bluuebunny/crossref_metadata_2025 huggingface dataset:
Java applets for viewing one‐ and two‐dimensional NMR spectra
Authors: Sharman Gary J.
Published: August 2006

Two Java applets, which allow viewing and simple reprocessing operations of one‐ and two‐dimensional NMR spectra from within a web page, are described. For the 1D viewer, phasing, integration, peak picking and referencing are supported. Bruker, Varian and JCAMP‐DX processed data files can be opened. The 2D viewer allows f2 phasing and referencing, and can read native Bruker processed data. The compiled applets are available from the author on request. Copyright © 2006 John Wiley & Sons, Ltd.
Halogen – metal exchange of 3‐substituted 1,2‐dibromoarenes: the use of long‐range JCH coupling constants to determine regiochemistry
Authors: DiMichele Lisa , Menzel Karsten , Mills Paul , Frantz Doug , Nelson Todd
Published: August 2006

Regioselective halogen/metal exchange reactions were carried out on a series of 3‐substituted‐ 1,2‐dibromoarenes. Product mixtures were quenched with CO2 to form the corresponding benzoic acid analogs to facilitate HPLC and NMR analysis. Substitution at the 3‐position could readily be assigned on the basis of 2D HMBC long‐range correlations, while assignment at the 2‐position was not as straightforward. The use of three‐bond JCH coupling constant measurements, extracted from 1‐D 1H coupled 13C experiments, were necessary to render unequivocal regio assignments. Copyright © 2006 John Wiley & Sons, Ltd.
Cloning of Asian yellow goat (C. hircus) by somatic cell nuclear transfer: Telophase enucleation combined with whole cell intracytoplasmic injection
Authors: Chen Da‐Yuan , Jiang Man‐Xi , Zhao Zhen‐Jun , Wang Hai‐Long , Sun Qing‐Yuan , Zhang Li‐Sheng , Li Rui‐Chang , Cao Heng‐Hua , Zhang Quan‐Jun , Ma Dong‐Lian
Published: August 2006

Our and other previous studies have shown that telophase enucleation is an efficient method for preparing recipient cytoplasts in nuclear transfer. Conventional methods of somatic cell nuclear transfer either by electro‐fusion or direct nucleus injection have very low efficiency in animal somatic cell cloning. To simplify the manipulation procedure and increase the efficiency of somatic cell nuclear transfer, this study was designed to study in vitro and in vivo development of Asian yellow goat cloned embryos reconstructed by direct whole cell intracytoplasmic injection (WCICI) into in vitro matured oocytes enucleated at telophase II stage. Our results demonstrated that the rates of cleavage and blastocyst development of embryos reconstructed by WCICI were slightly higher than in conventional subzonal injection (SUZI) group, but no statistic difference (P > 0.05) existed between these two methods. However, the percentage of successful embryonic reconstruction in WCICI group was significantly higher than that in SUZI group (P < 0.05). After embryo transfer at 4‐cell stage, the foster in both groups gave birth to offspring. Therefore, the present study suggests that the telophase ooplasm could properly reprogram the genome of somatic cells, produce Asian yellow goat cloned embryos and viable kids, and whole cell intracytoplasmic injection is an efficient protocol for goat somatic cell nuclear transfer. Mol. Reprod. Dev. 74: 28–34, 2007. © 2006 Wiley‐Liss, Inc.
Motor unit number estimates correlate with strength in polio survivors
Authors: Sorenson Eric J. , Daube Jasper R. , Windebank Anthony J.
Published: August 2006

Motor unit number estimation (MUNE) has been proposed as an outcome measure in clinical trials for the motor neuron diseases. One major criticism of MUNE is that it may not represent a clinically meaningful endpoint. We prospectively studied a cohort of polio survivors over a period of 15 years with respect to MUNE and strength. We identified a significant association between thenar MUNE and arm strength, extensor digitorum brevis MUNE and leg strength, and the summated MUNE and global strength of the polio survivors. These findings confirm the clinical relevance of MUNE as an outcome measure in the motor neuron diseases and provide further validation for its use in clinical trial research. Muscle Nerve, 2006
Effects of hypoxia on muscle response to tendon vibration in humans
Authors: Delliaux Stéphane , Jammes Yves
Published: August 2006

Previous animal studies have shown that hypoxia markedly reduces the activation of muscle spindles. The present study was undertaken to determine whether a reduced oxygen supply to muscle affects the tonic vibration reflex (TVR) in humans. In resting healthy volunteers, the effects of inhalation of hypoxic gas, apnea, and total forearm ischemia produced by cuff inflation were studied on separate days. The TVR was recorded in flexor digitorum superficialis and the neuromuscular conduction time (CT) was measured from the compound muscle action potential; the latency and amplitude of the H reflex were also determined. TVR depression began during inhalation of the hypoxic gas, at the end of apnea, and during cuff inflation, and persisted during the recovery period. The H‐reflex amplitude concomitantly increased or remained unchanged. Thus, hypoxia seems to directly alter muscle spindle reactivity. Such alterations of sensorimotor control may occur in patients suffering from respiratory or circulatory insufficiency and may contribute to their exercise limitation. Muscle Nerve, 2006
A new analytical method to diagnose congenital myasthenia with stimulated single‐fiber electromyography
Authors: Tidswell Thomas , Pitt Matthew C.
Published: August 2006

Stimulated single‐fiber electromyography (SSF‐EMG) is useful to assess neuromuscular junction (NMJ) abnormalities in children. Conventionally mean consecutive difference (MCD) analysis measures the jitter for each muscle‐fiber potential. We present a new algorithm that analyzes the entire SSF‐EMG waveform. Cross‐correlational coefficients (between 0–1.0) are calculated for consecutive pairs of 100 SSF‐EMG waveforms obtained at each needle position in orbicularis oculi, and averaged. A lower normal limit (0.722, mean −3 SD) was established from 123 SSF‐EMG samples in 10 adult control subjects, and applied to SSF‐EMG data from 23 children referred for a suspected myasthenic syndrome. Results were compared with MCD analysis and related to the final clinical diagnosis. Our results showed that compared with conventional MCD measurement, the new algorithm had better specificity (87% vs. 53%) but similar sensitivity (88% for both). These findings indicate that the cross‐correlational method is a useful predictor of NMJ dysfunction in children. Muscle Nerve, 2006
External anal sphincter responses after S3 spinal root surface electrical stimulation
Authors: Pelliccioni Giuseppe , Scarpino Osvaldo
Published: August 2006

Aims

The aim of this study is to present the normative data of direct and reflex motor anal sphincter responses, simultaneously evoked by S3 surface electrical stimulation. By this method, it is possible to test the functional integrity of the nervous pathways activated during sacral neuromodulation (SNM).

Methods

Twenty healthy subjects were studied. Motor‐evoked potentials (MEPs) were recorded by concentric needle electrode from external anal sphincter (EAS). Electrical stimulation was applied by means of a bipolar surface electrode over the S3 right or left sacral foramina.

Results

Direct (R1) and reflex responses (R2 and R3) were found at latencies of 6.98, 25.12, and 50.31 msec, respectively. The two first responses were recorded in all the cases; the last response is steadily recorded in 17 out of 20 subjects.

Conclusions

Our data can serve as reference values for future study in patients with pelvic floor dysfunction. EAS responses following S3 percutaneous electrical stimulation can represent a useful aid in the selection of candidates to SNM. Neurourol. Urodynam. 25:788–791, 2006. © 2006 Wiley‐Liss, Inc.
Alternately linearized implicit iteration methods for the minimal nonnegative solutions of the nonsymmetric algebraic Riccati equations
Authors: Bai Zhong‐Zhi , Guo Xiao‐Xia , Xu Shu‐Fang
Published: August 2006

For the non‐symmetric algebraic Riccati equations, we establish a class of alternately linearized implicit (ALI) iteration methods for computing its minimal non‐negative solutions by technical combination of alternate splitting and successive approximating of the algebraic Riccati operators. These methods include one iteration parameter, and suitable choices of this parameter may result in fast convergent iteration methods. Under suitable conditions, we prove the monotone convergence and estimate the asymptotic convergence factor of the ALI iteration matrix sequences. Numerical experiments show that the ALI iteration methods are feasible and effective, and can outperform the Newton iteration method and the fixed‐point iteration methods. Besides, we further generalize the known fixed‐point iterations, obtaining an extensive class of relaxed splitting iteration methods for solving the non‐symmetric algebraic Riccati equations. Copyright © 2006 John Wiley & Sons, Ltd.
Level‐Sets fields, placement and velocity based formulations of contact‐impact problems
Authors: Dhia Hachmi Ben , Zammali Chokri
Published: August 2006

By introducing unknown Sign‐like fields of Level‐Sets type, the Signorini‐Moreau dynamic contact conditions are set merely as boundary equations. From this setting, a continuous hybrid weak–strong formulation for dynamic contact between deformable solids is derived and a new Lagrangian formulation (we call stabilized) generalizing both the classical and augmented ones is obtained. Friction phenomena are treated similarly. In the global problem, the irregular Sign‐like fields stand for the intrinsic contact unknown ones. This problem is discretized by means of time, space and collocation schemes. Some numerical experimentations are carried out, showing the potential of our developments. Copyright © 2006 John Wiley & Sons, Ltd.
Cleft palate: a case study of disability and survival in prehistoric North America
Authors: Phillips S. M. , Sivilich M.
Published: August 2006

This study presents an analysis of an adult male that demonstrates diagnostic markers of cleft palate. The burial is associated with the Grider Site, Late Woodland context (AD 500 to 1000), located in Pike County, Indiana, USA. The analysis draws on clinical and palaeopathology literature to consider other possible conditions responsible for the skeletal anomalies. Cleft palate occurs in about one in 1000 live births, and is one of the most common defects of the face. Despite the high frequency of cleft palate, few cases are reported from the archaeological record. It is possible that, in the past, few infants survived extreme forms of cleft palate, and such cases are not present to be recorded. Or, it is possible that the lesion simply goes undocumented. This analysis outlines the markers of cleft palate in this individual and demonstrates that a prehistoric culture could overcome the health issues experienced by an infant with the condition (full communication between the oral and nasal cavities) and survive to adulthood. Copyright © 2006 John Wiley & Sons, Ltd.
Skeletal evidence for hyperparathyroidism in a 19th century child with rickets
Authors: Mays S. , Brickley M. , Ives R.
Published: August 2006

The skeletal remains of a child aged 2.5–3.5 years, recovered during archaeological excavations at the churchyard of St Martin's Church, Birmingham, UK, were examined using gross observation, radiography and scanning electron microscopy. Lesions suggestive of the presence of rickets and of secondary hyperparathyroidism were found. This appears to be a first report of secondary hyperparathyroidism in response to rickets in a palaeopathological specimen. The potential of microscopic examination of bone for interpreting disease processes is emphasised. Copyright © 2006 John Wiley & Sons, Ltd.
Gain of 1q25–32, 12q23–24.3, and 17q12–22 facilitates tumorigenesis and progression of human squamous cell lung cancer
Authors: Ma J , Gao M , Lu Y , Feng X , Zhang J , Lin D , Xiao T , Hu Z , Yuan J , Su K , Shipley J , Xue J , Gao Y
Published: August 2006

To explore the genetic changes involved in the stepwise development of lung cancer, we have determined the genetic events associated with the histological progression from normal bronchial epithelium to squamous cell carcinoma. Comparative genomic hybridization was used to identify chromosomal imbalances in 54 microdissected samples, including squamous metaplasia, dysplasia, carcinoma in situ, and invasive tumour derived from 23 patients with squamous cell carcinoma of the lung. Histopathological progression was accompanied by an increased number of chromosomal abnormalities. Gains of 1q25–32, 12q23–24.3, and 17q12–22, in particular, were detected at high frequencies in both carcinoma in situ and invasive tumours and were found more often in the cases with lymph node metastases than in those without. Our previous expression profiling of squamous cell carcinomas had identified overexpression of laminin5 γ2, a gene located at 1q25–31. Therefore, this was investigated at the protein level by immunohistochemical analysis in 336 samples of squamous cell carcinoma of the lung. Consistent with the genomic data for this region, the expression level of laminin5 γ2 was higher in the primary tumours with lymph node metastases than in tumours without metastases (p = 0.012). These data suggest that gains of genes from 1q25–32, 12q23–24.3, and 17q12–22 facilitate tumorigenesis and progression of squamous cell carcinoma of the lung, and may serve as potential predictors for this disease. Copyright © 2006 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Mobilization of Ph chromosome‐negative peripheral blood stem cells in a child with chronic myeloid leukemia after imatinib‐induced complete molecular remission
Authors: Woods‐Swafford Wendy , Vnencak‐Jones Cindy L. , Loken Michael R. , Manes Becky , Frangoul Haydar
Published: August 2006

Chronic myelogenous leukemia (CML) is rare in the pediatric population. Allogeneic stem cell transplant remains the only curative therapy; however, identifying a fully matched donor is not always possible. Imatinib mesylate has been shown to induce hematologic and cytogenetic response in adults and children with CML. We describe a child who achieved molecular remission with imatinib mesylate. BCR‐ABL negative peripheral blood stem cells (PBSC) were successfully collected after mobilization with filgrastim. Pediatr Blood Cancer 2008;50:639–641. © 2006 Wiley‐Liss, Inc.
A high‐throughput monolithic HPLC method for rapid Vitamin C phenotyping of berry fruit
Authors: Walker Paul G. , Gordon Sandra L. , Brennan Rex M. , Hancock Robert D.
Published: August 2006

A rapid method for the quantification of łascorbic acid (1) in berry fruit by HPLC with photodiode array detection is presented. łAscorbic acid was resolved on a C18 monolithic column with aqueous buffer, after which the column was washed with acetonitrile to remove lipophilic compounds prior to re‐equilibration for analysis of the next sample. Using the monolithic column format with high mobile phase flow rates, the entire separation, wash and re‐equilibration were achieved in 3 min. With the exception of gooseberry (Ribes uva‐crispa), for which an interfering compound co‐eluted, concentrations of 1 could be determined in a wide range of berry fruits after extraction in metaphosphoric acid without further sample preparation. Using this extraction method, recoveries of 1 in excess of 85% were achieved. Fruit or juice extracts were stable in 5% metaphosphoric acid for at least 4 h and stability could be extended to longer than 150 h by the addition of the reducing agent tris(2‐carboxethyl)phosphine hydrochloride. Following validation, the method was utilised for the phenotyping of fruit in a Scottish Crop Research Institute (SCRI) Ribes nigrum L. breeding population of 300 individuals. An improved extraction method allowed extraction, quantification of 1 and data analysis to be undertaken in less than one working week. Copyright © 2006 John Wiley & Sons, Ltd.
Perception of potentially inappropriate medication in elderly patients by Slovak physicians
Authors: Wawruch M. , Zikavska M. , Wsolova L. , Jezova D. , Fialova D. , Kunzo M. , Kuzelova M. , Lassanova M. , Kruty P. , Kriska M.
Published: August 2006

Purpose

The aim of the present study was to determine the risk perception of potentially inappropriate drug treatment of elderly patients by Slovak physicians. In Slovakia, a list of such drugs is not available.

Methods

The study sample consisted of 600 patients aged ≥65 years hospitalized at the Department of Internal Medicine in a Slovak general hospital between 1 December 2003 and 31 March 2005. The use of potentially inappropriate drugs at the time of hospital admission and discharge was compared. Potentially inappropriate drug use was defined by Beers 2003 criteria. In addition, 206 physicians were asked to mark the drugs that they considered potentially inappropriate for elderly patients out of a list provided in a questionnaire analysis.

Results

Out of 600 patients 20.2% and 20% were treated with at least one potentially inappropriate drug at the time of hospital admission and discharge, respectively. Hospitalization had no significant influence on the number of potentially inappropriate medicines used. The most frequently prescribed potentially inappropriate drugs were digoxin >0.125 mg/day and ticlopidine. Out of 206 responding physicians only 4.9% considered ticlopidine as potentially inappropriate for elderly patient. On the other hand, more than 20% of respondents were aware of the potential inappropriateness of amitriptyline, diazepam and chlordiazepoxide. Mentioned drugs were observed in less than 2% of study population (n = 600).

Conclusions

The results of the questionnaire analysis in physicians as well as the prevalence of potentially inappropriate medication demonstrate that Slovak clinicians are aware of the risk of certain treatments in elderly patients. Copyright © 2006 John Wiley & Sons, Ltd.
Investigation of the relaxation behavior of novel terpolymers of acrylonitrile, methyl methacylate and indene
Authors: Mohammady Sayed Z , Elkholy Said S , Elsabee Maher Z
Published: August 2006

Terpolymer samples were prepared by free radical polymerization of methyl methacrylate (MMA), indene (In) and acrylonitrile (AN) in bulk. The samples were chosen so that the molar ratio of AN to MMA varied from 1.00:4.39 to 1.00:0.83, while the molar ratio of In was kept almost unchanged. The glass transition temperatures (Tg) of the samples were determined using differential scanning calorimetry. Moreover, isochronal dynamic mechanical measurements of the complex bending modulus as well as the complex dielectric permittivity were carried out over wide temperature ranges, namely from 50 to 190 °C, depending on the material investigated. All samples exhibited a single common Tg value, which increased to higher temperature upon increasing the content of AN. In addition, the results were investigated quantitatively in the framework of a molecular model. Copyright © 2006 Society of Chemical Industry
p‐Nitrobenzyltriphenyl phosphonium ylide‐initiated radical terpolymerization of styrene, methyl methacrylate and acrylonitrile: synthesis, characterization and properties
Authors: Prajapati Kiran , Varshney Anuradha
Published: August 2006

Solution terpolymerization of styrene (St), methyl methacrylate (MMA) and acrylonitrile (AN) was carried out in dioxane at 65 ± 0.1 °C for 120 min using p‐nitrobenzyltriphenyl phosphonium ylide as radical initiator. The kinetic expression is as follows (Rp is the rate of polymerization): Rp∝ [ylide]0.45[St]0.8[MMA]1.2[AN]1.2. The overall activation energy is 42 kJ mol−1 L−1. The composition of terpolymer, calculated from 1H NMR and elemental analysis, was used to evaluate reactivity ratio, as r1 (MMA + AN) = 0.06 and r2 (St) = 0.005, employing the Kelen–Tüdos method. It confirmed the alternating nature of the terpolymer. The terpolymer was characterized using 13C NMR, gel permeation chromatography and thermogravimetric differential thermal analysis. Electron spin resonance spectroscopy confirmed the presence of the phenyl radical responsible for initiation. Copyright © 2006 Society of Chemical Industry
A simple chemical approach to the production of nano‐sized crystals of poly(acrylic acid)
Authors: Wang Ge , Cai Fuli , Yang Mu , Si Lichun , Wang Zhiqiang , Duan Xue
Published: August 2006

A new approach is proposed which is shown to be a feasible method for the production of nano‐sized polymer crystals of poly(acrylic acid). The new approach involves in situ polymerization of acrylic acid in the interlayers of layered double hydroxides, followed by exchange of the polymer anions for carbonate. The key is the use of a layered double hydroxide as a template. Copyright © 2006 Society of Chemical Industry
Non‐covalent interaction of 2', 4', 5', 7'‐tetrabromo‐4, 5, 6, 7‐tetrachlorofluorescein with proteins and its application
Authors: Gao Hong‐Wen , Zhao Jian‐Fu , Yang Qiao‐Zhi , Liu Xiang‐Hu , Chen Ling , Pan Lu‐Ting
Published: August 2006

The interactions of 2', 4', 5', 7'‐tetrabromo‐4, 5, 6, 7‐tetrachlorofluorescein (TBTCF) with BSA, ovalbumin (OVA) and poly‐L‐lysine (PLYS) at pH 3.70 have been investigated by combination of the spectral correction technique and the Langmuir isothermal adsorption. The active connection actions such as ion pairs, van der Waals' force, hydrogen bond, hydrophobic bond were proposed to explain the non‐covalent interaction between TBTCF and BSA, OVA and PLYS. Effects of the electrolyte and high temperature indicated that union of the active connections between TBTCF and BSA and OVA was too firm to be destroyed. The relationship between the binding number of TBTCF and variety fraction of the amino acid residues was analyzed. The binding number of TBTCF depended on the number of positively charged amino acid residues. The other amino acid residues surrounded and seized TBTCF by hydrogen bonds and hydrophobic bonds when the electrostatic attraction pulled TBTCF to link protein. In addition, a novel method named the absorbance ratio difference was established for determination of protein in trace level and was applied with much higher sensitivity than the ordinary method.
Analysis of the HUPO Brain Proteome reference samples using 2‐D DIGE and 2‐D LC‐MS/MS
Authors: Fröhlich Thomas , Helmstetter Derrick , Zobawa Monica , Crecelius Anna C. , Arzberger Thomas , Kretzschmar Hans A. , Arnold Georg J.
Published: August 2006

Within the Human Proteome Organization (HUPO) Brain Proteome Project, a pilot study was launched with reference samples shipped to nine international laboratories (see Hamacher et al., this Special Issue) to evaluate different proteome approaches in neuroscience and to build up a first version of a brain protein database. One part of the study addresses quantitative proteome alterations between three developmental stages (embryonic day 16; postnatal day 7; 8 weeks) of mouse brains. Five brains per stage were differentially analyzed by 2‐D DIGE using internal standardization and overlapping pH gradients (pH 4–7 and 6–9). In total, 214 protein spots showing stage‐dependent intensity alterations (>two‐fold) were detected, 56 of which were identified. Several of them, e.g. members of the dihydropyrimidinase family, are known to be associated with brain development. To feed the HUPO BPP brain protein database, a robust 2‐D LC‐MS/MS method was applied to murine postnatal day 7 and human post‐mortem brain samples. Using MASCOT and the IPI database, 350 human and 481 mouse proteins could be identified by at least two different peptides. The data are accessible through the PRIDE database (http://www.ebi.ac.uk/pride/).
Examination of 2‐DE in the Human Proteome Organisation Brain Proteome Project pilot studies with the new RAIN gel matching technique
Authors: Dowsey Andrew W. , English Jane , Pennington Kyla , Cotter David , Stuehler Kai , Marcus Katrin , Meyer Helmut E. , Dunn Michael J. , Yang Guang‐Zhong
Published: August 2006

The Human Proteome Organisation (HUPO) Brain Proteome Project (BPP) pilot studies have generated over 200 2‐D gels from eight participating laboratories. This data includes 67 single‐channel and 60 DIGE gels comparing 30 whole frozen C57/BL6 female mouse brains, ten each at embryonic day 16, postnatal day 7 (juvenile) and postnatal day 54–56 (adult); and ten single‐channel and three DIGE gels comparing human epilepsy surgery of the temporal front lobe with a corresponding post‐mortem specimen. The samples were generated centrally and distributed to the participating laboratories, but otherwise no restrictions were placed on sample preparation, running and staining protocols, nor on the 2‐D gel analysis packages used. Spots were characterised by MS and the annotated gel images published on a ProteinScape web server. In order to examine the resultant differential expression and protein identifications, we have reprocessed a large subset of the gels using the newly developed RAIN (Robust Automated Image Normalisation) 2‐D gel matching algorithm. Traditional approaches use symbolic representation of spots at the very early stages of the analysis, which introduces persistent errors due to inaccuracies in spot modelling and matching. With RAIN, image intensity distributions, rather than selected features, are used, where smooth geometric deformation and expression bias are modelled using multi‐resolution image registration and bias‐field correction. The method includes a new approach of volume‐invariant warping which ensures the volume of protein expression under transformation is preserved. An image‐based statistical expression analysis phase is then proposed, where small insignificant expression changes over one gel pair can be revealed when reinforced by the same consistent changes in others. Results of the proposed method as applied to the HUPO BPP data show significant intra‐laboratory improvements in matching accuracy over a previous state‐of‐the‐art technique, Multi‐resolution Image Registration (MIR), and the commercial Progenesis PG240 package.
Kinetic and mechanistic studies on sulfamate esters: models of enzyme inhibitors
Authors: McCaw Cheryl J. A. , Spillane William J.
Published: August 2006

Many compounds containing a sulfamate moiety, such as NH2SO2O are now known to be medicinally important. However, very little is known about their mechanisms of reaction even under non‐biological conditions. In this work the various types of elimination mechanisms that may occur have been probed by studying the kinetics of the reactions of model sulfamate substrates with amines (bases) that act as models for the enzymes involved. The principal mechanistic tool employed has been Brönsted plots and both ‘normal’ rectilinear and two types of biphasic plots have been found for the decomposition of the esters in acetonitrile (ACN). The mechanisms operating are seen as being of the E2 and E1cB types. Copyright © 2006 John Wiley & Sons, Ltd.
Synthesis, characterization, and electrical properties of a diazodiphenylene‐bridged Cu–phthalocyanine polymer
Authors: Alkan Cemil , Aras Leyla , Gündüz Güngör
Published: August 2006

A diazodiphenylene‐bridged Cu–phthalocyanine polymer was synthesized from the diazonium salt of bensidine and the Cu(II) 1,8,15,22‐tetraaminophthalocyanine complex and characterized with Fourier transform infrared, ultraviolet–visible spectroscopy, and elemental analysis. The polymer was partially soluble in organic solvents such as dimethylformamide and tetrahydrofuran. The molecular weight of the soluble part of the polymer was investigated with ebullioscopy and viscosimetry methods in tetrahydrofuran. Both methods showed that the molecular weight of the polymer was much larger than that of the complex. The conductivity of the samples was measured with a four‐prop conductivity measuring device. Iodine and hydrogen chloride were doped to the polymer, and an increase of about 104 S cm−1 in the electrical conductivity was observed. The cyclic voltammogram of the diazodiphenylene‐bridged Cu–phthalocyanine polymer in contact with a LiClO4 electrolyte exhibited two reductions and two reoxidations with high reversibility and electrochemical stability. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 5692–5698, 2006
New environmentally responsive fluorescent N‐isopropylacrylamide copolymer and its application to DNA sensing
Authors: Yang Chang‐Chung , Tian Yanqing , Jen Alex K.‐Y. , Chen Wen‐Chang
Published: August 2006

We report two novel multifunctional copolymers consisting of a temperature‐responsive poly(N‐isopropylacrylamide) (PNIPAA) segment and a fluorescent fluorene‐containing acrylic polymer segment with pH responsiveness and/or DNA‐sensing ability. The functional acrylic monomer with a fluorene dimer side group substituted with amino units was synthesized first. Then, it was copolymerized with N‐isopropylacrylamide to result in a new water‐soluble, fluorescent PNIPAA copolymer (P1). The fluorescent properties of P1 under neutral and acidic conditions did not change with the temperature. However, significant variation was observed under basic conditions. The protonation of the amino moiety at a low pH improved the solubility and prevented aggregation for fluorescence quenching, but not under the basic conditions. Although aggregation of the fluorene units was significant at room temperature under basic conditions, the aggregation was resolved at a temperature above the lower critical solution temperature. These findings indicated the pH‐ and temperature‐responsive characteristics of P1. Moreover, after the amino groups were quaternized, the obtained polymer could be used as a biosensor because the fluorescence intensity was quenched with the addition of DNA. This study demonstrates that multifunctional materials with pH‐ and temperature‐sensing characteristics and biological molecules could be realized by the incorporation of a functional fluorene‐containing moiety with PNIPAA. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 5495–5504, 2006
ABC‐type hetero‐arm star terpolymers through “Click” chemistry
Authors: Altintas Ozcan , Hizal Gurkan , Tunca Umit
Published: August 2006

Hetero‐arm star ABC‐type terpolymers, poly(methyl methacrylate)‐polystyrene‐poly(tert‐butyl acrylate) (PMMA‐PS‐PtBA) and PMMA‐PS‐poly(ethylene glycol) (PEG), were prepared by using “Click” chemistry strategy. For this, first, PMMA‐b‐PS with alkyne functional group at the junction point was obtained from successive atom transfer radical polymerization (ATRP) and nitroxide‐mediated radical polymerization (NMP) routes. Furthermore, PtBA obtained from ATRP of tBA and commercially available monohydroxyl PEG were efficiently converted to the azide end‐functionalized polymers. As a second step, the alkyne and azide functional polymers were reacted to give the hetero‐arm star polymers in the presence of CuBr/N,N,N′,N″,N″‐pentamethyldiethylenetriamine (PMDETA) in DMF at room temperature for 24 h. The hetero‐arm star polymers were characterized by 1H NMR, GPC, and DSC. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 5699–5707, 2006
Effect of excess halide on the palladium‐catalyzed insertion‐triggered radical copolymerization of methyl acrylate and 1‐hexene
Authors: Albéniz Ana C. , Espinet Pablo , López‐Fernández Raquel
Published: August 2006

[Pd2(μ‐Cl)2(C6F5)2(tht)2] (1) is a very efficient initiator of the radical polymerization of methyl acrylate, but it is not active in the polymerization of methyl methacrylate or in the copolymerization with 1‐hexene. The addition of an excess of NBu4Cl to solutions of [Pd2(μ‐Cl)2(C6F5)2(tht)2] (1) provides an initiator system that copolymerizes methyl acrylate and 1‐hexene by an insertion‐triggered radical mechanism. Random copolymers are obtained with 11% incorporation of 1‐hexene in moderate yields (about 35%). Studies of the decomposition products obtained after the first insertion of methyl acrylate in the PdC6F5 bond of 1 show that the addition of excess halide in the presence of monomer favors the homolytic cleavage of the PdC bond, and the generation of the radicals that are active species in the polymerization, versus alternative evolution pathways. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 5682–5691, 2006
Reversible‐addition fragmentation chain transfer radical emulsion polymerization by a nanoprecipitation process
Authors: Szkurhan Andrea R. , Kasahara Takahito , Georges Michael K.
Published: August 2006

Polymerizations of styrene under emulsion reversible‐addition fragmentation chain transfer polymerization conditions are reported. Using a recently developed nanoprecipitaiton process, emulsion particles were formed by the precipitation of an acetone solution of a macroRAFT agent into an aqueous solution of poly(vinyl alcohol). The particles were then swollen with monomer and subsequently polymerized. Emulsion polymerizations were performed at 65 and 75 °C in which either KPS, BPO, or a combination of both was used as an initiating source. Reactions were also performed at temperatures over 100 °C in which the thermal initiation of styrene was used as an initiating source. In all cases, the polymerizations proceeded in a living manner, yielding polymers that showed an incremental increase in molecular weight with time and had narrow molecular weight distributions. Plots of number‐ average molecular weight versus conversion were linear, indicating a controlled polymerization. The resulting latices were colloidally stable and gave particle size distributions with a typical average particle diameter in the 150 nm range. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 5708–5718, 2006
α,α‐Dibromotoluene as a monomer for poly (substituted methylene) synthesis: Magnesium‐mediated polycondensation of α,α‐dibromotoluene and magnesium/copper‐mediated copolycondensation of α,α‐dibromotoluene with 1,6‐dibromohexane
Authors: Ihara Eiji , Wake Takao , Mokume Naoki , Itoh Tomomichi , Inoue Kenzo
Published: August 2006

α,α‐Dibromotoluene 1 was found to be polymerized by the reaction with excess Mg to give poly(phenylmethylene)s 2, whose main chains were partially dehydrogenated to carbon–carbon double bonds (CC). The CCs in 2 can be brominated by treatment with Br2. The polymerization mechanism was presumed to include the formation of Grignard reagents of various species with benzylic CBr bonds and the nucleophilic attacks of the Grignard reagents to various compounds with benzylic CBr bonds. Copolymerization of 1 with dichlorodimethylsilane successfully proceeded. Mg/Cu‐mediated copolycondensation of 1 with 1,6‐dibromohexane proceeded to give polymers that have similar compositions to those of random copolymers of ethylene and styrene. © 2006Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 5661–5671, 2006
Synthesis and characterization of a new disubstituted polyacetylene containing indolylazo moieties in side chains
Authors: Li Zhen , Li Qianqian , Qin Anjun , Dong Yongqiang , Lam Jacky W. Y. , Dong Yuping , Ye Cheng , Qin Jingui , Tang Ben Zhong
Published: August 2006

A new disubstituted polyacetylene with indolylazo moieties in its side chains (9) was synthesized by a post functionalization strategy, which was difficult, or perhaps impossible, to obtain from the direct polymerization of its corresponding monomer. The polymer is soluble in common solvents and thermally stable. The polymer shows good optical transparency with an absorption maximum at 393 nm and a band edge at ∼530 nm. Its poled film exhibits a resonant d33 value of 17.9 pm/V and its optical nonlinearity is resistant to thermal decay at up to 147 °C. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 5672–5681, 2006
Flame retardant epoxy resins based on diglycidyloxymethylphenylsilane
Authors: Mercado L. A. , Reina J. A. , Galià M.
Published: August 2006

Silicon‐containing epoxy resins were prepared from diglycidyloxymethylphenyl silane (DGMPS) and diglycidylether of bisphenol A (DGEBA) by crosslinking with 4,4′‐diaminodiphenylmethane (DDM). Several DGMPS/DGEBA molar ratios were used to obtain materials with different silicon contents. Their thermal, dynamomechanical, and flame‐retardant properties were evaluated and related to the silicon content. The weight loss rate of the silicon‐containing resins is lower than that of the silicon free resin. Char yields under nitrogen and air atmospheres increase with the silicon content. The LOI (limited oxygen index) values increased from 24 for a standard commercial resin to 36 for silicon‐containing resins, demonstrating improved flame retardancy. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 5580–5587, 2006
Comparison of Atmospheric‐Pressure Plasma versus Low‐Pressure RF Plasma for Surface Functionalization of PTFE for Biomedical Applications
Authors: Sarra‐Bournet Christian , Turgeon Stephane , Mantovani Diego , Laroche Gaetan
Published: August 2006

Summary: PTFE surface modifications have been realized using low‐pressure RFGD, DBD and APGD in different atmospheres. Compared to the RFGD NH3 plasma, the DBDs operating in H2/N2 lead to similar surface concentrations of amino groups and similar surface damage, but with a much higher specificity. Both APGDs in H2/N2 and NH3/N2 lead to lower concentrations of amino groups, but with similar specificity, and with lower surface damage than the RFGD treatment. A method is proposed to evaluate the efficiency of the different discharges for amine surface functionalization of PTFE, and it is concluded that the NH3/N2 APGD discharge is the one that give the best results for an effective surface treatment.

Experimental setups for the DBD and the APGD plasma systems.

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Experimental setups for the DBD and the APGD plasma systems.
Optimal design of clinical trials comparing several treatments with a control
Authors: Marschner Ian C.
Published: August 2006

Clinical trials are often designed to compare several treatments with a common control arm in pairwise fashion. In this paper we study optimal designs for such studies, based on minimizing the total number of patients required to achieve a given level of power. A common approach when designing studies to compare several treatments with a control is to achieve the desired power for each individual pairwise treatment comparison. However, it is often more appropriate to characterize power in terms of the family of null hypotheses being tested, and to control the probability of rejecting all, or alternatively any, of these individual hypotheses. While all approaches lead to unbalanced designs with more patients allocated to the control arm, it is found that the optimal design and required number of patients can vary substantially depending on the chosen characterization of power. The methods make allowance for both continuous and binary outcomes and are illustrated with reference to two clinical trials, one involving multiple doses compared to placebo and the other involving combination therapy compared to mono‐therapies. In one example a 55% reduction in sample size is achieved through an optimal design combined with the appropriate characterization of power. Copyright © 2006 John Wiley & Sons, Ltd.
Sample size calculation for the Power Model for dose proportionality studies
Authors: Sethuraman Venkat S. , Leonov Sergei , Squassante Lisa , Mitchell Toni R. , Hale Michael D.
Published: August 2006

There are several approaches to assess or demonstrate pharmacokinetic dose proportionality. One statistical method is the traditional ANOVA model, where dose proportionality is evaluated using the bioequivalence limits. A more informative method is the mixed effects Power Model, where dose proportionality is assessed using a decision rule for the estimated slope. Here we propose analytical derivations of sample sizes for various designs (including crossover, incomplete block and parallel group designs) to be analysed according to the Power Model. Copyright © 2006 John Wiley & Sons, Ltd.
In vitroanthelmintic activity ofMelia azedarachnaturalized in Argentina
Authors: Szewczuk Víctor D. , Mongelli Elena R. , Pomilio Alicia B.
Published: August 2006

The anthelmintic activity of the drupe extracts ofMelia azedarachL. (Meliaceae) growing in Argentina was tested against tapeworms, hookworms, nodular worms and earthworms, and was shown to be better than the standards piperazine phosphate and hexylresorcinol against tapeworms and hookworms, respectively. Copyright © 2006 John Wiley & Sons, Ltd.
Study on the Structure‐Activity Relationship of New Anti‐HIV Nucleoside Derivatives Based on the Support Vector Machine Method
Authors: Wang Jie , Liu Huanxiang , Qin Shen , Yao Xiaojun , Liu Mancang , Hu Zhide , Fan Botao
Published: August 2006

Support Vector Machine (SVM) was used for the classification of the activity of the new anti‐HIV nucleosides derivatives for a large and diverse data set using the twelve descriptors that were calculated from the molecular structure alone. The molecular descriptors were selected by the stepwise Linear Discriminant Analysis (LDA) method implemented in SPSS. The correlation between all the descriptors was lower than 0.85. At the same time, in order to build a nonlinear model to classify the new anti‐HIV drugs according to their activities, the data set was divided into two subgroups: the training set and the testing set. The nonlinear model gives satisfactory results, which can classify correctly 91.5% of the compounds in the training set and 91.4% of the compounds in the testing set. In addition, this paper provides a new and effective method for classifying the new anti‐HIV nucleoside derivatives from their structures according to their activities and gives some insight into structural features related to the activity of the drugs.
Quantitative Structure–Activity Relationships for Enzymatic Activity of Chloroperoxidase on Metabolizing Organophosphorus Pesticides
Authors: Lu Gui‐Ning , Dang Zhi , Tao Xue‐Qin , Chen Xiao‐Peng , Yi Xiao‐Yun , Yang Chen
Published: August 2006

Quantitative Structure–Activity Relationship (QSAR) is a powerful approach for predicting activities of organic pollutants with their structure descriptors. This study reports QSAR models for predicting enzymatic activity of chloroperoxidase on metabolizing selected Organophosphorus Pesticides (OPPs). We used ten quantum chemical descriptors computed with ab initio method at HF/6‐31G(d) level and Partial Least Squares (PLS) analysis with optimizing procedure for generating QSAR models. The correlation coefficient of the optimal model was 0.918, and the fitting results showed that it had high fitting precision and good predicting ability. The PLS assistant analysis indicated that the atomic charges of sulfur and phosphorus atoms in the SP bond of an OPP molecule were important in governing the enzymatic activity and the molecular dipole moment also had some effect on the enzymatic activity. It was found that OPPs with high absolute values of atomic charges on the sulfur and phosphorus atoms tended to be metabolized faster, whereas OPPs with stronger polarity tended to be metabolized slower by chloroperoxidase. The optimal model was used to predict the enzymatic activity of two OPPs and the results appeared to be reasonable.
Development and validation of a liquid chromatography/tandem mass spectrometry method for the determination of the novel anticancer agent 17‐DMAG in human plasma
Authors: Moreno‐Farre Javier , Asad Yasmin , Pacey Simon , Workman Paul , Raynaud Florence I.
Published: August 2006

An accurate, sensitive, robust and selective liquid chromatography/tandem mass spectrometry (LC/MS/MS) method for the determination of 17‐(dimethylaminoethylamino)‐17‐demethoxygeldanamycin hydrochloride (17‐DMAG) in human plasma has been developed and validated. Plasma samples were prepared by liquid/liquid extraction with ethyl acetate. The chromatographic separation was achieved within 9 min on a Synergy Polar column with a linear gradient and a mobile phase consisting of methanol and 0.1% formic acid in water. Detection of 17‐DMAG and the internal standard (IS), olomoucine, was achieved by MS/MS with electrospray ionisation in positive ion mode. The calibration curve, ranging from 1.89 to 1890 nM, was linear r > 0.994 using a 1/y2 weighted linear regression. The assay showed no significant interferences from endogenous compounds. The lower limit of quantitation (LLOQ) was 1.89 nM, using 250 µL of plasma, with inter‐assay precision (%RSD) and accuracy (%RE) values of 11.6% and −5.8%, respectively. Intra‐assay precision ranged from 7.8–13.6%. The method described here is being used to evaluate the pharmacokinetic profiles of 17‐DMAG given as a once weekly infusion in patients with advanced solid tumours. Copyright © 2006 John Wiley & Sons, Ltd.
Conic S‐procedure and constrained dissipativity for linear systems
Authors: L. Fradkov A.
Published: August 2006

A new proof and extension of the recent result of Iwasaki et al. (Systems Control Lett. 2005; 54(7):681–691) concerning equivalence of frequency domain inequality on finite frequency range and constrained dissipativity property for linear systems is given. The results of this paper employ an extended version of S‐procedure based on duality in the space of positive definite matrices and introduction of matrix Lagrange multipliers, proposed by Yakubovich in 1992. Copyright © 2006 John Wiley & Sons, Ltd.
Optimal designs for radiation retention with Poisson correlated response
Authors: López‐Fidalgo J. , Villarroel J.
Published: August 2006

In this paper we describe a non‐linear model with correlated observations which accounts for the elimination rate of radiation in the lung of individuals who have been exposed to an accidental intake at some time. The response is then modelled as a conditional Poisson distribution. When the leak is moderate or the size of the particles is large a theoretical justification of this assumption is given and D‐optimal designs are computed. Copyright © 2006 John Wiley & Sons, Ltd.
Cover Picture: Complementary Symmetry Silicon Nanowire Logic: Power‐Efficient Inverters with Gain (Small 10/2006)
Authors: Wang Dunwei , Sheriff Bonnie A. , Heath James R.
Published: August 2006

The cover picture illustrates a complementary symmetry‐based inverter logic gate fabricated from dense arrays of silicon nanowires. Such logic circuits are highly energy efficient and exhibit gain, but require both p‐type and n‐type transistors (represented as the dark green and orange wires in the central drawing). The upper‐left electron micrograph shows an array of the 15‐nm‐wide silicon nanowires that were utilized to make the inverters. The upper‐right trace represents the output of the inverter: as the input (x axis) voltage is increased, the output voltage (y axis) switches from high to low. The background and bottom‐right micrographs are images of the actual circuits. For more information, please read the Communication “Complementary Symmetry Silicon Nanowire Logic: Power‐Efficient Inverters with Gain” by J. R. Heath and co‐workers on page 1153 ff.
Forward focus: using routing information to improve medium access control in ad hoc networks
Authors: Ishibashi Brent , Boutaba Raouf
Published: August 2006

Multihop packet forwarding is a vital process in an ad hoc network. All ad hoc networking protocols, but particularly routing and medium access control protocols, must work together in order for the network to be successful. However, current MAC protocols such as IEEE 802.11 do not consider this multihop nature at all. This work develops a modification to 802.11 that focuses on forwarding packets. Routing information is utilized to streamline the sharing of the medium, by allowing forwarding nodes to reuse an already‐acquired channel. Using forward focus (FF), nodes are encouraged to participate in the forwarding process and are rewarded for doing so. Simulation‐generated performance evaluations reveal that the result is a MAC protocol with improved efficiency and effectiveness. Copyright © 2006 John Wiley & Sons, Ltd.
Why American business demands twenty‐first century learning: A company perspective
Authors: Knox Allyson
Published: August 2006

Microsoft, one of the world's largest corporations, evaluates its employees' performance against twenty‐first century skills and works to improve education in the digital age.