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1

Reactive scattering at low energy  

NASA Astrophysics Data System (ADS)

We present results for atom--diatom reactive scattering calculations performed within the hyperspherical coordinate framework, using the ABC program developed by Manolopoulos and coworkers^[(D. Skouteris, J. F. Castillo, and D. E. Manolopoulos, Comput. Phys. Commun. 133), 128 (2000).^]. Cross sections are reported for the D+H_2arrowH+DH reaction at very low energies, for different initial vibrational states of H_2. Although the cross sections increase dramatically as we go from v=0 to v=1 and v=2, they then level off, as the reaction barrier seems to rise and keep up with the energy of the higher vibrational levels.

Simbotin, I.; Côté, R.; Balakrishnan, N.; Dalgarno, A.

2001-05-01

2

Production of a Biomimetic Fe(I)-S Phase on Pyrite by Atomic-Hydrogen Beam-Surface Reactive Scattering  

PubMed Central

Molecular beam-surface scattering and X-ray absorption spectroscopic experiments were employed to study the reaction of deuterium atoms with a pyrite, FeS2 (100), surface and to investigate the electronic and geometric structures of the resulting Fe-S phases. Incident D atoms, produced by a radio frequency 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, D2S 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 D2S 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)-S2 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.

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

2011-01-01

3

Quantum hydrodynamics: capturing a reactive scattering resonance.  

PubMed

The hydrodynamic equations of motion associated with the de Broglie-Bohm formulation of quantum mechanics are solved using a meshless method based upon a moving least-squares approach. An arbitrary Lagrangian-Eulerian frame of reference and a regridding algorithm which adds and deletes computational points are used to maintain a uniform and nearly constant interparticle spacing. The methodology also uses averaged fields to maintain unitary time evolution. The numerical instabilities associated with the formation of nodes in the reflected portion of the wave packet are avoided by adding artificial viscosity to the equations of motion. A new and more robust artificial viscosity algorithm is presented which gives accurate scattering results and is capable of capturing quantum resonances. The methodology is applied to a one-dimensional model chemical reaction that is known to exhibit a quantum resonance. The correlation function approach is used to compute the reactive scattering matrix, reaction probability, and time delay as a function of energy. Excellent agreement is obtained between the scattering results based upon the quantum hydrodynamic approach and those based upon standard quantum mechanics. This is the first clear demonstration of the ability of moving grid approaches to accurately and robustly reproduce resonance structures in a scattering system. PMID:16108631

Derrickson, Sean W; Bittner, Eric R; Kendrick, Brian K

2005-08-01

4

Plane wave packet formulation of atom-plus-diatom quantum reactive scattering  

NASA Astrophysics Data System (ADS)

We recently interpreted several reactive scattering experiments using a plane wave packet (PWP) formulation of quantum scattering theory [see, e.g., S. C. Althorpe, F. Fernández-Alonso, B. D. Bean, J. D. Ayers, A. E. Pomerantz, R. N. Zare, and E. Wrede, Nature (London) 416, 67 (2002)]. This paper presents the first derivation of this formulation for atom-plus-diatom reactive scattering, and explains its relation to conventional time-independent reactive scattering. We generalize recent results for spherical-particle scattering [S. C. Althorpe, Phys. Rev. A 69, 042702 (2004)] to atom-rigid-rotor scattering in the space-fixed frame, atom-rigid-rotor scattering in the body-fixed frame, and finally A+BC rearrangement scattering. The reactive scattering is initiated by a plane wave packet, describing the A+BC reagents in center-of-mass scattering coordinates, and is detected by projecting onto a series of AC+B (or AB+C) plane wave ``probe'' packets. The plane wave packets are localized at the closest distance from the scattering center at which the interaction potential can be neglected. The time evolution of the initial plane wave packet provides a clear visualization of the scattering into space of the reaction products. The projection onto the probe packets yields the time-independent, state-to-state scattering amplitude, and hence the differential cross section. We explain how best to implement the PWP approach in a numerical computation, and illustrate this with a detailed application to the H+D2 reaction.

Althorpe, Stuart C.

2004-07-01

5

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

6

Semiclassical Gaussian wave packet dynamics for collinear reactive scattering  

SciTech Connect

The dynamics of collinear exchange reactions is treated within a semiclassical Gaussian wave packet (GWP) description. Two extensions to the previous methodology of GWP dynamics are presented. The first involves the evaluation of the interaction picture wave function propagators directly via the GWP solution to the time-dependent Schroedinger equation. The second involves use of a sum of GWPs to represent the initial translational plane wave on a finite interval. As usual, the vibrational wave function is also represented as a sum of GWPs, where the expansion coefficients are chosen to yield the desired initial vibrational state. The limitations of the previous GWP dynamical methods as applied to the reactive scattering problem are pointed out and the solutions provided by the present extensions are discussed. Results for the H+H/sub 2/ collinear exchange reaction using the Porter--Karplus II potential energy surface are shown.

Kress, J.D.; DePristo, A.E.

1988-09-01

7

Crossed-molecular-beams reactive scattering of oxygen atoms  

SciTech Connect

The reactions of O(/sup 3/P) with six prototypical unsaturated hydrocarbons, and the reaction of O(/sup 1/D) with HD, have been studied in high-resolution crossed-molecular-beams scattering experiments with mass-spectrometric detection. The observed laboratory-product angular and velocity distributions unambiguously identify parent-daughter ion pairs, distinguish different neutral sources of the same ion, and have been used to identify the primary products of the reactions. The derived center-of-mass product angular and translational energy distributions have been used to elucidate the detailed reaction dynamics. These results demonstrate that O(/sup 3/P)-unsaturated hydrocarbon chemistry is dominated by single bond cleavages, leading to radical products exclusively.

Baseman, R.J.

1982-11-01

8

Modern integral equation techniques for quantum reactive scattering theory  

SciTech Connect

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{sub 2} {yields} H{sub 2}/DH + H reaction, and use the time independent integral equation technique in quantum reactive scattering theory. We examine the sensitivity of H+H{sub 2} state resolved integral cross sections {sigma}{sub v{prime}j{prime},vj}(E) for the transitions (v = 0,j = 0) to (v{prime} = 1,j{prime} = 1,3), to the difference between the Liu-Siegbahn-Truhlar-Horowitz (LSTH) and double many body expansion (DMBE) ab initio potential energy surfaces (PES). This sensitivity analysis is performed to determine the origin of a large discrepancy between experimental cross sections with sharply peaked energy dependence and theoretical ones with smooth energy dependence. We find that the LSTH and DMBE PESs give virtually identical cross sections, which lends credence to the theoretical energy dependence.

Auerbach, S.M.

1993-11-01

9

Characterization of corrosion products in the permeable reactive barriers  

Microsoft Academic Search

The impact of geochemical processes and microbial activity has been a major concern for the long-term performance of reactive\\u000a iron barriers because corrosion products and precipitates during the water treatment with reactive materials will decrease\\u000a the reactivity and permeability of the iron bed. This study characterizes corrosion products in reactive iron barrier as well\\u000a as evaluates the effect of the

Y. Roh; S. Y. Lee; M. P. Elless

2000-01-01

10

Application of the Interaction Picture to Reactive Scattering in One Dimension.  

National Technical Information Service (NTIS)

The interaction picture is used together with the channel-packet method in a new time-dependent approach to compute reactive scattering matrix elements. The channel-packet method enables the use of the interaction picture for computing reactive S-matrix e...

M. J. MacLachlan

1999-01-01

11

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

12

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

13

Time-dependent quantum reactive scattering in hyperspherical coordinates  

NASA Astrophysics Data System (ADS)

We present a time-dependent hyperspherical, wave packet method for calculating three atom state-to-state S-matrix elements. The wave packet is propagated in time using adiabatically adjusting, principal axes hyperspherical (APH) coordinates that treat all arrangement channels equivalently, allowing the simultaneous analysis of the products in all three arrangement channels. We take advantage of the symmetry of the potential energy surface and decompose the initial wave packet into its component irreducible representations, propagating each component separately. Each packet is analyzed by projecting it onto the hyperspherical basis at a fixed, asymptotic hyperradius, and irreducible representation dependent S-matrix elements are obtained by matching the hyperspherical projections to symmetry-adapted Jacobi coordinate boundary conditions. We obtain arrangement channel-dependent S-matrix elements as linear combinations of the irreducible representation dependent elements. We derive and implement a new three-dimensional Sylvester-like algorithm that reduces the number of multiplications required to apply the Hamiltonian to the wave packet, dramatically increasing the computational efficiency. A convergence study is presented to show the behavior of the results as the initial parameters are varied and to determine the values of those parameters that give accurate results. State-to-state H + H2 and F + H2 results for zero total angular momentum are presented and show excellent agreement with time-independent benchmark results.

Crawford, Jeffrey James

14

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

15

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

16

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

17

Reactivity margins in heavy water moderated production reactors  

SciTech Connect

The design of the reactor core and components of the heavy water moderated reactors at the Savannah River Plant (SFP) can be varied to produce a number of isotopes. For the past decade, the predominant reactor core design has been the enriched-depleted lattice. In this lattice, fuel assemblies of highly enriched uranium and target assemblies of depleted uranium, which produce plutonium, occupy alternate lattice positions. This heterogeneous lattice arrangement and a nonuniform control rod distribution result in a reactor core that requires sophisticated calculational methods for accurate reactivity margin and power distribution predictions. For maximum accuracy, techniques must exist to provide a base of observed data for the calculations. Frequent enriched-depleted lattice design changes are required as product demands vary. These changes provided incentive for the development of techniques to combine the results of calculations and observed reactivity data to accurately and conveniently monitor reactivity margins during operation.

Benton, F.D.

1981-11-01

18

Jet production in muon scattering at Fermilab E665  

SciTech Connect

Measurements of multi-jet production rates from Muon-Nucleon and Muon-Nuclei scattering at Fermilab-E665 are presented. Jet rates are defined by the JADE clustering algorithm. Rates in Muon-Nucleon deep-inelastic scattering are compared to Monte Carlo model predictions. Preliminary results from jet production on heavy targets, in the shadowing region, show a higher suppression of two-forward jets as compared to one-forward jet production.

Salgado, C.W.; E665 Collaboration

1993-11-01

19

Jet production in muon scattering at Fermilab E665  

Microsoft Academic Search

Measurements of multi-jet production rates from Muon-Nucleon and Muon-Nuclei scattering at Fermilab-E665 are presented. Jet rates are defined by the JADE clustering algorithm. Rates in Muon-Nucleon deep-inelastic scattering are compared to Monte Carlo model predictions. Preliminary results from jet production on heavy targets, in the shadowing region, show a higher suppression of two-forward jets as compared to one-forward jet production.

C. W. Salgado

1993-01-01

20

Reactive ion etching-assisted surface-enhanced Raman scattering measurements on the single nanoparticle level  

NASA Astrophysics Data System (ADS)

Single-nanoparticle surface-enhanced Raman scattering (SERS) measurement is of essential importance for both fundamental research and practical applications. In this work, we develop a class of single-particle SERS approaches, i.e., reactive ion etching (RIE)-assisted SERS measurements correlated with scanning electron microscopy (SEM) strategy (RIE/SERS/SEM), enabling precise and high-resolution identification of single gold nanoparticle (AuNP) in facile and reliable manners. By using AuNP-coated silicon wafer and quartz glass slide as models, we further employ the developed RIE/SERS/SEM method for interrogating the relationship between SERS substrates and enhancement factor (EF) on the single particle level. Together with theoretical calculation using an established finite-difference-time-domain (FDTD) method, we demonstrate silicon wafer as superior SERS substrates, facilitating improvement of EF values.

Wang, Si-Yi; Jiang, Xiang-Xu; Xu, Ting-Ting; Wei, Xin-Pan; Lee, Shuit-Tong; He, Yao

2014-06-01

21

Sudden rotation reactive scattering: Theory and application to 3-D H+H/sub 2/  

SciTech Connect

An approximate quantum mechanical theory of reactive scattering is presented and applied to the H+H/sub 2/ reaction in three dimensions. Centrifugal sudden and rotational sudden approximations are made in each arrangement channel, however, vibrational states are treated in a fully coupled manner. Matching of arrangement channel wave functions is done where the arrangement channel centrifugal potentials are equal. This matching is particularly appropriate for collinearly favored reactions. Integral and differential cross sections are calculated for the H+H/sub 2/ reaction for H/sub 2/ in the ground and first excited vibrational states. These calculations employ the Porter--Karplus potential energy surface mainly to allow for comparisons with previous accurate and approximate quantal and quasiclassical calculations.

Bowman, J.M.; Lee, K.T.

1980-05-01

22

Algorithm for the Production of Contour Maps from Scattered Data  

Microsoft Academic Search

THE production of contour maps from data measured at a set of points randomly scattered over some given region is a common problem. For example, geologists are interested in the production of trend surfaces and the associated contour maps from data consisting of the x,y map coordinates of bore locations and the corresponding depths below sea level at which a

A. J. Cole

1968-01-01

23

A MATLAB-based finite-element visualization of quantum reactive scattering. I. Collinear atom-diatom reactions.  

PubMed

We restate the application of the finite element method to collinear triatomic reactive scattering dynamics with a novel treatment of the scattering boundary conditions. The method provides directly the reactive scattering wave function and, subsequently, the probability current density field. Visualizing these quantities provides additional insight into the quantum dynamics of simple chemical reactions beyond simplistic one-dimensional models. Application is made here to a symmetric reaction (H+H2), a heavy-light-light reaction (F+H2), and a heavy-light-heavy reaction (F+HCl). To accompany this article, we have written a MATLAB code which is fast, simple enough to be accessible to a wide audience, as well as generally applicable to any problem that can be mapped onto a collinear atom-diatom reaction. The code and user's manual are available for download from http://www2.chem.umd.edu/groups/alexander/FEM. PMID:25028010

Warehime, Mick; Alexander, Millard H

2014-07-14

24

Three dimensional quantum mechanical studies of D+H/sub 2/. -->. HD+H reactive scattering. III. On the ab initio potential energy surface  

SciTech Connect

Three dimensional quantum mechanical calculations are carried out for the reactive scattering of D+H/sub 2/..-->..DH+H on the ab initio potential energy surface calculated by Liu and Siegbahn and fitted by Truhlar and Horowitz. The differential and total cross sections as well as the S matrix elements are obtained from the adiabatic distorted wave method. Threshold energy, cross sections and product distributions over final states are all in good agreement with experimental measurements. Results are also compared with the corresponding ones obtained on the Porter--Karplus and the Yates--Lester semi-empirical surfaces.

Yung, Y.Y.; Choi, B.H.; Tang, K.T.

1980-01-01

25

Reactivities and products of free radical oxidation of cholestadienols.  

PubMed

7-Dehydrocholesterol (7-DHC) is the most oxidizable lipid molecule reported to date, with a propagation rate constant for free radical peroxidation that is 200 times that of cholesterol. To better understand the high reactivity of 7-DHC and elucidate the reaction mechanism, we synthesized conjugated and skipped nonconjugated cholestadienols that would give one of the two putative pentadienyl-radical intermediates formed in 7-DHC peroxidation. The additional dienols include 6,8(9)-dienol, 5,8(14)-dienol, 6,8(14)-dienol, and the biologically important 8-dehydrocholesterol (8-DHC; 5,8(9)-dienol). We found that all of the dienols are significantly (at least 40 times) more reactive than cholesterol. Among them, dienols leading to the formation of the pentadienyl radical in ring B (termed endo-B) of the sterol are more reactive than those leading to the pentadienyl radical spanning rings B and C (termed exo-B). By comparing the oxysterol profile formed from 7-DHC and those formed from 8-DHC and 5,8(14)-dienol, products formed from abstraction of the hydrogen atoms at C-9 and C-14 (H-9 or H-14 mechanism) were clearly differentiated. When the oxidation was carried out in the presence of the good hydrogen atom donor ?-tocopherol, the oxysterol profile of 7-DHC peroxidation differed distinctly from the profile observed in the absence of the antioxidant and resembles more closely the profile observed in biological systems. This study suggests that oxidative stress and the accumulation of oxysterols should be considered as two key factors in cholesterol biosynthesis or metabolism disorders, where dienyl sterol intermediates are accumulated. PMID:24625033

Xu, Libin; Porter, Ned A

2014-04-01

26

Quantum State-Resolved Reactive and Inelastic Scattering at Gas-Liquid and Gas-Solid Interfaces  

NASA Astrophysics Data System (ADS)

Quantum state-resolved reactive and inelastic scattering at gas-liquid and gas-solid interfaces has become a research field of considerable interest in recent years. The collision and reaction dynamics of internally cold gas beams from liquid or solid surfaces is governed by two main processes, impulsive scattering (IS), where the incident particles scatter in a few-collisions environment from the surface, and trapping-desorption (TD), where full equilibration to the surface temperature (T{TD}? T{s}) occurs prior to the particles' return to the gas phase. Impulsive scattering events, on the other hand, result in significant rotational, and to a lesser extent vibrational, excitation of the scattered molecules, which can be well-described by a Boltzmann-distribution at a temperature (T{IS}>>T{s}). The quantum-state resolved detection used here allows the disentanglement of the rotational, vibrational, and translational degrees of freedom of the scattered molecules. The two examples discussed are (i) reactive scattering of monoatomic fluorine from room-temperature ionic liquids (RTILs) and (ii) inelastic scattering of benzene from a heated (˜500 K) gold surface. In the former experiment, rovibrational states of the nascent HF beam are detected using direct infrared absorption spectroscopy, and in the latter, a resonace-enhanced multi-photon-ionization (REMPI) scheme is employed in combination with a velocity-map imaging (VMI) device, which allows the detection of different vibrational states of benzene excited during the scattering process. M. E. Saecker, S. T. Govoni, D. V. Kowalski, M. E. King and G. M. Nathanson Science 252, 1421, 1991. A. M. Zolot, W. W. Harper, B. G. Perkins, P. J. Dagdigian and D. J. Nesbitt J. Chem. Phys 125, 021101, 2006. J. R. Roscioli and D. J. Nesbitt Faraday Disc. 150, 471, 2011.

Grütter, Monika; Nelson, Daniel J.; Nesbitt, David J.

2012-06-01

27

Towards a specific reaction parameter density functional for reactive scattering of H2 from Pd(111)  

NASA Astrophysics Data System (ADS)

Recently, an implementation of the specific reaction parameter (SRP) approach to density functional theory (DFT) was used to study several reactive scattering experiments of H2 on Cu(111). It was possible to obtain chemical accuracy (1 kcal/mol ? 4.2 kJ/mol), and therefore, accurately model this paradigmatic example of activated H2 dissociation on a metal surface. In this work, the SRP-DFT methodology is applied to the dissociation of hydrogen on a Pd(111) surface, in order to test whether the SRP-DFT approach is also applicable to non-activated H2-metal systems. In the calculations, the Born-Oppenheimer static surface approximations are used. A comparison to molecular beam sticking experiments, performed at incidence energies ?125 meV, on H2 + Pd(111) suggested the PBE-vdW [where the Perdew, Burke, and Ernzerhof (PBE) correlation is replaced by van der Waals correlation] functional as a candidate SRP density functional describing the reactive scattering of H2 on Pd(111). Unfortunately, quantum dynamics calculations are not able to reproduce the molecular beam sticking results for incidence energies <125 meV. From a comparison to initial state-resolved (degeneracy averaged) sticking probabilities it seems clear that for H2 + Pd(111) dynamic trapping and steering effects are important, and that these effects are not yet well modeled with the potential energy surfaces considered here. Applying the SRP-DFT method to systems where H2 dissociation is non-activated remains difficult. It is suggested that a density functional that yields a broader barrier distribution and has more non-activated pathways than PBE-vdW (i.e., non-activated dissociation at some sites but similarly high barriers at the high energy end of the spectrum) should allow a more accurate description of the available experiments. Finally, it is suggested that new and better characterized molecular beam sticking experiments be done on H2 + Pd(111), to facilitate the development of a more accurate theoretical description of this system.

Boereboom, J. M.; Wijzenbroek, M.; Somers, M. F.; Kroes, G. J.

2013-12-01

28

Geochemical production of reactive oxygen species from biogeochemically reduced fe.  

PubMed

The photochemical reduction of Fe(III) complexes to Fe(II) is a well-known initiation step for the production of reactive oxygen species (ROS) in sunlit waters. Here we show a geochemical mechanism for the same in dark environments based on the tidally driven, episodic movement of anoxic groundwaters through oxidized, Fe(III) rich sediments. Sediment samples were collected from the top 5 cm of sediment in a saline tidal creek in the estuary at Murrell's Inlet, South Carolina and characterized with respect to total Fe, acid volatile sulfides, and organic carbon content. These sediments were air-dried, resuspended in aerated solution, then exposed to aqueous sulfide at a range of concentrations chosen to replicate the conditions characteristic of a tidal cycle, beginning with low tide. No detectable ROS production occurred from this process in the dark until sulfide was added. Sulfide addition resulted in the rapid production of hydrogen peroxide, with maximum concentrations of 3.85 ?M. The mechanism of hydrogen peroxide production was tested using a simplified three factor representation of the system based on hydrogen sulfide, Fe(II) and Fe(III). The resulting predictive model for maximum hydrogen peroxide agreed with measured hydrogen peroxide in field-derived samples at the 95% level of confidence, although with a persistent negative bias suggesting a minor undiscovered peroxide source in sediments. PMID:24597860

Murphy, Sarah A; Solomon, Benson M; Meng, Shengnan; Copeland, Justin M; Shaw, Timothy J; Ferry, John L

2014-04-01

29

Electrophysiology of Reactive Oxygen Production in Signaling Endosomes  

PubMed Central

Abstract Endosome trafficking and function require acidification by the vacuolar ATPase (V-ATPase). Electrogenic proton (H+) transport reduces the pH and creates a net positive charge in the endosomal lumen. Concomitant chloride (Cl?) influx has been proposed to occur via ClC Cl?/H+ exchangers. This maintains charge balance and drives Cl? accumulation, which may itself be critical to endosome function. Production of reactive oxygen species (ROS) in response to cytokines occurs within specialized endosomes that form in response to receptor occupation. ROS production requires an NADPH oxidase (Nox) and the ClC-3 Cl?/H+ exchanger. Like the V-ATPase, Nox activity is highly electrogenic, but separates charge with an opposite polarity (lumen negative). Here we review established paradigms of early endosomal ion transport focusing on the relation between the V-ATPase and ClC proteins. Electrophysiologic constraints on Nox-mediated vesicular ROS production are then considered. The potential for ClC-3 to participate in charge neutralization of both proton (V-ATPase) and electron (Nox) transport is discussed. It is proposed that uncompensated charge separation generated by Nox enzymatic activity could be used to drive secondary transport into negatively charged vesicles. Further experimentation will be necessary to establish firmly the biochemistry and functional implications of endosomal ROS production. Antioxid. Redox Signal. 11, 1335–1347.

Moreland, Jessica G.; Miller, Francis J.

2009-01-01

30

Phosphate enhances reactive oxygen species production and suppresses osteoblastic differentiation.  

PubMed

Phosphate has been shown to work as a signaling molecule in several cells including endothelial cells and chondrocytes. However, it is largely unknown how phosphate affects osteoblastic cells. In the present study, we investigated the effects of phosphate on reactive oxygen species (ROS) production and osteoblastic differentiation in murine osteoblastic MC3T3-E1 cells. Phosphate increased production of ROS in MC3T3-E1 cells and the inhibitors of sodium-phosphate cotransporter and NADPH oxidase suppressed ROS production by phosphate. Silencing Nox1 and Nox4 also inhibited the increase of ROS by phosphate. Phosphate also decreased alkaline phosphatase activity induced by bone morphogenetic protein 2 and this inhibition was abrogated by an inhibitor of NADPH oxidase. Furthermore, phosphate decreased the expression of osteoblastic marker genes in MC3T3-E1 cells. These results indicate that phosphate suppresses osteoblastic differentiation at least in part by enhancing ROS production in MC3T3-E1 cells. PMID:24052209

Okamoto, Takaaki; Taguchi, Manabu; Osaki, Tomoko; Fukumoto, Seiji; Fujita, Toshiro

2014-07-01

31

Heavy quark production in deep-inelastic scattering at HERA.  

SciTech Connect

We discuss two topics in the production of heavy quarks in deep-inelastic scattering: the next-to-leading order Monte-Carlo HVQDIS and the next-to-leading logarithmic resummation of soft gluon effects, including estimates of next-to-next-to-leading order corrections therefrom.

Harris, B. W.; Laenen, E.; Moch, S.; Smith, J.

1999-06-02

32

Production and detection of reactive oxygen species (ROS) in cancers.  

PubMed

Reactive oxygen species include a number of molecules that damage DNA and RNA and oxidize proteins and lipids (lipid peroxydation). These reactive molecules contain an oxygen and include H(2;)O(2;) (hydrogen peroxide), NO (nitric oxide), O(2;)(-) (oxide anion), peroxynitrite (ONOO(-)), hydrochlorous acid (HOCl), and hydroxyl radical (OH(-)). Oxidative species are produced not only under pathological situations (cancers, ischemic/reperfusion, neurologic and cardiovascular pathologies, infectious diseases, inflammatory diseases, autoimmune diseases , etc…) but also during physiological (non-pathological) situations such as cellular metabolism. Indeed, ROS play important roles in many cellular signaling pathways (proliferation, cell activation, migration etc..). ROS can be detrimental (it is then referred to as "oxidative and nitrosative stress") when produced in high amounts in the intracellular compartments and cells generally respond to ROS by upregulating antioxidants such as superoxide dismutase (SOD) and catalase (CAT), glutathione peroxidase (GPx) and glutathione (GSH) that protects them by converting dangerous free radicals to harmless molecules (i.e. water). Vitamins C and E have also been described as ROS scavengers (antioxidants). Free radicals are beneficial in low amounts. Macrophage and neutrophils-mediated immune responses involve the production and release of NO, which inhibits viruses, pathogens and tumor proliferation. NO also reacts with other ROS and thus, also has a role as a detoxifier (ROS scavenger). Finally NO acts on vessels to regulate blood flow which is important for the adaptation of muscle to prolonged exercise. Several publications have also demonstrated that ROS are involved in insulin sensitivity. Numerous methods to evaluate ROS production are available. In this article we propose several simple, fast, and affordable assays; these assays have been validated by many publications and are routinely used to detect ROS or its effects in mammalian cells. While some of these assays detect multiple ROS, others detect only a single ROS. PMID:22127014

Wu, Danli; Yotnda, Patricia

2011-01-01

33

BKLT equations for reactive scattering. I. Theory and application to three finite mass atom systems  

SciTech Connect

The BKLT equations for reactive scattering are considered in detail, both from a formal and computational point of view. The equations are very attractive because they do not require any matching of wave functions. It is shown how these equations may be solved for a general collinear three-finite mass atom system. Special care is taken to treat subleties in the theory arising from restrictions on the ranges of the vibrational coordinate of the various diatoms due to the skewing angle being less than 90/sup 0/. In addition, the structure of the equations is explored in detail since this has significance for their optimum solution. It is found that the structure of the equations for asymmetric systems leads to important redutions in the size of the matrix which must be inverted within the present, nonpropagative method. Other solution methods are also discussed to some extent. Finally, the method is illustrated by an application to the H+H/sub 2/ exchange reaction with the Porter--Karplus potential surface. The results obtained agree well with those obtained earlier by Diestler using a close coupling, propagation procedure.

Shima, Y.; Kouri, D.J.; Baer, M.

1983-06-01

34

Conceptual design of a reactive distillation process for ultra-low sulfur diesel production  

Microsoft Academic Search

Based on a thermodynamic analysis in terms of reaction-separation feasibility, a conceptual design of a reactive distillation column for ultra-low sulfur diesel production has been developed. The thermodynamic analysis considers the computation of reactive and non-reactive residue curve maps for a mixture that models the sulfured diesel fuel. The visualization of the reactive residue curves is posed in terms of

Tomás Viveros-García; J. Alberto Ochoa-Tapia; Ricardo Lobo-Oehmichen; J. Antonio de los Reyes-Heredia; Eduardo S. Pérez-Cisneros

2005-01-01

35

In situ analysis of size distribution of nano-particles in reactive plasmas using two dimensional laser light scattering method  

Microsoft Academic Search

We have developed a simple in-situ method for measuring the size distribution (the mean size (mean diameter) and size dispersion) of nano-particles generated in reactive plasmas using the 2 dimensional laser light scattering (2DLLS) method. The principle of the method is based on thermal coagulation of the nano-particles, which occurs after the discharge is turned off, and the size and

K Kamataki; Y Morita; M Shiratani; K Koga; G Uchida; N Itagaki

2012-01-01

36

Neutral strange particle production in deep inelastic scattering at HERA  

Microsoft Academic Search

This paper presents measurements ofK0 and ? production in neutral current, deep inelastic scattering of 26.7 GeV electrons and 820 GeV protons in the kinematic range 10Q22, 0.0003xy>0.04. Average multiplicities forK0 and ? production are determined for transverse momentapT>0.5 GeV and pseudorapidities |?|e+e- experiments. The production properties ofK0' s in events with and without a large rapidity gap with respect

M. Derick; D. Krakauer; S. Magill; D. Mikunas; B. Musgrave; J. Repond; R. Stanek; R. L. Talaga; H. Zhang; R. Ayad; 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; F. 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; K. Heinloth; E. Hilger; H.-P. Jakob; U. F. Katz; S. M. Mari; A. Mass; S. Mengel; J. Mollen; E. Paul; Ch. Rembser; 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. J. Tapper; S. S. Wilson; R. Yoshida; R. R. Rau; M. Arneodo; L. Iannotti; M. Schioppa; G. Susinno; A. Bernstein; A. Caldwell; N. Cartiglia; 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. Adamezyk; B. Bednarek; K. Jelen; D. Kisielewska; T. Kowalski; E. Rulikowska-Zarebska; L. Suszycki; J. Zajac; A. Kotanski; M. Przybycien; L. 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; 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; J. Mainusch; O. Manczak; T. Monteiro; 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. C. K. 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; J. 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. 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; J. P. Fernandez; R. Graciani; J. M. Hernández; L. Hervás; L. Labarga; M. Martinez; 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; A. Byrne; R. J. Cashmore; A. M. Cooper-Sarkar; R. C. E. Devenish; N. Harnew; M. Lancaster; L. Lindemann; J. D. McFall; C. Nath; V. A. Noyes; A. Quadt; J. R. Tickner; H. Uijterwaal; R. Walczak; D. S. Waters; F. F. Wilson; T. Yip; G. Abbrendi; 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; E. Barberis; 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; O. Schwarzer; 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

1995-01-01

37

Hadron production in diffractive deep-inelastic scattering  

Microsoft Academic Search

Characteristics of hadron production in diffractive deep-inelastic positron-proton scattering are studied using data collected in 1994 by the H1 experiment at HERA. The following distributions are measured in the centre-of-mass frame of the photon dissociation system: the hadronic energy flow, the Feynman-x (xF) variable for charged particles, the squared transverse momentum of charged particles (pT?2), and the mean pT?2 as

C. Adloff; S. Aid; M. Anderson; V. Andreev; B. Andrieu; V. Arkadov; C. Arndt; I. Ayyaz; A. Babaev; J. Bähr; P. Baranov; E. Barrelet; R. Barschke; W. Bartel; U. Bassler; P. Bate; M. Beck; A. Beglarian; H.-J. Behrend; C. Beier; A. Belousov; Ch. Berger; G. Bernardi; G. Bertrand-Coremans; R. Beyer; P. Biddulph; J. C. Bizot; K. Borras; V. Boudry; A. Braemer; W. Braunschweig; V. Brisson; D. P. Brown; W. Brückner; P. Bruel; D. Bruncko; C. Brune; J. Bürger; F. W. Büsser; A. Buniatian; S. Burke; G. Buschhorn; D. Calvet; A. J. Campbell; T. Carli; E. Chabert; M. Charlet; D. Clarke; B. Clerbaux; S. Cocks; J. G. Contreras; C. Cormack; J. A. Coughlan; M.-C. Cousinou; B. E. Cox; G. Cozzika; J. Cvach; J. B. Dainton; W. D. Dau; K. Daum; M. David; A. De Roeck; E. A. De Wolf; B. Delcourt; C. Diaconu; M. Dirkmann; P. Dixon; W. Dlugosz; K. T. Donovan; J. D. Dowell; A. Droutskoi; J. Ebert; G. Eckerlin; D. Eckstein; V. Efremenko; S. Egli; R. Eichler; F. Eisele; E. Eisenhandler; M. Enzenberger; A. B. Fahr; L. Favart; A. Fedotov; R. Felst; J. Feltesse; F. Ferrarotto; K. Flamm; M. Fleischer; G. Flügge; A. Fomenko; J. Formánek; G. Franke; E. Gabathuler; K. Gabathuler; F. Gaede; J. Garvey; M. Gebauer; R. Gerhards; A. Glazov; L. Goerlich; N. Gogitidze; M. Goldberg; I. Gorelov; C. Grab; H. Grässler; T. Greenshaw; R. K. Griffiths; G. Grindhammer; C. Gruber; T. Hadig; D. Haidt; L. Hajduk; T. Haller; M. Hampel; V. Haustein; W. J. Haynes; B. Heinemann; G. Heinzelmann; R. C. W. Henderson; S. Hengstmann; H. Henschel; R. Heremans; I. Herynek; K. Hewitt; K. H. Hiller; C. D. Hilton; J. Hladký; M. Höppner; D. Hoffmann; T. Holtom; R. Horisberger; V. L. Hudgson; M. Hütte; M. Ibbotson; Ç. ??sever; H. Itterbeck; M. Jacquet; J. Janoth; D. M. Jansen; L. Jönsson; D. P. Johnson; H. Jung; M. Kander; D. Kant; 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; J. H. Köhne; H. Kolanoski; S. D. Kolya; V. Korbel; P. Kostka; S. K. Kotelnikov; T. Krämerkämper; M. W. Krasny; H. Krehbiel; D. Krücker; A. Küpper; H. Küster; M. Kuhlen; T. Kur?a; B. Laforge; R. Lahmann; M. P. J. Landon; W. Lange; U. Langenegger; A. Lebedev; M. Lehmann; F. Lehner; V. Lemaitre; S. Levonian; M. Lindstroem; J. Lipinski; B. List; G. Lobo; V. Lubimov; D. Lüke; L. Lytkin; N. Magnussen; H. Mahlke-Krüger; E. Malinovski; R. Mara?ek; P. Marage; J. Marks; R. Marshall; G. Martin; R. Martin; H.-U. Martyn; J. Martyniak; S. J. Maxfield; S. J. McMahon; T. R. McMahon; A. Mehta; K. Meier; P. Merkel; F. Metlica; A. Meyer; H. Meyer; J. Meyer; P.-O. Meyer; A. Migliori; S. Mikocki; D. Milstead; J. Moeck; R. Mohr; S. Mohrdieck; F. Moreau; J. V. Morris; E. Mroczko; D. Müller; K. Müller; P. Mur??n; 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; O. Nix; G. Nowak; T. Nunnemann; H. Oberlack; J. E. Olsson; D. Ozerov; P. Palmen; E. Panaro; A. Panitch; C. Pascaud; S. Passaggio; G. D. Patel; H. Pawletta; E. Peppel; J. P. Phillips; A. Pieuchot; D. Pitzl; R. Pöschl; G. Pope; B. Povh; K. Rabbertz; P. Reimer; B. Reisert; H. Rick; S. Riess; E. Rizvi; P. Robmann; R. Roosen; K. Rosenbauer; A. Rostovtsev; F. Rouse; C. Royon; S. Rusakov; K. Rybicki; D. P. C. Sankey; P. Schacht; J. Scheins; S. Schiek; S. Schleif; P. Schleper; W. von Schlippe; D. Schmidt; G. Schmidt; L. Schoeffel; A. Schöning; V. Schröder; H.-C. Schultz-Coulon; B. Schwab; F. Sefkow; A. Semenov; V. Shekelyan; I. Sheviakov; L. N. Shtarkov; G. Siegmon; U. Siewert; Y. Sirois; I. O. Skillicorn; T. Sloan; P. Smirnov; M. Smith; V. Solochenko; Y. Soloviev; A. Specka; J. Spiekermann; H. Spitzer; F. Squinabol; P. Steffen; R. Steinberg; J. Steinhart; B. Stella; A. Stellberger; J. Stiewe; K. Stolze; U. Straumann; W. Struczinski; J. P. Sutton; M. Swart; S. Tapprogge; M. Taševský; V. Tchernyshov; S. Tchetchelnitski; J. Theissen; G. Thompson; P. D. Thompson; N. Tobien; R. Todenhagen; P. Truöl; G. Tsipolitis; J. Turnau; E. Tzamariudaki; S. Udluft; A. Usik; S. Valkár; A. Valkárová; C. Vallée; P. Van Esch; P. Van Mechelen; Y. Vazdik; G. Villet; K. Wacker; R. Wallny; T. Walter; B. Waugh; G. Weber; M. Weber; D. Wegener; A. Wegner; T. Wengler; M. Werner; L. R. West; S. Wiesand; T. Wilksen; S. Willard; M. Winde; G.-G. Winter; C. Wittek; E. Wittmann; M. Wobisch; H. Wollatz; E. Wünsch; J. Žá?ek; J. Zálešák; Z. Zhang; A. Zhokin; P. Zini; F. Zomer; J. Zsembery; M. Zurnedden

1998-01-01

38

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

39

Reactivity Impact of 2H and 16O Elastic Scattering Nuclear Data on Critical Systems with Heavy Water  

NASA Astrophysics Data System (ADS)

The accuracy of deuterium nuclear data is important for reactor physics simulations of heavy water (D2O) reactors. The elastic neutron scattering cross section data at thermal energies, ?s,th, have been observed to have noticeable impact on the reactivity values in simulations of critical systems involving D2O. We discuss how the uncertainties in the thermal scattering cross sections of 2H(n,n)2H and 16O(n,n)16O propagate to the uncertainty of the calculated neutron multiplication factor, keff, in thermal critical assemblies with heavy water neutron moderator/reflector. The method of trial evaluated nuclear data files, in which specific cross sections are individually perturbed, is used to calculate the sensitivity coefficients of keff to the microscopic nuclear data, such as ?s(E) characterized by ?s,th. Large reactivity differences of up to ? 5-10 mk (500-1000 pcm) were observed using 2H and 16O data files with different elastic scattering data in MCNP5 simulations of the LANL HEU heavy-water solution thermal critical experiments included in the ICSBEP handbook.

Roubtsov, D.; Kozier, K. S.; Chow, J. C.; Plompen, A. J. M.; Kopecky, S.; Svenne, J. P.; Canton, L.

2014-04-01

40

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

41

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

PubMed

Molecular electronic excitation in (O(2))(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 (O(2))(2) cluster model in various configurations reveal the emergence of possible pathways for the generation of electronically excited singlet O(2) molecules upon cluster compression and vibrational excitation, due to electronic curve-crossing and spin-orbit coupling. Extrapolation of the model (O(2))(2) results to larger clusters suggests a dramatic increase in the population of electronically excited O(2) 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 O(2) molecules. Extensive molecular dynamics simulations of (O(2))(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." PMID:21322678

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

2011-02-14

42

Neutral strange particle production in deep inelastic scattering at HERA  

NASA Astrophysics Data System (ADS)

This paper presents measurements of K 0 and ? production in neutral current, deep inelastic scattering of 26.7 GeV electrons and 820 GeV protons in the kinematic range 10< Q 2<640 GeV2, 0.0003< x<0.01, and y>0.04. Average multiplicities for K 0 and ? production are determined for transverse momenta p T>0.5 GeV and pseudorapidities |?|<1.3. The multiplicities favour a stronger strange to light quark suppression in the fragmentation chain than found in e + e - experiments. The production properties of K 0' s in events with and without a large rapidity gap with respect to the proton direction are compared. The ratio of neutral K 0' s to charged particles per event in the measured kinematic range is, within the present statistics, the same in both samples.

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

1995-03-01

43

Reactive Oxygen Species Production by the Spermatozoa of Patients With Idiopathic Infertility: Relationship to Seminal Plasma Antioxidants  

Microsoft Academic Search

PurposeWe attempted to determine reactive oxygen species production by the spermatozoa of patients with idiopathic infertility and healthy donors, and observe whether increased production was due to decreased seminal plasma reactive oxygen species scavengers.

Ilter Alkan; Ferruh Simsek; Goncagul Haklar; Ertan Kervancioglu; Hakan Ozveri; Suha Yalcin; Atif Akdas

1997-01-01

44

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

45

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

46

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

47

Hydrogen peroxide production from reactive liposomes encapsulating enzymes  

Microsoft Academic Search

Reactive cationic and anionic liposomes have been prepared from mixtures of dimyristoylphosphatidylcholine (DMPC) and cholesterol incorporating dimethyldioctadecylammonium bromide and DMPC incorporating phosphatidylinositol, respectively. The liposomes were prepared by the vesicle extrusion technique and had the enzymes glucose oxidase (GO) encapsulated in combination with horseradish peroxidase (HRP) or lactoperoxidase (LPO). The generation of hydrogen peroxide from the liposomes in response to

Michael Kaszuba; Malcolm N. Jones

1999-01-01

48

Studies of the Kazan Aeronautics Institute-Scatter Indicatrices of Oxide Particles in Combustion Products.  

National Technical Information Service (NTIS)

It is necessary to know the angular distribution of scattered radiation (scatter indicatrix) when studying phenomena of energy transfer of thermal radiation in combustion products containing solid or liquid particles of condensed aluminum, magnesium, and ...

V. E. Alemasov V. Y. Klabukov

1974-01-01

49

Exclusive meson pair production in ?*? scattering at small momentum transfer  

NASA Astrophysics Data System (ADS)

We study the exclusive production of ?? and ?? in hard ?*? scattering in the forward kinematical region where the virtuality of one photon provides us with a hard scale in the process. The newly introduced concept of Transition Distribution Amplitudes (TDA) is used to perform a QCD calculation of these reactions thanks to two simple models for TDAs. Cross sections for ?? and ?? production are evaluated and compared to the possible background from the Bremsstrahlung process. This picture may be tested at intense electron-positron colliders such as CLEO and B factories. The cross section e??e'?0?0 is finally shown to provide a possible determination of the ?0 axial form factor, FA?0, at small t, which seems not to be measurable elsewhere.

Lansberg, J. P.; Pire, B.; Szymanowski, L.

2006-04-01

50

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

51

Mitochondrial reactive oxygen production is dependent on the aromatic hydrocarbon receptor  

Microsoft Academic Search

2,3,7,8-Tetrachlorodibenzo-p-dioxin (dioxin; TCDD) is a pervasive environmental contaminant that induces hepatic and extrahepatic oxidative stress. We have previously shown that dioxin increases mitochondrial respiration-dependent reactive oxygen production. In the present study we examined the dependence of mitochondrial reactive oxygen production on the aromatic hydrocarbon receptor (AHR), cytochrome P450 1A1 (CYP1A1), and cytochrome P450 1A2 (CYP1A2), proteins believed to be important

Albert P Senft; Timothy P Dalton; Daniel W Nebert; Mary Beth Genter; Alvaro Puga; Richard J Hutchinson; J. Kevin Kerzee; Shigeyuki Uno; Howard G Shertzer

2002-01-01

52

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

53

Solution of the Helmholtz Equation on a Square for a Reactive Scattering Model.  

National Technical Information Service (NTIS)

Solutions of the Helmholtz equation ((the second partial derivative with respect to x) + (the second partial derivative with respect to y) + k squared + 1)psi = 0 describing a simple scattering process in an L-shaped region are studied. To obtain the corr...

P. D. Robinson

1969-01-01

54

Energy evolution of the large-t elastic scattering and its correlation with multiparticle production  

SciTech Connect

It is emphasized that the collective dynamics associated with color confinement is dominating over a point-like mechanism related to a scattering of the proton constituents at the currently available values of the momentum transferred in proton elastic scattering at the LHC. Deep-elastic scattering and its role in the dissimilation of the absorptive and reflective asymptotic scattering mechanisms are discussed with emphasis on the experimental signatures associated with the multiparticle production processes.

Troshin, S. M. [Institute for High Energy Physics, Protvino, Moscow Region, 142281 (Russian Federation)

2013-04-15

55

Time resolved small angle x-ray scattering reactivity studies on coals, asphaltenes, and polymers.  

SciTech Connect

The objective of this study is to examine changes in the structures of coals, asphaltenes, and polymers in situ with small angle X-ray scattering (SAXS) during thermal treatments. We have built a SAXS instrument at the Basic Energy Sciences Synchrotrons Radiation Center at the Advanced Photon Source that allows us to obtain scattering data on very small samples and in the millisecond time domain. The Argonne Premium Coal samples, petroleum derived asphaltenes, and polymers with functionality to model fossil fuels were used in this study. The information that can be derived from these experiments includes: changes in fractal dimensionality, surface topology, and size and type of porosity. The information is correlated with other methods on the same samples.

Seifert, S.; Thiyagarajan, P.; Winans, R. E.

1999-07-02

56

Probing coal reactivity by time-resolved small angle x-ray scattering.  

SciTech Connect

The objective of this study is to observe changes in coal structure in situ with small angle X-ray scattering (SAXS) during solvent swelling and during pyrolysis. We have built a SAXS instrument at the Basic Energy Sciences Synchrotrons Research Center at the Advanced Photon Source that allows us to obtain scattering patterns in the millisecond time domain. The eight Argonne Premium Coal samples were used in this study. The information that can be derived from these experiments, such as changes in fractal dimensionality and in size and type of porosity, was found to be very rank-dependent. In the swelling experiments, it was noted that for certain coals, structural changes occurred in just a few minutes.

Winans, R. E.

1999-01-22

57

Collisions of excited alkali atoms with O2. II. Reactive scattering  

Microsoft Academic Search

Inelastic and reactive channels in excited Na atom\\/ O2 molecule collisions have been included into a single model based on multiple crossings between curves of the Na(n,l)–O2, Na+–O?2 (X 2&Pgr;g), and Na+–O?2 (A 2&Pgr;u) systems. Additionally, estimation is provided of the excited ion pair surface Na+–O?2 (A2&Pgr;u) in collinear geometry. This paper is essentially concerned with the reaction of Na(4D)

J. M. Mestdagh; D. Paillard; J. Berlande

1988-01-01

58

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

59

Chemical Characterization and Reactivity of Fuel-Oxidizer Reaction Product  

NASA Technical Reports Server (NTRS)

Fuel-oxidizer reaction product (FORP), the product of incomplete reaction of monomethylhydrazine and nitrogen tetroxide propellants prepared under laboratory conditions and from firings of Shuttle Reaction Control System thrusters, has been characterized by chemical and thermal analysis. The composition of FORP is variable but falls within a limited range of compositions that depend on three factors: the fuel-oxidizer ratio at the time of formation; whether the composition of the post-formation atmosphere is reducing or oxidizing; and the reaction or post-reaction temperature. A typical composition contains methylhydrazinium nitrate, ammonium nitrate, methylammonium nitrate, and trace amounts of hydrazinium nitrate and 1,1-dimethylhydrazinium nitrate. Thermal decomposition reactions of the FORP compositions used in this study were unremarkable. Neither the various compositions of FORP, the pure major components of FORP, nor mixtures of FORP with propellant system corrosion products showed any unusual thermal activity when decomposed under laboratory conditions. Off-limit thruster operations were simulated by rapid mixing of liquid monomethylhydrazine and liquid nitrogen tetroxide in a confined space. These tests demonstrated that monomethylhydrazine, methylhydrazinium nitrate, ammonium nitrate, or Inconel corrosion products can induce a mixture of monomethylhydrazine and nitrogen tetroxide to produce component-damaging energies. Damaging events required FORP or metal salts to be present at the initial mixing of monomethylhydrazine and nitrogen tetroxide.

David, Dennis D.; Dee, Louis A.; Beeson, Harold D.

1997-01-01

60

Reactivity analysis of solution reactors for medical-radioisotope production  

Microsoft Academic Search

One of the primary methods to produce medical isotopes, such as 99Mo, is by irradiation of uranium targets in heterogeneous reactors. Solution reactors present a potential alternative to produce medical isotopes. The medical isotope production reactor concept has been proposed to produce medical isotopes with lower uranium consumption and waste than the corresponding fuel consumption and waste in heterogeneous reactors.

Francisco J. Souto; Robert H. Kimpland

2004-01-01

61

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

62

Electron plasma-wave production by stimulated Raman scattering - Competition with stimulated Brillouin scattering  

Microsoft Academic Search

Temporally and spectrally resolved Thomson scattering in a CO2-laser-plasma interaction experiment was used to identify electron plasma waves driven by stimulated Raman scattering in a low-density preformed plasma. Plasma waves were observed in a Gaussian-shaped plasma whose peak density was in the range (0.01-0.05)n(c), in qualitative agreement with threshold calculations using a convective-amplification model. The plasma waves were observed only

C. J. Walsh; D. M. Villeneuve; H. A. Baldis

1984-01-01

63

Electron plasma-wave production by stimulated Raman scattering: Competition with stimulated Brillouin scattering  

Microsoft Academic Search

We have used temporally and spectrally resolved Thomson scattering in a COâ-laser--plasma interaction experiment to identify electron plasma waves driven by stimulated Raman scattering in a low-density preformed plasma. Plasma waves were observed in a Gaussian-shaped plasma whose peak density was in the range (0.01--0.05)n\\/sub c\\/, in qualitative agreement with threshold calculations using a convective amplification model. The plasma waves

C. J. Walsh; D. M. Villeneuve; H. A. Baldis

1984-01-01

64

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

65

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

66

Optical mapping of myocardial reactive oxygen species production throughout the reperfusion of global ischemia  

NASA Astrophysics Data System (ADS)

Reactive oxygen species (ROS) are short-lived, highly reactive chemical entities that play significant roles in all levels of biology. However, their measurement requires destructive preparation, thereby limiting the continuous measurement of ROS in a living tissue. We develop an optical mapping system to visualize ROS production in an isolated and perfused rat heart. By staining the heart with dihydroethidium (DHE), a 532-nm laser beam is directed to the epicardial surface, where we collect the red fluorescence (>600 nm) for semiquantitative analysis. With this system, ROS production as well as ventricular pressure and ECG in isolated perfused rat hearts are monitored throughout the reperfusion of global ischemia. Ischemia would decrease myocardial ROS production, while reperfusion would immediately result in sustained ROS overproduction. Optical mapping would provide information regarding the spatial distribution and temporal evolution of myocardial ROS production, which would enhance knowledge of the role of free radicals in cardiovascular biology.

Lu, Long-sheng; Liu, Yen-Bin; Sun, Chia-Wei; Lin, Lung-Chun; Su, Ming-jia; Wu, Chau-Chung

2006-03-01

67

Diphenyleneiodonium, an NAD(P)H Oxidase Inhibitor, also Potently Inhibits Mitochondrial Reactive Oxygen Species Production  

Microsoft Academic Search

Diphenyleneiodonium (DPI) has frequently been used to inhibit reactive oxygen species (ROS) production mediated by flavoenzymes, particularly NAD(P)H oxidase. This study was undertaken to examine if DPI could also inhibit production of superoxide and H2O2by mitochondria, the major source of cellular ROS. Detection of mitochondrial superoxide by lucigenin-derived chemiluminescence (CL) with unstimulated monocytes\\/macrophages showed that DPI at concentrations that inhibit

Yunbo Li; Michael A. Trush

1998-01-01

68

Production of a reactive metabolite of troglitazone by electrochemical oxidation performed in nonaqueous medium.  

PubMed

In order to confirm the existence of reactive metabolites by LC-MS/MS analysis, they should be modified into stable compounds, because some reactive metabolites generated by biotransformation induce drug toxicity; however, they are unstable, with very short lives, and cannot be detected in their intact forms. To overcome these problems, electrochemical oxidation of troglitazone was performed in nonaqueous medium, since such reactive compounds are stable in the absence of water. Troglitazone, an antidiabetic agent, was withdrawn from the market because of serious hepatotoxicity in some patients. It has been considered that one or more reactive metabolites are involved in hepatotoxicity, although the mechanism of the adverse reaction is unclear. Using our method of electrochemical oxidation in nonaqueous medium, we obtained a product of troglitazone derivative that may be a clue to clarify the mechanism of toxicity. The product in the reaction mixture was separated by HPLC without chemical modification and detected using UV and ESI-MS. The mass spectrum of its molecular ion showed that it was an o-quinone methide derivative of troglitazone and identified as a reactive metabolite generated by liver microsome oxidation of the drug. The product was stable over 24 h at room temperature in anhydrous acetonitrile, but it reacted with N-(tert-butoxycarbonyl)-L-cystein methylester to produce an adduct that could be identified by its m/z value. Thus, the method of electrochemical oxidation in nonaqueous medium is considered to be useful to prepare and predict reactive metabolites of drugs that are unstable in aqueous medium or in vivo. PMID:19581066

Tahara, Kayoko; Nishikawa, Takashi; Hattori, Yutaka; Iijima, Shiro; Kouno, Yukiko; Abe, Yoshihiro

2009-12-01

69

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

PubMed

Magnetic nanoparticles were prepared by coprecipitating Fe(2+) and Fe(3+) 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) were used for simulation of batch and continuous processes. The analysis demonstrated the possibility of applying this biocatalytic system in the reactive zone using external magnetic fields. This approach implies new advantages in efficient location and use of lipases in column reactors for producing biodiesel. PMID:20716486

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

2010-12-01

70

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

71

Emission of reactive compounds and secondary products from wood-based furniture coatings  

NASA Astrophysics Data System (ADS)

Emissions of organic fragmentation products, so-called "secondary emission products" and reactive species from wood-based furniture coatings have been studied in 1 m 3 test chambers. the climatic conditions were representative of indoor environments. Relevant compounds and compound groups were the wetting agent 2,4,7,9-tetramethyl-5-dicyne-4,7-diol (T4MDD), the plasticiser di-2-ethyl-hexyl-phthalate (DEHP), aliphatic aldehydes, monoterpenes, photoinitiator fragments, acrylic monomers/reactive solvents and diisocyanate monomers. Such substances may affect human health in several ways. Aliphatic aldehydes and some photoinitiator fragments are of strong odour, while acrylates and diisocyanates cause irritation of skin, eyes and upper airways. Terpenes and reactive solvents like styrene undergo indoor chemistry in the presence of ozone, nitrogen oxides or hydroxy radicals. Secondary emission products and reactive species can achieve significant indoor concentrations. On the other hand, it has been reported that even small quantities can cause health effects. In the cases of indoor studies with special regard to emissions from furniture, chemical analysis should always include these compounds.

Salthammer, T.; Schwarz, A.; Fuhrmann, F.

72

Correlations in multiple production in nuclei and the Glauber model for multiple scattering  

SciTech Connect

The Capella-Krzywicki-Shabelskii extension of the Glauber multiple-scattering model to the multiple production of particles in nuclei is applied to the description of correlation phenomena and analyzed critically.

Zoller, V.R.; Nikolayev, N.N.

1982-10-01

73

Multiparticle production in deep inelastic lepton scattering and soft proton proton collisions  

SciTech Connect

We demonstrate how the theoretical knowledge about multiparticle production in deep inelastic lepton scattering can be incorporated into a multistring model for low p/sub t/ proton proton collisions. 25 refs., 8 figs.

Werner, K.

1987-06-01

74

Induced reactive oxygen species improve enzyme production from Aspergillus niger cultivation.  

PubMed

Intracellular reactive oxygen species (iROS) induction by HOCl was used as a novel strategy to improve enzyme productivities in Aspergillus niger growing in a bioreactor. With induced iROS, the specific intracellular activities of alpha-amylase, protease, catalase, and glucose oxidase were increased by about 170%, 250%, 320%, and 260%, respectively. The optimum specific iROS level for achieving maximum cell concentration and enzyme production was about 15 mmol g cell-1. The type of iROS inducing the enzyme production was identified to be a derivative of the superoxide radical. PMID:12882014

Sahoo, Susmita; Rao, K Krishnamurthy; Suraishkumar, G K

2003-05-01

75

Quantum state-resolved reactive scattering of F+H2 in supersonic jets: Nascent HF(v,J) rovibrational distributions via IR laser direct absorption methods  

NASA Astrophysics Data System (ADS)

Supersonically cooled discharge radical atom sources are combined with high-sensitivity IR absorption methods to investigate state-to-state reactive scattering of F+n-H2-->HF(v,J)+H in low-density crossed supersonic jets at center-of-mass collision energies of 2.4(6) kcal/mole. The product HF(v,J) is probed with full vibrational and rotational quantum state selectivity via direct absorption of a single mode (??~0.0001 cm-1), tunable F-center laser in the ?v=1 fundamental manifold with near shot noise limited detection levels of 108 molecules/cm3/quantum state per pulse. The high absorption sensitivity, long mean free path lengths, and low-density conditions in the intersection region permit collision-free HF(v,J) rovibrational product state distributions to be extracted for the first time. Summed over all rotational levels, the HF vibrational branching ratios are 27.0(5)%, 54.2(23)%, 18.8(32)%, and <2(2)%, respectively, into vHF=3:2:1:0. The nascent vibrational distributions are in good agreement with rotationally unresolved crossed-beam studies of Neumark et al. [J. Chem. Phys. 82, 3045 (1985)], as well as with full quantum close-coupled calculations of Castillo and Manolopoulos [J. Chem. Phys. 104, 6531 (1996)] on the lowest adiabatic F+H2 potential surface of Stark and Werner [J. Chem. Phys. 104, 6515 (1996)]. At a finer level of quantum state resolution, the nascent rotational distributions match reasonably well with full quantum theoretical predictions, improving on the level of agreement between theory and experiment from early arrested relaxation studies. Nevertheless, significant discrepancies still exist between the fully quantum state-resolved experiment and theory, especially for the highest energetically allowed rotational levels.

Chapman, William B.; Blackmon, Brad W.; Nizkorodov, Sergey; Nesbitt, David J.

1998-12-01

76

Effect of Brazilian green propolis on the production of reactive oxygen species by stimulated neutrophils  

Microsoft Academic Search

The activity of a crude ethanol extract of green propolis and its fractions obtained by partition with hexane, chloroform and n-butanol was assessed on luminol- and lucigenin- enhanced chemiluminescence (CL) produced by rabbit neutrophils (PMNs) stimulated with particles of serum-opsonized zymosan (OZ). The total production of reactive oxygen species (ROS) by PMNs was measured by the luminol-enhanced CL (LumCL) assay

L. M. C Simões; L. E Gregório; A. A Da Silva Filho; M. L de Souza; A. E. C. S Azzolini; J. K Bastos; Y. M Lucisano-Valim

2004-01-01

77

Inhibition by reactive aldehydes of superoxide anion radical production in stimulated human neutrophils.  

PubMed

alpha,beta-Unsaturated aldehydes were investigated in vitro for their ability to inhibit superoxide anion radical (O2-.) production in stimulated human polymorphonuclear leukocytes (PMN). The aldehydes investigated were (i) trans-4-hydroxynonenal and malonaldehyde (MDA), two toxic lipid peroxidation products; (ii) acrolein and crotonaldehyde, two air pollutants derived from fossil fuel combustion; (iii) trans,trans-muconaldehyde, a putative hematotoxic benzene metabolite. Preincubation of PMN with reactive aldehydes followed by stimulation with the oxygen burst initiator phorbol myristate acetate (PMA) resulted in a dose-dependent inhibition of O2-. production. The concentration at which 50% inhibition (IC50) was observed was 21 microM for acrolein, 23 microM for trans,trans-muconaldehyde, 27 microM for trans-4-hydroxynonenal and 330 microM for crotonaldehyde. A similar inhibitory effect by these aldehydes was observed in digitonin- and concanavalin A-stimulated PMN. MDA inhibited O2-. production in PMA-stimulated PMN by 100% at 10(-2) M but gave no inhibition at 10(-3) M. The standard aldehyde propionaldehyde did not inhibit O2-. production at 10(-3)-10(-6) M. Preincubation of PMN with acrolein in the presence of cysteine completely protected against the inhibitory effect of this reactive aldehyde. The results indicate that the ability of toxic aldehydes to inhibit O2-. production in stimulated PMN correlates directly with their alkylation potential which is a function of the electrophilicity of the beta carbon. PMID:2986857

Witz, G; Lawrie, N J; Amoruso, M A; Goldstein, B D

1985-01-01

78

The Determination and Analysis of Site-Specific Rates of Mitochondrial Reactive Oxygen Species Production  

PubMed Central

Mitochondrial reactive oxygen species (ROS) are widely implicated in physiological and pathological pathways. We propose that it is critical to understand the specific sites of mitochondrial ROS production and their mechanisms of action. Mitochondria possess at least eight distinct sites of ROS production in the electron transport chain and matrix compartment. In this chapter, we describe the nature of the mitochondrial ROS-producing machinery and the relative capacities of each site. We provide detailed methods for the measurement of H2O2 release and the conditions under which maximal rates from each site can be achieved in intact skeletal muscle mitochondria.

Quinlan, Casey L.; Perevoschikova, Irina V.; Goncalves, Renata L.S.; Hey-Mogensen, Martin; Brand, Martin D.

2014-01-01

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

Jet production in muon-proton and muon-nuclei scattering at Fermilab-E665  

Microsoft Academic Search

Measurements of multi-jet production rates from Muon-Proton Muon- Nuclei scattering at Fermilab-E665 are presented. Jet rates are defined by the JADE clustering algorithm. Rates in Muon-Proton deep-inelastic scattering are compared to perturbative Quantum Chromodynamics (PQCD) and Monte Carlo model predictions. We observe hadronic (2+1)-jet rates which are a factor of two higher than PQCD predictions at the partonic level. Preliminary

C. W. Salgado

1993-01-01

81

Deoxyamphimedine, a pyridoacridine alkaloid, damages DNA via the production of reactive oxygen species.  

PubMed

Marine pyridoacridines are a class of aromatic chemicals that share an 11H-pyrido[4,3,2-mn]acridine skeleton. Pyridoacridine alkaloids display diverse biological activities including cytotoxicity, fungicidal and bactericidal properties, production of reactive oxygen species (ROS) and topoisomerase inhibition. These activities are often dependent on slight modifications to the pyridoacridine skeleton. Here we demonstrate that while structurally similar to neoamphimedine and amphimedine, the biological activity of deoxyamphimedine differs greatly. Deoxyamphimedine damages DNA in vitro independent of topoisomerase enzymes through the generation of reactive oxygen species. Its activity was decreased in low oxygen, with the removal of a reducing agent and in the presence of anti-oxidants. Deoxyamphimedine also showed enhanced toxicity in cells sensitive to single or double strand DNA breaks, consistent with the in vitro activity. PMID:19597581

Marshall, Kathryn M; Andjelic, Cynthia D; Tasdemir, Deniz; Concepción, Gisela P; Ireland, Chris M; Barrows, Louis R

2009-01-01

82

Deoxyamphimedine, a Pyridoacridine Alkaloid, Damages DNA via the Production of Reactive Oxygen Species  

PubMed Central

Marine pyridoacridines are a class of aromatic chemicals that share an 11H-pyrido[4,3,2-mn]acridine skeleton. Pyridoacridine alkaloids display diverse biological activities including cytotoxicity, fungicidal and bactericidal properties, production of reactive oxygen species (ROS) and topoisomerase inhibition. These activities are often dependent on slight modifications to the pyridoacridine skeleton. Here we demonstrate that while structurally similar to neoamphimedine and amphimedine, the biological activity of deoxyamphimedine differs greatly. Deoxyamphimedine damages DNA in vitro independent of topoisomerase enzymes through the generation of reactive oxygen species. Its activity was decreased in low oxygen, with the removal of a reducing agent and in the presence of anti-oxidants. Deoxyamphimedine also showed enhanced toxicity in cells sensitive to single or double strand DNA breaks, consistent with the in vitro activity.

Marshall, Kathryn M.; Andjelic, Cynthia D.; Tasdemir, Deniz; Concepcion, Gisela P.; Ireland, Chris M.; Barrows, Louis R.

2009-01-01

83

Reactivation of methionine synthase from Thermotoga maritima (TM0268) requires the downstream gene product TM0269.  

PubMed

The crystal structure of the Thermotoga maritima gene product TM0269, determined as part of genome-wide structural coverage of T. maritima by the Joint Center for Structural Genomics, revealed structural homology with the fourth module of the cobalamin-dependent methionine synthase (MetH) from Escherichia coli, despite the lack of significant sequence homology. The gene specifying TM0269 lies in close proximity to another gene, TM0268, which shows sequence homology with the first three modules of E. coli MetH. The fourth module of E. coli MetH is required for reductive remethylation of the cob(II)alamin form of the cofactor and binds the methyl donor for this reactivation, S-adenosylmethionine (AdoMet). Measurements of the rates of methionine formation in the presence and absence of TM0269 and AdoMet demonstrate that both TM0269 and AdoMet are required for reactivation of the inactive cob(II)alamin form of TM0268. These activity measurements confirm the structure-based assignment of the function of the TM0269 gene product. In the presence of TM0269, AdoMet, and reductants, the measured activity of T. maritima MetH is maximal near 80 degrees C, where the specific activity of the purified protein is approximately 15% of that of E. coli methionine synthase (MetH) at 37 degrees C. Comparisons of the structures and sequences of TM0269 and the reactivation domain of E. coli MetH suggest that AdoMet may be bound somewhat differently by the homologous proteins. However, the conformation of a hairpin that is critical for cobalamin binding in E. coli MetH, which constitutes an essential structural element, is retained in the T. maritima reactivation protein despite striking divergence of the sequences. PMID:17656578

Huang, Sha; Romanchuk, Gail; Pattridge, Katherine; Lesley, Scott A; Wilson, Ian A; Matthews, Rowena G; Ludwig, Martha

2007-08-01

84

Reactivation of methionine synthase from Thermotoga maritima (TM0268) requires the downstream gene product TM0269  

PubMed Central

The crystal structure of the Thermotoga maritima gene product TM0269, determined as part of genome-wide structural coverage of T. maritima by the Joint Center for Structural Genomics, revealed structural homology with the fourth module of the cobalamin-dependent methionine synthase (MetH) from Escherichia coli, despite the lack of significant sequence homology. The gene specifying TM0269 lies in close proximity to another gene, TM0268, which shows sequence homology with the first three modules of E. coli MetH. The fourth module of E. coli MetH is required for reductive remethylation of the cob(II)alamin form of the cofactor and binds the methyl donor for this reactivation, S-adenosylmethionine (AdoMet). Measurements of the rates of methionine formation in the presence and absence of TM0269 and AdoMet demonstrate that both TM0269 and AdoMet are required for reactivation of the inactive cob(II)alamin form of TM0268. These activity measurements confirm the structure-based assignment of the function of the TM0269 gene product. In the presence of TM0269, AdoMet, and reductants, the measured activity of T. maritima MetH is maximal near 80°C, where the specific activity of the purified protein is ?15% of that of E. coli methionine synthase (MetH) at 37°C. Comparisons of the structures and sequences of TM0269 and the reactivation domain of E. coli MetH suggest that AdoMet may be bound somewhat differently by the homologous proteins. However, the conformation of a hairpin that is critical for cobalamin binding in E. coli MetH, which constitutes an essential structural element, is retained in the T. maritima reactivation protein despite striking divergence of the sequences.

Huang, Sha; Romanchuk, Gail; Pattridge, Katherine; Lesley, Scott A.; Wilson, Ian A.; Matthews, Rowena G.; Ludwig, Martha

2007-01-01

85

Design of a reactive distillation process for ultra-low sulfur diesel production  

Microsoft Academic Search

The analysis of the applicability of the reactive separation concepts to the deep-hydrodesulfurization process has been performed. Through the computation of the reactive residue curve maps a basic conceptual design of a reactive distillation column was obtained. This preliminary design considers two reactive zones, each one packed with a different catalyst, a Ni?Mo based catalyst for the bottom reactive section

Eduardo S. Perez-Cisneros; Salvador A. Granados-Aguilar; Pedro Huitzil-Melendez; Tomas Viveros-Garcia

2002-01-01

86

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 160Q22, 0.01xy<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. Jele?; D. Kisielewska; T. Kowalski; E. Rulikowska-Zar?bska; L. Suszycki; J. Zaj?c; A. Kota?ski; M. Przybycie?; I. A. T. Bauerdick; U. Behrens; H. Beier; J. K. Bienlein; C. Coldewey; O. Deppe; K. Desler; G. Drews; M. Flasi?ski; 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. Ma?czak; 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

1995-01-01

87

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

88

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

PubMed Central

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. Images FIGURE 9. FIGURE 10.

Schlosser, M J; Shurina, R D; Kalf, G F

1989-01-01

89

Production of Reactive Oxygen Species from Dissolved Organic Matter Photolysis in Ice  

NASA Astrophysics Data System (ADS)

Dissolved natural organic matter (DOM) is a ubiquitous component of natural waters and an important photosensitizer. A variety of reactive oxygen species (ROS) are known to be produced from DOM photolysis including singlet oxygen, hydroxyl radical, peroxyl radical, etc. Recently, it has been determined that organic material is one of the largest contributors to sunlight absorption in snowpack, however DOM photochemistry in snow/ice has received little attention in the literature. The production of ROS from DOM photolysis in snow/ice could play an important role in snowpack photochemical processes, degradation of pollutants in snowpack, and generation of volatile organic compounds emitted from snowpack. We have investigated ROS production from DOM in frozen aqueous solutions, using commercially available humic and fulvic acids. Here we will discuss the rates of ROS production in both liquid and frozen systems, differences in reactivity amongst the DOM sources studied (Suwannee River Humic Acid, Suwannee River Fulvic Acid, and Pony Lake Fulvic Acid), and the potential implications for snowpack photochemical processes.

Fede, A.; Grannas, A. M.

2012-12-01

90

SUMO1 Negatively Regulates Reactive Oxygen Species Production From NADPH Oxidases  

PubMed Central

Objective Increased protein SUMOylation provides protection from cellular stress including oxidative stress, but the mechanisms involved are incompletely understood. The NADPH oxidases (Nox) are a primary source of reactive oxygen species (ROS) and oxidative stress and thus our goal was to determine whether SUMO regulates NADPH oxidase activity. Methods and Results Increased expression of SUMO1 potently inhibited the activity of Nox1-5. In contrast, inhibition of endogenous SUMOylation with siRNA to SUMO1 or UBC9 or with the inhibitor, anacardic acid, increased ROS production from HEK-Nox5 cells, human vascular smooth muscle cells and neutrophils. The suppression of ROS production was unique to SUMO1, required a C-terminal di-glycine and the SUMO-specific conjugating enzyme, UBC9. SUMO1 did not modify intracellular calcium or Nox5 phosphorylation but reduced ROS output in an isolated enzyme assay suggesting direct effects of SUMOylation on enzyme activity. However, we could not detect the presence of SUMO1-conjugation on Nox5 using a variety of approaches. Moreover the mutation of over 17 predicted and conserved lysine residues on Nox5 did not alter the inhibitory actions of SUMO1. Conclusion Together, these results suggest that SUMO is an important regulatory mechanism that indirectly represses the production of reactive oxygen species to ameliorate cellular stress.

Pandey, D; Chen, F; Patel, A; Wang, CY; Dimitropoulou, C.; Patel, V.S; Rudic, R.D.; Stepp, DW; Fulton, DJR.

2012-01-01

91

Positron production in multiphoton light-by-light scattering  

SciTech Connect

A signal of 106 {+-} 14 positrons above background has been observed in collisions of a low-emittance 46.6-GeV electron beam with terawatt pulses from a Nd:glass laser at 527 nm wavelength in an experiment at the Final Focus Test Beam at SLAC. Peak laser intensities of {approximately} 1.3 {times} 10{sup 18} W/cm{sup 2} have been achieved corresponding to a value of 0.3 for the parameter {Upsilon} = {var_epsilon}*/{var_epsilon}{sub crit} where {var_epsilon}* = 2{gamma}{var_epsilon}{sub lab} is the electric field strength of the laser transformed to the rest frame of the electron beam and {var_epsilon}{sub crit} = m{sup 2}c{sup 3}/e{bar h} = 1.3 {times} 10{sup 16} V/cm is the QED critical field strength. The positrons are interpreted as arising from a two-step process in which laser photons are backscattered to GeV energies by the electron beam followed by a collision between the high-energy photon and several laser photons to produce an electron-positron pair. These results are the first laboratory evidence for a light-by-light scattering process involving only real photons.

Bula, C. [Princeton Univ., NJ (United States). Joseph Henry Labs.; E-144 Collaboration

1997-03-01

92

Proton Compton Scattering and Pion-Production with Polarized Photons  

NASA Astrophysics Data System (ADS)

In analogy to the N-N tensor force in deuteron deformation, a tensor interaction, motivated by one-gluon exchange, between quarks introduces a D state component into the nucleon wave function. The experimental signature of such a quadrupole moment lies in the nucleon's first excited state, the Delta resonance which is photo-excited mainly by M1 photons. However, the D-wave component results in a small E2 transition strength which is quite sensitive to the internal structure of the proton. Since the tensor interaction mixes quark spins with their relative motion, polarization observables can be used to enhance the interference effects that are largely hidden in spin-averaged unpolarized measurements. The p(vec{gamma}, gamma p) and p(vec{gamma }, pi^circ) reactions were studied with linearly polarized gamma -rays between 210 and 330 MeV from the Laser Electron Gamma Source (LEGS) facility at Brookhaven National Laboratory. The two reaction channels were separated by detecting both scattered photons and recoil protons. The beam energy was tagged so that the energy dependent systematic errors were greatly reduced. Data for three sets of center of mass (CM) angle measurements, 60^circ, 90^ circ and 120^circ, are presented in terms of 12 energy bins (+/- 5 MeV). Results are at least in fair agreement comparing with selected model calculations. The measured polarization observables can be used for a new multipole analysis that will serve as a further constraint to the various theoretical models.

Zhang, Hong

1995-01-01

93

Regulation of insulin secretion and reactive oxygen species production by free fatty acids in pancreatic islets.  

PubMed

Free fatty acids regulate insulin secretion through metabolic and intracellular signaling mechanisms such as induction of malonyl-CoA/long-chain CoA pathway, production of lipids, GPRs (G protein-coupled receptors) activation and the modulation of calcium currents. Fatty acids (FA) are also important inducers of ROS (reactive oxygen species) production in ?-cells. Production of ROS for short periods is associated with an increase in GSIS (glucose-stimulated insulin secretion), but excessive or sustained production of ROS is negatively correlated with the insulin secretory process. Several mechanisms for FA modulation of ROS production by pancreatic ?-cells have been proposed, such as the control of mitochondrial complexes and electron transport, induction of uncoupling proteins, NADPH oxidase activation, interaction with the renin-angiotensin system, and modulation of the antioxidant defense system. The major sites of superoxide production within mitochondria derive from complexes I and III. The amphiphilic nature of FA favors their incorporation into mitochondrial membranes, altering the membrane fluidity and facilitating the electron leak. The extra-mitochondrial ROS production induced by FA through the NADPH oxidase complex is also an important source of these species in ?-cells. PMID:21750413

Graciano, Maria Fernanda Rodrigues; Valle, Maíra M R; Kowluru, Anjan; Curi, Rui; Carpinelli, Angelo R

2011-01-01

94

The complex angular momentum (CAM) route to reactive scattering resonances: from a simple model to the F+H2?HF+H reaction  

NASA Astrophysics Data System (ADS)

We advocate the use of the complex angular momentum (CAM) approach for quantitative analysis of the resonance effects in reactive differential and integral cross sections. We start by reviewing a simple potential scattering model and progress to analyse the F+H2(v=0,j=0)?HF(v' =2,j' =0)+H reaction recently considered by Cavalli and De Fazio (2007 Phys. Scr. 76 C21) within the conventional complex energy plane approach. We argue that although the two approaches have the same origin, preference may be given to the CAM method whenever a quantity of interest is obtained by summing a partial wave series.

Sokolovski, D.

2008-10-01

95

Charmonium production in deep inelastic scattering at HERA  

Microsoft Academic Search

. The electroproduction of J\\/# and #(2S) mesons is studied in elastic, quasi-elastic and inclusivereactions for four momentum transfers 2 production is

C. Adlo; V. Andreev; B. Andrieu; V. Arkadov; A. Astvatsatourov; I. Ayyaz; A. Babaev; J. Bahr; P. Baranov; E. Barrelet; W. Bartel; U. Bassler; P. Bate; A. Beglarian; O. Behnke; H.-J. Behrend; C. Beier; A. Belousov; Ch. Berger; G. Bernardi; T. Berndt; G. Bertrand-Coremans; P. Biddulph; J. C. Bizot; V. Boudry; W. Braunschweig; V. Brisson; D. P. Brown; W. Bruckner; P. Bruel; D. Bruncko; J. Burger; F. W. Busser; A. Buniatian; S. Burke; A. Burrage; G. Buschhorn; D. Calvet; A. J. Campbell; T. Carli; E. Chabert; M. Charlet; D. Clarke; B. Clerbaux; J. G. Contreras; C. Cormack; J. A. Coughlan; M.-C. Cousinou; B. E. Cox; G. Cozzika; J. Cvach; J. B. Dainton; W. D. Dau; K. Daum; M. David; M. Davidsson; A. De Roeck; E. A. De Wolf; B. Delcourt; R. Demirchyan; C. Diaconu; M. Dirkmann; P. Dixon; W. Dlugosz; K. T. Donovan; J. D. Dowell; A. Droutskoi; J. Ebert; G. Eckerlin; D. Eckstein; V. Efremenko; S. Egli; R. Eichler; F. Eisele; E. Eisenhandler; E. Elsen; M. Enzenberger; M. Erdmann; A. B. Fahr; P. J. W. Faulkner; L. Favart; A. Fedotov; R. Felst; J. Feltesse; J. Ferencei; F. Ferrarotto; M. Fleischer; G. Flugge; A. Fomenko; J. Formanek; J. M. Foster; G. Franke; E. Gabathuler; K. Gabathuler; F. Gaede; J. Garvey; J. Gassner; J. Gayler; R. Gerhards; S. Ghazaryan; A. Glazov; L. Goerlich; N. Gogitidze; M. Goldberg; I. Gorelov; H. Grassler; T. Greenshaw; G. Grindhammer; T. Hadig; D. Haidt; L. Hajduk; M. Hampel; V. Haustein; W. J. Haynes; B. Heinemann; G. Heinzelmann; R. C. W. Henderson; S. Hengstmann; H. Henschel; R. Heremans; I. Herynek; K. Hewitt; K. H. Hiller; C. D. Hilton; J. Hladky; D. Homann; R. Horisberger; M. Ibbotson; M. Jacquet; M. Jare; L. Janauschek; D. M. Jansen; L. Jonsson; D. P. Johnson; M. Jones; H. Jung; H. K. Kastli; M. Kander; D. Kant; M. Kapichine; M. Karlsson; O. Karschnik; J. Katzy; O. Kaufmann; M. Kausch; N. Keller; I. R. Kenyon; S. Kermiche; C. Keuker; C. Kiesling; M. Klein; C. Kleinwort; G. Knies; J. H. Kohne; H. Kolanoski; S. D. Kolya; V. Korbel; P. Kostka; S. K. Kotelnikov; T. Kramerkamper; M. W. Krasny; H. Krehbiel; D. Kr; K. Kr; A. Kupper; H. Kuster; M. Kuhlen; T. Kurca; W. Lachnit; R. Lahmann; D. Lamb; M. P. J. Landon; W. Lange; U. Langenegger; Duncan Paul Brown

1999-01-01

96

Coherent pion production by neutrino scattering off nuclei  

SciTech Connect

The main part of coherent pion production by neutrinos on nuclei is essentially determined by partial conservation of the axial current (PCAC), provided that the leptonic momentum transferred square Q{sup 2} remains sufficiently small. We give the formulas for the charged and neutral current cross sections, including also the small non-PCAC transverse current contributions and taking into account the effect of the {mu}{sup -}-mass. Our results are compared with the experimental ones and other theoretical treatments.

Kartavtsev, A.; Paschos, E. A.; Gounaris, G. J. [Universitaet Dortmund, Institut fuer Physik, D-44221 Dortmund (Germany); Department of Theoretical Physics, Aristotle University of Thessaloniki, Gr-54124 Thessaloniki (Greece)

2006-09-01

97

Supercritical fluid reactive extraction of Jatropha curcas L. seeds with methanol: A novel biodiesel production method.  

PubMed

The novel biodiesel production technology using supercritical reactive extraction from Jatropha curcas L. oil seeds in this study has a promising role to fill as a more cost-effective processing technology. Compared to traditional biodiesel production method, supercritical reactive extraction can successfully carry out the extraction of oil and subsequent esterification/transesterification process to fatty acid methyl esters (FAME) simultaneously in a relatively short total operating time (45-80 min). Particle size of the seeds (0.5-2.0 mm) and reaction temperature/pressure (200-300 degrees C) are two primary factors being investigated. With 300 degrees C reaction temperature, 240 MPa operating pressure, 10.0 ml/g methanol to solid ratio and 2.5 ml/g of n-hexane to seed ratio, optimum oil extraction efficiency and FAME yield can reach up to 105.3% v/v and 103.5% w/w, respectively which exceeded theoretical yield calculated based on n-hexane Soxhlet extraction of Jatropha oil seeds. PMID:20395131

Lim, Steven; Hoong, Shuit Siew; Teong, Lee Keat; Bhatia, Subhash

2010-09-01

98

Diabetes mellitus increases reactive oxygen species production in the thyroid of male rats.  

PubMed

Diabetes mellitus (DM) disrupts the pituitary-thyroid axis and leads to a higher prevalence of thyroid disease. However, the role of reactive oxygen species in DM thyroid disease pathogenesis is unknown. Dual oxidases (DUOX) is responsible for H(2)O(2) production, which is a cosubstrate for thyroperoxidase, but the accumulation of H(2)O(2) also causes cellular deleterious effects. Nicotinamide adenine dinucleotide phosphate oxidase 4 (NOX4) is another member of the nicotinamide adenine dinucleotide phosphate oxidase family expressed in the thyroid. Therefore, we aimed to evaluate the thyroid DUOX activity and expression in DM rats in addition to NOX4 expression. In the thyroids of the DM rats, we found increased H(2)O(2) generation due to higher DUOX protein content and DUOX1, DUOX2, and NOX4 mRNA expressions. In rat thyroid PCCL3 cells, both TSH and insulin decreased DUOX activity and DUOX1 mRNA levels, an effect partially reversed by protein kinase A inhibition. Most antioxidant enzymes remained unchanged or decreased in the thyroid of DM rats, whereas only glutathione peroxidase 3 was increased. DUOX1 and NOX4 expression and H(2)O(2) production were significantly higher in cells cultivated with high glucose, which was reversed by protein kinase C inhibition. We conclude that thyroid reactive oxygen species is elevated in experimental rat DM, which is a consequence of low-serum TSH and insulin but is also related to hyperglycemia per se. PMID:23407453

Santos, Maria C S; Louzada, Ruy A N; Souza, Elaine C L; Fortunato, Rodrigo S; Vasconcelos, Andressa L; Souza, Kléber L A; Castro, João P S W; Carvalho, Denise P; Ferreira, Andrea C F

2013-03-01

99

Imaging the Proton Via Hard Exclusive Production in Diffractive pp Scattering.  

National Technical Information Service (NTIS)

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 interpl...

C. Weiss C. E. Hyde L. Frankfurt M. Strikman

2007-01-01

100

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

101

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

Microsoft Academic Search

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 pi +, Lambda c + --> pK S 0 and Lambda c + --> Lambda pi +, and their charge conjugates, were reconstructed. The presence of a neutral

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; D. Bartsch; M. Basile; O. Behnke; J. Behr; U. Behrens; L. Bellagamba; A. Bertolin; S. Bhadra; M. Bindi; C. Blohm; T. Bold; E. G. Boos; M. Borodin; 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; F. Dal Corso; J. de Favereau; J. Del Peso; R. K. Dementiev; S. de Pasquale; M. Derrick; R. C. E. Devenish; D. Dobur; B. A. Dolgoshein; 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; Yu. A. Golubkov; P. Göttlicher; I. Grabowska-Bold; J. Grebenyuk; I. Gregor; G. Grigorescu; G. Grzelak; C. Gwenlan; T. Haas; W. Hain; R. Hamatsu; J. C. Hart; H. Hartmann; G. Hartner; E. Hilger; D. Hochman; U. Holm; 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; D. Kollar; P. Kooijman; Ie. 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. Yu. Lukina; P. Luzniak; J. Maeda; S. Magill; I. Makarenko; J. Malka; R. Mankel; A. Margotti; G. Marini; J. F. Martin; A. Mastroberardino; T. Matsumoto; M. C. K. Mattingly; I.-A. Melzer-Pellmann; S. Miglioranzi; F. Mohamad Idris; V. Monaco; A. Montanari; J. D. Morris; 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; Yu. Onishchuk; O. Ota; 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. P Roskuryakov; 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; 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. A. Yagües-Molina; S. Yamada; Y. Yamazaki; R. Yoshida; C. Youngman; A. A. Zarnecki; L. Zawiejski; O. Zenaiev; W. Zeuner; B. O. Zhautykov; N. Zhmak; C. Zhou; A. Zichichi; M. Zolko; D. S. Zotkin; Z. Zulkapli

2010-01-01

102

Domain Product Technique Solution for Scattering by Cylindrical Obstacle in Rectangular Waveguide  

Microsoft Academic Search

The canonical problem of scattering by a cylindrical obstacle in a rectangular waveguide is rigorously reexamined in the framework of the domain product technique. An accurate, rapidly converging algorithm is based on the efficient series representation of the field in a rectangular interaction region. It is shown that the fast convergence of the numerical approximation is stipulated by mathematical properties

Vitaliy P. Chumachenko; Igor V. Petrusenko

2002-01-01

103

Reactive Oxygen Species Production in Peripheral Blood Neutrophils of Obstructive Sleep Apnea Patients  

PubMed Central

Obstructive sleep apnea (OSA) as well as obesity is associated with increased production of reactive oxygen species (ROS). Neutrophils produce great amounts of ROS. The aim was to evaluate peripheral blood neutrophils ROS production in men with OSA and to establish relations with disease severity and obesity. Methods. Forty-six men with OSA and 10 controls were investigated. OSA was confirmed by polysomnography (PSG), when apnea/hypopnea index was >5/h. Body mass index (BMI) was evaluated. Neutrophils were isolated from peripheral blood in the morning after PSG. Dihydrorhodamine-123 was used for ROS detection. Data is presented as median (25th and 75th percentiles). All subjects were divided into four groups: nonobese mild-to-moderate OSA, obese mild-to-moderate OSA, nonobese severe OSA, and obese severe OSA. Results. Neutrophil ROS production was higher in nonobese severe OSA group compared to nonobese mild-to-moderate OSA (mean fluorescence intensity (MFI) 213.4 (89.0–238.9) versus 44.5 (20.5–58.4), P < 0.05). In obese patient groups, ROS production was more increased in severe OSA compared to mild-to-moderate OSA group (MFI 74.5 (47.9–182.4) versus 31.0 (14.8–53.8), P < 0.05). It did not differ in the groups with different BMI and the same severity of OSA. Conclusion. Increased neutrophil ROS production was related to more severe OSA but not obesity.

Miliauskas, Skaidrius; Sakalauskas, Raimundas

2013-01-01

104

[Stimulation of biodecolorization of direct yellow 11 by decolorization products of reactive black 5].  

PubMed

This study focused on the effects of decolorization products of reactive black 5 (RB5) on anaerobic decolorization of direct yellow 11 (DY11) by Rhodopseudomonas palustris W1 and its reaction mechanisms. The results showed that the decolorization products of RB5 could obviously accelerate biological decolorization rate of DY11. For initial concentration of 200 mg/L of DY11, the addition of decolorization products of RB5 resulted in that the decolorization kinetic constant K was increased from 17 mg/(L x h) to 42.5 mg/(L x h), followed by an further increase to 48.8 mg/(L x h) after optimization of RB5 supplement. Cyclic voltammogram analysis demonstrated that the decolorization products of RB5 presented electrochemical activity due to the presence of redox electron transfer mediators, as indicated by an observation of two current peaks of reversible oxidation and reduction appeared at potential of ca. 83 mV and -200 mV, respectively. According to LC-MS and FT-IR analysis, the electrochemically activated species of the decolorization products were characterized to be 7-amino-8-hydroxy-1, 2-naphthaquinone-3, 6-disulphonate-1, 2-diimine (TAHNDSDP-1). TAHNDSDP-1 with quinine-like structure was able to transfer between its oxidative and reductive forms by transferring 2[H], which was supposed to be the redox mediator to shuttle electrons from electron donors to azo dyes, thus, improving the reduction of de materials. PMID:19186827

Wang, Xing-Zu; Cheng, Xiang; Zheng, Hui; Sun, De-Zhi

2008-11-01

105

Spin Biochemistry Modulates Reactive Oxygen Species (ROS) Production by Radio Frequency Magnetic Fields  

PubMed Central

The effects of weak magnetic fields on the biological production of reactive oxygen species (ROS) from intracellular superoxide (O2•?) and extracellular hydrogen peroxide (H2O2) were investigated in vitro with rat pulmonary arterial smooth muscle cells (rPASMC). A decrease in O2•? and an increase in H2O2 concentrations were observed in the presence of a 7 MHz radio frequency (RF) at 10 ?TRMS and static 45 ?T magnetic fields. We propose that O2•? and H2O2 production in some metabolic processes occur through singlet-triplet modulation of semiquinone flavin (FADH•) enzymes and O2•? spin-correlated radical pairs. Spin-radical pair products are modulated by the 7 MHz RF magnetic fields that presumably decouple flavin hyperfine interactions during spin coherence. RF flavin hyperfine decoupling results in an increase of H2O2 singlet state products, which creates cellular oxidative stress and acts as a secondary messenger that affects cellular proliferation. This study demonstrates the interplay between O2•? and H2O2 production when influenced by RF magnetic fields and underscores the subtle effects of low-frequency magnetic fields on oxidative metabolism, ROS signaling, and cellular growth.

Usselman, Robert J.; Hill, Iain; Singel, David J.; Martino, Carlos F.

2014-01-01

106

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

107

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

108

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

109

Measurement of isolated photon production in deep-inelastic scattering at HERA  

Microsoft Academic Search

The production of isolated photons in deep-inelastic scattering ep?e?X is measured with the H1 detector at HERA. The measurement\\u000a is performed in the kinematic range of negative four-momentum transfer squared 422 and a mass of the hadronic system WX>50 GeV. The analysis is based on a total integrated luminosity of 227 pb-1. The production cross section of isolated photons with a transverse

F. D. Aaron; A. Aktas; C. Alexa; V. Andreev; B. Antunovic; S. Aplin; A. Asmone; A. Astvatsatourov; S. Backovic; A. Baghdasaryan; 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; M. Deak; Y. de Boer; B. Delcourt; M. Del Degan; J. Delvax; 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. Falkiewicz; P. J. W. Faulkner; L. Favart; A. Fedotov; R. Felst; J. Feltesse; J. Ferencei; L. Finke; M. Fleischer; A. Fomenko; G. Franke; T. Frisson; E. Gabathuler; J. Gayler; S. Ghazaryan; S. Ginzburgskaya; A. Glazov; I. Glushkov; L. Goerlich; M. Goettlich; N. Gogitidze; S. Gorbounov; M. Gouzevitch; C. Grab; T. Greenshaw; 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; M. Jacquet; M. E. Janssen; 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; 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; G. Li; L. Lindfeld; K. Lipka; A. Liptaj; B. List; J. List; N. Loktionova; R. Lopez-Fernandez; V. Lubimov; A.-I. Lucaci-Timoce; 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; 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; R. Polifka; B. Povh; T. Preda; P. Prideaux; V. Radescu; A. J. Rahmat; N. Raicevic; T. Ravdandorj; P. Reimer; C. Risler; E. Rizvi; P. Robmann; B. Roland; R. Roosen; A. Rostovtsev; Z. Rurikova; S. Rusakov; D. Salek; 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; Z. Staykova; M. Steder; B. Stella; J. Stiewe; U. Straumann; D. Sunar; T. Sykora; V. Tchoulakov; G. Thompson; P. D. Thompson; T. Toll; F. Tomasz; T. H. Tran; D. Traynor; T. N. Trinh; P. Truöl; I. Tsakov; B. Tseepeldorj; G. Tsipolitis; I. Tsurin; J. Turnau; E. Tzamariudaki; K. Urban; D. Utkin; A. Valkárová; C. Vallée; P. Van Mechelen; A. Vargas Trevino; Y. Vazdik; S. Vinokurova; V. Volchinski; G. Weber; R. Weber; D. Wegener; C. Werner; M. Wessels; C. Wissing; R. Wolf; E. Wünsch; S. Xella; V. Yeganov; J. Žá?ek; J. Zálesák; Z. Zhang; A. Zhelezov; A. Zhokin; Y. C. Zhu; T. Zimmermann; H. Zohrabyan; F. Zomer

2008-01-01

110

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

111

Decolorization of an azo dye, Reactive Black 5 and MnP production by yeast isolate: Debaryomyces polymorphus  

Microsoft Academic Search

The optimum conditions for decolorization of an azo dye, C.I. Reactive Black 5 (RB5) and the kinetic characteristics of manganese-dependent peroxidase (MnP) production by yeast isolate, Debaryomyces polymorphus, were investigated. D. polymorphus could completely degrade 200mgl?1 of non-hydrolyzed and hydrolyzed C.I. Reactive Black 5 within 24h of cultivation at an inoculum size of 1.4gl?1 wet cells in 50ml medium consisting

Qingxiang Yang; Ayfer Yediler; Min Yang; Antonius Kettrup

2005-01-01

112

The anti-inflammatory effect of honokiol on neutrophils: mechanisms in the inhibition of reactive oxygen species production  

Microsoft Academic Search

Reactive oxygen species produced by neutrophils contribute to the pathogenesis of focal cerebral ischemia\\/reperfusion injury and signal the inflammatory response. We have previously shown that honokiol, an active principle extracted from Magnolia officinalis, has a protective effect against focal cerebral ischemia\\/reperfusion injury in rats that paralleled a reduction in reactive oxygen species production by neutrophils. To elucidate the underlying mechanism(s)

Kuo-Tong Liou; Yuh-Chiang Shen; Chieh-Fu Chen; Cheng-Ming Tsao; Shen-Kou Tsai

2003-01-01

113

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

114

Ultraendurance exercise increases the production of reactive oxygen species in isolated mitochondria from human skeletal muscle  

PubMed Central

Exercise-induced oxidative stress is important for the muscular adaptation to training but may also cause muscle damage. We hypothesized that prolonged exercise would increase mitochondrial production of reactive oxygen species (ROS) measured in vitro and that this correlates with oxidative damage. Eight male athletes (24–32 yr) performed ultraendurance exercise (kayaking/running/cycling) with an average work intensity of 55% V?o2peak for 24 h. Muscle biopsies were taken from vastus lateralis before exercise, immediately after exercise, and after 28 h of recovery. The production of H2O2 was measured fluorometrically in isolated mitochondria with the Amplex red and peroxidase system. Succinate-supported mitochondrial H2O2 production was significantly increased after exercise (73% higher, P = 0.025) but restored to the initial level at recovery. Plasma level of free fatty acids (FFA) increased fourfold and exceeded 1.2 mmol/l during the last 6 h of exercise. Plasma FFA at the end of exercise was significantly correlated to mitochondrial ROS production (r = 0.74, P < 0.05). Mitochondrial content of 4-hydroxy-nonenal-adducts (a marker of oxidative damage) was increased only after recovery and was not correlated with mitochondrial ROS production. Total thiol group level and glutathione peroxidase activity were elevated after recovery. In conclusion, ultraendurance exercise increases ROS production in isolated mitochondria, but this is reversed after 28 h recovery. Mitochondrial ROS production was not correlated with oxidative damage of mitochondrial proteins, which was increased at recovery but not immediately after exercise.

Shabalina, Irina G.; Mattsson, C. Mikael; Bakkman, Linda; Fernstrom, Maria; Rozhdestvenskaya, Zinaida; Enqvist, Jonas K.; Nedergaard, Jan; Ekblom, Bjorn; Tonkonogi, Michail

2010-01-01

115

Mouse Melanoma Cell Migration is Dependent on Production of Reactive Oxygen Species under Normoxia Condition  

PubMed Central

Cell migration plays a role in many physiological and pathological processes. Reactive oxygen species (ROS) produced in mammalian cells influence intracellular signaling processes which in turn regulate various biological activities. Here, we investigated whether melanoma cell migration could be controlled by ROS production under normoxia condition. Cell migration was measured by wound healing assay after scratching confluent monolayer of B16F10 mouse melanoma cells. Cell migration was enhanced over 12 h after scratching cells. In addition, we found that ROS production was increased by scratching cells. ERK phosphorylation was also increased by scratching cells but it was decreased by the treatment with ROS scavengers, N-acetylcysteine (NAC). Tumor cell migration was inhibited by the treatment with PD98059, ERK inhibitor, NAC or DPI, well-known ROS scavengers. Tumor cell growth as judged by succinate dehydrogenase activity was inhibited by NAC treatment. When mice were intraperitoneally administered with NAC, the intracellular ROS production was reduced in peripheral blood mononuclear cells. In addition, B16F10 tumor growth was significantly inhibited by in vivo treatment with NAC. Collectively, these findings suggest that tumor cell migration and growth could be controlled by ROS production and its downstream signaling pathways, in vitro and in vivo.

Im, Yun-Sun; Ryu, Yun-Kyoung; Moon, Eun-Yi

2012-01-01

116

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

117

Entropy production in multiple scattering of light by a spatially random medium  

NASA Astrophysics Data System (ADS)

This study reports on the problem of entropy production due to multiple scattering of light by a spatially random medium composed of uncorrelated and noninteracting spherical dielectric particles. The degree of polarization P of light, in the form of plane waves, is of the nature of an order parameter for the ensemble of realizations of the fluctuating optical field. The radiation entropy takes a form analogous to the entropy of one-dimensional Ising (two-level) spin systems in contact with a heat bath. On the basis of this analysis, the degree of polarization has a different thermodynamic significance. It is argued that within this representation, one may define an effective polarization temperature ? we then show how ? depends on the degree of polarization. Light transmitted through a multiple scattering medium is depolarized by decorrelation of the phases of the electric field components and its polarization entropy increases. The effects of size of the spherical particles and of the optical depth on entropy production are studied numerically, using the Mie theory, via the Monte Carlo method. An attempt is made to interpret these results in terms of the minimization procedure (minimum entropy production) that plays a fundamental role in classical irreversible thermodynamics. One of the most remarkable aspects of this problem, where no energy exchange between radiation and scatterer takes place, is that the stationary state corresponds both to the state of minimum production of radiation entropy and to the state of maximum entropy. Thermodynamically, multiple scattering can be viewed as an order-disorder transition using the spin model. It is also emphasized that the system will tend to evolve towards a ``higher polarization temperature'' state. We briefly comment on the use of our treatment in interpreting the irreversibility in a scattering process.

Brosseau, Christian; Bicout, Dominique

1994-12-01

118

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

119

Role of reactive oxygen species in LPS-induced production of prostaglandin E2 in microglia.  

PubMed

We determined the roles of reactive oxygen species (ROS) in the expression of cyclooxygenase-2 (COX-2) and the production of prostaglandin E2 (PGE2) in lipopolysaccharide (LPS)-activated microglia. LPS treatment increased intracellular ROS in rat microglia dose-dependently. Pre-treatment with superoxide dismutase (SOD)/catalase, or SOD/catalase mimetics that can scavenge intracellular ROS, significantly attenuated LPS-induced release in PGE2. Diphenylene iodonium (DPI), a non-specific NADPH oxidase inhibitor, decreased LPS-induced PGE2 production. In addition, microglia from NADPH oxidase-deficient mice produced less PGE2 than those from wild-type mice following LPS treatment. Furthermore, LPS-stimulated expression of COX-2 (determined by RT-PCR analysis of COX-2 mRNA and western blot for its protein) was significantly reduced by pre-treatment with SOD/catalase or SOD/catalase mimetics. SOD/catalase mimetics were more potent than SOD/catalase in reducing COX-2 expression and PGE2 production. As a comparison, scavenging ROS had no effect on LPS-induced nitric oxide production in microglia. These results suggest that ROS play a regulatory role in the expression of COX-2 and the subsequent production of PGE2 during the activation process of microglia. Thus, inhibiting NADPH oxidase activity and subsequent ROS generation in microglia can reduce COX-2 expression and PGE2 production. These findings suggest a potential therapeutic intervention strategy for the treatment of inflammation-mediated neurodegenerative diseases. PMID:14756815

Wang, Tongguang; Qin, Liya; Liu, Bin; Liu, Yuxin; Wilson, Belinda; Eling, Thomas E; Langenbach, Robert; Taniura, Seijiro; Hong, Jau-Shyong

2004-02-01

120

Effects of Hepatitis C core protein on mitochondrial electron transport and production of reactive oxygen species  

PubMed Central

Viral infections frequently alter mitochondrial function with suppression or induction of apoptosis and enhanced generation of reactive oxygen species. The mechanisms of these effects are varied and mitochondria are affected by both direct interactions with viral proteins as well as by secondary effects of viral activated signaling cascades. This chapter describes methods used in our laboratory to assess the effects of the Hepatitis C virus core protein on mitochondrial ROS production, electron transport and Ca2+ uptake. These include measurements of the effects of in vitro incubation of liver mitochondria with purified core protein as well as assessment of the function of mitochondria in cells and tissues expressing core and other viral proteins. These methods are generally applicable to the study of viral-mitochondrial interactions.

Campbell, Roosevelt V.; Yang, Yuanzheng; Wang, Ting; Rachamallu, Aparna; Li, Yanchun; Watowich, Stanley J.; Weinman, Steven A.

2014-01-01

121

Electron-beam stimulation of the reactivity of cellulose pulps for production of derivatives  

NASA Astrophysics Data System (ADS)

New alternative technologies for manufacture of cellulose fibers are currently under development. The effect of electron beam irradiation on various types of cellulose pulps have been studied in order to improve the reactivity of raw material for production of cellulose derivatives. Three different types of textile pulps, Alicell (Canada), Borregaard (Norwegian), Ketchikan (USA) and Kraft softwood as well as Kraft hardwood pulps, have been irradiated with 10 MeV electron beam from LAE 13/g linear accelerator with dose 10, 15, 20, 25 and 50 kGy. Electron paramagnetic resonance spectroscopy (ESR) and gel permeation chromatography (GPC) were applied for determination of structural changes in irradiated pulps. Such parameters as viscosity, average degree of polymerization and ?-cellulose contents were determinated by means of analytical methods. Results of there investigations are presented and discussed.

Iller, Edward; Kukie?ka, Aleksandra; Stupi?ska, Halina; Miko?ajczyk, W?odzimierz

2002-03-01

122

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

NASA Astrophysics Data System (ADS)

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.

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

1995-03-01

123

Reactive-Environment Hollow Cathode Sputtering: Compound Film Production, and Application to Thin Film Photovoltaics  

Microsoft Academic Search

This paper reviews EPV's development of hardware and process technology to accomplish large area, high rate sputtering from metal targets in a reactive mode without target poisoning. The method is termed reactive-environment hollow cathode sputtering (RE-HCS) and makes use of the intense plasma confined in a hollow cathode. A linearly extended cathode is described, with one or more reactive gases

Alan E. Delahoy; Sheyu Guo; John Cambridge; Rob Lyndall; J. A. A. Selvan; Anamika Patel; A. Foustotchenko; Baosheng Sang

2006-01-01

124

VASECTOMY REVERSAL ASSOCIATED WITH INCREASED REACTIVE OXYGEN SPECIES PRODUCTION BY SEMINAL FLUID LEUKOCYTES AND SPERM  

Microsoft Academic Search

PurposeReactive oxygen species, which are primarily produced by leukocytes, are generally detrimental to sperm. High reactive oxygen species levels are found in men with abnormal sperm function. Since men often have poor sperm characteristics and infertility after vasectomy reversal, fertile men to determine if reactive oxygen species were elevated in the former group.

ROBERT H. SHAPIRO; CHARLES H. MULLER; GREGORY CHEN; RICHARD E. BERGER

1998-01-01

125

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

126

Butein suppresses breast cancer growth by reducing a production of intracellular reactive oxygen species  

PubMed Central

Background Butein has various functions in human diseases including cancer. While anti-cancer effects of butein have been revealed, it is urgent to understand a unique role of butein against cancer. In this study, we demonstrate that butein inhibition of reactive oxygen species (ROS) production results in suppression of breast cancer growth. Methods Different breast cancer cell lines were treated with butein and then subjected to cell viability and apoptosis assays. Butein-sensitive or -resistant breast cancer cells were injected into mammary fat pads of immunocompromised mice and then butein was injected. Breast cancer cells were categorized on the basis of butein sensitivity. Results Butein reduced viabilities of different breast cancer cells, while not affecting those of HER2-positive (HER2+) HCC-1419, SKBR-3 and HCC-2218 breast cancer cells. Butein reduction of ROS levels was correlated with apoptotic cell death. Furthermore, butein reduction of ROS level led to inhibitions of AKT phosphorylation. N-acetyl-L-cysteine (NAC), a free radical scavenger, also reduced ROS production and AKT phosphorylation, resulting in apoptotic cell death. In contrast, inhibitory effects of both butein and NAC on ROS production and AKT phosphorylation were not detected in butein-resistant HER2+ HCC-1419, SKBR-3 and HCC-2218 cells. In the in vivo tumor growth assays, butein inhibited tumor growth of butein-sensitive HER2+ BT-474 cells, while not affecting that of butein-resistant HER2+ HCC-1419 cells. Moreover, butein inhibition of ROS production and AKT phosphorylation was confirmed by in vivo tumor growth assays. Conclusions Our study first reveals that butein causes breast cancer cell death by the reduction of ROS production. Therefore, our finding provides better knowledge for butein effect on breast cancer and also suggests its treatment option.

2014-01-01

127

Measurement of internal jet structure in dijet production in deep-inelastic scattering at HERA  

Microsoft Academic Search

Internal jet structure in dijet production in deep-inelastic scattering is measured with the H1 detector at HERA. Jets with transverse energies ET,Breit > 5 GeV are selected in the Breit frame employing k? and cone jet algorithms. In the kinematic region of ssquared momentum transfers 10 < Q2 ?s 120 GeV2 and Bjorken?x values 2 < 10?4 ? xBj ?

C. Adloff; V. Andreev; B. Andrieu; V. Arkadov; A. Astvatsatourov; I. Ayyaz; A. Babaev; J. Bähr; P. Baranov; E. Barrelet; W. Bartel; U. Bassler; P. Bate; A. Beglarian; O. Behnke; H.-J. Behrend; C. Beier; A. Belousov; Ch. Berger; G. Bernardi; T. Berndt; G. Bertrand-Coremans; P. Biddulph; J. C. Bizot; V. Boudry; W. Braunschweig; V. Brisson; D. P. Brown; W. Brückner; P. Bruel; D. Bruncko; J. Bürger; F. W. Büsser; A. Buniatian; S. Burke; G. Buschhorn; D. Calvet; A. J. Campbell; T. Carli; E. Chabert; M. Charlet; D. Clarke; B. Clerbaux; S. Cocks; J. G. Contreras; C. Cormack; J. A. Coughlan; M.-C. Cousinou; B. E. Cox; G. Cozzika; J. Cvach; J. B. Dainton; W. D. Dau; K. Daum; M. David; M. Davidsson; A. De Roeck; E. A. De Wolf; B. Delcourt; R. Demirchyan; C. Diaconu; M. Dirkmann; P. Dixon; W. Dlugosz; K. T. Donovan; J. D. Dowell; A. Droutskoi; J. Ebert; G. Eckerlin; D. Eckstein; V. Efremenko; S. Egli; R. Eichler; F. Eisele; E. Eisenhandler; M. Enzenberger; A. B. Farh; L. Favart; A. Fedotov; R. Felst; J. Feltesse; F. Ferrarotto; M. Fleischer; G. Flügge; A. Fomenko; J. Formánek; G. Franke; E. Gabathuler; K. Gabathuler; F. Gaede; J. Garvey; J. Gassner; R. Gerhards; S. Ghazaryan; A. Glazov; L. Goerlich; N. Gogitidze; M. Goldberg; I. Gorelov; C. Grab; H. Grässler; T. Greenshaw; R. K. Griffiths; G. Grindhammer; T. Hadig; D. Haidt; L. Hajduk; M. Hampel; V. Haustein; W. J. Haynes; B. Heinemann; G. Heinzelmann; R. C. W. Henderson; S. Hengstmann; H. Henschel; R. Heremans; I. Herynek; K. Hewitt; K. H. Hiller; C. D. Hilton; J. Hladký; D. Hoffmann; T. Holtom; R. Horisberger; S. Hurling; M. Ibbotson; Ç. ??sever; M. Jacquet; D. M. Jansen; L. Jönsson; D. P. Johnson; H. Jung; H. K. Kästli; M. Kander; D. Kant; M. Kapichine; O. Karschnik; J. Katzy; O. Kaufmann; M. Kausch; N. Keller; I. R. Kenyon; S. Kermiche; C. Keuker; C. Kiesling; M. Klein; C. Kleinwort; G. Knies; J. H. Köhne; H. Kolanoski; S. D. Kolya; V. Korbel; P. Kostka; S. K. Kotelnikov; T. Krämerkämper; M. W. Krasny; H. Krehbiel; D. Krücker; K. Krüger; A. Küpper; H. Küster; M. Kuhlen; T. Kur?a; W. Lachnit; R. Lahmann; D. Lamb; M. P. J. Landon; W. Lange; U. Langenegger; A. Lebedev; F. Lehner; V. Lemaitre; R. Lemrani; V. Lendermann; S. Levonian; M. Lindstroem; G. Lobo; E. Lobodzinska; V. Lubimov; S. Lüders; D. Lüke; L. Lytkin; N. Magnussen; H. Mahlke-Krüger; N. Malden; E. Malinovsky; I. Malinovski; R. Mara?ek; P. Marage; J. Marks; R. Marshall; H.-U. Martyn; J. Martyniak; S. J. Maxfield; S. J. McMahon; T. R. McMahon; A. Mehta; K. Meier; P. Merkel; F. Metlica; A. Meyer; H. Meyer; J. Meyer; P.-O. Meyer; S. Mikocki; D. Milstead; R. Mohr; S. Mohrdieck; M. Mondragon; F. Moreau; A. Morozov; J. V. Morris; D. Müller; K. Müller; P. Murín; V. Nagovizin; B. Naroska; J. Naumann; Th. Naumann; I. Négri; P. R. Newman; H. K. Nguyen; T. C. Nicholls; F. Niebergall; C. Niebuhr; Ch. Niedzballa; H. Niggli; O. Nix; G. Nowak; T. Nunnemann; H. Oberlack; J. E. Olsson; D. Ozerov; P. Palmen; V. Panassik; C. Pascaud; S. Passaggio; G. D. Patel; H. Pawletta; E. Perez; J. P. Phillips; A. Pieuchot; D. Pitzl; R. Pöschl; G. Pope; B. Povh; K. Rabbertz; J. Rauschenberger; P. Reimer; B. Reisert; D. Reyna; H. Rick; S. Riess; E. Rizvi; P. Robmann; R. Roosen; K. Rosenbauer; A. Rostovtsev; F. Rouse; C. Royon; S. Rusakov; K. Rybicki; D. P. C. Sankey; P. Schacht; J. Scheins; F.-P. Schilling; S. Schleif; P. Schleper; D. Schmidt; L. Schoeffel; V. Schröder; H.-C. Schultz-Coulon; F. Sefkow; A. Semenov; V. Shekelyan; I. Sheviakov; L. N. Shtarkov; G. Siegmon; Y. Sirois; T. Sloan; P. Smirnov; M. Smith; V. Solochenko; Y. Soloviev; L. Sonnenschein; V. Spaskov; A. Specka; H. Spitzer; F. Squinabol; R. Stamen; P. Steffen; R. Steinberg; J. Steinhart; B. Stella; A. Stellberger; J. Stiewe; U. Straumann; W. Struczinski; J. P. Sutton; M. Swart; S. Tapprogge; M. Taševský; V. Tchernyshov; S. Tchetchelnitski; J. Theissen; G. Thompson; P. D. Thompson; N. Tobien; R. Todenhagen; D. Traynor; P. Truöl; G. Tsipolitis; J. Turnau; E. Tzamariudaki; S. Udluft; A. Usik; S. Valkár; A. Valkárová; C. Vallée; P. Van Esch; A. Van Haecke; P. Van Mechelen; Y. Vazdik; G. Villet; K. Wacker; R. Wallny; T. Walter; B. Waugh; G. Weber; M. Weber; D. Wegener; A. Wegner; T. Wengler; M. Werner; L. R. West; S. Wiesand; T. Wilksen; S. Willard; M. Winde; G.-G. Winter; Ch. Wissing; C. Wittek; E. Wittmann; M. Wobisch; H. Wollatz; E. Wünsch; J. Žá?ek; J. Zálešák; Z. Zhang; A. Zhokin; P. Zini; F. Zomer; J. Zsembery; M. zur Nedden

1999-01-01

128

First measurement of Z\\/? ? production in Compton scattering of quasi-real photons  

Microsoft Academic Search

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 55pb?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

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

1998-01-01

129

Observation of jet production in deep inelastic scattering with a large rapidity gap at HERA  

Microsoft Academic Search

Events with a large rapidity gap in deep inelastic scattering with Q2 >= 10 GeV2 have been studied in the ZEUS detector. The properties of these events with W > 140 GeV are consistent with a leading twist diffractive production mechanism. In the laboratory frame, with ETjet >= 4 GeV, 15% of the events are of the 1-jet type with

M. Derrick; D. Krakauer; S. Magill; B. Musgrave; J. Repond; J. Schlereth; R. Stanek; R. L. Talaga; J. Thron; F. Arzarello; R. Ayad; 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; F. Ciralli; A. Contin; S. D'Auria; C. del Papa; F. Frasconi; P. Giusti; G. Iacobucci; G. Laurenti; G. Levi; G. Maccarrone; A. Margotti; T. Massam; R. Nania; C. Nemoz; F. Palmonari; G. Sartorelli; R. Timellini; Y. Zamora Garcia; A. Zichichi; A. Bargende; J. Crittenden; K. Desch; B. Diekmann; T. Doeker; L. Feld; A. Frey; M. Geerts; G. Geitz; H. Hartmann; D. Haun; K. Heinloth; E. Hilger; H.-P. Jakob; U. F. Katz; S. Kramarczyk; A. Mass; S. Mengel; J. Mollen; E. Paul; Ch. Rembser; R. Schattevoy; J.-L. Schneider; 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. J. Tapper; S. S. Wilson; R. Yoshida; R. R. Rau; M. Arneodo; M. Schioppa; G. Susinno; A. Bernstein; A. Caldwell; I. Gialas; J. A. Parsons; S. Ritz; F. Sciulli; P. B. Straub; L. Wai; S. Yang; 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. Zajc; T. Kedzierski; A. Kotanski; M. Przybycien; L. A. T. Bauerdick; U. Behrens; J. K. Bienlein; S. Böttcher; C. Coldewey; G. Drews; M. Flasinski; I. Fleck; D. J. Gilkinson; P. Göttlicher; B. Gutjahr; T. Haas; L. Hagge; W. Hain; D. Hassell; H. Heßling; H. Hultschig; P. Joos; M. Kasemann; R. Klanner; W. Koch; L. Köpke; U. Kötz; H. Kowalski; W. Kröger; J. Krüger; J. Labs; A. Ladage; B. Löhr; M. Löwe; D. Lüke; J. Mainusch; O. Manczak; J. S. T. Ng; S. Nickel; D. Notz; K. Ohrenberg; M. Rohde; J. Roldán; U. Schneekloth; J. Schroeder; W. Schulz; F. Selonke; E. Stiliaris; T. Tsurugai; W. Vogel; D. Westphal; G. Wolf; C. Youngman; H. J. Grabosch; J. Leich; A. Meyer; C. Rethfeldt; S. Schlenstedt; G. Barbagli; M. Nuti; P. Pelfer; G. Anzivino; S. de Pasquale; S. Qian; L. Votano; A. Bamberger; A. Freidhof; T. Poser; S. Söldner-Rembold; G. Theisen; T. Trefzger; N. H. Brook; P. J. Bussey; A. T. Doyle; J. R. Forbes; V. A. Jamieson; C. Raine; D. H. Saxon; M. Stavrianakou; A. S. Wilson; A. Dannemann; U. Holm; D. Horstmann; H. Kammerlocher; B. Krebs; T. Neumann; R. Sinkus; K. Wick; E. Badura; B. D. Burow; A. Fürtjes; E. Lohrmann; J. Milewski; M. Nakahata; N. Pavel; G. Poelz; W. Schott; J. Terron; F. Zetsche; T. C. Bacon; R. Beuselinck; I. Butterworth; E. Gallo; V. L. Harris; K. R. Long; D. B. Miller; P. Morawitz; A. Prinias; J. K. Sedgbeer; A. Vorvolakos; A. Whitfield; T. Bienz; H. Kreutzmann; U. Mallik; E. McCliment; M. Roco; M. Z. Wang; P. Cloth; D. Filges; S. H. An; S. M. Hong; C. O. Kim; T. Y. Kim; 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. F. de Trocóniz; F. Ikraiam; J. K. Mayer; G. R. Smith; F. Corriveau; D. S. Hanna; J. Hartmann; L. W. Hung; J. N. Lim; C. G. Matthews; J. W. Mitchell; P. M. Patel; L. E. Sinclair; D. G. Stairs; M. St. Laurent; R. Ullmann; 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; E. N. Kuznetsov; A. A. Savin; A. N. Solomin; A. G. Voronin; N. P. Zotov; S. Bentvelsen; M. Botje; F. Chlebana; A. Dake; J. Engelen; P. de Jong; M. de Kamps; P. Kooijman; A. Kruse; V. O'dell; A. Tenner; 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; J. McFall; C. Nath; 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; F. Gasparini; 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; M. Guida; M. Iori; S. M. Mari; G. Marini; M. Mattioli; A. Nigro; J. C. Hart; N. A. McCubbin; K. Prytz; T. P. Shah; T. L. Short; E. Barberis; N. Cartiglia; C. Heusch; M. van Hook; B. Hubbard; W. Lockman; H. F.-W. Sadrozinski; A. Seiden; D. Zer-Zion; J. Biltzinger; R. J. Seifert; A. H. Walenta; G. Zech; H. Abramowicz; S. Dagan; A. Levy; T. Hasegawa; M. Hazumi; T. Ishii; M. Kuze; S. Mine; Y. Nagasawa; T. Nagira; M. Nakao; I. Suzuki; K. Tokushuku

1994-01-01

130

Exclusive ? 0 production in deep inelastic electron-proton scattering at HERA  

Microsoft Academic Search

The exclusive production of ?0 mesons in deep inelastic electron-proton scattering has been studied using the ZEUS detector. Cross sections have been measured in the range 7 < Q2 < 25 GeV2 for ??p centre of mass (c.m.) energies 40 to 130 GeV. The ??p ? ?0p cross section exhibits a Q?(4.2±0.8?0.5+1.4) dependence and both longitudinally and transversely polarised ?0's

S. Bhadra; M. L. Cardy; C.-P. Fagerstroem; W. R. Frisken; K. M. Furutani; M. Khakzad; W. B. Schmidke; R. L. Talaga; H. Zhang; R. Ayad; G. Bari; M. Basile; L. Bellagamba; D. Boscherini; A. Bruni; G. Bruni; P. Bruni; G. Cara Romeo; G. Castellini; M. Chiarini; Luisa Cifarelli; F. Cindolo; A. Contin; M. Corradi; I. Gialas; P. Giusti; G. Iacobucci; G. Laurenti; G. Levi; A. Margotti; Thomas Massam; R. Nania; C. Nemoz; F. Palmonari; A. Polini; G. Sartorelli; R. Timellini; Y. Zamora Garcia; Antonino Zichichi; A. Bargende; James Arthur Crittenden; Klaus Desch; B. Diekmann; T. Doeker; M. Eckert; L. Feld; A. Frey; M. Geerts; M. Grothe; H. Hartmann; K. Heinloth; E. Hilger; H.-P. Jakob; U. F. Katz; S. M. Mari; S. Mengel; J. Mollen; E. Paul; M. Pfeiffer; Ch. Rembser; 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. J. Tapper; S. S. Wilson; R. Yoshida; R. R. Rau; M. Arneodo; M. Capua; A. Garfagnini; L. Iannotti; M. Schioppa; G. Susinno; A M Bernstein; A. Caldwell; N. Cartiglia; J. A. Parsons; S. Ritz; F. Sciulli; P. B. Straub; L. Wai; S. Yang; Q. Zhu; P. Borzemski; J. Chwastowski; Andrzej Eskreys; K. Piotrzkowski; M. Zachara; L. Zawiejski; L. Adamczyk; B. Bednarek; K. Jelen; D. Kisielewska; T. Kowalski; E. Rulikowska-Zarebska; L. Suszycki; J. Zajac; Andrzej Kotanski; M B Przybycien; L. 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; T. Haas; W. Hain; D. Hasell; H Hessling; Y. Iga; K. Johnson; P. Joos; M. Kasemann; Robert Klanner; W. Koch; L. Köpke; U. Kötz; H. Kowalski; J. Labs; A. Ladage; B. Löhr; M Loewe; D. Lüke; J. Mainusch; O. Manczak; T. Monteiro; J. S. T. Ng; S. Nickel; D. Notz; K. Ohrenberg; M T Roco; M. Rohde; J. Roldán; U. Schneekloth; W. Schulz; F. Selonke; E. Stiliaris; B. Surrow; T Voss; D. Westphal; G. Wolf; C. Youngman; W. Zeuner; J. F. Zhou; H. J. Grabosch; A I Kharchilava; A. Leich; M. C. K. Mattingly; A. Meyer; S. Schlenstedt; N. Wulff; G. Barbagli; P G Pelfer; Giuseppina Anzivino; G D Maccarrone; S. de Pasquale; L. Votano; Andreas Bamberger; S. Eisenhardt; A. Freidhof; S. Söldner-Rembold; J. Schroeder; T M Trefzger; N. H. Brook; Peter J Bussey; A. T. Doyle; J. 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. Milewski; M. Nakahata; N. Pavel; G. Poelz; W. Schott; F. Zetsche; Trevor C Bacon; N. Bruemmer; Ian Butterworth; E. Gallo; V. L. Harris; B. H. Y. 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; 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; J. P. Fernandez; R. Graciani; J. M. Hernández; L. Hervás; L. Labarga; M. Martinez; 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 T Ullmann; G. Zacek; V. Bashkirov; B. A. Dolgoshein; A. Stifutkin; G. L. Bashindzhagyan; P. F. Ermolov; L. K. Gladilin; Yu. A. Golubkov; V. D. Kobrin; I. A. Korzhavina; V. A. Kuzmin; O. Yu. Lukina; A. S. Proskuryakov; A. A. Savin; L. M. Shcheglova; A. N. Solomin; N. P. Zotov; M. Botje; F S Chlebana; A P Dake; J. Engelen; M. de Kamps; P M Kooijman; A. Kruse; H G Tiecke; W. Verkerke; M. Vreeswijk; L. Wiggers; E. de Wolf; R. van Woudenberg; D. Acosta; B G Bylsma; L. S. Durkin; K. Honscheid; Li Chuan; T. Y. Ling; K. W. McLean; W. N. Murray; I. H. Park; T. A. Romanowski; R. Seidlein; D. S. Bailey; A. Byrne; R. J. Cashmore; A. M. Cooper-Sarkar; R. C. E. Devenish; N. Harnew; M. Lancaster; L. Lindemann; J. D. McFall; C. Nath; V. A. Noyes; A. Quadt; J. R. Tickner; H. Uijterwaal; R. Walczak; D. S. Waters; 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; E. Barberis; T. Dubbs; C. Heusch; M. van Hook; W. Lockman; J. T. Rahn; H. F.-W. Sadrozinski; A. Seiden; D. C. Williams; J. Biltzinger; R. J. Seifert; O. Schwarzer; 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

1995-01-01

131

DETERMINATION OF ANDROGRAPHOLIDE IN COMMERCIAL ANDROGRAPHIS (ANDROGRAPHIS PANICULATA) PRODUCTS USING HPLC WITH EVAPORATIVE LIGHT SCATTERING DETECTION  

Microsoft Academic Search

A reverse-phase high performance liquid chromatographic method is developed for the determination of andrographolide, a characteristic diterpene lactone in commercial Andrographis (Andrographis paniculata) products. Samples are analyzed by means of a reverse-phase column (Supelco Discovery C18) using acetonitrile and water, under gradient conditions as the mobile phase, over 40?min. The evaporative light scattering detector (ELSD) used, was set at an

Wenkui Li; John F. Fitzloff

2002-01-01

132

Reactive oxygen species and IRF1 stimulate IFN? production by proximal tubules during ischemic AKI  

PubMed Central

We previously reported that expression of the transcription factor interferon regulatory factor 1 (IRF1) is an early, critical maladaptive signal expressed by renal tubules during murine ischemic acute kidney injury (AKI). We now show that IRF1 mediates signals from reactive oxygen species (ROS) generated during ischemic AKI and that these signals ultimately result in production of ?-subtypes of type I interferons (IFN?s). We found that genetic knockout of the common type I IFN receptor (IFNARI?/?) improved kidney function and histology during AKI. There are major differences in the spatial-temporal production of the two major IFN subtypes, IFN? and IFN?s: IFN? expression peaks at 4 h, earlier than IFN?s, and continues at the same level at 24 h; expression of IFN?s also increases at 4 h but continues to increase through 24 h. The magnitude of the increase in IFN?s relative to baseline is much greater than that of IFN?. We show by immunohistology and study of isolated cells that IFN? is produced by renal leukocytes and IFN?s are produced by renal tubules. IRF1, IFN?s, and IFNARI were found on the same renal tubules during ischemic AKI. Furthermore, we found that ROS induced IFN? expression by renal tubules in vitro. This expression was inhibited by small interfering RNA knockdown of IRF1. Overexpression of IRF1 resulted in the production of IFN?s. Furthermore, we found that IFN? stimulated production of maladaptive proinflammatory CXCL2 by renal tubular cells. Altogether our data support the following autocrine pathway in renal tubular cells: ROS > IRF1 > IFN? > IFNARI > CXCL2.

Winterberg, Pamela D.; Wang, Yanxia; Lin, Keng-Mean; Hartono, John R.; Nagami, Glenn T.; Zhou, Xin J.; Shelton, John M.; Richardson, James A.

2013-01-01

133

Semiclassical study of reactive scattering in a laser field - F + H2 + barred-h times omega times /1.06 microns/ system  

NASA Technical Reports Server (NTRS)

Semiclassical calculations of collinear F+H2(nu = 0) reactive and inelastic scattering in an Nd-glass laser field of various intensities are described. The decoupling approximation developed for the Miller-George theory is used for nonadiabatic transitions between the electronic-field surfaces, and special attention is paid to the choice of a proper coordinate system for applying the decoupling approximation. An increase in the total reaction probability and population ratio of the nu = 3 over nu = 2 vibrational state of HF occurs suddenly as the field intensity increases beyond 10 TW/sq cm. It is found that in a laser field the H2 molecule can be vibrationally excited while the F atom is electronically excited.

Yuan, J.-M.; George, T. F.

1979-01-01

134

Conversion of Natively Unstructured ?-Synuclein to Its ?-Helical Conformation Significantly Attenuates Production of Reactive Oxygen Species  

PubMed Central

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 H2O2 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.

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

2012-01-01

135

Insulin Regulates Glucose Consumption and Lactate Production through Reactive Oxygen Species and Pyruvate Kinase M2  

PubMed Central

Although insulin is known to regulate glucose metabolism and closely associate with liver cancer, the molecular mechanisms still remain to be elucidated. In this study, we attempt to understand the mechanism of insulin in promotion of liver cancer metabolism. We found that insulin increased pyruvate kinase M2 (PKM2) expression through reactive oxygen species (ROS) for regulating glucose consumption and lactate production, key process of glycolysis in hepatocellular carcinoma HepG2 and Bel7402 cells. Interestingly, insulin-induced ROS was found responsible for the suppression of miR-145 and miR-128, and forced expression of either miR-145 or miR-128 was sufficient to abolish insulin-induced PKM2 expression. Furthermore, the knockdown of PKM2 expression also inhibited cancer cell growth and insulin-induced glucose consumption and lactate production, suggesting that PKM2 is a functional downstream effecter of insulin. Taken together, this study would provide a new insight into the mechanism of insulin-induced glycolysis.

Li, Qi; Liu, Xue; Yin, Yu; Zheng, Ji-Tai; Jiang, Cheng-Fei; Wang, Jing; Shen, Hua; Li, Chong-Yong; Wang, Min; Liu, Ling-Zhi; Jiang, Bing-Hua

2014-01-01

136

Measurement of D ?± meson production and F 2 c in deep-inelastic scattering at HERA  

Microsoft Academic Search

The inclusive production of D?±(2010) mesons in deep-inelastic scattering is studied with the H1 detector at HERA. In the kinematic region 1production of 8.50±0.42(stat.)+1.21?1.00(syst.) nb is measured in the visible range ptD?>1.5 GeV and |?D?|<1.5. Single and double differential inclusive D?± meson cross sections are compared to perturbative QCD calculations in two

C. Adloff; V. Andreev; B. Andrieu; T. Anthonis; V. Arkadov; A. Astvatsatourov; A. Babaev; J. Bähr; P. Baranov; E. Barrelet; W. Bartel; P. Bate; A. Beglarian; O. Behnke; C. Beier; A. Belousov; T. Benisch; Ch. Berger; T. Berndt; J. C. Bizot; V. Boudry; W. Braunschweig; V. Brisson; H.-B. Bröker; D. P. Brown; W. Brückner; D. Bruncko; J. Bürger; F. W. Büsser; A. Bunyatyan; G. Buschhorn; A. J. Campbell; T. Carli; S. Caron; D. Clarke; B. Clerbaux; C. Collard; J. G. Contreras; Y. R. Coppens; J. A. Coughlan; M.-C. Cousinou; B. E. Cox; G. Cozzika; J. Cvach; J. B. Dainton; W. D. Dau; K. Daum; M. Davidsson; B. Delcourt; N. Delerue; R. Demirchyan; C. Diaconu; J. Dingfelder; P. Dixon; V. Dodonov; J. D. Dowell; A. Droutskoi; C. Duprel; G. Eckerlin; D. Eckstein; V. Efremenko; S. Egli; R. Eichler; F. Eisele; E. Eisenhandler; M. Ellerbrock; E. Elsen; M. Erdmann; W. Erdmann; P. J. W. Faulkner; L. Favart; A. Fedotov; R. Felst; J. Ferencei; S. Ferron; M. Fleischer; Y. H. Fleming; G. Flügge; A. Fomenko; I. Foresti; J. Formánek; G. Franke; E. Gabathuler; K. Gabathuler; J. Garvey; J. Gassner; R. Gerhards; C. Gerlich; S. Ghazaryan; L. Goerlich; N. Gogitidze; M. Goldberg; C. Goodwin; C. Goodwin; H. Grässler; T. Greenshaw; G. Grindhammer; T. Hadig; D. Haidt; L. Hajduk; W. J. Haynes; B. Heinemann; G. Heinzelmann; R. C. W. Henderson; S. Hengstmann; H. Henschel; R. Heremans; G. Herrera; I. Herynek; M. Hildebrandt; K. H. Hiller; J. Hladký; P. Höting; D. Hoffmann; R. Horisberger; S. Hurling; M. Ibbotson; Ç. ??sever; M. Jacquet; L. Janauschek; D. M. Jansen; X. Janssen; V. Jemanov; L. Jönsson; D. P. Johnson; M. A. S. Jones; H. Jung; H. K. Kästli; D. Kant; M. Kapichine; O. Karschnick; F. Keil; N. Keller; J. Kennedy; I. R. Kenyon; S. Kermiche; C. Kiesling; P. Kjellberg; M. Klein; C. Kleinwort; T. Kluge; G. Knies; B. Koblitz; S. D. Kolya; V. Korbel; P. Kostka; S. K. Kotelnikov; R. Koutouev; A. Koutov; H. Krehbiel; J. Kroseberg; K. Krüger; A. Küpper; T. Kuhr; T. Kur?a; R. Lahmann; D. Lamb; M. P. J. Landon; W. Lange; T. Laštovi?ka; P. Laycock; E. Lebailly; A. Lebedev; B. Leißner; R. Lemrani; V. Lendermann; S. Levonian; M. Lindstroem; B. List; E. Lobodzinska; B. Lobodzinski; A. Loginov; N. Loktionova; V. Lubimov; S. Lüders; D. Lüke; L. Lytkin; H. Mahlke-Krüger; N. Malden; E. Malinovski; I. Malinovski; R. Mara?ek; P. Marage; J. Marks; R. Marshall; H.-U. Martyn; J. Martyniak; S. J. Maxfield; D. Meer; A. Mehta; K. Meier; P. Merkel; A. B. Meyer; H. Meyer; J. Meyer; P.-O. Meyer; S. Mikocki; D. Milstead; T. Mkrtchyan; R. Mohr; S. Mohrdieck; M. N. Mondragon; F. Moreau; A. Morozov; J. V. Morris; K. Müller; P. Mur??n; V. Nagovizin; B. Naroska; J. Naumann; Th. Naumann; G. Nellen; P. R. Newman; T. C. Nicholls; F. Niebergall; C. Niebuhr; O. Nix; G. Nowak; J. E. Olsson; D. Ozerov; V. Panassik; C. Pascaud; G. D. Patel; M. Peez; E. Perez; J. P. Phillips; D. Pitzl; R. Pöschl; I. Potachnikova; B. Povh; K. Rabbertz; G. Rädel; J. Rauschenberger; P. Reimer; B. Reisert; D. Reyna; C. Risler; E. Rizvi; P. Robmann; R. Roosen; A. Rostovtsev; S. Rusakov; K. Rybicki; D. P. C. Sankey; J. Scheins; F.-P. Schilling; D. Schmidt; S. Schmitt; M. Schneider; L. Schoeffel; A. Schöning; T. Schörner; V. Schröder; H.-C. Schultz-Coulon; K. Sedlák; F. Sefkow; V. Shekelyan; I. Sheviakov; L. N. Shtarkov; Y. Sirois; T. Sloan; P. Smirnov; V. Solochenko; Y. Soloviev; D. South; V. Spaskov; A. Specka; H. Spitzer; R. Stamen; B. Stella; J. Stiewe; U. Straumann; M. Swart; M. Taševský; V. Tchernyshov; S. Tchetchelnitski; G. Thompson; P. D. Thompson; N. Tobien; D. Traynor; P. Truöl; G. Tsipolitis; I. Tsurin; J. Turnau; J. E. Turney; E. Tzamariudaki; S. Udluft; A. Usik; S. Valkár; A. Valkárová; C. Vallée; S. Vassiliev; Y. Vazdik; A. Vichnevski; K. Wacker; R. Wallny; B. Waugh; G. Weber; M. Weber; D. Wegener; C. Werner; M. Werner; N. Werner; G. White; S. Wiesand; T. Wilksen; M. Winde; G.-G. Winter; Ch. Wissing; M. Wobisch; E. Wünsch; A. C. Wyatt; J. Žá?ek; J. Zálešák; Z. Zhang; A. Zhokin; F. Zomer; J. Zsembery; M. zur Nedden

2002-01-01

137

Jet production in highQ 2 deep-inelastic ep scattering at HERA  

Microsoft Academic Search

Two-jet production in deep-inelastic electron-proton scattering has been\\u000astudied for $160production are compared to perturbative\\u000anext-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. Jele?; D. Kisielewska; T. Kowalski; E. Rulikowska-Zar?bska; L. Suszycki; J. Zaj?c; A. Kota?ski; M. Przybycie?; I. A. T. Bauerdick; U. Behrens; H. Beier; J. K. Bienlein; C. Coldewey; O. Deppe; K. Desler; G. Drews; M. Flasi?ski; 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. Ma?czak; 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. 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. Peso; J. Puga; J. Terron; J. F. 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. Kamps; P. Kooijman; A. Kruse; H. Tiecke; W. Verkerke; M. Vreeswijk; L. Wiggers; E. Wolf; R. 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. Corso; M. 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. 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; A. Solano; A. Staiano; M. Dardo

1995-01-01

138

Nitric Oxide and Reactive Oxygen Species Production Causes Progressive Damage in Rats after Cessation of Silica Inhalation  

Microsoft Academic Search

Our laboratory has previously reported results from a rat silica inhalation study which determined that, even after silica exposure ended, pulmonary inflammation and damage progressed with subsequent fibrosis development. In the present study, the re- lationship between silica exposure, nitric oxide (NO) and reactive oxygen species (ROS) production, and the resultant pulmonary damage is investigated in this model. Rats were

D. W. Porter; L. L. Millecchia; P. Willard; V. A. Robinson; D. Ramsey; J. McLaurin; A. Khan; K. Brumbaugh; C. M. Beighley; A. Teass; V. Castranova

2005-01-01

139

Decreased production of reactive oxygen intermediates is an early event during in vitro apoptosis of rat thymocytes  

Microsoft Academic Search

Thymocyte apoptosis is one of the best characterized experimental models of apoptosis that can be induced by a variety of stimuli such as glucocorticoids, ionizing radiation, antibodies, and toxins. Recently, it has been suggested that oxidative stress is a common mediator of apoptosis. However, little is known about the production and possible function of reactive oxygen intermediates (ROI) in thymocytes.

Ji-Feng Wang; Thomas R. Jerrells; John J. Spitzer

1996-01-01

140

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

141

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

142

Mitochondrial Reactive Oxygen Species Production in Excitable Cells: Modulators of Mitochondrial and Cell Function  

PubMed Central

Abstract The mitochondrion is a major source of reactive oxygen species (ROS). Superoxide (O2•?) is generated under specific bioenergetic conditions at several sites within the electron-transport system; most is converted to H2O2 inside and outside the mitochondrial matrix by superoxide dismutases. H2O2 is a major chemical messenger that, in low amounts and with its products, physiologically modulates cell function. The redox state and ROS scavengers largely control the emission (generation scavenging) of O2•?. Cell ischemia, hypoxia, or toxins can result in excess O2•? production when the redox state is altered and the ROS scavenger systems are overwhelmed. Too much H2O2 can combine with Fe2+ complexes to form reactive ferryl species (e.g., Fe(IV)?=?O•). In the presence of nitric oxide (NO•), O2•? forms the reactant peroxynitrite (ONOO?), and ONOOH-induced nitrosylation of proteins, DNA, and lipids can modify their structure and function. An initial increase in ROS can cause an even greater increase in ROS and allow excess mitochondrial Ca2+ entry, both of which are factors that induce cell apoptosis and necrosis. Approaches to reduce excess O2•? emission include selectively boosting the antioxidant capacity, uncoupling of oxidative phosphorylation to reduce generation of O2•? by inducing proton leak, and reversibly inhibiting electron transport. Mitochondrial cation channels and exchangers function to maintain matrix homeostasis and likely play a role in modulating mitochondrial function, in part by regulating O2•? generation. Cell-signaling pathways induced physiologically by ROS include effects on thiol groups and disulfide linkages to modify posttranslationally protein structure to activate/inactivate specific kinase/phosphatase pathways. Hypoxia-inducible factors that stimulate a cascade of gene transcription may be mediated physiologically by ROS. Our knowledge of the role played by ROS and their scavenging systems in modulation of cell function and cell death has grown exponentially over the past few years, but we are still limited in how to apply this knowledge to develop its full therapeutic potential. Antioxid. Redox Signal. 11, 1373–1414.

Camara, Amadou K. S.

2009-01-01

143

Real-time monitoring of reactive oxygen species production during differentiation of human monocytic cell lines (THP1)  

Microsoft Academic Search

Human monocytic leukemia cell line THP-1 differentiates into macrophages by phorbol myristate acetate (PMA) treatment. We report real-time monitoring of reactive oxygen species (ROS) production during the differentiation process. The production of ROS by THP-1 with several hours time scale has been detected using electrochemical and chemiluminescence methods. The increase in oxidation current derived from ROS arising from THP-1 was

Shigenobu Kasai; Hitoshi Shiku; Yu-suke Torisawa; Hiroyuki Noda; Jun Yoshitake; Takuo Shiraishi; Tomoyuki Yasukawa; Toshiaki Watanabe; Tomokazu Matsue; Tetsuhiko Yoshimura

2005-01-01

144

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

145

Cobalt Protoporphyrin Induces HO-1 Expression Mediated Partially by FOXO1 and Reduces Mitochondria-Derived Reactive Oxygen Species Production  

PubMed Central

Background Reactive oxygen species arise in the mitochondria as byproducts of respiration and oxidase activity and have important roles in many physiological and pathophysiological conditions. The level of reactive oxygen species is regulated by a number of enzymes and physiological antioxidants, including HO-1, Sod2, catalase and COX-2, etc. And HO-1 against oxidative stress requires an increase in stress-responsive genes, such as Sod2 and catalase. Especially for the activity of HO-1, cobalt protoporphyrin is known to be a potent and effective inducer in many tissues. The transcription factor, FOXO1 is resistant to oxidative stress through downregulating reactive oxygen species production. Previous study showed that FOXO1 induces HO-1 expression by binding to HO-1 promoter. The question whether cobalt protoporphyrin induces HO-1 expression mediated by FOXO1 and subsequently lessens reactive oxygen species production remains to be elucidated. Results Cobalt protoporphyrin enhances the expression of FOXO1 and facilitates FOXO1 binding to HO-1 promoter and increasing its transcriptional activity without influencing the FOXO1 protein stability. CoPP induces HO-1 and other oxidative stress-responsive genes expression, such as catalase, cytochrome c, Sod2, and COX-2, and decreases mitochondria-derived reactive oxygen species production, which are mediated partially by FOXO1. Conclusions Cobalt protoporphyrin induces HO-1 and other oxidative stress-responsive genes expression mediated partially by FOXO1, and has an important role in reducing cellular reactive oxygen species level. Cobalt protoporphyrin may be a more promising therapeutic agent to upregulate some antioxidantive genes.

Li, Meixia; Xu, Haifeng; Zuo, Jin; Fang, Fude; Chang, Yongsheng

2013-01-01

146

Characterisation and O 2 titration of CO islands on Pt 100: helium atom scattering and reactive sticking probability measurements  

NASA Astrophysics Data System (ADS)

Thermal energy atom scattering (TEAS) has been used simultaneously with molecular beam adsorption and thermal desorption to probe the lateral distribution of CO on a Pt 100 single-crystal surface. On the initial hex-R phase at 350 K, (1 × 1) island growth occurs at a constant local coverage ( ?(1 × 1)CO) of 0.4 ML. However, during desorption the surface remains wholly in the (1 × 1) state until ( ?(1 × 1)CO) ? 0.25 ML. Subsequent reconstruction to hex occurs at a constant local coverage of 0.19 ML in the remaining (1 × 1) domains. Hysteresis is not observed for the pre-prepared (1 × 1) surface, on which a random CO distribution is observed during adsorption. The scattering cross-section ? for a single CO molecule on the hex-R and (1 × 1) surfaces at 350 K has been determined as 71 ± 10 and 130 ± 18Å 2 respectively. The behaviour during oxidation of (1 × 1)-CO islands on the initial hex-R surface prepared by either adsorption or desorption is found to be consistent with the TEAS data. The first sticking probabilities for O 2 and CO on the CO ad-freed and O ad-freed (1 × 1) phase of Pt 100 are also reported.

Pasteur, A. T.; Guo, X.-C.; Ali, T.; Gruyters, M.; King, D. A.

1996-11-01

147

Paclitaxel induces vascular endothelial growth factor expression through reactive oxygen species production.  

PubMed

The antineoplastic drug paclitaxel is known to block cells in the G2/M phase of the cell cycle through stabilization of microtubules. The development of paclitaxel resistance in tumors is one of the most significant obstacles to successful therapy. Vascular endothelial growth factor (VEGF) and hypoxia-inducible factor 1 (HIF-1) are important regulators of neovascularization. HIF-1 regulates VEGF expression at the transcriptional level. Here, we investigated whether paclitaxel treatment affects VEGF expression for the development of paclitaxel resistance. Paclitaxel treatment induced dose-dependent cell death and increased VEGF expression. Paclitaxel also induced nuclear factor-kappaB activation and stabilized HIF-1alpha, which stimulated luciferase activity of HIF-1alpha response element on VEGF gene. As paclitaxel treatment produced reactive oxygen species (ROS), VEGF expression was increased by H2O2 treatment and reduced by various ROS scavengers such as N-acetyl-L-cysteine, pyrrolidine dithiocarbamate and diphenylene iodonium. Paclitaxel-induced cell death was aggravated by incubation with those ROS scavengers. Collectively, this suggests that paclitaxel-induced VEGF expression could be mediated by paclitaxel-induced ROS production through nuclear factor-kappaB activation and HIF-1alpha stabilization, which could affect resistance induction to antitumor therapeutics during cancer treatment. PMID:18322419

Kim, Hyun Sun; Oh, Jin Mi; Jin, Dong Hoon; Yang, Kyu-Hwan; Moon, Eun-Yi

2008-01-01

148

Reactive oxygen species production in mitochondria of human gingival fibroblast induced by blue light irradiation.  

PubMed

In recent years, it has become well known that the production of reactive oxygen species (ROS) induced by blue-light irradiation causes adverse effects of photo-aging, such as age-related macular degeneration of the retina. Thus, orange-tinted glasses are used to protect the retina during dental treatment involving blue-light irradiation (e.g., dental resin restorations or tooth bleaching treatments). However, there are few studies examining the effects of blue-light irradiation on oral tissue. For the first time, we report that blue-light irradiation by quartz tungsten halogen lamp (QTH) or light-emitting diode (LED) decreased cell proliferation activity of human gingival fibroblasts (HGFs) in a time-dependent manner (<5 min). Additionally, in a morphological study, the cytotoxic effect was observed in the cell organelles, especially the mitochondria. Furthermore, ROS generation induced by the blue-light irradiation was detected in mitochondria of HGFs using fluorimetry. In all analyses, the cytotoxicity was significantly higher after LED irradiation compared with cytotoxicity after QTH irradiation. These results suggest that blue light irradiation, especially by LED light sources used in dental aesthetic treatment, might have adverse effects on human gingival tissue. Hence, this necessitates the development of new dental aesthetic treatment methods and/or techniques to protect HGFs from blue light irradiation during dental therapy. PMID:24141287

Yoshida, Ayaka; Yoshino, Fumihiko; Makita, Tetsuya; Maehata, Yojiro; Higashi, Kazuyoshi; Miyamoto, Chihiro; Wada-Takahashi, Satoko; Takahashi, Shun-suke; Takahashi, Osamu; Lee, Masaichi Chang-il

2013-12-01

149

Reactive nitrogen species block cell cycle re-entry through sustained production of hydrogen peroxide.  

PubMed

Endogenous sources of reactive nitrogen species (RNS) act as second messengers in a variety of cell signaling events, whereas environmental sources of RNS like nitrogen dioxide (NO2) inhibit cell survival and growth through covalent modification of cellular macromolecules. To examine the effects of RNS on cell cycle progression, murine type II alveolar C10 cells arrested in G0 by serum deprivation were exposed to either NO2 or SIN-1, a generator of RNS, during cell cycle re-entry. In serum-stimulated cells, RNS did not prevent the immediate early gene response by AP-1, but rather blocked cyclin D1 gene expression, resulting cell cycle arrest at the boundary between G0 and G1. Dichlorofluorescin diacetate (DCF) fluorescence indicated that RNS induced sustained production of intracellular hydrogen peroxide (H2O2), which normally is produced only transiently in response to serum growth factors. Loading cells with catalase did not diminish the formation of 3-nitrotyrosine on the cell surface, but rather prevented enhanced DCF fluorescence and rescued cyclin D1 expression and S phase entry. These studies indicate environmental RNS interfere with cell cycle re-entry through an H2O2-dependent mechanism that influences expression of cyclin D1 and progression from G0 to the G1 phase of the cell cycle. PMID:12600834

Yuan, Ziqiang; Schellekens, Harriet; Warner, Loraine; Janssen-Heininger, Yvonne; Burch, Peter; Heintz, Nicholas H

2003-06-01

150

In vitro reactive oxygen species production by histatins and copper(I,II).  

PubMed

The ability of the histidine-rich peptides, histatin-5 (Hst-5) and histatin-8 (Hst-8), to support the generation of reactive oxygen species during the Cu-catalyzed oxidation of ascorbate and cysteine has been evaluated. High levels of hydrogen peroxide (70-580 mol/mol Cu/h) are produced by aqueous solutions containing Cu(II), Hst-8 or Hst-5, and a reductant, either ascorbate or cysteine, as determined by the postreaction Amplex Red assay. When the reactions are conducted in the presence of superoxide dismutase, the total hydrogen peroxide produced is decreased, more so in the presence of the peptides (up to 50%), suggesting the intermediacy of superoxide in these reactions. On the other hand, the presence of sodium azide or sodium formate, traps for hydroxyl radicals, has no appreciable effect on the total hydrogen peroxide production for the Cu-Hst systems. EPR spin-trapping studies using 5-(2,2-dimethyl-1,3-propoxy cyclophosphoryl)-5-methyl-1-pyrroline N-oxide (CYPMPO) in the cysteine-Cu(II) reactions reveal the formation of the CYPMPO-hydroperoxyl and CYPMPO-hydroxyl radical adducts in the presence of Hst-8, whereas only the latter was observed with Cu alone. PMID:18975018

Houghton, Eric A; Nicholas, Kenneth M

2009-02-01

151

Reactive Oxygen Species Production and Brugia pahangi Survivorship in Aedes polynesiensis with Artificial Wolbachia Infection Types  

PubMed Central

Heterologous transinfection with the endosymbiotic bacterium Wolbachia has been shown previously to induce pathogen interference phenotypes in mosquito hosts. Here we examine an artificially infected strain of Aedes polynesiensis, the primary vector of Wuchereria bancrofti, which is the causative agent of Lymphatic filariasis (LF) throughout much of the South Pacific. Embryonic microinjection was used to transfer the wAlbB infection from Aedes albopictus into an aposymbiotic strain of Ae. polynesiensis. The resulting strain (designated “MTB”) experiences a stable artificial infection with high maternal inheritance. Reciprocal crosses of MTB with naturally infected wild-type Ae. polynesiensis demonstrate strong bidirectional incompatibility. Levels of reactive oxygen species (ROS) in the MTB strain differ significantly relative to that of the wild-type, indicating an impaired ability to regulate oxidative stress. Following a challenge with Brugia pahangi, the number of filarial worms achieving the infective stage is significantly reduced in MTB as compared to the naturally infected and aposymbiotic strains. Survivorship of MTB differed significantly from that of the wild-type, with an interactive effect between survivorship and blood feeding. The results demonstrate a direct correlation between decreased ROS levels and decreased survival of adult female Aedes polynesiensis. The results are discussed in relation to the interaction of Wolbachia with ROS production and antioxidant expression, iron homeostasis and the insect immune system. We discuss the potential applied use of the MTB strain for impacting Ae. polynesiensis populations and strategies for reducing LF incidence in the South Pacific.

Andrews, Elizabeth S.; Crain, Philip R.; Fu, Yuqing; Howe, Daniel K.; Dobson, Stephen L.

2012-01-01

152

Autophagy proteins control goblet cell function by potentiating reactive oxygen species production.  

PubMed

Delivery of granule contents to epithelial surfaces by secretory cells is a critical physiologic process. In the intestine, goblet cells secrete mucus that is required for homeostasis. Autophagy proteins are required for secretion in some cases, though the mechanism and cell biological basis for this requirement remain unknown. We found that in colonic goblet cells, proteins involved in initiation and elongation of autophagosomes were required for efficient mucus secretion. The autophagy protein LC3 localized to intracellular multi-vesicular vacuoles that were consistent with a fusion of autophagosomes and endosomes. Using cultured intestinal epithelial cells, we found that NADPH oxidases localized to and enhanced the formation of these LC3-positive vacuoles. Both autophagy proteins and endosome formation were required for maximal production of reactive oxygen species (ROS) derived from NADPH oxidases. Importantly, generation of ROS was critical to control mucin granule accumulation in colonic goblet cells. Thus, autophagy proteins can control secretory function through ROS, which is in part generated by LC3-positive vacuole-associated NADPH oxidases. These findings provide a novel mechanism by which autophagy proteins can control secretion. PMID:24185898

Patel, Khushbu K; Miyoshi, Hiroyuki; Beatty, Wandy L; Head, Richard D; Malvin, Nicole P; Cadwell, Ken; Guan, Jun-Lin; Saitoh, Tatsuya; Akira, Shizuo; Seglen, Per O; Dinauer, Mary C; Virgin, Herbert W; Stappenbeck, Thaddeus S

2013-12-11

153

Concurrent detection of secreted products from human lymphocytes by microengraving: cytokines and antigen-reactive antibodies.  

PubMed

Cell surface determinants, cytokines and antibodies secreted by hematopoietic cells are used to classify their lineage and function. Currently available techniques are unable to elucidate multiple secreted proteins while also assigning phenotypic surface-displayed markers to the individual living cells. Here, a soft lithographic method, microengraving, was adapted for the multiplexed interrogation of populations of individual human peripheral blood mononuclear cells for secreted cytokines (IFN-gamma and IL-6), antigen-specific antibodies, and lineage-specific surface-expressed markers. Application of the method to a clinical sample from a recent-onset Type 1 diabetic subject with a positive titer of anti-insulin antibodies showed that approximately 0.58% of circulating CD19(+) B cells secreted proinsulin-reactive antibodies of the IgG isotype and 2-3% of circulating cells secreted IL-6. These data demonstrate the utility of microengraving for interrogating multiple phenotypes of single human cells concurrently and for detecting rare populations of cells by their secreted products. PMID:18675591

Bradshaw, Elizabeth M; Kent, Sally C; Tripuraneni, Vinay; Orban, Tihamer; Ploegh, Hidde L; Hafler, David A; Love, J Christopher

2008-10-01

154

Production of a reactive metabolite of troglitazone by electrochemical oxidation performed in nonaqueous medium  

Microsoft Academic Search

In order to confirm the existence of reactive metabolites by LC-MS\\/MS analysis, they should be modified into stable compounds, because some reactive metabolites generated by biotransformation induce drug toxicity; however, they are unstable, with very short lives, and cannot be detected in their intact forms. To overcome these problems, electrochemical oxidation of troglitazone was performed in nonaqueous medium, since such

Kayoko Tahara; Takashi Nishikawa; Yutaka Hattori; Shiro Iijima; Yukiko Kouno; Yoshihiro Abe

2009-01-01

155

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

156

Reactive oxygen species production and redox state in parthenogenetic and sperm-mediated bovine oocyte activation.  

PubMed

The knowledge concerning redox and reactive oxygen species (ROS)-mediated regulation of early embryo development is scarce and remains controversial. The aim of this work was to determine ROS production and redox state during early in vitro embryo development in sperm-mediated and parthenogenetic activation of bovine oocytes. Sperm-mediated oocyte activation was carried out in IVF-modified synthetic oviductal fluid (mSOF) with frozen-thawed semen. Parthenogenetic activation was performed in TALP plus ionomycin and then in IVF-mSOF with 6-dimethylaminopurine plus cytochalasin B. Embryos were cultured in IVF-mSOF. ROS and redox state were determined at each 2-h interval (7-24?h from activation) by 2',7'-dichlorodihydrofluorescein diacetate and RedoxSensor Red CC-1 fluorochromes respectively. ROS levels and redox state differed between activated and non-activated oocytes (P<0.05 by ANOVA). In sperm-activated oocytes, an increase was observed between 15 and 19?h (P<0.05). Conversely, in parthenogenetically activated oocytes, we observed a decrease at 9?h (P<0.05). In sperm-activated oocytes, ROS fluctuated throughout the 24?h, presenting peaks around 7, 19, and 24?h (P<0.05), while in parthenogenetic activation, peaks were detected at 7, 11, and 17?h (P<0.05). In the present work, we found clear distinctive metabolic patterns between normal and parthenogenetic zygotes. Oxidative activity and ROS production are an integral part of bovine zygote behavior, and defining a temporal pattern of change may be linked with developmental competence. PMID:23630331

Morado, S; Cetica, P; Beconi, M; Thompson, J G; Dalvit, G

2013-05-01

157

Non-thermal Plasma Induces Apoptosis in Melanoma Cells via Production of Intracellular Reactive Oxygen Species  

PubMed Central

Non-thermal atmospheric pressure dielectric barrier discharge (DBD) plasma may provide a novel approach to treat malignancies via induction of apoptosis. The purpose of this study was to evaluate the potential of DBD plasma to induce apoptosis in melanoma cells. Melanoma cells were exposed to plasma at doses that did not induce necrosis, and cell viability and apoptotic activity were evaluated by Trypan blue exclusion test, Annexin-V/PI staining, caspase-3 cleavage, and TUNEL® analysis. Trypan blue staining revealed that non-thermal plasma treatment significantly decreased the viability of cells in a dose-dependent manner 3 and 24 h after plasma treatment. Annexin-V/PI staining revealed a significant increase in apoptosis in plasma-treated cells at 24, 48, and 72 h post-treatment (p<0.001). Caspase-3 cleavage was observed 48 h post-plasma treatment at a dose of 15 J/cm2. TUNEL® analysis of plasma-treated cells demonstrated an increase in apoptosis at 48 and 72 h post-treatment (p<0.001) at a dose of 15 J/cm2. Pre-treatment with N-acetyl-L-cysteine (NAC), an intracellular reactive oxygen species (ROS) scavenger, significantly decreased apoptosis in plasma-treated cells at 5 and 15 J/cm2. Plasma treatment induces apoptosis in melanoma cells through a pathway that appears to be dependent on production of intracellular ROS. DBD plasma production of intracellular ROS leads to dose-dependent DNA damage in melanoma cells, detected by ?-H2AX, which was completely abrogated by pre-treating cells with ROS scavenger, NAC. Plasma-induced DNA damage in turn may lead to the observed plasma-induced apoptosis. Since plasma is non-thermal, it may be used to selectively treat malignancies.

Sensenig, Rachel; Kalghatgi, Sameer; Cerchar, Ekaterina; Fridman, Gregory; Shereshevsky, Alexey; Torabi, Behzad; Arjunan, Krishna Priya; Podolsky, Erica; Fridman, Alexander; Friedman, Gary; Azizkhan-Clifford, Jane; Brooks, Ari D.

2012-01-01

158

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

159

Modulation of cholinergic airway reactivity and nitric oxide production by endogenous arginase activity.  

PubMed

Cholinergic airway constriction is functionally antagonized by agonist-induced constitutive nitric oxide synthase (cNOS)-derived nitric oxide (NO). Since cNOS and arginase, which hydrolyzes L-arginine to L-ornithine and urea, use L-arginine as a common substrate, competition between both enzymes for the substrate could be involved in the regulation of cholinergic airway reactivity. Using a perfused guinea-pig tracheal tube preparation, we investigated the modulation of methacholine-induced airway constriction by the recently developed, potent and specific arginase inhibitor N(Omega)-hydroxy-nor-L-arginine (nor-NOHA). Intraluminal (IL) administration of nor-NOHA caused a concentration-dependent inhibition of the maximal effect (E(max)) in response to IL methacholine, which was maximal in the presence of 5 microM nor-NOHA (E(max)=31.2+/-1.6% of extraluminal (EL) 40 mM KCl-induced constriction versus 51.6+/-2.1% in controls, P<0.001). In addition, the pEC(50) (-log(10) EC(50)) was slightly but significantly reduced in the presence of 5 microM nor-NOHA. The inhibition of E(max) by 5 microM nor-NOHA was concentration-dependently reversed by the NOS inhibitor N(Omega)-nitro-L-arginine methyl ester (L-NAME), reaching an E(max) of 89.4+/-7.7% in the presence of 0.5 mM L-NAME (P<0.01). A similar E(max) in the presence of 0.5 mM L-NAME was obtained in control preparations (85.2+/-9.7%, n.s.). In the presence of excess of exogenously applied L-arginine (5 mM), 5 microM nor-NOHA was ineffective (E(max)=33.1+/-5.8 versus 31.1+/-7.5% in controls, n.s.). The results indicate that endogenous arginase activity potentiates methacholine-induced airway constriction by inhibition of NO production, presumably by competition with cNOS for the common substrate, L-arginine. This finding may represent an important novel regulation mechanism of airway reactivity. PMID:10952667

Meurs, H; Hamer, M A; Pethe, S; Vadon-Le Goff, S; Boucher, J L; Zaagsma, J

2000-08-01

160

Modulation of cholinergic airway reactivity and nitric oxide production by endogenous arginase activity  

PubMed Central

Cholinergic airway constriction is functionally antagonized by agonist-induced constitutive nitric oxide synthase (cNOS)-derived nitric oxide (NO). Since cNOS and arginase, which hydrolyzes L-arginine to L-ornithine and urea, use L-arginine as a common substrate, competition between both enzymes for the substrate could be involved in the regulation of cholinergic airway reactivity. Using a perfused guinea-pig tracheal tube preparation, we investigated the modulation of methacholine-induced airway constriction by the recently developed, potent and specific arginase inhibitor N?-hydroxy-nor-L-arginine (nor-NOHA).Intraluminal (IL) administration of nor-NOHA caused a concentration-dependent inhibition of the maximal effect (Emax) in response to IL methacholine, which was maximal in the presence of 5??M nor-NOHA (Emax=31.2±1.6% of extraluminal (EL) 40?mM KCl-induced constriction versus 51.6±2.1% in controls, P<0.001). In addition, the pEC50 (?log10 EC50) was slightly but significantly reduced in the presence of 5??M nor-NOHA.The inhibition of Emax by 5??M nor-NOHA was concentration-dependently reversed by the NOS inhibitor N?-nitro-L-arginine methyl ester (L-NAME), reaching an Emax of 89.4±7.7% in the presence of 0.5?mM L-NAME (P<0.01). A similar Emax in the presence of 0.5?mM L-NAME was obtained in control preparations (85.2±9.7%, n.s.).In the presence of excess of exogenously applied L-arginine (5?mM), 5??M nor-NOHA was ineffective (Emax=33.1±5.8 versus 31.1±7.5% in controls, n.s.).The results indicate that endogenous arginase activity potentiates methacholine-induced airway constriction by inhibition of NO production, presumably by competition with cNOS for the common substrate, L-arginine. This finding may represent an important novel regulation mechanism of airway reactivity.

Meurs, Herman; Hamer, Marco A M; Pethe, Stephanie; Vadon-Le Goff, Sandrine; Boucher, Jean-Luc; Zaagsma, Johan

2000-01-01

161

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

162

Effects of PCBs on Reactive Oxygen Species (ROS) Production by the Immune Cells of Paracentrotus lividus (Echinodermata)  

Microsoft Academic Search

The impact of four PCB congeners: 3,3?,4,4?-tetrachlorobiphenyl (IUPAC congener #77), 3,3?,4,4?,5-pentachlorobiphenyl (IUPAC #126), 2,2?,4,4?,5,5?-hexachlorobiphenyl (IUPAC #153) and 3,3?,4,4?,5,5?-hexachlorobiphenyl (IUPAC #169) was investigated on the reactive oxygen species (ROS) production by coelomocytes of the echinoid Paracentrotus lividus, an important species in marine benthic ecosystems. PCBs were found to increase ROS production and to delay the time of peak production. These effects

G. Coteur; B. Danis; S. W. Fowler; J.-L. Teyssié; Ph. Dubois; M. Warnau

2001-01-01

163

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

164

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

Microsoft Academic Search

Inclusive production of D*± (2010) mesons in deep inelastic scattering has been measured with the ZEUS detector at DESY HERA using an integrated luminosity of 81.9 pb-1. The decay channel D*+-->D0pi+ with D0-->K-pi+ and corresponding antiparticle decay were used to identify D* mesons. Differential D* cross sections with 1.5

S. V. Chekanov; M. Derrick; D. Krakauer; J. H. Loizides; S. Magill; B. Musgrave; J. Repond; R. Yoshida; M. C. Mattingly; 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; G. Sartorelli; A. Zichichi; G. Aghuzumtsyan; D. Bartsch; I. Brock; S. Goers; H. Hartmann; E. Hilger; P. Irrgang; H.-P. Jakob; A. Kappes; U. F. Katz; O. Kind; U. Meyer; E. Paul; J. Rautenberg; R. Renner; A. Stifutkin; J. Tandler; K. C. Voss; M. Wang; A. Weber; D. S. Bailey; N. H. Brook; J. E. Cole; B. Foster; G. P. Heath; H. F. Heath; S. Robins; E. Rodrigues; J. Scott; R. J. Tapper; M. Wing; M. Capua; A. Mastroberardino; M. Schioppa; G. Susinno; J. Y. Kim; Y. K. Kim; J. H. Lee; I. T. Lim; M. Y. Pac; A. Caldwell; M. Helbich; X. Liu; B. Mellado; Y. Ning; S. Paganis; Z. Ren; W. B. Schmidke; F. Sciulli; J. Chwastowski; A. Eskreys; J. Figiel; K. Olkiewicz; P. Stopa; L. Zawiejski; L. Adamczyk; T. Bold; I. Grabowska-Bold; D. Kisielewska; A. M. Kowal; M. Kowal; T. Kowalski; M. Przybycien; L. Suszycki; D. Szuba; J. Szuba; A. Kotanski; W. Slominski; V. Adler; L. A. Bauerdick; 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; G. F. Hartner; S. Hillert; B. Kahle; U. Kötz; H. Kowalski; G. Kramberger; H. Labes; D. Lelas; B. Löhr; R. Mankel; I.-A. Melzer-Pellmann; C. N. Nguyen; D. Notz; A. E. Nuncio-Quiroz; M. C. Petrucci; A. Polini; A. Raval; L. Rurua; U. Schneekloth; U. Stoesslein; G. Wolf; C. Youngman; W. Zeuner; S. Schlenstedt; G. Barbagli; E. Gallo; C. Genta; P. G. Pelfer; A. Bamberger; A. Benen; N. Coppola; M. Bell; P. J. Bussey; A. T. Doyle; S. Hanlon; S. W. Lee; A. Lupi; D. H. Saxon; I. O. Skillicorn; I. Gialas; B. Bodmann; T. Carli; U. Holm; K. Klimek; N. Krumnack; E. Lohrmann; M. Milite; H. Salehi; P. Schleper; S. Stonjek; K. Wick; A. Ziegler; C. Collins-Tooth; C. Foudas; R. Gonçalo; K. R. Long; A. D. Tapper; P. Cloth; D. Filges; K. Nagano; K. Tokushuku; S. Yamada; Y. Yamazaki; M. Kataoka; A. N. Barakbaev; E. G. Boos; N. S. Pokrovskiy; B. O. Zhautykov; H. Lim; D. Son; K. Piotrzkowski; F. Barreiro; C. Glasman; O. González; L. Labarga; J. del Peso; E. Tassi; J. Terrón; M. Vázquez; 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; Yu. A. Golubkov; I. I. Katkov; L. A. Khein; I. A. Korzhavina; V. A. Kuzmin; B. B. Levchenko; O. Yu. Lukina; A. S. Proskuryakov; L. M. Shcheglova; N. N. Vlasov; S. A. Zotkin; S. Grijpink; E. Koffeman; P. Kooijman; E. Maddox; A. Pellegrino; S. Schagen; H. Tiecke; J. J. Velthuis; L. Wiggers; E. de Wolf; N. Brümmer; B. Bylsma; L. S. Durkin; T. Y. Ling; A. M. Cooper-Sarkar; A. Cottrell; R. C. Devenish; J. Ferrando; G. Grzelak; C. Gwenlan; S. Patel; M. R. Sutton; R. Walczak; 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; N. Pavel; H. Abramowicz; A. Gabareen; S. Kananov; A. Kreisel; A. Levy; M. Kuze; T. Abe; T. Fusayasu; S. Kagawa; T. Kohno; T. Tawara; T. Yamashita; R. Hamatsu; T. Hirose; M. Inuzuka; H. Kaji; S. Kitamura; K. Matsuzawa; T. Nishimura; M. Arneodo; M. I. Ferrero; V. Monaco; M. Ruspa; R. Sacchi; A. Solano; T. Koop; G. M. Levman; J. F. Martin; A. Mirea; J. M. Butterworth; R. Hall-Wilton; T. W. Jones; M. S. Lightwood; 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; L. K. Gladilin; D. Hochman; U. Karshon; M. Riveline; D. Kçira; S. Lammers; L. Li; D. D. Reeder; M. Rosin; A. A. Savin; W. H. Smith; A. Deshpande; S. Dhawan; P. B. Straub; S. Bhadra; C. D. Catterall; S. Fourletov; S. Menary; M. Soares; J. Standage

2004-01-01

165

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

166

Single Spin Asymmetry in Inclusive Hadron Production in pp Scattering from Collins Mechanism  

SciTech Connect

We study the Collins mechanism contribution to the single transverse spin asymmetry in inclusive hadron production in pp scattering p{up_arrow}p {yields} {pi}X from the leading jet fragmentation. The azimuthal asymmetric distribution of hadron in the jet leads to a single spin asymmetry for the produced hadron in the Lab frame. The effect is evaluated in a transverse momentum dependent model that takes into account the transverse momentum dependence in the fragmentation process. We find the asymmetry is comparable in size to the experimental observation at RHIC at {radical}s = 200GeV.

Yuan, Feng; Yuan, Feng

2008-04-14

167

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

168

QCD CORRECTIONS TO DILEPTON PRODUCTION NEAR PARTONIC THRESHOLD IN PP SCATTERING.  

SciTech Connect

We present a recent study of the QCD corrections to dilepton production near partonic threshold in transversely polarized {bar p}p scattering, We analyze the role of the higher-order perturbative QCD corrections in terms of the available fixed-order contributions as well as of all-order soft-gluon resummations for the kinematical regime of proposed experiments at GSI-FAIR. We find that perturbative corrections are large for both unpolarized and polarized cross sections, but that the spin asymmetries are stable. The role of the far infrared region of the momentum integral in the resummed exponent and the effect of the NNLL resummation are briefly discussed.

SHIMIZU, H.; STERMAN, G.; VOGELSANG, W.; YOKOYA, H.

2005-10-02

169

Three-jet production in deep-inelastic scattering at HERA  

Microsoft Academic Search

Three-jet production is studied for the first time in deep-inelastic positron–proton scattering. The measurement carried out with the H1 detector at HERA covers a large range of four-momentum transfer squared 5

C. Adloff; V. Andreev; B. Andrieu; T. Anthonis; V. Arkadov; A. Astvatsatourov; I. Ayyaz; A. Babaev; J. Bähr; P. Baranov; E. Barrelet; W. Bartel; P. Bate; A. Beglarian; O. Behnke; C. Beier; A. Belousov; T. Benisch; Ch. Berger; T. Berndt; J. C. Bizot; V. Boudry; W. Braunschweig; V. Brisson; H.-B. Bröker; D. P. Brown; W. Brückner; P. Bruel; D. Bruncko; J. Bürger; F. W. Büsser; A. Bunyatyan; H. Burkhardt; A. Burrage; G. Buschhorn; A. J. Campbell; T. Carli; S. Caron; D. Clarke; B. Clerbaux; C. Collard; J. G. Contreras; Y. R. Coppens; J. A. Coughlan; M.-C. Cousinou; B. E. Cox; G. Cozzika; J. Cvach; J. B. Dainton; W. D. Dau; K. Daum; M. Davidsson; B. Delcourt; N. Delerue; R. Demirchyan; C. Diaconu; J. Dingfelder; P. Dixon; V. Dodonov; J. D. Dowell; A. Droutskoi; C. Duprel; G. Eckerlin; D. Eckstein; V. Efremenko; S. Egli; R. Eichler; F. Eisele; E. Eisenhandler; M. Ellerbrock; E. Elsen; M. Erdmann; W. Erdmann; P. J. W. Faulkner; L. Favart; A. Fedotov; R. Felst; J. Ferencei; S. Ferron; M. Fleischer; Y. H. Fleming; G. Flügge; A. Fomenko; I. Foresti; J. Formánek; G. Franke; E. Gabathuler; K. Gabathuler; J. Garvey; J. Gassner; R. Gerhards; C. Gerlich; S. Ghazaryan; L. Goerlich; N. Gogitidze; M. Goldberg; C. Goodwin; C. Goodwin; H. Grässler; T. Greenshaw; G. Grindhammer; T. Hadig; D. Haidt; L. Hajduk; W. J. Haynes; B. Heinemann; G. Heinzelmann; A. Heister; R. C. W. Henderson; S. Hengstmann; H. Henschel; R. Heremans; G. Herrera; I. Herynek; M. Hildebrandt; K. H. Hiller; J. Hladký; P. Höting; D. Hoffmann; R. Horisberger; S. Hurling; M. Ibbotson; Ç. ??sever; M. Jacquet; L. Janauschek; D. M. Jansen; X. Janssen; V. Jemanov; L. Jönsson; D. P. Johnson; M. A. S. Jones; H. Jung; H. K. Kästli; D. Kant; M. Kapichine; O. Karschnick; F. Keil; N. Keller; J. Kennedy; I. R. Kenyon; S. Kermiche; C. Kiesling; P. Kjellberg; M. Klein; C. Kleinwort; G. Knies; B. Koblitz; S. D. Kolya; V. Korbel; P. Kostka; S. K. Kotelnikov; R. Koutouev; A. Koutov; M. W. Krasny; H. Krehbiel; J. Kroseberg; K. Krüger; A. Küpper; T. Kuhr; T. Kur?a; R. Lahmann; D. Lamb; M. P. J. Landon; W. Lange; T. Laštovi?ka; P. Laycock; E. Lebailly; A. Lebedev; B. Leißner; R. Lemrani; V. Lendermann; S. Levonian; M. Lindstroem; B. List; E. Lobodzinska; B. Lobodzinski; A. Loginov; N. Loktionova; V. Lubimov; S. Lüders; D. Lüke; L. Lytkin; N. Magnussen; H. Mahlke-Krüger; N. Malden; E. Malinovski; I. Malinovski; R. Mara?ek; P. Marage; J. Marks; R. Marshall; H.-U. Martyn; J. Martyniak; S. J. Maxfield; D. Meer; A. Mehta; K. Meier; P. Merkel; A. B. Meyer; H. Meyer; J. Meyer; P.-O. Meyer; S. Mikocki; D. Milstead; T. Mkrtchyan; R. Mohr; S. Mohrdieck; M. N. Mondragon; F. Moreau; A. Morozov; J. V. Morris; K. Müller; P. Mur??n; V. Nagovizin; B. Naroska; J. Naumann; Th. Naumann; G. Nellen; P. R. Newman; T. C. Nicholls; F. Niebergall; C. Niebuhr; O. Nix; G. Nowak; T. Nunnemann; J. E. Olsson; D. Ozerov; V. Panassik; C. Pascaud; G. D. Patel; M. Peez; E. Perez; J. P. Phillips; D. Pitzl; R. Pöschl; I. Potachnikova; B. Povh; K. Rabbertz; G. Rädel; J. Rauschenberger; P. Reimer; B. Reisert; D. Reyna; S. Riess; C. Risler; E. Rizvi; P. Robmann; R. Roosen; A. Rostovtsev; C. Royon; S. Rusakov; K. Rybicki; D. P. C. Sankey; J. Scheins; F.-P. Schilling; D. Schmidt; S. Schmitt; M. Schneider; L. Schoeffel; A. Schöning; T. Schörner; V. Schröder; H.-C. Schultz-Coulon; K. Sedlák; F. Sefkow; V. Shekelyan; I. Sheviakov; L. N. Shtarkov; Y. Sirois; T. Sloan; P. Smirnov; V. Solochenko; Y. Soloviev; V. Spaskov; A. Specka; H. Spitzer; R. Stamen; J. Steinhart; B. Stella; A. Stellberger; J. Stiewe; U. Straumann; W. Struczinski; M. Swart; M. Taševský; V. Tchernyshov; S. Tchetchelnitski; G. Thompson; P. D. Thompson; N. Tobien; D. Traynor; P. Truöl; G. Tsipolitis; I. Tsurin; J. Turnau; J. E. Turney; E. Tzamariudaki; S. Udluft; A. Usik; S. Valkár; A. Valkárová; C. Vallée; S. Vassiliev; Y. Vazdik; A. Vichnevski; K. Wacker; R. Wallny; T. Walter; B. Waugh; G. Weber; M. Weber; D. Wegener; M. Werner; N. Werner; G. White; S. Wiesand; T. Wilksen; M. Winde; G.-G. Winter; Ch. Wissing; M. Wobisch; H. Wollatz; E. Wünsch; A. C. Wyatt; J. Žá?ek; J. Zálešák; Z. Zhang; A. Zhokin; F. Zomer; J. Zsembery; M. zur Nedden

2001-01-01

170

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

NASA Astrophysics Data System (ADS)

The heterogeneous reaction of Cl• radicals with submicron 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 vapours and introduced into the reactor, where chlorine atoms were 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 gas chromatography-mass spectrometer (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 analysis has 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 were identified by GC/MS. The formation of alcohols and monocarboxylic acids is also suspected. A reaction pathway for the main products and more functionalized species is proposed. 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. 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.

2013-12-01

171

NADPH oxidases: a perspective on reactive oxygen species production in tumor biology.  

PubMed

Abstract Significance: Reactive oxygen species (ROS) promote genomic instability, altered signal transduction, and an environment that can sustain tumor formation and growth. The NOX family of NADPH oxidases, membrane-bound epithelial superoxide and hydrogen peroxide producers, plays a critical role in the maintenance of immune function, cell growth, and apoptosis. The impact of NOX enzymes in carcinogenesis is currently being defined and may directly link chronic inflammation and NOX ROS-mediated tumor formation. Recent Advances: Increased interest in the function of NOX enzymes in tumor biology has spurred a surge of investigative effort to understand the variability of NOX expression levels in tumors and the effect of NOX activity on tumor cell proliferation. These initial efforts have demonstrated a wide variance in NOX distribution and expression levels across numerous cancers as well as in common tumor cell lines, suggesting that much remains to be discovered about the unique role of NOX-related ROS production within each system. Progression from in vitro cell line studies toward in vivo tumor tissue screening and xenograft models has begun to provide evidence supporting the importance of NOX expression in carcinogenesis. Critical Issues: A lack of universally available, isoform-specific antibodies and animal tumor models of inducible knockout or over-expression of NOX isoforms has hindered progress toward the completion of in vivo studies. Future Directions: In vivo validation experiments and the use of large, existing gene expression data sets should help define the best model systems for studying the NOX homologues in the context of cancer. Antioxid. Redox Signal. 20, 2873-2889. PMID:24156355

Meitzler, Jennifer L; Antony, Smitha; Wu, Yongzhong; Juhasz, Agnes; Liu, Han; Jiang, Guojian; Lu, Jiamo; Roy, Krishnendu; Doroshow, James H

2014-06-10

172

Chemical Characterization and Reactivity Testing of Fuel-Oxidizer Reaction Product (Test Report)  

NASA Technical Reports Server (NTRS)

The product of incomplete reaction of monomethylhydrazine (MMH) and nitrogen tetroxide (NTO) propellants, or fuel-oxidizer reaction product (FORP), has been hypothesized as a contributory cause of an anomaly which occurred in the chamber pressure (PC) transducer tube on the Reaction Control Subsystem (RCS) aft thruster 467 on flight STS-51. A small hole was found in the titanium-alloy PC tube at the first bend below the pressure transducer. It was surmised that the hole may have been caused by heat and pressure resulting from ignition of FORP. The NASA Johnson Space Center (JSC) White Sands Test Facility (WSTF) was requested to define the chemical characteristics of FORP, characterize its reactivity, and simulate the events in a controlled environment which may have lead to the Pc-tube failure. Samples of FORP were obtained from the gas-phase reaction of MMH with NTO under laboratory conditions, the pulsed firings of RCS thrusters with modified PC tubes using varied oxidizer or fuel lead times, and the nominal RCS thruster firings at WSTF and Kaiser-Marquardt. Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), accelerating rate calorimetry (ARC), ion chromatography (IC), inductively coupled plasma (ICP) spectrometry, thermogravimetric analysis (TGA) coupled to FTIR (TGA/FTIR), and mechanical impact testing were used to qualitatively and quantitatively characterize the chemical, thermal, and ignition properties of FORP. These studies showed that the composition of FORP is variable but falls within a limited range of compositions that depends on the fuel loxidizer ratio at the time of formation, composition of the post-formation atmosphere (reducing or oxidizing), and reaction or postreaction temperature. A typical composition contains methylhydrazinium nitrate (MMHN), ammonium nitrate (AN), methylammonium nitrate (MAN), and trace amounts of hydrazinium nitrate and 1,1-dimethylhydrazinium nitrate. The thermal decomposition reactions of FORP compositions used in this study were unremarkable, Neither the various compositions of FORP, the pure major components of FORP, nor mixtures of FORP with propellant-system corrosion products showed any unusual thermal activity when decomposed under laboratory conditions. Off-limit thruster operations were simulated by rapid mixing of liquid MMH and liquid NTO in a confined space. The test hardware was constructed with pressure- and temperature-measurement devices to determine if the expected fuel oxidizer reaction would result in increased energy release when FORP, FORP constituents, or propellant-system corrosion products were present. These tests demonstrated that FORP, MMHN, AN, or Inconel corrosion products can induce a mixture of MMH and NTO to produce component-damaging energies. The simulation-test program was not extensive enough to provide statistical probabilities for these events but did show that such events can occur. Damaging events required FORP or metal salts to be present at the initial mixing of MMH and NTO. Based on the results of these studies, it is suggested that removal or mitigation of a buildup of these materials may decrease the incidence of these high-energy, potentially damaging events.

1996-01-01

173

The effect of lipid peroxidation products on reactive oxygen species formation and nitric oxide production in lipopolysaccharide-stimulated RAW 264.7 macrophages.  

PubMed

Lipid peroxidation induced by oxidants leads to the formation of highly reactive metabolites. These can affect various immune functions, including reactive oxygen species (ROS) and nitric oxide (NO) production. The aim of the present study was to investigate the effects of lipid peroxidation products (LPPs) - acrolein, 4-hydroxynonenal, and malondialdehyde - on ROS and NO production in RAW 264.7 macrophages and to compare these effects with the cytotoxic properties of LPPs. Macrophages were stimulated with lipopolysaccharide (0.1 ?g/ml) and treated with selected LPPs (concentration range: 0.1-100 ?M). ATP test, luminol-enhanced chemiluminescence, Griess reaction, Western blotting analysis, amperometric and total peroxyl radical-trapping antioxidant parameter assay were used for determining the LPPs cytotoxicity, ROS and NO production, inducible nitric oxide synthase expression, NO scavenging, and antioxidant properties of LPPs, respectively. Our study shows that the cytotoxic action of acrolein and 4-hydroxynonenal works in a dose- and time-dependent manner. Further, our results imply that acrolein, 4-hydroxynonenal, and malondialdehyde can inhibit, to a different degree, ROS and NO production in stimulated macrophages, partially independently of their toxic effect. Also, changes in enzymatic pathways (especially NADPH-oxidase and nitric oxide synthase inhibition) and NO scavenging properties are included in the downregulation of reactive species formation. PMID:20940037

Ambrozova, Gabriela; Pekarova, Michaela; Lojek, Antonin

2011-02-01

174

Reaction of acetaldehyde cations with water: The effects of CH3CHO+ vibrational mode and impact parameter on reactivity and product branching  

NASA Astrophysics Data System (ADS)

Scattering of mode-selectively excited acetaldehyde cations from D2O was studied in a guided ion beam instrument. The effects of reactant vibrational state and collision energy on reactivity, product branching, and product ion recoil velocity distributions were measured. Ab initio calculations were performed to help understand the reaction coordinate. The dominant reaction is H/D exchange, which occurs in about 40% of low energy collisions, dropping to just a few percent at high energies. H/D exchange is also inhibited by CH3CHO+ vibration, but with a smaller effect than the equivalent amount of collision energy. H/D exchange is mediated by a long-lived complex, and several candidates are identified. The other low energy channel corresponds to methyl elimination from the collision complex. This channel is the most energetically favorable, but is only a few percent efficient, even at low energies, and is negligible at high energies. Methyl elimination is strongly suppressed by both collision energy and vibration, and the vibrational effects are nonmode specific. The most interesting channel is proton transfer (PT), which occurs by a direct mechanism at all collision energies. At low energies, PT occurs only in small impact parameter collisions, while at high energies, PT occurs primarily for large impact parameters, and is suppressed for small impact parameters. PT also shows strongly mode-specific dependence on CH3CHO+ vibrational state.

Kim, Ho-Tae; Liu, Jianbo; Anderson, Scott L.

2001-07-01

175

The production of reactive oxygen species by irradiated camphorquinone-related photosensitizers and their effect on cytotoxicity  

Microsoft Academic Search

Camphorquinone (CQ) is widely used as an initiator in modern light-cured resin systems but there are few reports about its effects on living cells. To clarify the mechanism of photosensitizer-induced cytotoxicity, the production of initiator radicals and subsequent reactive oxygen species (ROS) by CQ, benzil (BZ), benzophenone (BP), 9-fluorenone (9-F) in the presence of the reducing agent (2-dimethylaminoethyl methacrylate or

T Atsumi; I Iwakura; S Fujisawa; T Ueha

2001-01-01

176

A High Calcium-Phosphate Product Is Associated with High C-Reactive Protein Concentrations in Hemodialysis Patients  

Microsoft Academic Search

Background: An elevated Ca×PO4 product and C-reactive protein (CRP) have been associated with coronary artery calcification and increased cardiovascular mortality in hemodialysis (HD) patients. However, it has not been defined, so far, whether and how both parameters are related to each other. For this reason we have evaluated in a cross-sectional and in an interventional study the possible correlation between

Ezio Movilli; Annalisa Feliciani; Corrado Camerini; Giulio Brunori; Roberto Zubani; Francesco Scolari; Giovanni Parrinello; Giovanni C. Cancarini

2005-01-01

177

Honokiol protects rat brain from focal cerebral ischemia–reperfusion injury by inhibiting neutrophil infiltration and reactive oxygen species production  

Microsoft Academic Search

We have previously shown that honokiol, an active component of Magnolia officinalis, displayed protective effect against focal cerebral ischemia–reperfusion (FCI\\/R) injury in rats. Production of reactive oxygen species (ROS) and infiltration of neutrophils to injured tissue play deleterious roles during cerebral ischemia. To study the mechanism(s) in mediating neuroprotective effect of honokiol, FCI\\/R-induced neutrophil infiltration and lipid peroxidation in brain

Kuo-Tong Liou; Yuh-Chiang Shen; Chieh-Fu Chen; Cheng-Ming Tsao; Shen-Kou Tsai

2003-01-01

178

Dihydroorotate dehydrogenase is required for N-(4-hydroxyphenyl)retinamide-induced reactive oxygen species production and apoptosis  

Microsoft Academic Search

The synthetic retinoid N-(4-hydroxyphenyl)retinamide (4HPR) exhibits anticancer activity in vivo and triggers apoptosis in transformed cells in vitro. Thus, apoptosis induction is acknowledged as a mechanistic underpinning for 4HPR's cancer preventive and therapeutic effects. Apoptosis induction by 4HPR is routinely preceded by and dependent on the production of reactive oxygen species (ROS) in transformed cells. Very little evidence exists, outside

Numsen Hail Jr.; Ping Chen; Jadwiga J. Kepa; Colin Shearn

2010-01-01

179

Pulmonary Surfactant Protein A Inhibits Macrophage Reactive Oxygen Intermediate Production in Response to Stimuli by Reducing NADPH Oxidase Activity1  

Microsoft Academic Search

Alveolar macrophages are important host defense cells in the human lung that continuously phagocytose environmental and infectious particles that invade the alveolar space. Alveolar macrophages are prototypical alternatively activated macrophages, with up-regulated innate immune receptor expression, down-regulated costimulatory molecule expression, and limited production of reactive oxygen intermediates (ROI) in response to stimuli. Surfactant protein A (SP-A) is an abundant protein

Joy E. Crowther; Vijay Kumar Kutala; Periannan Kuppusamy; J. Scott Ferguson; Alison A. Beharka; Jay L. Zweier; Francis X. McCormack; Larry S. Schlesinger

180

Homocysteine-Induced Endothelin1 Release Is Dependent on Hyperglycaemia and Reactive Oxygen Species Production in Bovine Aortic Endothelial Cells  

Microsoft Academic Search

Background: Elevated plasma homocysteine (Hcy) is a risk factor for coronary disease. The objective of this study was to investigate whether Hcy either alone or in high glucose conditions induces endothelin-1 (ET-1) synthesis via the production of reactive oxygen species (ROS). Methods: Bovine aortic endothelial cells were grown in high (25 mmol\\/l) and low (5 mmol\\/l) glucose medium. Results: In

Amarjit S. Sethi; Delphine M. Lees; Julie A. Douthwaite; Anne B. Dawnay; Roger Corder

2006-01-01

181

Solid Oxygen: Ultra-Cold Neutron Production from Magnetic Excitations as Illuminated by Inelastic Neutron Scattering  

NASA Astrophysics Data System (ADS)

Ultra Cold Neutrons (UCN, E˜100 neV) are supremely useful in the study of the weak interaction physics and provide a sensitive platform for theories beyond the standard model via measurement of the neutron electric dipole moment. UCN are produced from a cold neutron beam via excitation of collective modes in materials such as solid deuterium and liquid helium. Unfortunately, UCN sources are limited by low intensity. This provides an interesting point of collaboration between condensed matter and nuclear physics as we attempt to develop stronger sources. We have investigated the magnetic phases of solid oxygen as a potential UCN source by measuring UCN production from solid oxygen directly. Complete understanding of the results was elusive until we conducted a recent series of inelastic neutron studies scattering using the Disc Chopper Spectrometer time-of-flight instrument at NIST. Of particular interest is the high efficiency of magnetic inelastic scattering for UCN production, and the powerful influence of the spin ordering transition.

Lavelle, Christopher M.; Liu, Chen-Yu; McChesney, Patrick M.; Salvat, Dan J.; Manus, Greg; Makela, Mark; Saunders, Andy; Couture, Aaron; Morris, Chris; Young, Albert; Brown, Craig M.

2010-03-01

182

Atomic mass dependence of hadron production in semi-inclusive deep inelastic lepton-nucleus scattering  

NASA Astrophysics Data System (ADS)

Hadron production in lepton-nucleus deep inelastic scattering is studied in a quark energy loss model. The leading-order computations for hadron multiplicity ratios are presented and compared with the selected HERMES pions production data with the quark hadronization occurring outside the nucleus by means of the hadron formation time. It is found that the obtained energy loss per unit length is 0.440±0.013 GeV/fm for an outgoing quark by the global fit. It is confirmed that the atomic mass number dependence of hadron attenuation is theoretically and experimentally in good agreement with the A2/3 power law for quark hadronization occurring outside the nucleus.

Song, Li-Hua; Liu, Na; Duan, Chun-Gui

2013-08-01

183

An index for quantifying the aerobic reactivity of municipal solid wastes and derived waste products  

Microsoft Academic Search

The organic matter contained in municipal solid waste (MSW) and in the MSW fractions obtained by mechanical separation has strong environmental impact when the waste is used as landfill. This is partly due to the biological activity that occurs under anaerobic conditions. Negative effects on the environment include unpleasant odors, biogas, leachate and biomass self-heating. Measuring the biological reactivity of

Barbara Scaglia; Fabrizio Adani

2008-01-01

184

Vascular Smooth Muscle Modulates Endothelial Control of Vasoreactivity via Reactive Oxygen Species Production through Myoendothelial Communications  

Microsoft Academic Search

BackgroundEndothelial control of vascular smooth muscle plays a major role in the resulting vasoreactivity implicated in physiological or pathological circulatory processes. However, a comprehensive understanding of endothelial (EC)\\/smooth muscle cells (SMC) crosstalk is far from complete. Here, we have examined the role of gap junctions and reactive oxygen species (ROS) in this crosstalk and we demonstrate an active contribution of

Marie Billaud; Roger Marthan; Jean-Pierre Savineau; Christelle Guibert; Neeraj Vij

2009-01-01

185

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

186

Induction of microglial reactive oxygen species production by the organochlorinated pesticide dieldrin  

Microsoft Academic Search

Exposure to pesticides has been speculated to contribute to the development of sporadic Parkinson's disease (PD) characterized by a progressive degeneration of the nigrostriatal dopaminergic pathway. Activation of brain microglia that produce various neurotoxic factors including cytokines and reactive oxygen species (ROS) has been increasingly associated with dopaminergic neurodegeneration induced by various toxicants. Dieldrin, a highly persistent organochlorinated pesticide found

Haoyu Mao; Xi Fang; Katon M. Floyd; Jeanette E. Polcz; Ping Zhang; Bin Liu

2007-01-01

187

Controlling Tumor Growth by Modulating Endogenous Production of Reactive Oxygen Species  

Microsoft Academic Search

Paradoxically, reactive oxygen species (ROS) can promote normal cellular proliferation and carcinogenesis, and can also induce apoptosis of tumor cells. In this report, we study the contribution of ROS to various cellular signals depending on the nature and the level of ROS produced. In nontransformed NIH 3T3 cells, ROS are at low levels and originate from NADPH oxidase. Hydrogen peroxide

Alexis Laurent; Carole Nicco; Christiane Chereau; Claire Goulvestre; Jerome Alexandre; Arnaud Alves; Eva Levy; Francois Goldwasser; Yves Panis; Olivier Soubrane; Bernard Weill; Frederic Batteux

2005-01-01

188

Direct electrochemical characterization of superoxide anion production and its reactivity toward nitric oxide in solution  

Microsoft Academic Search

We report in this study, and for the first time the direct and simultaneous electrochemical measurements of both nitric oxide and superoxide anion evolution and reactivity in solution. For this purpose, we have combined the use of two electrodes: a previously developed NO-sensor for the amperometric determination of NO and a carbon microelectrode for the amperometric detection of superoxide anion.

Christelle Privat; Stéphane Trevin; Fethi Bedioui; Jacques Devynck

1997-01-01

189

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

190

In situ lipase-catalyzed reactive extraction of oilseeds with short-chained dialkyl carbonates for biodiesel production.  

PubMed

Dimethyl/diethyl carbonate was adopted as extraction solvent and transesterification reagent at the same time for in situ lipase-catalyzed reactive extraction of oilseeds for biodiesel production in this work. Fatty acid methyl esters and ethyl esters were respectively obtained with higher yields than those achieved by conventional two-step extraction/transesterification. The augment ranged from 15.7% to 31.7%. The key parameters such as solvent/seed ratio and water content were further investigated to find their effects on the in situ reactive extraction. The highest yields of Pistacia chinensis Bunge methyl ester, P. chinensis Bunge ethyl ester, Jatropha curcas L methyl ester and J. curcas L ethyl ester could attain 89.6%, 90.7%, 95.9% and 94.5%, respectively under the optimized conditions. PMID:19615896

Su, Erzheng; You, Pengyong; Wei, Dongzhi

2009-12-01

191

Mitochondrial dysfunction promotes breast cancer cell migration and invasion through HIF1? accumulation via increased production of reactive oxygen species.  

PubMed

Although mitochondrial dysfunction has been observed in various types of human cancer cells, the molecular mechanism underlying mitochondrial dysfunction mediated tumorigenesis remains largely elusive. To further explore the function of mitochondria and their involvement in the pathogenic mechanisms of cancer development, mitochondrial dysfunction clones of breast cancer cells were generated by rotenone treatment, a specific inhibitor of mitochondrial electron transport complex I. These clones were verified by mitochondrial respiratory defect measurement. Moreover, those clones exhibited increased reactive oxygen species (ROS), and showed higher migration and invasive behaviors compared with their parental cells. Furthermore, antioxidant N-acetyl cysteine, PEG-catalase, and mito-TEMPO effectively inhibited cell migration and invasion in these clones. Notably, ROS regulated malignant cellular behavior was in part mediated through upregulation of hypoxia-inducible factor-1 ? and vascular endothelial growth factor. Our results suggest that mitochondrial dysfunction promotes cancer cell motility partly through HIF1? accumulation mediated via increased production of reactive oxygen species. PMID:23922721

Ma, Jia; Zhang, Qing; Chen, Sulian; Fang, Binbin; Yang, Qingling; Chen, Changjie; Miele, Lucio; Sarkar, Fazlul H; Xia, Jun; Wang, Zhiwei

2013-01-01

192

Mitochondrial Dysfunction Promotes Breast Cancer Cell Migration and Invasion through HIF1? Accumulation via Increased Production of Reactive Oxygen Species  

PubMed Central

Although mitochondrial dysfunction has been observed in various types of human cancer cells, the molecular mechanism underlying mitochondrial dysfunction mediated tumorigenesis remains largely elusive. To further explore the function of mitochondria and their involvement in the pathogenic mechanisms of cancer development, mitochondrial dysfunction clones of breast cancer cells were generated by rotenone treatment, a specific inhibitor of mitochondrial electron transport complex I. These clones were verified by mitochondrial respiratory defect measurement. Moreover, those clones exhibited increased reactive oxygen species (ROS), and showed higher migration and invasive behaviors compared with their parental cells. Furthermore, antioxidant N-acetyl cysteine, PEG-catalase, and mito-TEMPO effectively inhibited cell migration and invasion in these clones. Notably, ROS regulated malignant cellular behavior was in part mediated through upregulation of hypoxia-inducible factor-1 ? and vascular endothelial growth factor. Our results suggest that mitochondrial dysfunction promotes cancer cell motility partly through HIF1? accumulation mediated via increased production of reactive oxygen species.

Chen, Sulian; Fang, Binbin; Yang, Qingling; Chen, Changjie; Miele, Lucio; Sarkar, Fazlul H.; Xia, Jun; Wang, Zhiwei

2013-01-01

193

Degradation of reactive dyes in wastewater from the textile industry by ozone: analysis of the products by accurate masses.  

PubMed

The present work describes the use of ozone to degrade selected reactive dyes from the textile industry and the analysis of the resulting complex mixture by liquid chromatography/mass spectrometry (LC-MS). To allow certain identification of the substances detected in the wastewater, the original dyes were also investigated either separately or in a synthetic mixture of three dyes (trichromie). Since the reactive dyes are hydrolyzed during the dyeing process, procedures for the hydrolysis were worked out first for the individual dyes. The ozonated solutions were concentrated by solid-phase extraction, which separated very polar or ionic substances from moderately polar degradation products. The latter, which are the primary degradation products, were investigated by liquid chromatography/mass spectrometry with a tandem quadrupole time-of-flight mass analyzer. Accurate masses, which in most cases could be determined with a deviation of products in the same run. With retention times, mass spectra, accurate masses, UV-vis spectra and, of course, knowledge of the structures of the original dyes, plausible structures could be proposed for most of the components of the moderately polar fraction. These structures were confirmed by 1H NMR in cases where it was practical to isolate the degradation products by preparative HPLC. PMID:19110293

Constapel, Marc; Schellenträger, Marc; Marzinkowski, Joachim Michael; Gäb, Siegmar

2009-02-01

194

Involvement of Cytochrome P450 1A in the Toxicity of Aryl Hydrocarbon Receptor Agonists: Alteration of Arachidonic Acid Metabolism and Production of Reactive Oxygen Species.  

National Technical Information Service (NTIS)

Two cytochrome P4501A-dependent mechanisms of aryl hydrocarbon receptor (AhR) agonist toxicity were examined in the marine teleost scup (Stenotomus chrysops), alteration of arachidonic acid (AA) metabolism and production of reactive oxygen species (ROS). ...

J. J. Schlezinger

1998-01-01

195

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...

196

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

197

Contributions of hyperon-hyperon scattering to subthreshold cascade production in heavy ion collisions  

NASA Astrophysics Data System (ADS)

Using a gauged flavor SU(3)-invariant hadronic Lagrangian, we calculate the cross sections for the strangeness-exchange reactions YY?N? (Y=?,?) in the Born approximation. These cross sections are then used in the relativistic Vlasov-Uehling-Uhlenbeck transport model to study ? production in Ar+KCl collisions at incident energy of 1.76A GeV and impact parameter b=3.5 fm. We find that including the contributions of hyperon-hyperon scattering channels strongly enhances the yield of ?, leading to the abundance ratio ?-/(?+?0)=3.38×10-3, which is essentially consistent with the recently measured value of (5.6±1.2-1.7+1.8)×10-3 by the HADES Collaboration at GSI.

Li, Feng; Chen, Lie-Wen; Ko, Che Ming; Lee, Su Houng

2012-06-01

198

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

199

Mechanism of pion production in {alpha}p scattering at 1 GeV/nucleon  

SciTech Connect

An analysis of the experimental data on one-pion and two-pion production in the p({alpha}, {alpha} Prime )X reaction studied in a semi-exclusive experiment at an energy of E{sub {alpha}} = 4.2 GeV has been performed. The obtained results demonstrate that the inelastic {alpha}-particle scattering on the proton at the energy of the experiment proceeds either through excitation and decay of the {Delta} resonance in the projectile {alpha} particle, or through excitation in the target proton of the Roper resonance, which decays into a nucleon and a pion, or a nucleon and a {sigma} meson-a system of two pions in the isospin I = 0, S-wave state.

Alkhazov, G. D.; Prokofiev, A. N., E-mail: prokan@pnpi.spb.ru; Smirnov, I. B. [Petersburg Nuclear Physics Institute (Russian Federation); Strokovsky, E. A. [Joint Institute for Nuclear Research (Russian Federation)

2012-09-15

200

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

NASA Astrophysics Data System (ADS)

Measurements of K0 meson and ? baryon production in deep-inelastic positron-proton scattering (DIS) are presented in the kinematic range 10 < Q2 < 70 GeV 2 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 xF spectra, where xF is the fractional longitudinal momentum in the hadronic centre-of-mass frame, are made with results from electron-positron annihilation. The xF spectra and the K0 "seagull" plot are compared with previous DIS results. The mean K0 and ? multiplicities are studied as a function of the centre-of-mass energy W and are observed to be consistent with a logarithmic increase with W when compared with previous measurements. A comparison of strangeness production in diffractive and non-diffractive DIS is made. An upper limit of 0.9 nb, at the 95% confidence level, is placed on the cross section for QCD instanton induced events.

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

1996-02-01

201

Pivotal role of reactive oxygen species in differential regulation of lipopolysaccharide-induced prostaglandins production in macrophages.  

PubMed

Gram-negative bacterial endotoxin lipopolysaccharide (LPS) triggers the production of inflammatory cytokines, reactive oxygen species (ROS), and prostaglandins (PGs) by pulmonary macrophages. Here, we investigated if ROS influenced PGs production in response to LPS treatment in mouse bone marrow-derived macrophages (BMDM). We observed that pretreatment of BMDM with two structurally unrelated ROS scavengers, MnTMPyP and EUK-134, not only prevented LPS-induced ROS accumulation, but also attenuated the LPS-induced PGD(2), but not PGE(2), production. Conversely LPS-induced PGD(2), but not PGE(2), production, was potentiated with the cotreatment of BMDM with H(2)O(2). These data suggest that ROS differentially regulate PGD(2) and PGE(2) production in BMDM. In addition, selective inhibition of the ROS generator NADPH oxidase (NOX) using either pharmacologic inhibitors or its p47(phox) subunit deficient mouse BMDM also attenuated LPS-induced PGD(2), but not PGE(2) production, suggesting the critical role of NOX-generated ROS in LPS-induced PGD(2) production in BMDM. We further found that both hematopoietic PGD synthase (H-PGDS) siRNA and its inhibitor HQL-79, but not lipocalin PGDS (L-PGDS) siRNA and its inhibitor AT-56, significantly attenuated LPS-induced PGD(2) production, suggesting that H-PGDS, but not L-PGDS, mediates LPS-induced PGD(2) production in BMDM. Furthermore, data from our in vitro cell-free enzymatic studies showed that coincubation of the recombinant H-PGDS with either MnTMPyP, EUK-134, or catalase significantly decreased PGD(2) production, whereas coincubation with H(2)O(2) significantly increased PGD(2) production. Taken together, our results show that LPS-induced NOX-generated ROS production differentially and specifically regulates the H-PGDS-mediated production of PGD(2), but not PGE(2), in mouse BMDM. PMID:23071105

Zhao, Guiqing; Yu, Rui; Deng, Jing; Zhao, Qiong; Li, Yongchao; Joo, Myungsoo; van Breemen, Richard B; Christman, John W; Xiao, Lei

2013-01-01

202

Origin of cadmium-induced reactive oxygen species production: mitochondrial electron transfer versus plasma membrane NADPH oxidase.  

PubMed

* Cadmium (Cd(2+)) is an environmental pollutant that causes increased reactive oxygen species (ROS) production. To determine the site of ROS production, the effect of Cd(2+) on ROS production was studied in isolated soybean (Glycine max) plasma membranes, potato (Solanum tuberosum) tuber mitochondria and roots of intact seedlings of soybean or cucumber (Cucumis sativus). * The effects of Cd(2+) on the kinetics of superoxide (O2*-), hydrogen peroxide (H(2)O(2)) and hydroxyl radical ((*OH) generation were followed using absorption, fluorescence and spin-trapping electron paramagnetic resonance spectroscopy. * In isolated plasma membranes, Cd(2+) inhibited O2*- production. This inhibition was reversed by calcium (Ca(2+)) and magnesium (Mg(2+)). In isolated mitochondria, Cd(2+) increased and H(2)O(2) production. In intact roots, Cd(2+) stimulated H(2)O(2) production whereas it inhibited O2*- and (*)OH production in a Ca(2+)-reversible manner. * Cd(2+) can be used to distinguish between ROS originating from mitochondria and from the plasma membrane. This is achieved by measuring different ROS individually. The immediate (production in the mitochondrial electron transfer chain and inhibition of NADPH oxidase activity in the plasma membrane. PMID:18537884

Heyno, Eiri; Klose, Cornelia; Krieger-Liszkay, Anja

2008-01-01

203

Selective production of reactive and nonreactive oxygen atoms on Pd(001) by rotationally aligned oxygen molecules.  

PubMed

Sticking together: The occupation of different sites by oxygen atoms that are produced by the dissociation of O(2) on Pd(100) is determined by the initial rotational alignment of the parent molecules. The atom locations are characterized by different chemical reactivities in the reaction with CO to form CO(2) (see picture), which are followed by synchrotron radiation (SR) experiments with a supersonic molecular beam (SMB). PMID:19479918

Vattuone, Luca; Gerbi, Andrea; Cappelletti, David; Pirani, Fernando; Gunnella, Roberto; Savio, Letizia; Rocca, Mario

2009-01-01

204

Production and characterization of antibodies cross-reactive with major aflatoxins  

Microsoft Academic Search

Summary Antibodies cross-reactive with 4 major aflatoxins were demonstrated three weeks after immunization of rabbits with an immunogen which was prepared by conjugating aflatoxin B3 to bovine serum albumin. Aflatoxin B3 was first converted to its hemisuccinate before conjugation to the protein. Tritiated aflatoxin B1 (AFB1) was used as the marker ligand both for antibody titer determination as well as

G. Zhang; F. S. Chu

1989-01-01

205

Production and characterization of monoclonal antibodies cross?reactive with major aflatoxins  

Microsoft Academic Search

Monoclonal antibodies cross?reactive with four major aflatoxins (AFs) were produced by fusion of P3\\/NS?1\\/1?AG4–1 murine myeloma cells with spleen cells isolated from a BALB\\/c mouse that had been immunized with aflatoxin B3?hemisuccinate conjugated to bovine serum albumin. Six stable clones were obtained. Isotyping by enzyme?linked immunosorbent assay (ELISA) revealed that the antibodies produced by all but two of the clones

Susan L. Hefle; Fun Sun Chu

1990-01-01

206

Enhanced pilot-scale fed-batch L-phenylalanine production with recombinant Escherichia coli by fully integrated reactive extraction.  

PubMed

A fully integrated process for the microbial production and recovery of the aromatic amino acid L-phenylalanine is presented. Using a recombinant L-tyrosine (L-Tyr) auxotrophic Escherichia coli production strain, a fed-batch fermentation process was developed in a 20-l-scale bioreactor. Concentrations of glucose and L-Tyr were closed-loop-controlled in a fed-batch process. After achieving final L-phenylalanine (L-Phe) titres >30 g/l the process strategy was scaled up to 300-l pilot scale. In technical scale fermentation L-phenylalanine was continuously recovered via a fully integrated reactive extraction system achieving a maximum extraction rate of 110 g/h (final purity >99%). It was thus possible to increase L-Phe/glucose selectivity from 15 mol% without to 20.3 mol% with integrated product separation. PMID:14505019

Gerigk, M R; Maass, D; Kreutzer, A; Sprenger, G; Bongaerts, J; Wubbolts, M; Takors, R

2002-04-01

207

NADPH oxidase-mediated reactive oxygen species production: subcellular localization and reassessment of its role in plant defense.  

PubMed

Chemiluminescence detection of reactive oxygen species (ROS) triggered in tobacco BY-2 cells by the fungal elicitor cryptogein was previously demonstrated to be abolished in cells transformed with an antisense construct of the plasma membrane NADPH oxidase, NtrbohD. Here, using electron microscopy, it has been confirmed that the first hydrogen peroxide production occurring a few minutes after challenge of tobacco cells with cryptogein is plasma membrane located and NtrbohD mediated. Furthermore, the presence of NtrbohD in detergent-resistant membrane fractions could be associated with the presence of NtrbohD-mediated hydrogen peroxide patches along the plasma membrane. Comparison of the subcellular localization of ROS in wild-type tobacco and in plants transformed with antisense constructs of NtrbohD revealed that this enzyme is also responsible for the hydrogen peroxide production occurring at the plasma membrane after infiltration of tobacco leaves with cryptogein. Finally, the reactivity of wild-type and transformed plants to the elicitor and their resistance against the pathogenic oomycete Phytophthora parasitica were examined. NtrbohD-mediated hydrogen peroxide production does not seem determinant for either hypersensitive response development or the establishment of acquired resistance but it is most likely involved in the signaling pathways associated with the protection of the plant cell. PMID:19522569

Lherminier, Jeannine; Elmayan, Taline; Fromentin, Jérôme; Elaraqui, Khadija Tantaoui; Vesa, Simona; Morel, Johanne; Verrier, Jean-Louis; Cailleteau, Bernard; Blein, Jean-Pierre; Simon-Plas, Françoise

2009-07-01

208

Control of reactive oxygen species (ROS) production through histidine kinases in Aspergillus nidulans under different growth conditions?  

PubMed Central

Sensor histidine kinases (HKs) are important factors that control cellular growth in response to environmental conditions. The expression of 15 HKs from Aspergillus nidulans was analyzed by quantitative real-time PCR under vegetative, asexual, and sexual growth conditions. Most HKs were highly expressed during asexual growth. All HK gene-disrupted strains produced reactive oxygen species (ROS). Three HKs are involved in the control of ROS: HysA was the most abundant under the restricted oxygen condition, NikA is involved in fungicide sensing, and FphA inhibits sexual development in response to red light. Phosphotransfer signal transduction via HysA is essential for ROS production control.

Hayashi, Saki; Yoshioka, Megumi; Matsui, Tetsuji; Kojima, Kensuke; Kato, Masashi; Kanamaru, Kyoko; Kobayashi, Tetsuo

2014-01-01

209

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

NASA Astrophysics Data System (ADS)

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 for 10 GeV2?Q2?100 GeV2 and 0.01? y?0.7 of? (ep to ecbar cX) = (17.4 ± 1.6 ± 1.7 ± 1.4) nb is derived. A first measurement of the charm contributionF_2^{cbar c} (x,Q^2 ) to the proton structure function for Bjorken x between 8·10-4 and 8·10-3 is presented. In this kinematic range a ratioF_2^{cbar c} /F_2 = 0.237 ± 0.021 ± 0.041 is observed.

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

1996-12-01

210

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

2008-02-01

211

Chemical Characterization and Reactivity Testing of Fuel-Oxidizer Reaction Product (Test Report).  

National Technical Information Service (NTIS)

The product of incomplete reaction of monomethylhydrazine (MMH) and nitrogen tetroxide (NTO) propellants, or fuel-oxidizer reaction product (FORP), has been hypothesized as a contributory cause of an anomaly which occurred in the chamber pressure (PC) tra...

1996-01-01

212

Neutrons Scattering and Gamma-Ray Production Cross Sections for N, O, Al, Si, Ca and Fe.  

National Technical Information Service (NTIS)

Measurements of neutron elastic and inelastic scattering and gamma-ray production have been made on several elements with 9.0 and 11.0 MeV incident neutrons. Differential cross sections for N, O, Al, Si, Ca, and Fe are presented and integral cross section...

D. O. Nellis P. S. Buchanan T. C. Martin W. E. Tucker G. H. Williams

1972-01-01

213

Production of Ultra-Cold Neutrons Using Doppler-Shifted Bragg Scattering and an Intense Pulsed Neutron Spallation Source.  

National Technical Information Service (NTIS)

An analytic and a computer generated simulation of the production of Ultra-Cold Neutrons (UCN) is presented using Bragg scattering from a moving crystal to Doppler shift higher velocity neutrons into the UCN region. The calculation was carried out with a ...

T. W. Dombeck J. W. Lynn

1979-01-01

214

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

215

Optimizing Pulse Waveforms in Plasma Jets for Reactive Oxygen Species (ROS) Production  

NASA Astrophysics Data System (ADS)

Reactive oxygen species (ROS) are desired in numerous applications from the destruction of harmful proteins and bacteria for sterilization in the medical field to taking advantage of the metastable characteristics of O2(^1?) to transfer energy to other species. Advances in atmospheric pressure plasma jets in recent years show the possibility of using this application as a source of reactive oxygen species. In this paper, we report on results from a computational investigation of atmospheric pressure plasma jets in a dielectric barrier discharge (DBD) configuration. The computer model used in this study, nonPDPSIM, solves transport equations for charged and neutral species, Poisson's equation for the electric potential, the electron energy conservation equation for the electron temperature, and Navier-Stokes equations for the neutral gas flow. A Monte Carlo simulation is used to track sheath accelerated secondary electrons emitted from surfaces and the energy of ions incident onto surfaces. Rate coefficients and transport coefficients for the bulk plasma are obtained from local solutions of Boltzmann's equation for the electron energy distribution. Radiation transport is addressed using a Green's function approach. Various waveforms for the voltage source were examined in analogy to spiker-sustainer systems used at lower gas pressures.

Norberg, Seth; Babaeva, Natalia Yu.; Kushner, Mark J.

2012-10-01

216

Production and properties of p-n junctions in reactively sputtered ZnO  

NASA Astrophysics Data System (ADS)

In order to develop electroluminescent and laser devices based on the ultraviolet exciton emission of ZnO, it will be important to fabricate good p-n junctions. As-grown ZnO is normally n-type because of intrinsic donor defects such as oxygen vacancies and zinc interstitials, or unintended hydrogen. Making p-type ZnO has been more difficult, possibly due to self-compensation by easily formed donor defects. In this work, we demonstrate that reactively sputtered, annealed ZnO films can be changed from n-type to moderate p-type by adjusting the oxygen/argon ratio in the sputtering plasma. We report the properties of p-n homojunctions fabricated in this way, and characterize transport in the films by the Hall measurements. Ohmic contacts were formed by deposition of Au/Al films. Our finding of p-type conductivity in apparently intrinsic ZnO formed by reactive sputtering is not inconsistent with calculated defect formation enthalpies if account is taken of the higher chemical potential of the dissociated oxygen reservoir represented by the sputter plasma, compared to the molecular oxygen reservoir assumed in the calculation of formation enthalpies. If hydrogen turns out to be the main compensating donor, the role of oxygen pressure in controlling incorporation of background hydrogen during sputtering may also be implicated.

Tüzemen, S.; Xiong, Gang; Wilkinson, John; Mischuck, Brian; Ucer, K. B.; Williams, R. T.

2001-12-01

217

Krebs cycle intermediates modulate thiobarbituric acid reactive species (TBARS) production in rat brain in vitro.  

PubMed

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 (1.91) > > malate (12.74). alpha-Ketoglutarate caused an increase in TBARS production without modifying the QA-induced TBARS production. Cyanide (CN-) did not modify the basal or QA-induced TBARS production; however, CN- abolished the antioxidant effects of succinate. QA-induced TBARS production was enhanced by iron ions, and abolished by desferrioxamine (DFO). The intermediates used in this study, except for alpha-ketoglutarate, prevented iron-induced TBARS production. Oxaloacetate, citrate, alpha-ketoglutarate and malate, but no succinate and QA, exhibited significantly iron-chelating properties. Only alpha-ketoglutarate and oxaloacetate protected against hydrogen peroxide-induced deoxyribose degradation, while succinate and malate showed a modest effect against Fe2+/H2O2-induced deoxyribose degradation. Using heat-treated preparations citrate, malate and oxaloacetate protected against basal or QA-induced TBARS production, whereas alpha-ketoglutarate induced TBARS production. Succinate did not offer protection against basal or QA-induced TBARS production. These results suggest that oxaloacetate, malate, succinate, and citrate are effective antioxidants against basal and iron or QA-induced TBARS production, while alpha-ketoglutarate stimulates TBARS production. The mechanism through which Krebs cycle intermediates offer protection against TBARS production is distinct depending on the intermediate used. Thus, under pathological conditions such as ischemia, where citrate concentrations vary it can assume an important role as a modulator of oxidative stress associated with such situations. PMID:15895826

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

2005-02-01

218

Final State Scattering in Z Production via the Quark-Gluon Interaction  

Microsoft Academic Search

Analytical calculation of photon scattering between final state quark and a final state lepton in the process q gRightarrow q | q qRightarrow Z^0 qRightarrow l^{+} l^{-} q. Result is found as a ratio to the same process without final state scattering. Motivation for the calculation is as a first step towards calculating photon scattering between final state leptons and

Thomas Mitchel Ewing

1989-01-01

219

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

SciTech Connect

Monte Carlo codes have been developed to simulate gamma-ray scattering and production in the atmosphere. The scattering code simulates interactions of low-energy gamma rays (20 to several hundred keV) from an astronomical point source in the atmosphere; a modified code also simulates scattering in a spacecraft. Four incident spectra, typical of gamma-ray bursts, solar flares, and the Crab pulsar, and 511 keV line radiation have been studied. These simulations are consistent with observations of solar flare radiation scattered from the atmosphere. The production code simulates the interactions of cosmic rays which produce high-energy (above 10 MeV) photons and electrons. It has been used to calculate gamma-ray and electron albedo intensities at Palestine, Texas and at the equator; the results agree with observations in most respects. With minor modifications this code can be used to calculate intensities of other high-energy particles. Both codes are fully three-dimensional, incorporating a curved atmosphere; the production code also incorporates the variation with both zenith and azimuth of the incident cosmic-ray intensity due to geomagnetic effects. These effects are clearly reflected in the calculated albedo by intensity contrasts between the horizon and nadir, and between the east and west horizons.

Morris, D.J. (Space Science Center, University of New Hampshire, Durham, N.H. 03824 (US))

1989-05-15

220

Reactive oxygen production against malaria--a potential cancer risk factor.  

PubMed

In response to malaria infection, phagocytes, such as macro-phages and neutrophils, produce superoxide and thence the other reactive oxygen species (ROS) with which to kill the parasites. Excess ROS is normally eliminated by the body's natural scavenger molecules; however, in the event of a vast excess of ROS, as may be the case in acute as well as chronic malaria patients, the natural scavengers may be overwhelmed. We hypothesize that unscavenged ROS in malaria patients causes DNA damage in normal host cells which, if unrepaired or incorrectly repaired, could result in oncogene activation and eventually lead to cancer. An epidemiologic study may be warranted in malaria-endemic regions to investigate the possible relationship between malaria infection and cancer risk. PMID:2377089

Eze, M O; Hunting, D J; Ogan, A U

1990-06-01

221

Single-parton scattering versus double-parton scattering in the production of two cc¯ pairs and charmed meson correlations at the LHC  

NASA Astrophysics Data System (ADS)

We compare results of exact calculations of single-parton scattering (SPS) and double-parton scattering (DPS) for production of cc¯cc¯ and for D meson correlations. The SPS calculations are performed in collinear approximation with exact matrix element for gg?cc¯cc¯ and qq¯?cc¯cc¯ subprocesses. It is shown that the contribution of gluon-gluon subprocess is about factor 50 larger than that for quark-antiquark annihilation. The new results are compared with results of previous calculation with the approximate matrix element for gg?cc¯cc¯ in the high-energy approximation. The cross section for the present exact calculation is bigger only at small invariant masses and small rapidity difference between two c quarks (or two c¯ antiquarks). We compare correlations in rapidities of two c (or two c¯) for DPS and SPS contributions. Finally, we compare our predictions for D mesons with recent results of the LHCb Collaboration for invariant mass, rapidity distance between mesons and dimeson invariant mass. The predicted shapes are similar to the measured ones, however, we still underpredict the experimental cross sections. Our new calculations clearly confirm the dominance of DPS in the production of events with double charm.

van Hameren, Andreas; Maciu?a, Rafa?; Szczurek, Antoni

2014-05-01

222

Chemical pneumonitis and subsequent reactive airways dysfunction syndrome after a single exposure to a household product: a case report  

PubMed Central

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 presentation A 43-year-old Caucasian American man, previously in good health, used a domestic aerosol product called 'Stand N' Seal "Spray-On" Grout Sealer' in an enclosed room in his house. The product contained n-butyl acetate (<5%), propane (10%), isobutane (<5%), C8-C9 petroleum hydrocarbon solvent (80%), a fluoropolymer resin and a solvent. Within a few hours of exposure to the sealant, he developed rapidly progressive shortness of breath and a severe non-productive cough. By the time he reached the emergency room he was severely hypoxic. A diagnosis of chemical pneumonitis was made based on the clinical scenario and the diffuse infiltrates on the computer tomography scan. With supportive therapy, his condition improved and he was discharged from the hospital. However, he continued to have symptoms of intermittent cough and shortness of breath in response to strong odours, fumes, cold air and exertion even after his chest radiograph had normalized. Three months later, bronchial hyper-responsiveness was documented by a methacholine inhalation test and a diagnosis of reactive airways dysfunction syndrome was made. The patient was started on high-dose inhaled steroids and his symptoms improved. The mechanism of toxicity and determination of the exact agent responsible is still under investigation. Conclusion A household product may still prove unsafe to use even after it has gone through vigorous testing and approval processes. Even healthy individuals are susceptible to adverse outcomes after a brief exposure. Extra precautions should be taken when using any chemical product at home.

2009-01-01

223

Strategy to eliminate catalyst hot-spots in the partial oxidation of methane: enhancing its activity for direct hydrogen production by reducing the reactivity of lattice oxygen.  

PubMed

Hydrogen can be produced over Er(2)O(3) in methane oxidation (oxygen/methane = 26). The reactivity of lattice oxygen in the catalyst plays a main role in the conversion of surface hydroxyl species to hydrogen or water. Adding a rare earth element into a catalyst can reduce the reactivity of lattice oxygen, resulting in increased hydrogen production, to eliminate catalyst hot-spots. PMID:20107637

Wen, Cun; Liu, Yi; Guo, Yun; Wang, Yanqin; Lu, Guanzhong

2010-02-14

224

Production of gamma-rays by inverse Compton scattering in jets.  

NASA Astrophysics Data System (ADS)

We discuss a model for the ?-ray production in blazars in which electrons are accelerated rectilinearly in localised regions of the jet, scattering soft radiation from the accretion disk. In our model the jet divides naturally into two zones. In the `radiation dominated zone' (close to the disk), the acceleration of electrons is balanced by inverse Compton losses in the Thomson regime and energy is efficiently transferred into the ?-rays. The ?-ray spectral slope is determined by the electric field profile along the jet. In the `particle dominated zone' (further from the disk) the electron losses are too low to balance acceleration and the electrons are injected into the jet with energies corresponding to the full potential drop in the acceleration region. We suggest that these electrons are then isotropised by the random component of the magnetic field of the jet and cool mainly by synchrotron losses. In the framework of our model we predict further that Galactic black hole candidates might be sources of ?-radiation; in this case, however, we do not expect emission above 10GeV.

Bednarek, W.; Kirk, J. G.; Mastichiadis, A.

1996-12-01

225

TLR3 Activation Augments Matrix Metalloproteinase Production through Reactive Nitrogen Species Generation in Human Lung Fibroblasts.  

PubMed

Viral infection often triggers asthma exacerbation and contributes to airway remodeling. Cell signaling in viral infection is mainly mediated through TLR3. Many mediators are involved in airway remodeling, but matrix metalloproteinases (MMPs) are key players in this process in asthma. However, the role of TLR3 activation in production of MMPs is unknown. In this study, we examined the effects of polyinosinic-polycytidylic acid [poly(I:C)], a ligand for TLR3, on production of MMPs in human lung fibroblasts, with a focus on nitrosative stress in TLR3 modulation of MMP production. After lung fibroblasts were treated with poly(I:C), production of MMP-1, -2, and -9 and inducible NO synthase (iNOS) was assessed. The roles of NF-?B and IFN regulatory factor-3 (IRF-3) in the poly(I:C)-mediated production of MMPs and the responsiveness to poly(I:C) of normal lung fibroblasts and asthmatic lung fibroblasts were also investigated. Poly(I:C) augmented production of MMPs and iNOS in fibroblasts, and an iNOS inhibitor diminished this production of MMPs. Poly(I:C) stimulated translocation of NF-?B and IRF-3 into the nucleus in fibroblasts and inhibition of NF-?B or IRF-3 abrogated the poly(I:C)-induced increase in both iNOS expression and release of MMPs. Poly(I:C)-induced production of iNOS and MMPs was greater in asthmatic fibroblasts than in normal fibroblasts. We conclude that viral infection may induce nitrosative stress and subsequent MMP production via NF-?B- and IRF-3-dependent pathways, thus potentiating viral-induced airway remodeling in asthmatic airways. PMID:24760149

Ichikawa, Tomohiro; Sugiura, Hisatoshi; Koarai, Akira; Minakata, Yoshiaki; Kikuchi, Takashi; Morishita, Yukiko; Oka, Asako; Kanai, Kuninobu; Kawabata, Hiroki; Hiramatsu, Masataka; Akamatsu, Keiichiro; Hirano, Tsunahiko; Nakanishi, Masanori; Matsunaga, Kazuto; Yamamoto, Nobuyuki; Ichinose, Masakazu

2014-06-01

226

Amyloid-?-induced reactive oxygen species production and priming are differentially regulated by ion channels in microglia.  

PubMed

Production of reactive oxygen species (ROS) by microglial cells and subsequent oxidative stress are strongly implicated in the pathogenesis of Alzheimer's disease. Although it is recognized that amyloid-? (A?) plays a major role in inducing and regulating microglial ROS production in Alzheimer's disease, to date little is known about cellular mechanisms underlying A?-stimulated ROS production. Here, we identified ion channels involved in A?-induced microglial ROS production and in A?-induced microglial priming. Acute stimulation of microglial cells with either fibrillar A?(1-42) (fA?(1-42) ) or soluble A?(1-42) (sA?(1-42) ) caused significant increases in microglial ROS production, which were abolished by inhibition of TRPV1 cation channels with 5-iodo-resiniferatoxin (I-RTX), but were unaffected by inhibition of K(+) channels with charybdotoxin (CTX). Furthermore, pretreatment with either fA?(1-42) or sA?(1-42) induced microglial priming, that is, increased ROS production upon secondary stimulation with the phorbol ester PMA. Microglial priming induced by fA?(1-42) or sA?(1-42) remained unaffected by TRPV1 channel inhibition with I-RTX. However, sA?(1-42) -induced priming was inhibited by CTX and margatoxin, but not by TRAM-34 or paxilline, indicating a role of Kv1.3 voltage-gated K(+) channels, but not of Ca(2+) -activated K(+) channels, in the priming process. In summary, our data suggest that in microglia A?-induced ROS production and priming are differentially regulated by ion channels, and that TRPV1 cation channels and Kv1.3?K(+) channels may provide potential therapeutic targets to reduce microglia-induced oxidative stress in Alzheimer's disease. PMID:21321937

Schilling, Tom; Eder, Claudia

2011-12-01

227

Arylhydrocarbon receptor (AhR) activation in airway epithelial cells induces MUC5AC via reactive oxygen species (ROS) production.  

PubMed

The dioxins and dioxin-like compounds in cigarette smoke regulate various immunological responses via the arylhydrocarbon receptor (AhR). These environmental toxicants are known to cause bronchitis, asthma, chronic obstructive pulmonary disease (COPD), and lung cancer. Recent studies have demonstrated that AhR activation upregulates the expression of mucin 5AC, oligomeric mucus/gel-forming (MUC5AC) in the airway epithelial cell line. However, the mechanism for the production of mucin has not been clarified. In this study, we investigated the role and pathway of AhR in airway epithelial cells by using selective agonists and antagonists. After stimulation with or without benzopyrene (B[a]P), an AhR agonist, MUC5AC expression was measured by real-time RT-PCR. The mechanism of AhR-induced MUC5AC expression in airway epithelial cells was studied in terms of the production of cytokine and reactive oxygen species (ROS). Treatment with B[a]P increased ROS generation in NCI-H??? cells. Furthermore, B[a]P-induced MUC5AC upregulation and mucin production were inhibited by AhR siRNA or the use of an antioxidative agent. These results suggest that the AhR-induced increase of mucin production is partially mediated by ROS generation. An antioxidant therapy approach may help to cure AhR-induced mucus hypersecretory diseases. PMID:20709182

Chiba, Takahito; Uchi, Hiroshi; Tsuji, Gaku; Gondo, Hisaki; Moroi, Yoichi; Furue, Masutaka

2011-02-01

228

Prolonged production of reactive oxygen species in response to BCR stimulation promotes B cell activation and proliferation  

PubMed Central

We have investigated the intracellular sources and physiological function of reactive oxygen species (ROS) produced in primary B cells in response to B cell antigen receptor (BCR) stimulation. BCR stimulation of primary resting murine B cells induced the rapid production of ROS that occurred within minutes, and was maintained for at least 24 h following receptor stimulation. While the early production of ROS (0-2 h) was dependent on the Nox2 isoform of NADPH oxidase, at later stages of B cell activation (6-24 h) ROS were generated by a second pathway, which appeared to be dependent on mitochondrial respiration. B cells from mice deficient in the Nox2 NADPH oxidase complex lacked detectible early production of extracellular and intracellular ROS following BCR stimulation, but had normal proximal BCR signaling and BCR-induced activation and proliferation in vitro, and mounted normal or somewhat elevated antibody responses in vivo. In contrast, neutralizing both pathways of BCR-derived ROS with the scavenger N-acetylcysteine resulted in impaired in vitro BCR-induced activation and proliferation, and attenuated BCR signaling through the phosphatidylinositol 3-kinase pathway at later times. These results indicate that the production of ROS downstream of the BCR is derived from at least two distinct cellular sources and plays a critical role at the later stages of B cell activation by promoting sustained BCR signaling via the PI3K pathway, which is needed for effective B cell responses to antigen.

Wheeler, Matthew L.; DeFranco, Anthony L.

2012-01-01

229

Dihydroorotate dehydrogenase is required for N-(4-hydroxyphenyl)retinamide-induced reactive oxygen species production and apoptosis.  

PubMed

The synthetic retinoid N-(4-hydroxyphenyl)retinamide (4HPR) exhibits anticancer activity in vivo and triggers apoptosis in transformed cells in vitro. Thus, apoptosis induction is acknowledged as a mechanistic underpinning for 4HPR's cancer preventive and therapeutic effects. Apoptosis induction by 4HPR is routinely preceded by and dependent on the production of reactive oxygen species (ROS) in transformed cells. Very little evidence exists, outside the possible involvement of the mitochondrial electron transport chain or the plasma membrane NADPH oxidase complex, that would pinpoint the predominant site of 4HPR-induced ROS production in transformed cells. Here, we investigated the role of dihydroorotate dehydrogenase (DHODH; an enzyme associated with the mitochondrial electron transport chain and required for de novo pyrimidine synthesis) in 4HPR-induced ROS production and attendant apoptosis in transformed skin and prostate epithelial cells. In premalignant prostate epithelial cells and malignant cutaneous keratinocytes the suppression of DHODH activity by the chemical inhibitor teriflunomide or the reduction in DHODH protein expression by RNA interference markedly reduced 4HPR-induced ROS generation and apoptosis. Conversely, colon carcinoma cells that lacked DHODH expression were markedly resistant to the pro-oxidant and cytotoxic effects of 4HPR. Together, these results strongly implicate DHODH in 4HPR-induced ROS production and apoptosis. PMID:20399851

Hail, Numsen; Chen, Ping; Kepa, Jadwiga J; Bushman, Lane R; Shearn, Colin

2010-07-01

230

Dihydroorotate dehydrogenase is required for N-(4-hydroxyphenyl)retinamide-induced reactive oxygen species production and apoptosis  

PubMed Central

The synthetic retinoid N-(4-hydroxyphenyl)retinamide (4HPR) exhibits anticancer activity in vivo and triggers apoptosis in transformed cells in vitro. Thus, apoptosis induction is acknowledged as a mechanistic underpinning for 4HPR's cancer preventive and therapeutic effects. Apoptosis induction by 4HPR is routinely preceded by and dependent on the production of reactive oxygen species (ROS) in transformed cells. Very little evidence exists outside the possible involvement of the mitochondrial electron transport chain or the plasma membrane NADPH oxidase complex, which would pinpoint the predominant site of 4HPR-induced ROS production in transformed cells. Here, we investigated the role of dihydroorotate dehydrogenase (DHODH, an enzyme associated with the mitochondrial electron transport chain and required for de novo pyrimidine synthesis) in 4HPR-induced ROS production and attendant apoptosis in transformed skin and prostate epithelial cells. In premalignant prostate epithelial cells and malignant cutaneous keratinocytes the suppression of DHODH activity by the chemical inhibitor teriflunomide or the reduction in DHODH protein expression by RNA interference markedly reduced 4HPR-induced ROS generation and apoptosis. Conversely, colon carcinoma cells that lacked DHODH expression were markedly resistant to the prooxidant and cytotoxic effects of 4HPR. Together, these results strongly implicate DHODH in 4HPR-induced ROS production and apoptosis.

Hail, Numsen; Chen, Ping; Kepa, Jadwiga J.; Bushman, Lane R.; Shearn, Colin

2010-01-01

231

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

232

A role for spermine oxidase as a mediator of reactive oxygen species production in HIV-Tat-induced neuronal toxicity.  

PubMed

Chronic oxidative stress, which occurs in brain tissues of HIV-infected patients, is involved in the pathogenesis of HIV-associated dementia. Oxidative stress can be induced by HIV-1-secreted proteins, either directly or indirectly through the release of cytotoxic factors. In particular, HIV-1 Tat is able to induce neuronal death by interacting with and activating the polyamine-sensitive subtype of the NMDA receptor (NMDAR). Here, we focused on the role of polyamine catabolism in Tat-induced oxidative stress in human neuroblastoma (SH-SY5Y) cells. First, Tat was found to induce reactive oxygen species production and to affect cell viability in SH-SY5Y cells, these effects being mediated by spermine oxidase (SMO). Second, Tat was observed to increase SMO activity as well as decreasing the intracellular spermine levels. Third, Tat-induced SMO activation was completely prevented by the NMDAR antagonist MK-801, clearly indicating an involvement of NMDAR stimulation. Finally, pretreatment of cells with N-acetylcysteine, a scavenger of H?O?, and with MK-801 was able to completely inhibit reactive oxygen species formation and to restore cell viability. Altogether, these data strongly suggest a role for polyamine catabolism-derived H?O? in neurotoxicity as elicited by Tat-stimulated NMDAR. PMID:23665428

Capone, Caterina; Cervelli, Manuela; Angelucci, Emanuela; Colasanti, Marco; Macone, Alberto; Mariottini, Paolo; Persichini, Tiziana

2013-10-01

233

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

234

Ischemic Preconditioning Preserves Mitochondrial Membrane Potential and Limits Reactive Oxygen Species Production  

PubMed Central

Background Mitochondrial superoxide radical (O2•?) production increases after cardiac ischemia-reperfusion (IR). Ischemic preconditioning (IPC) preserves mitochondrial function and attenuates O2•? production, but the mechanism is unknown. Mitochondrial membrane potential (m??) is known to affect O2•? production; mitochondrial depolarization decreases O2•? formation. We examined the relationship between O2•? production and m?? during IR and IPC. Materials/Methods Rat hearts were subjected to Control or IPC. Mitochondria were isolated at end-equilibration (End EQ), end-ischemia (End I) and end-reperfusion (End RP). m?? was measured using a tetraphenylphosphonium electrode. Mitochondrial O2•? production was measured by electron paramagnetic resonance (EPR) using DMPO spin trap. Cytochrome c levels were measured using high pressure liquid chromatography. Results IPC preserved m?? at End I (?156±5 vs. ?131±6 mV, p<0.001) and End RP (?168±2 vs. ?155±2 mV, p<0.05). At End RP, IPC attenuated O2•? production (2527±221 vs. 3523±250 AU/mg protein, p<0.05). IPC preserved cytochrome c levels (351±14 vs. 269±16 picomoles/mg protein, p<0.05) at End RP, and decreased mitochondrial cristae disruption (10±4 vs. 33±7%, p<0.05) and amorphous density formation (18±4 vs. 28±1%, p<0.05). Conclusion We conclude that IPC preserves m??, possibly by limiting disruption of mitochondrial inner membrane. IPC also decreases mitochondrial O2•? production and preserves mitochondrial ultrastructure after IR. While it was previously held that slight decreases in m?? decrease O2•? production, our results indicate that preservation of m?? is associated with decreased O2•? and preservation of cardiac function in IPC. These findings indicate that the mechanism of IPC may not involve m?? depolarization, but rather preservation of mitochondrial electrochemical potential.

Quarrie, Ricardo; Lee, Daniel S.; Steinbaugh, Gregory; Cramer, Brandon; Erdahl, Warren; Pfeiffer, Douglas R.; Zweier, Jay L.; Crestanello, Juan A.

2012-01-01

235

The cyclopentenone (A2/J2) isoprostanes--unique, highly reactive products of arachidonate peroxidation.  

PubMed

Cyclopentenone (A2/J2) isoprostanes (IsoPs) are a group of prostaglandin (PG)-like compounds generated in vivo from the free radical-induced peroxidation of arachidonic acid. Unlike other classes of IsoPs, cyclopentenone IsoPs contain highly reactive unsaturated carbonyl moieties on the prostane ring analogous to cyclooxygenase-derived PGA2 and PGJ2 that readily adduct relevant biomolecules such as thiols via Michael addition. The purpose of this review is to summarize our knowledge of the A2/J2-IsoPs. As a starting point, we will briefly discuss the formation and biological properties of PGA2 and PGJ2. Next, we will review studies definitively showing that cyclopentenone IsoPs are formed in large amounts in vivo. This is in marked contrast to cyclopentenone PGs, for which little evidence exists that they are endogenously produced. Subsequently, we will discuss studies related to the chemical syntheses of the 15-A2-IsoP series of cyclopentenone IsoPs. The successful synthesis of these compounds provides the recent impetus to explore the metabolism and biological properties of A-ring IsoPs, particularly as modulators of inflammation, and this work will be discussed. Finally, the formation of cyclopentenone IsoP-like compounds from other fatty acids such as linolenic acid and docosahexaenoic acid will be detailed. PMID:15650409

Milne, Ginger L; Musiek, Erik S; Morrow, Jason D

2005-01-01

236

Wogonin Induces Reactive Oxygen Species Production and Cell Apoptosis in Human Glioma Cancer Cells  

PubMed Central

Glioma is the most common primary adult brain tumor with poor prognosis because of the ease of spreading tumor cells to other regions of the brain. Cell apoptosis is frequently targeted for developing anti-cancer drugs. In the present study, we have assessed wogonin, a flavonoid compound isolated from Scutellaria baicalensis Georgi, induced ROS generation, endoplasmic reticulum (ER) stress and cell apoptosis. Wogonin induced cell death in two different human glioma cells, such as U251 and U87 cells but not in human primary astrocytes (IC 50 > 100 ?M). Wogonin-induced apoptotic cell death in glioma cells was measured by propidine iodine (PI) analysis, Tunnel assay and Annexin V staining methods. Furthermore, wogonin also induced caspase-9 and caspase-3 activation as well as up-regulation of cleaved PARP expression. Moreover, treatment of wogonin also increased a number of signature ER stress markers glucose-regulated protein (GRP)-78, GRP-94, Calpain I, and phosphorylation of eukaryotic initiation factor-2? (eIF2?). Treatment of human glioma cells with wogonin was found to induce reactive oxygen species (ROS) generation. Wogonin induced ER stress-related protein expression and cell apoptosis was reduced by the ROS inhibitors apocynin and NAC (N-acetylcysteine). The present study provides evidence to support the fact that wogonin induces human glioma cell apoptosis mediated ROS generation, ER stress activation and cell apoptosis.

Tsai, Cheng-Fang; Yeh, Wei-Lan; Huang, Ssu Ming; Tan, Tzu-Wei; Lu, Dah-Yuu

2012-01-01

237

Reactive extraction of Jatropha curcas L. seed for production of biodiesel: process optimization study.  

PubMed

Biodiesel from Jatropha curcas L. seed is conventionally produced via a two-step method: extraction of oil and subsequent esterification/transesterification to fatty acid methyl esters (FAME), commonly known as biodiesel. Contrarily, in this study, a single step in situ extraction, esterification and transesterification (collectively known as reactive extraction) of J. curcas L. seed to biodiesel, was investigated and optimized. Design of experiments (DOE) was used to study the effect of various process parameters on the yield of FAME. The process parameters studied include reaction temperature (30-60 degrees C), methanol to seed ratio (5-20 mL/g), catalyst loading (5-30 wt %), and reaction time (1-24 h). The optimum reaction condition was then obtained by using response surface methodology (RSM) coupled with central composite design (CCD). Results showed that an optimum biodiesel yield of 98.1% can be obtained under the following reaction conditions: reaction temperature of 60 degrees C, methanol to seed ratio of 10.5 mL/g, 21.8 wt % of H(2)SO(4), and reaction period of 10 h. PMID:20455588

Shuit, Siew Hoong; Lee, Keat Teong; Kamaruddin, Azlina Harun; Yusup, Suzana

2010-06-01

238

The Role of Metals in Production and Scavenging of Reactive Oxygen Species in Photosystem II.  

PubMed

Metal ions play a crucial role in enzymatic reactions in all photosynthetic organisms such as cyanobacteria, algae and plants. It well known that metal ions maintain the binding of substrate in the active site of the metalloenzymes and control the redox activity of the metalloenzyme in the enzymatic reaction. A large pigment-protein complex, PSII, known to serve as a water-plastoquinone oxidoreductase, contains three metal centers comprising non-heme iron, heme iron of Cyt b559 and the water-splitting manganese complex. Metal ions bound to PSII proteins maintain the electron transport from water to plastoquinone and regulate the pro-oxidant and antioxidant activity in PSII. In this review, attention is focused on the role of PSII metal centers in (i) the formation of superoxide anion and hydroxyl radicals by sequential one-electron reduction of molecular oxygen and the formation of hydrogen peroxide by incomplete two-electron oxidation of water; and (ii) the elimination of superoxide anion radical by one-electron oxidation and reduction (superoxide dismutase activity) and of hydrogen peroxide by two-electron oxidation and reduction (catalase activity). The balance between the formation and elimination of reactive oxygen species by PSII metal centers is discussed as an important aspect in the prevention of photo-oxidative damage of PSII proteins and lipids. PMID:24771559

Pospíšil, Pavel

2014-07-01

239

Hypoxia dysregulates the production of adiponectin and plasminogen activator inhibitor-1 independent of reactive oxygen species in adipocytes  

SciTech Connect

Low plasma levels of adiponectin (hypoadiponectinemia) and elevated circulating concentrations of plasminogen activator inhibitor (PAI)-1 are causally associated with obesity-related insulin resistance and cardiovascular disease. However, the mechanism that mediates the aberrant production of these two adipokines in obesity remains poorly understood. In this study, we investigated the effects of hypoxia and reactive oxygen species (ROS) on production of adiponectin and PAI-1 in 3T3-L1 adipocytes. Quantitative PCR and immunoassays showed that ambient hypoxia markedly suppressed adiponectin mRNA expression and its protein secretion, and increased PAI-1 production in mature adipocytes. Dimethyloxallyl glycine, a stabilizer of hypoxia-inducible factor 1{alpha} (HIF-1{alpha}), mimicked the hypoxia-mediated modulations of these two adipokines. Hypoxia caused a modest elevation of ROS in adipocytes. However, ablation of intracellular ROS by antioxidants failed to alleviate hypoxia-induced aberrant production of adiponectin and PAI-1. On the other hand, the antioxidants could reverse hydrogen peroxide (H{sub 2}O{sub 2})-induced dysregulation of adiponectin and PAI-1 production. H{sub 2}O{sub 2} treatment decreased the expression levels of peroxisome proliferator-activated receptor gamma (PPAR{gamma}) and CCAAT/enhancer binding protein (C/EBP{alpha}), but had no effect on HIF-1{alpha}, whereas hypoxia stabilized HIF-1{alpha} and decreased expression of C/EBP{alpha}, but not PPAR{gamma}. Taken together, these data suggest that hypoxia and ROS decrease adiponectin production and augment PAI-1 expression in adipocytes via distinct signaling pathways. These effects may contribute to hypoadiponectinemia and elevated PAI-1 levels in obesity, type 2 diabetes, and cardiovascular diseases.

Chen Baoying [Department of Medicine, University of Hong Kong, Hong Kong (China); Department of Radiology, Tangdu Hospital, Fourth Military Medical University (China); Lam, Karen S.L. [Department of Medicine, University of Hong Kong, Hong Kong (China); Wang Yu [Genome Research Center, University of Hong Kong, Hong Kong (China); Wu Donghai [Guangzhou Institute of Biomedicine and Health, Chinese Academy of Sciences (China); Lam, Michael C. [Department of Medicine, University of Hong Kong, Hong Kong (China); Shen Jiangang [School of Chinese Medicine, University of Hong Kong (China); Wong Laiching [Department of Medicine, University of Hong Kong, Hong Kong (China); Hoo, Ruby L.C. [Department of Medicine, University of Hong Kong, Hong Kong (China); Zhang Jialiang [Department of Medicine, University of Hong Kong, Hong Kong (China); Xu Aimin [Department of Medicine, University of Hong Kong, Hong Kong (China) and Genome Research Center, University of Hong Kong, Hong Kong (China)]. E-mail: amxu@hkucc.hku.hk

2006-03-10

240

CCL20 is overexpressed in Mycobacterium tuberculosis-infected monocytes and inhibits the production of reactive oxygen species (ROS)  

PubMed Central

CCL20 is a chemokine that attracts immature dendritic cells. We show that monocytes, cells characteristic of the innate immune response, infected with Mycobacterium tuberculosis express the CCL20 gene at a much higher level than the same cells infected with non-tuberculous mycobacteria. Interferon (IFN)-?, a fundamental cytokine in the immune response to tuberculosis, strongly inhibits both the transcription and the translation of CCL20. We have also confirmed that dendritic cells are a suitable host for mycobacteria proliferation, although CCL20 does not seem to influence their intracellular multiplication rate. The chemokine, however, down-regulates the characteristic production of reactive oxygen species (ROS) induced by M. tuberculosis in monocytes, which may affect the activity of the cells. Apoptosis mediated by the mycobacteria, possibly ROS-dependent, was also inhibited by CCL20.

Rivero-Lezcano, O M; Gonzalez-Cortes, C; Reyes-Ruvalcaba, D; Diez-Tascon, C

2010-01-01

241

Volatile products and endpoint detection in reactive ion etching of III-V compounds with a broad beam ECR source  

NASA Astrophysics Data System (ADS)

A broad beam ECR plasma source has been applied to low pressure hydrocarbon reactive ion etching of III-V compounds. An additional RF bias is applied to the sample stage providing the means for independent control of current density and bombarding energy of ions on the sample surface. Chemical aspects of the etching process have been investigated with a differentially pumped energy selective Hiden quadrupole mass spectrometer. In particular, the dominant group III volatile species in InP and GaAs have been clearly identified for the first time as In(CH 3) 2+ and Ga(CH 3) 2+, respectively. Finally, we report the application of volatile product identification to endpoint detection and demonstrate resolution for multiple layers as thin as 50 Å. These results confirm that etch uniformity over the surface area of the sample is very good for these sources.

Melville, D. L.; Budinavicius, J.; Thompson, D. A.; Simmons, J. G.

242

?-Cell Uncoupling Protein 2 Regulates Reactive Oxygen Species Production, Which Influences Both Insulin and Glucagon Secretion  

PubMed Central

OBJECTIVE The role of uncoupling protein 2 (UCP2) in pancreatic ?-cells is highly debated, partly because of the broad tissue distribution of UCP2 and thus limitations of whole-body UCP2 knockout mouse models. To investigate the function of UCP2 in the ?-cell, ?-cell–specific UCP2 knockout mice (UCP2BKO) were generated and characterized. RESEARCH DESIGN AND METHODS UCP2BKO mice were generated by crossing loxUCP2 mice with mice expressing rat insulin promoter-driven Cre recombinase. Several in vitro and in vivo parameters were measured, including respiration rate, mitochondrial membrane potential, islet ATP content, reactive oxygen species (ROS) levels, glucose-stimulated insulin secretion (GSIS), glucagon secretion, glucose and insulin tolerance, and plasma hormone levels. RESULTS UCP2BKO ?-cells displayed mildly increased glucose-induced mitochondrial membrane hyperpolarization but unchanged rates of uncoupled respiration and islet ATP content. UCP2BKO islets had elevated intracellular ROS levels that associated with enhanced GSIS. Surprisingly, UCP2BKO mice were glucose-intolerant, showing greater ?-cell area, higher islet glucagon content, and aberrant ROS-dependent glucagon secretion under high glucose conditions. CONCLUSIONS Using a novel ?-cell–specific UCP2KO mouse model, we have shed light on UCP2 function in primary ?-cells. UCP2 does not behave as a classical metabolic uncoupler in the ?-cell, but has a more prominent role in the regulation of intracellular ROS levels that contribute to GSIS amplification. In addition, ?-cell UCP2 contributes to the regulation of intraislet ROS signals that mediate changes in ?-cell morphology and glucagon secretion.

Robson-Doucette, Christine A.; Sultan, Sobia; Allister, Emma M.; Wikstrom, Jakob D.; Koshkin, Vasilij; Bhatacharjee, Alpana; Prentice, Kacey J.; Sereda, Samuel B.; Shirihai, Orian S.; Wheeler, Michael B.

2011-01-01

243

Patterns of cytokine production by mycobacterium-reactive human T-cell clones.  

PubMed Central

To gain insight into the functional capacity of human T cells in the immune response against Mycobacterium tuberculosis, we evaluated the spectrum of cytokines produced by mycobacterium-reactive human T-cell clones. Nine of 11 T-cell clones bearing alpha beta or gamma delta T-cell receptors produced both Th1 and Th2 cytokines, a pattern resembling that of murine Th0 clones. The most frequent pattern was secretion of gamma interferon, tumor necrosis factor alpha (TNF), and interleukin-10 (IL-10), in combination with IL-2, IL-5, or both. Two clones produced only Th1 cytokines, and none produced exclusively Th2 cytokines. Although IL-4 was not detected in cell culture supernatants, IL-4 mRNA was detected by polymerase chain reaction amplification in two of six clones. There were no differences between the cytokine profiles of alpha beta and gamma delta T cells. A striking finding was the markedly elevated concentrations of TNF in clone supernatants, independent of the other cytokines produced. Supernatants from mycobacterium-stimulated T-cell clones, in combination with granulocyte-macrophage colony-stimulating factor, induced aggregation of bone-marrow-derived macrophages, and this effect was abrogated by antibodies to TNF. The addition of recombinant TNF to granulocyte-macrophage colony-stimulating factor markedly enhanced macrophage aggregation, indicating that TNF produced by T cells may be an important costimulus for the granulomatous host response to mycobacteria. The cytokines produced by T cells may exert immunoregulatory and immunopathologic effects and thus mediate some of the clinical manifestations of tuberculosis.

Barnes, P F; Abrams, J S; Lu, S; Sieling, P A; Rea, T H; Modlin, R L

1993-01-01

244

Entropy and chemical change. 1: Characterization of product (and reactant) energy distributions in reactive molecular collisions: Information and enthropy deficiency  

NASA Technical Reports Server (NTRS)

Optimal means of characterizing the distribution of product energy states resulting from reactive collisions of molecules with restricted distributions of initial states are considered, along with those for characterizing the particular reactant state distribution which yields a given set of product states at a specified total energy. It is suggested to represent the energy-dependence of global-type results in the form of square-faced bar plots, and of data for specific-type experiments as triangular-faced prismatic plots. The essential parameters defining the internal state distribution are isolated, and the information content of such a distribution is put on a quantitative basis. The relationship between the information content, the surprisal, and the entropy of the continuous distribution is established. The concept of an entropy deficiency, which characterizes the specificity of product state formation, is suggested as a useful measure of the deviance from statistical behavior. The degradation of information by experimental averaging is considered, leading to bounds on the entropy deficiency.

Bernstein, R. B.; Levine, R. D.

1972-01-01

245

Asian Dust Particles Induce Macrophage Inflammatory Responses via Mitogen-Activated Protein Kinase Activation and Reactive Oxygen Species Production  

PubMed Central

Asian dust is a springtime meteorological phenomenon that originates in the deserts of China and Mongolia. The dust is carried by prevailing winds across East Asia where it causes serious health problems. Most of the information available on the impact of Asian dust on human health is based on epidemiological investigations, so from a biological standpoint little is known of its effects. To clarify the effects of Asian dust on human health, it is essential to assess inflammatory responses to the dust and to evaluate the involvement of these responses in the pathogenesis or aggravation of disease. Here, we investigated the induction of inflammatory responses by Asian dust particles in macrophages. Treatment with Asian dust particles induced greater production of inflammatory cytokines interleukin-6 and tumor necrosis factor-? (TNF-?) compared with treatment with soil dust. Furthermore, a soil dust sample containing only particles ?10??m in diameter provoked a greater inflammatory response than soil dust samples containing particles >10??m. In addition, Asian dust particles-induced TNF-? production was dependent on endocytosis, the production of reactive oxygen species, and the activation of nuclear factor-?B and mitogen-activated protein kinases. Together, these results suggest that Asian dust particles induce inflammatory disease through the activation of macrophages.

Higashisaka, Kazuma; Fujimura, Maho; Taira, Mayu; Yoshida, Tokuyuki; Tsunoda, Shin-ichi; Baba, Takashi; Yamaguchi, Nobuyasu; Nabeshi, Hiromi; Yoshikawa, Tomoaki; Nasu, Masao; Tsutsumi, Yasuo

2014-01-01

246

Loss of TRPML1 promotes production of reactive oxygen species: is oxidative damage a factor in mucolipidosis type IV?  

PubMed

TRPML1 (transient receptor potential mucolipin 1) is a lysosomal ion channel permeable to cations, including Fe2+. Mutations in MCOLN1, the gene coding for TRPML1, cause the LSD (lysosomal storage disease) MLIV (mucolipidosis type IV). The role of TRPML1 in the cell is disputed and the mechanisms of cell deterioration in MLIV are unclear. The demonstration of Fe2+ buildup in MLIV cells raised the possibility that TRPML1 dissipates lysosomal Fe2+ and prevents its accumulation. Since Fe2+ catalyses the production of ROS (reactive oxygen species), we set out to test whether or not the loss of TRPML1 promotes ROS production by Fe2+ trapped in lysosomes. Our data show that RPE1 (retinal pigmented epithelial 1) cells develop a punctate mitochondrial phenotype within 48 h of siRNA-induced TRPML1-KD (knockdown). This mitochondrial fragmentation was aggravated by Fe2+ exposure, but was reversed by incubation with the ROS chelator ?-Toc (?-tocopherol). The exposure of TRPML1-KD cells to Fe2+ led to loss of ??m (mitochondrial membrane potential), ROS buildup, lipid peroxidation and increased transcription of genes responsive to cytotoxic oxidative stress in TRPML1-KD cells. These data suggest that TRPML1 redistributes Fe2+ between the lysosomes and the cytoplasm. Fe2+ buildup caused by TRPML1 loss potentiates ROS production and leads to mitochondrial deterioration. Beyond suggesting a new model for MLIV pathogenesis, these data show that TRPML1's role in the cell extends outside lysosomes. PMID:24192042

Coblentz, Jessica; St Croix, Claudette; Kiselyov, Kirill

2014-01-15

247

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

Microsoft Academic Search

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

Yoshikazu Tashiro; Ryuji Kodama; Hiroshi Sugai; Katsuhiko Suzuki; Shingo Matsuoka

2000-01-01

248

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

249

Increased mitochondrial reactive oxygen species production in newborn brain during hypoglycemia  

Microsoft Academic Search

Hypoglycemia is associated with gray and white matter injury in immature brain, but the specific mechanisms responsible for hypoglycemic brain injury remain poorly defined. We postulated that mitochondrial electron transport chain function is altered during hypoglycemia due to the decreased availability of reducing equivalents, and that altered activity of the electron transport chain would increase mitochondrial production of free radicals

Jane E. McGowan; Lei Chen; Daqing Gao; Michael Trush; Chiming Wei

2006-01-01

250

Measurement of Nuclear Transparencies from Exclusive rho0 Meson Production in Muon-Nucleus Scattering at 470 GeV  

Microsoft Academic Search

Nuclear transparencies measured in exclusive incoherent rho0 meson production from hydrogen, deuterium, carbon, calcium, and lead in muon-nucleus scattering are reported. The data were obtained with the E665 spectrometer using the Fermilab Tevatron muon beam with a mean beam energy of 470 GeV. Increases in the nuclear transparencies are observed as the virtuality of the photon increases, in qualitative agreement

M. R. Adams; S. Aïd; P. L. Anthony; D. A. Averill; M. D. Baker; B. R. Baller; A. Banerjee; A. A. Bhatti; U. Bratzler; H. M. Braun; H. Breidung; W. Busza; T. J. Carroll; H. L. Clark; J. M. Conrad; R. Davisson; I. Derado; S. K. Dhawan; F. S. Dietrich; W. Dougherty; T. Dreyer; V. Eckardt; U. Ecker; M. Erdmann; F. Faller; G. Y. Fang; J. Figiel; R. W. Finlay; H. J. Gebauer; D. F. Geesaman; K. A. Griffioen; R. S. Guo; J. Haas; C. Halliwell; D. Hantke; K. H. Hicks; V. W. Hughes; H. E. Jackson; G. Jancso; D. M. Jansen; Z. Jin; S. Kaufman; R. D. Kennedy; E. R. Kinney; T. Kirk; H. G. Kobrak; A. V. Kotwal; S. Kunori; S. Lancaster; J. J. Lord; H. J. Lubatti; D. McLeod; P. Madden; S. Magill; A. Manz; H. Melanson; D. G. Michael; H. E. Montgomery; J. G. Morfin; R. B. Nickerson; S. O'Day; K. Olkiewicz; L. Osborne; R. Otten; V. Papavassiliou; B. Pawlik; F. M. Pipkin; D. H. Potterveld; E. J. Ramberg; A. Röser; J. J. Ryan; C. W. Salgado; A. Salvarani; H. Schellman; M. Schmitt; N. Schmitz; K. P. Schüler; G. Siegert; A. Skuja; G. A. Snow; S. Söldner-Rembold; P. Spentzouris; H. E. Stier; P. Stopa; R. A. Swanson; H. Venkataramania; M. Wilhelm; Richard Wilson; W. Wittek; S. A. Wolbers; A. Zghiche; T. Zhao

1995-01-01

251

P11 Resonances with Dubna-Mainz-Taipei dynamical model for ?N scattering and pion electromagnetic production  

NASA Astrophysics Data System (ADS)

We present the results on P11 resonances obtained with Dubna-Mainz-Taipei (DMT) dynamical model for pion-nucleon scattering and pion electromagnetic production. The extracted values agree well, in general, with PDG values. One pole is found corresponding to the Roper resonance and two more resonances are definitely needed in DMT model. We further find indication for a narrow P11 resonance at around 1700 MeV with a width ~ 50 MeV in both ?N and ?? reactions.

Yang, Shin Nan; Kamalov, S. S.; Tiator, L.

2012-04-01

252

Measurement of inclusive jet production in deep-inelastic scattering at high Q 2 and determination of the strong coupling  

Microsoft Academic Search

Inclusive jet production is studied in neutral current deep-inelastic positron–proton scattering at large four momentum transfer squared Q2>150GeV2 with the H1 detector at HERA. Single and double differential inclusive jet cross sections are measured as a function of Q2 and of the transverse energy ET of the jets in the Breit frame. The measurements are found to be well described

A. Aktas; C. Alexa; V. Andreev; T. Anthonis; B. Antunovic; S. Aplin; A. Asmone; A. Astvatsatourov; S. Backovic; A. Baghdasaryan; 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; M. Deak; Y. de Boer; B. Delcourt; M. Del Degan; J. Delvax; 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. Falkiewicz; P. J. W. Faulkner; L. Favart; A. Fedotov; R. Felst; J. Feltesse; L. Finke; M. Fleischer; A. Fomenko; G. Franke; T. Frisson; E. Gabathuler; J. Gayler; S. Ghazaryan; S. Ginzburgskaya; A. Glazov; I. Glushkov; L. Goerlich; M. Goettlich; N. Gogitidze; S. Gorbounov; M. Gouzevitch; C. Grab; T. Greenshaw; 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; M. Jacquet; M. E. Janssen; 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; A. Knutsson; V. Korbel; P. Kostka; M. Kraemer; K. Krastev; J. Kretzschmar; A. Kropivnitskaya; K. Krüger; M. P. J. Landon; W. Lange; G. Laštovi?ka-Medin; P. Laycock; A. Lebedev; G. Leibenguth; V. Lendermann; S. Levonian; G. Li; L. Lindfeld; K. Lipka; A. Liptaj; B. List; J. List; N. Loktionova; R. Lopez-Fernandez; V. Lubimov; A.-I. Lucaci-Timoce; L. Lytkin; A. Makankine; E. Malinovski; P. Marage; Ll. 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; A. Mohamed; F. Moreau; A. Morozov; J. V. Morris; M. U. Mozer; K. Müller; P. Murín; K. Nankov; B. Naroska; Th. 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; Th. Papadopoulou; C. Pascaud; G. D. Patel; H. Peng; E. Perez; D. Perez-Astudillo; A. Perieanu; A. Petrukhin; I. Picuric; S. Piec; D. Pitzl; R. Pla?akyt?; B. Povh; T. Preda; P. Prideaux; V. Radescu; A. J. Rahmat; N. Raicevic; T. Ravdandorj; P. Reimer; 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; 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; Z. Staykova; M. Steder; B. Stella; J. Stiewe; U. Straumann; D. Sunar; T. Sykora; V. Tchoulakov; G. Thompson; P. D. Thompson; T. Toll; F. Tomasz; T. H. Tran; D. Traynor; T. N. Trinh; P. Truöl; I. Tsakov; B. Tseepeldorj; G. Tsipolitis; I. Tsurin; J. Turnau; E. Tzamariudaki; K. Urban; D. Utkin; A. Valkárová; C. Vallée; P. Van Mechelen; A. Vargas Trevino; Y. Vazdik; S. Vinokurova; V. Volchinski; G. Weber; R. Weber; D. Wegener; C. Werner; M. Wessels; Ch. Wissing; R. Wolf; E. Wünsch; S. Xella; W. Yan; V. Yeganov; J. Žá?ek; J. Zálešák; Z. Zhang; A. Zhelezov; Y. C. Zhu; T. Zimmermann; H. Zohrabyan; F. Zomer

2007-01-01

253

Low production of reactive oxygen species in granulocytes is associated with organ damage in systemic lupus erythematosus  

PubMed Central

Introduction Polymorphonuclear leukocytes (PMN) are main effector cells in the acute immune response. While the specific role of PMN in systemic lupus erythematosus (SLE) and autoimmunity is still unclear, their importance in chronic inflammation is gaining more attention. Here we investigate aspects of function, bone marrow release and activation of PMN in patients with SLE. Methods The following PMN functions and subsets were evaluated using flow cytometry; (a) production of reactive oxygen species (ROS) after ex vivo stimulation with phorbol 12-myristate 13-acetate (PMA) or Escherichia coli (E. coli); (b) capacity to phagocytose antibody-coated necrotic cell material; (c) PMN recently released from bone marrow, defined as percentage of CD10?D16low in peripheral blood, and (d) PMN activation markers; CD11b, CD62L and C5aR. Results SLE patients (n?=?92) showed lower ROS production compared with healthy controls (n?=?38) after activation ex vivo. The ROS production was not associated with corticosteroid dose or other immunotherapies. PMA induced ROS production was significantly reduced in patients with severe disease. In contrast, neither ROS levels after E. coli activation, nor the capacity to phagocytose were associated with disease severity. This suggests that decreased ROS production after PMA activation is a sign of changed PMN behaviour rather than generally impaired functions. The CD10?CD16low phenotype constitute 2% of PMN in peripheral blood of SLE patients compared with 6.4% in controls, indicating a decreased release of PMN from the bone marrow in SLE. A decreased expression of C5aR on PMN was observed in SLE patients, pointing towards in vivo activation. Conclusions Our results indicate that PMN from SLE patients have altered function, are partly activated and are released abnormally from bone marrow. The association between low ROS formation in PMN and disease severity is consistent with findings in other autoimmune diseases and might be considered as a risk factor.

2014-01-01

254

Elastic Scattering and Single Meson Production in Proton-Proton Collisions at 2.85 Bev  

Microsoft Academic Search

The Brookhaven National Laboratory twenty-inch liquid hydrogen bubble chamber was exposed to a monoenergetic beam of 2.85-Bev protons, elastically scattered from a carbon target in the internal beam of the Cosmotron. All two-prong events, excluding strange particle events, have been studied by the Yale High-Energy Group. The remaining interactions have been studied by the Brookhaven Bubble Chamber Group. Elastic scattering

G. A. Smith; H. Courant; E. C. Fowler; H. Kraybill; J. Sandweiss; H. Taft

1961-01-01

255

Completeness of the products of solutions to PDE and uniqueness theorems in inverse scattering  

Microsoft Academic Search

Let N= (U: (V2 + k2)u=O), N, = {@: (V2 + k2 -q(x))@=O) in 9 c R3, where 9 is a bounded domain, k=constant>O, q(x)ELm(9). Suppose that f€LP@),p) 1, and Jfu@dx=O for all UE N and @E NI. Then f=O. Results of this type are used to prove uniqueness theorems in inverse scattering. In particular, we prove that the scattering

A G Ramm

256

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

257

Production of reactive oxygen species by hemocytes from the marine mussel, Mytilus edulis: lysosomal localization and effect of xenobiotics.  

PubMed

Hemolymph of M. Edulis is rich in phagocytic hemocytes. Hemocytes contain numerous lysosomes which, in turn, contain various hydrolytic enzymes. Phagocytic activity of M. edulis hemocytes is thought to be associated with NAD(P)H-oxidase activity of the plasma membrane. The laser dye, dihydrorhodamine 123 (DHR), was used for cytochemical and biochemical detection of the generation of reactive oxygen species (ROS) by isolated M. edulis hemocytes. Hemocytes readily take up DHR from the suspension medium and selectively concentrate it in the lysosomes, wherein DHR is oxidized to fluorescent rhodamine 123. Concomitant uptake of DHR with superoxide dismutase or the spin-trap, tert-phenylbutyl nitrone, but not catalase markedly reduced fluorescence in the lysosomes implicating superoxide anion (O2-) but not hydrogen peroxide (H2O2) in DHR oxidation. Uptake of the anthraquinone, purpurin, and FeEDTA with DHR greatly amplified fluorescence within the lysosomes. These data are consistent with uptake of xenobiotics by hemocytes and their concentration in lysosomes wherein, ROS are generated in response to their accumulation. The rate of DHR oxidation by hemocytes was not stimulated by zymosan, a known stimulator of the oxidative burst. In vitro studies using the xanthine oxidase/hypoxanthine reaction to generate O2- and selective inhibitors of ROS production indicated that DHR is oxidized by O2- and H2O2 but not by .OH and that iron can participate in the reaction. Incubating isolated hemocytes promoted low-level, SOD-sensitive, FeEDTA-stimulated production of ethylene from alpha-keto-gamma-methiolbutyric acid, indicating the in situ formation of .OH via production of O2-. The above suggest that enhanced production of ROS in M. edulis hemocytes by xenobiotic accumulation within the lysosomal compartment should be considered in the toxic sequelae of exposure of marine molluscs to chemical pollutants. PMID:8646615

Winston, G W; Moore, M N; Kirchin, M A; Soverchia, C

1996-02-01

258

The neuromediator glutamate, through specific substrate interactions, enhances mitochondrial ATP production and reactive oxygen species generation in nonsynaptic brain mitochondria.  

PubMed

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. PMID:19304986

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

2009-05-22

259

Oxygen therapy does not increase production and damage induced by reactive oxygen species in focal cerebral ischemia.  

PubMed

Oxygen therapy with hyperbaric oxygen (HBO) or normobaric hyperoxia (NBO) improves outcome in experimental cerebral ischemia. However, an increased formation of reactive oxygen species (ROS) may be an undesirable side effect of oxygen therapy. We investigated the effect of both oxygen therapies on ROS production and adverse effects in murine focal ischemia. 25min after 90min filament-induced middle cerebral artery occlusion (MCAO), mice breathed either air, 100% O2 (NBO), or 100% O2 at 3 ata (HBO) for 60min. ROS were depicted on tissue sections after preischemic injection of hydroethidine, a marker of in vivo superoxide production. Moreover, infarct sizes were quantified in experiments using peroxybutinitrite (PBN) in mice treated with HBO. Effects of oxygen therapy were also tested in superoxide 2 knock-out mice. Both NBO and HBO significantly reduced superoxide radicals compared to air. Application of PBN had no additional protective effect when combined with HBO. Infarct volumes did not differ among SOD2 knock-out mice receiving air (34.0±19.6mm(3)), NBO (35.4±14.3mm(3)) or HBO (33.4±12.2mm(3)). In conclusion, brief episodes of oxygen therapy do not appear to promote damage inflicted by ROS in experimental stroke. PMID:24909618

Sun, Li; Wolferts, Guido; Veltkamp, Roland

2014-08-01

260

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

261

Production of laccase from Pleurotus florida using agro-wastes and efficient decolorization of Reactive blue 198.  

PubMed

Pleurotus florida NCIM 1243 produced laccase as the dominant lignolytic enzyme during the dye decolorization. Banana peel was the best substrate for extracellular laccase production under solid state fermentation when compared to mandarin peel and cantaloupe peel. The maximum activity of laccase (5.4 U/g) was detected on the 10 day. The ratio of banana peel: mandarin peel: cantaloupe peel (5:2:3) showed increased production of laccase (6.8 U/g). P. florida produced two extracellular laccase isoenzymes (L1 and L2). The half life of laccase at 60 degrees C was 2 h and at 4 h it retained 25% residual activity. P. florida laccase showed high thermostability and an interesting difference was noticed in the behavior of laccase isoenzymes at different temperature. The L1 isoenzyme of laccase showed remarked thermostability at 60 degrees C in the native PAGE when compared to L2 isoenzyme. The optimum pH, temperature and enzyme concentration for maximum decolorization was found to be 4.5, 60 degrees C and 1.2 U/ml, respectively. Partially purified laccase enzyme showed excellent decolorization activity to Reactive blue 198. The maximum decolorization (96%) was observed at lower dye concentrations (50-100 ppm) which decreased markedly when the dye concentration was increased beyond 150 ppm. The thermostable laccase of P. florida could be effectively used to decolorize the synthetic dyes in the textile effluent and other biotechnological applications. PMID:20586068

Sathishkumar, P; Murugesan, K; Palvannan, T

2010-08-01

262

The effects of new Alibernet red wine extract on nitric oxide and reactive oxygen species production in spontaneously hypertensive rats.  

PubMed

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. PMID:22720118

Kondrashov, Alexey; Vranková, Stanislava; Dovinová, Ima; Sev?ík, Rudolf; Parohová, Jana; Barta, Andrej; Pechá?ová, Olga; Kovacsová, Maria

2012-01-01

263

Induction of apoptosis in human multiple myeloma cell lines by ebselen via enhancing the endogenous reactive oxygen species production.  

PubMed

Ebselen a selenoorganic compound showing glutathione peroxidase like activity is an anti-inflammatory and antioxidative agent. Its cytoprotective activity has been investigated in recent years. However, experimental evidence also shows that ebselen causes cell death in several cancer cell types whose mechanism has not yet been elucidated. In this study, we examined the effect of ebselen on multiple myeloma (MM) cell lines in vitro. The results showed that ebselen significantly enhanced the production of reactive oxygen species (ROS) accompanied by cell viability decrease and apoptosis rate increase. Further studies revealed that ebselen can induce Bax redistribution from the cytosol to mitochondria leading to mitochondrial membrane potential ??m changes and cytochrome C release from the mitochondria to cytosol. Furtherly, we found that exogenous addition of N-acetyl cysteine (NAC) completely diminished the cell damage induced by ebselen. This result suggests that relatively high concentration of ebselen can induce MM cells apoptosis in culture by enhancing the production of endogenous ROS and triggering mitochondria mediated apoptotic pathway. PMID:24587987

Zhang, Liang; Zhou, Liwei; Du, Jia; Li, Mengxia; Qian, Chengyuan; Cheng, Yi; Peng, Yang; Xie, Jiayin; Wang, Dong

2014-01-01

264

Induction of Apoptosis in Human Multiple Myeloma Cell Lines by Ebselen via Enhancing the Endogenous Reactive Oxygen Species Production  

PubMed Central

Ebselen a selenoorganic compound showing glutathione peroxidase like activity is an anti-inflammatory and antioxidative agent. Its cytoprotective activity has been investigated in recent years. However, experimental evidence also shows that ebselen causes cell death in several cancer cell types whose mechanism has not yet been elucidated. In this study, we examined the effect of ebselen on multiple myeloma (MM) cell lines in vitro. The results showed that ebselen significantly enhanced the production of reactive oxygen species (ROS) accompanied by cell viability decrease and apoptosis rate increase. Further studies revealed that ebselen can induce Bax redistribution from the cytosol to mitochondria leading to mitochondrial membrane potential ??m changes and cytochrome C release from the mitochondria to cytosol. Furtherly, we found that exogenous addition of N-acetyl cysteine (NAC) completely diminished the cell damage induced by ebselen. This result suggests that relatively high concentration of ebselen can induce MM cells apoptosis in culture by enhancing the production of endogenous ROS and triggering mitochondria mediated apoptotic pathway.

Du, Jia; Li, Mengxia; Qian, Chengyuan; Cheng, Yi; Peng, Yang; Xie, Jiayin; Wang, Dong

2014-01-01

265

Isochoric Burn, an Internally Consistent Method for the Reactant to Product Transformation in Reactive Flow  

SciTech Connect

Mixture rules for partially reacted explosives differ amongst various models. For instance, JWL++ uses a partial pressure addition to compute an average zonal pressure, Ignition and Growth requires pressure equilibration and thermal equilibration of temperature dependent JWL EOSs, CHEETAH In Line RF also assumes temperature and pressure equilibration. It has been suggested in the past that a more realistic equilibration scheme should comprise isentropic pressure equilibration of the separate reacted and unreacted phases. This turns out not to be a proper path for equilibration. Rather, we find that the only internally consistent method is the evaluation of the equilibrium pressure that satisfies the particular conditions of reactant and product resulting from deflagration in a fixed volume.

Reaugh, J E; Lee, E L

2002-07-01

266

Spacecraft self-contamination due to back-scattering of outgas products  

NASA Technical Reports Server (NTRS)

The back-scattering of outgas contamination near an orbiting spacecraft due to intermolecular collisions was analyzed. Analytical tools were developed for making reasonably accurate quantitative estimates of the outgas contamination return flux, given a knowledge of the pertinent spacecraft and orbit conditions. Two basic collision mechanisms were considered: (1) collisions involving only outgas molecules (self-scattering) and (2) collisions between outgas molecules and molecules in the ambient atmosphere (ambient-scattering). For simplicity, the geometry was idealized to a uniformly outgassing sphere and to a disk oriented normal to the freestream. The method of solution involved an integration of an approximation of the Boltzmann kinetic equation known as the BGK (or Krook) model equation. Results were obtained in the form of simple equations relating outgas return flux to spacecraft and orbit parameters. Results were compared with previous analyses based on more simplistic models of the collision processes.

Robertson, S. J.

1976-01-01

267

Measurements of Product-Specific VOC Reactivities during the PROPHET 2008 field intensive using proton transfer reaction linear ion trap (PTR-LIT) mass spectrometry  

NASA Astrophysics Data System (ADS)

A major aim of the PROPHET 2008 field intensive conducted at the University of Michigan Biological Station was to more completely understand the local formation of secondary organic aerosol from oxidation of biogenic volatile organic compounds (BVOCs). This oxidation was monitored at every step including gas phase reactant VOCs, oxidants, reaction products, and aerosol number and size distribution. A proton transfer reaction - linear ion trap (PTR-LIT) mass spectrometer was developed and utilized to quantify and distinguish isomeric VOCs as well as test for interferents by allowing for MSn experiments while retaining a LOD in the 100 ppt range for most compounds. This field deployment marks the first time MVK and MACR have been speciated at ambient concentrations with an ion trap mass spectrometer. The extended capabilities of the PTR-LIT were used to measure a variety of VOCs and BVOC species and their oxidation products. We then use these and supporting data to calculate what we refer to as product specific reactivities. For example, the organic nitrate reactivity is defined as the first order rate of production of organic nitrate from VOC oxidation by OH. Similarly, we calculate the aerosol reactivities from published aerosol yields, as well as the NO3 reactivities, to compare the importance of different VOCs to ozone, nitrogen, and aerosol chemistry.

Mielke, L. H.; Slade, J. H.; Alaghmand, M.; Bertman, S. B.; Carroll, M.; Griffith, S. M.; Hansen, R. F.; Dusanter, S.; Stevens, P. S.; Hansel, A.; Shepson, P. B.

2009-12-01

268

The Use of HRP in Decolorization of Reactive Dyes and Toxicological Evaluation of Their Products  

PubMed Central

This work studied the potential use of horseradish peroxidase (HRP) in the decolorization of the following textile dyes: Drimarene Blue X-3LR (DMBLR), Drimarene Blue X-BLN (DMBBLN), Drimarene Rubinol X-3LR (DMR), and Drimarene Blue CL-R (RBBR). Dyes were individually tested in the reaction media containing 120?mg·L?1, considering the following parameters: temperature (20–45°C), H2O2 concentration (0–4.44?mmol·L?1), and reaction time (5 minutes, 1 and 24?h). The following conditions: 35°C, 0.55?mmol·L?1, and 1h, provided the best set of results of color removal for DMBLR (99%), DMBBLN (77%), DMR (94%), and RBBR (97%). It should be mentioned that only 5 minutes of reaction was enough to obtain 96% of decolorization for DMBLR and RBBR. After the decolorization reactions of DMBLR, DMR, and RBBR, it was possible to observe the reduction of Artemia salina mortality and the no significant increase in toxicity for the products generated from DMBBLN.

da Silva, Michelle Reis; de Sa, Livian Ribeiro Vasconcelos; Russo, Carlos; Scio, Elita; Ferreira-Leitao, Viridiana Santana

2010-01-01

269

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

270

Antioxidant-photosensitizer dual-loaded polymeric micelles with controllable production of reactive oxygen species.  

PubMed

Poly(ethylene glycol)-b-poly(caprolactone) (PEG-b-PCL) micelles dually loaded with both pheophorbide a (PhA) as a photosensitizer and ?-carotene (CAR) as a singlet oxygen ((1)O2) scavenger were designed to control photodynamic therapy (PDT) activity in cancer treatment. The CAR in the PhA/CAR micelles significantly diminished PhA-generated (1)O2 through direct (1)O2 scavenging, whereas the CAR molecules lost their (1)O2 scavenging activity when the PhA and CAR were spatially isolated by the disintegration of the PEG-b-PCL micelles. In cell-culture systems, light irradiation at a post-treatment time that corresponded to the presence of the micelles in the blood environment induced negligible phototoxicity, whereas light irradiation at a post-treatment time that corresponded to the presence of the micelles in the intracellular environment induced remarkable phototoxicity. In addition, a longer post-treatment time induced greater internalization of PhA/CAR micelles, which resulted in higher phototoxicity, suggesting an increase in photo killing activity against the tumor cells of interest. Thus, the co-loading of a (1)O2 generator and a (1)O2 scavenger into a single micelle is a potential strategy that may be useful in facilitating more accurate and reliable PDT with site-specific controllable production of singlet oxygen species for cancer treatment. PMID:24939615

Li, Li; Cho, Hana; Yoon, Kwon Hyeok; Kang, Han Chang; Huh, Kang Moo

2014-08-25

271

Sinoporphyrin sodium, a novel sensitizer, triggers mitochondrial-dependent apoptosis in ECA-109 cells via production of reactive oxygen species  

PubMed Central

Background Sonodynamic therapy (SDT) is a promising method that uses ultrasound to activate certain chemical sensitizers for the treatment of cancer. The purpose of this study was to investigate the sonoactivity of a novel sensitizer, sinoporphyrin sodium (DVDMS), and its sonotoxicity in an esophageal cancer (ECA-109) cell line. Methods The fluorescence intensity of DVDMS, hematoporphyrin, protoporphyrin IX, and Photofrin II was detected by fluorescence microscopy and flow cytometry. Generation of singlet oxygen was measured using a 1, 3-diphenylisobenzofuran experiment. A 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide assay was used to examine cell viability. Production of reactive oxygen species (ROS) and destabilization of the mitochondrial membrane potential were assessed by flow cytometry. Apoptosis was analyzed using Annexin-PE/7-amino-actinomycin D staining. Confocal microscopy was performed to assess mitochondrial damage and identify release of cytochrome C after treatment. Western blots were used to determine expression of oxidative stress-related and apoptosis-associated protein. Ultrastructural changes in the cell were studied by scanning electron microscopy. Results DVDMS showed higher autofluorescence intensity and singlet oxygen production efficiency compared with other photosensitizers in both cancerous and normal cells. Compared with hematoporphyrin, DVDMS-mediated SDT was more cytotoxic in ECA-109 cells. Abundant intracellular ROS was found in the SDT groups, and the cytotoxicity induced by SDT was effectively remitted by ROS scavengers. DVDMS located mainly to the mitochondria of ECA-109 cells, which were seriously damaged after exposure to SDT. Release of cytochrome C, an increased rate of apoptosis, and activated apoptosis protein were detected in the SDT group. In addition, relatively severe cell damage was observed on scanning electron microscopy after treatment with DVDMS and SDT. Conclusion These results suggest that DVDMS could be activated by ultrasound, and that DVDMS mediates SDT-induced mitochondrial-dependent apoptosis in ECA-109 cells via production of ROS.

Wang, Haiping; Wang, Xiaobing; Zhang, Shaoliang; Wang, Pan; Zhang, Kun; Liu, Quanhong

2014-01-01

272

The production of reactive oxygen species by irradiated camphorquinone-related photosensitizers and their effect on cytotoxicity.  

PubMed

Camphorquinone (CQ) is widely used as an initiator in modern light-cured resin systems but there are few reports about its effects on living cells. To clarify the mechanism of photosensitizer-induced cytotoxicity, the production of initiator radicals and subsequent reactive oxygen species (ROS) by CQ, benzil (BZ), benzophenone (BP), 9-fluorenone (9-F) in the presence of the reducing agent (2-dimethylaminoethyl methacrylate or N,N-dimethyl-p-toluidine, DMT) with visible-light irradiation was examined in a cell or cell-free system. Initiator radical production was estimated by the reduction rate of 1,1-diphenyl-2-picrylhydrazyl and by the conversion of poly-triethyleneglycol dimethacrylate; the results indicated that CQ/DMT had the highest activity among them. The cytotoxic effects of the photosensitizers on both human submandibular gland (HSG) adenocarcinoma cell line and primary human gingival fibroblast (HGF) showed that the 50% toxic concentration (TC(50)) declined in the order: CQ>BP>9-F>BZ. ROS produced in HSG or HGF cells by elicited, irradiated photosensitizers were evaluated in two different assays, one using adherent cell analysis and sorting cytometry against adherent cells and the other, flow cytometry against floating cells, with fluorescent probes. ROS production was dose- and time- dependent, and declined in the order: BZ>9-F>BP>CQ. Cytotoxic activity was correlated with the amount of ROS. Cytotoxicity and ROS generation in HGF cells was significantly lower than in HSG cells. ROS induced by aliphatic ketones (CQ) were efficiently scavenged by hydroquinone and vitamin E, whereas those by aromatic ketones (9-F) were diminished by mannitol and catalase, suggesting that OH radicals were involved in ROS derived from 9-F. A possible link between the cytotoxic activity and ROS is suggested. PMID:11286804

Atsumi, T; Iwakura, I; Fujisawa, S; Ueha, T

2001-05-01

273

The chlorinated AHR ligand 3,3?,4,4?,5-pentachlorobiphenyl (PCB126) promotes reactive oxygen species (ROS) production during embryonic development in the killifish ( Fundulus heteroclitus)  

Microsoft Academic Search

Exposure to dioxin-like chemicals that activate the aryl hydrocarbon receptor (AHR) can result in increased cellular and tissue production of reactive oxygen species (ROS). Little is known of these effects during early fish development. We used the fish model, Fundulus heteroclitus, to determine if the AHR ligand and pro-oxidant 3,3?,4,4?,5-pentachlorobiphenyl (PCB126) can increase ROS production during killifish development, and to

Xabier Arzuaga; Deena Wassenberg; Richard Di Giulio; Adria Elskus

2006-01-01

274

FcRI- and Fc Receptor-Mediated Production of Reactive Oxygen Species by Mast Cells Is Lipoxygenase and Cyclooxygenase-Dependent and NADPH Oxidase-Independent1  

Microsoft Academic Search

We investigated the enzymes responsible for FcRI-dependent production of reactive oxygen species (ROS) and the influence of ROS on mast cell secretory responses. 5-Lipoxygenase (5-LO) was the primary enzyme involved in ROS production by human mast cells (huMC) and mouse bone marrow-derived mast cells (mBMMC) following FcRI aggregation because incubation with 5-LO inhibitors (AA861, nordihydroguaiaretic acid, zileuton) but not a

Emily J. Swindle; John W. Coleman; Frank R. DeLeo; Dean D. Metcalfe

2007-01-01

275

Forward Hadron Production in Muon Deep Inelastic Scattering at 490 GEV from Deuterium and Xenon  

Microsoft Academic Search

This thesis presents measurements of the energy fraction z and transverse momentum of the final state charged hadrons in muon deep inelastic scattering at 490 GeV from deuterium and xenon targets. The measurements were made as part of Experiment 665 at Fermilab. The ratio of the forward hadron multiplicity between the two nuclei shows that at large transfer energy, upsilon

Alexandro F. Salvarani

1991-01-01

276

Phenylethynyl reactive diluents  

NASA Technical Reports Server (NTRS)

A composition of matter having a specified general structure is employed to terminate a nucleophilic reagent, resulting in the exclusive production of phenylethynyl terminated reactive oligomers which display unique thermal characteristics. A reactive diluent having a specified general structure is employed to decrease the melt viscosity of a phenylethynyl terminated reactive oligomer and to subsequently react with to provide a thermosetting material of enhanced density. These materials have features which make them attractive candidates for use as composite matrices and adhesives.

Bryant, Robert G. (inventor.); Jensen, Brian J. (inventor.); Hergenrother, Paul M. (inventor.)

1995-01-01

277

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

2013-01-01

278

Lanthanum ions intervened in enzymatic production and elimination of reactive oxygen species in leaves of rice seedlings under cadmium stress.  

PubMed

Rare earth elements at proper concentrations were observed to alleviate heavy metal stress. However, the potential mechanisms of alleviation are not clear. Thus, the present study focused on the mechanisms of lanthanum (La) ions on the generation and elimination of reactive oxygen species (ROS) production in leaves of rice seedlings hydroponically cultivated in 30?µM cadmium chloride (CdCl2 ) for 2 d. Results showed that the decline of superoxide (O2 ?·?(-) ) or hydrogen peroxide (H2 O2 ) was attributed not only to the decreased expressions of nicotinamide adenine dinucleotide phosphate oxidases-related gene, protein synthesis, and isozymes, but also to the decrease of xanthine oxidase, diamine oxidase, and guaiacol peroxidases isozymes and activities. Genes and isozymes related to superoxide dismutase, catalase, and ascorbate peroxidase were also differentially upregulated to control ROS accumulation when proper concentrations of La were combined with 30?µM Cd. Based on the results, one may conclude that La at proper concentrations not only limited the generation of O2 ?·?(-) and H2 O2 from the enzymatic sources but also promoted the elimination of O2 ?·?(-) and H2 O2 via the upregulating expressions of antioxidant enzyme-related genes and activities in the rice seedling's leaves under Cd stress. Environ Toxicol Chem 2014;33:1656-1664. © 2014 SETAC. PMID:24753051

Wang, Cheng-Run; Wang, Qin-Ying; Tian, Yuan; Zhang, Ji-Feng; Li, Zhi-Xiao; Cao, Peng; Zhu, Mei; Li, Ting-Ting

2014-07-01

279

Reactivity of Tannic Acid with Common Corrosion Products and Its Influence on the Hydrolysis of Iron in Alkaline Solutions  

NASA Astrophysics Data System (ADS)

To ascertain the role of tannic acid in the anticorrosive protection of steels, the reaction between 5% tannic acid aqueous solutions with lepidocrocite, goethite, superparamagnetic goethite, akaganeite, poorly crystalline maghemite, magnetite and hematite was studied using color changes, infrared and Mössbauer spectroscopy. After three months of interaction with lepidocrocite, the formation of an iron tannate complex was detected by its dark blue color and confirmed by infrared and Mössbauer analysis. Evidence for the chemical transformation was obtained for goethite in nanoparticles and poorly crystalline maghemite after reaction for six months. The other iron compounds do not transform to another oxide or phase upon treatment with the tannic acid solution. These results showed that lepidocrocite is the most reactive phase and that the size and degree of crystallinity have strong influence on the formation of the tannate complexes. The precipitation of iron phases from alkaline solutions of iron (II) sulfate heptahydrate containing different amount of tannic acid and potassium nitrate as oxidative agent was also studied. Mössbauer and infrared results show that in the absence of tannic acid some common rust components are obtained (viz. goethite, superparamagnetic goethite, maghemite and non-stoichiometric magnetite). The presence of 0.1% tannic acid in a low alkalinity solution results in the precipitation of iron oxyhydroxides and some iron tannates. Concentrations of 1% tannic acid are required for the formation of the tannates complexes as main reaction product.

Jaén, J. A.; Araúz, E. Y.; Iglesias, J.; Delgado, Y.

2003-06-01

280

Hepatocarcinogenesis in hepatitis C: HCV shrewdly exacerbates oxidative stress by modulating both production and scavenging of reactive oxygen species.  

PubMed

Persistent infection with hepatitis C virus (HCV) is a major risk for the development of hepatocellular carcinoma (HCC). One of the characteristics of HCV infection is the unusual augmentation of oxidative stress, which is exacerbated by iron accumulation in the liver, as observed frequently in hepatitis C patients. Using a transgenic mouse model, in which HCC develops late in life after the preneoplastic steatosis stage, the core protein of HCV was shown to induce the overproduction of reactive oxygen species (ROS) in the liver. In excessive generation of ROS, HCV affects the steady-state levels of a mitochondrial protein chaperone, i.e. prohibitin, leading to an impaired function of the mitochondrial respiratory chain with the overproduction of ROS. Insulin resistance and hepatic steatosis, which frequently accompany HCV infection, exacerbate ROS production. On the other hand, HCV compromises some of the antioxidant systems, including heme oxygenase-1 and NADH dehydrogenase quinone 1, resulting in the provocation of oxidative stress, together with ROS overproduction, in the liver with HCV infection. Thus, HCV infection not only induces ROS but also hampers the antioxidant system in the liver, thereby exacerbating oxidative stress that would facilitate hepatocarcinogenesis. Combination with the other activated pathway, including an alteration in the intracellular signaling cascade of MAP kinase, along with HCV-associated disturbances in lipid and glucose metabolism would lead to the unusual mode of hepatocarcinogenesis, i.e. very frequent and multicentric development of HCC, in persistent HCV infection. PMID:22212930

Fujinaga, Hidetake; Tsutsumi, Takeya; Yotsuyanagi, Hiroshi; Moriya, Kyoji; Koike, Kazuhiko

2011-01-01

281

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

2013-02-01

282

Dual Oxidase Maturation factor 1 (DUOXA1) overexpression increases reactive oxygen species production and inhibits murine muscle satellite cell differentiation  

PubMed Central

Background Dual oxidase maturation factor 1 (DUOXA1) has been associated with the maturation of the reactive oxygen species (ROS) producing enzyme, dual oxidase 1 (DUOX1) in the adult thyroid. However, ROS have also been implicated in the development of several tissues. We found that activated muscle satellite cells and primary myoblasts isolated from mice express robust levels of DUOXA1 and that its levels are altered as cells differentiate. Results To determine whether DUOXA1 levels affect muscle differentiation, we used an adenoviral construct (pCMV5-DUOXA1-GFP) to drive constitutive overexpression of this protein in primary myoblasts. High levels of DUOXA1 throughout myogenesis resulted in enhanced H2O2 production, fusion defects, reduced expression of early (myogenin) and late (myosin heavy chain) markers of differentiation, and elevated levels of apoptosis compared to control cells infected with an empty adenoviral vector (pCMV5-GFP). DUOXA1 knockdown (using a DUOXA1 shRNA construct) resulted in enhanced differentiation compared to cells subjected to a control shRNA, and subjecting DUOXA1 overexpressing cells to siRNAs targeting DUOX1 or apoptosis signal-regulating kinase 1 (ASK1) rescued the phenotype. Conclusions This study represents the first to demonstrate the importance of DUOXA1 in skeletal muscle myoblasts and that DUOXA1 overexpression in muscle stem cells induces apoptosis and inhibits differentiation through DUOX1 and ASK1.

2014-01-01

283

Changes in reactive oxygen species (ROS) production in rat brain during global perinatal asphyxia: an ESR study.  

PubMed

A large body of evidence suggests that the production of reactive oxygen species (ROS) can play an important role in ischemic neuronal injury. However any studies has been performed in hypoxic conditions. In the present experiments we studied using electron spin resonance (ESR) techniques the ROS release in neostriatum of newborn rats subjected to acute perinatal asphyxia (PA) followed by various periods of reoxygenation. Pregnant rats' uteri still containing foetuses were taken out and subjected to PA by immersion in a 37 degrees C water bath during the following periods of time: 5, 10, 15, 19 and 20 min. After performing PA, animals were recovered and ROS measured after 0, 5, 15, 30 or 60 min of reoxygenation. Then, pups were sacrificed, their neostriatum removed and homogenised with N-tert.-butyl-alpha-phenylnitrone (PBN) and diethylenetriamine-pentacetic acid (DPTA) in phosphate-buffered saline (PBS) and the formed complexes were extracted with ethyl acetate an analysed using an X-band ESR spectrometer. A significant release of ROS was detected at 19 and 20 min of PA after 5 min of reoxygenation. These data provide strong evidence that ROS could be involved in neuronal damage during PA. PMID:11578613

Capani, F; Loidl, C F; Aguirre, F; Piehl, L; Facorro, G; Hager, A; De Paoli, T; Farach, H; Pecci-Saavedra, J

2001-09-28

284

MuRF1 activity is present in cardiac mitochondria and regulates reactive oxygen species production in vivo.  

PubMed

MuRF1 is a previously reported ubiquitin-ligase found in striated muscle that targets troponin I and myosin heavy chain for degradation. While MuRF1 has been reported to interact with mitochondrial substrates in yeast two-hybrid studies, no studies have identified MuRF1's role in regulating mitochondrial function to date. In the present study, we measured cardiac mitochondrial function from isolated permeabilized muscle fibers in previously phenotyped MuRF1 transgenic and MuRF1-/- mouse models to determine the role of MuRF1 in intermediate energy metabolism and ROS production. We identified a significant decrease in reactive oxygen species production in cardiac muscle fibers from MuRF1 transgenic mice with increased ?-MHC driven MuRF1 expression. Increased MuRF1 expression in ex vivo and in vitro experiments revealed no alterations in the respiratory chain complex I and II function. Working perfusion experiments on MuRF1 transgenic hearts demonstrated significant changes in glucose oxidation. This is an factual error as written; however, total oxygen consumption was decreased. This data provides evidence for MuRF1 as a novel regulator of cardiac ROS, offering another mechanism by which increased MuRF1 expression may be cardioprotective in ischemia reperfusion injury, in addition to its inhibition of apoptosis via proteasome-mediate degradation of c-Jun. The lack of mitochondrial function phenotype identified in MuRF1-/- hearts may be due to the overlapping interactions of MuRF1 and MuRF2 with energy regulating proteins found by yeast two-hybrid studies reported here, implying a duplicity in MuRF1 and MuRF2's regulation of mitochondrial function. PMID:24733503

Mattox, Taylor A; Young, Martin E; Rubel, Carrie E; Spaniel, Carolyn; Rodríguez, Jessica E; Grevengoed, Trisha J; Gautel, Mathias; Xu, Zhelong; Anderson, Ethan J; Willis, Monte S

2014-06-01

285

A Novel Nontoxic Inhibitor of the Activation of NADPH Oxidase Reduces Reactive Oxygen Species Production in Mouse LungS?  

PubMed Central

1-Hexadecyl-3-trifluoroethylglycero-sn-2-phosphomethanol (MJ33) is a fluorinated phospholipid analog that inhibits the phospholipase A2 (PLA2) activity of peroxiredoxin 6 (Prdx6). Prdx6 PLA2 activity is required for activation of NADPH oxidase 2 and subsequent generation of reactive oxygen species (ROS). In vitro, MJ33 inhibited agonist-stimulated production of ROS by the isolated perfused mouse lung, lung microvascular endothelial cells, and polymorphonuclear leukocytes. MJ33 (0.02–0.5 µmol MJ33/kg body weight) in mixed unilamellar liposomes was administered to C57BL/6 mice by either intratracheal (i.t.) or i.v. routes. Lung MJ33 content, measured by liquid chromatography/mass spectroscopy, showed uptake of 67–87% of the injected dose for i.t. and 23–42% for i.v. administration at 4 hours postinjection. PLA2 activity of lung homogenates was markedly inhibited (>85%) at 4 hours postadministration. Both MJ33 content and PLA2 activity gradually returned to near control levels over the subsequent 24–72 hours. Mice treated with MJ33 at 12.5–25 µmol/kg did not show changes (compared with control) in clinical symptomatology, body weight, hematocrit, and histology of lung, liver, and kidney during a 30- to 50-day observation period. Thus, the toxic dose of MJ33 was >25 µmol/kg, whereas the PLA2 inhibitory dose was approximately 0.02 µmol/kg, indicating a high margin of safety. MJ33 administered to mice prior to lung isolation markedly reduced ROS production and tissue lipid and protein oxidation during ischemia followed by reperfusion. Thus, MJ33 could be useful as a therapeutic agent to prevent ROS-mediated tissue injury associated with lung inflammation or in harvested lungs prior to transplantation.

Lee, Intae; Dodia, Chandra; Chatterjee, Shampa; Zagorski, John; Mesaros, Clementina; Blair, Ian A.; Feinstein, Sheldon I.; Jain, Mahendra

2013-01-01

286

A novel nontoxic inhibitor of the activation of NADPH oxidase reduces reactive oxygen species production in mouse lung.  

PubMed

1-Hexadecyl-3-trifluoroethylglycero-sn-2-phosphomethanol (MJ33) is a fluorinated phospholipid analog that inhibits the phospholipase A2 (PLA2) activity of peroxiredoxin 6 (Prdx6). Prdx6 PLA2 activity is required for activation of NADPH oxidase 2 and subsequent generation of reactive oxygen species (ROS). In vitro, MJ33 inhibited agonist-stimulated production of ROS by the isolated perfused mouse lung, lung microvascular endothelial cells, and polymorphonuclear leukocytes. MJ33 (0.02-0.5 µmol MJ33/kg body weight) in mixed unilamellar liposomes was administered to C57BL/6 mice by either intratracheal (i.t.) or i.v. routes. Lung MJ33 content, measured by liquid chromatography/mass spectroscopy, showed uptake of 67-87% of the injected dose for i.t. and 23-42% for i.v. administration at 4 hours postinjection. PLA2 activity of lung homogenates was markedly inhibited (>85%) at 4 hours postadministration. Both MJ33 content and PLA2 activity gradually returned to near control levels over the subsequent 24-72 hours. Mice treated with MJ33 at 12.5-25 µmol/kg did not show changes (compared with control) in clinical symptomatology, body weight, hematocrit, and histology of lung, liver, and kidney during a 30- to 50-day observation period. Thus, the toxic dose of MJ33 was >25 µmol/kg, whereas the PLA2 inhibitory dose was approximately 0.02 µmol/kg, indicating a high margin of safety. MJ33 administered to mice prior to lung isolation markedly reduced ROS production and tissue lipid and protein oxidation during ischemia followed by reperfusion. Thus, MJ33 could be useful as a therapeutic agent to prevent ROS-mediated tissue injury associated with lung inflammation or in harvested lungs prior to transplantation. PMID:23475902

Lee, Intae; Dodia, Chandra; Chatterjee, Shampa; Zagorski, John; Mesaros, Clementina; Blair, Ian A; Feinstein, Sheldon I; Jain, Mahendra; Fisher, Aron B

2013-05-01

287

Increase in reactive oxygen species production and phagocytic activity of polymorphonuclear neutrophils stimulated by preirradiated hematoporphyrin-derivative solution  

NASA Astrophysics Data System (ADS)

We have studied the influence of preirradiated by visible light hematoporphyrin derivative (HpD) solution in PBS on the production of reactive oxygen species (ROS) and phagocytosis of latex particles by rat peritoneal polymorphonuclear neutrophils (PMN), and also on the delayed type hypersensitivity reaction (DTH) to sheep red blood cells in mice. The release of ROS and phagocytic activity were observed by means of registration of the luminol- enhanced chemiluminescence (ChL) in the absence and the in the presence of latex particles. Non-irradiated HpD did not influence neither spontaneous ChL response, nor latex- activated. HpD preirradiated by 135 J/m2 did not affect spontaneous, but increased latex-activated ChL response by 20 percent. This fact indicates an increase in PMN phagocytic activity under the treatment with preirradiated HpD. Increase in preirradiation fluence up to 8.1 kJ/m2 resulted in significant enhancement of spontaneous ChL and inhibition of latex-activated ChL response of PMN. Results of spectroscopic analysis showed negligible decease in HpD Soret band after preirradiation of HpD by the highest fluences used in this study. We could not detect any significant photoproduct formation by differential absorption spectroscopy. Earlier, we have propose the photoinduced aggragation as one of the possible mechanisms of photodegradation of aqueous porphyrin solutions. In all probability, the increase in ROS production by PMN, treated with preirradiated HpD can be attributed to the phagocytosis of aggregates formed. It is possible that ROS can influence directly the DTH-effector cells leading to the observed decrease in DTH reaction level.

Melnikova, Vladislava; Bezdetnaya, Lina N.; Belitchenko, Irina; Kyagova, Alla A.; Colosetti, Pascal; Potapenko, Alexander Y.; Guillemin, Francois H.

1997-05-01

288

Polyphenols can inhibit furin in vitro as a result of the reactivity of their auto-oxidation products to proteins.  

PubMed

Methods using fluorogenic peptide substrates have been proposed for screening of proprotein convertase (PC) inhibitors and they are attractive since they offer the advantage of being sensitive, cost-effective and susceptible to miniaturization. Several polyphenols, including epigallocatechin gallate ((-)EGCG), the main component of green tea, and quercetin, widely distributed in fruit and vegetables, however, led to false positive results when fluorogenic peptide substrates were used. Processing of genuine furin substrates was not inhibited by these polyphenols. In the present study, these discordant effects of (-)EGCG on the PC furin were studied. While quercetin can form aggregates in solution, aggregate-based promiscuous inhibition could be ruled out as underlying mechanism for (-)EGCG. Hydrogen peroxide production, from auto-oxidation, was too low to be a major factor but appeared associated to furin inhibition, suggesting a role for other auto-oxidation products. Since the instability of catechins is related to their electrophilic character, we tested the nucleophilic substance glutathione for stabilization. Indeed glutathione reduced furin inhibition and (-)EGCG binding to furin and serum albumin as shown by redox-cycling staining. Catechins, therefore, seem to form reactive compounds and this should be taken into account in screening assays. Adding glutathione to the detergent-based assay, as used in these studies to measure furin processing activity, strongly reduced inhibition by a number of polyphenols (catechins, gallic acid and quercetin), while the effect on the genuine inhibitor nona-D-arginine remained unchanged. In conclusion: the combined use of detergent and glutathione in the screening assay for furin inhibitors improves the predictive value. PMID:23231348

Zhu, J; Van de Ven, W J M; Verbiest, T; Koeckelberghs, G; Chen, C; Cui, Y; Vermorken, A J M

2013-02-01

289

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

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

2013-01-01

291

Reactivation of Desensitized Formyl Peptide Receptors by Platelet Activating Factor: A Novel Receptor Cross Talk Mechanism Regulating Neutrophil Superoxide Anion Production  

PubMed Central

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.

Andreasson, Emil; Christenson, Karin; Karlsson, Anna; Bylund, Johan; Dahlgren, Claes

2013-01-01

292

Coarse-grained potential analysis of neutron-proton and proton-proton scattering below the pion production threshold  

NASA Astrophysics Data System (ADS)

Using the ?-shell representation we present a successful fit to neutron-proton and proton-proton scattering data below the pion production threshold. A detailed overview of the theory necessary to calculate observables with this potential is presented. A new data selection process is used to obtain the largest mutually consistent data base. The analysis includes data within the years 1950 to 2013. Using 46 parameters we obtain ?2/Ndata=1.04 with Ndata=6713 including normalization data. Phase shifts with error bars are provided.

Pérez, R. Navarro; Amaro, J. E.; Arriola, E. Ruiz

2013-12-01

293

Single transverse-spin asymmetry for D-meson production in semi-inclusive deep inelastic scattering  

SciTech Connect

We study the single transverse-spin asymmetry for open charm production in the semi-inclusive lepton-hadron deep inelastic scattering. We calculate the asymmetry in terms of the QCD collinear factorization approach for D mesons at high enough P{sub hperpendicular} and find that the asymmetry is proportional to the twist-three trigluon correlation function in the proton. With a simple model for the trigluon correlation function, we estimate the asymmetry for both COMPASS and eRHIC kinematics and discuss the possibilities of extracting the trigluon correlation function in these experiments.

Kang Zhongbo; Qiu Jianwei [Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011 (United States)

2008-08-01

294

First measurements of jet production rates in deep-inelastic lepton-proton scattering  

Microsoft Academic Search

The first measurements of forward multijet rates in deep-inelastic lepton scattering are presented. Data were taken with a 490-GeV muon beam incident on a hydrogen target. The jets were defined using the gade algorithm. The measured rates are presented as a function of the jet resolution parameter ycut, and as a function of the virtual-photon-proton center-of-momentum energy W, in the

M. R. Adams; S. Aied; P. L. Anthony; M. D. Baker; J. Bartlett; A. A. Bhatti; H. M. Braun; W. Busza; J. M. Conrad; G. Coutrakon; R. Davisson; I. Derado; S. K. Dhawan; W. Dougherty; T. Dreyer; K. Dziunikowska; V. Eckardt; U. Ecker; M. Erdmann; A. Eskreys; J. Figiel; H. J. Gebauer; D. F. Geesaman; R. Gilman; M. C. Green; J. Haas; C. Halliwell; J. Hanlon; D. Hantke; V. W. Hughes; H. E. Jackson; D. E. Jaffe; G. Jancso; D. M. Jansen; S. Kaufman; R. D. Kennedy; H. G. E. Kobrak; S. Krzywdzinski; S. Kunori; J. J. Lord; H. J. Lubatti; D. McLeod; S. Magill; P. Malecki; A. Manz; D. G. Michael; W. Mohr; H. E. Montgomery; J. G. Morfin; R. B. Nickerson; S. O'day; K. Olkiewicz; L. Osborne; V. Papavassiliou; B. Pawlik; F. M. Pipkin; E. J. Ramberg; A. Roeser; J. Ryan; C. W. Salgado; A. Salvarani; H. Schellman; N. Schmitz; K. P. Schueler; H. J. Seyerlein; A. Skuja; G. A. Snow; S. Soeldner-Rembold; P. H. Steinberg; H. E. Stier; P. Stopa; R. A. Swanson; R. Talaga; S. Tentindo-Repond; H.-J. Trost; H. Venkataramania; M. Vidal; M. Wilhelm; J. Wilkes; Richard Wilson; W. Wittek; S. A. Wolbers; T. Zhao

1992-01-01

295

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

Microsoft Academic Search

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 kT 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

S. Chekanov; M. Derrick; S. Magill; S. Miglioranzi; B. Musgrave; J. Repond; R. Yoshida; M. C. K. Mattingly; N. Pavel; A. G. Yagües Molina; 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; A. Polini; 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; K. C. Voss; M. Wang; M. Wlasenko; D. S. Bailey; N. H. Brook; J. E. Cole; G. P. Heath; T. Namsoo; S. Robins; M. Capua; A. Mastroberardino; M. Schioppa; G. Susinno; E. Tassi; J. Y. Kim; K. J. Ma; M. Helbich; Y. Ning; Z. Ren; W. B. Schmidke; F. Sciulli; J. Chwastowski; A. Eskreys; J. Figiel; A. Galas; K. Olkiewicz; P. Stopa; D. Szuba; L. Zawiejski; L. Adamczyk; T. Bo?d; I. Grabowska-Bo?d; D. Kisielewska; A. M. Kowal; J. ?ukasik; M. Przybycie?; L. Suszycki; J. Szuba; A. Kota?ski; W. S?omi?ski; V. Adler; U. Behrens; I. Bloch; K. Borras; G. Drews; J. Fourletova; A. Geiser; D. Gladkov; P. Göttlicher; O. Gutsche; T. Haas; W. Hain; C. Horn; B. Kahle; U. Kötz; H. Kowalski; G. Kramberger; D. Lelas; H. Lim; B. Löhr; R. Mankel; I.-A. Melzer-Pellmann; C. N. Nguyen; D. Notz; A. E. Nuncio-Quiroz; A. Raval; R. Santamarta; U. Schneekloth; G. Wolf; C. Youngman; W. Zeuner; S. Schlenstedt; G. Barbagli; E. Gallo; C. Genta; P. G. Pelfer; A. Bamberger; A. Bamberger; 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; A. Ziegler; C. Collins-Tooth; C. Foudas; R. Gonçalo; K. R. Long; A. D. Tapper; 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; M. Jimenez; L. Labarga; J. del Peso; J. Terrón; M. Zambrana; M. Barbi; F. Corriveau; C. Liu; S. Padhi; M. Plamondon; D. G. Stairs; R. Walsh; C. Zhou; T. Tsurugai; A. Antonov; P. Danilov; B. A. Dolgoshein; V. Sosnovtsev; A. Stifutkin; S. Suchkov; R. K. Dementiev; P. F. Ermolov; L. K. Gladilin; I. I. Katkov; L. A. Khein; I. A. Korzhavina; V. A. Kuzmin; B. B. Levchenko; O. Yu. Lukina; A. S. Proskuryakov; L. M. Shcheglova; D. S. 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; P. D. Allfrey; M. A. Bell; A. M. Cooper; 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; R. Ciesielski; F. Dal Corso; S. Dusini; A. Garfagnini; S. Limentani; A. Longhin; L. Stanco; M. Turcato; E. A. Heaphy; F. Metlica; B. Y. Oh; J. J. Whitmore; Y. Iga; G. D'Agostini; G. Marini; A. Nigro; J. C. Hart; H. Abramowicz; A. Gabareen; S. Kananov; A. Kreisel; A. Levy; M. Kuze; S. Kagawa; T. Tawara; R. Hamatsu; H. Kaji; S. Kitamura; K. Matsuzawa; O. Ota; Y. D. Ri; M. Costa; M. I. Ferrero; V. Monaco; R. Sacchi; A. Solano; M. Arneodo; M. Ruspa; S. Fourletov; T. Koop; J. F. Martin; A. Mirea; J. M. Butterworth; R. Hall-Wilton; T. W. Jones; J. H. Loizides; M. R. Sutton; C. Targett-Adams; M. Wing; J. Ciborowski; P. Kulinski; P. ?u?niak; J. Malka; R. J. Nowak; J. M. Pawlak; J. Sztuk; T. Tymieniecka; A. Tyszkiewicz; A. Ukleja; J. Ukleja; A. F. ?arnecki; M. Adamus; P. Plucinski; Y. Eisenberg; D. Hochman; U. Karshon; M. S. Lightwood; A. Everett; D. Kçira; S. Lammers; L. Li; D. D. Reeder; M. Rosin; P. Ryan; A. A. Savin; W. H. Smith; S. Dhawan; S. Bhadra; C. D. Catterall; Y. Cui; G. Hartner; S. Menary; U. Noor; M. Soares; J. Standage; J. Whyte

2006-01-01

296

Raman scattering and associated fast electron production. Final technical report, April 16, 1984-April 15, 1985  

SciTech Connect

High energy electrons in plasmas have been attributed to various causes including trapping by electron plasma waves created by stimulated Raman scattering. A theory, consistent with experimental results, based on the acceleration of trapped electrons by such electron plasma waves as they propagate in the presence of a density gradient away from the region where they are created is presented. Single particle simulations show accelerating voltages as high as 20 GV/m.

Brooks, R.D.; Pietrzyk, Z.A.

1985-08-01

297

Charged particle production in high Q 2 deep-inelastic scattering at HERA  

Microsoft Academic Search

The average charged track multiplicity and the normalised distribution of the scaled momentum, xp, of charged final state hadrons are measured in deep-inelastic ep scattering at high Q2 in the Breit frame of reference. The analysis covers the range of photon virtuality 100Q220000 GeV2. Compared with previous results presented by HERA experiments this analysis has a significantly higher statistical precision and

F. D. Aaron; A. Aktas; C. Alexa; V. Andreev; B. Antunovic; S. Aplin; A. Asmone; A. Astvatsatourov; S. Backovic; A. Baghdasaryan; 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; M. Deak; Y. de Boer; B. Delcourt; M. Del Degan; J. Delvax; 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. Falkiewicz; P. J. W. Faulkner; L. Favart; A. Fedotov; R. Felst; J. Feltesse; L. Finke; M. Fleischer; A. Fomenko; G. Franke; T. Frisson; E. Gabathuler; 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; M. Jacquet; M. E. Janssen; 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; A. Knutsson; V. Korbel; P. Kostka; M. Kraemer; K. Krastev; J. Kretzschmar; A. Kropivnitskaya; K. Krüger; M. P. J. Landon; W. Lange; G. Laštovi?ka-Medin; P. Laycock; A. Lebedev; G. Leibenguth; V. Lendermann; S. Levonian; G. Li; L. Lindfeld; K. Lipka; A. Liptaj; B. List; J. List; N. Loktionova; R. Lopez-Fernandez; V. Lubimov; A.-I. Lucaci-Timoce; L. Lytkin; A. Makankine; E. Malinovski; P. Marage; Ll. 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; A. Mohamed; F. Moreau; A. Morozov; J. V. Morris; M. U. Mozer; K. Müller; P. Murín; K. Nankov; B. Naroska; Th. 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; Th. Papadopoulou; C. Pascaud; G. D. Patel; H. Peng; E. Perez; D. Perez-Astudillo; A. Perieanu; A. Petrukhin; I. Picuric; S. Piec; D. Pitzl; R. Pla?akyt?; B. Povh; T. Preda; P. Prideaux; V. Radescu; A. J. Rahmat; N. Raicevic; T. Ravdandorj; P. Reimer; C. Risler; E. Rizvi; P. Robmann; B. Roland; R. Roosen; A. Rostovtsev; Z. Rurikova; S. Rusakov; D. Salek; F. Salvaire; D. P. C. Sankey; M. Sauter; E. Sauvan; S. Schmidt; 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; Z. Staykova; M. Steder; B. Stella; J. Stiewe; U. Straumann; D. Sunar; T. Sykora; V. Tchoulakov; G. Thompson; P. D. Thompson; T. Toll; F. Tomasz; T. H. Tran; D. Traynor; T. N. Trinh; P. Truöl; I. Tsakov; B. Tseepeldorj; G. Tsipolitis; I. Tsurin; J. Turnau; E. Tzamariudaki; K. Urban; D. Utkin; A. Valkárová; C. Vallée; P. Van Mechelen; A. Vargas Trevino; Y. Vazdik; S. Vinokurova; V. Volchinski; G. Weber; R. Weber; D. Wegener; C. Werner; M. Wessels; Ch. Wissing; R. Wolf; E. Wünsch; S. Xella; V. Yeganov; J. Žá?ek; J. Zálešák; Z. Zhang; A. Zhelezov; Y. C. Zhu; T. Zimmermann; H. Zohrabyan; F. Zomer

2007-01-01

298

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

Microsoft Academic Search

Wearthering steels treated with and without zinc phosphate solution were exposed to atmosphere for 15 years and rust layers\\u000a produced on the steels were analysed by scattering Mssbauer spectrometry (CEMS and XMS). ?-FeOOH, fine ?-FeOOH, 5Fe2O39H2O, ?-Fe2O3 and Fe3O4 were identified to be present in the rust formed on the steel without phosphate coating. Large particles of ?-Fe2O3 and Fe3O4

Kiyoshi Nomura; Yusuke Ujihira

1986-01-01

299

Soft X-ray production by photon scattering in pulsating binary neutron star sources  

NASA Technical Reports Server (NTRS)

A new mechanism is proposed as a source of soft (less than 1 keV) radiation in binary pulsating X-ray sources, in the form of photon scattering which leaves the electron in an excited Landau level. In a plasma with parameters typical of such sources, the low-energy X-ray emissivity of this mechanism far exceeds that of bremsstrahlung. This copious source of soft photons is quite adequate to provide the seed photons needed to explain the power-law hard X-ray spectrum by inverse Comptonization on the hot electrons at the base of the accretion column.

Bussard, R. W.; Meszaros, P.; Alexander, S.

1985-01-01

300

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

2013-02-01

301

Increased Reactive Oxygen Species Production in the Brain After Repeated Low-Dose Pesticide Paraquat Exposure in Rats. A Comparison with Peripheral Tissues  

Microsoft Academic Search

The pesticide paraquat (PQ) was found to be a suitable xenobiotic to model Parkinson’s disease. The reactive oxygen species\\u000a (ROS) production was suggested to be the main cause of PQ toxicity but very few evidences were found for its generation in\\u000a the brain in vivo after ip administration. We compared the effects of PQ-induced ROS generation between the brain structures

Katarzyna Kuter; Przemys?aw Nowak; Krystyna Go?embiowska; Krystyna Ossowska

2010-01-01

302

Biochemical analysis of reactive oxygen species production and antioxidative responses in unripe avocado ( Persea americana Mill var Hass) fruits in response to wounding  

Microsoft Academic Search

We analyzed the production of reactive oxygen species (ROS) and of detoxifying enzymes and enzymes of the ascorbate (ASC)\\u000a acid cycle in avocado fruit (Pesea Americana Mill cv Hass) in response to wounding. The levels of superoxide anion (O2\\u000a ?), hydroxyl radicals (OH.) and hydrogen peroxide (H2O2) increased at 15 min and 2 and 15 h post-wounding. Peroxidase (POD) activity had increased

E. Castro-Mercado; Y. Martinez-Diaz; N. Roman-Tehandon; E. Garcia-Pineda

2009-01-01

303

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  

Microsoft Academic Search

Succinate:quinone reductase (SQR) of Complex II, occupying a unique central point in the mitochondrial respiratory system\\u000a as a major source of electrons driving reactive oxygen species (ROS) production, is an ideal pharmaceutical target for modulating\\u000a ROS levels in normal cells to prevent oxidative stress-induced damage or increase ROS in cancer cells, inducing cell death.\\u000a Value of drugs like diazoxide to

Stephen J. Ralph; Rafael Moreno-Sánchez; Jiri Neuzil; Sara Rodríguez-Enríquez

304

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

305

Electron scattering on the Hoyle state and carbon production in stars  

SciTech Connect

High-resolution inelastic electron scattering experiments were performed at the S-DALINAC for a precise determination of the partial pair width {gamma}{sub {pi}} of the second J{sup {pi}} = 0{sup +} state, the so-called Hoyle state, in {sup 12}C. Results for the monopole matrix element (directly related to {gamma}{sub {pi}}) from a nearly model-independent analysis based on an extrapolation of low-q data to zero momentum transfer are presented. Additionally, a Fourier-Bessel analysis of the transition form factor is discussed. The combined result of both methods leads to a pair width {gamma}{sub {pi}}62.2(10) {mu}eV.

Chernykh, M.; Neumann-Cosel, P. von; Richter, A. [Institut fuer Kernphysik, Technische Universitaet Darmstadt, D-64289 Darmstadt (Germany); Blok, H. P. [Department of Physics and Astronomy, Vrije Universiteit, 1081 HV Amsterdam (Netherlands); Feldmeier, H.; Neff, T. [Gesellschaft fuer Schwerionenforschung (GSI), D-64291 Darmstadt (Germany)

2009-01-28

306

On the temperature dependence of organic reactivity, nitrogen oxides, ozone production, and the impact of emission controls in San Joaquin Valley, California  

NASA Astrophysics Data System (ADS)

The San Joaquin Valley (SJV) experiences some of the worst ozone air quality in the US, frequently exceeding the California 8 h standard of 70.4 ppb. To improve our understanding of trends in the number of ozone violations in the SJV, we analyze observed relationships between organic reactivity, nitrogen oxides (NOx), and daily maximum temperature in the southern SJV using measurements made as part of California at the Nexus of Air Quality and Climate Change in 2010 (CalNex-SJV). We find the daytime speciated organic reactivity with respect to OH during CalNex-SJV has a temperature-independent portion with molecules typically associated with motor vehicles being the major component. At high temperatures, characteristic of days with high ozone, the largest portion of the total organic reactivity increases exponentially with temperature and is dominated by small, oxygenated organics and molecules that are unidentified. We use this simple temperature classification to consider changes in organic emissions over the last and next decade. With the CalNex-SJV observations as constraints, we examine the sensitivity of ozone production (PO3) to future NOx and organic reactivity controls. We find that PO3 is NOx-limited at all temperatures on weekends and on weekdays when daily maximum temperatures are greater than 29 °C. As a consequence, NOx reductions are the most effective control option for reducing the frequency of future ozone violations in the southern SJV.

Pusede, S. E.; Gentner, D. R.; Wooldridge, P. J.; Browne, E. C.; Rollins, A. W.; Min, K.-E.; Russell, A. R.; Thomas, J.; Zhang, L.; Brune, W. H.; Henry, S. B.; DiGangi, J. P.; Keutsch, F. N.; Harrold, S. A.; Thornton, J. A.; Beaver, M. R.; St. Clair, J. M.; Wennberg, P. O.; Sanders, J.; Ren, X.; VandenBoer, T. C.; Markovic, M. Z.; Guha, A.; Weber, R.; Goldstein, A. H.; Cohen, R. C.

2014-04-01

307

Troubleshooting the dichlorofluorescein assay to avoid artifacts in measurement of toxicant-stimulated cellular production of reactive oxidant species  

PubMed Central

Introduction The dichlorofluorescein (DCF) assay is a popular method for measuring cellular reactive oxidant species (ROS). Although caveats have been reported with the DCF assay and other compounds, the potential for artifactual results due to cell-free interactions between the DCF compound and toxicants has hardly been explored. We evaluated the utility of the DCF assay for measuring ROS generation by the toxicants mono-(2-ethylhexyl) phthalate (MEHP), and tetrabromobisphenol A (TBBPA). Methods DCF fluorescence was measured spectrofluorometrically after a 1-h incubation of toxicants with 6-carboxy-2?,7?-dichlorodihydrofluorescein diacetate (carboxy-H2DCFDA). MEHP was incubated with carboxy-H2DCFDA in cell-free solutions of Hank’s buffered salt solution (HBSS), or in Royal Park Memorial Institute (RPMI) medium with or without fetal bovine serum. TBBPA was incubated with carboxy-H2DCFDA in cell-free HBSS and with human trophoblast cells (HTR8/SVneo cells). Results MEHP did not increase fluorescence in solutions of carboxy-H2DCFDA in HBSS or RPMI medium without serum. However, MEHP (90 and 180 ?M) increased DCF fluorescence in cell-free RPMI medium containing serum. Furthermore, serum-free and cell-free HBSS solutions containing 25 ?M TBBPA exhibited concentration-dependent increased fluorescence with 5–100 ?M carboxy-H2DCFDA (p<0.05), but not 1 ?M carboxy-H2DCFDA. In addition, we observed increased fluorescence in HTR8/SVneo cell cultures exposed to TBBPA (0.5–25 ?M) (p<0.05), as we had observed in cell-free buffer. Discussion MEHP demonstrated an interaction with serum in cell-free generation of DCF fluorescence, whereas TBBPA facilitated conversion of carboxy-H2DCFDA to the fluorescent DCF moiety in the absence of serum. Because TBBPA increased fluorescence in the absence of cells, the increased DCF fluorescence observed with TBBPA in the presence of cells cannot be attributed to cellular ROS and may, instead, be the result of chemical activation of carboxy-H2DCFDA to the fluorescent DCF moiety. These data illustrate the importance of including cell-free controls when using the DCF assay to study toxicant-stimulated cellular production of ROS.

Tetz, Lauren M.; Kamau, Patricia W.; Cheng, Adrienne A.; Meeker, John D.; Loch-Caruso, Rita

2013-01-01

308

Baer-Kouri-Levin-Tobocman equations for reactive scattering: Use of free-wave Green's functions for three finite-mass atom systems  

NASA Astrophysics Data System (ADS)

Recently a method for solving the Baer-Kouri-Levin-Tobocman integral equations was presented and applied to several collinear reactive systems. The method is based on using a distortion potential in the unperturbed Hamiltonian so that the translational part of the Green's function involves distorted elastic wave functions. In this work we report on a solution of these equations without a distortion potential so that the Green's function involves free (asymptotic) translational wave functions. The advantages of using these functions is that a certain amount of computer work is saved because some of the integrations can be carried out analytically. A disadvantage is that the rate of convergence with respect to both vibrational and translational basis functions is slower than when the smooth distortion potential is employed. Two diagnostics of the accuracy of the results are found to be the size of the determinant of coefficients of the simultaneous algebraic equations and symmetry of the R matrix. In addition, it is found that if a distortion potential is used, one should choose it so that the resulting perturbation is made small and of least extent possible. This accelerates convergence of the solution with respect to basis size.

Shima, Y.; Baer, M.; Kouri, D. J.

1986-08-01

309

Hepatocyte Growth Factor Suppresses Production of Reactive Oxygen Species and Release of Eosinophil-Derived Neurotoxin from Human Eosinophils  

Microsoft Academic Search

Background:Reactive oxygen species (ROS) and eosinophilic granule proteins such as eosinophil-derived neurotoxin (EDN) are known to damage bronchial tissue and cause airway hyperresponsiveness (AHR) in asthma. Hepatocyte growth factor (HGF) regulates various biological activities and is known to be a multifunctional factor. In our previous study, we found that HGF suppressed allergic airway inflammation and AHR in a murine model

Wataru Ito; Masahide Takeda; Miyoshi Fujita; Yumiko Kamada; Hikari Kato; Takahito Chiba; Kazutoshi Yamaguchi; Shigeharu Ueki; Hiroyuki Kayaba; Arihiko Kanehiro; Junichi Chihara

2008-01-01

310

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

311

Fracture Reactivation in Chemically Reactive Rock Systems  

NASA Astrophysics Data System (ADS)

Reactivation of existing fractures is a fundamental process of brittle failure that controls the nucleation of earthquake ruptures, propagation and linkage of hydraulic fractures in oil and gas production, and the evolution of fault and fracture networks and thus of fluid and heat transport in the upper crust. At depths below 2-3 km, and frequently shallower, brittle processes of fracture growth, linkage, and reactivation compete with chemical processes of fracture sealing by mineral precipitation, with precipitation rates similar to fracture opening rates. We recently found rates of fracture opening in tectonically quiescent settings of 10-20 ?m/m.y., rates similar to euhedral quartz precipitation under these conditions. The tendency of existing partially or completely cemented fractures to reactivate will vary depending on strain rate, mineral precipitation kinetics, strength contrast between host rock and fracture cement, stress conditions, degree of fracture infill, and fracture network geometry. Natural fractures in quartzite of the Cambrian Eriboll Formation, NW Scotland, exhibit a complex history of fracture formation and reactivation, with reactivation involving both repeated crack-seal opening-mode failure and shear failure of fractures that formed in opening mode. Fractures are partially to completely sealed with crack-seal or euhedral quartz cement or quartz cement fragmented by shear reactivation. Degree of cementation controls the tendency of fractures for later shear reactivation, to interact elastically with adjacent open fractures, and their intersection behavior. Using kinematic, dynamic, and diagenetic criteria, we determine the sequence of opening-mode fracture formation and later shear reactivation. We find that sheared fracture systems of similar orientation display spatially varying sense of slip We attribute these inconsistent directions of shear reactivation to 1) a heterogeneous stress field in this highly fractured rock unit and 2) variations in the degree of fracture cement infill in fractures of same orientation, allowing fractures to reactivate at times when adjacent, more cemented fractures remain dormant. The observed interaction of chemical and mechanical fracture growth and sealing processes in this chemically reactive and heavily deformed rock unit results in a complex fracture network geometry not generally observed in less chemically reactive, shallower crustal environments.

Eichhubl, P.; Hooker, J. N.

2013-12-01

312

Observation of two-jet production in deep inelastic scattering at HERA  

Microsoft Academic Search

A sample of events with two distinct jets, in addition to the proton remnant, has been identified in deep inelastic, neutral current ep interactions recorded at HERA by the ZEUS experiment. For these events, the mass of the hadronic system ranges from 40 to 260 GeV. The salient features of the observed jet production agree with the predictions of higher

M. Derrick; D. Krakauer; S. Magill; B. Musgrave; J. Repond; S. Repond; R. Stanek; R. L. Talaga; J. Thron; F. Arzarello; R. Ayad; 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; F. Ciralli; A. Contin; S. D'Auria; C. del Papa; F. Frasconi; P. Giusti; G. Iacobucci; G. Laurenti; G. Levi; Q. Lin; B. Lisowski; G. Maccarrone; A. Margotti; T. Massam; R. Nania; C. Nemoz; F. Palmonari; G. Sartorelli; R. Timellini; Y. Zamora Garcia; A. Zichichi; A. Bargende; J. Crittenden; H. Dabbous; K. Desch; B. Diekmann; T. Doeker; M. Geerts; G. Geitz; B. Gutjahr; H. Hartmann; D. Haun; K. Heinloth; E. Hilger; H.-P. Jakob; S. Kramarczyk; M. Kückes; A. Mass; S. Mengel; J. Mollen; D. Monaldi; H. Müsch; E. Paul; R. Schattevoy; J.-L. Schneider; R. Wedemeyer; A. Cassidy; D. G. Cussans; N. Dyce; H. F. Fawcett; B. Foster; R. Gilmore; G. P. Heath; M. Lancaster; T. J. Llewellyn; J. Malos; C. J. S. Morgado; R. J. Tapper; S. S. Wilson; R. R. Rau; M. Arneodo; T. Barillari; M. Schioppa; G. Susinno; A. Bernstein; A. Caldwell; I. Gialas; J. A. Parsons; S. Ritz; F. Sciulli; P. B. Straub; L. Wai; S. Yang; J. Chwastowski; A. Dwurazny; A. Eskreys; Z. Jakubowski; B. Niziom; K. Piotrzkowski; M. Zachara; L. Zawiejski; B. Bednarek; P. Borzemski; K. Eskreys; K. Jelen; D. Kisielewska; T. Kowalski; E. Rulikowska-Zarebska; L. Suszycki; J. Zajc; T. Kedzierski; A. Kotanski; M. Przybycien; L. A. T. Bauerdick; U. Behrens; J. K. Bienlein; C. Coldewey; A. Dannemann; G. Drews; P. Erhard; M. Flasinski; I. Fleck; R. Gläser; P. Göttlicher; T. Haas; L. Hagge; W. Hain; D. Hasell; H. Hultschig; G. Jahnen; P. Joos; M. Kasemann; R. Klanner; W. Koch; U. Kötz; H. Kowalski; J. Krüger; J. Labs; A. Ladage; B. Löhr; M. Löwe; D. Lüke; J. Mainusch; O. Manczak; M. Momayezi; J. S. T. Ng; S. Nickel; D. Notz; I. H. Park; K.-U. Pösnecker; M. Rohde; J. Roldán; E. Ros; U. Schneekloth; J. Schroeder; W. Schulz; F. Selonke; E. Stiliaris; E. Tscheslog; T. Tsurugai; F. Turkot; W. Vogel; G. Wolf; C. Youngman; H. J. Grabosch; A. Leich; A. Meyer; C. Rethfeldt; S. Schlenstedt; G. Barbagli; A. Francescato; M. Nuti; P. Pelfer; G. Anzivino; R. Casaccia; S. de Pasquale; S. Qian; L. Votano; A. Bamberger; A. Freidhof; T. Poser; S. Söldner-Rembold; G. Theisen; T. Trefzger; N. H. Brook; P. J. Bussey; A. T. Doyle; J. R. Forbes; V. A. Jamieson; C. Raine; D. H. Saxon; H. Brückmann; G. Gloth; U. Holm; H. Kammerlocher; B. Krebs; T. Neumann; K. Wick; A. Fürtjes; W. Kröger; E. Lohrmann; J. Milewski; M. Nakahata; N. Pavel; G. Poelz; A. Seidman; W. Schott; J. Terron; B. H. Wiik; F. Zetsche; T. C. Bacon; I. Butterworth; C. Markou; D. McQuillan; D. B. Miller; M. M. Mobayyen; A. Prinias; A. Vorvolakos; T. Bienz; H. Kreutzmann; U. Mallik; E. McCliment; M. Roco; M. Z. Wang; P. Cloth; D. Filges; L. Chen; R. Imlay; S. Kartik; H.-J. Kim; R. R. McNeil; W. Metcalf; F. Barreiro; G. Cases; L. Hervás; L. Labarga; J. del Peso; J. F. de Trocóniz; F. Ikraiam; J. K. Mayer; G. R. Smith; F. Corriveau; D. J. Gilkinson; D. S. Hanna; J. Hartmann; L. W. Hung; J. N. Lim; R. Meijer Drees; J. W. Mitchell; P. M. Patel; L. E. Sinclair; D. G. Stairs; R. Ullmann; G. L. Bashindzhagyan; P. F. Ermolov; L. K. Gladilin; Y. A. Golubkov; V. A. Kuzmin; E. N. Kuznetsov; A. A. Savin; A. G. Voronin; N. P. Zotov; S. Bentvelsen; M. Botje; A. Dake; J. Engelen; P. de Jong; M. de Kamps; P. Kooijman; A. Kruse; H. van der Lugt; V. O'dell; A. Tenner; H. Tiecke; H. Uijterwaal; M. Vreeswijk; L. Wiggers; E. de Wolf; R. van Woudenberg; R. Yoshida; B. Bylsma; L. S. Durkin; K. Honscheid; C. Li; T. Y. Ling; K. W. McLean; W. N. Murray; S. K. Park; T. A. Romanowski; R. Seidlein; G. A. Blair; A. Byrne; R. J. Cashmore; A. M. Cooper-Sarkar; R. C. E. Devenish; D. M. Gingrich; P. M. Hallam-Baker; N. Harnew; T. Khatri; K. R. Long; P. Luffman; I. McArthur; P. Morawitz; J. Nash; S. J. P. Smith; N. C. Roocroft; F. F. Wilson; G. Abbiendi; R. Brugnera; R. Carlin; F. dal Corso; M. de Giorgi; U. Dosselli; F. Gasparini; S. Limentani; M. Morandin; M. Posocco; L. Stanco; R. Stroili; C. Voci; J. M. Butterworth; J. Bulmahn; G. Field; B. Y. Oh; J. Whitmore; U. Contino; G. D'Agostini; M. Guida; M. Iori; S. M. Mari; G. Marini; M. Mattioli; A. Nigro; J. C. Hart; N. A. McCubbin; K. Prytz; T. P. Shah; T. L. Short; E. Barberis; N. Cartiglia; C. Heusch; B. Hubbard; J. Leslie; W. Lockman; K. O'Shaughnessy; H. F. Sadrozinski; A. Seiden; E. Badura; J. Biltzinger; H. Chaves; M. Rost; R. J. Seifert; A. H. Walenta; W. Weihs; G. Zech; S. Dagan; A. Levy; D. Zer-Zion; T. Hasegawa; M. Hazumi; T. Ishii; S. Kasai; M. Kuze; Y. Nagasawa; M. Nakao; H. Okuno; K. Tokushuku; T. Watanabe; S. Yamada; M. Chiba; R. Hamatsu; T. Hirose; S. Kitamura; S. Nagayama; Y. Nakamitsu; R. Cirio; M. Costa; M. I. Ferrero; L. Lamberti; S. Maselli; C. Peroni; A. Solano; A. Staiano

1993-01-01

313

Observation of two-jet production in deep inelastic scattering at HERA  

NASA Astrophysics Data System (ADS)

A sample of events with two distinct jets, in addition to the proton remnant, has been identified in deep inelastic, neutral current ep interactions recorded at HERA by the ZEUS experiment. For these events, the mass of the hadronic system ranges from 40 to 260 GeV. The salient features of the observed jet production agree with the predictions of higher order QCD.

Derrick, M.; Krakauer, D.; Magill, S.; Musgrave, B.; Repond, J.; Repond, S.; Stanek, R.; Talaga, R. L.; Thron, J.; Arzarello, F.; Ayad, R.; Bari, G.; Basile, M.; Bellagamba, L.; Boscherini, D.; Bruni, A.; Bruni, G.; Bruni, P.; Cara Romeo, G.; Castellini, G.; Chiarini, M.; Cifarelli, L.; Cindolo, F.; Ciralli, F.; Contin, A.; D'Auria, S.; Del Papa, C.; Frasconi, F.; Giusti, P.; Iacobucci, G.; Laurenti, G.; Levi, G.; Lin, Q.; Lisowski, B.; Maccarrone, G.; Margotti, A.; Massam, T.; Nania, R.; Nemoz, C.; Palmonari, F.; Sartorelli, G.; Timellini, R.; Zamora Garcia, Y.; Zichichi, A.; Bargende, A.; Crittenden, J.; Dabbous, H.; Desch, K.; Diekmann, B.; Doeker, T.; Geerts, M.; Geitz, G.; Gutjahr, B.; Hartmann, H.; Haun, D.; Heinloth, K.; Hilger, E.; Jakob, H.-P.; Kramarczyk, S.; Kückes, M.; Mass, A.; Mengel, S.; Mollen, J.; Monaldi, D.; Müsch, H.; Paul, E.; Schattevoy, R.; Schneider, J.-L.; Wedemeyer, R.; Cassidy, A.; Cussans, D. G.; Dyce, N.; Fawcett, H. F.; Foster, B.; Gilmore, R.; Heath, G. P.; Lancaster, M.; Llewellyn, T. J.; Malos, J.; Morgado, C. J. S.; Tapper, R. J.; Wilson, S. S.; Rau, R. R.; Arneodo, M.; Barillari, T.; Schioppa, M.; Susinno, G.; Bernstein, A.; Caldwell, A.; Gialas, I.; Parsons, J. A.; Ritz, S.; Sciulli, F.; Straub, P. B.; Wai, L.; Yang, S.; Chwastowski, J.; Dwura?ny, A.; Eskreys, A.; Jakubowski, Z.; Niziom?, B.; Piotrzkowski, K.; Zachara, M.; Zawiejski, L.; Bednarek, B.; Borzemski, P.; Eskreys, K.; Jele?, K.; Kisielewska, D.; Kowalski, T.; Rulikowska-Zar?bska, E.; Suszycki, L.; Zaja¸c, J.; K?dzierski, T.; Kota?ski, A.; Przybycie?, M.; Bauerdick, L. A. T.; Behrens, U.; Bienlein, J. K.; Coldewey, C.; Dannemann, A.; Drews, G.; Erhard, P.; Flasi?ski, M.; Fleck, I.; Gläser, R.; Göttlicher, P.; Haas, T.; Hagge, L.; Hain, W.; Hasell, D.; Hultschig, H.; Jahnen, G.; Joos, P.; Kasemann, M.; Klanner, R.; Koch, W.; Kötz, U.; Kowalski, H.; Krüger, J.; Labs, J.; Ladage, A.; Löhr, B.; Löwe, M.; Lüke, D.; Mainusch, J.; Manczak, O.; Momayezi, M.; Ng, J. S. T.; Nickel, S.; Notz, D.; Park, I. H.; Pösnecker, K.-U.; Rohde, M.; Roldán, J.; Ros, E.; Schneekloth, U.; Schroeder, J.; Schulz, W.; Selonke, F.; Stiliaris, E.; Tscheslog, E.; Tsurugai, T.; Turkot, F.; Vogel, W.; Wolf, G.; Youngman, C.; Grabosch, H. J.; Leich, A.; Meyer, A.; Rethfeldt, C.; Schlenstedt, S.; Barbagli, G.; Francescato, A.; Nuti, M.; Pelfer, P.; Anzivino, G.; Casaccia, R.; De Pasquale, S.; Qian, S.; Votano, L.; Bamberger, A.; Freidhof, A.; Poser, T.; Söldner-Rembold, S.; Theisen, G.; Trefzger, T.; Brook, N. H.; Bussey, P. J.; Doyle, A. T.; Forbes, J. R.; Jamieson, V. A.; Raine, C.; Saxon, D. H.; Brückmann, H.; Gloth, G.; Holm, U.; Kammerlocher, H.; Krebs, B.; Neumann, T.; Wick, K.; Fürtjes, A.; Kröger, W.; Lohrmann, E.; Milewski, J.; Nakahata, M.; Pavel, N.; Poelz, G.; Seidman, A.; Schott, W.; Terron, J.; Wiik, B. H.; Zetsche, F.; Bacon, T. C.; Butterworth, I.; Markou, C.; McQuillan, D.; Miller, D. B.; Mobayyen, M. M.; Prinias, A.; Vorvolakos, A.; Bienz, T.; Kreutzmann, H.; Mallik, U.; McCliment, E.; Roco, M.; Wang, M. Z.; Cloth, P.; Filges, D.; Chen, L.; Imlay, R.; Kartik, S.; Kim, H.-J.; McNeil, R. R.; Metcalf, W.; Barreiro, F.; Cases, G.; Hervás, L.; Labarga, L.; del Peso, J.; de Trocóniz, J. F.; Ikraiam, F.; Mayer, J. K.; Smith, G. R.; Corriveau, F.; Gilkinson, D. J.; Hanna, D. S.; Hartmann, J.; Hung, L. W.; Lim, J. N.; Meijer Drees, R.; Mitchell, J. W.; Patel, P. M.; Sinclair, L. E.; Stairs, D. G.; Ullmann, R.; Bashindzhagyan, G. L.; Ermolov, P. F.; Gladilin, L. K.; Golubkov, Y. A.; Kuzmin, V. A.; Kuznetsov, E. N.; Savin, A. A.; Voronin, A. G.; Zotov, N. P.; Bentvelsen, S.; Botje, M.; Dake, A.; Engelen, J.; de Jong, P.; de Kamps, M.; Kooijman, P.; Kruse, A.; van der Lugt, H.; O'Dell, V.; Tenner, A.; Tiecke, H.; Uijterwaal, H.; Vreeswijk, M.; Wiggers, L.; de Wolf, E.; van Woudenberg, R.; Yoshida, R.; Bylsma, B.; Durkin, L. S.; Honscheid, K.; Li, C.; Ling, T. Y.; McLean, K. W.; Murray, W. N.; Park, S. K.; Romanowski, T. A.; Seidlein, R.; Blair, G. A.; Byrne, A.; Cashmore, R. J.; Cooper-Sarkar, A. M.; Devenish, R. C. E.; Gingrich, D. M.; Hallam-Baker, P. M.; Harnew, N.; Khatri, T.; Long, K. R.; Luffman, P.; McArthur, I.; Morawitz, P.; Nash, J.; Smith, S. J. P.; Roocroft, N. C.; Wilson, F. F.; Abbiendi, G.; Brugnera, R.; Carlin, R.; Dal Corso, F.; De Giorgi, M.; Dosselli, U.; Gasparini, F.; Limentani, S.; Morandin, M.; Posocco, M.; Stanco, L.; Stroili, R.; Voci, C.; Butterworth, J. M.; Bulmahn, J.; Field, G.; Oh, B. Y.; Whitmore, J.; Contino, U.; D'Agostini, G.; Guida, M.; Iori, M.; Mari, S. M.; Marini, G.; Mattioli, M.; Nigro, A.; Hart, J. C.; McCubbin, N. A.; Prytz, K.; Shah, T. P.; Short, T. L.; Barberis, E.; Cartiglia, N.; Heusch, C.; Hubbard, B.; Leslie, J.; Lockman, W.; O'Shaughnessy, K.; Sadrozinski, H. F.

1993-05-01

314

Climate and topographic controls on pasture production in a semiarid Mediterranean watershed with scattered tree cover  

NASA Astrophysics Data System (ADS)

Natural grasses in semiarid rangelands constitute an effective protection against soil erosion and degradation, are a source of natural food for livestock and play a critical role in the hydrologic cycle by contributing to the uptake and transpiration of water. However, natural pastures are threatened by land abandonment and the consequent encroachment of shrubs and trees as well as by changing climatic conditions. In spite of their ecological and economic importance, the spatio-temporal variations of pasture production at the decadal to century scales over whole watersheds are poorly known. We used a physics-based, spatially-distributed ecohydrologic model applied to a 99.5 ha semiarid watershed in western Spain to investigate the sensitivity of pasture production to climate variability. The ecohydrologic model was run using a 300 yr long synthetic daily climate dataset generated using a stochastic weather generator. The data set reproduced the range of climatic variations observed under current climate. Results indicated that variation of pasture production largely depended on factors that also determined the availability of soil moisture such as the temporal distribution of precipitation, topography, and tree canopy cover. The latter is negatively related with production, reflecting the importance of rainfall and light interception, as well as water consumption by trees. Valley bottoms and flat areas in the lower parts of the catchment are characterized by higher pasture production. A quantitative assessment of the quality of the simulations showed that ecohydrologic models are a valuable tool to investigate long term (century scale) water and energy fluxes, as well as vegetation dynamics, in semiarid rangelands.

Lozano-Parra, J.; Maneta, M. P.; Schnabel, S.

2013-12-01

315

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

316

Gamma production and inferred level cross sections for inelastic neutron scattering from ^159Tb  

Microsoft Academic Search

Differential gamma-ray production cross sections for the ^159Tb (n,n'gamma) reaction were measured at 125^o for incident neutron energies in the 375- to 975-keV range. Neutron level cross sections were inferred from the measurements. Thin (50 keV) metallic lithium targets were used to generate neutrons via the ^7Li(p,n)^7Be reaction at the UML Van de Graaff accelerator. A Ge detector was used

P.-N. Seo; G. H. R. Kegel; J. J. Egan; D. J. Desimone; T. McKittrick; C. Ji; D. S. Kim; B. Tian; Y. J. Ko

1999-01-01

317

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

318

Chilling-enhanced photooxidation: The production, action and study of reactive oxygen species produced during chilling in the light  

Microsoft Academic Search

Chilling-enhanced photooxidation is the light- and oxygen-dependent bleaching of photosynthetic pigments that occurs upon the exposure of chilling-sensitive plants to temperatures below approximately 10 °C. The oxidants responsible for the bleaching are the reactive oxygen species (ROS) singlet oxygen (1O2), superoxide anion radical (O2?,hydrogen peroxide (H2O2), the hydroxyl radical (OH·), and the monodehydroascorbate radical (MDA) which are generated by a

Robert R. Wise

1995-01-01

319

Production of reactive single- and multi-component ceramic oxide powders and fabrication of high-strength ceramics  

Microsoft Academic Search

Yttria-partially stabilized zirconia (Y-PSZ), alumina, mullite, Y-PSZ-Al2O3, alumina-zirconia and mullite-zirconia precursor powders were prepared by the hydroxide precipitation technique. The experimental conditions during precipitation were manipulated to produce homogeneous and reactive powders and examples of such variations are discussed. The formation of chemically bonded hard agglomerates was suppressed by dispersing the powders in isopropanol. The powders could be sintered to

S. Rajendran

1992-01-01

320

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

321

Charged kaon production by coherent scattering of neutrinos and antineutrinos on nuclei  

NASA Astrophysics Data System (ADS)

With the aim of achieving a better and more complete understanding of neutrino interactions with nuclear targets, the coherent production of charged kaons induced by neutrinos and antineutrinos is investigated in the energy range of some of the current neutrino experiments. We follow a microscopic approach which, at the nucleon level, incorporates the most important mechanisms allowed by the chiral-symmetry-breaking pattern of QCD. The distortion of the outgoing K (K¯) is taken into account by solving the Klein-Gordon equation with realistic optical potentials. Angular and momentum distributions, as well as the energy and nuclear dependence of the total cross section, are studied.

Alvarez-Ruso, L.; Nieves, J.; Simo, I. Ruiz; Valverde, M.; Vacas, M. J. Vicente

2013-01-01

322

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

323

Enhancement by tumor necrosis factor alpha of dengue virus-induced endothelial cell production of reactive nitrogen and oxygen species is key to hemorrhage development.  

PubMed

Hemorrhage is a severe manifestation of dengue disease. Virus strain and host immune response have been implicated as the risk factors for hemorrhage development. To delineate the complex interplay between the virus and the host, we established a dengue hemorrhage model in immune-competent mice. Mice inoculated intradermally with dengue virus develop hemorrhage within 3 days. In the present study, we showed by the presence of NS1 antigen and viral nuclei acid that dengue virus actively infects the endothelium at 12 h and 24 h after inoculation. Temporal studies showed that beginning at day 2, there was macrophage infiltration into the vicinity of the endothelium, increased tumor necrosis factor alpha (TNF-alpha) production, and endothelial cell apoptosis in the tissues. In the meantime, endothelial cells in the hemorrhage tissues expressed inducible nitric oxide synthase (iNOS) and nitrotyrosine. In vitro studies showed that primary mouse and human endothelial cells were productively infected by dengue virus. Infection by dengue virus induced endothelial cell production of reactive nitrogen and oxygen species and apoptotic cell death, which was greatly enhanced by TNF-alpha. N(G)-nitro-L-arginine methyl ester and N-acetyl cysteine reversed the effects of dengue virus and TNF-alpha on endothelial cells. Importantly, hemorrhage development and the severity of hemorrhage were greatly reduced in mice lacking iNOS or p47(phox) or treatment with oxidase inhibitor, pointing to the critical roles of reactive nitrogen and oxygen species in dengue hemorrhage. PMID:18842737

Yen, Yu-Ting; Chen, Hsuen-Chin; Chen, Hseun-Chin; Lin, Yang-Ding; Shieh, Chi-Chang; Wu-Hsieh, Betty A

2008-12-01

324

Enhancement by Tumor Necrosis Factor Alpha of Dengue Virus-Induced Endothelial Cell Production of Reactive Nitrogen and Oxygen Species Is Key to Hemorrhage Development?  

PubMed Central

Hemorrhage is a severe manifestation of dengue disease. Virus strain and host immune response have been implicated as the risk factors for hemorrhage development. To delineate the complex interplay between the virus and the host, we established a dengue hemorrhage model in immune-competent mice. Mice inoculated intradermally with dengue virus develop hemorrhage within 3 days. In the present study, we showed by the presence of NS1 antigen and viral nuclei acid that dengue virus actively infects the endothelium at 12 h and 24 h after inoculation. Temporal studies showed that beginning at day 2, there was macrophage infiltration into the vicinity of the endothelium, increased tumor necrosis factor alpha (TNF-?) production, and endothelial cell apoptosis in the tissues. In the meantime, endothelial cells in the hemorrhage tissues expressed inducible nitric oxide synthase (iNOS) and nitrotyrosine. In vitro studies showed that primary mouse and human endothelial cells were productively infected by dengue virus. Infection by dengue virus induced endothelial cell production of reactive nitrogen and oxygen species and apoptotic cell death, which was greatly enhanced by TNF-?. NG-Nitro-l-arginine methyl ester and N-acetyl cysteine reversed the effects of dengue virus and TNF-? on endothelial cells. Importantly, hemorrhage development and the severity of hemorrhage were greatly reduced in mice lacking iNOS or p47phox or treatment with oxidase inhibitor, pointing to the critical roles of reactive nitrogen and oxygen species in dengue hemorrhage.

Yen, Yu-Ting; Chen, Hseun-Chin; Lin, Yang-Ding; Shieh, Chi-Chang; Wu-Hsieh, Betty A.

2008-01-01

325

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

326

Observation by flow sup 1 H NMR and dimerization kinetics and products of reactive ortho-quinodimethanes and benzocyclobutadiene  

SciTech Connect

The reactive o-quinodimethanes, 1,2-dimethylene-1,2-dihydronaphthalene (9) and o-xylylene (1) were observed by flow {sup 1}H NMR spectroscopy at room temperature. The {sup 1}H NMR spectrum of 9 was obtained in the absence of precursor and dimers. However, the {sup 1}H NMR spectrum of the more reactive 1, generated in a similar manner from (o-((trimethylsilyl)methyl)benzyl)trimethylammonium iodide (5.) could be obtained only in the presence of its stable (4 + 2) and (4 + 4) dimers. The dimerization kinetics of 3-methyl- (5{prime}), 3,6-dimethyl- (11), 3-isopropyl- (12), and 3,6-diisoproply-1,2-xylylene (13) in acetonitrile (CH{sub 3}CN) were studied by stopped-flow UV-visible spectroscopy. Fluoride ion induced 1,2-elimination from 2-elimination from 2-trimethylsilylbenzocyclobutenyl-1 mesylate (26) was used to generate the reactive molecule benzocyclobutadiene (1{prime}) in CD{sub 3}CN, which was observed by flow {sup 1}H NMR spectroscopy at room temperature. The {sup 1}H NMR spectrum (in CD{sub 3}CN) of 1,2-dimethylene-1,2-dihydrothiophene (1{double prime}), obtained by fluoride ion induced 1,4-elimination from 3-(trimethylammoniummethyl)-2-(trimethylsilylmethyl)thiophene iodine was observed by flow {sup 1}H NMR spectroscopy at room temperature. The dimerization rate of 1{double prime} in CH{sub 3}CN, generated in the same manner, was measured by UV-visible spectroscopy. 166 refs., 7 figs., 7 tabs.

Fischer, D.

1990-09-21

327

Production and characterization of Ti:sapphire thin films grown by reactive laser ablation with elemental precursors.  

PubMed

Crystalline Ti:sapphire (Ti:Al(2)O(3)) thin films were grown at low temperatures upon Al(2)O(3) (0001) substrates by reactive crossed-beam laser ablation at 248 nm by use of a liquid Ti-Al alloy target and O(2) . The films were investigated ex situ by x-ray diffraction, x-ray photoelectron spectroscopy, and Rutherford backscattering spectrometry. Low-temperature luminescence was identical to that for Ti(3+) ions in bulk samples of Al(2)O(3) . PMID:18079870

Willmott, P R; Manoravi, P; Huber, J R; Greber, T; Murray, T A; Holliday, K

1999-11-15

328

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

329

Oxidation of Fatty Acids Is the Source of Increased Mitochondrial Reactive Oxygen Species Production in Kidney Cortical Tubules in Early Diabetes  

PubMed Central

Mitochondrial reactive oxygen species (ROS) cause kidney damage in diabetes. We investigated the source and site of ROS production by kidney cortical tubule mitochondria in streptozotocin-induced type 1 diabetes in rats. In diabetic mitochondria, the increased amounts and activities of selective fatty acid oxidation enzymes is associated with increased oxidative phosphorylation and net ROS production with fatty acid substrates (by 40% and 30%, respectively), whereas pyruvate oxidation is decreased and pyruvate-supported ROS production is unchanged. Oxidation of substrates that donate electrons at specific sites in the electron transport chain (ETC) is unchanged. The increased maximal production of ROS with fatty acid oxidation is not affected by limiting the electron flow from complex I into complex III. The maximal capacity of the ubiquinol oxidation site in complex III in generating ROS does not differ between the control and diabetic mitochondria. In conclusion, the mitochondrial ETC is neither the target nor the site of ROS production in kidney tubule mitochondria in short-term diabetes. Mitochondrial fatty acid oxidation is the source of the increased net ROS production, and the site of electron leakage is located proximal to coenzyme Q at the electron transfer flavoprotein that shuttles electrons from acyl-CoA dehydrogenases to coenzyme Q.

Rosca, Mariana G.; Vazquez, Edwin J.; Chen, Qun; Kerner, Janos; Kern, Timothy S.; Hoppel, Charles L.

2012-01-01

330

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

331

Cross-reactivity of various thrombin products with anti-rabbit antibodies to bovine, human, and recombinant thrombin.  

PubMed

JMI-thrombin is used as topical hemostatic agent. While earlier clinically available JMI were reported to produce immunologic responses upon repeated exposure, the improved JMI, Recothrom?, and Evithrom? are claimed to be less immunogenic. Recothrom, despite its reduced immunogenic nature, upon repeated administration may result in the generation of antibodies (Abs) and that may cross react with bovine and human thrombin. Therefore, groups of rabbits were challenged repeatedly with Recothrom, Evithrom, and JMI over a 9-month period. Pre-immune blood and antiserum were collected from each rabbit on different time point. To determine their relative cross reactivity, JMI, Recothrom, and Evithrom were evaluated by western blotting using the rabbit IgG fractions. The results suggest that anti-Recothrom Abs cross-react with Evithrom and JMI in a time dependent fashion. Anti-JMI Abs did not cross-react with Recothrom, and Evithrom. Also, anti-Evithrom did not show any cross-reactivity with Recothrom and JMI at any time. PMID:22345489

Sadeghi, Nasir; Zhu, He; Setty, Saayi Krushna Gadham; Cunanan, Josephine; Hoppensteadt, Debra; Fareed, Jawed

2012-06-01

332

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

333

Arbitrary high-order C0 tensor product Galerkin finite element methods for the electromagnetic scattering from a large cavity  

NASA Astrophysics Data System (ADS)

The paper is concerned with the electromagnetic scattering from a large cavity embedded in an infinite ground plane. The electromagnetic cavity problem is described by the Helmholtz equation with a nonlocal boundary condition on the aperture of the cavity and Dirichlet (or Neumann) boundary conditions on the walls of the cavity. A tensor product Galerkin finite element method (FEM) is proposed, in which spaces of C0 piecewise polynomials of degree ??1 are employed. By the fast Fourier transform and the Toeplitz-type structure of the approximation to the nonlocal operator in the nonlocal boundary condition, a fast algorithm is designed for solving the linear system arising from the cavity problem with (vertically) layered media, which requires O(N2logN) operations on an N×N uniform partition. Numerical results for model problems illustrate the efficiency of the fast algorithm and exhibit the expected optimal global convergence rates of the finite element methods. Moreover, our numerical results also show that the high-order approximations are especially effective for problems with large wave numbers.

Du, Kui; Sun, Weiwei; Zhang, Xiaoping

2013-06-01

334

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

335

Optimization of culture medium composition for manganese peroxidase and tyrosinase production during Reactive Black 5 decolourization by the yeast Trichosporon akiyoshidainum.  

PubMed

Decolourization and degradation of the diazo dye Reactive Black 5 was carried out by the yeast Trichosporon akiyoshidainum. A nine-factor Plackett-Burman design was employed for the study and optimization of the decolourization process and production of manganese peroxidase (MnP) and tyrosinase activities. In the present study, 26 individual experiments were conducted and three responses were evaluated. Raising yeast extract concentration significantly enhanced decolourization and MnP production. Carbon and nitrogen sources, glucose and (NH4)2 SO4, showed no significant effect on any response over the concentration range tested. Other culture medium components, such as CaCl2 or MgSO4, could be excluded from the medium formula, as they had no effect on the evaluated responses. Metal ions (Fe, Cu and Mn) showed different effects on decolourization and enzymatic activities. Addition of copper significantly enhanced MnP activity and decreased dye decolourization. On the contrary, iron had a positive effect on decolourization and no effect on enzyme production. Oddly, increasing manganese concentration had a positive effect on tyrosinase production without affecting decolourization or MnP activity. These results strongly suggest that dye decolourization should be regarded as a complex multi-enzymatic process, where optimal medium composition should arise as a compromise between those optimal for each implied enzyme production. PMID:22447575

Martorell, María M; Pajot, Hipólito F; Rovati, José I; Figueroa, Lucía I C

2012-03-01

336

Parthenolide induces significant apoptosis and production of reactive oxygen species in high-risk pre-B leukemia cells.  

PubMed

We investigated whether parthenolide, the principal bioactive component of the herb feverfew (Tanacetum parthenium) induced apoptosis in pre-B acute lymphoblastic leukemia (ALL) lines, including cells carrying the t(4;11)(q21;q23) chromosomal translocation. Parthenolide induced rapid apoptotic cell death distinguished by loss of nuclear DNA, externalization of cell membrane phosphatidylserine, and depolarization of mitochondrial membranes at concentrations ranging from 5 to 100 microM. Using reactive oxygen species (ROS)-specific dyes, an increase in nitric oxide and superoxide anion was detected in the cells by 4 h after exposure to parthenolide. Parthenolide-induced elevation of hypochlorite anion was observed only in the two t(4;11) lines. These data suggest parthenolide may have potential as a potent and novel therapeutic agent against pre-B ALLs. PMID:17470383

Zunino, Susan J; Ducore, Jonathan M; Storms, David H

2007-08-28

337

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

2013-04-01

338

Physical vapour deposition reactive magnetron sputtering for the production and application of dichroics in photovoltaic system with solar spectral splitting  

NASA Astrophysics Data System (ADS)

This paper aims at designing, producing and characterizing a series of dichroic filters that are made up of a stack of layers with variable nanometer thickness. Such filters are created by PVD reactive magnetron sputtering, obtaining SiO2 and TiO2 through an active oxidation during the deposition. The single layers have then been analyzed using different techniques including RBS (Rutherford Backscattering Spectrometry) to determine the stoichiometry, AFM (Atomic Force Microscope) to assess the deposition rate, and UV-vis-NIR spectrophotometric analysis to evaluate the optical response. The application of the dichroic in concentration photovoltaic systems, separates the solar radiation in two optical spectral bands [7], that allows to couple them with a different solar cells which have dedicated external quantum efficiency. The optical separation using dichroic filters allows to combine different photovoltaic cells with an appropriate energy gap, thus optimizing the photovoltaic conversion.

Raniero, W.; Campostrini, M.; Maggioni, G.; Mea, G. Della; Quaranta, A.

2014-07-01

339

Transformation by retroviral vectors of bone marrow-derived mesenchymal cells induces mitochondria-dependent cAMP-sensitive reactive oxygen species production.  

PubMed

Retroviral vectors are used in human gene therapy trials to stably introduce therapeutic genes in the genome of patients' cells. Their applicability, however, is frustrated by the limited viability of transformed cells and/or by risks linked to selection of oncogene-mutated clones. The reasons for these drawbacks are not yet completely understood. In this study, we show that LXSN-NeoR gene/interleukin-7-engineered mesenchymal stromal cells exhibited a marked enhancement of reactive oxygen species production compared with untransfected cells. This effect resulted to be independent on the product of the gene carried by the retroviral vehicle as it was reproducible in cells transfected with the empty vector alone. Stable transfection of mesenchymal stromal cells with the different retroviral vectors pBabe-puro and PINCO-puro and the lentiviral vector pSico PGK-puro caused similar redox imbalance, unveiling a phenomenon of more general impact. The enhanced production of reactive oxygen species over the basal level was attributable to mitochondrial dysfunction and brought back to altered activity of the NADH-CoQ oxidoreductase (complex I) of the respiratory chain. The oxidative stress in transfected mesenchymal stem cells was completely reversed by treatment with a cAMP analog, thus pointing to alteration in the protein kinase A-dependent signaling pathway of the host cell. Transfection of mesenchymal stromal cells with a PINCO-parental vector harboring the green fluorescent protein gene as selection marker in place of the puromycin-resistance gene resulted in no alteration of the redox phenotype. These novel findings provide insights and caveats to the applicability of cell- or gene-based therapies and indicate possible intervention to improve them. Disclosure of potential conflicts of interest is found at the end of this article. PMID:18787213

Piccoli, Claudia; Scrima, Rosella; Ripoli, Maria; Di Ianni, Mauro; Del Papa, Beatrice; D'Aprile, Annamaria; Quarato, Giovanni; Martelli, Maria Paola; Servillo, Giuseppe; Ligas, Claudio; Boffoli, Domenico; Tabilio, Antonio; Capitanio, Nazzareno

2008-11-01

340

Pycnogenol® inhibits lipid accumulation in 3T3-L1 adipocytes with the modulation of reactive oxygen species (ROS) production associated with antioxidant enzyme responses.  

PubMed

Pycnogenol® is a group of flavonoids with antioxidant effects. Adipogenesis is the process of adipocyte differentiation. It causes the increase of lipids as well as ROS (reactive oxygen species). Lipid accumulation and ROS production were determined in 3?T3-L1 adipocyte, and the effect of Pycnogenol® was evaluated. Lipid accumulation was elevated in adipocyte treated with hydrogen peroxide, one of the ROS. Pycnogenol® showed an inhibitory effect on the lipid accumulation and ROS production during the adipogenesis. We also investigated the molecular events associated with ROS production and lipid accumulation. Our results showed that Pycnogenol® inhibited the mRNA expression of pro-oxidant enzymes, such as NOX4 (NADPH (nicotinamide adenine dinucleotide phosphate hydrogen) oxidase 4), and the NADPH-producing G6PDH (glucose-6-phosphate dehydrogenase) enzyme. In addition, Pycnogenol® suppressed the mRNA abundance of adipogenic transcription factors, PPAR-? (peroxisome proliferator-activated receptor ?) and C/EBP-? (CCAAT/enhancer binding protein ?), and their target gene, aP2 (adipocyte protein 2) responsible for fatty acid transportation. On the other hand, Pycnogenol® increased the abundance of antioxidant proteins such as Cu/Zn-SOD (copper-zinc superoxide dismutase), Mn-SOD (manganese superoxide dismutase), GPx (glutathione peroxidase) and GR (glutathione reductase). Our results suggest that Pycnogenol® inhibits lipid accumulation and ROS production by regulating adipogenic gene expression and pro-/antioxidant enzyme responses in adipocytes. PMID:21796705

Lee, Ok-Hwan; Seo, Min-Jung; Choi, Hyeon-Son; Lee, Boo-Yong

2012-03-01

341

IgG and IgA enhance the chrysotile-induced production of reactive oxygen metabolites by human polymorphonuclear leucocytes.  

PubMed Central

Chrysotile asbestos fibres induce a rapid generation of reactive oxygen metabolites by human polymorphonuclear leucocytes (PMNL) in vitro. This effect was markedly enhanced by the presence of 10-200 micrograms/ml of human gammaglobulin, purified polyclonal IgG, and monoclonal IgG and IgA myeloma proteins. Purified monoclonal IgD, IgM, kappa light chain proteins, and secretory IgA inhibited this chrysotile-induced response. No enhancing effect of IgG was observed when quartz dust or opsonized zymosan were used as stimulators of PMNL metabolism. The enhancing effect of IgG was shown to depend on opsonization of the asbestos fibre. We suggest that the IgG and IgA potentiating effect on the asbestos fibre-induced production of tissue-damaging reactive oxygen metabolites by inflammatory cells is dependent on a particle-specific binding of immunoglobulin to the fibre surface, with subsequent Fc receptor-mediated effects on cells. Such an interaction between certain immunoglobulins and asbestos may explain a number of in vivo phenomena in which immunological responses (hypergammaglobulinemia, circulating immune complexes, etc.) have been shown to relate to the progression of pulmonary asbestosis. The differences between various immunoglobulin classes and monoclonal immunoglobulins could represent an individual inflammation-modulating mechanism in the development of acute or chronic pulmonary asbestosis.

Klockars, M; Hedenborg, M; Koistinen, J; Isobe, T

1989-01-01

342

Production of reactive oxygen and nitrogen species by light irradiation of a nitrosyl phthalocyanine ruthenium complex as a strategy for cancer treatment.  

PubMed

Production of reactive oxygen species has been used in clinical therapy for cancer treatment in a technique known as Photodynamic Therapy (PDT). The success of this therapy depends on oxygen concentration since hypoxia limits the formation of reactive oxygen species with consequent clinical failure of PDT. Herein, a possible synergistic effect between singlet oxygen and nitric oxide (NO) is examined since this scenario may display increased tumoricidal activity. To this end, the trinuclear species [Ru(pc)(pz)2{Ru(bpy)2(NO)}2](PF6)6 (pc = phthalocyanine; pz = pyrazine; bpy = bipyridine) was synthesized to be a combined NO and singlet oxygen photogenerator. Photobiological assays using at 4 × 10(-6) M in the B16F10 cell line result in the decrease of cell viability to 21.78 ± 0.29% of normal under light irradiation at 660 nm. However, in the dark and at the same concentration of compound , viability was 91.82 ± 0.37% of normal. The potential application of a system like in clinical therapy against cancer may be as an upgrade to normal photodynamic therapy. PMID:24452093

Heinrich, Tassiele A; Tedesco, Antonio Claudio; Fukuto, Jon M; da Silva, Roberto Santana

2014-03-14

343

Working Memory and Reactivity  

ERIC Educational Resources Information Center

The present study explores the relationship between working memory capacity (WMC) and think-alouds, focusing on the issue of reactivity. Two WM span tasks (listening span and operation span) were administered to 42 English-speaking learners of Spanish. Learner performance on reading comprehension and written production was measured under two…

Goo, Jaemyung

2010-01-01

344

Reactive scattering in the ultracold regime  

NASA Astrophysics Data System (ADS)

We calculate reaction cross sections for D + H2 in the ultracold regime, using the abc program developed by Manolopoulos and his collaborators.(D. Skouteris, J. F. Castillo, D. E. Manolopoulos, Comput. Phys. Commun. 133), 128 (2000). As expected, the results we obtain are in agreement with Wigner's threshold law. For H_2(v=1), the total reaction cross section is smaller than the total quenching cross section, but for v>= 2 the situation is reversed. We analyze in detail the rovibrational distributions for several initial vibrational states of H_2. Preliminary results for Cl + H2 are also presented.

Simbotin, I.; Côté, R.; Balakrishnan, N.; Dalgarno, A.

2002-05-01

345

Formation of ferrihydrite and associated iron corrosion products in permeable reactive barriers of zero-valent iron  

NASA Technical Reports Server (NTRS)

Ferrihydrite, which is known to form in the presence of oxygen and to be stabilized by the adsorption of Si, PO4 and SO4, is ubiquitous in the fine-grained fractions of permeable reactive barrier (PRB) samples from the U.S. Coast Guard Support Center (Elizabeth City, NC) and the Denver Federal Center (Lakewood, CO) studied by high-resolution transmission electron microscopy and selected area electron diffraction. The concurrent energy-dispersive X-ray data indicate a strong association between ferrihydrite and metals such as Si, Ca, and Cr. Magnetite, green rust 1, aragonite, calcite, mackinawite, greigite and lepidocrocite were also present, indicative of a geochemical environment that is temporally and spatially heterogeneous. Whereas magnetite, which is known to form due to anaerobic Fe0 corrosion, passivates the Fe0 surface, ferrihydrite precipitation occurs away from the immediate Fe0 surface, forming small (<0.1 microm) discrete clusters. Consequently, Fe0-PRBs may remain effective for a longer period of time in slightly oxidized groundwater systems where ferrihydrite formation occurs compared to oxygen-depleted systems where magnetite passivation occurs. The ubiquitous presence of ferrihydrite suggests that the use of Fe0-PRBs may be extended to applications that require contaminant adsorption rather than, or in addition to, redox-promoted contaminant degradation.

Furukawa, Yoko; Kim, Jin-Wook; Watkins, Janet; Wilkin, Richard T.

2002-01-01

346

Induction of apoptosis by Meretrix lusoria through reactive oxygen species production, glutathione depletion, and caspase activation in human leukemia cells.  

PubMed

Apoptosis-induced directed fractionation and purification was used to identify the bioactive components of hard clams (HC), Meretrix lusoria. Two stereoisomers of epidioxysterol were previously identified as the active compounds in the ethyl acetate fraction (HC-EA). The molecular mechanism of HC-EA-induced apoptosis was also investigated in this study. Dissipation of mitochondrial membrane potential, release of mitochondrial cytochrome c into cytosol, and subsequent induction of pro-caspase-9 and -3 processing preceded apoptosis in HL-60 cells, confirmed by DNA fragmentation, chromatin condensation, changes in the cell membrane and the appearance of a sub-G1 DNA peak. Furthermore, treatment with HC-EA caused a rapid loss of intracellular glutathione content and stimulation of reactive oxygen species (ROS). Antioxidants such as catalase, N-acetylcysteine, pyrrolidine dithiocarbamate, and superoxide dismutase, but not allopurinol and diphenylene iodonium, significantly inhibited HC-EA-induced cell death. Apoptosis was completely prevented by a pan-caspase inhibitor, z-Val-Ala-Asp-fluoromethyl ketone (z-VAD-FMK). The induction of apoptosis by M. lusoria may prove to be a pivotal mechanism for its cancer chemopreventive action. PMID:16730358

Pan, Min-Hsiung; Huang, Yu-Ting; Ho, Chi-Tang; Chang, Chi-I; Hsu, Ping-Chi; Sun Pan, Bonnie

2006-08-15

347

Honokiol induces caspase-independent paraptosis via reactive oxygen species production that is accompanied by apoptosis in leukemia cells.  

PubMed

Our previous report has shown that honokiol (HNK), a constituent of Magnolia officinalis, induces a novel form of non-apoptotic programmed cell death in human leukemia NB4 and K562 cells. In this study, we further explored the relationship between the cell death pathway and cytoplasmic vacuolization and studied the underlying mechanism of leukemia cell death mediated by honokiol. The results showed that low concentrations of honokiol activated an novel alternative cell death fitted the criteria of paraptosis, such as cytoplasmic vacuolization derived from endoplasmic reticulum swelling, lack of caspase activation, and lack of apoptotic morphology. Results further indicated that the cell death was time- and concentration-dependent. In addition, honokiol-induced paraptosis did not involve membrane blebbing, chromatin condensation and phosphatidylserine exposure at the outer of the plasma membrane. The mechanism of the cell death may be associated, at least in part, with the increased generation of reactive oxygen species. Further analysis showed that honokiol induces cell death predominantly via paraptosis and to a certain extent via apoptosis in NB4 cells, and predominantly via apoptosis and to a certain extent via paraptosis in K562 cells. These observations suggest that cell death occurs via more than one pathway in leukemia cells and targeting paraptosis may be an alternative and promising avenue for honokiol in leukemia therapy. PMID:23262230

Wang, Yao; Zhu, Xiuping; Yang, Zehong; Zhao, Xiaojun

2013-01-18

348

Transient Influx of Nickel in Root Mitochondria Modulates Organic Acid and Reactive Oxygen Species Production in Nickel Hyperaccumulator Alyssum murale*  

PubMed Central

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.

Agrawal, Bhavana; Czymmek, Kirk J.; Sparks, Donald L.; Bais, Harsh P.

2013-01-01

349

Reactive quenching of OH A 2?+ by O2 and CO: Experimental and nonadiabatic theoretical studies of H- and O-atom product channels  

NASA Astrophysics Data System (ADS)

The outcomes following collisional quenching of electronically excited OH A 2?+ by O2 and CO are examined in a combined experimental and theoretical study. The atomic products from reactive quenching are probed using two-photon laser-induced fluorescence to obtain H-atom Doppler profiles, O (3PJ) atom fine structure distributions, and the relative yields of these products with H2, O2, and CO collision partners. The corresponding H-atom translational energy distributions are extracted for the H + O3 and H + CO2 product channels, in the latter case revealing that most of the available energy is funneled into internal excitation of CO2. The experimental product branching ratios show that the O-atom producing pathways are the dominant outcomes of quenching: the OH A 2?+ + O2 --> O + HO2 channel accounts for 48(3)% of products and the OH A 2?+ + CO --> O + HCO channel yields 76(5)% of products. In addition, quenching of OH A 2?+ by O2 generates H + O3 products [12(3)%] and returns OH to its ground X 2? electronic state [40(1)% L. P. Dempsey, T. D. Sechler, C. Murray, and M. I. Lester, J. Phys. Chem. A 113, 6851 (2009)]. Quenching of OH A 2?+ by CO also yields H + CO2 reaction products [26(5)%] however, OH X 2? (v'' = 0,1) products from nonreactive quenching are not observed. Theoretical studies characterize the properties of energy minimized conical intersections in four regions of strong nonadiabatic coupling accessible from the OH A 2?+ + CO asymptote. Three of these regions have the O-side of OH pointing toward CO, which lead to atomic H and vibrationally excited CO2 products and/or nonreactive quenching. In the fourth region, energy minimized points are located on a seam of conical intersection from the OH A 2?+ + CO asymptote to an energy minimized crossing with an extended OH bond length and the H-side of OH pointing toward CO in a bent configuration. This region, exoergic with respect to the reaction asymptote, is likely to be the origin of the dominant O + HCO product channel.

Lehman, Julia H.; Lester, Marsha I.; Yarkony, David R.

2012-09-01

350

Hydrogen-rich water inhibits glucose and ?,? -dicarbonyl compound-induced reactive oxygen species production in the SHR.Cg-Leprcp/NDmcr rat kidney  

PubMed Central

Background Reactive oxygen species (ROS) production induced by ?,?-dicarbonyl compounds and advanced glycation end products causes renal dysfunction in patients with type 2 diabetes and metabolic syndrome. Hydrogen-rich water (HRW) increases the H2 level in blood and tissues, thus reducing oxidative stress in animals as well as humans. In this study, we investigated the effects of HRW on glucose- and ?,?-dicarbonyl compou