bluuebunny/crossref_metadata_2025 huggingface dataset:
Synthesis and Binding Properties of Dendritic Oxybathophenanthroline Ligands towards Copper(II)
Authors: Stephan Holger , Geipel Gerhard , Bernhard Gert , Comba Peter , Rajaraman Gopalan , Hahn Uwe , Vögtle Fritz
Published: October 2005

Dendritic oxybathophenanthroline ligands (generation 0 to 3) have been synthesized by treatment of 4,7‐bis(4′‐hydroxyphenyl)‐1,10‐phenanthroline with the corresponding Fréchet‐type dendrons carrying a benzylic bromide function at the focal point. The complexation of copper(II) has been studied by liquid–liquid extraction using the radioisotope 64Cu and time‐resolved laser‐induced fluorescence spectroscopy (TRLFS) in organic media indicating the formation of 1:3 complexes (Cu:dendritic ligand). Electronic and EPR spectroscopy were used to characterize the copper(II) chromophore, which is shown to have the expected distorted square‐planar geometry with two phenanthroline donors coordinated to the copper(II) center. The third dendritic ligand therefore is proposed to be bound by secondary interactions. The stability constants of the 1:3 complexes were found to be in the order of log K ≈ 16 in CHCl3. On the other hand, increasing generation of the dendritic Fréchet‐type branches leads to enhanced shielding of the copper ion from the environment. Additional information about this behaviour was obtained by the fluorescence lifetimes, which are much less influenced upon addition of copper(II) salt to solutions of the higher generation ligands. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
A Novel Five‐Coordinate Rhodium(I) Complex
Authors: Koshevoy Igor O. , Sizova Olga V. , Tunik Sergey P. , Lough Alan , Poë Anthony J.
Published: October 2005

An unusual five‐coordinate isomer of the mononuclear complex [Rh(CO)2(PPh3)2I] has been isolated, and its crystallographic structure determined. The molecule has a slightly distorted trigonal‐bipyramidal structure, with both PPh3 ligands being in axial positions. A combination of IR and NMR spectroscopy with the results of DFT calculations shows that the complex maintains the same structure in solution. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Novel sulfonated hydrogel composite with the ability to inhibit proteases and bacterial growth
Authors: Vachon David J. , Yager Dorne R.
Published: October 2005

There is a growing interest in the development of wound dressings that possess functionality beyond providing physical protection and an optimal moisture environment for the wound. To this end, a novel dressing material based on a sulfonated triblock polymer has been developed. This versatile polymer possesses an ion‐exchange capability that is amenable to binding and controlled release of a variety of therapeutic agents. This sulfonated polymer offers several advantages over existing commercial hydrogels used as wound dressings. These include (1) hydrophilicity that is proportional to sulfonation level, (2) easy preparation of fabric supported dressings (e.g., polyester, cotton, nylon), (3) excellent mechanical integrity of the materials when hydrated, (4) stability to a variety of chemistries, and (5) stability to a variety of sterilization methodologies. In this study, polymer was coated onto a polyester fabric and then modified by ion exchange to prepare the sodium, silver, or doxycycline salts. These sulfonated triblock polymer formulations were then evaluated for their capacity to sequester the neutrophil proteases, elastase, and collagenase‐2 (MMP‐8). Several of the formulations were found to sequester significant amounts of either elastase or collagenase. These formulations were demonstrated to be tested against a commercially available dressing that is currently marketed for its protease‐inhibiting capability. The experimental dressing was statistically superior to the commercial dressing at inhibiting MMP‐8 and elastase under the same conditions. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res, 2006
An analysis of the integration between articular cartilage and nondegradable hydrogel using magnetic resonance imaging
Authors: Ramaswamy Sharan , Wang Dong‐An , Fishbein Kenneth W. , Elisseeff Jennifer H. , Spencer Richard G.
Published: October 2005

A hydrogel is a highly hydrated polymer gel suitable for use as a scaffold for tissue engineering. One important application is to the repair of cartilage defects due to injury or osteoarthritis. Integration of the hydrogel with surrounding tissue is critical for the long‐term functionality of the implant; however direct visualization of integration is difficult and invasive. Accordingly, we used MRI to noninvasively investigate the integration of hydrogel in cartilage. Two integration methods were assessed: (1) cartilage‐initiated and (2) chemical, using chondroitin sulphate–methacrylate‐aldehyde (CS‐MA‐ald) as an adhesive. These were compared to a control group, that is, standard, nonintegrated hydrogel photopolymerization. Spatial variation of the transverse relaxation time, T2, across the transition region was used to determine the effectiveness of integration. In the CS‐MA‐ald group only, two interfaces were found. This provides evidence of an intermediate adhesive layer between hydrogel and cartilage. Second, the thickness of the transition region between hydrogel to cartilage in the CS‐MA‐ald group was 1.32 mm as compared to 1.20 mm and 1.17 mm in the tissue‐initiated and nonintegrated groups, respectively. We interpret this as a more gradual transition region of hydrogel to cartilage and hence a greater degree of integration when an adhesive layer is present. © 2005 Wiley Periodicals, Inc. Published 2005 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2006
HPTLC‐densitometric method of determination of oleanolic acid in the Lamii albi flos
Authors: Wójciak‐Kosior Magdalena , Krzaczek Tadeusz , Matysik Grazyna , Skalska Agnieszka
Published: October 2005

HPTLC combined with densitometric method was used to determine the content of oleanolic acid in acetone extract from the Lamii albi flos L. The plant extract was separated on Si 60 HPTLC plates and determined with the use of two densitometric methods: measurement of fluorescence and absorbance. The content of oleanolic acid was statistically calculated. In a measurement of absorbance in 1 g of the dry Lamii albi flos L. 1458 μg of oleanolic acid was determined (0.147%). In a fluorescence method in 1 g of the plant material 1516 μg of oleanolic acid was determined (0.149%).
Sodium glycylglycine as effective electrolyte run buffer for ascorbic and uric acid separation by CZE: A comparison with two other CE assays
Authors: Zinellu Angelo , Sotgia Salvatore , Caddeo Salvatore , Deiana Luca , Carru Ciriaco
Published: October 2005

A new CE method for ascorbic acid (AA) and uric acid (UA) detection in human plasma has been developed. Analytes were resolved in less than 4 min by employing sodium glycylglycine (Glygly) as electrolyte run buffer at pH 8.0. Using the diode array detector ability to measure multiple wavelengths simultaneously, detection was optimized by monitoring the run at 262 nm for AA and at 288 nm for UA. Electrophoretic parameters such as resolution, migration times, efficiency, and peak areas of this new method were compared to those obtained by the two CE assays described in literature, in which the analytes separation was achieved by using sodium borate (that allows faster migration times but poor resolution) or tricine (with the highest resolution but elevated migration times) as electrolyte run buffer. Sodium Glygly allows to obtain the same good resolution given by the tricine buffer but with the faster analysis times of the sodium borate run buffer. Ascorbate and urate levels were measured in 35 healthy volunteers by the three methods and the obtained data were compared by three different statistical tests (mountain plot, Passing–Bablok regression, and Bland–Altman test) in order to verify the accuracy of our proposed method.
Separation and characterization of antioxidants from Spirulina platensis microalga combining pressurized liquid extraction, TLC, and HPLC‐DAD
Authors: Jaime Laura , Mendiola José A. , Herrero Miguel , Soler‐Rivas Cristina , Santoyo Susana , Señorans F. Javier , Cifuentes Alejandro , Ibáñez Elena
Published: October 2005

A new procedure has been developed to separate and characterize antioxidant compounds from Spirulina platensis microalga based on the combination of pressurized liquid extraction (PLE) and different chromatographic procedures, such as TLC, at preparative scale, and HPLC with a diode array detector (DAD). Different solvents were tested for PLE extraction of antioxidants from S. platensis microalga. An optimized PLE process using ethanol (generally recognized as safe, GRAS) as extraction solvent has been obtained that provides natural extracts with high yields and good antioxidant properties. TLC analysis of this ethanolic extract obtained at 115°C for 15 min was carried out and the silica layer was stained with a DPPH∗︁ (diphenyl‐pycril‐hydrazyl) radical solution to determine the antioxidant activity of different chromatographic bands. Next, these colored bands were collected for their subsequent analysis by HPLC‐DAD, revealing that the compounds with the most important antioxidant activity present in Spirulina extracts were carotenoids, as well as phenolic compounds and degradation products of chlorophylls.
Preparation and Characterization of Microwave‐treated Carboxymethyl Chitin and Carboxymethyl Chitosan Films for Potential Use in Wound Care Application
Authors: Wongpanit Panya , Sanchavanakit Neeracha , Pavasant Prasit , Supaphol Pitt , Tokura Seiichi , Rujiravanit Ratana
Published: October 2005

Summary: CM‐chitin and CM‐chitosan films were successfully crosslinked by microwave treatment. Crosslinking of the microwave‐treated CM‐chitin films involved mainly the carboxylate and the secondary alcohol groups, while crosslinking of microwave‐treated CM‐chitosan films involved the carboxylate and the amino groups. In addition, the crystallinity of CM‐chitin increased with increasing microwave treatment time, whereas an increase in the crystallinity of the microwave‐treated CM‐chitosan films was not observed. At a similar percentage of weight loss, the crosslinking of either CM‐chitin or CM‐chitosan films by microwave treatment required much less stringent condition when compared with the crosslinking by autoclave treatment. Based on both direct and indirect cytotoxicity assays, the cytotoxicity of the microwave‐treated CM‐chitin films was negative, while that of the microwave‐treated CM‐chitosan films was positive. Human fibroblasts adhered on the surface of microwave‐treated CM‐chitosan films much better than on the surface of microwave‐treated CM‐chitin films.

Total amount of protein synthesis of living NHGF cells that were cultured on chitin, microwave‐treated CM‐chitin, chitosan, microwave‐treated CM‐chitosan films.

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Total amount of protein synthesis of living NHGF cells that were cultured on chitin, microwave‐treated CM‐chitin, chitosan, microwave‐treated CM‐chitosan films.
pH/Temperature – Sensitive Imprinted Ionic Poly(N‐tert‐butylacrylamide‐co‐acrylamide/maleic acid) Hydrogels for Bovine Serum Albumin
Authors: Demirel Gökhan , Özçetin Gökçen , Turan Eylem , Çaykara Tuncer
Published: October 2005

Summary: In this study, we have prepared pH/temperature‐sensitive imprinted ionic poly(N‐tert‐butylacrylamide‐co‐acrylamide/maleic acid) [P(TBA‐co‐AAm/MA)] hydrogels for bovine serum albumin (BSA) by using molecular imprinting method. BSA adsorption from aqueous BSA solutions was investigated with two types of hydrogel systems prepared by non‐imprinted and imprinted methods. Hydrogels imprinted with BSA showed higher adsorption capacity and specificity for BSA than hydrogels prepared by the usual procedure. At all studied conditions, the highest BSA adsorption was observed in the hydrogel imprinted with 8.63 wt.‐% BSA. In addition, the imprinted hydrogels exhibited both for good selectivity BSA and high adsorption rate depending on the number of BSA‐sized cavities. Adsorption studies showed that other stimuli, such as pH, temperature and initial BSA concentration also influenced the BSA adsorption capacity of both non‐imprinted and imprinted hydrogels.

Effect of pH on BSA adsorption.

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Effect of pH on BSA adsorption.
Organization of Polyhydroxyalkanoate Synthase for In Vitro Polymerization as Revealed by Atomic Force Microscopy
Authors: Kikkawa Yoshihiro , Narike Masaharu , Hiraishi Tomohiro , Kanesato Masatoshi , Sudesh Kumar , Doi Yoshiharu , Tsuge Takeharu
Published: October 2005

Summary: Individual polyhydroxyalkanoate synthase molecules from Ralstonia eutropha (PhaCRe) were directly visualized on highly oriented pyrolytic graphite (HOPG) by atomic force microscopy (AFM). PhaCRe molecule was observed as a spherical particle of 2.9 ± 0.4 nm in height and 28 ± 4 nm in width. In vitro polymerization reaction on HOPG was carried out for 5 min by reacting the PhaCRe molecules with (R)‐3‐hydroxybutyryl‐CoA monomers. The reaction product was then observed after the removal of water solution. Several PhaCRe molecules associated with each other to form an assembly, which was attached to a fibrillar structure of ca. 0.2–0.3 nm in height. The fibrillar structure that elongated from the PhaCRe assembly was interpreted as the poly[(R)‐3‐hydroxybutyrate] polymer chain. High resolution AFM suggested that the PhaCRe assembly was composed of 3–4 subunits of PhaCRe molecules. This was further supported by SDS‐PAGE analysis of the cross‐linked PhaCRe enzyme. These results suggest that more than two subunits of PhaCRe are necessary for the in vitro polymerization of PHB molecular chains.

AFM image of PhaCRe molecules after in vitro polymerization reaction for 5 min.

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AFM image of PhaCRe molecules after in vitro polymerization reaction for 5 min.
Adhesion Contact Dynamics of Fibroblasts on Biomacromolecular Surfaces
Authors: Fang Ning , Zhu Aiping , Chan‐Park Mary B. , Chan Vincent
Published: October 2005

Summary: Biomacromolecules like gelatin and chitosan have emerged as highly versatile biomimetic coatings for applications in tissue engineering. The elucidation of the interfacial kinetics of cell adhesion on biomacromolecular surfaces will pave the way for the rational design of chitosan/gelatin‐based systems for cell regeneration. Biomacromolecular ultra‐thin films, chemically immobilized on fused silica are ideal experimental models for determining the effect of surface properties on the biophysical cascades following cell seeding. In this study, confocal reflectance interference contrast microscopy (C‐RICM), in conjunction with phase contrast microscopy and fluorescence confocal microscopy, was applied to detect the adhesion contact dynamics of 3T3 fibroblasts on chitosan and gelatin ultrathin films. X‐ray photoelectron spectroscopy (XPS) confirmed the immobilization of chitosan or gelatin on the silanized glass surface. Both the initial cell deformation rate and the change of two‐dimensional spread area of the 3T3 fibroblasts are higher on gelatin‐modified surfaces than on chitosan surfaces. The steady‐state adhesion energy of 3T3 fibroblasts on gelatin film is three times higher than that on chitosan film. Immuno‐staining of actin further demonstrates the different organization of cytoskeleton, likely induced by the change in cell signaling mechanism on the two biomacromolecular surfaces. The better attachment of 3T3 fibroblast to gelatin is postulated to be caused by the presence of adhesive domains on gelatin.

C‐RICM images of a typical 3T3 cell on a gelatin‐immobilized substrate.

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C‐RICM images of a typical 3T3 cell on a gelatin‐immobilized substrate.
Cover Picture: Macromol. Chem. Phys. 19/2005
Authors: Naga Naofumi
Published: October 2005

Cover: Copolymerizations of ethylene and disubstituted diallylsilanes (A2R2Si) (CH2CHCH2)2R2Si (R = CH3, C6H5) have been investigated with zirconocene catalysts. The stereospecific catalysts showed higher reactivity for A2R2Si monomers than the aspecific ones. A2R2Si monomers were incorporated in the polymer chain via cyclization insertion, and formed 3,5‐disubstituted silacyclohexane unit. Further details can be found in the Full Paper by N. Naga on page 1959.
A Novel Route to Multiphase Polymer Systems Containing Nano‐Droplets: Radical Polymerization of Vinylic Monomers in Gelled Water‐in‐Oil Miniemulsions
Authors: Holtze Christian , Landfester Katharina , Antonietti Markus
Published: October 2005

Summary: A new strategy for the synthesis of composite polymers with larger volume fraction of aqueous inclusions less than 1 µm in diameter is presented. A water‐in‐oil miniemulsion of aqueous droplets in a continuous, cross‐linkable monomer phase is prepared. The addition of an organo‐gelator allows the immobilization of the droplets in a solid gel, thus avoiding the usual demixing upon polymerization of the continuous phase. This pregelled system is then converted into a composite polymer by photoinitiated free radical polymerization. Such coatings may be used for an improved climate control of buildings or as a deposit for the controlled release of actives from polar nano‐droplets.

SEM image of a cross‐linked composite polymer showing controlled droplet inclusions with a maximal diameter of 500 nm.

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SEM image of a cross‐linked composite polymer showing controlled droplet inclusions with a maximal diameter of 500 nm.
Functionalized Star‐Like Polystyrenes as Organic Supports of a Tridentate Bis(imino)pyridinyliron/Aluminic Derivative Catalytic System for Ethylene Polymerization
Authors: Bouilhac Cécile , Cloutet Eric , Cramail Henri , Deffieux Alain , Taton Daniel
Published: October 2005

Summary: Star‐like polystyrenes composed of a microgel core with arms functionalized with a few hydroxy‐ or methoxy‐ended ethylene oxide units were used as organic supports for a tridentate bis(imino)pyridinyliron catalyst towards ethylene polymerization. When used as supports of 2,6‐bis[1‐2,6(diisopropylphenyl)imino]ethylpyridynyl iron dichloride in the presence of various alkylaluminium compounds, the supported catalysts enabled the production, with a high catalytic activity, of polyethylene beads of a spherical morphology and high bulk density. A good control of the polyethylene molar mass distribution could also be achieved, which was explained by a lowering of the transfer reaction to the aluminium derivative, as compared to homogeneous conditions.

SEM image of PE particles prepared in the presence of trimethylaluminium supported on a PS microgel with an iron catalyst (TMA/Fe = 800).

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SEM image of PE particles prepared in the presence of trimethylaluminium supported on a PS microgel with an iron catalyst (TMA/Fe = 800).
Liquid Crystalline Dendritic Networks Derived from Poly(propylene imine) (PPI) Dendrimers
Authors: Marcos Mercedes , Martín‐Rapún Rafael , Serrano José‐Luis , Sánchez‐Ferrer Antoni
Published: October 2005

Summary: A nematic liquid crystalline network based on a poly(propylene imine) dendrimer [PPI‐(NH2)32 (G = 4)] was prepared in the form of films. In the network the PPI dendritic molecules are partially functionalised with a chiral aldehyde and are connected to each other by an achiral dialdehyde. The phase behaviour of the network was investigated by polarising‐light optical microscopy, differential scanning calorimetry, and X‐ray diffractometry. Thermoelastic measurements ruled out the possible elastomeric nature of the material.

Schematic of the nematic dendritic network prepared here.

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Schematic of the nematic dendritic network prepared here.
A urodynamics protocol to optimally assess men with post‐prostatectomy incontinence
Authors: Huckabay Chad , Twiss Christian , Berger Aaron , Nitti Victor W.
Published: October 2005

Aims

To propose a urodynamic protocol to comprehensively assess all parameters of post prostatectomy incontinence (PPI).

Methods

Sixty men with a history of PPI after radical prostatectomy prospectively underwent a standardized video urodynamics protocol. A 7F urethral catheter was used for standard cystometry, abdominal leak point pressure (ALPP), and pressure flow measurements. The International Continence Society nomogram classified obstruction and further classification of obstruction was based on fluoro voiding cystourethrography and non‐invasive flow rates (free Qmax).

Results

Twenty‐four (40%) men had detrusor overactivity with 8 (13%) also having detrusor overactivity incontinence. Only one patient had impaired compliance. All men had urodynamic stress incontinence, but 21 (35%) men demonstrated it only after removal of the urethral catheter. For men leaking with and without the urethral catheter, the respective ALPP was significantly different, 86.3 and 67 cmH2O, respectively (P = 0.002). The men who leaked only in the absence of the urethral catheter had significantly higher ALPP measurements, P < 0.001. After reclassification using the fluoroscopic images of the bladder outlet and free Qmax, only 13.3% patients were obstructed.

Conclusions

The proposed urodynamic protocol allows for an optimal assessment of bladder and sphincter dysfunction and outlet obstruction in men with PPI. © 2005 Wiley‐Liss, Inc.
Are patient symptoms predictive of the diagnostic and/or therapeutic value of hydrodistention?
Authors: Cole Emily E. , Scarpero Harriette M. , Dmochowski Roger R.
Published: October 2005

Introduction

Hydrodistention (HD) has been utilized as a diagnostic and therapeutic tool in patients with refractory and diverse pelvic floor symptoms, including bladder pain with or without irritative bladder symptoms such as urinary urgency and urinary frequency. We sought to determine whether we could better define in whom HD was a more valuable intervention by stratifying patients according to presenting symptoms.

Materials and Methods

A retrospective review was performed on 185 patients who underwent HD at our institution by a single surgeon between 1/2002–8/2004. Subjects were placed into groups according to their symptoms. Group 1 (G1) patients reported pain with bladder filling that was relieved with emptying, group 2 (G2) reported constant pelvic pain unrelated to bladder filling or emptying, and group 3 (G3) reported urgency and frequency alone with no pain component. Anesthetic capacity, presence and severity of glomerulations post‐distention, and follow‐up at 1, 3, and 6 months were recorded for each patient.

Results

G1 included 40 patients with mean age of 42 (R = 16–77), G2 included 101 patients with mean age of 46 (R = 20–76), and G3 22 patients with mean age of 40 (R = 20–84). The mean anesthetic capacity was 715 ml, 725 ml, and 542 ml for G1, G2, and G3 respectively. ANOVA revealed a statistically significant reduction in the capacity of G3 when compared with the others (P = 0.0072). Glomerulations were present in 74% of G1, 72% of G2, and 86% of G3 patients. 61%, 33%, & 0% of G1 patients reported improvement at 1, 3, and 6 months respectively, 54%, 25%, & 7% of G2 patients reported improvement, and 50%, 19%, & 7% of G3 patients reported improvement. There were no statistically significant differences in the responses amongst the three groups.

Conclusions

Although HD is frequently employed for patients with refractory pelvic pain and/or lower urinary tract complaints, results failed to identify any statistically significant differences in post‐distention objective findings (anesthetic capacity, glomerulations) or therapeutic benefits when patients are categorized according to presenting symptoms. Neurourol. Urdynam. © 2005 Wiley‐Liss, Inc.
HPLC‐MS/MS analysis of willow bark extracts contained in pharmaceutical preparations
Authors: Kammerer Bernd , Kahlich Rainer , Biegert Claudia , Gleiter Christoph H. , Heide Lutz
Published: October 2005

Preparations containing willow bark extract are popular herbal remedies, but they are mostly standardised with respect to only one compound (usually salicin). RP‐HPLC using a C18‐column eluted with water:methanol: tetrahydrofuran and coupled to electrospray triple‐quadrupole MS and MS/MS was used for the characterisation of dried extracts of Salix spp. and for the identification of their constituents. Comparison with reference substances led to the identification of 13 compounds (saligenin, salicylic acid, salicin, isosalicin, picein, salidroside, triandrin, salicoylsalicin, salicortin, isosalipurposide, salipurposide, naringenin‐7‐O‐glucoside and tremulacin). Two pharmaceutical preparations containing willow bark extract, used in clinical trials and labelled Salix daphnoides and S. purpurea × daphnoides extracts, were compared using the described method and exhibited several clear differences, the most prominent of which was the possible presence of picein in the former preparation. The described method may be utilised for the characterisation of herbal medicines in order to ensure comparability of medication in further clinical trials. Copyright © 2005 John Wiley & Sons, Ltd.
Fracture toughness of modified polypropylene/poly(styrene‐ran‐butadiene) blends
Authors: Hristov Velichko , Lach Ralf , Krumova Marina , Grellmann Wolfgang
Published: October 2005

Fracture toughness of polypropylene (PP)/poly(styrene‐ran‐butadiene) rubber (SBR) blends as a function of concentration of maleic anhydride (MA) in the maleated polypropylene (MAPP) compatibilizer was investigated under uniaxial static and impact loading conditions. The addition of MAPP to the unmodified PP/rubber blend enhanced the tensile modulus and yield stress as well as the Charpy impact strength. The maximum values were recorded at 1.0 wt% grafted MA in the compatibilizer. V‐shaped blunt‐notched specimens exhibited typical ductile behavior and no breakage of the specimens occurred during the impact fracture tests. Sharp‐notched specimens of uncompatibilized and low‐content MA blends broke in a semibrittle manner, supported by a rapid crack propagation process. Increasing MA content in the blends led to semibrittle‐to‐ductile transition characterized by stable crack propagation. Fracture mechanics experiments, supplemented by scanning electron microscopy (SEM), were also employed to obtain a better understanding of the fracture and deformation behavior. Copyright © 2005 Society of Chemical Industry
Modeling the molecular weight distribution of block copolymer formation in a reversible addition–fragmentation chain transfer mediated living radical polymerization
Authors: Monteiro Michael J.
Published: October 2005

Block copolymers have become an integral part of the preparation of complex architectures through self‐assembly. The use of reversible addition–fragmentation chain transfer (RAFT) allows blocks ranging from functional to nonfunctional polymers to be made with predictable molecular weight distributions. This article models block formation by varying many of the kinetic parameters. The simulations provide insight into the overall polydispersities (PDIs) that will be obtained when the chain‐transfer constants in the main equilibrium steps are varied from 100 to 0.5. When the first dormant block [polymer–SC(Z)S] has a PDI of 1 and the second propagating radical has a low reactivity to the RAFT moiety, the overall PDI will be greater than 1 and dependent on the weight fraction of each block. When the first block has a PDI of 2 and the second propagating radical has a low reactivity to the RAFT moiety, the PDI will decrease to around 1.5 because of random coupling of two broad distributions. It is also shown how we can in principle use only one RAFT agent to obtain block copolymers with any desired molecular weight distribution. We can accomplish this by maintaining the monomer concentration at a constant level in the reactor over the course of the reaction. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 5643–5651, 2005
Plasma Co‐Polymerisation of Two Strongly Interacting Monomers: Acrylic Acid and Allylamine
Authors: Beck Alison J. , Whittle Jason D. , Bullett Nial A. , Eves Paula , Mac Neil Sheila , McArthur Sally L. , Shard Alexander G.
Published: October 2005

Summary: Plasma co‐polymerisation presents an exciting opportunity to produce coatings with mixtures of functional species that are difficult to achieve from single monomer systems. Unfortunately, the complexity of reactions in the plasma environment can make it difficult to predict and characterise the coating chemistries. In this study, X‐ray photoelectron (XP) and near edge X‐ray absorption fine structure (NEXAFS) spectroscopy have been used to examine coatings prepared by the co‐polymerisation of allylamine and acrylic acid. As expected, a mixture of chemical groups including amines, nitriles, amides and acids were identified. Significantly, the copolymers showed strong evidence of protonated amine (based on the N 1s XP spectra) and carboxylate anions (based on the NEXAFS O K edge); species that were not evident in coatings produced from the individual parent monomers. The results suggest that as the two monomers mix in the gas phase, allylammonium acrylate salts form and may act as a third monomer during the plasma polymerisation. The results also indicated that the addition of acrylic acid monomer suppressed the dehydrogenation of amines to nitriles and increasing the proportion of nitrogen as amine species at the interface. We speculate that these coatings will exhibit zwitterionic characteristics in aqueous solution and that they may find utility in the isoelectric focussing and separation of proteins from solution.

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Auf der sicheren Seite – Informationssicherheitsmanagement und IT‐Governance
Authors: Böhmer Wolfgang
Published: October 2005

Treten im Zusammenhang mit einem kritischen Geschäftsprozess infrastrukturelle IT‐Störungen auf, so sind oftmals längere Ausfallzeiten mit erheblichen Kosten die Folge. Leider werden solche Störungen und Risiken bei der Prävention immer noch kaum oder wenig ins Kalkül gezogen [KES/KPMG 2002]. Eines der wichtigen Probleme im Sicherheitsmanagement besteht darin, dass mit der Entwicklung hin zu verteilten IT‐Systemen die Einschätzung der Sicherheitslage immer schwieriger wird. Zugleich ist das Bewusstsein für IT‐Risiken allgemein unzureichend – erst langsam macht sich bei den Unternehmen die Erkenntnis breit, dass allein die Absicherung der IT‐Komponenten nicht mehr ausreicht. Auch ist die IT‐Sicherheitsorganisation weiterhin das Stiefkind der Unternehmen [KES/KPMG 2002]. Vor diesem Hintergrund gewinnt der Begriff IT‐Governance zunehmend an Bedeutung. Dabei kann IT‐Governance zurückgeführt werden auf die Führung, Organisationsstrukturen und Prozesse, die sicherstellen, dass die IT die Unternehmensstrategie und deren Ziele unterstützt. Um die heute zur Verfügung stehenden Verfahren und Modelle zur IT‐ oder Informationssicherheit hinsichtlich ihrer Unterstützung der IT‐Governance zu überprüfen, werden nachfolgend das IT‐Grundschutzmodell des Bundesamts für Sicherheit in der Informationstechnologie (BSI) dem British Standard 7799 gegenübergestellt.
It's a journey, not a project
Authors: Mestchian Payman
Published: October 2005

Die Bedeutung des Risikomanagements für die Sicherung und Steigerung des Unternehmenswertes wird von immer mehr Unternehmen erkannt. Die hiermit verbundenen Erfolgspotenziale lassen sich am Besten mit Hilfe eines unternehmensweiten Risikomanagements (Enterprise Risk Management, ERM) ausschöpfen, das die pro‐aktive und ganzheitliche Steuerung sämtlicher Unternehmensrisiken erlaubt. Wir sprachen mit Payman Mestchain über die Herausforderungen bei der Implementierung eines solchen Ansatzes.
Sensory‐motor control mechanism for reaching movements of a redundant musculo‐skeletal arm
Authors: Tahara Kenji , Luo Zhi‐Wei , Arimoto Suguru , Kino Hitoshi
Published: October 2005

This paper studies the human arm's sensory‐motor control mechanism in reaching movements. First, we formulate both the kinematics and dynamics of a two‐link planar arm model with six redundant muscles. The nonlinear muscle dynamics is modeled based on several biological understandings. We then show the stability of the overall system and perform some numerical simulations. By considering the internal forces induced by the redundant muscles, we show that the damping factors in each joint can be regulated, and as the result, it can realize humanlike quasistraight line reaching movements. In addition, we also propose the gravity compensation method at the muscle input level and present the result of numerical simulation to verify the usefulness of this method. © 2005 Wiley Periodicals, Inc.
Patterns in groundwater nitrogen concentration in the riparian zone of a large semi‐arid river (River Murray, Australia)
Authors: Lamontagne Sébastien , Leaney Fred W. , Herczeg Andrew L.
Published: October 2005

Lateral exchanges of surface water between river channels and their floodplains are important for vegetation health and aquatic food‐web productivity in semi‐arid ecosystems. However, the significance of the lateral connectivity via sub‐surface pathways in these systems is not as well understood. Patterns in nitrogen concentration in groundwater and in the unsaturated zone were used to infer the sub‐surface biogeochemistry of N in the riparian zone of a large semi‐arid floodplain (Hattah‐Kulkyne National Park) of the River Murray, Australia. The riparian zone plays a special role in this system as it is an area of transition between fresh surface waters and saline floodplain groundwater. The river was losing water to the floodplain during baseflow conditions but gradients were temporarily reversed following floods. In general, the redox conditions were sub‐oxic to anoxic in riparian groundwater and the main forms of N present were NH and dissolved organic N. There was a gradient in NH concentration from the river to the floodplain, suggesting that the main source of NH was from the decomposition of organic matter in fluvial sediments. Elevated concentrations of NO were occasionally found in shallow groundwater away from the river following floods but tended not to persist. The source of the NO appeared to be unsaturated‐zone NO displaced to the water table during floods. Assuming that denitrification was the main attenuation process, this displacement of unsaturated zone NO to anoxic groundwater could be a significant N removal process from the ecosystem (estimated at 18 kg N ha−1 for the largest flood during the study). Understanding the impact of river regulation on floodplain nutrient cycles in River Murray floodplains will be challenging because the changes in floodplain hydrology are complex and coincide with salinization of soils and groundwater. Copyright © 2005 John Wiley & Sons, Ltd.
Energietransport in Flüssigkeitsringmaschinen. Energy Flow in Liquid Ring Machines
Authors: Hebecker Dietrich , Nitzsche Thomas
Published: October 2005

Der Energietransport vom Laufrad der Flüssigkeitsringmaschine zum zu verdichtenden Gas erfolgt mit einem flüssigen Verdränger. Dieser Weg ist aufgrund der turbulenten Strömung und der Gehäusereibung der Flüssigkeit stark verlustbehaftet. Der Fluss der Energie und Entstehung der Verluste werden betrachtet.
Mechatronische Lösungen für trockenlaufende Vakuumpumpen. Mechatronic solutions for dry vacuum pumps
Authors: Kösters Heiner
Published: October 2005

Mit den heutigen Möglichkeiten der Elektronik und Leistungselektronik und einer mechatronischen Vorgehensweise, stehen Möglichkeiten zur Verfügung, die noch vor wenigen Jahren undenkbar waren. Die modernen modularen Systeme im Ex‐Bereich ermöglichen optimierte Lösungen für den Prozess und die bestehende Gesamtanlage aus standardisierten Komponenten zusammenzustellen. Hierdurch können die modernen Möglichkeiten zur Zustandsüberwachung und Systemeinbindung genutzt und gleichzeitig die Kosten zur Systemeinbindung und der Aufwand für die Inbetriebnahme dramatisch reduziert werden.
Gezielte Manipulation von Mikropartikeln in einem Plasma. Manipulation of micro‐disperse particles in a process plasma
Authors: Basner Ralf , Fehske Holger , Kersten Holger. , Kosse Sylvio. , Schubert Gerald
Published: October 2005

Für die Behandlung, d. h. die Oberflächenmodifizierung oder Beschichtung, von mikro‐dispersen Materialien (Pulver, Granulate, Fasern etc.) in einem Prozessplasma ist das Verständnis der Plasma‐Teilchen‐Wechselwirkung von großem Interesse. Zu diesem Zweck werden entsprechende experimentelle Untersuchungen in einer neuartigen Apparatur PULVA‐INP vorgestellt.
A Note on the Estimator of the Alpha Coefficient for Standardized Variables Under Normality
Authors: Hayashi Kentaro , Kamata Akihito
Published: October 2005

The asymptotic standard deviation (SD) of the alpha coefficient with standardized variables is derived under normality.
The research shows that the SD of the standardized alpha coefficient becomes smaller as the number of examinees and/or items increase. Furthermore, this research shows that the degree of the dependence of the SD on the number of items is a function of the average correlation coefficients. When the average correlation approaches 1, the SD of the alpha coefficient decreases rapidly as the number of items increase, with the order of p. On the other hand, when the items are only weakly correlated, increasing the number of items decreases the SD of the alpha coefficient at a much slower rate.
Strategy implementation in obsessive–compulsive disorder and trichotillomania
Authors: CHAMBERLAIN SAMUEL R. , BLACKWELL ANDREW D. , FINEBERG NAOMI A. , ROBBINS TREVOR W. , SAHAKIAN BARBARA J.
Published: October 2005

Background. The use of strategies to aid performance when undertaking neuropsychological tasks is dependent on intact fronto-striatal circuitry, and growing evidence suggests impaired spontaneous use of strategies in patients with obsessive–compulsive disorder (OCD). However, studies to date have not examined the effects of strategy training on task performance in OCD or in trichotillomania (compulsive hair-pulling, a condition that has been argued to share overlap with OCD in terms of phenomenology and co-morbidity).

Method. The ability to generate novel visuospatial sequences using a computer interface was examined before and after undertaking optimal strategy training in 20 OCD patients, 17 trichotillomania patients, and 20 controls (matched for age, education, and IQ).

Results. OCD patients failed to improve ability to generate novel sequences above baseline despite successfully completing strategy training to the same extent as other groups. In contrast, performance of trichotillomania patients improved significantly after training to the same extent as controls. Groups did not differ on memory span, trial-by-trial action monitoring, or ability to generate novel visuospatial sequences prior to strategy training.

Conclusions. Strategy implementation deficits, suggestive of cognitive inflexibility and fronto-striatal dysfunction, appear integral to the neurocognitive profile of OCD but not trichotillomania. Future research should investigate cognitive flexibility in obsessive–compulsive spectrum disorders using a variety of paradigms, and clarify the contribution of specific neural structures and transmitter systems to deficits reported.
Point prevalence of bulimia nervosa in 1982, 1992, and 2002
Authors: KEEL PAMELA K. , HEATHERTON TODD F. , DORER DAVID J. , JOINER THOMAS E. , ZALTA ALYSON K.
Published: October 2005

Background. Recent epidemiological data suggest a decline in bulimia nervosa (BN) incidence in primary care. We sought to examine BN point prevalence from 1982 to 2002 in a college population.

Method. In 1982, 1992, and 2002, 800 women and 400 men were randomly sampled from a university for a study of health and eating patterns. Participation rates were 72% in women and 63% in men, resulting in n=2491 participants.

Results. BN point prevalence decreased significantly in women over the period of observation. Eating Disorder Inventory Bulimia scores decreased across cohorts, and these decreases remained significant when male and female and Caucasian and non-Caucasian students were analyzed separately.

Conclusion. These data support a decline in BN rates that cannot be attributed to changes in service utilization. Changing socio-cultural factors may explain a true decrease in BN incidence and prevalence.
Specifying race-ethnic differences in risk for psychiatric disorder in a USA national sample
Authors: BRESLAU JOSHUA , AGUILAR-GAXIOLA SERGIO , KENDLER KENNETH S. , SU MAXWELL , WILLIAMS DAVID , KESSLER RONALD C.
Published: October 2005

Background. Epidemiological studies have found lower than expected prevalence of psychiatric disorders among disadvantaged race-ethnic minority groups in the USA. Recent research shows that this is due entirely to reduced lifetime risk of disorders, as opposed to persistence. Specification of race-ethnic differences with respect to clinical and social characteristics can help identify the protective factors that lead to lower lifetime risk among disadvantaged minority groups.

Method. Data on 5424 Hispanics, non-Hispanic Blacks, and non-Hispanic Whites came from the National Comorbidity Survey Replication, a nationally representative survey conducted with the World Mental Health version of the Composite International Diagnostic Interview. Race-ethnic differences in risk of disorders were compared across specific diagnoses, ages of onset, cohorts and levels of education.

Results. Both minority groups had lower risk for common internalizing disorders: depression, generalized anxiety disorder, and social phobia. In addition, Hispanics had lower risk for dysthymia, oppositional-defiant disorder and attention deficit hyperactivity disorder; non-Hispanic Blacks had lower risk for panic disorder, substance use disorders and early-onset impulse control disorders. Lower risk among Hispanics, relative to non-Hispanic Whites, was found only among the younger cohort (age [les ]43 years). Lower risk among minorities was more pronounced at lower levels of education.

Conclusion. The pattern of race-ethnic differences in risk for psychiatric disorders suggests the presence of protective factors that originate in childhood and have generalized effects on internalizing disorders. For Hispanics, but not for non-Hispanic Blacks, the influence of these protective factors has emerged only recently.
Effects of aerobic–anaerobic transient conditions on sulfur and metal cycles in sewer biofilms
Authors: Nielsen A. H. , Lens P. , Hvitved-Jacobsen T. , Vollertsen J.
Published: October 2005

Interactions between sulfur and metals were studied in aerobic and anaerobic biofilms grown on domestic waste water at 15°C. The dominant metals in the waste water were iron, zinc and copper, which were present in average concentrations of 0.5mg/l, 0.6mg/l and 0.1m/l, respectively. Copper and zinc were found to accumulate in the anaerobic biofilm owing to precipitation of metal sulfides. Iron supplementation (approximately 5.5mg Fe/l) to the anaerobic waste water reduced the zinc and copper precipitation due to sulfide precipitation with iron. However, even at these elevated iron concentrations in the waste water, sulfide precipitation in the biofilm was controlled largely by zinc and copper. In the aerobic biofilm, addition of iron resulted in accumulation of iron and phosphate, probably owing to precipitation of iron phosphates and iron (oxy)hydroxides. The potential importance of extracellular polymeric substances (EPS) on metal sorption in sewer biofilms was studied. EPS consisted mainly of proteins (13–260mg/(g volatile solids)) and to a lesser extent of carbohydrates (8–26mg/(g volatile solids)). The EPS composition remained relatively constant during experimental runs, but differed significantly between them. No relationships between the metal content of the biofilm and the amount of extracted EPS were found, which suggests that EPS did not play a major role in the metal accumulation.
Mediofrontal Negativities to Averted Gains and Losses in the Slot-Machine Task
Authors: Donkers Franc C.L. , van Boxtel Geert J.M.
Published: October 2005

Abstract: In a previous study we addressed the question whether a feedback-related negativity (FRN) can be elicited by outcomes that are not contingent on any preceding choice or action ( Donkers, Nieuwenhuis, & Van Boxtel, 2005 ). Participants took part in a simple slot-machine task in which they experienced monetary gains and losses in the absence of responses. In addition, they performed a time estimation task often used to study the FRN, and a flanker task known to elicit the error-related negativity (Ne/ERN). Outcomes in the slot-machine task elicited a mediofrontal negativity whose amplitude correlated with the amplitude of the FRN associated with negative feedback in the time estimation task. However, the mediofrontal negativity was observed both for (unfavorable) outcomes that averted a gain and for (favorable) outcomes that averted a loss of money, a finding that is inconsistent with previous FRN research. In the present study we examined the similarity between the mediofrontal negativity observed in the slot-machine task and the frequency-sensitive N2. We manipulated the overall frequency of obtaining gains and losses in the slot-machine task and compared the negativities on averted gains and losses across the different trial probabilities. The results showed that larger feedback-related negativities were elicited by unexpected unfavorable outcomes than by expected unfavorable outcomes.
Error Awareness in a Saccade Countermanding Task
Authors: Endrass Tanja , Franke Cosima , Kathmann Norbert
Published: October 2005

Abstract: Stop-signal tasks can be used to analyze mechanisms of action control and error monitoring. Previous event-related potential (ERP) studies indicated enhanced stop-signal N2 amplitudes for unsuccessful compared with successful inhibition. The aim of this study was to further investigate whether stop-signal related and response-related ERP components would reflect different aspects of error processing. ERPs were recorded during a saccade countermanding task, i.e. a stop-signal task with oculomotor response. Error awareness was obtained from subjective accuracy ratings. The response-related error positivity (Pe) was more pronounced for perceived than for unperceived errors whereas awareness of an error did not modulate the magnitude of the error negativity (Ne). This result is in accordance with previous findings. Stop-signal related ERPs revealed enhanced N2 amplitudes for incorrect (unsuccessfully stopped) trials compared with correct trials. However, this enhancement was restricted to perceived errors. The results support the idea that the stop-signal itself provides a performance feedback and the N2 reflects aspects of conscious response monitoring of unsuccessful inhibition.
External Behavior Monitoring Mirrors Internal Behavior Monitoring
Authors: Bates Alan T. , Patel Tina P. , Liddle Peter F.
Published: October 2005

Abstract: The discovery of mirror neurons in monkeys has reshaped thinking about how the brain processes observed actions. There is growing evidence that these neurons, which show similar firing patterns for action execution and observation, also exist in humans. Many parts of the motor system required to perform a specific action are activated during the observation of the same action. We hypothesized that behavior monitoring that occurs during action execution is mirrored during action observation. To test this, we measured error negativity/error-related negativity (Ne/ERN) while participants performed and observed a Go/NoGo task. The Ne/ERN is an event-related potential that is thought to reflect an error detection process in the brain. In addition to finding an Ne/ERN for performed errors, we found that an Ne/ERN was also generated for observed errors. The Ne/ERN for observed errors may reflect a system that plays a key role in imitation and observational learning.