bluuebunny/crossref_metadata_2025 huggingface dataset:
Identification of an N-Terminal Recognition Site in TLR9 That Contributes to CpG-DNA-Mediated Receptor Activation
Authors: Peter Mirjam E. , Kubarenko Andriy V. , Weber Alexander N. R. , Dalpke Alexander H.
Published: June 2009

Although it is well established that TLR9 recognizes CpG-DNA, the structural details of ligand-receptor interaction are still mostly unknown. The extracellular domain of TLR9 is composed of 25 leucine-rich repeat (LRR) motifs, 5 of which bear inserting sequences that do not conform to the LRR consensus motif. In this study, we show that the functional integrity of the extracellular domain of murine TLR9 is lost by deletion of individual LRR motifs. When deleting only the inserting sequences, we observed that LRR2, 5, and 8 contribute to receptor activation by CpG-DNA. The latter deletions did not affect receptor dimerization but inhibited CpG-DNA binding. On the basis of a homology modeling approach, we furthermore identify a positively charged region in the N terminus that is essential for CpG-DNA-induced TLR9 activation. This interaction site mirrors findings previously shown for the structural recognition of dsRNA by TLR3 and hints toward a general principle of nucleic acid recognition by the respective TLR.
La mort du livre ?
Authors: Chartier Roger
Published: June 2009

Résumé Confronté à la question récurrente de la mort supposée du livre, Roger Chartier se propose de revenir dans cet article 1 sur les raisons qui motivent une telle inquiétude. Pour ce faire, il aborde en historien la double nature du livre et ses implications en droit. Après avoir rappelé l’opposition formulée par Kant entre le bien matériel et le discours , opposition que Fichte réévalue en proposant une nouvelle dichotomie entre les idées et la forme qui leur est donnée à travers l’écriture, Chartier s’arrête sur le discours d’un imprimeur espagnol, Alonso Víctor Paredes, qui au xvii e  siècle, formulait un autre point de vue soucieux de ne pas séparer la matérialité du texte et la textualité du livre. Au regard de cette approche qui ne dissocie pas le texte du livre, il rappelle que notre culture écrite s’est ordonnée, au fil d’une histoire de longue durée, autour d’une relation ternaire établie entre les objets , les catégories de textes et leurs usages . Or le défi de la textualité électronique (de «  la grande conversion numérique  ») n’est-il pas précisément de remettre en cause cet ordre et d’interroger ainsi l’unité du texte à travers la fragmentation de la lecture ?
Genetically Engineered Mouse Models of Ovarian Cancer and Their Utility in Drug Discovery
Authors: Šale Sanja
Published: June 2009

Ovarian cancer is the fourth most common cancer in women and the most lethal gynecological malignancy. The high mortality rate is attributable to the asymptomatic nature of the early stage of the disease, the lack of reliable screening tests, and the development of drug resistance. Approximately 90% of ovarian cancers are thought to originate from the ovarian surface epithelia (OSE). Development of in vivo experimental models that accurately recapitulate genetic events that occur during human epithelial ovarian cancer (EOC) initiation and progression is crucial for a better understanding of EOC pathogenesis, identification of early disease markers, and development of more effective therapy. Historically, one of the most challenging problems in developing genetically engineered mouse models (GEMMs) of EOC has been the lack of tissue‐specific promoters that regulate transgene expression exclusively in adult OSE cells. Recent improvements in gene delivery technology have greatly accelerated development of GEMMs of EOC. This unit describes two distinct methods of transforming OSE cells in GEMMs and the potential applications of these models in oncology drug discovery and development. Curr. Protoc. Pharmacol. 45:14.11.1‐14.11.14. © 2009 by John Wiley & Sons, Inc.
Xenograft and Transgenic Mouse Models of Epithelial Ovarian Cancer and Non‐Invasive Imaging Modalities to Monitor Ovarian Tumor Growth In Situ: Applications in Evaluating Novel Therapeutic Agents
Authors: Connolly Denise C. , Hensley Harvey H.
Published: June 2009

Epithelial ovarian cancer (EOC) is the most commonly fatal gynecologic malignancy in developed countries. Most EOC patients are diagnosed at an advanced stage when disease has spread beyond the ovary. While many patients initially respond to surgery and chemotherapy, the long‐term prognosis is generally unfavorable, with recurrence and development of drug‐resistant disease. There is a critical need to identify new therapeutic agents that prolong disease‐free intervals and effectively manage recurrent disease. Murine models of ovarian carcinoma are excellent models to study tumor biology in the search for new treatments for EOC. Described in this unit are methods for establishing xenograft or allograft models of EOC using ovarian carcinoma cell lines, in vivo imaging strategies for detection and quantification of EOC in transgenic and in xenograft/allograft models, and procedures for necropsy and pathological evaluation of experimental animals. Curr. Protoc. Pharmacol. 45:14.12.1‐14.12.26. © 2009 by John Wiley & Sons, Inc.
Preparation of Short Interfering RNA Containing the Modified Nucleosides 2‐Thiouridine, Pseudouridine, or Dihydrouridine
Authors: Nawrot Barbara , Sochacka Elzbieta
Published: June 2009

Modified uridine derivatives such as 2‐thiouridine (s2U), pseudouridine (Ψ), and dihydrouridine (D) are naturally existing nucleoside units identified in tRNA molecules. Recently, we have shown that such base‐modified units introduced into functionally important sites of siRNA modulate thermodynamic stability of the duplex and its gene silencing activity. In this unit, we describe chemical synthesis of 3′‐phosphoramidite derivatives of s2U and D units (the 3′‐phosphoramidite derivative of Ψ is commercially available), and their use for the synthesis of RNA oligonucleotides according to the routine phosphoramidite protocol. The only exception concerns the oxidation step with I2/pyridine/water which, if applied towards oligonucleotides containing s2U units, would lead to the loss of sulfur. Therefore, to avoid this side reaction, tert‐butyl hydroperoxide is used as an oxidizing reagent. After the oligonucleotide chain assembly is completed, the resulting oligomer is deprotected under mild basic conditions (MeNH2/EtOH/DMSO) to avoid dihydrouracil ring opening, which is a reported side‐reaction during the routine synthesis of dihydrouridine‐containing RNA. Oligonucleotides modified with s2U, D, or Ψ units are useful models for structure‐function studies. Here, the procedure for preparation of siRNA duplexes is described. Curr. Protoc. Nucleic Acid Chem. 37:16.2.1‐16.2.16. © 2009 by John Wiley & Sons, Inc.
RNA Secondary Structure Analysis Using the Vienna RNA Package
Authors: Hofacker Ivo L.
Published: June 2009

This unit documents how to use the Vienna RNA package for RNA secondary structure analysis. Possible tasks include structure prediction for single sequences, prediction of consensus structures, prediction of RNA‐RNA interactions, and sequence design. Curr. Protoc. Bioinform. 26:12.2.1‐12.2.16. © 2009 by John Wiley & Sons, Inc.
Poly(trimethylene carbonate) from Biometals‐Based Initiators/Catalysts: Highly Efficient Immortal Ring‐Opening Polymerization Processes
Authors: Helou Marion , Miserque Olivier , Brusson Jean‐Michel , Carpentier Jean‐François , Guillaume Sophie M.
Published: June 2009

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The ring‐opening polymerization (ROP) of trimethylene carbonate (TMC) was evaluated in bulk at 60–110 °C using various catalyst systems based on bio‐friendly metals, including the metal bis(trimethylsilylamides) Mg[N(SiMe3)2]2, Ca[N(SiMe3)2]2(THF)2, Y[N(SiMe3)2]3, (BDI)Fe[N(SiMe3)2] [BDI=CH(CMeNC6H3‐2,6‐i‐Pr2)2], Fe[N(SiMe3)2]2, Fe[N(SiMe3)2]3, Zn[N(SiMe3)2]2, (BDI)Zn[N(SiMe3)2] and ZnEt2, associated with an alcohol such as isopropyl or benzyl alcohol. The actual metal alkoxide initiating species has been formed in situ prior to the addition of TMC. Introduction of the alcohol component in excess leads to the “immortal” ring‐opening polymerization (ROP) of TMC. According to such an “immortal” ROP process of TMC, whichever the metal species, as many as 200 polycarbonate chains could be successfully grown from a unique metal center in a well controlled ROP process. The best performances were obtained using the discrete (BDI)Zn[N(SiMe3)2] precursor. Under optimized conditions, as many as 50,000 equivalents of TMC could be fully converted from as little as 20 ppm of this metallic precursor, allowing the preparation of a polytrimethylene carbonate (PTMC) with a molar mass as high as 185,200 g mol−1 with a relatively narrow molar mass distribution (Mw/Mn=1.68). A double monomer feed experiment carried out with the (BDI)Zn[N(SiMe3)2]/BnOH initiating system proved the “living” character of the polymerization. Characterization of the PTMCs by NMR and size exclusion chromatography (SEC) showed well‐defined α‐hydroxy‐ω‐alkoxycarbonate telechelic polymers, highlighting the controlled character of this “living and immortal” ROP process. Using the (BDI)Zn[N(SiMe3)2] precursor, varying the alcohol (ROH) to 2‐butanol, 3‐buten‐2‐ol or 4‐(trifluoromethyl)benzyl alcohol, revealed the versatility of this approach, allowing the preparation of accordingly end‐functionalized HO‐PTMC‐OR polymers. The very low initial loading of metal catalyst considerably limits the potential toxicity and thus allows such polycarbonates to be used in the biomedical field.
Hydrosilylation of Ketone and Imine over Poly‐N‐Heterocyclic Carbene Particles
Authors: Tan MeiXuan , Zhang Yugen , Ying Jackie Y.
Published: June 2009

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N‐Heterocyclic carbene (NHC)‐catalyzed ketone/imine hydrosilylation, silane alcohol condensation and asymmetric ketone hydrosilylation reactions were demonstrated for the first time over solid, main‐chain poly‐NHC particles. The stable and robust poly‐NHC particles were easily recovered, and exhibited good catalytic recyclability. A novel chiral induction protocol with a cheap and easily accessible secondary alcohol as the chiral source was also developed in this catalytic system.
Ablative heat transfer in a shrinking packed‐bed of ZnO undergoing solar thermal dissociation
Authors: Schunk L. O. , Lipiński W. , Steinfeld A.
Published: June 2009

A transient heat transfer model is formulated for a shrinking packed‐bed of reacting ZnO particles exposed to concentrated solar irradiation. The model combines conduction, convection, and radiation heat transfer with simultaneous sintering and reaction kinetics. Validation is accomplished in terms of temperatures and dissociation rates experimentally measured using a solar‐driven thermogravimeter with ZnO packed‐bed samples subjected to solar flux concentration ratios in the range 1225–2133 suns and surface temperatures in the range 1834–2109 K. Operating conditions are typical of an ablation regime controlled by the rate of radiative heat transfer to the first layers of ZnO undergoing endothermic dissociation. © 2009 American Institute of Chemical Engineers AIChE J, 2009
Skeletal health: primate model of postmenopausal osteoporosis
Authors: Smith S.Y. , Jolette J. , Turner C.H.
Published: June 2009

Currently, the nonhuman primate is the most widely used large animal model to evaluate the safety and efficacy of new drug entities to treat or prevent estrogen‐deficiency‐induced bone loss and osteoporosis. Surgical ovariectomy (OVX) induces a state of high bone turnover and rapid bone loss establishing a new steady‐state bone mass within 8–9 months. Many systems in the monkey are similar to humans, including skeletal and reproductive physiology and the immune system, making this a plausible model suitable to evaluate the effects of new bone drugs. The long‐term sequelae following OVX and withdrawal of monthly exposure to cyclic reproductive hormones in older female monkeys (cynomolgus and rhesus) mimics estrogen depletion and postmenopausal bone loss occurring in women. Characterization of the primate model revealed an apparent limitation to the extent of bone loss. Animals lose bone mass after OVX, but the extent of the bone loss cannot be described as osteoporotic. The small differences between OVX and sham‐operated controls in many important bone measurements is overcome by including 15–20 animals per group to provide adequate statistical power. The long‐term, at least 16 month, bone safety studies performed to satisfy regulatory guidelines provide an opportunity to study treatment effects for an extended period not covered in shorter‐term safety studies. In vivo end‐points such as densitometry and biochemical markers translate easily to clinical use, while biomechanical end‐points that cannot be measured clinically can be used to predict fracture prevention. To date, the monkey OVX model has been used to support submissions for many new drugs including anabolics, bisphosphonates and selective estrogen receptor modulators. Despite its limitations, the OVX monkey model remains the best characterized of the large animal models of osteopenia and has become integral to osteoporosis drug development. Am. J. Primatol. 71:752–765, 2009. © 2009 Wiley‐Liss, Inc.
Save the dates—CPR's corporate leadership award dinner, and the 2010 Annual Meeting
Authors: Bleemer Russ
Published: June 2009

Dates for the 2009 CPR Institute Corporate Leadership Award Dinner, and next January's Annual Meeting, as well as training information and another look back at this year's Annual Meeting.
Supreme Court lets nonsigners have their arbitration stay say
Authors: Bleemer Russ
Published: June 2009

The last of three U.S. Supreme Court ADR decisions in the current term is handed down, and analyzed. A new professional organization looks at the human brain to learn more about how mediation can be improved. Also, a look at the health care sessions on the first day of the American Bar Association's DR Section annual meeting.
Adapting N‐Heterocyclic Carbene/Azide Coupling Chemistry for Polymer Synthesis: Enabling Access to Aromatic Polytriazenes
Authors: Coady Daniel J. , Khramov Dimitri M. , Norris Brent C. , Tennyson Andrew G. , Bielawski Christopher W.
Published: June 2009

„Klick“ mit ungewohntem Partner: Die Kupplung dimerer N‐heterocyclischer Carbene mit Bisaziden ergibt neuartige konjugierte Polytriazene (siehe Schema). Diese Polymere wurden durch Dotieren elektrisch leitfähig, und Varianten mit Fluorengruppen waren lumineszierend. Die vorgestellte Anwendung belegt das Potenzial von NHCs als Bausteine für Polymere mit nützlichen elektronischen Eigenschaften.

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Sulfonium Boranes for the Selective Capture of Cyanide Ions in Water
Authors: Kim Youngmin , Zhao Haiyan , Gabbaï François P.
Published: June 2009

Fischen nach CN−:Das Sulfonioboran [1]+komplexiert Cyanid in reinem Wasser bei der EU‐weit empfohlenen maximalen Arbeitsplatzkonzentration von 50 ppb. Die hohe Affinität für Cyanidionen ist das Ergebnis günstiger Coulomb‐Effekte im Verbund mit einer direkten bindenden Wechselwirkung zwischen Cyanidionen und Sulfoniogruppen.

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Suprapolymer Structures from Nanostructured Polymer Particles
Authors: Higuchi Takeshi , Tajima Atsunori , Motoyoshi Kiwamu , Yabu Hiroshi , Shimomura Masatsugu
Published: June 2009

Divide and conquer: Polymer nanoparticles with phase‐separation structures prepared with block copolymers and homopolymer blends were used to fabricate unique suprapolymer structures by cross‐linking one polymer moiety and dissolving the other (see scheme; PI=polyisoprene, PSt=polystyrene).

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An [(NHC)(NHCEWG)RuCl2(CHPh)] Complex for the Efficient Formation of Sterically Hindered Olefins by Ring‐Closing Metathesis
Authors: Vorfalt Tim , Leuthäußer Steffen , Plenio Herbert
Published: June 2009

NHC with EWGs for RCM: Ruthenium complexes with two N‐heterocyclic carbenes (NHCs), one of them substituted with electron‐withdrawing groups (EWGs), are highly efficient (pre)catalysts for the synthesis of tetrasubstituted olefins and trisubstituted olefins by ring‐closing metathesis reactions (RCM, see scheme).

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Adapting N‐Heterocyclic Carbene/Azide Coupling Chemistry for Polymer Synthesis: Enabling Access to Aromatic Polytriazenes
Authors: Coady Daniel J. , Khramov Dimitri M. , Norris Brent C. , Tennyson Andrew G. , Bielawski Christopher W.
Published: June 2009

A click by any other name: Coupling bis(N‐heterocyclic carbene)s with bis(azide)s afforded a novel class of conjugated polytriazenes. These polymers were rendered electrically conductive upon doping, and fluorene‐containing variants exhibited luminescence. This adaptation of N‐heterocyclic carbene (NHC)/azide coupling chemistry to polymer synthesis reveals the potential of NHCs as building blocks for accessing polymers having useful electronic properties.

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Sulfonium Boranes for the Selective Capture of Cyanide Ions in Water
Authors: Kim Youngmin , Zhao Haiyan , Gabbaï François P.
Published: June 2009

Going fishing! The sulfonium borane [1]+complexes cyanide in pure water at the maximum allowable concentration of 50 ppb recommended by the European Union. The high cyanide ion affinity displayed by this compound arises from favorable Coulombic effects augmented by a direct bonding interaction between the cyano and sulfonio groups.

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Microemulsions.Background, New Concepts, Applications, Perspectives. Edited by Cosima Stubenrauch.
Authors: Walsh Dominic
Published: June 2009

John Wiley & Sons, Hoboken 2008. 400 pp., hardcover € 129.00.—ISBN 978‐1405167826

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Rheological properties, shear‐dependent electrical resistance, and settling phenomena of polyaniline in ECO solution
Authors: Bhadra Sambhu , Khastgir Dipak
Published: June 2009

Polyaniline (PAni) was synthesized by the miniemulsion polymerization and dispersed in a poly(epichlorohydrine‐co‐ethylene oxide) (ECO) solution. The rheological properties using an R/S Rheometer and the shear‐dependent electrical resistance using a homemade setup were measured. The addition of PAni particles to the ECO solution causes an increase in the shear stress and shear viscosity and the nature of flow changes from a dilatant to a Newtonian fluid. For both the ECO solution and ECO‐PAni mixture, the viscosity at any particular shear rate is higher during the increasing cycle of shear rate compared with the decreasing cycle of shear rate called hysteresis. The ECO‐PAni mixture executes a step‐like viscosity transition over the shear rate region 50–150 s−1, which is known as shear rate‐induced phase transition. The resistance of ECO solution decreases with the increase in shear rate and reversibly increases with the decrease in shear rate, whereas the resistance of ECO‐PAni mixture increases during both the increasing and decreasing cycles of the shear rate. The difference in resistance at zero shear rate before and after the end of shear cycle is termed as electrical set. The ECO solution and ECO‐PAni mixture exhibit 4% and 79% electrical set in terms of decrease and increase of resistance, respectively. The settling process of PAni in the ECO‐PAni mixture is slower compared with the pure ECO in solution. The settling time of PAni in the ECO‐PAni mixture increases with the decrease in shear rate. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Nucleating polymer crystallization with poly(tetrafluoroethylene) nanofibrils
Authors: Bernland Karin , Smith Paul
Published: June 2009

The ability of nanofibrils of poly(tetrafluoroethylene) (PTFE) – in situ generated during compounding – to efficiently nucleate crystal growth of the bulk polymers isotactic polypropylene (i‐PP), high‐density polyethylene (HDPE), polyoxymethylene (POM), polyamide 12 (PA12) and poly(ethylene therephthalate) (PET) is demonstrated. Enhanced nucleation is shown to occur already at PTFE contents as low as 0.001% w/w in i‐PP and HDPE. In addition it was found that compounding with PTFE lead to improved clarity of the latter polymers. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Monodisperse micron‐size polymer core/nanoparticle pigment shell composite particles via heteroaggregation
Authors: Zubitur Manoli M. , Sudol E. David , Dimonie Victoria L. , El‐Aasser Mohamed S.
Published: June 2009

A process for preparing monodisperse, micron‐size composite particles consisting of a polymer core and a nanoparticle pigment shell is described. A heteroaggregation process employing uniform, stable micron‐size polymer particles prepared by dispersion polymerization and unstable carbon black pigment particles proved successful for a variety of polymers including poly(methyl methacrylate) (PMMA), polystyrene (PS), poly(n‐butyl acrylate) (PBuA), and several functional copolymers. Sonication is applied to the mixture enabling the pigment to be broken into its primary particle size, allowing it to form a relatively uniform layer on the surface of the polymer particles by heteroaggregation when the sonication is removed. Attempts to encapsulate these pigment‐coated particles by seeded polymerization resulted in only partial engulfment of the pigment particles in the surface. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Thermally curable adhesive tapes with complex catalyst system for fabricating semiconductor packages
Authors: Saiki Naoya , Nakajima Emi , Shizuhata Hironori , Seno Hideo , Ebe Kazuyoshi
Published: June 2009

Thermal curing of adhesive films was investigated to facilitate the fabrication of a reliable bonding for semiconductors. The formulated adhesive films contained acrylic polymer, epoxy resins, phenol resin, and an imidazole derivative that was the catalyst for curing the epoxy resins with phenol resin. The solubility, thermally latent characteristics, mechanical and adhesive properties of 2‐methylimidazole/boron trifluoride (2MZ/BF3), and 2MZ/aluminum trisacetylacetonate (AlAC) were investigated. It was found that 2MZ/BF3 and 2MZ/AlAC had excellent solubility in adhesive materials and they had excellent latent characteristics as thermal curing catalysts for epoxy resins, whereas conventional catalysts (2MZ and 2‐phenyl‐4, 5‐dihydroxymethylimidazole (2PHZ)) could not achieve both excellent solubility and thermally latent characteristics. The mechanical and adhesive properties of the post‐thermal‐cured adhesive film that contained 2MZ/BF3 or 2MZ/AlAC were comparable to those of the post‐thermal‐cured adhesive films that contained conventional catalysts. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Development of high efficiency particulate absorbing filter materials
Authors: Patanaik Asis , Anandjiwala Rajesh D. , Boguslavsky Lydia
Published: June 2009

We have developed new high efficiency particulate absorbing filter materials by bonding the fiber web with the help of high pressure water jets emerging from micron sized nozzles and subsequently coating the filters with a chemical binder. Two different types of nonwoven filters are produced by varying the water jet pressure during the bonding process. The performance characteristics of the filter materials are evaluated in terms of filtration parameters, such as filtration efficiency, dust holding capacity, and pressure drop. Filtration efficiency depends on the pore characteristics, namely pore size and their distribution in the filters. The developed filter materials have shown promising performance characteristics by capturing higher amount of dust particles with a relatively low pressure drop during use. These filter materials can be used for a wide range of industrial applications, where high filtration efficiency is required at low energy consumption. A fluid flow simulation is carried out by computational fluid dynamics (CFD) to understand flow pattern during the bonding process. The CFD is also used to predict the pressure drop in the nonwoven filter materials during filtration process. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Preparation and properties of bisphenol A‐based sulfonated poly(arylene ether sulfone) proton exchange membranes for direct methanol fuel cell
Authors: Zhang Ni , Li Junjing , Wang Xiangyu , Xia Zhi , Liu Huiling
Published: June 2009

Novel bisphenol A‐based sulfonated poly(arylene ether sulfone) (bi A‐SPAES) copolymers were successfully synthesized via direct copolymerization of disodium 3,3′‐disulfonate‐4,4′‐dichlorodiphenylsulfone, 4,4′‐dichlorodiphenylsulfone, and bisphenol A. The copolymer structure was confirmed by Fourier transform infrared spectra and 1H NMR analysis. The series of sulfonated copolymers based membranes were prepared and evaluated for proton exchange membranes (PEM). The membranes showed good thermal stability and mechanical property. Transmission electron microscopy was used to obtain the microstructures of the synthesized polymers. The membranes exhibit increased water uptake from 8% to 66%, ion exchange capacities from 0.41 to 2.18 meq/g and proton conductivities (25°C) from 0.012 to 0.102 S/cm with the degree of sulfonation increasing. The proton conductivities of bi A‐SPAES‐6 membrane (0.10–0.15 S/cm) with high‐sulfonated degree are higher than that of Nafion 117 membrane (0.095–0.117 S/cm) at all temperatures (20–100°C). Especially, the methanol diffusion coefficients of membranes (1.7 × 10−8 cm2/s–8.5 × 10−7 cm2/s) are much lower than that of Nafion 117 membrane (2.1 × 10−6 cm2/s). The new synthesized copolymer was therefore proposed as a candidate of material for PEM in direct methanol fuel cell. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Morphology and thermal behavior of organo‐bentonite clay/poly(styrene‐co‐methacrylic acid)/poly(isobutyl methacrylate‐co‐4‐vinylpyridine) nanocomposites
Authors: Habi Abderrahmane , Djadoun Said , Grohens Yves
Published: June 2009

Poly(styrene‐co‐methacrylic acid) containing 29 mol % of methacrylic acid (SMA‐29) and poly(isobutyl methacrylate‐co‐4‐vinylpyridine) containing 20 mol % of 4‐vinylpyridine (IBM4VP‐20) were synthesized, characterized, and used to elaborate binary and ternary nanocomposites of different ratios with a 3% by weight hexadecylammonium‐modified bentonite from Maghnia (Algeria) by casting method from tetrahydrofuran (THF) solutions. The morphology and the thermal behavior of these binary and ternary elaborated nanocomposites were investigated by X‐ray diffraction, scanning electron microscopy, FTIR spectroscopy, differential scanning calorimetry, and thermogravimetry. Polymer nanocomposites and nanoblends of different morphologies were obtained. The effect of the organoclay and its dispersion within the blend matrix on the phase behavior of the miscible SMA29/IBM4VP20 blends is discussed. The obtained results showed that increasing the amount of SMA29 in the IBM4VP20/SMA29 blend leads to near exfoliated nanostructure with significantly improved thermal stability. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Quantifying the condition of Hawaiian coral reefs
Authors: Rodgers Ku'ulei S. , Jokiel Paul L. , Bird Christopher E. , Brown Eric K.
Published: June 2009

This investigation developed and tested descriptive models designed to evaluate coral reef ecological condition based on data developed using the basic techniques most often used in coral reef surveys.

Forty‐three variables at 184 stations were analysed in order to identify specific factors that are useful metrics for describing reef condition.

The common practice of using ‘reference sites’ for paired site comparisons was evaluated by developing a reference site model (RSM). This use of reference sites proved to be subjective and unreliable, especially when multiple factors and multiple sites are involved. However, in some cases the RSM is appropriate in demonstrating severe degradation based on factors such as sediment, coral cover and fish abundance.

An objective ecological gradient model (EGM) was developed based on a wide range of metrics at numerous sites. A computer program was developed that allows a quantitative ranking of reef condition along a continuum and can be used to compare reefs across a wide range of conditions. Further, this approach permits the operator to alter and define criteria appropriate to a specific question.

Results of this investigation provide ecological insights into the importance of natural and anthropogenic ecological factors in determining coral reef condition. Copyright © 2009 John Wiley & Sons, Ltd.
Spatial abilities in an elective course of applied anatomy after a problem‐based learning curriculum
Authors: Langlois Jean , Wells George A. , Lecourtois Marc , Bergeron Germain , Yetisir Elizabeth , Martin Marcel
Published: June 2009

A concern on the level of anatomy knowledge reached after a problem‐based learning curriculum has been documented in the literature. Spatial anatomy, arguably the highest level in anatomy knowledge, has been related to spatial abilities. Our first objective was to test the hypothesis that residents are interested in a course of applied anatomy after a problem‐based learning curriculum. Our second objective was to test the hypothesis that the interest of residents is driven by innate higher spatial abilities. Fifty‐nine residents were invited to take an elective applied anatomy course in a prospective study. Spatial abilities were measured with a redrawn Vandenberg and Kuse Mental Rotations Test in two (MRT A) and three (MRT C) dimensions. A need for a greater knowledge in anatomy was expressed by 25 residents after a problem‐based learning curriculum. MRT A and C scores obtained by those choosing (n = 25) and not choosing (n = 34) applied anatomy was not different (P = 0.46 and P = 0.38, respectively). Percentage of residents in each residency program choosing applied anatomy was different [23 vs. 31 vs. 100 vs. 100% in Family Medicine, Internal Medicine, Surgery, and Anesthesia, respectively; P < 0.0001]. The interest of residents in applied anatomy was not driven by innate higher spatial abilities. Our applied anatomy course was chosen by many residents because of training needs rather than innate spatial abilities. Future research will need to assess the relationship of individual differences in spatial abilities to learning spatial anatomy. Anat Sci Ed 2:107–112, 2009. © 2009 American Association of Anatomists.
Uncertainties in future projections of extreme precipitation in the Indian monsoon region
Authors: Turner A. G. , Slingo J. M.
Published: June 2009

Uncertainties in changes to the spatial distribution and magnitude of the heaviest extremes of daily monsoon rainfall over India are assessed in the doubled CO2 climate change scenarios in the IPCC Fourth Assessment Report. Results show diverse changes to the spatial pattern of the 95th and 99th subseasonal percentiles, which are strongly tied to the mean precipitation change during boreal summer. In some models, the projected increase in heaviest rainfall over India at CO2 doubling is entirely predictable based upon the surface warming and the Clausius–Clapeyron relation, a result which may depend upon the choice of convection scheme. Copyright © 2009 Royal Meteorological Society and Crown Copyright
Simultaneous quantification of five major constituents in stems of Dracaena plants and related medicinal preparations from China and Vietnam by HPLC–DAD
Authors: Fan Lan‐Lan , Tu Peng‐Fei , Chen Hu‐Biao , Cai Shao‐Qing
Published: June 2009

A high‐performance liquid chromatographic (HPLC) method was developed for the simultaneous quantification of five major bioactive constituents in the stems of resiniferous Dracaena plants from China and Vietnam, as well as those in the related traditional Chinese medicinal preparations. A diode array detector with the wavelength of 330 nm was used to monitor resveratrol, 7,4′‐dihydroxyflavone and pterostilbene, while loureirin A and loureirin B were monitored at 280 nm. The five constituents were separated on an Agela SB C18 column by gradient elution using 0.008% (v/v) formic acid solution (A) and acetonitrile (B) as the mobile phase. The validation of the method included recovery, linearity, accuracy and precision (intra‐ and inter‐day variation). The range of recoveries of this method was 98.1–104.9%, with all the constituents showing good linearity (r2 > 0.9999). The accuracy and precision were satisfactory, with the overall intra‐ and inter‐day variation being less than 4%. The present method has been successfully applied for the determination of all five constituents in 21 related herbal samples including 10 D. cochinchinensis stem samples, seven D. cambodiana stem samples and four purchased medicinal preparations. The contents of these constituents were analyzed using principal component analysis, which can efficiently identify raw herb of Dracaena from different sources. The study may be considered helpful to the quality control of Dracena plants and its medicinal preparations. Copyright © 2009 John Wiley & Sons, Ltd.
Tailored carbon nanotubes for tissue engineering applications
Authors: Veetil Jithesh V. , Ye Kaiming
Published: June 2009

A decade of aggressive researches on carbon nanotubes (CNTs) has paved way for extending these unique nanomaterials into a wide range of applications. In the relatively new arena of nanobiotechnology, a vast majority of applications are based on CNTs, ranging from miniaturized biosensors to organ regeneration. Nevertheless, the complexity of biological systems poses a significant challenge in developing CNT‐based tissue engineering applications. This review focuses on the recent developments of CNT‐based tissue engineering, where the interaction between living cells/tissues and the nanotubes have been transformed into a variety of novel techniques. This integration has already resulted in a revaluation of tissue engineering and organ regeneration techniques. Some of the new treatments that were not possible previously become reachable now. Because of the advent of surface chemistry, the CNT's biocompatibility has been significantly improved, making it possible to serve as tissue scaffolding materials to enhance the organ regeneration. The superior mechanic strength and chemical inert also makes it ideal for blood compatible applications, especially for cardiopulmonary bypass surgery. The applications of CNTs in these cardiovascular surgeries led to a remarkable improvement in mechanical strength of implanted catheters and reduced thrombogenecity after surgery. Moreover, the functionalized CNTs have been extensively explored for in vivo targeted drug or gene delivery, which could potentially improve the efficiency of many cancer treatments. However, just like other nanomaterials, the cytotoxicity of CNTs has not been well established. Hence, more extensive cytotoxic studies are warranted while converting the hydrophobic CNTs into biocompatible nanomaterials. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009
Direct measurement of the kinetics of CBM9 fusion‐tag bioprocessing using luminescence resonance energy transfer
Authors: Kavoosi Mojgan , Creagh A. Louise , Turner Robin F. B. , Kilburn Douglas G. , Haynes Charles A.
Published: June 2009

The economics of affinity‐tagging technologies, particularly at preparative scales, depends in part on the cost and efficiency of the bioprocessing step used to remove the affinity tag and obtain the final purified product (Lowe et al., J Biochem Biophys Methods. 2001;49:561–574). When CBM9, the family 9 cellulose binding module from Thermotoga maritima, serves as the affinity tag, the overall efficiency of tag removal is a function of the choice of processing enzyme and the local structure of the cleavage site, most notably the linker sequence flanking the bioprocessing recognition site on the tag side. A novel spectroscopic method is reported and used to rapidly and accurately measure CBM9 fusion‐tag bioprocessing kinetics and their dependence on the choice of linker sequence. The assay monitors energy transfer between a lanthanide‐based donor bound to the CBM9 tag and an acceptor fluorophore presented on the target protein or peptide. Enzyme‐catalyzed cleavage of the fusion tag terminates this resonance energy transfer, resulting in a change in fluorescence intensity that can be monitored to quantify substrate concentration over time. The assay is simple, fast and accurate, providing kcat/KM values that contain standard errors of less than 3%. As a result, both substantial and subtle differences in bioprocessing kinetics can be measured and used to guide bioproduct design. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009
N‐way morphing for 2D animation
Authors: Baxter William , Barla Pascal , Anjyo Ken
Published: June 2009

We present a novel approach to the creation of varied animations from a small set of simple 2D input shapes. Instead of providing a new 2D shape for each keyframe of an animation sequence, we interpolate between a few example shapes in a reduced pose‐space. Similar approaches have been presented in the past, but were restricted in the types of input or range of deformations allowed. In order to address these limitations, we reformulate the problem as an N‐way morphing process on 2D input bitmap or vector graphics. Our formulation includes an N‐way mapping technique, an efficient, rigidity preserving nonlinear blending function, improved extrapolation and a novel scattered data interpolation technique to manage the reduced pose‐space. The resulting animations are correlated to paths in the reduced pose‐space, allowing users to intuitively and interactively control temporal behaviours with simple gestures. We demonstrate our techniques in several example animations. Copyright © 2009 John Wiley & Sons, Ltd.
Analysis of Protein–Protein Interactions by Using Droplet‐Based Microfluidics
Authors: Srisa‐Art Monpichar , Kang Dong‐Ku , Hong Jongin , Park Hyun , Leatherbarrow Robin J. , Edel Joshua B. , Chang Soo‐Ik , deMello Andrew J.
Published: June 2009

Every little drop: The KD values of angiogenin (ANG) interactions as shown by FRET analysis of thousands of pL‐sized droplets agree with data from bulk‐fluorescence polarization measurements. Importantly, the use of fluorophores does not affect the activity of ANG or the binding of anti‐ANG antibodies to ANG. Such an experimental platform could be applied to the high‐throughput analysis of protein–protein interactions.

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Epoxide‐Hydrolase‐Initiated Hydrolysis/Rearrangement Cascade of a Methylene‐Interrupted Bis‐Epoxide Yields Chiral THF Moieties without Involvement of a “Cyclase”
Authors: Ueberbacher Barbara T. , Oberdorfer Gustav , Gruber Karl , Faber Kurt
Published: June 2009

Cyclase‐free at last: A methylene‐interrupted meso‐bis‐epoxide was stereoselectively converted into dihydroxy‐tetrahydrofuran derivatives with excellent de and ee values through an enzyme‐triggered nucleophilic hydrolysis/cyclisation cascade. Molecular modelling showed that the point of enzyme attack was determined by the stereospecificity of the epoxide hydrolase, whereas the stereochemical course of the cyclisation step was solely governed by Baldwin's rules and did not invoke the involvement of a “cyclase”.

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In contrast with electrophilic enzyme‐catalysed cyclisations in terpenoid biosynthesis, cyclisations of tetrahydrofuran moieties found in several groups of natural products, such as annonaceous acetogenins, neurofurans and phytooxylipins, appear to proceed through a nucleophilic cascade mechanism starting from bis‐epoxy fatty acid precursors. This hypothesis was verified by epoxide‐hydrolase‐catalysed hydrolytic ring‐opening/cyclisation cascades starting from a methylene‐interrupted meso‐bis‐epoxide model substrate, which furnished the corresponding THF products with excellent de and ee values. Molecular modelling showed that the points of enzyme attack were consistent with the stereospecificities of the enzymes, whereas the stereochemical courses of the cyclisation were solely governed by Baldwin's rules and did not invoke the involvements of a “cyclase”.
Synthesis of enantiomers ofexo‐2‐norbornyl‐N‐n‐butylcarbamate andendo‐2‐norbornyl‐N‐n‐butylcarbamate for stereoselective inhibition of acetylcholinesterase
Authors: Chiou Shyh‐Ying , Huang Chuan‐Fu , Yeh Shyh‐Jei , Chen I‐Ru , Lin Gialih
Published: June 2009

The acetylcholinesterase inhibition by enantiomers ofexo‐ andendo‐2‐norbornyl‐N‐n‐butylcarbamates shows high stereoselelectivity. For the acetylcholinesterase inhibitions by (R)‐(+)‐ and (S)‐(−)‐exo‐2‐norbornyl‐N‐n‐butylcarbamates, theR‐enantiomer is more potent than theS‐enantiomer. But, for the acetylcholinesterase inhibitions by (R)‐(+)‐ and (S)‐(−)‐endo‐2‐norbornyl‐N‐n‐butylcarbamates, theS‐enantiomer is more potent than theR‐enantiomer. Optically pure (R)‐(+)‐exo‐,(S)‐(−)‐exo‐, (R)‐(+)‐endo‐, and (S)‐(−)‐endo‐2‐norbornyl‐N‐n‐butylcarbamates are synthesized from condensations of optically pure (R)‐(+)‐exo‐,(S)‐(−)‐exo‐, (R)‐(+)‐endo‐, and (S)‐(−)‐endo‐2‐norborneols withn‐butyl isocyanate, respectively. Optically pure norborneols are obtained from kinetic resolutions of their racemic esters by lipase catalysis in organic solvent. Chirality 2010. © 2009 Wiley‐Liss, Inc.
Optische Extinktionsmessverfahren zur Inline‐Kontrolle disperser Stoffsysteme
Authors: Steinke L. , Wessely B. , Ripperger S.
Published: June 2009

Optische Messverfahren besitzen neben der vielseitigen Einsetzbarkeit den Vorteil, dass sie berührungslos und rückwirkungsfrei Stoffsysteme vermessen können. Sie werden häufig zur Partikelanalyse eingesetzt und sind in diesem Zusammenhang auch für die Überwachung von Prozessen interessant, bei denen disperse Stoffsysteme erzeugt, verändert oder separiert werden. Im Folgenden werden die Grundlagen der optischen Extinktionsmesstechnik zur Partikelanalyse beschrieben und Messsysteme vorgestellt, die es erlauben, mehrere Zustandsgrößen eines Partikelsystems aufgrund der Extinktionsmessung zu erfassen.
Stofftransportprozesse in Blasensäulen und Stabilisierung von organischen Nanopartikeln mit verschiedenen Tensiden
Authors: Hermeling M. , Weber A. P.
Published: June 2009

Untersucht wurde der Transport gasgetragener Partikel in unterschiedliche Tensidlösungen in einer Einzelblasenkammer. Insbesondere wurde der Einfluss der sich oberhalb der Flüssigkeit ausbildenden Schaumschicht charakterisiert, die im Wesentlichen die Partikelkonzentration in der Suspension erhöht. Zudem hat die Wahl des Tensids einen signifikanten Einfluss auf die Partikelkonzentration in der Suspension.
Impaktion und Abspringen von Nanopartikel‐Agglomeraten bei der Trockendispergierung
Authors: Wu T. , Weber A. P.
Published: June 2009

Um die größenabhängigen Eigenschaften von Nanopartikeln zu nutzen, kann eine Trockendispergierung hilfreich sein. In der vorliegenden Arbeit wurde die Trockendispergierung von industriellen Aerosil®‐Nanopulvern untersucht. Dabei zeigte sich, dass eine Vielzahl von Prozessen parallel abläuft, die zum Teil als Informationsquelle zu den einzelnen Schritten der Trockendispergierung verwendet werden können.
Verbesserung der Fließfähigkeit feiner kohäsiver Pulver durch nanoskalige Fließhilfsmittel
Authors: Kleinschmidt S. , Tomas J.
Published: June 2009

Die überwiegende Zahl mineralischer Rohstoffe und Konzentrate, Hilfsstoffe, landwirtschaftlicher und synthetischer disperser Feststoffprodukte wird in Partikelgrößen kleiner als 100 μm erzeugt. Diese feinen Pulver weisen eine Reihe recht problematischer Produkteigenschaften auf. Ihre interpartikulären Haftkräfte, insbesondere die Van‐der‐Waals‐Kräfte, übersteigen die Gewichtskräfte um mehrere Größenordnungen. Die störungsfreie Handhabung dieser Produkte stellt daher ein großes Problem und eine wissenschaftlich‐technische Herausforderung dar. Ihre physikalischen Eigenschaften, insbesondere die Fließfähigkeit, sind jedoch für viele Industriezweige der Erzeugung, Weiterverarbeitung, Anwendung und des Verbrauchs, beispielsweise in der Pharmaindustrie, Lebensmittelindustrie, chemischen Industrie oder im Maschinen‐ und Anlagenbau, besonders bedeutsam. Eine seit Jahrzehnten häufig praktizierte Lösungsmöglichkeit besteht im Zusatz geringer Mengen sogenannter Fließhilfsmitteln, die die Fließfähigkeit feiner kohäsiver Pulver deutlich verbessern sollen. Diese Publikation gibt eine Übersicht über die physikalisch‐chemischen Wirkprinzipien der Fließhilfsmittel, die beschreibenden Modellvorstellungen und die einschlägigen Bewertungsmethoden der Fließfähigkeit. Anhand einiger typischer Messreihen aus der Literatur werden die Wirksamkeit der Zugabe von Nanopartikeln und Tensiden kritisch diskutiert und Schlussfolgerungen für deren verfahrenstechnische Anwendbarkeit gezogen.
Reaction accompanied mass transfer from fluid and solid spheres at low reynolds numbers
Authors: Johnson A. I. , Akehata T.
Published: June 2009

Reaction accompanied mass transfer from fluid and solid spheres has been studied for creeping flow and a first order reaction.

The results are presented graphically as Sherwood number plotted against Peclet number, with a dimensionless reaction rate factor as a parameter. At high values of the Peclet number the results approach the curves for physical mass transfer, while at low Peclet numbers the results may be predicted by the equations for reaction accompanied diffusions.

The results were obtained by Yuge's method and by finite‐difference numerical methods. The latter methods had limited ranges of applicability.
The dynamics of reactors of mixed type: I. The nature of the steady state
Authors: Gall C. E. , Aris R.
Published: June 2009

The steady state of a reactor consisting of a tubular reactor followed by a stirred tank with material and thermal feedback is invesigated here. It is found that the overall heat generation curve can be considerably more complex than that of a single stirred tank on account of the backmixing and feedback. The influence of these effects on the stability of the reactor is discussed.
Operating lines in cascade separation of binary mixtures
Authors: Hwang S‐T. , Kammermeyer Karl
Published: June 2009

The general case of cascade operation is treated without any restriction on the value of the separation factor. Equilibrium curves are briefly discussed. These are generally a function of the cut.

The equations of operating lines for both of enriching and stripping sections are derived for the general case by appropriate material balances. Also, three specific applications are presented in detail, by showing graphical constructions and discussing characteristic features for each case.
Hydrates in the methane‐nitrogen system
Authors: Jhaveri Jaysukh , Robinson Donald B.
Published: June 2009

The gas hydrate equilibrium curves for systems containing methane and nitrogen have been obtained in the temperature interval 32°F. to 72°F. and between pressures of 350 and 5100 Ib./sq.in.abs. The composition of the equilibrium gas and hydrate phases was determined experimentally at 32°F. and 44°F. This information was used to calculate vapor‐solid equilibrium ratios for both nitrogen and methane. A comparison is made between the equilibrium ratios in this system which crystallizes in Structure I and the ratios in systems reported earlier which crystallize in Structure II.
The prediction of binary adsorption equilibria from pure component isotherms
Authors: Cook W. H. , Basmadjian D.
Published: June 2009

A semi‐empirical method is proposed for the prediction of adsorption equilibria of binary gas mixtures from pure component isotherms, including and extending beyond the range of validity of previous methods. It is based on an expression, derived earlier by one of the authors(1) which relates the binary separation factor α to the pure component pressure ratio at constant volume adsorbed.

The method permits the quantitative calculation of the binary isotherms, V1 = f1 (p1) and V2 = f2 (p2), in the entire range of mono‐molecular adsorption, and yields predicted values in good agreement with experimental data for a variety of systems in the range 75°‐363°K and total pressures up to 35 atm.
Prediction of vapor‐liquid equilibrium data of binary systems
Authors: Nagata Isamu
Published: June 2009

This paper presents a method of predicting vapor‐liquid equilibria of binary systems at reduced or higher pressures if vapor‐liquid equilibria of the systems concerned are available at atmospheric pressure. The method is based upon Prahl's three‐constant equation which expresses vapor‐liquid composition relationships directly. Experimental data and those calculated by the proposed method are compared for five typical nonideal binary systems.