bluuebunny/crossref_metadata_2025 huggingface dataset:
Correlation of solubility of single gases/hydrocarbons in polyethylene using PC‐SAFT
Authors: Maity Sunil K.
Published: March 2011

The knowledge of solubility of gases and hydrocarbons in polymer has enormous importance in the design and development of reactor, polymer foaming, and membrane separation processes. In this work, the solubility of gases and hydrocarbons in polyethylene was correlated using a thermodynamic model based on perturbed‐chain statistical associating fluid theory (PC‐SAFT). The experimental solubility data of various gases such as ethylene, carbon dioxide, nitrogen, methane, and hydrocarbons of up to chain length of seven in both molten and semicrystalline polyethylene has been reviewed and the suitability of the developed model based on PC‐SAFT was then tested using the available solubility data in literatures for various gases and hydrocarbons. Furthermore, the optimum values of adjustable solvents‐solute binary interaction parameters (Kij) of PC‐SAFT at different temperatures have been estimated by regression of the PC‐SAFT model using experimental solubility isotherms. A suitable correlation of Kij with temperature was then developed using the estimated Kij at different temperatures. The solubility calculated from the developed model using the estimated Kij was then compared to the experimental results and a reasonably good correlation was observed. © 2011 Curtin University of Technology and John Wiley & Sons, Ltd.
Rice hull biocomposites. I. Preparation of a linseed‐oil‐based resin reinforced with rice hulls
Authors: Quirino Rafael L. , Larock Richard C.
Published: March 2011

Biocomposites consisting of a conjugated linseed‐oil (CLO)‐based thermoset reinforced with rice hulls were prepared by free‐radical polymerization initiated by t‐butyl peroxide. The resin composition was kept constant at 50 wt % CLO, 35 wt % n‐butyl methacrylate, and 15 wt % divinylbenzene. Tensile tests, dynamic mechanical analysis, thermogravimetric analysis, Soxhlet extraction, and differential scanning calorimetry were used to establish the ideal cure sequence. The pressure during cure, filler load, and the drying and grinding of the filler were varied, and their effects on the final properties of the composites were assessed. Optimal conditions were established for the preparation of rice hull biocomposites. Scanning electron microscopy showed a weak filler–resin interaction and X‐ray mapping suggested the presence of silica in the rice hulls; this have accounted for the high thermal and mechanical properties obtained for these composites. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Superparamagnetic latex synthesized by a new route of emulsifier‐free emulsion polymerization
Authors: Beyaz Seda , Tanrisever Taner , Kockar Hakan , Butun Vural
Published: March 2011

The aim of this study was to design polymeric nanospheres containing magnetic nanoparticle which could display superparamagnetic behavior and thus find application in allied fields. First magnetite nanoparticles were synthesized with coprecipitation method and then their stable acidic dispersion was prepared without surfactant and dropped into the polymerization system during a certain time interval after the polymerization started. The effects of time at which the magnetic sol was added into polymerization system on latex size and stability, average molecular weight of polymer were examined in the case of two different monomer concentrations. Extensive characterization by transmission electron microscopy, dynamic light scattering, thermal gravimetric analysis and magnetic measurements shows that when the magnetic sol was dropped during earlier time of polymerization at stage 1, the latex size, average molecular weight of polymer, thermal stability of polymeric composite, and saturation magnetization reduced, whereas polydispersity of size and molecular weight increased because of the reaction between persulfate and naked surface of magnetite at the aqueous phase. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011
Histological and Stereological Changes in Growing and Regressing Chicken Ovaries During Development
Authors: González‐Morán María Genoveva
Published: March 2011

The aim of this study was to evaluate the sequence of the histological and stereological changes that occur in diverse components of left growing and right regressing ovaries of Gallus domesticus as well as the variations in the number and size of the different cell subpopulations from 8‐day‐old chicken embryo to 4‐week‐old chickens. Results indicate a bilateral asymmetry in favor of the left ovary at all ages studied. The left ovary shows cortex and medulla, but the right ovary has no cortex, only a medulla. Stereological results show in the left ovary an increase in total volume of all components of the ovarian medulla with advancing development. The right ovary follows a similar pattern until the age of 1‐day‐old chicken, to regress afterward, thereby, reducing the total volume of blood vessels, lacunar channels, and interstitium, but increasing the total volume of interstitial cells as development progresses; consequently, the total volume of interstitial cells is the dominant component in the right ovary of 4‐week‐old chickens. Results also reveal that the increase in total volume of interstitial cells in the left ovary at all ages and in the right ovary from 8‐day‐old chicken embryo to 1‐day‐old chicken is due to hyperplasia and cell hypertrophy of interstitial cells; hence, in the right ovary, cell hypertrophy is the main cause for the increase in the total volume of interstitial cells from 1‐week‐old to 4‐week‐old chickens. Anat Rec, 2011. © 2011 Wiley‐Liss, Inc.
Protein Release from Biodegradable PolyHPMA–Lysozyme Conjugates Resulting in Bioactivity Enhancement
Authors: Tao Lei , Chen Gaojian , Zhao Lixiang , Xu Jiangtao , Huang Edwin , Liu Aiping , Marquis Christopher P. , Davis Thomas P.
Published: March 2011

A novel biodegradable thiazolidine‐2‐thione functional chain transfer agent was synthesized and employed as a reversible additional fragmentation chain transfer agent to prepare well‐defined semitelechelic poly‐N‐(2‐hydroxypropyl) methacrylamides (polyHPMAs) with predetermined molecular weights and narrow polydispersities. The protein reactive group, thiazolidine‐2‐thione, was located at the polymer chain ends fixed by biodegradable disulfide bonds. The functional polyHPMA chains were subsequently conjugated to protein (lysozyme) by exploiting reactions between the thiazolidine‐2‐thione functionality and amine residues on the protein surface to form covalent amide linkages. The in vitro bioactivities of the lysozyme–polyHPMA conjugates were assessed by using Micrococcus lysodeikticus cells as substrates. The lysozyme bioactivity was significantly reduced following the conjugation procedure. However, cleavage of the polymer chains from the bioconjugates (under reducing conditions) yielded free protein and a remarkable recovery of bioactivity. In vivo tests were performed by subcutaneous injection into mice and clearly demonstrated decreased proteolytic degradation for the protein–polymer conjugate when compared with native protein, indicating effective protein protection through a conjugation strategy. This bioreversible approach to conjugation allows for a balance to be made between protein protection and effective bioactivity maintenance.
Aminoluciferins as Functional Bioluminogenic Substrates of Firefly Luciferase
Authors: Takakura Hideo , Kojima Ryosuke , Urano Yasuteru , Terai Takuya , Hanaoka Kenjiro , Nagano Tetsuo
Published: March 2011

Firefly luciferase is widely used as a reporter gene in assays to study gene expression, gene delivery, and so on because of its extremely high signal‐to‐noise ratio. The availability of a range of bioluminogenic substrates would greatly extend the applicability of the luciferin–luciferase system. Herein, we describe a design concept for functional bioluminogenic substrates based on the aminoluciferin (AL) scaffold, together with a convenient, high‐yield method for synthesizing N‐alkylated ALs. We confirmed the usefulness of ALs as bioluminogenic substrates by synthesizing three probes. The first was a conjugate of AL with glutamate, Glu–AL. When Glu–AL, the first membrane‐impermeable bioluminogenic substrate of luciferases, was applied to cells transfected with luciferase, luminescence was not observed; that is, by using Glu–AL, we can distinguish between intracellular and extracellular events. The second was Cy5–AL, which consisted of Cy5, a near‐infrared (NIR) cyanine fluorescent dye, and AL, and emitted NIR light. When Cy5–AL reacted with luciferase, luminescence derived from Cy5 was observed as a result of bioluminescence resonance energy transfer (BRET) from AL to Cy5. The NIR emission wavelength would allow a signal to be observed from deeper tissues in bioluminescence in vivo imaging. The third was biotin–DEVD–AL (DEVD=the amino acid sequence Asp‐Glu‐Val‐Asp), which employed a caspase‐3 substrate peptide as a switch to control the accessibility of the substrate to luciferase, and could detect the activity of caspase‐3 in a time‐dependent manner. This generalized design strategy should be applicable to other proteases. Our results indicate that the AL scaffold is appropriate for a range of functional luminophores and represents a useful alternative substrate to luciferin.
Construction of Saccharomyces cerevisiae strains with enhanced ethanol tolerance by mutagenesis of the TATA‐binding protein gene and identification of novel genes associated with ethanol tolerance
Authors: Yang Jungwoo , Bae Ju Yun , Lee Young Mi , Kwon Hyeji , Moon Hye‐Yun , Kang Hyun Ah , Yee Su‐bog , Kim Wankee , Choi Wonja
Published: March 2011

Since elevated ethanol is a major stress during ethanol fermentation, yeast strains tolerant to ethanol are highly desirable for the industrial scale ethanol production. A technology called global transcriptional machinery engineering (gTME), which exploits a mutant library of SPT15 encoding the TATA‐binding protein of Saccharomyces cerevisiae (Alper et al., 2006; Science 314: 1565–1568), seems to a powerful tool for creating ethanol‐tolerant strains. However, the ability of created strains to tolerate high ethanol on rich media remains unproven. In this study, a similar strategy was used to obtain five strains with enhanced ethanol tolerance (ETS1–5) of S. cerevisiae. Comparing global transcriptional profiles of two selected strains ETS2 and ETS3 with that of the control identified 42 genes that were commonly regulated with twofold change. Out of 34 deletion mutants available from a gene knockout library, 18 were ethanol sensitive, suggesting that these genes were closely associated with ethanol tolerance. Eight of them were novel with most being functionally unknown. To establish a basis for future industrial applications, strains iETS2 and iETS3 were created by integrating the SPT15 mutant alleles of ETS2 and ETS3 into the chromosomes, which also exhibited enhanced ethanol tolerance and survival upon ethanol shock on a rich medium. Fermentation with 20% glucose for 24 h in a bioreactor revealed that iETS2 and iETS3 grew better and produced approximately 25% more ethanol than a control strain. The ethanol yield and productivity were also substantially enhanced: 0.31 g/g and 2.6 g/L/h, respectively, for control and 0.39 g/g and 3.2 g/L/h, respectively, for iETS2 and iETS3. Thus, our study demonstrates the utility of gTME in generating strains with enhanced ethanol tolerance that resulted in increase of ethanol production. Strains with enhanced tolerance to other stresses such as heat, fermentation inhibitors, osmotic pressure, and so on, may be further created by using gTME. Biotechnol. Bioeng. 2011; 108:1776–1787. © 2011 Wiley Periodicals, Inc.
Systematic review and meta-analysis of growth rates of small abdominal aortic aneurysms
Authors: Powell J T , Sweeting M J , Brown L C , Gotensparre S M , Fowkes F G , Thompson S G
Published: March 2011

Background

Small abdominal aortic aneurysms are usually asymptomatic and managed safely in ultrasound surveillance programmes until they grow to a diameter threshold where intervention is considered. The aim of this study was to synthesize systematically the published data on growth rates for small aneurysms to investigate the evidence basis for surveillance intervals.

Methods

This was a systematic review of the literature published before January 2010, which identified 61 potentially eligible reports. Detailed review yielded 15 studies providing growth rates for aneurysms 3·0–5·5 cm in diameter (14 in millimetres per year, 1 as percentage change per year). These studies included 7630 people (predominantly men) enrolled during 1976–2005.

Results

The pooled mean growth rate was 2·32 (95 per cent confidence interval 1·95 to 2·70) mm/year but there was very high heterogeneity between studies; the growth rate ranged from − 0·33 to + 3·95 mm/year. Six studies reported growth rates by 5-mm diameter bands, which showed the trend for growth rate to increase with aneurysm diameter. Simple methods to determine growth rate were associated with higher estimates. Meta-regression analysis showed that a 10-mm increase in aneurysm diameter was associated with a mean(s.e.m.) 1·62(0·20) mm/year increase in growth rate. Neither mean age nor percentage of women in each study had a significant effect. On average, a 3·5-cm aneurysm would take 6·2 years to reach 5·5 cm, whereas a 4·5-cm aneurysm would take only 2·3 years.

Conclusion

There was considerable variation in the reported growth rates of small aneurysms beyond that explained by aneurysm diameter. Fuller evidence on which to base surveillance intervals for patients in screening programmes requires a meta-analysis based on individual patient data.
Comparative study of three audio processors as environments for laboratory activities on wave physics and acoustics
Authors: Pejuan Arcadi , Bohigas Xavier , Jaén Xavier , Periago Cristina
Published: March 2011

Audio processors allow to implement laboratory activities specially on acoustics. We have evaluated three audio processors (Audacity, WaveLab, and Adobe Audition). Although an overall grade was also calculated as a guideline (not a statement of “the best”), the decision about the most suitable one depends on each particular laboratory activity. © 2011 Wiley Periodicals, Inc. Comput Appl Eng Educ 21:E89–E99, 2013
Percutaneous treatment of late‐aortic pseudoaneurysm resulting from surgical repair of aortic coarctation
Authors: Aslam Mohammad Shakil , Haddadian Babak , Bajwa Tanvir
Published: March 2011

We describe the case of a 38‐year‐old woman who presented with symptoms of chest pain and shortness of breath that had worsened over the previous 6 months and was found to have a large pseudoaneurysm (PSA) of the thoracic aorta. She underwent surgical repair of aortic coarctation at the age of 16 and a revision of her bypass graft at age 28 when she presented with hemoptysis due to aortic PSA and aortobronchial fistula. Our cardiothoracic surgical team deemed a third surgery very high risk; therefore, she was referred to us for percutaneous repair of aortic PSA. We describe the successful treatment of the PSA using a technique of microcoil embolization and Amplatzer® vascular plug (AGA Medical Corp., Plymouth, MN).© 2011 Wiley‐Liss, Inc.
Rates of Water Exchange for Two Cobalt(II) Heteropolyoxotungstate Compounds in Aqueous Solution
Authors: Ohlin C. André , Harley Stephen J. , McAlpin J. Gregory , Hocking Rosalie K. , Mercado Brandon Q. , Johnson Rene L. , Villa Eric M. , Fidler Mary Kate , Olmstead Marilyn M. , Spiccia Leone , Britt R. David , Casey William H.
Published: March 2011

Polyoxometalate ions are used as ligands in water‐oxidation processes related to solar energy production. An important step in these reactions is the association and dissociation of water from the catalytic sites, the rates of which are unknown. Here we report the exchange rates of water ligated to CoII atoms in two polyoxotungstate sandwich molecules using the 17O‐NMR‐based Swift–Connick method. The compounds were the [Co4(H2O)2(B‐α‐PW9O34)2]10− and the larger αββα‐[Co4(H2O)2(P2W15O56)2]16− ions, each with two water molecules bound trans to one another in a CoII sandwich between the tungstate ligands. The clusters, in both solid and solution state, were characterized by a range of methods, including NMR, EPR, FT‐IR, UV‐Vis, and EXAFS spectroscopy, ESI‐MS, single‐crystal X‐ray crystallography, and potentiometry. For [Co4(H2O)2(B‐α‐PW9O34)2]10− at pH 5.4, we estimate: k298=1.5(5)±0.3×106 s−1, ΔH≠=39.8±0.4 kJ mol−1, ΔS≠=+7.1±1.2 J mol−1 K−1 and ΔV≠=5.6 ±1.6 cm3 mol−1. For the Wells–Dawson sandwich cluster (αββα‐[Co4(H2O)2(P2W15O56)2]16−) at pH 5.54, we find: k298=1.6(2)±0.3×106 s−1, ΔH≠=27.6±0.4 kJ mol−1 ΔS≠=−33±1.3 J mol−1 K−1 and ΔV≠=2.2±1.4 cm3mol−1 at pH 5.2. The molecules are clearly stable and monospecific in slightly acidic solutions, but dissociate in strongly acidic solutions. This dissociation is detectable by EPR spectroscopy as S=3/2 CoII species (such as the [Co(H2O)6]2+ monomer ion) and by the significant reduction of the Co–Co vector in the XAS spectra.
ChemInform Abstract: Enantioselective Synthesis of Optically Pure β‐Amino Ketones and γ‐Aryl Amines by Rh‐Catalyzed Asymmetric Hydrogenation.
Authors: Geng Huiling , Huang Kexuan , Sun Tian , Li Wei , Zhang Xiaowei , Zhou Le , Wu Wenjun , Zhang Xumu
Published: March 2011

It provides an efficient and highly enantioselective approach to a number of β‐amino ketones and γ‐aryl amines.
ChemInform Abstract: Direct Access to Cumbersome Aminated Quaternary Centers by Hyperbaric Aza‐Michael Additions.
Authors: Rulev Alexander Yu. , Azad Saleha , Kotsuki Hiyoshizo , Maddaluno Jacques
Published: March 2011

The aza‐Michael addition of secondary amines to α,β‐ or β,β‐disubstituted α,β‐unsaturated esters is efficiently achieved under high pressure (10—16 kbar) in protic solvents without any catalyst.
ChemInform Abstract: Asymmetric Organocatalytic Formal Aza‐Michael Addition of Ammonia to Nitroalkenes.
Authors: Lykke Lennart , Monge David , Nielsen Martin , Joergensen Karl Anker
Published: March 2011

Several protected β‐amino nitro compounds (III) are prepared in high yields and enantioselectivities.
ChemInform Abstract: One‐Pot Hydroxy Group Activation/Carbon—Carbon Bond Forming Sequence Using a Broensted Base/Broensted Acid System.
Authors: Devineau Alice , Pousse Guillaume , Taillier Catherine , Blanchet Jerome , Rouden Jacques , Dalla Vincent
Published: March 2011

Alkylation of hydroxylactams (I) is smoothly achieved by activation of the hydroxy group by Broensted base‐catalyzed trichloroacetimidation followed by Broensted acid‐catalyzed nucleophilic substitution of the trichloroacetimidate group.
ChemInform Abstract: Palladium‐Catalyzed Cross‐Coupling of Polyfluoroarenes with Simple Arenes.
Authors: Li Hu , Sun Chang‐Liang , Li Bi‐Jie , Shi Zhang‐Jie
Published: March 2011

Optimized conditions allow the preparation of various biphenyl products.
ChemInform Abstract: Enantioselective α‐ and γ‐Alkylation of α,β‐Unsaturated Aldehydes Using Dienamine Activation.
Authors: Stiller Julian , Marques‐Lopez Eugenia , Herrera Raquel P. , Froehlich Roland , Strohmann Carsten , Christmann Mathias
Published: March 2011

α‐Substitution is a favored path when branched aldehydes are used as substrates [cf.
ChemInform Abstract: o‐Iodoxybenzoic Acid Mediated Oxidative Desulfurization of 1,3‐Disubstituted Thioureas to Carbodiimides.
Authors: Chaudhari Pramod S. , Dangate Prasad S. , Akamanchi Krishnacharya G.
Published: March 2011

The advantages of the methodology are mild reaction conditions, ease of isolation, and suitability for a wide range of substrates.
ChemInform Abstract: Practical Synthesis of FEt‐Penta‐Cyclofenil and Its Derivatives for Potential Pet Imaging.
Authors: Zhu Hua , Huang Liliang , Xu Xiaoping , Shen Yu‐Mei
Published: March 2011

The one‐step procedure for the preparation of derivatives (V) can also be used in a radioactive labeling reaction.
ChemInform Abstract: Enantioselective, Organocatalyzed, Intramolecular Aldol Lactonizations with Keto Acids Leading to Bi‐ and Tricyclic β‐Lactones and Topology‐Morphing Transformations.
Authors: Leverett Carolyn A. , Purohit Vikram C. , Romo Daniel
Published: March 2011

An advance in the asymmetric, nucleophile‐catalyzed aldol lactonization process with keto acid substrates is described.
ChemInform Abstract: Transformation of trans‐4‐Aryl‐3‐chloro‐1‐(2‐chloroethyl)azetidin‐2‐ones into 3‐Aryl‐2‐(ethylamino)propan‐1‐ols via Intermediate 1‐(1‐Aryl‐2‐chloro‐3‐hydroxypropyl)aziridines and trans‐2‐Aryl‐3‐(hydroxymethyl)aziridines.
Authors: Mollet Karen , D'hooghe Matthias , De Kimpe Norbert
Published: March 2011

Treatment of the azetidinones (I) with an excess of LiAlH4 allows a new access to amino alcohols of type (III).
ChemInform Abstract: Asymmetric Bromolactonization Using Amino‐thiocarbamate Catalyst.
Authors: Zhou Ling , Tan Chong Kiat , Jiang Xiaojian , Chen Feng , Yeung Ying‐Yeung
Published: March 2011

The bromolactonization of unsaturated carboxylic acids gives enantioenriched γ‐lactones with high yields and enantioselectivities up to 93%.
ChemInform Abstract: Wells—Dawson Heteropolyacid Supported on Silica: A Highly Efficient Catalyst for Synthesis of 2,4,5‐Trisubstituted and 1,2,4,5‐Tetrasubstituted Imidazoles.
Authors: Karimi Ali Reza , Alimohammadi Zahra , Amini Mostafa M.
Published: March 2011

The multicomponent cyclocondensation of benzil with aromatic aldehydes, an amine and ammonium acetate (or ammonium acetate alone) is efficiently catalyzed by SiO2‐supported Wells—Dawson heteropolyacid to give the polysubstituted imidazole derivatives (IV) and (VI) in high yields.
ChemInform Abstract: Facile and Efficient Synthesis of Benzoxazoles and Benzimidazoles: The Application of Hantzsch Ester 1,4‐Dihydropyridines in Reductive Cyclization Reactions.
Authors: Xing Rui‐Guang , Li Ya‐Nan , Liu Qiang , Meng Qing‐Yuan , Li Jing , Shen Xiao‐Xia , Liu Zhengang , Zhou Bo , Yao Xiaojun , Liu Zhong‐Li
Published: March 2011

Benzoxazoles and benzimidazoles are efficiently synthesized by reductive cyclizations of ortho‐nitrophenylesters and amides in the presence of Hantzsch ester.
ChemInform Abstract: Catalytic Enantioselective 1,3‐Dipolar Cycloadditions of Nitrones with Propioloylpyrazoles and Acryloylpyrazoles Induced by Chiral π‐Cation Catalysts.
Authors: Sakakura Akira , Hori Masahiro , Fushimi Makoto , Ishihara Kazuaki
Published: March 2011

Cycloaddition reaction of propioloylpyrazoles and acryloylpyrazoles with nitrones is smoothly catalyzed by a chiral Cu(II)—naphthylalanine amide complex (CNAA) to give the isoxazolines (III), (V) and isoxazolidines (X), (XII), resp., in good yields and up to 94% optical purity.
ChemInform Abstract: Zeo‐Click Chemistry: Copper(I)—Zeolite‐Catalyzed Cascade Reaction: One‐Pot Epoxide Ring‐Opening and Cycloaddition.
Authors: Boningari Thirupathi , Olmos Andrea , Reddy Benjaram M. , Sommer Jean , Pale Patrick
Published: March 2011

Copper(I)‐modified zeolites are efficient and reusable heterogeneous catalysts for the one‐pot condensation of epoxides with sodium azide and terminal alkynes in water at room temperature.
ChemInform Abstract: A Recyclable Organocascade Reaction System: Stereoselective Precipitation of Optically Active cis‐δ‐Lactols with Quaternary Stereocenters During the Michael—Hemiacetalization Reaction.
Authors: Zhang Fanglin , Wei Mohui , Dong Junfang , Zhou Yirong , Lu Dengfu , Gong Yuefa , Yang Xiangliang
Published: March 2011

Cascade Michael addition—hemiacetalization reaction of β‐nitroethanols and α,β‐unsaturated aldehydes is smoothly catalyzed by a prolinol‐derived organocatalyst to give cis‐substituted tetrahydropyranols (III), (V) and (IX) in excellent enantioselectivity, although diastereoselectivity is only moderate.
ChemInform Abstract: Unexpected Hydrobromic Acid‐Catalyzed C—C Bond‐Forming Reactions and Facile Synthesis of Coumarins and Benzofurans Based on Ketene Dithioacetals.
Authors: Yuan Hongjuan , Wang Mang , Liu Yingjie , Wang Lili , Liu Jun , Liu Qun
Published: March 2011

HBr is found to be a unique catalyst in the title reactions.
ChemInform Abstract: Pd/C‐Catalyzed Heterocyclization During Copper‐Free Sonogashira Coupling: Synthesis of 2‐Benzylimidazo[1,2‐a]pyrimidines in Water.
Authors: Bakherad Mohammad , Keivanloo Ali , Kalantar Zahra , Jajarmi Saeideh
Published: March 2011

A Pd‐C catalyzed copper‐free Sonogashira coupling/cyclization sequence of 2‐imino‐1‐(2‐propynyl)pyrimidine offers a direct synthesis of imidazopyrimidines (V).
ChemInform Abstract: 1,2‐Diamino‐ethane‐substituted‐6,7,8,9‐tetrahydro‐5H‐pyrimido [4,5‐d]azepines as TRPV1 Antagonists with Improved Properties.
Authors: Lebsack Alec D. , et al. et al.
Published: March 2011

Based on a previously identified lead structure title compounds (XI) are synthesized and evaluated for improved physicochemical and pharmacokinetic properties while maintaining TRPV1 antagonist activity.
ChemInform Abstract: Design and Synthesis of Cyclic Sulfonamides and Sulfamates as New Calcium Sensing Receptor Agonists.
Authors: Kiefer Lionel , Gorojankina Tatiana , Dauban Philippe , Faure Helene , Ruat Martial , Dodd Robert H.
Published: March 2011

The synthetic strategy used is based on imposing conformational restrictions to the first calcimimetic family previously synthesized.
ChemInform Abstract: 2′‐Deoxy‐2′‐α‐fluoro‐2′‐β‐C‐methyl 3′,5′‐Cyclic Phosphate Nucleotide Prodrug Analogues as Inhibitors of HCV NS5B Polymerase: Discovery of PSI‐352938.
Authors: Reddy P. Ganapati , et al. et al.
Published: March 2011

The title compound (I) exhibits 100‐fold higher potency than the parent nucleoside.
ChemInform Abstract: Highly Brominated Metabolites from Marine Red Alga Laurencia similis Inhibit Protein Tyrosine Phosphatase 1B.
Authors: Qin Jianchun , Su Hua , Zhang Yamei , Gao Jinming , Zhu Lin , Wu Xian , Pan Hongyu , Li Xiang
Published: March 2011

Isolation and structural determination of five new highly brominated metabolites (I)—(III), as well as their inhibitory effects on protein tyrosine phosphatase 1B are described.
ChemInform Abstract: Potent and Selective 5‐LO Inhibitor Bearing Benzothiophene Pharmacophore: Discovery of MK‐5286.
Authors: Li Lianhai , Berthelette Carl , Chateauneuf Anne , Ouellet Marc , Sturino Claudio F. , Wang Zhaoyin
Published: March 2011

The synthesized substituted title benzothiophene (I) is able to serve as a novel scaffold of 5‐lipoxygenase (5‐LO) inhibitors and is selected to advance into pre‐clinical development.
ChemInform Abstract: Bulk Metallic Glass: The Smaller the Better
Authors: Kumar Golden , Desai Amish , Schroers Jan
Published: March 2011

Review: 113 refs.
ChemInform Abstract: The Molecular Path to Inorganic Materials ‐ Zinc Oxide and Beyond
Authors: Polarz Sebastian , Pueyo Carlos Lizandara , Krumm Michael
Published: March 2011

Review: 108 refs.
ChemInform Abstract: Emergence of Magnetism in Graphene Materials and Nanostructures
Authors: Yazyev Oleg V.
Published: March 2011

Review: 137 refs.
ChemInform Abstract: Recent Progress in Transition Metal Catalyzed Hydrofunctionalization of Less Activated Olefins
Authors: Yadav Jhillu , Antony Aneesh , Rao T. Srinivasa , Reddy Basi V. Subba
Published: March 2011

Review: 146 refs.
ChemInform Abstract: Alkyne Hydroamination Triggered Cyclizations: A Powerful Tool for the Construction of Biologically Important Structural Motifs
Authors: Patil Nitin T. , Singh Vipender
Published: March 2011

Review: 75 refs.
ChemInform Abstract: Asymmetric Syntheses Using Heteroarenesulfonyl Groups as a Highly Functional Protecting‐Activating Group
Authors: Nakamura Shuichi , Shibata Norio , Toru Takeshi
Published: March 2011

Review: about 50 refs.
ChemInform Abstract: Structure, Bioactivities, Biosynthetic Relationships and Chemical Synthesis of the Spirodioxynaphthalenes
Authors: Cai You‐Sheng , Guo Yue‐Wei , Krohn Karsten
Published: March 2011

Review: 112 refs.
ChemInform Abstract: Synthetic Studies Towards Kinamycin Antibiotics
Authors: Kumamoto Takuya
Published: March 2011

Review: 47 refs.
ChemInform Abstract: A Synthetic “Tour de Force”: Well‐Defined Multivalent and Multimodal Dendritic Structures for Biomedical Applications
Authors: Roeglin Lars , Lempens Edith H. M. , Meijer E. W.
Published: March 2011

Review: 88 refs.
ChemInform Abstract: Resonance Raman and Surface‐ and Tip‐Enhanced Raman Spectroscopy Methods to Study Solid Catalysts and Heterogeneous Catalytic Reactions
Authors: Kim Hacksung , Kosuda Kathryn M. , Van Duyne Richard P. , Stair Peter C.
Published: March 2011

Review: 300 refs.
Kinetics study on cnt‐supported RuKCo FTS catalyst in a fixed bed reactor
Authors: Trépanier Mariane , Dion Christopher A. Dorval , Dalai Ajay K. , Abatzoglou Nicolas
Published: March 2011

The rate of syngas (H2/CO) consumption over a RuKCo/CNT Fischer–Tropsch synthesis (FTS) catalyst was measured in a fixed bed microreactor at 210–225°C, 2–3.5 MPa, H2/CO feed molar ratios of 1–2.5, and gas hourly space velocity (GHSV) range of 2700–3600 h−1. The data have been used to model the kinetics of the FTS reactions within the range of the studied conditions. One empirical power law model and four semi‐empirical kinetic models based on Langmuir–Hinshelwood‐type equation have been evaluated. The best fitting was obtained with the equation:

similar to that proposed by Brötz et al. The estimated activation energy (E = 80–85 kJ/mol) is lower than that is reported in the literature. The validity of these results are restricted to fixed beds with the given catalyst in the tested conversion regime.
Synthesis of Furfural from Xylose by Heterogeneous and Reusable Nafion Catalysts
Authors: Lam Edmond , Majid Ehsan , Leung Alfred C. W. , Chong Jonathan H. , Mahmoud Khaled A. , Luong John H. T.
Published: March 2011

Nafion 117 has been proven as a robust and reusable heterogeneous catalyst for the dehydration of 9.1 % (w/w) xylose in dimethyl sulfoxide (DMSO) to yield 60 % furfural in 2 h at 150 °C. The catalytic high activity promoted shorter reaction times to limit the formation of side‐products which otherwise would lead to decreased yields. Within the allowable operating temperature range of Nafion (125 to 175 °C), the reaction was kinetically controlled. In corroboration with AFM and SEM imaging, ATR–FTIR confirmed that the Nafion catalytic activity remained unchanged after 15 repeated uses. With excellent chemical and thermal stability under the conditions for xylose dehydration compared to existing solid acid catalysts, this reusable Nafion system could be a step towards the more economical production of furfural from renewable biomass, an intermediate chemical for the preparation of value‐added chemicals.
Methylated [(benzene)(1,3‐butadiene)Ru0] Derivatives as Novel MOCVD Precursors with Favorable Properties
Authors: Jipa Ilona , Siddiqi M. Aslam , Siddiqui Rehan A. , Atakan Burak , Marbach Hubertus , Cremer Till , Maier Florian , Steinrück Hans‐Peter , Danova Katia , Popovska Nadejda , Heinemann Frank W. , Zenneck Ulrich
Published: March 2011

[(Benzene)(2‐methyl‐1,3‐butadiene)Ru0] (1), [(benzene)(2,3‐dimethyl‐1,3‐butadiene)Ru0] (2), and [(2,3‐dimethyl‐1,3‐butadiene)(toluene)Ru0] (3) are prepared and tested as new metal‐organic (MO) ruthenium precursor complexes with favorable deposition properties for the CVD of thin ruthenium films. X‐ray diffraction (XRD) studies of single crystals of the complexes are characteristic for true Ru0 π‐complexes without molecular structure peculiarities or significant intermolecular interactions in the solid state, which can hinder undecomposed evaporation. Differential thermal analysis (DTA) and vapor pressure data qualify the compounds as almost ideal MOCVD precursors. Thin ruthenium films are deposited successfully on silicon wafers at substrate temperatures between 200 and 400 °C in a nitrogen gas atmosphere. X‐ray photoelectron spectroscopy (XPS), four‐point probe conductivity measurements, and atomic force microscopy (AFM) are used to characterize the films. All films consist of polycrystalline metallic ruthenium with a low surface roughness.
Adenosquamous carcinoma of the lung diagnosed by cytology?: A diagnostic dilemma
Authors: Shelton David A. , Rana Durgesh N. , Holbrook Miles , Taylor Paul , Bailey Simon
Published: March 2011

Adenosquamous cell carcinomas of the lung are rare tumours and are associated with a poor prognosis compared to other non‐small cell carcinomas. We report a case of a solitary lung carcinoma evaluated by bronchial brush and lavage cytology, bronchial biopsy and pleural fluid cytology. Cytological assessment of the pleural fluid demonstrated non‐small cell carcinoma and immunohistochemical staining confirmed a metastatic lung adenocarcinoma. The bronchial brush and lavage specimens, however, demonstrated the cytomorphological features of squamous cell carcinoma, which was confirmed by the bronchial biopsy.

The finding of a mixed squamous and glandular component predicts a poor prognosis for this patient. The identification of a squamous component with the non‐small cell carcinoma is important as this excludes the patient from anti‐VEGF monoclonal antibody treatment due to the increased risk of haemorrhage. Diagn. Cytopathol. 2012. © 2011 Wiley Periodicals, Inc.
One‐Pot Synthesis of Carboxyl‐Functionalized Rare Earth Fluoride Nanocrystals with Monodispersity, Ultrasmall Size and Very Bright Luminescence
Authors: Wu Xuejin , Zhang Qingbin , Wang Xin , Yang Hui , Zhu Yimin
Published: March 2011

We demonstrated a straightforward approach to the synthesis of ultrasmall, monodisperse and carboxyl‐functionalized rare earth (RE) fluoride nanocrystals via a one‐pot reaction by introducing poly(acrylic acid) (PAA) as a coordination agent and surfactant. The morphologies, crystal structure, surface groups, and luminescent properties of the PAA‐capped RE fluoride nanocrystals were investigated in detail by TEM, FTIR, and photoluminescence spectroscopy. The obtained RE fluoride nanocrystals were ultrasmall in size, monodisperse, and highly crystalline. FTIR spectra confirmed that the PAA molecules strongly coordinated to the surface of the nanocrystals, which allows the formation of transparent colloidal aqueous solutions. Successful coating of the LaF3 shell on the NaCeF4:Tb3+ nanocrystals can increase the luminescence efficiency and lifetimes of Tb3+ ions relative to the pure NaCeF4:Tb3+ core. This synthesis procedure could become a versatile approach for the straightforward synthesis of carboxyl‐functionalized nanocrystals with ultrasmall size and monodispersity.
Understanding the Reactivity of Acyl Anion Equivalents: The Epoxide Ring Opening Case
Authors: Eger Wilhelm A. , Grange Rebecca L. , Schill Heiko , Goumont Régis , Clark Timothy , Williams Craig M.
Published: March 2011

Acyl anion equivalents (umpolung) are the practitioner's first choice en route to 1,3‐hydroxy keto compounds from epoxides. Why? This investigation evaluates computationally and experimentally the reactivity of a near comprehensive range of acyl anion equivalents using epoxide ring opening as a test vehicle. Reactivity understanding, reactivity order, surprise failures in performance, along with unprecedented, but far from superior, reactivity of TosMIC is presented for the first time.
Electrochemical Studies and Square Wave Voltammetric Determination of S‐[(2‐Guanidino‐thiazol‐4‐yl)methyl]isothiourea hydrochloride and 2‐Guanidino‐1,3‐thiazole
Authors: Skrzypek Sławomira , Lewkowski Jarosław
Published: March 2011

S‐[(2‐Guanidino‐thiazol‐4‐yl)methyl]isothiourea hydrochloride (GTAMITU) and 2‐guanidino‐1,3‐thiazole (GTA) were studied at hanging mercury drop electrode under conditions of square‐wave voltammetry and in the function of the electrode potential for different adsorbate concentrations. The experimental data of adsorption were obtained from the measurement of differential capacity of the double layer, the measurement of zero charge potential and surface tension at the zero charge potential. The received results point to the adsorption of molecules directly with the guanidine group to the mercury surface and suggest that the molecules are not placed flatly on the mercury surface. This kind of arrangement of molecules enables electron transfer, which is the basis of their electroactivity and causes the compounds to act as electrocatalysts. New adsorptive catalytic methods for voltammetric (SW AdSV) determination of GTAMITU and GTA were developed. The dependence of the peak current on pH, buffer concentration, and nature of the buffer were studied. The best results according to the shape and sensitivity of the peak were recorded in citrate buffer at pH 2.0 for GTAMITU and in phosphate–citrate buffer at pH 2.96 for GTA. This electroanalytical procedure enabled to determine GTAMITU and GTA in the concentration range 5×10−8–4×10−7 mol L−1 and 8×10−7–8×10−6 mol L−1 respectively. Precision, repeatability and accuracy of the method were checked. The detection and quantification limits were found to be 1.3×10−8 and 4.4×10−8 mol L−1 for GTAMITU and 2.6×10−7 and 8.0×10−7 mol L−1 for GTA respectively.
Disease model distortion in association studies
Authors: Vukcevic Damjan , Hechter Eliana , Spencer Chris , Donnelly Peter
Published: March 2011

Most findings from genome‐wide association studies (GWAS) are consistent with a simple disease model at a single nucleotide polymorphism, in which each additional copy of the risk allele increases risk by the same multiplicative factor, in contrast to dominance or interaction effects. As others have noted, departures from this multiplicative model are difficult to detect. Here, we seek to quantify this both analytically and empirically. We show that imperfect linkage disequilibrium (LD) between causal and marker loci distorts disease models, with the power to detect such departures dropping off very quickly: decaying as a function of r4, where r2 is the usual correlation between the causal and marker loci, in contrast to the well‐known result that power to detect a multiplicative effect decays as a function of r2. We perform a simulation study with empirical patterns of LD to assess how this disease model distortion is likely to impact GWAS results. Among loci where association is detected, we observe that there is reasonable power to detect substantial deviations from the multiplicative model, such as for dominant and recessive models. Thus, it is worth explicitly testing for such deviations routinely. Genet. Epidemiol. 35: 278‐290, 2011.  © 2011 Wiley‐Liss, Inc.
Creating probabilistic maps of the face network in the adolescent brain: A multicentre functional MRI study
Authors: Tahmasebi Amir M. , Artiges Eric , Banaschewski Tobias , Barker Gareth J. , Bruehl Ruediger , Büchel Christian , Conrod Patricia J. , Flor Herta , Garavan Hugh , Gallinat Jürgen , Heinz Andreas , Ittermann Bernd , Loth Eva , Mareckova Klara , Martinot Jean‐Luc , Poline Jean‐Baptiste , Rietschel Marcella , Smolka Michael N. , Ströhle Andreas , Schumann Gunter , Paus Tomáš ,   The IMAGEN Consortium
Published: March 2011

Large‐scale magnetic resonance (MR) studies of the human brain offer unique opportunities for identifying genetic and environmental factors shaping the human brain. Here, we describe a dataset collected in the context of a multi‐centre study of the adolescent brain, namely the IMAGEN Study. We focus on one of the functional paradigms included in the project to probe the brain network underlying processing of ambiguous and angry faces. Using functional MR (fMRI) data collected in 1,110 adolescents, we constructed probabilistic maps of the neural network engaged consistently while viewing the ambiguous or angry faces; 21 brain regions responding to faces with high probability were identified. We were also able to address several methodological issues, including the minimal sample size yielding a stable location of a test region, namely the fusiform face area (FFA), as well as the effect of acquisition site (eight sites) and scanner (four manufacturers) on the location and magnitude of the fMRI response to faces in the FFA. Finally, we provided a comparison between male and female adolescents in terms of the effect sizes of sex differences in brain response to the ambiguous and angry faces in the 21 regions of interest. Overall, we found a stronger neural response to the ambiguous faces in several cortical regions, including the fusiform face area, in female (vs. male) adolescents, and a slightly stronger response to the angry faces in the amygdala of male (vs. female) adolescents. Hum Brain Mapp, 2012. © 2011 Wiley Periodicals, Inc.
External light guidance for percutaneous dilatational tracheotomy
Authors: El‐Sayed Ivan H. , Ho James E. , Eisele David W.
Published: March 2011

Background

Percutaneous dilatational tracheotomy (PDT) is considered a safe technique; however, there is still room for improvement. We present our initial experience with an external white light guide to position the endotracheal tube and guide needle placement during PDT.

Methods

This is a retrospective series of 15 consecutive patients undergoing external light–guided PDT. A white light source was placed on the anterior trachea wall externally and the transmitted light was identified in the tracheal lumen with a bronchoscopic to predict the needle entrance point.

Results

The transmitted light was rapidly identified in all 15 patients, facilitated endotracheal tube tip placement in the subglottis in approximately 10 seconds in 13 of 15 patients, and predicted needle penetration into the trachea within 1 to 2 mm of the external light in all patients.

Conclusions

External light guidance facilitates rapid, accurate placement of the needle through the tracheal wall and can reduce surgeon anxiety, especially in teaching situations. © 2011 Wiley Periodicals, Inc. Head Neck, 2011
TP53 Mutational signature for aristolochic acid: an environmental carcinogen
Authors: Moriya Masaaki , Slade Neda , Brdar Branko , Medverec Zvonimir , Tomic Karla , Jelaković Bojan , Wu Lin , Truong Sim , Fernandes Andrea , Grollman Arthur P.
Published: March 2011

This study was designed to establish the TP53 mutational spectrum of aristolochic acid (AA), examined in the context of endemic (Balkan) nephropathy, an environmental disease associated with transitional cell (urothelial) carcinomas of the upper urinary tract (UUC). Tumor tissue was obtained from residents of regions in Bosnia, Croatia and Serbia where endemic nephropathy has been prevalent for over 50 years. Fifty‐nine TP53 mutations were detected in 42 of the 97 tumors analyzed. Mutational spectra were dominated by A:T to T:A transversions with the mutated adenines located almost exclusively on the nontranscribed strand. This marked strand bias is attributed to selective processing of aristolactam‐dA adducts by transcription‐coupled nucleotide excision repair. Hotspots for A:T to T:A mutations include codons 131 and 179 and the 5′‐AG acceptor splice site of intron 6. The unique TP53 mutational signature for AA identified in this study can be used to explore the hypothesis that botanical products containing this human carcinogen and nephrotoxin are responsible, in part, for the high prevalence of UUC and chronic renal disease in countries where Aristolochia herbal remedies traditionally have been used for medicinal purposes.
Gene expression profiling of pituitary melanotrope cells during their physiological activation
Authors: Kuribara Miyuki , van Bakel Nick H.M. , Ramekers Dyan , de Gouw Daan , Neijts Roel , Roubos Eric W. , Scheenen Wim J.J.M. , Martens Gerard J.M. , Jenks Bruce G.
Published: March 2011

The pituitary melanotrope cells of the amphibian Xenopus laevis are responsible for the production of the pigment‐dispersing peptide α‐melanophore‐stimulating hormone, which allows the animal to adapt its skin color to its environment. During adaptation to a dark background the melanotrope cells undergo remarkable changes characterized by dramatic increases in cell size and secretory activity. In this study we performed microarray mRNA expression profiling to identify genes important to melanotrope activation and growth. We show a strong increase in the expression of the immediate early gene (IEG) c‐Fos and of the brain‐derived neurotrophic factor gene (BDNF). Furthermore, we demonstrate the involvement of another IEG in the adaptation process, Nur77, and conclude from in vitro experiments that the expression of both c‐Fos and Nur77 are partially regulated by the adenylyl cyclase system and calcium ions. In addition, we found a steady up‐regulation of Ras‐like product during the adaptation process, possibly evoked by BDNF/TrkB signaling. Finally, the gene encoding the 105‐kDa heat shock protein HSPh1 was transiently up‐regulated in the course of black‐background adaptation and a gene product homologous to ferritin (ferritin‐like product) was >100‐fold up‐regulated in fully black‐adapted animals. We suggest that these latter two genes are induced in response to cellular stress and that they may be involved in changing the mode of mRNA translation required to meet the increased demand for de novo protein synthesis. Together, our results show that microarray analysis is a valuable approach to identify the genes responsible for generating coordinated responses in physiologically activated cells. J. Cell. Physiol. 227: 288–296, 2012. © 2011 Wiley Periodicals, Inc.
Zinc Oxide Based Coatings for the UV‐Protection of Wood for Outdoor Applications
Authors: Weichelt Franziska , Beyer Mario , Emmler Rico , Flyunt Roman , Beyer Evelin , Buchmeiser Michael
Published: March 2011

Summary: Nano‐sized zinc oxide (ZnO) was chosen as a suitable candidate for the UV‐protection of coatings. ZnO‐based acrylate coatings were applied to polycarbonate plates, glass plates and impregnated wood. Coated samples were artificially weathered (Xenon test) for at least 1500 hours and studied with regards to their optical and mechanical properties, such as color shifts (yellowing), as well as to changes in brightness, transparency or hydrophobicity. The prepared wood coatings showed reduced yellowing and improved optical properties.
LDH as Nanofiller: Organic Modification and Dispersion in Polymers
Authors: Costa F.R. , Leuteritz A. , Meinl J. , Wagenknecht U. , Heinrich G.
Published: March 2011

Summary: Layered double hydroxide (LDH) is a relatively new class of layered crystalline clay materials to be used as nanofiller in various polymer matrices. We report here the organic modification of LDH by anionic surfactants having different sizes and functionalities. Subsequently, their dispersion in polymer is discussed and finally the characteristics of the polymer/LDH nanocomposites are investigated. LDH has been modified using regeneration method, which shows that irrespective of size and functionality of the anionic surfactant, organic modification can be carried out efficiently. However, it has been observed that alkyl sulfonate are more efficiently intercalated within LDH layers than other surfactants giving well defined crystal structure of the modified LDH. These modified LDH, when dispersed in polymers like maleic anhydride grafted polyethylene shows that not only the size of the surfactant, but also the functionality of the surfactant influences their dispersion in a non polar polymer matrix.
Ligand Efficiency Indices (LEIs): More than a Simple Efficiency Yardstick
Authors: Abad‐Zapatero Cele , Blasi Daniel
Published: March 2011

The concept of ligand efficiency and the usage of ligand efficiency values to assess the quality of fragments and compounds is becoming more accepted in the practice of medicinal chemistry. This is particularly true as it refers to the efficiency of ligands per unit size (i.e., binding affinity/number of non‐hydrogen atoms or binding affinity/MW). The use of the Ligand Efficiency Indices (LEIs) as variables for a Cartesian mapping of chemico‐biological space, the concept of AtlasCBS, has been presented in a recent publication with some initial drug‐discovery applications. In this communication, we present additional applications of the concept in three domains of drug discovery: i) analyze and compare the content of databases: inhibitors vs. drugs; ii) polypharmacology; and iii) applications to Fragment‐Based strategies. We suggest that the combined use of LEIs in a Cartesian representation of Chemico‐Biological Space (AtlasCBS) could be a useful tool in various aspects of drug‐discovery in the future.