bluuebunny/crossref_metadata_2025 huggingface dataset:
Preparation, characterization, and application of thin film composite nanofiltration membranes
Authors: Song Yujun , Liu Fuan , Sun Benhui
Published: January 2005

The active aromatic polyamide layers of thin film composite nanofiltration (NF‐TFC) membranes were prepared via interfacial polymerization (IP) from three different types of polyamine: p‐phenylenediamine (PPD), m‐phenylenediamine (MPD), or piperazine (PRP), and trimesoyl chloride (TMC) on polysulfone/sulfonated polysulfone (PSf/SPSf) alloy substrates. Chemical components, cross section structures, and thermal properties of the polyamide active layers and the bulk membranes, characterized by Fourier transfer IR spectroscopy and attenuated total reflection IR spectroscopy, scanning electron microscopy, and differential scanning calorimetry and thermogravimetry, respectively, revealed an interpenetrating layer between the polyamide active layer and the substrate. A ridge–valley structural active layer was formed on the PSf/SPSf substrate for the NF‐TFC membrane with a thick polyacrylamide (PA) layer. Compared with the NF‐TFC membranes on PSf substrates, those on PSf/SPSf alloy substrates had a higher permeability without losing the selectivity by introducing the hydrophilic SPSf into the hydrophobic PSf substrates. The binding between the modified substrate and the active PA layer was also improved. Good separation performances using these NF‐TFC membranes were obtained in the polyvalent ion separation, the ground water softening, and the treatment of wastewater from adipic acid plants in a wide pH range. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 95: 1251–1261, 2005
Identification of caprolactam oligomers and related compounds in aqueous extracts of nylon‐6
Authors: Jenke Dennis , Poss Mitchell , Sadain Salma , Story James , Smith Walter , Reiber Duane
Published: January 2005

Cyclic oligomers of caprolactam were isolated from a multilayered polyolefin plastic film containing a nylon‐6 layer and subsequently characterized. Nylon‐6 was extracted with aqueous solutions and the levels of the oligomers were measured in the resulting extracts. Oligomers up to n = 5 were present at high and comparable levels in all the nylon‐6 extracts. The levels of the oligomers dropped off rapidly with increased compound size after n = 5, with the heptamer being barely observable in the extract chromatograms. The effect of extracting solution pH on the compound's concentration in the extract was small, except for the monomer, whose accumulation was significantly decreased at low pH. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 95: 1262–1274, 2005
Genescene: An ontology‐enhanced integration of linguistic and co‐occurrence based relations in biomedical texts
Authors: Leroy Gondy , Chen Hsinchun
Published: January 2005

The increasing amount of publicly available literature and experimental data in biomedicine makes it hard for biomedical researchers to stay up‐to‐date. Genescene is a toolkit that will help alleviate this problem by providing an overview of published literature content. We combined a linguistic parser with Concept Space, a co‐occurrence based semantic net. Both techniques extract complementary biomedical relations between noun phrases from MEDLINE abstracts. The parser extracts precise and semantically rich relations from individual abstracts. Concept Space extracts relations that hold true for the collection of abstracts. The Gene Ontology, the Human Genome Nomenclature, and the Unified Medical Language System, are also integrated in Genescene. Currently, they are used to facilitate the integration of the two relation types, and to select the more interesting and high‐quality relations for presentation. A user study focusing on p53 literature is discussed. All MEDLINE abstracts discussing p53 were processed in Genescene. Two researchers evaluated the terms and relations from several abstracts of interest to them. The results show that the terms were precise (precision 93%) and relevant, as were the parser relations (precision 95%). The Concept Space relations were more precise when selected with ontological knowledge (precision 78%) than without (60%).
Developing a protocol for bioinformatics analysis: An integrated information behavior and task analysis approach
Authors: Bartlett Joan C. , Toms Elaine G.
Published: January 2005

The purpose of this research is to capture, understand, and model the process used by bioinformatics analysts when facing a specific scientific problem. Integrating information behavior with task analysis, we interviewed 20 bioinformatics experts about the process they follow to conduct a typical bioinformatics analysis—a functional analysis of a gene, and then used a task analysis approach to model that process. We found that each expert followed a unique process in using bioinformatics resources, but had significant similarities with their peers. We synthesized these unique processes into a standard research protocol, from which we developed a procedural model that describes the process of conducting a functional analysis of a gene. The model protocol consists of a series of 16 individual steps, each of which specifies detail for the type of analysis, how and why it is conducted, the tools used, the data input and output, and the interpretation of the results. The linking of information behavior and task analysis research is a novel approach, as it provides a rich high‐level view of information behavior while providing a detailed analysis at the task level. In this article we concentrate on the latter.
Mechanisms regulating toxicant disposition to the embryo during early pregnancy: An interspecies comparison
Authors: Carney Edward W. , Scialli Anthony R. , Watson Rebecca E. , DeSesso John M.
Published: January 2005

The dose of toxicant reaching the embryo is a critical determinant of developmental toxicity, and is likely to be a key factor responsible for interspecies variability in response to many test agents. This review compares the mechanisms regulating disposition of toxicants from the maternal circulation to the embryo during organogenesis in humans and the two species used predominantly in regulatory developmental toxicity testing, rats and rabbits. These three species utilize fundamentally different strategies for maternal‐embryonic exchange during early pregnancy. Early postimplantation rat embryos rely on the inverted visceral yolk sac placenta, which is in intimate contact with the uterine epithelium and is equipped with an extensive repertoire of transport mechanisms, such as pinocytosis, endocytosis, and specific transporter proteins. Also, the rat yolk sac completely surrounds the embryo, such that the fluid‐filled exocoelom survives through most of the period of organogenesis, and can concentrate compounds such as certain weak acids due to pH differences between maternal blood and exocelomic fluid. The early postimplantation rabbit conceptus differs from the rat in that the yolk sac is not closely apposed to the uterus during early organogenesis and does not completely enclose the embryo until relatively later in development (∼GD13). This suggests that the early rabbit yolk sac might be a relatively inefficient transporter, a conclusion supported by limited data with ethylene glycol and one of its predominant metabolites, glycolic acid, given to GD9 rabbits. In humans, maternal‐embryo exchange is thought to occur via the chorioallantoic placenta, although it has recently been conjectured that a supplemental route of transfer could occur via absorption into the yolk sac. Knowledge of the mechanisms underlying species‐specific embryonic disposition, factored together with other pharmacokinetic characteristics of the test compound and knowledge of critical periods of susceptibility, can be used on a case‐by‐case basis to make more accurate extrapolations of test animal data to the human. Birth Defects Research (Part C) 72:345–360, 2005. © 2005 Wiley‐Liss, Inc.
The feasibility of adjuvant interferon α‐2b in children with high‐risk melanoma
Authors: Navid Fariba , Furman Wayne L. , Fleming Martin , Rao Bhaskar N. , Kovach Sandra , Billups Catherine A. , Cain Alvida M. , Amonette Rex , Jenkins Jesse J. , Pappo Alberto S.
Published: January 2005

BACKGROUND

It has been shown that induction high‐dose interferon α‐2b (IFN‐α‐2b) followed by maintenance therapy improves recurrence‐free survival in adults with high‐risk, resected melanoma. In this study, the feasibility and toxicity of this regimen were evaluated in newly diagnosed pediatric patients with Stage III melanoma involving regional lymph nodes.

METHODS

Fifteen patients age ≤ 18 years with newly diagnosed Stage III melanoma were enrolled on an institutional protocol. Patients were treated with wide local excision, sentinel lymph node biopsy, lymph node dissection, and adjuvant biotherapy, consisting of induction therapy with 20 million IU/m2 per day IFN‐α‐2b intravenously 5 times per week for 4 weeks followed by maintenance therapy with IFN‐α‐2b 10 million IU/m2 per day subcutaneously 3 times per week for 48 weeks. Patients were monitored for toxicity and tumor recurrence.

RESULTS

All patients completed induction therapy, and nine patients completed maintenance therapy. Three patients currently are receiving maintenance, 2 patients developed recurrent disease on maintenance therapy, and 1 patient stopped maintenance therapy 5 weeks early. During induction therapy, Grade 3–4 toxicities included 14 episodes of neutropenia in 11 patients, 3 episodes of leukopenia in 2 patients, and 6 episodes of liver transaminase elevations in 5 patients. Dose modifications were required in four patients. During maintenance therapy, Grade 3–4 toxicities included 23 episodes of neutropenia in 10 patients and 2 episodes of liver transaminase elevations in 2 patients. Three patients required dose modifications. All toxicities were reversible with interruption or dose modification of therapy, and no patients were taken off study due to toxicity.

CONCLUSIONS

High dose IFN‐α‐2b for 4 weeks followed by a lower dose maintenance phase for 48 weeks was feasible in children with Stage III melanoma and was associated with tolerable toxicity. Cancer 2005. © 2005 American Cancer Society.
Current‐mode programmable piecewise‐linear neural synapses
Authors: Balsi Marco , Giuliani Giancarlo
Published: January 2005

Cellular Neural Networks with piecewise linear connection have been proposed by several authors as a generalization of the basic paradigm, which allows for more complex functionality. None of the prototypes realized to date, however, provides for such kind of synapses. As a feasibility study, a current‐mode subthreshold CMOS piecewise‐linear synapse circuit is developed in this paper. Copyright © 2003 John Wiley & Sons, Ltd.
Autonomous driving control for ITS by using learning automaton network with multiple environments
Authors: Shiraishi Kazuaki , Hamagami Tomoki , Koakutsu Seiichi , Hirata Hironori
Published: January 2005

In this paper, the application of the learning automaton (LA) network with multiple environments is proposed for the adaptive controller for ITS autonomous driving. The LA network, which we introduced previously, has the ability to learn which deals with both multiple reinforcement signals and information of multiple environments at the same time. This feature is found to be useful for improving the response of adaptation in dynamic environments such as highways. In order to evaluate the practical advantage of using the network, we designed a simulational highway system, constructed an autonomous travel controller using the simple LA and the LA network, and executed comparative experiments evaluating the performance of adaptation response and collision avoidance. The results show that the performance of the LA network with multiple environments is superior to that using simple LA application with regard to stability and safety. © 2005 Wiley Periodicals, Inc. Electr Eng Jpn, 150(4): 36–43, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.10363
A pulsed power supply with sag compensation using controlled gradational voltage
Authors: Suzuki Akihiro , Yamada Masaki , Tashiro Shojirou , Iwata Akihiko
Published: January 2005

A pulsed power supply with sag compensation using controlled gradational voltage to increase the flatness of output waveforms has been developed. The sag compensation circuit consists of compensation units connected in series. Each compensation unit consists of capacitances, diodes, and semiconductor switches. The capacitances of each unit are charged with different voltages by 2n(V0,2V0,4V0,…). The compensation voltage, which has 2n−1 steps, is generated by switching the semiconductor switches of each unit in a binary sequence. Using this method, compensation voltage waveforms up to 6.2 kV with 31 steps can be obtained with five compensation units. The sag compensation circuit has been adapted to a direct switch‐type pulsed power supply, which generates 7 kV pulsed voltage with a pulse width of 700µs, thus realizing sag compensation. © 2005 Wiley Periodicals, Inc. Electr Eng Jpn, 150(4): 54–63, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20017
Perspective on concentration polarization effects in electrochromatographic separations
Authors: Tallarek Ulrich , Leinweber Felix C. , Nischang Ivo
Published: January 2005

This work illustrates the appearance and electrohydrodynamic consequences of concentration polarization in the particulate and monolithic fixed beds used in capillary electrochromatography and related electrical‐field assisted processes. Key property of most porous materials is the co‐existence of bulk, quasi‐electroneutral macroporous regions and mesoporous compartments which are ion‐permselective (due to electrical double‐layer overlap) causing different transport numbers for co‐ionic and counterionic species, e.g., background electrolyte components, or the analytes. For a cathodic electroosmotic flow the (cation) permselectivity, together with diffusive and electrokinetic transport induces depleted and enriched concentration polarization zones at the anodic and cathodic interfaces, respectively, in dependence of the mobile phase ionic strength and applied electrical fields. At high field strength a secondary, nonequilibrium electrical double layer may be created in the depleted concentration polarization zones of a material stimulating electroosmosis of the second kind. The potential of this induced‐charge electroosmosis with respect to nonlinear flow velocities and electrokinetic instability mixing (basically destroying the concentration polarization zones) is analyzed in view of the pore space morphology in random‐close packings of spherical‐shaped, porous particles and hierarchically structured monoliths. Possible applications based on a fine‐tuning of the illustrated effects emerge for microfluidic pumping and mixing, or the intensification of sample recovery in adsorption processes. With this perspective we want to focus the attention on concentration polarization in electrochromatographic systems by presenting and discussing original data acquired on relevant microscopic as well as macroscopic scales, and point towards the importance of related effects in colloid and membrane science.*
Conductivity properties of carrier ampholyte pH gradients in isoelectric focusing
Authors: Stoyanov Alexander V. , Das Champak , Fredrickson Carl K. , Fan Z. Hugh
Published: January 2005

The conductivity properties of natural pH gradient created by carrier ampholytes were studied during the process of isoelectric focusing (IEF). IEF was performed in capillaries (10–30 mm long) or in microchips with the same channel length. A 10–30× reduction of the conductivity of the separation medium was observed during the establishment of pH gradient. Results obtained using different IEF voltages indicate that there is a nonlinear relationship between the conductivity of an established pH gradient and the applied electric field. Our theoretical analysis using a simplified model generated values that reasonably agree with the experimental data. In addition, we found that above a certain electric field (∼300 V/cm), resolution does not increase with the applied voltage as predicated; we observed band‐broadening and gel breakdown. The approach presented in this work can be used for optimization of the IEF separation and judicious selection of IEF conditions.
Motion of single long DNA molecules through arrays of magnetic columns
Authors: Minc Nicolas , Bokov Plamen , Zeldovich Konstantin B. , Fütterer Claus , Viovy Jean‐Louis , Dorfman Kevin D.
Published: January 2005

We present a videomicroscopy study of T4 DNA (169 kbp) in microfluidic arrays of posts formed by the self‐assembly of magnetic beads. We observe DNA moving through an area of 10 000 µm2, typically containing 100–600 posts. We determine the distribution of the contact times with the posts and the distribution of passage times across the field of view for hundreds of DNA per experiment. The contact time is well approximated by a Poisson process, scaling like the inverse of the field strength, independent of the density of the array. The distribution of passage times allows us to estimate the mean velocity and dispersivity of the DNA during its motion over distances long compared to our field of view. We compare these values with those computed from a lattice Monte Carlo model and geometration theory. We find reasonable quantitative agreement between the lattice Monte Carlo model and experiment, with the error increasing with increasing post density. The deviation between theory and experiment is attributed to the high mobility of DNA after disengaging from the posts, which leads to a difference between the contact time and the total time lost by colliding. Classical geometration theory furnishes surprisingly good agreement for the dispersivity, while geometration theory with a mean free path significantly overestimates the dispersivity.
Editorial: Electrophoresis 2/2005
Authors: Gaš Bohuslav , Boček Petr
Published: January 2005

No abstracts.
Antidepressant drug prescribing among elderly subjects: a population‐based study
Authors: Percudani Mauro , Barbui Corrado , Fortino Ida , Petrovich Lorenzo
Published: January 2005

Background

The patterns of antidepressant drug prescribing have rarely been studied in large and geographically defined populations of elderly subjects. In the present study we examined the prevalence and distribution of antidepressant prescribing in Lombardy, a northern Italy region with more than one and a half million elderly inhabitants.

Methods

We used the Regional Administrative Database of Lombardy. This database includes all prescriptions reimbursed by the National Health System in the population living in this region. All antidepressant prescriptions dispensed to subjects aged 65 years or above during 2001 were extracted and prevalence data calculated by dividing antidepressant users by the total number of male and female residents in each age group.

Results

During the 12 months surveyed 153,706 subjects were dispensed one or more prescriptions of antidepressants, yielding a prevalence of use of 9.49 subjects per 100 inhabitants (95% confidence interval 9.44, 9.53). Although the proportion of chronic users slightly decreased with age, more than 35% of those older that 85 years were moderate or chronic antidepressant users. General practitioners issued the majority of antidepressant prescriptions, and most antidepressant users were also dispensed agents for medical disorders.

Conclusions

The very high rates of antidepressant drug prescribing detected in late life suggest the need of characterising these subjects in terms of medical and psychiatric characteristics, needs and quality of life. It also suggests the need for pragmatic clinical trials, carried out in the general practice, with the aim of assessing whether antidepressants are effective in these conditions. Copyright © 2005 John Wiley & Sons, Ltd.
Object naming and semantic fluency among individuals with genetic risk for Alzheimer's disease
Authors: Miller Karen J. , Rogers Steven A. , Siddarth Prabha , Small Gary W.
Published: January 2005

Objectives

This study longitudinally examined the object naming and semantic fluency of individuals who are at risk for developing Alzheimer's disease (AD) by virtue of having APOE‐4 or a family history of AD.

Methods

A total of 108 participants (40 with a family history of AD and 43 with APOE‐4) completed the Boston Naming Test and the Animal Naming task at initial assessment and after two years.

Results

At baseline, object naming was significantly lower for those with both risk factors, F(2, 99) = 5.72, p < 0.01, but those with either risk factor had significantly lower scores at follow‐up, F(2, 99) = 3.41, p < 0.05. Semantic fluency (animal naming) was reduced among subjects with the APOE‐4 allele at baseline, F(1, 100) = 4.02, p < 0.05, but it was not associated with either risk factor at follow‐up.

Conclusions

These deficits may be associated with a prodromal risk for AD and may serve as pre‐symptomatic markers for the development of AD. Copyright © 2005 John Wiley & Sons, Ltd.
Stimulation of neurite outgrowth in a human nerve scaffold designed for peripheral nerve reconstruction
Authors: Dumont Charles E. , Born Walter
Published: January 2005

The clinical outcome of microsurgical reconstruction of large peripheral nerve lesions depends on the availability of suitable graft material. Allogenic nerve grafts are rejected by the immune system. Extracellular‐matrix proteins, in contrast to the resident cells, are of low immunogenicity in allografts. Here, human tibial nerve segments were extracted with lysophosphatidyl choline. The obtained cell‐free and myelin‐free scaffold consisted of empty endoneural tubes with maintained extracellular matrix architecture. The nerve scaffold had mechanical properties comparable to intact nerve, making it suitable for microsurgical reconstruction. Sections of the nerve scaffold were tested as a substrate for the adhesion and neuronal differentiation of human neuroblastoma‐derived LAN‐5 cells. Nerve extraction removed laminin‐2, an isoform of laminin important for peripheral nerve regeneration. Laminin‐2 reloading of the nerve scaffold did not improve cell adhesion and axon growth. Chemical crosslinking of heparan sulfate, on the other hand, increased the percentage of adherent cells with outgrowing neurites from 48 to 85%. Combined laminin‐2 reloading and heparan sulfate crosslinking reduced the percentage of neurite‐forming cells to 22% of the number of adherent cells. Implantation of the nerve scaffold into the peritoneal cavity of mice was not cytotoxic, and neovascularization of the graft material was observed within weeks. In conclusion, extraction of human nerve with detergents revealed a biocompatible nerve scaffold supporting neuronal cell adhesion. Heparan sulfate crosslinking to the scaffold surface improved neurite outgrowth, presumably mediated by midkine, a member of the neurokine family of growth factors, which is secreted by neuroblastoma‐derived cells and binds to heparan sulfate. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 73B: 194–202, 2005
A comparative study of thein vitrocorrosion behavior and cytotoxicity of a superferritic stainless steel, a Ti‐13Nb‐13Zr alloy, and an austenitic stainless steel in Hank's solution
Authors: Assis S. L. , Rogero S. O. , Antunes R. A. , Padilha A. F. , Costa I.
Published: January 2005

In this study, thein vitrocorrosion resistance of a superferritic stainless steel in naturally aerated Hank's solution at 37°C has been determined to evaluate the steel for use as a biomaterial. The potentiodynamic polarization method and electrochemical impedance spectroscopy (EIS) were used to determine the corrosion resistance. The polarization results showed very low current densities at the corrosion potential and electrochemical behavior typical of passive metals. At potentials above 0.75 V (SCE), and up to that of the oxygen evolution reaction, the superferritic steel exhibited transpassive behavior followed by secondary passivation. The superferritic stainless steel exhibited high pitting resistance in Hank's solution. This steel did not reveal pits even after polarization to 3000 mV (SCE). The EIS results indicated high impedance values at low frequencies, supporting the results obtained from the polarization measurements. The results obtained for the superferritic steel have been compared with those of the Ti‐13Nb‐13Zr alloy and an austenitic stainless steel, as Ti alloys are well known for their high corrosion resistance and biocompatibility, and the austenitic stainless steel is widely used as an implant material. The cytotoxicity tests indicated that the superferritic steel, the austenitic steel, and the Ti‐13Nb‐13Zr alloy were not toxic. Based on corrosion resistance and cytotoxicity results, the superferritic stainless steel can be considered as a potential biomaterial. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 73B: 109–116, 2005
Amorphous Ni–B/SiO2catalyst prepared by microwave heating and its catalytic activityin acrylonitrile hydrogenation
Authors: Liu Bo , Qiao Minghua , Wang Jianqiang , Xie Songhai , Li Hexing , Fan Kangnian
Published: January 2005

Microwave heating was utilized in the preparation of amorphous Ni–B/SiO2catalysts. After wetness impregnation with NiCl2aqueous solution, the catalyst precursor was dried at 383 K, followed by microwave heating and KBH4reduction. Liquid phase hydrogenation of acrylonitrile was employed as the probe reaction. While ICP, XRD, XPS and turnover frequency results did not reveal discernable structural and electronic differences between the active components of the catalysts with or without microwave heating, SEM uncovered the formation of smaller Ni–B alloy particles with microwave heating, leading to a higher concentration of active sites and greater thermal stability as verified by H2chemisorption and DSC. Copyright © 2003 Society of Chemical Industry
Termination Kinetics of Dibutyl Itaconate Free‐Radical Polymerization Studied via the SP–PLP–ESR Technique
Authors: Buback Michael , Egorov Mark , Junkers Tanja , Panchenko Elena
Published: January 2005

Summary: The termination kinetics of dibutyl itaconate (DBI) bulk polymerization was studied via SP–PLP–ESR single pulse–pulsed laser polymerization with time‐resolved detection of free‐radical concentration by electron‐spin resonance, at temperatures between 0 and 60 °C. As is characteristic of PLP experiments, termination rate coefficients, kt(i,i), are measured for radicals of (almost) identical chain length (CL) i. CL‐averaged 〈kt〉, for chain lengths up to 200 monomer units, and also k referring to termination of very small‐size radicals are directly deduced from measured DBI radical concentration vs time traces. At 45 °C, 〈kt〉 is (3.4 ± 0.6) · 105 L · mol−1 · s−1 and k is (7.2 ± 1.0) · 105 L · mol−1 · s−1. Both rate coefficients are independent of monomer conversion up to the highest experimental conversion of 18%. The associated activation energies are EA(〈kt〉) = 23.0 ± 3.2 kJ · mol−1 and EA(k) = 27.6 ± 2.8 kJ · mol−1, respectively. “Model‐dependent” and “model‐free” analyses of radical concentration vs time profiles indicate a pronounced CL dependence of kt(i,i) for DBI radicals of moderate size, 5 < i < 50. The lowering of kt(i,i) with CL corresponds to an exponent α close to 0.5 in a power‐law expression kt(i,i) = k · i−a. At higher chain lengths, the variation of kt(i,i) with CL becomes weaker and may be represented by an α value of 0.16 or even below. These results are consistent with models according to which α varies to a larger extent at low CL and to a smaller extent at high CL with the crossover region between the two ranges being located somewhere around i = 100.

Conversion‐dependence of 〈kt〉 and k from laser‐induced photopolymerization of DBI.

magnified image

Conversion‐dependence of 〈kt〉 and k from laser‐induced photopolymerization of DBI.
A Novel Approach to the Preparation of Nanoblends of Poly(2,6‐dimethyl‐1,4‐phenylene oxide)/Polyamide 6
Authors: Ji Yali , Li Wengang , Ma Jinghong , Liang Borun
Published: January 2005

Summary: A novel approach of in situ polymerization and in situ compatibilization was adopted to prepare poly(2,6‐dimethyl‐1,4‐phenylene oxide) (PPO) and polyamide 6 (PA6) nanoblends. Anionic ring‐opening polymerization of ε‐caprolactam was carried out in the presence of PPO, the chain of which bore p‐methoxyphenylpropionate (MPAA), acting as macroactivator to initiate PA6 chain growth from the PPO chain and form a graft copolymer of PPO and PA6 and pure PA6 simultaneously. The nanostructured PA6 dispersed phase in the PPO matrix could be achieved.

A TEM image of poly(2,6‐dimethyl‐1,4‐phenylene oxide)/polyamide 6 nanoparticles obtained from in situ polymerization and in situ compatibilization.

image

A TEM image of poly(2,6‐dimethyl‐1,4‐phenylene oxide)/polyamide 6 nanoparticles obtained from in situ polymerization and in situ compatibilization.
Nemaline rods in chorea‐acanthocytosis
Authors: Tamura Yohei , Matsui Kazutaka , Yaguchi Hiroshi , Hashimoto Masaya , Inoue Kiyoharu
Published: January 2005

In chorea‐acanthocytosis, a neurological disorder associated with multisystem degeneration, amyotrophy and peripheral neuropathy are sometimes conspicuous. We describe a patient with chorea‐acanthocytosis who showed distributed nemaline rods in biopsied muscle. It has been suggested that in chorea‐acanthocytosis, the muscle membranous structures are disordered, and our finding may be attributable to this underlying myopathic condition. Muscle Nerve, 2005
Barrett's adenocarcinomas resemble adenocarcinomas of the gastric cardia in terms of chromosomal copy number changes, but relate to squamous cell carcinomas of the distal oesophagus with respect to the presence of high‐level amplifications
Authors: Weiss Marjan M , Kuipers Ernst J , Hermsen Mario AJA , van Grieken Nicole CT , Offerhaus Johan , Baak Jan PA , Meuwissen Stefan GM , Meijer Gerrit A
Published: January 2005

Three different cancers predominantly occur at the gastro‐oesophageal junction: squamous cell carcinomas of the distal oesophagus, adenocarcinomas of the distal oesophagus (Barrett's carcinomas), and adenocarcinomas of the gastric cardia. The aim of the present study was to investigate how, and to what extent, Barrett's carcinoma differs from adenocarcinoma of the gastric cardia on the one hand and squamous cell carcinoma of the distal oesophagus on the other, with respect to chromosomal aberrations and related gene expression. The present study analysed 14 squamous cell carcinomas, 24 Barrett's carcinomas, and 16 carcinomas of the gastric cardia. Comparative genomic hybridization revealed chromosomal abnormalities in all cases. Typical chromosomal aberrations for the squamous cell carcinoma type were gains at 3q and 11q13, and losses at 3p, 4q, 9p, 11q, and 13q. In contrast, typical copy number changes for both cardiac and Barrett's adenocarcinomas were gains at 2q, 7p, and 13q, and losses at 17p. High‐level amplification occurred in all three groups, but its frequency in the cardiac carcinomas was lower than in the other two groups. In conclusion, squamous cell carcinomas are characterized by chromosomal aberrations which are distinct from those seen in carcinomas of the gastric cardia and in Barrett's adenocarcinomas. With respect to Barrett's cancer, the chromosomal aberrations more closely reflect the adenocarcinoma phenotype than the squamous origin of the epithelium. Copyright © 2002 John Wiley & Sons, Ltd.
Mutations of mtDNA in renal cell tumours arising in end‐stage renal disease
Authors: Nagy Anetta , Wilhelm Monica , Kovacs Gyula
Published: January 2005

Toxic effects in the uraemic state or during maintenance dialysis have been suggested to be responsible for DNA damage and tumour development in end‐stage renal disease (ESRD). This study therefore analysed the mitochondrial DNA alterations in six kidneys with ESRD and in nine renal cell tumours arising in these kidneys. Sequencing the entire 16 569 bp mitochondrial genome disclosed 94 sequence variations in normal and corresponding tumour tissues. Thirty‐eight polymorphisms occurred in the D‐loop region, 40 in the polypeptide coding regions, 12 in the rRNAs, and four in the tRNAs. Nine somatic nucleotide changes were found in seven of the nine tumours analysed; four of them were G to A transitions. Two of the G to A changes occurred in the D‐loop region, one in the MTTA gene, and one in the MTND2 gene. An A to G substitution was seen in the control region at the mtTF1 binding site. A T to C transition also occurred also in the D‐loop region. A T insertion was seen in MTRNR2 (16S rRNA). One C insertion in MTND4 and one A deletion in the polyA tract of the MTND5 gene resulted in frameshift mutations in two tumours. This study reveals a high mutational rate of the mitochondrial DNA in tumours, which may correspond to the increased level of reactive oxidative species in renal parenchymal cells in ESRD. Copyright © 2003 John Wiley & Sons, Ltd.
Association of trypsin expression with tumour progression and matrilysin expression in human colorectal cancer
Authors: Yamamoto Hiroyuki , Iku Shouhei , Adachi Yasushi , Imsumran Arisa , Taniguchi Hiroaki , Nosho Katsuhiko , Min Yongfen , Horiuchi Shina , Yoshida Mio , Itoh Fumio , Imai Kohzoh
Published: January 2005

Overexpression of the matrix serine protease (MSP) trypsin has been implicated in tumour growth, invasion, and metastasis. The objective of this study was to clarify the clinicopathological and prognostic significance of trypsin expression in colorectal cancer. This study analysed the association between immunohistochemically detected trypsin expression in colorectal cancer and clinicopathological characteristics, and investigated whether trypsin is a predictor of recurrence and/or survival. Trypsin immunoreactivity was more intense at the invasive front than in the superficial part of the tumour. Sections with immunostaining signals in more than 30% of carcinoma cells at the invasive front, which were observed in 48 cases (48%), were judged to be positive for trypsin. Trypsin positivity was significantly correlated with depth of invasion, lymphatic and venous invasion, lymph node and distant metastasis, advanced pathological tumour–node–metastasis (TNM) stage, and recurrence. Patients with trypsin‐positive carcinoma had significantly shorter overall and disease‐free survival periods than did those with trypsin‐negative carcinoma. Trypsin retained its significant predictive value for overall and disease‐free survival in multivariate analysis that included conventional clinicopathological factors. It is well known that trypsin activates matrilysin (matrix metalloproteinase‐7), which plays an important role in colorectal cancer progression. Patients with concordant overexpression of trypsin and matrilysin at the invasive front, in which they were often co‐localized, had the worst prognosis. Trypsinogen‐1‐transfected HCT116 colon cancer cells showed not only trypsin activity, but also active matrilysin activity and were more invasive in vitro than mock‐transfected HCT116 cells. These results suggest that trypsin plays a key role in the progression of colorectal cancer. Detection of trypsin expression as well as matrilysin is useful for the prediction of recurrence in and poor prognosis of colorectal cancer patients. Copyright © 2003 John Wiley & Sons, Ltd.
Comparison of immunohistochemistry for activated caspase‐3 and cleaved cytokeratin 18 with the TUNEL method for quantification of apoptosis in histological sections of PC‐3 subcutaneous xenografts
Authors: Duan W Rachel , Garner Debra S , Williams Steven D , Funckes‐Shippy Christie L , Spath Iwona S , Blomme Eric AG
Published: January 2005

The terminal deoxynucleotidyl transferase (TdT)‐mediated dUTP nick‐end labelling (TUNEL) technique has been extensively used for the detection and quantification of apoptosis in histological tissue sections. However, the interpretation and specificity of this assay have been controversial. With accumulating knowledge of the molecular mechanisms of cell death and the discovery of the caspases as key mediators of apoptosis, more direct and earlier measurements of apoptosis in tissue sections have emerged. This study, using antibodies that specifically recognize activated caspase‐3 and caspase‐cleaved cytokeratin (CK) 18, evaluated whether immunohistochemical stains would improve the detection and quantification of apoptosis in tissue sections, compared with the TUNEL assay. Tumour xenografts of the prostate cancer cell line PC‐3 were used as an example, since these tissues contain large numbers of cells undergoing apoptosis. Apoptotic cells were quantified and apoptotic indices were calculated by computer‐assisted image analysis following identification of apoptotic cells by morphological analysis, the TUNEL assay, activated caspase‐3 and cleaved CK18 immunohistochemistry. The results indicated that activated caspase‐3 immunohistochemistry was an easy, sensitive, and reliable method for detecting and quantifying apoptosis in this model. An excellent correlation (R = 0.89) between the apoptotic indices obtained using activated caspase‐3 and cleaved CK18 immunostaining was observed. A good correlation (R = 0.75) between the apoptotic indices obtained using activated caspase‐3 immunostaining and the TUNEL assay was also found. Activated caspase‐3 immunohistochemistry is therefore recommended for the detection and quantification of apoptosis in tissue sections. Copyright © 2003 John Wiley & Sons, Ltd.
Preparation and properties of novel polyurethane insulating coatings based on glycerin‐terminated urethane prepolymers and blocked isocyanate
Authors: Yeganeh Hamid , Shamekhi Mohammad Amin
Published: January 2005

Novel polyurethane insulating coatings were prepared from the reaction of glycerin‐terminated polyurethane prepolymers (GPUPs) and a blocked isocyanate curing agent (BIC). The GPUPs were prepared from the reaction of one equivalent of polycaprolactone polyol (CAPA 210) with an excess amount of 4,4′‐methylene bis(phenyl isocyanate) (MDI) and subsequent reaction of the NCO‐terminated polyurethane with glycerin. The BIC was prepared from the reaction of trimethylol propane (TMP), toluene diisocyanate (TDI) and N‐methylaniline (NMA). The polyols and curing agent were characterized by conventional methods while the curing condition was optimized via gel content measurements. The curing kinetics of the polyurethane coating were investigated and the kinetic parameters derived. The crosslink densities of the samples were determined via the equilibrium swelling method, using the Flory–Rehner equation. The relationships between the crosslink density and the electrical, physical, mechanical and dynamic mechanical properties of the coatings were also studied. Copyright © 2005 Society of Chemical Industry
Computational analysis of 1‐methoxybicyclo[3.2.0]hepta‐3,6‐dien‐2‐one and its enantiomeric separation
Authors: Sohlberg Karl , Chen Yibai
Published: January 2005

A theoretical analysis of the primary photochemical products of irradiation of α‐tropolone methyl ether is presented. Through this analysis, the fact that only two of the four possible stereoisomers of the product are experimentally observed may be explained. We also present a computational scheme for identifying the enantiomers separated by chiral gas chromatography. Copyright © 2003 John Wiley & Sons, Ltd.
Involvement of adsorption effects in the TiO2‐sensitized photooxidation rate of benzylic derivatives in CH3CN
Authors: Giacco Tiziana Del , Rol Cesare , Sebastiani Giovanni V.
Published: January 2005

Competitive kinetic experiments in the TiO2‐sensitized photooxidation of some series of differently ring‐substituted benzylic derivatives (ArCHROR′) in aerated and/or deaerated CH3CN and in the presence of Ag2SO4 were carried out. From logkrel vs Ep plots it was hypothesized that a changeover of the electron abstraction site occurs on going from electron‐donating to electron‐withdrawing groups on the ring, from the aromatic moiety to the OCH3 group of benzyl methyl ethers, probably owing to the preferential adsorption of this group on TiO2 with respect to the aromatic ring. This phenomenon is not observed with benzyltrimethylsilanes because the orbital resulting from the overlap between the C— Si bond and the aromatic π system is the only adsorption site. The steric hindrance of an α‐methyl group (in benzylic alcohols) or a tert‐butyl group (in benzyl tert‐butyl ethers) reduces the degree of adsorption but does not influence the shape of the plot because OR′ should still be the preferential adsorption group. This also provides useful information about the surface structure of TiO2 suspended in CH3CN. Copyright © 2003 John Wiley & Sons, Ltd.
Description of covalent bond orders using the charge density topology
Authors: Howard Siân T. , Lamarche Olivier
Published: January 2005

Hybrid density functional calculations are employed to explore the relationships between covalent bond order, as defined using the atomic overlap matrix (AOM) formalisms developed by Cioslowski, Ángyán and others, and the parameters derived from a topological analysis of the electron density. Relationships are obtained for the specific cases of C—C, C—N, C—O, C—P and C—S bonds. The simple Pauling bond order–bond length relationship describes the data reasonably well in most cases, but the correlations show considerable scatter. Although no single parameter acts as a unified descriptor of bond order for all types of bond, in each case it is possible to find a model which describes the bond order data significantly better than the Pauling model based on bond length. The relationships presented can therefore be utilized to estimate rapidly the covalent part of the bond order from a topological analysis of the charge distribution for very large systems where the AOM‐based methods can become impractical to apply, and for charge density distributions which have been obtained from experiment (e.g. elastic x‐ray scattering). Copyright © 2003 John Wiley & Sons, Ltd.
Glyphosate‐resistant crops: history, status and future
Authors: Dill Gerald M
Published: January 2005

The commercial launch of glyphosate‐resistant soybeans in 1996 signaled the beginning of a new era in weed management in row crops. Today, over 80% of the soybeans grown in the USA are glyphosate resistant. Since that time, many crops have been transformed that have allowed crop applications of many classes of herbicide chemistries. Crops currently under production include maize, soybean, cotton and canola. Transformation technology and selection methods have improved and the rate of development as well as the breadth of crops being considered as commercial targets has increased. On the basis of recent adoption rates by growers around the world, it appears that glyphosate‐resistant crops will continue to grow in number and in hectares planted. However, global public acceptance of biotechnology‐derived products will continue to impact the rate of adoption of this and other new innovations derived from transformation technology. Copyright © 2005 Society of Chemical Industry
What it takes to get a herbicide's mode of action. Physionomics, a classical approach in a new complexion
Authors: Grossmann Klaus
Published: January 2005

Discovering new herbicides with novel modes of action is a priority assignment in plant protection research. However, for active compounds identified in greenhouse screens, the crucial point is to tread the most efficient path in determining a herbicide's target site, regarding chance of success, time and research costs. Today, in the literature, molecular (functional genomics, transcriptomics), biochemical (proteomics) and analytical (metabolomics) approaches are particularly discussed. So far, less attention has been focused on the comprehensive physiological profiling of the complex plant system as a procedure which enables new herbicides, with an unknown target site for their mode of action, to be screened rapidly. Here, the concept of an array of ‘functional’ bioassays is presented which has ultimately been developed from the classical tool of mode of action diagnosis by symptoms. These bioassays are designed to differentiate between the distinct responses of the multiple organization units (plant, tissue, meristematic cell, organelle), developmental stages, types of metabolism (phototrophic, heterotrophic) and physiological processes in the plant organism. The response pattern to a herbicide can be viewed as the end result of changes induced in the molecular and biochemical process chain and should be diagnostic of its physiological mode of action. The results can be interpreted directly or a fingerprint database for all known modes of action to be screened for analogy. The term ‘physionomics’ is proposed for this comprehensive physiological profiling of the plant system, following the parallel terminology of the molecular and biochemical ‘omics’ technologies. Physionomics procedures provide a first clue to the mode of action of a new herbicide that can direct more time‐consuming and costly molecular, biochemical, histochemical or analytical studies to identify a target site more efficiently. Copyright © 2005 Society of Chemical Industry
Field trials on the repellent activity of four plant products against mainly Mansonia population in western Ethiopia
Authors: Hadis Mamuye , Lulu Mesﬁn , Mekonnen Yared , Asfaw Teffera
Published: January 2005

The repellent activity of essential oils of lemon eucalyptus (Eucalyptus maculata citrodion), rue (Ruta chalepensis), oleoresin of pyrethrum (Chrysanthemum cinerariaefolium) and neem (Azadiracta indica) have been ﬁeld tested as 40%, 50% and 75% solutions in coconut oil against populations of mosquitoes consisting mainly of Mansonia in Gambella, western Ethiopia. A latin square design was used to randomize the test subjects for possible individual differences for mosquito attraction. Repellency was evaluated as the percentage protection. Deet was included in the study for comparison. All the plant products manifested repellency. At 50% concentration at which the highest repellency was recorded the protection was 91.6%, 87.0%, 96.0%, 97.9% for rue, neem, pyrethrum and deet, respectively. The essential oil of lemon eucalyptus was not tried at this concentration. At a 40% concentration deet, lemon eucalyptus and pyrethrum were signiﬁcantly (p < 0.05) more effective than rue and neem. At a 50% concentration, deet and pyrethrum were signiﬁcantly better (p < 0.05) than rue and neem. At a 75% concentration concentration, deet and lemon eucalypus performed signiﬁcantly better (p < 0.05) than pyrethrum and neem. The difference between pyrethrum and neem was also signiﬁcant (p < 0.01). Copyright © 2003 John Wiley & Sons, Ltd.
Reactions of (di)manganese carbonyl ions with 1,4,7‐trimethyl‐1,4,7‐triazacyclononane (Me3TACN) in the gas phase
Authors: van Beelen Eric S. E. , Ingemann Steen
Published: January 2005

The gas‐phase reactions of a series of (di)manganese carbonyl positive ions with 1,4,7‐trimethyl‐1,4,7‐triazacyclononane (Me3TACN) have been examined with the aid of Fourier transform ion cyclotron resonance (FTICR) mass spectrometry. The monomanganese carbonyl ions, [Mn(CO)n]+ (n = 2–5), react predominantly by ligand exchange and to a minor extent by electron transfer with the formation of the radical cation of Me3TACN. For the [Mn(CO)n]+ (n = 2–4) ions, the ligand exchange results in the exclusive formation of a [Mn(Me3TACN)]+ complex, whereas small amounts of [Mn(CO)(Me3TACN)]+ ions are also generated in the reactions of the [Mn(CO)5]+ ion. The [Mn2(CO)n]+ ions (n = 2, 4 and 5) react also by competing electron transfer and ligand exchange. The reaction of the [Mn2(CO)2]+ and [Mn2(CO)4]+ ions is associated with cleavage of the MnMn bond as evidenced by the pronounced formation of [Mn(Me3TACN)]+ ions. For [Mn2(CO)5]+, the ligand exchange leads mainly to the formation of [Mn2(CO)n(Me3TACN)]+ (n = 1–3) ions. These primary product ions react subsequently by the incorporation of a second Me3TACN molecule to afford [Mn2(CO)(Me3TACN)2]+ and [Mn2(CO)2(Me3TACN)2]+ ions. Both of these latter species incorporate an oxygen molecule with formation of ions with the assigned composition of [Mn2(O2)(CO)(Me3TACN)2]+ and [Mn2(O2)(CO)2(Me3TACN)2]+. Copyright © 2005 John Wiley & Sons, Ltd.