bluuebunny/crossref_metadata_2025 huggingface dataset:
Gefitinib Therapy for Advanced Non–Small-Cell Lung Cancer
Authors: Liu Chin Y , Seen Susan
Published: October 2003

OBJECTIVE:

To review the pharmacology, pharmacokinetics, clinical efficacy, and toxicity of gefitinib in non–small-cell lung cancer (NSCLC).

DATA SOURCES:

Primary literature search through MEDLINE and CANCERLIT, and abstract presentations (1966–May 2003).

STUDY SELECTION AND DATA EXTRACTION:

All published trials and abstracts citing gefitinib were evaluated, and all information deemed relevant was included in this article.

DATA SYNTHESIS:

NSCLC is known to overexpress epidermal growth factor receptor (EGFR). Gefitinib is a selective EGFR tyrosine kinase inhibitor. Based on the Phase I/II trial results, the optimal dose is 250 mg/d orally. It is well tolerated, with minimal and reversible toxicity. Skin rash and diarrhea are the most common adverse effects. Recent trials have shown that gefitinib provided a 10% tumor response rate and improved disease-related symptoms in patients with refractory, advanced NSCLC.

CONCLUSIONS:

Gefitinib, with a unique mechanism of action and favorable toxicity profile, has demonstrated clinical activity in NSCLC patients with chemotherapy-refractory disease. It provides a valuable addition to the treatment options as monotherapy in patients with advanced NSCLC after failure of both platinum-based and docetaxel chemotherapies. Further research is required to evaluate the use of gefitinib in different clinical settings.
Ultraviolet weathering of photostabilized wood‐flour‐filled high‐density polyethylene composites
Authors: Stark Nicole M. , Matuana Laurent M.
Published: September 2003

Wood‐plastic composites are being increasingly examined for nonstructural or semistructural building applications. As outdoor applications become more widespread, durability becomes an issue. Ultraviolet exposure can lead to photodegradation, which results in a change in appearance and/or mechanical properties. Photodegradation can be slowed through the addition of photostabilizers. In this study, we examined the performance of wood flour/high‐density polyethylene composites after accelerated weathering. Two 24 factorial experimental designs were used to determine the effects of two hindered amine light stabilizers, an ultraviolet absorber, a colorant, and their interactions on the photostabilization of high‐density polyethyl‐ ene blends and wood flour/high‐density polyethylene composites. Color change and flexural properties were determined after 250, 500, 1000, and 2000 h of accelerated weathering. The results indicate that both the colorant and ultraviolet absorber were more effective photostabilizers for wood flour/high‐density polyethylene composites than the hindered amine light stabilizers. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 2609–2617, 2003
Development of pendant drop mechanical analysis as a technique for determining the stress–relaxation and water‐permeation properties of interfacially polymerized barrier layers
Authors: Khare Vivek P. , Greenberg Alan R. , Krantz William B.
Published: September 2003

Interfacial polymerization (IP) involves the formation of solid polymeric films at the interface between aqueous and immiscible organic solutions via an interfacial polycondensation reaction between complementary monomeric reactants present in the two solutions. IP films are very thin (<0.25 μm) and form effective barrier layers in interfacially polymerized thin‐film composite membranes. Considerable difficulties are encountered in applying conventional characterization techniques to such unsupported IP thin films. This article describes the development of a novel technique, pendant drop mechanical analysis (PDMA), which can be used to study the mechanical and transport behavior of unsupported IP films. Experiments were conducted on films formed in a PDMA apparatus via the IP polymerization of m‐phenylene diamine and trimesoyl chloride (TMC). Stress–relaxation data obtained via PDMA were fitted with the Williams–Watts equation, and the results indicated a statistically significant dependence of the model parameters on the TMC concentration. Permeation experiments also demonstrated a statistically significant dependence of the membrane constant on the TMC concentration. The results provide unique insights regarding the relationship between structure and performance in unsupported IP films and suggest that network formation is enhanced in a concentration range of 0.1–0.3 wt % TMC. Although refinements are required, PDMA appears to be a promising technique for identifying optimum IP reaction conditions and assessing corresponding mechanical and transport characteristics. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 2618–2628, 2003
Topology‐rheology regression models for monodisperse linear and branched polyethylenes
Authors: Bonchev Danail , Dekmezian Armenag H. , Markel Eric , Faldi Alessandro
Published: September 2003

Several quantitative descriptors of polymer topology—the Wiener numberW, complexity index K, and the index of 3‐starnessS—were shown to relate well the measured rheological properties of linear and 3‐arm star monodisperse polyethylene samples to their structure. The complexity indexK(the substructure count) provided single‐variable models with correlation coefficientsrranging from 0.95 to 0.98 for zero‐shear viscosity, activation energy, and the parameters λ and α from the Cross equation, which describes the shape of the viscosity/shear rate curve. The regression models with two and three topological variables were characterized byr> 0.99 and low standard deviations. The models were used to predict the values of these rheological parameters for branched monodisperse polyethylenes not yet synthesized, thus indicating the potential of this topology‐based methodology for industrial applications. The study also presents a statistical confirmation for the much stronger effect that long‐chain branching has on shear rheology than that of molecular weight. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 2648–2656, 2003
Wood flour: A new filler for the rubber processing industry. I. Cure characteristics and mechanical properties of wood flour‐filled NBR and NBR/PVC compounds
Authors: Vladkova T. , Vassileva St. , Natov M.
Published: September 2003

In this study, conifer wood flour was evaluated as a filler to NBR or NBR/PVC compounds studying it influence on their cure characteristics and mechanical properties. It was shown that the filling by wood flour offers a possibility to obtain high modulus high elastic or less elastic or rigid wood like vulcanizates by varying of both the filling level and NBR/PVC mass ratio.It was established that in contrary to the mineral fillers usually causing significant delay of the vulcanization process, the wood flour shows a tendency to reduce the optimum cure time, τ90. Modulus M100 and Shore hardness of the wood flour‐filled vulcanizates of NBR or NBR/PVC compounds in which NBR is predominant, increase in a compliance with the increase of Mmax and DM when the filling level increases. The dependence is other when NBR and PVC are in equal amounts or PVC predominates. As a most probable explanation of the effect of the wood flour on the cure characteristics is accepted, the influence of the wood flour polar groups as well as of the presenting as wood flour humidity water molecules, the specific mechanical properties of the wood flour‐filled NBR or NBR/PVC compounds could be connected (to some extend) with a specific interface interaction between the wood flour particles and the polymer matrix. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 2734–2739, 2003
Heating characteristics and polymerization of ε‐caprolactone under microwave irradiation
Authors: Liao L. Q. , Liu L. J. , Zhang C. , He F. , Zhuo R. X.
Published: September 2003

The thermal effect of microwave energy on ε‐caprolactone (CL) monomer and polymerization reaction mixture of CL with stannous octoate [Sn(Oct)2] intimately depended on the power level of microwaves and the mass scale of materials. When 10 g of CL was heated by microwaves at a power of 680 W, its temperature increased rapidly from 20 to 355°C within 5 min after which it was self‐regulated to keep constant at 360°C. Heat generation was observed when a polymerization reaction mixture of 10 g CL with 0.1% (mol/mol) Sn(Oct)2 was irradiated at 680 W. The exothermic peak was recorded at 2–5 min and its temperature was over 300°C, with the maximum at 343°C. During this period the ring‐opening polymerization of CL occurred quickly, resulting in poly(ε‐caprolactone) with weight‐average molecular weight (Mw) of 123,000 g/mol and yield of 95%. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 2657–2664, 2003
The effect of fiber orientation on the toughening of short fiber‐reinforced polymers
Authors: Norman David A. , Robertson Richard E.
Published: September 2003

The effect of fiber orientation on the toughening of polymers by short glass fibers generally below their critical length was investigated using specimens with either well‐aligned or randomly oriented fibers. The fibers were aligned by an electric field in a photopolymerizable monomer, which was polymerized while the field was still being applied. These materials were fractured with the aligned fibers in three orientations with respect to the crack plane and propagation direction. Specimens with fibers aligned normal to the fracture plane were the most tough, those with randomly oriented fibers were less tough, and those with fibers aligned within the fracture plane were the least tough. The fracture behaviors compared favorably with predictions based on observed processes accounting for fiber orientation. The processes considered were fiber pull‐out (including snubbing), fiber breakage, fiber–matrix debonding, and localized matrix‐yielding adjacent to fibers bridging the fracture plane. Fibers not quite perpendicular to the fracture plane provided the greatest toughening; these fibers pulled out completely and gave a significant contribution from snubbing. Fibers at higher angles provided less toughening, involving nearly equal contributions from pull‐out, breakage, and debonding. Fibers within the fracture plane provided the least toughening, involving debonding alone. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 2740–2751, 2003
Mass transfer characteristics of natural rubber/ethylene vinyl acetate blends
Authors: Sujith A. , Radhakrishnan C. K. , Unnikrishnan G. , Thomas Sabu
Published: September 2003

The transport behavior of natural rubber/ethylene vinyl acetate (NR/EVA) blends has been investigated using aromatic hydrocarbons as probe molecules, in the temperature range of 26–56°C. It has been observed that the solvent uptake decreases with increase in the EVA content of the blends. The blends were crosslinked by three systems, viz. sulfur, dicumyl peroxide (DCP), and a mixture consisting of sulfur and peroxide. The DCP crosslinked system exhibited the lowest solvent uptake. The differences in the transport behavior of the blends, crosslinked by different modes, has been described in terms of the nature of crosslinks introduced between the macromolecular chains during vulcanization. The mechanism of transport has been found to deviate from the regular Fickian behavior, observed with conventional rubbers, with an increase in EVA in the blends. The dependence of the transport coefficients on blend composition, crosslinking systems, nature of penetrants, and temperature was studied. The blend–solvent interaction parameter, enthalpy, and entropy of sorption have also been estimated from the transport data. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 2691–2702, 2003
Effect of hydrophilicity on the biodegradability of polyesteramides
Authors: Park Chunghee , Kim Eun Young , Yoo Young Tai , Im Seung Soon
Published: September 2003

The effect of surface hydrophilicity was induced from the amide units in the polyesteramide. The surface energies and compositions of the polyesteramides were studied by employing contact angle and interfacial tension measurements and ESCA analysis. Biodegradability was evaluated form various methods including activated sludge test, enzyme hydrolysis, and soil burial test, which determine the amount of evolved CO2, weight loss, and TOC values, respectively. It was found that the introduction of amide groups to the aliphatic polyester improved the biodegradability, although the increase of biodegradation rate was not directly proportional to the amide content. The biodegradability of aliphatic polyesters increased with the addition of amide functionality. Therefore, it can be concluded that the addition of appropriate contents of hydrophile enhanced the biodegradability of aliphatic polyesters as well as their physical properties. Also, the experimental results revealed the relation between hydrophilicity and biodegradability of polyesteramides. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 2708–2714, 2003
Proton conducting materials based on thermoplastic elastomers silica composites
Authors: Acosta J. L. , González L. , Ojeda M. C. , Del Río C.
Published: September 2003

In this research, ionomeric composites based on organophilized silica (SIL) and a thermoplastic elastomer (HSBR), were prepared and characterized from a microstructural and electrical point of view. DSC was used to confirm silica sulfonation and FTIR to characterize the polymer before and after sulfonation reaction. DSC and DMA analysis show thatTgHPBremains constant in all the samples studied.TgPSmeasured through DMA presents an increase of about 40°C in the sample containing both the sulfonated filler and the sulfonated polymer matrix. The resulting materials can be easily processed to yield thin films (thickness 0.2–0.4 mm) with outstanding proton conducting properties (10−2S · cm−1). The suitability for film formation and good electrical properties is indicative of their potential use as electrolytes in polymer fuel cells. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 2715–2720, 2003
Synthesis, characterization, and thermal properties of copolymers of behenyl acrylate and behenyl fumarate
Authors: Sarmah Diganta , Baruah Shashi D.
Published: September 2003

Radical copolymerization of behenyl (systematic IUPAC nomenclature: n‐docosyl) acrylate and behenyl fumarate has been carried out in toluene at 70°C using benzoyl peroxide as initiator. Gel permeation chromatography was used to determine molecular weights (MW) and molecular weight distribution (MWD) of behenyl acrylate–behenyl fumarate (BA‐BF) copolymers. 1H NMR and carbon analysis was used to determine the composition of BA‐BF copolymers. Monomer reactivity ratios for high conversion polymerization were calculated by conversion‐extended Kelen‐Tudos plot. Differential scanning calorimetric (DSC) measurements shows sharp melting peaks at about 64°C. Thermal stability studies were performed with thermogravimetric analyzer (TGA). By using these DSC and TGA data in several nonisothermal methods, the activation energies were calculated. X‐ray diffraction studies show the linearity of the copolymers. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 2721–2726, 2003
Thermal and mechanical characterization of linear low‐density polyethylene/wood flour composites
Authors: Marcovich Norma E. , Villar Marcelo A.
Published: September 2003

A linear low‐density polyethylene (LLDPE) matrix was modified with an organic peroxide and by a reaction with maleic anhydride (MAn) and was simultaneously compounded with untreated wood flour in a twin‐screw extruder. The thermal and mechanical properties of the modified LLDPE and the resulting composites were evaluated. The degree of crystallinity was reduced in the modified LLDPE, but it increased with the addition of wood flour for the formation of the composites. Significant improvements in the tensile strength, ductility, and creep resistance were obtained for the MAn‐modified composites. This enhancement in the mechanical behavior could be attributed to an improvement in the compatibility between the filler and the matrix. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 2775–2784, 2003
Water‐dispersible porous polyisoprene‐block‐poly(acrylic acid) microspheres
Authors: Lu Zhihua , Liu Guojun , Liu Futian
Published: September 2003

Two polyisoprene‐block‐poly(tert‐butyl acrylate) (PI‐b‐PtBA) samples and a poly(tert‐butyl acrylate) (PtBA) homopolymer (hPtBA) were prepared by anionic polymerization and characterized by light scattering, size exclusion chromatography, and NMR. The tert‐butyl groups were removed from one of the diblocks to yield amphiphilic polyisoprene‐block‐poly(acrylic acid) (PI‐b‐PAA). PI‐b‐PAA was then used as the surfactant to disperse dichloromethane containing PI‐b‐PtBA and hPtBA at different weight ratios as oil droplets in water. Solid microspheres containing segregated polyisoprene (PI) and PtBA/hPtBA domains were obtained after dichloromethane evaporation. Permanent microspheres were obtained after PI domain crosslinking with sulfur monochloride. Porous microspheres were produced after the hydrolysis of PtBA and the extraction of the homopoly(acrylic acid) chains. The shape and connectivity of the poly(acrylic acid)‐lined pores were tuned by changes in the PtBA/hPtBA content in the precursor microspheres. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 2785–2793, 2003
Characterization and physical properties of polymethylphenylsilsesquioxane (PMPSQ) and hydroxyl‐functionalized polystyrene (PS–OH) hybrids
Authors: Hong Seungpyo , Hong Soon Man , Hwang Seung Sang , Kim Byoung Chul
Published: September 2003

Polymethylphenylsilsesquioxane (PMPSQ–OH) and trimethylsilyl end‐blocked PMPSQ (PMPSQ–EC) were prepared. The thermal decomposition behavior of these polymers was studied by thermogravimetric analysis (TGA) and FT‐Raman spectroscopy. Hydroxyl‐functionalized polystyrene (PS–OH) was also prepared by anionic living polymerization. Thin hybrid films of PMPSQ/PS–OH with various blend ratios were obtained by spin‐coating on freshly cleaned glass. The surface morphology of the hybrid films was investigated by atomic force microscopy (AFM). In 80/20 PMPSQ/PS–OH hybrid film, the PS–OH component produced a very uniformly dispersed phase. This hybrid film contained small domains of PS–OH whose size ranged from 60 to 80 nm. As the content of PS–OH was increased, the domain morphology coarsened and phase inversion took place around 50 wt %. In the phase‐inversed system, the PMPSQ‐rich phase was uniformly distributed in the PS–OH‐rich continuous phase. In addition, temperature‐dependent dielectric properties of PMPSQ/PS–OH hybrids were investigated. Relaxation of the hybrids was observed with an increasing content of the PS–OH component due to the amorphous glass transition behavior of PS–OH. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 2801–2812, 2003
Synthesis and characterization of iron carbonyl‐modified hydroxyl‐terminated polybutadiene: A catalyst‐bound propellant binder for burn‐rate augmentation
Authors: Subramanian K. , Sastri K. S.
Published: September 2003

Iron was coordinately linked to the hydroxyl‐terminated polybutadiene (HTPB) backbone using iron carbonyl via a ligand displacement reaction. The modified HTPB thus obtained was reddish brown in color and was characterized by GPC, FTIR, NMR, thermal, and propellant studies. No significant changes in the rheology, molecular weight, and molecular weight distribution were seen in the modified resin when the bonded Fe content was >0.8.0 wt %. However, the hydroxyl value of the resin decreased by 3–7 irrespective of the weight percent of the bonded Fe, and this was more likely due to the Fe‐catalyzed oxidation of the CH2OH moiety, mostly to the CHO group. Apparently, this has not affected the cure characteristics of the binder, as demonstrated by the good mechanical properties of the gum stock and the propellant. The catalytic efficiency of the bonded Fe on the burn rate of the propellant was more efficient than was the free Fe added to the propellant. The aging characteristics of the resin for the bound iron content of ≤0.8 wt % was apparently good, as its viscosity and molecular weight did not undergo any drastic changes even after 18 months' storage under ambient conditions. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 2813–2823, 2003
Synthesis, properties, and dyeing application of nonionic waterborne polyurethanes with different chain length of ethyldiamines as the chain extender
Authors: Yen Meng‐Shung , Chen Pei‐Yu , Tsai Hsiang‐Chin
Published: September 2003

This study deals with the synthesis of some nonionic waterborne polyurethanes (PUs), using ethyldiamines of different chain length, such as ethylenediamine (EDA) and diethyltriamine (DETA), as the chain extender in the reaction, and examines the thermal properties, mechanical properties, and dyeing properties of the PU products and their blends. As far as each PU by itself is concerned, we found that the Tg of the one made with DETA is the highest, followed by that with EDA, and the one with 1,4‐butanediol (1,4‐BD) is the lowest. The PU made with 1,4‐BD as the chain extender has no Tm, while the two others, using diamines as chain extenders, have a clear Tm, the one with DETA being higher than that with EDA. However, the enthalpy data are just the opposite. The tensile strengths of the two PUs, made with diamines as the chain extender, are larger than that made with 1,4‐BD, but their respective elongation properties are just the opposite. A comparison within PUs made with diamines showed that the one made with EDA is greater in both strength and elongation categories than that made with DETA. However, the one made with DETA is far superior to both of those made with 1,4‐BD and EDA in their dye‐exhaustion ratio, color yield (K/S), fixation rate, and color fastness. In respect to the various PU mixtures that we examined, we found that both PUs synthesized with EDA or DETA as the chain extender would have their Tg's greatly increased by blending in some PU made using 1,4‐BD as the chain extender. Among them, in particular, a blend of PU, made separately with DETA and 1, 4‐BD as the chain extender, showed great improvements in both tensile strength and elongation and also demonstrated better dyeability. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 2824–2833, 2003
Preparation of a novel metal‐chelate affinity beads for albumin isolation from human plasma
Authors: Odabaşi Mehmet , Garipcan Bora , Denizli Adil
Published: September 2003

In this study, we developed a novel approach to obtain a high protein‐adsorption capacity utilizing 2‐methacryloylamidohistidine (MAH) as a biollgand. MAH was synthesized by reacting methacryloyl chloride and histidine. Spherical beads, with an average size of 150–200 μm, were obtained by the radical suspension polymerization of MAH, ethyleneglycol dimethacrylate (EGDMA), and 2‐hydroxyethyl methacrylate (HEMA) conducted in an aqueous dispersion medium. p(EGDMA–HEMA–MAH) beads had a specific surface area of 17.6 m2/g. The synthesized MAH monomer was characterized by NMR. p(EGDMA–HEMA–MAH) beads were characterized by a swelling test, FTIR, and elemental analysis. Then, Cu(II) ions were incorporated into the beads and Cu(II) loading was found to be 0.96 mmol/g. These beads, with a swelling ratio of 65% and containing 1.6 mmol MAH/g, were used in the adsorption/desorption of human serum albumin (HSA) from both aqueous solutions and human serum. The adsorption of HSA onto p(EGDMA–HEMA–MAH) was low (8.8 mg/g). Cu(II) chelation onto the beads significantly increased the HSA adsorption (56.3 mg/g). The maximum HSA adsorption was observed at pH 8.0 Higher HSA adsorption was observed from human serum (94.6 mg HSA/g). Adsorptions of other serum proteins were obtained as 3.7 mg/g for fibrinogen and 8.5 mg/g for γ‐globulin. The total protein adsorption was determined as 107.1 mg/g. Desorption of HSA was obtained using a 0.1M Tris/HCI buffer containing 0.5M NaSCN. High desorption ratios (to 98% of the adsorbed HSA) were observed. It was possible to reuse Cu(II)‐chelated p(EGDMA–HEMA–MAH) beads without significant decreases in the adsorption capacities. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 2840–2847, 2003
Study of radiation‐induced graft copolymerization of butyl acrylate onto chitosan in acetic acid aqueous solution
Authors: Yu Li , He Yu , Bin Liang , Yue'e Fang
Published: September 2003

The graft copolymerization of butyl acrylate onto chitosan in acetic acid aqueous solution was investigated, using the γ‐ray of 60Co γ‐irradiation method. Fourier transform infrared spectra analysis, X‐ray diffraction analysis, and scanning electron microscopy characterized the graft copolymer. The effect of synthesis variables in the graft copolymerization have been discussed in the light of grafting efficiency, grafting percentage, and homopolymer percentage. Hydrophilicity and impact strength of the films formed from copolymer solution were tested and their feasibility as seed coating was studied. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 2855–2860, 2003
Effect of compatibilizer in acrylonitrile‐butadiene‐styrene toughened nylon 6 blends: Ductile–brittle transition temperature
Authors: Araújo E. M. , Hage E. , Carvalho A. J. F.
Published: September 2003

The ductile–brittle transition temperatures were determined for compatibilized nylon 6/acrylonitrile‐butadiene‐styrene (PA6/ABS) copolymer blends. The compatibilizers used for those blends were methyl methacrylate‐co‐maleic anhydride (MMA‐MAH) and MMA‐co‐glycidyl methacrylate (MMA‐GMA). The ductile–brittle transition temperatures were found to be lower for blends compatibilized through maleate modified acrylic polymers. At room temperature, the PA6/ABS binary blend was essentially brittle whereas the ternary blends with MMA‐MAH compatibilizer were supertough and showed a ductile–brittle transition temperature at −10°C. The blends compatibilized with maleated copolymer exhibited impact strengths of up to 800 J/m. However, the blends compatibilized with MMA‐GMA showed poor toughness at room temperature and failed in a brittle manner at subambient temperatures. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 2643–2647, 2003
Ripening time and fiber formation of chitosan spinning dope
Authors: Lee Shin‐Hee
Published: September 2003

A study was carried out on the wet spinning of chitosan fibers using 2% acetic acid as a solvent, 10% aqueous sodium hydroxide as a nonsolvent, and 4% chitosan solution as a polymer concentration. In this study, we investigated the effect of the ripening time of the spinning dope on the ability of fiber formation (i‐value), structure, thermal, and mechanical properties (such as fineness, tenacity, elongation, work of rupture, etc.) of chitosan fibers. Based on the results, it can be seen that the ripening time of spinning dope (in days), with the same polymer concentration of spinning dope, changes from 1 to 8, and the i‐value of the spinning dope increased with an increasing of the ripening time. At the ripening time of 8 days, tensile strength, elongation, and work of rupture showed minimum value attributed to the excessive degradation of the chitosan polymer chains left from the mixing operation that took place at the same time as the ripening time of the spinning dope, which means that the optimum ripening time of the spinning dope is 1 to 7 days. However, the thermal decomposition temperature and the onset of the exothermic temperature of thermal properties decreased with an increased ripening time. On the other hand, tenacity, elongation, and toughness decreased with increasing ripening time, and these qualities radically decreased with an increasing ripening time of more than a week. This indicates that the dispersion of aggregates and the degradation of chitosan polymer chains left from the mixing operation occurred at the same time during the ripening time of the spinning dope. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 2870–2877, 2003
Expression of tryptophan 5‐hydroxylase gene during sea urchin neurogenesis and role of serotonergic nervous system in larval behavior
Authors: Yaguchi Shunsuke , Katow Hideki
Published: September 2003

Tryptophan 5‐hydroxylase (TPH) is the rate‐limiting enzyme in the biosynthesis of serotonin. cDNA cloning of TPH was carried out, and the occurrence of spatiotemporal transcription of TPH message was examined in larvae of the sea urchin, Hemicentrotus pulcherrimus (HpTPH), with in situ hybridization by using the tyramide signal amplification (TSA) technique and Northern hybridization. Based on deduced amino acids sequence of HpTPH, phylogenetically sea urchin locates at the closest position to vertebrates among invertebrates, and HpTPH had common conserved sequences in a catalytic domain. Initiation of HpTPH transcription occurred at the late gastrula stage exclusively in serotonin cells of apical ganglion (SAG) that was composed of a cluster of HpTPH‐positive cells and the negative cells in between. In situ hybridization showed that the mRNA expression pattern was similar to the immunohistochemical localization of serotonin cells reported before (Bisgrove and Burke [1986] Dev. Growth Differ. 28:557–569; Yaguchi et al. [2000] Dev. Growth Differ. 42:479–488). p‐Chlorophenylalanine (CPA), an irreversible inhibitor of TPH activity, considerably decreased serotonin content in the serotonin cells, whereas the HpTPH expression pattern and timing, and the extension of neurofibers from SAG cells were apparently unaffected, suggesting CPA exclusively perturbed synthesis of serotonin but not nervous system organization. CPA‐treated larvae did not swim, despite the occurrence of ciliary beating in culture chamber, suggesting that proper serotonin synthesis is necessary for normal swimming of the larvae. J. Comp. Neurol. 466:219–229, 2003. © 2003 Wiley‐Liss, Inc.
Organization and development of corticocortical associative neurons expressing the orphan nuclear receptor Nurr1
Authors: Arimatsu Yasuyoshi , Ishida Mami , Kaneko Takeshi , Ichinose Sachiyo , Omori Akira
Published: September 2003

The developmental mechanism that contributes to the highly organized axonal connections within the cerebral cortex is not well understood. This is partly due to the lack of molecular markers specifically expressed in corticocortical associative neurons during the period of circuit formation. We have shown previously that latexin, a carboxypeptidase A inhibitor, is expressed in intrahemispheric corticocortical neurons from the second postnatal week in the rat (Arimatsu et al. [1999] Cereb. Cortex 9:569–576). In the present study, we first demonstrate in the adult rat that the orphan nuclear receptor Nurr1 is coexpressed in latexin‐expressing neurons located in layer V, sublayer VIa, and the white matter of the lateral sector of the neocortex, and also in latexin‐negative early born neurons in sublayer VIb of the entire neocortex. Virtually all Nurr1‐expressing neurons exhibit immunoreactivity for phosphate‐activated glutaminase but not for γ‐aminobutyric acid, suggesting that they are glutamatergic‐excitatory neurons. By combining Nurr1 immunohistochemistry and 5‐bromo‐2′‐deoxyuridine‐birthdating, we then show that Nurr1 is expressed in (early born) subplate neurons and (later born) presumptive latexin‐expressing neurons from embryonic day 18 onward. Finally, by combination of Nurr1 immunohistochemistry and retrograde tracing, we show that Nurr1‐expressing neurons, including those in sublayer VIb, contribute predominantly to long‐range intrahemispheric corticocortical projections. These results raise the possibility that Nurr1 plays a role in the establishment and maintenance of normal corticocortical circuitry and function. J. Comp. Neurol. 466:180–196, 2003. © 2003 Wiley‐Liss, Inc.
Estrogen‐receptor‐β distribution in the human hypothalamus: Similarities and differences with ERα distribution
Authors: Kruijver Frank P.M. , Balesar Rawien , Espila Ana M. , Unmehopa Unga A. , Swaab Dick F.
Published: September 2003

This study reports the first systematic rostrocaudal distribution of estrogen receptor beta immunoreactivity (ERβ‐ir) in the human hypothalamus and adjacent areas in five males and five females between 20–39 years of age and compares its distribution to previously reported ERα in the same patients. ERβ‐ir was generally observed more frequently in the cytoplasm than in the nucleus and appeared to be stronger in women. Basket‐like fiber stainings, suggestive for ERβ‐ir in synaptic terminals, were additionally observed in various areas. Men showed more robust nuclear ERβ‐ir than women in the medial part of the bed nucleus of the stria terminalis, paraventricular and paratenial nucleus of the thalamus, while less intense, but more nuclear, ERβ‐ir appeared to be present in, e.g., the BSTc, sexually dimorphic nucleus of the medial preoptic area, diagonal band of Broca and ventromedial nucleus. Women revealed more nuclear ERβ‐ir than men of a low to intermediate level, e.g., in the suprachiasmatic, supraoptic, paraventricular, infundibular, and medial mamillary nucleus. These data indicate potential sex differences in ERβ expression. ERβ‐ir expression patterns in subjects with abnormal hormone levels suggests that there may be sex differences in ERβ‐ir that are “activational” rather than “organizational” in nature. Similarities, differences, potential functional, and clinical implications of the observed ERα and ERβ distributions are discussed in relation to reproduction, autonomic‐function, mood, cognition, and neuroprotection in health and disease. J. Comp. Neurol. 466:251–277, 2003. © 2003 Wiley‐Liss, Inc.
Fronts in reactive convection: Bounds, stability, and instability
Authors: Constantin Peter , Kiselev Alexander , Ryzhik Lenya
Published: September 2003

This paper examines a simplified active combustion model in which the reaction influences the flow. We consider front propagation in a reactive Boussinesq system in an infinite vertical strip. Nonlinear stability of planar fronts is established for narrow domains when the Rayleigh number is not too large. Planar fronts are shown to be linearly unstable with respect to long‐wavelength perturbations if the Rayleigh number is sufficiently large. We also prove uniform bounds on the bulk burning rate and the Nusselt number in the KPP reaction case. © 2003 Wiley Periodicals, Inc.
Studies on seismic reduction of story‐incresed buildings with friction layer and energy‐dissipated devices
Authors: Li Hong‐Nan , Yin Yong‐Wei , Wang Su‐Yan
Published: September 2003

A new type of energy‐dissipated structural system for existing buildings with story‐increased frames is presented and investigated in this paper. In this system the sliding‐friction layer between the lowest increased floor of the outer frame structure and the roof of the original building is applied, and energy‐dissipated dampers are used for the connections between the columns of the outer frame and each floor of the original building. A shaking table test is performed on the model of the system and the simplified structural model of this system is given. The theory of the non‐classical damping approach is introduced to the calculation analyses and compared with test results. The results show that friction and energy‐dissipated devices are very effective in reducing the seismic response and dissipating the input energy of the model structure.

Finally, the design scheme and dynamic time‐history analyses of an existing engineering project are investigated to illustrate the application and advantages of the given method. Copyright © 2003 John Wiley & Sons, Ltd.
Seismic fragility assessment of concrete gravity dams
Authors: Tekie Paulos B. , Ellingwood Bruce R.
Published: September 2003

Many concrete gravity dams have been in service for over 50 years, and over this period important advances in the methodologies for evaluation of natural phenomena hazards have caused the design‐basis events for these dams to be revised upwards. Older existing dams may fail to meet revised safety criteria and structural rehabilitation to meet such criteria may be costly and difficult. Fragility assessment provides a tool for rational safety evaluation of existing facilities and decision‐making by using a probabilistic framework to model sources of uncertainty that may impact dam performance. This paper presents a methodology for developing fragilities of concrete gravity dams to assess their performance against seismic hazards. The methodology is illustrated using the Bluestone Dam on the New River in West Virginia, which was designed in the late 1930s. The seismic fragility assessment indicated that sliding along the dam–foundation interface is likely if the dam were to be subjected to an earthquake with a magnitude of the maximum credible earthquake (MCE) specified by the U.S. Army Corps of Engineers. Moreover, there will likely be tensile cracking at the neck of the dam at this level of seismic excitation. However, loss of control of the reservoir is unlikely. Copyright © 2003 John Wiley & Sons, Ltd.
Evaluation of predictors of non‐linear seismic demands using ‘fishbone’ models of SMRF buildings
Authors: Luco Nicolas , Mori Yasuhiro , Funahashi Yosuke , Allin Cornell C. , Nakashima Masayoshi
Published: September 2003

Predictors (or estimates) of seismic structural demands that are less computationally time‐consuming than non‐linear dynamic analysis can be useful for structural performance assessment and for design. In this paper, we evaluate the bias and precision of predictors that make use of, at most, (i) elastic modal vibration properties of the given structure, (ii) the results of a non‐linear static pushover analysis of the structure, and (iii) elastic and inelastic single‐degree‐of‐freedom time‐history analyses for the specified ground motion record. The main predictor of interest is an extension of first‐mode elastic spectral acceleration that additionally takes into account both the second‐mode contribution to (elastic) structural response and the effects of inelasticity. This predictor is evaluated with respect to non‐linear dynamic analysis results for ‘fishbone’ models of steel moment‐resisting frame (SMRF) buildings. The relatively small number of degrees of freedom for each fishbone model allows us to consider several short‐to‐long period buildings and numerous near‐ and far‐field earthquake ground motions of interest in both Japan and the U.S. Before doing so, though, we verify that estimates of the bias and precision of the predictor obtained using fishbone models are effectively equivalent to those based on typical ‘full‐frame’ models of the same buildings. Copyright © 2003 John Wiley & Sons, Ltd.
Ecosystem‐based river basin management: its approach and policy‐level application
Authors: Nakamura Takehiro
Published: September 2003

Integrated Water Resources Management is an approach aimed at achieving sustainable development with a focus on water resources. This management concept is characterized by its catchment approach, inter‐sectoral and interdisciplinary approach and multiple management objectives. There is an effort to widen the management scope to include multiple resources and environmental considerations in the river basin management schemes. In order to achieve river basin management objectives and multiple global environmental benefits, an ecosystem approach to river basin management is promoted. The Ecosystem‐based River Basin Management aims to maximize and optimize the total value of the ecosystem functions relevant to classified ecosystems within a river basin by conserving and even enhancing these functions for the next generations. A procedure to incorporate such ecosystem functions into policy framework is presented in this paper. Based on this policy framework of the Ecosystem‐based River Basin Management, a case study is introduced to apply the concept to the Yangtze River basin. According to the United Nations Environment Programme (UNEP) assessment report, this basin suffers from frequent floods of large magnitudes, which are due to the degradation of ecosystem functions in the basin. In this case, the government of the People's Republic of China introduced Ecosystem Function Conservation Areas to conserve ecosystem functions related to flood events and magnitude, such as soil conservation, agricultural practices and forestry, while producing economic benefits for the local population. Copyright © 2003 John Wiley & Sons, Ltd.
Applicability of the World Commission on Dams' recommendations for public financial institutions: a case for Japanese yen loan assistance
Authors: Fujikura Ryo , Nakayama Mikiyasu , Mori Katsuhiko
Published: September 2003

The World Commission on Dams (WCD) published ‘Dams and Development’ as its only and final report in November 2000. Identifying ‘core values’ and ‘strategic priorities’, the report proposed ‘internationally acceptable criteria and standards’. Despite the fact that the WCD itself did not intend that the report be used as a blueprint, many non‐governmental organizations strongly support the report and the criteria and guidelines recommended in the report, and demand that they be adopted in their current form by funding organizations. The WCD criteria and guidelines were found to have several ‘methodological’ problems, and it appears impossible to apply the recommended criteria and guidelines as they stand. This study examines the applicability of the WCD criteria and guidelines for public financing institutes involved in overseas development assistance and proposes necessary measures to increase their applicability in order to realize core values and strategic priorities. The character of and relationships among key decision points, strategic priorities, criteria, and guidelines should be clarified. Then, this study examines the applicability of the WCD recommendations for Japanese public financial institutions, as Japan has nearly become the sole bilateral donor providing financial assistance (loans) for large dam construction projects. The public financial institution can only be mandated to check the legal status of the decisions made regarding Stages 1 and 2 which are the first two of the five successive stages from the planning to the operation of the dam project. Needs assessment and alternative selection are expected to be conducted at Stage 1 and 2 respectively. The Japan Bank for International Cooperation (JBIC), which deals with the Japanese concessional yen loan, and the Japan International Cooperation Agency (JICA), which is in charge of technical assistance, are featured in this study. As for the Japanese concessional yen loan assistance, there are other inherent problems for adopting the recommendations. First, it is not clear which government agency officially and substantially carries the decision‐making responsibility. Second, JBIC may be involved only when Stage 2 has been completed, and it should be decided and clarified to what extent the Japanese government, as well as JIBC and JICA, should be involved in Stages 1 and 2 (2A: intensive studies on alternatives) of a project for which funding is requested. These issues need to be solved if the Japanese government wishes to adopt the recommendations. Copyright © 2003 John Wiley & Sons, Ltd.
Chemistry of stream water in a snowy temperate catchment
Authors: Suzuki Keisuke
Published: September 2003

The seasonal variation of the quality of stream water in a snowy temperate area, where rain or temporary warming can cause frequent melting at the surface of snow cover, even in mid‐winter, was studied. Monthly runoff is highest in the snowmelt seasons March and April, and lowest in November. Since floods in the rainy season or in the autumn rainy period take place irregularly, they contribute little to monthly runoff. In winter, as with the snowmelt season, the proportion of HCO3− in stream water is relatively low, while the proportions of Cl−, NO3− and SO42− are relatively high. In mid‐winter and during the snowmelt season, the amount of each ion clearly indicates that stream water quality is strongly influenced by snow meltwater. Copyright © 2003 John Wiley & Sons, Ltd.
Development of a distributed hydrological model and its application to soil erosion simulation in a forested catchment during storm period
Authors: Su Baolin , Kazama So , Lu Minjiao , Sawamoto Masaki
Published: September 2003

A spatially distributed Xinanjiang model (DXAJ) has been developed to simulate the hourly hydrological process of a storm event caused by Typhoon No. 11 during the period of the 22–23 August 2001 in the Kamafusa Lake catchment, Miyagi Prefecture, Japan. The catchment is divided into 50 × 50 m2grid cells, and the runoff generation component of the Xinanjiang rainfall‐runoff model is applied to each grid cell. An optimal routing order approach is used to implement the distributed routing, i.e. the runoff generated in each grid cell is routed together with upstream inflow from upstream grid cells to downstream grid cells according to the optimal routing order, which is derived from a simulated stream network. One process‐based soil erosion model is coupled onto this distributed hydrological model to simulate suspended solids generation in each grid cell and generated suspended solids are routed together with runoff from upstream grid cells to downstream grid cells. The simulation results are in good agreement with the observed hydrograph and pollutograph. The soil erosion simulation was improved through the consideration of rainfall intensity in the soil erosion model. Copyright © 2003 John Wiley & Sons, Ltd.
Recession flow analysis of the Blue Nile River
Authors: Mishra Anil , Hata Takeshi , Abdelhadi A. W. , Tada Akio , Tanakamaru Haruya
Published: September 2003

Estimates of the amount of recession flow can be derived from streamflow records. Such estimates are critical in the assessment of low flow characteristics for the Blue Nile River, from which about two‐thirds of the irrigation requirements in Sudan are satisfied. The recession flow hydrograph can be estimated by fitting the conceptual non‐linear storage outflow model using an iterative algorithm. An analytical model to forecast the Blue Nile recession flow is developed and the performance of the model is compared to the previous Blue Nile recession flow model. In the proposed model, a simple linear regression equation is introduced to illustrate the effect of antecedent flow on the recession parameter. Results indicate that the model can provide a simple and reliable method to predict the recession flow of the Blue Nile River. Copyright © 2003 John Wiley & Sons, Ltd.
Statistical analyses on the effects of air temperature fluctuations on river water qualities
Authors: Ozaki Noriatsu , Fukushima Takehiko , Harasawa Hideo , Kojiri Toshiharu , Kawashima Katsunori , Ono Miyuki
Published: September 2003

In order to gain an insight into the effects of air temperature on river water quality, data were statistically analysed using meteorological and river water quality data. Two types of data set were used for river water temperature. One type involved five sampling points within different rivers where water temperature data were obtained daily, and the other involved 82 sampling points located within 27 rivers where water temperature and other water quality data were obtained monthly. Influential factors for different time scales were investigated. From the analyses, the gradient of water temperature to air temperature considered on a daily scale was 0·1–0·5 °C °C−1 and was influenced by the hydrological scale of the river basin. The gradient observed using an annual scale was 0·5–1·5 °C °C−1 and was supposed to be influenced by solar radiation. Under the condition that solar radiation is constant, the gradient on an annual scale was predicted to be less than unity (0·5–0·85 °C °C−1). As for the other indices, from the analysis on an annual scale, an increase in air temperature resulted in an increase in biological oxygen demand and suspended solids, and a decrease in dissolved oxygen in almost all rivers. Based on the results, it was suggested that global warming has a deteriorating effect on river water quality. Copyright © 2003 John Wiley & Sons, Ltd.