bluuebunny/crossref_metadata_2025 huggingface dataset:
Tuning Molecular Recognition of RNA and DNA via Sugar Modification
Authors: Leumann Christian J.
Published: June 2006

This minireview highlights three aspects of our recent work in the area of sugar modified oligonucleotide analogues. It provides an overview over recent results on the conformationally constrained analogue tricyclo-DNA with special emphasis of its antisense properties, it summarizes
results on triple-helix forming oligodeoxynucleotides containing pyrrolidino-nucleosides with respect to DNA recognition via the dual recognition mode, and it highlights the advantageous application of the orthogonal oligonucleotidic pairing system homo-DNA in molecular beacons for
DNA diagnostics.
Targeting Posttranslational Modifications – Perspectives for Biocatalyst Engineering
Authors: Pscheidt Beate , Weis Roland , Glieder Anton
Published: June 2006

Engineering posttranslational modifications is of great importance in biomedical research. Recent advances in the field of biocatalyst engineering expanded the strategy of targeting posttranslational modifications to a novel research field, i.e. rendering the particular enzyme
more efficient for the desired biocatalytic conversion. Thus enzymes could be trimmed to higher fitness for technical applications e.g. by improved activity and/or prolonged life-time. Furthermore, bottlenecks during enzyme expression caused by posttranslational processing in the cell
can be overcome. Focusing especially on recent approaches in our laboratory, this article presents strategies for targeted manipulations of selected posttranslational modifications.
Safe Oxidation Reactions. Development of an Explosion Protection System from Process Development Lab to Large Scale Production Plant
Authors: Kuppinger Myriam , Obermüller Iris , Peterhans Bruno
Published: June 2006

The systematic development of an explosion protection system for an oxidation reaction in pure oxygen following a thorough risk analysis is described. By evaluating both probability and consequences of all risks identified it could be shown that an explosion in the investigated system
cannot be prevented completely. Therefore the emphasis of the system was to protect humans and the environment from the consequences of this residual risk. Several design alternatives were considered. Only an explosion decoupling system, consisting of a combination of a flame interrupter and
a fast-acting valve can fulfill this task. The successful start-up and running production process up to now confirm the chosen path.
Theoretical Studies on the Electronic Properties and the Chemical Bonding of Transition Metal Complexes using DFT and Ligand Field Theory
Authors: Atanasov Mihail , Daul Claude
Published: June 2006

The research activity within our laboratory of computational chemistry at the University of Fribourg is presented. In this review, a brief outline of a recently proposed Ligand Field Density Functional Theory (LFDFT) model for single nuclear and its extension to dimer transition metal
complexes is given. Applications of the model to dinuclear complexes are illustrated for the interpretation of exchange coupling in the bis-?-hydroxo-bridged dimer of Cu(II) and to the description of the quadruple metal-metal bond in Re2Cl82?. The
analysis of the chemical bonding is compared with results obtained using other approaches, i.e. the Extended Transition State model and the Electron Localization Function. It is shown that the DFT supported Ligand Field Theory provides consistent description of the ground and excited
state properties of transition metal complexes.
'Measuring' Electron Delocalization in ?-Conjugated Systems
Authors: Bruschi Maurizio , Giuffreda Maria Grazia , Lüthi Hans Peter
Published: June 2006

For the design of donor/acceptor functionalized ?-conjugated compounds, electron delocalization is a widely used concept to make structure–property predictions. In this work we present a method based on the NBO analysis, which allows selected conjugation paths in these compounds
to be studied. The method maps information obtained from complex quantum calculation onto simple concepts used by general chemists.
L'Ecole de Pharmacie Genève-Lausanne: un rôle de précurseur, un espoir à concrétiser L'Ecole de Pharmacie Genève-Lausanne: un rôle de précurseur, un espoir à concrétiser
Authors: Arlettaz Dominique
Published: June 2006

On July 8th, 2003, the Rectors of the Universities of Geneva and Lausanne signed the Convention regulating the transfer to the University of Geneva of the Section of Pharmacy of the Faculty of Sciences of the University of Lausanne. At this date, the Geneva-Lausanne School
of Pharmacy (EPGL) was created to benefit from complementarities between researchers in pharmaceutical sciences of the lemanic area. The EPGL must be regarded as a precursory example of a strong collaboration between two universities. Its first mission is to guarantee to future students a
varied study program compatible with the model of Bologna and teaching by a sufficient number of high ranking professors and researchers. Its second role is to gain more knowledge in the principal areas of pharmaceutical sciences by developing research projects of great value and by exploring
new routes likely to generate new information. The University of Lausanne does not limit its action to the large political and financial efforts invested into this adventure but will follow closely the success of the EPGL and the interactions which it will be able to initiate with researchers
in life sciences of the whole area. Science evolves at an amazing rate and the EPGL must contribute to this evolution by its dynamism in order to be well equipped to face the international competition of the best researchers working in the field of pharmaceutical sciences.
Study by Confocal Laser Scanning Microscopy of the Influence of Hydrogels on the Wound Healing Rate after Mechanical Corneal Injury
Authors: Furrer Pascal , Lallemand Frédéric , Paladino Grazia Maria , Mazzone Maria Grazia , Gurny Robert
Published: June 2006

Laser assisted refractive surgery is a common procedure for the correction of visual defects. However, this technique is sometimes associated with complications such as recurrent erosion scars or late-onset corneal haze formation due to irregular wound healing. In order to improve the
risk/benefit ratio of this surgery, a better understanding of the wound healing process is absolutely necessary. The aim of the present study was to investigate in an animal model the influence of biopolymeric hydrogels in the modulation of the wound healing. Mechanical wounds were generated
in rabbit cornea with the aid of an Algerbrush burr. The closure of the wound was monitored after staining with fluorescein by means of a confocal microscope. A hydrogel based on 1% xanthan gum stimulated significantly corneal wound healing whereas other viscosified solutions or hydrogels
based on lower concentrations of xanthan gum or on hyaluronic acid did not promote wound healing.
Nanostructured Porous Silicon – Optical Properties, Surface Modification and Sensor Applications
Authors: Jelínek Ivan , Chvojka Tomáš , Vrkoslav Vladimír , Jindřich Jindřich , Lorenc Miroslav , Nižňanský Daniel , Němec Ivan , Král Vladimír , Dian Juraj
Published: June 2006

Porous silicon is a very attractive material due to its intense visible photoluminescence at room temperature. Its unique physical and chemical properties are determined by the porous structure where a nanosized silicon layer is formed during the electrochemical etching of crystalline
silicon. So far, the high chemical reactivity of the porous silicon surface has prevented its extensive application in optoelectronics. Considerable effort has been put into the development of suitable techniques of stabilization. On the other hand, high chemical reactivity and sorption capacity
of porous silicon represent the principal advantage for the construction of sensitive sensors of chemical species. This article provides a brief overview of the ongoing activities in the development of porous-silicon-based chemical sensors at the Charles University and at the Institute of
Chemical Technology. So far, the detection of chemical species is based on the measurement of the changes in photoluminescence intensity and photoluminescence decay time, other complementary electrochemical and optical detection methods will follow in order to increase the selectivity of the
detection. Another approach resulting in increased selectivity of sensor response utilizes the modification of porous silicon surface – either by physical adsorption or chemical derivatization – by various molecules with recognition properties. Due to the interdisciplinary nature
of the research the involved scientists have built a network of collaborating laboratories specialized in various fields – material research, surface chemistry, design and synthesis of the molecules with recognition properties and sensor development.
Evaluation of Confocal Fluorescence Spectroscopy for the Detection of Pathological Prion Proteins
Authors: Dietrich Anja , Bossart Karin , Oesch Bruno , Stamm Christoph , Raeber Alex J.
Published: June 2006

Prion diseases or transmissible spongiform encephalopathies (TSEs) are characterized by the accumulation in the brain of PrPSc, an abnormal isoform of the host-encoded glycoprotein PrPC. PrPSc is a reliable marker for the post mortem diagnosis of TSEs
but its use as a marker for a pre-clinical blood test has been hampered by the low levels of PrPSc in blood. We have evaluated confocal fluorescence spectroscopy (CFS) as an ultrasensitive method for the immunological detection of PrP in brain homogenates and blood serum. Using
recombinant PrP, we determined the detection limit of our CFS assay to be in the picomolar range which is in the same order of magnitude as the corresponding luminescence immunoassay (Prionics®-Check LIA). The analytical sensitivity was further investigated using brain homogenates
from BSE infected cattle that showed low levels of PrPSc by Western blot analysis. In these brain homogenates, PrPSc was detected by confocal fluorescence spectroscopy down to a dilution of 64-fold whereas the luminescence immunoassay was able to detect PrPSc
in brain homogenates diluted down to at least 128-fold suggesting that in this antibody sandwich assay the luminescence immunoassay has a higher analytical sensitivity than confocal fluorescence spectroscopy. We also demonstrated that blood serum is a suitable matrix for a confocal fluorescence
spectroscopy based TSE test, and found that serum did not interfere with the detection of spiked recombinant PrP.
Fluorescence Enhancement Detection of Underivatized Amino Acids Using a Trifluoroacetophenone-Based Tripodal Fluoroionophore
Authors: Sasaki Shin-ichi , Monma Gou , Citterio Daniel , Yamada Koji , Suzuki Koji
Published: June 2006

A tripodal fluoroionophore based on a hexasubstituted benzene unit having two trifluoroacetophenone groups and a pyrenyl moiety was synthesized, and its characteristics as fluorogenic reagent or component of an ISE or optode membrane towards several underivatized amino acids were examined.
In a solid–liquid extraction experiment in acetonitrile, the fluorescence enhancement response was observed in the order of Phe, Cys, and Gly. On the other hand, the PVC-based polymeric membrane applied in ISE showed Phe selectivity with a monoanionic Nernstian response, supporting the
assumption that the ionophore binds Phe in its anionic form. It is demonstrated that the optode membrane based on this fluoroionophore shows fluorescence enhancement response towards Phe or Cys in a flow-system.
New Opportunities for Measurement Systems Thanks to New Trends in Space Laboratories
Authors: Walther Isabelle , De Rooij Nico , Van der Schoot Bart , Cogoli Augusto
Published: June 2006

Space biology is a young discipline that is strongly evolving thanks to the development of new measuring devices. The use of instruments equipped with new sensors and new technologies gives the opportunity to follow and understand better the experiments performed. Starting about three
decades ago with relatively simple experiments aboard space laboratories like Spacelab, in the MIR station, as well as aboard biosatellites and sounding rockets, bioprocessing in space is becoming one of the interesting themes for the exploitation of the International Space Station, ISS. It
nourishes hypotheses and speculations on possible commercial and medical applications. A few pharmaceutical companies manifested their interest in joint application research programs with universities and national and international space agencies. It is believed that low-g may contribute in
two aspects to progress in this field: first, as a useful and non invasive tool to study important and still obscure biological events like signal transduction, gene expression, and cell proliferation. Second, low-g may favor the mass production of single cells by obtaining higher cell densities
per unit culture volume as well as a smooth cell–cell aggregation and three-dimensional organogenesis in the absence of sedimentation and shear forces. Technology of a high standard has to be used to obtain the best possible result in the restricted space of the ISS Laboratory. Often
new space instrumentations can trigger earth-bound development and applications.
Transport of Electronic Excitation Energy in Dye-Loaded Zeolite L
Authors: Minkowski Claudia , Calzaferri Gion
Published: June 2006

Zeolite L is an aluminosilicate with one-dimensional channels, having an opening diameter of 7.1 Å. This allows the incorporation of different, electronically non-interacting dye molecules to build an artificial photonic antenna system. The conditions within the channels are such
that the dye molecules cannot glide past each other. Hence, a consecutive incorporation leads to crystals with different compartments, where the density of one kind of dye is dominant. The photophysical processes taking place on such dye-loaded zeolite L antenna systems can be studied either
on single micrometer or submicrometer sized crystals, on crystals dispersed in a solvent, orcoated as thin layers on a support. The energy transfer process that occurs is of the Förster-type and its transfer rate can be tuned, e.g. by first incorporating the acceptor dyes, in a
second step consecutively incorporating different amounts of spacer molecules and then in a third step adding the donor dyes. By selectively exciting the donor, energy transfer to the unexcited acceptor as a function of the amount of spacer molecules can be observed. To make a quantitative
analysis, one has to take into consideration the situation at the phase boundaries of the particular compartments. This has been done by modeling the distribution of the dye molecules and empty sites within a zeolite crystal by means of a Monte Carlo simulation.
Rhenium Complexes as Highly Active Catalysts for the Hydrosilylation of Carbonyl Compounds
Authors: Huang Wenjing , Berke Heinz
Published: June 2006

[Re(PiPr3)2(NO)2]+[B(C6F5)4]? (1) and the new NO-functionalized compounds [Re(H)(PiPr3)2(NO)(NOB(C6F5)3)]
(2) and [Re(H)(NO)(NOEt)(PiPr3)2]+[B(C6F5)4]? (3) were prepared and found to be excellent catalysts for hydrosilylation of ketones. For 2 and 3 the hydrosilylation
procedures are selective, mild, and efficient, and offer very practical methodologies to prepare the respective silyloxy compounds in quantitative yields. In exemplary experiments catalyst 2 could even be recovered.
Lonza's SSP for Early Phase Delivery
Authors: Schmidt Beat
Published: June 2006

Lonza, the leading custom manufacturer of chemical intermediates and active ingredients as well as biopharmaceuticals for the pharmaceutical and agrochemical industries, has recently expanded into a new state-ofthe-art seven-storey small-scale plant (SSP) whose task is to satisfy both
clinical supply and process development with sophisticated and lean cGMP-compliant equipment. With this investment, Lonza has now closed the gap between kilo lab and launch plant in order to provide one-stop shopping for API and drug product developmentthrough-approval.
Transition Metal Catalysis for Pharmaceutical Intermediates and APIs
Authors: Indolese Adriano F. , Wasescha Domenic , Eisele Thomas , Bucher Christoph
Published: June 2006

Rohner AG, a medium-sized Swiss company, has moved from toll manufacturing of building blocks and starting materials to the custom manufacturing of intermediates and APIs for the life science industry. Therefore, Rohner AG has expanded its technology portfolio to new technologies such
as transition metal catalysis. Examples for asymmetric hydrogenation, Suzuki coupling and carbonylation are provided. In addition, the necessary changes in equipment and project management are presented and discussed.
BPMSS – Lonza's Biopharmaceutical Small Scale Plant Started cGMP Manufacturing in September 2004
Authors: Hoeks Frans W.J.M.M. , Schmidhalter Diego R. , Gloeckler Rainer , Herwig Christoph , Theriault Karen , Frie Sven , Van den Broek Wouter , Laukel Frank
Published: June 2006

In September 2004 Lonza (Visp, Switzerland) started operations in a new state of the art facility for cGMP manufacture of injectable grade microbially derived biopharmaceuticals. Both intracellular and secreted products can be processed in the new production line, which delivers bulk
drug substances. cGMP conformity, including clean room classification, was cross-checked during the design phase with the Swiss regulatory authorities. The layout of the highly automated multi-product line is based on a high performance 1000 l bioreactor suitable for high cell density fermentation.
Besides standard chromatography and ultrafiltration, the ex-proof design in upstream and downstream areas allows for solvent feeds in fermentation and for implementation of HPLC purification steps in protein and peptide purification.
Ion-Imprinted Polymer Concept for Selective Extraction of 90Y and 152Eu for Medical Applications and Nuclear Power Plant Monitoring
Authors: Froidevaux Pascal , Happel Steffen , Chauvin Anne-Sophie
Published: June 2006

The metal ion imprinted concept has been used to imprint dipicolinic derivative coordination cages in styrene-based polymeric material. This resin displays very high selectivity for yttrium and lanthanides. Distribution coefficients determined for 88Y and 85Sr
emphasize the possibility for the material to be used as chromatographic support for direct production of medical grade 90Y from a 90Sr source. Europium has been successfully extracted by the resin from a large volume of tap water. Thus the material could be used for
radiation monitoring of nuclear power plants, particularly regarding the determination of radiolanthanides in the cooling system.
Mitochondrial Toxicity of Drugs
Authors: Todesco Liliane , Waldhauser Katri , Krähenbühl Stephan
Published: June 2006

Mitochondria are important targets of drug toxicity. A variety of drugs has been shown to affect the electron transport chain, coupling of oxidative phosphorylation, ?-oxidation or other mitochondrial functions. Such damaging events may lead to the opening of a large pore across
the mitochondrial membranes – the membrane permeability transition pore – eventually leading to apoptosis or necrosis of cells, depending on the cellular ATP content. Such drugs may therefore lead to organ damage, particularly in the liver, kidney, heart or skeletal muscle.
A Thorough Training in Modern Drug Design
Authors: Vedani Angelo , Schwardt Oliver , Rabbani Said , Ernst Beat
Published: June 2006

The laboratory class Modern Drug Design at the Department of Pharmacy of the University of Basel offers the students a thorough training in modern drug design. First, antagonists for the Bradykinin B2 receptor are designed using state-of-the-art modelling techniques,
followed by solid-phase synthesis of the most potent candidates identified in silico. Thereafter, their activity is determined by a fluorometric assay. By communicating the results to the next class of students, a feedback loop is completed, thereby allowing the design strategy to be
improved.
Albert Hofmann's Pioneering Work on Ergot Alkaloids and Its Impact on the Search of Novel Drugs at Sandoz, a Predecessor Company of Novartis: Dedicated to Dr. Albert Hofmann on the occasion of his 100th birthday
Authors: Giger Rudolf K.A. , Engel Günter
Published: June 2006

The scientific research on ergot alkaloids is fundamentally related to the work of Dr. Albert Hofmann, who was able to produce, from 1935 onwards, a number of novel and valuable drugs, some of which are still in use today. The complex chemical structures of ergot peptide alkaloids and
their pluripotent pharmacological activity were a great challenge for Dr. Hofmann and his associates who sought to unravel the secrets of the ergot peptide alkaloids; a source of inspiration for the design of novel, selective and valuable medicines.
Targeted Approaches in Natural Product Lead Discovery
Authors: Potterat Olivier
Published: June 2006

Natural products still constitute a prolific source of lead compounds for the development of novel drugs. Due to their unmatched structural diversity they represent an indispensable complement to synthetic compound collections and virtual libraries. However, the tremendous changes which
have taken place in the drug discovery process over the last decade have introduced completely new requirements for natural product research. The classical bioactivity-guided approach no longer matches the timelines and the workflow of modern drug discovery. More targeted approaches are needed
in order to identify promising candidate molecules at an early stage, and to accelerate the follow-up process. We describe herein our strategy for tracking bioactive components in complex mixtures, and discuss the potential of accurate mass measurements for natural product identification and
the impact of mass-controlled preparative HPLC on the isolation process of bioactive compounds.
Synthesis of Amphiphilic Copolymers of Poly(ethylene oxide) and Poly(ϵ‐caprolactone) with Different Architectures, and Their Role in the Preparation of Stealthy Nanoparticles
Authors: Rieger J. , Passirani C. , Benoit J.‐P. , Van Butsele K. , Jérôme R. , Jérôme C.
Published: June 2006

Well‐defined copolymers of biocompatible poly(ϵ‐caprolactone) (PCL) and poly(ethylene oxide) (PEO) are synthesized by two methods. Graft copolymers with a gradient structure are prepared by ring‐opening copolymerization of ϵ‐caprolactone (ϵCL) with a PEO macromonomer of the ϵCL‐type. The ϵCL polymerization is initiated by a PEO macroinitiator to prepare diblock copolymers. These amphiphilic copolymers are used as stabilizers for biodegradable poly(D,L‐lactide) (PLA) nanoparticles prepared by a nanoprecipitation technique. The effect of the copolymer characteristic features (architecture, composition, and amount) on the nanoparticle formation and structure is investigated. The average size, size distribution, and stability of aqueous suspensions of the nanoparticles is measured by dynamic light scattering. For comparison, an amphiphilic random copolymer, poly(methyl methacrylate‐co‐methacrylic acid) (P(MMA‐co‐MA)), is synthesized. The stealthiness of the nanoparticles is analyzed in relation to the copolymer used as stabilizer. For this purpose, the activation of the complement system by nanoparticles is investigated in vitro using human serum. This activation is much less important whenever the nanoparticles are stabilized by a PEO‐containing copolymer rather than by the P(MMA‐co‐MA) amphiphile. The graft copolymers with a gradient structure and the diblock copolymers with similar macromolecular characteristics (molecular weight and hydrophilicity) are compared on the basis of their capacity to coat PLA nanoparticles and to make them stealthy.
Red Phosphorescent Iridium Complex Containing Carbazole‐Functionalized β‐Diketonate for Highly Efficient Nondoped Organic Light‐Emitting Diodes
Authors: Liu Z. W. , Guan M. , Bian Z. Q. , Nie D. B. , Gong Z. L. , Li Z. B. , Huang C. H.
Published: June 2006

A novel red phosphorescent iridium complex containing a carbazole‐functionalized β‐diketonate, Ir(DBQ)2(CBDK) (bis(dibenzo[f,h]quinoxalinato‐N,C2) iridium (1‐(carbazol‐9‐yl)‐5,5‐dimethylhexane‐2,4‐diketonate)) is designed, synthesized, and characterized. The electrophosphorescence properties of a nondoped device using the title complex as an emitter with a device configuration of indium tin oxide (ITO)/N,N′‐diphenyl‐N,N′‐bis(1‐naphthyl)‐1,1′‐diphenyl‐4,4′‐diamine (NPB; 20 nm)/iridium complex (20 nm)/2,9‐dimethyl‐4,7‐diphenyl‐1,10‐phenanthroline (BCP; 5 nm)/tris(8‐hydroxyquinoline) (AlQ; 30 nm)/Mg0.9Ag0.1 (200 nm)/Ag (80 nm) are examined. The results show that the nondoped device achieves a maximum lumen efficiency as high as 3.49 lm W–1. To understand this excellent result observed, two reference complexes Ir(DBQ)2(acac), where acac is the acetyl acetonate anion, and Ir(DBQ)2(FBDK), [bis(dibenzo[f,h]quinoxalinato‐N,C2) iridium (1‐(9‐methyl‐fluoren‐9‐yl)‐6,6‐dimethylheptane‐3,5‐diketonate)], have also been synthesized, and as emitters they were examined under the same device configuration. The maximum lumen efficiency of the former compound is found to be 0.26 lm W–1 while that for the latter is 0.37 lm W–1, suggesting that the excellent performance of Ir(DBQ)2(CBDK) can be attributed mainly to an improved hole‐transporting property that benefits the exciton transport. In addition, a bulky diketonate group separates the emitter centers from each other, which is also important for organic light‐emitting diodes.
Oxidative carbonylation of phenol to diphenyl carbonate catalyzed by palladium complexes bridged with N,N‐ligands over functionalized silica
Authors: Fan Guo‐zhi , Li Tao , Li Guang‐xing
Published: June 2006

Heterogeneous palladium catalysts anchored on functionalized silica were prepared by sol–gel methods and their catalytic properties for the oxidative carbonylation of phenol to diphenyl carbonate (DPC) were investigated. The catalysts were characterized by means of IR, XPS, EA and BET. The Pd loading in the heterogeneous catalysts and leaching in solution were detected by atomic absorption. The effects of different reaction parameters such as temperature, solvent and inorganic cocatalyst on the yield of DPC and Pd leaching were also studied. It was found that Cu2O and tetrahydrofuran (THF) were the best partners with these heterogeneous catalysts. In the presence of 3 Å molecular sieves as dehydrating agent, the heterogeneous palladium catalyst prepared from 2‐acylpyridine revealed excellent catalytic performance and stability at 110 °C for 5 h, giving 13.7% yield of DPC based on phenol and 4.0% Pd loss in solution. The heterogeneous catalyst was more active and stable compared with traditional supported PdC catalyst under the same reaction conditions. Copyright © 2005 John Wiley & Sons, Ltd.
Superior real time method to evaluate photo‐curing resin by means of rigid‐body pendulum rheometer
Authors: Chiu Hsien‐Tang , Cheng Ming‐Feng
Published: June 2006

The objective of this article is to establish a new method in evaluating photo‐polymerization resin reaction behavior, and to use the trends resulting from past evaluation methods and those already known to prove the feasibility of this method. Another objective is to compare the data gathered using the differential photo calorimeter (DPC) method and RPT on different photo‐polymerization resin systems to illustrate that the application of RPT on photo‐polymerization resin studies is more suitable. Experiment results show that the trends through the real time method using oxide series acrylate research through rigid‐body Pendulum Rheometer, the photo‐curing behavior under the various parameters of monomer functionality, and photo‐initiator concentration can all be observed. Comparing the DPC and RPT methods on polyester acrylate series, when the oligomer of tetra‐functional polyester acrylate is added with a different ratio of the monomer of propoxylated neopentyl‐glycol di‐acrylate, DPC evaluation methods show that the differences in observation are minimal. However, when RPT was applied, not only were the differences in reaction speed observed, but also the differences in crosslinking and other data in the hardening process when the balanced time was achieved during the oscillations procedure. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 3402–3407, 2006
Fine characterization of plasma‐polymerized films from a methane/air mixture
Authors: Mori Masaru , Izumi Hirokazu , Nakagawa Kazuharu , Nakamoto Tsuyoshi , Mori Takeshi , Kawashimo Yasushi , Ueda Yasukiyo
Published: June 2006

The plasma polymerization of methane/air mixtures was performed to produce a hydrophilic film on a substrate, and the obtained films were characterized with ellipsometry, elemental analysis, Fourier transform infrared spectroscopy, X‐ray photoelectron spectroscopy, atomic force microscopy, and contact‐angle measurements. Fourier transform infrared revealed that the structure of the plasma‐polymerized films changed with increasing film thickness; that is, an increase in the film thickness led to an increase in the absorbance ratio of the carbonyl band at 1664 cm−1 to the methyl band at 1385 cm−1. Although the contents of nitrogen and oxygen measured by elemental analysis changed with the film thickness, the contact angle and X‐ray photoelectron spectroscopy atomic ratio of the films were independent of it. Nitrogen and oxygen were contained in the bulk more than on the surface of the films. Nitrogen and oxygen were copolymerized with methane, and the properties of the obtained films were similar to those of an amide compound. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 3408–3414, 2006
Synthesis and characterization of hyperbranched poly(silyl ester)s
Authors: Han Nianfeng , Liu Zonglin , Jin Liqiang
Published: June 2006

Hyperbranched poly(silyl ester)s were synthesized via the A2 + B4 route by the polycondensation reaction. The solid poly(silyl ester) was obtained by the reaction of di‐tert‐butyl adipate and 1,3‐tetramethyl‐1,3‐bis‐β(methyl‐dicholorosilyl)ethyl disiloxane. The oligomers with tert‐butyl terminal groups were obtained via the A2 + B2 route by the reaction of 1,5‐dichloro‐1,1,5,5‐tetramethyl‐3,3‐diphenyl‐trisi1oxane with excess amount of di‐tert‐butyl adipate. The viscous fluid and soft solid poly(silyl ester)s were obtained by the reaction of the oligomers as big monomers with 1,3‐tetramethyl‐1,3‐bis‐β(methyl‐dicholorosilyl)ethyl disiloxane. The polymers were characterized by 1H NMR, IR, and UV spectroscopies, differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA). The 1H NMR and IR analysis proved the existence of the branched structures in the polymers. The glass transition temperatures (Tg's) of the viscous fluid and soft solid polymers were below room temperature. The Tg of the solid poly(silyl ester) was not found below room temperature but a temperature for the transition in the liquid crystalline phase was found at 42°C. Thermal decomposition of the soft solid and solid poly(silyl ester)s started at about 130°C and for the others it started at about 200°C. The obtained hyperbranched polymers did not decompose completely at 700°C. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 3430–3436, 2006
A rheology study of high‐energy radiolysis of a semicrystalline ethylene‐propylene copolymer containing DOP mobilizer
Authors: Fuzail Mohammad , Hill David J. T. , Park Yoosup , Halley Peter
Published: June 2006

The radiolysis of a poly(ethylene‐co‐propylene), Elpro grade P 750 J, marketed by Thai Polypropylene Co. Ltd. for the manufacture of medical goods, was investigated at ambient temperature and melt rheology measured. The roles of calcium stearate, blended with the Elpro as a processing aid, and dioctyl phthalate (DOP), added in various amounts as a radical scavenger, were assessed. Following radiolysis, G′ and the viscosity of the polymer melts at 453 K both decreased with increasing radiation dose, even when the mobilizer was present. The results indicated that although the DOP did scavenge radicals, it did not protect the polymer from net chain scission in a low‐dose regimen. The value of (GS − 4GX) was approximately 0.6–0.7. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 3437–3441, 2006
Hydroxyalkylation of barbituric acid. I. Hydroxymethyl derivatives of barbituric acid—Precursors of polyetherols with a pyrimidine ring
Authors: Ślączka Anna , Lubczak Jacek
Published: June 2006

The reaction of barbituric acid with formaldehyde at variable molar ratios was studied. The structure of the products was elucidated using 1H‐NMR and IR spectroscopy as well as acidic number and formaldehyde percentage analysis. The products were potential substrates for the synthesis of linear and multifunctional polyetherols with a pyrimidine ring by reaction with oxiranes. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101:3468–3478, 2006
Synthesis and Antiviral Evaluation of Novel Cyclopropyl Nucleosides, Phosphonate Nucleosides and Phosphonic Acid Nucleosides
Authors: Hyun Oh Chang , Hong Joon Hee
Published: June 2006

Novel phenyl‐branched cyclopropyl nucleosides, phosphonates, and phosphonic acid analogues were designed and synthesized as potential antiviral agents. Coupling of the mesylate 10 with natural bases (U, T, C, A) and desilylation/hydrolysis afforded a series of novel cyclopropyl nucleosides 15–18. Phosphonate and phosphonic acid nucleosides 22–29 were also readily synthesized from the mesylate 21. The synthesized compounds were evaluated for their antiviral activity against various viruses such as HIV‐1, HSV‐1, HSV‐2, and HCMV.
Synthesis and Molluscicidal Activity of New Cinnoline and Pyrano [2,3‐c]pyrazole Derivatives
Authors: Abdelrazek Fathy M. , Metz Peter , Metwally Nadia H. , El‐Mahrouky Sherif F.
Published: June 2006

2‐(3‐Hydroxy‐5,5‐dimethylcyclohexylidene)malononitrile 5 undergoes an azo coupling reaction with aryldiazonium salts to afford 3‐amino‐2‐aryl‐6,6‐dimethyl‐8‐oxo‐2,6,7,8‐tetrahydrocinnoline‐4‐carbonitriles 7. Upon reflux in acetic acid, these compounds were acetylated to give the cinnoline derivatives 9. The pyrazolones 10a, b react with 3‐furfurylidene‐ and 3‐thienylidene‐malononitrile derivatives 11a, b to afford the pyrano[2,3‐c]pyrazole derivatives 13a–d. These newly synthesized compounds show generally a moderate molluscicidal activity to Biomphalaria alexandrina snails.
The effect of discordance among violence and general recidivism risk estimates on predictive accuracy
Authors: Mills Jeremy F. , Kroner Daryl G.
Published: June 2006

Introduction Previous research has shown that the prediction of short‐term inpatient violence is negatively affected when clinicians' inter‐rater agreement is low and when confidence in the estimate of risk is low. This study examined the effect of discordance between risk assessment instruments used to predict long‐term general and violence risk in offenders.

Methods The Psychopathy Checklist – Revised (PCL–R), Level of Service Inventory – Revised (LSI–R), Violence Risk Appraisal Guide (VRAG), and the General Statistical Information on Recidivism (GSIR) were the four risk‐prediction instruments used to predict post‐release general and violent recidivism within a sample of 209 offenders.

Results The findings lend empirical support to the assumption that predictive accuracy is threatened where there is discordance between risk estimates. Discordance between instruments had the impact of reducing predictive accuracy for all instruments except the GSIR. Further, the influence of discordance was shown to be greater on certain instruments over others. Discordance had a moderating effect on both the PCL–R and LSI–R but not on the VRAG and GSIR.

Conclusions There is a distinct advantage when attempting to predict recidivism to employing measures such as the LSI‐R, which includes dynamic variables and intervention‐related criminogenic domains, over a measure purely of fixed characteristics, such as the GSIR; however, if there is discordance between the risk estimates, caution should be exercised and more reliance on the more static historically based instrument may be indicated. Copyright © 2006 John Wiley & Sons, Ltd.
Active Site Comparison of CoII Blue and Green Nitrite Reductases
Authors: Sato Katsuko , Dennison Christopher
Published: June 2006

Copper‐containing nitrite reductases (NiRs) possess type 1 (T1) and type 2 (T2) copper sites and can be either green or blue in color owing to differences at their T1 centers. The active sites of a green and a blue NiR were studied by utilizing their T1CuI/T2CoII and T1CoII/T2CoII‐substituted forms. The UV/Vis spectra of these derivatives highlight the similarity of the T2 centers in these enzymes and that T1 site differences are also present in the CoII forms. The paramagnetic NMR spectra of T1CuI/T2CoII enzymes allow hyperfine shifted resonances from the three T2 His ligands to be assigned: these exhibit remarkably similar positions in the spectra of both NiRs, emphasizing the homology of the T2 centers. The addition of nitrite results in subtle alterations in the paramagnetic NMR spectra of the T1CuI/T2CoII forms at pH<7, which indicate a geometry change upon the binding of substrate. Shifted resonances from all of the T1 site ligands have been assigned and the CoIIN(His) interactions are alike, whereas the CβH proton resonances of the Cys ligand exhibit subtle chemical shift differences in the blue and green NiRs. The strength of the axial CoIIS(Met) interaction is similar in the two NiRs studied, but the altered conformation of the side chain of this ligand results in a dramatically different chemical shift pattern for the CγH protons. This indicates an alteration in the bonding of the axial ligand in these derivatives, which could be influential in the CuII proteins.
Synthesis of Extended Triphenylenes by Palladium‐Catalyzed [2+2+2] Cycloaddition of Triphenylynes
Authors: Romero Carmen , Peña Diego , Pérez Dolores , Guitián Enrique
Published: June 2006

The synthesis of ortho‐(trimethylsilyl)triphenylenyl triflates 7 is described. Fluoride‐induced decomposition of these triflates leads to the generation of didehydrotriphenylenes (triphenylynes) 6. These arynes undergo [4+2] cycloadditions with dienes to afford the corresponding Diels–Alder adducts or palladium‐catalyzed formal [2+2+2] cycloadditions to afford extended triphenylenes.
Chiral Poly(ureidophthalimide) Foldamers in Water
Authors: Sinkeldam Renatus W. , van Houtem Michel H. C. J. , Pieterse Koen , Vekemans Jef A. J. M. , Meijer E. W.
Published: June 2006

Poly(ureidophthalimide)s decorated with hydrophilic side chains, that ensure solubility in aqueous media, have been synthesized and characterized by UV/Vis and circular dichroism (CD) spectroscopy. Temperature and concentration dependent CD measurements in water have revealed an almost temperature and concentration independent Cotton effect, indicative for a strong intramolecular organization. Similar studies in THF demonstrate the dynamic nature of the secondary architecture, a characteristic of foldamers. In addition, the bisignated Cotton effect in water is opposite in sign to that in THF, suggestive for a solvent‐dependent preference for one helical handedness. Mixing experiments prove the dominance of water in determining the handedness of the helical architecture. The solvent allows for control over the helical architecture and thus governs the supramolecular synthesis.
Ligand Variations in [ReX(diimine)(CO)3] Complexes: Effects on Photocatalytic CO2 Reduction
Authors: Kurz Philipp , Probst Benjamin , Spingler Bernhard , Alberto Roger
Published: June 2006

Two series of complexes [MX(diimine)(CO)3] (M = Tc, Re) have been prepared, fully characterised and investigated for their ability to act as photocatalysts for the reduction of CO2 to CO. One series consists of complexes with different aromatic diimine ligands while keeping X = Br– constant. The second series describes complexes with diimine = 2,2‐bipyridine and variations in the anionic ligand X–. Although numerous complexes of this type have been prepared and investigated before, a systematic study of their photocatalytic activity has not yet been carried out. Electrochemical and spectroscopic characterisation of these complexes has been performed with the objective of better understanding their respective activity in the photocatalytic CO2 reduction.Despite various modifications, catalytic activity is retainedfor all compounds exhibiting fluorescence, including [99TcCl(bipy)(CO)3], whereas nonfluorescing compounds did not convert CO2 to CO. The correlation of catalytic activity and spectroscopic or electrochemical properties such as absorption or emission wavelengths, redox potentials or Stern–Volmer constants for the reductive quenching of the excited complexes is difficult. Nevertheless, the study emphasises the possibility to obtain [ReX(CO)3(diimine)] complexes with a wide range of physicochemical properties by ligand variations and the great potential of compounds of this class of complexes as inorganic photosensitisers. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Platinum Complexes with One Monodentate Ligand (1‐Methylbenzimidazole or Antiviral Ribavirin) Flanked by Two cis‐NMe2 Groups: Informative Models for Assessing Interligand Interactions
Authors: Cerasino Leonardo , Natile Giovanni
Published: June 2006

Platinum complexes with a tridentate amine ligand (A3) and a nucleobase (L) represent very useful models for investigating nucleobase/cis‐amine interactions without the complications arising from nucleobase/nucleobase interferences present in the more frequently used cis‐A2PtL2 model systems (A2 = two monodentate amines or a diamine). In this context, the Me3dienPtL complexes (Me3dien = N1,N4,N7‐trimethyldiethylenetriamine), previously investigated, were particularly informative. The presence of a methyl group on each terminal nitrogen atom renders the rotation of L about the Pt–L bond slow on the NMR timescale and the two half spaces defined by the coordination plane inequivalent. Thus, guanine and deoxyguanine derivatives were found to have comparable rates of rotation by way of a H‐bond interaction between the O6 atom of the rotating guanine and the NH group of the cis‐amine. We have now extended the investigation to Me5dien complexes (Me5dien = N1,N1′,N4,N7,N7′‐pentamethyldiethylenetriamine). The results indicate that the absence of a proton on the terminal nitrogen atoms not only reduces the rate of rotation of L by a factor of 1010, but also dramatically increases the difference in the rates between the L ligands mimicking guanine and deoxyguanine. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Controlling the Size of BaF2 Nanocubes from 1000 to 10 nm
Authors: Gao Peng , Xie Yi , Li Zhen
Published: June 2006

Size control of BaF2 nanocubes has been achieved by varying reaction time and pH value, thus producing nanocubes with a controllable edge length in the range 10–1000 nm. A linear relationship between cube size and reaction time has been revealed. Furthermore, a process has been developed to separate the growing BaF2 nanocubes from the remaining solid products at different stages of the synthesis. On the basis of the observed crystallite morphologies, we have elucidated an “extension growing” mechanism to describe the size‐controlled growth of BaF2 nanocubes using this method. Photoluminescence results demonstrate that the deoxidant selenite ions prevent the incorporation of oxygen into the BaF2 nanocubes effectually, which will greatly affect their performance as scintillators. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Thin Film Microelectrodes in SOFC Electrode Research
Authors: Fleig J. , Baumann F. S. , Brichzin V. , Kim H.‐R. , Jamnik J. , Cristiani G. , Habermeier H.‐U. , Maier J.
Published: June 2006

Experimental studies using conventional (porous) solid oxide fuel cell (SOFC) electrodes are often rather difficult to interpret in terms of a mechanistic understanding of the electrochemical polarization phenomena. Owing to the complex morphology and structure of porous electrodes, a quantitative determination of the properties of the electrochemical materials rather than of the effective electrode properties is far from being straightforward. Micro‐patterned epitaxially grown thin film electrodes offer new possibilities in this field of research. This is particularly true for microelectrodes of several 10 μm diameter, fabricated lithographically from thin films. They allow well‐defined geometry‐dependent experiments, minimize the importance of ohmic drops, and avoid the necessity of a reference electrode. Further, they turn out to be particularly well‐suited for statistical studies, as well as for the investigation of irreversible processes. Hence, thin‐film microelectrodes are an excellent tool for the investigation of SOFC electrode materials. This is exemplified by p(O2)‐, voltage‐, and geometry‐dependent measurements on (La0.8Sr0.2)0.92MnO3 and La0.6Sr0.4Co0.8Fe0.2O3–δ microelectrodes on single‐crystal yttria‐stabilized zirconia electrolytes.
Vaporization and Diffusion Studies on the Stability of Doped Lanthanum Gallates
Authors: Stanislowski M. , Peck D.‐H. , Woo S.‐K. , Singheiser L. , Hilpert K. , Schulz O. , Martin M.
Published: June 2006

Vaporization and diffusion determine the stability of doped lanthanum gallates under SOFC operating conditions. Systematic vaporization studies of Ga and other elements were carried out using the vapor transpiration method. It was shown that the Ga vaporization is controlled by diffusion from the bulk to the surface. Diffusion coefficientsDGaand vaporization coefficients αGawere determined by fitting the measured vaporization data to a vaporization model. Secondary phases formed as a result of the vaporization were detected. The influence of different doping levels of Sr, Mg and Fe on the Ga vaporization was elucidated. Moreover, cation self‐diffusion of139La,84Sr and25Mg as well as cation impurity diffusion of144Nd,89Y and56Fe in polycrystalline samples of doped lanthanum gallate were directly determined for the composition La0.9Sr0.1Ga0.9Mg0.1O2.9as an example, from diffusion profiles determined by SIMS. It was found that diffusion occurs by means of bulk and grain boundaries. The bulk diffusion coefficients are similar for all cations with activation energies which are strongly dependent on temperature. The results are explained by a frozen‐in defect structure at low temperatures in the ABO3perovskite lattice and by proposing a defect cluster containing cation vacancies in the A and B sublattices, as well as oxygen vacancies.
Carbonyl Tailored Electrocatalysts
Authors: Alonso‐Vante N.
Published: June 2006

In recent years, a number of carbonyl clusters have been used as precursors to synthesize electrocatalysts of the nanolength scale for fuel cell reactions. This short review aims to delineate the concepts underlying the synthesis of these type of materials, highlighting the rationale of this type of research. Some selected examples regarding fuel cell reactions at the anode and the cathode are discussed.
Bone marrow and tumour stroma: an intimate relationship
Authors: Direkze Natalie C , Alison Malcolm R
Published: June 2006

In recent years the bone marrow has become recognized as a potential source of cells for non‐haematopoietic wound healing, in some instances demonstrating surprising plasticity in providing new epithelial cells. On the other hand, the contribution of bone marrow derived cells to fibrosis and blood vessel formation is more widely acknowledged. Tumour stroma has a vital role to play in determining cancer growth and spread, and there is a growing realization that the bone marrow has a significant input into this desmoplastic response. This review focuses on the contribution of bone marrow cells to tumour stroma, highlighting the bone marrow as a potential new portal through which to direct anti‐tumour therapies. Copyright © 2006 John Wiley & Sons, Ltd.