bluuebunny/crossref_metadata_2025 huggingface dataset:
Subsequent Hydride Substitution in (Arene)trihydridodiruthenium Complexes: Synthesis and Structure of Thiolato‐Bridged Diruthenium Cations of the Type [H2(arene)2Ru2(p‐X−C6H4−S)]+ and [H(arene)2Ru2(p‐X−C6H4−S)2]+
Authors: Tschan Mathieu J.‐L. , Chérioux Frédéric , Therrien Bruno , Süss‐Fink Georg
Published: May 2004

The cationic complexes [HRu2(η6‐arene)2{μ2‐(p‐X−C6H4)−S}2]+ and [H2Ru2(η6‐arene)2{μ2‐(p‐X−C6H4)−S}]+ (arene = 1,2,4,5‐Me4C6H2 or C6Me6; X = Br and Me) are accessible in good yields from p‐X−C6H4−SH with [H3Ru2(1,2,4,5‐Me4C6H2)2][BF4] and [H3Ru2(C6Me6)2][BF4], respectively. The dibromo derivative [HRu2(C6Me6)2(p‐Br−C6H4−S)2]+ is found to undergo double Suzuki coupling reactions with 3‐thiophene boronic acid to give [HRu2(C6Me6)2(p‐C4H3S−C6H4−S)2]+. This dibromo complex is a potential precursor for the insertion of dinuclear hydrido organometallic entities in the main chain of conjugated molecules. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
Phenyl 2‐Pyridyl Ketone and Its Oxime in Manganese Carboxylate Chemistry: Synthesis, Characterisation, X‐ray Studies and Magnetic Properties of Mononuclear, Trinuclear and Octanuclear Complexes
Authors: Milios Constantinos J. , Stamatatos Theocharis C. , Kyritsis Panayotis , Terzis Aris , Raptopoulou Catherine P. , Vicente Ramon , Escuer Albert , Perlepes Spyros P.
Published: May 2004

The use of phenyl 2‐pyridyl ketone [(ph)(2‐py)CO] and its oxime [(ph)(2‐py)CNOH] in manganese benzoate chemistry has been investigated. The reaction of an excess of (ph)(2‐py)CNOH with Mn(O2CPh)2·2H2O affords the mononuclear complex [MnII(O2CPh)2{(ph)(2‐py)CNOH}2]·1.2H2O (1·1.2H2O) in high yield. The MnII ion is coordinated by two monodentate benzoates and two N,N′‐bidentate chelating (ph)(2‐py)CNOH molecules in a cis‐cis‐trans fashion. The comproportionation reaction between Mn(O2CPh)2·2H2O and NnBu4MnO4 (3:1) in the presence of (ph)(2‐py)CNOH in MeCN/EtOH/CH2Cl2 leads to the isolation of the mixed‐valent cluster [Mn8O2(OH)2(O2CPh)10{(ph)(2‐py)CNO}4]· 4CH2Cl2 (2·4CH2Cl2) in about 55% yield. A second synthetic procedure that leads to pure 2 involves the reaction between the known starting material (NnBu4)[Mn4IIIO2(O2CPh)9(H2O)] and four equivalents of the oxime ligand in CH2Cl2. The centrosymmetric octanuclear molecule contains four MnII and four MnIII ions held together by two μ4‐O2− ligands and two μ3‐OH− ions to give the unprecedented [Mn8(μ4‐O)2(μ3‐OH)2]14+ core, with peripheral ligation provided by ten PhCO2− (two η1, four syn,syn η1:η1:μ2 and four η1:η2:μ3) and four η1:η1:η1:μ2 (ph)(2‐py)CNO− ions. The 1:1 reaction between Mn(O2CPh)2·2H2O and the ketone (ph)(2‐py)CO affords the trinuclear complex [Mn3(O2CPh)6{(ph)(2‐py)CO}2] (3) in more than 80% yield. As judged from single‐crystal X‐ray crystallography, the complex adopts a linear structure with one η1:η2:μ2 and two η1:η1:μ2 benzoates spanning each pair of metal ions. The terminal MnII ions are capped by bidentate chelating (ph)(2‐py)CO ligands. The three complexes have been characterised by IR spectroscopy. The CV study of complex 2 in CH2Cl2 reveals irreversible reduction and oxidation processes. The magnetic properties of 2 and 3 have been studied by variable‐temperature dc magnetic‐susceptibility techniques. As the temperature approaches zero, the value of the χMT product for 2 approaches zero and, thus, the octanuclear complex has an S = 0 ground state. This S = 0 ground state is explained in terms of the magnetic behaviour of the central, butterfly‐like [Mn4III(μ3‐O)2]8+ subcore. The results for 3 reveal weak antiferromagnetic coupling, with J = −2.7 cm−1 for adjacent MnII ions. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
[1,2]‐Rearrangement of Imino‐N‐heterocyclic Carbenes − Synthesis and Structures of Chelating Iminoimidazole Pd and Ni Complexes
Authors: Steiner Georg , Krajete Alexander , Kopacka Holger , Ongania Karl‐Hans , Wurst Klaus , Preishuber‐Pflügl Peter , Bildstein Benno
Published: May 2004

Imidazolium and benzimidazolium salts with an N‐iminoyl and an N′‐alkyl group are potential precursors for new bidentate [N,C] ligands which are of interest as novel steering ligands for applications of their metal complexes in homogeneous catalysis. Deprotonation of these azolium salts with potassium hydride does indeed occur, however, the initially formed imino‐N‐heterocyclic carbenes rearrange spontaneously under migration of the N‐iminoyl group from the nitrogen to the former carbene carbon with the formation of 2‐iminoyl(benz)imidazoles. These rearranged compounds are new [N,N] ligand systems, which can also be synthesized by aluminum‐assisted condensation of anilines with the corresponding 2‐acylimidazoles. Palladium and nickel [N,N] complexes have been prepared, characterized by single‐crystal X‐ray analysis, and briefly evaluated for their catalytic performance in ethylene polymerizations and in Suzuki cross‐coupling reactions. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
Surface modifications of alumina–silica glass fiber
Authors: Andrade A.L. , Ferreira J.M.F. , Domingues R.Z.
Published: May 2004

A commercial glass fiber with Al2O3 (68.4%) and SiO2 (27.6%) as major components and CaO, TiO2, Fe2O3, and CuO as minor components was used as substrate in a silica sol–gel coating process. After cleaning, fiber samples were immersed into tetraethoxysilane (TEOS) at room temperature for 1 h, and then individual fiber samples were soaked into a simulated body fluid (SBF) solution,1 and removed after 5, 10, 15, and 20 days. Zeta potential and Energy Dispersive Spectroscopy (EDS) analyses showed that the fiber surfaces were effectively coated with a silica layer, which improved the formation of an HA layer upon immersion into SBF solution for 5 days. The coating became even more continuous after 10‐day immersion. Fourier Transform Infrared Spectroscopic (FTIR) analyses confirmed that the coating layer has PO vibration bands characteristic of hydroxyapatite (HA) near 1060 and 600 cm−1. © 2004 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 70B: 378–383, 2004
Homocysteine increases the production of asymmetric dimethylarginine in cultured neurons
Authors: Selley Michael L.
Published: May 2004

Increased circulating concentrations of homocysteine may be a risk factor for Alzheimer's disease and cognitive dysfunction in normal aging. Asymmetric dimethylarginine (ADMA) is an endogenous inhibitor of endothelial nitric oxide synthase (NOS). ADMA is metabolized in neurons by the enzyme dimethylarginine dimethylaminohydrolase (DDAH). Nitric oxide plays an important role in synaptic events involved in learning and memory. We determined the effect of L‐homocysteine on ADMA accumulation and nitric oxide production in cultured rat neuronal granule cells. The incubation of neuronal granule cells with L‐homocysteine for 24 hr caused a dose‐dependent accumulation of ADMA and a dose‐dependent decrease in nitric oxide production. The addition of the sulfhydryl antioxidant pyrrolidine dithiocarbamate (PDTC) attenuated the effect of homocysteine on ADMA accumulation and nitric oxide production. DDAH activity had a decreasing dose–response relationship with increasing L‐homocysteine concentrations. The addition of PDTC caused a dose‐dependent increase in DDAH activity. The addition of the N‐methyl‐D‐aspartate receptor antagonists (±)‐2‐amino‐5‐phosphopentanoic acid and 7‐chlorokynurenate had no effect on the inhibition of DDAH by homocysteine. It is concluded that L‐homocysteine inhibits DDAH activity, thereby causing ADMA accumulation and decreasing nitric oxide production in cultured neurons. The protective effect of PDTC suggests that L‐homocysteine inactivates DDAH in neurons by reacting with the cysteine residue in its active site. The preservation of DDAH activity and the reduction of ADMA accumulation in neurons may be a new strategy for the treatment of Alzheimer's disease and cognitive impairment in normal aging. © 2004 Wiley‐Liss, Inc.
Cationic Polymerization of Vinyl Ethers in the Presence of Silyl Enol Ethers
Authors: Lang Weihong , Sarker Prodip K. , Rimmer Stephen
Published: May 2004

Summary: Vinyl ether oligomers with reactive end groups were prepared by alkylation of silyl enol ethers during propagation. Silyl enol ethers were added to the cationic polymerization of isobutyl vinyl ether, ethyl vinyl ether and methyl vinyl ether. The polymerizations were carried out under non‐living conditions so that, in the absence of added silyl enol ether, MALDI TOF mass spectrometry gave evidence for end groups other than those derived from reaction with the methanol capping agent. Addition of either phenyl‐1‐(trimethylsilyloxy)ethylene or 1‐methoxyphenyl‐1‐(trimethylsilyloxy)ethylene significantly reduced the fraction of end groups derived from intramolecular termination reactions, such as elimination, at temperatures between 21 and −78 °C. However, as in living systems lowering the reaction temperature increased the proportion of chains with the desired chain‐end functionality (i.e. aryl ketone derived from alkylation of the silyl enol ether). α‐β Elimination also produced a population of isobutyl vinyl ether oligomers with α‐β unsaturated ketone end groups.

Structure of an oligo(isobutyl vinyl ether) with a substituted phenyl ketone end group.

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Structure of an oligo(isobutyl vinyl ether) with a substituted phenyl ketone end group.
Light Scattering Studies on Ternary Polymer Blend Solutions Comprising Poly(hydroxybutyrate)
Authors: Chee Melinda J. K. , Kummerlöwe Claudia , Lechner Manfred D. , Kammer Hans‐Werner
Published: May 2004

Summary: We report on light scattering studies of polymer blend solutions in trifluoroethanol (TFE). The polymer blends comprised poly(3‐hydroxybutyrate) (PHB) in combination with poly(ethylene oxide) (PEO) and poly(ε‐caprolactone) (PCL). PHBs of two different molecular masses were used. Relevant quantities were obtained from Zimm plots. All quantities display non‐linear dependencies on blend composition. For the blend system with PEO and PHB of lower molecular mass, we observed a negative excess of the second virial coefficient, which is indicative of the miscibility of the constituents. The opposite is observed for blends with PCL. The situation changes in blends with PEO and PHB of sufficiently high molecular mass. It turns out that PEO is only miscible with PHB of high molecular mass if it is the major component. This can be concluded from both light scattering and viscosity results.

Apparent molecular mass as a function of blend composition for PEO/PHB(1) and PCL/PHB(1) solutions in TFE at 25 °C.

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Apparent molecular mass as a function of blend composition for PEO/PHB(1) and PCL/PHB(1) solutions in TFE at 25 °C.
Inversion of Phase Morphology in Polymer‐Blend Thin Films on Glass Substrates
Authors: Zong Qi , Li Zhi , Xie Xuming
Published: May 2004

Summary: The phase‐morphology inversion in two blend systems of polystyrene/poly(methyl methacrylate) (PS/PMMA) and polystyrene/poly(ε‐caprolactone) (PS/PCL) has been studied after their thin films were prepared on glass substrates by spin‐coating from a co‐solvent tetrahydrofuran (THF). Phase‐contrast microscopy (PCM), scanning‐electron microscopy (SEM) equipped with energy dispersive X‐ray spectroscopy (EDS), and atomic force microscopy (AFM) were used to obtain information on the morphology of the thin films during heat treatment. It was found that the PMMA‐rich and PCL‐rich phases are always continuous after annealing in either of the PS/PMMA and PS/PCL blend thin films, even though the PMMA and PCL are minor components in the blends. This should result from the better wetting abilities of PMMA and PCL on a glass substrate than PS in the blends. The effect of the viscosity in the evolution of the phase structure was also investigated by changing the molecular weight of PS in the PS/PCL blend thin films. Further more, it is found that the phase‐separation process and the wetting phenomenon of the blends on the glass substrate can be strongly suppressed after adding PS‐block‐PMMA diblock copolymer to the PS/PMMA blend system as a compatibilizer.

Scheme of the longitudinal section of the evolution of the phase structure of a PS:PMMA (70:30 w:w) blend film.

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Scheme of the longitudinal section of the evolution of the phase structure of a PS:PMMA (70:30 w:w) blend film.
Conformational Transition between Random Coil and Helix of Copolymers of N‐Propargylamides
Authors: Deng Jianping , Tabei Junichi , Shiotsuki Masashi , Sanda Fumio , Masuda Toshio
Published: May 2004

Summary: Copolymerization of two N‐propargylamides bearing pendent groups with different lengths [monomer 4, HCCCH2NHCO(CH2)4H; monomer 8, HCCCH2NHCO(CH2)8H] was carried out and the conformational transition behavior of copolymers with different compositions was examined systematically. The copolymers could form relatively stable helices even though both of the corresponding homopolymers, poly(4) and poly(8), could not take a stable helical conformation under the same conditions. The helix content of copolymers reached a maximum when the content of monomer 8 was 61%. These results are explained in terms of the idea that the copolymers have higher cis‐content and that the intramolecular hydrogen bonding is more effective in these copolymers compared with the corresponding homopolymers.

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Inter‐ and Intramolecular Crosslinking Kinetics: Partitioning According to Number of Crosslinks
Authors: Li Rujun , McCoy Benjamin J.
Published: May 2004

Summary: Intramolecular crosslinking is important in many processes, including nanoparticle fabrication, but quantitative models of the kinetics have not been extensively investigated. We propose a distribution kinetics analysis for simultaneous intramolecular and intermolecular crosslinking. For realistic cases, moment equations can be solved and crosslink density computed according to the number of crosslinks. An analytical solution for the ratio of intramolecular to intermolecular crosslinking rates varies inversely with the initial polymer concentration and initial molecular weight, in agreement with published experimental data.

Time dependence of crosslink density pcd in a batch reactor for ω1 = ω2 = 1 with κ2 = 1 and κ1 = 0, 0.2, 0.5, and 1 (lines 1, 2, 3, and 4), and κ2 = 0 and κ1 = 1 (line 5). pcd increases linearly with time for all cases.

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Time dependence of crosslink density pcd in a batch reactor for ω1 = ω2 = 1 with κ2 = 1 and κ1 = 0, 0.2, 0.5, and 1 (lines 1, 2, 3, and 4), and κ2 = 0 and κ1 = 1 (line 5). pcd increases linearly with time for all cases.
Continuous Reversible Addition‐Fragmentation Chain Transfer Polymerization in Miniemulsion Utilizing a Multi‐Tube Reaction System
Authors: Russum James P. , Jones Christopher W. , Schork F. Joseph
Published: May 2004

Summary: A unique, multi‐tube, continuous reactor has been successfully designed and implemented for the study of reversible addition‐fragmentation chain transfer (RAFT) in miniemulsions. Data collection is greatly enhanced by the ability to simultaneously collect samples at five different residence times. The results of a styrene homopolymerization show that kinetically, the reactor exhibits similar behavior to a batch reaction. Number‐average molecular weights increased linearly with conversion, typical of living polymerizations.

The number‐average molecular weight of the polymers produced in the tubular reactor increased linearly with conversion, indicative of a controlled polymerization.

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The number‐average molecular weight of the polymers produced in the tubular reactor increased linearly with conversion, indicative of a controlled polymerization.
Cover Picture: Macromol. Rapid Commun. 10/2004
Authors: Severn John R. , Chadwick John C.
Published: May 2004

Cover: Effective immobilization and activation of Cp2TiCl2 and other single‐site olefin polymerization catalysts has been achieved using spherical supports of type MgCl2/AlRn(OEt)3‐n, obtained by reaction of AlR3 with adducts of MgCl2 and ethanol. Polyethylene having spherical particle morphology and narrow molecular weight distribution was obtained, without the use of MAO or borate activators.

Further details can be found in the Communication by J. R. Severn and J. C. Chadwick* on page 1024.
Cover Picture: Macromol. Theory Simul. 4/2004
Authors: de Jong Johan , ten Brinke Gerrit
Published: May 2004

Cover: The picture on the cover shows the spontaneous curvature in an alternating copolymacromonomer brush with phase separated side chains.

Further details can be found in the Full Paper by J. de Jong* and G. ten Brinke on page 318.
Acute stimulation in the external segment of the globus pallidus improves parkinsonian motor signs
Authors: Vitek Jerrold L. , Hashimoto Takao , Peoples John , DeLong Mahlon R. , Bakay Roy A.E.
Published: May 2004

High frequency (>100Hz) electrical stimulation in both the external (GPe) and internal (GPi) segments of the globus pallidus was effective in improving parkinsonian motor signs. Improvement generally occurred at short latency (<5–10 seconds) in both GPe and GPi but was often (50% of the time) delayed in GPi. Dyskinetic movements were observed during stimulation within GPe and GPi but were more frequent in GPe (20% vs. 9%). These findings suggest that electrical stimulation in both GPe and GPi may ameliorate parkinsonian motor signs. The mechanisms responsible for these observations, however, may differ. The tendency for delayed responses with GPi stimulation suggests a more complex spatial–temporal profile of stimulation on the electrical activity of GPi neurons and/or its effect on network activity in pallido‐thalamo‐cortical circuitry. The rarity of delayed effects with GPe stimulation suggests a more direct role of synaptic inhibition or normalization of neuronal activity of GPi either directly by means of activation of striatopallidal fibers passing through GPe (direct pathway), by means of activation of GPe→GPi or GPe→subthalamic nucleus projections (indirect pathway) or indirectly by means of the tonic activation of adjacent fiber pathways. These data provide a rationale for the exploration of electrical stimulation in GPe in patients with medically intractable Parkinson's disease and provide a basis on which to develop further investigations into the use of chronic electrical stimulation for the treatment of Parkinson's disease and other movement disorders. © 2004 Movement Disorder Society
Pilot efficacy and tolerability: A randomized, placebo‐controlled trial of levetiracetam for essential tremor
Authors: Handforth Adrian , Martin Fredricka C.
Published: May 2004

The purpose of this pilot single‐site study was to assess efficacy and safety of levetiracetam for essential tremor, using a placebo‐controlled, double‐blind, randomized crossover design with an interim analysis planned after completion of the first 10 to 15 subjects. The study was designed to detect a mean 30% reduction in composite tremor score, comparable to that of primidone or propranolol, which can be demonstrated with 30 or fewer subjects. Each treatment arm included baseline tremor assessments, a 4‐week medication titration, 2 weeks of stable dose, and treatment tremor assessments. Levetiracetam was titrated to 3,000 mg/day or to a lower maximal tolerated dose. The median age was 72 years, with 28 years median tremor duration. There was no statistically significant difference in response between placebo and levetiracetam on any tremor rating scale or accelerometry measure. The 95% confidence interval for the true mean difference between placebo and levetiracetam treatments was +18.5 to −22.5%, which excludes the minimum 30% drop required to consider levetiracetam clinically effective to a degree comparable to primidone or propranolol. Whether levetiracetam has lesser‐degree antitremor efficacy was not addressed in this pilot study. © 2004 Movement Disorder Society
Movement disorders after intervertebral disc surgery: Coincidence or causal relationship?
Authors: Capelle Hans‐Holger , Wöhrle Johannes C. , Weigel Ralf , Bäzner Hansjörg , Grips Eva , Krauss Joachim K.
Published: May 2004

It is well known that brain injury or central traumatic lesions may result in the subsequent appearance of movement disorders such as dystonia or tremor. The concept that peripheral lesions to neural structures may be involved in the pathogenesis of movement disorders has been discussed controversely but has gained more widespread acceptance only recently. Here, we report on 6 patients who developed movement disorders after spinal disc surgery. The movement disorders became manifest with a delay of 1 day to 12 months after surgery. Of the six patients, 4 underwent cervical disc surgery, and 2 patients were operated on for lumbar disc herniation; 2 patients presented with paroxysmal kinesigenic segmental dystonia, 1 patient with focal dystonia, 2 with unilateral tremor, and 1 with bilateral tremor. The appearance of the movement disorder was associated with persistent dermatomal or segmental pain. In all patients, the anatomic distribution of the movement disorder was related to the nerve root or spinal segment of the corresponding disc level and the manifestation was in close temporal relation to the surgery. We conclude that spinal disc surgery may be another, thus far neglected, cause for movement disorders. The postoperative pain syndrome in all patients should be considered as an important factor of pathogenesis. Overall, movement disorders associated with disc surgery appear to be rare, yet they may cause significant discomfort to the affected individual. © 2004 Movement Disorder Society
A rapid densitometric method for the analysis of hyoscyamine and scopolamine in solanaceous plants and their transformed root cultures
Authors: Berkov Strahil , Pavlov Atanas
Published: May 2004

A rapid and convenient method for sample preparation and simultaneous densitometric quantiﬁcation of hyoscyamine (1) and scopolamine (2) has been developed. The alkaloid proﬁles of plant samples, as well as the content of 1 and 2, determined by TLC‐densitometry corresponded well with those obtained using a GC method. The proposed method is simple and sensitive and can be used for the routine assay of 1 and 2, and for screening for alkaloid‐rich and biochemically‐interesting transformed root cultures and intact solanaceous plants. Copyright © 2004 John Wiley & Sons, Ltd.
An electrophoretic proﬁling method for thiol‐rich phytochelatins and metallothioneins
Authors: Fan Teresa W‐M. , Lane Andrew N. , Higashi Richard M.
Published: May 2004

Thiol‐rich peptides such as phytochelatins (PCs) and metallothioneins (MTs) are important cellular chelating agents which function in metal detoxiﬁcation and/or homeostasis. The variations in molecular sizes and lack of chromophores of these peptides make their analysis difﬁcult. This paper reports an electrophoresis‐based method for a broad screen of thiol‐rich peptides and proteins. The method uses the thiol‐selective ﬂuorescent tag, monobromobimane, coupled with Tricine–sodium dodecyl sulphate–urea polyacrylamide gel electrophoresis for a sensitive determination of both PCs and MTs. Results for PCs were conﬁrmed by two‐dimensional NMR and HPLC‐tandem MS analyses. Sample throughput is substantially improved over chromatography‐based methods through parallel sample analysis in 1 h of electrophoretic separation. The method is versatile in that peptides ranging from glutathione to large proteins can be analysed by simple modiﬁcation(s) of the extraction and electrophoretic conditions, and the nature of the method supports serendipitous detection of unexpected or novel thiol metabolites. Copyright © 2004 John Wiley & Sons, Ltd.
Low‐molecular‐weight components of olive oil mill waste‐waters
Authors: DellaGreca Marina , Previtera Lucio , Temussi Fabio , Zarrelli Armando
Published: May 2004

A new lignan 1‐hydroxy‐2‐(4‐hydroxy‐3‐methoxyphenyl)‐6‐(3‐acetyl‐4‐hydroxy‐5‐methoxyphenyl)‐3,7‐dioxabicyclo[3.3.0]octane, the secoiridoid 2H‐pyran‐4‐acetic acid,3‐hydroxymethyl‐2,3‐dihydro‐5‐(methoxycarbonyl)‐2‐methyl‐, methyl ester, the phenylglycoside 4‐[β‐d‐xylopyranosyl‐(1→6)]‐β‐d‐glucopyranosyl‐1,4‐dihydroxy‐2‐methoxybenzene and the lactone 3‐[1‐(hydroxymethyl)‐1‐propenyl] δ‐glutarolactone were isolated and identiﬁed on the basis of spectroscopic data including two‐dimensional NMR, as components of olive oil mill waste‐waters. The known aromatic compounds catechol, 4‐hydroxybenzoic acid, protocatechuic acid, vanillic acid, 4‐hydroxy‐3,5‐dimethoxybenzoic acid, 4‐hydroxyphenylacetic acid, 3,4‐dihydroxyphenylacetic acid, tyrosol, hydroxytyrosol, 2‐(4‐hydroxy‐3‐methoxy)phenylethanol, 2‐(3,4‐dihydroxy)phenyl‐1,2‐ethandiol, p‐coumaric acid, caffeic acid, ferulic acid, sinapic acid, 1‐O‐[2‐(3,4‐dihydroxy)phenylethyl]‐(3,4‐dihydroxy)phenyl‐1,2‐ethandiol, 1‐O‐[2‐(4‐hydroxy)phenylethyl]‐(3,4‐dihydroxy)phenyl‐1,2‐ethandiol, d(+)‐erythro‐1‐(4‐hydroxy‐3‐methoxy)‐phenyl‐1,2,3‐propantriol, p‐hydroxyphenethyl‐β‐d‐glucopyranoside, 2(3,4‐dihydroxyphenyl)ethanol 3β‐d‐glucopyranoside, and 2(3,4‐dihydroxyphenyl)ethanol 4β‐d‐glucopyranoside were also conﬁrmed as constituents of the waste‐waters. Copyright © 2004 John Wiley & Sons, Ltd.
An ultraviolet‐finite Hamiltonian approach on the noncommutative Minkowski space
Authors: Bahns D.
Published: May 2004

This is an exposition of joint work with S. Doplicher, K. Fredenhagen, and G. Piacitelli on field theory on the noncommutative Minkowski space [1]. The limit of coinciding points is modified compared to ordinary field theory in a suitable way which allows for the definition of so‐called regularized field monomials as interaction terms. Employing these in the Hamiltonian formalism results in an ultraviolet finite S‐matrix.
Transplanckian dispersion relation and entanglement entropy of blackhole
Authors: Chang D. , Chu C.‐S. , Lin F.‐L.
Published: May 2004

The quantum correction to the entanglement entropy of the event horizon is plagued by the UV divergence due to the infinitely blue‐shifted near horizon modes. The resolution of this UV divergence provides an excellent window to a better understanding and control of the quantum gravity effects. We claim that the key to resolve this UV puzzle is the transplanckian dispersion relation. We calculate the entanglement entropy using a very general type of transplanckian dispersion relation such that high energy modes above a certain scale are cutoff, and show that the entropy is rendered UV finite. We argue that modified dispersion relation is a generic feature of string theory, and this boundedness nature of the dispersion relation is a general consequence of the existence of a minimal distance in string theory.
Operator product expansion and zero mode structure in logarithmic CFT
Authors: Flohr M. , Krohn M.
Published: May 2004

The generic structure of 1‐, 2‐ and 3‐point functions of fields residing in indecomposable representations of arbitrary rank are given. These in turn determine the structure of the operator product expansion in logarithmic conformal field theory. The crucial role of zero modes is discussed in some detail.
Fractionally charged instantons
Authors: Ford C.
Published: May 2004

Fractionally charged Yang‐Mills instantons on compact and non‐compact tori are discussed.
D‐branes and time dependent dynamics in two dimensional string theory
Authors: Gutperle M.
Published: May 2004

We review recent progress in understanding unstable branes and their decays in two dimensionsional noncritical string theory using the dual formulation of the string theory as a matrix model.
A trio of dualities: walls, trees and cascades
Authors: Franco S. , Hanany A. , He Y.‐H.
Published: May 2004

We study the RG flow of 𝒩 = 1 world‐volume gauge theories of D3‐brane probes on certain singular Calabi‐Yau threefolds. Taking the gauge theories out of conformality by introducing fractional branes, we compute the NSVZ beta‐function and follow the subsequent RG flow in the cascading manner of Klebanov‐Strassler. We study the duality trees that blossom from various Seiberg dualities and encode possible cascades. We observe the appearance of duality walls, a finite limit energy scale in the UV beyond which the dualization cascade cannot proceed. Diophantine equations of the Markov type characterize the dual phases of these theories. We discuss how the classification of Markov equations for different geometries into families relates the RG flows of the corresponding gauge theories.
Space‐time singularities and the Kähler cone
Authors: Järv L. , Mayer C. , Mohaupt T. , Saueressig F.
Published: May 2004

We review recent results on the interplay between the five‐dimensional space‐time and the internal manifold in Calabi‐Yau compactifications of M‐theory. Black string, black hole and domain wall solutions as well as Kasner type cosmologies cannot develop a naked singularity as long as the moduli take values inside the Kähler cone.
Instanton solutions for the universal hypermultiplet
Authors: Davidse M. , de Vroome M. , Theis U. , Vandoren S.
Published: May 2004

We expand our previous analysis on fivebrane and membrane instanton solutions in the universal hypermultiplet, including near‐extremal multi‐centered solutions and mixed fivebrane‐membrane charged instantons. The results are most conveniently described in terms of a double‐tensor multiplet.
Gauging maximal supergravities
Authors: de Wit B. , Samtleben H. , Trigiante M.
Published: May 2004

We review recent progress in the gauging of maximal supergravity theories.
Brane‐bulk energy exchange and cosmological acceleration
Authors: Kiritsis E.
Published: May 2004

The consequences for the brane cosmological evolution of energy exchange between the brane and the bulk are analyzed. A rich variety of brane cosmologies is obtained, depending on the precise mechanism of energy transfer, the equation of state of brane‐matter and the spatial topology. An accelerating era is generically a feature of the solutions.
Double‐trace deformations and SL(2,Z) action on three‐dimensional CFTs
Authors: Petkou A.C.
Published: May 2004

I discuss the connection between certain double‐trace deformations of three‐dimensional CFTs and a natural \documentclass{article}\pagestyle{empty}\usepackage{amssymb}\begin{document}$SL(2,\mathbb{Z})$\end{document} action on their two‐point functions that involve higher‐spin currents. I argue that this connection is a salient feature of the holography of Higher‐Spin gauge theories on AdS4.
The AdS/CFT correspondence in the PP‐wave limit
Authors: Petrini M. , Russo R. , Tanzini A.
Published: May 2004

We consider the correspondence between IIB string theory on the maximally supersymmetric PP‐wave and the BMN sector of 𝒩 = 4 SYM theory. At the level of the interacting (string) theory, the matching between these two descriptions is not yet fully understood. Here we review the tests supporting the simple proposal that relates the 3‐string interaction to the correlation functions among the BMN operators.
Simulation of vegetation cover on sidewalks in Denmark
Authors: Kristensen Kristian , Hansen Preben K , Kristoffersen Palle
Published: May 2004

Data from five 3‐year experiments comparing different strategies of non‐chemical weed control were analysed in order to set up a model that could be used for simulating further strategies. The treatments included different frequencies and effects of weed control using flaming, steaming and weed brushing. Each plot consisted of about 100 m of sidewalk. The amount of weed on the sidewalks was recorded several times during the 3‐year period using a system of cameras mounted on a Terrain Vehicle moving on the sidewalk and post processing using image analyses of extracted images. The percentage of sidewalk covered by weed was estimated on the basis of the image analyses. The model used for describing the weed coverage comprises three components. The first component describes the growth of weeds; the second describes reduction caused by wearing and decay of weeds in the autumn and the third describes the reduction caused by weed control using weed brushing, steaming and flaming. The parameters of the model were estimated from the data for later use for simulating additional strategies. Copyright © 2004 Society of Chemical Industry
Contribution of non‐agricultural pesticides to pesticide load in surface water
Authors: Skark Christian , Zullei‐Seibert Ninette , Willme Uwe , Gatzemann Ulrich , Schlett Claus
Published: May 2004

Two small creeks, tributaries of the River Ruhr near Schwerte, Federal Republic of Germany, were investigated to reveal the regional agricultural and non‐agricultural sources of pesticide inputs and the main pathways to surface water. In addition, the receiving water was monitored for pesticides. The watersheds are situated at the northern margin of the Rhenian Schiefergebirge, a highland landscape in North‐Rhine–Westphalia. Solid carboniferous shale is covered by a shallow layer of quaternary unconsolidated rock (porous aquifer thickness <5 m). Occurrence of herbicides such as chlortoluron, isoproturon and terbuthylazine in surface water could be due to their broad agricultural application in regional dominant crops, such as barley, wheat and maize. Occurrence of diuron and glyphosate results from their use in residential settlements and industrial areas as well as from weed control on railway tracks. Atrazine concentrations up to 0.8 µg litre−1 indicated recent use of this herbicide, which has been banned since 1991, and was also the result of non‐agricultural applications. Pathways for pesticide input to the receiving waters were related to both surface run‐off and underground passage. Two‐thirds of the observed diuron load in the surface water resulted from an input by run‐off. This was expected as a result of total herbicide application targets to sealed surfaces infringing current regulations and recommendations. Diuron load varied between 0.6 and 1.2% of the estimated amount applied annually in the investigated catchments. Non‐agricultural pesticide use contributed more than two‐thirds of the whole observed pesticide load in the tributaries and at least one‐third in the River Ruhr. Copyright © 2004 Society of Chemical Industry
Turfgrass management and weed control without pesticides on football pitches in Denmark
Authors: Larsen Søren U , Kristoffersen Palle , Fischer Jørgen
Published: May 2004

Management of turfgrass on football pitches without pesticides involves a considerable challenge for weed control. By improving conditions for grass growth by cultural practices, weeds may be repressed by stronger competition from the grass. A 3‐year field trial on 37 football pitches investigated the effects of various cultural management practices on percentage grass, weed and bare ground, respectively. The trial included twelve different treatments, comprising different combinations of fertiliser level and cultural methods, including two types of spring‐tine harrow, vertical cutting, over‐seeding, and top‐dressing. Some treatments resulted in significant differences in percentage grass and weed cover, but not in percentage bare ground. However, other factors, such as locality of the football pitch, zone on the pitch, month, year, playing frequency, cutting frequency and, particularly, ground cover at the beginning of the trial, also contributed considerably to the variation in ground cover, indicating that established weeds are difficult to eradicate. Copyright © 2004 Society of Chemical Industry
Herbicide loss following application to a railway
Authors: Ramwell Carmel T , Heather Andrew IJ , Shepherd Anthony J
Published: May 2004

Railways have been identified as a potential source of herbicides detected in surface and groundwaters, but there are few data to support this theory. Two studies were undertaken to investigate the fate of herbicides applied to railway trackbeds: a pilot study in a section of a disused, but intact, cutting where runoff and throughflow were sampled from trenches adjacent to the treated area, and a larger scale study on 0.75 km of embankment where surface water from the drainage ditch at the base of the embankment and groundwater were sampled. In the pilot study, peak concentrations of atrazine, diuron and glyphosate (1280, 210 and 15 µg litre−1 respectively) were detected 6 days after treatment (DAT). Oxadiazon, oryzalin and isoxaben were not detected above their limits of quantification. Lower concentrations were detected 81 DAT (10 and 0.8 µg litre−1 of atrazine and glyphosate respectively). In the larger scale study, herbicides were not detected, in either the surface water or groundwater, at concentrations above the limit of detection that could be attributed to application to the railway. Rainfall volume and depth to sampling point may partly explain the different results obtained from the two studies. The findings are compared with herbicide losses from other ‘hard surfaces’. Copyright © 2004 Society of Chemical Industry
Use of imazapyr against Equisetum arvense on Swedish railway tracks
Authors: Torstensson Lennart , Börjesson Elisabet
Published: May 2004

Since glyphosate has been used extensively for weed control in Swedish railway tracks, common horsetail (Equisetum arvense L), previously relatively rare, has become very common. Glyphosate, although effective against most other weeds found on railway tracks, gives poor control of E arvense, so that heavy infestation with this weed is now common. Imazapyr (applied as a 250 g AE litre−1 SL, Arsenal) has controlled E arvense, but is known to be very mobile. Adequate control of the weed requires application of ≥4 litres ha−1 of imazapyr SL but environmental factors preclude the use of >2 litres ha−1. A suitable strategy was found to be one application of imazapyr SL at 2 litres ha−1 in each of two successive years but best weed control was obtained by supplementing imazapyr in the first year with glyphosate 360 g AE litre−1 SL (RoundUp Bio) at 3 litres ha−1. Copyright © 2004 Society of Chemical Industry
The fate of imazapyr in a Swedish railway embankment
Authors: Börjesson Elisabet , Torstensson Lennart , Stenström John
Published: May 2004

The long‐term fate of the herbicide imazapyr [2‐(4‐isopropyl‐4‐methyl‐5‐oxo‐2‐imidazolin‐2‐yl)nicotinic acid] applied to a Swedish railway embankment was studied. Imazapyr was applied at 750 and 1500 g ha−1 by a spraying train used for full‐scale herbicide treatment operations. Soil and groundwater were sampled twice a year for 8 years after application of the herbicide, and the dissipation of imazapyr was studied by HPLC analysis of the residues in soil and groundwater. A clean‐up procedure including solid‐phase extraction was performed prior to detection by HPLC. Recoveries of imazapyr from soil and water samples were 76–98% and 61–90%, respectively, and detection levels were 0.003 mg kg−1 and 0.05 µg litre−1, respectively. Sorption, desorption and microbial amount and activity were also measured at the two locations. The organic matter content correlated positively and the pH negatively to the adsorption of imazapyr on soil, and increasing organic matter contents decreased desorption. Apart from the 0–10‐cm top layers of both sites, the microbial amount and activity were small. The main proportion of imazapyr was found in the upper 30 cm of the soil, and degraded with a half‐life in the range 67–144 days. Small amounts were transported to lower soil layers and to the groundwater in proportion to the amounts applied. Traces of imazapyr were detected in the groundwater even 8 years after application. It was concluded that environmental risks from the use of herbicides on railway embankments could be reduced by including adsorption layers in the embankment during their construction and by reducing the dose of the herbicide used. Copyright © 2004 Society of Chemical Industry
A spatial analysis of childhood mortality in West Africa
Authors: Balk Deborah , Pullum Thomas , Storeygard Adam , Greenwell Fern , Neuman Melissa
Published: May 2004

It is suggested that environmental or geographical factors (e.g. population density, climate and disease environment) play an important role in determining infant and child survival above and beyond that played by individual and household level factors. Only recently, however, have relevant spatial data become available and have demographic survey data systematically recorded geographical location of surveyed households, or has the technology to integrate these data become accessible. This study estimates the risk of infant and child death in ten West African countries attributable to individual, household and spatially explicit geographical factors; 120,000 births occurring in the 10 years prior to the 1997–2001 Demographic and Health Survey dates are evaluated. Results from a generalised linear model show that spatial variables explain away a good deal of the country‐specific variation in mortality, and that they are associated with (and may be mediated by) the household characteristics. Implications for research and policy are addressed. Copyright © 2004 John Wiley & Sons, Ltd.
Magnetic properties of amorphous Ge–Cr thin films fabricated by thermal evaporation
Authors: Paek W. B. , Kim J. , Lim S. H.
Published: May 2004

Ferromagnetic ordering at room temperature is observed in amorphous Ge100−xCrx (x in at.%) thin films fabricated by thermal co‐evaporation over a wide composition range up to x = 39. High resolution transmission electron microscopy results indicate that the microstructure is mostly amorphous, except for at x = 15 (close to eutectic composition) and 39 where crystalline precipitates of Ge and the intermetallic Ge19Cr11 compound are respectively formed in an amorphous matrix. The saturation magnetization at room temperature exhibits a maximum value of 2.5 emu/cc at x = 29 and the compositional dependence of saturation magnetization is supported by the microstructural results. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Magnetoelastic properties of Co/Pd nanomultilayer films
Authors: Jeong Jong‐Ryul , Shin Sung‐Chul
Published: May 2004

The magnetoelastic properties of (6 Å Co/20 Å Pd)6 nanomultilayer films have been investigated using an ultrahigh vacuum (UHV) in situ stress and magnetoelastic coupling (MEC) constant measurement system. In situ stress measurement reveals that stress existing in the Pd sublayers is tensile up to the second Pd sublayer deposition and it gradually changes to compressive after the deposition of the third Pd sublayer. Interestingly, the MEC constant of the Co/Pd nanomultilayer continuously increases with increasing Pd layer thickness from 0 to 20 Å in the sixth Pd sublayer. It is found that the evolution of the MEC constant is intimately related with the film strain rather than interface formation, and second‐order strain correction is necessary to describe the dependence of the MEC constant on the Pd thickness. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
RF integrated magnetic thin film noise suppressor on coplanar transmission line
Authors: Kim Ki Hyeon , Yamaguchi Masahiro
Published: May 2004

Rf integrated noise suppressors were fabricated by integration of magnetic films using a micro‐lithography process. CoNbZr magnetic films with various dimensions were stacked on coplanar transmission lines. The rf noise suppressor was composed of magnetic film (CoNbZr)/polyimide/Cu transmission line/seed layer (Ti/Cu)/glass substrate. The CoNbZr magnetic films (4πMs ∼ 10 kG, Hk = 8.5 Oe, ρ = 120 μΩ cm, fFMR = 0.8 GHz) were deposited by rf sputtering. The signal attenuation of the transmission line was estimated by extracting S‐parameters (S11, S21) from a network analyser up to 20 GHz. In the case of 2000 μm wide, 15 mm long and 2 μm thick magnetic films, the magnitude of signal attenuation at the resonance (dip) point was increased greatly to about –56 dB compared with a coplanar transmission line without magnetic film. In the case of 50 μm wide, 15 mm long and 2 μm thick magnetic films, insertion loss and power loss except for the resonance frequency region was very small in comparison with that of 2000 μm wide magnetic films. These results are related to the ferromagnetic resonance and eddy current loss due to the dimension of the magnetic film on the coplanar transmission line with the 50 μm wide signal line. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Substrate effect on low‐field transport properties of La–Pb–Mn–O granular‐type thin films
Authors: Lee Hi Min , Shim In‐Bo , Kim Chul Sung
Published: May 2004

This paper studied the low‐field tunnel‐type transport characteristics of polycrystalline and c‐axis‐oriented La0.7Pb0.3MnO3 (LPMO) thin films. Polycrystalline thin films were fabricated on SiO2/Si(100) substrate (film A), on SiO2/Si substrate with yttria‐stabilized zirconia (YSZ) buffer layer (film B), and on c‐axis‐oriented thin film grown on LaAlO3(001) (LAO) single crystal substrate (film C) using the soft‐chemical deposition method. A YSZ buffer layer acts as a barrier against inter‐diffusion. As a result, it decreases the amount of dead layers generated from the interface and helps to produce qualitative films for application of magnetoresistive elements. The magnetoresistance (MR) ratio was 0.52%, 0.7%, and 0.4% for film A, film B, and film C under the applied field of 500 Oe at 300 K, respectively. The polycrystalline film had denser boundaries than the c‐axis oriented film, i.e., the polycrystalline film gave more effective potential barrier regions than the c‐axis oriented film. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Preparation of boron carbide thin films from reactive sputtering of boron
Authors: Lee K. E. , Kim C. O. , Park M. J. , Kim J. H.
Published: May 2004

Boron carbide thin films were prepared by RF magnetron sputtering. The films were deposited onto CoCr/Cr/SiO2/Si(100) substrates with an RF power of 25, 50 and 75 W in the range of 200 °C. The reactive gas was introduced up to 1.5 vol% (CH4/(Ar + CH4)) during deposition, and the resulting composition of the films matched these ratios, as observed by Auger electron spectroscopy. In X‐ray photoelectron spectroscopy, two well‐resolved peaks in C (1s) spectra were observed around 284 eV, indicating C–C bond at 284.5 eV and B–C bond at 283.5 eV. The X‐ray diffraction of these films revealed the amorphous or nanocrystalline characteristics. At the deposition conditions of 75 W, 100 °C and 1.0 vol%, the nano‐indented films were hardened to 16 GPa and the scratched surfaces endured load of 50 N. In the wear test, the coefficient of friction was also measured down to 0.15. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Magnetically and electrically tunable devices using ferromagnetic/ferroelectric ceramics
Authors: Kim Jang‐Yong , Koh Jung‐Hyuk , Song Jae‐Sung , Grishin Alex
Published: May 2004

There has been a growing interest in tunable devices applications such as filters, phase shifters, and resonators. Both of ferromagnetic and ferroelectric materials have strong advantages in the high tunability and stability. Therefore many reports have been published by employing ferrite or dielectric materials for high frequency devices applications. Both of controllable dielectric permittivity and magnetic permeability were considered one of the solutions for impedance matching in tunable devices. In this experiment ferromagnetic/ferroelectric composite ceramics were successfully fabricated without any cracking or shrinkage. Fabricated ferromagnetic/ferroelectric composite ceramic showed ferroelectric properties of P–E hysteresis and magnetic properties of B–H hysteresis loops. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)