bluuebunny/crossref_metadata_2025 huggingface dataset:
A Convenient Synthetic Route for the Preparation of Nonsymmetric Metallo‐salphen Complexes
Authors: Kleij Arjan W. , Tooke Duncan M. , Spek Anthony L. , Reek Joost N. H.
Published: October 2005

New nonsymmetric metallo(II)‐salphen complexes 1–6 [salphen = N,N′‐bis(salicylidene)‐1,2‐diaminobenzene, M = Zn, Ni] have been prepared in high yield by a templated, one‐pot two‐step procedure starting from substituted ortho‐phenylenediamines, salicylaldehydes and metal acetates in MeOH under mild conditions. The procedure allows the introduction of functional groups in the bridging phenyl fragment, whereas the use of the substituted monoimine intermediates 7–10 results in complexes with two structurally different phenyl side groups with various functionalities (complexes 11–21) upon reaction with a second, different, salicylaldehyde reagent. A range of analytical tools confirmed the structures of these nonsymmetric salphen derivatives and the X‐ray molecular structure of one of these nonsymmetric ZnII‐salphen complexes (i. e., 4) is also reported. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Chemiluminescence of Electrochemically Oxidized 9‐(Phenylthiophosphoryloxymethylidene)‐10‐methylacridan Derivatives
Authors: Mirkhalaf Fakhradin , Wilson Robert
Published: October 2005

The electrochemistry and electrochemiluminescence (ECL) properties of acridan phosphate ester are reported. Electrochemical oxidation of 9‐(phenylthiophosphoryloxymethylidene)‐10‐methylacridan disodium salt (Compound 1) yields the corresponding acridinium ester. The latter undergoes a fast reaction with hydrogen peroxide forming an intermediate, which produces electronically excited 9‐methyl acridone and emits blue light after relaxation to the ground state. The electrochemical oxidation of this compound appears to occur in two one‐electron steps and light emission is observed for both steps. The chemiluminescence reaction could also be triggered by electrochemical oxidation of Compound 1 in the absence of H2O2 when the solution was saturated with O2. Mechanisms for these reactions based on ECL, voltammetry and in situ UV‐vis identification of the oxidation products are proposed. Due to the low electrode potential required to achieve ECL emission and the occurrence of light emission in the absence of hydrogen peroxide, this compound is proposed as a label for rapid and sensitive determination of biomolecules in automated analysis.
Evolution of the morphological innovations of feathers
Authors: Prum Richard O.
Published: October 2005

Feathers are complex assemblages of multiple morphological innovations. Recent research on the development and evolution of feathers has produced new insights into the origin and diversification of the morphological innovations in feathers. In this article, I review and discuss the contribution of three different factors to the evolution of morphological innovations in feathers: feather tubularity, hierarchical morphological modularity, and the co‐option molecular signaling modules. The developing feather germ is a tube of epidermis with a central dermal pulp. The tubular organization of the feather germ and follicle produces multiple axes over which morphological differentiation can be organized. Feather complexity is organized into a hierarchy of morphological modules. These morphological modules evolved through the innovative differentiation along multiple different morphological axes created by the tubular feather germ. Concurrently, many of the morphological innovations of feathers evolved through the evolutionary co‐option of plesiomorphic molecular signaling modules. Gene co‐option also reveals a role for contingency in the evolution of hierarchical morphological innovations. J. Exp. Zool. (Mol. Dev. Evol.) 304B, 2005. © 2005 Wiley‐Liss, Inc.
Surface‐Initiated Atom Transfer Radical Polymerization on Poly(Vinylidene Fluoride) Membrane for Antibacterial Ability
Authors: Zhai Guangqun , Shi Zhi L. , Kang En T. , Neoh Koon G.
Published: October 2005

Summary: Surface‐active microporous membranes were prepared from the poly(vinylidene fluoride)‐graft‐poly(2‐(2‐bromoisobutyryloxy)ethyl acrylate) copolymer (PVDF‐g‐PBIEA copolymer) by phase inversion in water. The PBIEA side chains could function as initiators for the atom transfer radical polymerization (ATRP) of 2‐(N,N‐dimethylamino)ethyl methacrylate on the membrane surfaces to give rise to the PVDF‐g‐PBIEA‐ar‐PDMAEMA membranes. N‐alkylation with hexyl bromide and nitromethane gave rise to the quanternized PVDF‐g‐PBIEA‐ar‐QPDMAEMA membranes with polycation chains chemically tethered on the membrane surface, including the pore surfaces. The changes in the surface morphology and the surface chemical composition were confirmed by scanning electron microscopy and X‐ray photoelectron spectroscopy. The scanning electron microscopy revealed that, in comparison to the pristine PVDF‐g‐PBIEA membranes, not only could the PVDF‐g‐PBIEA‐ar‐QPDMAEMA membranes remove the Gram‐negative bacterium Escherichia coli but also inhibited the bacterial reproduction on the membranes to a significant extent.

PVDF‐g‐PBIEA and PVDF‐g‐PBIEA‐ar‐QPDMAEMA membranes after exposure to water‐borne E. coli suspension for 24 h.

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PVDF‐g‐PBIEA and PVDF‐g‐PBIEA‐ar‐QPDMAEMA membranes after exposure to water‐borne E. coli suspension for 24 h.
Hydroxypropyl Chitosan Bearing β‐Cyclodextrin Cavities: Synthesis and Slow Release of its Inclusion Complex with a Model Hydrophobic Drug
Authors: Prabaharan Mani , Mano João F.
Published: October 2005

Summary: Hydroxypropyl chitosan‐graft‐carboxymethyl β‐cyclodextrin (HPCH‐g‐CM β‐CD) was synthesized by grafting CM β‐CD onto HPCH using water soluble 1‐ethyl‐3‐(3‐dimethylaminopropyl)carbodiimide (EDC) as the condensing agent. Due to the presence of hydrophobic β‐CD rings onto the HPCH backbone, this polymer can be used as a matrix for controlled drug release. The adsorption of a hydrophobic model drug, ketoprofen, by HPCH‐g‐CM β‐CD microparticles (using tripolyphosphate as an ionic crosslinking agent) fitted well in the Langmuir isotherm equation. The drug dissolution profile showed that HPCH‐g‐CM β‐CD microparticles provided a slower release of the entrapped ketoprofen than chitosan, and the release behavior was influenced by the pH value of the medium. These results suggest that β‐CD grafted with chitosan derivatives may become a potential biodegradable delivery system to control the release of hydrophobic drugs with pH‐responsive capability.

The structure and drug release profiles of HPCH‐g‐CM β‐CD.

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The structure and drug release profiles of HPCH‐g‐CM β‐CD.
Novel Hydrogel Membrane Based on Copoly(hydroxyethyl methacrylate/p‐vinylbenzyl‐poly(ethylene oxide)) for Biomedical Applications: Properties and Drug Release Characteristics
Authors: Arıca M. Yakup , Bayramoǧlu Gülay , Arıca Betül , Yalçın Emine , Ito Koichi , Yagci Yusuf
Published: October 2005

Summary: The aim of this study was to synthesize and characterize a novel biocompatible polymeric membrane system and demonstrate its potential use in various biomedical applications. Synthetic hydrogels based on poly(hydroxyethyl methacrylate), poly(HEMA), have been widely studied and used in biomedical fields. A novel copolymer hydrogel was prepared in the membrane form using 2‐hydroxyethyl methacrylate monomer (HEMA) and a macromonomer p‐vinylbenzyl‐poly(ethylene oxide) (V‐PEO) via photoinitiated polymerization. A series of poly(HEMA/V‐PEO) copolymer membranes with different compositions was prepared. The membranes were characterized using infrared, thermal and SEM analysis. The thermal stabilities of the copolymer membranes were found to be lowered by an increase in the ratio of macromonomer (V‐PEO) in the membrane structure. Because of the incorporation of PEO segments, the copolymers exhibited significantly higher hydrophilic surface properties than pure poly(HEMA), as demonstrated by contact angle measurements. Equilibrium swelling studies were conducted to investigate the swelling behavior of the membranes. The equilibrium water uptake was reached in about 4 h. Moreover, the blood protein adsorption and platelet adhesion were significantly reduced on the surface of the PEO containing copolymer membranes compared to control pure poly(HEMA). Drug release experiments were performed in a continuous release system using model drug (vancomycin) loaded copoly(HEMA/V‐PEO) membranes. A specific poly(HEMA/V‐PEO) membrane formulation possessing the highest PEO content (with a HEMA:V‐PEO (mmol:mmol) feed ratio of 112:1 and loaded with 40 mg antibiotic/g polymer) released about 81% of the total loaded drug in 24 h at pH 7.4. This membrane composition provided the best results and can be considered as a potential candidate for a transdermal antibiotic carrier and various biomedical and biotechnological applications.

DSC measurements of membranes.

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DSC measurements of membranes.
Microspheres Made of Poly(ε‐caprolactone)‐Based Amphiphilic Copolymers: Potential in Sustained Delivery of Proteins
Authors: Quaglia Fabiana , Ostacolo Luisanna , Nese Giuseppe , De Rosa Giuseppe , La Rotonda Maria Immacolata , Palumbo Rosario , Maglio Giovanni
Published: October 2005

Summary: Microspheres of amphiphilic multi‐block poly(ester‐ether)s (PEE)s and poly(ester‐ether‐amide)s (PEEA)s based on poly(ε‐caprolactone) (PCL) were investigated as delivery systems for proteins. The interest was mainly focused on the effect of their molecular structure and composition on the overall properties of the microspheres, encapsulating bovine serum albumin (BSA) as a model protein. PEEs and PEEAs were prepared using a α,ω‐dihydroxy‐terminated PCL macromer ($\overline M _{\rm n}$ = 2.0 kDa) as a hydrophobic component. Hydrophilic oxyethylene sequences were generated using poly(ethylene oxide)s (PEO)s of different molecular mass ($\overline M _{\rm n}$ = 300–600 Da) in the case of PEEs, or 4,7,10‐trioxa‐1,13‐tridecanediamine (Trioxy) and PEO150 ($\overline M _{\rm n}$ = 150 Da) in the case of PEEAs. The copolymers showed a decrease of Tm and crystallinity values as compared with PCL. Within each class of copolymers, the bulk hydrophilicity increased with increasing the number of oxyethylene groups in the chain repeat unit. PEEAs were more hydrophilic than PEEs with a similar number of oxyethylene groups. Discrete spherical particles were prepared by both PEEs and PEEAs and their BSA encapsulation efficiency related to copolymer properties. Interestingly, the insertion of short hydrophilic segments is enough to significantly affect protein distribution inside microspheres and its release profiles, as compared to PCL microspheres. Different degradation rates and mechanisms were observed for copolymer microspheres, mainly depending on the distribution of oxyethylene units along the chain. The results highlight that a fine control over the structural parameters of amphiphilic PCL‐based multi‐block copolymers is a key factor for their application in the field of protein delivery.

Release profiles of BSA from microspheres in 0.01 M phosphate buffer and CLSM images of BSA‐loaded microspheres.

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Release profiles of BSA from microspheres in 0.01 M phosphate buffer and CLSM images of BSA‐loaded microspheres.
Thermodynamic Differences Between Deuterated and Protonated Polystyrenes Evaluated Using Reversed Phase Liquid Chromatography
Authors: Kayillo Sindy , Shalliker R. Andrew , Dennis Gary R.
Published: October 2005

Summary: Deuterated compounds are generally considered to possess very similar properties to their protonated analogues. Reversed phase liquid chromatography (RPLC) was used to measure thermodynamic interactions between deuterated and protonated n‐butyl polystyrenes and a C18 stationary phase. Significant differences in enthalpies and entropies of interaction were observed for deuterated and protonated n‐butyl polystyrenes. This is very important because many techniques, such as small‐angle neutron scattering and neutron reflectivity, assume that the interaction of these molecules are identical.

Structure of n‐butyl polystyrenes.

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Structure of n‐butyl polystyrenes.
Novel Titanium Catalysts Bearing an [O, N, S] Tridentate Ligand for Ethylene Homo‐ and Copolymerization
Authors: Wang Cong , Sun Xiu‐Li , Guo Yang‐Hui , Gao Yuan , Liu Bo , Ma Zhi , Xia Wei , Shi Li‐Ping , Tang Yong
Published: October 2005

Summary: By a sidearm approach, a series of titanium complexes bearing an [O, N, S] tridentate ligand have been synthesized and proven to be highly active for ethylene polymerization. The complexes also show excellent ability to copolymerize ethylene with hex‐1‐ene and norbornene. The effects of the different sidearms on the catalytic behavior of the complexes were studied in detail.

The copolymerization of ethylene with hex‐1‐ene using titanium complexes bearing [O, N, S] tridentate ligands as catalysts.

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The copolymerization of ethylene with hex‐1‐ene using titanium complexes bearing [O, N, S] tridentate ligands as catalysts.
Gelation Studies, 4
Authors: Richter Sven , Matzker Rolf , Schröter Klaus
Published: October 2005

Summary:In a recent paper [S. Richter et al.,Macromol. Rapid Commun.2004,25, 1504] the sol‐gel transition of two thermoreversible gelling mixtures made of xanthan gum and locust bean gum has been studied by using time‐resolved dynamic light scattering (DLS) and low‐amplitude oscillatory shear rheology, and is indicated by the presence of the typical power‐law behaviors in the time‐intensity correlation functiong2(t) − 1 ∝ t−µand in the oscillatory shear experimentG′(ω) ∝ G″(ω) ∝ ωn. A significant and reproducible difference of 7 K for the estimated gelation temperatures was found again, with the higher one always determined by rheology. We now present a logical explanation together with new results obtained on this system that may also be of importance for other ones. The incipient infinite percolated cluster that is formed during the gelation process is more pronounced, and is detectable earlier by rheology than by DLS for this present system.

Double‐logarithmic plot of the time‐intensity correlation functionsg2(t) − 1 versus the delay timetand at a scattering angle ofθ = 90° and at several temperatures of the mixture.

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Double‐logarithmic plot of the time‐intensity correlation functionsg2(t) − 1 versus the delay timetand at a scattering angle ofθ = 90° and at several temperatures of the mixture.
Effect of Organic Modification on the Compatibilization Efficiency of Clay in an Immiscible Polymer Blend
Authors: Sinha Ray Suprakas , Bousmina Mosto
Published: October 2005

Summary: This communication describes the effect of organic modifier miscibility with the matrices, and the effect of the initial interlayer spacing of the organoclay, on the overall morphology and properties of an immiscible polycarbonate/poly(methyl methacrylate) blend. By varying the organic‐modifier‐specific interactions with the blend matrices at the same time as changing the initial interlayer spacing of the organoclay, different levels of compatibilization were revealed. The evidence for the interfacial compatibilization of the organoclay was assessed by scanning electron microscopy observations and was supported by differential scanning calorimetry analyses. The effect on the level of clay exfoliation was also examined.

Differential scanning calorimetry scans of virgin, montmorillonite, and various organically modified montmorillonite‐compatibilized 40PC/60PMMA blends

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Differential scanning calorimetry scans of virgin, montmorillonite, and various organically modified montmorillonite‐compatibilized 40PC/60PMMA blends
Hydrogen exchange mass spectrometry for the analysis of protein dynamics
Authors: Wales Thomas E. , Engen John R.
Published: October 2005

Hydrogen exchange coupled to mass spectrometry (MS) has become a valuable analytical tool for the study of protein dynamics. By combining information about protein dynamics with more classical functional data, a more thorough understanding of protein function can be obtained. In many cases, protein dynamics are directly related to specific protein functions such as conformational changes during enzyme activation or protein movements during binding. The method is made possible because labile backbone hydrogens in a protein will exchange with deuterium atoms when the protein is placed in a D2O solution. The subsequent increase in protein mass over time is measured with high‐resolution MS. The location of the deuterium incorporation is determined by monitoring deuterium incorporation in peptic fragments that are produced after the labeling reaction. In this review, we will summarize the general principles of the method, discuss the latest variations on the experimental protocol that probe different types of protein movements, and review other recent work and improvements in the field. © 2005 Wiley Periodicals, Inc.
Synthesis of isoelectronic polyazomethine and poly(arylene vinylene) by a palladium‐catalyzed Suzuki coupling method
Authors: Grigoras Mircea , Antonoaia Nicoleta Cristina
Published: October 2005

Two fully conjugated copolymers containing 2,7‐(9,9‐dioctyl) fluorene and 3,6‐(N‐hexyl‐9H‐carbazole) disubstituted rings and arylene vinylene or azomethine units in the main chain were synthesized through a palladium‐catalyzed Suzuki coupling method of 2,7‐bis(4,4,5,5‐tetramethyl‐1,3,2‐dioxaborolan‐2‐yl)‐9,9‐dioctyl fluorene with 1,4‐bis(6‐bromo‐N‐hexyl‐9H‐carbazole‐3‐yl vinyl) benzene or N,N‐bis(6‐bromo‐N‐hexyl‐9H‐carbazole‐3‐yl methylidene) 1,4‐phenylenediamine. Bisbromine arylene vinylene and arylenazomethine monomers were synthesized by condensation of 3‐formyl‐N‐hexyl‐6‐bromo carbazole with tetraethyl‐p‐xylylene diphosphonate or 1,4‐phenylenediamine. Copolymers were characterized by FTIR, 1H‐NMR, DSC, UV‐visible and photoluminescence methods. Copyright © 2005 Society of Chemical Industry
In situ compatibilization of polystyrene/polyolefin elastomer blends by the Friedel–Crafts alkylation reaction
Authors: Guo Zhenghong , Tong Lifang , Fang Zhengping
Published: October 2005

Blends of polystyrene (PS) with polyolefin elastomer (POE) were prepared by a reactive extrusion method. In order to increase the compatibility of the two blending components, a Lewis acid catalyst, aluminium chloride (AlCl3), was adopted to initiate the Friedel–Crafts alkylation reaction. Fourier‐transform infrared (FTIR) spectra of the PS/POE/AlCl3 blends extracted with butanone verified the graft structure between the PS and POE. Because the in situ generated PS‐graft‐POE copolymers acted as compatibilizers, the mechanical properties of PS/POE blends were greatly improved. For example, after compatibilization, the Charpy impact strength of an 80/20 (wt%) PS/POE blend was increased from 6.29 to 8.50 kJ m−2. Scanning electron microscopy (SEM) showed that the size of the droplets decreased from 9–10 µm to less than 2 µm with the addition of AlCl3. Gel permeation chromatography (GPC) showed competition between the grafting reaction and the degradation of blending components in the presence of AlCl3. Copyright © 2005 Society of Chemical Industry
Macromolecular design via reversible addition–fragmentation chain transfer (RAFT)/xanthates (MADIX) polymerization
Authors: Perrier Sébastien , Takolpuckdee Pittaya
Published: October 2005

Among the living radical polymerization techniques, reversible addition–fragmentation chain transfer (RAFT) and macromolecular design via the interchange of xanthates (MADIX) polymerizations appear to be the most versatile processes in terms of the reaction conditions, the variety of monomers for which polymerization can be controlled, tolerance to functionalities, and the range of polymeric architectures that can be produced. This review highlights the progress made in RAFT/MADIX polymerization since the first report in 1998. It addresses, in turn, the mechanism and kinetics of the process, examines the various components of the system, including the synthesis paths of the thiocarbonyl‐thio compounds used as chain‐transfer agents, and the conditions of polymerization, and gives an account of the wide range of monomers that have been successfully polymerized to date, as well as the various polymeric architectures that have been produced. In the last section, this review describes the future challenges that the process will face and shows its opening to a wider scientific community as a synthetic tool for the production of functional macromolecules and materials. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43:5347–5393, 2005
Imidazole‐initiated polymerizations of α‐amino acid N‐carboxyanhydrides – simultaneous chain‐growth and step‐growth polymerization
Authors: Kricheldorf Hans R. , Von Lossow Colin , Schwarz Gert
Published: October 2005

The N‐carboxyanhydrides (NCAs) of sarcosine (Sar), D,L‐leucine (D,L‐Leu), D,L‐phenylalanine (D,L‐Phe), and L‐alanine (L‐Ala) were polymerized in dioxane. Imidazole served as initiator and the NCA/initiator ratio was varied from 1/1 to 40/1. The isolated polypeptides were characterized by 1H NMR spectroscopy, by MALDI‐TOF mass spectrometry, by viscosity measurements, and by SEC measurements in the case of poly(sarcosine). Cyclic oligopeptides were found in all reaction products and in the case of polySar, poly(D,L‐Leu), and poly(D,L‐Phe) the cycles were the main products. In the case of poly(L‐Ala), rapid precipitation of β‐sheet lamellaes prevented efficient cyclizations and stabilized imidazolide endgroups. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 5690–5698, 2005
Self‐assembly of a new class of amphiphilic poly(amidoamine) dendrimers and their electrochemical properties
Authors: Wang Bing‐Bing , Zhang Xin , Jia Xin‐Ru , Li Zi‐Chen , Ji Yan , Wei Yen
Published: October 2005

Amphiphilic poly(amidoamine) (PAMAM) dendrimers consisting of a hydrophilic dendrimer core and hydrophobic aromatic dansyl or 1‐(naphthalenyl)‐2‐phenyldiazene (NPD) shells have been synthesized. These amphiphilic dendrimers from the zero generation to the third generation self‐assemble into vesicular aggregates in water. The self‐assembly behavior of these dendrimers strongly depends on their generations. The generation dependence has been further investigated by an exploration of their electrochemical properties. For the PAMAM–NPD aggregates, the photoisomerization process leads to a change in the aggregate size. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 5512–5519, 2005
CH and CN Radical Contribution in the Particle Formation Generated in a Radio‐Frequency CH4/N2 Plasma
Authors: Pereira Jérémy , Massereau‐Guilbaud Véronique , Géraud‐Grenier Isabelle , Plain André
Published: October 2005

Summary: The generation of particles in a CH4/N2 radio‐frequency discharge has been studied in order to understand the effect of nitrogen incorporation into the particles. The nitrogen increase in the gas mixture leads to a modification of the particle behaviour in the plasma bulk. Moreover, for nitrogen ratios higher than 50%, changes in particle morphology and texture are observed. These modifications may be explained by the appearance of new radicals like CN evidenced, thanks to optical emission spectroscopy (OES). Moreover, the evolution of CH and CN emission lines has been studied. On the other hand, IR analyses have shown the presence of CN, NH, CH bonds in the particles and in the coatings. Their proportions depend on the nitrogen flow rate. A correlation between OES results and IR analyses has been established.

Particles obtained in a 10% CH4/90% N2 mixture.

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Particles obtained in a 10% CH4/90% N2 mixture.
7th International Symposium on Ionizing Radiation and Polymers – IRaP2006
Authors: Güven Olgun
Published: October 2005

Plasma News: This section contains news of the plasma community all over the world. Articles about, for example, people, projects, and market trends are welcome. Suggestions should be sent to the editorial office of the Plasma Processes and Polymers, preferably by E‐mail to plasma@wiley‐vch.de. The editorial office decides which articles will be published.
Impulse Oscillometry vs. Body Plethysmography in Assessing Respiratory Resistance in Children
Authors: Tomalak Waldemar , Radliński Jakub , Pawlik Jacek , Latawier Wojciech , Pogorzelski Andrzej
Published: October 2005

In 334 children aged 5–18 years, we compared the results of plethysmographic measurements of airway resistance (Raw) with oscillometric (impulse oscillometry; IOS) assessment of respiratory properties of the respiratory system (resistance (R) at 5, 20, and 35 Hz). All three resistances correlated significantly with plethysmographic Raw, and the strongest correlation was seen for R5 (r = 0.64). R5, R20, and R35 were significantly greater than Raw in the whole group. In the group of children with obstruction (FEV1%FVC below lower limit of normal), R5 was still greater than Raw, while R20 and R35 were not. The Bland‐Altman analysis comparing plethysmographic measurements with oscillometric R5 revealed a significant difference between Raw and R5 in the whole group, which disappeared in the group of obstructed patients. Oscillometric assessment of resistive properties of the respiratory system of the lung requires less patient cooperation than does plethysmography. As the results of measurements using oscillometric R5 are similar to those obtained by plethysmography, IOS may be useful in diagnosing children with obstructive respiratory diseases. Pediatr Pulmonol. © 2005 Wiley‐Liss, Inc.
Refinement of unbound protein docking studies using biological knowledge
Authors: Heuser Philipp , Baù Davide , Benkert Pascal , Schomburg Dietmar
Published: October 2005

In this work we present two methods for the reranking of protein–protein docking studies. One scoring method searches the InterDom database for domains that are available in the proteins to be docked and evaluates the interaction of these domains in other complexes of known structure. The second one analyzes the interface of each proposed conformation with regard to the conservation of Phe, Met, and Trp and their polar neighbor residues. The special relevance of these residues is based on a publication by Ma et al. (Proc Natl Acad Sci USA 2003;100:5772–5777), who compared the conservation of all residues in the interface region to the conservation on the rest of the protein's surface. The scoring functions were tested on 30 unbound docking test cases. The evaluation of the methods is based on the ability to rerank the output of a Fast Fourier Transformation (FFT) docking. Both were able to improve the ranking of the docking output. The best improvement was achieved for enzyme–inhibitor examples. Especially the domain‐based scoring function was successful and able to place a near‐native solution on one of the first six ranks for 13 of 17 (76%) enzyme–inhibitor complexes [in 53% (nine complexes) even on the first rank]. The method evaluating residue conservation allowed us to increase the number of good solutions within the first 100 ranks out of ∼9000 in 82% of the 17 enzyme–inhibitor test cases, and for seven (41%) out of 17 enzyme–inhibitor complexes, a near native solution was placed within the first seven ranks. Proteins 2005. © 2005 Wiley‐Liss, Inc.
Gesprengte Ketten – Absicherung der Supply Chain durch ein unternehmensweites Business Continuity Management
Authors: Engel Helge
Published: October 2005

In den vergangenen Jahren sind in vielen Unternehmen einseitig ausgerichtete Optimierungs‐Programme (Cost‐Cutting) durchgeführt worden. Diese haben die Abhängigkeiten von Zulieferern, Gebäuden, Anlagen und Maschinen sowie Serviceeinrichtungen spürbar erhöht. Dementsprechend führen unvorhergesehene Störungen der Versorgungskette (etwa durch Qualitätsmängel bei einem bedeutenden Zulieferer oder den Ausfall von Warehousing‐Funktionen nach einem Rechner‐Defekt) heute auch zu deutlich höheren Schadenpotenzialen. Die Gründe dafür liegen auf der Hand: Single‐Sourcing‐Ansätze, die Konzentration von bestimmten und wesentlichen Funktionen auf nur einen – oder einige wenige – Standorte/Anlagen und die generell steigende Abhängigkeit der Produktions‐ und Logistikprozesse von der Verfügbarkeit der IT‐Systeme könnten im Falle des Falles das Unternehmen schlagartig treffen und den Wertschöpfungsprozess abrupt unterbrechen. Als Folge des Rückganges von Betriebsleistungen (beispielsweise aufgrund schlagartig gesunkener Kapazitäten, fehlender Rohstoffe und Halbfertigwaren oder der Nicht‐Verfügbarkeit von Daten und Anwendungen) wird die Gewinn‐ und Verlustrechnung des Unternehmens durch Ertragsausfälle und/oder zusätzlich entstehende Kosten zur Schadenminderung und zur Stabilisierung des Marktes direkt belastet.
Bruchlandung – Krisen‐Widerstandsfähigkeit der Swissair
Authors: Rues Raphael
Published: October 2005

Für den Zusammenbruch des Swissair‐Konzerns wird in sehr personalisierter Weise das Versagen der Unternehmensführung verantwortlich gemacht. Der Öffentlichkeit und insbesondere den ehemaligen Mitarbeitern der Swissair erscheint der Kollaps als eine Art “Act of God” mit einem Vorlauf von nur wenigen Jahren oder sogar Monaten. Das Eintreten eines plötzlichen, unvorhergesehenen Ereignisses wie die Vernichtung von 10–15 Milliarden Schweizer Franken wird bestenfalls einer kleinen Gruppe zugeschrieben. Doch Frühwarnindikatoren hatte es mindestens seit 1993 gegeben.
Alles im Fluss: Geschäftsprozessbasierte Notfallplanung
Authors: Wagschal Herbert , Huth Michael
Published: October 2005

Die betriebliche Notfallplanung konzentriert sich häufig auf die im Geschäftsbetrieb eingesetzten Ressourcen. So soll durch Nutzung technischer Lösungen auf mögliche Notfälle reagiert werden können. Derartige Lösungen können zu einer ineffizienten Ressourcenverteilung führen, da die potenziellen Schäden eines Notfalls nicht oder nur zweitrangig berücksichtigt werden. Der im Folgenden vorgestellte Ansatz zur Notfallplanung fokussiert dagegen die Geschäftsprozesse eines Unternehmens. Er berücksichtigt die möglichen Schäden bei einer Störung der Prozesse durch einen Notfall und ermöglicht hiermit die Ableitung kosteneffizienter Notfallmaßnahmen.
On the dynamic version of the minimum hand jerk criterion
Authors: Svinin Mikhail , Masui Yohei , Luo Zhi‐Wei , Hosoe Shigeyuki
Published: October 2005

This paper is concerned with the problem of trajectory formation of humanlike reaching movements. First, we review conventional criteria of optimality adopted in robotics and computational neuroscience for the prediction of reaching movements and formulate a dynamic version of the minimum hand jerk criteria. We call it a minimum driving force change criterion and check its performance for the free‐space movements. Next, we test the performance of the new criterion for the movements where the human hand is geometrically constrained by the external environment, and for the movements with flexible objects. The main feature of these movements is that the hand velocity profiles are not always bell shaped. Our simulations and initial experimental results show that the minimum driving force change criterion can roughly capture this feature and, therefore, can be a reasonable candidate for modeling of humanlike reaching movements. © 2005 Wiley Periodicals, Inc.
100 Jahre HV‐Pumpe von Wolfgang Gaede. 100th Anniversary of Gaede's High Vacuum Pump
Authors: Henning Hinrich
Published: October 2005

Wolfgang Gaede erfand 1905 eine robuste, schnell wirkende Hochvakuumpumpe, die einfach in der Handhabe war. Sie wurde von E. LEYBOLD’s Nachf. in Lizenz gebaut und eröffnete der Industrie die zuverlässige Anwendung des Hochvakuums für die Produktion. Gaedes Tätigkeit als wissenschaftlicher Berater für E. Leybold endete erst 1945 mit seinem Tod.
Inline‐Beschichtung von optischen Substraten. Inline coating of optical substrates
Authors: Runkel Steffen , Hohn Oliver , Degenhardt Jens , Roos Björn
Published: October 2005

Optische Technologien spielen eine entscheidende Rolle in unserem täglichen Leben. Von der Verbesserung des Sehens, der digitalen Fotographie, bis hin zur Datenkommunikation findet man eine Vielzahl von Anwendungen. Die Beeinflussung des Lichtes erfolgt im wesentlichen durch Linsen. Neben mineralischen Linsen gewinnen hierbei transparente Kunststofflinsen immer mehr an Bedeutung.

Die optischen und mechanischen Eigenschaften der Linsen werden durch hochwertige Beschichtungen entscheidend verbessert. Hierzu zählen in erster Linie Entspiegelungsschichten um die Lichttransmission zu steigern, Hartschichten um die kratzempfindlichen Kunststoffsubstrate zu schützen und Pflegeleichtschichten um die Schmutzanfälligkeit zu reduzieren und das Reinigen der Substrate zu erleichtern.

Im Folgenden werden moderne Vakuumbeschichtungsmethoden zur industriellen Veredelung von optischen Substraten vorgestellt. Im Fokus steht die Beschichtung von transparenten Kunststoffsubstraten wie beispielsweise Brillengläser mittels einer revolutionären Inline‐Technologie. Hierbei werden einerseits alle erforderlichen Beschichtungsschritte in einer vollautomatisierten Anlage integriert und andererseits die in der Ophthalmik übliche Rezeptfertigung durch eine flexible Zusammenstellung des Schichtsystems ermöglicht.
Ionenquellen in der Vakuum‐Dünnschichttechnik. Ion Sources for Vacuum Thin Film Technology
Authors: Reuschling Ralf , Schultheiss Eberhard
Published: October 2005

Ionenquellen kommen in der Vakuum‐Dünnschichttechnik in vielfältigen Bauarten und Anwendungen zum Einsatz. Der Artikel bietet eine Übersicht über die Grundlagen für den Betrieb einer Ionenquelle sowie über den aktuellen Stand der Technik. Er beschreibt dabei die wesentlichen Parameter einer Quelle, typische Bauformen und Applikationen sowie die Komponenten der Stromversorgung.
Multifunktionale Duplex‐PACVD‐Schichtsysteme im Aluminiumdruckguss. Multifunctional duplex PACVD layer systems for aluminium die casting
Authors: Gebauer‐Teichmann Andreas , Klimek Klaus , Rie Kyong‐Tschong
Published: October 2005

Duplex‐PACVD‐Hartstoffschichten sind bereits bewährt zur Standzeiterhöhung von Zerspanungs‐, Umformwerkzeugen im Hinblick auf Adhäsion, Verschleiß, Ermüdung und Korrosion. Die Entwicklung der Herstellung von duplex nanostrukturierten, gradierten und multilayer Schichtsystemen basierend auf Boriden wird beschrieben. Das Ziel dieser Untersuchung besteht in der Optimierung der Oberflächeneigenschaften mittels Ausnutzung und Kombination von Plasmaoberflächenprozessen: Duplex‐Prozess, Gradientenschichten, Multilayer‐Schichtsysteme. Insbesondere Duplex‐Hartstoffschichtsysteme werden hier im PACVD‐Verfahren abgeschieden, im Hinblick auf ihre tribologischen Eigenschaften untersucht und im Aluminiumdruckguss eingesetzt. Praktische Tests wurden ausgeführt. Die in der Volkswagen Gießerei Kassel eingesetzten Schichten präsentierten eine deutliche Standzeiterhöhung und geringere Metallanklebungstendenz. Die Wirtschaftlichkeit beschichteter Druckgusspinolen und ‐kerne ist bewiesen.
Epidemiology of heart failure in a community‐based study of subjects aged ≥57 years: Incidence and long‐term survival
Authors: van Jaarsveld Cornelia H.M. , Ranchor Adelita V. , Kempen Gertrudis I.J.M. , Coyne James C. , van Veldhuisen Dirk J. , Sanderman Robbert
Published: October 2005

Background:

Survival data from hospital‐based or clinical trial studies of patients with chronic heart failure (CHF) do not represent survival in community‐based settings.

Aims:

To determine the incidence of CHF and the associated long‐term survival in a community‐based sample aged ≥57 years and to assess the mortality risk associated with sex and age.

Methods:

This study was part of the Groningen Longitudinal Aging Study.

Results:

Annual incidence of CHF per 1000 ranged from 2.5 in middle aged adults (57–60 years) up to 22.4 in older females (≥80 years) and 28.2 in older males (≥80 years). The 1, 2, 5 and 7‐year survival rates were 74%, 65%, 45%, 32% for patients with CHF, compared to 97%, 94%, 80% and 70% in a matched reference group without CHF. Higher age (≥76 years) was a risk factor for mortality (OR=2.1) and male sex was a risk factor in those aged ≤75 years (OR=1.9) but not for older patients.

Conclusion:

Long‐term survival rates for patients with CHF in the community were worse than the known survival rates from clinical trials. There is a need for studies describing the care of patients with CHF in the community, including the type of care, the provider, the quality of care and the outcome.
Activation of C‐Jun N‐terminal kinase is required for glutathione transferase A4 induction during oxidative stress, not during cell proliferation, in mouse hepatocytes
Authors: Desmots Fabienne , Loyer Pascal , Rissel Maryvonne , Guillouzo André , Morel Fabrice
Published: October 2005

Expression of the mouse glutathione transferase Alpha 4 (mGSTA4) has been studied during hepatocyte isolation and in cultured hepatocytes. Transient mGSTA4 induction during liver disruption correlated to strong oxidative stress and induction of the Jun N‐terminal kinase (JNK) pathway. Similarly, tumor necrosis factor α induced both JNK phosphorylation and mGSTA4 expression while specific JNK inhibitor JNKI1 prevented these two events and JNK activator anisomycin strongly induced mGSTA4 expression. We also found that endogenous JNK and mGSTA4 co‐immunoprecipitate. A second mGSTA4 induction occurred 2 days after cell seeding concomitantly to DNA replication and was prevented by treatment with mitogen‐activated protein kinase (MEK) inhibitor U0126. Our data demonstrate that mGSTA4 is strongly increased during oxidative stress possibly via JNK pathway and during proliferation via MEK/extracellular signal‐regulated kinase pathway, and suggest that mGSTA4 might be an endogenous regulator of JNK activity by direct binding.
The intracellular domain of Notch ligand Delta1 induces cell growth arrest
Authors: Kolev Vihren , Kacer Doreen , Trifonova Radiana , Small Deena , Duarte Maria , Soldi Raffaella , Graziani Irene , Sideleva Olga , Larman Barry , Maciag Thomas , Prudovsky Igor
Published: October 2005

Notch signaling involves proteolytic cleavage of the transmembrane Notch receptor after binding to its transmembrane ligands, Delta or Jagged; and the resultant soluble intracellular domain of Notch stimulates a cascade of transcriptional events. The Delta1 ligand also undergoes proteolytic cleavage upon Notch binding, resulting in the production of a free intracellular domain. We demonstrate that the expression of the intracellular domain of Delta1 results in a non‐proliferating senescent‐like cell phenotype which is dependent on the expression of the cell cycle inhibitor, p21, and is abolished by co‐expression of constitutively active Notch1. These data suggest a new intracellular role for Delta1.
Biphasic changes in the levels of poly(ADP‐ribose) polymerase‐1 and caspase 3 in the immature brain following hypoxia–ischemia
Authors: Martin Shannon S. , Perez‐Polo J. Regino , Noppens Kristin M. , Grafe Marjorie R.
Published: October 2005

Poly(ADP‐ribose) polymerase‐1 (PARP‐1) is a DNA repair‐associated enzyme that has multiple roles in cell death. This study examined the involvement of PARP‐1 in ischemic brain injury in the 7‐day old rat, 0.5–48 h after unilateral carotid artery ligation and 2 h of 7.8% oxygen. This experimental paradigm produced a mild to moderate injury; 40–67% of animals in the ligated groups had histological evidence of neuronal death. Ipsilateral cortical injury was seen at all survival times, while mild contralateral cortical injury was seen only at the 1 h survival time. Hippocampal injury was delayed relative to the cortex and did not show a biphasic pattern. Immunohistochemical staining for PARP showed bilateral increased staining as early as 1 h post‐hypoxia. PARP staining at early time periods was most intense in layer V of cortex, but did not demonstrate a pattern of cell clusters or columns. Ipsilateral PARP‐1 levels quantified by western blotting showed a biphasic pattern of elevation with peaks at 0.5 and 12 h post‐hypoxia. Contralateral PARP‐1 levels were also elevated at 0.5 and 24 h. PARP activity as determined by immunoreactivity for poly(ADP‐ribose) (PAR) was increased ipsilaterally at 0.5, 2 and 12 h survival times. Cortical caspase 3‐activity was increased ipsilaterally at 6, 12, and 24 h and contralaterally at 0.5, 1, 2 and 6 h post‐hypoxia.

There are three main findings in this study. First, changes in the distribution and amount of cell death correlate well with measured PARP‐1 levels after hypoxia–ischemia, and both display biphasic characteristics. Second, there are significant early, transient morphological and biochemical changes in the contralateral cortex after neonatal hypoxia–ischemia due to unilateral permanent occlusion of a carotid artery followed by 2 h of systemic hypoxia. Third, variability in the responses of individual pups to hypoxia–ischemia suggests the presence of unidentified confounding factors.
Organic-walled microfossils and biostratigraphy of the upper Port Nolloth Group (Namibia): implications for latest Neoproterozoic glaciations
Authors: GAUCHER CLAUDIO , FRIMMEL HARTWIG E. , GERMS GERARD J. B.
Published: October 2005

The occurrence of organic-walled microfossils is reported for the first time from the Neoproterozoic Port Nolloth Group, Gariep Belt (southern Namibia). Acritarchs assigned to Bavlinella faveolata occur in the Hilda Subgroup below the younger of two glaciogenic diamictite units (Numees Formation) within the Port Nolloth Group. The microfossil assemblage in the overlying upper Holgat Formation, above the Numees Formation, is characterized by low diversity (six species), dominance of Soldadophycus bossii, and absence of acanthomorphic or large sphaeromorphic acritarchs. The agglutinated foraminifer Titanotheca also occurs in the Holgat Formation. Combined with available chemostratigraphic data and Pb–Pb ages, this microfossil assemblage indicates an upper Ediacaran age of around 555 Ma for the Holgat Formation. Virtually identical microfossil assemblages, negative-to-positive δ13 C trends,87Sr/86Sr values between 0.7080 and 0.7085, as well as Pb–Pb carbonate ages, make it possible to correlate the Holgat Formation with the Buschmannsklippe Formation (Witvlei Group, central Namibia), the Kombuis Member (Cango Caves Group, southern South Africa) and the uppermost Polanco to lowermost Cerro Espuelitas Formation (Arroyo del Soldado Group, Uruguay). Based on these data, the underlying Numees Formation, the age of which has been only loosely constrained so far and subject to considerable debate, can now be assigned to the c. 580 Ma Gaskiers or the possibly younger (< 570 Ma) Moelv glacial event. The Numees glacial event may be represented in the uppermost Nooitgedagt Member (Cango Caves Group, South Africa) and the lower Barriga Negra formations (Arroyo del Soldado Group, Uruguay), characterized by a negative δ13C excursion and a strong sea-level drop. If this correlation is confirmed, lack of glacial deposits there might have implications for the palaeogeographic extent of upper Ediacaran glaciations. Our preliminary studies show that acritarch biostratigraphy can make a significant contribution to unravelling the stratigraphy of Neoproterozoic glacial deposits, especially when combined with C and Sr isotopic data.
Medical co-morbidity and validity of DSM-IV depression criteria
Authors: SIMON GREGORY E. , VON KORFF MICHAEL
Published: October 2005

Background. Clinicians have questioned the validity of depression criteria in patients with chronic medical illness, but few empirical data address this question.

Method. Computerized records identified two samples of managed care patients beginning depression treatment: 235 with diabetes, ischemic heart disease, or chronic obstructive lung disease and 204 without those conditions. Telephone assessments at baseline, 2 months, and 6 months included the Structured Clinical Interview for DSM-IV and other measures of depression severity and functional status. Item Response Theory analyses compared patterns of depressive symptoms across groups and specifically evaluated somatic symptoms (fatigue, change in weight or appetite, psychomotor agitation/retardation, and sleep disturbance) as indicators of depression. Logistic regression examined how change in somatic symptoms during treatment varied between patient groups.

Results. Overall item response analysis indicated differential item functioning between groups (χ2=33·7, df=18, p=0·017). Two of eight item-level comparisons were statistically significant; one in the predicted direction (patients with co-morbidity reported more fatigue at low levels of depression: χ2=17·9, df=1, p<0·001) and one in the opposite direction from predicted (patients with co-morbidity reported less psychomotor agitation/retardation at low levels of depression: χ2=8·0, df=1, p=0·005). Observed differences were modest: at the midpoint of the depression severity scale, patients with medical co-morbidity had a 54% probability of reporting fatigue compared to 45% in those without co-morbidity. All four somatic symptoms showed robust improvement with treatment, and this improvement did not differ significantly between patients with and without medical co-morbidity.

Conclusions. We find only limited evidence that fatigue, changes in weight or appetite, psychomotor agitation/retardation, and sleep disturbance are less valid indicators of depression in patients with chronic medical illness. DSM-IV criteria for diagnosis of depression do not require significant modification for patients with medical co-morbidity.
Frequency and clinical, neuropsychological and neuroimaging correlates of apathy following stroke – the Sydney Stroke Study
Authors: BRODATY HENRY , SACHDEV PERMINDER S. , WITHALL ADRIENNE , ALTENDORF ANNETTE , VALENZUELA MICHAEL J. , LORENTZ LISA
Published: October 2005

Background. The frequency and clinical, neuropsychological and neuroimaging correlates of apathy in patients who have had a stroke are inadequately defined.

Method. A total of 167 consecutive patients admitted to the stroke units of two university hospitals after an ischaemic stroke and 109 controls received extensive medical, psychiatric and neuropsychological assessments; a subset received a magnetic resonance imaging (MRI) scan. The groups were matched for sex and age. Patients were assessed 3–6 months after their stroke. The sample for this study comprised 135 patients and 92 controls who completed the Apathy Evaluation Scale (AES).

Results. Apathy was present in 26·7% of stroke patients compared to 5·4% of controls. Apathetic stroke patients were older, more functionally dependent and had lower Mini-Mental State Examination (MMSE) scores than those without apathy. Apathy was not associated with risk factors for cerebrovascular disease or stroke severity. There was a weak but significant correlation between apathy and self-reported depression but not with clinician-rated depression. Neuropsychologically, after correction for age, premorbid intelligence (IQ) and depression, apathy was associated with reduced attention and speed of information processing. On neuroimaging there were trends for associations of apathy with the extent of hyperintensities in the right hemisphere and right fronto-subcortical circuit, but not with total stroke volume or number of strokes.

Conclusions. Apathy is common following a cerebrovascular event. Presence of apathy may be related to older age and right fronto-subcortical pathway pathology, rather than stroke severity. It is associated with functional impairment and cognitive deficits.