bluuebunny/crossref_metadata_2025 huggingface dataset:
Deriving global flood hazard maps of fluvial floods through a physical model cascade
Authors: Pappenberger F. , Dutra E. , Wetterhall F. , Cloke H.
Published: May 2012

Abstract. Global flood hazard maps can be used in the assessment of flood risk in a number of different applications, including (re)insurance and large scale flood preparedness. Such global hazard maps can be generated using large scale physically based models of rainfall-runoff and river routing, when used in conjunction with a number of post-processing methods. In this study, the European Centre for Medium Range Weather Forecasts (ECMWF) land surface model is coupled to ERA-Interim reanalysis meteorological forcing data, and resultant runoff is passed to a river routing algorithm which simulates floodplains and flood flow across the global land area. The global hazard map is based on a 30 yr (1979–2010) simulation period. A Gumbel distribution is fitted to the annual maxima flows to derive a number of flood return periods. The return periods are calculated initially for a 25 × 25 km grid, which is then reprojected onto a 1 × 1 km grid to derive maps of higher resolution and estimate flooded fractional area for the individual 25 × 25 km cells. Several global and regional maps of flood return periods ranging from 2 to 500 yr are presented. The results compare reasonably to a benchmark data set of global flood hazard. The developed methodology can be applied to other datasets on a global or regional scale.
Comment on "Ultra Low Frequency (ULF) European multi station magnetic field analysis before and during the 2009 earthquake at L'Aquila regarding regional geotechnical information" by Prattes et al. (2011)
Authors: Masci F.
Published: May 2012

Abstract. Prattes et al. (2011) report ULF magnetic anomalous signals claiming them to be possibly precursor of the 6 April 2009 MW = 6.3 L'Aquila earthquake. This comment casts doubts on the possibility that the observed magnetic signatures could have a seismogenic origin by showing that these pre-earthquake signals are actually part of normal global geomagnetic activity.
The link between the Barents Sea and ENSO events reproduced by NEMO model
Authors: Stepanov V. N. , Zuo H. , Haines K.
Published: May 2012

Abstract. An analysis of observational data in the Barents Sea along a meridian at 33°30´ E between 70°30´ and 72°30´ N has reported a negative correlation between El Niño/La Niña-Southern Oscillation (ENSO) events and water temperature in the top 200 m: the temperature drops about 0.5 °C during warm ENSO events while during cold ENSO events the top 200 m layer of the Barents Sea is warmer. Results from 1 and 1/4-degree global NEMO models show a similar response for the whole Barents Sea. During the strong warm ENSO event in 1997–1998 an anticyclonic atmospheric circulation is settled over the Barents Sea instead of a usual cyclonic circulation. This change enhances heat loses in the Barents Sea, as well as substantially influencing the Barents Sea inflow from the North Atlantic, via changes in ocean currents. Under normal conditions along the Scandinavian peninsula there is a warm current entering the Barents sea from the North Atlantic, however after the 1997–1998 event this current is weakened. During 1997–1998 the model annual mean temperature in the Barents Sea is decreased by about 0.8 °C, also resulting in a higher sea ice volume. In contrast during the cold ENSO events in 1999–2000 and 2007–2008 the model shows a lower sea ice volume, and higher annual mean temperatures in the upper layer of the Barents Sea of about 0.7 °C. An analysis of model data shows that the Barents Sea inflow is the main source for the variability of Barents Sea heat content, and is forced by changing pressure and winds in the North Atlantic. However, surface heat-exchange with atmosphere can also play a dominant role in the Barents Sea annual heat balance, especially for the subsequent year after ENSO events.
Prevalence of CGG expansions of the FMR1 gene in a US population‐based sample
Authors: Seltzer Marsha Mailick , Baker Mei Wang , Hong Jinkuk , Maenner Matthew , Greenberg Jan , Mandel Daniel
Published: May 2012

The primary goal of this study was to calculate the prevalence of the premutation of the FMR1 gene and of the “gray zone” using a population‐based sample of older adults in Wisconsin (n = 6,747 samples screened). Compared with past research, prevalence was relatively high (1 in 151 females and 1 in 468 males for the premutation and 1 in 35 females and 1 in 42 males for the gray zone as defined by 45–54 CGG repeats). A secondary study goal was to describe characteristics of individuals found to have the premutation (n = 30, 7 males and 23 females). We found that premutation carriers had a significantly higher rate of divorce than controls, as well as higher rates of symptoms that might be indicative of fragile X‐associated tremor ataxia syndrome (FXTAS; numbness, dizziness/faintness) and fragile X primary ovarian insufficiency (FXPOI; age at last menstrual period). Although not statistically significant, premutation carriers were twice as likely to have a child with disability. © 2012 Wiley Periodicals, Inc.
Magnetic transitions in strong coupling expansions for nearly degenerate states
Authors: Frésard R. , Hackenberger Ch. , Kopp T.
Published: May 2012

A strong coupling expansion for a two‐band Hubbard model on two sites with nearly degenerate states is considered. A comparative analysis is performed for different schemes of perturbation theory which are applicable to systems with nearly degenerate states. A fourth order approach which builds on a four‐dimensional low‐energy subspace with nearly degenerate states captures accurately the transition from an antiferromagnetic to a ferromagnetic ground state at large on‐site Coulomb interaction.
Microstructure and mechanical properties of a polyethylene/polydimethylsiloxane composite prepared using supercritical carbon dioxide
Authors: Zhu Rui , Hoshi Toru , Muroga Yoshio , Hagiwara Toshiki , Yano Shoichiro , Sawaguchi Takashi
Published: May 2012

A polymer composite of polyethylene (PE) and polydimethylsiloxane (PDMS) was prepared using supercritical carbon dioxide despite the two polymers usually being immiscible and possessing a phase‐separated morphology. This article reports in detail the preparation, microstructure, crystallinity, and mechanical properties of the resulting PE/PDMS composite. The formation mechanism of the PE/PDMS composite consisted of supercritical impregnation of an octamethylcyclotetrasiloxane (D4) monomer and an initiator into a PE substrate followed by in situ polymerization within the substrate. Differential scanning calorimetry, wide‐angle X‐ray diffraction, and small‐angle X‐ray scattering measurements showed that PE and PDMS were blended at the nanometer level. The PDMS generated in the amorphous region of PE did not affect its crystallinity. Dynamic viscoelastic analyses and tensile tests were used to measure the mechanical properties of the composites including storage and Young's modulus, fracture stress, and strain. These properties were found to depend on the composition of the composite. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Properties of organo‐clay/natural rubber nanocomposites: Effects of organophilic modifiers
Authors: Hrachová Jana , Komadel Peter , Jochec‐Mošková Daniela , Krajči Juraj , Janigová Ivica , Šlouf Miroslav , Chodák Ivan
Published: May 2012

The effect of various modifiers on the structure and properties of clay/natural rubber nanocomposites are investigated with the aim to evaluate the effect of size and structure of the modifier. Nanocomposites are prepared by melt intercalation method. Mechanical properties of the cured rubber containing nanoclay are compared with the reference compound without the filler. No improvement of mechanical properties is observed for small organic cations; however, stress and strain at break of clay/rubber nanocomposites increase with rising number of octyl chains in the interlayer spaces of organo‐clays. Concerning organo‐cations with the same number of carbon atoms, more effective are the modifiers with several shorter carbon chains compared to those with one long chain. The composites exhibit hybrid structure of nanocomposite and microcomposite as revealed by X‐ray powder diffraction (XRD), transmission electron microscopy (TEM), and scanning electron microscopy (SEM). The details of the structure are supported by DMTA and hysteresis measurements. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
“Pore/bead” membrane for rechargeable lithium ion batteries
Authors: Su Yuezeng , Shan Feng , Li Zhiming , Wang Xinling
Published: May 2012

A special “pore/bead” membrane was prepared with a mesoporous inorganic filler (MCM‐41) and a P(VDF‐HFP) binder. The special “pore/bead” structure of the MCM‐41 filler not only enhanced the puncture strength of the membrane but also improved its ionic conductivity. The puncture strength of the dried “pore/bead” membrane (MCM‐41 : P(VDF‐HFP) = 1 : 1.5) was 18 N, and showed a slight decrease (16 N) after the membrane was wetted by liquid electrolyte. Additionally, the composite membrane showed excellent thermal dimensional stability. The composite membrane could be activated by adding 1M LiClO4‐EC/DMC (1 : 1 by volume). The activated membrane displayed a high ionic conductivity about 3.4 × 10−3 S cm−1 at room temperature. Its electrochemical stability window was up to 5.3 V vs. Li/Li+, indicating that it was very suitable for lithium‐ion battery application. The battery assembled using the composite electrolyte also showed reasonably good high‐rate performance. The approach of preparing a “pore/bead” membrane provides a new avenue for improving both the conductivity and the mechanical strength of polymer electrolytes for lithium batteries. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Preparation of anionic ion exchange latex particles via heteroaggregation
Authors: Jeong Han Su , Daniels Eric S. , David Sudol E. , Dimonie Victoria L. , Klein Andrew
Published: May 2012

To prepare relatively large negatively charged polymer particles in a size range from 0.3 μm to 0.5 μm, having high surface charge densities, the heteroaggregation of small (50–100 nm), highly charged (185 and 421 μeq/g) anionic polystyrene particles onto the surface of larger (317–466 nm) poly(vinylbenzyl choride)‐based cationic (10, 614, and 830 μeq/g) particles was carried out. As a result, particles with different surface charges, having a core‐shell structure, were successfully prepared. First, aggregated particles were formed via heteroaggregation of the lowest surface charge density anionic particles (185 μeq/g) with the lowest surface charge density cationic particles (10 μeq/g). However, the anionic particles in the shell layer desorbed with time owing to the relatively weak interaction between the two particles. Second, aggregated particles comprised of the highest surface charge density cationic (830 μeq/g) and anionic latex particles (421 μeq/g) were formed. However, to prepare a stable system, an excess of the small anionic particles was required, leaving a large number of small particles present in the aqueous phase, which proved difficult to remove. Finally, aggregated particles were formed by heteroaggregation of cationic particles with an intermediate surface charge density (614 μeq/g) with the highest surface charge anionic particles (421 μeq/g). As a result, not only were core‐shell particles formed, but few free small anionic particles remained in the aqueous phase. In this article, the preparation and characterization of each of these aggregates are discussed in terms of particle size, morphology, and extent of incorporation of the functional groups. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Synthesis and anticorrosion properties of poly(2,3‐dimethylaniline) doped with phosphoric acid
Authors: Ma Li , Huang Chao‐Qun , Gan Meng‐Yu
Published: May 2012

Poly(2,3‐dimethylaniline) (P(2,3‐DMA)) was synthesized chemically by using phosphoric acid (H3PO4) as protonic acid. The optimum ratio for n(H3PO4)/n(2,3‐DMA)/n(APS) was 2.5/1/2, and the optimum temperature was 30°C. The spectra of ultraviolet‐visible and infrared demonstrate that the structure of P(2,3‐DMA) was similar with polyaniline (PANI) except for the 2,3‐ortho‐substitute methyl. The result of X‐ray diffraction and solubility analysis indicate that owing to the 2,3‐ortho‐substitute benzene ring, the P(2,3‐DMA) has poorly partial crystallinity and better solubility. In addition, the anticorrosion property of P(2,3‐DMA) was better than PANI. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Full factorial design‐of‐experiments for preparation of crosslinked dextran microspheres
Authors: Kenari Hamed Salimi , Imani Mohammad , Nodehi Azizollah
Published: May 2012

This work describes full factorial design‐of‐experiment methodology for exploration of effective parameters on physical properties of dextran microspheres prepared via an inverse emulsion (W/O) technique. Microspheres were prepared by chemical crosslinking of dextran dissolved in internal phase of the emulsion using epichlorohydrin. The input parameters were dextran concentration in the aqueous phase, crosslinking ratio, and concentrations of sodium hydroxide and span 80 as the reaction catalyst and surfactant, respectively. Chemical structure of the resulting microspheres was analyzed spectroscopically using Fourier‐transform infrared technique. Final decomposition temperature, mean particle size and its distribution and equilibrium swelling ratio were selected as output responses. Microspheres with smooth surface were obtained according to scanning electron micrographs. It was found that an increase in dextran concentration in the aqueous internal phase increases mean particle diameter of the resulting microspheres, significantly. Moreover, water uptake capacity for the microspheres was dependent on both the dextran concentration and crosslinking ratio. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Detail‐feature‐preserving surface reconstruction
Authors: Zhao Xu , Zhou Zhong , Duan Ye , Wu Wei
Published: May 2012

In this paper, we propose a feature‐preserving surface reconstruction method from sparse noisy 3D measurements such as range scanning or passive multiview stereo. In contrast to earlier methods, we define a novel type of explicit 3D filter—regularized weighted least squares filter—to characterize the detail features such as surface wrinkles and sharp features. To account for noise, we rasterize input‐oriented points into a probabilistic volume (base volume) and then create a guidance volume by Gaussian filtering. Both the base volume and the guidance volume are further filtered by regularized weighted least squares filter to detect and recover detail features. After the two‐stage filtering, a global minimal surface is computed by graph cut and meshed as a geometric model. Experimental results on various datasets show that our method is robust to noise, outliers, and missing parts, which makes it more suitable to fit indoor/outdoor multiview stereo data. Unlike other methods, our method can completely recover scene structures and preserve detail features from noisy point samples. Copyright © 2012 John Wiley & Sons, Ltd.
DNA Interaction of the CcrM DNA Methyltransferase: A Mutational and Modeling Study
Authors: Albu Razvan F. , Zacharias Martin , Jurkowski Tomasz P. , Jeltsch Albert
Published: May 2012

Caulobacter crescentus CcrM is a DNA‐(adenine N6)‐methyltransferase that methylates adenine in the sequence GANTC with high specificity. To investigate its mechanism of DNA recognition, we used the crystal structure of a related methyltransferase (M1.MboII, which modifies GAAGA) as a starting point, and docked into it a DNA substrate to identify the protein regions that approach the DNA. After alignment of CcrM and M1.MboII, we identified four candidate regions in CcrM to contain residues involved in DNA recognition. We mutated 20 amino acid residues within these regions, purified the CcrM variants, and determined their DNA‐binding and catalytic activity on a cognate GANTC substrate and on nine near‐cognate substrates, each of which contained a single base‐pair substitution in the recognition sequence. Altogether, we identified four residues in two of the regions, mutations of which resulted in a strong (>100‐fold) reduction of methylation activity. Our data show that DNA recognition by CcrM is a cooperative process, because disruption of critical contacts led to loss of catalytic activity but not to a relaxation in specificity. In addition, we identified a change in the readout of the fifth base pair in the GANTC sequence with two other CcrM variants that showed smaller reductions in overall activity. Based on this and the sequence alignment of CcrM with other DNA methyltransferases of same or related recognition sequence, we propose roles for these two regions in DNA recognition by CcrM.
Design and Function of Pre‐organised Outer‐Sphere Amidopyridyl Extractants for Zinc(II) and Cobalt(II) Chlorometallates: The Role of CH Hydrogen Bonds
Authors: Ellis Ross J. , Chartres Jy , Henderson David K. , Cabot Rafel , Richardson Patricia R. , White Fraser J. , Schröder Martin , Turkington Jennifer R. , Tasker Peter A. , Sole Kathryn C.
Published: May 2012

Four new sterically hindered pyridines, L1–L4‐containing amido substituents at the 2‐position act as efficient solvent extractants for [CoCl4]2− or [ZnCl4]2− from acidic chloride solutions through protonation of the pyridino N‐centre to form the neutral outer‐sphere complexes [(LH)2MCl4]. These ionophores show very high selectivity for chlorometallate anions over chloride ion and are readily stripped to liberate the free‐metal chlorides without the formation of inner‐sphere complexes [ML2Cl2]. Single‐crystal X‐ray structure determinations of [(L2H)2CoCl4] and [(L2H)2ZnCl4] (L2=2‐(4,6‐di‐tert‐butylpyridin‐2‐yl)‐N,N′‐dihexylmalonamide) coupled with 1H NMR spectroscopy and DFT calculations on L2H+ and other complexes of [ZnCl4]2− confirm that the pyridinium NH group does not address the outer co‐ordination sphere of the metallanion, but rather forms a hydrogen bond to the pendant amide groups and thus pre‐organizes the ligand to present both CH and amido NH hydrogen‐bond donors to the [MCl4]2− ions. The selectivity for chlorometallates over chloride ions shown by this class of extractants arises from their ability to present several polarized CH units towards the charge‐diffuse ions [MCl4]2−, whereas the smaller, “harder” chloride anion prefers to be associated with the amido NH hydrogen‐bond donors.
Revised Molecular Basis of the Promiscuous Carboxylic Acid Perhydrolase Activity in Serine Hydrolases
Authors: Yin DeLu (Tyler) , Kazlauskas Romas J.
Published: May 2012

Several serine hydrolases catalyze a promiscuous reaction: perhydrolysis of carboxylic acids to form peroxycarboxylic acids. The working hypothesis is that perhydrolases are more selective than esterases for hydrogen peroxide over water. In this study, we tested this hypothesis, and focused on L29P‐PFE (Pseudomonas fluorescens esterase), which catalyzes perhydrolysis of acetic acid 43‐fold faster than wild‐type PFE. This hypothesis predicts that L29P‐PFE should be approximately 43‐fold more selective for hydrogen peroxide than wild‐type PFE, but experiments show that L29P‐PFE is less selective. The ratio of hydrolysis to perhydrolysis of methyl acetate at different concentrations of hydrogen peroxide fit a kinetic model for nucleophile selectivity. L29P‐PFE (β0=170 M−1) is approximately half as selective for hydrogen peroxide over water than wild‐type PFE (β0=330 M−1), which contradicts the working hypothesis. An alternative hypothesis is that carboxylic acid perhydrolases increase perhydrolysis by forming the acyl‐enzyme intermediate faster. Consistent with this hypothesis, the rate of acetyl‐enzyme formation, measured by 18O‐water exchange into acetic acid, was 25‐fold faster with L29P‐PFE than with wild‐type PFE, which is similar to the 43‐fold faster perhydrolysis with L29P‐PFE. Molecular modeling of the first tetrahedral intermediate (Td1) suggests that a closer carbonyl group found in perhydrolases accepts a hydrogen bond from the leaving group water. This revised understanding can help design more efficient enzymes for perhydrolysis and shows how subtle changes can create new, unnatural functions in enzymes.
ChemInform Abstract: The Gold‐Rich Indide Eu5Au17.7In4.3 and Its Relation with the Structures of SrAu4.76In1.24 and BaLi4.
Authors: Muts Ihor , Rodewald Ute Ch. , Zaremba Vasyl' I. , Pavlosyuk Orest
Published: May 2012

Eu5Au17.7In4.3 is synthesized from the elements (sealed Ta ampule, Ar, 1500 K for 1 min, 900 K for 4 h) and characterized by powder and single crystal XRD.
ChemInform Abstract: SnSe2 Quantum Dot Sensitized Solar Cells Prepared Employing Molecular Metal Chalcogenide as Precursors.
Authors: Yu Xuechao , Zhu Jun , Zhang Yaohong , Weng Jian , Hu Linhua , Dai Songyuan
Published: May 2012

(N2H4)3 (N2H5)4Sn2Se6 complexes, synthesized by dissolving elemental tin and selenium in hydrazine under ambient conditions, are used as precursors for SnSe2 deposition on TiO2 nanocrystalline porous films.
ChemInform Abstract: Copper(I) Catalyzed Asymmetric 1,2‐Addition of Grignard Reagents to α‐Methyl Substituted α,β‐Unsaturated Ketones.
Authors: Madduri Ashoka V. R. , Minnaard Adriaan J. , Harutyunyan Syuzanna R.
Published: May 2012

The first catalytic enantioselective 1,2‐addition of Grignard reagents (II), (V) and (VIII) to ketones (I), (IV), (VII) and (X) is reported.
ChemInform Abstract: Strecker‐Type Reaction of Nitrones Using Cyanohydrin.
Authors: Sakai Takahiro , Soeta Takahiro , Inomata Katsuhiko , Ukaji Yutaka
Published: May 2012

Treatment of nitrones (I) with acetone cyanhydrin (II) in the presence of BuMgCl results in transcyanation reaction to afford the corresponding α‐cyanohydroxylamines (III) in good yields.
ChemInform Abstract: Development of a Fluorous, Oxime‐Based Palladacycle for Microwave‐Promoted Carbon—Carbon Coupling Reactions in Aqueous Media.
Authors: Susanto Woen , Chu Chi‐Yuan , Ang Wei Jie , Chou Tzyy‐Chao , Lo Lee‐Chiang , Lam Yulin
Published: May 2012

The thermally stable palladacycle promotes the Suzuki—Miyaura, Sonogashira, and Stille coupling reactions under microwave irradiation at high temperatures, thus significantly shortening the reaction time.
ChemInform Abstract: Sulfamic Acid Functionalized Magnetic Nanoparticles: An Efficient Solid Acid for the Multicomponent Condensations
Authors: Yarahmadi Hossein , Shaterian Hamid Reza
Published: May 2012

of 2‐naphthol with aromatic aldehydes and amides or carbamates (17 examples)
ChemInform Abstract: Triflic Acid‐Functionalized Silica‐Coated Magnetic Nanoparticles as a Magnetically Separable Catalyst for Synthesis of gem‐Dihydroperoxides.
Authors: Liu Yong‐Hui , Deng Jia , Gao Jian‐Wu , Zhang Zhan‐Hui
Published: May 2012

The catalyst can be easily recycled and reused for seven times without significant loss of activity.
ChemInform Abstract: Highly Efficient and Enantioselective α‐Arylation of Cycloalkanones by Scandium‐Catalyzed Diazoalkane—Carbonyl Homologation.
Authors: Rendina Victor L. , Kaplan Hilan Z. , Kingsbury Jason S.
Published: May 2012

The racemic version of the process proceeds with good to excellent yields.
ChemInform Abstract: Enantioselective Organocatalytic Three‐Component Petasis Reaction Among Salicylaldehydes, Amines, and Organoboronic Acids.
Authors: Han Wen‐Yong , Wu Zhi‐Jun , Zhang Xiao‐Mei , Yuan Wei‐Cheng
Published: May 2012

In the presence of the newly designed thiourea‐binol catalyst, a broad range of alkylaminophenols is obtained in good yield and good to high enantioselectivity (up to 95% e.e.).
ChemInform Abstract: Direct Use of Esters in the Mukaiyama Aldol Reaction: A Powerful and Convenient Alternative to Aldehydes.
Authors: Inamoto Yoshihiro , Nishimoto Yoshihiro , Yasuda Makoto , Baba Akio
Published: May 2012

The method is compatible with many functional groups.
ChemInform Abstract: Synthesis of Novel 2,5‐Dihydrofuran Derivatives and Evalution of Their Anticancer Activity.
Authors: Zhang Yikai , Zhong Hanyu , Wang Tiantian , Geng Dongping , Zhang Mingfeng , Li Ke
Published: May 2012

Among the novel dihydrofuran derivatives, compound (VII) exhibits the highest activity against four human cancer cell lines.
ChemInform Abstract: Xanthan Sulfuric Acid as an Efficient, Green, Biodegradable, and Recyclable Solid Acid Catalyst for One‐Pot Synthesis of N‐Substituted Pyrroles under Solvent‐Free Conditions at Room Temperature.
Authors: Rahmatpour Ali
Published: May 2012

High yields of trisubstituted pyrroles (III) and (VI) are achieved in short reaction times (4—90 min) using the biopolymer‐based sulfuric acid as catalyst.
ChemInform Abstract: Development of a Copper(II)‐Catalyzed Three‐Component Tandem Synthesis of Isoindolinone Derivatives.
Authors: Sun Leon Xuetong , Zeng Tieqiang , Jiang Dong , Dai Li‐Yi , Li Chao‐Jun
Published: May 2012

An efficient and simple one‐pot synthesis of the title compounds is developed from inexpensive starting materials.
ChemInform Abstract: A Multi‐Component Domino Reaction for the Direct Access to Polyfunctionalized Indoles via Intermolecular Allylic Esterification and Indolation.
Authors: Jiang Bo , Yi Mian‐Shuai , Shi Feng , Tu Shu‐Jiang , Pindi Suresh , McDowell Patrick , Li Guigen
Published: May 2012

A chemo‐ and regioselective synthesis of the title compounds (IV) and (VII) is presented from very common and easily accessible inexpensive starting materials.
ChemInform Abstract: Synthesis and Evaluation of Hexahydropyrrolo[3,4‐d]isoxazole‐4,6‐diones and anti‐Stress Agents.
Authors: Badru Rahul , Anand Preet , Singh Baldev
Published: May 2012

Compound (IIIa) exhibits significant anti‐stress activity in immobilization induced acute stress in mice.
ChemInform Abstract: Synthesis and Antimicrobial Activity of Pyrrolyl/Pyrazolyl Arylaminosulfonylmethyl 1,3,4‐Oxadiazoles, 1,3,4‐Thiadiazoles and 1,2,4‐Triazoles.
Authors: Padmaja Adivireddy , Muralikrishna Akkarapalli , Rajasekhar Chittoor , Padmavathi Venkatapuram
Published: May 2012

Title compounds such as (VI), (VIII), (IX), (X), (XII) and (XIII) are synthesized starting with cyclocondensation of hydrazide (I) and carboxylic acid (II).
ChemInform Abstract: ZnO Nanoparticles: Efficient and Versatile Reagents for Synthesis of 1,4‐Disubstituted 1,2,3‐Triazoles
Authors: Sadeghi Bahareh , Hassanabadi Alireza , Kamali Mohammad
Published: May 2012

21 examples
ChemInform Abstract: Simultaneous Synthesis of Both Rings of Chromenes via a Benzannulation/o‐Quinone Methide Formation/Electrocyclization Cascade.
Authors: Majumdar Nilanjana , Korthals Keith A. , Wulff William D.
Published: May 2012

The reaction of an α,β‐unsaturated Fischer carbene complex of chromium with a propargyl ether bearing an alkenyl group on the propargylic carbon affords the desired chromenes, including chromene (IIIg), which is transformed to vitamin E (IV).
ChemInform Abstract: Synthesis and Biological Evaluation of New Thiosubstituted Oxadiazole Derivatives of Coumarin under Solvent‐Free Conditions.
Authors: Bobade Vivek D. , Patil Sachin V. , Gaikwad Nitin D.
Published: May 2012

Compounds (III), (Va) and (Vd) exhibit good antifungal as well as antibacterial activities.
ChemInform Abstract: Montmorillonite K‐10 Mediated Green Synthesis of Cyano Pyridines: Their Evaluation as Potential Inhibitors of PDE4.
Authors: Reddy T. Ram , Reddy G. Rajeshwar , Reddy L. Srinivasula , Jammula Subbarao , Lingappa Y. , Kapavarapu Ravikumar , Meda Chandana Lakshmi T. , Parsa Kishore V. L. , Pal Manojit
Published: May 2012

Functionalized cyanopyridines (V) (18 examples) are efficiently obtained in a chemo‐ and regioselective four‐component reaction of β‐keto ester, arylaldehyde, malononitrile, and an alcohol using montmorillonite K10 as efficient and reusable catalyst.
ChemInform Abstract: Preparation of a Series of Novel Bichalcones Linked with a 1,4‐Dimethylenepiperazine Moiety and Examination of Their Cytotoxicity.
Authors: Reddy Mopuru Vijaya Bhaskar , Chen Shih‐Shun , Lin Meng‐Liang , Chan Hsiu‐Hui , Kuo Ping‐Chung , Wu Tian‐Shung
Published: May 2012

Among the new bichalcones synthesized (15 examples), derivatives (Ia) and (Id) display significant cytotoxicity against 25 human tumor cell lines.
ChemInform Abstract: A Facile Synthesis of 6‐Substituted 7‐Arylthieno[2,3‐b]pyrazines from 2‐Chloropyrazine.
Authors: Kobayashi Kazuhiro , Suzuki Teruhiko
Published: May 2012

A three‐step one‐pot procedure is elaborated for the conversion of ketones (III) and (VIII) into corresponding thienopyrazines (V) and (IX).
ChemInform Abstract: Synthesis and Biological Activity of Dihydroimidazole and 3,4‐Dihydrobenzo[4,5]imidazo[1,2‐a][1,3,5]triazines.
Authors: Soliman Ahmed M. , Mohamed Shaaban K. , El Remaily Mahmoud A. A. , Abdel‐Ghany H.
Published: May 2012

A variety of new dihydroimidazole and benzoimidazotriazine derivatives is synthesized by acid‐catalyzed reaction of 2‐guanidinobenzimidazole (I) with active halogenated methylene compounds or ketones, respectively.
ChemInform Abstract: Discovery of Artemisinin‐Glycolipid Hybrids as anti‐Oral Cancer Agents.
Authors: Ricci Jeremy , Kim Minkyu , Chung Won‐Yoon , Park Kwang‐Kyun , Jung Mankil
Published: May 2012

Title compounds such as (I) and (II) show exceptional anticancer activity, particularly against oral carcinoma cancer cell lines.
ChemInform Abstract: The First Total Synthesis of Gravicycle.
Authors: Ueda Katsuaki , Sato Itaru , Hirama Masahiro
Published: May 2012

An efficient assembly of highly functionalized biaryl ethers (III) via Cu‐catalyzed O‐arylation of suitably protected pyrogallol derivatives (I) using triarylbismuth (V) diacetate is developed and applied to the total synthesis of gravicycle (VI).
ChemInform Abstract: Light‐Harvesting Hybrid Assemblies
Authors: Rao K. Venkata , Datta K. K. R. , Eswaramoorthy Muthusamy , George Subi J.
Published: May 2012

Review: 69 refs.
ChemInform Abstract: New Directions in Ketene Chemistry: The Land of Opportunity
Authors: Allen Annette D. , Tidwell Thomas T.
Published: May 2012

Review: 85 refs.
ChemInform Abstract: Olefin Cross‐Metathesis for the Synthesis of Heteroaromatic Compounds.
Authors: Donohoe Timothy J. , Bower John F. , Chan Louis K. M.
Published: May 2012

Review: 52 refs.
ChemInform Abstract: Peptide and Glycopeptide Dendrimer Apple Trees as Enzyme Models and for Biomedical Applications.
Authors: Reymond Jean‐Louis , Darbre Tamis
Published: May 2012

Review: 84 refs.
ChemInform Abstract: Transition‐Metal‐Catalyzed Functionalization of Propargylic Alcohols and Their Derivatives
Authors: Bauer Eike B.
Published: May 2012

Review: ca. 150 refs.
ChemInform Abstract: Functionalized Cyclodextrins as First and Second Coordination Sphere Ligands for Aqueous Organometallic Catalysis
Authors: Hapiot Frederic , Bricout Herve , Tilloy Sebastien , Monflier Eric
Published: May 2012

Review: 46 refs.
ChemInform Abstract: Transfer Hydrogenation with Hantzsch Esters and Related Organic Hydride Donors
Authors: Zheng Chao , You Shu‐Li
Published: May 2012

Review: ca. 150 refs.
ChemInform Abstract: Sulfated Polysaccharides as Specific Biologically Active Materials
Authors: Muschin Tegshi , Han Shuqin , Ishimura Hisataka , Yoshida Takashi
Published: May 2012

Review: 43 refs.
ChemInform Abstract: Oligosaccharide—Cyclodextrin Conjugates: Synthesis and Biological Affinity Towards Lectins
Authors: Smiljanic Nicolas , Yockot Duplex , Cendret Virginie , Francois‐Heude Marc , Moreau Vincent , Djedaini‐Pilard Florence
Published: May 2012

Review: 98 refs.
ChemInform Abstract: The Crucial Role of H‐Bonding in the Mechanisms of Reactions with Diamines in Aprotic Solvents
Authors: Alvaro Cecilia E. Silvana , Nudelman Norma Sbarbati
Published: May 2012

Review: 51 refs.
ChemInform Abstract: Controlling Chirality with Helix Inversion in Cholesteric Liquid Crystals
Authors: Katsonis Nathalie , Lacaze Emmanuelle , Ferrarini Alberta
Published: May 2012

Review: 109 refs.
CD147 immunohistochemistry discriminates between reactive mesothelial cells and malignant mesothelioma
Authors: Pinheiro Céline , Longatto‐Filho Adhemar , Soares Tony R. , Pereira Helena , Bedrossian Carlos , Michael Claire , Schmitt Fernando C. , Baltazar Fátima
Published: May 2012

Malignant mesothelioma (MM) is a rare form of cancer. Its histopathological diagnosis is very difficult, as it exhibits a number of different appearances that can be misinterpreted as metastatic invasion or atypical hyperplasia. Thus, there is an urgent need to identify adequate markers to distinguish between benign and malignant cells, allowing the implementation of appropriate therapies and, possibly, specific directed therapies. MM, like other tumors, show an increase in glucose uptake, due to high rates of glycolysis, inducing an intracellular overload of acids. In this context, monocarboxylate transporters (MCTs) emerge as important players, by mediating the transmembranar co‐transport of lactate with a proton, thereby, regulating pH and allowing continuous glycolysis. Importantly, proper MCT expression and activity depend on its co‐expression with a chaperone, CD147, which is associated with poor prognosis in cancer. Twenty‐two samples including reactive mesothelial cells, MM, and atypical mesothelial hyperplasias were evaluated for immunoexpression of MCT1, MCT4, and CD147. Expression of these proteins was compared with GLUT1 as a new promising marker for MM. Although MCT isoforms were not differentially expressed in the two types of cytological specimens, CD147, as GLUT1, was almost exclusively expressed in MM. Both MCT1 and MCT4 are not able to discriminate between mesothelial reactive cells and mesothelial malignant cells, while CD147 was able to distinguish these two proliferations. If confirmed, besides being a good marker for identification of MM, CD147 may also be a target for therapeutical strategies in this rare type of tumor. Diagn. Cytopathol. 2012;40:478–483. © 2012 Wiley Periodicals, Inc.
In Situ Photoactivated AgCl/Ag Nanocomposites with Enhanced Visible Light Photocatalytic and Antibacterial Activity
Authors: Dong Lihong , Liang Dadong , Gong Ruchun
Published: May 2012

AgCl nanoparticles with a diameter of 50–100 nm were synthesized in ethylene glycol with the assistance of poly(vinylpyrrolidone) at room temperature. A photoactivation process was then introduced by exposing the as‐obtained AgClnanoparticle solution to common fluorescent lamp or direct sunlight irradiation to form a uniform layer of Ag nanoparticles (5–10 nm) on the surface of the AgCl nanoparticles. The AgCl/Ag nanocomposites showed higher visible light photocatalytic activity for decomposing organic pollutants [such as methyl orange (MO), methyl blue (MB), and rhodamine B (RhB)] under the irradiation of common fluorescent lamp or direct sunlight. Recycle photocatalysis experiments indicated that the AgCl/Ag nanocomposite exhibited higher stability. Moreover, the AgCl/Ag nanocomposites showed better antibacterial properties on Escherichia coli, Staphylococcus aureus, and Bacillus subtilis.
EfficientN‐Alkyl Enamination of 3‐(Thiobenzoyl)pyrrolo[2,3‐b]quinoxalin‐2‐one,E/ZIsomerisation of the Reaction Products and Potential Fluorescent Sensors for ­Zinc(II) Ion
Authors: Ostrowska Katarzyna , Piegza Edyta , Rąpała‐Kozik Maria , Stadnicka Katarzyna
Published: May 2012

An efficient and rapid procedure for theN‐alkyl enamination from thioketones to push–pull (E/Z)‐enamine derivatives is reported. The starting thioketone2was obtained by regioselective thionation of 3‐benzoylpyrrolo[2,3‐b]quinoxalin‐2‐one (1) with Lawesson's reagent (LR).1H NMR and X‐ray crystal structure analyses of 1‐aryl‐3‐(alkylaminophenylmethylidene)pyrrolo[2,3‐b]quinoxalin‐2‐ones3–6confirmed that theEdiastereoisomers predominated. Interconversion of the isolatedEform of3band4ainto theZconfiguration and theirE/Zequilibria in [D6]DMSO were studied by temperature‐dependent1H NMR spectroscopy. The photophysical properties of compounds1–6are also reported. We found that the non‐fluorescent compounds3a–6aare chemosensors for the zinc ion. Fluorescent titrations of these sensors with zinc(II) acetate showed that compound6ahas the best working range of zinc concentrations withKd= 3.77 00 ± 0.51 μM.
On the quantification of intertest variability in ecotoxicity data with application to species sensitivity distributions
Authors: Hickey Graeme L. , Craig Peter S. , Luttik Robert , de Zwart Dick
Published: May 2012

Ecotoxicological hazard assessment relies on species effect data to estimate quantities such as the predicted no-effect concentration. While there is a concerted effort to quantify uncertainty in risk assessments, the uncertainty due to intertest variability in species effect measurements is an overlooked component. The European Union Registration, Evaluation, Authorisation, and Restriction of Chemicals (REACH) guidance document suggests that multiple toxicity records for a given chemical–species combination should be aggregated by the geometric mean. Ignoring this issue or applying unjustified so-called harmonization methods weakens the defensibility of uncertainty quantification and interpretation about properties of ecological models, for example, the predicted no-effect concentration. In the present study, the authors propose a simple and broadly theoretically justifiable model to quantify intertest variability and analyze it using Bayesian methods. The value of data in ecotoxicity databases is maximized by using (interval-)censored data. An exploratory analysis is provided to support the model. The authors conclude, based on a large ecotoxicity database of acute effects to aquatic species, that the standard deviation of intertest variability is approximately a factor (or fold-difference) of 3. The consequences for decision makers of (not) adjusting for intertest variability are demonstrated. Environ. Toxicol. Chem. 2012; 31: 1903–1910. © 2012 SETAC
Does insecticide drift adversely affect grasshoppers (Orthoptera: Saltatoria) in field margins? A case study combining laboratory acute toxicity testing with field monitoring data
Authors: Bundschuh Rebecca , Schmitz Juliane , Bundschuh Mirco , Brühl Carsten Albrecht
Published: May 2012

The current terrestrial risk assessment of insecticides regarding nontarget arthropods considers exclusively beneficial organisms, whereas herbivorous insects, such as grasshoppers, are ignored. However, grasshoppers living in field margins or meadows adjacent to crops may potentially be exposed to insecticides due to contact with or ingestion of contaminated food. Therefore, the present study assessed effects of five active ingredients of insecticides (dimethoate, pirimicarb, imidacloprid, lambda-cyhalothrin, and deltamethrin) on the survival of Chorthippus sp. grasshopper nymphs by considering two routes of exposure (contact and oral). The experiments were accompanied by monitoring field margins that neighbored cereals, vineyards, and orchards. Grasslands were used as reference sites. The laboratory toxicity tests revealed a sensitivity of grasshoppers with regard to the insecticides tested in the present study similar to that of the standard test species used in arthropod risk assessments. In the field monitoring program, increasing grasshopper densities were detected with increasing field margin width next to cereals and vineyards, but densities remained low over the whole range of field margins from 0.5 to 20 m next to orchards. Grasshopper densities equivalent to those of grassland sites were only observed in field margins exceeding 9 m in width, except for field margins next to orchards. These results may indicate that current insecticide risk assessments are insufficiently protective for grasshoppers in field margins. Environ. Toxicol. Chem. 2012; 31: 1874–1879. © 2012 SETAC
A Bayesian belief network (BBN) for combining evidence from multiple CO2 leak detection technologies
Authors: Yang Ya‐Mei , Small Mitchell J. , Ogretim Egemen O. , Gray Donald D. , Wells Arthur W. , Bromhal Grant S. , Strazisar Brian R.
Published: May 2012

A Bayesian belief network (BBN) methodology is developed for integrating CO2 leak detection inferences from multiple monitoring technologies at a geologic sequestration site. The methodology is demonstrated using two monitoring methods: near‐surface soil CO2 flux measurement and near‐surface perfluoromethylcyclohexane (PMCH) tracer monitoring, from the Zero Emission Research and Technology (ZERT) release test in 2007. Statistical models are fitted to natural background soil CO2 flux and background PMCH tracer concentrations to determine critical levels for leak inference. Leakage‐induced increments of soil CO2 flux and PMCH tracer concentrations are computed through TOUGH2 simulations for different leakage rates and subsurface permeabilities. The background characterizations and the simulation results are subsequently used to determine the conditional probabilities of leak detection in the BBN model. The BBN model is illustrated for use in evaluating the performance of alternative monitoring networks in a network design phase, and for combining inferences from multiple observations in the operational phase of a site. The detection capabilities of combined networks with different monitoring densities for soil CO2 flux and PMCH tracer concentration are compared. Given the test condition, the greater sensitivity of the PMCH tracer allows it to detect smaller leaks, while detection by the soil CO2 flux monitors implies that a larger leak is most likely present. © 2012 Society of Chemical Industry and John Wiley & Sons, Ltd
Refinement of stopping rules during treatment of hepatitis C genotype 1 infection with boceprevir and peginterferon/ribavirin
Authors: Jacobson Ira M. , Marcellin Patrick , Zeuzem Stefan , Sulkowski Mark S. , Esteban Rafael , Poordad Fred , Bruno Savino , Burroughs Margaret H. , Pedicone Lisa D. , Boparai Navdeep , Deng Weiping , DiNubile Mark J. , Gottesdiener Keith M. , Brass Clifford A. , Albrecht Janice K. , Bronowicki Jean-Pierre
Published: May 2012

In comparison with peginterferon/ribavirin alone, boceprevir with peginterferon/ribavirin significantly improves sustained virological response (SVR) rates in patients with chronic hepatitis C virus (HCV) genotype 1 infections, but treatment failure remains a significant problem. Using phase 3 trial databases, we sought to develop stopping rules for patients destined to fail boceprevir-based combination therapy in order to minimize drug toxicity, resistance, and costs in the face of ultimate futility. Exploratory post hoc analyses using data from the Serine Protease Inhibitor Therapy 2 (SPRINT-2) study (treatment-naive patients) and the Retreatment With HCV Serine Protease Inhibitor Boceprevir and Pegintron/Rebetol 2 (RESPOND-2) study (treatment-experienced patients) were undertaken to determine whether protocol-specified stopping rules (detectable HCV RNA at week 24 for SPRINT-2 and at week 12 for RESPOND-2) could be refined and harmonized. In SPRINT-2, a week 12 rule with an HCV RNA cutoff of ≥100 IU/mL would have discontinued therapy in 65 of 195 failures (sensitivity = 33%) without sacrificing a single SVR among 475 successes (specificity = 100%). Viral variants emerged after week 12 in 36 of the 49 evaluable patients (73%) who would have discontinued at week 12 using a ≥100 IU/mL stopping rule. In RESPOND-2, five of six patients with week 12 HCV RNA levels between the lower limit of detection (9.3 IU/mL) and the lower limit of quantification (25 IU/mL) who continued therapy despite the protocol-stipulated futility rule achieved SVR; one additional patient with a week 12 HCV RNA level of 148 IU/mL also continued therapy, had undetectable HCV RNA at week 16, and attained SVR.

Conclusion:

Although a stopping rule of detectable HCV RNA at week 12 would have forfeited some SVR cases, week 12 HCV RNA levels ≥100 IU/mL almost universally predicted a failure to achieve SVR in both treatment-naive and treatment-experienced patients. In boceprevir recipients, the combination of 2 stopping rules—an HCV RNA level ≥100 IU/mL at week 12 and detectable HCV RNA at week 24—maximized the early discontinuation of futile therapy and minimized premature treatment discontinuation. (HEPATOLOGY 2012)
Risk of hip fracture associated with hepatitis c virus infection and hepatitis C/human immunodeficiency virus coinfection
Authors: Lo Re Vincent , Volk Jessica , Newcomb Craig W. , Yang Yu-Xiao , Freeman Cristin P. , Hennessy Sean , Kostman Jay R. , Tebas Pablo , Leonard Mary B. , Localio Russell A.
Published: May 2012

Hepatitis C virus (HCV) infection has been associated with reduced bone mineral density, but its association with fracture rates is unknown, particularly in the setting of human immunodeficiency virus (HIV) coinfection. Our aims were to determine whether persons with HCV infection alone are at increased risk for hip fracture, compared to uninfected individuals, and to examine whether the risk of hip fracture is higher among HCV/HIV-coinfected persons, compared to those with HCV alone, those with HIV alone, and those uninfected with either virus. We conducted a cohort study in 36,950 HCV/HIV-coinfected, 276,901 HCV-monoinfected, 95,827 HIV-monoinfected, and 3,110,904 HCV/HIV-uninfected persons within the U.S. Medicaid populations of California, Florida, New York, Ohio, and Pennsylvania (1999-2005). Incidence rates of hip fracture were lowest among uninfected persons (1.29 events/1,000 person-years), increased with the presence of either HIV infection (1.95 events/1,000 person-years) or HCV infection (2.69 events/1,000 person-years), and were highest among HCV/HIV-coinfected individuals (3.06 events/1,000 person-years). HCV/HIV coinfection was associated with an increased relative hazard (adjusted hazard ratio [HR] [95% confidence interval; CI]) of hip fracture, compared to HCV-monoinfected (HR, 1.38; 95% CI: 1.25-1.53), HIV-monoinfected (females: HR, 1.76; 95% CI: 1.44-2.16; males: HR, 1.36; 95% CI: 1.20-1.55), and HCV/HIV-uninfected persons (females: HR, 2.65; 95% CI: 2.21-3.17; males: HR, 2.20; 95% CI: 1.97-2.47). HCV monoinfection was associated with an increased risk of hip fracture, compared to uninfected individuals, and the relative increase was highest in the youngest age groups (females, 18-39 years: HR, 3.56; 95% CI: 2.93-4.32; males, 18-39 years: HR, 2.40; 95% CI: 2.02-2.84).

Conclusion:

Among Medicaid enrollees, HCV/HIV coinfection was associated with increased rates of hip fracture, compared to HCV-monoinfected, HIV-monoinfected, and HCV/HIV-uninfected persons. HCV-monoinfected patients had an increased risk of hip fracture, compared to uninfected individuals.