bluuebunny/crossref_metadata_2025 huggingface dataset:
The Synthesis of Difluoro and Dimethyl Derivatives of 2,6-Bis(dicyanomethylene)-2,6-dihydro-4H-cyclopenta[2,1-b:3,4-b′]dithiophen-4-one (CPDT-TCNQ) and the Conducting Properties of the Metallic Salts Based on the Dimethyl Derivative
Authors: Chonan Takehiro , Takahashi Kazuko
Published: August 2004

In order to investigate how the sheet-like network along the side-by-side direction constructed by the strong inter-column S···N and O···H atom–atom contacts influences the stability of the metallic state of novel one-dimensional metallic anion radical salts of 2,6-bis(dicyanomethylene)-2,6-dihydro-4H-cyclopenta[2,1-b:3,4-b′]dithiophen-4-one (CPDT-TCNQ), the 3,5-difluoro (F2CPDT-TCNQ) and 3,5-dimethyl (Me2CPDT-TCNQ) derivatives of CPDT-TCNQ, not possessing hydrogen atoms at the 3,5-positions to construct the inter-column O···H contacts, have been synthesized. The anion radical salts, Me4X(Me2CPDT-TCNQ)2 (X = P and As), showed a metallic temperature dependence of the resistivity from room temperature down to around 240 K and 200 K, respectively, whereas Me4X(Me2CPDT-TCNQ)2 (X = N and Sb) were semiconducting. The metal–insulator transition temperatures (TMI) of Me4X(Me2CPDT-TCNQ)2 (X = P and As) are significantly higher than those of MX4(CPDT-TCNQ)2 (X = P and As). Moreover, the extent of destabilization of the metallic state is much more significant in Me4N(Me2CPDT-TCNQ)2, since MeN4(CPDT-TCNQ)2 is metallic down to 130 K. Although electric conduction can not occur along the side-by-side direction in either salt of CPDT-TCNQ and Me2CPDT-TCNQ, these facts suggest that the two-dimensional sheet-like molecular network along the a-axis may contribute to stabilize the one-dimensional metallic states of the anion radical salts of CPDT-TCNQ.
Origin of the Endo/Exo Stereoselectivity and Syn/Anti Face-Selectivity in Diels–Alder Reactions, Determined by Transition State Energy Partitioning
Authors: Kiri Shingo , Odo Yuka , Omar Huda Izzat , Shimo Tetsuro , Somekawa Kenichi
Published: August 2004

The origins of stereo- and face-selective Diels–Alder reactions of 5-substituted 1,3-cyclopentadienes (CP) with some dienophiles were elucidated by means of semiempirical PM5, DFT(B3LYP), and ab initio RHF methods. The activation energies by the improved PM5 and B3LYP/6-31+G(d) methods were in good agreement with the experimental results. We partitioned the activation energy (ΔEact) into diene deformation (ΔEdf-dien) and dienophile deformation (ΔEdf-dphil), and the diene–dienophile interaction (Eint) energies, in addition to the new intrinsic reaction coordinate (IRC) energy (ΔEirc) partitioning. Such analysis revealed the major factors in the determining endo/exo and syn/anti selectivities of the reactions of 5-substituted CP. The syn-selectivity of the 5-F-CP is explained by the lower ΔEact (2–3 kcal/mol) caused by relatively smaller ΔEdf-dien, which leads to slighter repulsion between the reactants. This low activation energy is inferred to be caused by the better second orbital interaction or intramolecular orbital interactions between the diene π and fluoro-substituent n orbital moieties, as well as by better intermolecular π–π orbital interactions between the diene-π and dienenophile-π moieties. On the other hand, the anti-selectivity of the methyl substituted CP mainly appears from bigger Edf-dien in the syn-isomer. A novel economical method of IRC energy partitioning to the reactants, TS intermediates and products is also introduced in order to verify the energy balance of other calculation methods and other reactions.
A Novel Short-Step Synthesis of Functionalized 4-Hydroxy-2-quinolones Using a 1-Hydroxybenzotriazole Methodology
Authors: Zikou Lamprini , Athanasellis Giorgos , Detsi Anastasia , Zografos Alexandros , Mitsos Christos , Igglessi-Markopoulou Olga
Published: August 2004

A novel method for the synthesis of 3-substituted 4-hydroxy-1-methyl- and 1-phenyl-2-quinolones is presented. The compounds are produced in a one-step reaction in very good yields (51–76%). The major advantage of the methodology is the short time for the synthesis in contrast to previous methodologies requiring several steps and harsh conditions for the synthesis of quinolone derivatives.
The Photoinduced Hydrogen Atom Transfer and trans–cis Isomerization of the C=C Double Bond in 1-(1-Hydroxy-2-naphthyl)-3-(1-naphthyl)-2-propen-1-one and Related Compounds Studied Using Nanosecond Time-Resolved Infrared Spectroscopy
Authors: Kaneda Kaoru , Sato Shin , Hamaguchi Hiro-o , Arai Tatsuo
Published: August 2004

The mechanism and intermediates of photoinduced hydrogen atom transfer and photoisomerization in 1-(1-hydroxy-2-naphthyl)-3-(1-naphthyl)-2-propen-1-one (1) and 1-(1-methoxy-2-naphthyl)-3-(1-naphthyl)-2-propen-1-one (2) have been investigated using nanosecond time-resolved infrared spectroscopy. For compound 1, a bleach signal was observed at 1575 cm−1 just after the laser excitation and recovered within 2 ms. The transient absorption at 1500 cm−1 decayed with two components of 1 μs and 2 ms, which are due to the triplet state and the ground state tautomer, respectively. On the basis of these results, the potential energy surface of hydrogen atom transfer in compound 1 was deciphered. Upon laser excitation of compound 2, the transient absorption signals at 1528 cm−1 and 1392 cm−1 assigned to the triplet state were observed in addition to the bleach signals at 1664 cm−1 and 1600 cm−1. The bleach signal at 1600 cm−1 remained as a permanent bleaching after the fast recovery with the 1.2 μs time constant. This result indicates that compound 2 underwent trans-to-cis isomerization upon laser excitation. By utilizing the data obtained in stationary and transient IR spectroscopy, we have directly determined the quantum yield of trans-to-cis isomerization to be 0.23 ± 0.01 from the difference in the IR signals.
Lithium Acetate-Catalyzed Aldol Reaction between Aldehyde and Trimethylsilyl Enolate in Anhydrous or Water-Containing N,N-Dimethylformamide
Authors: Nakagawa Takashi , Fujisawa Hidehiko , Nagata Yuzo , Mukaiyama Teruaki
Published: August 2004

Lithium acetate (AcOLi)-catalyzed aldol reactions between trimethylsilyl enolates and aldehydes proceed smoothly in anhydrous DMF or pyridine to afford the corresponding aldols in good to high yields under weakly-basic conditions (Tables 1–5). This catalytic aldol reaction is performed smoothly also by using other metal carboxylates that are easily prepared in situ by treating carboxylic acids with lithium carbonate (Li2CO3) (Table 2, Scheme 5). In order to show the effect of mild and readily-available AcOLi catalyst, the aldol reaction in water-containing DMF was studied in detail. AcOLi and various metal carboxylates behaved as effective Lewis base catalysts in aldol reactions between trimethylsilyl enolate and aldehydes in DMF–H2O (50:1) (Tables 6, 7). One of the most characteristic points of the above reaction that took place in water-containing DMF is that the aldehydes having a free amide and a hydroxy or even a carboxyl group reacted smoothly and afforded the desired aldols 29–31 in moderate to high yields (Table 8, Entries 12–15). Trimethylsilyl enolates derived from carboxylic esters behaved similarly as excellent nucleophiles in the above reaction. This is the first example of Lewis base-catalyzed aldol reactions to afford the desired aldol adducts even when silyl enolates derived from carboxylic esters were used in a water-containing organic solvent.
Efficient Method for the Preparation of Inverted Alkyl Carboxylates and Phenyl Carboxylates via Oxidation–Reduction Condensation Using 2,6-Dimethyl-1,4-benzoquinone or Simple 1,4-Benzoquinone
Authors: Shintou Taichi , Fukumoto Kentaro , Mukaiyama Teruaki
Published: August 2004

Oxidation–reduction condensation using in situ formed alkoxydiphenylphosphines, 2,6-dimethy-1,4-benzoquinone, and carboxylic acids provides a useful method for the preparation of inverted tertiary alkyl carboxylates from the corresponding chiral tertiary alcohols under mild and neutral conditions. Similarly, it has afforded alkyl carboxylates successfully in good-to-high yields by the combined use of alkoxydiphenylphosphines having primary, secondary, or tertiary alkoxy groups, carboxylic acids, and simple 1,4-benzoquinone. When chiral secondary or tertiary alcohols are used, the corresponding inverted secondary or tertiary alkyl carboxylates are also obtained in good-to-high yields. In addition, a convenient method for the preparation of phenyl carboxylates in high yields has been established by utilizing oxidation–reduction condensation in toluene at 110 °C using phenoxydiphenylphosphines in situ-formed from phenols and chlorodiphenylphosphine, 2,6-dimethyl-1,4-benzoquinone, and carboxylic acids.
Transformation of Aldehydes into (E)-1-Alkenylsilanes and (E)-1-Alkenylboronic Esters with a Catalytic Amount of a Chromium Salt
Authors: Takai Kazuhiko , Kunisada Yuji , Tachibana Yukiko , Yamaji Nana , Nakatani Emi
Published: August 2004

(Diiodomethyl)trimethylsilane (Me3SiCHI2, 1) is produced by treatment of iodoform with manganese in the presence of Me3SiCl. Aldehydes are converted to (E)-1-trimethylsilyl-1-alkenes in a stereoselective manner with a geminal dichromium reagent generated from 1, manganese, Me3SiCl, and a catalytic amount of CrCl3[thf]3 in THF. Similarly, (E)-1-alkenylboronic esters are prepared stereoselectively in good to excellent yields by treatment of aldehydes with a geminal dichromium reagent derived from Cl2CHB(OR)2 [(OR)2 = OCMe2CMe2O] and LiI instead of 1.
Asymmetric Autocatalysis Initiated by Chiral Ephedrine Immobilized on Silica Gel in a Diisopropylzinc Addition to Pyrimidine-5-carbaldehyde
Authors: Sato Itaru , Shimizu Masako , Kawasaki Tsuneomi , Soai Kenso
Published: August 2004

5-Pyrimidyl alkanol with up to 97% ee was formed using chiral ephedrine immobilized on silica gel in the enantioselective addition of diisopropylzinc to pyrimidine-5-carbaldehyde in conjunction with asymmetric autocatalysis.
Syntheses of the Novel Acidic and Basic Ligands and Superlattice Formation from Gold Nanoparticles through Interparticle Acid–Base Interaction
Authors: Kanehara Masayuki , Oumi Yasunori , Sano Tsuneji , Teranishi Toshiharu
Published: August 2004

Novel acidic or basic aryl-alkyl disulfides having phenol, benzoic acid, benzenesulfonic acid, aniline, and benzylamine groups were synthesized as protective agents for gold (Au) nanoparticles. Monodisperse Au nanoparticles passivated by these ligands were prepared using a chemical reduction technique, and self-assembled into well-ordered hexagonal close-packed (hcp) 2D superlattices on the substrate. We also present, for the first time, the formation of an aggregated multilayer of Au nanoparticles at a water–organic solvent interface by mixing separately synthesized acidic and basic Au nanoparticles. This film was definitely different from those obtained by the LB method and the conventional self-assembly method through solvent evaporation.
Preparation of Aluminum-Containing Self-Standing Mesoporous Silica Films
Authors: Shimura Naoki , Ogawa Makoto
Published: August 2004

Siliceous and aluminum-containing self-standing mesoporous silica films with the thickness of ca. 50 μm were synthesized by the solvent evaporation method from tetramethoxysilane, aluminum chloride hexahydrate, and octadecyltrimethylammonium chloride. The films possessed highly ordered mesostructures and large surface areas (over ca. 700 m2 g−1). The mesostructures of the products were controlled by the chemical compositions (Si/surfactant); siliceous mesostructured materials with hexagonal (P6m) and cubic (Pm3n) phases were obtained when the molar Si/surfactant ratios were 9 and 8, respectively. The aluminum-containing films with the molar Si/Al ratios of 50, 20, and 10 were also synthesized.
The Induction of a Helical Conformation in Polysilanes with an Optically Active Terminal Group
Authors: Sanji Takanobu , Takase Katsuyuki , Sakurai Hideki
Published: August 2004

Polysilanes with an optically active terminal (+) or (−)-menthoxy group, prepared by the anionic polymerization of masked disilene, adopt a preferential helical-sense conformation in solution at low temperature and also in the solid state at room temperature. The dependence on the molecular weight of the helical induction is also discussed. In a good/poor mixed solvent system, the induction of a helical conformation in the polysilanes was observed when forming aggregates.
TICT Induced Fluorescence Color Change Actualized in an Organogel System
Authors: Iwashita Yuya , Sugiyasu Kazunori , Ikeda Masato , Fujita Norifumi , Shinkai Seiji
Published: August 2004

A dimethylaminobenzoate group (TICT probe) was conjugated with a cholesterol group to assess the microenvironmental effect of the gel fibrils by a fluorescence method. It was found that the solvent-dependent dual fluorescence mode characteristic of TICT molecules in the sol phase almost disappears in the gel phase and only the shorter-wavelength fluorescence arising from the coplanar conformation is observed.
Hydrothermal Synthesis of [Al]-SSZ-24 from [Al]-Beta Zeolite ([Al]-BEA) as Precursors
Authors: Maekawa Hiroyoshi , Kubota Yoshihiro , Sugi Yoshihiro
Published: August 2004

The direct synthesis of [Al]-SSZ-24, a one-dimensional (1-D), high-silica, large-pore zeolite, using [Al]-BEA as precursors by hydrothermal route is successful.
Cluster Core Expansion through Incorporation of Transition-metal Fragments or an Alkyne Molecule into an Incomplete Cubane-type Fe2RuS4 Cluster
Authors: Okazaki Masaaki , Sakuma Atsushi , Tobita Hiromi , Ogino Hiroshi
Published: August 2004

Treatment of CpS22Fe2S4 (CpS2 = 1,3-C5H3(SiMe3)2) with [CpRu(MeCN)3]+ in acetonitrile at room temperature led to the formation of an incomplete cubane-type cluster [(CpS2Fe)2(CpRu)S4]+ (1). Further treatment of 1 with [Cp′Ru(MeCN)3]+ (Cp′ = Cp, Cp*) produced [(CpS2Fe)2(CpRu)(Cp′Ru)S4]2+. Cluster 1 reacted with DMAD to give the 1:1 adduct through formation of three sulfur–carbon bonds.
An Easy Route for the Synthesis of Ordered Three-Dimensional Large-Pore Mesoporous Organosilicas with Im-3m Symmetry
Authors: Zhang Zhendong , Tian Bozhi , Yan Xiaoxia , Shen Shaodian , Liu Xiaoying , Chen Dehong , Zhu Guangshan , Zhao Dongyuan , Qiu Shilun
Published: August 2004

Ordered three-dimensional (3-D) Im-3m-type mesoporous organosilicas with large-pore sizes ( > 6 nm) have been prepared by an easy solvent evaporation method by using bridged silsesquioxane 1,2-bis(triethoxysilyl)ethane precursor and triblock copolymers as the structure-directing agents.
An Examination of the Gelation of Methacrylate Type Crosslinking Agents for the Preparation of Polymer Monolith with 3D Ordered Network Structures
Authors: Aoki Hiroshi , Kubo Takuya , Watabe Yoshiyuki , Tanaka Nobuo , Norisuye Tomohisa , Hosoya Ken , Shimbo Kuniaki
Published: August 2004

The gelation of dimethacrylate type crosslinking agents was studied from the perspective of formation of ordered three dimensional (3D) network structures. Dynamic light scattering (DLS) data showed that the gelation of hydrophilic crosslinking agents having OH groups such as glycerol dimethacrylate (GDMA) was enhanced through hydrogen bonding in a hydrophobic solvent system such as toluene, which afforded more ordered 3D structures.
Simple Metal Oxides as Efficient Heterogeneous Catalysts for Epoxidation of Alkenes by Molecular Oxygen
Authors: Liang Jun , Tang Qinghu , Meng Guanyu , Wu Hongli , Zhang Qinghong , Wang Ye
Published: August 2004

Magnetite iron oxide (Fe3O4) has been found to be an efficient heterogeneous catalyst for the epoxidation of alkenes by molecular oxygen in the absence of a sacrificial reductant among various transition metal oxides. The reaction probably proceeds via a radical mechanism.
Photooxygenation of Olefins, Phenol, and Sulfide Using Fullerodendrimer as Catalyst
Authors: Takaguchi Yutaka , Yanagimoto Yasushi , Fujima Shohoko , Tsuboi Sadao
Published: August 2004

Fullerodendrimer acts as a new catalyst that uses oxygen and light to generate singlet oxygen (1O2). The dendrimer facilitates various types of singlet oxygenation reactions including ene reaction, the Diels–Alder reaction, and oxidation of phenol and sulfide.
Rapid Separation of Palladium(II) from Platinum(IV) in Hydrochloric Acid Solution with Thiodiglycolamide
Authors: Narita Hirokazu , Tanaka Mikiya , Morisaku Kazuko , Abe Tsutomu
Published: August 2004

Solvent extraction of some platinum group metals (Pd(II), Pt(IV), Rh(III)) and base metals (Fe(III), Cu(II), Zn(II)) in hydrochloric acid solution with N,N′-dimethyl-N,N′-di-n-octylthiodiglycolamide (MOTDA) was investigated. The extraction percentage of Pd(II) with MOTDA was nearly 100%, while MOTDA hardly extracted any of the other metal ions. It is noteworthy that the extraction of Pd(II) was extremely fast compared with the conventional extraction reagent, di-n-hexyl sulfide.
A Mild, Efficient, and Inexpensive Protocol for the Selective Deprotection of TBDMS Ethers Using KHSO4
Authors: Arumugam Pandurangan , Karthikeyan Ganesan , Perumal Paramasivan T
Published: August 2004

Potassium hydrogensulfate in 30% aq. methanol deprotects a variety of tert-butyldimethylsilyl ethers at room temperature in excellent yields.
Pt-Catalyzed Regio- and Stereoselective Thienylthiolation of Alkynes
Authors: Hirai Takayoshi , Kuniyasu Hitoshi , Kambe Nobuaki
Published: August 2004

The Pt-catalyzed decarbonylative thienylthiolation of terminal alkynes by thienylthioesters took place regio- and stereoselectively under toluene reflux to give vinylsulfides with cis-thienyl group at β-carbon in moderate to good yields.
A Mild Reduction Route to PTFE Degradation at Low Temperature
Authors: Zou Guifu , Yu Dabin , Jiang Changlong , Xi Guangcheng , Qian Yitai , Zhang Houbo
Published: August 2004

Poly(tetrafluoroethylene) has been degradated by a benign method at low temperature. Metal K plays an important effect in this process. The mild and economical route may be applied to decompose other polymers with hard degradation.
Significant Effect of Molecular Structure on Surface Relief Grating Formation for Novel Azobenzene-Based Photochromic Amorphous Molecular Materials
Authors: Ueda Hiromichi , Tanino Takahiro , Ando Hiroyuki , Nakano Hideyuki , Shirota Yasuhiko
Published: August 2004

A significant effect of molecular structure on the formation of surface relief grating (SRG) was found for novel azobenzene-based photochromic amorphous molecular materials, N,N′-bis[4-(phenylazo)phenyl]-N,N′-diphenyl-p-phenylenediamine and N,N-bis[4-(phenylazo)phenyl]-N′,N′-diphenyl-p-phenylenediamine. The results provide helpful information about SRG formation.
Efficient Catalyst for Low Temperature Solid-Phase Imidization of Poly(amic acid)
Authors: Fukukawa Ken-ichi , Shibasaki Yuji , Ueda Mitsuru
Published: August 2004

Efficient base-catalysts for low temperature solid-phase imidization of poly(amic acid) (PAA) have been found. Thermal imidization of PAA proceeded smoothly in the presence of 1 wt % of strong bases such as 1,4-diazabicyclo[2.2.2]octane (DABCO) and 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) at 200 °C in a short time, and no residues of DBU remained in the polyimide film.
Bio-template Synthesis of Uniform CdSe Nanoparticles Using Cage-shaped Protein, Apoferritin
Authors: Yamashita Ichiro , Hayashi Junko , Hara Masahiko
Published: August 2004

CdSe nanoparticles were synthesized in the cavity of the cage-shaped protein, apoferritin, by designing the slow chemical reaction system of Cd2+ and Se2−. The cavity size of apoferritin molecules is around 7 nm and the diameter of synthesized CdSe nanoparticles is about 6 nm with small size dispersion. CdSe nanoparticles as prepared are multi-crystalline and can be made into a single crystal by the heat-treatment under nitrogen gas. This bio-template synthesis provides a new method to synthesize uniform CdSe nanoparticles.
Glucose Reduction Route Synthesis of Uniform Silver Nanowires in Large-scale
Authors: Wang Zhenghua , Chen Xiangying , Liu Jianwei , Zhang Meng , Qian Yitai
Published: August 2004

Silver nanowires with average diameters of ≈100 nm and lengths up to 800 μm were hydrothermally prepared in large scale by reducing silver nitrate with glucose in the presence of poly(vinyl alcohol) (PVA) at 160 °C. The reaction temperature, the initial concentrations of the reagents, and the kind of polymer have effects on the formation of silver nanowires. The possible formation mechanism of silver nanowires was proposed.
Selective Synthesis of Wurtzite CdSe Nanorods and Zinc Blend CdSe Nanoparticals through Solvothermal Routes
Authors: Liu Yong , Xu Yao , Li Jun-Ping , Zhang Bin , Wu Dong , Sun Yu-Han
Published: August 2004

By simply changing the reactants’ composition, highly crystallized wurtzite CdSe nanorods and zinc blend CdSe nanoparticles were separately fabricated through a convenient solvothermal route with the reaction of cadmium nitrate (Cd(NO3)2·4H2O), hydrazine hydrate (N2H4·H2O), and Se in ethylenediamine at 140 °C.
The Abundances of Fragment Ions Formed via Skeletal Rearrangements from 2,5-Disubstituted-1,3,4-Oxadiazoles and Their Theoretical Calculated Stabilities
Authors: Frański Rafał , Eitner Krystian , Schroeder Grzegorz , Szwajka Oles P.
Published: August 2004

Protonated molecules of 2,5-di-R1,R2-substituted-1,3,4-oxadiazoles lose isocyanic acid (loss of mass 43) via skeletal rearrangement. This was observed in low-energy CID mass spectra recorded by using electrospray ionisation (ESI). On electron ionisation- induced decomposition, these compounds also reveal complex skeletal rearrangement, consisting on N2 and CO elimination, leading to the formation of fluorene or indene type ions. It was found that abundances of fragment ions formed in these processes are in good agreement with their theoretically calculated stabilities. In the case of ESI use, the fragment ion abundances were calculated in relation to [M + H]+ ion abundances and for EI use, where extensive fragmentations proceed, the sums of the abundances of [M – N2 – CO]+• ions and abundances of fragment ions derived from them were expressed as a percentage of total-ion current.
Parameterizing Matrix-Assisted Laser Desorption/Ionization: Effect of Solvents and Co-Additives on Analyte Peak Intensities
Authors: Bashir S. , Mutter R. , Derrick P.J.
Published: August 2004

The peak intensities obtained when 2,5-dihydroxybenzoic acid (DHB) was used as a “classic” matrix were measured using substance P (SP) and betacyclodextrin (BCD) as analytes. Enhancements in peak intensities were observed going from 1:1 MeOH / H2O to dimethylforamide (DMF) as matrix solvents. Also non-covalent interactions between SP and solvent and DHB were observed suggesting close interactions between matrix, solvent and analyte in the gas phase. Peak enhancements were previously reported with “superDHB” (DHB and 2-hydroxy-5-methoxybenzoic acid at 10% v / v). Co-addition of structural analogs and their respective absorption coefficients were determined. It was found that other analogs used as co-matrices could give analyte peak enhancement similar to those reported for sDHB with the additional benefit that some analogs could act as matrices with DHB addition. No direct correlation was observed between absorption coefficient and the ability of the molecule to act as a “good” UV MALDI matrix.
Structural Reinvestigation of the Core Oligosaccharide of a Mutant Form of Aeromonas Salmonicida Lipopolysaccharide Containing an

O

-4 Phosphorylated and

O

-5 Substituted Kdo Reducing end Group Using Electrospray Quadrupole Time of Flight Tandem Mass Spectrometry
Authors: Banoub Joseph , Cohen Alejandro , Aneed Anas El , LeQuart Vincent , Martin Patrick
Published: August 2004

The molecular structure of the mutant form of the lipopolysaccharide (LPS) of Aeromonas salmonicida was determined to contain an O-4 phosphorylated and O-5 substituted Kdo reducing group, and is proposed as the following:

It was established that during the cleavage of this LPS with 1% acetic acid, to release the core oligosaccharide from the Lipid A portion, we obtained a degraded core oligosaccharide which eliminated its phosphate group with extreme ease. The precise molecular structure of this dephosphorylated core was deduced by electrospray mass spectrometry and is proposed as the following:

Low-energy collision electrospray ionization quadrupole quadrupole time-of-flight tandem mass spectrometry (ESI-QqToF-MS/MS) analysis of the dephosphorylated core oligosaccharide confirmed the presence of the O-5 glycosylated 4,8- and 4,7-anhydro derivatives of the enolizable α-keto-acids. The collision-induced dissociation (CID) tandem mass spectrometric analysis of the heterogeneous mixture of the permethylated core oligosaccharide established the unreported methylation reaction on the diastereomeric 4,8- and 4,7-anhydro α-keto-acids and the complete permethylation and addition reaction of the O-5 glycosylated open chain reducing end terminal D- arabino-3-en-2-ulonic acid. The stereo-specific fragmentation routes obtained during the tandem mass spectrometric analysis permitted the precise sequencing of this dephosphorylated rough core oligosaccharide of the mutant LPS of A. salmonicida.
Rearrangements of Transient Neutral Molecules in the Gas Phase. Does the Conversion of CCCHO to HCCCO Involve Oxygen or Hydrogen Migration?
Authors: Tran Khoa M. , McAnoy Andrew M. , Bowie John H.
Published: August 2004

Stable (CC13CHO)− may be formed in the chemical ionisation ion source of a VG ZAB 2HF mass spectrometer by the SN2(Si) reaction between Me3SiC≡C13CHO and F−. Vertical (Franck–Condon) one-electron oxidation of (CC13CHO)− in the first of the tandem collision cells of a VG ZAB 2HF mass spectrometer gives CC13CHO. Some of these neutrals have sufficient excess energy to effect rearrangement to HCC13CO, some of which are energised and decompose to HCC• and 13CO. Thus, the neutral rearrangement exclusively involves H migration: no products from O migration are detected. The corresponding two-electron oxidation of (CC13CHO)− gives mainly unrearranged (CC13CHO)+. A minority of these cations are energised and rearrange by H and O migration to yield (HCC13CO)+ and (OCC13CH)+, respectively. All experimental observations are backed up by molecular modelling at the CCSD(T)/aug-cc-pVDZ//B3LYP/6-31G(d) level of theory.
Low-Pressure Chemical Ionization in Ion Trap Mass Spectrometry
Authors: Bouchonnet Stéphane , Libong Danielle , Sablier Michel
Published: August 2004

This article presents the specificities of low-pressure chemical ionization in ion trap mass spectrometry. One main feature is the ability to perform chemical ionization with liquid reagents as readily as with “conventional” gases (methane, isobutane and ammonia). The reactivities and analytical applications of gas and liquid reagents are summarized from literature data and are compared when possible.
Derivatization in Mass Spectrometry—4. Formation of Cyclic Derivatives
Authors: Zaikin Vladimir G. , Halket John M.
Published: August 2004

This fourth in a series of reviews describes a further common derivatization approach, namely, the formation of cyclic derivatives (cyclic acetals and ketals, boronates, siliconides, carbonates and other miscellaneous derivatives) that can be used to increase volatility and to improve chromatographic and, if possible, the mass spectral properties of various di- and polyfunctional compounds. Some chemical aspects of this type of derivatization are briefly discussed. Characteristic mass spectral features of various cyclic derivatives that are helpful in the structure determination, profiling and quantitation of multifunctional organic compounds are presented. Some recent analytical applications of mass spectrometry, in conjunction with preliminary cyclic derivative formation, are given.
Collision-Induced Dissociation of a Series of Coumarins Studied by Positive- and Negative-Ion Electrospray Triple Quadrupole Tandem Mass Spectrometry
Authors: Lerman Lidija , Klonkay Andreja Čempuh , Filipović Anita , Elenkov Ivaylo
Published: August 2004

Aryl-substituted 4-hydroxycoumarins (1–57) were investigated by electrospray ionisation (ESI) mass spectrometry. Their fragmentation in the ion source or in the collision cell of a triple quadrupole mass spectrometer was investigated. The effect of the substituents in the aromatic ring on the fragmentation of the 4-hydroxycoumarin derivatives is shown. The influence of the tautomerism on the formation of quasimolecular ions and mass spectral fragmentation was explained. Mass spectral studies on some deuterated compounds proved some of the proposed fragmentation pathways. Results obtained are very useful in the process of detection and characterisation of 4-hydroxycoumarins, as well as for structural elucidation of their more complex derivatives.
Long-term results of gentamicin inner ear perfusion in Ménière’s disease
Authors: Suryanarayanan R. , Cook J.A.
Published: August 2004

Chemical perfusion of the inner ear is an increasingly popular treatment for Ménière’s disease. The authors report on the long-term results of 22 patients treated with gentamicin delivered via a round window micro-catheter. Patients with Ménière’s disease underwent continuous, low dose (10 mg/ml) gentamicin infusion at 5 microlitre per hour for 10 days, through a micro-catheter placed into the round window niche. Vertigo was controlled in 95 per cent, whilst preserving hearing in 77 per cent. Hearing improved in three patients. Three patients with pre-operative serviceable hearing (PTA < 50 db) demonstrated reduced hearing; two patients with pre-operative non-serviceable hearing developed a dead ear. Tinnitus and aural fullness remained unchanged or improved in 86 per cent and 68 per cent respectively. Long-term vertigo control can be achieved using low dose gentamicin, whilst preserving hearing and vestibular function in the majority of patients. This procedure appears to stabilize the vestibular function, enhancing the chance of effective vestibular rehabilitation.
Management of globus pharyngeus: review of 699 cases
Authors: Harar R.P.S. , Kumar S. , Saeed M.A. , Gatland D.J.
Published: August 2004

The principal reason for performing investigations in patients with globus pharyngeus is to detect a pharyngeal or upper oesophageal malignancy presenting this way. There is uncertainty regarding both the necessity for investigation in globus patients and the first line investigation of choice in the screening of such patients. The authors therefore undertook a retrospective study of 699 patients who presented with globus sensation. Of these, 451 patients (64.5 per cent) had a typical history and in these patients, outpatient examination, including fibre-optic nasendoscopy was able to detect all pathologies, except one insignificant pharyngeal pouch, which required no intervention and one patient with a distal peptic stricture. In patients with atypical symptoms the combination of fibre-optic nasendoscopy and barium swallow identified all pathologies (five aerodigestive tract malignancies) except one distal peptic stricture. The authors concluded that if out-patient examination is adequate, no further investigation of typical globus symptoms is required. Such a policy would produce significant savings for both out-patient and radiology services.
Use of magnetic resonance imaging as the primary imaging modality in the diagnosis and follow-up of malignant external otitis
Authors: Ismail H. , Hellier W.P. , Batty V.
Published: August 2004

Malignant external otitis (MEO) is a severe infection of the external auditory meatus caused by Pseudomonas aeruginosa. Classical features include unrelenting deep otalgia, otorrhoea and granulations in the floor of the ear canal. Treatment is generally protracted antibiotic therapy and monitoring of inflammatory markers; the erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP). Traditionally computed tomography (CT) has been the imaging modality of choice. The authors present a case where magnetic resonance imaging (MRI) has been crucial in the diagnosis and follow up of a patient with MEO.
Quality of life of well-differentiated thyroid carcinoma patients
Authors: Dagan Tal , Bedrin Lev , Horowitz Zeev , Chaushu Gavriel , Wolf Michael , Kronenberg Jona , Talmi Yoav P.
Published: August 2004

The thyroid gland is the second most common site for malignancy in the head and neck region. Quality of life (QOL) of thyroid cancer patients has not been studied directly. The QOL of long-term thyroid carcinoma patients was investigated. A standardized set of questions based on the University of Washington QOL questionnaire for head and neck cancer with specific domains associated with thyroid disease was created. This questionnaire was mailed to patients who underwent total thyroidectomy for well-differentiated cancer in the department of Otolaryngology-Head and Neck surgery at the Chaim Sheba Medical Centre in Israel between the years 1994–2000.

Seventy-eight patients undergoing total thyroidectomy were identified. Forty-eight patients were excluded and 20 out of the 30 remaining patients responded to the questionnaires. Six were male and 14 female, 12 were under the age of 45 (these 12 patients were staged as stage 1). Eleven patients underwent neck dissection. General health and QOL were significantly better for the younger age group and so was the calcium balance score. General health and QOL were significantly better for patients undergoing neck dissection. The overall QOL score was 3.8 conforming with ‘good’ in the questionnaire. Surgery and initial radioiodine treatment scored 6.75 and 6.9 respectively in the distressing scale (0–10 range: 10 = most distressing). The highest distress was encountered during withdrawal from thyroid hormone. Women rated the importance of proper replacement therapy significantly higher than men. Global low scores were found for employment and for effective L-thyroxine replacement therapy.

Overall, QOL in these patients was good although lower than expected when compared with other forms of cancer. Age and gender-related differences were noted. Better QOL in neck dissection patients is probably associated with age under 45 years. High distress scores for hormone withdrawal during periodical imaging correspond with former reports and supports use of Thyrogen®. Better hormone balance is warranted for this group.
Prostaglandins, leukotrienes and perennial rhinitis
Authors: Shahab Riad , Phillips David E. , Jones Andrew S.
Published: August 2004

Prostaglandins and leukotrienes are implicated in conditions of both the upper and lower airways. In the former they are deranged in nasal polyposis, intrinsic rhinitis and allergic rhinitis while in the latter they are involved in the pathogenesis of asthma. The aim of the present study was to measure mucosal eicosanoid levels in the three types of rhinitis and compare with controls. In addition, the effect of topical steroids on eicosanoid levels in rhinitis was examined.

The levels of prostaglandins E2 (PGE2) and D2 (PGD2) and of leukotrienes E4 (LTE4) and B4 (LTB4) were measured in nasal biopsies from the inferior turbinates of patients suffering from perennial rhinitis and a control group. Rhinitis patients were classified into three categories: perennial allergic rhinitis (PAR), non-allergic rhinitis with eosinophilia (NARES) and noneosinophilic non-allergic rhinitis (NENAR) on the basis of symptoms, secretion eosinophilia, nasal resistance and allergy testing. Patients with rhinitis were randomized into two groups. One received fluticasone propionate nasal spray (FPANS) and the other a placebo (PNS) over a period of six weeks prior to the biopsies.

One hundred and one patients with PAR, NARES or NENAR were recruited sequentially and the control group consisted of 21 patients with no evidence of rhinitis but with nasal obstruction due to septal deviation.

Untreated rhinitics had significantly lower levels of PGE2, PGD2 and LTE4 than non-rhinitic controls. Six-weeks’ treatment with FPANS significantly increased the levels of those eicosanoids in patients with PAR and NARES but they were still significantly below normal. Levels of LTB4 in all three rhinitis groups were not significantly different from controls and treatment with topical steroids had no effect. Their findings are contrary to current thinking that increased levels of eicosanoids, in particular cysteinyl-leukotrienes, play an important role in the pathogenesis of chronic, non-infective upper airway inflammation.
Anhidrotic ectodermal dysplasia presenting as atrophic rhinitis
Authors: Sachidananda Ravi , Nagadi Anita , Dass A.A. , Praveen Kmar B.Y.
Published: August 2004

Atrophic rhinitis is a chronic inflammatory disease of the nose. The aetiology of primary atrophic rhinitis is not yet known, although secondary atrophic rhinitis is known to be associated with chronic granulomatous diseases such as tuberculosis and leprosy. The authors report a case of atrophic rhinitis, which was a presenting feature of a rare genetic disorder known as Christ-Siemens-Touraine syndrome, also known as anhidrotic ectodermal dysplasia.
Neck dissection findings in primary head and neck high-grade adenocarcinoma
Authors: Sheahan Patrick , Byrne Miriam , Hafidh Maky , Toner Mary , Simon Conrad
Published: August 2004

Primary salivary adenocarcinoma of the head and neck is rare. In cases where cervical metastases are evident or suspected, neck dissection is likely to play a role in management. However, there is little data in the literature regarding the findings and outcome of neck dissection in these patients. The present study comprised a review of 12 patients with high-grade salivary adenocarcinoma (salivary ductal carcinoma or adenocarcinoma, not otherwise specified (NOS). Eight underwent neck dissection (four modified radical, four selective). Histological examination showed evidence of cervical metastases in five. The prevalence of occult metastases in the N0 neck was 40 per cent. Computed tomography (CT) and magnetic resonance imaging (MRI) were not useful in detecting occult neck disease. Five patients had no evidence of disease at the most recent follow up. Neck dissection is indicated in patients with high-grade salivary adenocarcinoma, and may provide information for planning adjuvant treatment.
How serious are oral infections?
Authors: Baqain Zaid H. , Newman Laurence , Hyde Nicholas
Published: August 2004

Life-threatening conditions following dental infections have been rare since antibiotics were introduced into the world of medicine. However, infections spreading through the soft tissues of the head and neck are encountered occasionally and mortality is still reported as a result of sepsis or airway embarrassment. A case of Ludwig’s angina from odontogenic infection that progressed into mediastinitis and pericarditis is presented. The steps adopted in the management of this case highlight the significance of early recognition and diagnosis of the source of deep cervical infections, the importance of securing the airway, effecting surgical drainage and aggressive intravenous antibiotic therapy.
Magnetic resonance imaging of cochlear modiolus: determination of mid-modiolar area and modiolar volume
Authors: Kendi Tuba Karagülle , Arikan Osman Kürsat , Koç Can
Published: August 2004

Modiolar deficiency has been reported as representing the mildest form of cochlear dysplasia. In this study the authors aimed to determine baseline values of the mid-modiolar area and modiolus volume in normal subjects. In this way they aimed to improve the detection of previously underdiagnosed subtle cochlear dysplasia in patients with sensorineural hearing loss.
Ototoxicity after use of neomycin eardrops is unrelated to A1555G point mutation in mitochondrial DNA
Authors: Yamasoba Tatsuya , Tsukuda Katsunori
Published: August 2004

Ear drops containing neomycin only rarely cause ototoxicity. The authors report on three patients with a tympanic membrane perforation who developed severe ototoxicity after use of eardrops containing 0.35 per cent neomycin. Mitochondrial DNA analysis revealed that there was no A1555G point mutation in these patients. This finding indicates that application of low concentration neomycin to the middle ear can cause severe inner ear damage even in humans who are not hyper-susceptible to aminoglycosides.
Spontaneous bilateral internal jugular vein thrombosis: a sign of metastasis
Authors: Cheang P.P. , Fryer J. , Ayoub O. , Singh V.
Published: August 2004

Head and neck swellings are common referrals to the otolaryngology department, with a wide range of aetiologies. Internal jugular vein thrombosis presenting as swelling in the neck is a rare occurrence. The authors report a case of bilateral internal jugular vein thrombosis secondary to malignant lymphadenopathy of unknown origin. The patient presented with a short history of a diffuse swelling in the neck with neck stiffness. Examination revealed palpable cervical and axillary lymphadenopathy. Causes of spontaneous internal jugular vein thrombosis were discussed.
Adduction arytenopexy for vocal fold paralysis: indications and technique
Authors: Zeitels Steven M. , Mauri Marcelo , Dailey Seth H.
Published: August 2004

Adduction arytenopexy was designed as an innovation to arytenoid adduction, however the pragmatic issues regarding patient selection for these procedures has not been comprehensively assessed.

A prospective examination was performed on 100 consecutive patients who had undergone laryngoplastic phonosurgical reconstruction for paralytic dysphonia. Seventy-seven of 100 (77 per cent) were judged pre-operatively to gain potentially significant phonatory enhancement from an arytenoid procedure. Fifty-six of 77 (73 per cent) underwent adduction arytenopexy; 17 of 77 (22 per cent) were judged pre-operatively to have inadequate respiratory abduction of the contralateral arytenoid and two out of 77 (three per cent) had athletic aerodynamic requirements. In another two out of 77 (three per cent), there was a chance of favourable reinnervation and thus it was not the preferred method.

The majority of patients were judged pre-operatively to gain potentially substantial phonatory enhancement from an arytenoid procedure. However, in this series, approximately 25 per cent of the patients were considered to be unsuitable candidates for an arytenoid medializing procedure, primarily because it was deemed that the operation could result in an inadequate airway.
Chondrosarcomas of the temporal bone: presentation and management
Authors: Raghu Mallappa , Moumoulidis Ioannis , De Ranit , Moffat David
Published: August 2004

Chondrosarcomas (CSA) of the temporal bone are rare primary malignant tumours that are slow growing, but locally aggressive. The management of CSAs involving the temporal bone is challenging and necessitates a multidisciplinary approach in a tertiary referral unit well practised in skull base surgery. Their management with particular reference to modes of presentation and treatment strategies has been reviewed here.
Descriptive study of the type and severity of decompensation caused by comorbidity in a population of patients with laryngeal squamous cancer
Authors: Paleri V. , Narayan R. , Wight R.G.
Published: August 2004

The aim of this study was to systematically identify the type and severity of all comorbid conditions in a cohort of 180 patients with laryngeal squamous cancer. The authors retrospectively surveyed the notes using the Adult Comorbidity Evaluation −27 index (ACE−27) and applying a systematic process of data abstraction that had previously been shown to be accurate and reliable. The results provided insight into the distribution, site and extent of decompensation caused by comorbidity. It was found that 116 (64.4 per cent) of 180 patients in the study population had some form of comorbid illness, with the cardiovascular and respiratory systems being the top two body systems affected in 43.9 per cent and 24.1 per cent respectively. One-quarter (25.8 per cent) of these 116 patients had comorbid illnesses in more than one body system. Concurrent neurological disease is associated with high mortality. The ACE − 27 is a comprehensive instrument that codes all forms of comorbid diseases in the head and neck cancer setting excepting malnutrition. This study suggests that routine collection of comorbidity will be important in future outcomes analysis and in comparing treatment results between centres. Apparent improvements in treatment outcome following newer therapeutic modalities will have to take into account any changes in the comorbidity type and burden over time.
WindEng — Research Activity in an European Training Network
Authors: Sempreviva Anna Maria , Barthelmie Rebecca , Landberg Lars , Larsen Xiaoli , Mann Jakob , Motta Maurizio , de Paus Tim , Focken Ulrich , Heinemann Detlev , Durante Francesco , Strack Martin , Christensen Lars Christian , Danielan Regis , Muri Helene , Perstrup Claus , Stefanatos Nikos , Lavagnini Alfredo , Gregow Erik , Tammelin Bengt
Published: August 2004

This paper describes research in progress, with the aim of allowing other interested individuals and organisations to relate to the work. Communications are welcome. The project ‘WindEng’, (Wind energy assessment studies and wind engineering) studies wind characteristics in different European environments so the design of wind turbines and wind farms can be improved. This is a European ‘training-through-research’ network, see www.WindEng.net , funded within the EU FP5 “Improving Human Potential” programme, “Research Training Network” activity. The Network started in September 2002 for young scientists and experienced researchers to work together on a common project. An underlying purpose is to exchange experiences and personal contacts collaboratively to strengthen academic, research and private organisations.
Modelling of Gusts for the Determination of Extreme Loads of Pitch Regulated Wind Turbines
Authors: Bierbooms Wim
Published: August 2004

A probabilistic method has been applied to determine the extreme response of pitch regulated wind turbines caused by wind speed gusts. It is assumed that the extreme loading for pitch regulated turbines is caused by gusts with an extreme rise time rather than an extreme gust amplitude. A special kind of wind field simulation, so-called constrained stochastic simulation, is dealt with in order to generate the desired gusts. It can be stated that the stochastic gusts produced in this way are, in a statistical sense, not distinguishable from gusts selected from a (very long) time series.

The theoretical mean gust shape, as well as the probability of occurrence of gusts, has been verified by measurements for modest gusts; but not, as yet, severe gusts. For the reference turbine the 50-year blade root flapping moment turned out to be much higher than the response on the IEC operating gust; this should be verified for commercial turbines.

The method is formulated in such a way that it can easily be implemented in state-of-the-art design packages for wind turbine design as used by the industry. It should be possible to extend the method to a spatial gust. The proposed more accurate description of extreme loading will enable wind turbine manufacturers to build more reliable and optimised wind turbines.
Review of Contemporary Wind Turbine Concepts and Their Market Penetration
Authors: Hansen Anca D. , Iov Florin , Blaabjerg Frede , Hansen Lars H.
Published: August 2004

The main aim of this paper is to investigate the market penetration and share of different wind turbine concepts during the years 1998–2002, a period when the increase in the wind power capacity is starting to mark an abrupt evolution (more than two GW per year). A detailed overview is performed based on suppliers market data and concept evaluation for each individual wind turbine type sold by the Top Ten suppliers over the selected five years. The investigation is processing information on a total number of approximately 90 wind turbine types from 13 different manufacturers, which have been on the Top Ten list of wind turbine suppliers during 1998 to 2002. The analysis is based on very comprehensive data, which cover approximately 76% of the accumulated world wind power installed at the end of 2002. The paper also provides an overall perspective on the contemporary wind turbine concepts, classified with respect to both their speed control ability and to their power control type. Trends for wind turbine concepts are discussed.