bluuebunny/crossref_metadata_2025 huggingface dataset:
Preparation and antimicrobial activity of Konjac Glucomannan modified with quaternary ammonium compound
Authors: Lei Wanxue , Yang Qinhuan , Jia Xingang , Zhang Tingyou
Published: July 2010

Seven kind of graft copolymerization Konjac Glucomannan with quaternary ammonium group have been prepared, using Konjac Glucomannan (KGM) and methacryloxylethyl alkyl dimethyl ammonium bromide with c8–c18 alkyl and benzyl in water, ceric ammonium nitrate as initiator, the reaction temperature of 348 K, and the reaction period of 3 h. The structures were confirmed by FTIR. The 15 min inhibitory rates of all the graft copolymerization KGM against Escherichia coli and Staphylococcus aureus reached 99.99%, against Candida albicans somewhat lower, but 30 min inhibitory rate still reached 99.02% for graft copolymerization KGM with quaternary ammonium group having 14 alkyl. The antibacterial mechanism of the graft copolymerization KGM has been investigated by adsorption ability to E. coli, measure of 260 nm absorbing materials and SEM micrographs. Firstly, the bacteria were fastly adsorbed by graft copolymerization KGM. Interactions between bacterial membranes and antibacterial product cause fundamental changes in both membrane structure and function, induced leakage of cytoplasmic contents is a classic indication of damage to the bacterial cytoplasmic membrane. The loss of the connection between the outer membrane and the underlying peptidoglycan induces the abnormality of nodular structures and bleb formation of the cell envelope of E. coli. The antibacterial mechanism is in accordance with microbiologic findings identifying surface blebbing as the first morphologic change occurring in the permeability barrier of gram‐negative bacteria under mild heat stress and laser irradiation, etc. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Properties of compression‐molded plates made from wood powders impregnated with liquefied wood‐based novolak‐type phenol‐formaldehyde resins
Authors: Lee Wen‐Jau , Wu Yun‐Hsuan , Wu Chiou‐Chang , Chang Kuo‐Chun , Tseng I‐Min
Published: July 2010

Novolak‐type phenol‐formaldehyde (PF) resins with solution form were prepared by reacting phenol‐liquefied Cryptomeria japonica (Japanese cedar) wood with formalin in the presence of methanol. Wood powders of Albizzia falcate (Malacca albizzia) impregnated with these resins were air dried followed by an oven‐dried at 60°C. DSC analysis showed the PF resin existing in wood powders could be melted, and could be cured if hexamine was mixed and heated at high temperature. Compression‐molded plates made with PF resin impregnated woods had a high degree of curing reaction. However, compression‐molded plates hot‐pressed at 180°C for 8 min or 200°C for 5 min had better internal bonding strength and dimensional stability than others. Premixing hexamine with PF resin and impregnating into wood powders simultaneously could enhance the reactivity of PF resin, but it was not useful for improving the properties of compression‐molded plates. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Highly purified natural rubber by saponificaion of latex: Analysis of green and cured properties
Authors: Amnuaypornsri Sureerut , Sakdapipanich Jitladda , Tanaka Yasuyuki
Published: July 2010

Natural rubber (NR) was purified by saponification of fresh latex from Hevea brasiliensis and soaking process of the coagulum with aqueous NaOH solution. This treatment resulted in the decrease of nitrogen content to the same level as enzymatic deproteinized NR. The saponification of NR latex and soaking of the coagulum gave the rubber having good processability with easy to cure. The saponified rubber showed outstanding physical and dynamic mechanical properties such as high tensile properties, high storage modulus, low tan δ, low heat build‐up and low dynamic compression set. The saponified rubber blend with styrene butadiene rubber (SBR) according to the recipe of rubber tire showed also a good performance. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Radiation processing and characterization of poly(vinyl alcohol) nano‐composites, Part 1: Nano‐particulate filler tuned crosslinking behavior
Authors: Dubey Kumar A. , Chaudhari Chandrasekhar V. , Rao Rekha , Bhardwaj Yatender K. , Goel Narender K. , Sabharwal Sunil
Published: July 2010

Nano‐composites of poly vinyl alcohol containing different nano‐fillers namely multiple walled carbon nanotubes (MWNT), single walled carbon nanotubes (SWNT), silica nanoparticles, and silver nanoparticles were prepared by sonication‐assisted solution mixing and subjected to different doses of gamma radiation. The efficacy of radiation crosslinking was analyzed by sol–gel analysis, Charlesby‐Pinner parameter estimation and crosslinking density measurements. Crosslinking of nano‐composites was found to increase with radiation dose and markedly affected with the type of nano‐particulate filler in the matrix (po/qo in the range: 0.40–0.83). The results have been explained on the basis of Raman spectroscopy, hydrodynamic volume measurements, contact angle measurements, and scanning electron microscopy (SEM). © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Evaluation effects of biobased plasticizer on the thermal, mechanical, dynamical mechanical properties, and permanence of plasticized PVC
Authors: Benaniba Mohamed Tahar , Massardier‐Nageotte Valérie
Published: July 2010

Sunflower oil (SO) is a renewable resource that can be epoxidized, and the epoxidized SO has potential uses as an environmentally friendly in polymeric formulations, especially for poly (vinyl chloride) (PVC). Epoxidized sunflower oil (ESO) was prepared by treating the oil with peracetic acid generated in situ by reacting glacial acetic acid with hydrogen peroxide. Epoxidation was confirmed using spectroscopic and titration methods. ESO was used as a coplasticizer in PVC for the partial replacement of di‐(2‐ethyl hexyl) phthalate (DEHP). The effect of ESO on the thermal stability of plasticized PVC was evaluated by using synmero scale for the sheets. In presence of ESO plasticized PVC samples showed a reduction in discoloration and the number of conjugated double bonds. By using thermogravimetry, the incorporation of 15/45 of ESO/DEHP in PVC presents the lowest weight loss. The results of the shore hardness and mechanical properties showed that a proportion of DEHP could be substituted by ESO. By use of DMA, the formulation which contains 25 % wt of ESO in plasticizer system shifts the glass transition temperature (Tg) to ambient temperature. The migration phenomenon was studied on PVC based samples plasticized with DEHP and ESO in varying amounts. The migration was monitored by the weight loss percentage of the samples immersed into n‐hexane or heated in an oven. The amount of extracted or volatilized DEHP is proportional to the added ratio of ESO in plasticizer system. All of this favored the partial replacement of DEHP by ESO as biobased plasticizer for flexible PVC. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Novel polymeric flocculants based on polyacrylamide grafted dextran in kaolin suspension
Authors: Krishnamoorthi S. , Adhikary P. , Mal D. , Singh R. P.
Published: July 2010

A study is done on ceric‐ammonium‐nitrate (CAN) initiated graft copolymerization of polyacrylamide (PAM) on to dextran (Dx) by solution polymerization technique. The average molecular weight of dextran is 7.0 × 10−6 g/mole. By changing the concentrations of the initiator in the reaction feed, a series of graft copolymer (Dx‐g‐PAM1 to Dx‐g‐PAM4) with variation in the number and length of the grafted PAM chains are obtained. The flocculation characteristics of various polymers are investigated by the use of settling tests in 2 wt % using kaolin suspensions. Among the series of graft copolymers, the one with highest molecular weight shows superior performance. The flocculation characteristics of the best‐performing graft copolymer (Dx‐g‐PAM3) are compared with those of various commercially available flocculants and PAM in the kaolin suspension. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Amphiphilic PEG‐based ether‐anhydride terpolymers: Synthesis, characterization, and micellization
Authors: Zhao Aijun , Zhou Qi , Chen Tao , Weng Jie , Zhou Shaobing
Published: July 2010

A series of amphiphilic poly(ether‐anhydrides) terpolymers composed of sebacic acid, 1,3‐bis(carboxyphenoxy) propane, and poly(ethylene glycol) (PEG) were synthesized via melt‐condensation polymerization. The resultant terpolymers were characterized by 1H‐nuclear magnetic resonance spectroscopy (1H‐NMR), Fourier transform infrared spectroscopy, gel permeation chromatography, X‐ray diffraction, polarization optical microscope, differential scanning calorimeter, and water contact angle. Biodegradable micelles were prepared via a precipitation method through self‐emulsification. The shape of these micelles was uniform and spheric according to the atomic force microscopy and transmission electron microscopy images. The dynamic light scattering measurements indicated that the diameters of micelles were typically in the range of 118–359 nm. The results displayed the PEG‐based ether‐anhydride terpolymers may be of great potential as nanoscaled carriers for drug delivery system. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Isothermal crystallization kinetics and crystal structure of poly(lactic acid): Effect of triphenyl phosphate and talc
Authors: Xiao H. W. , Li Peng , Ren Xiaomin , Jiang Tao , Yeh Jen‐Taut
Published: July 2010

In this article, kinetics of neat poly(lactic acid) (PLA) and its blends with triphenyl phosphate (TPP) and/or talc crystallized isothermally in the temperature range of 113–128°C was analyzed by differential scanning calorimetry (DSC) and described by the Avrami equation. The results showed that the average value of Avrami exponents n is around 2.0 for neat PLA and the PLA/15TPP blend, and around 3.0 for the PLA/1.2Talc blend and the PLA/15TPP/1.2Talc blend. The crystallization rate constants k for neat PLA and its blends were increased in the following order: the PLA/15TPP blend, neat PLA, the PLA/15TPP/1.2Talc blend, and PLA/1.2Talc blend. The half‐time of crystallization t1/2 was increased with an increase of crystallization temperature Tc and the presence of TPP, and was decreased sharply with the incorporation of talc. Further investigation into crystallization activation energy ΔEa of neat PLA and its blends with 15 wt % TPP and/or 1.2 wt % talc showed that the values of ΔEa were increased with the incorporation of TPP and/or talc compared to that of neat PLA. It was verified by wide angle X‐ray diffraction (WAXD) that neat PLA and its blends with TPP and/or talc crystallized isothermally in the temperature range of 113–128°C, and all formed the α‐form crystal after enough annealing time. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010
Retrieval effectiveness of machine translated queries
Authors: Dolamic Ljiljana , Savoy Jacques
Published: July 2010

This article describes and evaluates various information retrieval models used to search document collections written in English through submitting queries written in various other languages, either members of the Indo‐European family (English, French, German, and Spanish) or radically different language groups such as Chinese. This evaluation method involves searching a rather large number of topics (around 300) and using two commercial machine translation systems to translate across the language barriers. In this study, mean average precision is used to measure variances in retrieval effectiveness when a query language differs from the document language. Although performance differences are rather large for certain languages pairs, this does not mean that bilingual search methods are not commercially viable. Causes of the difficulties incurred when searching or during translation are analyzed and the results of concrete examples are explained.
Active disturbance rejection control for power plant with a single loop
Authors: Xia Yuanqing , Liu Bo , Fu Mengyin
Published: July 2010

The cascade proportional‐integral‐derivative (PID) control method is widely used in power plant control field. In this paper, an active disturbance rejection control (ADRC) for a power plant with a single loop is introduced for eliminating the shortcomings of the cascade PID control method. The proposed controller based on the ADRC method consists of a tracking differentiator (TD), an extended state observer (ESO) and a nonlinear combination of errors. In this approach, the processes with higher orders, uncertainties and unmodeled dynamics are viewed as lower‐ordered systems with general disturbances, and the general disturbances are estimated by ESO, and then actively compensated. Besides, only one measured output is needed in the proposed method instead of two or three in the cascade PID control method. Some simulation studies compared with the regular cascade PID control method show the proposed method has better performance beyond the regular cascade PID control method.

Copyright © 2010 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society
Peroxidase activity of bacterial cytochrome P450 enzymes: Modulation by fatty acids and organic solvents
Authors: Rabe Kersten S. , Erkelenz Michael , Kiko Kathrin , Niemeyer Christof M.
Published: July 2010

The modulation of peroxidase activity by fatty acid additives and organic cosolvents was determined and compared for four bacterial cytochrome P450 enzymes, thermostable P450 CYP119A1, the P450 domain of CYP102A1 (BMP), CYP152A1 (P450bsβ), and CYP101A1 (P450cam). Utilizing a high‐throughput microplate assay, we were able to readily screen more than 100 combinations of enzymes, additives and cosolvents in a convenient and highly reproducible assay format. We found that, in general, CYP119A1 and BMP showed an increase in peroxidative activity in the presence of fatty acids, whereas CYP152A1 revealed a decrease in activity and CYP101A1 was only slightly affected. In particular, we observed that the conversion of the fluorogenic peroxidase substrate Amplex Red by CYP119A1 and BMP was increased by a factor of 38 or 11, respectively, when isopropanol and lauric acid were present in the reaction mixture. The activity of CYP119A1 could thus be modulated to reach more than 90% of the activity of CYP152A1 without effectors, which is the system with the highest peroxidative activity. For all P450s investigated we found distinctive reactivity patterns, which suggest similarities in the binding site of CYP119A1 and BMP in contrast with the other two proteins studied. Therefore, this study points towards a role of fatty acids as activators for CYP enzymes in addition to being mere substrates. In general, our detailed description of fatty acid‐ and organic solvent‐effects is of practical interest because it illustrates that optimization of modulators and cosolvents can lead to significantly increased yields in biocatalysis.
Ensembles of signal transduction models using Pareto Optimal Ensemble Techniques (POETs)
Authors: Song Sang Ok , Chakrabarti Anirikh , Varner Jeffrey D.
Published: July 2010

Mathematical modeling of complex gene expression programs is an emerging tool for understanding disease mechanisms. However, identification of large models sometimes requires training using qualitative, conflicting or even contradictory data sets. One strategy to address this challenge is to estimate experimentally constrained model ensembles using multiobjective optimization. In this study, we used Pareto Optimal Ensemble Techniques (POETs) to identify a family of proof‐of‐concept signal transduction models. POETs integrate Simulated Annealing (SA) with Pareto optimality to identify models near the optimal tradeoff surface between competing training objectives. We modeled a prototypical‐signaling network using mass‐action kinetics within an ordinary differential equation (ODE) framework (64 ODEs in total). The true model was used to generate synthetic immunoblots from which the POET algorithm identified the 117 unknown model parameters. POET generated an ensemble of signaling models, which collectively exhibited population‐like behavior. For example, scaled gene expression levels were approximately normally distributed over the ensemble following the addition of extracellular ligand. Also, the ensemble recovered robust and fragile features of the true model, despite significant parameter uncertainty. Taken together, these results suggest that experimentally constrained model ensembles could capture qualitatively important network features without exact parameter information.
Lipase‐catalyzed dimethyl adipate synthesis: Response surface modeling and kinetics
Authors: Chaibakhsh Naz , Rahman Mohd Basyaruddin Abdul , Basri Mahiran , Salleh Abu Bakar , Abd‐Aziz Suraini
Published: July 2010

Dimethyl adipate (DMA) was synthesized by immobilized Candida antarctica lipase B‐catalyzed esterification of adipic acid and methanol. To optimize the reaction conditions of ester production, response surface methodology was applied, and the effects of four factors namely, time, temperature, enzyme concentration, and molar ratio of substrates on product synthesis were determined. A statistical model predicted that the maximum conversion yield would be 97.6%, at the optimal conditions of 58.5°C, 54.0 mg enzyme, 358.0 min, and 12:1 molar ratio of methanol to adipic acid. The R2 (0.9769) shows a high correlation between predicted and experimental values. The kinetics of the reaction was also investigated in this study. The reaction was found to obey the ping‐pong bi‐bi mechanism with methanol inhibition. The kinetic parameters were determined and used to simulate the experimental results. A good quality of fit was observed between the simulated and experimental initial rates.
Microbial 1‐butanol production: Identification of non‐native production routes and in silico engineering interventions
Authors: Ranganathan Sridhar , Maranas Costas D.
Published: July 2010

The potential of engineering microorganisms with non‐native pathways for the synthesis of long‐chain alcohols has been identified as a promising route to biofuels. We describe computationally derived predictions for assembling pathways for the production of biofuel candidate molecules and subsequent metabolic engineering modifications that optimize product yield. A graph‐based algorithm illustrates that, by culling information from BRENDA and KEGG databases, all possible pathways that link the target product with metabolites present in the production host are identified. Subsequently, we apply our recent OptForce procedure to pinpoint reaction modifications that force the imposed product yield in Escherichia coli. We demonstrate this procedure by suggesting new pathways and genetic interventions for the overproduction of 1‐butanol using the metabolic model for Escherichia coli. The graph‐based search method recapitulates all recent discoveries based on the 2‐ketovaline intermediate and hydroxybutyryl‐CoA but also pinpointes one novel pathway through thiobutanoate intermediate that to the best of our knowledge has not been explored before.
Lentivirus‐mediated knockdown of aggrecanase‐1 and ‐2 promotes chondrocyte‐engineered cartilage formation in vitro
Authors: Wang Zheng‐Hui , Yang Zhuang‐Qun , He Xi‐Jing , Kamal B. Elnour , Xing Zhe
Published: July 2010

Chondrocyte‐based tissue engineering has emerged as a promising approach for repair of injured cartilage tissues that have a poor self‐healing capacity. However, this technique faces a major limitation: dedifferentiation of chondrocytes occurs following several passages in culture. Aggrecan, a major component of cartilage extracellular matrix, plays an essential role in chondrocyte differentiation. The aim of this study is to determine whether inhibition of chondrocyte aggrecanases, key degradative enzymes for aggrecan in cartilage, could benefit chondrocyte differentiation and the preservation of chondrocyte phenotype within a long‐term period. Lentivirus‐mediated RNA interference (RNAi) was employed to target both aggrecanase‐1 and ‐2 in primary rat chondrocytes, and the transduced cells were seeded into chitosan–gelatin three‐dimensional scaffolds. Histological, morphological, and biochemical analyses were performed at 1–8 weeks post‐implantation to study chondrocyte survival, differentiation, and function. We found that lentivirus‐mediated RNAi notably decreased the abundance of aggrecanase transcripts in chondrocytes but did not affect cell viability. Most importantly, compared to the control constructs seeded with untransduced chondrocytes, the aggrecanase inhibition increased chondrocyte proliferation and reinforced the production of glycosaminoglycans and total collagen, indicative of chondrocyte differentiation. The mRNA expression of chondrocyte marker genes (collagen II and aggrecan) was enhanced by aggrecanase silencing relative to the control. Together our data demonstrate that inhibition of endogenous aggrecanases facilitates chondrocyte differentiation and chondrocyte‐engineered cartilage formation in vitro. The combination of lentiviral delivery system and genetic manipulation techniques provides a useful tool for modulation of chondrocyte phenotype in cartilage engineering. Biotechnol. Bioeng. 2010;107:730–736. © 2010 Wiley Periodicals, Inc.
Improved specific productivity in cephalexin synthesis by immobilized PGA in silica magnetic micro‐particles
Authors: Bernardino Susana M.S.A. , Fernandes Pedro , Fonseca Luís P.
Published: July 2010

There is a marked trend in pharmaceutical industry towards the replacement of classical organic methods by “green” alternatives that minimize or eliminate the generation of waste and avoid, where possible, the use of toxic and/or hazardous reagents and solvents. In this work the kinetically controlled synthesis of cephalexin by soluble and penicillin G acylase immobilized in sol–gel micro‐particles with magnetic properties was performed in aqueous media with PGME and 7‐ADCA as substrates, at different concentrations of substrate, temperature, pH, enzyme to substrate ratio and acyl donor to nucleophile ratio. Excess acyl donor had a strong effect on cephalexin productivity. A PGME/7‐ADCA ratio of 3 was considered optimum. A maximum specific productivity of $5.9\,{\rm mmol}\,{\rm h}^{ - 1} \,{\rm g}_{{\rm biocatalyst}}^{ - 1} $ at 160 mM 7‐ADCA, 480 mM PGME and low enzyme to substrate ratio at 32.5 U mmol−1 7‐ADCA was obtained with immobilized PGA in full aqueous medium, suggesting that diffusional limitations were minimized when compared with other commercial biocatalysts. A half‐life of 133 h for the immobilized biocatalyst was estimated during cephalexin synthesis in the presence of 100 mM 7‐ADCA and 300 mM PGME, in 50 mM Tris/HCl at pH 7.2 and 14°C. These results compare quite favorably with those previously reported for the kinetically controlled synthesis of cephalexin. Biotechnol. Bioeng. 2010;107: 753–762. © 2010 Wiley Periodicals, Inc.
Broadening the cofactor specificity of a thermostable alcohol dehydrogenase using rational protein design introduces novel kinetic transient behavior
Authors: Campbell Elliot , Wheeldon Ian R. , Banta Scott
Published: July 2010

Cofactor specificity in the aldo‐keto reductase (AKR) superfamily has been well studied, and several groups have reported the rational alteration of cofactor specificity in these enzymes. Although most efforts have focused on mesostable AKRs, several putative AKRs have recently been identified from hyperthermophiles. The few that have been characterized exhibit a strong preference for NAD(H) as a cofactor, in contrast to the NADP(H) preference of the mesophilic AKRs. Using the design rules elucidated from mesostable AKRs, we introduced two site‐directed mutations in the cofactor binding pocket to investigate cofactor specificity in a thermostable AKR, AdhD, which is an alcohol dehydrogenase from Pyrococcus furiosus. The resulting double mutant exhibited significantly improved activity and broadened cofactor specificity as compared to the wild‐type. Results of previous pre‐steady‐state kinetic experiments suggest that the high affinity of the mesostable AKRs for NADP(H) stems from a conformational change upon cofactor binding which is mediated by interactions between a canonical arginine and the 2′‐phosphate of the cofactor. Pre‐steady‐state kinetics with AdhD and the new mutants show a rich conformational behavior that is independent of the canonical arginine or the 2′‐phosphate. Additionally, experiments with the highly active double mutant using NADPH as a cofactor demonstrate an unprecedented transient behavior where the binding mechanism appears to be dependent on cofactor concentration. These results suggest that the structural features involved in cofactor specificity in the AKRs are conserved within the superfamily, but the dynamic interactions of the enzyme with cofactors are unexpectedly complex. Biotechnol. Bioeng. 2010;107: 763–774. © 2010 Wiley Periodicals, Inc.
Thermostability Enhancement of Clostridium thermocellum Cellulosomal Endoglucanase Cel8A by a Single Glycine Substitution
Authors: Anbar Michael , Lamed Raphael , Bayer Edward A.
Published: July 2010

The thermostability of endoglucanase (E.C. 3.2.1.4) Cel8A, a major component of the cellulosome complex from Clostridium thermocellum, was significantly enhanced using a directed evolution strategy. To ensure that thermostability would not compromise enzyme activity, a two‐step screening strategy was employed that involved consecutive activity and thermostability assays. We have combined three of the mutations from the thermostability screen to obtain a Cel8A variant with a significant increase in thermal resistance without substantial alteration of kinetic parameters. One of the three mutations (S329G) provided the highest contribution to enzyme stability. This single mutation served to increase the Tm by 7.0 °C and the half‐life of activity by eight fold at 85 °C. Site‐saturation mutagenesis at position 329 revealed that only the glycine residue could confer thermostability. The structural changes responsible for the properties of the mutant enzymes are discussed.
ChemInform Abstract: Alumina Supported Synthesis of β‐Lactams Using Microwave.
Authors: Kidwai M. , Venkataramanan R. , Kohli S.
Published: July 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Guanylpiperidine Peptidomimetics: Potent and Selective Bis‐Cation Inhibitors of Factor Xa.
Authors: Semple J. Edward , et al. et al.
Published: July 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Gas‐Phase Vanadium Oxide Anions: Structure and Detachment Energies from Density Functional Calculations.
Authors: Vyboishchikov Sergei F. , Sauer Joachim
Published: July 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
ChemInform Abstract: Chiral Synthesis and Pharmacological Evaluation of NPS 1407: A Potent, Stereoselective NMDA Receptor Antagonist.
Authors: Moe Scott T. , et al. et al.
Published: July 2010

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
Make them Blink: Probes for Super‐Resolution Microscopy
Authors: Vogelsang Jan , Steinhauer Christian , Forthmann Carsten , Stein Ingo H. , Person‐Skegro Britta , Cordes Thorben , Tinnefeld Philip
Published: July 2010

In recent years, a number of approaches have emerged that enable far‐field fluorescence imaging beyond the diffraction limit of light, namely super‐resolution microscopy. These techniques are beginning to profoundly alter our abilities to look at biological structures and dynamics and are bound to spread into conventional biological laboratories. Nowadays these approaches can be divided into two categories, one based on targeted switching and readout, and the other based on stochastic switching and readout of the fluorescence information. The main prerequisite for a successful implementation of both categories is the ability to prepare the fluorescent emitters in two distinct states, a bright and a dark state. Herein, we provide an overview of recent developments in super‐resolution microscopy techniques and outline the special requirements for the fluorescent probes used. In combination with the advances in understanding the photophysics and photochemistry of single fluorophores, we demonstrate how essentially any single‐molecule compatible fluorophore can be used for super‐resolution microscopy. We present examples for super‐resolution microscopy with standard organic fluorophores, discuss factors that influence resolution and present approaches for calibration samples for super‐resolution microscopes including AFM‐based single‐molecule assembly and DNA origami.
Regional expression of the ADAMs in developing chicken cochlea
Authors: Yan Xin , Lin Juntang , Wang Hong , Markus Annett , Wree Andreas , Rolfs Arndt , Luo Jiankai
Published: July 2010

The expression patterns of five members of the ADAM (a disintegrin and metalloprotease) family including ADAM9, ADAM10, ADAM17, ADAM22, and ADAM23 were analyzed in different anatomical structures of the developing chicken cochlea by in situ hybridization and immunohistochemistry. Results show that ADAM9, ADAM10, and ADAM17 are widely expressed in the sensory epithelium of the basilar papilla, by homogene cells, spindle‐shaped cells, and acoustic ganglion cells, and in the tegmentum vasculosum, each with a different pattern. ADAM22 expression is restricted to spindle‐shaped cells and acoustic ganglion cells, while ADAM23 is prominently expressed by hair cells and acoustic ganglion cells. Furthermore, ADAM10 protein is coexpressed with several members of the classic cadherins, including cadherin‐7, N‐cadherin, and R‐cadherin in distinct anatomical regions of the cochlea except for acoustic ganglion cells. The expression of the ADAMs in the developing cochlea suggests a contribution of the ADAMs to the development of distinct cochlear structures. Developmental Dynamics 239:2256–2265, 2010. © 2010 Wiley‐Liss, Inc.
The relationship between dlx and gad1 expression indicates highly conserved genetic pathways in the zebrafish forebrain
Authors: MacDonald Ryan B. , Debiais‐Thibaud Mélanie , Talbot Jared Coffin , Ekker Marc
Published: July 2010

The Dlx genes encode a family of transcription factors important for the development of the vertebrate forebrain. These genes have very similar expression domains during the development of the telencephalon in mice and play a role in γ‐aminobutyric acid (GABAergic) interneuron differentiation. We have used triple fluorescent in situ hybridization to study the relative expression domains of the dlx and gad1 genes in the zebrafish telencephalon and diencephalon. We also generated transgenic zebrafish with regulatory elements from the zebrafish dlx1a/2a locus. The zebrafish dlx regulatory elements recapitulated dlx expression in the forebrain and mimicked the relationship between the expression of the dlx genes and gad1. Finally, we show that a putative enhancer located downstream of dlx2b can also activate reporter gene expression in a tissue‐specific manner similar to endogenous dlx2b expression. Our results indicate the dlx genes are regulated by an evolutionarily conserved genetic pathway and may play a role in GABAergic interneuron differentiation in the zebrafish forebrain. Developmental Dynamics 239:2298–2306, 2010. © 2010 Wiley‐Liss, Inc.
Selective Separation of the Sulfate Anion by In Situ Crystallization of CdII Coordination Compounds Derived from Bis(pyridyl) Ligands Equipped with a Urea/Amide Hydrogen‐Bonding Backbone
Authors: Banerjee Subhabrata , Adarsh N. N. , Dastidar Parthasarathi
Published: July 2010

Five new coordination compounds, namely [{Cd(μ‐L1)(μ‐SO4)(H2O)2}·MeOH]∞ (1), [{Cd(μ‐L2)2(SO4)(H2O)}·3.5H2O]∞ (2), [{Cd(μ‐L3)(SO4)(H2O)3}·MeOH]∞ (3), [{Cd(L4)4(H2O)2}·SO4·8H2O] (4) and [{Cd(μ‐L5)(μ3‐SO4)(H2O)}·2H2O]∞ (5), [L1 = N‐(3‐picolyl)‐N′‐(3‐pyridyl)urea, L2 = N‐(4‐picolyl)‐N′‐(3‐pyridyl)urea, L3 = N,N′‐di‐3‐pyridylurea, L4 = N,N′‐di‐4‐pyridylurea and L5 = N,N′‐di‐3‐pyridylnicotinamide] have been synthesized and characterized by single‐crystal X‐ray diffraction. It is revealed that the positional isomers L1,L2 and L3,L4 play a crucial role in determining the resultant supramolecular structures of 1–4. Various supramolecular architectures, that is, a 3D coordination polymer (1), a 1D looped‐chain coordination polymer (2), a 1D zigzag coordination polymer (3), a discrete coordination complex (4) and a 2D corrugated sheet (5), were observed. In situ crystallization of compound 2 under competitive crystallization conditions inthe presence of competing anions such as SO42–, NO3–, ClO4–,AcO–, Cl– and Br– resulted in the isolation of 2, which indicates the selective separation of SO42– from an aqueous mixture of other competing anions, as revealed by FTIR spectroscopy, X‐ray powder diffraction and elemental analysis. The X‐ray structure of 2 indicates that both intermolecular hydrogen bonding and metal–ligand coordination of SO42– play an important role in the selective separation of SO42–. A similar competitive crystallization also resulted in selective SO42– separation in the form of compound 5, as determined by FTIR spectroscopy and elemental analysis.
27‐ to 39‐Membered Pyridine Macrocycles
Authors: Lüning Ulrich , Mak Ellen , Zindler Melanie , Hartkopf Britta , Herges Rainer
Published: July 2010

A set of 27‐ to 39‐membered pyridine macrocycles2and3has been synthesized by Williamson ether synthesis or ring‐closing metathesis. The pyridines are 2,6‐disubstituted to allowendointeractions. In addition to the length, also thenature of the aliphatic chain was varied: saturated (2) and unsaturated (3).
Exploring Lemna gibba thresholds to nutrient and chemical stressors: Differential effects of triclosan on internal stoichiometry and nitrate uptake across a nitrogen:phosphorus gradient
Authors: Fulton Barry A. , Brain Richard A. , Usenko Sascha , Back Jeffrey A. , Brooks Bryan W.
Published: July 2010

Nutrient enrichment often co-occurs with chemical stressors in aquatic ecosystems, but the impacts of these multiple stressors across nutrient gradients is poorly understood and not typically addressed in ecotoxicity studies of lower trophic level models. Moreover, laboratory assays performed to determine threshold responses of aquatic macrophytes to contaminants typically use growth and morphometric endpoints to establish threshold effects and seldom report other important functional responses of lower trophic levels. Using the aquatic macrophyte Lemna gibba, we examined influences of varying nitrogen (N) and phosphorus (P) levels in combination with triclosan, a widely used antimicrobial agent in consumer care products, on internal carbon (C):N:P and NO 3− uptake kinetics. Triclosan modulated L. gibba tissue N and P content, and these stoichiometric responses for P-limited plants to triclosan exposure were more sensitive than growth endpoints employed in standardized phytotoxicity assays. Nitrate uptake capacities were also differentially inhibited by triclosan exposure according to external nutrient levels. Uptake rates for plants cultured and exposed under saturating N-levels were inhibited by more than threefold compared with N-limited plants. The results suggest that stoichiometric and nutrient uptake responses to chemical stressors provide useful information regarding adverse ecological thresholds not defined in standardized phytotoxicity assays with aquatic macrophytes. Our findings further indicate that site-specific impacts of chemicals associated with the wide ambient ranges of N and P typical of surface waters may be anticipated in lower trophic levels. Future studies should examine adverse effects of other stressors to these ecologically relevant endpoints, which may be useful in environmental assessment and management. Environ. Toxicol. Chem. 2010;29:2363–2370. © 2010 SETAC
Early signs of lethal effects in Daphnia magna (Branchiopoda, Cladocera) exposed to the insecticide cypermethrin and the fungicide azoxystrobin
Authors: Friberg-Jensen Ursula , Nachman Gösta , Christoffersen Kirsten S.
Published: July 2010

This study presents the effects of sublethal concentrations of pesticides cypermethrin and azoxystrobin on the activity of several physiological parameters of egg-carrying Daphnia magna studied using a video-image technique. Single tethered daphnids were continuously recorded for 24 h of pesticide exposure, and the activity of the heart, the filtering limbs, the mandibles, and the focal spine were subsequently analyzed. Acute toxicity tests based on the criteria of immobilization were performed on egg-carrying D. magna, and sublethal concentrations of 0.1, 1.0, and 10 µg/L cypermethrin and 0.5, 1.0, and 2.0 mg/L azoxystrobin were established. At a concentration as low as 0.1 µg/L cypermethrin, the 5% effective concentration after 24 h of exposure (EC5,24h), the activity of the focal spine increased and the filtering limb activity decreased. The activity of the mandibles was reduced by exposure to 1.0 (EC18,24 h) and 10 µg/L (EC41,24 h) cypermethrin, whereas heart activity increased at a concentration of 10 µg/L (EC41,24 h). With regard to azoxystrobin, the activity of all response parameters except the focal spine decreased by exposure to 0.5 mg/L (EC4,24h) azoxystrobin. The focal spine was not affected by azoxystrobin. The results show that physiological mechanisms important for ingestion of food in D. magna may be impaired by low concentrations of commonly used pesticides. Environ. Toxicol. Chem. 2010;29:2371–2378. © 2010 SETAC
Mesoporous Carbon Design for Ionic Liquid‐Based, Double‐Layer Supercapacitors
Authors: Lazzari M. , Soavi F. , Mastragostino M.
Published: July 2010

The use of pyrrolidinium‐based ionic liquids (ILs) in asymmetric electric double‐layer capacitors (AEDLC) with positive and negative carbon electrodes of different weight is a powerful strategy for developing safe, high specific‐energy supercapacitors operating at >3.5 V. The preparation and characterisation of ordered (OTC) and disordered (DTC) template carbons, the latter obtained by a fast and low‐cost method, are reported. The porosity and capacitance features of the template carbons are discussed in view of their application in IL‐based AEDLCs and compared with the properties of aero/cryo/xerogel carbons and a commercial activated carbon. The performance of an N‐butyl‐N‐methyl pyrrolidinium bis(trifluoromethanesulfonyl)imide‐based AEDLC assembled with DTC carbon electrodes operating at 3.9 V featuring high specific energy of 47 Wh kg–1 is then reported. The impact of porosity and surface chemistry of carbons on the electrode capacitive response in IL and on the performance of the IL‐based AEDLC in terms of energy, power and weight distribution of module components is discussed. The effect of IL nature and carbon porosity on the time constant of the double‐layer charging process was also investigated by voltammetric and impedance studies.
Temperature and Humidity Control of a Micro PEM Fuel Cell Stack
Authors: Kunde C. , Hanke‐Rauschenbach R. , Mangold M. , Kienle A. , Sundmacher K. , Wagner S. , Hahn R.
Published: July 2010

This paper deals with the control of a miniaturised fuel cell system. A single air blower is used to control both heat and water management of the fuel cell. As the number of manipulated variables is smaller than the number of control variables, classical control algorithms are not applicable. To find a suitable controller, a system model is developed that shows the qualitatively same behaviour as the experimental setup. The dynamic behaviour of the model and the influence of the blower are studied by phase portraits. A control algorithm is then conceived by qualitative analysis of the phase portraits and tested in simulations.
Sedimentation, cleavage and tectonic thinning in the aberystwyth grits between clarach and wallog, cardigan bay
Authors: Wood Alan
Published: July 2010

In recent years the folding and cleavage seen in the Aberystwyth Grits has been ascribed to downslope movement in soft unlithified sediment, not to tectonic forces. A detailed examination of folded beds in a small part of the outcrop was undertaken to test this theory. It is concluded that the folding and cleavage was initiated by movement from a rising tectonic ridge, but that the sediments may not have been completely lithified at the time of folding.
The impact of manager philosophy on knowledge management systems
Authors: O'Leary Daniel E.
Published: July 2010

This paper analyses how information about managers and technology can be used to provide those managers with a system that is congruent with their needs. In particular, using McGregor's Theories X and Y philosophies, managerial needs are elicited and then contemporary knowledge management technologies, including intelligent agents, and the way they are implemented, are analysed to determine how they meet those manager needs. Different knowledge management technologies are found to be important to manifesting the requirements of particular management philosophies. For example, ‘Theory X’ appears consistent with use of intelligent agents to ‘monitor’ behaviour. This leads to the concept of ‘technology congruence’, where the choice of the technology ultimately is tied to which view of the world the manager employs. Copyright © 2010 John Wiley & Sons, Ltd.
CORPORATE THRIFT AND ECONOMIC GROWTH: A COMPARATIVE STUDY OF DEVELOPING AND DEVELOPED COUNTRIES
Authors: Chen Naiwei
Published: July 2010

This study aims to investigate the relation between corporate saving and economic growth during the period from 1995 to 2006 in 7 developing countries and 16 developed countries. The results show that corporate savings generally add to the economic growth of developing countries regardless of legal origins. On the contrary, corporate savings generally do not contribute to the economic growth of developed countries. Developed countries with common law and Scandinavian civil law legal origins particularly see the negative relation between corporate saving and economic growth, while countries with other legal origins observe no such relation. Copyright © 2010 John Wiley & Sons, Ltd.
Expression of the IP3R1 promoter‐driven nls‐lacZ transgene in Purkinje cell parasagittal arrays of developing mouse cerebellum
Authors: Furutama Daisuke , Morita Noriyuki , Takano Riya , Sekine Yukiko , Sadakata Tetsushi , Shinoda Yo , Hayashi Kanehiro , Mishima Yuriko , Mikoshiba Katsuhiko , Hawkes Richard , Furuichi Teiichi
Published: July 2010

The cerebellar Purkinje cell monolayer is organized into heterogeneous Purkinje cell compartments that have different molecular compositions. Here we describe a transgenic mouse line, 1NM13, that shows heterogeneous transgene expression in parasagittal Purkinje cell arrays. The transgene consists of a nuclear localization signal (nls) fused to the β‐galactosidase (lacZ) composite gene driven by the type 1 inositol 1,4,5‐trisphosphate receptor (IP3R1) gene promoter. IP3R1‐nls‐lacZ transgene expression was detected at a single Purkinje cell level over the surface of a whole‐mount X‐gal‐stained cerebellum because of nuclear accumulation of the nls‐lacZ activity. Developing cerebella of 1NM13 mice showed stripe‐like X‐gal staining patterns of parasagittal Purkinje cell subsets. The X‐gal stripe pattern was likely determined by an intrinsic property as early as E15 and showed increasing complexity with cerebellar development. The X‐gal stripe pattern was reminiscent of, but not identical to, the stripe pattern of zebrin II immunoreactivity. We designated the symmetrical X‐gal‐positive (transgene‐positive, Tg+) Purkinje cell stripes about the midline as vermal Tg1+, Tg2(a, b)+ and Tg3(a, b)+ stripes and hemispheric Tg4(a, b)+, Tg5(a, b)+, Tg6(a, b, c)+, and Tg7(a, b)+ stripes, where a, b, and c indicate substripes. We also assigned three parafloccular substripes Tg8(a, b, c)+. The boundaries of X‐gal stripes at P5 were consistent with raphes in the Purkinje cell layer through which granule cells migrate, suggesting a possible association of the X‐gal stripes with raphe formation. Our results indicate that 1NM13 is a good mouse model with a reproducible and clear marker for the compartmentalization of Purkinje cell arrays. © 2010 Wiley‐Liss, Inc.
Evidence linking solar variability with US hurricanes
Authors: Hodges Robert E. , Elsner James B.
Published: July 2010

The relationship between US hurricanes and solar activity is investigated empirically. First, a relationship between the probability of a US hurricane and the solar cycle is shown conditional on sea surface temperatures (SST). For years of above normal SST, the probability of three or more US hurricanes decreases from 40 to 20% as sunspot numbers (SSN) increase from lower to upper quartile amounts. Second, since SST is in phase with the 11‐year total solar irradiance cycle but upper‐air temperature is in phase with ultraviolet radiation changes on the monthly time scale, an anomaly index of SSN is constructed. The index is significantly correlated with US hurricanes and major US hurricanes over the period 1866‐2008. The chances of at least one hurricane affecting the United States in the lowest and highest SSN anomaly seasons are 68 and 91%, respectively. A similar relationship is noted using hurricane records spanning the period 1749‐1850, providing independent corroborating evidence linking solar variability to the probability of a US hurricane. Copyright © 2010 Royal Meteorological Society
Effects of buckwheat growth on variation of aluminum and major metals in root‐zone soil solutions
Authors: Fu Chen Rong , Fang Shen Ren , Di Yang Xiao , Wang Xianlong
Published: July 2010

The variation in and relationships between aluminum and other major metals including Ca, Mg, Mn, and K in root‐zone soil solutions were studied by growing buckwheat (Fagopyrum esculentum Moench. cv. Jiangxi), an Al accumulator, in pots filled with an acid soil amended with CaCO3 and unamended controls with a preinstalled nondestructive soil‐solution sampler. Soil solutions were collected every 7 d with a syringe connected to the sampler. The results showed that pH of the soil solution was not the only factor controlling the concentration of Al. Significant positive linear correlations were found between Al and Ca as well as between Al and Mg in soil solutions from the controls. The ratio of base cations (BC, Ca+Mg) to Al might partly explain the high Al resistance of buckwheat. Oxalate secretion from roots significantly activated Al in acid soils, which may be important for changes of Al in soil solutions, but it also caused decreased concentrations of Ca, Mg, and Mn. It is concluded that the variation of metal concentrations including Al, Ca, Mg, and Mn is a holistic effect involving competition for exchange sites among Ca, Mg, H, and Al, the chelation by oxalate secreted from roots, and metal uptake by buckwheat.