bluuebunny/crossref_metadata_2025 huggingface dataset:
Chemo‐enzymatic Synthesis and RAFT Polymerization of 6‐O‐Methacryloyl Mannose: A Suitable Glycopolymer for Binding to the Tetrameric Lectin Concanavalin A?
Authors: Granville Anthony M. , Quémener Damien , Davis Thomas P. , Barner‐Kowollik Christopher , Stenzel Martina H.
Published: September 2007

Summary: The chemo‐enzymatic synthesis of 6‐O‐methacryloyl mannose (MaM) glycomonomer was successfully performed for the first time. Subsequent aqueous RAFT polymerization of the monomer yielded well‐defined, linear poly(6‐O‐methacryloyl mannose) (PMaM) glycopolymers without the need for protecting and deprotecting group chemistry. As well as investigating the RAFT polymerization kinetics of this monomer using various initial monomer to chain transfer agent concentration ratios, the protein binding ability of the generated glycopolymer was tested using concanavalin A, a known mannose‐residue binding lectin.
Determinants of firm‐specific thresholds in acquisition decisions
Authors: Folta Timothy B. , O'Brien Jonathan P.
Published: September 2007

We develop a model to explain why some firms make acquisitions, while other firms with equal performance expectations do not. We argue that the decision to acquire is not strictly a function of expected abnormal returns, but also depends on a firm's unique acquisition threshold. Our model posits that the threshold is determined by governance, managerial competence, synergy with assets in place, and synergy with growth options. Our empirical findings, drawn from a sample of over 27 000 US acquisitions, offer strong support for the model, suggesting that firms with low thresholds may choose to invest despite comparatively low abnormal returns. Copyright © 2007 John Wiley & Sons, Ltd.
Microglial activation mediates neurodegeneration related to oligodendroglial α‐synucleinopathy: Implications for multiple system atrophy
Authors: Stefanova Nadia , Reindl Markus , Neumann Manuela , Kahle Philipp J. , Poewe Werner , Wenning Gregor K.
Published: September 2007

The role of microglial activation in multiple system atrophy (MSA) was investigated in a transgenic mouse model featuring oligodendroglial α‐synuclein inclusions and loss of midbrain dopaminergic neurons by means of histopathology and morphometric analysis. Our findings demonstrate early progressive microglial activation in substantia nigra pars compacta (SNc) associated with increased expression of iNOS and correlating with dopaminergic neuronal loss. Suppression of microglial activation by early long‐term minocycline treatment protected dopaminergic SNc neurons. The results suggest that oligodendroglial overexpression of α‐synuclein may induce neuroinflammation related to nitrosive stress which is likely to contribute to neurodegeneration in MSA. Further, we detected increased toll‐like receptor 4 immunoreactivity in both transgenic mice and MSA brains indicating a possible signaling pathway in MSA which needs to be further studied as a candidate target for neuroprotective interventions. © 2007 Movement Disorder Society
Pupil diameter in darkness differentiates progressive supranuclear palsy (PSP) from other extrapyramidal syndromes
Authors: Schmidt Claudia , Herting Birgit , Prieur Silke , Junghanns Susann , Schweitzer Katherine , Globas Christoph , Schöls Ludger , Antoni Sabine , Ferger Dietmar , Reichmann Heinz , Wilhelm Helmut , Berg Daniela , Ziemssen Tjalf
Published: September 2007

The most important features that characterize and differentiate progressive supranuclear palsy from other Parkinsonian syndromes are postural instability, supranuclear gaze palsy, pseudobulbar palsy, parkinsonism, and cognitive disturbances. In this article, we demonstrate that progressive supranuclear palsy patients exhibit pathologically decreased pupil diameters after dark adaptation recorded by TV pupillography. A cut off value of 3.99 mm was defined to differentiate progressive supranuclear palsy patients from patients with other extrapyramidal disorders like Parkinson's disease and multiple system atrophy with a specificity of 86.4% and a sensitivity of 70.8%. Other pupil abnormalities could not be described in patients with extrapyramidal syndromes. © 2007 Movement Disorder Society
Antero‐ventral internal pallidum stimulation improves behavioral disorders in Lesch–Nyhan disease
Authors: Cif Laura , Biolsi Brigitte , Gavarini Sophie , Saux Aude , Robles Santiago Gil , Tancu Cornel , Vasques Xavier , Coubes Philippe
Published: September 2007

The Lesch–Nyhan syndrome is an X‐linked recessive disorder caused by a deficiency in hypoxanthine–guanine phosphoribosyl transferase, a purine salvage enzyme. Affected individuals exhibit a characteristic neurobehavioral disorder with delayed acquisition of motor skills, dystonia, severe self‐mutilations, and aggressive behavior. Deep brain stimulation has been previously proposed for controlling isolated involuntary movements and psychiatric disorders. We applied a double bilateral simultaneous stimulation to limbic and motor internal pallidum in one patient for controlling both behavioral and movement disorders, respectively. The injurious compulsions disappeared; dystonia and dyskinesia were decreased at 28 months follow‐up. © 2007 Movement Disorder Society
Strong solvability of 3‐D Cahn–Hilliard system in elastic solids
Authors: Pawłow Irena , Zaja̧czkowski W. M.
Published: September 2007

In this paper we prove the existence and uniqueness of a strong solution to a 3‐D model of phase separation in elastic solids. The model has the form of an initial‐boundary‐value problem for a nonlinear coupled system of hyperbolic–parabolic type. The key idea of the proof is based on the analysis of the system once‐ and twice differentiated with respect to time variable. The paper develops results of the previous work (Top. Meth. Nonlin. Anal., in press). Copyright © 2007 John Wiley & Sons, Ltd.
A new hybrid velocity integration method applied to elastic wave propagation
Authors: Chen Zhiyun , Steeb Holger , Diebels Stefan
Published: September 2007

We present a novel space–time Galerkin method for solutions of second‐order time‐dependent problems. By introducing the displacement–velocity relationship implicitly, the governing set of equations is reformulated into a first‐order single field problem with the unknowns in the velocity field. The resulting equation is in turn solved by a time‐discontinuous Galerkin approach (Int. J. Numer. Anal. Meth. Geomech. 2006; 30:1113–1134), in which the continuity between time intervals is weakly enforced by a special upwind flux treatment. After solving the equation for the unknown velocities, the displacement field quantities are computed a posteriori in a post‐processing step. Various numerical examples demonstrate the efficiency and reliability of the proposed method. Convergence studies with respect to the h‐ and p‐refinement and different discretization techniques are given. Copyright © 2007 John Wiley & Sons, Ltd.
Longitudinal assessment of immunological status and rate of immune recovery following treatment in children with ALL
Authors: Kosmidis Sofia , Baka Margarita , Bouhoutsou Despina , Doganis Dimitrios , Kallergi Constantina , Douladiris Nikolaos , Pourtsidis Apostolos , Varvoutsi Maria , Saxoni‐Papageorgiou Fotini , Vasilatou‐Kosmidis Helen
Published: September 2007

Background

We prospectively evaluated the immunological status, immune recovery and risk of infection in pediatric ALL patients treated on the BFM 95 protocol.

Procedure

Humoral and cellular immunity were evaluated in 72 children with ALL at the end of intensive therapy and values were compared to those at the completion of therapy and 6‐monthly. Parameters investigated included lymphocyte subpopulation by flow cytometry, immunoglobulin levels by nephelometry, antibody titers to previous immunizations and delayed hypersensitivity with skin testing. Immune responses were correlated to duration of therapy, CNS radiotherapy, age and sex.

Results

Humoral immunity was severely depressed by the end of intensive therapy with low immunoglobulin levels and CD19, improved after therapy cessation. Cellular immune responses were normal at the end of intensive treatment but declined significantly by the end of therapy and both CD4 and CD8 remained low at later evaluation points whereas CD4/CD8 ratio was increasing. Duration of therapy and CNS radiotherapy did not affect the rate of immune recovery whereas female had higher CD19, CD45RO, and IgM and children >7 years had higher CD19 and lower CD16 and CD3DR. Among immunized children, 86.7% maintained protective antibodies to MMR and 63% to polio. Despite impairment of immunity, infections outside the neutropenic periods were common viral illnesses.

Conclusion

Humoral immunity was depressed in children with ALL at the end of intensive therapy but began to recover after cessation of therapy. In contrast, cellular immunity declined significantly by the end of therapy and remained abnormal for at least 1 year post‐therapy. Pediatr Blood Cancer 2008;50:528–532. © 2007 Wiley‐Liss, Inc.
Simultaneous determination of cinnamaldehyde, eugenol and piperine by HPTLC densitometric method
Authors: Gopu C. L. , Aher Suyog , Mehta Hiral , Paradkar A. R. , Mahadik K. R.
Published: September 2007

An HPTLC densitometric method for the simultaneous determination of cinnamaldehyde and eugenol as well as trace amounts of piperine in pepper‐contaminated cinnamon was developed. The applicability of the method was tested with cinnamon bark powder adulterated with pepper powder, cinnamon oil, clove powder, clove oil and a commercial preparation containing cinnamaldehyde and eugenol. The method was validated for specificity, precision, accuracy and robustness. The method was found to be precise for different concentrations of cinnamaldehyde, eugenol and piperine. The accuracy of the method was checked by conducting a recovery study at three different levels. The linearity was found to be in the ranges 52.54–735.56, 533.2–8531.2 and 50–300 ng/spot, respectively, with correlation coefficients of 0.9985 ± 0.04, 0.9982 ± 0.06 and 0.9937 ± 0.11 for cinnamaldehyde, eugenol and piperine. Copyright © 2007 John Wiley & Sons, Ltd.
A reversed‐phase high‐performance liquid chromatographic method for the determination of aloesin, aloeresin a and anthraquinone in Aloe ferox
Authors: Zahn Michael , Trinh Thao , Jeong Mijeong Lee , Wang Desheng , Abeysinghe Padmapriya , Jia Qi , Ma Wenwen
Published: September 2007

A reversed‐phase HPLC method for the quantification of aloesin, aloeresin a and anthraquinone (as barbaloin) in Aloe ferox Miller and aloe‐related products has been developed and validated. The method utilized a C18 column with a water–methanol gradient and UV detection at 297 nm. The method validation included linearity, accuracy, precision, limit of detection, limit of quantitation, specificity and standard solution stability. The method showed good linearity (r > 0.99 for all components) and recovery (>85% for all components). The detection and quantitation limits for barbaloin were determined to be 0.02 and 0.1 ppm at signal‐to‐noise ratios of approximately 3:1 and 10:1, respectively. Copyright © 2007 John Wiley & Sons, Ltd.
Effect of hydroxyl content on the morphology and properties of epoxy/poly(styrene‐co‐allylalcohol) blends
Authors: Prolongo Silvia G. , Salazar Alicia , Ureña Alejandro , Rodríguez Jesús
Published: September 2007

Blends based on epoxy resin and random copolymers, poly(styrene‐co‐allylalcohol) (PS‐co‐PA), were studied. Two PS‐co‐PA copolymers, with different hydroxyl content, and a polyallylalcohol (PA) homopolymer were used to analyze the effect of polyalcohol content. The polymers presented similar values of molar mass. The miscibility of noncured mixtures and the thermal transition behavior of cured blends were investigated by differential scanning calorimetry (DSC) and dynamic mechanical thermal analysis (DMTA). Its morphology was studied using both scanning and transmission electron microscopy (SEM and TEM). While the epoxy/PA blends are homogenous materials, because of the epoxy/hydroxyl reaction, PS‐co‐PA/epoxy blends shows separated phases. In these blends, the presence of a third glass transition, whose value is an intermediate between those of pure components, and the presence of a well‐defined interfacial layer between PS‐co‐PA domains and epoxy matrix indicates a secondary epoxy/hydroxyl reaction. The modification of epoxy resin with PS‐co‐PA provides significant increase in the storage modulus measured by DMTA. POLYM. ENG. SCI., 47:1580–1588, 2007. © 2007 Society of Plastics Engineers
The condensation kinetics of polyphthalamides. I. Diamines and diacids or dimethylesters
Authors: Malluche Jan , Hellmann Goetz P. , Hewel Manfred , Liedloff Hanns‐Jörg
Published: September 2007

Semiaromatic polyamides are high‐performance thermoplastics with a huge potential but also a high price. In this study, the condensation kinetics of aliphatic diamines with aromatic diacids, diesters, and polyesters were investigated, to find ways of producing semiaromatic polyamides at lower costs. The condensation of hexamethylene diamine with phthalic acids and their dimethylesters are discussed in this Part I. The amidation of phthalic acids turned out to proceed like the amidation of adipic acid leading to PA66, only more slowly. The amidation of dimethylphthalates proved to be difficult. It is accompanied by a side reaction of amino alkylation which prevents the growth of long polyamide chains. This side reaction was investigated kinetically in detail, using model compounds that were unable to polymerize. The aim was to provide a basis for attempts to amidate polyesters, in particular, PET, which will be reported in Part II. POLYM. ENG. SCI., 47:1589–1599, 2007. © 2007 Society of Plastics Engineers
Condensation kinetics of polyphthalamides. II. Polyesters and diamines
Authors: Hellmann Edith , Malluche Jan , Hellmann Goetz Peter
Published: September 2007

Polyphthalamides are distinguished by outstanding properties. Only their price keeps them from replacing PA66 in many applications, in particular, in automobiles. This article deals with a simple, economically attractive process of upcycling postconsumer polyethylene terephthalate (PET) waste to polyphthalamides. Basic studies on the amidation of acids and esters were described in Part I. The amidation of esters is accompanied by a side reaction of amine alkylation, which, in the case of polyesters, leads to branching and crosslinking. But the crosslinking can be avoided in mixtures with excessive diamine. Therefore, a heterogeneous amidation process was developed in which solid PET granules are simultaneously dissolved in and amidated by a liquid diamine. As long as the PET‐diamine system is heterogeneous, it reacts under amino excess conditions. Later, when all PET is dissolved, it comes back to stoichiometric conditions again, so long‐chained polyamides can be obtained. In terms of molar mass and viscosity, this amidation of solid PET proceeds very similarly to the amidation of terephthalic acid (TPA), which is so far the common route towards polyphthalamides. PET waste could replace TPA. POLYM. ENG. SCI., 47:1600–1609, 2007. © 2007 Society of Plastics Engineers
The effect of multiwall carbon nanotube on the crystallization, morphology, and rheological properties of nylon1010 nanocomposites
Authors: Wang Biao , Sun Guangping , He Xiaofeng , Liu Jingjiang
Published: September 2007

Nanocomposites based on poly(iminosebacoyl iminodecamethylene) (PA1010) and multiwall carbon nanotubes (MWNTs) were successfully prepared by melt blending technique. environmental scanning electron microscope micrographs of the fracture surfaces showed that not only is there an evenly dispersion of MWNTs throughout the PA1010 matrix but also a strongly interfacial adhesion with the matrix. The combined effect of more defects on MWNTs and low temperature buckling fracture is mainly responsible for the broken tubes. Differential scanning calorimeter results showed that the MWNTs acted as a nucleation agent and increased the crystallization rate and decreased crystallite size. In the linear region, rheological measurements showed a distinct change in the frequency dependence of storage modulus, loss modulus, and complex viscosity particularly at low frequencies. We conclude that the rheological percolation threshold might occur when the content of MWNTs is over 2 wt% in the composites. POLYM. ENG. SCI., 47:1610–1620, 2007. © 2007 Society of Plastics Engineers
Rapid sensing of trace ionic substances with the novel porous monolith type ion exchanger
Authors: Aoki Hidemitsu , Miyano Kazuki , Yano Daisaku , Sano Kazuhiko , Yamanaka Koji , Kimura Chiharu , Sugino Takashi
Published: September 2007

Biological and chemical sensor with a rapid response in microlevel test is required for health and environmental monitor. A novel sensing due to porous ion exchanger with three‐dimensional acceptor has been first attempted to develop a high‐performance sensor. This porous monolith type ion exchanger has an open‐cellular monolith structure with 5–50‐μm diameter pores. The trace amount of inorganic ions dissolved in aqueous solutions can be quantitatively determined with the impedance given by the monolith, which attracts and adsorbs the ions rapidly. We have succeeded in detecting ions with a concentration as low as 10−7 mol. The porous ion exchanger has a potentiality as a high‐performance device for biological and chemical sensing. POLYM. ENG. SCI., 47:1666–1670, 2007. © 2007 Society of Plastics Engineers
Sulphonic acids doped poly(N‐ethyl aniline): A material for humidity sensing application
Authors: Kulkarni Milind V. , Viswanath Annamraju Kasi
Published: September 2007

Substituted polyaniline, poly(N‐ethyl aniline) (PNEA), doped with camphor sulphonic acid (CSA) and p‐toluene sulphonic acid (p‐TSA), was synthesized by single‐step chemical polymerization method using ammonium persulphate as an oxidizing agent. This is a single‐step polymerization process to synthesize directly the conducting emeraldine salt phase of the polymer using CSA and p‐toluene sulphonic acid as dopants. The synthesized polymers were characterized by UV–vis and FTIR spectroscopy, scanning electron microscopy, TGA/SDTA, DSC, and conductivity measurements. This single‐step chemical synthesis method offers a polymer having very good physicochemical properties with good electrical conductivity. High temperature conductivity measurements show “thermal activated behavior.” The change in resistance with respect to % relative humidity (% RH) is observed, when pressed pellets of the polymer were exposed to the broad range of humidity (ranging between 20 and 100% RH). POLYM. ENG. SCI., 47:1621–1629, 2007. © 2007 Society of Plastics Engineers
Dynamic and viscoelastic behavior of natural rubber/layered silicate nanocomposites obtained by melt blending
Authors: Ramorino G. , Bignotti F. , Conzatti L. , Ricco T.
Published: September 2007

Vulcanized natural rubber/layered silicate (montmorillonite) nanocomposites prepared by melt blending with different contents of organoclay (0, 5, 10, 20 wt%) were investigated. The morphological characteristics of the materials were studied by transmission electron microscopy (TEM), wide angle X‐ray diffraction, and dynamic mechanical thermal analysis (DMTA). X‐ray spectra evidence some intercalation of the clay, while TEM results show a good dispersion of the clay and the occurrence of partial delamination. DMTA analysis with varying temperature shows that the peak of the loss modulus broadens by increasing the clay content within the material, though the peak temperature is scarcely affected. Mechanical reinforcement induced by the presence of the clay is evidenced by static tensile tests. At every clay content explored, dynamic experiments show a nonlinear behavior (Payne effect), which strongly increases with the amount of clay incorporated and is considerably more pronounced than in natural rubber filled with comparable amounts of conventional fillers. The viscoelastic behavior of the materials is investigated by recovery tests of low amplitude storage modulus, carried out after the application of a large strain perturbation, and by stress relaxation experiments. POLYM. ENG. SCI., 47:1650–1657, 2007. © 2007 Society of Plastics Engineers
Numerical investigation and visualization of polymer behavior within a capillary die
Authors: Beard M.A. , Tabor G.R. , Ritchie S.J.K. , Evans K.E.
Published: September 2007

Numerical analysis of the flow regime within a capillary rheometer has been studied. The vector‐based Remmelgas‐Harrison‐Leal (RHL), analogous to reptation‐based polymer models, has been used to model the polymer dynamics. A series of computational methods for visualizing the flow characteristics of the whole region of the capillary rheometer are made including the area directly in front of the piston. Model predictions provide qualitative analysis of pressure drops observed at the entrance of the die, necessitating the use of the Bagley ends correction in practical rheology measurements. The results of the numerical code help reveal the complex flow kinematics that are involved in the entrance region to the capillary die as well as the barrel region in front of the rheometer piston. POLYM. ENG. SCI., 47:1688–1694, 2007. © 2007 Society of Plastics Engineers
Toughening of epoxy resin with amine functional aniline acetaldehyde condensate
Authors: Maity T. , Samanta B.C. , Dalai S. , Banthia A.K.
Published: September 2007

The diglycidyl ether of bisphenol‐A (DGEBA) resin was modified with amine functional aniline acetaldehyde condensate (AFAAC) and cured with an ambient temperature curing agent triethylene tetramine. The resulting networks displayed significantly improved fracture toughness. The AFAAC was synthesized by the condensation reaction of aniline and acetaldehyde in the acid medium (pH 4) and characterized by FTIR and NMR spectroscopy, elemental analysis, viscosity measurements, and mole of primary and secondary amine analysis. The DGEBA and AFAAC were molecularly miscible but developed a two‐phase microstructure upon network formation. Epoxy/AFAAC compositions were systematically varied to study the effect of AFAAC concentration on the impact, adhesive, tensile, and flexural properties of modified networks. The dynamic mechanical analysis and scanning electron microscopy studies showed two phase morphology in the cured networks, where AFAAC particles were dispersed. The AFAAC modified epoxy network was thermally stable up to around 280°C. POLYM. ENG. SCI., 47:1695–1702, 2007. © 2007 Society of Plastics Engineers
Elastomer swelling in mixed associative solvents
Authors: Westbrook P.A. , French R.N.
Published: September 2007

The applicability of a linear partition model, which correlates elastomer swell in equilibrium with mixed solvents, is extended to include solutions that exhibit significant self‐association and also cross‐association among the constituents. Combined with Chemical Theory to characterize the behavior of associative solutions, the linear partition model conveniently accounts for both positive and negative excess absorption by elastomers over the entire solution composition. The method requires thermodynamic activity data for each component as a function of concentration, a rational model for the nature of chemical association and one observation of elastomer swell for each chemical species in solution. Prior knowledge of the chemical structure of the elastomer is not required. POLYM. ENG. SCI., 47:1554–1568, 2007. © 2007 Society of Plastics Engineers
Reinforcement of epoxy networks with sulfur‐ and carbon‐based molecular fortifiers
Authors: Lesser Alan J. , Calzia Kevin , Junk Matthais
Published: September 2007

Earlier research with phosphorus‐based molecular fortifiers showed a range of improvements in physical, thermal, and mechanical properties. This contribution introduces sulfur‐ and carbon‐based molecules into a model epoxy network for comparison. Similar improvements inrheological, physical, and select mechanical propertiesare found between the phosphorus and sulfur‐ and carbon‐based fortifiers. Thermal properties are not enhanced with the sulfur and carbon fortifiers. Two of the sulfur compounds phase separate upon cure of the epoxy network and show unique behavior. In addition, infrared spectroscopy is performed to identify possible mechanisms of reinforcement. POLYM. ENG. SCI., 47:1569–1575, 2007. © 2007 Society of Plastics Engineers
Screening flame retardants for plastics using microscale combustion calorimetry
Authors: Lyon Richard E. , Walters R.N. , Stoliarov S.I.
Published: September 2007

Microscale combustion calorimetry (MCC) was evaluated as a screening test for efficacy of flame‐retardant additives in polymers. The MCC method separately reproduces the gas and condensed phase processes of flaming combustion in a nonflaming laboratory test and forces them to completion to obtain intrinsic/material combustion properties. At flame extinction, these MCC combustion properties are comparable in magnitude and effect to the extrinsic factors (sample size and orientation), physical behavior (dripping, swelling), and chemical processes (flame inhibition, charring) associated with flame retardancy. Consequently, MCC properties by themselves cannot correlate flame resistance of plastics over a broad range of flame‐retardant chemical composition. POLYM. ENG. SCI., 47:1501–1510, 2007. © 2007 Society of Plastics Engineers
How is it possible to produce highly oriented yarns of electrospun fibers?
Authors: Moon SungCheal , Farris Richard J.
Published: September 2007

Electrospinning of polymeric nanofibers onto a stationary grounded target produces a nonwoven mat‐like material. Using a rapidly rotating grounded target in the form of a wheel or belt, it is possible to produce significant lengths of highly oriented yarns of electrospun filaments. This observation is difficult to explain when one compares the calculated velocity of an electrospun monofilament with the surface velocity of the grounded target. This study was undertaken to attempt to answer this question. Are the calculated fiber velocities correct? Is the collected electrospun filament really a monofilament? Does the electrospun filament split into multiple filaments or do fibers loop in an oriented manner on the collection wheel? POLYM. ENG. SCI., 47:1530–1535, 2007. © 2007 Society of Plastics Engineers
Preparation of nanoparticles of double‐hydrophilic PEO‐PHEMA block copolymers by AGET ATRP in inverse miniemulsion
Authors: Oh, Jung Kwon , Dong Hongchen , Zhang Rui , Matyjaszewski Krzysztof , Schlaad Helmut
Published: September 2007

Atom transfer radical polymerization with activators generated by electron transfer initiating/catalytic system (AGET ATRP) of 2‐hydroxyethyl methacrylate (HEMA) was carried out in inverse miniemulsion. Water‐soluble ascorbic acid as a reducing agent and mono‐ and difunctional poly(ethylene oxide)‐based bromoisobutyrate (PEO‐Br) as a macroinitiator were used in the presence of CuBr2/tris[(2‐pyridyl)methyl]amine (TPMA) and CuCl2/TPMA complexes. The use of poly(ethylene‐co‐butylene)‐block‐poly(ethylene oxide) as a polymer surfactant resulted in the formation of stable HEMA cyclohexane inverse dispersion and PHEMA colloidal particles. All polymerizations were well‐controlled, allowing for the preparation of well‐defined PEO‐PHEMA and PHEMA‐PEO‐PHEMA block copolymers with relatively high molecular weight (DP > 200) and narrow molecular weight distribution (Mw/Mn < 1.3). These block copolymers self‐assembled to form micellar nanoparticles being 10–20 nm in diameter with uniform size distribution, and aggregation number of ∼10 confirmed by atomic force microscopy and transmission electron microscopy. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 4764–4772, 2007
Random fluorene copolymers with on‐chain quinoxaline acceptor units
Authors: Tsami Argiri , Yang Xiao‐Hui , Galbrecht Frank , Farrell Tony , Li Hongbo , Adamczyk Sylwia , Heiderhoff Ralf , Balk Ludwig Josef , Neher Dieter , Holder Elisabeth
Published: September 2007

Two series of novel random polyfluorene copolymers containing quinoxaline units were prepared by stressing the coupling according to Yamamoto. The first series contains 2,3‐bis‐(4′‐tert‐butyl‐biphenyl‐4‐yl)benzo[g]quinoxaline and the second series 2,3‐bis‐(4′‐tert‐butyl‐biphenyl‐4‐yl)quinoxaline as energy accepting unit. The copolymers were identified by gel permeation chromatography, infrared spectroscopy, and nuclear magnetic resonance spectroscopy. Thermal properties were analyzed by thermal gravimetric analysis and differential scanning calorimetry revealing amorphous copolymers that are stable up to 430 °C. The morphology was investigated using atomic force microscopy. The optical properties in solutions and thin films were analyzed. Furthermore, the thin film electro‐optical properties were determined in monolayer polymer light‐emitting devices. Single layer devices were built with efficiencies ranging from 0.15 to 2.0 cd/A. For the random copolymers with 5 mol % benzo[g]quinoxazoline in the polyfluorene backbone some threefold efficiency enhancement from 1.1 to 3.0 cd/A was achieved by utilizing an ultra thin interlayer of poly(9,9‐di‐n‐octylfluorene‐2,7‐diyl)‐alt‐[1,4‐phenylene‐(4‐sec‐butylphenylimino)‐1,4‐phenylene] between PEDOT:PSS and the emissive random copolymer layer. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 4773–4785, 2007
Docking with PIPER and refinement with SDU in rounds 6–11 of CAPRI
Authors: Shen Yang , Brenke Ryan , Kozakov Dima , Comeau Stephen R. , Beglov Dmitri , Vajda Sandor
Published: September 2007

Our approach to protein–protein docking includes three main steps. First we run PIPER, a new rigid body docking program. PIPER is based on the Fast Fourier Transform (FFT) correlation approach that has been extended to use pairwise interactions potentials, thereby substantially increasing the number of near‐native structures generated. The interaction potential is also new, based on the DARS (Decoys As the Reference State) principle. In the second step, the 1000 best energy conformations are clustered, and the 30 largest clusters are retained for refinement. Third, the conformations are refined by a new medium‐range optimization method SDU (Semi‐Definite programming based Underestimation). SDU has been developed to locate global minima within regions of the conformational space in which the energy function is funnel‐like. The method constructs a convex quadratic underestimator function based on a set of local energy minima, and uses this function to guide future sampling. The combined method performed reliably without the direct use of biological information in most CAPRI problems that did not require homology modeling, providing acceptable predictions for targets 21, and medium quality predictions for targets 25 and 26. Proteins 2007. © 2007 Wiley‐Liss, Inc.
Industrial Statistics: Quality Management, Application and Development
Authors: Tyssedal John
Published: September 2007

The above Special Issue editorial (DOI: 10.1002/qre.880) states the incorrect DOI number for Gerry Hahn's article. The correct number is DOI: 10.1002/qre.863. Also omitted from this editorial is the DOI number of the Barone et al. paper, which is DOI: 10.1002/qre.866. These errors will be corrected prior to print publication.
Guaranteed cost control of T–S fuzzy systems with input delay
Authors: Chen Bing , Lin Chong , Liu Xiaoping , Tong Shaocheng
Published: September 2007

This paper is concerned with the problem of guaranteed cost control for Takagi–Sugeno (T–S) fuzzy systems with time‐varying input delay. The input delay is of interval type, and no restriction is imposed on the derivative of the time delay. Based on free‐weighting matrix method, new delay‐dependent sufficient conditions for the existence of a fuzzy guaranteed cost controller are provided by means of linear matrix inequalities. Some examples are used to illustrate the effectiveness of the proposed method. Copyright © 2007 John Wiley & Sons, Ltd.
Robust delay‐dependent sliding mode control for uncertain time‐delay systems
Authors: Xia Yuanqing , Liu Guo‐Ping , Shi Peng , Chen Jie , Rees David
Published: September 2007

In this paper, the problem of robust sliding mode control for a class of linear continuous time‐delay systems is studied. The parametric uncertainty considered is a modelling error type of mismatch appearing in the state. A delay‐dependent sufficient condition for the existence of linear sliding surfaces is developed in terms of linear matrix inequality, based on which the corresponding reaching motion controller is designed. A numerical example is given to show the potential of the proposed techniques. Copyright © 2007 John Wiley & Sons, Ltd.
Robust adaptive output‐feedback control for nonlinear systems with output unmodeled dynamics
Authors: Wu Zhaojing , Xie Xuejun , Shi Peng
Published: September 2007

In this paper, for a class of uncertain nonlinear systems in the presence of inverse dynamics, output unmodeled dynamics and nonlinear uncertainties, a robust adaptive output‐feedback controller design is proposed by combining small‐gain theorem, changing supply function techniques with backstepping methods. It is shown that all the signals of the closed‐loop system are uniformly bounded in biased case, and the output can be regulated to a small neighborhood of the origin in unbiased case. Furthermore, under some additional assumptions, an asymptotical result is obtained. Copyright © 2007 John Wiley & Sons, Ltd.
Optimal phase I dose‐escalation trial designs in oncology—A simulation study
Authors: Gerke Oke , Siedentop Harald
Published: September 2007

In phase I oncology trials conducted over the past few decades, the maximum tolerated dose (MTD) has usually been estimated by the traditional escalation rule (TER), which traces back to 1973. In the meantime, new methods have been proposed which hope to estimate the true MTD more precisely than the TER while using less patients. In this simulation study, TER is compared with the accelerated titration dose design (ATD), two up‐and‐down designs (biased coin design, r‐in‐a‐row (RIAR)), the maximum likelihood version of the continual reassessment method (CRML), and a Bayesian method that is implemented in the software Bayesian ADEPT (assisted decision‐making in early phase trials). Each design was applied to 50 000 simulated studies. The designs were then compared for accuracy in detecting the true MTD (which is known here), while taking into account the average number of patients and toxicities per run. In terms of accuracy, ADEPT outperformed the
other methods in the scenario with medium toxicity and was close to the best methods in the low and high toxic scenarios. The average number of patients needed per run was the lowest for TER in the scenario with low toxicity and for ADEPT in the remaining scenarios. The longer the escalation path to the target region of the MTD, the more the difference in the average number of patients per run pronounced between TER and ADEPT. TER induced least toxicities in all scenarios. ADEPT turned out to be quick and accurate in determining the MTD, while TER was the safest but least accurate method. CRML was as accurate as TER, and the up‐and‐down designs did not excel. Bayesian ADEPT is considered a valuable tool for the conduct of phase I dose‐escalation trials in oncology, but careful preparation is indispensable before its practical use. Copyright © 2007 John Wiley & Sons, Ltd.
Assessing non‐inferiority of a new treatment in a three‐arm trial in the presence of heteroscedasticity
Authors: Hasler Mario , Vonk Richardus , Hothorn Ludwig A.
Published: September 2007

In this paper, we describe an adjusted method to facilitate non‐inferiority tests in a three‐arm design. While the methodology is readily available in the situation of homogeneous group variances, the adjusted method will also maintain the α‐level in the presence of heteroscedasticity. We propose explicit criteria for an optimal allocation. Depending on the pattern of heterogeneity, remarkably unbalanced designs are power optimal. We will apply the method to a randomized clinical trial and a toxicological experiment. Copyright © 2007 John Wiley & Sons, Ltd.
Memory reconsolidation of cocaine‐associated context requires nitric oxide signaling
Authors: Itzhak Yossef , Anderson Karen L.
Published: September 2007

Recent studies suggest that long‐term memory (LTM) is labile because retrieval of such memories may undergo a reconsolidation process which is vulnerable to disruption. Nitric oxide (NO) is a retrograde messenger involved in synaptic plasticity and LTM. In the present study the role of NO in reconsolidation of LTM of cocaine‐associate context was investigated in wild type (WT) and neuronal nitric oxide synthase (nNOS) deficient mice (knockout; KO). LTM of cocaine‐associated context was established in both WT and nNOS KO mice by conditioned place preference learning. Subsequently, the retrieval of place preference in WT mice was challenged by either saline or the selective nNOS inhibitor 7‐nitroindazole, and retrieval of place preference in KO mice was challenged by either saline or the NO‐donor molsidomine. Results suggest that in the absence of nNOS activity, particularly during the reconsolidation phase, LTM of cocaine‐associated context is extinguished. Synapse 61:1002–1005, 2007. © 2007 Wiley‐Liss, Inc.
The number of dopaminergic cells is increased in the olfactory bulb of monkeys chronically exposed to MPTP
Authors: Belzunegui Silvia , Sebastián Waldy San , Garrido‐Gil Pablo , Izal‐azcárate Amaya , Vázquez‐Claverie Marianne , López Berta , Marcilla Irene , Lanciego José Luis , Luquin Maria Rosario
Published: September 2007

We investigated the impact of the nigrostriatal lesion on the olfactory tyrosine hydroxylase‐immunoreactive (TH‐ir) cells in monkeys. The majority of these TH‐ir cells appeared in the glomerular layer of the olfactory bulb and many were immature but functional dopaminergic neurons. In parkinsonian monkeys the number of olfactory dopaminergic neurons increased up to 100% as compared to controls, but their phenotype did not change. This increased TH‐ir cell population might be a direct consequence of the nigral cell loss and contribute to the hyposmia reported by Parkinson's disease patients.Synapse 61:1006–1012, 2007. © 2007 Wiley‐Liss, Inc.
Publishers as elements of the scientific communication system
Authors: Lucius Wulf D. v.
Published: September 2007

The author argues that the new digital possibilities in scientific communication do not imply, by any means, that many old requirements are becoming dispensable. The essential elements of the system, such as quality assurance, authenticity, orientation and navigation will still demand considerable expense. The overall system costs will rather be higher in a hybrid system. In the second part of his lecture, the author discusses the two fundamentally different open access models, the Golden Road, which is supposed to be able to operate, eventually, without any publishers, and the Green Road, whose functioning is based on primary publication through publishing houses. Finally, the basic issue of the indispensable qualitative stratigraphy of scientific documents is addressed. For this, the published journals, which also provide topical focus and, thus, orientation as well as active marketing in terms of optimal diffusion, still are a very capable tool. It is questionable to what extent these tasks could be fulfilled by university-based repositories. The publishing houses, on the other hand, have a proven track record of providing a wide range of useful value-adding services in digital publishing.
Study of the Additive Effect on the Cloud Point of Nortriptyline Hydrochloride Solutions
Authors: Kabir‐ud‐Din  , Al‐Ahmadi Mohd. D. A. , Naqvi Andleeb Z. , Akram Mohd.
Published: September 2007

The cloud point (CP) phenomenon has been studied in amphiphilic drug nortriptyline hydrochloride solutions with or without additives. The drug solutions were prepared in 10 mM sodium phosphate buffer. An increase in pH decreases the solution CP in the absence as well as the presence of additives (urea and TBuAB) due to deprotonation of the drug molecules. At constant pH (7.07), addition of simple salts (NaF, NaCl, NaBr) increases the CP by increasing the micelle hydration. Addition of Br salts (LiBr, NaBr, KBr) also increases the CP. The behavior is explained on the basis of the cation hydrated radius. Quaternary ammonium bromides, due to adsorption/mixed‐micelle formation, also increase the CP, the order being: Bu<Pr<EtC = O or >C = S moiety. The former interacts with the micelles and decreases CP while the latter (due to its electropositive character) may not interact and hence increases CP.
Suppressor of T‐cell receptor signalling 1 and 2 differentially regulate endocytosis and signalling of receptor tyrosine kinases
Authors: Raguz Josipa , Wagner Sebastian , Dikic Ivan , Hoeller Daniela
Published: September 2007

Suppressor of T‐cell receptor signalling 1 and 2 (Sts‐1 and 2) negatively regulate the endocytosis of receptor tyrosine kinases. The UBA domain of Sts‐2 and SH3‐dependent Cbl‐binding are required for this function. Sts‐1 and ‐2 also possess a PGM domain, which was recently reported to exhibit tyrosine phosphatase activity. Here, we demonstrate that the PGM of Sts‐1, but not of Sts‐2, dephosphorylates the EGFR at multiple tyrosines thereby terminating its signalling and endocytosis. In contrast to Sts‐2 the UBA of Sts‐1 did not contribute significantly to receptor stabilization. Thus, although Sts‐1 and Sts‐2 are structurally highly homologous and both inhibit ligand‐induced EGFR degradation, their mechanisms of action differ significantly. As a consequence, Sts‐1‐containing receptor complexes are inactive, whereas Sts‐2‐containing complexes are signalling competent.
Protein translocation into peroxisomes by ring‐shaped import receptors
Authors: Stanley Will A. , Fodor Krisztian , Marti-Renom Marc A. , Schliebs Wolfgang , Wilmanns Matthias
Published: September 2007

Folded and functional proteins destined for translocation from the cytosol into the peroxisomal matrix are recognized by two different peroxisomal import receptors, Pex5p and Pex7p. Both cargo‐loaded receptors dock on the same translocon components, followed by cargo release and receptor recycling, as part of the complete translocation process. Recent structural and functional evidence on the Pex5p receptor has provided insight on the molecular requirements of specific cargo recognition, while the remaining processes still remain largely elusive. Comparison of experimental structures of Pex5p and a structural model of Pex7p reveal that both receptors are built by ring‐like arrangements with cargo binding sites, central to the respective structures. Although, molecular insight into the complete peroxisomal translocon still remains to be determined, emerging data allow to deduce common molecular principles that may hold for other translocation systems as well.
Developmental effects of perinatal exposure to extremely weak 7 Hz magnetic fields and nitric oxide modulation in the Wistar albino rat
Authors: Whissell P.D. , Persinger M.A.
Published: September 2007

Prenatal exposure of pregnant dams to oscillating magnetic fields can cause behavioural deficits in their offspring which persist into adulthood. These changes are waveform‐specific and may involve nitric oxide. To investigate the interaction between nitric oxide modulation and perinatal magnetic fields, dams were exposed from 2 days before to 14 days after birth to one of six magnetic field conditions (1, 5, 10, 50 or 500 nT or sham) and given either water, 1 g/L nitric oxide precursor l‐arginine or 0.5 g/L nitric oxide synthase inhibitor n‐methylarginine. At weaning (22d), their offspring were placed in the open field for observation. Rats given 50 nT field or 500 nT field + water were hyperactive and showed increased rearing and bodyweight. These strong effects were attenuated or absent in groups given 50 or 500 nT field + n‐methylarginine. Groups given sham field + l‐arginine were behaviourally similar to animals given 50 or 500 nT field + water. Higher intensity fields showed robust behavioural and physiological effects. In general, these effects were counteracted by co‐administration of nitric oxide synthase inhibitor n‐methylarginine, which had little effect on its own. Shams given NO precursor l‐arginine were highly similar to those given any higher intensity magnetic field. Results support a critical developmental role of NO and the involvement of NO in magnetic field effects.
Prenatal hypoxia down regulates the GABA pathway in newborn mice cerebral cortex; partial protection by MgSO4
Authors: Louzoun‐Kaplan Vered , Zuckerman Michal , Regino Perez‐Polo J. , Golan Hava M.
Published: September 2007

The fetal and newborn brain is particularly susceptible to hypoxia, which increases the risk for neurodevelopmental deficits, seizures, epilepsy and life‐span motor, behavioral and cognitive disabilities. Here, we report that prenatal hypoxia at gestation day 17 in mice caused an immediate decrease in fetal cerebral cortex levels of glutamate decarboxylase, a key proteins in the GABA pathway. While maternal MgSO4 treatment prior to hypoxia did not have an early effect, it did accelerate maturation at a later stage based on the observed protein expression profile. In addition, MgSO4 reversed the hypoxia‐induced loss of a subpopulation of inhibitory neurons that express calbindin in cortex at postnatal day 14. In the hippocampus, responses to prenatal hypoxia were also evident 4 days after the hypoxia. However, in contrast to the observations in cerebral cortex, hypoxia stimulated key protein expression in the hippocampus. The hippocampal response to hypoxia was also reversed by maternal MgSO4 treatment. The data presented here suggests that decreased levels of key proteins in the GABA pathway in the cerebral cortex may lead to high susceptibility to seizures and epilepsy in newborns after prenatal or perinatal hypoxia and that maternal MgSO4 treatment can reverse the hypoxia‐induced deficits in the GABA pathway.
Salt‐freshwater dynamics in a subterranean estuary over a spring‐neap tidal cycle
Authors: Robinson C. , Gibbes B. , Carey H. , Li L.
Published: September 2007

This paper presents field measurements and numerical simulations of pore water salinities and groundwater flow in the intertidal zone of an unconfined coastal aquifer over a spring‐neap tidal cycle. The study provides insight into the extent and time‐scales of mixing between fresh groundwater and recirculating seawater in a tidally influenced subterranean estuary. Salt‐freshwater dynamics in subterranean estuaries are currently not well understood despite their potentially important implications for fluxes of chemicals to coastal waters via submarine groundwater discharge. The data and simulation results show that changes in the tidal shoreline excursion over the spring‐neap cycle induce significant variations in the intertidal salinity structure. Observed higher frequency salinity fluctuations demonstrate further the intensity and complexity of the salt‐freshwater mixing process. In contrast with the salinity variations, fresh groundwater was found to discharge around a distinct intertidal beach slope break throughout the spring‐neap period. This suggests that the slope break may affect significantly groundwater flow and salt transport near the shore. Measurements of pH and dissolved oxygen distributions revealed important biogeochemical zonations in the system. These zonations are expected to strongly influence the fate of many reactive chemicals in the nearshore aquifer and their subsequent discharge to coastal waters.