bluuebunny/crossref_metadata_2025_split huggingface dataset:
Feature extraction of AR as a performance index for load frequency controls of interconnected power systems
Authors: Yorino Naoto , Zoka Yoshifumi , Nakanishi Koichi , Nakagawara Satohiko , Kamei Yoshifumi , Sasaki Hiroshi 
Published: October 2005

AbstractRecently, the evaluation of control performances of interconnected power systems has become an important issue with respect to individual load frequency controls. Several performance measures are in practical use such as Area Control Error (ACE), Mutual Aid Criterion (MAC), and Control Performance Standard (CPS). Area Requirement (AR) is an alternative expression for ACE, where AR=−ACE. However, the characteristics of these indices have not been sufficiently studied as far as the authors know. In particular, this is the case for their dynamic behavior against random load disturbances. This paper investigates the performance index, AR, through analysis of two‐area systems. Major dynamic elements of interconnected systems affecting the frequency are taken into account to investigate responses of the system against load disturbances. The analysis shows that, when new systems are interconnected, the smaller system tends to require more effort of control against load disturbances to keep the same value of the performance indices. © 2005 Wiley Periodicals, Inc. Electr Eng Jpn, 154(1): 20–28, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20233
Synthesis, Characterization, and Reactivity of Neutral and Cationic Pd–C,N,N Pincer Complexes
Authors: Bianchini Claudio , Lenoble Géraldine , Oberhauser Werner , Parisel Sébastien , Zanobini Fabrizio 
Published: October 2005

AbstractThe ortho‐palladation of the iminophosphane ligand 6‐phenyl‐2‐[(2,6‐diisopropylphenyl)imino]pyridine (HL) with Pd(OAc)2 and PdCl2(PhCN)2 in benzene yields the neutral Pd–C,N,N pincer complexes Pd(OAc)(κ3‐C,N,N‐L) (1) and PdCl(κ3‐C,N,N‐L) (2), respectively. In the presence of NaBAr′4 [Ar′ = 3,5‐(CF3)2C6H3], 2 reacts in CH2Cl2 with MeCN, PPh3, or PH[o‐MeO(C6H4)]2 to give the cationic palladium(II) pincer complexes [Pd(CH3CN)(κ3‐C,N,N‐L)]BAr′4 (3), [Pd(PPh3)(κ3‐C,N,N‐L)]BAr′4 (4) and {Pd[PH(o‐MeOC6H4)2](κ3‐C,N,N‐L)}BAr′4 (5), respectively. Complexes 1–5 have been characterized by multinuclear NMR and IR spectroscopy. The solid‐state structures of 1 and 2 have been determined by single‐crystal X‐ray diffraction techniques. Both the neutral compounds 1 and 2 and the cationic derivatives 3, 4, and 5 were tested as catalyst precursors for the Suzuki cross‐coupling of 4‐bromo‐ and 4‐chloroacetophenone with phenylboronic acid. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Crystal Structure and Magnetic Behaviour of the New Gadolinium Complex Compound Gd2(ClH2CCOO)6(bipy)2
Authors: John Daniela , Urland Werner 
Published: October 2005

AbstractSingle crystals of the title compound have been obtained by reaction of Gd3(ClH2CCOO)9(H2O)5 with 2,2′‐bipyridyl (bipy) in a solution of ethanol and water. Gd2(ClH2CCOO)6(bipy)2 crystallises in the triclinic space group P$\bar {1}$ (Z = 2) with a = 959.5(3) pm, b = 980.9(3) pm, c = 1163.9(4) pm, α = 68.67(3) °, β = 84.82(4)° and γ = 82.47(4)°. The crystal structure is built up of discrete molecules of dinuclear Gd3+–Gd3+ units. The corresponding residual (all data) for the refined structure is 4.46 %. The magnetic behaviour of the compound was investigated in the temperature range of 1.76–300 K. The magnetic data were interpreted considering exchange interactions within the dimeric unit (Jex = –0.020 cm–1). (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
The Osher scheme for non‐equilibrium reacting flows
Authors: Suresh Ambady , Liou Meng‐Sing 
Published: October 2005

AbstractAn extension of the Osher upwind scheme to non‐equilibrium reacting flows is presented, Owing to the presence of source terms, the Riemann problem is no longer self‐similar and therefore its approximate solution becomes tedious. With simplicity in mind, a linearized approach which avoids an iterative solution is used to define the intermediate states and sonic points. The source terms are treated explicitly. Numerical computations are presented to demonstrate the feasibility, efficiency and accuracy of the proposed method. The test problems include a ZND (Zeldovich‐Neumann‐Doring) detonation problem for which spurious numerical solutions which propagate at mesh speed have been observed on coarse grids. With the present method, a change of limiter causes the solution to change from the physically correct CJ detonation solution to the spurious weak detonation solution.
Prediction of turbulent offset jet flows with an assessment of QUICKER scheme
Authors: Koo Hyeong‐Mo , Park Seung O. 
Published: October 2005

AbstractThe QUICKER scheme extended for non‐uniform rectangular grid systems has been applied to predict the turbulent offset jet flows. Computational results obtained with the QUICKER scheme are compared with those from the skew‐upwind and the hybrid schemes. Computational results include the reattachment length, the velocity profile, the axial velocity decay curve, and the shear stress distribution. In the sense of an overall agreement with the experimental data, the QUICKER scheme is found to be superior to the other two schemes. Boundary conditions are carefully set up to account for various flow conditions. Special attention has been given to the set‐up of entrainment boundary condition. It is emphasized that the numerical diffusion due to streamline‐to‐grid skewness far exceeds the turbulent diffusion in offset jet flows; therefore, a numerical scheme that would minimize the numerical diffusion is a prerequisite for a better prediction of the turbulent offset jet flows.
Integral transform solution for the lid‐driven cavity flow problem in streamfunction‐only formulation
Authors: Guerrero J. S. Pérez , Cotta R. M. 
Published: October 2005

AbstractThe basic ideas in the generalized integral transform technique are further advanced to allow for the hybrid numerical‐analytical solution of the two‐dimensional steady Navier‐Stokes equations in streamfunction‐only formulation. The classical lid‐driven square cavity problem is selected for illustration of the approach. The corresponding biharmonic‐type non‐linear partial differential equation for the streamfunction is integral transformed in one of the co‐ordinates and an infinite system of coupled non‐linear ODEs for the transformed potential results in the other independent variable. Upon truncation to an appropriate finite order, the ODE system is numerically solved by well‐established algorithms with automatic error control devices. The convergence behaviour of the eigenfunction expansion is demonstrated and reference results are provided for typical values of Reynolds number.
A stable high‐order method for the heated cavity problem
Authors: Choo Joshua Y. , Schultz D. H. 
Published: October 2005

AbstractA fourth‐order method, without using extrapolation, is developed for the steady‐state solution of a non‐linear system of three simultaneous partial differential equations for the flow of a fluid in a heated closed cavity. The method is a finite difference method which has converged for all Rayleigh numbers Ra of physical interest and all Prandtl numbers Pr attempted. The results are presented and compared with some of the accurate results available in de Vahl Davis and Jones, Shay and Schultz, and Dennis and Hudson. The method used to develop the fourth‐order method presented in this paper can be used to develop high‐order methods for other partial differential equations. The method was developed to be stable without using the upwinding technique.
A global approach to error estimation and physical diagnostics in multidimensional computational fluid dynamics
Authors: Haworth D. C. , El Tahry S. H. , Huebler M. S. 
Published: October 2005

AbstractAn approach for simultaneously assessing numerical accuracy and extracting physical information from multidimensional calculations of complex (engineering) flows is proposed and demonstrated. The method is based on global balance equations, i.e. volume‐integrated partial differential equations for primary or derived physical quantities of interest. Balances can be applied to the full computational domain or to any subdomain down to the single‐cell level. Applications to in‐cylinder flows in reciprocating engines are used for illustration. It is demonstrated that comparison of the relative magnitude of the terms in the balances provides insight into the physics of the flow being computed. Moreover, for quantities that are not conserved at the cell or control volume level in the construction of the numerical scheme, the imbalance allows a direct assessment of numerical accuracy in a single run using a single mesh. The mean kinetic energy imbalance is shown to be a particularly sensitive indicator of numerical accuracy. This simple and powerful diagnostic approach can be implemented for finite‐difference, finite‐volume or finite‐element methods.
Linear stability of swirling flows computed as solutions to the quasi‐cylindrical equations of motion
Authors: Spall Robert E. 
Published: October 2005

AbstractThe linear stability of numerical solutions to the quasi‐cylindrical equations of motion for swirling flows is investigated. Initial conditions are derived from Batchelor's similarity solution for a trailing line vortex. The stability calculations are performed using a second‐order‐accurate finite‐difference scheme on a staggered grid, with the accuracy of the computed eigenvalues enhanced through Richardson extrapolation. The streamwise development of both viscous and inviscid instability modes is presented. The possible relationship to vortex breakdown is discussed.
Multilevel methods for temporal and spatial flow transition simulation in a rough channel
Authors: Liu Zhining , Liu Zhixing , Liu Chaoqun , McCormick Steve 
Published: October 2005

AbstractWe investigate the instability of 2D incompressible flows in a rough planar channel by tracking the growth of the unstable mode in its early stage. We develop both second‐ and fourth‐order finite difference methods on a staggered grid, together with a fully implicit time‐marching scheme, using grid generation to accommodate fairly general geometries. A multigrid full approximation scheme based on the line‐distributive relaxation method is used for fast convergence. For a 2D smooth channel, numerical results show good agreement with the analytic solution obtained from linear theory for small disturbances. Numerical results for a 2D channel with one and two roughness elements are analysed by Fourier analysis. They show how the roughness elements affect the growth of the perturbation.
Numerical simulation of complex flows of non‐Newtonian fluids using the stream tube method and memory integral constitutive equations
Authors: Bereaux Yves , Clermont Jean‐Robert 
Published: October 2005

AbstractIn this paper a memory integral viscoelastic equation is considered for simulating complex flows of non‐Newtonian fluids by stream tube analysis. A formalism is developed to take into account co‐deformational memory equations in a mapped computational domain where the transformed streamlines are parallel and straight. The particle‐tracking problem is avoided. Evolution in time and related kinematic quantities involved with a K‐BKZ integral constitutive model are easily taken into account in evaluating the stresses. Successive subdomains, the stream tubes, may be considered for computing the main flow in abrupt axisymmetric contractions from the wall to the central flow region. The ‘peripheral stream tube’ close to the duct wall is determined by developing a non‐conventional modified Hermite element. A mixed formulation is adopted and the relevant non‐linear equations are solved numerically by the Levenberg‐Marquardt algorithm. Although the singularity at the section of contraction is not involved explicitly, the results obtained for the peripheral stream tube clearly show the singularity effects and the extent of the recirculating zone near the salient corner. The algorithm is stable even at high flow rates and provides satisfactory solutions when compared with similar calculations in the literature.
Inhibitory effect of minocycline on amyloid β fibril formation and human microglial activation
Authors: Familian Atoosa , Boshuizen Ronald S. , Eikelenboom Piet , Veerhuis Robert 
Published: October 2005

AbstractMinocycline, a derivative of the antibiotic tetracycline, displays neuroprotective properties in various models of neurodegenerative diseases and is now used in clinical trials, because of its relative safety and tolerability. Minocycline passes the blood‐brain barrier and is presumed to inhibit microglial activation. In Alzheimer's disease brain, a number of proteins, including serum amyloid P component (SAP) and complement factors such as C1q, accumulate in amyloid β (Aβ) plaques. In a previous study, SAP and C1q were found to be required for clustering of activated microglia in Aβ plaques. Furthermore, SAP and C1q enhanced Aβ fibril formation and Aβ mediated cytokine release by human microglia in vitro. In the present study, we report that tetracycline and minocycline dose‐dependently reduce TNF‐α and IL‐6 release by adult human microglia upon stimulation with a combination of Aβ, SAP, and C1q. In addition, minocycline and to a lesser extent tetracycline inhibit fibril formation of Aβ as determined in a thioflavin‐S‐based fluorescence test. This inhibitory effect was observed with Aβ alone as well as with Aβ in combination with SAP and C1q. Our data suggest that minocycline and tetracycline at tolerable doses can inhibit human microglial activation. This activity in part is exerted by inhibition of (SAP and C1q enhanced) Aβ fibril formation. © 2005 Wiley‐Liss, Inc.
A customized retroviral vector confers marker gene expression in osteoclast lineage cells
Authors: Selski Daniel J. , Clohisy Denis R. 
Published: October 2005

AbstractOsteoclasts play a seminal role in many skeletal diseases and therefore are candidates for cell‐based gene delivery systems to treat disorders of bone. As an initial step toward developing osteoclast‐mediated gene delivery systems, we have made and analyzed a customized Molony–Murine leukemia virus (MMLV)‐based retroviral vector containing elements of the osteoclast‐specific tartrate‐resistant acid phosphatase (TRAP) gene. RAW 264.7 cells were transduced with the customized vector (E3) and differentiated along macrophage or osteoclast lineages. E3 contained a truncated form of the human nerve growth factor receptor (NGFR) as a reporter gene. NGFR expression increased with RANK‐ligand (RANK‐L) treatment but not with macrophage (γ‐IFN/LPS treatment) differentiation. Enhanced NGFR expression peaked 48 h after RANK‐L treatment. Electrophoretic mobility shift assays (EMSA) analysis of the TRAP gene regulatory elements in E3 identified a single 27 bp DNA probe, which specifically bound protein from RANK‐L‐treated cells. DNA sequence revealed AP‐1 binding sites, and analysis with mutant probes implied that the sites were functional. EMSA supershift analysis identified Fos protein interacting with the 27 bp probe. In summary, insertion of sequence −962 to −868 from the TRAP gene into the U3 region of the MMLV LTR confers RANK‐L induced retroviral gene expression via Fos family protein interaction at AP‐1 sites. J. Cell. Biochem. © 2005 Wiley‐Liss, Inc.
Tumor necrosis factor‐related apoptosis‐inducing ligand (TRAIL) regulates endothelial nitric oxide synthase (eNOS) activity and its localization within the human vein endothelial cells (HUVEC) in culture
Authors: Di Pietro Roberta , Mariggiò Maria A. , Guarnieri Simone , Sancilio Silvia , Giardinelli Annalisa , Di Silvestre Sara , Consoli Agostino , Zauli Giorgio , Pandolfi Assunta 
Published: October 2005

AbstractWe have recently demonstrated that tumor necrosis factor‐related apoptosis‐inducing ligand (TRAIL) increases endothelial nitric oxide synthase (eNOS) phosphorylation, NOS activity, and nitric oxide (NO) synthesis in cultured human umbilical vein endothelial cells (HUVEC), without inducing apoptotic cell death. Although an important factor that regulates eNOS activity is its localization within the cells, little is known about the role of TRAIL in the regulation of eNOS trafficking among cellular compartments and the cytoskeleton involvement in this machinery. Then, we did both quantitative and semi‐quantitative evaluations with biochemical assays and immune fluorescence microscopy in the presence of specific inhibitors of NOS activity as well as of cytoskeletal microtubule structures. In our cellular model, TRAIL treatment not only increased NO levels but also caused a time‐dependent NO migration of fluorescent spots from the plasma membrane to the inner part of the cells. In unstimulated cells, most of the eNOS was localized at the cell membranes. However, within 10 min following addition of TRAIL, nearly all the cells showed an increased cytoplasm localization of eNOS which appeared co‐localized with the Golgi apparatus at a higher extent than in unstimulated cells. These effects were associated to an increased formation of trans‐cytoplasm stress fibers with no significant changes of the microtubule network. Conversely, microtubule disruption and Golgi scattering induced with Nocodazole treatment inhibited TRAIL‐increased NOS activity, indicating that, on cultured HUVEC, TRAIL ability to affect NO production by regulating eNOS sub‐cellular distribution is mediated by cytoskeleton and Golgi complex modifications. J. Cell. Biochem. 97: 782–794, 2006. © 2005 Wiley‐Liss, Inc.
Modifications of orientational dependence of microscopic magnetic resonance imaging T2 anisotropy in compressed articular cartilage
Authors: Alhadlaq Hisham A. , Xia Yang 
Published: October 2005

AbstractPurposeTo investigate the compression‐induced changes in the orientational characteristics in T2 anisotropy of articular cartilage using microscopic magnetic resonance imaging (μMRI).Materials and MethodsSix beagle specimens were subjected to various levels of strain (0% to 27%) and were imaged at a minimum of two orientations (0° and 55°). Two specimens at 14% and 27% strain were imaged at every 5° increment over the first quadrant of the angular space. Quantitative two‐dimensional T2 images and three‐dimensional T2 anisotropy maps of cartilage were constructed at a 19.8‐μm in‐depth resolution.ResultsThe load‐induced laminar appearance of cartilage at the magic angle became more distinct as the strain level increased. T2 anisotropy maps of cartilage at 14% and 27% strain exhibited load‐induced modifications in the collagen fibril ultrastructure, with a new peak toward the cartilage‐bone interface and alterations to orientational dependence of T2 anisotropy.ConclusionDistinct alternations in the orientational dependence of μMRI T2 anisotropy reflect the organizational modification of the collagen matrix due to external loading. This approach could become useful in detecting changes in cartilage's macromolecular structure due to injury or diseases. J. Magn. Reson. Imaging 2005. © 2005 Wiley‐Liss, Inc.
Nonacid cleavable detergents applied to MALDI mass spectrometry profiling of whole cells
Authors: Norris Jeremy L. , Hangauer Matthew J. , Porter Ned A. , Caprioli Richard M. 
Published: October 2005

AbstractAlthough cleavable detergents were first synthesized a number of years ago, they have only recently been successfully applied to problems involving biological molecules. Recent reports have demonstrated that these compounds are useful for applications involving both 2D PAGE and mass spectrometry. However, most cleavable surfactants have utilized acid‐labile functional groups to affect cleavage. In applications where extreme pH is required, acid cleavable detergents have limited usefulness. We report the synthesis of fluoride cleavable silane compounds and photolabile cinnamate esters as cleavable detergents having alternative cleavage chemistries than previously reported cleavable detergents. These compounds were applied to whole cell analysis using MALDI mass spectrometry, and it was demonstrated that their use results in an increase in the number of proteins analyzed by increasing protein solubility. Copyright © 2005 John Wiley & Sons, Ltd.
Theoretical study of the gas‐phase structures of sodiated and cesiated leucine and isoleucine: zwitterionic structure disfavored in kinetic method experiments
Authors: Rožman Marko 
Published: October 2005

AbstractThe most stable charge‐solvated (CS) and zwitterionic (ZW) structures of sodiated and cesiated leucine and isoleucine were studied by density functional theory methods. According to the Boltzmann distribution in gas phase, both forms of LeuNa+ and IleNa+ exist, but in LeuCs+ and IleCs+, the ZW forms are dominant. Results for the sodiated compounds are consistent with the relationship found between decrease in relative stability of CS versus ZW form and aliphatic amino acid side chain length. The observed degeneracy in energy for IleNa+ conformers is at odds with kinetic method results. Additional calculations showed that kinetic method structural determinations for IleNa+ do not reflect relative order of populations in the lowest energy conformers. Since complexation of cationized amino acids into ion‐bound dimers disfavors ZW structure by ∼8 kJ mol−1, it is suggested that for energy close conformers of sodium‐cationized amino acids, the kinetic method may not be reliable for structural determinations. Copyright © 2005 John Wiley & Sons, Ltd.
Influence of initial charge state on fragmentation patterns for noncovalent drug/DNA duplex complexes
Authors: Keller Karin M. , Zhang Junmei , Oehlers Leon , Brodbelt Jennifer S. 
Published: October 2005

AbstractThe charge state–dependent dissociation of various DNA duplexes and drug/duplex complexes has been investigated using collisionally activated dissociation (CAD) in a quadrupole ion trap mass spectrometer (QIT‐MS). Several non‐self‐complementary 14‐residue oligonucleotides were employed, in addition to an array of known DNA‐interactive ligands, including the intercalators daunomycin and nogalamycin, as well as the minor groove binding agents distamycin, netropsin, 4′,6‐diamidino‐2‐phenylindole, and Hoechst 33342. In general, the dissociation pathways exhibited by both the duplexes and the drug/duplex complexes were found to be markedly sensitive to initial charge state. Time‐ and activation voltage–independent duplex strand separation predominated for higher charge states, which was interpreted to be a result of internal Coulombic repulsion or partial unzipping in the interface, while time‐ and activation voltage–dependent covalent cleavage predominated for lower charge states. The identity of the drug and the sequence of the duplex were both found to affect the competition between different dissociation processes. The dissociation pathways for the lower charge state complexes are probably more reflective of specific drug–DNA interactions because Coulombic and/or conformational effects are less marked for these precursors. Copyright © 2005 John Wiley & Sons, Ltd.