bluuebunny/crossref_metadata_2025_split huggingface dataset:
4‐Hydroxy‐2‐quinolones. Part 110. Bromination of 1‐R‐4‐Hydroxy‐2‐oxo‐1,2‐dihydroquinoline‐3‐carboxylic Acid Anilides.
Authors: Ukrainets I. V. , Tkach A. A. , Sidorenko L. V. , Gorokhova O. V. 
Published: June 2007

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Investigation on 2,3′‐Biquinolyl Series. Part 21. Reactions of 1′‐Alkyl‐4′‐aryl‐1′,4′‐dihydro‐2,3′‐biquinolyls and 1′‐Alkyl‐2′‐aryl‐1′,2′‐dihydro‐2,3′‐biquinolyls with Sulfur.
Authors: Moiseev D. V. , Goncharov V. I. , Aksenov A. V. 
Published: June 2007

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Formation of the Pyridine Ring in the Synthesis of Dipyrido[3′,2′:4,5]thieno[3,2‐b:3,2‐d]pyridines.
Authors: Vasilin V. K. , Lipunov M. M. , Konyushkin L. D. , Kaigorodova E. A. , Krapivin G. D. 
Published: June 2007

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Rapid Access to Pyrimido[5,4‐c]isoquinolines via a Sulfur Monoxide Extrusion Reaction.
Authors: Fu Renzhong , Xu Xianxiu , Dang Qun , Chen Feng , Bai Xu 
Published: June 2007

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Regioselective Two‐Step Synthesis of 3‐Substituted 2‐Aminoimidazo[1,2‐a]pyrimidines.
Authors: Carballares Santiago , Cifuentes Marta M. , Stephenson Gregory A. 
Published: June 2007

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Electrophilic Aromatic Substitution Reactions of 1,2‐Dihydro‐1,2‐azaborines.
Authors: Pan Jun , Kampf Jeff W. , Ashe Arthur J. III 
Published: June 2007

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Convenient and Regioselective One‐Pot Solvent‐Free Synthesis of β‐Hydroxyphosphonates.
Authors: Sardarian A. R. , Shahsavari‐Fard Z. 
Published: June 2007

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
A Perylenedicarboxamide Linker for DNA Hairpins.
Authors: Lewis Frederick D. , Zhang Ligang , Kelley Richard F. , McCamant David , Wasielewski Michael R. 
Published: June 2007

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Naphthalenyl‐ and Anthracenyl‐Ethynyl dT Analogues as Base Discriminating Fluorescent Nucleosides and Intramolecular Energy Transfer Donors in Oligonucleotide Probes.
Authors: Xiao Qiang , Ranasinghe Rohan T. , Tang Adrian M. P. , Brown Tom 
Published: June 2007

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Furan Decorated Nucleoside Analogues as Fluorescent Probes: Synthesis, Photophysical Evaluation, and Site‐Specific Incorporation.
Authors: Greco Nicholas J. , Tor Yitzhak 
Published: June 2007

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Use of 2‐Aminopurine as a Fluorescent Tool for Characterizing Antibiotic Recognition of the Bacterial rRNA A‐Site.
Authors: Barbieri Christopher M. , Kaul Malvika , Pilch Daniel S. 
Published: June 2007

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Monitoring G‐Quadruplex Structures and G‐Quadruplex—Ligand Complex Using 2‐Aminopurine Modified Oligonucleotides.
Authors: Kimura Takumi , Kawai Kiyohiko , Fujitsuka Mamoru , Majima Tetsuro 
Published: June 2007

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Synthesis of Novel Polyhydroxylated Tetrahydropyranopyrroles.
Authors: Naud Sebastien , Pipelier Muriel , Chaumette Christophe , Viault Guillaume , Huet Francois , Legoupy Stephanie , Dubreuil Didier 
Published: June 2007

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Expedient Stereoselective Synthesis of Coronafacic Acid Through Intramolecular Diels—Alder Cyclization.
Authors: Moreau Benoit , Ginisty Maryon , Alberico Dino , Charette Andre B. 
Published: June 2007

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Crystalline Oxyfluorinated Open‐Framework Compounds: Silicates, Metal Phosphates, Metal Fluorides and Metal‐Organic Frameworks (MOF)
Authors: Loiseau Thierry , Ferey Gerard 
Published: June 2007

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
1,3‐Aminoalcohols and Their Derivatives in Asymmetric Organic Synthesis
Authors: Lait Susan M. , Rankic Danica A. , Keay Brian A. 
Published: June 2007

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Phenylselenoethers as Precursors of Acyclic Free Radicals: Creating Tertiary and Quaternary Centers Using Free Radical Based Intermediates
Authors: Cardinal‐David Benoit , Brazeau Jean‐Francois , Katsoulis Ioannins A. , Guindon Yvan 
Published: June 2007

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
The Nanothreading of Polymers
Authors: Rusa C. C. , Rusa M. , Peet J. , Uyar T. , Fox J. , Hunt M. A. , Wang X. , Balik C. M. , Tonelli A. E. 
Published: June 2007

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Cooperative Grid Vortals
Authors: Haupt Tomasz , Kalyanasundaram Anand 
Published: June 2007

AbstractVertical Grid portals, or Vortals, proved to be useful by providing access to applications running on high‐performance computational platforms and to distributed data enabling data sharing and other forms of collaboration. This paper identifies the commonalities between Vortals in various application domains, i.e. application‐independent patterns of orchestrating Grid services employed by a typical Vortal. These patterns can be captured as façades—a software layer between the Vortal business logic and generic Grid services that promotes a horizontal integration. The façades are reusable and considerably simplify the development of new Vortals. Furthermore, the façades foster interactions between different Vortals, and hence making them the cooperative Grid Vortals. Copyright © 2007 John Wiley & Sons, Ltd.
Crystallization behaviors of carbon fiber reinforced BN‐Si3N4 matrix composite
Authors: Li Bin , Zhang Chang‐Rui , Wang Si‐Qing , Cao Feng 
Published: June 2007

AbstractThe crystallization behaviors of a new carbon fiber reinforced composite with a hybrid matrix comprising BN and Si3N4 prepared by precursor infiltration and pyrolysis were investigated by Fourier transform infrared spectroscopy, X‐ray diffraction and scanning electron microscopy. The results show that the as‐received composite is almost amorphous, and its main composition is BN and Si3N4. When heat treated at 1600°C, the composite is crystallized and shows a much better crystal form. When heat treated at 2100°C, Si3N4 in the matrix is decomposed, and BN exhibits a relatively complete crystallization. The existence of B4C and SiC is detected, which indicates the interfacial chemical reactions between nitride matrices and carbon fibers. The surface morphology of carbon fibers in the composite changed significantly when heated from 1600 to 2100°C, which also proved the occurrence of interfacial chemical reactions. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Effect of crystal thickness of separate confinement heterostructure layers on 1.55‐μm loss‐coupled dfb laser characteristics
Authors: Han Jae‐Ho , Park Sung‐Woong 
Published: June 2007

AbstractWe investigated the effect of the crystal thickness of the separate confinement heterostructure (SCH) guiding layers on the characteristics (threshold current, quantum efficiency) of 1550‐nm loss‐coupled Distributed Feedback laser diode fabricated with a simple step growth having an automatically buried absorptive grating InAsP layer. By increasing the thickness of SCH crystal layers from 40‐nm to 80‐nm in both below and above the multi‐quantum well region, we could achieve lower threshold currents both in 25°C and 85°C with increased ratio of quantum efficiencies between two temperatures. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Luminescence of GaN single crystals prepared by heating a Ga melt in Na–N2 atmosphere
Authors: Yamada Takahiro , Yamane Hisanori , Goto Takenari , Yao Takafumi , Yao Yongzhao , Sekiguchi Takashi 
Published: June 2007

AbstractColorless transparent prismatic crystals (0.5‐2.0 mm long) and hopper crystals (1.0‐2.5 mm long) of GaN were prepared by heating a Ga melt at 800°C in Na vapor under N2 pressures of 7.0 MPa for 300 h. The photoluminescence (PL) spectrum of a prismatic crystal at 4 K showed the emission peaks of neutral donor‐bound exciton (D0‐X) and free exciton (XA) at 3.472 eV and 3.478 eV, respectively, in the near band edge region. The full‐width at half‐maximum (FWHM) of (D0‐X) peak was 1.9 meV. The emission peaks of a donor–acceptor pair transition (D0‐A0) and its phonon replicas were observed in a lower energy range (2.9‐3.3 eV). The emission peaks of the D0‐A0 and phonon replicas were also observed in the cathodoluminescence (CL) spectrum at 20 K. The (D0‐X) PL peak of a hopper crystal at 4 K was at 3.474 eV (2.1 meV higher), having a FWHM of 6.1 meV which was over 3 times larger than that of the prismatic crystal. A strong broad band with a maximum intensity around 1.96 eV was observed for the hopper crystals in the CL spectrum at room temperature. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Self‐Consistent Chemical Model of Partially Ionized Hydrogen Plasmas: Electrical Conductivity
Authors: Arkhipov Yu. V. , Baimbetov F. B. , Davletov A. E. 
Published: June 2007

AbstractThe Bogolyubov hierarchy for equilibrium distribution functions is employed to define a chemical model for partially ionized hydrogen plasmas. The Helmholtz free energy is found in a self‐consistent manner beyond the linear mixing rule allowing one to determine not only the ionization equilibrium but the correlation functions as well. Particle interactions are effectively treated such that the charged and neutral components of the plasma are closely interrelated which results in short‐range order formation in the system of interest. The method proposed is an analog of the Debye‐Hückel theory of fully ionized gases and allows one to study both thermodynamics and transport phenomena in a partially ionized hydrogen. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Properties of Hot Dense Plasmas by Orbital‐Free Molecular Dynamics
Authors: Lambert F. , Clérouin J. , Mazevet S. , Gilles D. 
Published: June 2007

AbstractQuantum Molecular Dynamics simulations (QMD) based on Density Functional Theory (DFT) are now the tool of choice for describing the properties of matter in the warm dense regime (WDM). Thermodynamic and transport properties can be computed for pure phases and mixtures for a wide range of densities ρ0/10 < ρ < 2 – 5ρ0 (where ρ0 is the normal material density) and temperatures 0 < T < 10 eV. The existence of upper bounds in density and temperature is mainly due to the introduction of orbitals for evaluating the electron kinetic energy in the Kohn‐Sham equations. To get rid of this time consuming part of the computation, we propose a model combining, in a consistent way an Orbital Free Density Functional approach based on the Thomas‐Fermi approximation of the electron kinetic energy coupled with classical Molecular Dynamics for the ions (referred as OFMD model).Thanks to an efficient numerical scheme, up to thousand of particles can be propagated leading to accurate static and dynamical properties. Simulations on iron up to 5 keV and boron up to 10 times the normal density were performed. A comparison with linear screening theories using Yukawa's potentials was also done. This method bridges the gap between quantum and classical molecular dynamics in the field of hot‐dense plasmas. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Localization of Coherent Wave Packets in Plasmas due to Decoherence
Authors: Gocke C. , Röpke G. 
Published: June 2007

AbstractLocalization of electron and ion states in a plasma is considered, applying the picture of a test particle in a dissipative environment. The plasma environment is represented by the dielectric function. For the reduced statistical operator a quantum master equation in Born‐Markov‐approximation can be used to quantify the influence of the dissipative background, which gives rise to decoherence and friction. We compare localization of ions due to collisional decoherence with the electronic part with screened interaction and localization by the thermal radiation field. The usual procedure to treat ions classically and electrons as quantum objects is supported by comparing the width of robust states and the mean distance in plasmas. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Hydrogen Balmer Spectrum from a High‐Pressure Arc Discharge: Revisited
Authors: Omar B. , Wierling A. , Günter S. , Röpke G. 
Published: June 2007

AbstractThe interpretation of hydrogen Balmer spectra emitted from a high‐pressure arc discharge (Radtke and Günther, Contrib. Plasma Phys. 26, 143 (1986)) is re‐examined. Assuming local thermodynamic equilibrium, synthetic Balmer spectra are calculated for given temperature and density conditions. Radiation transport is accounted for using a one‐dimensional plasma layer model. The lineshape of bound‐bound transitions is determined using a microscopic quantum‐statistical approach. Free‐free and free‐bound contributions are added by taking expressions from literature. Comparing the synthetic spectra with experimental ones, plasma temperature and density conditions are inferred. The plasma parameters are confronted with theoretical results for the compositions of dense plasma. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Properties of Dense Fluid Hydrogen and Helium in Giant Gas Planets
Authors: Vorberger J. , Tamblyn I. , Bonev St. A. , Militzer B. 
Published: June 2007

AbstractEquilibrium properties of hydrogen‐helium mixtures under thermodynamic conditions found in the interior of giant gas planets are studied by means of density functional theory molecular dynamics simulations. Special emphasis is placed on the molecular‐to‐atomic transition in the fluid phase of hydrogen in the presence of helium. Helium has a substantial influence on the stability of hydrogen molecules. The molecular bond is strengthened and its length is shortened as a result of the increased localization of the electron charge around the helium atoms, which leads to more stable hydrogen molecules compared to pure hydrogen for the same thermodynamic conditions. The ab initio treatment of the mixture enables us to investigate the structure of the liquid and to discuss hydrogen‐hydrogen, helium‐helium, and hydrogen‐helium correlations on the basis of pair correlation functions. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Super‐orthogonal space–time trellis codes for two transmit antennas in fast fading channels
Authors: Birol Aslı , Aygölü Ümit 
Published: June 2007

AbstractSuper‐orthogonal space–time trellis codes (SOSTTC) are full rate, full diversity space–time codes with high coding gains for quasi‐static fading channels. In this paper, this design approach is extended to fast fading channels and new SOSTTC are proposed for BPSK and QPSK modulations based on the design criteria valid for this type of channels. The new full rate codes have 4‐ and 16‐state trellises for BPSK and QPSK cases, respectively, to avoid parallel transitions which restrict the error performance. The frame error performances are evaluated through computer simulations and it is shown that the proposed codes have superior performance in the fast fading case compared to their counterparts previously given in the literature for fast and quasi‐static fading channels. Copyright © 2007 John Wiley & Sons, Ltd.
Glutamine synthetase is essential in early mouse embryogenesis
Authors: He Youji , Hakvoort Theodorus B.M. , Vermeulen Jacqueline L.M. , Lamers Wouter H. , Van Roon Maria A. 
Published: June 2007

AbstractGlutamine synthetase (GS) is expressed in a tissue‐specific and developmentally controlled manner, and functions to remove ammonia or glutamate. Furthermore, it is the only enzyme that can synthesize glutamine de novo. Since congenital deficiency of GS has not been reported, we investigated its role in early development. Because GS is expressed in embryonic stem (ES) cells, we generated a null mutant by replacing one GS allele in‐frame with a β‐galactosidase‐neomycine fusion gene. GS+/LacZ mice have no phenotype, but GSLacZ/LacZ mice die at ED3.5, demonstrating GS is essential in early embryogenesis. Although cells from ED2.5 GSLacZ/LacZ embryos and GSGFP/LacZ ES cells survive in vitro in glutamine‐containing medium, these GS‐deficient cells show a reduced fitness in chimera analysis and fail to survive in tetraploid‐complementation assays. The survival of heavily (>90%) chimeric mice up to at least ED16.5 indicates that GS deficiency does not entail cell‐autonomous effects and that, after implantation, GS activity is not essential until at least the fetal period. We hypothesize that GS‐deficient embryos die when they move from the uterine tube to the harsher uterine environment, where the embryo has to catabolize amino acids to generate energy and, hence, has to detoxify ammonia, which requires GS activity. Developmental Dynamics 236:1865–1875, 2007. © 2007 Wiley‐Liss, Inc.
Pressure segregation methods based on a discrete pressure Poisson equation. An algebraic approach
Authors: Badia Santiago , Codina Ramon 
Published: June 2007

AbstractIn this paper, we introduce some pressure segregation methods obtained from a non‐standard version of the discrete monolithic system, where the continuity equation has been replaced by a pressure Poisson equation obtained at the discrete level. In these methods it is the velocity instead of the pressure the extrapolated unknown. Moreover, predictor–corrector schemes are suggested, again motivated by the new monolithic system. Key implementation aspects are discussed, and a complete stability analysis is performed. We end with a set of numerical examples in order to compare these methods with classical pressure‐correction schemes. Copyright © 2007 John Wiley & Sons, Ltd.
Interrelations between motivational stance, cortical excitability, and the frontal electroencephalogram asymmetry of emotion: A transcranial magnetic stimulation study
Authors: Schutter Dennis J.L.G. , de Weijer Antoin D. , Meuwese Julia D.I. , Morgan Barak , van Honk Jack 
Published: June 2007

AbstractSeveral electrophysiological studies have provided evidence for the frontal asymmetry of emotion. In this model the motivation to approach is lateralized to the left, whereas the motivation to avoidance is lateralized to the right hemisphere. The aim of the present experiment was to seek evidence for this model by relating electrophysiological and phenomenological indices of frontal asymmetry to a direct measure of cortical excitability. Frontal asymmetrical resting states of the electroencephalogram and motivational tendencies indexed by the Carver and White questionnaire were compared with neural excitability of the left and right primary motor cortex as assessed by transcranial magnetic stimulation in 24 young healthy right‐handed volunteers. In agreement with the model of frontal asymmetry, predominant left over right frontal cortical excitability was associated with enhanced emotional approach relative to emotional avoidance. Moreover, the asymmetries of brain excitability and approach–avoidance motivational predispositions were both reflected by frontal beta (13–30 Hz) electroencephalogram asymmetries. In conclusion, the currently demonstrated interconnections between cortical excitability, electrophysiological activity, and self‐reported emotional tendencies for approach or avoidance support the frontal asymmetry of emotion model and provide novel insights into its biological underpinnings. Hum Brain Mapp 2008. © 2007 Wiley‐Liss, Inc.
Modulation of cortical oscillatory activity during transcranial magnetic stimulation
Authors: Brignani Debora , Manganotti Paolo , Rossini Paolo M. , Miniussi Carlo 
Published: June 2007

AbstractTranscranial magnetic stimulation (TMS) can transiently modulate cortical excitability, with a net effect depending on the stimulation frequency (≤1 Hz inhibition vs. ≥5 Hz facilitation, at least for the motor cortex). This possibility has generated interest in experiments aiming to improve deficits in clinical settings, as well as deficits in the cognitive domain. The aim of the present study was to investigate the on‐line effects of low frequency (1 Hz) TMS on the EEG oscillatory activity in the healthy human brain, focusing particularly on the outcome of these modulatory effects in relation to the duration of the TMS stimulation. To this end, we used the event‐related desynchronization/synchronization (ERD/ERS) approach to determine the patterns of oscillatory activity during two consecutive trains of sham and real TMS. Each train of stimulation was delivered to the left primary motor cortex (MI) of healthy subjects over a period of 10 min, while EEG rhythms were simultaneously recorded. Results indicated that TMS induced an increase in the power of brain rhythms that was related to the period of the stimulation, i.e. the synchronization of the α band increased with the duration of the stimulation, and this increase was inversely correlated with motor‐evoked potentials (MEPs) amplitude. In conclusion, low frequency TMS over primary motor cortex induces a synchronization of the background oscillatory activity on the stimulated region. This induced modulation in brain oscillations seems to increase coherently with the duration of stimulation, suggesting that TMS effects may involve short‐term modification of the neural circuitry sustaining MEPs characteristics. Hum Brain Mapp 2008. © 2007 Wiley‐Liss, Inc.