bluuebunny/crossref_metadata_2025 huggingface dataset:
Synthesis of Substituted Butenolides by the Ring Closing Metathesis of Two Electron Deficient Olefins: A General Route to the Natural Products of Paraconic Acids Class.
Authors: Selvakumar N. , Kumar P. Kalyan , Reddy K. Chandra Shekar , Chary B. Chandra
Published: June 2007

ChemInform 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.
Direct Synthesis of Pyrroles from Imines, Alkynes, and Acid Chlorides: An Isocyanide‐Mediated Reaction.
Authors: St. Cyr Daniel J. , Martin Nicolas , Arndtsen Bruce A.
Published: June 2007

ChemInform 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.
Mild Conditions for the Synthesis of Functionalized Pyrrolidines via Pd‐Catalyzed Carboamination Reactions.
Authors: Bertrand Myra Beaudoin , Leathen Matthew L. , Wolfe John P.
Published: June 2007

ChemInform 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 a Novel Dispiroheterocyclic Framework via the Regioselective 1,3‐Dipolar Cycloaddition Reaction of Azomethine Ylides.
Authors: Babu A. R. Suresh , Raghunathan R.
Published: June 2007

ChemInform 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.
Expeditious Synthesis of 3‐Arylidenelactams and 3‐Arylidenelactones from N‐Tosylaziridine Derivatives.
Authors: Lee Ka Young , Lee Hyun Seung , Kim Jae Nyoung
Published: June 2007

ChemInform 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.
Effect of Substitution on the Intramolecular 1,3‐Dipolar Cycloaddition of Alkene Tethered Muenchnones.
Authors: Belanger Guillaume , April Myriam , Dauphin Etienne , Roy Stephanie
Published: June 2007

ChemInform 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 Rapid and Efficient Synthesis of Benzimidazoles Using Hypervalent Iodine as Oxidant.
Authors: Du Li‐Hua , Wang Yan‐Guang
Published: June 2007

ChemInform 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 3‐Aminomethyl‐2‐aryl‐8‐bromo‐6‐chlorochromones.
Authors: Wallen Erik A. A. , Dahlen Kristian , Groetli Morten , Luthman Kristina
Published: June 2007

ChemInform 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.
Cyanoethylation of Substituted 4‐Azafluorenes. Synthesis of Spiro‐[4‐azafluorene‐9‐cyclopentenes].
Authors: Mikhailova N. M. , Levov A. N. , Gozun S. V. , Timonina O. O. , Toze F. , Varlamov A. V.
Published: June 2007

ChemInform 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.
Three‐Component Condensation of Hetarylguanidines with Aldehydes (Ketones) and Dicarbonyl Compounds.
Authors: Potapov A. Yu. , Shikhaliev Kh. S. , Krylsky D. V. , Krisin M. Yu.
Published: June 2007

ChemInform 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.
Syntheses of New 1,2‐, 1,3‐, and 1,4‐Diazine Derivatives. Part 2. Hydrolysis and Alkylation of Diazinylphenylacetonitriles.
Authors: Wisterowicz K. , Foks H.
Published: June 2007

ChemInform 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 Functionally‐Substituted 2‐Phenyl(2‐furyl)‐1,3,4‐oxadiazine Hydrobromides from Benzoyl(2‐furoyl)hydrazines and 1,3‐Dibromopropyne.
Authors: Volkova K. A. , Elokhina V. N. , Nakhmanovich A. S. , Larina L. I. , Albanov A. I.
Published: June 2007

ChemInform 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.
Efficient Synthesis of Phosphono‐ and Phosphinoxidomethylated N‐Heterocycles under Solvent‐Free Microwave Conditions.
Authors: Prauda Ibolya , Greiner Istvan , Ludanyi Krisztina , Keglevich Gyoergy
Published: June 2007

ChemInform 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.
Novel Triterpenoids from Microtropis triflora with Antitumor Activities.
Authors: Wang Kui‐Wu , Zhang Hong , Pan Yuan‐Jiang
Published: June 2007

ChemInform 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.
Two New Secoiridoid Glycosides from Tripterospermum chinense
Authors: Zhu Kai‐Cheng , Ma Chun‐Hui , Ye Guan , Fan Ming‐Song , Huang Cheng‐Gang
Published: June 2007

ChemInform 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.
Stille/Diels—Alder Reaction Sequences: Diversity‐Oriented Access to Novel Steroids.
Authors: Suennemann Hans Wolf , Hofmeister Anja , Magull Joerg , Banwell Martin G. , de Meijere Armin
Published: June 2007

ChemInform 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.
Simple and Convenient Synthesis of 21‐Thioalkylether Derivatives of Methyl 16‐Prednisolone Carboxylates.
Authors: Khan M. Omar F. , Lee Henry J.
Published: June 2007

ChemInform 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.
Oligodeoxyfluorosides: Strong Sequence Dependence of Fluorescence Emission.
Authors: Wilson James N. , Gao Jianmin , Kool Eric T.
Published: June 2007

ChemInform 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 and Fluorescence Properties of Dimethylaminonaphthalene—Deoxyuridine Conjugates as Polarity‐Sensitive Probes.
Authors: Okamoto Akimitsu , Tainaka Kazuki , Unzai Tomo , Saito Isao
Published: June 2007

ChemInform 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 Spectroscopy, Dynamics, and Electronic Structure of Pyrenyl—dU Nucleosides: P×+/dU×‐ Charge Transfer State Photophysics.
Authors: Netzel Thomas L.
Published: June 2007

ChemInform 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.
Triad Base Pairs Containing Fluorene Unit for Quencher‐Free SNP Typing.
Authors: Ryu Jin Ho , Seo Young Jun , Hwang Gil Tae , Lee Jin Yong , Kim Byeang Hyean
Published: June 2007

ChemInform 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 First Total Synthesis of Vinaxanthone, a Fungus Metabolite Possessing Multiple Bioactivities.
Authors: Tatsuta Kuniaki , Kasai Soko , Amano Yuki , Yamaguchi Takahiro , Seki Masashi , Hosokawa Seijiro
Published: June 2007

ChemInform 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.
Atromentin and Leucomelone, the First Inhibitors Specific to Enoyl‐ACP Reductase (FabK) of Streptococcus pneumoniae.
Authors: Zheng Chang‐Ji , Sohn Mi‐Jin , Kim Won‐Gon
Published: June 2007

ChemInform 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.
Latest Developments of Bulk Crystals and Thin Films of Rare‐Earth Doped CaF2 for Laser Applications
Authors: Doualan J. L. , Camy P. , Moncorge R. , Daran E. , Couchaud M. , Ferrand B.
Published: June 2007

ChemInform 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 σ‐CAM Mechanism: σ Complexes as the Basis of σ‐Bond Metathesis at Late‐Transition‐Metal Centers
Authors: Perutz Robin N. , Sabo‐Etienne Sylviane
Published: June 2007

ChemInform 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.
Recent Progress on Squaric Acid Research in Bioorganic Fields
Authors: Shinada Tetsuro , Isida Toshikazu , Ohfune Yasufumi
Published: June 2007

ChemInform 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.
Syntheses and Structural Studies of Functional Fullerenes
Authors: Matsuo Yutaka , Nakamura Eiichi
Published: June 2007

ChemInform 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.
Reformatsky Reactions Meet Catalysis and Stereoselectivity
Authors: Cozzi Pier Giorgio
Published: June 2007

ChemInform 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 Sonogashira Reaction: A Booming Methodology in Synthetic Organic Chemistry
Authors: Chinchilla Rafael , Najera Carmen
Published: June 2007

ChemInform 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.
Synthetic Studies on Breviones and Structurally Related Natural Products
Authors: Takikawa Hirosato
Published: June 2007

ChemInform 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.
Tether‐Directed Remote Functionalization of Fullerenes C60 and C70
Authors: Thilgen Carlo , Diederich Francois
Published: June 2007

ChemInform 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.
Reactivity Trends and Stereospecificity in Nucleophilic Substitution Reactions
Authors: Uggerud Einar
Published: June 2007

ChemInform 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.
Regio‐ and Stereoselectivity in the Paterno—Buchi Reaction on Furan Derivatives
Authors: D'Auria Maurizio , Emanuele Lucia , Racioppi Rocco
Published: June 2007

ChemInform 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.
Thioredoxin in Cancer — The Role of Histone Deacetylase Inhibitors
Authors: Marks Paul A.
Published: June 2007

ChemInform 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 Chemistry That Preceded Life′s Origin: A Study Guide from Meteorites
Authors: Pizzarello Sandra
Published: June 2007

ChemInform 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.
NMR Spectroscopy and Homogeneous Catalysis
Authors: Viviente Eloisa Martinez , Pregosin Paul S. , Schott Daniele
Published: June 2007

ChemInform 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.
Vapour growth and morphology of PbBr2 crystals
Authors: Kaito Takamasa , Yanagiya Shin‐Ichiro , Mori Atsushi , Inoue Tetsuo
Published: June 2007

In this paper, the vapour transport of PbBr2 under vacuum during vacuum distillation refining and its condensation on the wall of the vessel were described. The macro‐ and micro morphologies of PbBr2 crystals grown in the vessel (glass tube) were studied. The crystal shape changed dramatically depending on the positions of condensation in the vessel, i.e., the crystal shape varied from an isometric polyhedron to columnar crystals with facets, and to a massive crystal without facets with a rise in the wall temperature. These results were interpreted in terms of the concentration gradient of the molecules in the vessel, surface roughening and/or surface melting of the crystals. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Growth and crystal structure of the layered compound TlGaSe2
Authors: Delgado G. E. , Mora A. J. , Pérez F. V. , González J.
Published: June 2007

The semiconducting compound TlGaSe2 was grown by solid state reaction technique. The crystal structure of this material was confirmed by single‐crystal X‐ray diffraction. TlGaSe2 crystallizes in the monoclinic system with space group C2/c (No. 15), Z = 16 and unit cell parameters a = 10.779(2) Å, b = 10.776(1) Å, c = 15.663(5) Å, β = 99.993(6)°. The structural refinement converged to R(F) = 0.0719, R(F2) = 0.0652 and S = 1.17. The structure consists of a three‐dimensional arrangement of distorted TlSe8 and GaSe4 polyhedrons. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Growth of calcium oxalate crystals induced by complex films containing biomolecules
Authors: Xie Anjian , Shen Yuhua , Ma Dong , Huang Fangzhi , Qiu Lingguang , Li Shikuo , Chen Long
Published: June 2007

Nucleation and growth of calcium oxalate (CaC2O4) crystals induced by films composed of phosphatidylcholine (PC), cholesterol (CS) and human serum albumin (HSA), and of PC, CS and dextran have been carried out. The products obtained were characterized by Fourier transform infrared spectroscopy, scanning electron microscopy and ultraviolet‐visible spectroscopy. The results indicate that hexagonal calcium oxalate monohydrate (COM) and club‐shaped calcium oxalate trihydrate (COT) crystals are obtained on the PC/CH/HSA film, and the microstructure and properties of the PC/CH/HSA film depend on the weight ratio of PC to CS. With an increase in the PC‐to‐CS ratio, the number of COM crystals decreases gradually, and finally disappear, suggesting that PC inhibits the growth of COM crystals. On the PC/CS/dextran film, irregular COM and COT crystals are formed. The possible formation mechanisms of CaC2O4 on the two complex films are discussed. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Some peculiarities of Ti in‐diffusion in lithium niobate
Authors: Tsirlin M. , Dariel M.
Published: June 2007

The process of one‐ and two‐dimensional Ti in‐diffusion in lithium niobate, LiNbO3 (LN), single crystals of 〈x〉 and 〈z〉 orientations at 950‐1060°C in oxygen/water vapor medium had been studied. In the case of one‐dimensional diffusion, a flat diffusion front consisting of Ti solid solution in LN is formed. The process kinetics is described by Fick's equation for the case of a permanent source. In the case of two‐dimensional Ti diffusion, the diffusion zone contour acquires the shape close to elliptical. The diffusion rate in the tangential direction is about an order of magnitude higher than in the normal direction. A model qualitatively describing such nontrivial character of the diffusion process is suggested. The model is based on: a) incongruent lithium evaporation out of LN at high temperatures; b) low thermodynamic activity of Li in LiTiO3 – product of Ti interaction with LN. These factors produce a significant nonlinearity of the process, since a strong chemical bond between Li and Ti in this phase leads to a mutual increase in their diffusive mobility. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Synthesis and characterization of methylammonium tetrachlorocuprate (II) dihydrate crystals
Authors: Amirthaganesan G. , Kandhaswamy M. A. , Dhandapani M.
Published: June 2007

Single crystals of methylammonium tetrachlorocuprate (II) dihydrate were obtained by slow evaporation method at room temperature. The crystals were characterized through powder XRD, thermogravimetric (TG‐DTA), low temperature DSC studies and FTIR and far IR spectra. While the powder XRD confirms the crystallinity of the compound, the TG and DTA studies confirm the formation of the compound in the stoichiometric ratio and the presence of two water molecules of crystallization. The low temperature DSC study indicates a thermal anomaly at ‐3°C. The ordering of CH3NH3 group at low temperature causes phase transitions in the compound. The IR spectra characterize the various chemical bonding and water molecules in the compound. Laser Raman spectral studies under progress would help understand the mechanism of phase transitions at low temperatures. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Optical and electrical studies on spray deposited ZnO thin films
Authors: Sahay P. P. , Tewari S. , Nath R. K.
Published: June 2007

ZnO thin films were prepared by spray pyrolytic decomposition of zinc acetate onto a glass substrate. These films were analyzed for the optical and electrical properties. Optical studies show that in these films the electronic transition is of the direct transition type. The optical energy gap for the films of different thicknesses is estimated to be in the range 2.98 – 3.09 eV. Electrical studies indicate that the films exhibit thermally activated electronic conduction and the activation energies are found to be dependent on the film thickness. The complex impedance measurements were carried out over a wide range of frequencies at room temperature (300 K). All the impedance spectra contain only a single arc, but the arc has a non‐zero intersection with the real axis in the high frequency region. Also, the arc has its centre lying below with the real axis which indicates the multirelaxation behavior of the films. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Influence of Mg/Er co‐doping on the principal laser parameters of LiNbO3 crystals
Authors: Sun Liang , Yu Haitao , Lv Qiang , Guo Fengyun , Li Hongtao , Cai Wei , Xu Yuheng , Zhao Liancheng
Published: June 2007

Mg: Er: LiNbO3 crystals were grown by the Czochralski technique with various concentrations of MgO = 2 mol%, 4 mol%, 6 mol% and the fixed concentration of Er2O3= 1 mol% in the melt, and the 8 mol%Mg: 1 mol%Er: LiNbO3 crystal was fabricated by the Czochralski technique with special technology process. The crystals were treated by polarization, reduction and oxidation. The segregation coefficients of Mg2+ and Er3+ in Mg: Er: LiNbO3 crystals were measured by X‐ray fluorescence spectrograph, as well as the crystal's defect structure and optical properties were analyzed by the UV‐Vis, IR and fluorescent spectroscopy. The pump wavelength and the surge wavelength were determined. Using m‐line method tested optical damage resistance of those crystals, the results show that photodamage threshold of Mg: Er: LiNbO3 crystals are higher than that of Er: LiNbO3 crystal, and the oxidation treat could enhance the photodamage resistant ability of crystals while the reduction treat could depress the ability. The optical damage resistance of 8 mol%Mg: 1 mol%Er: LiNbO3 crystal was the strongest among the samples, which was two orders magnitude higher than that of 1 mol%Er: LiNbO3 crystal. The dependence of the optical properties on defect structure of Mg: Er: LiNbO3 crystals was discussed. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Thermodynamic Functions for Plasmas Beyond Montroll Ward
Authors: Kraeft W.‐D. , Vorberger J. , Gericke D. O. , Schlanges M.
Published: June 2007

We present an approach to the equation of state of fully ionized plasmas with any coupling strength. For this reason we go beyond the Montroll‐Ward contribution. The latter describes the thermodynamic functions at any degeneracy, but it only includes terms up to the order e4 with respect to the coupling strength. Therefore, we combine the Montroll‐Ward contribution and the corresponding exchange contribution up to the order e4 with classical hypernetted chain (HNC) calculations. The improvements made by the application of quantum pseudo‐potentials in the latter approach are discussed. Furthermore, a detailed analysis shows which terms must be omitted in the combined approach since they are included in both the Montroll‐Ward and the classical HNC contribution. Results for a hydrogen plasma are finally compared with simulation data and other theoretical results. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Effective Polarization Potential and Scattering Processes in a Partially Ionized Plasma
Authors: Ramazanov T. S. , Dzhumagulova K.N. , Omarbakiyeva Y.A. , Röpke G.
Published: June 2007

Elastic cross sections of electrons on atoms were investigated in the framework of a pseudopotential interaction model. Within a partial wave expansion, the scattering phase shifts are determined, and total and differential cross sections were obtained. The bremsstrahlung cross section for electron collisions with neutral atoms is evaluated. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Shell Structure of Yukawa Balls
Authors: Baumgartner H. , Kählert H. , Golobnychiy V. , Henning C. , Käding S. , Melzer A. , Bonitz M.
Published: June 2007

Spherical crystals continue to attract increasing interest in many fields, including trapped ions and dusty plasmas. These strongly coupled systems are excellent objects to study fundamental interactions and interesting correlation phenomena while they are relatively easy to realize and observe. Experiments and simulations show a spherical arrangement in nested shells. This work discusses new experimental and simulation results for small systems (N ≤ 54) as well as the influence of temperature and charge fluctuations on the shell populations. Finally, the cluster configurations are compared with an analytical shell model which is able to predict shell populations and energies for larger clusters. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Shift of Cl Kαand KβLines in Laser Produced Dense Plasmas
Authors: Sengebusch A. , Glenzer S. H. , Kritcher A. L. , Reinholz H. , Röpke G.
Published: June 2007

The features of chlorine K‐lines have been investigated to develop X‐ray probes for Compton scattering on warm dense plasmas. The shapes of these spectral lines have been studied at different laser energies by irradiation of thin saran foils by an intense ultra‐short‐pulse laser beam. The observed positions of Kαand Kβlines undergo a red shift due to a laser induced plasma environment. With increasing intensities the shift changes direction and turns into a blue shift caused by a higher contribution of K‐transitions occuring in further excited or ionized atoms. A theoretical approach based on the self‐consistent ion sphere model is outlined to describe this inversion. Plasma polarization effects are taken into account as well as different ionization stages of the X‐ray emitter within a warm dense plasma. Calculations using an improved ion sphere ansatz show good agreement with observations of the line shifts. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Hypernetted Chain Calculations for Two‐Component Plasmas
Authors: Schwarz V. , Bornath Th. , Kraeft W.‐D. , Glenzer S. H. , Höll A. , Redmer R.
Published: June 2007

We have performed HNC calculations for dense beryllium plasma as studied experimentally using x‐ray Thomson scattering, recently. We treated non‐equilibrium situations with different electron and ion temperatures which are relevant in pump‐probe experiments on ultra‐short time scales. To consider quantum effects adequately, we used effective pair potentials to describe the interactions. Results are compared with classical as well as quantum corrected Debye model calculations. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The Hall Effect in Dense Noble Gas Plasmas
Authors: Adams J. R. , Reinholz H. , Redmer R. , Shilkin N. S. , Mintsev V. B. , Gryaznov V. K.
Published: June 2007

In recent years, noble gas plasmas in magnetic fields have been investigated. Experimental results for the Hall coefficient have been made available. We compare these with results calculated using linear response theory in the Zubarev formalism. In this work, we investigate the possibility of using Hall voltage measurements to determine the electron concentration of partially ionized plasmas. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Crystallization in Mass‐Asymmetric Electron‐Hole Bilayers
Authors: Ludwig P. , Filinov A. , Lozovik Yu. E. , Stolz H. , Bonitz M.
Published: June 2007

We consider a mass‐asymmetric electron and hole bilayer. Electron and hole Coulomb correlations and electron and hole quantum effects are treated on first principles by path integral Monte Carlo methods. For a fixed layer separation we vary the mass ratio M of holes and electrons between 1 and 100 and analyze the structural changes in the system. While, for the chosen density, the electrons are in a nearly homogeneous state, the hole arrangement changes from homogeneous to localized, with increasing M, which is verified for both, mesoscopic bilayers in a parabolic trap and for a macroscopic system. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Determination of the Ion Temperature in a Plasma Created by Optical Field Ionization
Authors: Maynard G. , Lambert F. , Andreev N. , Robillar B. , Boudaa A. , Clerouin J. , Cros B. , Lenglet A. , Mocek T. , Sebban S.
Published: June 2007

The evolution with time of the ion temperature of a xenon gas during and after the irradiation with a high intensity laser beam is determined. The processes taken into account are (i) direct interaction with the laser beam, (ii) binary collisions with hot electrons, (iii) contribution with the electrostatic wakefield, (iv) hydrodynamic expansion and (v) transfer of potential to kinetic energy among the plasma ions. It is shown that, because the ions are strongly coupled, the last process is by far the most efficient one. Using the One Component Plasma (OCP) model, a simple analytical formula for the ion temperature at equilibrium is obtained. Application of this work to the development of soft x‐ray laser sources is stressed out. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Free‐Electron Generation in Laser‐Irradiated Dielectrics
Authors: Rethfeld B.
Published: June 2007

When transparent solids are irradiated with laser or particle beams an electron‐hole plasma may be generated, which consists of free electrons in the conduction band of the solid and holes in the valence band. If the electron density reaches values close to the critical plasma density (at which the plasma frequency of the free electron gas equals the laser frequency), the dielectric becomes highly absorbing. The large energy transfer to the solid leads to dielectric breakdown and further to phase transitions and ablation. We compare different models describing the temporal evolution of the free‐electron density under laser irradiation. The role of different ionization processes is investigated in dependence on laser pulse duration and intensity. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Transgenic mice expressing a dual, CRE‐inducible reporter for the analysis of axon guidance and synaptogenesis
Authors: Badaloni Aurora , Bonanomi Dario , Albieri Ilaria , Givogri Irene , Bongarzone Ernesto , Valtorta Flavia , Consalez G. Giacomo
Published: June 2007

Improved and modular tools are needed for the neuroanatomical dissection of CNS axonal tracts, and to study the cell‐intrinsic and cell‐extrinsic cues that govern their assembly and plasticity. Here we describe a general purpose transgenic tracer that can be used to visualize axonal tracts and synaptic terminals in any region of the embryonic neural tube or postnatal CNS, on any wild type or mutant genetic background. The construct permits CRE‐inducible expression of a dicistronic axonal marker encoding two surface reporter proteins: a farnesylated GFP and the human Placental Alkaline Phosphatase (PLAP). Both proteins localize alongside the neuronal surface, permitting the concomitant detection of cell body, neurites, and presynaptic and postsynaptic sites in the same neuron. This provides a CRE‐inducible dual system for imaging neural circuits in vivo, and to study their assembly and remodeling in cultured neurons, neural stem cells, and tissue explants derived from the reporter line. Unlike existing lines, this reporter does not encode a ubiquitously expressed, floxable LacZ gene, permitting the simultaneous analysis of beta galactosidase activity in mutant lines. genesis 45:405–412, 2007. © 2007 Wiley‐Liss, Inc.
Completeness, conservation and error in SPH for fluids
Authors: Vaughan G. L. , Healy T. R. , Bryan K. R. , Sneyd A. D. , Gorman R. M.
Published: June 2007

Smoothed particle hydrodynamics (SPH) is becoming increasingly common in the numerical simulation of complex fluid flows and an understanding of the errors is necessary. Recent advances have established techniques for ensuring completeness conditions (low‐order polynomials are interpolated exactly) are enforced when estimating property gradients, but the consequences on errors have not been investigated. Here, we present an expression for the error in an SPH estimate, accounting for completeness, an expression that applies to SPH generally. We revisit the derivation of the SPH equations for fluids, paying particular attention to the conservation principles. We find that a common method for enforcing completeness violates a property required of the kernel gradients, namely that gradients with respect the two position variables be equal and opposite. In such models this means conservation principles are not enforced and we present results that show this. As an aside we show the summation interpolant for density is a solution of, and may be used in the place of, the discretized, symmetrized continuity equation. Finally, we examine two examples of discretization errors, namely numerical boundary layers and the existence of crystallized states. Copyright © 2007 John Wiley & Sons, Ltd.
Simulation of transient gas flow at pipe‐to‐pipe intersections
Authors: Herty Michael , Seaïd Mohammed
Published: June 2007

We numerically investigate a well‐established mathematical model for gas flow in pipeline networks. The emphasis is given to the description of coupling conditions at pipe‐to‐pipe intersections. The accurate prediction of these coupling conditions is essential in order to achieve good performance and reliable numerical simulations of network simulations. Nowadays, a variety of theoretical results for a reduced geometry exists. We conduct a numerical simulation of the two‐dimensional representation at a pipe intersection. The results are used for verification and comparison with known theoretical results. High‐order and non‐oscillatory discretizations are used for solving the governing equations of gas flow. Verifications are conducted for two types of junctions to analyse the most adequate coupling conditions. Copyright © 2007 John Wiley & Sons, Ltd.
A simple high‐resolution advection scheme
Authors: Mingham C. G. , Causon D. M.
Published: June 2007

A simple, robust, mass‐conserving numerical scheme for solving the linear advection equation is described. The scheme can estimate peak solution values accurately even in regions where spatial gradients are high. Such situations present a severe challenge to classical numerical algorithms. Attention is restricted to the case of pure advection in one and two dimensions since this is where past numerical problems have arisen. The authors' scheme is of the Godunov type and is second‐order in space and time. The required cell interface fluxes are obtained by MUSCL interpolation and the exact solution of a degenerate Riemann problem. Second‐order accuracy in time is achieved via a Runge–Kutta predictor–corrector sequence. The scheme is explicit and expressed in finite volume form for ease of implementation on a boundary‐conforming grid. Benchmark test problems in one and two dimensions are used to illustrate the high‐spatial accuracy of the method and its applicability to non‐uniform grids. Copyright © 2007 John Wiley & Sons, Ltd.
Identifying technically efficient fishing vessels: a non‐empty, minimal subset approach
Authors: Flores‐Lagunes Alfonso , Horrace William C. , Schnier Kurt E.
Published: June 2007

Stochastic frontier models are often employed to estimate fishing vessel technical efficiency. Under certain assumptions, these models yield efficiency measures that are means of truncated normal distributions. We argue that these measures are flawed, and use the results of Horrace (2005) to estimate efficiency for 39 vessels in the Northeast Atlantic herring fleet, based on each vessel's probability of being efficient. We develop a subset selection technique to identify groups of efficient vessels at pre‐specified probability levels. When homogeneous production is assumed, inferential inconsistencies exist between our methods and the methods of ranking the means of the technical inefficiency distributions for each vessel. When production is allowed to be heterogeneous, these inconsistencies are mitigated. Copyright © 2007 John Wiley & Sons, Ltd.
Phylogenetic relationships of Danio within the order Cypriniformes: a framework for comparative and evolutionary studies of a model species
Authors: Mayden Richard L. , Tang Kevin L. , Conway Kevin W. , Freyhof Jörg , Chamberlain Sarah , Haskins Miranda , Schneider Leah , Sudkamp Mitchell , Wood Robert M. , Agnew Mary , Bufalino Angelo , Sulaiman Zohrah , Miya Masaki , Saitoh Kenji , He Shunping
Published: June 2007

The evolutionary relationships of species of Danio and the monophyly and phylogenetic placement of the genus within the family Cyprinidae and subfamily Rasborinae provide fundamentally important phyloinformatics necessary for direct evaluations of an array of pertinent questions in modern comparative biology. Although the genus Danio is not one of the most diverse within the family, Danio rerio is one of the most important model species in biology. Many investigations have used this species or presumed close relatives to address specific questions that have lasting impact on the hypothesis and theory of development in vertebrates. Largely lacking from this approach has been a holistic picture of the exact phylogenetic or evolutionary relationships of this species and its close relatives. One thing that has been learned over the previous century is that many organismal attributes (e.g., developmental pathways, ecologies, behaviors, speciation) are historically constrained and their origins and functions are best explained via a phylogenetic approach. Herein, we provide a molecular evaluation of the phylogenetic placement of the model species Danio rerio within the genus Danio and among hypothesized closely related species and genera. Our analysis is derived from data using two nuclear genes (RAG1, rhodopsin) and five mitochondrial genes (ND4, ND4L, ND5, COI, cyt b) evaluated using parsimony, maximum likelihood, and Bayesian analyses. The family Cyprinidae is resolved as monophyletic but the subfamily Rasborinae (priority over Danioinae) is an unnatural assemblage. Danio is identified as a monophyletic group sister to a clade inclusive of the genera Chela, Microrasbora, Devario, and Inlecypris, not Devario nor Esomus as hypothesized in previous studies. Danio rerio is sister to D. kyathit among the species of Danio evaluated in this analysis. Microrasbora and Rasbora are non‐monophyletic assemblages; however, Boraras is monophyletic. J. Exp. Zool. (Mol. Dev. Evol.) 308B:642–654, 2007. © 2007 Wiley‐Liss, Inc.
Temporal and spatial profiles of cell loss after spinal cord injury: Reduction by a metalloporphyrin
Authors: Ling Xiang , Liu Danxia
Published: June 2007

This study presents quantitative temporal and spatial profiles of neuronal loss and apoptosis following a contusion spinal cord injury (50 g · cm). The profiles were evaluated by counting the cresol violet–stained surviving cells and the total number of TUNEL‐positive cells and of TUNEL‐positive neurons in sections 0– 4 mm from the epicenter and 1, 6, 12, 24, 48, and 72 hr and 1 week postinjury. We demonstrated that neurons continue to disappear over 1 week postinjury and that neuronal loss shifts to areas longer distances from the epicenter over time. TUNEL‐positive cells in both gray and white matter appeared after 6 hr, gradually increased to a peak level after 48 hr, and declined by 72 hr postinjury. TUNEL‐positive neurons peaked earlier and were present for 1 week, although the total number of neurons was reduced significantly by the end of the week. The neuronal loss and apoptosis were partially prevented by a metalloporphyrin [Mn(III) tetrakis (4‐benzoic acid) porphyrin (MnTBAP)]. We demonstrated that MnTBAP (10 and 50 mg/kg, given intraperitoneally) significantly reduced neuronal death in the sections 1–2.5 mm rostral and 1 mm caudal from the epicenter compared with that in the vehicle‐treated group, suggesting MnTBAP is more effective in the sections rostral than in those caudal to the epicenter. MnTBAP (10 mg/kg) significantly reduced the number of TUNEL‐positive neurons in the sections 1 mm caudal from the epicenter. Our profiles provide a database for pharmacological intervention, and our results on MnTBAP treatment support an important role for antioxidant therapy in spinal cord injury. © 2007 Wiley‐Liss, Inc.
Signaling through C5aR is not involved in basal neurogenesis
Authors: Bogestål Yalda Rahpeymai , Barnum Scott R. , Smith Peter L.P. , Mattisson Victor , Pekny Milos , Pekna Marcela
Published: June 2007

The complement system, an important part of the innate immune system, provides protection against invading pathogens, in part through its proinflammatory activities. Although most complement proteins are synthesized locally in the brain and the relevant complement receptors are expressed on resident brain cells, little is known about brain‐specific role(s) of the complement system. C3a and C5a, complement‐derived peptides with anaphylatoxic properties, have been implicated in noninflammatory functions, such as tissue regeneration and neuroprotection. Recently, we have shown that signaling through C3a receptor (C3aR) is involved in the regulation of neurogenesis. In the present study, we assessed basal neurogenesis in mice lacking C5a receptor (C5aR–/–) and mice expressing C3a and C5a, respectively in the CNS under the control of glial fibrillary acidic protein (GFAP) promoter (C3a/GFAP and C5a/GFAP, respectively) and thus without the requirement for complement activation. We did not observe any difference among C5aR–/–, C3a/GFAP and C5a/GFAP mice and their respective controls in the number of newly formed neuroblasts and newly formed neurons in the subventricular zone (SVZ) of lateral ventricles and hippocampal dentate gyrus, the two neurogenic niches in the adult brain, or the olfactory bulb, the final destination of new neurons formed in the SVZ. Our results indicate that signaling through C5aR is not involved in basal neurogenesis in adult mice and that basal neurogenesis in adult C3a/GFAP and C5a/GFAP mice is not altered. © 2007 Wiley‐Liss, Inc.
Simultaneous Raman micro–spectroscopy of optically trapped and stacked cells
Authors: Jess P. R. T. , Garcés‐Chávez V. , Riches A. C. , Herrington C. S. , Dholakia K.
Published: June 2007

The combination of Raman spectroscopy and optical trapping holds great promise for single‐cell studies and is an emergent theme in microfluidic environments. Here, the evolution of the Raman signal intensity with an axial increment of the mass of the substance of interest inside a specific Raman excitation volume is investigated. Whilst Raman spectroscopy may be applied to tissue samples, solutions and single cells, there are no easily available methods to rapidly acquire signals from small cell populations. We show a simple but powerful method to record the Raman intensity signal simultaneously from a small number of trapped cells or colloidal particles using the technique of optical stacking. The Raman spectra of stacks of red blood cells and yeast cells show that this method can be applied to biological systems. We demonstrate how we may reveal biochemical fingerprints that would otherwise require long integration times for each single cell or averaging over many sequentially acquired cell spectra. There is potential to apply this method to directly attain Raman spectra from sorted sub‐populations of normal, abnormal and tumour cell lines. Copyright © 2007 John Wiley & Sons, Ltd.
Azoalkanes: A Novel Class of Additives for Cross‐Linking and Controlled Degradation of Polyolefins
Authors: Aubert Mélanie , Roth Michael , Pfaendner Rudolf , Wilén Carl‐Eric
Published: June 2007

A series of symmetrical and unsymmetrical azoalkanes were synthesized and their potential as a free‐radical source for rheology modification of polyolefins was investigated. The experimental results show that unsymmetrical azoalkanes, in particular N‐cyclohexyl‐N'‐tert‐octyldiazene (13), can be successfully used for manufacturing controlled‐rheology poly(propylene) and cross‐linked high‐density polyethylene. For example, the melt flow rate of a general‐purpose poly(propylene) (MFR = 14) could be increased to a value of 800 when 0.75 wt.‐% of azoalkane 13 was added during reactive processing. In parallel, it was found that 13 has a remarkable efficiency for free‐radical‐induced cross‐linking of high‐density polyethylene, resulting in similar gel contents to dicumyl peroxide.

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Effect of Sample Configuration on the Morphology of Foamed LDPE/PP Blends Injection Molded by a Gas Counterpressure Process
Authors: Kotzev Georgi , Djoumaliisky Strashimir , Krasteva Manya , Iliev Mario , Pérez Ernesto , Cerrada Maria Luisa
Published: June 2007

Blends of isotactic poly(propylene) and low‐density polyethylene with different composition ratios were prepared through direct melt compounding on a twin‐screw extruder. The specimens with various geometric configurations were injection‐molded using a gas counterpressure process, using blends to which 0.5 wt.‐% of a blowing agent was added. The influence of blend composition and specimen geometry on the structure and morphology of the samples was investigated by SEM and WAXS. The thermal behavior of the blends was analyzed by DSC. It was found that the morphology of each region depended on the composition ratio and specimen geometry.

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Stable Aqueous Dispersion of PEGylated Nanoparticles by Polyelectrolyte Complex Formation
Authors: Paneva Dilyana , Mespouille Laetitia , Bougard François , Manolova Nevena , Degée Philippe , Rashkov Iliya , Dubois Philippe
Published: June 2007

Stable aqueous dispersions of nanoparticles were prepared by polyelectrolyte complex formation between well‐defined poly(ethylene glycol)‐block‐poly(2‐acrylamido‐2‐methyl‐1‐propane sodium sulfonate) and poly(ethylene glycol)‐block‐poly[2‐(dimethylamino)ethyl methacrylate] diblock copolymers. Controlled synthesis of the copolymers was achieved by water‐based atom transfer radical polymerization (ATRP). The nanoparticles were characterized by a quite narrow and monomodal size distribution as evidenced by dynamic light scattering (DLS) and confirmed by atomic force microscopy (AFM) after solution casting and freeze‐drying.

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The molecular biology and clinical features of amyloid neuropathy
Authors: Benson Merrill D. , Kincaid John C.
Published: June 2007

Neuropathy is often a major manifestation of systemic amyloidosis. It is most frequently seen in patients with hereditary transthyretin (TTR) amyloidosis, but is also present in 20% of patients with systemic immunoglobulin light chain (primary) amyloidosis. Familial amyloid polyneuropathy (FAP) is the most common form of inherited amyloidotic polyneuropathy, with clinical and electrophysiologic findings similar to neuropathies with differing etiologies (e.g., diabetes mellitus). Hereditary amyloidosis is an adult‐onset autosomal‐dominant disease with varying degrees of penetrance. It is caused by specific gene mutations, but demonstration that a patient has one such mutation does not confirm the diagnosis of amyloidosis. Diagnosis requires tissue biopsy with demonstration of amyloid deposits either by special histochemical stains or electron microscopy. Transthyretin amyloidosis is treated by liver transplantation, which eliminates the mutated transthyretin from the blood, but for some patients continued amyloid deposition can occur from wild‐type (normal) transthyretin. Presently, a study is ongoing to determine whether amyloid deposition can be inhibited by small organic molecules that are hypothesized to affect the fibril‐forming ability of transthyretin. Proposed gene therapy with antisense oligonucleotides (ASOs) to suppress hepatic transthyretin synthesis is effective in a transgenic mouse model but has not yet been tested in humans. Muscle Nerve, 2007
Central activation, muscle performance, and physical function in men infected with human immunodeficiency virus
Authors: Scott Wayne B. , Oursler Krisann K. , Katzel Leslie I. , Ryan Alice S. , Russ David W.
Published: June 2007

Loss of muscle mass and limitations in activity have been reported in persons infected with human immunodeficiency virus (HIV), even those who are otherwise asymptomatic. The extent to which factors other than muscle atrophy impair muscle performance has not been addressed in depth. The purpose of this study was to determine the extent of neuromuscular activation of the knee extensors and ankle dorsiflexors of 27 men infected with HIV receiving antiretroviral therapy and its relationship to muscle performance. The central activation ratio (CAR) was determined using superimposed electrical stimulation during maximum voluntary contractions. In addition to force and power measurements, muscle cross‐sectional area and composition was evaluated using computed tomography. Aerobic capacity was determined from treadmill exercise testing. Eleven of the subjects had an impaired ability to activate the knee extensors (CAR = 0.72 ± 0.12) that was associated with weakness and decreased specific force. The reduced central activation was not associated with muscle area, body composition, aerobic capacity, CD4 count, or medication regimen. Those individuals with low central activation had higher HIV‐1 viral loads and were more likely to have a history of AIDS‐defining illness. These results suggest the possibility of a different mechanism contributing to muscle impairment in the current treatment era that is associated with impairment of central motor function rather than atrophy. Further investigation is warranted in a larger, more diverse population before more definitive claims are made. Muscle Nerve, 2007