bluuebunny/crossref_metadata_2025 huggingface dataset:
Preparation and high oxygen‐enriching properties of cross‐linking polydimethylsiloxane/SiO2 nanocomposite membranes for air purification
Authors: Rao Huaxin , Zhang Ziyong , Tian Ye
Published: May 2012

Nanocomposite membrane based on polydimethylsiloxane (PDMS) and nanoscale SiO2 particles were prepared by a convenient and mild sol–gel copolymerization of tetraethoxysilane as well as cross‐linking reaction. The oxygen‐enriching properties of cross‐linking PDMS/SiO2 nanocomposite membranes containing different silica conversion and SiO2 contents were investigated. The results showed that the nanocomposite membranes exhibited good membrane‐forming ability, superior mechanical properties, and high solvent resistance as well as excellent oxygen‐enriching properties for air purification. The oxygen‐enriching performance was regulated by the organic/inorganic ratio and silica conversion in the sol–gel synthesis process. Permeability and selectivity could increase simultaneously with the addition of nanoscale SiO2. The oxygen permeation coefficient of the nanocomposite membrane increased to 680 Barrer and oxygen/nitrogen separation factor kept 3.0 or so, both higher than those of the corresponding pure PDMS membrane. The high oxygen‐enriching properties of the nanocomposite membranes arose from the introduction of SiO2 particles, the sol–gel copolymerization, and cross‐linking method. © 2012 American Institute of Chemical Engineers AIChE J, 59: 650–655, 2013
Optimisation of solid liquid extraction of jatropha oil using petroleum ether
Authors: Sayyar Sepidar , Abidin Zurina Zainal , Yunus Robiah
Published: May 2012

Jatropha curcas I. is an oil‐bearing seed plant with a wide range of applications. The oil from the seeds of this plant has been used as an industrial raw material for many years. One of the important characteristics of jatropha oil is its potential for fuel and biodiesel production to meet the global energy demand. In this paper, solid–liquid extraction of jatropha oil from seeds using petroleum ether was optimised on the basis of the amount of the extracted oil. Four main factors, namely temperature, the solvent‐to‐solid ratio, the reaction time and the size of the raw material, were investigated to optimise extraction conditions for achieving the highest oil yield under experimental conditions. The kinetics of the extraction using petroleum ether as the solvent were also studied and fitted to a second‐order model. The free fatty acid (FFA) content of the oil was used as an index of the oil quality. The optimum conditions were found to be 7 h of reaction time, a temperature of 68 °C, a coarse particle size of 0.5–0.75 mm and a solvent‐to‐solid ratio of 6 : 1. Storing the ground seeds for one week before extraction had a remarkably negative effect on the quality of the oil produced (FFA ≈ 6.99%), whereas the quality of the oil was satisfactory when extracted from the seeds immediately after grinding (FFA ≈ 0.62%). The experimental data fitted well to the second‐order model with the saturation extraction capacity and the initial extraction rate increasing with increasing temperature. Copyright © 2012 Curtin University of Technology and John Wiley & Sons, Ltd.
Effect of processing techniques on the performance of Epoxy/MWCNT nanocomposites
Authors: Hosur Mahesh , Barua Rajib , Zainuddin Shaik , Kumar Ashok , Trovillion Jonathan , Jeelani Shaik
Published: May 2012

The aim of this study is to investigate the optimum technique to disperse Multi‐Walled Carbon Nanotubes (MWCNTs) in SC‐1 epoxy uniformly and to evaluate the effect of processing technique on the performance of SC‐1 epoxy. To achieve better dispersion, MWCNT was mixed with SC‐1 resin directly or premixed with a solvent and then mixed with SC‐1 resin after evaporating the solvent using sonication, thinky mixing and three‐roll mill methods either in isolation or combination. Flexural tests were performed to evaluate mechanical performances and results exhibit up to 27.13, 13.51, and 21.99% improvement on flexural strength, flexural modulus, and maximum strain, respectively, over neat epoxy with only 0.2 wt % loading. Dynamic mechanical analysis (DMA), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) indicated improvement in storage modulus, Tg, inflection temperature, and residue content, respectively over neat SC‐1 epoxy. Thermal and mechanical properties at higher loading conditions were seen to either reduce or not significantly improve. This was attributed to high viscosity of nanocomposites as determined by rheological analysis which prevents good dispersion of MWNCTs into epoxy system at 0.4 wt % loading. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Preparation and characterization of electromagnetic interference shielding polyimide foam
Authors: Liu Xiao‐Yan , Zhan Mao‐Sheng , Wang Kai
Published: May 2012

This article focused on the preparation and characterization of ultralight and high‐temperature resistant polyimide foam (PIF) for electromagnetic interference shielding. PIF was first prepared based on a one‐pot process by the primary reactions of derivatives of pyromellitic dianhydride and polyaryl polymethylene isocyanate. Then, PIFs with silver (0) coating were then prepared by spraying silver (0) on the surfaces of PIF through physical spraying method. The surface density of silver coating was 0.18 kg/m2, and the densities of silver‐coated PIFs were less than 23 kg/m3. The scanning electron microscopy coupled with an energy‐dispersive X‐ray spectrometer (EDX) measurement were carried out to investigate the morphological and chemical properties of uncoated and coated PIFs. For coated PIFs, the EDX spectrums indicated increasing higher silver proportions from interior to exterior surface, together with increasing higher carbon proportions from exterior surface to interior. Thermogravimetry/Fourier transform infrared instrument that combined thermogravimetric analysis with pyrolysis product analysis by Fourier transform infrared spectroscopy were applied to investigate the thermal stability and pyrolysis products of uncoated and coated PIFs. The results indicated that the thermal properties of silver‐coated PIFs were improved obviously with the 5% weight loss temperature higher than 400°C and the residual weight retentions at 800°C ∼ 80%. In the frequency range 200–7000 MHz, the EMI shielding efficiency with one surface and two surfaces coated with silver were in the range of 36.4–60.7 dB and 61.6–95.6 dB, respectively. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Immobilization of Candida lipolytica lipase on macroporous beaded terpolymers with epoxy groups
Authors: Liu Wentao , Duan Hongdong , Meng Xia , Qin Dawei , Wang Xingjian , Zhang Juan
Published: May 2012

A series of macroporous beaded terpolymers with epoxy groups were synthesized by suspension polymerization with glycidyl methacrylate (GMA), ethylene glycol dimethacrylate (EGDMA), and the third monomers including styrene, methyl methacrylate, n‐butyl acrylate (BA), butyl methacrylate (BMA), and 2‐hydroxyethyl methacrylate for immobilization of Candida lipolytica lipase. The effect of various third monomers on loading and activity recovery of immobilized lipase were studied. Terpolymers with BA as the third monomer were found to give the biggest loading of lipase, and the activity recovery of lipase immobilized on poly(GMA‐EGDMA‐BA) terpolymers reached 79.0%. As the content of BA (%) increasing, the loading of lipase enhanced, but the activity recovery reached 88.5% for the initial stage and decreased to 46.9% at last. The poly(GMA‐EGDMA‐BA‐10) showed an optimal result in lipase immobilization. Lipase immobilized on poly(GMA‐EGDMA‐BA‐10) carriers had broader pH and higher temperature stability. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
The effect of γ‐Irradiation and reactive extrusion on the structure and properties of polycarbonate and starch blends: A work oriented to the recycling of thermoplastic wastes
Authors: Vignon Anaïs , Ayoub Ali , Massardier Valérie
Published: May 2012

Polymer materials with improved properties can be obtained through polymer blends. As a polymer mixture is generally immiscible and incompatible, it is necessary to develop new methods to improve the interfacial adhesion. In this study, polycarbonate‐based extruded thermoplastic were developed by blending polycarbonate with thermoplastic starch using extensive process engineering based on structure–property correlations. Starch was destructurized and plasticized followed by melt‐blending with polycarbonate. The optimal conditions for processing of the thermoplastics blends were found to be 230°C, 2 min of processing time, and 3–6 wt % of glycerol. The effect of γ‐irradiation on the fabrication of the blend was studied. Changes in structure, morphology, and properties resulting from γ‐exposure in the range 0–150 kGy were investigated. Electron spin resonance results revealed that numerous radicals remained trapped in the materials after irradiation even after a long time enabling reactions between starch and polycarbonate. Results obtained from tensile test, differential scanning calorimetry, and dynamic mechanical analysis revealed the relatively good affinity between the two components after blending in a micro‐extruder. Irradiated blends are thermally more stable than those non‐irradiated. Mechanical tests also showed that the efficiency of the irradiation depended greatly on the dose applied to the initial materials. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Influence of laminate thickness reduction on the deformation mechanism of coextruded multilayered PC/PMMA films
Authors: Scholtyssek Stefanie , Seydewitz Volker , Adhikari Rameshwar , Pfeifer Frank , Michler Goerg Hannes , Siesler Heinz Wilhelm
Published: May 2012

The influence of the morphology of multilayered composites of poly(methyl‐methacrylate) (PMMA) and polycarbonate (PC) fabricated by layer multiplying coextrusion technique on their mechanical and especially their micromechanical deformation behavior was investigated. Electron microscopic studies revealed that the PC/PMMA multilayered composites have a well‐oriented, uniform, and continuous layered architecture. With decreasing layer thickness of each polymer in the composite, the elongation at break of the films was found to increase significantly which was correlated with a transition from a two‐component behavior (for single‐layer thickness of ≥8 μm) to an one‐component behavior (for single‐layer thickness of ≤250 nm). Rheo‐optical measurements using FTIR spectroscopy revealed that the molecular orientation during stretching of the PMMA phase remains unchanged for all the investigated films, whereas the PC orientation function decreases with decreasing layer thickness. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Development of high Tg epoxy resin and mechanical properties of its fiber‐reinforced composites
Authors: Yi Jin‐Woo , Um Moon‐Kwang , Byun Joon‐Hyung , Lee Sang‐Bok , Lee Sang‐Kwan
Published: May 2012

A new epoxy resin with high glass transition temperature (Tg) (∼ 180°C) and a viscosity low enough for infiltration into dry reinforcements at 40°C was developed for the vacuum‐assisted resin transfer molding process. To study the curing behavior and viscosity, several blends were formulated using multifunctional resin, aromatic hardener, and reactive diluents. Effects of these components on the viscosity and Tg were investigated by thermomechanical analysis, dynamic scanning calorimetry, and rheometer. Experimental results showed that a liquid aromatic hardener and multifunctional epoxy resin should be used to decrease the viscosity to <1 Pa·s at 40°C. Moreover, the addition of a proper reactive diluent decreased the viscosity and simultaneously minimized the deterioration of Tg. Mechanical properties of the composite produced with the optimized blend were evaluated at both room‐temperature and high‐temperature conditions. According to the results, the composite showed comparable mechanical properties with that of the current commercial resin. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Lack of Tir Ubiquitylation Contributes to Enteropathogenic E. coli Remaining Extracellular During Nonphagocytic Cell Infections
Authors: Lin Ann E. , Guttman Julian A.
Published: May 2012

Enteropathogenic Escherichia coli (EPEC) is an extracellular pathogen that alters many host subcellular components during its infectious processes. We have previously shown that EPEC hijacks a large assortment of host cell endocytic components and uses these proteins to form protruding structures called “pedestals” rather than triggering internalization of the bacteria. Other invasive pathogens that also recruit similar endocytic components have been shown to enter their host cells on the ubiquitylation of their host cell receptors. Therefore, we hypothesize that EPEC remains extracellular by maintaining its receptor, translocated intimin receptor (Tir), in an unubiquitylated state. Using immunoprecipitation‐Western blots, we demonstrate no association of ubiquitin with Tir. To further elucidate the effect Tir ubiquitylation would have on EPEC during their infections, we engineered Tir‐ubiquitin fusion constructs, expressed them in host epithelial cells, and infected them with Δtir EPEC. We found these cells induced a significant increase in EPEC invasion as compared with cells that expressed the Tir construct that lacked ubiquitin conjugation. Our results indicate that the lack of EPEC receptor ubiquitylation is a contributing factor that these microbes use to prevent their internalization into epithelial cells. Anat Rec, 2012. © 2012 Wiley Periodicals, Inc.
Scholarly network similarities: How bibliographic coupling networks, citation networks, cocitation networks, topical networks, coauthorship networks, and coword networks relate to each other
Authors: Yan Erjia , Ding Ying
Published: May 2012

This study explores the similarity among six types of scholarly networks aggregated at the institution level, including bibliographic coupling networks, citation networks, cocitation networks, topical networks, coauthorship networks, and coword networks. Cosine distance is chosen to measure the similarities among the six networks. The authors found that topical networks and coauthorship networks have the lowest similarity; cocitation networks and citation networks have high similarity; bibliographic coupling networks and cocitation networks have high similarity; and coword networks and topical networks have high similarity. In addition, through multidimensional scaling, two dimensions can be identified among the six networks: Dimension 1 can be interpreted as citation‐based versus noncitation‐based, and Dimension 2 can be interpreted as social versus cognitive. The authors recommend the use of hybrid or heterogeneous networks to study research interaction and scholarly communications.
Intramolecular [2+2] Photocycloaddition Reactions as an Entry to the 2‐Oxatricyclo[4.2.1.04, 9]nonan‐3‐one Skeleton of Lactiflorin
Authors: Lu Ping , Herdtweck Eberhardt , Bach Thorsten
Published: May 2012

Two [2+2] photocycloaddition routes were evaluated as possible ways to access the tricyclic core structure found in the terpene monoglycoside lactiflorin. While the first route via γ‐substituted cyclopentenones was quickly discarded, the reactions of racemic (5R*)‐3‐benzyloxy‐5‐but‐3′‐enyl‐4‐methoxycarbonylfuran‐2(5 H)‐ones proceeded in high yields and with perfect diastereoselectivity. However, it turned out that the regioselectivity was strongly dependent on the substitution pattern within the but‐3′‐enyl chain, which connects the terminal olefinic double bond to the photoexcited butenolide chromophor. If the chain was unsubstituted or if a tert‐butyldimethylsilyloxy group was placed at the 2′ position in a syn‐relationship to the existing stereogenic center (5R*,2′S*), the crossed product prevailed with regioselectivities of 89:11 to 69:31. If the tert‐butyldimethylsilyloxy group was positioned at 2′ in an anti‐relationship to the existing stereogenic center (5R*,2′R*), the desired straight products were obtained in regioselectivities of 74:24 to 55:45 (61–83 % yield). Following this route, the aglycon part of lactiflorin was obtained by an intramolecular [2+2] photocycloaddition and a subsequent hydrogenolysis in 53 % yield. Its further conversion into the natural product after glycosylation included a methyl addition to the lactone carbonyl group, which was optimized to give the desired key intermediate in a yield of 70 %. The further conversion to lactiflorin was achieved in four steps and with an overall yield of 49 %.
Lipid‐transfer proteins
Authors: Ng Tzi Bun , Cheung Randy Chi Fai , Wong Jack Ho , Ye Xiujuan
Published: May 2012

Lipid‐transfer proteins (LTPs) are basic proteins found in abundance in higher plants. LTPs play lots of roles in plants such as participation in cutin formation, embryogenesis, defense reactions against phytopathogens, symbiosis, and the adaptation of plants to various environmental conditions. In addition, LTPs from field mustard and Chinese daffodil exhibit antiproliferative activity against human cancer cells. LTPs from chili pepper and coffee manifest inhibitory activity against fungi pathogenic to humans such as Candida species. The intent of this article is to review LTPs in the plant kingdom. © 2012 Wiley Periodicals, Inc. Biopolymers (Pept Sci) 98: 268‐279, 2012.
Quantification of homocysteine‐related metabolites and the role of betaine–homocysteine S‐methyltransferase in HepG2 cells
Authors: Kořínek Marek , Šístek Václav , Mládková Jana , Mikeš Petr , Jiráček Jiří , Selicharová Irena
Published: May 2012

We optimized and validated a rapid and sensitive liquid chromatography–tandem mass spectrometry (LC‐MS/MS) method for the quantification of six metabolites of homocysteine metabolism: homocysteine, methionine, cysteine, S‐adenosylmethionine, S‐adenosylhomocysteine and betaine. The detection limits for these metabolites were in the nanomolar range, and the intra‐ and inter‐day precisions were lower than 20% of the relative standard deviations. The method was specifically designed for the determination of the intracellular concentrations of the metabolites in cultured cells. To study the role of betaine–homocysteine S‐methyltransferase (BHMT), HepG2 cells and HepG2 cells that were stably transfected with BHMT (BHMTHepG2) were treated with homocysteine or with a specific inhibitor of BHMT, and metabolite levels were subsequently measured. Severely compromised methyl group metabolism in the HepG2 cells, which is typical of cancer‐derived cells, prevented clear evaluation of the changes caused by the external manipulations of homocysteine metabolism. However, the ease of handling these cells and the almost unlimited source of experimental material supplied by cells in permanent culture allowed us to develop a reliable methodology. The precautions concerning intracellular metabolite determinations using LC‐MS/MS in cultured cells that are expressed in this work will have global validity for future metabolomics studies. Copyright © 2012 John Wiley & Sons, Ltd.
ChemInform Abstract: Structure and Hydrogenation Study of Nickel Substituted NdCo3NiB.
Authors: Soulie J‐Ph. , Penin N. , Yvon K.
Published: May 2012

The title compound is characterized by neutron diffraction and hydrogen cycling experiments.
ChemInform Abstract: H2Ti6O13, a New Protonated Titanate Prepared by Li+/H+ Ion Exchange: Synthesis, Crystal Structure and Electrochemical Li Insertion Properties.
Authors: Perez‐Flores J. C. , Baehtz C. , Hoelzel M. , Kuhn A. , Garcia‐Alvarado F.
Published: May 2012

The title compound is synthesized by Li+/H+ ion exchange of Li2Ti6O13 using benzoic acid (125 °C in air, 72 h).
ChemInform Abstract: Synthesis, Crystal Structures, and Hydrogen‐Storage Properties of Eu(AlH4)2 and Sr(AlH4)2 and of Their Decomposition Intermediates, EuAlH5 and SrAlH5.
Authors: Pommerin Andre , Wosylus Aron , Felderhoff Michael , Schueth Ferdi , Weidenthaler Claudia
Published: May 2012

Eu(AlH4)2 and Sr(AlH4)2 are prepared by ball milling of stoichiometric mixtures of NaAlH4 and europium or strontium chloride and characterized by powder XRD and 27Al NMR spectroscopy.
ChemInform Abstract: Rich Coordination of Nd3+ in Mg2Nd13(BO3)8 (SiO4)4(OH)3, Derived from High‐Pressure/High‐Temperature Conditions.
Authors: Wu Shijun , Kegler Philip , Wang Shuao , Holzheid Astrid , Depmeier Wulf , Malcherek Thomas , Alekseev Evgeny V. , Albrecht‐Schmitt Thomas E.
Published: May 2012

The title compound is prepared by solid state reaction of MgO, Nd2O3, H3BO3, and SiO2 in the ratio of Mg:Nd:B:Si = 2:13:8:4 (Pt capsule, 4.5 GPa, 1400 °C, 1 h).
ChemInform Abstract: Na2EuAs2S5, NaEuAsS4, and Na4Eu(AsS4)2: Controlling the Valency of Arsenic in Polysulfide Fluxes.
Authors: Bera Tarun K. , Kanatzidis Mercouri G.
Published: May 2012

Depending on the relative As content and the basicity of the polysulfide flux, either the AsV compounds (V) and (VI) or the AsIII compound (VII) are obtained.
ChemInform Abstract: Thorium(IV)—Selenate Clusters Containing an Octanuclear Th(IV) Hydroxide/Oxide Core.
Authors: Knope Karah E. , Vasiliu Monica , Dixon David A. , Soderholm L.
Published: May 2012

[Th8(μ3‐O)4 (μ2‐OH)8(H2O)15 (SeO4)8]·7.5H2O (I) and [Th8(O)4(OH)8(H2O)17 (SeO4)8]·nH2O (II) are obtained from an aqueous slurry of Th(NO3)4, NH4OH, and H2SeO4 (boiling on a hot plate for about 10 min).
ChemInform Abstract: Highly Tunable Arylated Cinchona Alkaloids as Bifunctional Catalysts.
Authors: Quigley Cormac , Rodriguez‐Docampo Zaida , Connon Stephen J.
Published: May 2012

A variety of novel chinchona alkaloid‐derived organocatalysts is synthesized with the aim of rationally designing a library of catalysts in which the relative proximity and orientation of the catalytically relevant components can be modified systematically.
ChemInform Abstract: Catalytic anti‐Selective Asymmetric Henry (Nitroaldol) Reaction Catalyzed by Cu(I)—Amine—Imine Complexes.
Authors: Ji Yao Qiong , Qi Gao , Judeh Zaher M. A.
Published: May 2012

The complex derived from bisisoquinoline BIQ and CuCl effectively catalyzes the title reaction of both aromatic and aliphatic aldehydes in the presence of moisture and air to give the resulting nitroalcohols with moderate antiselectivity.
ChemInform Abstract: Ring‐Opening Reaction of Aziridines Using Aqueous Polyacrylamide (PAM) as the Reaction Medium.
Authors: Wang Yan , Zhang Ming Jie , Zhu Jie , Li Zhong Bo
Published: May 2012

The aqueous solution of polyacrylamide serves as reagent, catalyst, and reaction medium.
ChemInform Abstract: Dimethyl Carbonate in the Regio‐ and Stereocontrolled Opening of Three‐Membered Heterocyclic Rings.
Authors: Righi Giuliana , Bovicelli Paolo , Barontini Maurizio , Tirotta Ilaria
Published: May 2012

Harmful or carcinogenic solvents such as CH2Cl2, Et2O, MeCN or acetone can be successfully replaced by the more eco‐friendly medium dimethylcarbonate in nucleophilic ring‐opening reactions of oxiranes and aziridines.
ChemInform Abstract: Solvent‐Free Copper‐Catalyzed N‐Arylation of Amino Alcohols and Diamines with Aryl Halides.
Authors: Yin Huiqing , Jin Ming , Chen Wei , Chen Chen , Zheng Likang , Wei Ping , Han Shiqing
Published: May 2012

A simple method for C—N cross‐coupling of aryl halides and primary amines is developed.
ChemInform Abstract: CDI‐Mediated Monoacylation of Symmetrical Diamines and Selective Acylation of Primary Amines of Unsymmetrical Diamines.
Authors: Verma Sanjeev K. , Ghorpade Ramarao , Pratap Ajay , Kaushik M. P.
Published: May 2012

A convenient two‐step one‐pot procedure is developed for the preparation of carbamates (IV) and amides (V), (IX), (XI), and (XIV).
ChemInform Abstract: Ni‐Catalyzed, Domino Synthesis of Tertiary Alcohols from Secondary Alcohols.
Authors: Berini Christophe , Navarro Oscar
Published: May 2012

The use of an in situ generated N‐heterocyclic carbene allows for the synthesis of a variety of tertiary alcohols (III) from secondary alcohols (I) through a domino oxidation—addition protocol.
ChemInform Abstract: Modular Furanoside Pseudodipeptides and Thioamides, Readily Available Ligand Libraries for Metal‐Catalyzed Transfer Hydrogenation Reactions: Scope and Limitations.
Authors: Coll Mercedes , Ahlford Katrin , Pamies Oscar , Adolfsson Hans , Dieguez Montserrat
Published: May 2012

Two libraries containing 72 D‐xylose or D‐glucose derived pseudodipetides and thioamides, respectively are prepared as ligands for catalytic asymmetric transfer hydrogenation.
ChemInform Abstract: Chiral 2‐Aminobenzimidazole Bifunctional Organocatalysts: Effect of Di‐CF3 and TFA on Catalytic Mechanisms.
Authors: Lee Myungmo , Zhang Lei , Park Yohan , Park Hyeung‐geun
Published: May 2012

BIM is synthesized and applied to Michael addition of diethyl malonate to nitroolefins.
ChemInform Abstract: Manganese Oxide‐Catalyzed Transformation of Primary Amines to Primary Amides Through the Sequence of Oxidative Dehydrogenation and Successive Hydration.
Authors: Wang Ye , Kobayashi Hiroaki , Yamaguchi Kazuya , Mizuno Noritaka
Published: May 2012

The dual catalytic functions of manganese oxide octahedral molecular sieves allow for the oxygenation of primary amines (I) to the corresponding amides (II).
ChemInform Abstract: Cyanuric Chloride Catalyzed Beckmann Rearrangement of Ketoximes in Biodegradable Ionic Liquids.
Authors: Maia Angelamaria , Albanese Domenico C. M. , Landini Dario
Published: May 2012

The Beckmann‐type rearrangement, that is known to require strongly acidic media, is carried out in the presence of imidazolium‐based ionic liquids containing ester moieties in the side chain.
ChemInform Abstract: Sulfo‐Click Reaction via in situ Generated Thioacids and Its Application in Kinetic Target‐Guided Synthesis.
Authors: Namelikonda Niranjan Kumar , Manetsch Roman
Published: May 2012

A one‐pot variant of the sulfo‐click reaction in presented, in which protected thioesters (I) and (IV) are rapidly deprotected and further subjected to the reaction with sulfonylazides (II) and (V) to afford N‐acyl sulfonamides (III) and (VI), respectively.
ChemInform Abstract: Asymmetric Triple Cascade Organocatalytic Reaction in Water: Construction of Polyfunctional Cyclohexene Building Blocks Having Multiple Stereocenters.
Authors: Jia Yaomei , Mao Zhifeng , Wang Rui
Published: May 2012

The multicomponent reaction of a linear aldehyde, a nitroalkene, and an α,β‐unsaturated aldehyde in water affords cyclohexene derivatives bearing four stereogenic centers.
ChemInform Abstract: Synthesis of 1,2‐Naphthalenediol Diacetates by Rhodium(II)‐Catalyzed Reaction of 1,2‐Diazonaphthoquinones with Acetic Anhydride.
Authors: Kitamura Mitsuru , Kisanuki Masato , Okauchi Tatsuo
Published: May 2012

Conversion of quinone (VI) leads to the desired product (VII) in low yield and imidoyl acetate (VIII) is isolated as the major product.
ChemInform Abstract: Asymmetric Synthesis of Wieland—Miescher and Hajos—Parrish Ketones Catalyzed by an Amino Acid Derived Chiral Primary Amine.
Authors: Zhou Pengxin , Zhang Long , Luo Sanzhong , Cheng Jin‐Pei
Published: May 2012

The amine efficiently promotes the enantioselective formation of the title ketones and related compounds.
ChemInform Abstract: HOTf Mediated Cascade Reactions of 1‐Arenoylcyclopropanecarboxylic Acids with Arenes.
Authors: Chen Gen‐Qiang , Tang Xiang‐Ying , Shi Min
Published: May 2012

Title cascade reaction provides access towards benzofluorene derivatives (III) and (V) as single diastereomers.
ChemInform Abstract: Cascade Assembly of the Benz[a]anthraquinone Ring System Common to the Angucycline Antibiotics.
Authors: Baranczak Aleksandra , Sulikowski Gary A.
Published: May 2012

A novel synthetic route to access compounds (X) and (XII), which represent the tetracyclic core structure of angucycline antiobiotics, is based on an optimized procedure for the desymmetrization of dibromide (III).
ChemInform Abstract: Regiodivergent Synthesis of Trisubstituted Furans Through Tf2O‐Catalyzed Friedel—Crafts Acylation: A Tool for Access to Tetrahydrofuran Lignan Analogues.
Authors: Comegna Daniela , DellaGreca Marina , Iesce M. Rosaria , Previtera Lucio , Zarrelli Armando , Zuppolini Simona
Published: May 2012

A tunable Tf2O‐mediated Friedel—Crafts acylation allows the synthesis of 3‐ and 4‐aroylated phenylfurans such as (III) or (IV) from the unique mono‐acid precursor (I).
ChemInform Abstract: Highly Regioselective Migration of the Sulfonyl Group: Easy Access to Functionalized Pyrroles.
Authors: Xin Xiaoyi , Wang Dongping , Li Xincheng , Wan Boshun
Published: May 2012

The first example of sulfonyl group migration in pyrrole synthesis to give selectively the compounds (II), (III), and (V) is presented.
ChemInform Abstract: Influence of Steric Parameters on the Synthesis of Tetramates from α‐Amino‐β‐alkoxy‐esters and Ph3PCCO.
Authors: Loke Inga , Park Natja , Kempf Karl , Jagusch Carsten , Schobert Rainer , Laschat Sabine
Published: May 2012

The domino addition—Wittig cyclization sequence produces enantiomerically pure tetramate structures.
ChemInform Abstract: One‐Pot Reductive Coupling of N‐Acylcarbamates with Activated Alkenes: Application to the Asymmetric Synthesis of Pyrrolo[1,2‐a]azepin‐5‐one Ring System and (‐)‐Xenovenine.
Authors: Liu Xue‐Kui , Zheng Xiao , Ruan Yuan‐Ping , Ma Jie , Huang Pei‐Qiang
Published: May 2012

A one‐pot method for the direct reductive coupling of N‐acylcarbamates with activated alkenes is based on the partial reduction with AlH(iBu)2, followed by acyliminium ion formation and SmI2‐mediated radical cross‐coupling with activated alkenes.
ChemInform Abstract: Asymmetric Synthesis of Highly Functionalized γ‐Lactams Through an Organocatalytic aza‐Michael—Michael Reaction Cascade Using Fumaric Acid Amide Esters as Multi‐Reactive Substrates.
Authors: Yokosaka Takuya , Hamajima Akinari , Nemoto Tetsuhiro , Hamada Yasumasa
Published: May 2012

The process employs primary and secondary amine organocatalysts allowing the synthesis of mono and bicyclic lactam frameworks.
ChemInform Abstract: Asymmetric Construction of Quaternary Stereocenters: Synthesis of Enantiopure Amino Acid‐Based Tricyclic α,β‐Enones Through an ipso‐Friedel—Crafts/Michael Addition Cascade.
Authors: Rodriguez‐Solla Humberto , Concellon Carmen , Tuya Paula , Garcia‐Granda Santiago , Rosario Diaz M.
Published: May 2012

Phenylalanine‐derived syn‐amino epoxide (V*) shows a different behavior than the related compounds (I) and (III) according to a previously published study.
ChemInform Abstract: Regioselective Conversion of Alkynes to 4‐Substituted and 3,4‐Disubstituted Isoxazoles Using Titanium‐Catalyzed Multicomponent Coupling Reactions.
Authors: Dissanayake Amila A. , Odom Aaron L.
Published: May 2012

A one‐pot method for the synthesis of the title compounds (III), (V), and (VII) is developed.
ChemInform Abstract: Practical Synthesis of β‐Oxo Benzo[d]thiazolyl Sulfones: Scope and Limitations.
Authors: Pospisil Jiri , Robiette Raphael , Sato Hitoshi , Debrus Kevin
Published: May 2012

A short and efficient approach to α‐acyl and α‐carboxylic acid derived sulfones such as (III) or (V) is reported.
ChemInform Abstract: Regioselective Synthesis of 5‐Trifluoromethyl‐1,2,3‐triazoles via CF3‐Directed Cyclization of 1‐Trifluoromethyl‐1,3‐dicarbonyl Compounds with Azides.
Authors: Rozin Yury A. , Leban Johann , Dehaen Wim , Nenajdenko Valentine G. , Muzalevskiy Vasiliy M. , Eltsov Oleg S. , Bakulev Vasiliy A.
Published: May 2012

A general and highly selective method for the synthesis of the title compounds (III) and (V), which are obtained as single isomer, is presented.
ChemInform Abstract: Synthesis and Antitumor Activity of a Novel Class of Flavanones: 1,4‐Diaryl‐1,4‐dihydrochromeno[4,3‐c]pyrazoles.
Authors: Chen Zhiwei , Wang Zhihua , Su Weike
Published: May 2012

A novel and efficient method for the synthesis of new diaryldihydrochromenopyrazoles from corresponding flavanones is developed.
ChemInform Abstract: Intramolecular 1,3‐Dipolar Nitrile Oxide Cycloaddition Using Baylis—Hillman Derivatives: Stereoselective Synthesis of Tricyclic Chromenoisoxazolines.
Authors: Bakthadoss Manickam , Srinivasan Jayakumar , Selvakumar Raman
Published: May 2012

The title method provides the required heterocyclic systems (III) and (VI) in a stereoselective manner.
ChemInform Abstract: One‐Pot Synthesis of 4‐Substituted 3,4‐Dihydro‐3‐methoxyisocoumarins via Carboxylation of α‐Substituted 2‐Lithio‐β‐methoxystyrenes with Carbon Dioxide.
Authors: Kobayashi Kazuhiro , Nagaoka Toshiyuki , Shirai Yuu , Miyatani Wataru , Yokoi Yuki , Konishi Hisatoshi
Published: May 2012

Carboxylation of α‐substituted 2‐lithio‐β‐methoxystyrenes followed by acid‐mediated lactonization opens a convenient route to the title compounds.
ChemInform Abstract: A New Synthesis of 5‐Arylbenzo[c]xanthones from Photoinduced Electrocyclization and Oxidation of (E)‐3‐Styrylflavones.
Authors: Rocha Djenisa H. A. , Pinto Diana C. G. A. , Silva Artur M. S. , Patonay Tamas , Cavaleiro Jose A. S.
Published: May 2012

The title compounds are of interest as structural motifs of natural products and as heterocyclic skeletons in drug development.
ChemInform Abstract: FeCl3·6H2O‐Catalyzed Intermolecular‐Cascade Cyclization of Acetoacetanilide: Aldehyde‐Tuned Synthesis to Valuable 2‐Pyridone Analogues.
Authors: Sengupta Tista , Gayen Krishnanka S. , Pandit Palash , Maiti Dilip K.
Published: May 2012

Aromatic, aliphatic, chiral sugar‐based and chromone aldehydes are regio‐ and stereoselectively cyclized with acetoacetanilides.
ChemInform Abstract: Synthesis and Anticonvulsant Activity of 1‐(8‐(Benzyloxy)quinolin‐2‐yl)‐6‐substituted‐4,6‐diazaspiro [2,4]heptane‐5,7‐diones.
Authors: He Xianran , Zhong Min , Zhang Tao , Yang Jin , Wu Zhongyuan , Xiao Yuling , Guo Hao , Qiu Guofu , Hu Xianming
Published: May 2012

A variety of new diazaspiroheptanediones (XII) (16 examples) are synthesized and evaluated for their anticonvulsant activity.
ChemInform Abstract: Chiral Aziridine‐2‐carboxylates: Versatile Precursors for Functionalized Tetrahydroisoquinoline (THIQ) Containing Heterocycles.
Authors: Lee Kyu Myung , Kim Jong Chan , Kang Philjun , Lee Won Koo , Eum Heesung , Ha Hyun‐Joon
Published: May 2012

An effective route for the synthesis of enantiomerically pure title compounds (IX) is developed from aziridine (I) using simple organic transformations.
ChemInform Abstract: A New Entry to the Phenanthridine Ring System.
Authors: Mondal Poulomi , Thander Latibuddin , Chattopadhyay Shital K.
Published: May 2012

The synthesis of target compounds (VIII) having diversity in rings A and C involves Ru‐catalyzed ring‐closing metathesis of the N‐propargyl anilines (IV) followed by Diels—Alder reaction with acetylene dicarboxylates.
ChemInform Abstract: Three‐Component One‐Pot Synthesis of Pyrazolo[3,4‐b]quinolin‐5(6H)‐one Derivatives in Aqueous Media.
Authors: Wang Hui‐Yan , Shi Da‐Qing
Published: May 2012

Compared with hitherto known methods, this new protocol has the advantages of convenient operation, higher yields, lower costs and an environmentally benign procedure.
ChemInform Abstract: Discovery of 7‐Arylsulfonyl‐1,2,3,4,4a,9a‐hexahydro‐benzo[4,5]furo[2,3‐c]pyridines: Identification of a Potent and Selective 5‐HT6 Receptor Antagonist (I) Showing Activity in Rat Social Recognition Test.
Authors: Tripathy Rabindranath , et al. et al.
Published: May 2012

The key step in the synthesis of (I) is the CuI‐mediated coupling reaction between methoxy‐isopropyloxybenzenethiol and 7‐iodo‐hexahydro‐benzofuropyridine followed by S‐oxidation with MCPBA.
ChemInform Abstract: Microwave‐Assisted Multicomponent Reaction of Aryl Amidines: Regiospecific Synthesis of New Polysubstituted Thiopyrano‐, and Pyrano[4,3‐d]pyrimidines.
Authors: Jiang Bo , Xue Li‐Yuan , Wang Xing‐Han , Tu Man‐Su , Liu Yin‐Ping , Tu Shu‐Jiang
Published: May 2012

A novel pseudo four‐component reaction of 4‐pyranones or thiones with aromatic aldehydes and arylamidines is established to provide the anellated pyrimidines regioselectively.
ChemInform Abstract: A Transition Metal‐Free Tandem Process to Pyrrolopyrazino[2,3‐d]pyridazine‐diones.
Authors: Huang Aiping , Qiao Zhi , Zhang Xinhai , Yu Wei , Zheng Qingqing , Ma Ying , Ma Chen
Published: May 2012

An effective and simple method for the synthesis of the title compounds (III) and (IV) is presented.
ChemInform Abstract: A New Approach for the Synthesis of Some Pyrazolo[5,1‐c]triazines and Pyrazolo[1,5‐a]pyrimidines Containing Naphthofuran Moiety.
Authors: Abdelhamid Abdou O. , Shokry Shokry A. , Tawfiek Sayed M.
Published: May 2012

Title pyrazolotriazines (III) and pyrazolopyrimidines (V) are obtained by reaction of the naphthofuranyl‐carbonyl‐bearing enolate (I) with either pyrazolyldiazonium salts (II) or the corresponding amines (IV).
ChemInform Abstract: Benzoxaborole Antimalarial Agents. Part 2. Discovery of Fluoro‐Substituted 7‐(2‐Carboxyethyl)‐1,3‐dihydro‐1‐hydroxy‐2,1‐benzoxaboroles.
Authors: Zhang Yong‐Kang , et al. et al.
Published: May 2012

Structure‐activity relationship was investigated by changing the substitution pattern at the aromatic ring of the benzoxaboroles.
ChemInform Abstract: Cytotoxic ent‐Kaurane Diterpenoids from Isodon henryi
Authors: Pu Jian‐Xin , et al. et al.
Published: May 2012

isolation, structure elucidation, and cytotoxic activity of new ent‐kaurane diterpenoids, isodonhenrins A—E (I)—(V), and thirteen known analogues
ChemInform Abstract: Enantiospecific Synthesis of Pacifigorgianes
Authors: Srikrishna A. , Dethe Dattatraya H.
Published: May 2012

using entropy assisted ring‐closing metathesis reactions as the key step
ChemInform Abstract: Total Synthesis and Stereochemical Revision of Burkholdac A.
Authors: Liu Junyang , Ma Xiao , Liu Yuqing , Wang Zhuo , Kwong Shuqin , Ren Qi , Tang Shoubin , Meng Yi , Xu Zhengshuang , Ye Tao
Published: May 2012

Total synthesis of the proposed structure (II) results in differences concerning the NMR spectra of the natural product.
ChemInform Abstract: Chemical and Physical Characterization of Produced Waters from Conventional and Unconventional Fossil Fuel Resources
Authors: Alley Bethany , Beebe Alex , Rodgers John Jr. , Castle James W.
Published: May 2012

Review: 59 refs.
ChemInform Abstract: Hydrogen Bonding Donor‐Acceptor Carbon Nanostructures
Authors: Herranz Ma. Angeles , Giacalone Francesco , Sanchez Luis , Martin Nazario
Published: May 2012

Review: 195 refs.
ChemInform Abstract: Solid State Ionic Tools for Catalysis and Materials Research: In Honor of Robert A. Huggins
Authors: Guer Turgut M.
Published: May 2012

Review: 52 refs.
ChemInform Abstract: Crystal Chemistry and Properties of Mullite‐Type Bi2M4O9: An Overview
Authors: Schneider Hartmut , Fischer Reinhard X. , Gesing Thorsten M. , Schreuer Juergen , Muehlberg Manfred
Published: May 2012

Review: [M: Al, Ga, Fe]
ChemInform Abstract: Imidazole Derivatives: A Comprehensive Survey of Their Recognition Properties
Authors: Molina Pedro , Tarraga Alberto , Oton Francisco
Published: May 2012

Review: 98 refs.
ChemInform Abstract: Recent Advances in Antitubercular Natural Products
Authors: Garcia Abraham , Bocanegra‐Garcia Virgilio , Palma‐Nicolas Jose Prisco , Rivera Gildardo
Published: May 2012

Review: 117 refs.
ChemInform Abstract: Transition Metal Based Catalysts in the Aerobic Oxidation of Alcohols
Authors: Parmeggiani Camilla , Cardona Francesca
Published: May 2012

Review: 158 refs.
ChemInform Abstract: Aurones: Interesting Natural and Synthetic Compounds with Emerging Biological Potential
Authors: Zwergel Clemens , Gaascht Francois , Valente Sergio , Diederich Marc , Bagrel Denyse , Kirsch Gilbert
Published: May 2012

Review: 37 refs.
ChemInform Abstract: Heterogeneous Azide—Alkyne Click Chemistry: Towards Metal‐Free End Products
Authors: Dervaux Bart , Du Prez Filip E.
Published: May 2012

Review: 84 refs.
ChemInform Abstract: Advances in N‐ and O‐Glycopeptide Synthesis ‐ a Tool to Study Glycosylation and Develop New Therapeutics
Authors: Westerlind Ulrika , Kunz Horst
Published: May 2012

Review: 175 refs.
ChemInform Abstract: Synthesis of Pyridine and Dihydropyridine Derivatives by Regio‐ and Stereoselective Addition to N‐Activated Pyridines
Authors: Bull James A. , Mousseau James J. , Pelletier Guillaume , Charette Andre B.
Published: May 2012

Review: 548 refs.
ChemInform Abstract: Formation of Charge and Spin Ordering in Strongly Correlated Electron Systems
Authors: Cencarikova H. , Farkasovsky P.
Published: May 2012

Review: 132 refs.
ChemInform Abstract: Diketopyrrolopyrrole (DPP)‐Based Materials for Organic Photovoltaics
Authors: Qu Sanyin , Tian He
Published: May 2012

Review: 108 refs.
ChemInform Abstract: Theoretical Modeling of 13C NMR Chemical Shifts — How to Use the Calculation Results
Authors: Gryff‐Keller Adam
Published: May 2012

Review: 74 refs.
ChemInform Abstract: X‐Ray Probes for in situ Studies of Interfaces
Authors: Fong D. D. , Lucas C. A. , Richard M.‐I. , Toney M. F.
Published: May 2012

Review: 96 refs.
Do Non‐profit Organizations Manage Earnings toward Zero Profit and Does Governmental Financing Play a Role?
Authors: Verbruggen Sandra , Christiaens Johan
Published: May 2012

Prior research has documented earnings management in for‐profit settings. Non‐profit organizations are thought to pay less attention to the bottom line and earnings management research has therefore focused on the manipulation of expenses in order to improve efficiency ratios or taxable income, not reported earnings per se. Considering an institutional setting characterized by the absence of such ratios and the presence of important subsidies, management of the actual bottom line is analyzed in light of these subsidies. The results suggest that organizations drive their results toward zero profit, which is intensified by increased governmental funding when unmanaged results are positive. The relation between downward earnings management and the presence of subsidies is particularly evident for organizations whose accumulated reserves are high. Copyright © 2012 ASAC. Published by John Wiley & Sons, Ltd.
Improved measurement of labile proton concentration‐weighted chemical exchange rate (kws) with experimental factor‐compensated and T1‐normalized quantitative chemical exchange saturation transfer (CEST) MRI
Authors: Wu Renhua , Liu Charng‐Ming , Liu Philip K , Sun Phillip Zhe
Published: May 2012

Chemical exchange saturation transfer (CEST) MRI enables measurement of dilute CEST agents and microenvironment properties such as pH and temperature, holding great promise for in vivo applications. However, because of confounding concomitant radio frequency (RF) irradiation and relaxation effects, the CEST‐weighted MRI contrast may not fully characterize the underlying CEST phenomenon. We postulated that the accuracy of quantitative CEST MRI could be improved if the experimental factors (labeling efficiency and RF spillover effect) were estimated and taken into account. Specifically, the experimental factor was evaluated as a function of exchange rate and CEST agent concentration ratio, which remained relatively constant for intermediate RF irradiation power levels. Hence, the experimental factors can be calculated based on the reasonably estimated exchange rate and labile proton concentration ratio, which significantly improved quantification. The simulation was confirmed with creatine phantoms of serially varied concentration titrated to the same pH, whose reverse exchange rate (kws) was found to be linearly correlated with the concentration. In summary, the proposed solution provides simplified yet reasonably accurate quantification of the underlying CEST system, which may help guide the ongoing development of quantitative CEST MRI. Copyright © 2012 John Wiley & Sons, Ltd.
Practical demonstration of the CIEDE2000 corrections to CIELAB using a small set of sample pairs
Authors: Melgosa Manuel , Alman David H. , Grosman Martina , Gómez‐Robledo Luis , Trémeau Alain , Cui Guihua , García Pedro A. , Vázquez Daniel , Li Changjun , Luo Ming Ronnier
Published: May 2012

A set of 10 color pairs was proposed and produced in 2002 to show the advantages of the CIEDE2000 color‐difference formula with respect to CIELAB. These 10 color pairs illustrated each of the five corrections to CIELAB proposed by CIEDE2000. The 10 color pairs were visually assessed, under reference conditions close to those proposed by CIEDE2000, by two groups of 31 and 21 inexperienced observers, using two different gray scales. Average visual results in these experiments fitted CIEDE2000 predictions much better than CIELAB, as shown by a decrease of Standardized Residual Sum of Squares values of about 20 units. Current visual results showed only the improvement of CIEDE2000 upon CIELAB in predictions of perceived color differences, but they are not recommended for testing new advanced color‐difference formulas. © 2012 Wiley Periodicals, Inc. Col Res Appl, 38, 429–436, 2013.
Applying reinforcement learning towards automating resource allocation and application scalability in the cloud
Authors: Barrett Enda , Howley Enda , Duggan Jim
Published: May 2012

Public Infrastructure as a Service (IaaS) clouds such as Amazon, GoGrid and Rackspace deliver computational resources by means of virtualisation technologies. These technologies allow multiple independent virtual machines to reside in apparent isolation on the same physical host. Dynamically scaling applications running on IaaS clouds can lead to varied and unpredictable results because of the performance interference effects associated with co‐located virtual machines. Determining appropriate scaling policies in a dynamic non‐stationary environment is non‐trivial. One principle advantage exhibited by IaaS clouds over their traditional hosting counterparts is the ability to scale resources on‐demand. However, a problem arises concerning resource allocation as to which resources should be added and removed when the underlying performance of the resource is in a constant state of flux. Decision theoretic frameworks such as Markov Decision Processes are particularly suited to decision making under uncertainty. By applying a temporal difference, reinforcement learning algorithm known as Q‐learning, optimal scaling policies can be determined. Additionally, reinforcement learning techniques typically suffer from curse of dimensionality problems, where the state space grows exponentially with each additional state variable. To address this challenge, we also present a novel parallel Q‐learning approach aimed at reducing the time taken to determine optimal policies whilst learning online. Copyright © 2012 John Wiley & Sons, Ltd.
Differential effects of ret and TRKB on axonal branching and survival of parasympathetic neurons
Authors: Simpson Julie , Keefe Julie , Nishi Rae
Published: May 2012

Interactions between neurons and their targets of innervation influence many aspects of neural development. To examine how synaptic activity interacts with neurotrophic signaling, we determined the effects of blocking neuromuscular transmission on survival and axonal outgrowth of ciliary neurons from the embryonic chicken ciliary ganglion. Ciliary neurons undergo a period of cell loss due to programmed cell death between embryonic Days (E) 8 and 14 and they innervate the striated muscle of the iris. The nicotinic antagonist d‐tubocurarine (dTC) induces an increase in branching measured by counting neurofilament‐positive voxels (NF‐VU) in the iris between E14‐17 while reducing ciliary neuron survival. Blocking ganglionic transmission with dihyro‐β‐erythroidin and α‐methyllycacontine does not mimic dTC. At E8, many trophic factors stimulate neurite outgrowth and branching of neurons placed in cell culture; however, at E13, only GDNF stimulates branching selectively in cultured ciliary neurons. The GDNF‐induced branching at E13 could be inhibited by BDNF. Blocking ret signaling in vivo with a dominant negative (dn)ret decreases survival of ciliary and choroid neurons at E14 and prevents dTC induced increases in NF‐VU in the iris at E17. Blocking TRKB signaling with dn TRKB increases NF‐VU in the iris at E17 and decreases neuronal survival at E17, but not at E14. Thus, RET promotes survival during programmed cell death in the ciliary ganglion and contributes to promoting branching when synaptic transmission is blocked while TRKB inhibits branching and promotes maintenance of neuronal survival. These studies highlight the multifunctional nature of trophic molecule function during neuronal development. © 2012 Wiley Periodicals, Inc. Develop Neurobiol, 2013