bluuebunny/crossref_metadata_2025_split huggingface dataset:
Electric quadrupole and hexadecapole moments for X2CCX2, X = H, F, Cl, Br, and I*
Authors: Karamanis Panaghiotis , Maroulis George 
Published: October 2002

AbstractWe have calculated electric quadrupole and hexadecapole moments for ethene, tetrafluoroethene, tetrachloroethene, tetrabromoethene, and tetraiodoethene. A large basis set of [9s6p5d2f/5s4p2d] size is thought to provide reference near‐Hartree–Fock results for the electric multipole moments of ethene: Θxx=1.34 and \documentclass{article}\pagestyle{empty}\begin{document}$\Theta_{zz}=1.53\ ea_{0}^{2}$\end{document} for the quadrupole Φxxxx=−17.38, Φyyyy=20.29, and \documentclass{article}\pagestyle{empty}\begin{document}$\Phi_{zzzz}=-17.04\ ea_{0}^{4}$\end{document} for the hexadecapole moment (with z as the CC axis and the molecule on the xz plane). The electron correlation correction to the above values is estimated from coupled cluster calculations as Θxx=−0.12 and \documentclass{article}\pagestyle{empty}\begin{document}$\Theta_{zz}=-0.34\ ea_{0}^{2}$\end{document} for the quadrupole and Φxxxx=1.26, Φyyyy=−1.30, and \documentclass{article}\pagestyle{empty}\begin{document}$\Phi_{zzzz}=1.80\ ea_{0}^{4}$\end{document} for the hexadecapole moment. For the halogenated ethenes we have obtained the following quadrupole moment values from second‐order Mø ller–Plesset perturbation theory calculations: Θxx=−1.14 (C2F4), 1.94 (C2Cl4), 3.61 (C2Br4), 6.84 (C2I4) and Θzz=−1.04 (C2F4), −0.41 (C2Cl4), −0.15 (C2Br4), −0.87 (C2I4) \documentclass{article}\pagestyle{empty}\begin{document}$ea_{0}^{2}$\end{document}. © 2002 Wiley Periodicals, Inc. Int J Quantum Chem, 2002
Ab initio quantum mechanical characterization of platinum, palladium, and nickel complexes of L‐ascorbic acid
Authors: Mora M. A. , Raya A. , Mora‐Ramirez M. A. 
Published: October 2002

AbstractElectronic and structural properties of diamine–M ascorbate complexes {M(asc) (N–N)} where M is nickel, palladium, or platinum are studied with the use of ab initio molecular orbital methods at different levels of theory. The properties calculated for the platinum complex are compared with the experimental and theoretical values obtained previously and the agreement between them is shown to be good. Total overlap population values show that the ascorbate acts as a chelating ligand where coordination occurs through one carbon and one oxygen atom. We also present a detailed description of the bonding in order to characterize the intramolecular interactions in the M complexes. © 2002 Wiley Periodicals, Inc. Int J Quantum Chem, 2002
Software algorithm for automatic interpretation of mass spectra of glycerolipids
Authors: Kurvinen J.‐P. , Aaltonen J. , Kuksis A. , Kallio H. 
Published: October 2002

AbstractA new software algorithm for automatic interpretation of mass spectra of glycerolipids has been developed. The algorithm utilizes a user‐specified list of parameters needed to process the spectra. The compounds in mass spectra are identified according to range of measured m/z values, after which the spectra are automatically corrected by the content of naturally occurring isotopes and ion intensities of identified compounds by response correction factors. Automatic processing of the spectra was shown to be accurate and reliable by testing with numerous spectra of glycerophospholipids obtained by liquid chromatography/electrospray ionization mass spectrometry and by comparing the results with manual interpretation of the spectra. If quantitative analysis using internal standards is performed, all the identified compounds in the sample are quantified automatically. A dilution factor may be defined for each sample and is applied to correct the alterations in sample concentration during sample preparation. Processing of several replicate spectra simultaneously produces mean results with standard deviations. The software may also be used to subtract the results of two analyses and to calculate the mean result of replicate subtractions. The algorithm was shown to save time and labor in repetitive processing of mass spectra of similar type. It may be applied to processing of spectra obtained by various mass spectrometric methods. Copyright © 2002 John Wiley & Sons, Ltd.
Hydrophilic interaction liquid chromatography/electrospray mass spectrometry determination of acyclovir in pregnant rat plasma and tissues
Authors: Brown Stacy D. , White Catherine A. , Bartlett Michael G. 
Published: October 2002

AbstractReversed‐phase chromatography is the most common means of separation for small drug molecules. However, polar drugs may suffer from poor retention and peak shape in reversed‐phase high‐performance liquid chromatography (RP‐HPLC). Hydrophilic interaction liquid chromatography (HILIC) provides a viable alternative to RP‐HPLC and is an excellent way to separate polar compounds. This paper describes a HILIC/ESI‐MS/MS assay for the determination of acyclovir from rat plasma, amniotic fluid, placental tissue, and fetal tissue. The isocratic separation utilizes an underivatized silica column with an acetonitrile/formate buffer mobile phase (80:20). The method is validated over a range of 50 ng/mL to 50 µg/mL with % error and % relative standard deviation of <15% over 3 days. All samples are prepared by acetonitrile protein precipitation, which yields high recovery (>84% for acyclovir). This assay can be applied to the pharmacokinetic study of the placental transfer of acyclovir. Copyright © 2002 John Wiley & Sons, Ltd.
Sodium‐tolerant matrix for matrix‐assisted laser desorption/ionization mass spectrometry and post‐source decay of oligonucleotides
Authors: Lavanant Hélène , Lange Catherine 
Published: October 2002

AbstractA mixture of 2′,4′,6′‐trihydroxyacetophenone in acetonitrile and aqueous triammonium citrate solution in a 1:1 molar proportion (0.2 M concentration) was found to be a good matrix for the detection of synthetic oligodeoxynucleotide samples. A high proportion of volatile solvent as well as the high salt content ensure fast co‐crystallization of the matrix, co‐matrix and analyte molecules. Matrix‐assisted laser desorption/ionization (MALDI) mass spectra obtained in negative ion reflectron mode from samples prepared with this protocol show deprotonated molecules [M − H]−, rather than sodium adducts, as the most abundant ions even when up to 50 mM of sodium chloride is present in the sample. The matrix is shown to be effective for low mass modified single nucleotides as well as for longer oligodeoxynucleotides (up to 18mer). Post‐source decay (PSD) mass spectra can also be obtained by increasing the laser fluence. Simple sequence information such as the identity and localization of a deleted base or the 5′/3′ orientation can then easily be obtained. The calibration method and mass accuracy required are discussed depending on the type of information required. Copyright © 2002 John Wiley & Sons, Ltd.
“Trampeg”: An MPEG‐2 real‐time software transcoder for low‐bit‐rate transmission
Authors: Akutsu Takashi , Kimata Hideaki , Shimizu Atsushi , Yashima Yoshiyuki , Kobayashi Naoki 
Published: October 2002

AbstractIn the audiovisual handling of content coded by MPEG‐2 transmitted over various kinds of networks such as the Internet or LAN, transformation of coding bit rates or transcoding is necessary. The simplest transcoding method is that of decoding MPEG‐2 completely and then reencoding it at a lower bit rate. However, real‐time processing of this method on a commonly used PC is difficult since the level of operations or the computational complexity for coding is high. However, if using the before‐transformation coding information decreases the computational complexity, real‐time transformation (transcoding) by software becomes possible. In this study, the Trampeg software transcoder (transcoder for MPEG‐2) capable of real‐time transcoding MPEG‐2 with high quality has been developed. The applications, design guidelines, and processing algorithms of Trampeg are presented in this paper. The results of evaluation for operation of the system over a real PC have verified that an MPEG‐2 system stream input via a network can be transcoded in real time and the transcoded low‐rate stream can be transmitted directly to a streaming server. © 2002 Wiley Periodicals, Inc. Syst Comp Jpn, 33(12): 77–86, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/scj.10062
A machinery control system using mobile agents
Authors: Wada Hidehiko , Sakuraba Yuichi , Negishi Masako , Yamakawa Toshiharu 
Published: October 2002

AbstractFlexibility will be one of the key features in future manufacturing systems because the environments that surround manufacturing systems are rapidly changing from day to day. To satisfy this requirement, we propose an autonomous decentralized system using agents. In manufacturing systems using agents, the basic concept should be based on a target product and on work having some information moving around in the system. To realize this concept, we introduce several agents called product agent or machine agent. To verify our proposed concept and architecture, we developed a prototype system. This system was for the Shape Deposition Manufacturing Laboratory of the Robotics Institute at Carnegie Mellon University. © 2002 Wiley Periodicals, Inc. Syst Comp Jpn, 33(12): 47–57, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/scj.10122
X‐ray photoelectron spectroscopy as a method to control the formation of metal–carbon tubules
Authors: Shabanova I. N. , Makarova L. G. , Kodolov V. I. , Kuznetsov A. P. 
Published: October 2002

AbstractIn the given paper the use of x‐ray photoelectron spectroscopy as a means to control the formation of metal–carbon tubules by low‐energy synthesis from multi‐ring hydrocarbons in active media is discussed. The dependence of C–C bond formation on the content of the initial components in mixtures prepared from fine powders of anthracene and metal chloride (Me = Mn, Co, Ni) was studied by means of x‐ray photoelectron spectra. Based on the results of x‐ray photoelectron spectroscopy, the assumption about the mechanisms of formation and growth of tubules was made, confirmed by the results obtained by transmission electron microscopy. Copyright © 2002 John Wiley & Sons, Ltd.
Atomic‐scale investigation of the localized corrosion of passivated nickel surfaces
Authors: Maurice V. , Klein L. H. , Marcus P. 
Published: October 2002

AbstractIn situ scanning tunnelling microscopy measurements of the localized corrosion of Ni(111) surfaces passivated in a chloride‐free sulphuric acid solution and subsequently exposed to chloride (0.05 M) are reported. The results support the deterministic role of the structure of the passivated surface on the dissolution in the passive state, independent of the addition of chloride in the electrolyte. The atomic lattice of the passive film formed in the absence of chloride is unmodified after the addition of chloride. At the investigated potential of +0.85 VSHE (0.05 V below the stable pitting potential), the dissolution proceeds by a two‐dimensional step flow process that is dependent on the step orientation, the steps oriented along the closed‐packed directions dissolving much less rapidly than the steps oriented along no well‐defined directions of the oxide lattice. The dissolution rate of the oxide lattice is ∼6 NiO ‘molecules’ s−1, independent of the presence of chloride. The comparison with the rate of dissolution that can be estimated from the measured electrochemical current density in the passive state suggests that the dissolution of the oxide lattice of the passive film is not the major anodic reaction in the passive state. Copyright © 2002 John Wiley & Sons, Ltd.
Chrome‐free pretreatment for aluminium composites
Authors: Hamdy Abdel Salam , Beccaria Anna Maria 
Published: October 2002

AbstractThe effect of manganese pretreatment on the corrosion behaviour of AA6061 T6–10% Al2O3 metal–matrix composite was investigated in aerated aqueous 3.5% NaCl solution using electrochemical impedance spectroscopy (EIS). The corrosion inhibition characteristics were studied for two series of manganese‐pretreated specimens after 30 days of immersion in NaCl solution at different pH, pretreatment times and different surface preparation prior to manganese pretreatment. Polarization tests were used to investigate the perfect passivity domain after 60 days of immersion in NaCl. Results showed that the specimens treated in KMnO4 + NaCl, in pure KMnO4 solution for a long time (1–7 days) at neutral pH and in pure KMnO4 solution at pH 8 for a short time (<1 h) suffered from pitting, crevice or general corrosion. Conversely, the specimens treated in pure KMnO4 solution for 3 h at pH 8 or at neutral pH did not show any sign of corrosion. X‐ray photoelectron spectroscopy revealed the presence of a high percentage of Al2O3 in addition to Mn oxide as a compact surface film. A promising corrosion resistance was obtained by sealing in a silicate solution for 2 min after treatment in pure KMnO4 solution. Microscopic examinations showed that silicon plays an important role in improving the protective power of the passive film by repairing the pitting results from chloride ion attack. Copyright © 2002 John Wiley & Sons, Ltd.
Elastic electron backscattering from silicon surfaces: effect of surface roughness
Authors: Zemek J. , Jiricek P. , Jablonski A. , Lesiak B. 
Published: October 2002

AbstractThe inelastic mean free paths (IMFPs) in Si have been investigated frequently using experimental and theoretical approaches. At present, the only experimental method providing the IMFPs is elastic peak electron spectroscopy (EPES). However, in previous studies, a scatter between published data in Si was observed that originated from the statistical and systematic error of the EPES method. In the present work, systematic study has been carried out on the influence of surface roughness on the electron IMFPs determined by the EPES method using a Cu standard. The Si surfaces (polished and ground) characterized by surface roughnesses of 5.5 and 760.0 nm have been studied under electron emission angles of 35° and 70° with respect to the surface normal. It has been shown that these differences in surface roughness do not affect the measured IMFPs. Slight deviations in the IMFPs measured at two geometries were observed for low electron energies, indicating an increase of IMFPs at electron emission close to glancing angle due to the lower densities at the surface with respect to the bulk and the smaller elastic cross‐sections used in the EPES calculations. Copyright © 2002 John Wiley & Sons, Ltd.
AES characterization of oxide grains formed on ductile cast irons in exhaust environments
Authors: Tholence F. , Norell M. 
Published: October 2002

AbstractCast alloys (SiMo and Ni‐resist) were oxidized at 850°C for 50 h in dry air and synthetic diesel exhaust gases. High‐resolution AES analysis and SEM studies on sections of the inner oxides showed that, for both alloys, thicker silicon‐containing oxides layers were formed at metal/oxide interfaces in diesel than in air. For SiMo, fayalite appeared to precipitate within this layer in diesel gases, thus lowering its protectiveness. Further out, silica may reprecipitate. Where the austenitic Ni‐resist failed to maintain a protective interfacial oxide, a highly irregular oxide/metal interface led to metallic Ni‐rich particles becoming trapped in the oxide. Copyright © 2002 John Wiley & Sons, Ltd.
The Cochrane Collaboration – how is it progressing?
Authors: Laupacis Andreas 
Published: October 2002

AbstractDuring the last seven years, the Cochrane Collaboration has rapidly developed into an important international organization, producing high quality systematic reviews of randomized trials. Challenges, which it will likely meet, include maintaining the quality of the reviews, ensuring that reviews are done of the most common therapies for important diseases, securing stable funding, and making the format of the reviews more accessible for the average clinician. Copyright © 2002 John Wiley & Sons, Ltd.
Industry perspectives on ICH guidelines
Authors: Rockhold Frank W. 
Published: October 2002

AbstractIn 1990 the International Conference on Harmonization (ICH) effort was begun with the intent of standardizing the drug registration and approval process. The need to rationalize and harmonize regulation was driven by concerns over rising costs of health care, escalation of the cost of research and development and the need to meet the public expectation that there should be a minimum delay in making safe and efficacious new treatments available to patients in need. Since most regulatory agencies have limited resources to interact with sponsor companies, standardized guidelines would help expedite communications with companies at the programme design stage. The ICH is a joint initiative involving both regulators and industry as partners in scientific and technical discussions of the testing procedures which are required to ensure the safety and efficacy of medicines. While all regions of the world have some input to the process, the primary development of the guidelines is derived from industry and regulatory representatives from Europe, Japan and the United States. Much progress has been made in the ten years since the initiation of the ICH, but the implementation and maintenance of the guidelines are in the early stages for most if not all of the published guidelines. If the guidelines do not gain a solid foothold early on, then drift between the regions in use of the guidelines will defeat the goals of the ICH. While the ICH covers the entire drug development process, this paper will review the guidelines that pertain most closely to clinical trials and their use in the drug registration process. Some of the guidelines have been approved and some are still in the development stage. Copyright © 2002 John Wiley & Sons, Ltd.
Role of brain α1B‐adrenoceptors in modafinil‐induced behavioral activity
Authors: Stone Eric A. , Cotecchia Susanna , Lin Yan , Quartermain David 
Published: October 2002

AbstractThese studies show that either central pharmacological blockade or genetic ablation of α1B‐adrenoceptors markedly attenuates the behavioral activation caused by modafinil, implicating these receptors in the drug's action. Synapse 46:269–270, 2002. © 2002 Wiley‐Liss, Inc.
Gamma‐vinyl GABA, an irreversible inhibitor of GABA transaminase, alters the acquisition and expression of cocaine‐induced sensitization in male rats
Authors: Gardner Eliot L. , Schiffer Wynne K. , Horan Bryan A. , Highfield David , Dewey Stephen L. , Brodie Jonathan D. , Ashby Charles R. 
Published: October 2002

AbstractWe examined the effect of (±)‐gamma‐vinyl GABA (GVG, Vigabatrin), an irreversible inhibitor of the enzyme GABA transaminase, on the acquisition and expression of cocaine‐induced sensitization in albino male Sprague‐Dawley rats. Animals received a single injection of 1 ml/kg i.p. of 0.9% saline or 15 mg/kg i.p. of (−)‐cocaine and locomotor activity was assessed using automated locomotor cages and stereotyped behaviors were scored using a 4‐point rating scale (Day 1). Subsequently, animals were given 15 mg/kg i.p. of cocaine every 48 h in their home cage for 1 week (Days 3, 5, and 7) and then given no treatment for 1 week. A challenge injection of 15 mg/kg i.p. of cocaine, but not vehicle, produced a significant increase in locomotor activity and stereotyped behaviors on Day 15 compared to animals that received cocaine on Day 1. Administration of 75 mg/kg i.p. of GVG 2.5 h before the cocaine injections did not significantly alter the acquisition of cocaine‐induced locomotor sensitization. However, 150 mg/kg i.p. of GVG significantly attenuated the acquisition of cocaine‐induced locomotor sensitization. Administration of 150 mg/kg i.p. of GVG 2.5 h before the cocaine challenge injection on Day 15 significantly attenuated the expression of cocaine‐induced locomotor sensitization. Acquisition and expression of cocaine‐induced sensitization of stereotypy was also significantly attenuated by 150 mg/kg i.p. of GVG. Since sensitization may be one of the factors involved in relapse to drug use, the present results, in combination with previous findings that GVG blocks the rewarding and incentive motivating effects of cocaine, suggest that GVG might prove useful in the treatment of cocaine addiction. Synapse 46:240–250, 2002. © 2002 Wiley‐Liss, Inc.
Widespread but regionally specific effects of experimenter‐ versus self‐administered morphine on dendritic spines in the nucleus accumbens, hippocampus, and neocortex of adult rats
Authors: Robinson Terry E. , Gorny Grazyna , Savage Virginia R. , Kolb Bryan 
Published: October 2002

AbstractWe studied the effects of self‐administered (SA) vs. experimenter‐administered (EA) morphine on dendritic spines in the hippocampal formation (CA1 and dentate), nucleus accumbens shell (NAcc‐s), sensory cortex (Par1 and Oc1), medial frontal cortex (Cg3), and orbital frontal cortex (AID) of rats. Animals in the SA group self‐administered morphine in 2‐h sessions (0.5 mg/kg/infusion, i.v.) for an average of 22 sessions and animals in the EA group were given daily i.v. injections of doses that approximated the total session dose for matched rats in Group SA (average cumulative dose/session of 7.7 mg/kg). Control rats were given daily i.v. infusions of saline. One month after the last treatment the brains were processed for Golgi‐Cox staining. In most brain regions (Cg3, Oc1, NAcc‐s) morphine decreased the density of dendritic spines, regardless of mode of administration (although to a significantly greater extent in Group SA). However, only SA morphine decreased spine density in the hippocampal formation and only EA morphine decreased spine density in Par1. Interestingly, in the orbital frontal cortex morphine significantly increased spine density in both Groups SA and EA, although to a much greater extent in Group SA. We conclude: 1) Morphine has persistent (at least 1 month) effects on the density of dendritic spines in many brain regions, and on many different types of cells (medium spiny neurons, pyramidal cells, and granule cells); 2) The effect of morphine on spine density (and presumably synaptic organization) varies as a function of both brain region and mode of drug administration; and 3) The ability of morphine to remodel synaptic inputs in a regionally specific manner may account for the many different long‐term sequelae associated with opioid use. Synapse 46:271–279, 2002. © 2002 Wiley‐Liss, Inc.