bluuebunny/crossref_metadata_2025 huggingface dataset:
Pneumococcal Interaction with Human Dendritic Cells: Phagocytosis, Survival, and Induced Adaptive Immune Response Are Manipulated by PavA
Authors: Noske Nadja , Kämmerer Ulrike , Rohde Manfred , Hammerschmidt Sven
Published: July 2009

Dendritic cells (DCs) ingest and process bacteria for presenting their Ags to T cells. PavA (pneumococcal adherence and virulence factor A) is a key virulence determinant of pneumococci under in vivo conditions and was shown to modulate adherence of pneumococci to a variety of nonprofessional phagocytic host cells. Here, we demonstrated the role of PavA for the interaction of human DCs with live pneumococci and analyzed the induced host cell responses upon ingestion of viable pneumococci. Expression of PavA protected pneumococci against recognition and actin cytoskeleton-dependent phagocytosis by DCs compared with isogenic pavA mutants. A major proportion of internalized pneumococci were found in membrane-bound phagosomes. Pneumococcal phagocytosis promotes maturation of DCs, and both wild-type pneumococci and PavA-deficient pneumococci triggered production of proinflammatory cytokines such as IL-1β, IL-6, IL-8, IL-12, and TNF-α and antiinflammatory IL-10. However, cytokine production was delayed and reduced when DCs encounter pneumococci lacking PavA, which also results in a less efficient activation of the adaptive immune response. Strikingly, purified PavA reassociates to pneumococci but not DCs and reduced phagocytosis of the pavA mutant to levels similar to those of wild-type pneumococci. Additionally, pavA mutants covered with exogenously provided PavA protein induced a DC cytokine profile similar to wild-type pneumococci. In conclusion, these results suggest that PavA is key factor for live pneumococci to escape phagocytosis and to induce optimal cytokine productions by DCs and adaptive immune responses as well.
Parameters Underlying Distinct T Cell-Dependent Polysaccharide-Specific IgG Responses to an Intact Gram-Positive Bacterium versus a Soluble Conjugate Vaccine
Authors: Colino Jesus , Chattopadhyay Gouri , Sen Goutam , Chen Quanyi , Lees Andrew , Canaday David H. , Rubtsov Anatoly , Torres Raul , Snapper Clifford M.
Published: July 2009

IgG anti-polysaccharide (PS) responses to both intact Streptococcus pneumoniae (Pn) and PS conjugate vaccines are dependent on CD4+ T cells, B7-dependent costimulation, and CD40-CD40-ligand interactions. Nevertheless, the former response, in contrast to the latter, is mediated by an ICOS-independent, apoptosis-prone, extrafollicular pathway that fails to generate PS-specific memory. We show that pre-existing PS-specific Igs, the bacterial surface or particulation, selective recruitment of B cell subsets, or activation and recruitment of Pn protein-specific CD4+ T cells do not account for the failure of Pn to generate PS-specific IgG memory. Rather, the data suggest that the critical factor may be the lack of covalent attachment of PS to protein in intact Pn, highlighting the potential importance of the physicochemical relationship of PS capsule with the underlying bacterial structure for in vivo induction of PS-specific Igs.
Esculetin Restores Mitochondrial Dysfunction and Reduces Allergic Asthma Features in Experimental Murine Model
Authors: Mabalirajan Ulaganathan , Dinda Amit Kumar , Sharma Surendra Kumar , Ghosh Balaram
Published: July 2009

We recently showed that IL-4-dependent oxidative stress and mitochondrial dysfunction are associated with allergic asthma. IL-4 also induces a prooxidant enzyme, 15-lipoxygenase, which predominantly expresses in asthmatic bronchial epithelium and degrades mitochondria. Esculetin (6,7-dihydroxy-2H-1-benzopyran-2-one), a plant-derived coumarin and immunomodulator, was found to have potent bronchodilating property in carbachol-induced bronchoconstriction and also reduces mitochondrial dysfunction in neurological diseases. In this study, we evaluated its potential in restoring mitochondrial dysfunction and structural changes and anti-asthma property in a mouse model of experimental asthma. In this study, we found that esculetin treatment reduced airway hyperresponsiveness, Th2 response, lung eotaxin, bronchoalveolar lavage fluid eosinophilia, airway inflammation, and OVA-specific IgE. It also reduced the expression and metabolites of 15-lipoxygenase and lipid peroxidation which is an essential prerequisite for mitochondrial dysfunction. Interestingly, esculetin treatment restored the activity of cytochrome c oxidase of electron transport chain in lung mitochondria and expression of the third subunit of cytochrome c oxidase of electron transport chain in bronchial epithelium. It reduced the cytochrome c level and caspase 9 activity in lung cytosol and restored mitochondrial structural changes and lung ATP levels. In addition, esculetin reduced subepithelial fibrosis and TGF-β1 levels in the lung. These results suggest that esculetin not only restores mitochondrial dysfunction and structural changes but also alleviates asthmatic features.
Cutting Edge: NF-κB Activating Pattern Recognition and Cytokine Receptors License NLRP3 Inflammasome Activation by Regulating NLRP3 Expression
Authors: Bauernfeind Franz G. , Horvath Gabor , Stutz Andrea , Alnemri Emad S. , MacDonald Kelly , Speert David , Fernandes-Alnemri Teresa , Wu Jianghong , Monks Brian G. , Fitzgerald Katherine A. , Hornung Veit , Latz Eicke
Published: July 2009

The IL-1 family cytokines are regulated on transcriptional and posttranscriptional levels. Pattern recognition and cytokine receptors control pro-IL-1β transcription whereas inflammasomes regulate the proteolytic processing of pro-IL-1β. The NLRP3 inflammasome, however, assembles in response to extracellular ATP, pore-forming toxins, or crystals only in the presence of proinflammatory stimuli. How the activation of gene transcription by signaling receptors enables NLRP3 activation remains elusive and controversial. In this study, we show that cell priming through multiple signaling receptors induces NLRP3 expression, which we identified to be a critical checkpoint for NLRP3 activation. Signals provided by NF-κB activators are necessary but not sufficient for NLRP3 activation, and a second stimulus such as ATP or crystal-induced damage is required for NLRP3 activation.
Hamartia: Foucault and Iran 1978–1979 (2: Scholarship and significance)
Authors: Beukes Johann
Published: July 2009

Against the backdrop of the introduction and analysis of Foucault’s Iran writings in the first of two articles, this second article attempts to contribute to an understanding of Foucault’s involvement in the revolution in Iran (1978–1979) by 1) employing the concluding suggestions in the first article as premises for 2) an analysis of three explicit contributions (Janet Afary and Kevin Anderson, Ian Almond, and Danny Postel) that have been made recently on this traditionally neglected issue in Foucault scholarship, 3) and, via the notion of an ‘ethics of Self-discomfort’, arguing for an acknowledgement of the philosophical significance of Foucault’s involvement in Iran and his writings from that period.
Magnetic and Structural Investigation of ZnSe Semiconductor Nanoparticles Doped With Isolated and Core‐Concentrated Mn2+ Ions
Authors: Graf Christina , Hofmann Andreas , Ackermann Thomas , Boeglin Christine , Viswanatha Ranjani , Peng Xiaogong , Rodríguez Arantxa Fraile , Nolting Frithjof , Rühl Eckart
Published: June 2009

X‐Ray magnetic circular dichroism (XMCD) experiments on diluted magnetic semiconductor nanocrystals (2–7 nm) are reported in order to study their local electronic structure and magnetic properties. ZnSe nanoparticles containing either single manganese ions (Mn2+) distributed in the lattice of the entire particle or a MnSe core in the center are prepared using high temperature approaches. The Mn2+ concentration is varied between less than one to several tens of manganese ions per nanocrystal. For all samples it is shown that the Mn2+ is exclusively present in the bulk of ZnSe nanoparticles with no evidence for oxidation to higher Mn‐oxidation states. The magnetic ions are highly polarized inside the nanocrystals reaching about 80% of the theoretical value of a pure d5 state under identical conditions for the case of isolated manganese ions. Nanocrystals with a MnSe core ZnSe shell structure reach <50% of this value. Thus, their polarization is significantly more hindered, which is due to the significantly enhanced Mn–Mn interactions and a more distorted crystalline lattice. In contrast, no coupling between the manganese centers is observed in the nanoparticles doped samples with low concentrations of Mn2+, indicating that these ions are isolated in the bulk of the nanoparticles.
Towards Continuous Flow, Highly Enantioselective Allylic Amination: Ligand Design, Optimization and Supporting
Authors: Popa Dana , Marcos Rocío , Sayalero Sonia , Vidal‐Ferran Anton , Pericàs Miquel A.
Published: June 2009

A family of enantiopure diphenylphosphinooxazolines (PHOX) containing in their structures a sterically tunable alkoxymethyl group (‐CH2OR) has been optimized for the palladium‐catalyzed asymmetric allylic amination. The optimal catalyst (R=CH3), depicting very high catalytic activity and broad scope applicability, has been further modified to include an ω‐alkynyloxy substituent of variable length for polymer supporting via click chemistry, and has been anchored onto slightly cross‐linked azidomethyl poly(styrene). The length of a polymethylene chain connecting the PHOX unit with the 1,2,3‐triazole linker has been optimized, and the first polymer‐supported PHOX ligands for the highly enantioselective allylic amination have been prepared in this manner. Conditions for catalyst recovery and reuse in microwave‐promoted amination reactions have been established, and the system has been finally adapted to continuous flow operation.
Exploring the Biocatalytic Scope of Alditol Oxidase from Streptomyces coelicolor
Authors: van Hellemond Erik W. , Vermote Linda , Koolen Wilma , Sonke Theo , Zandvoort Ellen , Heuts Dominic P. H. M. , Janssen Dick B. , Fraaije Marco W.
Published: June 2009

The substrate scope of the flavoprotein alditol oxidase (AldO) from Streptomyces coelicolor A3(2), recombinantly produced in Escherichia coli, was explored. While it has been established that AldO efficiently oxidizes alditols to D‐aldoses, this study revealed that the enzyme is also active with a broad range of aliphatic and aromatic alcohols. Alcohols containing hydroxy groups at the C‐1 and C‐2 positions like 1,2,4‐butanetriol (Km=170 mM, kcat=4.4 s−1), 1,2‐pentanediol (Km=52 mM, kcat=0.85 s−1) and 1,2‐hexanediol (Km=97 mM, kcat=2.0 s−1) were readily accepted by AldO. Furthermore, the enzyme was highly enantioselective for the oxidation of 1,2‐diols [e.g., for 1‐phenyl‐1,2‐ethanediol the (R)‐enantiomer was preferred with an E‐value of 74]. For several diols the oxidation products were determined by GC‐MS and NMR. Interestingly, for all tested 1,2‐diols the products were found to be the α‐hydroxy acids instead of the expected α‐hydroxy aldehydes. Incubation of (R)‐1‐phenyl‐1,2‐ethanediol with 18O‐labelled water (H218O) revealed that a second enzymatic oxidation step occurs via the hydrate product intermediate. The relaxed substrate specificity, excellent enantioselectivity, and independence of coenzymes make AldO an attractive enzyme for the preparation of optically pure 1,2‐diols and α‐hydroxy acids.
Impact of Neuritin 1 (NRN1) polymorphisms on fluid intelligence in schizophrenia
Authors: Chandler David , Dragović Milan , Cooper Matthew , Badcock Johanna C. , Mullin Benjamin H. , Faulkner Deb , Wilson Scott G. , Hallmayer Joachim , Howell Sarah , Rock Daniel , Palmer Lyle J. , Kalaydjieva Luba , Jablensky Assen
Published: June 2009

Neuritin 1 (NRN1), an activity‐regulated gene with multiple roles in neurodevelopment and synaptic plasticity, is located within the 6p24‐p25 interval on chromosome 6, previously identified as linked to a subtype of schizophrenia (SZ) characterized by pervasive cognitive deficit (CD). We have tested the effect of NRN1 sequence variation on susceptibility to SZ and on general cognitive ability in patients and non‐psychiatric control subjects by re‐sequencing the coding regions of NRN1 and its flanking sequences, and genotyping 19 single‐nucleotide polymorphisms (SNPs) in 336 SZ patients and 172 healthy control individuals. All participants completed comprehensive neurocognitive assessment, including tests estimating premorbid/prior IQ and current IQ. Logistic regression analyses found no significant association for any of the 19 SNPs with SZ or its CD subtype. However, linear regression analysis gave significant association (P = 0.024 and P = 0.027 after correction for multiple testing) for polymorphisms rs1475157 and rs9405890 with current IQ in the patient group. In SZ, the rs1475157–rs9405890 haplotypes revealed a highly significant association with the abstraction component of current (“fluid”) intelligence (P = 0.0014), and with percentage loss of IQ points between premorbid and current intelligence (P = 0.0041). Results in the control group were not significant after correction. This is the first analysis of association between variation in NRN1 and SZ. The findings suggest a role of NRN1 as a modifier of cognitive functioning in SZ, with implications for future research into the impact of the environment on the development and maintenance of “fluid” intelligence. © 2009 Wiley‐Liss, Inc.
A screen of SLC1A1 for OCD‐related alleles
Authors: Wang Y. , Adamczyk A. , Shugart Y.Y. , Samuels J.F. , Grados M.A. , Greenberg B.D. , Knowles J.A. , McCracken J.T. , Rauch S.L. , Murphy D.L. , Rasmussen S.A. , Cullen B. , Pinto A. , Fyer A.J. , Piacentini J. , Pauls D.L. , Bienvenu O.J. , Riddle M. , Liang K.Y. , Valle D. , Wang T. , Nestadt G.
Published: June 2009

SLC1A1, which encodes the neuronal and epithelial glutamate transporter, is a promising candidate gene for obsessive‐compulsive disorder (OCD). In this study, we conducted capillary electrophoresis single‐strand conformation polymorphism (CE‐SSCP) screen for all 12 identified exons, including all coding regions and ∼50 bp of flanking introns of the human SLC1A1 in 378 OCD‐affected individuals. Full sequencing was completed on samples that showed an aberrant SSCP tracing for identification of the underlying sequence variants. Our aim was to determine if there are differences in the frequencies of relatively common alleles, or rare functional alleles, in 378 OCD cases and 281 ethnically matched controls. We identified one nonsynonymous coding SNP (c.490A > G, T164A) and three synonymous coding SNP (c.81G > C, A27A; c.414A > G, T138T; c.1110T > C, T370T) in case samples. We found no statistical differences in genotype and allele frequencies of common cSNPs in SLC1A1 between the OCD cases and controls. The rare variant T164A was found only in one family. Further investigation of this variant is necessary to determine whether and how it is related to OCD. There was no other evidence of significant accumulation of deleterious coding mutations in SLC1A1 in the OCD cases. © 2009 Wiley‐Liss, Inc.
Effect of CaO on NH3 + NO + O2 reaction system in the absence and presence of high concentration CO2
Authors: Li Tianjin , Zhuo Yuqun , Chen Changhe , Xu Xuchang
Published: June 2009

The effect of CaO on the NH3 + NO + O2 reaction system at 650–850 °C was investigated. High CO2 concentration was added to investigate the effect of CaCO3 on this reaction system also. Experimental results showed that CaO had a strong catalytic effect on NH3 decomposition, NH3 oxidation by O2 to NO, and NO reduction by NH3 in the absence of O2. The overall effect of CaO on the NO + NH3 + O2 reaction was to enhance NH3 oxidation by O2 to produce more NO. A small amount of NO2 and no N2O was detected in the outlet gas stream over CaO in the NH3 + NO + O2 reaction. NO2 formation decreased with temperature increase. NO2 formation in the NH3 + NO + O2 reaction over CaO was attributed to the oxidization of NH3 and NO by O2. The performance of CaCO3 was different from CaO. NH3 decomposition was promoted, but NH3 oxidation to NO was inhibited after CaO was converted to CaCO3. No catalytic activity for NO reduction was detected in NO + NH3 reaction over CaCO3, but strong activity for NH3 decomposition was observed. NO and NH3 outlet concentration over CaCO3 in the NH3 + NO + O2 reaction was lower and higher, respectively, than that of CaO, which was mainly due to the difference of CaO and CaCO3 for NH3 oxidation. NO2 formation was inhibited, but N2O was observed over CaCO3. N2O formation increased with temperature increase at 650–750 °C, and then decreased at 750–850 °C. Copyright © 2009 Curtin University of Technology and John Wiley & Sons, Ltd.
Study on flow patterns in different types of direct coal liquefaction reactors
Authors: Ren Xiangkun , Fang Dingye , Jin Jialu , Gao Jinsheng
Published: June 2009

Hot mold flow patterns in bubble reactor, ebullated reactor and loop reactor have been researched and compared in hydrogen–oil system and hydrogen–oil coal slurry system of direct coal liquefaction (DCL) pilot plant under high temperature and high pressure. The results demonstrate that the ebullated reactor and loop reactor (on the condition of optimum recycle ratio) show good performance of back‐mixing, which can not only reduce temperature differences between top and bottom in the reactor, but also avoid big solid particles deposition that easily occurs during liquefaction process. The ebullated reactor used in the first demonstration plant has good performance. Copyright © 2009 Curtin University of Technology and John Wiley & Sons, Ltd.
Hydrogenation of naphthalene on nickel phosphide supported on silica
Authors: Zhang Xiaofei , Zhang Qiumin , Guan Jun , He Demin , Hu Haoquan , Liang Changhai
Published: June 2009

Two series of silica supported nickel phosphide catalysts with different Ni/P atomic ratios of the precursors and loadings had been prepared by a temperature‐programmed reduction of nickel phosphate. The resulting samples were characterized by means of N2 physorption and X‐ray diffraction (XRD). The activities of the catalysts were measured for naphthalene hydrogenation (HYD) at 340 °C and 4 MPa. The operating conditions of naphthalene HYD such as temperature, pressure and H2/liquor ratio were tested in detail. It is found that all the samples were active in this reaction and the sample which precursor with Ni/P = 1.25 and loading with 30 wt% displayed the highest catalytic activity and decalin selectivity. Naphthalene conversion and selectivity to decalin went through a maximum (100% and 83% at 340 °C) with the increasing reaction temperature. Copyright © 2009 Curtin University of Technology and John Wiley & Sons, Ltd.
A novel route for well‐defined polystyrene‐grafted multiwalled carbon nanotubes via the radical coupling reaction
Authors: Sui Kunyan , Yang Chunjia , Gao Song , Shan Xin , Xia Yanzhi , Zheng Qiang
Published: June 2009

Multiwalled carbon nanotubes‐graft‐polystyrene (MWNTs‐g‐PS) was synthesized by atom transfer nitroxide radical coupling chemistry. MWNTs with 2,2,6,6‐tetramethylpiperidine‐1‐oxy (MWNTs‐TEMPO) groups was prepared first by esterification of 4‐hydroxy (HO)‐TEMPO and carboxylic acid group on the surface of MWNTs (MWNTs‐COOH); PS with bromide end group (PS‐Br) were then obtained by atom transfer radical polymerization using ethyl 2‐bromoisobutyrate as initiator and CuBr/N,N,N′,N″,N″‐pentamethyldiethylenetriamine as catalyst. The MWNTs‐TEMPO was mixed with PS‐Br and heated to 90°C in the presence of CuBr/PMDETA to form MWNTs‐g‐PS. The product was characterized by FTIR, NMR, TGA, and TEM. TEM indicates that the MWNTs are enveloped by the polymer molecules. The content of grafted polymers is 46.7% by TGA measurements when the number‐average molecular weight (Mn) of PS‐Br is 10,200 g/mol. The as‐prepared nanocomposites exhibit relatively good dispersibility in solvents such as CH2Cl2, THF, and toluene. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Analysis of the influence of glycidyl methacrylate on molecular weight and refractive index in styrene‐methylmethacrylate‐glycidyl methacrylate copolymers through mixture design of experiments
Authors: Cerna Jorge R. , Alejandro Ana S. , Matla Maria
Published: June 2009

To analyze the influence of the percentage of glycidyl methacrylate (GMA) coupled with polymeric chains to determine their effect on molecular weight (Mw) and refractive index (nD), a Mixture Design of Experiments (MDOE) has been used. A “d” optimal mixture design for four components was used for planning the runs and analyzing the information using statistical tools. The prototypes generated were synthesized using styrene (St) 73–89.98%, methylmethacrylate (MMA) 8–22%, and glydicyl methacrylate (GMA) 2–10% at different ratios according to the experiment design. In this sense, the prototypes are terpolymers (St‐MMA‐GMA). According to the desired properties of the prototypes reviewed in literature and market studies, this is expressed in materials with a preferred nD (ca. 1.5750–1.5894) and molecular weight (ca. 300,000 g/mol) the ratios were established. In a radical polymerization process using a commercial initiator (Trigonox 22E‐50) and a temperature program (120–200°C) simulating an industrial process, the polymerization reactions were conducted. The detailed information derived from DOE here is presented. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Flexural properties of sawdust reinforced phenolic composites: Pilot study
Authors: Ku Harry Siu‐Lung , Cardona Franciso , Trada Mohar , Vigier Gurlaume
Published: June 2009

The advantageous properties of sawdust and phenolic resins were combined by making sawdust reinforced phenolic composites with different percentages by weight of sawdust. The sawdust was divided into three grades in accordance with its particulate size. Garamite and propylene glycol were added individually and together to enhance the flexural properties of the composites obtained. Without any garamite and propylene glycol, it was discovered that the best flexural properties of the composites were obtained when the percentage by weight of sawdust (<300 μm) is up to 15%. Beyond this, the flexural properties dropped significantly; in addition, the fluidity of the composite was very low and the mixture was not suitable for casting. In general, the flexural modulus of the composites decreases with an increase in sawdust content, i.e., they are more elastic but their maximum flexural strain does not improve. Garamite was therefore added to improve the maximum flexural strains of the composites and this was successful. The addition of propylene glycol makes the composite more plastic. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Conversion and shrinkage analysis of acrylated hyperbranched polymer nanocomposites
Authors: Geiser Valérie , Leterrier Yves , Månson Jan‐Anders E.
Published: June 2009

The photo‐curing behavior of composites containing nanosized SiO2 in an acrylated hyperbranched polymer matrix was investigated by means of photo differential scanning calorimetry. The chemical conversion data were analyzed using an autocatalytic model, paying close attention to the influence of composition and UV intensity. It was shown that the reaction order and the autocatalytic exponent were independent of UV intensity and filler fraction, whereas the rate constant showed strong intensity dependence, but weak filler dependence. Maximum conversion was independent of UV intensity, but was reduced when a filler was present. The dispersion state influenced the gel‐point of the composites, but had no influence on the overall cure kinetics. Cure shrinkage reduction of ∼ 33% could be achieved by adding 20 vol% of filler. This was attributed to the reduced double bond conversion of the matrix due to the presence of the filler. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Curing behavior and thermal properties of trifunctional epoxy resin cured by 4,4′‐diaminodiphenylmethane
Authors: Jue Cheng , Juan Li , Wantai Yang
Published: June 2009

A novel trifunctional epoxy resin (TMBPBTH‐EPOXY) was synthesized in our laboratory, and its curing behavior and performance were studied by curing with 4,4′‐diaminodiphenylmethane (DDM) with the mass ratio of 30 : 100 of TMBPBTH‐EPOXY and DDM. The mixtures of TMBPBTH‐EPOXY/DDM were cured at 100, 140, and 160°C, respectively. The curing state was kept for different time from 1 to 6 h. The transition reaction of epoxide group during curing process was monitored by Fourier transform infrared spectroscopy. It was found that curing reaction was both dependent on the curing temperature and curing time, and the curing temperature has more effect on the curing reaction than the curing time. The curing activation energy was investigated by differential scanning calorimetry to be 55.13 and 55.10 kJ/mol. The glass transition temperature of TMBPBTH‐EPOXY/DDM system was 240.2°C. The thermal decomposition temperature at different temperatures and time were studied by thermogravimetric analyzer. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Structural, electrical, and electromagnetic properties of cotton fabrics coated with polyaniline and polypyrrole
Authors: Onar Nurhan , Akşit Aysun Cireli , Ebeoglugil M. Faruk , Birlik Isil , Celik Erdal , Ozdemir Ismail
Published: June 2009

In this study, the structural, electrical, and electromagnetic properties of cotton fabrics coated with polyaniline (PAni) and polypyrrole (PPy) were investigated and compared. For the aims, anilin and pyrrole were used as monomers, andin situpolymerization on cotton fabric by chemical oxidative polymerization was performed. After production, the structural properties of the fabrics were determined with Fourier transform infrared spectroscopy and X‐ray diffraction. In addition, ultraviolet (UV) permeability, tensile strength, colorfastness, and electrical and electromagnetic measurements of the fabric samples were carried out. The resistance values of the cotton fabrics coated with PAni and PPy were found to be 350 and 512 Ω, respectively. The average electromagnetic shielding efficiency and average absorption values of the cotton fabrics coated with PAni were determined to be 3.8 dB and 48%, respectively, and these values for the cotton fabrics coated with PPy were 6 dB and 50%, respectively. Consequently, a significant difference was not observed between the resistance values and electromagnetic parameters of the fabrics coated with PAni and PPy, although the intact textile characteristics of the fabric coated with PPy were protected and improved, whereas the characteristics of the fabric coated with PAni were inferior. Moreover, we first report that the fabrics coated with conductive polymers had excellent UV‐protection properties. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Morphology and particle size of nanograde polyurethane/polyacrylate hybrid emulsions
Authors: Chai Shu Ling , Jin Martin Ming
Published: June 2009

Poly(urethane acrylate) (PUA) composite particles were prepared by seeded surfactant‐free emulsion polymerization. The aqueous polyurethane (PU) dispersions were used as seed particles. The diameters of the seed particles of the aqueous PU dispersions and PUA composite latexes were measured by dynamic light scattering. The microstructures of the PUA composite emulsion particles were observed by transmission electron microscopy. The influences of the amount of the hydrophilic chain extender, the types of initiators, and the PU/polyacrylate (PA) weight ratios on the diameters of the aqueous PU and composite emulsions were also studied. The results showed that the PUA composite emulsions formed a core–shell structure with PU as the shell and with PA as the core. The diameter of the PU seed particles and the particle size of the PUA composite emulsions greatly depended on the amounts of the hydrophilic chain extender used in the preparation of the PU seed; when the hydrophilic chain extender concentration was 7.4%, the average diameter of the PUA composite emulsion particles showed the minimum value. The types of initiators and PU/PA weight ratios did not have a significant influence on the diameter of the PUA composite latex particles. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Environment‐friendly synthesis of long chain semiaromatic polyamides with high heat resistance
Authors: Wang Wenzhi , Wang Xianwen , Li Ruixue , Liu Baoyu , Wang Ergang , Zhang Yonghua
Published: June 2009

Long chain semiaromatic polyamides have been synthesized by the reactions of terephthalic acid with long chain aliphatic diamines, and characterized by infrared spectrum, nuclear magnetic resonance and elemental analysis. The thermal behaviors were studied by differential scanning calorimetry analysis and thermogravimetric analysis. The resultant polyamides have intrinsic viscosity ranging from 1.75 to 1.93 dLg−1. The solubility, dynamic mechanical and mechanical properties of the polyamides have also been investigated. The mechanical properties and heat resistance of long chain semiaromatic polyamides were compared with those of PA9T. PA10T has the advantages of low cost and preparation from environmental friendly solvents and possesses the similar mechanical properties and heat resistance compared to PA9T. The long chain semiaromatic polyamides are a class of promising, heat‐resisting and processability engineering plastics. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Synthesis, morphology, and melting behavior of poly(ether ether ketone) of different molecular weights
Authors: Lu Qianshu , Yang Zhenguo , Li Xiaohui , Jin Shilei
Published: June 2009

To investigate how the molecular weight of poly(ether ether ketone) affected the crystallization behavior, the nucleophilic reaction synthetic technology was used to obtain poly(ether ether ketone) of different molecular weights and the trend of the molecular weight varying with the duration of the reaction. Furthermore, the influence molecular weight has brought to the morphology and the melting behavior was investigated by means of FTIR, OM, WAXD, and DSC and thoroughly discussed in theory. Results showed that with the increase of the molecular weight, the degree of crystalline perfection and the lamellar thickness descended as well as the radius of spherulite diminished due to the difficulty of the chain mobility. Moreover, the melting temperature mounted up at first then decreased with the growing of the molecular weight indicating how the lamellar thickness and the melting heat per unit volume affected the melting behavior together. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Porous structure and thermal stability of photosensitive silica/polyimide composites prepared by sol‐gel process
Authors: Huang Shu‐Hui , Don Trong‐Ming , Lai Wei‐Chi , Chen Ching‐Chung , Cheng Liao‐Ping
Published: June 2009

The sol‐gel method was employed to synthesize an inorganic–organic photosensitive composite material, silica/polyimide. Silica was covalently bonded to polyimide by introduction of 1,4‐aminophenol as a coupling agent. A photosensitive cross‐linking agent, 2‐(dimethylamino) ethyl methacrylate, was used to engender UV sensitivity to the composite. Using field emission scanning electron microscope imaging at very high magnifications, the composite film was found to exhibit a porous cross‐sectional structure. The pores were interconnected to form numerous continuous channels within the matrix and silica particles were attached to the pore wall of the polyimide host. Depending on the preparation conditions, the size of the silica particles could vary from 20 nm to a few μm. The thermal degradation temperatures, dynamic mechanical properties, glass transition temperatures, thermal expansion coefficients, and dielectric constants of various silica/polyimide composites were measured, and the results indicated that incorporation of silica could improve the thermal and dimensional stabilities of the polyimide. Also, because the silica/polyimide composite had a porous interior structure, it had a rather low dielectric constant with the lowest achievable value being 1.82. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
A kinetic study of the thermal degradation of chitosan‐metal complexes
Authors: Taboada Edelio , Cabrera Gustavo , Jimenez Romel , Cardenas Galo
Published: June 2009

The thermal degradation of metal complexes formed by chitosan with Cu(II), Ni(II), Co(II), and Hg(II), at different metal concentrations, was studied by thermogravimetric analysis in a nitrogen atmosphere over the temperature range 25–800°C. The results indicate that thermal degradation of chitosan and chitosan‐metal ion complexes could be of one or two‐stage reaction. In the thermal degradation of chitosan with metal complexes, the temperature of initial weight loss and the temperature of maximum weight loss rate decrease. Fourier transform infrared spectroscopy was used to probe the interaction of chitosan with metal ions. The bands of NH, CO, COC groups of chitosan are shifted or change their intensity in the presence of metal. These changes in the characteristic bands are taken as evidence of the influence of metal ions on the thermal stability of chitosan. Broido's method was employed to evaluate the activation energies as a function of the degree of degradation. The presence of metal ions provoked a decrease in the thermal stability of chitosan, which became more marked when the concentration of metal was increased. The dynamic study showed that the apparent activation energy values of the main stage of the thermal degradation of chitosan‐metal complexes decrease as the strength of the polymer‐metal interaction increases. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Preparation and characterization of zein and zein/poly‐L‐lactide nanofiber yarns
Authors: Yao Chen , Li Xinsong , Song Tangying
Published: June 2009

Zein and zein/poly‐L‐lactide (PLLA) nanofiber yarns were prepared by conjugate electrospinning using coupled spinnerets applied with two high electrical voltages of opposite polarities in this article. Structure and morphology of zein yarns were investigated by SEM and X‐ray diffraction. The results showed that zein yarn consisted of large quantity of fibers with diameters ranging from several hundreds nanometers to a few microns, and zein concentration played a significant role on the diameter of nanofibers in yarns. To improve mechanical property of nanofiber yarns, PLLA was then incorporated with zein. Zein/PLLA composite nanofiber yarns conjugate electrospun from solution with concentration of 7.5% (zein, w/v)/7.5% (PLLA, w/v) exhibited tensile strength of 0.305 ± 0.014 cN/dtex. The composite yarns showed better nanofiber alignment along the longitudinal axis. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
ATP‐fueled soft gel machine with well‐oriented structure constructed using actin‐myosin system
Authors: Shikinaka Kazuhiro , Takaoka Shintaro , Kakugo Akira , Osada Yoshihito , Gong Jian Ping
Published: June 2009

Fibrous actomyosin gel was obtained by applying an external shear stress to actomyosin solution injected from a syringe and then performing chemical cross‐linking. The actomyosin gel shrunk when ATP was added, and the shrinkage ratio was proportional to its ATPase activity. The shrinkage of the gel was repeatable at least for four times. Furthermore, the shrinkage of the gel enhanced the regular orientation of the actin and myosin filaments in the gel, which in turn enhanced the shrinking velocity of the gel. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Using patterns of reef fish assemblages to refine a Habitat Classification System for marine parks in NSW, Australia
Authors: Malcolm Hamish A. , Smith Stephen D. A. , Jordan Alan
Published: June 2009

The Solitary Islands Marine Park (SIMP) in New South Wales (NSW), Australia, is located in a tropical‐temperate biotone, with variable influence of the tropical East Australian Current (EAC) from inshore to offshore. Marine communities on the extensive, subtidal, rocky reefs are poorly described. As a result, the current Habitat Classification System (HCS) used as part of the process to determine the marine park zoning arrangements, which places all shallow reef (<25 m) in the same category, is unlikely to represent real biotic patterns.

To evaluate the influence of five key factors (distance from shore, reef type, dominant benthos, latitude, and depth range) fish assemblages were widely surveyed, using 30‐minute timed counts, at 68 sites across the extent of shallow reef within the park. Relationships between assemblage patterns and levels of the different factors were subsequently examined using multivariate analyses.

Patterns of reef fish assemblages were most strongly correlated with distance from shore. Three distinct assemblages occurred on inshore (<1.5 km), mid‐shelf (1.5–6 km), and offshore (>6 km) reefs. Differences in assemblage structure by reef type were also apparent on inshore and offshore reefs, but not on mid‐shelf reefs. Correlations with the other factors were weak. The cross‐shelf pattern was persistent over the scale of years.

The results of the study provide strong support for incorporating distance‐from‐shore categories into a refined HCS. This will improve its ability to represent biological diversity as reflected by patterns of reef fish assemblages. Further research is required to determine the wider application of the HCS to other marine parks in NSW and to determine if it also, effectively, represents other components of biodiversity. Copyright © 2009 John Wiley & Sons, Ltd.
Conductive Nanoscopic Fibrous Assemblies Containing Helical Tetrathiafulvalene Stacks
Authors: Tatewaki Yoko , Hatanaka Tatsuya , Tsunashima Ryo , Nakamura Takayoshi , Kimura Mutsumi , Shirai Hirofusa
Published: June 2009

Tetrathiafulvalenes (TTF) S‐TTF and R‐TTF having four chiral amide end groups self‐organize into helical nanofibers in the presence of 2,3,5,6‐tetrafluoro‐7,7′,8,8′‐tetracyano‐p‐quinodimethane (F4TCNQ). The intermolecular hydrogen bonding among chiral amide end groups and the formation of charge‐transfer complexes results in a long one‐dimensional supramolecular stacking, and the chirality of the end groups affects the molecular orientation of TTF cores within the stacks. Electronic conductivity of a single helical nanoscopic fiber made of S‐TTF and F4TCNQ is determined to be (7.0±3.0)×10−4 S cm−1 by point‐contact current‐imaging (PCI) AFM measurement. Nonwoven fabric composed of helical nanofibers shows a semiconducting temperature dependence with an activation energy of 0.18 eV.
Superior Electron‐Transport Ability of π‐Conjugated Redox Molecular Wires Prepared by the Stepwise Coordination Method on a Surface
Authors: Nishimori Yoshihiko , Kanaizuka Katsuhiko , Kurita Tomochika , Nagatsu Toshiaki , Segawa Yu , Toshimitsu Fumiyuki , Muratsugu Satoshi , Utsuno Mitsuya , Kume Shoko , Murata Masaki , Nishihara Hiroshi
Published: June 2009

Electronic conductivity of molecular wires is a critical fundamental issue in molecular electronics. π‐Conjugated redox molecular wires with the superior long‐range electron‐transport ability could be constructed on a gold surface through the stepwise ligand–metal coordination method. The βd value, indicating the degree of decrease in the electron‐transfer rate constant with distance along the molecular wire between the electrode and the redox active species at the terminal of the wire, were 0.008–0.07 Å−1 and 0.002–0.004 Å−1 for molecular wires of bis(terpyridine)iron and bis(terpyridine)cobalt complex oligomers, respectively. The influences on βd by the chemical structure of molecular wires and the terminal redox units, temperature, electric field, and electrolyte concentration were clarified. The results indicate that facile sequential electron hopping between neighboring metal–complex units within the wire is responsible for the high electron‐transport ability.
Electronic and Steric Ligand Effects in the Radical Polymerization of Vinyl Acetate Mediated by β‐Ketoiminate Complexes of Cobalt(II)
Authors: K. S. Santhosh Kumar , Li Yugang , Gnanou Yves , Baisch Ulrich , Champouret Yohan , Poli Rinaldo , Robson Kiyoshi C. D. , McNeil W. Stephen
Published: June 2009

Complexes Co[OC(Ph)CHC(Me)NAr]2 [Ar=Ph, 1; o,o′‐C6H3Me2 (Xyl), 2; p‐C6H4CF3, 3] are tested in the polymerization of vinyl acetate (VAc) initiated by V‐70 (0.8 equiv) at 30 °C. Polymerization occurs without any notable induction time yielding PVAc with relatively low polydispersity, but with higher than expected Mn values, which indicates inefficient trapping processes. The apparent polymerization rate constant varies in the order 2>1>3. Controlled polymer growth is also observed when the polymerization is conducted in the presence of a much higher V‐70/1 ratio, demonstrating that this system can also function as a transfer agent in a degenerative transfer process. Competition between chain growth and catalyzed chain transfer (CCT) is also observed, the latter prevailing at higher temperatures. Comparison of these results with previous reports on bis(β‐diketonato) complexes allows a separate assessment of ligand electronic and steric effects in the ability to control polymerization.
Synthesis, Crystal Structure, and Photophysical Properties of (1E,3E,5E)‐1,3,4,6‐Tetraarylhexa‐1,3,5‐trienes: A New Class of Fluorophores Exhibiting Aggregation‐Induced Emission
Authors: Shimizu Masaki , Tatsumi Hironori , Mochida Kenji , Shimono Katsuhiro , Hiyama Tamejiro
Published: June 2009

Double Horner–Wadsworth–Emmons reaction of (E)‐2,3‐diaryl‐1,4‐bis(diethylphosphonyl)but‐2‐ene with (p‐substituted) benzaldehydes gave (1E,3E,5E)‐1,3,4,6‐tetraarylhexa‐1,3,5‐trienes in moderate to good yields. Substitution of electron‐withdrawing or ‐donating groups at the para position of the 1,6‐diphenyl groups induced a slight bathochromic shift of UV spectra measured in CHCl3 compared with that of the parent 1,3,4,6‐tetraphenylhexa‐1,3,5‐triene. Although fluorescence was not observed with all the trienes in CHCl3, they markedly emitted visible light in powder forms with quantum yields of 0.15–0.44. Introduction of amino groups at the para position of the 3,4‐diphenyl groups induced a bathochromic shift of emission maxima with good solid‐state quantum yields. Thus, the tetraarylated triene framework is found to serve as a new class of fluorophores that exhibit aggregation‐induced emission.
Nucleophilic Cyclopropanation Reaction with Bis(iodozincio)methane by 1,4‐Addition to α,β‐Unsaturated Carbonyl Compounds
Authors: Nomura Kenichi , Hirayama Takaharu , Matsubara Seijiro
Published: June 2009

Treatment of α,β‐unsaturated ketones with an electrophilic site at the γ‐position in the presence of trimethylsilyl cyanide with bis(iodozincio)methane afforded the (Z)‐silyl enol ether of the β‐cyclopropyl substituted ketone in good yields. The reaction proceeds by 1,4‐addition to form an enolate, and its sequential intramolecular nucleophilic attack to an adjacent electrophilic site. The reaction of γ‐ethoxycarbonyl‐α,β‐unsaturated ketone and bis(iodozincio)methane in the presence of trimethylsilyl cyanide afforded 1‐ethoxy‐1‐trimethylsiloxycyclopropane derivatives, which can be regarded as the homoenolate equivalent. Additionally, reaction of the obtained homoenolate equivalents with imines give 1‐(E)‐alkenyl‐2‐(1‐aminoalkyl)alkanols diastereoselectively.
A Photoelectrochemical Method for Determining the Kinematics of Moving Particles Using an Array of Individually Addressable Electrodes
Authors: Rees Neil V. , Compton Richard G.
Published: June 2009

We present the novel use of photoelectrochemistry to detect and monitor the trajectory of moving spheres. Using an array of individually addressable electrodes under illumination and potentiostatted so that a photocurrent is generated, the motion of a sphere is detected by means of measuring “dark” transients as the shadow cast by the moving sphere passes over each electrode. The method can used to determine the size and velocity of a single ball, or simultaneously track two spheres in collision.
Ultra scale‐down approach to correct dispersive and retentive effects in small‐scale columns when predicting larger scale elution profiles
Authors: Hutchinson N. , Chhatre S. , Baldascini H. , Davies J. L. , Bracewell D. G. , Hoare M.
Published: June 2009

Ultra scale‐down approaches represent valuable methods for chromatography development work in the biopharmaceutical sector, but for them to be of value, scale‐down mimics must predict large‐scale process performance accurately. For example, one application of a scale‐down model involves using it to predict large‐scale elution profiles correctly with respect to the size of a product peak and its position in a chromatogram relative to contaminants. Predicting large‐scale profiles from data generated by small laboratory columns is complicated, however, by differences in dispersion and retention volumes between the two scales of operation. Correcting for these effects would improve the accuracy of the scale‐down models when predicting outputs such as eluate volumes at larger scale and thus enable the efficient design and operation of subsequent steps. This paper describes a novel ultra scale‐down approach which uses empirical correlations derived from conductivity changes during operation of laboratory and pilot columns to correct chromatographic profiles for the differences in dispersion and retention. The methodology was tested by using 1 mL column data to predict elution profiles of a chimeric monoclonal antibody obtained from Protein A chromatography columns at 3 mL laboratory‐ and 18.3 L pilot‐scale. The predictions were then verified experimentally. Results showed that the empirical corrections enabled accurate estimations of the characteristics of larger‐scale elution profiles. These data then provide the justification to adjust small‐scale conditions to achieve an eluate volume and product concentration which is consistent with that obtained at large‐scale and which can then be used for subsequent ultra scale‐down operations. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009
Recovery of E,E‐farnesol from cultures of yeast erg9 mutants: Extraction with polymeric beads and purification by normal‐phase chromatography
Authors: Song Linsheng
Published: June 2009

Saccharomyces cerevisiae erg9 mutants blocked at squalene synthase require ergosterol for growth and produce E,E‐farnesol. Typically, at least half the amount of farnesol remains cell associated. Practically insoluble in water, farnesol can be extracted from production cultures of the erg9 mutants using either methanol/hexane or poly(styrene‐co‐divinylbenzene) beads. The first method consumes more solvents and requires centrifugation to clear an interface emulsion. The second method uses 50% less solvent and the beads can be used repeatedly for extraction. The solvent‐free crude extract from the beads extraction contained higher concentration of farnesol (76–77%) than that from the solvent extraction (61–65%). Farnesol was obtained after normal‐phase chromatography in high overall recovery (94%) and purity (99%). © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009
Antifungal Activity of Alkaloids from the Seeds of Chimonanthus praecox
Authors: Zhang Ji‐Wen , Gao Jin‐Ming , Xu Tian , Zhang Xing‐Chang , Ma Ya‐Tuan , Jarussophon Suwatchai , Konishi Yasuo
Published: June 2009

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Two alkaloids, D‐calycanthine (1) and L‐folicanthine (2), were isolated from the active MeOH extract of the seeds of Chimonanthus praecox Link. The structures of the two compounds were established by 1H‐ and 13C‐NMR, and MS (FAB, ESI) analyses. In the in vitro tests, compounds 1 and 2 showed significant inhibitory activities against five plant pathogenic fungi Exserohilum turcicum, Bipolaris maydis, Alternaria solani, Sclerotinia sderotiorum, and Fusarium oxysportium, among which B. maydis was found to be the most susceptible to 1 with an EC50 value of 29.3 μg/ml, followed by S. sderotiorum to 2 with an EC50 value of 61.2 μg/ml. To our knowledge, this is the first report of isolation and LC/MS/MS identification as well as of antifungal properties of these alkaloids from the seeds of this plant.