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1.
  • Adcox, K, et al. (author)
  • PHENIX detector overview
  • 2003
  • In: Nuclear Instruments & Methods in Physics Research. Section A: Accelerators, Spectrometers, Detectors, and Associated Equipment. - 0167-5087. ; 499:2-3, s. 469-479
  • Journal article (peer-reviewed)abstract
    • The PHENIX detector is designed to perform a broad study of A-A, p-A, and p-p collisions to investigate nuclear matter under extreme conditions. A wide variety of probes, sensitive to all timescales, are used to study systematic variations with species and energy as well as to measure the spin structure of the nucleon. Designing for the needs of the heavy-ion and polarized-proton programs has produced a detector with unparalleled capabilities. PHENIX measures electron and muon pairs, photons, and hadrons with excellent energy and momentum resolution. The detector consists of a large number of subsystems that are discussed in other papers in this volume. The overall design parameters of the detector are presented. (C) 2002 Elsevier Science B.V. All rights reserved.
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2.
  • Adler, SS, et al. (author)
  • Scaling properties of proton and antiproton production in root s(NN)=200 GeV Au+Au collisions
  • 2003
  • In: Physical Review Letters. - 1079-7114. ; 91:17: 172301
  • Journal article (peer-reviewed)abstract
    • We report on the yield of protons and antiprotons, as a function of centrality and transverse momentum, in Au+Au collisions at rootS(NN)=200 GeV measured at midrapidity by the PHENIX experiment at the BNL Relativistic Heavy Ion Collider. In central collisions at intermediate transverse momenta (1.5
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3.
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4.
  • Adcox, K, et al. (author)
  • Flow Measurements via Two-Particle Azimuthal Correlations in Au+Au Collisions at sqrt[sNN]=130 GeV
  • 2002
  • In: Physical Review Letters. - 1079-7114. ; 89
  • Journal article (peer-reviewed)abstract
    • Two-particle azimuthal correlation functions are presented for charged hadrons produced in Au+Au collisions at the Relativistic Heavy Ion Collider (sqrt[sNN]=130 GeV). The measurements permit determination of elliptic flow without event-by-event estimation of the reaction plane. The extracted elliptic flow values (v2) show significant sensitivity to both the collision centrality and the transverse momenta of emitted hadrons, suggesting rapid thermalization and relatively strong velocity fields. When scaled by the eccentricity of the collision zone ε, the scaled elliptic flow shows little or no dependence on centrality for charged hadrons with relatively low pT. A breakdown of this ε scaling is observed for charged hadrons with pT >1.0 GeV/c.
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5.
  • Adler, SS, et al. (author)
  • Bose-Einstein correlations of charged pion pairs in Au+Au collisions at root(NN)-N-s = 200 GeV
  • 2004
  • In: Physical Review Letters. - 1079-7114. ; 93:15
  • Journal article (peer-reviewed)abstract
    • Bose-Einstein correlations of identically charged pion pairs were measured by the PHENIX experiment at midrapidity in Au+Au collisions at roots(NN)=200 GeV. The Bertsch-Pratt radius parameters were determined as a function of the transverse momentum of the pair and as a function of the centrality of the collision. Using the standard core-halo partial Coulomb fits, and a new parametrization which constrains the Coulomb fraction as determined from the unlike-sign pion correlation, the ratio R-out/R-side is within 0.8-1.1 for 0.25<<1.2 GeV/c. The centrality dependence of all radii is well described by a linear scaling in N-part(1/3), and R-out/R-side for similar to0.45 GeV/c is approximately constant at unity as a function of centrality.
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6.
  • Adler, SS, et al. (author)
  • Elliptic flow of identified hadrons in Au+Au collisions at root s(NN)=200 GeV
  • 2003
  • In: Physical Review Letters. - 1079-7114. ; 91:18: 182301
  • Journal article (peer-reviewed)abstract
    • The anisotropy parameter (v(2)), the second harmonic of the azimuthal particle distribution, has been measured with the PHENIX detector in Au+Au collisions at roots(NN)=200 GeV for identified and inclusive charged particle production at central rapidities (eta<0.35) with respect to the reaction plane defined at high rapidities (eta=3-4 ). We observe that the v(2) of mesons falls below that of (anti)baryons for p(T)>2 GeV/c, in marked contrast to the predictions of a hydrodynamical model. A quark-coalescence model is also investigated.
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7.
  • Adler, SS, et al. (author)
  • J/psi production from proton-proton collisions at root s=200 GeV
  • 2004
  • In: Physical Review Letters. - 1079-7114. ; 92:5
  • Journal article (peer-reviewed)abstract
    • J/psi production has been measured in proton-proton collisions at roots=200 GeV over a wide rapidity and transverse momentum range by the PHENIX experiment at the Relativistic Heavy Ion Collider. Distributions of the rapidity and transverse momentum, along with measurements of the mean transverse momentum and total production cross section are presented and compared to available theoretical calculations. The total J/psi cross section is 4.0+/-0.6(stat)+/-0.6(syst)+/-0.4(abs) mub. The mean transverse momentum is 1.80+/-0.23(stat)+/-0.16(syst) GeV/c.
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8.
  • Adler, SS, et al. (author)
  • J/psi production in Au-Au collisions at root s(NN)=200 GeV
  • 2004
  • In: Physical Review C (Nuclear Physics). - 0556-2813. ; 69:1
  • Journal article (peer-reviewed)abstract
    • First results on charm quarkonia production in heavy ion collisions at the Relativistic Heavy Ion Collider (RHIC) are presented. The yield of J/psi's measured in the PHENIX experiment via electron-positron decay pairs at midrapidity for Au-Au reactions at roots(NN) = 200 GeV is analyzed as a function of collision centrality. For this analysis we have studied 49.3x10(6) minimum bias Au-Au reactions. We present the J/psi invariant yield dN/dy for peripheral and midcentral reactions. For the most central collisions where we observe no signal above background, we quote 90% confidence level upper limits. We compare these results with our J/psi measurement from proton-proton reactions at the same energy. We find that our measurements are not consistent with models that predict strong enhancement relative to binary collision scaling.
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9.
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10.
  • Adcox, K, et al. (author)
  • Centrality dependence of the high (PT) charged hadron suppression in Au+Au collisions at root s(NN)=130 GeV
  • 2003
  • In: Physics Letters. Section B: Nuclear, Elementary Particle and High-Energy Physics. - 0370-2693. ; 561:1-2, s. 82-92
  • Journal article (peer-reviewed)abstract
    • PHENIX has measured the centrality dependence of charged hadron p(T) spectra from Au +An collisions at root(s)NN = 130 GeV The truncated mean p(T) decreases with centrality for p(T) > 2 GeV/c, indicating an apparent reduction of the contribution from hard scattering to high p(T) hadrdn production. For central collisions the yield at high p(T) is shown to be suppressed compared to binary nucleon-nucleon collision scaling of p + p, data. This suppression is monotonically increasing with centrality, but most of the change occurs below 30% centrality, i.e., for collisions with less than similar to140 participating nucleons. The observed p(T) and centrality dependence is consistent with the particle production predicted by models including hard scattering and subsequent energy loss of the scattered partons in the dense matter created in the collisions. (C) 2003 Published by Elsevier Science B.V.
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11.
  • Adcox, K, et al. (author)
  • Event-by-event fluctuations in mean p(T) and mean E(T) in root s(NN)=130 GeVAu+Au collisions
  • 2002
  • In: Physical Review C (Nuclear Physics). - 0556-2813. ; 66:2
  • Journal article (peer-reviewed)abstract
    • Distributions of event-by-event fluctuations of the mean transverse momentum and mean transverse energy near mid-rapidity have been measured in Au+Au collisions at roots(NN)=130 GeV at the Relativistic Heavy-Ion Collider. By comparing the distributions to what is expected for statistically independent particle emission, the magnitude of nonstatistical fluctuations in mean transverse momentum is determined to be consistent with zero. Also, no significant nonrandom fluctuations in mean transverse energy are observed. By constructing a fluctuation model with two event classes that preserve the mean and variance of the semi-inclusive p(T) or e(T) spectra, we exclude a region of fluctuations in roots(NN)=130 GeV Au+Au collisions.
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12.
  • Adcox, K, et al. (author)
  • Measurement of Lambda and (Lambda)over-bar particles in Au plus Au collisions at root s(NN)=130 GeV
  • 2002
  • In: Physical Review Letters. - 1079-7114. ; 89:9
  • Journal article (peer-reviewed)abstract
    • We present results on the measurement of Lambda and (&ULambda;) over bar production in Au+Au collisions at roots(NN)=130 GeV with the PHENIX detector at the Relativistic Heavy Ion Collider. The transverse momentum spectra were measured for minimum bias and for the 5% most central events. The (&ULambda;) over bar/Lambda ratios are constant as a function of p(T) and the number of participants. The measured net Lambda density is significantly larger than predicted by models based on hadronic strings (e.g., HIJING) but in approximate agreement with models which include the gluon-junction mechanism.
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13.
  • Adcox, K, et al. (author)
  • Measurement of single electrons and implications for charm production in Au+Au collisions at root(NN)-N-S=130 GeV
  • 2002
  • In: Physical Review Letters. - 1079-7114. ; 88:19
  • Journal article (peer-reviewed)abstract
    • Transverse momentum spectra of electrons from Au+Au collisions at roots(NN) = 130 GeV have been measured at midrapidity by the PHENIX experiment at the Relativistic Heavy Ion Collider. The spectra show an excess above the background from photon conversions and light hadron decays. The electron signal is consistent with that expected from semileptonic decays of charm. The yield of the electron signal dN(e)/dy for p(T) > 0.8 GeV/c is 0.025 +/- 0.004(stat) +/- 0.010( syst) in central collisions, and the corresponding charm cross section is 380 +/- 60(stat) +/- 200(syst ) mub per binary nucleon-nucleon collision.
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14.
  • Adcox, K, et al. (author)
  • Net charge fluctuations in Au+Au interactions root s(NN)=130 GeV
  • 2002
  • In: Physical Review Letters. - 1079-7114. ; 89
  • Journal article (peer-reviewed)abstract
    • Data from Au+ Au interactions at s(NN)=130 GeV, obtained with the PHENIX detector at the Relativistic Heavy-Ion Collider, are used to investigate local net charge fluctuations among particles produced near midrapidity. According to recent suggestions, such fluctuations may carry information from the quark-gluon plasma. This analysis shows that the fluctuations are dominated by a stochastic distribution of particles, but are also sensitive to other effects, like global charge conservation and resonance decays.
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15.
  • Adcox, K, et al. (author)
  • Suppression of hadrons with large transverse momentum in central Au+Au collisions at root s(NN)=130 GeV
  • 2002
  • In: Physical Review Letters. - 1079-7114. ; 88:2
  • Journal article (peer-reviewed)abstract
    • Transverse momentum spectra for charged hadrons and for neutral pions in the range 1 Gev/c < P-T < 5 GeV/c have been measured by the PHENIX experiment at RHIC in Au + Au collisions at rootS(NN) = 130 GeV. At high p(T) the spectra from peripheral nuclear collisions are consistent with scaling the spectra from p + p collisions by the average number of binary nucleon-nucleon collisions. The spectra from central collisions are significantly suppressed when compared to the binary-scaled p + p expectation, and also when compared to similarly binary-scaled peripheral collisions, indicating a novel nuclear-medium effect in central nuclear collisions at RHIC energies.
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16.
  • Adcox, K, et al. (author)
  • Transverse-mass dependence of two-pion correlations in Au+Au collisions at root(NN)-N-S=130 GeV
  • 2002
  • In: Physical Review Letters. - 1079-7114. ; 88:19
  • Journal article (peer-reviewed)abstract
    • Two-pion correlations in roots(NN) = 130 GeV Au+Au collisions at RHIC have been measured over a broad range of pair transverse momentum k(T) by the PHENIX experiment at RHIC. The k(T) dependent transverse radii are similar to results from heavy-ion collisions at roots(NN) = 4.1 , 4.9, and 17.3 GeV, whereas the longitudinal radius increases monotonically with beam energy. The ratio of the outwards to sidewards transverse radii (R-out/R-side) is consistent with unity and independent of k(T) .
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17.
  • Adler, SS, et al. (author)
  • Double helicity asymmetry in inclusive midrapidity pi(0) production for polarized p+p collisions at root s=200 GeV
  • 2004
  • In: Physical Review Letters. - 1079-7114. ; 93:20: 202002
  • Journal article (peer-reviewed)abstract
    • We present a measurement of the double longitudinal spin asymmetry in inclusive pi(0) production in polarized proton-proton collisions at roots=200 GeV. The data were taken at the Relativistic Heavy Ion Collider with average beam polarizations of 0.27. The measurements are the first in a program to study the longitudinal spin structure of the proton, using strongly interacting probes, at collider energies. The asymmetry is presented for transverse momenta 1-5 GeV/c at midrapidity, where next-to-leading-order perturbative quantum chromodynamic (NLO pQCD) calculations well describe the unpolarized cross section. The observed asymmetry is small and is compared to a NLO pQCD calculation with a range of polarized gluon distributions.
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18.
  • Adler, SS, et al. (author)
  • PHENIX on-line systems
  • 2003
  • In: Nuclear Instruments & Methods in Physics Research. Section A: Accelerators, Spectrometers, Detectors, and Associated Equipment. - 0167-5087. ; 499:2-3, s. 560-592
  • Journal article (peer-reviewed)abstract
    • The PHENIX On-Line system takes signals from the Front End Modules (FEM) on each detector subsystem for the purpose of generating events for physics analysis. Processing of event data begins when the Data Collection Modules (DCM) receive data via fiber-optic links from the FEMs. The DCMs format and zero suppress the data and generate data packets. These packets go to the Event Builders (EvB) that assemble the events in final form. The Level-1 trigger (LVL1) generates a decision for each beam crossing and eliminates uninteresting events. The FEMs carry out all detector processing of the data so that it is delivered to the DCMs using a standard format. The FEMs also provide buffering for LVL1 trigger processing and DCM data collection. This is carried out using an architecture that is pipelined and deadtimeless. All of this is controlled by the Master Timing System (MTS) that distributes the RHIC clocks. A Level-2 trigger (LVL2) gives additional discrimination. A description of the components and operation of the PHENIX On-Line system is given and the solution to a number of electronic infrastructure problems are discussed. (C) 2002 Elsevier Science B.V. All rights reserved.
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19.
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20.
  • Zhang, Shi-Li, et al. (author)
  • Abnormal anti-Stokes Raman scattering of carbon nanotubes
  • 2002
  • In: Physical Review B. Condensed Matter and Materials Physics. - 1098-0121 .- 1550-235X. ; 66:3
  • Journal article (peer-reviewed)abstract
    • Abnormal anti-Stokes Raman scattering (AASR) was unambiguously observed in carbon nanotubes (CNT's). In contrast to traditional Raman scattering theory, the absolute value of the Raman frequency of the anti-Stokes peak is not the same as that of the corresponding Stokes peak. It was demonstrated that AASR scattering originates from the unique nanoscale cylindrical structure of CNT's that can be considered naturally as a graphite structure with an intrinsic defect from its rolling. The double-resonance Raman scattering theory was applied to interpret the scattering mechanism of the AASR phenomenon successfully and quantitatively.
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21.
  • Carlsson, Lena, et al. (author)
  • Differences in the distribution of synemin, paranemin, and plectin in skeletal muscles of wild-type and desmin knock-out mice
  • 2000
  • In: Histochemistry and Cell Biology. - : Springer. - 0948-6143 .- 1432-119X. ; 114:1, s. 39-47
  • Journal article (peer-reviewed)abstract
    • Mice lacking the gene encoding for the intermediate filament protein desmin have a surprisingly normal myofibrillar organization in skeletal muscle fibers, although myopathy develops in highly used muscles. In the present study we examined how synemin, paranemin, and plectin, three key cytoskeletal proteins related to desmin, are organized in normal and desmin knock-out (K/O) mice. We show that in wild-type mice, synemin, paranemin, and plectin were colocalized with desmin in Z-disc-associated striations and at the sarcolemma. All three proteins were also present at the myotendinous junctions and in the postsynaptic area of motor endplates. In the desmin K/O mice the distribution of plectin was unaffected, whereas synemin and paranemin were partly affected. The Z-disc-associated striations were in general no longer present in between the myofibrils. In contrast, at the myotendinous and neuromuscular junctions synemin and paranemin were still present. Our study shows that plectin differs from synemin and paranemin in its binding properties to the myofibrillar Z-discs and that the cytoskeleton in junctional areas is particularly complex in its organization.
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22.
  • Graham, J, et al. (author)
  • Genetic effects on age-dependent onset and islet cell autoantibody markers in type 1 diabetes
  • 2002
  • In: Diabetes. - : American Diabetes Association. - 0012-1797 .- 1939-327X. ; 51:5, s. 1346-1355
  • Journal article (peer-reviewed)abstract
    • Age-dependent associations between type 1 diabetes risk genes HLA, INS VNTR, and CTLA-4 and autoantibodies to GAD65 (GADAs), ICA512/IA-2, insulin, and islet cells were determined by logistic regression analysis in 971 incident patients with type 1 diabetes and 702 control subjects aged 0–34 years. GADAs were associated with HLA-DQ2 in young but not in older patients (P = 0.009). Autoantibodies to insulin were negatively associated with age (P &lt; 0.0001) but positively associated with DQ8 (P = 0.03) and with INS VNTR (P = 0.04), supporting possible immune tolerance induction. ICA512/IA-2 were negatively associated with age (P &lt; 0.0001) and with DQ2 (P &lt; 0.0001) but positively associated with DQ8 (P = 0.04). Males were more likely than females to be negative for GADA (P &lt; 0.0001), autoantibodies to islet cells (P = 0.04), and all four autoantibody markers (P = 0.004). The CTLA-4 3′ end microsatellite marker was not associated with any of the autoantibodies. We conclude that age and genetic factors such as HLA-DQ and INS VNTR need to be combined with islet autoantibody markers when evaluating the risk for type 1 diabetes development.
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23.
  • Hilden, L., et al. (author)
  • Do the extracellular enzymes cellobiose dehydrogenase and manganese peroxidase form a pathway in lignin biodegradation?
  • 2000
  • In: FEBS Letters. - 0014-5793 .- 1873-3468. ; 477:02-jan, s. 79-83
  • Journal article (peer-reviewed)abstract
    • The extracellular enzyme manganese peroxidase is believed to degrade lignin by a hydrogen peroxide-dependent oxidation of Mn(II) to the reactive species Mn(III) that attacks the lignin, However, Mn(III) is not able to directly oxidise the non-phenolic lignin structures that predominate in native lignin, We show here that pretreatment of a non-phenolic lignin model compound with another extracellular fungal enzyme, cellobiose dehydrogenase, allows the manganese peroxidase system to oxidise this molecule. The mechanism behind this effect is demethoxylation and/or hydroxylation, i.e. conversion of a nonphenolic structure to a phenolic one, mediated by hydroxyl radicals generated by cellobiose dehydrogenase, This suggests that cellobiose dehydrogenase and manganese peroxidase may act in an extracellular pathway in fungal lignin biodegradation, Analytical techniques used in this paper are reverse-phase high-pressure liquid chromatography, gas chromatography connected to mass spectroscopy and UV-visible spectroscopy.
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24.
  • Huang, D. G., et al. (author)
  • Synthesis, structural characterizations and magnetic properties of a series of mono-, di- and polynuclear manganese pyridinecarboxylate compounds
  • 2004
  • In: European Journal of Inorganic Chemistry. - : Wiley. - 1434-1948 .- 1099-1948 .- 1099-0682. ; :7, s. 1454-1464
  • Journal article (peer-reviewed)abstract
    • Seven new manganese(II, III, IV) pyridinecarboxylate compounds (Et4N)[MnCl2(pic)(2)] (1, Hpic = picolinic acid) [MnCl(Pic)(2)(H2O)].H2O (2), [MnCl(pic)(H2O)2](n) (3), [Mn(Pic)(2)](n) (4), [MnCl(pic)](n) (5), [MnCl2(4-C5H4NHCOO)](n) (6) and [Mn2O2(pic)(4)] (7) were synthesized and structurally characterized. The picolinate ligand coordinates to the Mn ion forming a chelating five-membered ring which constructs diverse architectures by various bridging modes, such as mu-Cl, mu(1,1)(-) and mu(1,3)-carboxylate bridges (syn-syn and syn-anti modes). The interaction between the pyridyl rings is discussed, displaying a face-to-face pi-pi stacking for complex 6 and a T-shaped C-H...pi attraction for complex 4. Complex 3 has an infinite zigzag chain structure in which two neighboring Mn ions are linked by a carboxylate bridge in a syn-anti mode. In complex 4, the Mn(pic)(2) fragments are joined to each other by double mu(1,1)-carboxylate bridges, forming a 2D layer structure. Complex 5 contains Mn4O4 square subunits which are connected by double mu-Cl bridges to form a grid-like 2D structure. The isonicotinate complex 6 has a zigzag chain structure containing mixed double mu-Cl and mu(1,3)-carboxylate bridges in a syn-syn mode. Protonation at the pyridyl-N position was found and identified by the IR and magnetic properties of 6. The participation of an oxidizing agent like MnO4- leads to complexes containing higher valent manganese (1, 2 and 7). The IR spectra of these complexes are discussed and found to be consistent with the structural features. The magnetic properties of complexes 4, 5 and 6 have been investigated. Antiferromagnetic coupling interactions were observed and satisfactory fitting results were obtained with J values ranging from -0.63 cm(-1) to -2.35 cm(-1). The magnetic parameters of these complexes, together with the parameters of other Mn complexes with comparable structures, are compared and discussed based on the bridging modes. ((C) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004).
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27.
  • Brookes, N. B., et al. (author)
  • Detection of Zhang-Rice singlets using spin-polarized photoemission
  • 2001
  • In: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 8723:23
  • Journal article (peer-reviewed)abstract
    • From a spin-resolved photoemission study on the Bi2Sr2CaCu2O8+delta superconductor, we show experimentally that the first ionization state is of nearly pure singlet character. This is true both above and below the superconducting transition and in the presence of doping and band formation. This provides direct support for the existence and stability of Zhang-Rice singlets in high-temperature superconductors, justifying the ansatz of single-band models. Moreover, we establish this technique as an important probe for a wide range of cuprates and strongly correlated materials.
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28.
  • Chen, C. N., et al. (author)
  • Aggregate manganese Schiff base moieties by terephthalate or acetate : Dinuclear manganese and trinuclear mixed metal Mn-2/Na complexes
  • 2003
  • In: Inorganic Chemistry. - : American Chemical Society (ACS). - 0020-1669 .- 1520-510X. ; 42:11, s. 3540-3548
  • Journal article (peer-reviewed)abstract
    • A reaction system consisting of terephthalic acid, NaOH, inorganic Mn(II) or Mn(III) salt, and salicylidene alkylimine resulted in dinuclear manganese complexes (salpn)(2)Mn-2(mu-phth)(CH3OH)(2) (1, salpn = N,N'-1,3-propylene-bis(salicylideneiminato); phth = terephthalate dianion), (salen)(2)Mn-2(mu-phth)(CH3OH)(2) (2, salen = N,N'-ethylene-bis(salicylideneiminato)), (salen)(2)Mn-2(mu-phth)(CH3OH)(H2O) (3), and (salen)(2)Mn-2(mu-phth) (4), while the absence of NaOH in the reaction led to a mononuclear Mn complex (salph)Mn(CH3OH)(NO3) (5, salph = N,N'-1,2-phenylene-bis(salicylideneiminato)). In addition, a trinuclear mixed metal complex H{Mn2Na(salpn)(2)(mu-OAc)(2)(H2O)(2)}(OAc)(2) (6) was obtained from the reaction system by using maleic acid instead of terephthalic acid. Five-coordinate Mn ions were found in 4 giving rise to an intermolecular interaction and constructing a one-dimensional linear structure. Antiferromagnetic exchange interactions were observed for 1-3, and a total ferromagnetic exchange of 4 was considered to stem from intermolecular magnetic coupling. H-1 NMR signals of phenolate ring and alkylene (or phenylene) backbone of the diamine are similar to those reported in the literature, and the phth protons are at -2.3 to -10.1 ppm. Studies on structure, bond valence sum analysis, and magnetic properties indicate the oxidation states of the Mn ions in 6 to be +3, which are also indicated by ESR spectra in dual mode. Ferromagnetic exchange interaction between the Mn(III) sites was observed with J = 1.74 cm(-1). A quasireversible redox pair at -0.29V/0.12V has been assigned to the redox of Mn-2(III)/Mn(III)Mn(II), implying the intactness of the complex backbone in solution.
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34.
  • Noodleman, L., et al. (author)
  • Quantum chemical studies of intermediates and reaction pathways in selected enzymes and catalytic synthetic systems
  • 2004
  • In: Chemical Reviews. - : American Chemical Society (ACS). - 0009-2665 .- 1520-6890. ; 104:2, s. 459-508
  • Research review (peer-reviewed)abstract
    • The catalytic reaction pathways in enzymes synthetic systems were investigated. In this regard, the electron transfer, proton transfer, and charge flow to energetics and structural transformations were discussed. The quantum chemical studies of the reaction mechanisms of the metalloenzymes revealed the intermediates and transition states for the enzymes. The mechanisms of protein tyrosine phosphatases (PTPases) and hammerhead ribozyme chemistry were also presented.
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35.
  • Papp, KA, et al. (author)
  • Early onset of action and efficacy of a combination of calcipotriene and betamethasone dipropionate in the treatment of psoriasis
  • 2003
  • In: Journal of American Academy of Dermatology. - : Elsevier BV. - 0190-9622. ; 48:1, s. 48-54
  • Journal article (peer-reviewed)abstract
    • Background: Calcipotriene and betamethasone dipropionate are topical treatments for psoriasis vulgaris. Their mode of action is different. Improved risk/benefit may result with concomitant use of the two compounds together. A new vehicle has been created with the objective of obtaining optimal stability of both calcipotriene and betamethasone dipropionate in the combination product. Objective. We compared the clinical efficacy of a fixed combination of calcipotriene and betamethasone clipropionate in a new vehicle to calcipotriene in the new vehicle, betamethasone in the new vehicle, and the new vehicle alone. Methods: This was an international, multicenter, prospective, randomized, double-blind, parallel-group, 4-week study in patients with psoriasis vulgaris amenable to topical treatment. Results. The mean percentage reduction in PASI from baseline to end of treatment was 73.2% in the combination group (n = 301), 48.8% in the calcipotriene group (n = 308), 63.1% in the betamethasone dipropionate group (n = 312) and 28.8% in the new vehicle group (n = 107), (P < .001). The mean percentage reduction in PASI during the first week was 48.1%, 28.4%, 41.4%, and 21.5%, respectively (P < .001). Conclusion: A combination product of calcipotriene 50 mug/g and betamethasone dipropionate 0.5 mg/g in the new vehicle shows superior efficacy with a more rapid onset of action than the new vehicle containing either constituent alone in the treatment of psoriasis vulgaris.
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37.
  • Yafa, C., et al. (author)
  • Development of an ombrotrophic peat bog (low ash) reference material for the determination of elemental concentrations
  • 2004
  • In: Journal of Environmental Monitoring. - : Royal Society of Chemistry (RSC). - 1464-0325 .- 1464-0333. ; 6:493, s. 501-
  • Journal article (peer-reviewed)abstract
    • Given the increasing interest in using peat bogs as archives of atmospheric metal deposition, the lack of validated sample preparation methods and suitable certified reference materials has hindered not only the quality assurance of the generated analytical data but also the interpretation and comparison of peat core metal profiles from different laboratories in the international community. Reference materials play an important role in the evaluation of the accuracy of analytical results and are essential parts of good laboratory practice. An ombrotrophic peat bog reference material has been developed by 14 laboratories from nine countries in an inter-laboratory comparison between February and October 2002. The material has been characterised for both acid-extractable and total concentrations of a range of elements, including Al, As, Ca, Cd, Cr, Cu, Fe, Hg, Mg, Mn, Na, Ni, P, Pb, Ti, V and Zn. The steps involved in the production of the reference material (i.e. collection and preparation, homogeneity and stability studies, and certification) are described in detail.
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38.
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39.
  • Ye, L, et al. (author)
  • Thyroid receptor ligands. 1. Agonist ligands selective for the thyroid receptor beta1.
  • 2003
  • In: Journal of Medicinal Chemistry. ; 24;46:9, s. 1580-8
  • Journal article (peer-reviewed)abstract
    • Endogenous thyroid receptor hormones 3,5,3',5'-tetraiodo-l-thyronine (T(4), 1) and 3,5,3'-triiodo-l-thyronine (T(3), 2) exert a significant effects on growth, development, and homeostasis in mammals. They regulate important genes in intestinal, skeletal, and cardiac muscles, the liver, and the central nervous system, influence overall metabolic rate, cholesterol and triglyceride levels, and heart rate, and affect mood and overall sense of well being. The literature suggests many or most effects of thyroid hormones on the heart, in particular on the heart rate and rhythm, are mediated through the TRalpha(1) isoform, while most actions of the hormones on the liver and other tissues are mediated more through the TRbeta(1) isoform of the receptor. Some effects of thyroid hormones may be therapeutically useful in nonthyroid disorders if adverse effects can be minimized or eliminated. These potentially useful features include weight reduction for the treatment of obesity, cholesterol lowering for treating hyperlipidemia, amelioration of depression, and stimulation of bone formation in osteoporosis. Prior attempts to utilize thyroid hormones pharmacologically to treat these disorders have been limited by manifestations of hyperthyroidism and, in particular, cardiovascular toxicity. Consequently, development of thyroid hormone receptor agonists that are selective for the beta-isoform could lead to safe therapies for these common disorders while avoiding cardiotoxicity. We describe here the synthesis and evaluation of a series of novel TR ligands, which are selective for TRbeta(1) over TRalpha(1). These ligands could potentially be useful for treatment of various disorders as outlined above. From a series of homologous R(1)-substituted carboxylic acid derivatives, increasing chain length was found to have a profound effect on affinity and selectivity in a radioreceptor binding assay for the human thyroid hormone receptors alpha(1) and beta(1) (TRalpha(1) and TRbeta(2)) as well as a reporter cell assay employing CHOK1-cells (Chinese hamster ovary cells) stably transfected with hTRalpha(1) or hTRbeta(1) and an alkaline phosphatase reporter-gene downstream thyroid response element (TRAFalpha(1) and TRAFbeta(1)). Affinity increases in the order formic, acetic, and propionic acid, while beta-selectivity is highest when the R(1) position is substituted with acetic acid. Within this series 3,5-dibromo-4-[(4-hydroxy-3-isopropylphenoxy)phenyl]acetic acid (11a) and 3,5-dichloro-4-[(4-hydroxy-3-isopropylphenoxy)phenyl]acetic acid (15) were found to reveal the most promising in vitro data based on isoform selectivity and were selected for further in vivo studies. The effect of 2, 11a, and 15 in a cholesterol-fed rat model was monitored including potencies for heart rate (ED(15)), cholesterol (ED(50)), and TSH (ED(50)). Potency for tachycardia was significantly reduced for the TRbeta selective compounds 11a and 15 compared with 2, while both 11a and 15 retained the cholesterol-lowering potency of 2. This left an approximately 10-fold therapeutic window between heart rate and cholesterol, which is consistent with the action of ligands that are approximately 10-fold more selective for TRbeta(1). We also report the X-ray crystallographic structures of the ligand binding domains of TRalpha and TRbeta in complex with 15. These structures reveal that the single amino acid difference in the ligand binding pocket (Ser277 in TRalpha or Asn331 in TRbeta) results in a slightly different hydrogen bonding pattern that may explain the increased beta-selectivity of 15.
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40.
  • Zabarovska, V, et al. (author)
  • CIS--cloning of identical sequences between two complex genomes
  • 2000
  • In: Chromosome research : an international journal on the molecular, supramolecular and evolutionary aspects of chromosome biology. - : Springer Science and Business Media LLC. - 0967-3849. ; 8:1, s. 77-84
  • Journal article (peer-reviewed)
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41.
  •  
42.
  • Zheng, Li-Rong, et al. (author)
  • Design and implementation of system-on-package for radio and mixed-signal applications
  • 2004
  • In: PROCEEDINGS OF THE SIXTH IEEE CPMT CONFERENCE ON HIGH DENSITY MICROSYSTEM DESIGN AND PACKAGING AND COMPONENT FAILURE ANALYSIS (HDP'04). - NEW YORK : IEEE. - 0780386205 ; , s. 97-104
  • Conference paper (peer-reviewed)abstract
    • Emerging wireless applications for logistics, intelligent home networks, smart dusts, wireless body area networks (WBAN) will need integration and fusion of a diversity of technologies, which may include digital CMOS circuits, analog/RF circuits, sensors/MEMS, embedded software and memories, antenna, displays, polymer, packaging and interconnections, new materials and new integration process. System-on-package (SoP) is considered as a promising solution for the fundamental integration platform for such applications. In this paper, we show how SoP technology can address the integration platform for these applications and how this can be done in a better way than system-on-chip integration. We first demonstrate the integration process of, SoP in liquid-crystal polymer materials. We see that liquid-crystal-polymer is a promising material for low cost RF SoP. We then demonstrate some design examples. The first one is an integrated 5GHz RF receiver front-end in liquid crystal polymer. Due to high quality of passive components in SoP, superior RF performance is found in this module. In the second example, we address several critical design issues for on-chip versus off-chip passives in a multi-band multi-standard radio for beyond 3G applications. We find that not only RF performance can be improved. Cost benefits are also obvious for such a complex radio. Chip-package co-design for smart parasitic absorption is demonstrated through an RF module for an ultrawide band radio in gigabit wireless. Concept of a SoP pacemaker in a WBAN is shown. Finally, we discuss some system level integration issues and we show how a system can be smartly partitioned for SoP so that we can obtain an optimal total solution for low-cost and good-performance wireless integration.
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