation and successive reactions of nonphosphate products under atmospheric pressure. Butyl nitrate, propionic acid, acetic acid, butric acid, and butyl alcohol were formed as the nonphosphate butyl products derived from the butyl-groups of TBP in an open system. The total amount of these products almost equals the amount of the major intermediate phosphate products reduced, i.e., di- and monobutyl phosphates and phosphoric acid. Butyl alcohol was found to be the precursor of the other nonphosphate products.Even when the extremely degraded solvent was further contacted with 10 M nitric acid at 90 deg. C, no significant heat evolution was observed at atmospheric pressure. Only butyl alcohol changed into carboxylic acids by exothermic oxidative reactions.

Tashiro, Yoshikazu [Sumitomo Metal Mining Company, Ltd. (Japan); Kodama, Ryuji [Sumitomo Metal Mining Company, Ltd. (Japan); Sugai, Hiroshi [Sumitomo Metal Mining Company, Ltd. (Japan); Suzuki, Katsuhiko [Japan Nuclear Fuel, Ltd. (Japan); Matsuoka, Shingo [Japan Nuclear Fuel, Ltd. (Japan)

2000-01-15

227

Contribution of the FAD and quinone binding sites to the production of reactive oxygen species from Ascaris suum mitochondrial complex II  

Microsoft Academic Search

Reactive oxygen species (ROS) production from mitochondrial complex II (succinate–quinone reductase, SQR) has become a focus of research recently since it is implicated in carcinogenesis. To date, the FAD site is proposed as the ROS producing site in complex II, based on studies done on Escherichia coli, whereas the quinone binding site is proposed as the site of ROS production

Madhavi P. Paranagama; Kimitoshi Sakamoto; Hisako Amino; Mutsumi Awano; Hideto Miyoshi; Kiyoshi Kita

2010-01-01

228

Is the neutrophil reactive oxygen species production measured by luminol and lucigenin chemiluminescence intra or extracellular? Comparison with DCFH-DA flow cytometry and cytochrome c reduction  

Microsoft Academic Search

Background: Polymorphonuclear neutrophils (PMNs) are crucial in host defense against invading microorganisms through reactive oxygen species (ROS) production. However, generated ROS released in excess into media can damage the host tissue. It is therefore essential, when exploring oxygen species production, to discriminate between its intracellular (IC) and extracellular (EC) localization. Several methods of ROS detection are commonly used. However, the

Florence Caldefie-Chézet; Stephane Walrand; Christophe Moinard; Arlette Tridon; Jacques Chassagne; Marie-Paule Vasson

2002-01-01

229

Mitochondrial reactive oxygen species promote production of proinflammatory cytokines and are elevated in TNFR1-associated periodic syndrome (TRAPS)  

PubMed Central

Reactive oxygen species (ROS) have an established role in inflammation and host defense, as they kill intracellular bacteria and have been shown to activate the NLRP3 inflammasome. Here, we find that ROS generated by mitochondrial respiration are important for normal lipopolysaccharide (LPS)-driven production of several proinflammatory cytokines and for the enhanced responsiveness to LPS seen in cells from patients with tumor necrosis factor receptor-associated periodic syndrome (TRAPS), an autoinflammatory disorder caused by missense mutations in the type 1 TNF receptor (TNFR1). We find elevated baseline ROS in both mouse embryonic fibroblasts and human immune cells harboring TRAPS-associated TNFR1 mutations. A variety of antioxidants dampen LPS-induced MAPK phosphorylation and inflammatory cytokine production. However, gp91phox and p22phox reduced nicotinamide adenine dinucleotide phosphate (NADPH) oxidase subunits are dispensable for inflammatory cytokine production, indicating that NADPH oxidases are not the source of proinflammatory ROS. TNFR1 mutant cells exhibit altered mitochondrial function with enhanced oxidative capacity and mitochondrial ROS generation, and pharmacological blockade of mitochondrial ROS efficiently reduces inflammatory cytokine production after LPS stimulation in cells from TRAPS patients and healthy controls. These findings suggest that mitochondrial ROS may be a novel therapeutic target for TRAPS and other inflammatory diseases.

Bulua, Ariel C.; Simon, Anna; Maddipati, Ravikanth; Pelletier, Martin; Park, Heiyoung; Kim, Kye-Young; Sack, Michael N.; Kastner, Daniel L.

2011-01-01

230

beta-aminobutyric acid primes an NADPH oxidase-dependent reactive oxygen species production during grapevine-triggered immunity.  

PubMed

The molecular mechanisms underlying the process of priming are poorly understood. In the present study, we investigated the early signaling events triggered by beta-aminobutyric acid (BABA), a well-known priming-mediated plant resistance inducer. Our results indicate that, in contrast to oligogalacturonides (OG), BABA does not elicit typical defense-related early signaling events nor defense-gene expression in grapevine. However, in OG-elicited cells pretreated with BABA, production of reactive oxygen species (ROS) and expression of the respiratory-burst oxidase homolog RbohD gene were primed. In response to the causal agent of downy mildew Plasmopara viticola, a stronger ROS production was specifically observed in BABA-treated leaves. This process was correlated with an increased resistance. The NADPH oxidase inhibitor diphenylene iodonium (DPI) abolished this primed ROS production and reduced the BABA-induced resistance (BABA-IR). These results suggest that priming of an NADPH oxidase-dependent ROS production contributes to BABA-IR in the Vitis-Plasmopara pathosystem. PMID:20615112

Dubreuil-Maurizi, Carole; Trouvelot, Sophie; Frettinger, Patrick; Pugin, Alain; Wendehenne, David; Poinssot, Benoît

2010-08-01

231

Reactive processing of formaldehyde and acetaldehyde in aqueous aerosol mimics: surface tension depression and secondary organic products  

NASA Astrophysics Data System (ADS)

The reactive uptake of carbonyl-containing volatile organic compounds (cVOCs) by aqueous atmospheric aerosols is a likely source of particulate organic material. The aqueous-phase secondary organic products of some cVOCs are surface-active. Therefore, cVOC uptake can lead to organic film formation at the gas-aerosol interface and changes in aerosol surface tension. We examined the chemical reactions of two abundant cVOCs, formaldehyde and acetaldehyde, in water and aqueous ammonium sulfate (AS) solutions mimicking tropospheric aerosols. Secondary organic products were identified using Aerosol Chemical Ionization Mass Spectrometry (Aerosol-CIMS), and changes in surface tension were monitored using pendant drop tensiometry. Hemiacetal oligomers and aldol condensation products were identified using Aerosol-CIMS. A hemiacetal sulfate ester was tentatively identified in the formaldehyde-AS system. Acetaldehyde depresses surface tension to 65(±2) dyn cm-1 in pure water and 62(±1) dyn cm-1 in AS solutions. Surface tension depression by formaldehyde in pure water is negligible; in AS solutions, a 9 % reduction in surface tension is observed. Mixtures of these species were also studied in combination with methylglyoxal in order to evaluate the influence of cross-reactions on surface tension depression and product formation in these systems. We find that surface tension depression in the solutions containing mixed cVOCs exceeds that predicted by an additive model based on the single-species isotherms.

Li, Z.; Schwier, A. N.; Sareen, N.; McNeill, V. F.

2011-07-01

232

Reactive processing of formaldehyde and acetaldehyde in aqueous aerosol mimics: surface tension depression and secondary organic products  

NASA Astrophysics Data System (ADS)

The reactive uptake of carbonyl-containing volatile organic compounds (cVOCs) by aqueous atmospheric aerosols is a likely source of particulate organic material. The aqueous-phase secondary organic products of some cVOCs are surface-active. Therefore, cVOC uptake can lead to organic film formation at the gas-aerosol interface and changes in aerosol surface tension. We examined the chemical reactions of two abundant cVOCs, formaldehyde and acetaldehyde, in water and aqueous ammonium sulfate (AS) solutions mimicking tropospheric aerosols. Secondary organic products were identified using Aerosol Chemical Ionization Mass Spectrometry (Aerosol-CIMS), and changes in surface tension were monitored using pendant drop tensiometry. Hemiacetal oligomers and aldol condensation products were identified using Aerosol-CIMS. Acetaldehyde depresses surface tension to 65(±2) dyn cm-1 in pure water (a 10% surface tension reduction from that of pure water) and 62(±1) dyn cm-1 in AS solutions (a 20.6% reduction from that of a 3.1 M AS solution). Surface tension depression by formaldehyde in pure water is negligible; in AS solutions, a 9% reduction in surface tension is observed. Mixtures of these species were also studied in combination with methylglyoxal in order to evaluate the influence of cross-reactions on surface tension depression and product formation in these systems. We find that surface tension depression in the solutions containing mixed cVOCs exceeds that predicted by an additive model based on the single-species isotherms.

Li, Z.; Schwier, A. N.; Sareen, N.; McNeill, V. F.

2011-11-01

233

Cellular Stress Induced by Resazurin Leads to Autophagy and Cell Death Via Production of Reactive Oxygen Species and Mitochondrial Impairment  

PubMed Central

Mitochondrial bioenergetics and reactive oxygen species (ROS) often play important roles in cellular stress mechanisms. In this study we investigated how these factors are involved in the stress response triggered by resazurin (Alamar Blue) in cultured cancer cells. Resazurin is a redox reactive compound widely used as reporter agent in assays of cell biology (e.g. cell viability and metabolic activity) due to its colorimetric and fluorimetric properties. In order to investigate resazurin-induced stress mechanisms we employed cells affording different metabolic and regulatory phenotypes. In HL-60 and Jurkat leukemia cells resazurin caused mitochondrial disintegration, respiratory dysfunction, reduced proliferation, and cell death. These effects were preceded by a burst of ROS, especially in HL-60 cells which also were more sensitive and contained autophagic vesicles. Studies in Rho0 cells (devoid of mitochondrial DNA) indicated that the stress response does not depend on the rates of mitochondrial respiration. The anti-proliferative effect of resazurin was confirmed in native acute myelogenous leukemia (AML) blasts. In conclusion, the data suggest that resazurin triggers cellular ROS production and thereby initiates a stress response leading to mitochondrial dysfunction, reduced proliferation, autophagy and cell degradation. The ability of cells to tolerate this type of stress may be important in toxicity and chemoresistance.

Erikstein, Bjarte Skoe; Hagland, Hanne R?land; Nikolaisen, Julie; Kulawiec, Mariola; Singh, Keshav K.; Gjertsen, Bj?rn Tore; Tronstad, Karl Johan

2010-01-01

234

The Bacterial Fermentation Product Butyrate Influences Epithelial Signaling via Reactive Oxygen Species-Mediated Changes in Cullin-1 Neddylation1  

PubMed Central

The human enteric flora plays a significant role in intestinal health and disease. Populations of enteric bacteria can inhibit the NF-?B pathway by blockade of I?B-? ubiquitination, a process catalyzed by the E3-SCF?-TrCP ubiquitin ligase. The activity of this ubiquitin ligase is regulated via covalent modification of the Cullin-1 subunit by the ubiquitin-like protein NEDD8. We previously reported that interaction of viable commensal bacteria with mammalian intestinal epithelial cells resulted in a rapid and reversible generation of reactive oxygen species (ROS) that modulated neddylation of Cullin-1 and resulted in suppressive effects on the NF-?B pathway. Herein, we demonstrate that butyrate and other short chain fatty acids supplemented to model human intestinal epithelia in vitro and human tissue ex vivo results in loss of neddylated Cul-1 and show that physiological concentrations of butyrate modulate the ubiquitination and degradation of a target of the E3-SCF?-TrCP ubiquitin ligase, the NF-?B inhibitor I?B-?. Mechanistically, we show that physiological concentrations of butyrate induces reactive oxygen species that transiently alters the intracellular redox balance and results in inactivation of the NEDD8-conjugating enzyme Ubc12 in a manner similar to effects mediated by viable bacteria. Because the normal flora produces significant amounts of butyrate and other short chain fatty acids, these data provide a functional link between a natural product of the intestinal normal flora and important epithelial inflammatory and proliferative signaling pathways.

Kumar, Amrita; Wu, Huixia; Collier-Hyams, Lauren S.; Kwon, Young-Man; Hanson, Jason M.; Neish, Andrew S.

2010-01-01

235

Mobile Phone Radiation Induces Reactive Oxygen Species Production and DNA Damage in Human Spermatozoa In Vitro  

PubMed Central

Background In recent times there has been some controversy over the impact of electromagnetic radiation on human health. The significance of mobile phone radiation on male reproduction is a key element of this debate since several studies have suggested a relationship between mobile phone use and semen quality. The potential mechanisms involved have not been established, however, human spermatozoa are known to be particularly vulnerable to oxidative stress by virtue of the abundant availability of substrates for free radical attack and the lack of cytoplasmic space to accommodate antioxidant enzymes. Moreover, the induction of oxidative stress in these cells not only perturbs their capacity for fertilization but also contributes to sperm DNA damage. The latter has, in turn, been linked with poor fertility, an increased incidence of miscarriage and morbidity in the offspring, including childhood cancer. In light of these associations, we have analyzed the influence of RF-EMR on the cell biology of human spermatozoa in vitro. Principal Findings Purified human spermatozoa were exposed to radio-frequency electromagnetic radiation (RF-EMR) tuned to 1.8 GHz and covering a range of specific absorption rates (SAR) from 0.4 W/kg to 27.5 W/kg. In step with increasing SAR, motility and vitality were significantly reduced after RF-EMR exposure, while the mitochondrial generation of reactive oxygen species and DNA fragmentation were significantly elevated (P<0.001). Furthermore, we also observed highly significant relationships between SAR, the oxidative DNA damage bio-marker, 8-OH-dG, and DNA fragmentation after RF-EMR exposure. Conclusions RF-EMR in both the power density and frequency range of mobile phones enhances mitochondrial reactive oxygen species generation by human spermatozoa, decreasing the motility and vitality of these cells while stimulating DNA base adduct formation and, ultimately DNA fragmentation. These findings have clear implications for the safety of extensive mobile phone use by males of reproductive age, potentially affecting both their fertility and the health and wellbeing of their offspring.

De Iuliis, Geoffry N.; Newey, Rhiannon J.; King, Bruce V.; Aitken, R. John

2009-01-01

236

Krebs Cycle Intermediates Modulate Thiobarbituric Acid Reactive Species (TBARS) Production in Rat Brain In Vitro  

Microsoft Academic Search

The aim of this study was to investigate the effect of Krebs cycle intermediates on basal and quinolinic acid (QA)- or iron-induced TBARS production in brain membranes. Oxaloacetate, citrate, succinate and malate reduced significantly the basal and QA-induced TBARS production. The potency for basal TBARS inhibition was in the order (IC50 is given in parenthesis as mM) citrate (0.37) > oxaloacetate (1.33) = succinate

Robson L. Puntel; Cristina W. Nogueira; João B. T. Rocha

2005-01-01

237

Induction of regulatory T cells by macrophages is dependent on production of reactive oxygen species  

PubMed Central

The phagocyte NAPDH–oxidase complex consists of several phagocyte oxidase (phox) proteins, generating reactive oxygen species (ROS) upon activation. ROS are involved in the defense against microorganisms and also in immune regulation. Defective ROS formation leads to chronic granulomatous disease (CGD) with increased incidence of autoimmunity and disturbed resolution of inflammation. Because regulatory T cells (Tregs) suppress autoimmune T-cell responses and are crucial in down-regulating immune responses, we hypothesized that ROS deficiency may lead to decreased Treg induction. Previously, we showed that in p47phox-mutated mice, reconstitution of macrophages (Mph) with ROS-producing capacity was sufficient to protect the mice from arthritis. Now, we present evidence that Mph-derived ROS induce Tregs. In vitro, we showed that Mph ROS-dependently induce Treg, using an NADPH-oxidase inhibitor. This finding was confirmed genetically: rat or human CGD Mph with mutated p47phox or gp91phox displayed hampered Treg induction and T-cell suppression. However, basal Treg numbers in these subjects were comparable to those in controls, indicating a role for ROS in induction of peripheral Tregs. Induction of allogeneic delayed-type hypersensitivity with p47phox-mutated Mph confirmed the importance of Mph-derived ROS in Treg induction in vivo. We conclude that NAPDH oxidase activity in Mph is important for the induction of Tregs to regulate T cell-mediated inflammation.

Kraaij, Marina D.; Savage, Nigel D. L.; van der Kooij, Sandra W.; Koekkoek, Karin; Wang, Jun; van den Berg, J. Merlijn; Ottenhoff, Tom H. M.; Kuijpers, Taco W.; Holmdahl, Rikard; van Kooten, Cees; Gelderman, Kyra A.

2010-01-01

238

Genotoxicity and reactive oxygen species production induced by magnetite nanoparticles in mammalian cells.  

PubMed

We examined the genotoxicity of magnetite nanoparticles (primary particle size: 10 nm) on human A549 and Chinese hamster ovary (CHO) AA8 cells. Six hours' treatment with the particles dose-dependently increased the frequency of micronuclei (MN) in the A549 and CHO AA8 cells up to 5.2% and 5.0% at a dose of 200 µg/ml (34 µg/cm²), respectively. In A549 cells, treatment with the nano-particles (2 µg/ml) for 1 hr induced H2AX phosphorylation, which is suggestive of DNA double strand breaks (DSB). Treating CHO AA8 cells with 2 µg/ml (0.34 µg/cm²) magnetite for 1 hour resulted in a five times higher frequency of sister chromatid exchange (SCE) than the control level. We detected reactive oxygen species (ROS) in CHO cells treated with the particles. These findings indicate that magnetite nano-particles induce ROS in mammalian cells, leading to the direct or indirect induction of DSB, followed by clastogenic events including MN and SCE. PMID:23719928

Kawanishi, Masanobu; Ogo, Sayaka; Ikemoto, Miho; Totsuka, Yukari; Ishino, Kousuke; Wakabayashi, Keiji; Yagi, Takashi

2013-01-01

239

The effects of in-cloud sulfate production on light-scattering properties of continental aerosol  

SciTech Connect

Model calculations are presented for continental scenarios that demonstrate that the heterogeneity in the chemistry of different size cloud drops can have a significant impact on the amount of sulfate produced in cloud, its size distribution, and the consequent integral light-scattering efficiency of sulfate. The results are contrasted with previous calculations for a marine scenario. 24 refs., 2 figs., 6 tabs.

Po-Fat Yuen; Hegg, D.A.; Larson, T.V. [Univ. of Washington, Seattle, WA (United States)

1994-07-01

240

Effects of short- and medium-term calorie restriction on muscle mitochondrial proton leak and reactive oxygen species production.  

PubMed

Reductions in cellular oxygen consumption (Vo2) and reactive oxygen species (ROS) production have been proposed as mechanisms underlying the anti-aging effects of calorie restriction (CR). Mitochondria are a cell's greatest "sink" for oxygen and also its primary source of ROS. The mitochondrial proton leak pathway is responsible for 20-30% of Vo2 in resting cells. We hypothesized that CR leads to decreased proton leak with consequential decreases in Vo2, ROS production, and cellular damage. Here, we report the effects of short-term (2-wk, 2-mo) and medium-term (6-mo) CR (40%) on rat muscle mitochondrial proton leak, ROS production, and whole animal Vo2. Whole body Vo2 decreased with CR at all time points, whereas mass-adjusted Vo2 was normal until the 6-mo time point, when it was 40% lower in CR compared with control rats. At all time points, maximal leak-dependent Vo2 was lower in CR rats compared with controls. Proton leak kinetics indicated that mechanisms of adaptation to CR were different between short- and medium-term treatments, with the former leading to decreases in protonmotive force (Deltap) and state 4 Vo2 and the latter to increases in Deltap and decreases in state 4 Vo2. Results from metabolic control analyses of oxidative phosphorylation are consistent with the idea that short- and medium-term responses are distinct. Mitochondrial H2O2 production was lower in all three CR groups compared with controls. Overall, this study details the rapid effects of short- and medium-term CR on proton leak, ROS production, and metabolic control of oxidative phosphorylation. Results indicate that a reduction in mitochondrial Vo2 and ROS production may be a mechanism for the actions of CR. PMID:14736705

Bevilacqua, Lisa; Ramsey, Jon J; Hagopian, Kevork; Weindruch, Richard; Harper, Mary-Ellen

2004-01-21

241

The modulation of reactive oxygen species production from human polymorphonuclear cells by curdlan derivatives as dectin-1 agonists/antagonists.  

PubMed

Reactive oxygen species (ROS) are well known to be cytotoxic and have been implicated in the etiology of a wide array of human diseases including diabetes, neurodegenerative diseases, cancer and also influence central cellular processes such as proliferation, apoptosis, senescence etc. If in these pathological or degenerative conditions characterized by free radicals excess, reactive species are not eliminated, they can maintain destructive processes, already initiated at different cellular levels. Understanding the role of ROS as key mediators in signaling cascades may provide various opportunities for pharmacological intervention. Toll-like receptors and C-type lectin receptor class V--Dectin-1, as members of Pattern Recognition Receptors play an essential role in innate immune response against bacteria and fungi respectively, contributing to pathogens recognition, phagocytosis, ROS production and induction of pro-inflammatory cytokines secretion. Using a high performance chemiluminometric method, we studied the action of six Curdlan derivatives on the ROS production and release by activated human polymorphonuclear cells (PMNs) isolated from the peripheral blood of healthy donors. Our results demonstrated that Curdlan derivatives containing sulfopropyl groups did not activate human PMNs to release ROS. These compounds blocked Dectin-1 and were able to inhibit co-operation between Dectin-1 and TLR-2. Curdlan derivatives containing palmithoyl, carboxi-methyl and sulfopropyl groups increased ROS release by human PMNs activated at TLR-2 level. Taking into account the fact that Dectin-1 can actively collaborate with TLR-2 to modulate the subsequent adaptive immune response, we can presume that Curdlan derivatives containing sulfopropyl group or palmithoyl/carboxi-methyl/sulfopropyl groups, as possible Dectin-1 antagonists/agonists, could influence TLR-2 signaling. PMID:20361523

B?dulescu, Maria-Mihaela; Lupu, Andreea-Roxana; Cremer, Lidia; C?lug?ru, Ana; Apetrei, Natalia Simona; Moscovici, M; Mocanu, Georgeta; Szegli, G

242

Flow cytometric measurement of reactive oxygen species production by normal and thalassaemic red blood cells.  

PubMed

Reactive oxygen species (ROS) contribute to the pathogenesis of several hereditary disorders of red blood cells (RBCs), including thalassaemia. We report here on a modified flow cytometric method for measuring ROS in normal and thalassaemic RBCs. RBCs were incubated with 0.4 mM 2',7'-dichlorofluorescin diacetate (DCFH-DA), then washed and further incubated either with or without 2 mM H2O2. Flow cytometric analysis showed that RBC fluorescence increased with time; it increased faster and reached higher intensity (by 10-30-fold) in H2O2-stimulated RBCs as compared to unstimulated RBCs. In both cases, the antioxidant N-acetyl-l-cysteine reduced fluorescence, confirming previous reports that DCFH fluorescence is mediated by ROS. While the fluorescence of unstimulated RBCs increased with time, probably because of exposure to atmospheric oxygen, in H2O2-stimulated RBCs fluorescence decreased after 30 min. The latter effect is most likely related to H2O2 decomposition by catalase as both sodium azide, an antimetabolite that inhibits catalase and low temperature increased the fluorescence of stimulated RBCs. Washing had a similar effect, suggesting that maintenance of the oxidised DCF requires a constant supply of ROS. We next studied RBCs of beta-thalassaemic patients. The results demonstrated a significantly higher ROS generation by stimulated and unstimulated thalassaemic RBCs compared to their normal counterparts. These results suggest that flow cytometry can be useful for measuring the ROS status of RBCs in various diseases and for studying chemical agents as antioxidants. PMID:12581189

Amer, Johnny; Goldfarb, Ada; Fibach, Eitan

2003-02-01

243

The stimulated innate resistance event in Bordetella pertussis infection is dependent on reactive oxygen species production.  

PubMed

The exacerbated induction of innate immune responses in airways can abrogate diverse lung infections by a phenomenon known as stimulated innate resistance (StIR). We recently demonstrated that the enhancement of innate response activation can efficiently impair Bordetella pertussis colonization in a Toll-like receptor 4 (TLR4)-dependent manner. The aim of this work was to further characterize the effect of lipopolysaccharide (LPS) on StIR and to identify the mechanisms that mediate this process. Our results showed that bacterial infection was completely abrogated in treated mice when the LPS of B. pertussis (1 ?g) was added before (48 h or 24 h), after (24 h), or simultaneously with the B. pertussis challenge (10(7) CFU). Moreover, we detected that LPS completely cleared bacterial infection as soon as 2 h posttreatment. This timing suggests that the observed StIR phenomenon should be mediated by fast-acting antimicrobial mechanisms. Although neutrophil recruitment was already evident at this time point, depletion assays using an anti-GR1 antibody showed that B. pertussis clearance was achieved even in the absence of neutrophils. To evaluate the possible role of free radicals in StIR, we performed animal assays using the antioxidant N-acetyl cysteine (NAC), which is known to inactivate oxidant species. NAC administration blocked the B. pertussis clearance induced by LPS. Nitrite concentrations were also increased in the LPS-treated mice; however, the inhibition of nitric oxide synthetases did not suppress the LPS-induced bacterial clearance. Taken together, our results show that reactive oxygen species (ROS) play an essential role in the TLR4-dependent innate clearance of B. pertussis. PMID:23630952

Zurita, E; Moreno, G; Errea, A; Ormazabal, M; Rumbo, M; Hozbor, D

2013-04-29

244

Effect of stationary magnetic field strengths of 150 and 200 mT on reactive oxygen species production in soybean.  

PubMed

Our previous investigation reported the beneficial effect of pre-sowing magnetic treatment for improving germination parameters and biomass accumulation in soybean. In this study, soybean seeds treated with static magnetic fields of 150 and 200 mT for 1 h were evaluated for reactive oxygen species (ROS) and activity of antioxidant enzymes. Superoxide and hydroxyl radicals were measured in embryos and hypocotyls of germinating seeds by electron paramagnetic resonance spectroscopy and kinetics of superoxide production; hydrogen peroxide and antioxidant activities were estimated spectrophotometrically. Magnetic field treatment resulted in enhanced production of ROS mediated by cell wall peroxidase while ascorbic acid content, superoxide dismutase and ascorbate peroxidase activity decreased in the hypocotyl of germinating seeds. An increase in the cytosolic peroxidase activity indicated that this antioxidant enzyme had a vital role in scavenging the increased H(2)O(2) produced in seedlings from the magnetically treated seeds. Hence, these studies contribute to our first report on the biochemical basis of enhanced germination and seedling growth in magnetically treated seeds of soybean in relation to increased production of ROS. PMID:22253132

Shine, M B; Guruprasad, K N; Anand, Anjali

2012-01-17

245

Cell death and production of reactive oxygen species by murine macrophages after short term exposure to phthalates.  

PubMed

The effects of four phthalates, i.e., di-2-ethylhexyl phthalate (DEHP), butyl benzyl phthalate (BBP), dibutyl phthalate (DBP) and diisobutyl phthalate (DIBP) on necrotic and apoptotic cell death, and production of reactive oxygen species (ROS) were studied on mouse macrophage cell line RAW 264.7. All the phthalates caused negligible and non-dose-dependent ROS production compared to control experiment. DEHP and BBP did not cause significant necrotic nor apoptotic cell death at any of the studied doses. Both DIBP and DBP caused dose-dependent necrotic cell death at the two highest concentrations (100 microM and 1 mM). Both doses (500 microM and 1 mM) of DIBP increased apoptosis by 31- and 60-fold, respectively, whereas the increase in apoptotic cell death caused by DBP was only two and fourfold, that however, was not statistically significant. In conclusion, DIBP caused a substantially different apoptotic cell death effect on murine macrophages from the three other phthalates, and this effect was not related to ROS production. Thus, toxicological and health risks of DIBP and DBP should be assessed separately in the future. PMID:19446250

Naarala, J; Korpi, A

2009-04-09

246

Simultaneous production of laccase and decolouration of the diazo dye Reactive Black 5 in a fixed-bed bioreactor.  

PubMed

In this paper the production of laccase and the decolouration of the recalcitrant diazo dye Reactive Black 5 (RB5) by the white-rot fungus Trametes pubescens immobilised on stainless steel sponges in a fixed-bed reactor were studied. Laccase production was increased by 10-fold in the presence of RB5 and reached a maximum value of 1025U/l. Enhanced laccase production in the presence of RB5 in this fungus is an added advantage during biodegradation of RB5-containing effluents. The decolouration of RB5 was due to two processes: dye adsorption onto the fungal mycelium and dye degradation by the laccase enzymes produced by the fungus. RB5 decolouration was performed during four successive batches obtaining high decolouration percentages (74%, 43% and 52% in 24h for the first, third and four batch, respectively) without addition of redox mediators. Also, the in vitro decolouration of RB5 by the concentrated culture extract, containing mainly laccase, produced in the above bioreactor was studied. The decolouration percentages obtained were considerably lower (around 20% in 24h) than that attained with the whole culture. PMID:18845391

Enayatzamir, Kheirghadam; Alikhani, Hossein A; Rodríguez Couto, Susana

2008-08-20

247

A NOVEL CONTINUOUS-FLOW REACTOR USING REACTIVE DISTILLATION FOR BIODIESEL PRODUCTION  

Microsoft Academic Search

The production of biodiesel through batch and existing continuous-flow processes requires the use of a much higher excess alcohol, typically 100%, than the stoichiometric molar requirement in order to drive the transesterification reaction to completion. This excess alcohol must be recovered in a separate process, which involves additional capital and operating costs. In this study, a novel reactor system using

B. B. He; A. P. Singh; J. C. Thompson

248

Role of renal DJ-1 in the pathogenesis of hypertension associated with increased reactive oxygen species production.  

PubMed

The D(2) dopamine receptor (D(2)R) is important in the pathogenesis of essential hypertension. We have already reported that systemic deletion of the D(2)R gene in mice results in reactive oxygen species (ROS)-dependent hypertension, suggesting that the D(2)R has antioxidant effects. However, the mechanism of this effect is unknown. DJ-1 is a protein that has antioxidant properties. D(2)R and DJ-1 are expressed in the mouse kidney and colocalize and coimunoprecipitate in mouse renal proximal tubule cells. We hypothesized that D(2)Rs regulate renal ROS production in the kidney through regulation of DJ-1 expression or function. Heterozygous D(2)(+/-) mice have increased blood pressure, urinary 8-isoprostanes, and renal Nox 4 expression, but decreased renal DJ-1 expression. Silencing D(2)R expression in mouse renal proximal tubule cells increases ROS production and decreases the expression of DJ-1. Conversely, treatment of these cells with a D(2)R agonist increases DJ-1 expression and decreases Nox 4 expression and NADPH oxidase activity, effects that are partially blocked by a D(2)R antagonist. Silencing DJ-1 expression in mouse renal proximal tubule cells increases ROS production and Nox 4 expression. Selective renal DJ-1 silencing by the subcapsular infusion of DJ-1 siRNA in mice increases blood pressure, renal Nox4 expression, and NADPH oxidase activity. These results suggest that the inhibitory effects of D(2)R on renal ROS production are at least, in part, mediated by a positive regulation of DJ-1 expression/function and that DJ-1 may have a role in the prevention of hypertension associated with increased ROS production. PMID:22215708

Cuevas, Santiago; Zhang, Yanrong; Yang, Yu; Escano, Crisanto; Asico, Laureano; Jones, John E; Armando, Ines; Jose, Pedro A

2012-01-03

249

Combination and QCD analysis of charm production cross section measurements in deep-inelastic ep scattering at HERA  

NASA Astrophysics Data System (ADS)

Measurements of open charm production cross sections in deep-inelastic ep scattering at HERA from the H1 and ZEUS Collaborations are combined. Reduced cross sections ?_red^{cbar{c}} for charm production are obtained in the kinematic range of photon virtuality 2.5? Q 2?2000 GeV2 and Bjorken scaling variable 3?10-5? x?5?10-2. The combination method accounts for the correlations of the systematic uncertainties among the different data sets. The combined charm data together with the combined inclusive deep-inelastic scattering cross sections from HERA are used as input for a detailed NLO QCD analysis to study the influence of different heavy flavour schemes on the parton distribution functions. The optimal values of the charm mass as a parameter in these different schemes are obtained. The implications on the NLO predictions for W ± and Z production cross sections at the LHC are investigated. Using the fixed flavour number scheme, the running mass of the charm quark is determined.

Abramowicz, H.; Abt, I.; Adamczyk, L.; Adamus, M.; Aggarwal, R.; Alexa, C.; Andreev, V.; Antonelli, S.; Antonioli, P.; Antonov, A.; Arneodo, M.; Arslan, O.; Aushev, V.; Aushev, Y.; Bachynska, O.; Baghdasaryan, A.; Baghdasaryan, S.; Bamberger, A.; Barakbaev, A. N.; Barbagli, G.; Bari, G.; Barreiro, F.; Bartel, W.; Bartosik, N.; Bartsch, D.; Basile, M.; Begzsuren, K.; Behnke, O.; Behr, J.; Behrens, U.; Bellagamba, L.; Belousov, A.; Belov, P.; Bertolin, A.; Bhadra, S.; Bindi, M.; Blohm, C.; Bokhonov, V.; Bondarenko, K.; Boos, E. G.; Borras, K.; Boscherini, D.; Bot, D.; Boudry, V.; Bozovic-Jelisavcic, I.; Bo?d, T.; Brümmer, N.; Bracinik, J.; Brandt, G.; Brinkmann, M.; Brisson, V.; Britzger, D.; Brock, I.; Brownson, E.; Brugnera, R.; Bruni, A.; Bruni, G.; Brzozowska, B.; Bunyatyan, A.; Bussey, P. J.; Bylinkin, A.; Bylsma, B.; Bystritskaya, L.; Caldwell, A.; Campbell, A. J.; Cantun Avila, K. B.; Capua, M.; Carlin, R.; Catterall, C. D.; Ceccopieri, F.; Cerny, K.; Chekanov, S.; Chekelian, V.; Chwastowski, J.; Ciborowski, J.; Ciesielski, R.; Cifarelli, L.; Cindolo, F.; Contin, A.; Contreras, J. G.; Cooper-Sarkar, A. M.; Coppola, N.; Corradi, M.; Corriveau, F.; Costa, M.; Cvach, J.; D'Agostini, G.; Dainton, J. B.; Dal Corso, F.; Daum, K.; Delvax, J.; Dementiev, R. K.; Derrick, M.; Devenish, R. C. E.; De Pasquale, S.; De Wolf, E. A.; del Peso, J.; Diaconu, C.; Dobre, M.; Dobur, D.; Dodonov, V.; Dolgoshein, B. A.; Dolinska, G.; Dossanov, A.; Doyle, A. T.; Drugakov, V.; Durkin, L. S.; Dusini, S.; Eckerlin, G.; Egli, S.; Eisenberg, Y.; Elsen, E.; Ermolov, P. F.; Eskreys, A.; Fang, S.; Favart, L.; Fazio, S.; Fedotov, A.; Felst, R.; Feltesse, J.; Ferencei, J.; Ferrando, J.; Ferrero, M. I.; Figiel, J.; Fischer, D.-J.; Fleischer, M.; Fomenko, A.; Foster, B.; Gabathuler, E.; Gach, G.; Galas, A.; Gallo, E.; Garfagnini, A.; Gayler, J.; Geiser, A.; Ghazaryan, S.; Gialas, I.; Gizhko, A.; Gladilin, L. K.; Gladkov, D.; Glasman, C.; Glazov, A.; Goerlich, L.; Gogitidze, N.; Gogota, O.; Golubkov, Y. A.; Göttlicher, P.; Gouzevitch, M.; Grab, C.; Grabowska-Bo?d, I.; Grebenyuk, A.; Grebenyuk, J.; Greenshaw, T.; Gregor, I.; Grigorescu, G.; Grindhammer, G.; Grzelak, G.; Gueta, O.; Guzik, M.; Gwenlan, C.; Hüttmann, A.; Haas, T.; Habib, S.; Haidt, D.; Hain, W.; Hamatsu, R.; Hart, J. C.; Hartmann, H.; Hartner, G.; Henderson, R. C. W.; Hennekemper, E.; Henschel, H.; Herbst, M.; Herrera, G.; Hildebrandt, M.; Hilger, E.; Hiller, K. H.; Hladký, J.; Hochman, D.; Hoffmann, D.; Hori, R.; Horisberger, R.; Hreus, T.; Huber, F.; Ibrahim, Z. A.; Iga, Y.; Ingbir, R.; Ishitsuka, M.; Jacquet, M.; Jakob, H.-P.; Janssen, X.; Januschek, F.; Jones, T. W.; Jönsson, L.; Jüngst, M.; Jung, A. W.; Jung, H.; Kadenko, I.; Kahle, B.; Kananov, S.; Kanno, T.; Kapichine, M.; Karshon, U.; Karstens, F.; Katkov, I. I.; Kaur, P.; Kaur, M.; Kenyon, I. R.; Keramidas, A.; Khein, L. A.; Kiesling, C.; Kim, J. Y.; Kisielewska, D.; Kitamura, S.; Klanner, R.; Klein, M.; Klein, U.; Kleinwort, C.; Kötz, U.; Koffeman, E.; Kogler, R.; Kondrashova, N.; Kononenko, O.; Kooijman, P.; Korol, I.; Korzhavina, I. A.; Kostka, P.; Kota?ski, A.; Kowalski, H.; Krämer, M.; Kretzschmar, J.; Krüger, K.; Kuprash, O.; Kuze, M.; Landon, M. P. J.; Lange, W.; Laštovi?ka-Medin, G.; Laycock, P.; Lebedev, A.; Lee, A.; Lendermann, V.; Levchenko, B. B.; Levonian, S.; Levy, A.; Libov, V.; Limentani, S.; Ling, T. Y.; Lipka, K.; Lisovyi, M.; List, B.; List, J.; Lobodzinska, E.; Lobodzinski, B.; Löhr, B.; Lohmann, W.; Lohrmann, E.; Long, K. R.; Longhin, A.; Lontkovskyi, D.; Lopez-Fernandez, R.; Lubimov, V.; Lukina, O. Y.; Maeda, J.; Magill, S.; Makarenko, I.; Malinovski, E.; Malka, J.; Mankel, R.; Margotti, A.; Marini, G.; Martin, J. F.; Martyn, H.-U.; Mastroberardino, A.; Mattingly, M. C. K.; Maxfield, S. J.; Mehta, A.; Melzer-Pellmann, I.-A.; Mergelmeyer, S.; Meyer, A. B.; Meyer, H.; Meyer, J.; Miglioranzi, S.; Mikocki, S.; Milcewicz-Mika, I.; Mohamad Idris, F.; Monaco, V.; Montanari, A.; Moreau, F.; Morozov, A.; Morris, J. V.; Morris, J. D.; Mujkic, K.; Müller, K.; Musgrave, B.; Nagano, K.; Namsoo, T.; Nania, R.; Naumann, T.; Newman, P. R.; Niebuhr, C.; Nigro, A.; Nikitin, D.; Ning, Y.; Nobe, T.; Notz, D.; Nowak, G.; Nowak, K.; Nowak, R. J.; Nuncio-Quiroz, A. E.; Oh, B. Y.; Okazaki, N.; Olkiewicz, K.; Olsson, J. E.; Onishchuk, Y.; Ozerov, D.; Pahl, P.; Palichik, V.; Pandurovic, M.; Papageorgiu, K.; Parenti, A.; Pascaud, C.; Patel, G. D.; Paul, E.; Pawlak, J. M.; Pawlik, B.; Pelfer, P. G.; Pellegrino, A.; Perez, E.; Perla?ski, W.; Perrey, H.; Petrukhin, A.; Picuric, I.; Piotrzkowski, K.; Pirumov, H.; Pitzl, D.; Pla?akyt?, R.; Pluci?ski, P.; Pokorny, B.; Pokrovskiy, N. S.; Polifka, R.; Polini, A.; Povh, B.; Proskuryakov, A. S.; Przybycie?, M.; Radescu, V.; Raicevic, N.; Raval, A.

2013-02-01

250

Synthesis and aqueous chemistry of alpha-acetoxy-N-nitrosomorpholine: reactive intermediates and products.  

PubMed

[reaction: see text] Alpha-acetoxy-N-nitrosomorpholine (7) has been synthesized starting by the anodic oxidation of N-acetylmorpholine in methanol. The 55% yield of N-nitrosomorpholinic acid, after cyanide-for-methoxy group exchange and hydrolysis, is an improvement of approximately 10-fold over our original 10-step method, and this is readily converted to 7. A study of the kinetics of decomposition of 7 in aqueous media at 25 degrees C and 1 M ionic strength was conducted over the pH range from 1 to 12. The reaction exhibited good first-order kinetics at all values of pH, and a plot of the log of k0, the buffer-independent rate constant for decomposition, against pH indicated that a pH-independent reaction dominates in the neutral pH region whereas acid- and base-catalyzed reactions dominate in the low and high pH regions, respectively. Reaction at neutral pH in the presence of increasing concentrations of acetate ion results in a decrease in the value of k(obsd), to an apparent limiting value consistent with a common-ion inhibition by the capture, and competing base-catalyzed hydration of, an N-nitrosiminium ion intermediate. The 100-fold smaller reactivity of 7 at neutral pH compared with its carbon analogue, alpha-acetoxy-N-nitrosopiperidine, is also consistent with the electronic effects expected for such a reaction. The dinitrophenylhydrazones derived from pH-independent and acid-catalyzed reactions are identical in kind and quantity, within experimental error, to those observed in the decay of alpha-hydroxy-N-nitrosomorpholine. Decay of 7 in the presence of benzimidazole buffer results in the formation of 2-(2-(1H-benzo[d]imidazol-1-yl)ethoxy)acetaldehyde (12) and 2-(1H-benzo[d]imidazol-1-yl)ethanol (13). Independent synthesis and study of 12 indicates that it is stable at 80 degrees C in 0.1 M DCl, but it slowly decomposes to 13 in neutral and basic media in a reaction that is stimulated by primary and secondary amines, but not by tertiary amines and carbonate buffer. The benzimidazole trapping studies and those of the stability of 12 indicate the possibility that metabolic activation of N-nitrosomorpholine by hydroxylation alpha to the nitroso nitrogen can result in the deposition of a metastable ethoxyacetaldehyde adduct on the heteroatoms of DNA. PMID:16388636

Zink, Charles N; Kim, Hyun-Joong; Fishbein, James C

2006-01-01

251

Interactions of corrosion products and bentonite: An extended multicomponent reactive transport model  

Microsoft Academic Search

Radioactive waste disposal in deep geological repositories envisages various engineered barriers such as carbon–steel canisters and compacted bentonite. Canister corrosion and the chemical interactions of corrosion products with bentonite are key reactions for the long term performance of a repository. Samper, Lu, and Montenegro (Physics and Chemistry of the Earth 2008; 33S: S306-S316) reported numerical models to simulate canister corrosion

Chuanhe Lu; Javier Samper; Bertrand Fritz; Alain Clement; Luis Montenegro

252

Measurement of dijet production in diffractive deep-inelastic scattering with a leading proton at HERA  

NASA Astrophysics Data System (ADS)

The cross section of diffractive deep-inelastic scattering ep? eXp is measured, where the system X contains at least two jets and the leading final state proton is detected in the H1 Forward Proton Spectrometer. The measurement is performed for fractional proton longitudinal momentum loss x ?<0.1 and covers the range 0.1<| t|<0.7 GeV2 in squared four-momentum transfer at the proton vertex and 4< Q 2<110 GeV2 in photon virtuality. The differential cross sections extrapolated to | t|<1 GeV2 are in agreement with next-to-leading order QCD predictions based on diffractive parton distribution functions extracted from measurements of inclusive and dijet cross sections in diffractive deep-inelastic scattering. The data are also compared with leading order Monte Carlo models.

Aaron, F. D.; Alexa, C.; Andreev, V.; Backovic, S.; Baghdasaryan, A.; Baghdasaryan, S.; Barrelet, E.; Bartel, W.; Begzsuren, K.; Belousov, A.; Belov, P.; Bizot, J. C.; Boudry, V.; Bozovic-Jelisavcic, I.; Bracinik, J.; Brandt, G.; Brinkmann, M.; Brisson, V.; Britzger, D.; Bruncko, D.; Bunyatyan, A.; Buschhorn, G.; Bystritskaya, L.; Campbell, A. J.; Cantun Avila, K. B.; Ceccopieri, F.; Cerny, K.; Cerny, V.; Chekelian, V.; Contreras, J. G.; Coughlan, J. A.; Cvach, J.; Dainton, J. B.; Daum, K.; Delcourt, B.; Delvax, J.; De Wolf, E. A.; Diaconu, C.; Dobre, M.; Dodonov, V.; Dossanov, A.; Dubak, A.; Eckerlin, G.; Egli, S.; Eliseev, A.; Elsen, E.; Favart, L.; Fedotov, A.; Felst, R.; Feltesse, J.; Ferencei, J.; Fischer, D.-J.; Fleischer, M.; Fomenko, A.; Gabathuler, E.; Gayler, J.; Ghazaryan, S.; Glazov, A.; Goerlich, L.; Gogitidze, N.; Gouzevitch, M.; Grab, C.; Grebenyuk, A.; Greenshaw, T.; Grell, B. R.; Grindhammer, G.; Habib, S.; Haidt, D.; Helebrant, C.; Henderson, R. C. W.; Hennekemper, E.; Henschel, H.; Herbst, M.; Herrera, G.; Hildebrandt, M.; Hiller, K. H.; Hoffmann, D.; Horisberger, R.; Hreus, T.; Huber, F.; Jacquet, M.; Janssen, X.; Jönsson, L.; Jung, H.; Kapichine, M.; Kenyon, I. R.; Kiesling, C.; Klein, M.; Kleinwort, C.; Kluge, T.; Kogler, R.; Kostka, P.; Kraemer, M.; Kretzschmar, J.; Krüger, K.; Landon, M. P. J.; Lange, W.; Laštovi?ka-Medin, G.; Laycock, P.; Lebedev, A.; Lendermann, V.; Levonian, S.; Lipka, K.; List, B.; List, J.; Lopez-Fernandez, R.; Lubimov, V.; Makankine, A.; Malinovski, E.; Marage, P.; Martyn, H.-U.; Maxfield, S. J.; Mehta, A.; Meyer, A. B.; Meyer, H.; Meyer, J.; Mikocki, S.; Milcewicz-Mika, I.; Moreau, F.; Morozov, A.; Morris, J. V.; Mudrinic, M.; Müller, K.; Naumann, Th.; Newman, P. R.; Niebuhr, C.; Nikitin, D.; Nowak, G.; Nowak, K.; Olsson, J. E.; Ozerov, D.; Pahl, P.; Palichik, V.; Panagoulias, I.; Pandurovic, M.; Papadopoulou, Th.; Pascaud, C.; Patel, G. D.; Perez, E.; Petrukhin, A.; Picuric, I.; Piec, S.; Pirumov, H.; Pitzl, D.; Pla?akyt?, R.; Pokorny, B.; Polifka, R.; Povh, B.; Radescu, V.; Raicevic, N.; Ravdandorj, T.; Reimer, P.; Rizvi, E.; Robmann, P.; Roosen, R.; Rostovtsev, A.; Rotaru, M.; Ruiz Tabasco, J. E.; Rusakov, S.; Šálek, D.; Sankey, D. P. C.; Sauter, M.; Sauvan, E.; Schmitt, S.; Schoeffel, L.; Schöning, A.; Schultz-Coulon, H.-C.; Sefkow, F.; Shtarkov, L. N.; Shushkevich, S.; Sloan, T.; Smiljanic, I.; Soloviev, Y.; Sopicki, P.; South, D.; Spaskov, V.; Specka, A.; Staykova, Z.; Steder, M.; Stella, B.; Stoicea, G.; Straumann, U.; Sykora, T.; Thompson, P. D.; Tran, T. H.; Traynor, D.; Truöl, P.; Tsakov, I.; Tseepeldorj, B.; Turnau, J.; Valkárová, A.; Vallée, C.; Van Mechelen, P.; Vazdik, Y.; Wegener, D.; Wünsch, E.; Žá?ek, J.; Zálešák, J.; Zhang, Z.; Zhokin, A.; Zohrabyan, H.; Zomer, F.

2012-04-01

253

Limits on Production of Narrow Band Photons from Inverse Compton Scattering  

SciTech Connect

In using the inverse Compton scattering (ICS) interaction as a high brilliance, short wavelength radiation source, one collides two beams, one an intense laser, and the other a high charge, short pulse electron beam. In order to maximize the flux of photons from ICS, one must focus both beams strongly, which implies both use of short beams and the existence of large angles in the interaction. One aspect of brilliance is the narrowness of the wavelength band emitted by the source. This paper explores the limits of ICS-based source brilliance based on inherent wavelength broadening effects that arise due to focal angles, laser energy density, and finite laser pulse length effects. It is shown that for a nominal 1% desired bandwidth, that one obtains approximately one scattered photon per electron in a head-on collision geometry.

Rosenzweig, J.; Williams, O. [UCLA Dept. of Physics and Astronomy, 405 Hilgard Ave., Los Angeles, CA 90034 (United States)

2006-11-27

254

Quantification of microbial productivity via multi-angle light scattering and supervised learning.  

PubMed

This article describes the use of chemometric methods for prediction of biological parameters of cell suspensions on the basis of their light scattering profiles. Laser light is directed into a vial or flow cell containing media from the suspension. The intensity of the scattered light is recorded at 18 angles. Supervised learning methods are then used to calibrate a model relating the parameter of interest to the intensity values. Using such models opens up the possibility of estimating the biological properties of fermentor broths extremely rapidly (typically every 4 sec), and, using the flow cell, without user interaction. Our work has demonstrated the usefulness of this approach for estimation of yeast cell counts over a wide range of values (10(5)-10(9) cells mL-1), although it was less successful in predicting cell viability in such suspensions. PMID:10099324

Jones, A; Young, D; Taylor, J; Kell, D B; Rowland, J J

1998-07-20

255

Secondary reactive oxygen species production after PDT during pulmonary tumor growth in sera of nude mice.  

PubMed

Photodynamic therapy (PDT), mediated by a sensitizer exposed to light to produce singlet oxygen ((1)O2), induces tumor responses varying from one person to another. Cancer growth induces oxidative stress at any step of its development from induction to treatment, which could also modify response to PDT. After the initial amount of (1)O2 delivered, secondary oxidative species (SOS) are also generated inducing additional damages. Using an in vitro assay we saw variations among mice strains concerning their serum capability to generate SOS after (1)O2 production. Nude mice had a higher capability to generate SOS as compared to the non mutated strain. Capability to generate SOS evolved during growth of orthotopically-grafted pulmonary cancers (A549), with either values corrected for hemolysis or not. Immediately after graft SOS production decreased, then increased again, reaching a plateau phase after 10 days which lasted for 20 days and finally increased steeply during the last phase of tumor growth, preceding cachexia and death. This profile differed profoundly from the one observed after heterotopic tumor grafts for which hemolysis induced artifacts masking important variations in SOS production. Our results demonstrate experimentally a relationship between the general health status of an individual, cancer progression and serum capability to generate SOS during PDT. These findings could explain some PDT failures as well as some unexpected successes on large tumors and should be taken into account when determining treatment parameters. They may also explain why different effects are observed on different experimental models with similar sensitizers. PMID:23465374

Douillard, Samuel; Rozec, Bertrand; Bigot, Edith; Aillet, Lorena; Patrice, Thierry

2012-06-27

256

Reactive processing of polymers: Structural characterisation of products by 1H and 13C NMR spectroscopy for glycidyl methacrylate grafting onto EPR in the absence and presence of a reactive comonomer  

Microsoft Academic Search

Grafted GMA on EPR samples were prepared in a Thermo-Haake internal mixer by free radical melt grafting reactions in the absence (conventional system; EPR–g–GMACONV) and presence of the reactive comonomer divinyl benzene, DVB (EPR–g–GMADVB). The GMA-homopolymer (poly-GMA), a major side reaction product in the conventional system, was almost completely absent in the DVB-containing system, the latter also resulted in a

K. Doudin; A. Ahmad; S. Al-Malaika

2009-01-01

257

Rapid and reactive nitric oxide production by astrocytes in mouse neocortical slices  

Microsoft Academic Search

ABSTRACT Nitric oxide (NO), a cellular signaling molecule, is produced in the brain,by both neurons,and,astrocytes. While neurons are capable,of rapid release of small,amounts,of NO serving as neurotransmitter, astrocytic NO production has been demonstrated,mainly,as a slow,reaction,to various,stress stimuli. Little is known,about,the,role,of astrocyte-pro- duced NO. Using the NO indicator 4,5-diaminofluorescein-2 diacetate (DAF-2DA) and acute slices from mouse brain, we distinguished,neurons,from,astrocytes,based,on their differ-

Yossi Buskila; Shai Farkash; Michal Hershfinkel; Yael Amitai

2005-01-01

258

Rapid and reactive nitric oxide production by astrocytes in mouse neocortical slices.  

PubMed

Nitric oxide (NO), a cellular signaling molecule, is produced in the brain by both neurons and astrocytes. While neurons are capable of rapid release of small amounts of NO serving as neurotransmitter, astrocytic NO production has been demonstrated mainly as a slow reaction to various stress stimuli. Little is known about the role of astrocyte-produced NO. Using the NO indicator 4,5-diaminofluorescein-2 diacetate (DAF-2DA) and acute slices from mouse brain, we distinguished neurons from astrocytes based on their different fluorescence kinetics and pattern, cellular morphology, electrophysiology, and responses to selective nitric oxide synthase (NOS) inhibitors. Typically, astrocytic fluorescence followed neuronal fluorescence with a delay of 1-2 min and was dependent on the inducible NOS isoform (iNOS) activity. Western blot analysis established the presence of functional iNOS in the neocortex. An assay for cell death revealed that most DAF-2DA-positive neurons, but not astrocytes, were damaged. Whole cell recordings from astrocytes confirmed that these cells maintained their membrane potential and passive properties during illumination and afterward. Induction of excitotoxicity by brief application of glutamate triggered an immediate and intense astrocytic response, while high-frequency electrical stimulation failed to do so. The present study demonstrates, for the first time, rapid and massive iNOS-dependent NO production by astrocytes in situ, which appears to be triggered by acute neuronal death. These data may bear important implications for our theoretical understanding and practical management of acute brain insults. PMID:15968628

Buskila, Yossi; Farkash, Shai; Hershfinkel, Michal; Amitai, Yael

2005-11-15

259

A NAC transcription factor NTL4 promotes reactive oxygen species production during drought-induced leaf senescence in Arabidopsis.  

PubMed

Reactive oxygen species (ROS) are produced in plant cells primarily as by-products of aerobic energy metabolism. They are also generated during plant adaptation responses to environmental stresses, such as drought and high salinity. Therefore, plants have evolved ROS-detoxifying enzymes and antioxidants to cope with ROS accumulation. However, if stress conditions are prolonged, the level of ROS will surpass the capacity of the detoxifying machinery, causing oxidative damage to cellular constituents. It is known that ROS act in abscisic acid-mediated stress responses to sustain plant survival under adverse growth conditions. However, it is largely unknown how ROS metabolism is linked to stress responses. Here, we show that a drought-responsive NAC transcription factor NTL4 promotes ROS production by binding directly to the promoters of genes encoding ROS biosynthetic enzymes during drought-induced leaf senescence. Leaf senescence was accelerated in 35S:4?C transgenic plants over-expressing an active form of NTL4 under drought conditions. The 35S:4?C transgenic plants were hypersensitive to drought, and ROS accumulated in the leaves. In contrast, ROS levels were reduced in NTL4-deficient ntl4 mutants, which exhibited delayed leaf senescence and enhanced drought resistance. These observations indicate that NTL4 acts as a molecular switch that couples ROS metabolism to drought-induced leaf senescence in Arabidopsis. PMID:22313226

Lee, Sangmin; Seo, Pil Joon; Lee, Hyo-Jun; Park, Chung-Mo

2012-03-31

260

The Neuromediator Glutamate, through Specific Substrate Interactions, Enhances Mitochondrial ATP Production and Reactive Oxygen Species Generation in Nonsynaptic Brain Mitochondria*  

PubMed Central

The finding that upon neuronal activation glutamate is transported postsynaptically from synaptic clefts and increased lactate availability for neurons suggest that brain mitochondria (BM) utilize a mixture of substrates, namely pyruvate, glutamate, and the tricarboxylic acid cycle metabolites. We studied how glutamate affected oxidative phosphorylation and reactive oxygen species (ROS) production in rat BM oxidizing pyruvate + malate or succinate. Simultaneous oxidation of glutamate + pyruvate + malate increased state 3 and uncoupled respiration by 52 and 71%, respectively. The state 4 ROS generation increased 100% over BM oxidizing pyruvate + malate and 900% over that of BM oxidizing glutamate + malate. Up to 70% of ROS generation was associated with reverse electron transport. These effects of pyruvate + glutamate + malate were observed only with BM and not with liver or heart mitochondria. The effects of glutamate + pyruvate on succinate-supported respiration and ROS generation were not organ-specific and depended only on whether mitochondria were isolated with or without bovine serum albumin. With the non-bovine serum albumin brain and heart mitochondria oxidizing succinate, the addition of pyruvate and glutamate abrogated inhibition of Complex II by oxaloacetate. We conclude that (i) during neuronal activation, simultaneous oxidation of glutamate + pyruvate temporarily enhances neuronal mitochondrial ATP production, and (ii) intrinsic inhibition of Complex II by oxaloacetate is an inherent mechanism that protects against ROS generation during reverse electron transport.

Panov, Alexander; Schonfeld, Peter; Dikalov, Sergey; Hemendinger, Richelle; Bonkovsky, Herbert L.; Brooks, Benjamin Rix

2009-01-01

261

Perfluorooctane sulfonate (PFOS) induces reactive oxygen species (ROS) production in human microvascular endothelial cells: role in endothelial permeability  

PubMed Central

Perfluorooctane sulfonate (PFOS) is a member of perfluoroalkyl acids (PFAA) containing an 8-carbon backbone. PFOS is a man-made chemical with carbon-fluorine bonds that are one of the strongest in organic chemistry and widely used in industry. Human occupational and environmental exposure to PFOS occurs globally. PFOS is non-biodegradable and persistent in the human body and environment. In this study, data demonstrated that exposure of human microvascular endothelial cells (HMVEC) to PFOS induced the production of reactive oxygen species (ROS) at both high and low concentrations. Morphologically, it was found that exposure to PFOS induced actin filament remodeling and endothelial permeability changes in HMVEC. Furthermore, data demonstrated the production of ROS plays a regulatory role in PFOS-induced actin filament remodeling and the increase in endothelial permeability. Our results indicate that the generation of ROS may play a role in PFOS-induced aberrations of the endothelial permeability barrier. The results generated from this study may provide a new insight into the potential adverse effects of PFOS exposure on humans at the cellular level.

Qian, Yong; Ducatman, Alan; Ward, Rebecca; Leonard, Steve; Bukowski, Valerie; Guo, Nancy Lan; Shi, Xianglin; Vallyathan, Val; Castranova, Vincent

2011-01-01

262

The Effects of New Alibernet Red Wine Extract on Nitric Oxide and Reactive Oxygen Species Production in Spontaneously Hypertensive Rats  

PubMed Central

We aimed to perform a chemical analysis of both Alibernet red wine and an alcohol-free Alibernet red wine extract (AWE) and to investigate the effects of AWE on nitric oxide and reactive oxygen species production as well as blood pressure development in normotensive Wistar Kyoto (WKY) and spontaneously hypertensive rats (SHRs). Total antioxidant capacity together with total phenolic and selected mineral content was measured in wine and AWE. Young 6-week-old male WKY and SHR were treated with AWE (24,2?mg/kg/day) for 3 weeks. Total NOS and SOD activities, eNOS and SOD1 protein expressions, and superoxide production were determined in the tissues. Both antioxidant capacity and phenolic content were significantly higher in AWE compared to wine. The AWE increased NOS activity in the left ventricle, aorta, and kidney of SHR, while it did not change NOS activity in WKY rats. Similarly, increased SOD activity in the plasma and left ventricle was observed in SHR only. There were no changes in eNOS and SOD1 expressions. In conclusion, phenolics and minerals included in AWE may contribute directly to increased NOS and SOD activities of SHR. Nevertheless, 3 weeks of AWE treatment failed to affect blood pressure of SHR.

Kondrashov, Alexey; Vrankova, Stanislava; Dovinova, Ima; Sevcik, Rudolf; Parohova, Jana; Barta, Andrej; Pechanova, Olga; Kovacsova, Maria

2012-01-01

263

Production mechanism and reactivity of the SiH radical in a silane plasma  

NASA Astrophysics Data System (ADS)

SiH free radicals in a dc multipole post-discharge plasma were analyzed using laser-induced fluorescence. The cross section for SiH formation from 40-70 eV electron impact induced dissociation of SiH 4 was measured to be (10 ± 5) × 10 -17 cm 2. At the instant of its formation in its X 2? ground state, the rotational temperature of the SiH radical is 950 K. This temperature subsequently relaxes by collisions with SiH at a collisional relaxation rate k = (9 ± 2) × 10 13 cm 3/mole s. Quenching of the A 2? electronic state of SiH was found to be negligible below 0.3 Torr. The primary reaction path for destruction of the SiH radical was observed to be via: SiH + SiH 4 ? products, k = 2 × 10 12 cm 3/mole s.

Schmitt, J. P. M.; Gressier, P.; Krishnan, M.; de Rosny, G.; Perrin, J.

1984-02-01

264

A Structural Determinant of Chemical Reactivity and Potential Health Effects of Quinones from Natural Products  

PubMed Central

Although many phenols and catechols found as polyphenol natural products are antioxidants and have putative disease-preventive properties, others have deleterious health effects. One possible route to toxicity is the bioactivation of the phenolic function to quinones that are electrophilic, redox-agents capable of modifying DNA and proteins. The structure-property relationships of biologically important quinones and their precursors may help understand the balance between their health benefits and risks. We describe a mass-spectrometry-based study of four quinones produced by oxidizing flavanones and flavones. Those with a C2-C3 double bond on ring C of the flavonoid stabilize by delocalization an incipient positive charge from protonation and render the protonated quinone particularly susceptible to nucleophilic attack. We hypothesize that the absence of this double bond is one specific structural determinant that is responsible for the ability of quinones to modify biological macromolecules. Those quinones containing a C2-C3 single bond have relative higher aqueous stability and longer half-lives than those with a double bond at the same position; the latter have short half-lives at or below ~ 1 s. Quinones with a C2-C3 double bond show little ability to depurinate DNA because they are rapidly hydrated to unreactive species. Molecular-orbital calculations support that quinone hydration by a highly structure-dependent mechanism accounts for their chemical properties. The evidence taken together support a hypothesis that those flavonoids and related natural products that undergo oxidation to quinones and are then rapidly hydrated are unlikely to damage important biological macromolecules.

Tu, Tingting; Giblin, Daryl; Gross, Michael L.

2011-01-01

265

Search for the single production of doubly-charged Higgs bosons and constraints on their couplings from Bhabha scattering  

NASA Astrophysics Data System (ADS)

A search for the single production of doubly-charged Higgs bosons is performed using e+e- collision data collected by the OPAL experiment at centre-of-mass energies between 189 GeV and 209 GeV. No evidence for the existence of H+/-+/- is observed. Upper limits are derived on hee, the Yukawa coupling of the H+/-+/- to like-signed electron pairs. A 95% confidence level upper limit of hee< 0.071 is inferred for M(H+/-+/-)<160 GeV assuming that the sum of the branching fractions of the H+/-+/- to all lepton flavour combinations is 100%. Additionally, indirect constraints on hee from Bhabha scattering at centre-of-mass energies between 183 GeV and 209 GeV, where the H+/-+/- would contribute via t-channel exchange, are derived for M(H+/-+/-)<2 TeV. These are the first results both from a single production search and on constraints from Bhabha scattering reported from LEP.

Abbiendi, G.; Ainsley, C.; Åkesson, P. F.; Alexander, G.; Allison, J.; Amaral, P.; Anagnostou, G.; Anderson, K. J.; Arcelli, S.; Asai, S.; Axen, D.; Azuelos, G.; Bailey, I.; Barberio, E.; Barlow, R. J.; Batley, R. J.; Bechtle, P.; Behnke, T.; Bell, K. W.; Bell, P. J.; Bella, G.; Bellerive, A.; Benelli, G.; Bethke, S.; Biebel, O.; Boeriu, O.; Bock, P.; Boutemeur, M.; Braibant, S.; Brigliadori, L.; Brown, R. M.; Buesser, K.; Burckhart, H. J.; Campana, S.; Carnegie, R. K.; Caron, B.; Carter, A. A.; Carter, J. R.; Chang, C. Y.; Charlton, D. G.; Csilling, A.; Cuffiani, M.; Dado, S.; de Roeck, A.; de Wolf, E. A.; Desch, K.; Dienes, B.; Donkers, M.; Dubbert, J.; Duchovni, E.; Duckeck, G.; Duerdoth, I. P.; Etzion, E.; Fabbri, F.; Feld, L.; Ferrari, P.; Fiedler, F.; Fleck, I.; Ford, M.; Frey, A.; Fürtjes, A.; Gagnon, P.; Gary, J. W.; Gaycken, G.; Geich-Gimbel, C.; Giacomelli, G.; Giacomelli, P.; Giunta, M.; Goldberg, J.; Groll, M.; Gross, E.; Grunhaus, J.; Gruwé, M.; Günther, P. O.; Gupta, A.; Hajdu, C.; Hamann, M.; Hanson, G. G.; Harder, K.; Harel, A.; Harin-Dirac, M.; Hauschild, M.; Hawkes, C. M.; Hawkings, R.; Hemingway, R. J.; Hensel, C.; Herten, G.; Heuer, R. D.; Hill, J. C.; Hoffman, K.; Horváth, D.; Igo-Kemenes, P.; Ishii, K.; Jeremie, H.; Jovanovic, P.; Junk, T. R.; Kanaya, N.; Kanzaki, J.; Karapetian, G.; Karlen, D.; Kawagoe, K.; Kawamoto, T.; Keeler, R. K.; Kellogg, R. G.; Kennedy, B. W.; Kim, D. H.; Klein, K.; Klier, A.; Kluth, S.; Kobayashi, T.; Kobel, M.; Komamiya, S.; Kormos, L.; Krämer, T.; Krieger, P.; von Krogh, J.; Kruger, K.; Kuhl, T.; Kupper, M.; Lafferty, G. D.; Landsman, H.; Lanske, D.; Layter, J. G.; Leins, A.; Lellouch, D.; Letts, J.; Levinson, L.; Lillich, J.; Lloyd, S. L.; Loebinger, F. K.; Lu, J.; Ludwig, J.; MacPherson, A.; Mader, W.; Marcellini, S.; Martin, A. J.; Masetti, G.; Mashimo, T.; Mättig, P.; McDonald, W. J.; McKenna, J.; McMahon, T. J.; McPherson, R. A.; Meijers, F.; Menges, W.; Merritt, F. S.; Mes, H.; Michelini, A.; Mihara, S.; Mikenberg, G.; Miller, D. J.; Moed, S.; Mohr, W.; Mori, T.; Mutter, A.; Nagai, K.; Nakamura, I.; Nanjo, H.; Neal, H. A.; Nisius, R.; O'Neale, S. W.; Oh, A.; Okpara, A.; Oreglia, M. J.; Orito, S.; Pahl, C.; Pásztor, G.; Pater, J. R.; Patrick, G. N.; Pilcher, J. E.; Pinfold, J.; Plane, D. E.; Poli, B.; Polok, J.; Pooth, O.; Przybycie?, M.; Quadt, A.; Rabbertz, K.; Rembser, C.; Renkel, P.; Roney, J. M.; Rosati, S.; Rozen, Y.; Runge, K.; Sachs, K.; Saeki, T.; Sarkisyan, E. K. G.; Schaile, A. D.; Schaile, O.; Scharff-Hansen, P.; Schieck, J.; Schörner-Sadenius, T.; Schröder, M.; Schumacher, M.; Schwick, C.; Scott, W. G.; Seuster, R.; Shears, T. G.; Shen, B. C.; Sherwood, P.; Siroli, G.; Skuja, A.; Smith, A. M.; Sobie, R.; Söldner-Rembold, S.; Spano, F.; Stahl, A.; Stephens, K.; Strom, D.; Ströhmer, R.; Tarem, S.; Tasevsky, M.; Taylor, R. J.; Teuscher, R.; Thomson, M. A.; Torrence, E.; Toya, D.; Tran, P.; Trigger, I.; Trócsányi, Z.; Tsur, E.; Turner-Watson, M. F.; Ueda, I.; Ujvári, B.; Vollmer, C. F.; Vannerem, P.; Vértesi, R.; Verzocchi, M.; Voss, H.; Vossebeld, J.; Waller, D.; Ward, C. P.; Ward, D. R.; Watkins, P. M.; Watson, A. T.; Watson, N. K.; Wells, P. S.; Wengler, T.; Wermes, N.; Wetterling, D.; Wilson, G. W.; Wilson, J. A.; Wolf, G.; Wyatt, T. R.; Yamashita, S.; Zer-Zion, D.; Zivkovic, L.

2003-12-01

266

The activation of protein kinase C induces higher production of reactive oxygen species by mononuclear cells in patients with multiple sclerosis than in controls  

Microsoft Academic Search

Objective: Recent findings have increasingly shown the importance of reactive oxygen species (ROS) in causing oxidative damage to macromolecules and in contributing to tissue degeneration in target organs of autoimmune diseases. This study was aimed at comparing the base line and induced production of ROS by peripheral blood mononuclear cells (PB MNCs) of patients with multiple sclerosis (MS) in remission

O. Vladimirova; F. M. Lu; L. Shawver; B. Kalman

1999-01-01

267

Catalase Activity and Thiobarbituric Acid Reactive Substances (TBARS) Production in a Rat Model of Diffuse Axonal Injury. Effect of Gadolinium and Amiloride  

Microsoft Academic Search

This study evaluated the effect of mechanogated membrane ion channel blockers on brain catalase (CAT) activity and thiobarbituric acid reactive substances (TBARS) production after traumatic brain injury (TBI). A weight drop trauma model was used. Controls were sham-operated and received no weight drop. Gadolinium (GAD) or amiloride (AMI) were administered to control and experimental rats (30 min after TBI). Brain CAT

Alejandro Santos; Nuno Borges; António Cerejo; António Sarmento; Isabel Azevedo

2005-01-01

268

Ionizing radiation accelerates Drp1-dependent mitochondrial fission, which involves delayed mitochondrial reactive oxygen species production in normal human fibroblast-like cells  

Microsoft Academic Search

Ionizing radiation is known to increase intracellular level of reactive oxygen species (ROS) through mitochondrial dysfunction. Although it has been as a basis of radiation-induced genetic instability, the mechanism involving mitochondrial dysfunction remains unclear. Here we studied the dynamics of mitochondrial structure in normal human fibroblast like cells exposed to ionizing radiation. Delayed mitochondrial O2- production was peaked 3days after

Shinko Kobashigawa; Keiji Suzuki; Shunichi Yamashita

2011-01-01

269

Inelastic production of J/ ? mesons in photoproduction and deep inelastic scattering at HERA  

NASA Astrophysics Data System (ADS)

A measurement is presented of inelastic photo- and electroproduction of J/ ? mesons in ep scattering at HERA. The data were recorded with the H1 detector in the period from 2004 to 2007. Single and double differential cross sections are determined and the helicity distributions of the J/ ? mesons are analysed. The results are compared to theoretical predictions in the colour singlet model and in the framework of non-relativistic QCD. Calculations in the colour singlet model using a k T factorisation ansatz are able to give a good description of the data, while colour singlet model calculations to next-to-leading order in collinear factorisation underestimate the data.

Aaron, F. D.; Alexa, C.; Andreev, V.; Antunovic, B.; Backovic, S.; Baghdasaryan, A.; Barrelet, E.; Bartel, W.; Begzsuren, K.; Belousov, A.; Bizot, J. C.; Boudry, V.; Bozovic-Jelisavcic, I.; Bracinik, J.; Brandt, G.; Brinkmann, M.; Brisson, V.; Bruncko, D.; Bunyatyan, A.; Buschhorn, G.; Bystritskaya, L.; Campbell, A. J.; Cantun Avila, K. B.; Cerny, K.; Cerny, V.; Chekelian, V.; Cholewa, A.; Contreras, J. G.; Coughlan, J. A.; Cozzika, G.; Cvach, J.; Dainton, J. B.; Daum, K.; Deák, M.; Delcourt, B.; Delvax, J.; de Wolf, E. A.; Diaconu, C.; Dodonov, V.; Dossanov, A.; Dubak, A.; Eckerlin, G.; Efremenko, V.; Egli, S.; Eliseev, A.; Elsen, E.; Falkiewicz, A.; Favart, L.; Fedotov, A.; Felst, R.; Feltesse, J.; Ferencei, J.; Fischer, D.-J.; Fleischer, M.; Fomenko, A.; Gabathuler, E.; Gayler, J.; Ghazaryan, S.; Glazov, A.; Goerlich, L.; Gogitidze, N.; Gouzevitch, M.; Grab, C.; Grebenyuk, A.; Greenshaw, T.; Grell, B. R.; Grindhammer, G.; Habib, S.; Haidt, D.; Helebrant, C.; Henderson, R. C. W.; Hennekemper, E.; Henschel, H.; Herbst, M.; Herrera, G.; Hildebrandt, M.; Hiller, K. H.; Hoffmann, D.; Horisberger, R.; Hreus, T.; Jacquet, M.; Janssen, X.; Jönsson, L.; Jung, A. W.; Jung, H.; Kapichine, M.; Katzy, J.; Kenyon, I. R.; Kiesling, C.; Klein, M.; Kleinwort, C.; Kluge, T.; Knutsson, A.; Kogler, R.; Kostka, P.; Kraemer, M.; Krastev, K.; Kretzschmar, J.; Kropivnitskaya, A.; Krüger, K.; Kutak, K.; Landon, M. P. J.; Lange, W.; Laštovi?ka-Medin, G.; Laycock, P.; Lebedev, A.; Lendermann, V.; Levonian, S.; Li, G.; Lipka, K.; Liptaj, A.; List, B.; List, J.; Loktionova, N.; Lopez-Fernandez, R.; Lubimov, V.; Makankine, A.; Malinovski, E.; Marage, P.; Marti, Ll.; Martyn, H.-U.; Maxfield, S. J.; Mehta, A.; Meyer, A. B.; Meyer, H.; Meyer, J.; Mikocki, S.; Milcewicz-Mika, I.; Moreau, F.; Morozov, A.; Morris, J. V.; Mozer, M. U.; Mudrinic, M.; Müller, K.; Murín, P.; Naumann, Th.; Newman, P. R.; Niebuhr, C.; Nikiforov, A.; Nikitin, D.; Nowak, G.; Nowak, K.; Olsson, J. E.; Osman, S.; Ozerov, D.; Pahl, P.; Palichik, V.; Panagoulias, I.; Pandurovic, M.; Papadopoulou, Th.; Pascaud, C.; Patel, G. D.; Perez, E.; Petrukhin, A.; Picuric, I.; Piec, S.; Pitzl, D.; Pla?akyt?, R.; Pokorny, B.; Polifka, R.; Povh, B.; Radescu, V.; Raicevic, N.; Raspiareza, A.; Ravdandorj, T.; Reimer, P.; Rizvi, E.; Robmann, P.; Roosen, R.; Rostovtsev, A.; Rotaru, M.; Ruiz Tabasco, J. E.; Rusakov, S.; Šálek, D.; Sankey, D. P. C.; Sauter, M.; Sauvan, E.; Schmitt, S.; Schoeffel, L.; Schöning, A.; Schultz-Coulon, H.-C.; Sefkow, F.; Shaw-West, R. N.; Shtarkov, L. N.; Shushkevich, S.; Sloan, T.; Smiljanic, I.; Soloviev, Y.; Sopicki, P.; South, D.; Spaskov, V.; Specka, A.; Staykova, Z.; Steder, M.; Stella, B.; Stoicea, G.; Straumann, U.; Sunar, D.; Sykora, T.; Thompson, G.; Thompson, P. D.; Toll, T.; Tomasz, F.; Tran, T. H.; Traynor, D.; Truöl, P.; Tsakov, I.; Tseepeldorj, B.; Turnau, J.; Urban, K.; Valkárová, A.; Vallée, C.; van Mechelen, P.; Vargas Trevino, A.; Vazdik, Y.; Volchinski, V.; von den Driesch, M.; Wegener, D.; Wissing, Ch.; Wünsch, E.; Žá?ek, J.; Zálešák, J.; Zhang, Z.; Zhokin, A.; Zimmermann, T.; Zohrabyan, H.; Zomer, F.

2010-08-01

270

Forward-jet production in deep inelastic ep scattering at HERA  

NASA Astrophysics Data System (ADS)

Forward jet cross sections have been measured in neutral current deep inelastic scattering at low Bjorken-x with the ZEUS detector at HERA using an integrated luminosity of 81.8 pb-1. Measurements are presented for inclusive forward jets as well as for forward jets accompanied by a dijet system. The explored phase space, with jet pseudorapidity up to 4.3 is expected to be particularly sensitive to the dynamics of QCD parton evolution at low x. The measurements are compared to fixed-order QCD calculations and to leading-order parton-shower Monte Carlo models.

Chekanov, S.; Derrick, M.; Magill, S.; Musgrave, B.; Nicholass, D.; Repond, J.; Yoshida, R.; Mattingly, M. C. K.; Jechow, M.; Pavel, N.; Yagües Molina, A. G.; Antonelli, S.; Antonioli, P.; Bari, G.; Basile, M.; Bellagamba, L.; Bindi, M.; Boscherini, D.; Bruni, A.; Bruni, G.; Cifarelli, L.; Cindolo, F.; Contin, A.; Corradi, M.; de Pasquale, S.; Iacobucci, G.; Margotti, A.; Nania, R.; Polini, A.; Sartorelli, G.; Zichichi, A.; Bartsch, D.; Brock, I.; Hartmann, H.; Hilger, E.; Jakob, H.-P.; Jüngst, M.; Kind, O. M.; Nuncio-Quiroz, A. E.; Paul, E.; Renner, R.; Samson, U.; Schönberg, V.; Shehzadi, R.; Wlasenko, M.; Brook, N. H.; Heath, G. P.; Morris, J. D.; Capua, M.; Fazio, S.; Mastroberardino, A.; Schioppa, M.; Susinno, G.; Tassi, E.; Kim, J. Y.; Ma, K. J.; Ibrahim, Z. A.; Kamaluddin, B.; Wan Abdullah, W. A. T.; Ning, Y.; Ren, Z.; Sciulli, F.; Chwastowski, J.; Eskreys, A.; Figiel, J.; Galas, A.; Gil, M.; Olkiewicz, K.; Stopa, P.; Zawiejski, L.; Adamczyk, L.; Bo?d, T.; Grabowska-Bo?d, I.; Kisielewska, D.; ?ukasik, J.; Przybycie?, M.; Suszycki, L.; Kota?ski, A.; S?omi?ski, W.; Adler, V.; Behrens, U.; Bloch, I.; Blohm, C.; Bonato, A.; Borras, K.; Ciesielski, R.; Coppola, N.; Dossanov, A.; Drugakov, V.; Fourletova, J.; Geiser, A.; Gladkov, D.; Göttlicher, P.; Grebenyuk, J.; Gregor, I.; Haas, T.; Hain, W.; Horn, C.; Hüttmann, A.; Kahle, B.; Katkov, I. I.; Klein, U.; Kötz, U.; Kowalski, H.; Lobodzinska, E.; Löhr, B.; Mankel, R.; Melzer-Pellmann, I.-A.; Miglioranzi, S.; Montanari, A.; Namsoo, T.; Notz, D.; Rinaldi, L.; Roloff, P.; Rubinsky, I.; Santamarta, R.; Schneekloth, U.; Spiridonov, A.; Stadie, H.; Szuba, D.; Szuba, J.; Theedt, T.; Wolf, G.; Wrona, K.; Youngman, C.; Zeuner, W.; Lohmann, W.; Schlenstedt, S.; Barbagli, G.; Gallo, E.; Pelfer, P. G.; Bamberger, A.; Dobur, D.; Karstens, F.; Vlasov, N. N.; Bussey, P. J.; Doyle, A. T.; Dunne, W.; Forrest, M.; Saxon, D. H.; Skillicorn, I. O.; Gialas, I.; Papageorgiu, K.; Gosau, T.; Holm, U.; Klanner, R.; Lohrmann, E.; Salehi, H.; Schleper, P.; Schörner-Sadenius, T.; Sztuk, J.; Wichmann, K.; Wick, K.; Foudas, C.; Fry, C.; Long, K. R.; Tapper, A. D.; Kataoka, M.; Matsumoto, T.; Nagano, K.; Tokushuku, K.; Yamada, S.; Yamazaki, Y.; Barakbaev, A. N.; Boos, E. G.; Pokrovskiy, N. S.; Zhautykov, B. O.; Aushev, V.; Borodin, M.; Kozulia, A.; Lisovyi, M.; Son, D.; de Favereau, J.; Piotrzkowski, K.; Barreiro, F.; Glasman, C.; Jimenez, M.; Labarga, L.; Del Peso, J.; Ron, E.; Soares, M.; Terrón, J.; Zambrana, M.; Corriveau, F.; Liu, C.; Walsh, R.; Zhou, C.; Tsurugai, T.; Antonov, A.; Dolgoshein, B. A.; Sosnovtsev, V.; Stifutkin, A.; Suchkov, S.; Dementiev, R. K.; Ermolov, P. F.; Gladilin, L. K.; Khein, L. A.; Korzhavina, I. A.; Kuzmin, V. A.; Levchenko, B. B.; Lukina, O. Yu.; Proskuryakov, A. S.; Shcheglova, L. M.; Zotkin, D. S.; Zotkin, S. A.; Abt, I.; Büttner, C.; Caldwell, A.; Kollar, D.; Schmidke, W. B.; Sutiak, J.; Grigorescu, G.; Keramidas, A.; Koffeman, E.; Kooijman, P.; Pellegrino, A.; Tiecke, H.; Vázquez, M.; Wiggers, L.; Brümmer, N.; Bylsma, B.; Durkin, L. S.; Lee, A.; Ling, T. Y.; Allfrey, P. D.; Bell, M. A.; Cooper-Sarkar, A. M.; Devenish, R. C. E.; Ferrando, J.; Foster, B.; Korcsak-Gorzo, K.; Oliver, K.; Patel, S.; Roberfroid, V.; Robertson, A.; Straub, P. B.; Uribe-Estrada, C.; Walczak, R.; Bellan, P.; Bertolin, A.; Brugnera, R.; Carlin, R.; Dal Corso, F.; Dusini, S.; Garfagnini, A.; Limentani, S.; Longhin, A.; Stanco, L.; Turcato, M.; Oh, B. Y.; Raval, A.; Ukleja, J.; Whitmore, J. J.; Iga, Y.; D'Agostini, G.; Marini, G.; Nigro, A.; Cole, J. E.; Hart, J. C.; Abramowicz, H.; Gabareen, A.; Ingbir, R.; Kananov, S.; Levy, A.; Kuze, M.; Maeda, J.; Hori, R.; Kagawa, S.; Okazaki, N.; Shimizu, S.; Tawara, T.; Hamatsu, R.; Kaji, H.; Kitamura, S.; Ota, O.; Ri, Y. D.; Ferrero, M. I.; Monaco, V.; Sacchi, R.; Solano, A.; Arneodo, M.; Ruspa, M.; Fourletov, S.; Martin, J. F.; Boutle, S. K.; Butterworth, J. M.; Gwenlan, C.; Jones, T. W.; Loizides, J. H.; Sutton, M. R.; Wing, M.; Brzozowska, B.; Ciborowski, J.; Grzelak, G.; Kulinski, P.; ?u?niak, P.; Malka, J.; Nowak, R. J.; Pawlak, J. M.; Tymieniecka, T.; Ukleja, A.; ?arnecki, A. F.; Adamus, M.; Plucinski, P.; Eisenberg, Y.; Giller, I.; Hochman, D.; Karshon, U.; Rosin, M.; Brownson, E.; Danielson, T.; Everett, A.; Kçira, D.; Reeder, D. D.; Ryan, P.; Savin, A. A.; Smith, W. H.; Wolfe, H.; Bhadra, S.; Catterall, C. D.; Cui, Y.; Hartner, G.; Menary, S.; Noor, U.; Standage, J.; Whyte, J.

2007-11-01

271

Forward-jet production in deep inelastic ep scattering at HERA.  

SciTech Connect

Forward jet cross sections have been measured in neutral current deep inelastic scattering at low Bjorken-x with the ZEUS detector at HERA using an integrated luminosity of 81.8 pb{sup -1}. Measurements are presented for inclusive forward jets as well as for forward jets accompanied by a dijet system. The explored phase space, with jet pseudorapidity up to 4.3 is expected to be particularly sensitive to the dynamics of QCD parton evolution at low x. The measurements are compared to fixed-order QCD calculations and to leading-order parton-shower Monte Carlo models.

Chekanov, S.; Derrick, M.; Magill, S.; Musgrave, B.; Repond, J.; Yoshida, R.; High Energy Physics; Zeus Collaboration

2007-01-01

272

Reactive Arthritis  

MedlinePLUS

... reactive arthritis. The most common ones include: Chlamydia Salmonella Shigella Yersinia Campylobacter Reactive arthritis isn't contagious. ... borne bacteria that can cause reactive arthritis, including salmonella, shigella, yersinia and campylobacter. In addition, practice safe ...

273

Sorafenib-induced hepatocellular carcinoma cell death depends on reactive oxygen species production in vitro and in vivo.  

PubMed

Sorafenib is presently the only effective therapy in advanced hepatocellular carcinoma (HCC). Because most anticancer drugs act, at least in part, through the generation of reactive oxygen species, we investigated whether sorafenib can induce an oxidative stress. The effects of sorafenib on intracellular ROS production and cell death were assessed in vitro in human (HepG2) and murine (Hepa 1.6) HCC cell lines and human endothelial cells (HUVEC) as controls. In addition, 26 sera from HCC patients treated by sorafenib were analyzed for serum levels of advanced oxidation protein products (AOPP). Sorafenib significantly and dose-dependently enhanced in vitro ROS production by HCC cells. The SOD mimic MnTBAP decreased sorafenib-induced lysis of HepG2 cells by 20% and of Hepa 1.6 cells by 75% compared with HCC cells treated with 5 mg/L sorafenib alone. MnTBAP significantly enhanced by 25% tumor growth in mice treated by sorafenib. On the other hand, serum levels of AOPP were higher in HCC patients treated by sorafenib than in sera collected before treatment (P < 0.001). An increase in serum AOPP concentration ?0.2 ?mol/L chloramine T equivalent after 15 days of treatment is a predictive factor for sorafenib response with higher progression free survival (P < 0.05) and overall survival rates (P < 0.05). As a conclusion, sorafenib dose-dependently induces the generation of ROS in tumor cells in vitro and in vivo. The sera of Sorafenib-treated HCC patients contain increased AOPP levels that are correlated with the clinical effectiveness of sorafenib and can be used as a marker of effectiveness of the drug. . PMID:22902857

Coriat, Romain; Nicco, Carole; Chéreau, Christiane; Mir, Olivier; Alexandre, Jérôme; Ropert, Stanislas; Weill, Bernard; Chaussade, Stanislas; Goldwasser, François; Batteux, Frédéric

2012-08-17

274

Peptide Ozonolysis: Product Structures and Relative Reactivities for Oxidation of Tyrosine and Histidine Residues  

SciTech Connect

Angiotensin II (DRVYIHPF) and two analogs (DRVYIAPA, and DRVAIHPA) were used as model systems to study the ozonolysis of peptides containing tyrosine and histidine residues. The ESI mass spectrum of angiotensin II following exposure to ozone showed the formation of adducts containing one, three and four oxygen atoms. CID and SID spectra of these adducts were consistent with formation of Tyr + O and His + 3O as expected from previous work with amino acids. Additional ions in the CID and SID spectra suggested formation of Tyr + 3O and a small amount of Phe + O. Two analogs were also studied, one in which His and Phe were replaced by Ala (DRVYIAPA) and the other in which Tyr and Phe were replaced by Ala (DRVAIHPA). Exposure of DRVYIAPA to ozone resulted in the addition of one and three oxygen atoms, while DRVAIHPA showed only the addition of three oxygen atoms. Tandem mass spectra of these adducts confirmed the formation of Tyr + 3O in addition to Tyr + O and His + 3O. Other noteworthy minor oxidation products were observed from these analogs including Tyr + 34 u, His + 34 u, and His + 82 u. Modified reaction schemes for peptide ozonolysis are proposed which account for each of these newly observed adducts.

Lloyd, J A.; Spraggins, Jeffrey M.; Johnston, Murray V.; Laskin, Julia

2006-08-31

275

Advanced glycation end products delay corneal epithelial wound healing through reactive oxygen species generation.  

PubMed

Delayed healing of corneal epithelial wounds is a serious complication in diabetes. Advanced glycation end products (AGEs) are intimately associated with the diabetic complications and are deleterious to the wound healing process. However, the effect of AGEs on corneal epithelial wound healing has not yet been evaluated. In the present study, we investigated the effect of AGE-modified bovine serum albumin (BSA) on corneal epithelial wound healing and its underlying mechanisms. Our data showed that AGE-BSA significantly increased the generation of intracellular ROS in telomerase-immortalized human corneal epithelial cells. However, the generation of intracellular ROS was completely inhibited by antioxidant N-acetylcysteine (NAC), anti-receptor of AGEs (RAGE) antibodies, or the inhibitor of NADPH oxidase. Moreover, AGE-BSA increased NADPH oxidase activity and protein expression of NADPH oxidase subunits, p22phox and Nox4, but anti-RAGE antibodies eliminated these effects. Furthermore, prevention of intracellular ROS generation using NAC or anti-RAGE antibodies rescued AGE-BSA-delayed epithelial wound healing in porcine corneal organ culture. In conclusion, our results demonstrated that AGE-BSA impaired corneal epithelial wound healing ex vivo. AGE-BSA increased intracellular ROS generation through NADPH oxidase activation, which accounted for the delayed corneal epithelial wound healing. These results may provide better insights for understanding the mechanism of delayed healing of corneal epithelial wounds in diabetes. PMID:23955437

Shi, Long; Chen, Hongmei; Yu, Xiaoming; Wu, Xinyi

2013-08-18

276

Efficient cyanoaromatic photosensitizers for singlet oxygen production: synthesis and characterization of the transient reactive species.  

PubMed

In order to graft cyanoaromatic molecules onto various inert supports, we designed two new cyanoanthracene derivatives of benzo[b]triphenylene-9,14-dicarbonitrile (DBTP, ), which already demonstrated good photosensitizing properties. We synthesized 3-(N-hydroxypropyl)carboxamido-9,14-dicyanobenzo[b]triphenylene, and 3-(N-N'-Boc-aminohexyl)carboxamido-9,14-dicyanobenzo[b]triphenylene, and compared their photophysical properties in acetonitrile relative to those of the parent compound and its carboxylic derivative 9,14-dicyanobenzo[b]triphenylene-3-carboxylic acid, . The transient species were analysed and the quantum yields of singlet oxygen production (??) determined in acetonitrile. The effect of chemical functionalization can be considered negligible, since absorption spectra, fluorescence emission spectra and fluorescence lifetimes do not significantly change with the substituent. The triplet-triplet absorption spectra and the triplet excited state lifetimes are similar for the whole series. For compounds high values of ??, close to that of the standard sensitizer 1H-phenalen-1-one (PN, ?? ? 1), and higher than that of the well-known photosensitizer 9,10-dicyanoanthracene (), are due to very efficient intersystem crossing from the singlet to the triplet excited state and subsequent energy transfer to ground state oxygen ((3)O2). They belong to a class of very efficient photosensitizers, absorbing visible light and stable under irradiation, they may be functionalized without significant changes to their photophysical behaviour, and grafted onto various supports. PMID:24013434

Ronzani, Filippo; Arzoumanian, Emmanuel; Blanc, Sylvie; Bordat, Patrice; Pigot, Thierry; Cugnet, Cyril; Oliveros, Esther; Sarakha, Mohamed; Richard, Claire; Lacombe, Sylvie

2013-09-25

277

Molecular beam studies of free-radical processes: photodissociation, inelastic and reactive collisions  

Microsoft Academic Search

In this review, the production and detection of a wide range of unstable free-radical species under molecular beam conditions are described. The use of such molecular beam methods to study the photodissociation and inelastic and reactive scattering of free radicals in recent years is reviewed. A selection of the many experiments on the photodissociation of radicals that have been performed

J. Christopher Whitehead

1996-01-01

278

Multiple parton interactions and forward double pion production in pp and dA scattering  

SciTech Connect

We estimate the contributions by double-parton interactions to the cross sections for pp{yields}{pi}{sup 0}{pi}{sup 0}X and dA{yields}{pi}{sup 0}{pi}{sup 0}X at the Relativistic Heavy Ion Collider (RHIC). We find that such contributions become important at large forward rapidities of the produced pions. This is, in particular, the case for dA scattering, where they strongly enhance the azimuthal-angular independent pedestal component of the cross section, providing a natural explanation of this feature of the RHIC dA data. We argue that the discussed processes open a window to studies of double quark distributions in nucleons. We also briefly address the roles of shadowing and energy loss in dA scattering, which we show to affect the double-inclusive pion cross section much more strongly than the single-inclusive one. We discuss the implications of our results for the interpretation of pion azimuthal correlations.

Strikman, M. [Department of Physics, Pennsylvania State University, University Park, Pennsylvania (United States); Vogelsang, W. [Institute for Theoretical Physics, Universitaet Tuebingen, Auf der Morgenstelle 14, D-72076 Tuebingen (Germany)

2011-02-01

279

Effects of nutrients, salinity, pH and light:dark cycle on the production of reactive oxygen species in the alga Chattonella marina  

Microsoft Academic Search

Experiments were carried out to investigate the effects of nutrients, salinity, pH and light:dark cycle on growth rate and production of reactive oxygen species (ROS) by Chattonella marina, a harmful algal bloom (HAB) species that often causes fish kills. Different nitrogen forms (organic-N and inorganic-N), N:P ratios, light:dark cycles and salinity significantly influenced algal growth, but not ROS production. However,

Wenhua Liu; Doris W. T. Au; Donald M. Anderson; Paul K. S. Lam; Rudolf S. S. Wu

2007-01-01

280

Effect of culture condition and cell-permeable superoxide dismutase on levels of reactive oxygen species (ROS) production in “in vitro” produced sheep embryos  

Microsoft Academic Search

This study was carried out to evaluate the pattern of reactive oxygen species (ROS) production variation during in vitro oocyte development and maturation and embryonic development in sheep, and to investigate whether embryo culture conditions and the presence of cell-permeable superoxide dismutase mimetic [Manganese (III) meso-tetrakis (4-benzoic acid) porphyrin (MnTBAP)] can influence the ROS production pattern. Oocytes at the germinal

S. Ostad Hosseini; F. Aghaee; S. M. Hosseini; M. Hajian; M. Forouzanfar; M. Noorbakhshnia; H. Gourabi; A. H. Shahverdi; A. Vosough Taghi Dizaj; M. H. Nasr-Esfahani

2011-01-01

281

HCV regulates TGF-?1 production through the generation of reactive oxygen species in an NF?B-dependent manner  

PubMed Central

Background & Aims The generation of oxidative stress and TGF-?1 production play important roles in liver fibrogenesis. We have previously shown that HCV increases hepatocyte TGF-?1 expression. However, the mechanisms by which this induction occurs have not been well studied. We explored the possibility that HCV infection regulates TGF-?1 expression through generation of reactive oxygen species (ROS), which act through one or more of the p38 MAPK, ERK, JNK, and NF?B signaling pathways to induce TGF-?1 expression. Methods and Results In this study, we demonstrated using the infectious JFH1 model that HCV induces ROS and TGF-?1 expression. We further found that JFH1 activates the phosphorylation of p38 MAPK, JNK, ERK, and NF?B. Through use of small molecule inhibitors and siRNAs to knock down these pathways, we found that HCV-mediated TGF-?1 enhancement occurs through a ROS-induced and p38 MAPK, JNK, ERK1/2, NF?B-dependent pathway. Conclusions These findings provide further evidence to support the hypothesis that HCV enhances hepatic fibrosis progression through the generation of ROS and induction of TGF-?1. Strategies to limit the viral induction of oxidative stress appear to be warranted to inhibit fibrogenesis.

Lin, Wenyu; Tsai, Wei-Lun; Shao, Run-Xuan; Wu, Guoyang; Peng, Lee F.; Barlow, Lydia L.; Chung, Woo Jin; Zhang, Leiliang; Zhao, Hong; Jang, Jae-Young; Chung, Raymond T.

2010-01-01

282

Production of hybrid diesel fuel precursors from carbohydrates and petrochemicals using formic acid as a reactive solvent.  

PubMed

We report the one-pot alkylation of mesitylene with carbohydrate-derived 5-(hydroxymethyl)furfural (HMF) as a step toward diesel-range liquids. Using FeCl(3) as a catalyst, HMF is shown to alkylate toluene, xylene, and mesitylene in high yields in CH(2)Cl(2) and MeNO(2) solvents. Efforts to extend this reaction to greener or safer solvents showed that most ether-based solvents are unsatisfactory. Acid catalysts (e.g, p-TsOH) also proved to be ineffective. Using formic acid as a reactive solvent, mesitylene could be alkylated to give mesitylmethylfurfural (MMF) starting from fructose with yields up to approximately 70 %. The reaction of fructose with formic acid in the absence of mesitylene gave rise to low yields of the formate ester of HMF, which indicates the stabilizing effect of replacing the hydroxyl substituent with mesityl. The arene also serves as a second phase into which the product is extracted. Even by using formic acid, the mesitylation of less expensive precursors such as glucose and cellulose proceeded only in modest yields (ca. 20 %). These simpler substrates were found to undergo mesitylation by using hydrogen chloride/formic acid via the intermediate chloromethylfurfural. PMID:23281330

Zhou, Xiaoyuan; Rauchfuss, Thomas B

2012-12-23

283

Exposure to lambda-cyhalothrin, a synthetic pyrethroid, increases reactive oxygen species production and induces genotoxicity in rat peripheral blood.  

PubMed

Lambda-cyhalothrin (LTC) is a synthetic pyrethroid with a broad spectrum of insecticidal and acaricidal activities used to control a wide range of insect pests in a variety of applications. However, there is little known about its adverse effects, in particular those related to its genotoxicity in humans. To elucidate the genotoxicity mechanisms of LTC, the micronuclei (MN) frequencies, the levels of reactive oxygen species (ROS), erythrocyte osmotic fragility, nitrite (NO) formation, protein carbonyl (PCO) levels and malondialdehyde (MDA) production were evaluated for a period of 7, 14 and 21 days. Our results show that exposure rat to LTC (1/10DL50 = 6.23 mg/kg) for a period of 7, 14 and 21 days induced a noticeable genotoxic effect in rat peripheral blood evidenced by a significant increase in the frequency of MN only at day 21 of treatment. Significant differences between the two groups were observed in erythrocyte osmotic fragility. Further, a significant (p < 0.01) increase in ROS contents, NO formation, PCO levels and lipid peroxidation in erythrocytes were observed at different times of treatments, suggesting the implication of oxidative stress in its toxicity. These results confirm the genotoxic and the pro-oxidant effects of LTC in rat peripheral blood. PMID:23406951

Fetoui, Hamadi; Feki, Ameni; Ben Salah, Ghada; Kamoun, Hassen; Fakhfakh, Feiza; Gdoura, Radhouane

2013-02-13

284

Activating mutations in protein tyrosine phosphatase Ptpn11 (Shp2) enhance reactive oxygen species production that contributes to myeloproliferative disorder.  

PubMed

Gain of function (GOF) mutations in protein tyrosine phosphatase Ptpn11 have been identified in childhood leukemias, and these mutations are sufficient to drive the development of myeloproliferative disorder and malignant leukemias in mice. However, the molecular mechanisms by which Ptpn11 mutations induce these malignancies are not completely understood. Here we report that Ptpn11 GOF mutations cause cytokine hypersensitivity in hematopoietic cells partly by enhancing the production of reactive oxygen species (ROS). GOF mutations D61G or E76K in Ptpn11 increased ROS levels in myeloid progenitors but not in hematopoietic stem cells. Increased ROS enhanced cellular responses to cytokines by promoting cytokine signaling. Treatment with an antioxidant partially corrected cytokine hypersensitivity in Ptpn11 mutant progenitors. Further analyses demonstrated that Ptpn11 mutations increased mitochondrial aerobic metabolism by interacting with a novel substrate in the mitochondria. This study provides new insights into the pathogenic effects of GOF mutations of Ptpn11 and implies that antioxidants may have a therapeutic benefit for the leukemic patients with these mutations. PMID:23675459

Xu, Dan; Zheng, Hong; Yu, Wen-Mei; Qu, Cheng-Kui

2013-05-10

285

Fc?R-driven release of IL-6 by macrophages requires NOX2-dependent production of reactive oxygen species.  

PubMed

Activation of the Fc?R via antigen containing immune complexes can lead to the generation of reactive oxygen species, which are potent signal transducing molecules. However, whether ROS contribute to Fc?R signaling has not been studied extensively. We set out to elucidate the role of NADPH oxidase-generated ROS in macrophage activation following Fc?R engagement using antigen-containing immune complexes. We hypothesized that NOX2 generated ROS is necessary for propagation of downstream Fc?R signaling and initiation of the innate immune response. Following exposure of murine bone marrow-derived macrophages (BMDMs) to inactivated Francisella tularensis (iFt)-containing immune complexes, we observed a significant increase in the innate inflammatory cytokine IL-6 at 24 h compared with macrophages treated with Ft LVS-containing immune complexes. Ligation of the Fc?R by opsonized Ft also results in significant ROS production. Macrophages lacking the gp91(phox) subunit of NOX2 fail to produce ROS upon Fc?R ligation, resulting in decreased Akt phosphorylation and a reduction in the levels of IL-6 compared with wild type macrophages. Similar results were seen following infection of BMDMs with catalase deficient Ft that fail to scavenge hydrogen peroxide. In conclusion, our findings demonstrate that ROS participate in elicitation of an effective innate immune in response to antigen-containing immune complexes through Fc?R. PMID:23857584

Franchini, Anthony M; Hunt, Danielle; Melendez, J Andres; Drake, James R

2013-07-15

286

Activating Mutations in Protein Tyrosine Phosphatase Ptpn11 (Shp2) Enhance Reactive Oxygen Species Production That Contributes to Myeloproliferative Disorder  

PubMed Central

Gain of function (GOF) mutations in protein tyrosine phosphatase Ptpn11 have been identified in childhood leukemias, and these mutations are sufficient to drive the development of myeloproliferative disorder and malignant leukemias in mice. However, the molecular mechanisms by which Ptpn11 mutations induce these malignancies are not completely understood. Here we report that Ptpn11 GOF mutations cause cytokine hypersensitivity in hematopoietic cells partly by enhancing the production of reactive oxygen species (ROS). GOF mutations D61G or E76K in Ptpn11 increased ROS levels in myeloid progenitors but not in hematopoietic stem cells. Increased ROS enhanced cellular responses to cytokines by promoting cytokine signaling. Treatment with an antioxidant partially corrected cytokine hypersensitivity in Ptpn11 mutant progenitors. Further analyses demonstrated that Ptpn11 mutations increased mitochondrial aerobic metabolism by interacting with a novel substrate in the mitochondria. This study provides new insights into the pathogenic effects of GOF mutations of Ptpn11 and implies that antioxidants may have a therapeutic benefit for the leukemic patients with these mutations.

Yu, Wen-Mei; Qu, Cheng-Kui

2013-01-01

287

The Weak Production of {lambda} Particles in Muon and Tau Scattering From Protons  

SciTech Connect

We calculate and discuss the differential cross section for the weak, strangeness changing, processes, {mu}- + p {yields} v{mu} + {lambda} and {tau}- + p {yields} v{tau} + {lambda}, for incoming muon energies from threshold to 5.0 GeV and for an incoming tau of 20.0 GeV. The relatively high energy of the tau lepton is made necessary by its short lifetime. We obtain contributions from the form factors and particularly the interference terms with a view to observing those parts of the cross section which are suppressed in the corresponding electron induced process due to the small size of the electron mass. We make use of SU(3) relations and experimental data from electron scattering and {lambda} beta decay so that the calculation presented is phenomenological in nature.

Mintz, Stephan L. [Physics Department, Florida International University, Miami, Florida, 33199 (United States)

2004-02-05

288

Analysis of atmospheric corrosion products of steel and coated steel by means of scattering Mössbauer spectrometry  

NASA Astrophysics Data System (ADS)

Wearthering steels treated with and without zinc phosphate solution were exposed to atmosphere for 15 years and rust layers produced on the steels were analysed by scattering Mössbauer spectrometry (CEMS and XMS). ?-FeOOH, fine ?-FeOOH, 5Fe2O3·9H2O, ?-Fe2O3 and Fe3O4 were identified to be present in the rust formed on the steel without phosphate coating. Large particles of ?-Fe2O3 and Fe3O4 formed on the uncoated steel exposed to atmosphere in a position facing north on vertical plane. The layer structure of rust was affected by the position. The thin rust layer formed on the phosphate + carylite resin coated steel was considered to consist of ?-FeOOH, fine ?-FeOOH, and fine ?-Fe2O3.

Nomura, Kiyoshi; Ujihira, Yusuke

1986-02-01

289

Interferon beta-1b inhibits reactive oxygen species production in peripheral blood monocytes of patients with relapsing-remitting multiple sclerosis.  

PubMed

We studied the rate of reactive oxygen species (ROS) production by monocytes 'ex vivo' in a cohort of healthy individuals, in a group of MS patients undergoing treatment with interferon beta-1b and another group of MS patients who refused treatment with interferon beta-1b. The rate of ROS production in healthy individuals was slightly lower than in non-treated MS patients. The lower rate of ROS production was obtained in monocytes of MS patients treated with interferon beta-1b. These results indicate that the treatment of relapsing-remitting MS patients with interferon beta-1b rendered the NADPH oxidase of the monocytes less sensitive to trigger reactive oxygen species (ROS). PMID:9761453

Lucas, M; Sánchez-Soliño, O; Solano, F; Izquierdo, G

1998-08-01

290

Reactivation of desensitized formyl peptide receptors by platelet activating factor: a novel receptor cross talk mechanism regulating neutrophil superoxide anion production.  

PubMed

Neutrophils express different chemoattractant receptors of importance for guiding the cells from the blood stream to sites of inflammation. These receptors communicate with one another, a cross talk manifested as hierarchical, heterologous receptor desensitization. We describe a new receptor cross talk mechanism, by which desensitized formyl peptide receptors (FPRdes) can be reactivated. FPR desensitization is induced through binding of specific FPR agonists and is reached after a short period of active signaling. The mechanism that transfers the receptor to a non-signaling desensitized state is not known, and a signaling pathway has so far not been described, that transfers FPRdes back to an active signaling state. The reactivation signal was generated by PAF stimulation of its receptor (PAFR) and the cross talk was uni-directional. LatrunculinA, an inhibitor of actin polymerization, induced a similar reactivation of FPRdes as PAF while the phosphatase inhibitor CalyculinA inhibited reactivation, suggesting a role for the actin cytoskeleton in receptor desensitization and reactivation. The activated PAFR could, however, reactivate FPRdes also when the cytoskeleton was disrupted prior to activation. The receptor cross talk model presented prophesies that the contact on the inner leaflet of the plasma membrane that blocks signaling between the G-protein and the FPR is not a point of no return; the receptor cross-talk from the PAFRs to the FPRdes initiates an actin-independent signaling pathway that turns desensitized receptors back to a signaling state. This represents a novel mechanism for amplification of neutrophil production of reactive oxygen species. PMID:23555913

Forsman, Huamei; Önnheim, Karin; Andréasson, Emil; Christenson, Karin; Karlsson, Anna; Bylund, Johan; Dahlgren, Claes

2013-03-28

291

Connection Between the Leading Logarithms and Hard Scattering Approaches to Lepton Pair Production.  

National Technical Information Service (NTIS)

The modification is reviewed of the leading logarithms technique which allows for the unified description of the lepton pair production at small and large angles. Transverse momentum distribution of the lepton pair, which interpolates between both regions...

J. Wosiek

1979-01-01

292

Same-sign WW production in proton-nucleus collisions at the LHC as a signal for double parton scattering  

NASA Astrophysics Data System (ADS)

The production of same-sign W-boson pairs from double parton scatterings (DPS) in proton-lead (p-Pb) collisions at the CERN Large Hadron Collider is studied. The signal and background cross sections are estimated with next-to-leading-order perturbative QCD calculations using nuclear parton distribution functions for the Pb ion. At sNN=8.8 TeV the cross section for the DPS process is about 150 pb, i.e. 600 times larger than that in proton-proton collisions at the same centre-of-mass energy and 1.5 times higher than the p-Pb?W±W±+2-jets single-parton background. The measurement of such a process, where 10 events with fully leptonic W's decays are expected after cuts in 2 pb, would constitute an unambiguous DPS signal and would help determine the effective ?eff parameter characterising the transverse distribution of partons in the proton.

d'Enterria, David; Snigirev, Alexander M.

2013-01-01

293

Muramyl-dipeptide-induced mitochondrial proton leak in macrophages is associated with upregulation of uncoupling protein 2 and the production of reactive oxygen and reactive nitrogen species.  

PubMed

The synthetic immunomodulator muramyl dipeptide (MDP) has been shown to induce, in vivo, mitochondrial proton leak. In the present work, we extended these findings to the cellular level and confirmed the effects of MDP in vitro on murine macrophages. The macrophage system was then used to analyse the mechanism of the MDP-induced mitochondrial proton leak. Our results demonstrate that the cellular levels of superoxide anion and nitric oxide were significantly elevated in response to MDP. Moreover, isolated mitochondria from cells treated with MDP presented a significant decrease in respiratory control ratio, an effect that was absent following treatment with a non-toxic analogue such as murabutide. Stimulation of cells with MDP, but not with murabutide, rapidly upregulates the expression of the mitochondrial protein uncoupling protein 2 (UCP2), and pretreatment with vitamin E attenuates upregulation of UCP2. These findings suggest that the MDP-induced reactive species upregulate UCP2 expression in order to counteract the effects of MDP on mitochondrial respiratory efficiency. PMID:21722312

El-Khoury, Takla G; Bahr, Georges M; Echtay, Karim S

2011-08-02

294

In-season root-zone N management for mitigating greenhouse gas emission and reactive N losses in intensive wheat production.  

PubMed

Although both the grain yields and environmental costs of nitrogen (N) fertilization are gaining more public and scientific debate, the complex linkages among crop productivity, N application rate, environmental footprints, and the consequences of improved N management are not well understood. We considered the concept of linking greenhouse gas (GHG) emission, reactive N losses, and N fertilizer application rates with crop productivity to determine the response of the GHG emission and reactive N losses to N surplus and further evaluated the potential to reduce these N environmental footprints by in-season root-zone N management. A meta-analysis suggested an exponential increase in the response of direct N2O emissions and nitrate leaching to an increasing N surplus, while NH3 volatilization increased linearly with an increasing N application rate for intensive wheat production in north China. The GHG emission and reactive N losses during N fertilizer application increased exponentially with an increasing N surplus. By pooling all 121 on-farm experimental sites, an in-season root-zone N management strategy was shown to reduce the N application rate by 61% from 325 kg N ha(-1) to 128 kg N ha(-1) compared to the farmers' N practice, with no loss in wheat grain yield. As a result, the intensity of GHG emission and reactive N losses were reduced by 77% and 80%, respectively. The intensity of GHG emission and reactive N losses can be further reduced due to the improved N recovery and increased grain yield achieved by best crop management. In conclusion, N recovery efficiency and yield improvements should be used to reduce future agricultural N environmental footprints, rather than reducing the N application rate. PMID:23662999

Cui, Zhenling; Yue, Shanchao; Wang, Guiliang; Zhang, Fusuo; Chen, Xinping

2013-05-23

295

Forward jet production in deep inelastic ep scattering and low-x parton dynamics at HERA  

NASA Astrophysics Data System (ADS)

Differential inclusive jet cross sections in neutral current deep inelastic ep scattering have been measured with the ZEUS detector using an integrated luminosity of 38.7 pb-1. The jets have been identified using the k cluster algorithm in the longitudinally invariant inclusive mode in the laboratory frame; they have been selected with jet transverse energy, ETjet above 6 GeV and jet pseudorapidity, ?, between -1 and 3. Measurements of cross sections as functions of ETjet, Björken x and the photon virtuality, Q, are presented. Three phase-space regions have been selected in order to study parton dynamics from the most global to the most restrictive region of forward-going (close to the proton-beam direction) jets at low x, where the effects of BFKL evolution might be present. The measurements have been compared to the predictions of leading-logarithm parton-shower Monte Carlo models and fixed-order perturbative QCD calculations. In the forward region, O(?s1) QCD calculations underestimate the data up to an order of magnitude at low x. An improved description of the data in this region is obtained by including O(?s2) QCD corrections, which account for the lowest-order tˆ-channel gluon-exchange diagrams, highlighting the importance of such terms in the parton dynamics at low x.

ZEUS Collaboration; Chekanov, S.; Derrick, M.; Magill, S.; Miglioranzi, S.; Musgrave, B.; Repond, J.; Yoshida, R.; Mattingly, M. C. K.; Pavel, N.; Yagües Molina, A. G.; Antonioli, P.; Bari, G.; Basile, M.; Bellagamba, L.; Boscherini, D.; Bruni, A.; Bruni, G.; Cara Romeo, G.; Cifarelli, L.; Cindolo, F.; Contin, A.; Corradi, M.; de Pasquale, S.; Giusti, P.; Iacobucci, G.; Margotti, A.; Montanari, A.; Nania, R.; Palmonari, F.; Pesci, A.; Polini, A.; Rinaldi, L.; Sartorelli, G.; Zichichi, A.; Aghuzumtsyan, G.; Bartsch, D.; Brock, I.; Goers, S.; Hartmann, H.; Hilger, E.; Irrgang, P.; Jakob, H.-P.; Kind, O.; Meyer, U.; Paul, E.; Rautenberg, J.; Renner, R.; Voss, K. C.; Wang, M.; Wlasenko, M.; Bailey, D. S.; Brook, N. H.; Cole, J. E.; Heath, G. P.; Namsoo, T.; Robins, S.; Capua, M.; Mastroberardino, A.; Schioppa, M.; Susinno, G.; Tassi, E.; Kim, J. Y.; Ma, K. J.; Helbich, M.; Ning, Y.; Ren, Z.; Schmidke, W. B.; Sciulli, F.; Chwastowski, J.; Eskreys, A.; Figiel, J.; Galas, A.; Olkiewicz, K.; Stopa, P.; Szuba, D.; Zawiejski, L.; Adamczyk, L.; Bo?d, T.; Grabowska-Bo?d, I.; Kisielewska, D.; Kowal, A. M.; ?ukasik, J.; Przybycie?, M.; Suszycki, L.; Szuba, J.; Kota?ski, A.; S?omi?ski, W.; Adler, V.; Behrens, U.; Bloch, I.; Borras, K.; Drews, G.; Fourletova, J.; Geiser, A.; Gladkov, D.; Göttlicher, P.; Gutsche, O.; Haas, T.; Hain, W.; Horn, C.; Kahle, B.; Kötz, U.; Kowalski, H.; Kramberger, G.; Lelas, D.; Lim, H.; Löhr, B.; Mankel, R.; Melzer-Pellmann, I.-A.; Nguyen, C. N.; Notz, D.; Nuncio-Quiroz, A. E.; Raval, A.; Santamarta, R.; Schneekloth, U.; Stösslein, U.; Wolf, G.; Youngman, C.; Zeuner, W.; Schlenstedt, S.; Barbagli, G.; Gallo, E.; Genta, C.; Pelfer, P. G.; Bamberger, A.; Benen, A.; Karstens, F.; Dobur, D.; Vlasov, N. N.; Bussey, P. J.; Doyle, A. T.; Ferrando, J.; Hamilton, J.; Hanlon, S.; Saxon, D. H.; Skillicorn, I. O.; Gialas, I.; Carli, T.; Gosau, T.; Holm, U.; Krumnack, N.; Lohrmann, E.; Milite, M.; Salehi, H.; Schleper, P.; Schörner-Sadenius, T.; Stonjek, S.; Wichmann, K.; Wick, K.; Ziegler, A.; Ziegler, Ar.; Collins-Tooth, C.; Foudas, C.; Fry, C.; Gonçalo, R.; Long, K. R.; Tapper, A. D.; Kataoka, M.; Nagano, K.; Tokushuku, K.; Yamada, S.; Yamazaki, Y.; Barakbaev, A. N.; Boos, E. G.; Pokrovskiy, N. S.; Zhautykov, B. O.; Son, D.; de Favereau, J.; Piotrzkowski, K.; Barreiro, F.; Glasman, C.; González, O.; Jimenez, M.; Labarga, L.; del Peso, J.; Terrón, J.; Zambrana, M.; Barbi, M.; Corriveau, F.; Liu, C.; Padhi, S.; Plamondon, M.; Stairs, D. G.; Walsh, R.; Zhou, C.; Tsurugai, T.; Antonov, A.; Danilov, P.; Dolgoshein, B. A.; Sosnovtsev, V.; Stifutkin, A.; Suchkov, S.; Dementiev, R. K.; Ermolov, P. F.; Gladilin, L. K.; Katkov, I. I.; Khein, L. A.; Korzhavina, I. A.; Kuzmin, V. A.; Levchenko, B. B.; Lukina, O. Yu.; Proskuryakov, A. S.; Shcheglova, L. M.; Zotkin, D. S.; Zotkin, S. A.; Abt, I.; Büttner, C.; Caldwell, A.; Liu, X.; Sutiak, J.; Coppola, N.; Grigorescu, G.; Grijpink, S.; Keramidas, A.; Koffeman, E.; Kooijman, P.; Maddox, E.; Pellegrino, A.; Schagen, S.; Tiecke, H.; Vázquez, M.; Wiggers, L.; de Wolf, E.; Brümmer, N.; Bylsma, B.; Durkin, L. S.; Ling, T. Y.; Allfrey, P. D.; Bell, M. A.; Cooper, A. M.; Cottrell, A.; Devenish, R. C. E.; Foster, B.; Grzelak, G.; Gwenlan, C.; Kohno, T.; Patel, S.; Straub, P. B.; Walczak, R.; Bellan, P.; Bertolin, A.; Brugnera, R.; Carlin, R.; Ciesielski, R.; dal Corso, F.; Dusini, S.; Garfagnini, A.; Limentani, S.; Longhin, A.; Stanco, L.; Turcato, M.; Heaphy, E. A.; Metlica, F.; Oh, B. Y.; Whitmore, J. J.; Iga, Y.; D'Agostini, G.; Marini, G.; Nigro, A.; Hart, J. C.; Abramowicz, H.; Gabareen, A.; Kananov, S.; Kreisel, A.; Levy, A.; Kuze, M.; Kagawa, S.; Tawara, T.; Hamatsu, R.; Kaji, H.; Kitamura, S.; Matsuzawa, K.; Ota, O.; Ri, Y. D.; Costa, M.; Ferrero, M. I.; Monaco, V.; Sacchi, R.; Solano, A.; Arneodo, M.; Ruspa, M.; Fourletov, S.; Koop, T.; Martin, J. F.; Mirea, A.; Butterworth, J. M.; Hall-Wilton, R.; Jones, T. W.; Loizides, J. H.; Sutton, M. R.; Targett-Adams, C.; Wing, M.; Ciborowski, J.; Kulinski, P.; ?u?niak, P.; Malka, J.; Nowak, R. J.; Pawlak, J. M.; Sztuk, J.; Tymieniecka, T.; Tyszkiewicz, A.; Ukleja, A.; Ukleja, J.; ?arnecki, A. F.; Adamus, M.; Plucinski, P.; Eisenberg, Y.; Hochman, D.; Karshon, U.; Lightwood, M. S.; Everett, A.; Kçira, D.; Lammers, S.; Li, L.; Reeder, D. D.; Rosin, M.; Ryan, P.; Savin, A. A.; Smith, W. H.; Dhawan, S.; Bhadra, S.; Catterall, C. D.; Cui, Y.; Hartner, G.; Menary, S.; Noor, U.; Soares, M.; Standage, J.; Whyte, J.

2006-01-01

296

Measurement of beauty production in deep inelastic scattering at HERA using decays into electrons  

Microsoft Academic Search

The production of beauty quarks in ep interactions has been studied with the ZEUS detector at HERA for exchanged four-momentum squared Q\\u000a 2>10 GeV2, using an integrated luminosity of 363?pb?1. The beauty events were identified using electrons from semileptonic b decays with a transverse momentum  GeV and pseudorapidity |?\\u000a \\u000a e\\u000a |<1.5. Cross sections for beauty production were measured and compared with

H. Abramowicz; I. Abt; L. Adamczyk; M. Adamus; R. Aggarwal; S. Antonelli; P. Antonioli; A. Antonov; M. Arneodo; V. Aushev; Y. Aushev; O. Bachynska; A. Bamberger; A. N. Barakbaev; G. Barbagli; G. Bari; F. Barreiro; N. Bartosik; D. Bartsch; M. Basile; O. Behnke; J. Behr; U. Behrens; L. Bellagamba; A. Bertolin; S. Bhadra; M. Bindi; C. Blohm; V. Bokhonov; T. Bold; O. Bolilyi; E. G. Boos; K. Borras; D. Boscherini; D. Bot; S. K. Boutle; I. Brock; E. Brownson; R. Brugnera; N. Brümmer; A. Bruni; G. Bruni; B. Brzozowska; P. J. Bussey; J. M. Butterworth; B. Bylsma; A. Caldwell; M. Capua; R. Carlin; C. D. Catterall; S. Chekanov; J. Chwastowski; J. Ciborowski; R. Ciesielski; L. Cifarelli; F. Cindolo; A. Contin; A. M. Cooper-Sarkar; N. Coppola; M. Corradi; F. Corriveau; M. Costa; G. D’Agostini; R. K. Dementiev; S. De Pasquale; M. Derrick; R. C. E. Devenish; D. Dobur; B. A. Dolgoshein; G. Dolinska; A. T. Doyle; V. Drugakov; L. S. Durkin; S. Dusini; Y. Eisenberg; P. F. Ermolov; A. Eskreys; S. Fang; S. Fazio; J. Ferrando; M. I. Ferrero; J. Figiel; M. Forrest; B. Foster; S. Fourletov; G. Gach; A. Galas; E. Gallo; A. Garfagnini; A. Geiser; I. Gialas; L. K. Gladilin; D. Gladkov; C. Glasman; O. Gogota; Y. A. Golubkov; P. Göttlicher; I. Grabowska-Bo?d; J. Grebenyuk; I. Gregor; G. Grigorescu; G. Grzelak; O. Gueta; C. Gwenlan; T. Haas; W. Hain; R. Hamatsu; J. C. Hart; H. Hartmann; G. Hartner; E. Hilger; D. Hochman; R. Hori; K. Horton; A. Hüttmann; G. Iacobucci; Z. A. Ibrahim; Y. Iga; R. Ingbir; M. Ishitsuka; H.-P. Jakob; F. Januschek; M. Jimenez; T. W. Jones; M. Jüngst; I. Kadenko; B. Kahle; B. Kamaluddin; S. Kananov; T. Kanno; U. Karshon; F. Karstens; I. I. Katkov; M. Kaur; P. Kaur; A. Keramidas; L. A. Khein; J. Y. Kim; D. Kisielewska; S. Kitamura; R. Klanner; U. Klein; E. Koffeman; P. Kooijman; I. Korol; I. A. Korzhavina; A. Kotanski; U. Kötz; H. Kowalski; P. Kulinski; O. Kuprash; M. Kuze; A. Lee; B. B. Levchenko; A. Levy; V. Libov; S. Limentani; T. Y. Ling; M. Lisovyi; E. Lobodzinska; W. Lohmann; B. Löhr; E. Lohrmann; J. H. Loizides; K. R. Long; A. Longhin; D. Lontkovskyi; O. Y. Lukina; P. ?u?niak; J. Maeda; S. Magill; I. Makarenko; J. Malka; R. Mankel; A. Margotti; G. Marini; J. F. Martin; A. Mastroberardino; M. C. K. Mattingly; I.-A. Melzer-Pellmann; S. Mergelmeyer; S. Miglioranzi; F. Mohamad Idris; V. Monaco; A. Montanari; J. D. Morris; K. Mujkic; B. Musgrave; K. Nagano; T. Namsoo; R. Nania; D. Nicholass; A. Nigro; Y. Ning; U. Noor; D. Notz; R. J. Nowak; A. E. Nuncio-Quiroz; B. Y. Oh; N. Okazaki; K. Oliver; K. Olkiewicz; Y. Onishchuk; K. Papageorgiu; A. Parenti; E. Paul; J. M. Pawlak; B. Pawlik; P. G. Pelfer; A. Pellegrino; W. Perlanski; H. Perrey; K. Piotrzkowski; P. Plucinski; N. S. Pokrovskiy; A. Polini; A. S. Proskuryakov; M. Przybycien; A. Raval; D. D. Reeder; B. Reisert; Z. Ren; J. Repond; Y. D. Ri; A. Robertson; P. Roloff; E. Ron; I. Rubinsky; M. Ruspa; R. Sacchi; A. Salii; U. Samson; G. Sartorelli; A. A. Savin; D. H. Saxon; M. Schioppa; S. Schlenstedt; P. Schleper; W. B. Schmidke; U. Schneekloth; V. Schönberg; T. Schörner-Sadenius; J. Schwartz; F. Sciulli; L. M. Shcheglova; R. Shehzadi; S. Shimizu; I. Singh; I. O. Skillicorn; W. Slominski; W. H. Smith; V. Sola; A. Solano; D. Son; V. Sosnovtsev; A. Spiridonov; H. Stadie; L. Stanco; A. Stern; T. P. Stewart; A. Stifutkin; P. Stopa; S. Suchkov; G. Susinno; L. Suszycki; J. Sztuk-Dambietz; D. Szuba; J. Szuba; A. D. Tapper; E. Tassi; J. Terrón; T. Theedt; H. Tiecke; K. Tokushuku; O. Tomalak; J. Tomaszewska; T. Tsurugai; M. Turcato; T. Tymieniecka; C. Uribe-Estrada; M. Vázquez; A. Verbytskyi; O. Viazlo; N. N. Vlasov; O. Volynets; R. Walczak; W. A. T. Wan Abdullah; J. J. Whitmore; J. Whyte; L. Wiggers; M. Wing; M. Wlasenko; G. Wolf; H. Wolfe; K. Wrona; A. G. Yagües-Molina; S. Yamada; Y. Yamazaki; R. Yoshida; C. Youngman; A. F. ?arnecki; L. Zawiejski; O. Zenaiev; W. Zeuner; B. O. Zhautykov; N. Zhmak; C. Zhou; A. Zichichi; M. Zolko; D. S. Zotkin; Z. Zulkapli

2011-01-01

297

Reactivity of whole coals, selected pure maceral fractions, and cleaned coal products: Final report, January 1--December 31, 1988  

SciTech Connect

A long-term program is currently underway to determine the process response properties of pure single coal maceral fractions in order to predict the behavior of various whole coals of different maceral compositions and rank. The primary objectives of the study are to: (1) evaluate the reactivity of whole coals and macerals from other seams, covering the same broad rank range studied in the first phase of the program; (2) assess the degree of applicability of predictive equations for coals in general; and (3) evaluate the combustion characteristics of clean coals. This year, Argonne Premium samples were examined, as well as a number of coals obtained from various points throughout the US and the world (SIU coals). The coals were examined to determine if the relationships developed last year could be extrapolated to a wider rank range and maceral composition than the Hartshorne coals used in the last year's study. Efforts continued on modeling of the data obtained last year. Three cleaned and feed samples were obtained from OTISCA, Inc. Also, three feed and cleaned coals were obtained from the Pittsburgh Energy Technology Center and prepared. These coals will also be tested in the coming year's test matrix. A series of supercritical extraction (SCE) products, as well as the feeds, have also been tested. These samples were used to examine the effect of thermal desulfurization processing on combustion properties. A set of 50 samples has been obtained from the Pennsylvania State University. Twenty-five of these samples are of a rank series from the Lower Kittaning seam and will be used to further test and develop previously defined relationships. A second series is a set of high-sulfur coals. 20 refs., 2 figs., 3 tabs.

Crelling, J.C.; Hippo, E.J.

1989-03-01

298

Early developmental exposure to benzodiazepine ligands alters brain levels of thiobarbituric acid-reactive products in young adult rats  

Microsoft Academic Search

Levels of thiobarbituric acid (TBA)-reactive material were measured in brain regions of 3–4 monthold rats following prenatal exposure to several benzodiazepine (BDZ) receptor ligands over gestational days 14–20. Prenatal exposure to diazepam (DZ) at 1.0 mg\\/kg\\/day markedly elevated levels of brain TBA-reactive material while exposure to a higher dose (2.5 mg\\/kg) induced a significant increase only in the hippocampus. Early

Rajesh C. Miranda; Joseph P. Wagner; Carol K. Kellogg

1989-01-01

299

Multi-Jet Production in Lepton-Proton Scattering with Next-To Order Accuracy  

NASA Astrophysics Data System (ADS)

I summarize the theoretical and experimental status of multijet production in DIS. I present the state-of-the-art theoretical predictions and compare those to the corresponding experimental results obtained by analysing the data collected by the H1 and ZEUS collaborations at HERA. I also show new predictions for three-jet event-shape distributions at the NLO accuracy.

Trócsányi, Z.

2006-04-01

300

MultiJet Production in Lepton-Proton Scattering with Next-To Order Accuracy  

Microsoft Academic Search

I summarize the theoretical and experimental status of multijet production in DIS. I present the state-of-the-art theoretical predictions and compare those to the corresponding experimental results obtained by analysing the data collected by the H1 and ZEUS collaborations at HERA. I also show new predictions for three-jet event-shape distributions at the NLO accuracy.

Z. Trócsányi

2006-01-01

301

Production of reactive oxygen species, gene expression, and enzymatic activity in quail subjected to acute heat stress.  

PubMed

The aim of the present study was to evaluate the effect of acute heat stress on the production of mitochondrial reactive oxygen species (ROS), the gene expression of the avian uncoupling protein (avUCP) and glutathione peroxidase (GPX 7), and the activity of the enzyme GPX in the liver of meat quail. Two groups of 15 meat quail (Coturnix coturnix japonica) that were 23 d of age were initially housed individually in metallic cages. A period of 7 d was provided for the 2 bird groups to adapt to the cages and to a thermoneutral environment at 25°C with 60% relative humidity. At 30 d of age, 15 quail were exposed to a heat stress (HS) treatment of 34°C for 24 h, humidity 60%, whereas control quail (n = 15) were kept at 25°C. To analyze the production of ROS, 4 quail from each treatment group were slaughtered, and their livers were collected for mitochondrial isolation and to measure the subsequent production of ROS by the mitochondria. Additionally, the livers of 6 animals from each treatment group were collected for total RNA extraction. The cDNA was amplified using primers specific for the target genes, and expression was analyzed using the real-time PCR reaction (qRT-PCR). Five animals from each treatment group were slaughtered to analyze glutathione peroxidase (GPx) activity, which was determined by using of hydrogen peroxide (H2O2), and based on measuring the amount nicotinamide adenine dinucleotide phosphate oxidized. A greater amount of mitochondrial ROS was found in HS animals (0.34 vs. 0.22 nm of ROS produced min(-1) · mg(-1) of protein, P < 0.05) for the reactions that contained only rotenone and in the reactions that were performed with rotenone and antimycin (0.31 vs. 0.23 nm of ROS produced min(-1) · mg(-1) of protein, P < 0.05). Concomitantly, the birds that were subjected to acute heat stress and had a greater amount of ROS production expressed less avUCP mRNA [0.75 arbitrary units (AU) vs. 0.87 AU, P < 0.05] and more GPX 7 mRNA (2.37 AU vs. 1.17 AU, P < 0.01). The HS quail displayed significantly greater GPx activity in their hepatocytes (47.8 vs. 39.6 nmol of NADPH oxidized per mg of protein per minute, P < 0.05). Thus, acute heat stress at 34°C for 24 h affects the production of mitochondrial ROS, the expression of avUCP and GPX 7 mRNA, and the activity of the GPx enzyme in the liver of meat quail. PMID:23148249

Del Vesco, A P; Gasparino, E

2012-11-12

302

Electromagnetic Scattering.  

National Technical Information Service (NTIS)

Contents: Scattering by nonspherical systems; Light scattering from colloidal spheres and cylinders; Multiple scattering from particles in the mie region; Inversion of light scattering data for the determination of spherical particle spectrum; Use of smal...

R. L. Rowell R. S. Stein

1967-01-01

303

Excitons emissions and Raman scattering of ZnO nanoparticles embedded in BaF2 matrices by reactive magnetron sputtering.  

PubMed

ZnO nanoparticles embedded in BaF2 matrix were fabricated by rf magnetic sputtering technology. The optical properties of high quality ZnO nanoparticles, thermally post treated in a N2 atmosphere, were investigated by temperature-dependence photoluminescence measurement. Free exciton and localized exciton were observed at the low temperature. Free exciton peak was at 3.374 eV and localized exciton peak was at 3.420 eV, dominating the PL spectrum at 77 K. Free exciton transition was observed at 3.310 eV at room temperature, whereas the localized exciton transition was at 3.378 eV. The multiple-phonon Raman scattering spectrum showed that ZnO nanoparticles embedded in BaF2 matrix had a large deformation energy originated from lattice mismatch between ZnO and BaF2 matrix. Analysis of the fitting results from the temperature dependence of FWHM of ZnO exciton illustrated that the large value of gamma(ph) was good qualitative agreement with the large deformation potential. PMID:22413302

Zang, C H; Su, J F; Liu, Y C; Tang, C J; Fang, S J; Zhang, D M; Zhang, Y S

2011-11-01

304

Differential sensitivity of human monocytes and macrophages to ANP: a role of intracellular pH on reactive oxygen species production through the phospholipase involvement  

Microsoft Academic Search

Atrial natriuretic peptide (ANP), a car- diovascular hormone, elicits different biological actions in the immune system. The aim of the present work was to study the effect of ANP on the intracellular pH (pHi) of human monocytes and macrophages and to investigate whether pHi changes could play a role on phospholipase activities and reactive oxygen species (ROS) production. Human macrophages

P. M. Baldini; P. De Vito; A. Martino; M. Fraziano; C. Grimaldi; P. Luly; F. Zalfa; V. Colizzi

2003-01-01

305

Nitrofurantoin-Stimulated Reactive Oxygen Species Production and Genotoxicity in Digestive Gland Microsomes and Cytosol of the Common Mussel ( Mytilus edulis L.)  

Microsoft Academic Search

The ability of nitrofurantoin (NF) to produce reactive oxygen species (ROS) was investigated in subcellular fractions of digestive gland of the mussel Mytilus edulis in terms of oxygen consumption and the formation of superoxide anion radical (O?2) (measured as SOD-sensitive cytochrome c reduction or SOD-sensitive .OH production), H2O2 (effects of catalase), and hydroxyl radical (.OH) (iron\\/EDTA-mediated oxidation of KMBA to

P. G. Martinez; G. W. Winston; C. Metashdickey; S. C. M. Ohara; D. R. Livingstone

1995-01-01

306

Modification of production of reactive oxygen species in mouse peritoneal neutrophils on exposure to low-intensity modulated millimeter wave radiation  

Microsoft Academic Search

The effect of low-intensity modulated electromagnetic radiation of extremely high frequencies (EHF EMR) on the production of reactive oxygen species by mouse peritoneal neutrophils was investigated. The neutrophil activity in synergistic reaction of calcium ionophore A23187 and phorbol ester PMA was estimated by luminol-dependent chemiluminescence technique. The cells were irradiated for 20 min in the far-field zone of the channel

A. B Gapeyev; V. S Yakushina; N. K Chemeris; E. E Fesenko

1998-01-01

307

Solvent-refined-coal (SRC) process: reactivity of SRC-II liquefaction products. Interim report No. 69. [Experiments for model validation  

Microsoft Academic Search

Data from experimental studies of the reactivities of SRC-II liquefaction products, in the absence of coal, are analyzed. A quantitative validation of essential features of the new kinetic model for SRC-II coal-liquefaction is obtained by very good agreements between model predicted and measured yields. Validation of the proposed zero order rate mechanism for SRC conversion is tentative in this work,

C. P. P. Singh; N. L. Carr

1982-01-01

308

In Vivo and In Vitro Effects of Metals in Reactive Oxygen Species Production, Protein Carbonylation, and DNA Damage in Land Snails Eobania vermiculata  

Microsoft Academic Search

Heavy metals are known to induce oxidative damage by way of enhancement of intracellular reactive oxygen species (ROS) production,\\u000a which often preludes the onset of alterations, such as protein carbonylation and DNA damage. In this study, our aim was to\\u000a examine the early responses of land snails Eobania vermiculata to environmental contaminants by investigating the use of a modified enzyme-linked

A. Itziou; M. Kaloyianni; V. K. Dimitriadis

2011-01-01

309

The flavonoid dioclein reduces the production of pro-inflammatory mediators in vitro by inhibiting PDE4 activity and scavenging reactive oxygen species  

Microsoft Academic Search

Reactive oxygen species, cytokines and chemokines produced at inflammatory sites are pivotal events in the progression of many diseases. Flavonoids are well-known for their antioxidant and anti-inflammatory activities. Here, we investigated the effects of the flavonoid dioclein on the production of mediators of inflammation in vitro and possible underlying mechanisms. Murine macrophages were pretreated with dioclein, rolipram, a PDE4 (cyclic

Rodrigo Guabiraba; Ana Lucia Campanha-Rodrigues; Adriano L. S. Souza; Helton C. Santiago; Claire Lugnier; Jacqueline Alvarez-Leite; Virginia S. Lemos; Mauro M. Teixeira

2010-01-01

310

Interleukin6 Is a Better Predictor of Mortality as Compared to C-Reactive Protein, Homocysteine, Pentosidine and Advanced Oxidation Protein Products in Hemodialysis Patients  

Microsoft Academic Search

Inflammatory markers predict mortality in hemodialysis (HD) patients, whereas a possible association between oxidative stress (OS) markers and survival is less clear. We assessed the impact on all-cause mortality of baseline inflammatory [high-sensitivity C-reactive protein and interleukin-6 (IL-6)] and OS markers (advanced oxidation protein products, pentosidine, homocysteine) in 112 HD patients. We found no significant correlations between inflammatory and OS

Maria A. Pachaly; Marcelo M. do Nascimento; Mohamed E. Suliman; Shirley Y. Hayashi; Miguel C. Riella; Roberto C. Manfro; Peter Stenvinkel; Bengt Lindholm

2008-01-01

311

Measurement of beauty production in deep inelastic scattering at HERA using decays into electrons  

NASA Astrophysics Data System (ADS)

The production of beauty quarks in ep interactions has been studied with the ZEUS detector at HERA for exchanged four-momentum squared Q 2>10 GeV2, using an integrated luminosity of 363 pb-1. The beauty events were identified using electrons from semileptonic b decays with a transverse momentum 0.9 < pTe < 8 GeV and pseudorapidity | ? e |<1.5. Cross sections for beauty production were measured and compared with next-to-leading-order QCD calculations. The beauty contribution to the proton structure function F 2 was extracted from the double-differential cross section as a function of Bjorken- x and Q 2.

Abramowicz, H.; Abt, I.; Adamczyk, L.; Adamus, M.; Aggarwal, R.; Antonelli, S.; Antonioli, P.; Antonov, A.; Arneodo, M.; Aushev, V.; Aushev, Y.; Bachynska, O.; Bamberger, A.; Barakbaev, A. N.; Barbagli, G.; Bari, G.; Barreiro, F.; Bartosik, N.; Bartsch, D.; Basile, M.; Behnke, O.; Behr, J.; Behrens, U.; Bellagamba, L.; Bertolin, A.; Bhadra, S.; Bindi, M.; Blohm, C.; Bokhonov, V.; Bo?d, T.; Bolilyi, O.; Boos, E. G.; Borras, K.; Boscherini, D.; Bot, D.; Boutle, S. K.; Brock, I.; Brownson, E.; Brugnera, R.; Brümmer, N.; Bruni, A.; Bruni, G.; Brzozowska, B.; Bussey, P. J.; Butterworth, J. M.; Bylsma, B.; Caldwell, A.; Capua, M.; Carlin, R.; Catterall, C. D.; Chekanov, S.; Chwastowski, J.; Ciborowski, J.; Ciesielski, R.; Cifarelli, L.; Cindolo, F.; Contin, A.; Cooper-Sarkar, A. M.; Coppola, N.; Corradi, M.; Corriveau, F.; Costa, M.; D'Agostini, G.; Dal Corso, F.; del Peso, J.; Dementiev, R. K.; De Pasquale, S.; Derrick, M.; Devenish, R. C. E.; Dobur, D.; Dolgoshein, B. A.; Dolinska, G.; Doyle, A. T.; Drugakov, V.; Durkin, L. S.; Dusini, S.; Eisenberg, Y.; Ermolov, P. F.; Eskreys, A.; Fang, S.; Fazio, S.; Ferrando, J.; Ferrero, M. I.; Figiel, J.; Forrest, M.; Foster, B.; Fourletov, S.; Gach, G.; Galas, A.; Gallo, E.; Garfagnini, A.; Geiser, A.; Gialas, I.; Gladilin, L. K.; Gladkov, D.; Glasman, C.; Gogota, O.; Golubkov, Y. A.; Göttlicher, P.; Grabowska-Bo?d, I.; Grebenyuk, J.; Gregor, I.; Grigorescu, G.; Grzelak, G.; Gueta, O.; Gwenlan, C.; Haas, T.; Hain, W.; Hamatsu, R.; Hart, J. C.; Hartmann, H.; Hartner, G.; Hilger, E.; Hochman, D.; Hori, R.; Horton, K.; Hüttmann, A.; Iacobucci, G.; Ibrahim, Z. A.; Iga, Y.; Ingbir, R.; Ishitsuka, M.; Jakob, H.-P.; Januschek, F.; Jimenez, M.; Jones, T. W.; Jüngst, M.; Kadenko, I.; Kahle, B.; Kamaluddin, B.; Kananov, S.; Kanno, T.; Karshon, U.; Karstens, F.; Katkov, I. I.; Kaur, M.; Kaur, P.; Keramidas, A.; Khein, L. A.; Kim, J. Y.; Kisielewska, D.; Kitamura, S.; Klanner, R.; Klein, U.; Koffeman, E.; Kooijman, P.; Korol, I.; Korzhavina, I. A.; Kota?ski, A.; Kötz, U.; Kowalski, H.; Kulinski, P.; Kuprash, O.; Kuze, M.; Lee, A.; Levchenko, B. B.; Levy, A.; Libov, V.; Limentani, S.; Ling, T. Y.; Lisovyi, M.; Lobodzinska, E.; Lohmann, W.; Löhr, B.; Lohrmann, E.; Loizides, J. H.; Long, K. R.; Longhin, A.; Lontkovskyi, D.; Lukina, O. Y.; ?u?niak, P.; Maeda, J.; Magill, S.; Makarenko, I.; Malka, J.; Mankel, R.; Margotti, A.; Marini, G.; Martin, J. F.; Mastroberardino, A.; Mattingly, M. C. K.; Melzer-Pellmann, I.-A.; Mergelmeyer, S.; Miglioranzi, S.; Mohamad Idris, F.; Monaco, V.; Montanari, A.; Morris, J. D.; Mujkic, K.; Musgrave, B.; Nagano, K.; Namsoo, T.; Nania, R.; Nicholass, D.; Nigro, A.; Ning, Y.; Noor, U.; Notz, D.; Nowak, R. J.; Nuncio-Quiroz, A. E.; Oh, B. Y.; Okazaki, N.; Oliver, K.; Olkiewicz, K.; Onishchuk, Y.; Papageorgiu, K.; Parenti, A.; Paul, E.; Pawlak, J. M.; Pawlik, B.; Pelfer, P. G.; Pellegrino, A.; Perlanski, W.; Perrey, H.; Piotrzkowski, K.; Plucinski, P.; Pokrovskiy, N. S.; Polini, A.; Proskuryakov, A. S.; Przybycie?, M.; Raval, A.; Reeder, D. D.; Reisert, B.; Ren, Z.; Repond, J.; Ri, Y. D.; Robertson, A.; Roloff, P.; Ron, E.; Rubinsky, I.; Ruspa, M.; Sacchi, R.; Salii, A.; Samson, U.; Sartorelli, G.; Savin, A. A.; Saxon, D. H.; Schioppa, M.; Schlenstedt, S.; Schleper, P.; Schmidke, W. B.; Schneekloth, U.; Schönberg, V.; Schörner-Sadenius, T.; Schwartz, J.; Sciulli, F.; Shcheglova, L. M.; Shehzadi, R.; Shimizu, S.; Singh, I.; Skillicorn, I. O.; S?omi?ski, W.; Smith, W. H.; Sola, V.; Solano, A.; Son, D.; Sosnovtsev, V.; Spiridonov, A.; Stadie, H.; Stanco, L.; Stern, A.; Stewart, T. P.; Stifutkin, A.; Stopa, P.; Suchkov, S.; Susinno, G.; Suszycki, L.; Sztuk-Dambietz, J.; Szuba, D.; Szuba, J.; Tapper, A. D.; Tassi, E.; Terrón, J.; Theedt, T.; Tiecke, H.; Tokushuku, K.; Tomalak, O.; Tomaszewska, J.; Tsurugai, T.; Turcato, M.; Tymieniecka, T.; Uribe-Estrada, C.; Vázquez, M.; Verbytskyi, A.; Viazlo, O.; Vlasov, N. N.; Volynets, O.; Walczak, R.; Wan Abdullah, W. A. T.; Whitmore, J. J.; Whyte, J.; Wiggers, L.; Wing, M.; Wlasenko, M.; Wolf, G.; Wolfe, H.; Wrona, K.; Yagües-Molina, A. G.; Yamada, S.; Yamazaki, Y.; Yoshida, R.; Youngman, C.; ?arnecki, A. F.; Zawiejski, L.; Zenaiev, O.; Zeuner, W.; Zhautykov, B. O.; Zhmak, N.; Zhou, C.; Zichichi, A.; Zolko, M.; Zotkin, D. S.; Zulkapli, Z.

2011-02-01

312

Multijet production in lepton-proton scattering at next-to-leading order accuracy  

Microsoft Academic Search

I summarize the theoretical and experimental status of multijet production in\\u000aDIS. I present the state of the art theoretical predictions and compare those\\u000ato the corresponding experimental results obtained by analysing the data\\u000acollected by the H1 and ZEUS collaborations at HERA. I also show new\\u000apredictions for three-jet event-shape distributions at the NLO accuracy.

Z. Trocsanyi

2005-01-01

313

Diffractive open charm production in deep-inelastic scattering and photoproduction at HERA  

Microsoft Academic Search

Measurements are presented of diffractive open charm production at HERA. The event topology is given by ep?eXY where the system\\u000a X contains at least one charmed hadron and is well separated by a large rapidity gap from a leading low-mass proton remnant\\u000a system Y. Two analysis techniques are used for the cross section measurements. In the first, the charm quark

A. Aktas; V. Andreev; T. Anthonis; B. Antunovic; S. Aplin; A. Astvatsatourov; A. Baghdasaryan; S. Backovic; P. Baranov; E. Barrelet; W. Bartel; S. Baudrand; M. Beckingham; K. Begzsuren; O. Behnke; O. Behrendt; A. Belousov; N. Berger; J. C. Bizot; M.-O. Boenig; V. Boudry; I. Bozovic-Jelisavcic; J. Bracinik; G. Brandt; M. Brinkmann; V. Brisson; D. Bruncko; F. W. Büsser; A. Bunyatyan; G. Buschhorn; L. Bystritskaya; A. J. Campbell; K. B. Cantun Avila; F. Cassol-Brunner; K. Cerny; V. Cerny; V. Chekelian; J. G. Contreras; J. A. Coughlan; B. E. Cox; G. Cozzika; J. Cvach; J. B. Dainton; K. Daum; Y. de Boer; B. Delcourt; M. Del Degan; A. De Roeck; E. A. De Wolf; C. Diaconu; V. Dodonov; A. Dubak; G. Eckerlin; V. Efremenko; S. Egli; R. Eichler; F. Eisele; A. Eliseev; E. Elsen; S. Essenov; A. Falkewicz; P. J. W. Faulkner; L. Favart; A. Fedotov; R. Felst; J. Feltesse; J. Ferencei; L. Finke; M. Fleischer; G. Flucke; A. Fomenko; G. Franke; T. Frisson; E. Gabathuler; E. Garutti; J. Gayler; S. Ghazaryan; S. Ginzburgskaya; A. Glazov; I. Glushkov; L. Goerlich; M. Goettlich; N. Gogitidze; S. Gorbounov; M. Gouzevitch; C. Grab; T. Greenshaw; M. Gregori; B. R. Grell; G. Grindhammer; C. Gwilliam; S. Habib; D. Haidt; M. Hansson; G. Heinzelmann; C. Helebrant; R. C. W. Henderson; H. Henschel; G. Herrera; M. Hildebrandt; K. H. Hiller; D. Hoffmann; R. Horisberger; A. Hovhannisyan; T. Hreus; S. Hussain; M. Ibbotson; M. Jacquet; X. Janssen; V. Jemanov; L. Jönsson; D. P. Johnson; A. W. Jung; H. Jung; M. Kapichine; J. Katzy; I. R. Kenyon; C. Kiesling; M. Klein; C. Kleinwort; T. Klimkovich; T. Kluge; G. Knies; A. Knutsson; V. Korbel; P. Kostka; M. Kraemer; K. Krastev; J. Kretzschmar; A. Kropivnitskaya; K. Krüger; M. P. J. Landon; W. Lange; G. Lastovicka-Medin; P. Laycock; A. Lebedev; G. Leibenguth; V. Lendermann; S. Levonian; L. Lindfeld; K. Lipka; A. Liptaj; B. List; J. List; N. Loktionova; R. Lopez-Fernandez; V. Lubimov; A.-I. Lucaci-Timoce; H. Lueders; L. Lytkin; A. Makankine; E. Malinovski; P. Marage; R. Marshall; L. Marti; M. Martisikova; H.-U. Martyn; S. J. Maxfield; A. Mehta; K. Meier; A. B. Meyer; H. Meyer; J. Meyer; V. Michels; S. Mikocki; I. Milcewicz-Mika; D. Mladenov; A. Mohamed; F. Moreau; A. Morozov; J. V. Morris; M. U. Mozer; K. Müller; P. Murín; K. Nankov; B. Naroska; T. Naumann; P. R. Newman; C. Niebuhr; A. Nikiforov; G. Nowak; K. Nowak; M. Nozicka; R. Oganezov; B. Olivier; J. E. Olsson; S. Osman; D. Ozerov; V. Palichik; I. Panagoulias; M. Pandurovic; T. Papadopoulou; C. Pascaud; G. D. Patel; H. Peng; E. Perez; D. Perez-Astudillo; A. Perieanu; A. Petrukhin; I. Picuric; S. Piec; D. Pitzl; R. Placakyte; B. Povh; P. Prideaux; A. J. Rahmat; N. Raicevic; P. Reimer; A. Rimmer; C. Risler; E. Rizvi; P. Robmann; B. Roland; R. Roosen; A. Rostovtsev; Z. Rurikova; S. Rusakov; F. Salvaire; D. P. C. Sankey; M. Sauter; E. Sauvan; S. Schmidt; S. Schmitt; C. Schmitz; L. Schoeffel; A. Schöning; H.-C. Schultz-Coulon; F. Sefkow; R. N. Shaw-West; I. Sheviakov; L. N. Shtarkov; T. Sloan; I. Smiljanic; P. Smirnov; Y. Soloviev; D. South; V. Spaskov; A. Specka; M. Steder; B. Stella; J. Stiewe; A. Stoilov; U. Straumann; D. Sunar; T. Sykora; V. Tchoulakov; G. Thompson; P. D. Thompson; T. Toll; F. Tomasz; D. Traynor; T. N. Trinh; P. Truöl; I. Tsakov; G. Tsipolitis; I. Tsurin; J. Turnau; E. Tzamariudaki; K. Urban; M. Urban; A. Usik; D. Utkin; A. Valkárová; C. Vallée; P. Van Mechelen; A. Vargas Trevino; Y. Vazdik; S. Vinokurova; V. Volchinski; K. Wacker; G. Weber; R. Weber; D. Wegener; C. Werner; M. Wessels; C. Wissing; R. Wolf; E. Wünsch; S. Xella; W. Yan; V. Yeganov; J. Žá?ek; J. Zálesák; Z. Zhang; A. Zhelezov; A. Zhokin; Y. C. Zhu; J. Zimmermann; T. Zimmermann; H. Zohrabyan; F. Zomer

2007-01-01

314

Elastic scattering and particle production in two-prong. pi. /sup -/p interactions at 8 GeV/c  

SciTech Connect

Results of a high-statistics study of elastic scattering and meson resonances produced by ..pi../sup -/p interactions at 8 GeV/c are presented. Large statistics and small systematic errors permit examination of the complete kinematic region. Total differential cross sections are given for rho/sup 0,-/, f/sup 0/, g/sup 0,-/, ..delta../sup + -/, ..delta../sup 0/, and N* resonances. Spin-density matrix elements and Legendre-polynomial moments are given for rho, f, and ..delta.. resonances. The results for rho/sup 0/ and f/sup 0/ resonances are compared with the predictions of a Regge-pole-exchange model. Properties of the above resonances are compared and discussed. In particular, we present evidence that the rho/sup 0/ and f/sup 0/ production mechanisms are similar. The similarity of the g/sup 0/ t distribution to that of the rho/sup 0/ and f/sup 0/ suggests a common production mechanism for all three resonances.

Kitagaki, T.; Tanaka, S.; Yuta, H.; Abe, K.; Hasegawa, K.; Yamaguchi, A.; Nozaki, T.; Tamai, K.; Maruyama, T.; Kikuchi, R.; Unno, Y.; Otani, Y.; Barreiro, F.; Benary, O.; Brau, J.E.; Dolfini, R.; Hafen, E.S.; Haridas, P.; Hochman, D.; Hodous, M.F.; Hulsizer, R.I.; Kistiakowsky, V.; Napier, A.; Noguchi, S.; Oh, S.H.; Pless, I.A.; Silverman, J.P.; Trepagnier, P.C.; Wolfson, J.; Wu, Y.; Yamamoto, R.K.; Cohn, H.O.; Bugg, W.M.; Condo, G.T.; Handler, T.; Hart, E.L.

1982-10-01

315

On the recuperation and production of electricity from scattered sources of energy  

NASA Astrophysics Data System (ADS)

Massive production of electricity from renewable sources encounters a number of complications. Thus, among the various ways of transforming solar radiation into electricity would be to heat compressed air as directly as possible for expansion. Employing a regular steam cycle is complicated and incurs high-maintenance costs. Stabilizing a delicate influx of energy from solar, winds, and wave sources is resolved similarly to computer processing with component of different productivities, namely with buffering and pipelining. Actually, the pipelining scheme for heating the air is somehow used to make the heating process more thermodynamically efficient. However, because of timing misbalance it may contribute to the temporal variations of the main working cycle. All these temporal variations problems can be handled by ``buffering'' scheme, in the way similar to processing of intensive information flows with relatively slow computers. Most effective embodiment of this scheme would be generating electricity from the surf waves as they do not suffer from intermittent interruptions. This can be done for storing and recuperation enhancement of energy by using liquid nitrogen.

Berkovich, Simon

2010-03-01

316

Black tattoo inks induce reactive oxygen species production correlating with aggregation of pigment nanoparticles and product brand but not with the polycyclic aromatic hydrocarbon content.  

PubMed

Black tattoo inks are composed of carbon nanoparticles, additives and water and may contain polycyclic aromatic hydrocarbons (PAHs). We aimed to clarify whether reactive oxygen species (ROS) induced by black inks in vitro is related to pigment chemistry, physico-chemical properties of the ink particles and the content of chemical additives and contaminants including PAHs. The study included nine brands of tattoo inks of six colours each (black, red, yellow, blue, green and white) and two additional black inks of different brands (n = 56). The ROS formation potential was determined by the dichlorofluorescein (DCFH) assay. A semiquantitative method was developed for screening extractable organic compounds in tattoo ink based on gas chromatography-mass spectrometry (GC-MS) and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS). Two black inks produced high amounts of ROS. Peroxyl radicals accounted for up to 72% of the free radicals generated, whereas hydroxyl radicals and H?O? accounted for <14% and 16%, respectively. The same two inks aggregated strongly in water in contrast to the other black inks. They did not exhibit any shared pattern in PAHs and other organic substances. Aggregation was exclusively shared by all ink colours belonging to the same two brands. Ten of 11 black inks had PAH concentrations exceeding the European Council's recommended level, and all 11 exceeded the recommended level for benzo(a)pyrene. It is a new finding that aggregation of tattoo pigment particles correlates with ROS production and brand, independently of chemical composition including PAHs. ROS is hypothesized to be implicated in minor clinical symptoms. PMID:23800057

Høgsberg, Trine; Jacobsen, Nicklas Raun; Clausen, Per Axel; Serup, Jørgen

2013-07-01

317

Activation of CaMKII as a key regulator of reactive oxygen species production in diabetic rat heart.  

PubMed

Diabetes mellitus is a risk factor for heart failure. Increased reactive oxygen species (ROS) have been proposed as a possible mechanism of cardiac dysfunction in diabetic patients. However, the mechanisms of ROS increase are still elusive. We hypothesized that activation of Ca(2+)/calmodulin-dependent protein kinase II (CaMKII) induced by impaired intracellular Ca(2+) ([Ca(2+)](i)) metabolism may stimulate ROS production in the diabetic heart. Cultured cardiomyocytes from neonatal rats were exposed to high glucose concentrations (25 mmol/L) and ROS levels were analyzed in 5-(and-6)-chloromethyl-2',7'-dichlorodihydrofluorescein diacetate, acetyl ester (CM-H(2)DCFDA)-loaded cells by flow cytometry analysis. Exposure to high glucose concentrations for 24h significantly increased CM-H(2)DCFDA fluorescence, which was significantly inhibited by 1,2-bis (o-aminophenoxy) ethane- N,N,N',N'-tetraacetic acid tetraacetoxymethyl ester (BAPTA-AM), a [Ca(2+)](i) chelator, and KB-R7943, an inhibitor of the Na(+)-Ca(2+) exchanger (NCX) in the reverse mode. These results indicate that [Ca(2+)](i) increase by NCX activation may induce ROS increase following exposure to high glucose concentrations. We confirmed that exposure to high glucose concentrations significantly increased [Ca(2+)](i), which was inhibited by KB-R7943. Na(+)-H(+) exchanger (NHE) is a key factor in [Ca(2+)](i) metabolism, and is known to activate NCX by increasing the intracellular Na(+) ([Na(+)](i)) level. We showed that the expression of NHE isoform 1 and NHE activity increased following exposure to high glucose concentrations by evaluating protein expressions and intracellular pH recovery from acid loading. Exposure to high glucose concentrations up-regulated phosphorylated CaMKII expression in cardiomyocytes that was inhibited by KB-R7943. Further, autocamtide 2-related inhibitory peptide (AIP), a CaMKII inhibitor, significantly attenuated the ROS increase following exposure to high glucose concentrations. We confirmed these results obtained in in vitro experiments in an animal model of diabetes. ROS level and components of NADPH oxidase, p47phox and p67phox were up-regulated in streptozotocin-induced diabetic rat heart, which were attenuated by KN-93, a CaMKII inhibitor. Consistently, expression of phosphorylated CaMKII was increased in the diabetic heart. Activation of CaMKII by impaired [Ca(2+)](i) metabolism may be a mechanism of ROS increase in the heart with diabetes mellitus. PMID:22394624

Nishio, Satoru; Teshima, Yasushi; Takahashi, Naohiko; Thuc, Luong Cong; Saito, Shotaro; Fukui, Akira; Kume, Osamu; Fukunaga, Naoya; Hara, Masahide; Nakagawa, Mikiko; Saikawa, Tetsunori

2012-02-25

318

Aging Enhances the Production of Reactive Oxygen Species and Bactericidal Activity in Peritoneal Macrophages by Upregulating Classical Activation Pathways  

SciTech Connect

Maintenance of macrophages in their basal state and their rapid activation in response to pathogen detection are central to the innate immune system, acting to limit nonspecific oxidative damage and promote pathogen killing following infection. To identify possible age-related alterations in macrophage function, we have assayed the function of peritoneal macrophages from young (3?4 months) and aged (14?15 months) Balb/c mice. In agreement with prior suggestions, we observe age-dependent increases in the extent of recruitment of macrophages into the peritoneum, as well as ex vivo functional changes involving enhanced nitric oxide production under resting conditions that contribute to a reduction in the time needed for full activation of senescent macrophages following exposure to lipopolysaccharides (LPS). Further, we observe enhanced bactericidal activity following Salmonella uptake by macrophages isolated from aged Balb/c mice in comparison with those isolated from young animals. Pathways responsible for observed phenotypic changes were interrogated using tandem mass spectrometry, which identified age-dependent increases in levels of proteins linked to immune cell pathways under basal conditions and following LPS activation. Immune pathways upregulated in macrophages isolated from aged mice include proteins critical to the formation of the immunoproteasome. Detection of these latter proteins is dramatically enhanced following LPS exposure for macrophages isolated from aged animals; in comparison, the identification of immunoproteasome subunits is insensitive to LPS exposure for macrophages isolated from young animals. Consistent with observed global changes in the proteome, quantitative proteomic measurements indicate that there are age-dependent abundance changes involving specific proteins linked to immune cell function under basal conditions. LPS exposure selectively increases the levels of many proteins involved in immune cell function in aged Balb/c mice. Collectively, these results indicate that macrophages isolated from old mice are in a preactivated state that enhances their sensitivities to LPS exposure. The hyper-responsive activation of macrophages in aged animals may act to minimize infection by general bacterial threats that arise due to age-dependent declines in adaptive immunity. However, this hypersensitivity and the associated increase in the level of formation of reactive oxygen species are likely to contribute to observed age-dependent increases in the level of oxidative damage that underlie many diseases of the elderly.

Smallwood, Heather S.; Lopez-Ferrer, Daniel; Squier, Thomas C.

2011-10-07

319

Contribution of the FAD and quinone binding sites to the production of reactive oxygen species from Ascaris suum mitochondrial complex II.  

PubMed

Reactive oxygen species (ROS) production from mitochondrial complex II (succinate-quinone reductase, SQR) has become a focus of research recently since it is implicated in carcinogenesis. To date, the FAD site is proposed as the ROS producing site in complex II, based on studies done on Escherichia coli, whereas the quinone binding site is proposed as the site of ROS production based on studies in Saccharomyces cerevisiae. Using the submitochondrial particles from the adult worms and L(3) larvae of the parasitic nematode Ascaris suum, we found that ROS are produced from more than one site in the mitochondrial complex II. Moreover, the succinate-dependent ROS production from the complex II of the A. suum adult worm was significantly higher than that from the complex II of the L(3) larvae. Considering the conservation of amino acids crucial for the SQR activity and the high levels of ROS production from the mitochondrial complex II of the A. suum adult worm together with the absence of complexes III and IV activities in its respiratory chain, it is a good model to examine the reactive oxygen species production from the mitochondrial complex II. PMID:20006739

Paranagama, Madhavi P; Sakamoto, Kimitoshi; Amino, Hisako; Awano, Mutsumi; Miyoshi, Hideto; Kita, Kiyoshi

2009-12-16

320

Production of reactive oxygen species by isolated mitochondria of the Antarctic bivalve Laternula elliptica (King and Broderip) under heat stress  

Microsoft Academic Search

Formation of reactive oxygen species (ROS) in mitochondrial isolates from gill tissues of the Antarctic polar bivalve Laternula elliptica was measured fluorimetrically under in vitro conditions. When compared to the rates measured at habitat temperature (1 °C), significantly elevated ROS formation was found under temperature stress of 7 °C and higher. ROS formation correlated significantly with oxygen consumption in individual

K. Heise; S. Puntarulo; H. O. Portner; D. Abele

2003-01-01

321

Multivariate Hermite interpolation on scattered point sets using tensor-product expo-rational B-splines  

NASA Astrophysics Data System (ADS)

At the Seventh International Conference on Mathematical Methods for Curves and Surfaces, Tønsberg, Norway, in 2008, several new constructions for Hermite interpolation on scattered point sets in domains in Rn,n\\isinv N, combined with smooth convex partition of unity for several general types of partitions of these domains were proposed in [1]. All of these constructions were based on a new type of B-splines, proposed by some of the authors several years earlier: expo-rational B-splines (ERBS) [3]. In the present communication we shall provide more details about one of these constructions: the one for the most general class of domain partitions considered. This construction is based on the use of two separate families of basis functions: one which has all the necessary Hermite interpolation properties, and another which has the necessary properties of a smooth convex partition of unity. The constructions of both of these two bases are well-known the new part of the construction is the combined use of these bases for the derivation of a new basis which enjoys having all above-said interpolation and unity partition properties simultaneously. In [1] the emphasis was put on the use of radial basis functions in the definitions of the two initial bases in the construction; now we shall put the main emphasis on the case when these bases consist of tensor-product B-splines. This selection provides two useful advantages: (A) it is easier to compute higher-order derivatives while working in Cartesian coordinates; (B) it becomes clear that this construction becomes a far-going extension of tensor-product constructions. We shall provide 3-dimensional visualization of the resulting bivariate bases, using tensor-product ERBS. In the main tensor-product variant, we shall consider also replacement of ERBS with simpler generalized ERBS (GERBS) [2], namely, their simplified polynomial modifications: the Euler Beta-function B-splines (BFBS). One advantage of using BFBS instead of ERBS is the simplified computation, since BFBS are piecewise polynomial, which ERBS are not. One disadvantage of using BFBS in the place of ERBS in this construction is that the necessary selection of the degree of BFBS imposes constraints on the maximal possible multiplicity of the Hermite interpolation.

Dechevsky, Lubomir T.; Bang, Børre; Laksa?, Arne; Zanaty, Peter

2011-12-01

322

Rayleigh Scattering.  

ERIC Educational Resources Information Center

|The correct usage of such terminology as "Rayleigh scattering,""Rayleigh lines,""Raman lines," and "Tyndall scattering" is resolved during an historical excursion through the physics of light-scattering by gas molecules. (Author/JN)|

Young, Andrew T.

1982-01-01

323

Rayleigh Scattering.  

ERIC Educational Resources Information Center

The correct usage of such terminology as "Rayleigh scattering,""Rayleigh lines,""Raman lines," and "Tyndall scattering" is resolved during an historical excursion through the physics of light-scattering by gas molecules. (Author/JN)

Young, Andrew T.

1982-01-01

324

Pyruvate: immunonutritional effects on neutrophil intracellular amino or alpha-keto acid profiles and reactive oxygen species production  

Microsoft Academic Search

For the first time the immunonutritional role of pyruvate on neutrophils (PMN), free ?-keto and amino acid profiles, important\\u000a reactive oxygen species (ROS) produced [superoxide anion (O2\\u000a ?), hydrogen peroxide (H2O2)] as well as released myeloperoxidase (MPO) acitivity has been investigated. Exogenous pyruvate significantly increased PMN\\u000a pyruvate, ?-ketoglutarate, asparagine, glutamine, aspartate, glutamate, arginine, citrulline, alanine, glycine and serine\\u000a in a

D. Mathioudakis; J. Engel; I. D. Welters; M. G. Dehne; R. Matejec; H. Harbach; M. Henrich; T. Schwandner; M. Fuchs; K. Weismüller; G. J. Scheffer; Jörg Mühling

2011-01-01

325

RETRACTED ARTICLE: Kinetic and anion degradation products study on photocatalytic degradation of reactive orange 5 solution with phosphotungstic acid  

Microsoft Academic Search

Increasing environmental pollution caused by toxic dyes is a matter of great concern due to their hazardous nature. So it\\u000a is crucial to develop processes which can destroy these dyes effectively. It has been generally agreed that reactive orange\\u000a 5 (KGN) can be effectively degraded in aerated phosphotungstic acid (HPA) in a homogeneous reaction system using near-UV irradiation.\\u000a In this

Junbo Zhong; Hong Zhao; Di Ma; An Lian; Minjiao Li; Bin Xie; Jianzhang Li

2008-01-01

326

Moderators of cardiovascular reactivity to speech: discourse production and group variations in blood pressure and pulse rate  

Microsoft Academic Search

To explain why speech produces cardiovascular reactivity, an experiment utilized speech tasks varying in self-disclosure and cognitive preparation and measured the blood pressure and pulse rate of African-American and Caucasian, men and women subjects. One hundred and fifty-six college students with a median age of 21 volunteered to participate. The extemporaneous speech task produced lower systolic blood pressure than the

C. H. Tardy; M. T. Allen

1998-01-01

327

ESR Study in Reactive Oxygen Species Free Radical Production of Pinus kesiya var. langbianensis Heartwood Treated with Laccase  

Microsoft Academic Search

.  Enzymatic oxidation of lignin phenolic hydroxyl groups can enhance the level of autoadhesion between wood fibers or particles\\u000a depending upon the bonding mechanism of wood-based materials without synthetic adhesives such as urea and phenol formaldehyde.\\u000a The adhesive effect is caused by an increased number of reactive oxygen groups at the fiber surface. The parameters of laccase-treated\\u000a wood fibers play vital

Y. J. Cao; X. F. Duan; Y. L. Cao; J. X. Lü; J. Q. Zhu; G. W. Zhou; B. L. Zhao

2008-01-01

328

The Ozone Productivity of n-Propyl Bromide: Part 2—An Exception to the Maximum Incremental Reactivity Scale  

Microsoft Academic Search

In an earlier paper the ozone-forming potential of n-propyl bromide (NPB) was studied with a new methodology designed to address issues associated with a marginal smog-forming compound. However, the U.S. Environmental Protection Agency (EPA) subsequently revised its policy and now recommends using the Maximum Incremental Reactivity (MIR) scale to rank the ozone-forming potential of all volatile organic compounds (VOCs), including

Gary Z. Whitten; Greg Yarwood; Sunhee Lee; Kevin Tory; Dale Hess; Manuela Burgers; Bill Lilley; Richard Baldauf; Eben Thoma; Michael Hays; Richard Shores; John Kinsey; Brian Gullett; Sue Kimbrough; Vlad Isakov; Thomas Long; Richard Snow; Andrey Khlystov; Jason Weinstein; Fu-Lin Chen; Robert Seila; David Olson; Ian Gilmour; Seung-Hyun Cho; Nealson Watkins; Patricia Rowley; Marc Carreras-Sospedra; Donald Dabdub; Jacob Brouwer; Eladio Knipping; Naresh Kumar; Ken Darrow; Anne Hampson; Bruce Hedman; James Droppo; Bruce Napier; Cynthia Howard-Reed; Victor Henzel; Steven Nabinger; Andrew Persily; B. deCastro; Lu Wang; Jana Mihalic; Patrick Breysse; Alison Geyh; Timothy Buckley; M. Garci´a; M. Sa´nchez; Isidro rez; Beatriz Torre; Gui Li; Alex Visscher; Chungching Wang; Min-Der Lin; Chenfang Lin; Seoung Kim; Chivalai Temiyasathit; Victoria Chen; Sun-Kyoung Park; Melanie Sattler; Armistead Russell

2008-01-01

329

Antiviral antibodies stimulate production of reactive oxygen species in cultured canine brain cells infected with canine distemper virus.  

PubMed Central

Canine distemper is characterized mainly by respiratory, enteric, and nervous symptoms. Infection of the central nervous system results in demyelination, to which inflammation has been shown to contribute significantly. It has been proposed that macrophages play a major role as effector cells in this process. We report that cultured dog brain cells contain a population of macrophages capable of producing reactive oxygen species as measured by luminol-dependent chemiluminescence. In cultures infected with canine distemper virus, a burst of reactive oxygen is triggered by antiviral antibody. This response depends on the presence of viral antigens on the surfaces of infected cells and is mediated by the interaction of antigen-bound antibody with Fc receptors on the macrophages. Since there is no evidence in vitro or in vivo that oligodendrocytes, the cells forming myelin, are infected, our observation supports the hypothesis that "innocent bystander killing" is important in demyelination caused by canine distemper virus. Reactive oxygen species released from macrophages may contribute to destruction of myelin. Images

Burge, T; Griot, C; Vandevelde, M; Peterhans, E

1989-01-01

330

Exendin-4 Suppresses Src Activation and Reactive Oxygen Species Production in Diabetic Goto-Kakizaki Rat Islets in an Epac-Dependent Manner  

PubMed Central

OBJECTIVE Reactive oxygen species (ROS) is one of most important factors in impaired metabolism secretion coupling in pancreatic ?-cells. We recently reported that elevated ROS production and impaired ATP production at high glucose in diabetic Goto-Kakizaki (GK) rat islets are effectively ameliorated by Src inhibition, suggesting that Src activity is upregulated. In the present study, we investigated whether the glucagon-like peptide-1 signal regulates Src activity and ameliorates endogenous ROS production and ATP production in GK islets using exendin-4. RESEARCH DESIGN AND METHODS Isolated islets from GK and control Wistar rats were used for immunoblotting analyses and measurements of ROS production and ATP content. Src activity was examined by immunoprecipitation of islet lysates followed by immunoblotting. ROS production was measured with a fluorescent probe using dispersed islet cells. RESULTS Exendin-4 significantly decreased phosphorylation of Src Tyr416, which indicates Src activation, in GK islets under 16.7 mmol/l glucose exposure. Glucose-induced ROS production (16.7 mmol/l) in GK islet cells was significantly decreased by coexposure of exendin-4 as well as PP2, a Src inhibitor. The Src kinase–negative mutant expression in GK islets significantly decreased ROS production induced by high glucose. Exendin-4, as well as PP2, significantly increased impaired ATP elevation by high glucose in GK islets. The decrease in ROS production by exendin-4 was not affected by H-89, a PKA inhibitor, and an Epac-specific cAMP analog (8CPT-2Me-cAMP) significantly decreased Src Tyr416 phosphorylation and ROS production. CONCLUSIONS Exendin-4 decreases endogenous ROS production and increases ATP production in diabetic GK rat islets through suppression of Src activation, dependently on Epac.

Mukai, Eri; Fujimoto, Shimpei; Sato, Hiroki; Oneyama, Chitose; Kominato, Rieko; Sato, Yuichi; Sasaki, Mayumi; Nishi, Yuichi; Okada, Masato; Inagaki, Nobuya

2011-01-01

331

The essential oils from Zanthoxylum schinifolium pericarp induce apoptosis of HepG2 human hepatoma cells through increased production of reactive oxygen species.  

PubMed

The volatile extract from dried pericarp of Zanthoxylum schinifolium that was obtained by simultaneous distillation with dichloromethane and water was composed of 29.9% geranyl acetate, 15.8% citronella, 15.4% sabinene and the minor volatile components included beta-myrcene, linalool, (-)-isopulegol, citronellyl acetate, 1,4-dimethyl pyrazole, alpha-terpinene, 3-methyl-6-(1-methylethyl)-2-cyclo-hexene-1-o1 and trans-geraniol. The volatile extract decreased the cell viability and induced apoptotic death in HepG2 human hepatoma cells in a concentration- and time-related manner. In addition, the volatile extract increased the production of reactive oxygen species in a dose-dependent manner. Pretreatment of the cells with Trolox, a well-known antioxidant, significantly suppressed the generation of reactive oxygen species and cell death induced by the extract. However, caspase-3 activity was not changed in the extract-treated cells, suggesting that the extract-induced apoptosis of HepG2 cells is caspase-3 independent. Furthermore, in nude mice inoculated with Huh-7 human hepatoma cells, the extract significantly inhibited tumor development. These results suggest that the volatile extract from Zanthoxylum schinifolium pericarpium is a good candidate for hepatocellular carcinoma (HCC) therapy and that reactive oxygen species are the key signaling molecules in the volatile extract-induced cell death in HepG2 cells. PMID:15863882

Paik, Soon-Young; Koh, Kyung-Hee; Beak, Sung-Mok; Paek, Seung-Hwan; Kim, Jung-Ae

2005-05-01

332

Role of Defective Oct-2 and OCA-B Expression in Immunoglobulin Production and Kaposi's Sarcoma-Associated Herpesvirus Lytic Reactivation in Primary Effusion Lymphoma?  

PubMed Central

Primary effusion lymphoma (PEL) is a distinct type of B-cell non-Hodgkin lymphoma characterized by the presence of Kaposi's sarcoma-associated herpesvirus (KSHV/human herpesvirus 8). Despite having a genotype and gene expression signature of highly differentiated B cells, PEL does not usually express surface or cytoplasmic immunoglobulin (Ig). We show the lack of Oct-2 and OCA-B transcription factors to be responsible, at least in part, for this defect in Ig production. Like Ig genes, ORF50, the key regulator of the switch from latency to lytic reactivation, contains an octamer motif within its promoter. We therefore examined the impact of Oct-2 and OCA-B on ORF50 activation. The binding of Oct-1 to the ORF50 promoter has been shown to significantly enhance ORF50 transactivation. We found that Oct-2, on the other hand, inhibited ORF50 expression and consequently lytic reactivation by competing with Oct-1 for the octamer motif in the ORF50 promoter. Our data suggest that Oct-2 downregulation in infected cells would be favorable to KSHV in allowing for efficient viral reactivation.

Di Bartolo, Daniel L.; Hyjek, Elizabeth; Keller, Shannon; Guasparri, Ilaria; Deng, Hongyu; Sun, Ren; Chadburn, Amy; Knowles, Daniel M.; Cesarman, Ethel

2009-01-01

333

Role of defective Oct-2 and OCA-B expression in immunoglobulin production and Kaposi's sarcoma-associated herpesvirus lytic reactivation in primary effusion lymphoma.  

PubMed

Primary effusion lymphoma (PEL) is a distinct type of B-cell non-Hodgkin lymphoma characterized by the presence of Kaposi's sarcoma-associated herpesvirus (KSHV/human herpesvirus 8). Despite having a genotype and gene expression signature of highly differentiated B cells, PEL does not usually express surface or cytoplasmic immunoglobulin (Ig). We show the lack of Oct-2 and OCA-B transcription factors to be responsible, at least in part, for this defect in Ig production. Like Ig genes, ORF50, the key regulator of the switch from latency to lytic reactivation, contains an octamer motif within its promoter. We therefore examined the impact of Oct-2 and OCA-B on ORF50 activation. The binding of Oct-1 to the ORF50 promoter has been shown to significantly enhance ORF50 transactivation. We found that Oct-2, on the other hand, inhibited ORF50 expression and consequently lytic reactivation by competing with Oct-1 for the octamer motif in the ORF50 promoter. Our data suggest that Oct-2 downregulation in infected cells would be favorable to KSHV in allowing for efficient viral reactivation. PMID:19224997

Di Bartolo, Daniel L; Hyjek, Elizabeth; Keller, Shannon; Guasparri, Ilaria; Deng, Hongyu; Sun, Ren; Chadburn, Amy; Knowles, Daniel M; Cesarman, Ethel

2009-02-18

334

Two-pion production in {alpha}p scattering at 1 GeV/nucleon in the energy region of the Roper resonance excitation  

SciTech Connect

Semiexclusive measurements of the two-pion-production p({alpha},{alpha}{sup '})p{pi}{pi} reaction have been carried out at an energy of E{sub {alpha}}=4.2 GeV at the Saturne-II (Saclay) accelerator with the SPES4-{pi} installation. This reaction was investigated by simultaneous registration of the scattered {alpha} particle and the secondary proton. The obtained results show that the two-pion production in inelastic {alpha}-particle scattering on the proton at the energy of the experiment proceeds mainly through excitation in the target proton of the Roper resonance and its decay with emission of two pions in the isospin I=0,S-wave state.

Alkhazov, G. D.; Kravtsov, A. V.; Mylnikov, V. A.; Orischin, E. M.; Prokofiev, A. N.; Razmyslovich, B. V.; Smirnov, I. B.; Tkach, I. I.; Volkov, S. S.; Zhdanov, A. A. [Petersburg Nuclear Physics Institute, Gatchina RU-188300 (Russian Federation); Augustyniak, W.; Zupranski, P. [Institute for Nuclear Studies, Warsaw PL-00681 (Poland); Boivin, M. [Laboratoire National Saturne, CNRS/IN2P3 and CEA/DSM, Gif-sur-Yvette Cedex F-91191 (France); Boyard, J.-L.; Farhi, L.; Hennino, T.; Jourdain, J.-C.; Kunne, R.; Ramstein, B.; Roy-Stephan, M. [Institut de Physique Nucleaire Orsay, CNRS/IN2P3, Orsay F-91400 (France)] (and others)

2008-08-15

335

Site of mitochondrial reactive oxygen species production in skeletal muscle of chronic obstructive pulmonary disease and its relationship with exercise oxidative stress.  

PubMed

Exercise triggers skeletal muscle oxidative stress in patients with chronic obstructive pulmonary disease (COPD). The objective of this research was to study the specific sites of reactive oxygen species (ROS) production in mitochondria isolated from skeletal muscle of patients with COPD and its relationship with local oxidative stress induced by exercise. Vastus lateralis biopsies were obtained in 16 patients with COPD (66 ± 10 yr; FEV(1), 54 ± 12% ref) and in 14 control subjects with normal lung function who required surgery because of lung cancer (65 ± 7 yr; FEV(1), 91 ± 14% ref) at rest and after exercise. In these biopsies we isolated mitochondria and mitochondrial membrane fragments and determined in vitro mitochondrial oxygen consumption (Mit$$\\stackrel{.}{\\hbox{ V }}$$o(2)) and ROS production before and after inhibition of complex I (rotenone), complex II (stigmatellin), and complex III (antimycin-A). We related the in vitro ROS production during state 3 respiration), which mostly corresponds to the mitochondria respiratory state during exercise, with skeletal muscle oxidative stress after exercise, as measured by thiobarbituric acid reactive substances.State 3 Mit$$\\stackrel{.}{\\hbox{ V }}$$o(2) was similar in patients with COPD and control subjects (191 ± 27 versus 229 ± 46 nmol/min/mg; P = 0.058), whereas H(2)O(2) production was higher in the former (147 ± 39 versus 51 ± 8 pmol/mg/h; P < 0.001). The addition of complexI, II, and III inhibitors identify complex III as the main site of H(2)O(2) release by mitochondria in patients with COPD and in control subjects. The mitochondrial production of H(2)O(2) in state 3 respiration was related (r = 0.69; P < 0.001) to postexercise muscle thiobarbituric acid reactive substance levels. Our results show that complex III is the main site of the enhanced mitochondrial H(2)O(2) production that occurs in skeletal muscle of patients with COPD, and the latter appears to contribute to muscle oxidative damage. PMID:22493009

Puente-Maestu, Luis; Tejedor, Alberto; Lázaro, Alberto; de Miguel, Javier; Alvarez-Sala, Luis; González-Aragoneses, Federico; Simón, Carlos; Agustí, Alvar

2012-04-05

336

Production and characterization of thermoplastic cassava starch, functionalized poly(lactic acid), and their reactive compatibilized blends  

NASA Astrophysics Data System (ADS)

Cassava starch was blended with glycerol using a co-rotating twin-screw extruder (TSE). Thermoplastic cassava starch (TPCS) at a ratio of 70/30 by weight of cassava/glycerol was selected and further blended with other polymers. TPCS sheets made from compression molding had low tensile strength (0.45 +/- 0.05 MPa) and Young's modulus (1.24 +/- 0.58 MPa), but moderate elongation at break (83.0 +/- 0.18.6%), medium level of oxygen permeability, and high water vapor permeability with a very high rate of water absorption. TPCS was blended with poly(lactic acid) (PLA) at various ratios by using a TSE. The blend resins exhibited good properties such as increased thermal stability (Tmax) and crystallinity of PLA, and improved water sensitivity and processability of TPCS. PLA and TPCS exhibited a high interfacial tension between the two phases of 7.9 mJ·m -2, indicating the formation of an incompatible, immiscible blend. SEM micrographs showed a non-homogeneous distribution of TPCS droplets in the PLA continuous phase. TEM micrographs of the blend films made by cast-film extrusion showed coalescence of the TPCS droplets in the PLA continuous phase of the blend, indicating that the compatibility between the polymer pair needs to be improved. A response surface methodology (RSM) design was used to analyze the effects of maleic anhydride (MA) and 2,5-bis(tert-butylperoxy)-2,5-dimethylhexane (Luperox or L101) contents, and TSE screw speed on the degree of grafted MA and number average molecular weight (Mn) of functionalized PLA (PLA-g-MA), a reactive compatibilizer. PLA-g- MA made by reactive extrusion had an array of colors depending on the content of L101 and MA used. New FTIR peaks suggested that MA was grafted onto the PLA backbone and oligomeric MA may occur. Increasing L101 increased the degree of grafting and decreased Mn, but the Mn of the PLA-g-MA's produced with a high amount of L101 was stable during storage. MA exhibited an optimum concentration for maximizing the degree of grafted MA, and increasing MA content retarded the reduction of Mn during processing. However, the Mn of PLA-g-MA during storage decreased more rapidly with a high content of MA. TSE screw speed had an impact on the Mn with the maximum value predicted at 20 rpm. PLA-g-MA compounds differing in Mn and/or grafted MA content were used as reactive polymers with TPCS (to produce binary blends) and as reactive compatibilizers (to produce ternary blends of PLA/TPCS/PLA-g-MA) with TPCS content of 30 wt% using a TSE. As a result of maleation, PLA-g-MA had a higher grafted MA content with a lower Mn, and higher PI. The interaction of anhydride groups from PLA-g-MA and hydroxyl groups from TPCS was found by FTIR. The reactive binary blends exhibited a change in thermal stability, decrease of Tcc, the presence of double melting peaks, and an increase of the Tgs of glycerol and starch. The higher the grafted MA content and/or the higher Mn of the PLA- g-MA used, the better were the distribution and smaller the TPCS domains obtained in the blends. The highest elongation at break was achieved when 30 wt% TPCS was blended with 70 wt% of PLA having 0.1 wt% of grafted MA and Mn of PLA-g-MA with a 45 kDa. Finally, the optimum PLA-g-MA was determined by using the results from PLA-g-MA RSM design and the reactive blending.

Detyothin, Sukeewan

337

Cardiac H11 kinase/Hsp22 stimulates oxidative phosphorylation and modulates mitochondrial reactive oxygen species production: Involvement of a nitric oxide-dependent mechanism.  

PubMed

H11 kinase/Hsp22 (Hsp22), a small heat shock protein upregulated by ischemia/reperfusion, provides cardioprotection equal to ischemic preconditioning (IPC) through a nitric oxide (NO)-dependent mechanism. A main target of NO-mediated preconditioning is the mitochondria, where NO reduces O? consumption and reactive oxygen species (ROS) production during ischemia. Therefore, we tested the hypothesis that Hsp22 overexpression modulates mitochondrial function through an NO-sensitive mechanism. In cardiac mitochondria isolated from transgenic (TG) mice with cardiac-specific overexpression of Hsp22, mitochondrial basal, ADP-dependent, and uncoupled O? consumption was increased in the presence of either glucidic or lipidic substrates. This was associated with a decrease in the maximal capabilities of complexes I and III to generate superoxide anion in combination with an inhibition of superoxide anion production by the reverse electron flow. NO synthase expression and NO production were increased in mitochondria from TG mice. Hsp22-induced increase in O? consumption was abolished either by pretreatment of TG mice with the NO synthase inhibitor L-N(G)-nitroarginine methyl ester (L-NAME) or in isolated mitochondria by the NO scavenger phenyltetramethylimidazoline-1-oxyl-3-oxide. L-NAME pretreatment also restored the reverse electron flow. After anoxia, mitochondria from TG mice showed a reduction in both oxidative phosphorylation and H?O? production, an effect partially reversed by L-NAME. Taken together, these results demonstrate that Hsp22 overexpression increases the capacity of mitochondria to produce NO, which stimulates oxidative phosphorylation in normoxia and decreases oxidative phosphorylation and reactive oxygen species production after anoxia. Such characteristics replicate those conferred by IPC, thereby placing Hsp22 as a potential tool for prophylactic protection of mitochondrial function during ischemia. PMID:22542467

Laure, Lydie; Long, Romain; Lizano, Paulo; Zini, Roland; Berdeaux, Alain; Depre, Christophe; Morin, Didier

2012-04-18

338

The flavonoid dioclein reduces the production of pro-inflammatory mediators in vitro by inhibiting PDE4 activity and scavenging reactive oxygen species.  

PubMed

Reactive oxygen species, cytokines and chemokines produced at inflammatory sites are pivotal events in the progression of many diseases. Flavonoids are well-known for their antioxidant and anti-inflammatory activities. Here, we investigated the effects of the flavonoid dioclein on the production of mediators of inflammation in vitro and possible underlying mechanisms. Murine macrophages were pretreated with dioclein, rolipram, a PDE4 (cyclic nucleotide phosphosdiesterase type 4) inhibitor, or butylated hydroxytoluene (BHT), an antioxidant, and then activated with LPS or LPS/IFN-gamma. The concentration of TNF-alpha, IL-6, CXCL1/KC, CCL2/JE, and nitric oxide (NO) was determined on culture supernatants. To evaluate potential mechanisms of action, dioclein was tested for inhibition of PDE4 activity and for antioxidant properties by chemiluminescence assays. Dioclein was efficient in reducing the production of cytokines, chemokines and NO in a concentration-dependent manner (from 5 to 50muM). Dioclein was more effective than BHT and rolipram, while having similar inhibitory effects to the combination of BHT plus rolipram. Dioclein inhibited PDE4 activity with an approximate IC(50) of 16.8+/-1.4muM and strongly reduced the concentration of reactive oxygen species in cell and cell-free systems, being more effective than the standard antioxidant BHT. The flavonoid dioclein possesses significant antioxidant and PDE4 inhibitory activity, showing that the substance may have substantial advantages over mechanisms of action already described for many flavonoids. Such effects account for the anti-inflammatory effects of dioclein, mainly by reducing the concentration of mediators of inflammation, such as cytokines, chemokines and reactive oxygen species by macrophages. PMID:20152831

Guabiraba, Rodrigo; Campanha-Rodrigues, Ana Lucia; Souza, Adriano L S; Santiago, Helton C; Lugnier, Claire; Alvarez-Leite, Jacqueline; Lemos, Virginia S; Teixeira, Mauro M

2010-02-10

339

Chemical pneumonitis and subsequent reactive airways dysfunction syndrome after a single exposure to a household product: a case report  

Microsoft Academic Search

INTRODUCTION: Household products are usually safe to use. Adverse events arising from their use are mostly reported in patients with pre-existing atopy or pulmonary problems and usually only after a prolonged exposure to such products. We report the case of a patient with no prior problems who developed significant side effects from a single exposure to a domestic product. CASE

Imran Khalid; Amanda M Godfrey; Daniel R Ouellette

2009-01-01

340

Niobium sputtered Havar foils for the high-power production of reactive [18F]fluoride by proton irradiation of [18O]H2O targets.  

PubMed

Niobium sputtered Havar entrance foils were used for the production of reactive [(18)F]fluoride by proton irradiation of [(18)O]H(2)O targets under pressurized conditions. The synthesis yield in the routine production of 2-[(18)F]fluoro-2-deoxy-glucose (FDG) was used as an indicative parameter of the reactivity of (18)F. The yield of FDG obtained with (18)F produced in a target with Havar foil was used as a baseline. No statistically significant difference was found in the saturated yields of (18)F when using Havar or Havar-Nb sputtered entrance foils. However, the amount of long-lived radionuclidic impurities decreased more than 10-fold using the Havar-Nb entrance foil. The average decay corrected synthesis yield of FDG, evaluated over a period of more than 2 years, was found to be approximately 5% higher when using a Havar-Nb entrance foil and a marked improvement on the FDG yield consistency was noted. In addition, the frequency of target rebuilding was greatly diminished when using the Nb sputtered entrance foil. PMID:18242099

Wilson, J S; Avila-Rodriguez, M A; Johnson, R R; Zyuzin, A; McQuarrie, S A

2008-01-31

341

Plastid Genome Instability Leads to Reactive Oxygen Species Production and Plastid-to-Nucleus Retrograde Signaling in Arabidopsis1[C][W][OPEN  

PubMed Central

The plastid genome is highly conserved among plant species, suggesting that alterations of its structure would have dramatic impacts on plant fitness. Nevertheless, little is known about the direct consequences of plastid genome instability. Recently, it was reported that the plastid Whirly proteins WHY1 and WHY3 and a specialized type-I polymerase, POLIB, act as safeguards against plastid genome instability in Arabidopsis (Arabidopsis thaliana). In this study, we use ciprofloxacin, an organelle double-strand break-inducing agent, and the why1why3polIb-1 variegated mutant to evaluate the impact of generalized plastid DNA instability. First, we show that in why1why3polIb-1 and ciprofloxacin-treated plants, plastid genome instability is associated with increased reactive oxygen species production. Then, using different light regimens, we show that the elevated reactive oxygen species production correlates with the appearance of a yellow-variegated phenotype in the why1why3polIb-1 population. This redox imbalance also correlates to modifications of nuclear gene expression patterns, which in turn leads to acclimation to high light. Taken together, these results indicate that plastid genome instability induces an oxidative burst that favors, through nuclear genetic reprogramming, adaptation to subsequent oxidative stresses.

Lepage, Etienne; Zampini, Eric; Brisson, Normand

2013-01-01

342

Embryopathic effects of thalidomide and its hydrolysis products in rabbit embryo culture: evidence for a prostaglandin H synthase (PHS)-dependent, reactive oxygen species (ROS)-mediated mechanism.  

PubMed

Thalidomide (TD) causes birth defects in humans and rabbits via several potential mechanisms, including bioactivation by embryonic prostaglandin H synthase (PHS) enzymes to a reactive intermediate that enhances reactive oxygen species (ROS) formation. We show herein that TD in rabbit embryo culture produces relevant embryopathies, including decreases in head/brain development by 28% and limb bud growth by 71% (P<0.05). Two TD hydrolysis products, 2-phthalimidoglutaramic acid (PGMA) and 2-phthalimidoglutaric acid (PGA), were similarly embryopathic, attenuating otic vesicle (ear) and limb bud formation by up to 36 and 77%, respectively (P<0.05). TD, PGMA, and PGA all increased embryonic DNA oxidation measured as 8-oxoguanine (8-oxoG) by up to 2-fold (P<0.05). Co- or pretreatment with the PHS inhibitors eicosatetraynoic acid (ETYA) or acetylsalicylic acid (ASA), or the free-radical spin trap phenylbutylnitrone (PBN), completely blocked embryonic 8-oxoG formation and/or embryopathies initiated by TD, PGMA, and PGA. This is the first demonstration of limb bud embryopathies initiated by TD, as well as its hydrolysis products, in a mammalian embryo culture model of a species susceptible to TD in vivo, indicating that all likely contribute to TD teratogenicity in vivo, in part through PHS-dependent, ROS-mediated mechanisms. PMID:21502285

Lee, Crystal J J; Gonçalves, Luisa L; Wells, Peter G

2011-04-18

343

TCDD decreases ATP levels and increases reactive oxygen production through changes in mitochondrial F F{sub 1}-ATP synthase and ubiquinone  

SciTech Connect

Mitochondria generate ATP and participate in signal transduction and cellular pathology and/or cell death. TCDD (2,3,7,8-tetrachlorodibenzo-p-dioxin) decreases hepatic ATP levels and generates mitochondrial oxidative DNA damage, which is exacerbated by increasing mitochondrial glutathione redox state and by inner membrane hyperpolarization. This study identifies mitochondrial targets of TCDD that initiate and sustain reactive oxygen production and decreased ATP levels. One week after treating mice with TCDD, liver ubiquinone (Q) levels were significantly decreased, while rates of succinoxidase and Q-cytochrome c oxidoreductase activities were increased. However, the expected increase in Q reduction state following TCDD treatment did not occur; instead, Q was more oxidized. These results could be explained by an ATP synthase defect, a premise supported by the unusual finding that TCDD lowers ATP/O ratios without concomitant changes in respiratory control ratios. Such results suggest either a futile cycle in ATP synthesis, or hydrolysis of newly synthesized ATP prior to release. The TCDD-mediated decrease in Q, concomitant with an increase in respiration, increases complex 3 redox cycling. This acts in concert with glutathione to increase membrane potential and reactive oxygen production. The proposed defect in ATP synthase explains both the greater respiratory rates and the lower tissue ATP levels.

Shertzer, Howard G. [Department of Environmental Health and Center for Environmental Genetics, University of Cincinnati Medical Center, P.O. Box 670056 Cincinnati, OH 45267-0056 (United States)]. E-mail: shertzhg@ucmail.uc.edu; Genter, Mary Beth [Department of Environmental Health and Center for Environmental Genetics, University of Cincinnati Medical Center, P.O. Box 670056 Cincinnati, OH 45267-0056 (United States); Shen, Dongxiao [Department of Environmental Health and Center for Environmental Genetics, University of Cincinnati Medical Center, P.O. Box 670056 Cincinnati, OH 45267-0056 (United States); Nebert, Daniel W. [Department of Environmental Health and Center for Environmental Genetics, University of Cincinnati Medical Center, P.O. Box 670056 Cincinnati, OH 45267-0056 (United States); Chen, Ying [Department of Environmental Health and Center for Environmental Genetics, University of Cincinnati Medical Center, P.O. Box 670056 Cincinnati, OH 45267-0056 (United States); Dalton, Timothy P. [Department of Environmental Health and Center for Environmental Genetics, University of Cincinnati Medical Center, P.O. Box 670056 Cincinnati, OH 45267-0056 (United States)

2006-12-15

344

Reactivity of H2O2 towards different UO2-based materials: The relative impact of radiolysis products revisited  

NASA Astrophysics Data System (ADS)

The reactivity of doped UO2 such as SIMFUEL towards H2O2 has been shown to be fairly similar to that of pure UO2. However, the oxidative dissolution yield, i.e. the ratio between the amount of dissolved uranium and the amount of consumed H2O2 is significantly lower for doped UO2. In this work we have studied the mechanistic difference between SIMFUEL and pure UO2. H2O2 can be catalytically decomposed on UO2 in competition with the redox process in which U(IV) is oxidized. The latter process leads to the dissolution of oxidized uranium. The first step in the catalytic decomposition is the formation of hydroxyl radicals. The presence of hydroxyl radicals was verified using Tris buffer as a radical scavenger. For both UO2 and SIMFUEL pellets, significant amounts of hydroxyl radicals were formed. The results also show that the difference in dissolution yield between the two materials can mainly be attributed to differences in the redox reactivity. Based on this, the rate constants for electron transfer were revised and the relative impact of the radiolytic oxidants in oxidative dissolution of UO2 and SIMFUEL pellets were calculated. The impact of H2O2 is shown to be slightly reduced.

Lousada, Cláudio M.; Trummer, Martin; Jonsson, Mats

2013-03-01

345

Angiotensin Type 1a Receptor Signaling Is Not Necessary for the Production of Reactive Oxygen Species in Polymorphonuclear Leukocytes  

PubMed Central

Background. Although angiotensin II (Ang II) has inflammatory effects, little is known about its role in polymorphonuclear leucocytes (PMLs). To elucidate the role of Ang II in PMLs ROS production, we examined hydrogen peroxide (H2O2), one of the ROS, and NO production in AT1a receptor knockout (AT1KO) mice. Methods and Results. PMLs were analyzed from Ang II type 1a receptor knockout mice (AT1KO) and C57BL/6 wild type mice. Using flow cytometry, we studied hydrogen peroxide (H2O2) production from PMLs after Staphylococcus aureus phagocytosis or phorbol myristate acetate (PMA) stimulation. Nitric oxide (NO) production in the AT1KO was low at basal and after phagocytosis. In the AT1KO, basal H2O2 production was low. After PMA or phagocytosis stimulation, however, H2O2 production was comparable to wild type mice. Next we studied the H2O2 production in C57BL/6 mice exposed to Ang II or saline. H2O2 production stimulated by PMA or phagocytosis did not differ between the two groups. Conclusions. AT1a pathway is not necessary for PMLs H2O2 production but for NO production. There was a compensatory pathway for H2O2 production other than the AT1a receptor.

Yamato, Fumiko; Tsuji, Shoji; Hasui, Masafumi; Kaneko, Kazunari

2012-01-01

346

Observation of vertical motion above a subduction zone using Persistent Scatterer Interferometry Wide Area Product, SW Crete  

NASA Astrophysics Data System (ADS)

Persistent scatterer interferometry (PSI) is a powerful tool to quantify vertical motion of the Earth's surface with millimeter accuracy at a wide spatial coverage of hundreds of square km. Persistent Scatterers (PS) are phase stable point targets with a consistent and strong reflectivity observed over a long time (Ferretti et al., 2001, IEEE Transactions on Geoscience and Remote Sensing). These PS originate from man-made features, or natural features like rocks. This technique, which was originally developed for urban areas (Ferretti et al., 2001, IEEE Transactions on Geoscience and Remote Sensing), is now enhanced and applied for the detection of PS in rural areas by the operational PSI system Wide Area Product (PSI-GENESIS) of the German Aerospace Center (DLR). The detection is possible over large areas (100 km by 100 km). A problem with the wide-area approach is to cope with inhomogeneous PS densities within an area and variable topography. Difficulties arise from uncompensated atmospheric effects and spatial error propagation. The number of available scenes per stack is limited but the amount of data to be processed is large (about 1 Gigabyte per stack). We tested the PSI technique for the island of Crete. Therefore, we used data of the ERS-1 and ERS-2 satellites of the European Space Agency (ESA) for the PSI analysis. The western part of the island is covered by 39 Synthetic Aperture Radar (SAR) images acquired between 1992 and 2000 of the ERS Track 193. We chose the island of Crete as test site due to its close location to the Hellenic subduction zone, which allows the observation of vertical surface motion. Crete is bounded by seismogenic faults that produced large and destructive earthquakes in the past, such as the MS > 8 earthquake in 365 AD. Vertical surface motion in the vicinity of a subduction zone may imply locking of the plate interface. Our preliminary findings of the W part of the island show an inhomogeneous distribution of PS over the whole scene. The northern part of Crete is more flat than the southern part, which leads to a more homogenous PS distribution in the North. The southern part consists of high mountain ranges, therefore the detection of PS is only possible outside the radar shadows. The northern part shows no significant vertical motion pattern. The southern coast shows uplift in the range of 3 mm/yr. The SW corner of the island shows a strong uplift of up to 5 mm/yr. Further analysis is still in progress and additional atmospheric corrections are necessary to validate our results. We interpret the observed vertical motion in Crete as interseismic strain accumulation. This implies that the subduction zone interface is at least partly locked and hence, may produce another large earthquake in the future.

Rieger, S. M.; Adam, N.; Friedrich, A. M.

2011-12-01

347

Phospholipase D?1 and Phosphatidic Acid Regulate NADPH Oxidase Activity and Production of Reactive Oxygen Species in ABA-Mediated Stomatal Closure in Arabidopsis[C][W][OA  

PubMed Central

We determined the role of Phospholipase D?1 (PLD?1) and its lipid product phosphatidic acid (PA) in abscisic acid (ABA)-induced production of reactive oxygen species (ROS) in Arabidopsis thaliana guard cells. The pld?1 mutant failed to produce ROS in guard cells in response to ABA. ABA stimulated NADPH oxidase activity in wild-type guard cells but not in pld?1 cells, whereas PA stimulated NADPH oxidase activity in both genotypes. PA bound to recombinant Arabidopsis NADPH oxidase RbohD (respiratory burst oxidase homolog D) and RbohF. The PA binding motifs were identified, and mutation of the Arg residues 149, 150, 156, and 157 in RbohD resulted in the loss of PA binding and the loss of PA activation of RbohD. The rbohD mutant expressing non-PA-binding RbohD was compromised in ABA-mediated ROS production and stomatal closure. Furthermore, ABA-induced production of nitric oxide (NO) was impaired in pld?1 guard cells. Disruption of PA binding to ABI1 protein phosphatase 2C did not affect ABA-induced production of ROS or NO, but the PA–ABI1 interaction was required for stomatal closure induced by ABA, H2O2, or NO. Thus, PA is as a central lipid signaling molecule that links different components in the ABA signaling network in guard cells.

Zhang, Yanyan; Zhu, Huiying; Zhang, Qun; Li, Maoyin; Yan, Min; Wang, Rong; Wang, Liling; Welti, Ruth; Zhang, Wenhua; Wang, Xuemin

2009-01-01

348

Mountain cedar pollen induces IgE-independent mast cell degranulation, IL-4 production, and intracellular reactive oxygen species generation  

PubMed Central

Cedar pollens cause severe allergic disease throughout the world. We have previously characterized allergenic pollen glycoproteins from mountain cedar (Juniperus ashei) that bind to allergen-specific immunoglobulin E (IgE). In the present report, we investigated an alternative pathway of mast cell activation by mountain cedar pollen extract through IgE-independent mechanisms. We show that mountain cedar pollen directly induces mast cell serotonin and IL-4 release and enhances release induced by IgE cross-linking. Concomitant with mediator release, high levels of intracellular reactive oxygen species (ROS) were generated, and both ROS and serotonin release were inhibited by anti-oxidants. These findings suggest that alternative mechanisms exist whereby pollen exposure enhances allergic inflammatory mediator release through mechanisms that involve ROS. These mechanisms have the potential for enhancing the allergenic potency of pollens.

Endo, Shuichiro; Hochman, Daniel J.; Midoro-Horiuti, Terumi; Goldblum, Randall M.; Brooks, Edward G.

2011-01-01

349

Photosensitization of CdSe/ZnS QDs and reliability of assays for reactive oxygen species production.  

SciTech Connect

CdSe/ZnS quantum dots (QDs) conjugated to biomolecules that can act as electron donors are said to be 'photosensitized': that is, they are able to oxidize or reduce molecules whose redox potential lies inside their band edges, in particular molecular oxygen and water. This leads to the formation of reactive oxygen species (ROS) and phototoxicity. In this work, we quantify the generation of different forms of ROS from as-synthesized QDs in toluene; water-solubilized, unconjugated QDs; QDs conjugated to the neurotransmitter dopamine; and dopamine alone. Results of indirect fluorescent ROS assays, both in solution and inside cells, are compared with those of spin-trap electron paramagentic resonance spectroscopy (EPR). The effect of these particles on the metabolism of mammalian cells is shown to be dependent upon light exposure and proportional to the amount of ROS generated.

Cooper, D. R.; Dimitrijevic, N. M.; Nadeau, J. L.; McGill Univ.

2010-01-01

350

Photosensitization of CdSe/ZnS QDs and reliability of assays for reactive oxygen species production  

NASA Astrophysics Data System (ADS)

CdSe/ZnS quantum dots (QDs) conjugated to biomolecules that can act as electron donors are said to be ``photosensitized'': that is, they are able to oxidize or reduce molecules whose redox potential lies inside their band edges, in particular molecular oxygen and water. This leads to the formation of reactive oxygen species (ROS) and phototoxicity. In this work, we quantify the generation of different forms of ROS from as-synthesized QDs in toluene; water-solubilized, unconjugated QDs; QDs conjugated to the neurotransmitter dopamine; and dopamine alone. Results of indirect fluorescent ROS assays, both in solution and inside cells, are compared with those of spin-trap electron paramagnetic resonance spectroscopy (EPR). The effect of these particles on the metabolism of mammalian cells is shown to be dependent upon light exposure and proportional to the amount of ROS generated.

Cooper, Daniel R.; Dimitrijevic, Nada M.; Nadeau, Jay L.

2010-01-01

351

Optimization of furfural production from D-xylose with formic acid as catalyst in a reactive extraction system.  

PubMed

Furfural is one of the most promising platform chemicals derived from biomass. In this study, response surface methodology (RSM) was utilized to determine four important parameters including reaction temperature (170-210°C), formic acid concentration (5-25 g/L), o-nitrotoluene volume percentage (20-80 vt.%), and residence time (40-200 min). The maximum furfural yield of 74% and selectivity of 86% were achieved at 190°C for 20 g/L formic acid concentration and 75 vt.% o-nitrotoluene by 75 min. The high boiling solvent, o-nitrotoluene, was recommended as extraction solvent in a reactive extraction system to obtain high furfural yield and reduce furfural-solvent separation costs. Although the addition of halides to the xylose solutions enhanced the furfural yield and selectivity, the concentration of halides was not an important factor on the furfural yield and selectivity. PMID:23434814

Yang, Wandian; Li, Pingli; Bo, Dechen; Chang, Heying; Wang, Xiaowei; Zhu, Tao

2013-02-04

352

Artesunate Activates Mitochondrial Apoptosis in Breast Cancer Cells via Iron-catalyzed Lysosomal Reactive Oxygen Species Production*  

PubMed Central

The antimalarial agent artesunate (ART) activates programmed cell death (PCD) in cancer cells in a manner dependent on the presence of iron and the generation of reactive oxygen species. In malaria parasites, ART cytotoxicity originates from interactions with heme-derived iron within the food vacuole. The analogous digestive compartment of mammalian cells, the lysosome, similarly contains high levels of redox-active iron and in response to specific stimuli can initiate mitochondrial apoptosis. We thus investigated the role of lysosomes in ART-induced PCD and determined that in MCF-7 breast cancer cells ART activates lysosome-dependent mitochondrial outer membrane permeabilization. ART impacted endolysosomal and autophagosomal compartments, inhibiting autophagosome turnover and causing perinuclear clustering of autophagosomes, early and late endosomes, and lysosomes. Lysosomal iron chelation blocked all measured parameters of ART-induced PCD, whereas lysosomal iron loading enhanced death, thus identifying lysosomal iron as the lethal source of reactive oxygen species upstream of mitochondrial outer membrane permeabilization. Moreover, lysosomal inhibitors chloroquine and bafilomycin A1 reduced ART-activated PCD, evidencing a requirement for lysosomal function during PCD signaling. ART killing did not involve activation of the BH3-only protein, Bid, yet ART enhanced TNF-mediated Bid cleavage. We additionally demonstrated the lysosomal PCD pathway in T47D and MDA-MB-231 breast cancer cells. Importantly, non-tumorigenic MCF-10A cells resisted ART-induced PCD. Together, our data suggest that ART triggers PCD via engagement of distinct, interconnected PCD pathways, with hierarchical signaling from lysosomes to mitochondria, suggesting a potential clinical use of ART for targeting lysosomes in cancer treatment.

Hamacher-Brady, Anne; Stein, Henning A.; Turschner, Simon; Toegel, Ina; Mora, Rodrigo; Jennewein, Nina; Efferth, Thomas; Eils, Roland; Brady, Nathan R.

2011-01-01

353

Identification and determination of individual sophorolipids in fermentation products by gradient elution high-performance liquid chromatography with evaporative light-scattering detection.  

PubMed

High-performance liquid chromatography (HPLC) was used for the characterization of sophorolipids, one of the most important types of glycolipid biosurfactants. By using gradient elution with a water-acetonitrile mixture on a reversed-phase (C18) column and evaporative light-scattering detection, resolution of all the important individual sophorolipids present in fermentation products was achieved. In addition to HPLC, a combination of techniques involving selective production by fermentation of sophorolipids, chemical conversions of the products, separation methods and, for identification of lipidic chains of sophorolipids, gas chromatography and mass spectrometry was used. This led to the identification of almost all significant compounds observed in HPLC, including several previously unreported sophorolipids. As a result, a rapid method is now available for investigations of the influence of fermentation conditions on the nature and quantitative distribution of the sophorolipid products obtained. PMID:8245170

Davila, A M; Marchal, R; Monin, N; Vandecasteele, J P

1993-10-01

354

Reactive angioendotheliomatosis.  

PubMed

Angioendotheliomatosis is a rare disorder with both cutaneous and systemic clinical presentations. We agree that there is evidence in the existing medical literature for the separation of reactive and malignant (neoplastic) variants of angioendotheliomatosis. These variants share similar histologic and ultrastructural features but seem clinically distinct. The reactive variant has been associated (four of seven cases, including our patient) with existing or preexisting subacute bacterial endocarditis. PMID:6444957

Martin, S; Pitcher, D; Tschen, J; Wolf, J E

1980-02-01

355

Seasonality of energetic functioning and production of reactive oxygen species by lugworm (Arenicola marina) mitochondria exposed to acute temperature changes  

Microsoft Academic Search

The influence of seasonal and acute temperature changes on mitochondrial functions were studied in isolated mitochondria of the eurythermal lugworm Arenicola marina (Polychaeta), with special emphasis on the interdependence of membrane potential and radical production. Acclimatisation of lugworms to pre- spawning\\/summer conditions is associated with rising mitochondrial substrate oxidation rates, higher proton leakage rates, elevated membrane potentials, and increased production

Martina Keller; Angela Maria Sommer; Hans O. Pörtner; Doris Abele; Alfred Wegener

2004-01-01

356

Measurement of D ?± meson production and determination of F2^{cbar{c}} at low Q 2 in deep-inelastic scattering at HERA  

NASA Astrophysics Data System (ADS)

Inclusive production of D ? mesons in deep-inelastic ep scattering at HERA is studied in the range 5< Q 2<100 GeV2 of the photon virtuality and 0.02< y<0.7 of the inelasticity of the scattering process. The observed phase space for the D ? meson is p T ( D ?)>1.25 GeV and | ?( D ?)|<1.8. The data sample corresponds to an integrated luminosity of 348 pb-1 collected with the H1 detector. Single and double differential cross sections are measured and the charm contribution {F2^{cbar{c}}} to the proton structure function F 2 is determined. The results are compared to perturbative QCD predictions at next-to-leading order implementing different schemes for the charm mass treatment and with Monte Carlo models based on leading order matrix elements with parton showers.

Aaron, F. D.; Alexa, C.; Andreev, V.; Backovic, S.; Baghdasaryan, A.; Baghdasaryan, S.; Barrelet, E.; Bartel, W.; Begzsuren, K.; Belousov, A.; Belov, P.; Bizot, J. C.; Boenig, M.-O.; Boudry, V.; Bozovic-Jelisavcic, I.; Bracinik, J.; Brandt, G.; Brinkmann, M.; Brisson, V.; Britzger, D.; Bruncko, D.; Bunyatyan, A.; Buschhorn, G.; Bystritskaya, L.; Campbell, A. J.; Cantun Avila, K. B.; Ceccopieri, F.; Cerny, K.; Cerny, V.; Chekelian, V.; Contreras, J. G.; Coughlan, J. A.; Cvach, J.; Dainton, J. B.; Daum, K.; Delcourt, B.; Delvax, J.; De Wolf, E. A.; Diaconu, C.; Dobre, M.; Dodonov, V.; Dossanov, A.; Dubak, A.; Eckerlin, G.; Egli, S.; Eliseev, A.; Elsen, E.; Favart, L.; Fedotov, A.; Felst, R.; Feltesse, J.; Ferencei, J.; Fischer, D.-J.; Fleischer, M.; Fomenko, A.; Gabathuler, E.; Gayler, J.; Ghazaryan, S.; Glazov, A.; Goerlich, L.; Gogitidze, N.; Gouzevitch, M.; Grab, C.; Grebenyuk, A.; Greenshaw, T.; Grell, B. R.; Grindhammer, G.; Habib, S.; Haidt, D.; Helebrant, C.; Henderson, R. C. W.; Hennekemper, E.; Henschel, H.; Herbst, M.; Herrera, G.; Hildebrandt, M.; Hiller, K. H.; Hoffmann, D.; Horisberger, R.; Hreus, T.; Huber, F.; Jacquet, M.; Janssen, X.; Jönsson, L.; Jung, A. W.; Jung, H.; Kapichine, M.; Kenyon, I. R.; Kiesling, C.; Klein, M.; Kleinwort, C.; Kluge, T.; Kogler, R.; Kostka, P.; Kraemer, M.; Kretzschmar, J.; Krüger, K.; Landon, M. P. J.; Lange, W.; Laštovi?ka-Medin, G.; Laycock, P.; Lebedev, A.; Lendermann, V.; Levonian, S.; Lipka, K.; List, B.; List, J.; Lopez-Fernandez, R.; Lubimov, V.; Makankine, A.; Malinovski, E.; Marage, P.; Martyn, H.-U.; Maxfield, S. J.; Mehta, A.; Meyer, A. B.; Meyer, H.; Meyer, J.; Mikocki, S.; Milcewicz-Mika, I.; Moreau, F.; Morozov, A.; Morris, J. V.; Mudrinic, M.; Müller, K.; Naumann, Th.; Newman, P. R.; Niebuhr, C.; Nikitin, D.; Nowak, G.; Nowak, K.; Olsson, J. E.; Ozerov, D.; Pahl, P.; Palichik, V.; Panagoulias, I.; Pandurovic, M.; Papadopoulou, Th.; Pascaud, C.; Patel, G. D.; Perez, E.; Petrukhin, A.; Picuric, I.; Piec, S.; Pirumov, H.; Pitzl, D.; Pla?akyt?, R.; Pokorny, B.; Polifka, R.; Povh, B.; Radescu, V.; Raicevic, N.; Ravdandorj, T.; Reimer, P.; Rizvi, E.; Robmann, P.; Roosen, R.; Rostovtsev, A.; Rotaru, M.; Ruiz Tabasco, J. E.; Rusakov, S.; Šálek, D.; Sankey, D. P. C.; Sauter, M.; Sauvan, E.; Schmitt, S.; Schoeffel, L.; Schöning, A.; Schultz-Coulon, H.-C.; Sefkow, F.; Shtarkov, L. N.; Shushkevich, S.; Sloan, T.; Smiljanic, I.; Soloviev, Y.; Sopicki, P.; South, D.; Spaskov, V.; Specka, A.; Staykova, Z.; Steder, M.; Stella, B.; Stoicea, G.; Straumann, U.; Sykora, T.; Thompson, P. D.; Toll, T.; Tran, T. H.; Traynor, D.; Truöl, P.; Tsakov, I.; Tseepeldorj, B.; Turnau, J.; Urban, K.; Valkárová, A.; Vallée, C.; Van Mechelen, P.; Vazdik, Y.; Wegener, D.; Wünsch, E.; Žá?ek, J.; Zálešák, J.; Zhang, Z.; Zhokin, A.; Zohrabyan, H.; Zomer, F.

2011-10-01

357

Optimal reactive power allocation using PSO-DV hybrid algorithm  

Microsoft Academic Search

The reactive power allocation aspect has received considerable attention in present day power system operation and control. At heavy\\/light load periods, voltage control is provided by the controllable reactive sources, which are scattered throughout the transmission network, function in co-ordination. Reactive power dispatch problem can be formulated as a nonlinear constrained optimization problem. This paper presents a Particle Swarm with

K. Vaisakh; P. Kanta Rao

2008-01-01

358

Inhibitors of succinate: quinone reductase/Complex II regulate production of mitochondrial reactive oxygen species and protect normal cells from ischemic damage but induce specific cancer cell death.  

PubMed

Succinate:quinone reductase (SQR) of Complex II occupies a unique central point in the mitochondrial respiratory system as a major source of electrons driving reactive oxygen species (ROS) production. It is an ideal pharmaceutical target for modulating ROS levels in normal cells to prevent oxidative stress-induced damage or alternatively,increase ROS in cancer cells, inducing cell death.The value of drugs like diazoxide to prevent ROS production,protecting normal cells, whereas vitamin E analogues promote ROS in cancer cells to kill them is highlighted. As pharmaceuticals these agents may prevent degenerative disease and their modes of action are presently being fully explored. The evidence that SDH/Complex II is tightly coupled to the NADH/NAD+ ratio in all cells,impacted by the available supplies of Krebs cycle intermediates as essential NAD-linked substrates, and the NAD+-dependent regulation of SDH/Complex II are reviewed, as are links to the NAD+-dependent dehydrogenases, Complex I and the E3 dihiydrolipoamide dehydrogenase to produce ROS. This review collates and discusses diverse sources of information relating to ROS production in different biological systems, focussing on evidence for SQR as the main source of ROS production in mitochondria, particularly its relevance to protection from oxidative stress and to the mitochondrial-targeted anti cancer drugs (mitocans) as novel cancer therapies [corrected]. PMID:21863476

Ralph, Stephen J; Moreno-Sánchez, Rafael; Neuzil, Jiri; Rodríguez-Enríquez, Sara

2011-08-24

359

Understanding composite explosive energetics: 4. Reactive flow modeling of aluminum reaction kinetics in PETN and TNT using normalized product equation of state  

SciTech Connect

Using Fabry-Perot interferometry techniques, we have determined the early time rate of energy release from detonating PETN and TNT explosives filled with 5 to 20 wt % of either 5 {mu}m or 18 {mu}m spherical aluminum with the detonation products, and calculate the extent of reaction at 1--3 {mu}s after the detonation. All of the metal in PETN formulations filled with 5 wt % and 10 wt % of either 5 {mu}m or 18 {mu}m aluminum reacted within 1.5 {mu}s, resulting in an increase of 18--22% in energy compared to pure PETN. For TNT formulations, between 5 to 10 wt % aluminum reacts completely with the same timeframe. A reactive flow hydrodynamic code model based on the Zeldovich-von Neumann-Doring (ZND) description of the reaction zone and subsequent reaction product expansion (Taylor wave) is used to address the reaction rate of the aluminum particles with detonation product gases. The detonation product JWL equation of state is derived from that of pure PETN using a parametric normalization methodology.

Tao, W.C.; Tarver, C.M.; Kury, J.W.; Lee, C.G.; Ornellas, D.L.

1993-07-01

360

TRPC3-mediated Ca2+ influx contributes to Rac1-mediated production of reactive oxygen species in MLP-deficient mouse hearts.  

PubMed

Dilated cardiomyopathy (DCM) is a myocardial disorder that is characterized by dilation and dysfunction of the left ventricle (LV). Accumulating evidence has implicated aberrant Ca(2+) signaling and oxidative stress in the progression of DCM, but the molecular details are unknown. In the present study, we report that inhibition of the transient receptor potential canonical 3 (TRPC3) channels partially prevents LV dilation and dysfunction in muscle LIM protein-deficient (MLP (-/-)) mice, a murine model of DCM. The expression level of TRPC3 and the activity of Ca(2+)/calmodulin-dependent kinase II (CaMKII) were increased in MLP (-/-) mouse hearts. Acitivity of Rac1, a small GTP-binding protein that participates in NADPH oxidase (Nox) activation, and the production of reactive oxygen species (ROS) were also increased in MLP (-/-) mouse hearts. Treatment with pyrazole-3, a TRPC3 selective inhibitor, strongly suppressed the increased activities of CaMKII and Rac1, as well as ROS production. In contrast, activation of TRPC3 by 1-oleoyl-2-acetyl-sn-glycerol (OAG), or by mechanical stretch, induced ROS production in rat neonatal cardiomyocytes. These results suggest that up-regulation of TRPC3 is responsible for the increase in CaMKII activity and the Nox-mediated ROS production in MLP (-/-) mouse cardiomyocytes, and that inhibition of TRPC3 is an effective therapeutic strategy to prevent the progression of DCM. PMID:21565173

Kitajima, Naoyuki; Watanabe, Kunihiro; Morimoto, Sachio; Sato, Yoji; Kiyonaka, Shigeki; Hoshijima, Masahiko; Ikeda, Yasuhiro; Nakaya, Michio; Ide, Tomomi; Mori, Yasuo; Kurose, Hitoshi; Nishida, Motohiro

2011-05-03

361

Pyruvate: immunonutritional effects on neutrophil intracellular amino or alpha-keto acid profiles and reactive oxygen species production.  

PubMed

For the first time the immunonutritional role of pyruvate on neutrophils (PMN), free ?-keto and amino acid profiles, important reactive oxygen species (ROS) produced [superoxide anion (O(2) (-)), hydrogen peroxide (H(2)O(2))] as well as released myeloperoxidase (MPO) acitivity has been investigated. Exogenous pyruvate significantly increased PMN pyruvate, ?-ketoglutarate, asparagine, glutamine, aspartate, glutamate, arginine, citrulline, alanine, glycine and serine in a dose as well as duration of exposure dependent manner. Moreover, increases in O(2) (-) formation, H(2)O(2)-generation and MPO acitivity in parallel with intracellular pyruvate changes have also been detected. Regarding the interesting findings presented here we believe, that pyruvate fulfils considerably the criteria for a potent immunonutritional molecule in the regulation of the PMN dynamic ?-keto and amino acid pools. Moreover it also plays an important role in parallel modulation of the granulocyte-dependent innate immune regulation. Although further research is necessary to clarify pyruvate's sole therapeutical role in critically ill patients' immunonutrition, the first scientific successes seem to be very promising. PMID:20839016

Mathioudakis, D; Engel, J; Welters, I D; Dehne, M G; Matejec, R; Harbach, H; Henrich, M; Schwandner, T; Fuchs, M; Weismüller, K; Scheffer, G J; Mühling, Jörg

2010-09-14

362

Induction of apoptosis via the modulation of reactive oxygen species (ROS) production in the treatment of myeloid leukemia.  

PubMed

Recent advances in genetic and molecular biology have provided greater insight into the biology of acute myeloid leukemia (AML). These investigations have shown that AML is a heterogeneous disease of biologically different entities. Current therapeutic approaches to AML are based on chemotherapy, but the side effects of the drugs used and various complications, including infections and bleeding, are sometimes fatal. In addition, responses to therapy and long-term outcome differ depending on the subentity in question. Therefore, it is essential to develop new therapeutic strategies such as biology adapted treatment based on the individual molecular pathogenesis of AML. Natural compounds appear to be safer than the current chemotherapeutic drugs, and we have therefore sought new potential agents among various natural compounds with the ability to induce the apoptosis of myeloid leukemic cells. Recently, we found that a highly toxic reactive oxygen species (ROS) generated via the hydrogen peroxide/myeloperoxidase [H(2)O(2)/MPO/halide] system by natural compounds induces apoptosis in MPO-positive leukemic cells. This result is of great interest in establishing novel therapeutic approaches to AML mediated through ROS-induced apoptosis of leukemic cells. PMID:17076648

Kizaki, Masahiro; Xian, Mingji; Sagawa, Morihiko; Ikeda, Yasuo

2006-10-01

363

Transient Influx of nickel in root mitochondria modulates organic acid and reactive oxygen species production in nickel hyperaccumulator Alyssum murale.  

PubMed

Mitochondria are important targets of metal toxicity and are also vital for maintaining metal homeostasis. Here, we examined the potential role of mitochondria in homeostasis of nickel in the roots of nickel hyperaccumulator plant Alyssum murale. We evaluated the biochemical basis of nickel tolerance by comparing the role of mitochondria in closely related nickel hyperaccumulator A. murale and non-accumulator Alyssum montanum. Evidence is presented for the rapid and transient influx of nickel in root mitochondria of nickel hyperaccumulator A. murale. In an early response to nickel treatment, substantial nickel influx was observed in mitochondria prior to sequestration in vacuoles in the roots of hyperaccumulator A. murale compared with non-accumulator A. montanum. In addition, the mitochondrial Krebs cycle was modulated to increase synthesis of malic acid and citric acid involvement in nickel hyperaccumulation. Furthermore, malic acid, which is reported to form a complex with nickel in hyperaccumulators, was also found to reduce the reactive oxygen species generation induced by nickel. We propose that the interaction of nickel with mitochondria is imperative in the early steps of nickel uptake in nickel hyperaccumulator plants. Initial uptake of nickel in roots results in biochemical responses in the root mitochondria indicating its vital role in homeostasis of nickel ions in hyperaccumulation. PMID:23322782

Agrawal, Bhavana; Czymmek, Kirk J; Sparks, Donald L; Bais, Harsh P

2013-01-15