bluuebunny/crossref_metadata_2025 huggingface dataset:
Oligotrophic Bacteria
Authors: Koch Arthur L.
Published: November 2003

Paucity of Nutrients as a Severe Environment

What is an Oligotroph?

History of the Field

Classes of Oligotrophs

What Properties Must an Oligotroph Have?

Who Lives in Oligotrophic Environments and Who Does Not?

Physical Consideration for Survival Under Starvation or Oligotrophic Conditions

Diffusion Limitation of Uptake

Biological Considerations for Survival in a Nutritionally Poor Environment
Soil Enzymes
Authors: Tabatabai M. Ali
Published: November 2003

Factors Affecting Enzyme Reactions

Enzyme Inhibition

Enzymes in Soils

Factors Affecting Enzyme Activities in Soils
Toxoplasma Gondii
Authors: Dubey J. P.
Published: November 2003

Classification

Structure and Life Cycle

Cultivation, Molecular Biology, and Genetics

Host–Parasite Relationship

Infections in Humans

Infection in Animals Other Than Humans

Diagnosis

Treatment

Epidemiology

Prevention and Control
Bacteriophage of Enteric Bacteria: Occurrence and Persistance in the Environment
Authors: Yates Marylynn V.
Published: November 2003

Surrogates for Human Enteroviruses

Ecology of Bacteriophage

Persistence of Bacteriophages in the Environment
Periphyton
Authors: Cattaneo Antonella
Published: November 2003

Definition, Characteristics, and Development

Methods Used to Study Periphyton

Distribution in Different Habitats

Importance of Periphyton in the Metabolism and Food Web of Aquatic Ecosystems

Control of Periphyton Communities

Response of Periphyton to Anthropogenic Stresses
Activated Sludge Models: Microbiological Basis
Authors: Takashi Mino
Published: November 2003

History of IWA as Models

Basic Concepts of IWA as Models

Essential Processes in IWA Models

EBPR

Limitations and Future Perspectives of as Models
Neuston Microbiology: Life at the Air–Water Interface
Authors: Maki James S.
Published: November 2003

The Neuston

Sampling

The Nature of the Habitat: Model of the Structure

Bacterioneuston (Piconeuston)

Bacterioneuston and Environmental Stress

Other Microorganisms
Wetlands: Biodegradation of Organic Pollutants
Authors: D'Angelo Elisa
Published: November 2003

Wetland Biogeochemistry

Organic Pollutant Fate in Wetlands

Microbiological Transformation Reactions
Fuel Oxygenates, Microbial Degradation of
Authors: Salanitro Joseph P.
Published: November 2003

Introduction and Statement of the Problem

Properties of Oxygenates

Observations on the Microbial Metabolism of MTBE

Proposed Biodegradation Pathway for MTBE

Prospects and Challenges for the Bioremediation of Fuel Ethers
Polar Marine Phytoplankton
Authors: Holm‐Hansen Osmund , Sakshaug Egil
Published: November 2003

General characteristics of phytoplankton

Physical and chemical aspects of the Arctic and the Antarctic

Interannual variability: Importance of global cyclic climatic events

Rates of primary production

Major factors affecting growth rates of phytoplankton

Phytoplankton and the food web

Possible impacts of changing climatic conditions
Extracellular Enzymes in Biofilms
Authors: Wingender Jost , Jaeger Karl‐Erich
Published: November 2003

Secretion Mechanisms of Enzymes

Determination of Enzyme Activities in Biofilms

Distribution of Enzyme Activities in Biofilms

Influence of Environmental Factors on Enzyme Activity in Biofilms

Regulation of Extracellular Enzyme Activity in Biofilms

Functions of Extracellular Enzymes in Biofilms
Geochemical and Geological Significance of Subsurface Microbiology
Authors: Onstott Tullis
Published: November 2003

Background

Microbial Fluid Interactions

Microbial–Mineral Interactions
Red Tides and Other Harmful Algal Blooms
Authors: Steidinger Karen A.
Published: November 2003

The Causative Organisms (Algae)

Effects and Impacts (Harmful)

Blooms
Escherichia Coli: Pathogenic Strains
Authors: Rice E. W.
Published: November 2003

EnterohemorrhagicE. coli(EHEC)

EnteropathogenicE. coli(EPEC)

EnterotoxigenicE. coli(ETEC)

EnteroinvasiveE. coli(EIEC)
Activated Sludge—Microbiology of Nitrogen Removal
Authors: Schmidt Ingo , Strous Marc , Jetten Mike M. S.
Published: November 2003

The Biological Nitrogen Cycle

Oxidation of Ammonia

Anoxic Metabolism (Anoxic Ammonia Oxidation)

Anaerobic Ammonium Oxidation (Anammox)

Heterotrophic Ammonia Oxidation

Oxidation of Nitrite

Denitrification
Nitrification in Aquatic Systems
Authors: Ward B. B.
Published: November 2003

Physiology and Energetics of Nitrifying Bacteria

Phylogeny of Bacteria Involved in Nitrification

Role of Nitrification in the Nitrogen Cycle

Distribution and Abundance of Nitrifiers in Aquatic Habitats

Methods for Measuring Nitrification in Water and Sediments

Distribution of Nitrification in Water and Sediments

Environmental Variables that Affect Nitrification Rates and Distributions

Nitrous Oxide and Nitric Oxide Production During Nitrification

Nitrification and Methane Oxidation
Viruses in Drinking Water and Groundwater
Authors: Abbaszadegan Morteza
Published: November 2003

Viruses

Viruses in the Environment

Enteric Viruses in Water

Environmental Water Sampling Program

Conventional Cell Culture Assay

The Polymerase Chain Reaction Technique
Biochip‐Based Devices and Methods in Microbial Community Ribotyping
Authors: Tao Shengce , Cheng Jing , Ma Xuemei
Published: November 2003

Background of Microbial Community Ribotyping

Biochip‐Based Devices and Methods

The Applications of Biochips in Microbiology

Perspective

Acknowledgments
Activated Sludge—The Process
Authors: Lindrea K. C. , Seviour Robert J.
Published: November 2003

Features of the Process

Configurations for Activated Sludge Systems

Conventional Activated Sludge Systems

Activated Sludge Systems Designed to Remove Nitrogen

Activated Sludge Systems Designed to Remove Phosphorus

The Future for Activated Sludge Processes?
Nitrogen Cycle in the Marine Environment
Authors: Capone Douglas G.
Published: November 2003

Nitrogen Inputs and Outputs

Marine Nitrogen Pools

Processes

Concepts in Marine Nitrogen Cycle Dynamics

Contrasting Systems

Global Perspectives

How We Study the Nitrogen Cycle
Paleolimnology: Use of Algal Pigments as Indicators
Authors: Guilizzoni Piero , Lami Andrea
Published: November 2003

Pigments of Algae and Photosynthetic Bacteria

Preservation/Degradation of Pigments and its Paleolimnological Significance

Reconstructing Lake Acidity and Trophic Status

New Markers and Summary of the Pigment Proxy Records
Creating environments conducive for lifelong learning
Authors: Derrick M. Gail
Published: November 2003

Opportunities to engage in learning anytime or anywhere must address the issue of how to foster the desire for
sustained and enduring learning. The need to understand the conditions necessary for facilitating this type of
learning requires an understanding of the behaviors associated with autonomous learning coupled with
self‐efficacy beliefs.
An instructional strategy framework for online learning environments
Authors: Johnson Scott D. , Aragon Steven R.
Published: November 2003

The rapid growth of Web‐based instruction has raised many questions about the quality of online courses.
This chapter presents a conceptual framework that can guide the development of online courses by providing a
holistic perspective on online teaching and learning. Examples of instructional strategies that fit the framework
are described.
Compound Core–Shell Polymer Nanofibers by Co‐Electrospinning
Authors: Sun Z. , Zussman E. , Yarin A.L. , Wendorff J.H. , Greiner A.
Published: November 2003

Co‐electrospinning of core–shell polymer nanofibers (see Figure) is introduced. This process can be used for manufacturing of coaxial nanofibers made of pairs of different materials. Non‐spinnable materials can be forced into 1D arrangements by co‐electrospinning using a spinnable shell polymer. The method results in a novel two‐stage approach for fabrication of nanotubes instead of the previously used three‐stage process.
Studies on the electromagnetic interference shielding effectiveness of metallized PVAc‐AgNO3/PET conductive films
Authors: Huang Chueh‐Jung , Chang Teh‐Chou
Published: November 2003

A metal chelate polymer (MCP) of PVAc‐AgNO3 was prepared by adding AgNO3 salts into the PVAc matrix and was coated on to PET substrate to form PVAc‐AgNO3/PET films. These films were then treated with NaBH4 aqueous solution to become the reduced metallized conductive films (RMCF) of PVAc‐AgNO3/PET. The electromagnetic interference shielding effectiveness (EMI/SE) and the characteristics of these films were investigated. The SE value was measured by the far‐field transmission line method. The surface resistivity (Rs) of RMCF with a AgNO3 content of 15 wt % was found to be below 5 Ω/sq, and the SE value exceeded 20 dB over the frequency range 50–900 MHz. The Rs of RMCF with a AgNO3 content of 30 wt % was less than 1 Ω/sq, and the SE value even reached 33 dB at 550–650 MHz. It was confirmed by X‐ray and scanning electronmicroscope (SEM) analysis that the conducting network, as formed by closely deposited silver atoms on the reduced coating surface, was the dominant pathway for effective electron propagation that contributed to the excellent conductivity of these RMCF (PVAc‐AgNO3/PET). © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 270–273, 2004
Mesomorphic properties of cholesteric side‐chain liquid crystalline polysiloxanes and elastomers
Authors: Liu Lu‐Mei , Zhang Bao‐Yan , Cheng Chun‐Sheng , Zheng Ying‐Ying
Published: November 2003

A series of crosslinked liquid crystalline polymers and corresponding uncrosslinked liquid crystalline polymers were prepared by graft copolymerization. Their liquid crystalline properties were characterized by differential scanning calorimetry, polarizing optical microscopy, and X‐ray diffraction measurements. The results showed that the crosslinking obtained in the isotropic state and the introduction of nonmesogenic crosslinking units into a polymeric structure could cause additional reduction of the clearing point (Ti) of the crosslinked polymers, compared with the corresponding uncrosslinked polymers. The crosslinked polymers (P‐2–P‐4) with a low crosslinking density exhibited cholesteric phases as did the uncrosslinked polymers. In contrast, a high crosslinking density made the crosslinked polymer P‐5 lose its thermotropic liquid crystalline property. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 773–778, 2004
Optical switching behavior of polymer‐dispersed liquid crystal composite films with various novel azobenzene derivatives
Authors: Liu Jui‐Hsiang , Wang Hung‐Yu
Published: November 2003

Polymer‐dispersed liquid crystal (PDLC) composite films were fabricated by thermal polymerization with E7 liquid crystal, monomers, and novel azobenzene derivatives synthesized in this study. To investigate the effects of azocompounds on the optical switching of PDLC films, a series of novel azobenzene derivatives of 4‐alkyloxy‐4′‐methoxyazobenzene with carbon numbers of 3–6, chiral compounds of amyl‐4‐(4‐hexyloxyphenylazo)benzoate, and bornyl‐4‐(4‐hexyloxyphenylazo)benzoate were synthesized. The compounds synthesized in this investigation were identified using FTIR, NMR, and elemental analysis. The optical texture of the composite films was analyzed under crossed nicols with a polarizing microscope. The morphological observation of the solid polymer in the composite films was performed with a scanning electron microscope (SEM). The optical behavior of the composite films on UV irradiation and the effects of the curing time on the thermal stability of the composite films were investigated. Isomerization of the azobenzene derivatives due to UV irradiation was confirmed by a texture study and image recording method. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 789–799, 2004
New aspects of aging in epoxy networks. I. Thermal aging
Authors: Bockenheimer Clemens , Fata Davis , Possart Wulff
Published: November 2003

The thermal aging of an amine‐cured epoxy in the glassy state is studied for two network states by using DSC and attenuated total reflection‐infrared (IR‐ATR). The “low‐crosslinked” network possesses a relatively high molecular mobility and a considerable amount of residual reactive groups. In the low crosslinked matrix, the presence of high crosslinked regions is revealed. In contrast, the “highly crosslinked” epoxy system has a reduced molecular mobility and only small reactive groups. The high crosslinked matrix contains low crosslinked regions. Thermal loading for both networks is performed below their glass transition. During thermal aging, an ongoing curing reaction takes place in the low‐crosslinked epoxy. Thermooxidative degradation and the disintegration of short‐range ordering are observed as well. The highly crosslinked epoxy system undergoes a phase separation of relatively mobile segments in the low mobile matrix, which is a reversible process on heating. Thermooxidative degradation is also detected for this kind of network. In summary, for the “low” and the “highly” crosslinked epoxy, significant chemical and structural changes take place during thermal aging even though the networks are vitrified. It is convincing that these changes in the cured epoxy should exert an influence on the mechanical properties of a bonded structure. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 361–368, 2004
Synthesis and potential radical copolymerization of new monomers based on diallylguanidine
Authors: Zaikov G. E. , Malkanduev Yu. A. , Khashirova S. Yu. , Esmurziev A. M. , Martynenko A. I. , Sivova L. I. , Sivov N. A.
Published: November 2003

Methods were elaborated for the synthesis of new monomers, derivatives of diallylguanidine. These monomer salts (acetate and trifluoroacetates) have the ability to polymerize in water and organic solvents in the presence of radical initiators. Radical copolymerization of diallylguanidine and diallyldimethylammonium chloride was investigated. High biocide ability of obtained copolymers was demonstrated. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 439–444, 2004
Graded‐index plastic optical fiber with high mechanical properties enabling easy network installations. I
Authors: Ishigure Takaaki , Hirai Miki , Sato Masataka , Koike Yasuhiro
Published: November 2003

A doped poly(methyl methacrylate) (PMMA)–based graded‐index plastic optical fiber (GI POF) with high mechanical strength is reported for the first time. Although the POF is generally believed to have a good mechanical flexibility even if it has a large‐core diameter, such a high mechanical strength has been provided by making the polymer chains in the POF highly oriented in its axial direction. If such an orientation of polymer chains is eliminated, the POF becomes brittle, which is similar to silica‐based fibers. On the other hand, too high an orientation of the polymer chains induces fiber deformation in a high‐temperature atmosphere resulting from orientation relaxation. This study reports how high mechanical strengths such as the tensile strength and the large elongation are provided to the GI POF. By selecting the optimum heat‐drawing conditions, the GI POF has a mechanical strength comparable to that of the commercially available step index (SI) POF. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 404–409, 2004
Preparation of novel pyridine‐based, thermally stable poly(ether imide)s
Authors: Mehdipour‐Ataei Shahram , Heidari Hani
Published: November 2003

Two aromatic, pyridine‐based ether diamines were prepared by the nucleophilic aromatic substitution reaction of 4‐aminophenol and 5‐amino‐1‐naphthol with 2,6‐dichloropyridine in N‐methyl‐2‐pyrrolidone as a solvent. Polycondensation reactions of the obtained diamines with pyromellitic dianhydride, benzophenone tetracarboxylic dianhydride, and hexafluoroisopropylidene diphthalic anhydride resulted in six pyridine‐based, thermally stable poly(ether imide)s. The prepared monomers and polymers were characterized by common spectroscopic methods. The physical and thermal properties of the polymers, including the thermal behavior, thermal stability, solubility, and solution viscosity, were studied. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 22–26, 2004
Short sisal fiber‐reinforced tire rubber composites: Dynamic and mechanical properties
Authors: Martins M. A. , Mattoso L. H. C.
Published: November 2003

The world tendency toward using recycled materials demands new products from vegetable resources and waste polymers. In this work, composites made from powdered tire rubber (average particle size: 320 μm) and sisal fiber were prepared by hot‐press molding and investigated by means of dynamic mechanical thermal analysis and tensile properties. The effects of fiber length and content, chemical treatments, and temperature on dynamic mechanical and tensile properties of such composites were studied. The results showed that mercerization/acetylation treatment of the fibers improves composite performance. Under the conditions investigated the optimum fiber length obtained for the tire rubber matrix was 10 mm. Storage and loss moduli both increased with increasing fiber content. The results of this study are encouraging, demonstrating that the use of tire rubber and sisal fiber in composites offers promising potential for nonstructural applications. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 670–677, 2004
Nonisothermal crystallization of reprocessed poly(ethylene terephthalate)
Authors: Spinacé M. A. Silva , De Paoli M.‐A.
Published: November 2003

Poly(ethylene terephthalate) was submitted to five reprocessing cycles by extrusion. The materials were analyzed with oligomer and after oligomer extraction. The nonisothermal crystallization of the five samples was investigated by differential scanning calorimetry. Samples with oligomer content and carboxylic end group concentrations between 44 and 98 eqw × 106 g presented a nonlinear correlation with the crystallization temperature. After the oligomer extraction of the polymer, this correlation is linear. The nonisothermal crystallization results were analyzed using the Ozawa model. The polymers containing oligomers obey the Ozawa model for the first reprocessing cycle. After oligomer extraction, the polymers obey the Ozawa model from the first to the third reprocessing cycle. In both cases, the exponential n values are close to 2.0. For the other cycles, deviations from this model occur. The activation energy was calculated using the Kissinger and Varma models. The values obtained for the five reprocessed samples were inversely proportional to the molar mass when analyzed by both models. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 525–531, 2004
Effects of crosslinking agents, dyeing temperature, and pH on mechanical performance and whiteness of silk fabric
Authors: Leksophee T. , Supansomboon S. , Sombatsompop N.
Published: November 2003

The effects of bleaching and dyeing conditions on abrasion resistance, tear strength, and whiteness of silk fabrics were studied. Different crosslinking agents at various concentrations were introduced into the silk fabrics under various dyeing temperatures and pH. The results indicated that the oxidatively bleached silk fabric exhibited better mechanical properties than those of reductively bleached silk fabric. Sodium citrate was found to be the most suitable crosslinking agent for enhancing the abrasion resistance and tear strength of the silk fabrics with no significant effect on the whiteness. The mechanical property improvements of sodium citrate–dyed silk fabric were attributed to a chemical reaction between –COOH groups and amino acid side chains in silk fabric, the mechanism proposed in this work. Increasing sodium citrate resulted in improved mechanical properties and whiteness, but the opposite trend was found with increasing dyeing temperature. An optimum pH for dyeing the silk fabric in this work was 5.5. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 1000–1007, 2004
Grafting of acrylic monomers onto cotton fabric using an activated cellulose thiocarbonate–azobisisobutyronitrile redox system
Authors: Zahran M. K. , Morsy M. , Mahmoud R. I.
Published: November 2003

The feasibility of a cellulose thiocarbonate–azobisisobutyronitrile (AIBN) initiation system to induce graft copolymerization of methyl methacrylate (MMA) and other acrylic monomers onto cotton fabric was investigated. Other acrylic monomers were acrylic acid, acrylonitrile, and methyl acrylate. The initiation system under investigation was highly activated in the presence of a metal‐ion reductant or a metal‐ion oxidant in the polymerization medium. A number of variables in the grafting reaction were studied, including AIBN concentration, pH of the polymerization medium, nature of substrate, monomer concentration, duration and temperature of polymerization, and composition of the solvent/water polymerization medium. The solvents used were methanol, isopropanol, 1,4‐dioxane, cyclohexane, benzene, dimethyl formamide, and dimethyl sulfoxide. There were optimal concentrations of AIBN (5 mmol/L), MMA (8%), Fe2+ (0.1 mmol/L), Mn2+ (8 mmol/L), and Fe3+ (2 mmol/L). A polymerization medium of pH 2 and temperature of 70°C constituted the optimal conditions for grafting. The methanol/water mixture constituted the most favorable reaction medium for grafting MMA onto cotton fabric by using the Fe2+–cellulose thiocarbonate–AIBN redox system. MMA was superior to other monomers for grafting. The unmodified cotton cellulose showed very little tendency to be grafted with MMA compared with the chemically modified cellulosic substrate. A tentative mechanism for the grafting reaction was proposed. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 1261–1274, 2004
On‐line monitoring of the evolution of number of particles in emulsion polymerization by conductivity measurements. II. Model validation
Authors: Santos A. F. , Lima E. L. , Pinto J. C. , Graillat C. , McKenna T. F.
Published: November 2003

A model to describe the evolution of conductivity measurements in emulsion polymerizations was presented in the first part of this work [Santos et al., J Appl Polym Sci, 2002]. The model was built on the assumption that surfactant is partitioned among the three principle phases of the polymerizing latex. Model parameters were estimated by fitting the model responses to experimental conductivity data obtained in different runs performed with similar solids content, reactor temperature, and initiator concentration. A soft‐sensor strategy was then proposed for monitoring of the number of polymer particles (Np) by combining the conductivity model with the available conversion, temperature, and conductivity signals. The main objective of the current work is to validate the conductivity model in a broader range of operation conditions, to follow the evolution of Np (nucleation/coagulation) on‐line under different reaction conditions. A series of batch and semibatch polymerization runs were carried out aiming to evaluate the model performance when different solids content, surfactant concentration, and reactor temperatures are used. Additionally, simulation studies were performed to assess the model sensitivity to the fluctuations of the conversion and temperature signals. Results showed that the model is able to perform accurate predictions of Np even when disturbances of ±2°C in temperature and ±0.03 in monomer conversion take place during the polymerization process. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 941–952, 2004
Absorption characteristics of alginate wound dressings
Authors: Qin Yimin
Published: November 2003

This study describes an investigation on the absorption characteristics of alginate wound dressings. The fluid that is absorbed by the dressing is divided into that which is held inside the fiber in the fiber structure and that which is held between the fibers in the textile structure. A number of dressings with different fiber structure and textile structure were studied and their effects on the absorption characteristics of the dressings were analyzed. It was found that a significant part of the absorption took place inside the fiber structure, in addition to the liquid held between fibers in the textile structure. High M alginate and high G calcium/sodium alginate fibers absorbed more fluid into the fiber than high G calcium alginate fiber, resulting in a better gelling ability. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 953–957, 2004
Absolute online monitoring of acrylic acid polymerization and the effect of salt and pH on reaction kinetics
Authors: Çatalgil‐Giz Huceste , Giz Ahmet , Alb Alina M. , Reed Wayne F.
Published: November 2003

Using recently introduced Automatic Continuous Online Monitoring of Polymerization reactions (ACOMP), the kinetics of acrylic acid polymerization was studied. ACOMP yields the absolute weight‐averaged mass (Mw), monomer conversion, and other quantities. As the initiator concentration increased, it was shown that the rate increased and the Mw decreased as in regular free‐radical polymerization. The effect of salt on acrylic acid polymerization in an aqueous solution was investigated. The polymerization rate and Mw both decreased with an increasing salt concentration. ACOMP molecular weights were also compared with size‐exclusion chromatography on aliquots periodically withdrawn during the reaction, and good agreement was found. The effect of the pH on the rate and the molecular weight was also investigated, and when the medium pH was changed from 2 to 5 with sodium hydroxide, the rate and Mw both decreased as the pH increased. Light‐scattering results of reaction end products in the reference solvent showed that molecules synthesized at higher pH were in a more expanded form. When equimolar sodium hydroxide was added to the acrylic acid (pH ≅ 5) and sodium acrylate formed, adding salt did not effect the reaction kinetics of the poly(sodium acrylate); its effect on the products was a relatively minor decrease of Mw. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 1352–1359, 2004
Recombinant human elastin polypeptides self‐assemble into biomaterials with elastin‐like properties
Authors: Bellingham Catherine M. , Lillie Margo A. , Gosline John M. , Wright Glenda M. , Starcher Barry C. , Bailey Allen J. , Woodhouse Kimberly A. , Keeley Fred W.
Published: November 2003

Processes involving self‐assembly of monomeric units into organized polymeric arrays are currently the subject of much attention, particularly in the areas of nanotechnology and biomaterials. One biological example of a protein polymer with potential for self‐organization is elastin. Elastin is the extracellular matrix protein that imparts the properties of extensibility and elastic recoil to large arteries, lung parenchyma, and other tissues. Tropoelastin, the ≈70 kDa soluble monomeric form of elastin, is highly nonpolar in character, consisting essentially of 34 alternating hydrophobic and crosslinking domains. Crosslinking domains contain the lysine residues destined to form the covalent intermolecular crosslinks that stabilize the polymer. We and others have suggested that the hydrophobic domains are sites of interactions that contribute to juxtaposition of lysine residues in preparation for crosslink formation. Here, using recombinant polypeptides based on sequences in human elastin, we demonstrate that as few as three hydrophobic domains flanking two crosslinking domains are sufficient to support a self‐assembly process that aligns lysines for zero‐length crosslinking, resulting in formation of the crosslinks of native elastin. This process allows fabrication of a polymeric matrix with solubility and mechanical properties similar to those of native elastin. © 2003 Wiley Periodicals, Inc. Biopolymers 70: 445–455, 2003
Distribution of tyrosine hydroxylase, dopamine, and serotonin in the central nervous system of amphioxus (Branchiostoma lanceolatum): Implications for the evolution of catecholamine systems in vertebrates
Authors: Moret Frédéric , Guilland Jean‐Claude , Coudouel Sophie , Rochette Luc , Vernier Philippe
Published: November 2003

To investigate the evolutionary transition that has shaped the catecholaminergic systems of vertebrates, the organization of catecholamine‐synthesizing neurons and the nature of the catecholamines were examined in the central nervous system of adult amphioxus (Branchiostoma lanceolatum), a cephalochordate. We isolated a gene transcript encoding tyrosine hydroxylase (TH), the limiting enzyme of catecholamine biosynthesis, and studied its distribution together with that of dopamine and serotonin. Dopamine and TH are found in the same neurons of which they are three separate populations. Two are located in the anterior brain, the first being dorsal and lying in a row and the second being more posterior and lateral. A third population comprising a few dorsal commissural neurons was found in the posterior brain. The anterior dopaminergic cells innervate the ventral commissure of the cephalic vesicle, the hindbrain, and the spinal cord. A serotonin‐containing cell group is located in the same plane as the second dopaminergic cell population but is more caudal, marking the probable transition between anterior brain and hindbrain, as deduced from gene expression patterns. The overall distribution of dopaminergic and serotoninergic systems is similar in amphioxus and vertebrate central nervous system and could be an ancestral character of chordates. As assayed by high‐performance liquid chromatrography and electrochemical detection, significant amounts of dopamine and octopamine, but not of noradrenaline, are present in amphioxus head. This finding is consistent with data obtained from most prostomian species. We conclude that the noradrenergic system is probably an innovation of vertebrates that appeared along with the neural crest and specific hindbrain nuclei. J. Comp. Neurol. 468:135–150, 2004. © 2003 Wiley‐Liss, Inc.
Expression of the KCl cotransporter KCC2 parallels neuronal maturation and the emergence of low intracellular chloride
Authors: Stein Valentin , Hermans‐Borgmeyer Irm , Jentsch Thomas J. , Hübner Christian A.
Published: November 2003

Fast synaptic inhibition in the adult central nervous system (CNS) is mediated by GABA and glycine. During early development GABA acts as an excitatory neurotransmitter, which is deemed to be important for the maturation of the CNS. During development GABAergic responses undergo a switch from excitatory to inhibitory. This switch is correlated with upregulation of KCC2, the neuronal isoform of the potassium‐chloride cotransporter family. KCC2 lowers the intraneuronal chloride concentration below its electrochemical equilibrium. KCC2 activity is thought to depend on phosphorylation by endogenous tyrosine kinases. Here, we analyzed the expression pattern of KCC2 during murine embryonic and postnatal development by in situ hybridization and Western blot analysis. KCC2 expression paralleled neuronal differentiation and preceded the decline of the GABA reversal potential (EGABA) in spinal cord motoneurons and hippocampal pyramidal cells. The adult inhibitory response to GABA was established earlier in the spinal cord than in the hippocampus. Phosphorylated KCC2 protein was already present early in development when the functional GABA switch had not yet occurred. Thus, tyrosine‐phosphorylation seems to be less important than the transcriptional upregulation of KCC2. J. Comp. Neurol. 468:57–64, 2004. © 2003 Wiley‐Liss, Inc.
Characterization of dynamics and reactivities of solvated ions byab initiosimulations
Authors: Hofer Thomas S. , Tran Hung T. , Schwenk Christian F. , Rode Bernd M.
Published: November 2003

Based on a systematic investigation of trajectories ofab initioquantum mechanical/molecular mechanical simulations of numerous cations in water a standardized procedure for the evaluation of mean ligand residence times is proposed. For the characterization of reactivity and structure‐breaking/structure‐forming properties of the ions a measure is derived from the mean residence times calculated with different time limits. It is shown thatab initiosimulations can provide much insight into ultrafast dynamics that are presently not easily accessible by experiment. © 2003 Wiley Periodicals, Inc. J Comput Chem 25: 211–217, 2004
Conformational changes in poly(vinyl alcohol)‐graft‐polyacrylamide in aqueous solutions vs graft content
Authors: Kutsevol Nataliya , Zheltonozhskaya Tatyana , Melnik Nataliya , Guenet Jean‐Michel , Syromyatnikov Vladimir
Published: November 2003

Conformational changes have been studied in intramolecular polymer‐polymer complexes (intraPC) of graft copolymers of poly(acrylamide) and poly(vinyl alcohol) (PVA‐g‐PAA) with various numbers of grafts (4‐42) per molecule as a function of temperature and copolymer concentration. It is shown that the magnitude of conformational change depends on the grafts content while the temperature range over which the conformation changes occur is essentially determined by copolymer concentration. The conformational changes are reversible on heating and cooling.
Photo‐ageing of a thermoplastic aromatic polyurethane in contact with artificial sweat
Authors: Dubois Claude , Vebrel Joël , Rigny‐Bourgeois Valérie , Grohens Yves
Published: November 2003

An artificial photo‐ageing cell was adapted in order to study the behaviour of polymers partly immersed in artificial sweat. The goal was to select polymers and to transform them into objects that come in contact with the skin. The polymer studied in this paper is a thermoplastic aromatic polyurethane (TPU) with the following characteristics: soft, transparent, lightly yellow coloured and hypoallergenic. The ageing of this polymer was studied with or without the presence of light stabilizers, and with or without sweat.

The physico‐chemical changes in the TPU were analysed step by step during ageing. The differences in mass variation between the different ageing modes (with or without sweat; with or without stabilizers) provided information on the hydrolytic action of the sweat. The chemical changes that occurred around the irradiated or immersed surfaces were studied by IR‐ATR spectrometry in order to characterize the photo‐oxidation and hydrolytic effects as well as their coupling. The morphological modifications of the polymer were recorded by differential scanning calorimetry.
A comparative study of the rheological and structural properties of gelatin gels of mammalian and fish origins
Authors: Simon Anne , Grohens Yves , Vandanjon Laurent , Bourseau Patrick , Balnois Eric , Levesque Guy
Published: November 2003

From a long time, the traditional source of collagen has been mammals wastes, mainly bovine and porcine skins and bones. This study undertakes a comparative analysis of the viscoelastic behaviour and the structural properties of gelatin gels from both mammalian and fish origins.

All the rheological measurements were carried out within the linear viscoelastic region for gelatin gels and tentatively related to structural characteristics. At a given concentration the pig gelatine exhibits a high storage modulus, G′, which indicates that the gel is stiffer than the fish one. The helical structures content measured by the specific rotation, [α], is also higher for the pig gelatin. Moreover, the gel is denatured in the same range of temperature, namely, around 30°C but the transition is sharper for fish gelatine. These differences between the gelatins lie in the amino‐acid composition and molecular weight distribution which may influence the nature of the interchain junctions yielding to various gel mesostruture.
An energy–momentum conserving algorithm for non‐linear hypoelastic constitutive models
Authors: Noels L. , Stainier L. , Ponthot J. P.
Published: November 2003

This paper presents an extension of the energy momentum conserving algorithm, usually developed for hyperelastic constitutive models, to the hypoelastic constitutive models. For such a material no potential can be defined, and thus the conservation of the energy is ensured only if the elastic work of the deformation can be restored by the scheme. We propose a new expression of internal forces at the element level which is shown to verify this property. We also demonstrate that the work of plastic deformation is positive and consistent with the material model. Finally several numerical applications are presented. Copyright © 2003 John Wiley & Sons, Ltd.
Intercomparison of MSX/UVISI‐derived ozone and temperature profiles with ground‐based, SAGE II, HALOE, and POAM III data
Authors: Vervack Ronald J. , Yee Jeng‐Hwa , DeMajistre Robert , Swartz William H.
Published: November 2003

Recently, we demonstrated a combined extinctive and refractive stellar occultation technique on a proof‐of‐concept basis using data from the Ultraviolet and Visible Imagers and Spectrographic Imagers (UVISI) on the Midcourse Space Experiment (MSX) satellite. Beyond this initial presentation of the technique, we also used MSX/UVISI data obtained during the Stratospheric Aerosol and Gas Experiment III (SAGE III) Ozone Loss and Validation Experiment (SOLVE) campaign in 2000 to demonstrate the utility of stellar occultation data in scientific analyses. In the present work, we compare the retrieved ozone and temperature profiles from numerous MSX/UVISI stellar occultations to ground‐based, SAGE II, Halogen Occultation Experiment (HALOE), and Polar Ozone and Aerosol Measurement III (POAM III) data. The MSX/UVISI results derived using the combined occultation method are shown to compare favorably with all these data. Small biases in the comparisons hint at interesting differences in the nature of the various ozone measurement techniques, but the overall agreement in the comparisons clearly illustrates the utility of the combined technique as a complementary means of long‐term ozone monitoring.
A possible influence of the tropical quasi‐biennial oscillation on the variability of the extratropical circulation in the Southern Hemisphere
Authors: Raphael Marilyn
Published: November 2003

This study uses geopotential heights and zonal winds from the NCAR/NCEP Reanalysis, and the Naujokat tropical stratospheric zonal wind data set to evaluate the suggestion that the tropical quasi‐biennial oscillation (QBO) influenced the observed amplitude increase in zonal harmonic wave 1 in the Southern Hemisphere winter after 1975. Fourier analysis was used to extract zonal wave 1 (ZW1) from the geopotential heights. ZW1 and the zonal winds were stratified by QBO phase and compared to those composited for years before and after 1975. The comparisons confirm that ZW1, during the easterly phase of the QBO, is larger than ZW1 during the westerly phase. The comparisons also suggest that the growth in ZW1 seen after 1975 took place preferentially during winters with an easterly tropical QBO and weak stratospheric winds. The change in ZW1 is associated with surface level changes over the Pacific and simultaneous upper level support by the easterly phase tropical QBO.
New directions for family therapy: rubbish removal as a task of choice
Authors: Sutcliffe Pauline , Lovell Jane , Walters Marianne
Published: November 2003

Family therapy may be accompanied by laughter and wit as well as serious labour. Family life has a great deal to laugh about, and family therapists, if they take families seriously, need to be able to laugh and joke with them.
The repertory grid approach to analysing family members' perception of self and others: a pilot study
Authors: Gale Anthony , Barker Mary
Published: November 2003

We report a pilot study involving the administration of a questionnaire to family members, based upon the three key target dimensions of the distance regulation theory of Kan tor and Lehr (1975). The questions, concerning family relationships and personal attributes of family members, were based on constructs derived from the theory, and the responses of family members were in a form consistent with repertory grid analysis procedures. The method allows the family researcher or therapist to explore the organization of the constructs for each family member, showing how each member is construed both by others and by themselves.
Family assessment: a review
Authors: Wilkinson Ian
Published: November 2003

This article is a review of developments in the assessment of the family in recent years. The review is selective, in order to draw out certain themes and principles from the literature.
Refraining, metaphors, myths and fairy‐tales
Authors: Davies Evan
Published: November 2003

Consideration is given to the question as to whether the change produced by refraining is mere sophistry or reflects a more fundamental alteration in the way in which a situation is construed. However, such philosophical questions touching on the nature of reality can be avoided if actions, rather than the problematical situation, are made the subject of interest. The nature of metaphor is briefly explored, exhibiting the manner in which it may be regarded as an example of refraining. Myths and fairytales may be employed as extended metaphors and can then function as vehicles for refraining. As an illustration, a case of anorexia is described where refraining occurs around a fairy‐tale.
The reliability and validity of a system for family assessment
Authors: Wilkinson Ian Michael , Strattonf Peter
Published: November 2003

The Darlington Family Assessment System (DFAS) is based upon the principles of multisystem‐multimethod (MSMM) assessment. In practice it consists of a structured family interview with an integrated rating scale, a number of self‐report questionnaries, and a task with an integrated behaviour coding system. This article summarizes the results of a series of empirical evaluations of the DFAS, which concern evaluations of the system as an aid to clinical work with families and as a method for training (at a basic level) in family assessment. The results are presented in terms of their implications for the reliability and validity of the assessment system and discussed from the perspective of their generalizability.
Family therapy and ultra‐orthodox Jewish families: a structural approach
Authors: Wieselberg Huguette
Published: November 2003

Most ultra‐orthodox Jewish families live in tightly knit communities in which there is religious and cultural congruence between the structure of their communal organizations, their families, and the way individual members construe their world. Without excluding other family therapy models, this paper points to striking links between strictly orthodox Judaism and aspects of structural family therapy which suggest the latter may be particularly applicable to members of this ethnic minority. Therapeutic issues are illustrated with examples.
Management of childhood constipation: parents’ experiences
Authors: Farrell Mike , Holmes Gill , Coldicutt Pat , Peak Matthew
Published: November 2003

Background.  Constipation in childhood is common and places a burden on child health services. Whilst constipation can have a variety of causes, for most children it is usually non‐organic and requires limited intervention. It has been suggested that health professionals can resent consultations for such a common problem, believing them to be inappropriate. However, they can underestimate the impact of this condition, leading to adverse clinical effects, as well as parental dissatisfaction. Little research has explored parents’ experiences of consulting health professionals about the management of childhood constipation.

Aim.  To explore parents’ experiences of consulting health professionals about management of childhood constipation and to use the findings to inform more effective therapeutic encounters when responding to parental concerns.

Methods.  A phenomenological approach was adopted, using in‐depth interviews with parents of 14 children receiving health interventions for constipation.

Findings.  Six themes emerged from analysis including: ‘enduring and extreme constipation’, which reflected the substantial and sustained impact of the child's constipation; ‘dismissed and fobbed off’, which captured parents’ feelings that their concerns were frequently dismissed by health professionals; ‘asserting the need for action’, a perception that they had reached a point at which they had to demand some intervention; and ‘validation and acknowledgement’, which reflected acknowledgment that, finally, their concerns for their child had been taken seriously and acted on.

Discussion.  The findings indicate a failure by some health professionals to appreciate fully the significance of childhood constipation, thereby appearing to be unconcerned and insensitive to the needs of child and family. The impact of this is a potential loss of trust in health professionals by parents, which can then have implications for how they perceive and access health services for management of this common childhood problem. The findings offer an insight into parental experiences and indicate the need for a more sensitive approach during health consultations.
Effect of music on chronic osteoarthritis pain in older people
Authors: McCaffrey Ruth , Freeman Edward
Published: November 2003

Background.  Osteoarthritis is the most common degenerative disease in humans. It usually begins in middle age and is progressive. Chronic pain in older people presents a significant obstacle in maintaining function and independence. Previous studies have shown that music can improve motivation, elevate mood, and increase feelings of control in older people.

Purpose.  The purpose of this randomized clinical trial was to examine the influence of music as a nursing intervention on osteoarthritis pain in elders.

Method.  Data were collected using the short form of the McGill Pain Questionnaire with 66 elders suffering from chronic osteoarthritis pain. Differences in perceptions of pain were measured over 14 days in an experimental group who listened to music for 20 minutes daily and a control group who sat quietly for 20 minutes daily. All participants completed the Short Form McGill Pain Questionnaire (SF‐MPQ) on day 1, 7, and 14 of the study.

Results.  Results of t‐tests indicated that those who listened to music had less pain on both the Pain Rating Index on day 1 (P = 0·001), day 7 (P = 0·001) and day 14 (P = 0·001) and on the Visual Analogue Scale on day 1 (P = 0·001), day 7 (P = 0·001) and day 14 (P = 0·001), when compared with those who sat quietly and did not listen to music. A repeated measure analysis of variance controlling for pretest measures demonstrated a significant decrease in pain among experimental group participants when compared with the control group on the pain descriptor section of the SF‐MPQ (P = 0·001) and the visual analogue portion of the SF‐MPQ (P = 0·001).

Conclusion.  Listening to music was an effective nursing intervention for the reduction of chronic osteoarthritis pain in the community‐dwelling elders in this study.
Canine Osteosarcoma of the Penile Bone
Authors: Bleier T. , Lewitschek H. P. , Reinacher M.
Published: November 2003

A 13‐year‐old mixed breed dog was presented with difficulties to urinate, blood in the urine and a nodule at the root of the penis. The penis was completely resected, and an osteosarcoma of the penile bone was diagnosed. Radiographically, there was no evidence to suggest tumours in other bones or distant metastases. The dog was euthanized as a consequence of tumour recurrence after 2 months. This is believed to be the first reported case of a primary osteosarcoma of the penile bone.