bluuebunny/crossref_metadata_2025 huggingface dataset:
ZrO2/InAlN/GaN Metal–Oxide–Semiconductor Heterostructure Field-Effect Transistors with InAlN Barrier of Different Compositions
Authors: Gregušová Dagmar , Hušeková Kristína , Stoklas Roman , Blaho Michal , Jurkovič Michal , Carlin Jean-Francois , Grandjean Nicolas , Kordoš Peter
Published: May 2013

We report on InAlN/GaN heterostructure metal–oxide–semiconductor field-effect transistors (MOSHFETs) with an InAlN barrier layer of different compositions (xInN= 13, 17, and 21%) and ZrO2gate-insulator/passivation. Static measurements yielded higher drain currents than those on unpassivated HFET counterparts and the currents increased with decreasedxInN. Post deposition annealing of the ZrO2insulator had less influence on the static performance but remarkable changes were observed on the capacitance–voltage characteristics. The capacitance hysteresis in both channel depletion and barrier accumulation regions was significantly suppressed after annealing. This indicates a reduction of the interfacial trap states and of fixed charge in the oxide. Pulsed current–voltage measurements confirmed this conclusion – the gate lag of only ∼80% was evaluated for 200 ns pulse width, independently on the composition of the InAlN barrier layer. These results support an application of high permittivity ZrO2gate-insulator/passivation for the preparation of high-performance InAlN/GaN MOSHFETs.
Surface States Influence on Capacitance Properties of Dielectric/AlGaN/GaN Heterostructures
Authors: Osvald Jozef
Published: May 2013

We have studied capacitance voltage characteristics of metal/insulator/AlGaN/GaN structures and the influence of surface traps on them. The behavior and a shape of the capacitance–voltage curves have been analyzed. We have obtained two steps in the characteristics. One step is the transition from the insulator capacitance to the capacitance plateau formed by the insulator capacitance and the capacitance of AlGaN layer in series and the second one corresponds to the depletion of GaN buffer layer. Interface traps present in the structure shift the capacitance–voltage (C–V) curves and for higher density of traps they also change the slope of the capacitance curves at the steps. In accumulation, acceptor type interface traps change their charge state and stretch theC–Vcurves while donor type interface traps stretch theC–Vcurves in depletion.
A New Method to Modify Two-Dimensional Electron Gas Density by GaN Cap Etching
Authors: Li Zhongda , Chow T. Paul
Published: May 2013

We have experimentally demonstrated a new method for modifying the two-dimensional electron density (2DEG) at the AlGaN/GaN interface by etching of the GaN cap layer on top of the AlGaN. GaN MOS capacitors have been fabricated on samples with partially or fully etched GaN cap, and the 2DEG density has been extracted. The results show a linear relation between the 2DEG density and the thickness of the GaN cap being etched. We have also fabricated van der Pauw structures and obtained the 2DEG density using Hall measurements, and the results are consistent with that from the GaN MOS capacitors.
Reduction in Buffer Leakage Current with Mn-Doped GaN Buffer Layer Grown by Metal Organic Chemical Vapor Deposition
Authors: Yamamoto Taiki , Sazawa Hiroyuki , Nishikawa Naohiro , Kiuchi Maki , Ide Toshihide , Shimizu Mitsuaki , Inoue Takayuki , Hata Masahiko
Published: May 2013

The effect of Mn-doping into a GaN buffer layer grown by metal organic chemical vapor deposition (MOCVD) on the reduction in the leakage current of high-electron-mobility transistors (HEMTs) was investigated. Both the surface morphology and crystallinity maintained their quality even after heavy Mn-doping. The sheet resistance of GaN films increased with increasing amount of Mn-doping. The origin of semi-insulating GaN layer is considered to be electron scattering and the carrier compensation mechanism involving deep levels generated by the Mn impurity. When using the Mn-doped GaN buffer layer for the HEMT structure, the leakage current was reduced to five orders of magnitude lower than that without Mn-doping. Although Mn-doping is an effective technique for reducing the buffer leakage current, it is found that current collapse is emphasized when using the Mn-doped GaN buffer layer. We suggest that Mn atoms, which diffused to the GaN channel layer, induce the current collapse.
Circadian abnormalities in mouse models of smith–magenis syndrome: Evidence for involvement of RAI1
Authors: Lacaria Melanie , Gu Wenli , Lupski James R
Published: May 2013

Smith–Magenis syndrome (SMS; OMIM 182290) is a genomic disorder characterized by multiple congenital anomalies, intellectual disability, behavioral abnormalities, and disordered sleep resulting from an ∼3.7 Mb deletion copy number variant (CNV) on chromosome 17p11.2 or from point mutations in the gene RAI1. The reciprocal duplication of this region results in another genomic disorder, Potocki–Lupski syndrome (PTLS; OMIM 610883), characterized by autism, intellectual disability, and congenital anomalies. We previously used chromosome‐engineering and gene targeting to generate mouse models for PTLS (Dp(11)17/+), and SMS due to either deletion CNV or gene knock‐out (Df(11)17‐2/+ and Rai1+/−, respectively) and we observed phenotypes in these mouse models consistent with their associated human syndromes. To investigate the contribution of individual genes to the circadian phenotypes observed in SMS, we now report the analysis of free‐running period lengths in Rai1+/− and Df(11)17‐2/+ mice, as well as in mice deficient for another known circadian gene mapping within the commonly deleted/duplicated region, Dexras1, and we compare these results to those previously observed in Dp(11)17/+ mice. Reduced free‐running period lengths were seen in Df(11)17‐2/+, Rai1+/−, and Dexras1−/−, but not Dexras1+/− mice, suggesting that Rai1 may be the primary gene underlying the circadian defects in SMS. However, we cannot rule out the possibility that cis effects between multiple haploinsufficient genes in the SMS critical interval (e.g., RAI1 and DEXRAS1) either exacerbate the circadian phenotypes observed in SMS patients with deletions or increase their penetrance in certain environments. This study also confirms a previous report of abnormal circadian function in Dexras1−/− mice. © 2013 Wiley Periodicals, Inc.
Niche production strategies and shell matrix site variability at Albatross Bay, Cape York Peninsula
Authors: Morrison Michael
Published: May 2013

Albatross Bay, near Weipa on western Cape York Peninsula, is well known for the large number of anthropogenic late Holocene shell mound sites that occur in the region. Recent research on shell mound formation and use both here and elsewhere across northern Australia has focused upon the extent to which mound formation may have been tied to intensive use of periodically available gluts of the intertidal bivalve Anadara granosa. This paper explores whether such a model applies in the Albatross Bay region, drawing on data available from 477 shell matrix sites recorded in this region. Data on site size, morphology, composition, substrate type, proximity to contemporary shorelines and shell mound chronology support a model of Aboriginal people episodically and strategically targeting a highly variable niche estuarine resource base rather than intensively focusing on one species. It is proposed that these production strategies were characterised by a high degree of flexibility in terms of resource focus, at times involving a considerable emphasis on A. granosa, but also incorporating other estuarine resources, and that the level or intensity of production was able to be scaled up or down in line with resource availability and abundance. This production system was based upon nuanced knowledge of annual and intra‐annual ecosystem dynamics along with social organisation and communication networks that facilitated a high degree of flexibility around the strategic exploitation of variable estuarine resource bases.
On the use of biplot analysis for multivariate bibliometric and scientific indicators
Authors: Torres‐Salinas Daniel , Robinson‐García Nicolás , Jiménez‐Contreras Evaristo , Herrera Francisco , López‐Cózar Emilio Delgado
Published: May 2013

Bibliometric mapping and visualization techniques represent one of the main pillars in the field of scientometrics. Traditionally, the main methodologies employed for representing data are multidimensional scaling, principal component analysis, or correspondence analysis. In this paper we aim to present a visualization methodology known as biplot analysis for representing bibliometric and science and technology indicators. A biplot is a graphical representation of multivariate data, where the elements of a data matrix are represented according to dots and vectors associated with the rows and columns of the matrix. In this paper, we explore the possibilities of applying biplot analysis in the research policy area. More specifically, we first describe and introduce the reader to this methodology and secondly, we analyze its strengths and weaknesses through 3 different case studies: countries, universities, and scientific fields. For this, we use a biplot analysis known asJK‐biplot. Finally, we compare the biplot representation with other multivariate analysis techniques. We conclude that biplot analysis could be a useful technique in scientometrics when studying multivariate data, as well as an easy‐to‐read tool for research decision makers.
Rational Heme Protein Design: All Roads Lead to Rome
Authors: Lin Ying‐Wu , Sawyer Elizabeth B. , Wang Jiangyun
Published: May 2013

Heme proteins are among the most abundant and important metalloproteins, exerting diverse biological functions including oxygen transport, small molecule sensing, selective CH bond activation, nitrite reduction, and electron transfer. Rational heme protein designs focus on the modification of the heme‐binding active site and the heme group, protein hybridization and domain swapping, and de novo design. These strategies not only provide us with unique advantages for illustrating the structure–property–reactivity–function (SPRF) relationship of heme proteins in nature but also endow us with the ability to create novel biocatalysts and biosensors.
Phenotypes from ancient DNA: Approaches, insights and prospects
Authors: Fortes Gloria G. , Speller Camilla F. , Hofreiter Michael , King Turi E.
Published: May 2013

The great majority of phenotypic characteristics are complex traits, complicating the identification of the genes underlying their expression. However, both methodological and theoretical progress in genome‐wide association studies have resulted in a much better understanding of the underlying genetics of many phenotypic traits, including externally visible characteristics (EVCs) such as eye and hair color. Consequently, it has become possible to predict EVCs from human samples lacking phenotypic information. Predicting EVCs from genetic evidence is clearly appealing for forensic applications involving the personal identification of human remains. Now, a recent paper has reported the genetic determination of eye and hair color in samples up to 800 years old. The ability to predict EVCs from ancient human remains opens up promising perspectives for ancient DNA research, as this could allow studies to directly address archaeological and evolutionary questions related to the temporal and geographical origins of the genetic variants underlying phenotypes.
Antioxidant activity, lipophilicity and extractability of polyphenols from pig skin – development of analytical methods for skin permeation studies
Authors: Zillich Olesya V. , Schweiggert‐Weisz Ute , Hasenkopf Katrin , Eisner Peter , Kerscher Martina
Published: May 2013

Permeation of polyphenols through the stratum corneum barrier is a precondition for the protective action of polyphenols against oxidative skin damage. Prior to in vitro skin permeation experiments, we developed a method for the quantification of polyphenols in pig skin, including organic solvent extraction and HPLC analysis. Catechine hydrate, epigallocatechin gallate, trans‐resveratrol, quercetin, rutin and protocatechuic acid were chosen for this study as representatives of phenolics with different lipophilicity and molecular weight. The antioxidative activities of polyphenols as well as their octanol–water partition coefficients at different pH values were determined. Extraction of polyphenols from pig skin was optimized by variation of solvent composition, homogenization intensity and time, as well as partial exclusion of oxygen during extraction. The highest recovery rates could be reached by extraction with the methanol–water mixture (90:10, v/v), containing 0.2 g/L l‐ascorbic acid, after the cryo‐milling for 4 min. Recoveries of 72% for total phenolics, 96% for quercetin and protocatechuic acid, 90% for rutin and 74% for trans‐resveratrol, were achieved. These extraction parameters will be selected for the polyphenol extraction from pig skin for further in vitro drug permeation studies. Copyright © 2013 John Wiley & Sons, Ltd.
Concept and role of extreme objects in PCA/SIMCA
Authors: Pomerantsev Alexey L. , Rodionova Oxana Ye
Published: May 2013

For the construction of a reliable decision area in the soft independent modeling by class analogy (SIMCA) method, it is necessary to analyze calibration data revealing the objects of special types such as extremes and outliers. For this purpose, a thorough statistical analysis of the scores and orthogonal distances is necessary. The distance values should be considered as any data acquired in the experiment, and their distributions are estimated by a data‐driven method, such as a method of moments or similar. The scaled chi‐squared distribution seems to be the first candidate among the others in such an assessment. This provides the possibility of constructing a two‐level decision area, with the extreme and outlier thresholds, both in case of regular data set and in the presence of outliers. We suggest the application of classical principal component analysis (PCA) with further use of enhanced robust estimators both for the scaling factor and for the number of degrees of freedom. A special diagnostic tool called extreme plot is proposed for the analyses of calibration objects. Extreme objects play an important role in data analysis. These objects are a mandatory attribute of any data set. The advocated dual data‐driven PCA/SIMCA (DD‐SIMCA) approach has demonstrated a proper performance in the analysis of simulated and real‐world data for both regular and contaminated cases. DD‐SIMCA has also been compared with robust principal component analysis, which is a fully robust method. Copyright © 2013 John Wiley & Sons, Ltd.
ChemInform Abstract: Structural Characterization of the Perovskite Series Sr1‐xLaxTi0.5Mn0.5O3.
Authors: Qasim Ilyas , Kennedy Brendan J.
Published: May 2013

The perovskites Sr1‐xLaxTi0.5Mn0.5 O3, x = 0, 0.1, 0.2, 0.3, 0.4 and 0.5 are synthesized by solid state reaction of La2O3, SrCO3, TiO2, and MnCO3 (1350—1450 °C, 2 d).
ChemInform Abstract: Crystal Structure and Properties of High‐Pressure‐Synthesized BiRhO3, LuRhO3, and NdRhO3.
Authors: Yi Wei , Liang Qifeng , Matsushita Yoshitaka , Tanaka Masahiko , Hu Xiao , Belik Alexei A.
Published: May 2013

BiRhO3 (I), LuRhO3 (II), and NdRhO3 (III) are prepared by solid state reaction of stoichiometric mixtures of M2O3 (M: Bi, Lu, Nd) and Rh2O3 (Au capsules, 6 GPa, 1600 °C for (I), 1300 °C for (II) and (III), 2 h).
ChemInform Abstract: Structure and Optical Properties of Cubic Gallium Oxynitride Synthesized by Solvothermal Route.
Authors: Oberlaender Andreas , Kinski Isabel , Zhu Wenliang , Pezzotti Giuseppe , Michaelis Alexander
Published: May 2013

Cubic gallium oxynitride is synthesized by solvothermal processing of a gallium ethylene diamine complex and H2O (autoclave, 200 °C, 1 d).
ChemInform Abstract: New Bismuth Selenium Oxides: Syntheses, Structures, and Characterizations of Centrosymmetric Bi2(SeO3)2(SeO4) and Bi2(TeO3)2(SeO4) and Noncentrosymmetric Bi(SeO3)(HSeO3).
Authors: Lee Eun Pyo , Song Seung Yoon , Lee Dong Woo , Ok Kang Min
Published: May 2013

The new title compounds are structurally characterized by single crystal XRD.
ChemInform Abstract: Asymmetric, Regioselective Bromohydroxylation of 2‐Aryl‐2‐propen‐1‐ols Catalyzed by Quinine‐Derived Catalysts.
Authors: Zhang Ye , Xing Hui , Xie Weiqing , Wan Xiaolong , Lai Yisheng , Ma Dawei
Published: May 2013

A first example of an enantioselective and regioselective bromohydroxylation of 2‐aryl‐2‐propen‐1‐ols is developed.
ChemInform Abstract: Synthesis of Planar Chiral [2.2]Paracyclophanyl Imidazo[1,5‐a]pyridinium Salts for the Rhodium‐Catalyzed Asymmetric Arylation.
Authors: Wang Dengxia , Ma Yudao , He Fuyan , Duan Wenzeng , Zhao Lei , Song Chun
Published: May 2013

A series of novel planar‐chiral NHC precursors are synthesized and applied in the Rh‐catalyzed asymmetric 1,2‐addition of arylboronic acids to aromatic aldehydes.
ChemInform Abstract: Selective Reduction of Carboxylic Acids to Aldehydes Catalyzed by B(C6F5)3.
Authors: Bezier David , Park Sehoon , Brookhart Maurice
Published: May 2013

A protocol for the selective reduction of carboxylic acids to aldehydes via intermediate disilyl acetals is presented.
ChemInform Abstract: Green and Scalable Aldehyde‐Catalyzed Transition Metal‐Free Dehydrative N‐Alkylation of Amides and Amines with Alcohols.
Authors: Xu Qing , Li Qiang , Zhu Xiaogang , Chen Jianhui
Published: May 2013

An efficient method for the N‐alkylation of various sulfonamides and amines with alcohols is developed (40 examples in all) using the corresponding aldehydes as the catalyst.
ChemInform Abstract: A Straightforward Route to Homoallyl‐Homocrotylamines Promoted by a Titanium Complex.
Authors: Toulot Stephanie , Bonnin Quentin , Comte Virginie , Adriaenssens Louis , Richard Philippe , Le Gendre Pierre
Published: May 2013

This publication also contains theoretical studies and calculations concerning the reaction.
ChemInform Abstract: An Efficient Transesterification of β‐Oxodithioesters Catalyzed by Stannous Chloride under Solvent‐Free Conditions.
Authors: Devi Nepram Sushuma , Singh Sarangthem Joychandra , Singh Okram Mukherjee
Published: May 2013

Notable features of the protocol include a short reaction time, mild conditions, and the use of an inexpensive catalyst.
ChemInform Abstract: Metalated N‐Heterocyclic Reagents Prepared by the Frustrated Lewis Pair TMPMgCl·BF3 and Their Addition to Aromatic Aldehydes and Activated Ketones.
Authors: Manolikakes Sophia M. , Jaric Milica , Karaghiosoff Konstantin , Knochel Paul
Published: May 2013

Treatment of pyridines, quinoline and methylthiopyrazine with the frustrated Lewis pair TMPMgCl·BF3 leads to organofluoroborates which react readily with a variety of aromatic aldehydes or activated ketones (II) to the corresponding carbinols (III) in the absence of a transition metal catalyst.
ChemInform Abstract: A General Approach to Terminal Allenols.
Authors: Kuang Jinqiang , Xie Xi , Ma Shengming
Published: May 2013

A variety of hydroxyalkyl‐substituted allenes is prepared under optimized conditions A) in the presence of paraformaldehyde.
ChemInform Abstract: An Eco‐Sustainable Green Approach for the Synthesis of Propargylamines Using LiOTf as a Reusable Catalyst under Solvent‐Free Condition.
Authors: Dindulkar Someshwar D. , Kwan Baek , Lim Kwon Taek , Jeong Yeon Tae
Published: May 2013

The electronic effects of the aldehyde substituents as well as the nature of the secondary amine are found to affect reaction rate and yield.
ChemInform Abstract: A Novel Route to Organonitrites by Pd‐Catalyzed Cross‐Coupling of Sodium Nitrite and Potassium Organotrifluoroborates.
Authors: Al‐Masum Mohammad , Saleh Nabil , Islam Tasfia
Published: May 2013

Microwave‐assisted Pd‐catalyzed coupling of sodium nitrite with styryltrifluoroborates produces the desired products in high yields.
ChemInform Abstract: Regio‐ and Stereospecific Synthesis of (E)‐α‐Iodoenamide Moieties from Ynamides Through Iodotrimethylsilane‐Mediated Hydroiodation.
Authors: Sato Akihiro H. , Ohashi Kazuhiro , Iwasawa Tetsuo
Published: May 2013

Uncatalyzed addition reaction of TmsI or TmsBr and subsequent careful hydrolysis offers a facile approach to the highly functionalized target units.
ChemInform Abstract: Enantioselective Synthesis of Planar Chiral Ferrocenes via Palladium‐Catalyzed Direct Coupling with Arylboronic Acids.
Authors: Gao De‐Wei , Shi Yan‐Chao , Gu Qing , Zhao Zheng‐Le , You Shu‐Li
Published: May 2013

Various arylated aminoethylferrocene derivatives (I) are prepared easily using the reaction with boronic acids.
ChemInform Abstract: Efficient Manganese/Copper Bimetallic Catalyst for N‐Arylation of Amides and Sulfonamides under Mild Conditions in Water.
Authors: Teo Yong‐Chua , Yong Fui‐Fong , Ithnin Idzham Khalid , Yio Siew‐Hui Trionna , Lin Zhiyin
Published: May 2013

A facile, convenient and mild method for the synthesis of various of N‐arylamides and N‐arylsulfonamides is developed.
ChemInform Abstract: Rhodium‐Catalyzed Synthesis of 2,3‐Diaryl‐1,4‐diketones via Oxidative Coupling of Benzyl Ketones Using α‐Thioketone Oxidizing Reagent.
Authors: Arisawa Mieko , Li Guangzhe , Yamaguchi Masahiko
Published: May 2013

The dimerization of aryl benzyl ketones affords the required diones as diastereomeric mixtures where the racemic isomers are formed as main products.
ChemInform Abstract: Syntheses of Effectively‐Shielded N‐Heterocyclic Carbene Ligands.
Authors: Ando Shin , Matsunaga Hirofumi , Ishizuka Tadao
Published: May 2013

Newly synthesized silver—carbene complexes are applied in the copper‐catalyzed allylic arylation of cinnamyl bromide with Grignard reagent (II) to form predominantly the gamma‐product (IV).
ChemInform Abstract: Enantioselective α‐Hydroxylation of β‐Ketoamides.
Authors: De Fusco Claudia , Meninno Sara , Tedesco Consiglia , Lattanzi Alessandra
Published: May 2013

The first enantioselective α‐hydroxylation of α‐substituted β‐ketoamides such as (I) is developed furnishing tertiary alcohols in good yield and up to 83% e.e.
ChemInform Abstract: Five‐Membered 2,3‐Dioxo Heterocycles. Part 91. Reaction of 3‐Aroyl‐1H‐pyrrolo[2,1‐c][1,4]benzoxazine‐1,2,4‐triones with Dimedone. Crystalline and Molecular Structure of 3′‐Benzoyl‐4′‐hydroxy‐1′‐ (2‐hydroxyphenyl)‐6,6‐dimethyl‐6,7‐dihydrospiro [1‐benzofuran‐3,2′‐pyrrole]‐2,4,5′(1′H,5H)‐trione.
Authors: Tutynina N. M. , Racheva N. L. , Maslivets V. A. , Aliev Z. G. , Maslivets A. N.
Published: May 2013

The molecular structure of compound (III) is proved by X‐ray analysis.
ChemInform Abstract: N‐Heterocyclic Carbene‐Catalyzed Ireland—Coates Claisen Rearrangement: Synthesis of Functionalized β‐Lactones.
Authors: Candish Lisa , Lupton David W.
Published: May 2013

Formal [3 + 2]‐annulation is achieved between a range of α,β‐unsaturated acyl fluorides and cyclopropyl substrates bearing C2‐ and C4‐oxygenation.
ChemInform Abstract: Masked Amino Acid: A New C‐Nucleophile for I2‐Catalyzed Stereoselective Ring Opening of Epoxides in Ionic Liquid.
Authors: Rai Vijai K. , Sharma Roopali , Kumar Anil
Published: May 2013

Aminofuranones are prepared with excellent cis‐diastereoselectivity via ring‐opening of terminal epoxides and aminoacetylative cyclization.
ChemInform Abstract: Synthesis of 4,5,6,7‐Tetrahydro‐1H‐indole Derivatives Through Successive Sonogashira Coupling/Pd‐Mediated 5‐endo‐dig Cyclization.
Authors: Andreev Ivan A. , Belov Dmitry S. , Kurkin Alexander V. , Yurovskaya Marina A.
Published: May 2013

This is the first example of a Sonogashira coupling/cyclization sequence to yield C2‐aryl‐substituted 4,5,6,7‐tetrahydroindoles.
ChemInform Abstract: 1‐(2′‐Anilinyl)prop‐2‐yn‐1‐ol Rearrangement for Oxindole Synthesis.
Authors: Kothandaraman Prasath , Koh Bing Qin , Limpanuparb Taweetham , Hirao Hajime , Chan Philip Wai Hong
Published: May 2013

NIS‐mediated synthesis of highly functionalized gem‐3‐(diiodomethyl)indolin‐2‐ones [cf.
ChemInform Abstract: Amino‐Directed RhIII‐Catalyzed C—H Activation Leading to One‐Pot Synthesis of N—H Carbazoles.
Authors: Jiang Qibai , Duan‐Mu Dandan , Zhong Wei , Chen Hao , Yan Hong
Published: May 2013

The reaction is not sensitive to the electronic and steric effects.
ChemInform Abstract: Synthesis of 1H‐Indazoles and 1H‐Pyrazoles via FeBr3/O2 Mediated Intramolecular C—H Amination.
Authors: Zhang Tianshui , Bao Weiliang
Published: May 2013

The reaction is proposed to proceed via single‐electron‐transfer from the substrate to FeBr3.
ChemInform Abstract: Microwave Irradiated Synthesis of Some Substituted Imidazole Derivatives (IV) as Potential Antibacterial and Anticancer Agents.
Authors: Sharma Gyanendra Kumar , Sharma Naveen Kumar , Pathak Devender
Published: May 2013

All the new aryl‐substituted imidazole derivatives (IV) (10 examples) show good antibacterial activity against gram‐negative bacterial strains and significant cytotoxicity against DLA and EAC cell lines.
ChemInform Abstract: Synthesis and Antimicrobial Evaluation of Novel Lipophilic Derivatives of Pyrazolylisoxazolines.
Authors: Chadha Shally , Khajuria Rajni , Paul Satya , Kapoor Kamal K.
Published: May 2013

Pyrazolylisoxazolines bearing cyclic or linear lipophilic groups (VI) and (IX), resp., are synthesized and tested for their antibacterial and antifungal activities.
ChemInform Abstract: Synthesis and Antimicrobial Activity of 3‐(2‐Thienyl) ‐4‐arylazo‐5‐hydroxy‐5‐trifluoromethyl‐Δ2‐isoxazolines and 3‐(2‐Thienyl)‐4‐arylazo‐5‐trifluoromethylisoxazolines.
Authors: Aggarwal Ranjana , Bansal Anshul , Mittal Arpana
Published: May 2013

The title compounds (IV) and (V) exhibit moderate to significant antibacterial activity against Gram‐positive bacteria and antifungal activity against S.
ChemInform Abstract: Metal‐Free Synthesis of 2‐Aminobenzoxazoles Using Hypervalent Iodine Reagent.
Authors: Wagh Yogesh S. , Tiwari Neelam J. , Bhanage Bhalchandra M.
Published: May 2013

Uncatalyzed ring‐opening of benzoxazoles with secondary amines and subsequent oxidative cyclization of the resulting imines with IBX as the oxidant offers a convenient access to the target compounds.
ChemInform Abstract: Nano Indium Oxide as a Recyclable Catalyst for the Synthesis of Arylaminotetrazoles
Authors: Bahari Siavash , Sabegh Mehdi Ahmadi
Published: May 2013

via reaction of aryl cyanamides and sodium azide
ChemInform Abstract: Alternative Simple and Effective Synthesis of (Di)benzoxanthones and Their Functions Toward Fluorescent Dyes.
Authors: Azuma Eriko , Kuramochi Kouji , Tsubaki Kazunori
Published: May 2013

(Di)benzoxanthones are efficiently synthesized via dehydration of the corresponding dihydroxybenzophenone catalyzed simply by K2CO3 and their optical properties are investigated in MeOH.
ChemInform Abstract: Microwave‐Promoted Catalyst‐Free Benzylic C—H Functionalization of Methyl Quinoline and Michael Addition to β‐Nitrostyrene.
Authors: Rao N. Nageswara , Meshram H. M.
Published: May 2013

Functionalization of the C‐2 methyl group under conditions A) allows the rapid production of libraries containing quinoline derivatives for drug research.
ChemInform Abstract: Synthesis of Some Novel Pyrimidinedione and Pyrimidinetrione Derivatives by a Greener Method: Study of Their Antimicrobial Activity and Photophysical Properties.
Authors: Borse Bhushan Nanasaheb , Shukla Sanjeev Ramchandra , Sonawane Yogesh Ashok , Shankerling Ganpati Subray
Published: May 2013

The title compounds such as (III), (V), and (VII) are obtained by Knoevenagel condensation under classical, conventional condition, in the presence of a lipase biocatalyst or with a deep eutectic solvent (DES).
ChemInform Abstract: An Efficient, Ionic Liquid Mediated One‐Pot, Three Component Sequential Synthesis of 3‐Benzothiazolyl‐2‐styrylquinazolin‐4(3H)‐ones.
Authors: Kumar Mahendra , Sharma Kailash , Sharma Dinesh Kumar , Arya Anand Kumar
Published: May 2013

An eco‐compatible method is presented for the synthesis of title compounds (IV) (8 examples) through sequential reaction of benzoxazinone (II) with 2‐aminobenzothiazoles using the halogen‐free SO3H‐functionalized ionic liquid IMS as recyclable medium.
ChemInform Abstract: SnAP Reagents for the Transformation of Aldehydes into Substituted Thiomorpholines — An Alternative to Cross‐Coupling with Saturated Heterocycles.
Authors: Vo Cam‐Van T. , Mikutis Gediminas , Bode Jeffrey W.
Published: May 2013

Various unprotected thiomorpholine derivatives are efficiently synthesized in a one‐pot two‐step procedure from SnAP reagents (I) and (V).
ChemInform Abstract: An Efficient Synthesis and Biological Study of Substituted 8‐Chloro‐5‐methoxy/8‐Chloro‐4H‐1,4‐benzothiazines, Their Sulfones and Ribofuranosides.
Authors: Khandelwal Nishidha , Abhilasha Abhilasha , Gautam Naveen , Gautam D. C.
Published: May 2013

Novel 1,4‐benzothiazines are synthesized and tested for their antimicrobial, antifungal, and anthelmintic activity.
ChemInform Abstract: Nanostructured Sulfur Cathodes
Authors: Yang Yuan , Zheng Guangyuan , Cui Yi
Published: May 2013

Review: 109 refs.
ChemInform Abstract: Narrow Bandgap Colloidal Metal Chalcogenide Quantum Dots: Synthetic Methods, Heterostructures, Assemblies, Electronic and Infrared Optical Properties
Authors: Kershaw Stephen V. , Susha Andrei S. , Rogach Andrey L.
Published: May 2013

Review: 494 refs.
ChemInform Abstract: Advanced Oxides in Catalysis
Authors: Rossetti Ilenia
Published: May 2013

Review: 187 refs.
ChemInform Abstract: Dressed for Success — Applying Chemistry to Modulate Aptamer Functionality
Authors: Tolle Fabian , Mayer Guenter
Published: May 2013

Review: 70 refs.
ChemInform Abstract: Halogenated Quinolines as Substrates for the Palladium‐Catalyzed Cross‐Coupling Reactions to Afford Substituted Quinolines.
Authors: Mphahlele Malose J. , Lesenyeho Lehlohonolo G.
Published: May 2013

Review: 85 refs.
ChemInform Abstract: Synthesis of L‐Hexoses and Their Related Biomolecules
Authors: Zulueta Medel Manuel L. , Zhong Yong‐Qing , Hung Shang‐Cheng
Published: May 2013

Review: <65 refs.
ChemInform Abstract: BN Isosteres of Indole
Authors: Abbey Eric R. , Liu Shih‐Yuan
Published: May 2013

Review: 41 refs.
ChemInform Abstract: Synthetic Applications of Photoredox Catalysis with Visible Light
Authors: Xi Yumeng , Yi Hong , Lei Aiwen
Published: May 2013

Review: 98 refs.
ChemInform Abstract: Reactivity of Thiophenes, Oligothiophenes and Benzothiophenes
Authors: Rajappa Srinivasachari , Gumaste Vikas K.
Published: May 2013

Review: ca. 300 refs.
ChemInform Abstract: The Chemistry of Mycotoxins
Authors: Braese S. , Glaeser F. , Kramer C. S. , Lindner S. , Linsenmeier A. M. , Masters K.‐S. , Meister A. C. , Ruff B. M. , Zhong S.
Published: May 2013

Review: 789 refs.
ChemInform Abstract: Chemerin and Vaspin: Possible Targets to Treat Obesity?
Authors: Schultz Stephan , Beck‐Sickinger Annette G.
Published: May 2013

Review: ca. 100 refs.
ChemInform Abstract: Nanostructured Materials for Applications in Heterogeneous Catalysis
Authors: Zaera Francisco
Published: May 2013

Review: 252 refs.
ChemInform Abstract: The Catalytic Diversity of Zeolites: Confinement and Solvation Effects within Voids of Molecular Dimensions
Authors: Gounder Rajamani , Iglesia Enrique
Published: May 2013

Review: 146 refs.
ChemInform Abstract: Organic Sensitizers from D—π—A to D—A—π—A: Effect of the Internal Electron‐Withdrawing Units on Molecular Absorption, Energy Levels and Photovoltaic Performances
Authors: Wu Yongzhen , Zhu Weihong
Published: May 2013

Review: 76 refs.
ChemInform Abstract: Design and Development of Photoanodes for Water‐Splitting Dye‐Sensitized Photoelectrochemical Cells
Authors: Swierk John R. , Mallouk Thomas E.
Published: May 2013

Review: 324 refs.
ChemInform Abstract: Design and Functionality of Colloidal‐Crystal‐Templated Materials—Chemical Applications of Inverse Opals
Authors: Stein Andreas , Wilson Benjamin E. , Rudisill Stephen G.
Published: May 2013

Review: 289 refs.
ChemInform Abstract: Colloidal Superparticles from Nanoparticle Assembly
Authors: Wang Tie , LaMontagne Derek , Lynch Jared , Zhuang Jiaqi , Cao Y. Charles
Published: May 2013

Review: 82 refs.
ChemInform Abstract: Organic Stereochemistry. Part 2. Stereoisomerism Resulting from One or Several Stereogenic Centers
Authors: Testa Bernard
Published: May 2013

Review: 74 refs.
Coalescence and Break‐Up in Bubble Columns: Euler‐Lagrange Simulations Using a Stochastic Approach
Authors: Gruber Michael C. , Radl Stefan , Khinast Johannes G.
Published: May 2013

A systematic study of the impact of break‐up and coalescence (B&C) on the hydrodynamics in a bubble column is presented. A stochastic approach was chosen for the integration of various B&C kernels into a four‐way coupled Euler‐Lagrange model. The model is benchmarked against the Deen case, and good agreements were found for the gas holdup and the bubble size distribution. While the results indicate that monodisperse bubbles suffice to correctly forecast the flow features, B&C models are the key to predict the specific interfacial area especially in the lower half of the bubble column.
Simulation of Bubble Columns with a Compartment Model Approach
Authors: Abel Nils H. , Schlusemann Linda , Grünewald Marcus
Published: May 2013

Blasensäulenreaktoren sind zwar mechanisch einfache Apparate, die in ihnen vorherrschenden Gas‐Flüssig‐Interaktionen sind aber bedeutend komplexer. Die Auslegung anhand des axialen Dispersionsmodells hat entscheidende Nachteile in der Beschreibung der komplexen Wechselwirkungen zwischen Gas‐ und Flüssigphase. Obwohl die numerische Strömungsmechanik in den letzten Jahren, auch aufgrund steigender Rechnerkapazitäten und ‐leistungen, sehr vielversprechende Fortschritte gemacht hat, ist die Berechnung des Betriebsverhaltens industrieller Blasensäulenreaktoren nicht verifizierbar. Als Alternative bieten sich eine Unterteilung des Reaktors in Teilbilanzräume an. Diese als Kompartment‐Modellierung bekannte Beschreibungsmethode wird im Rahmen des Beitrags erläutert und diskutiert.
Unstable Manifolds of Euler Equations
Authors: Lin Zhiwu , Zeng Chongchun
Published: May 2013

We consider a steady state v0 of the Euler equation in a fixed bounded domain in ℝn. Suppose the linearized Euler equation has an exponential dichotomy of unstable and center‐stable subspaces. By rewriting the Euler equation as an ODE on an infinite‐dimensional manifold of volume‐preserving maps in Wk, q the unstable (and stable) manifolds of v0 are constructed under a certain spectral gap condition that is satisfied for both two‐dimensional and three‐dimensional examples. In particular, when the unstable subspace is finite dimensional, this implies the nonlinear instability of v0 in the sense that arbitrarily small Wk, q perturbations can lead to L2 growth of the nonlinear solutions. © 2013 Wiley Periodicals, Inc.
Fast Computation of High‐Frequency Dirichlet Eigenmodes via Spectral Flow of the Interior Neumann‐to‐Dirichlet Map
Authors: Barnett Alex , Hassell Andrew
Published: May 2013

We present a new algorithm for numerical computation of large eigenvalues and associated eigenfunctions of the Dirichlet Laplacian in a smooth, star‐shaped domain in ℝd, d ≥ 2. Conventional boundary‐based methods require a root search in eigenfrequency k, hence take O(N3) effort per eigenpair found, where N = O(kd−1) is the number of unknowns required to discretize the boundary. Our method is O(N) faster, achieved by linearizing with respect to k the spectrum of a weighted interior Neumann‐to‐Dirichlet (NtD) operator for the Helmholtz equation. Approximations to the square roots kj of all O(N) eigenvalues lying in [k − ϵ, k], where ϵ = O(1), are found with O(N3) effort. We prove an error estimate

urn:x-wiley::media:cpa21458:cpa21458-math-0002

with C independent of k. We present a higher‐order variant with eigenvalue error scaling empirically as O(ϵ5) and eigenfunction error as O(ϵ3), the former improving upon the “scaling method” of Vergini and Saraceno. For planar domains (d = 2), with an assumption of absence of spectral concentration, we also prove rigorous error bounds that are close to those numerically observed. For d = 2 we compute robustly the spectrum of the NtD operator via potential theory, Nyström discretization, and the Cayley transform. At high frequencies (400 wavelengths across), with eigenfrequency relative error 10−10, we show that the method is 103 times faster than standard ones based upon a root search. © 2014 Wiley Periodicals, Inc.
Intramolecular Hydroalkoxylation of Non‐Activated CC Bonds Catalysed by Zeolites: An Experimental and Theoretical Study
Authors: Pérez‐Mayoral Elena , Matos Ines , Nachtigall Petr , Položij Miroslav , Fonseca Isabel , Vitvarová‐Procházková Dana , Čejka Jiří
Published: May 2013

The high activity and selectivity of zeolites in the cyclisation of unsaturated alcohols is reported for the first time; the details of a reaction mechanism based on quantum chemical calculations are also provided. The high efficiency of zeolites MFI, BEA and FAU in the cyclisation of unsaturated alcohols (cis‐decen‐1‐ol, 6‐methylhept‐5‐en‐2‐ol and 2‐allylphenol) to afford oxygen‐containing heterocyclic rings is demonstrated. The best catalytic performance is found for zeolites with the optimum concentration of Brønsted acid sites (ca. 0.2 mmol g−1) and the minimum number of Lewis acid sites. It is proposed that the efficiency of the catalysts is reduced by the existence of the so‐called dual site, at which a molecule of unsaturated alcohol can simultaneously interact with two acid sites (an OH group with one and the double bond with the other Brønsted site), which increases the interaction strength. The formation of such adsorption complexes leads to a decrease in the catalyst activity because of (i) an increase in the reaction barrier, (ii) an unfavourable conformation and (iii) diffusion limitations. A new procedure for the preparation of tetrahydrofurans and pyrans over zeolite catalysts provides important oxygen‐containing heterocycles with numerous applications.
Diastereoselective Synthesis of Isoindole‐Fused Diazacyclooctaindenones from Spiro­chromenes through Domino Reactions with Aliphatic 1,2‐Diamines
Authors: Pathak Sudipta , Pramanik Animesh
Published: May 2013

A diastereoselective synthesis of isoindole‐fused diazacyclooctaindenone derivatives has been accomplished through tandem ring‐opening and ring‐closing of spirochromene derivatives triggered by different aliphatic 1,2‐diamines. When ethanolic solutions of spirochromenes are refluxed with different aliphatic 1,2‐diamines such as 1,2‐ethylenediamine, (±)‐1,2‐propylenediamine and (±)‐trans‐1,2‐cyclohexanediamine, the isoindole‐fused eight‐membered heterocycles are formed in moderate to high yields within 5–15 min.
Equilibrative nucleoside transporter (ENT)-1-dependent elevation of extracellular adenosine protects the liver during ischemia and reperfusion
Authors: Zimmerman Michael A. , Tak Eunyoung , Ehrentraut Stefan F. , Kaplan Maria , Giebler Antasia , Weng Tingting , Choi Doo-Sup , Blackburn Michael R. , Kam Igal , Eltzschig Holger K. , Grenz Almut
Published: May 2013

Ischemia and reperfusion-elicited tissue injury contributes to morbidity and mortality of hepatic surgery and during liver transplantation. Previous studies implicated extracellular adenosine signaling in liver protection. Based on the notion that extracellular adenosine signaling is terminated by uptake from the extracellular towards the intracellular compartment by way of equilibrative nucleoside transporters (ENTs), we hypothesized a functional role of ENTs in liver protection from ischemia. During orthotopic liver transplantation in humans, we observed higher expressional levels of ENT1 than ENT2, in conjunction with repression of ENT1 and ENT2 transcript and protein levels following warm ischemia and reperfusion. Treatment with the pharmacologic ENT inhibitor dipyridamole revealed elevations of hepatic adenosine levels and robust liver protection in a murine model of liver ischemia and reperfusion. Studies in gene-targeted mice for

Ent1

or

Ent2

demonstrated selective protection from liver injury in

Ent1

−/− mice. Treatment with selective adenosine receptor antagonists indicated a contribution of Adora2b receptor signaling in ENT-dependent liver protection.

Conclusion:

These findings implicate ENT1 in liver protection from ischemia and reperfusion injury and suggest ENT inhibitors may be of benefit in the prevention or treatment of ischemic liver injury. (Hepatology 2013;58:1766–1778)
Association of IL28B genotype with fibrosis progression and clinical outcomes in patients with chronic hepatitis C: A longitudinal analysis
Authors: Noureddin Mazen , Wright Elizabeth C. , Alter Harvey J. , Clark Shauna , Thomas Emmanuel , Chen Richard , Zhao Xiongce , Conry-Cantilena Cathy , Kleiner David E. , Liang Jake T. , Ghany Marc G.
Published: May 2013

Interleukin (IL)28B polymorphisms are associated with spontaneous clearance of hepatitis C virus (HCV) infection and response to therapy. Whether IL28B genotype affects fibrosis progression or clinical outcome is unclear. Our aim was to study the relationship between IL28B genotype and both histological and clinical outcomes in patients with chronic hepatitis C (CHC). Hepatic fibrosis was scored using the Ishak (0-6) scale; progression was defined as a 2-point increase in Ishak score between biopsies. Multiple logistic and Cox regressions were used to identify variables associated with fibrosis progression. In all, 1,483 patients were included in a baseline cross-sectional analysis, from which 276 were eligible for a paired biopsy analysis (median time between biopsies 4 years), and 400 for a clinical outcome analysis. At baseline biopsy, patients with IL28B CC genotype had significantly higher portal inflammation (2.4 versus 2.2) and alanine aminotransferase (ALT) levels (133 versus 105 U/L;

P

< 0.05 for all). In the paired biopsy analysis, there was no difference in the frequency of fibrosis progression between patients with IL28B CC and non-CC genotypes (17% versus 23%). In logistic regression, only higher baseline alkaline phosphatase, lower platelets, and greater hepatic steatosis were associated with fibrosis progression. Patients with IL28B CC were twice as likely to develop adverse clinical outcomes compared to non-CC (32% versus 16%;

P

= 0.007).

Conclusion:

IL28B CC genotype was associated with greater hepatic necroinflammation, higher ALT, and worse clinical outcomes in CHC patients. This suggests that IL28B CC is associated with a state of enhanced immunity that, on the one hand, can promote viral clearance, but alternately can increase necroinflammation and hepatic decompensation without enhancing fibrosis progression. (Hepatology 2013;58:1548–1557)
Diastolic dysfunction is a predictor of poor outcomes in patients with cirrhosis, portal hypertension, and a normal creatinine
Authors: Ruíz-del-Árbol Luís , Achécar Linette , Serradilla Regina , Rodríguez-Gandía Miguel Á. , Rivero Miguel , Garrido Elena , Natcher José J.
Published: May 2013

We investigated left ventricular diastolic dysfunction (LVDD) and its relationship with circulatory function and prognosis in cirrhosis with portal hypertension and normal creatinine. Conventional and tissue Doppler (TDI) echocardiography, systemic and hepatic hemodynamics, and the activity of endogenous vasoactive systems (AEVS) were measured prospectively in 80 patients. Plasma renin activity (PRA; >4 ng/mL/hour) was used as a surrogate of effective arterial blood volume. Patients were followed up for 12 months. Thirty-seven patients had LVDD (19 with grade 1 and 18 with grade 2). Left ventricular hypertrophy, left atrial volume, AEVS, and natriuretic peptide levels were significantly greater in patients with LVDD than without LVDD. Patients with grade 2 LVDD, compared to grade 1 LVDD and without LVDD, had significantly lower mean arterial pressure and higher Model for End-Stage Liver Disease (MELD) score, E-wave transmitral/early diastolic mitral annular velocity (E/e′ ratio), cardiopulmonary pressures, PRA, and natriuretic peptide levels. Systolic and cardiac chronotropic function were significantly lower in patients with grade 2 LVDD than without LVDD. LVDD was more frequent in patients with ascites and increased PRA than patients without ascites or with ascites but normal PRA. Fourteen patients with LVDD developed hepatorenal syndrome (HRS) type 1 on follow-up. Survival was different according to degree of LVDD (without LVDD: 95%; grade 1 LVDD: 79%; grade 2 LVDD: 39%;

P

< 0.001). Independent predictive factors of mortality were MELD score and E/e′ ratio.

Conclusion:

LVDD occurs simultaneously with other changes in cardiac structure and function and is associated with an impairment of effective arterial blood volume. LVDD is a sensitive marker of advanced cirrhosis, type 1 HRS development, and mortality. (Hepatology 2013;58:1732–1741)
Prothrombotic factors in histologically proven nonalcoholic fatty liver disease and nonalcoholic steatohepatitis
Authors: Verrijken An , Francque Sven , Mertens Ilse , Prawitt Janne , Caron Sandrine , Hubens Guy , Van Marck Eric , Staels Bart , Michielsen Peter , Van Gaal Luc
Published: May 2013

An independent role of nonalcoholic fatty liver disease (NAFLD) in the development of cardiovascular disease has been suggested, probably mediated through increased levels of prothrombotic factors. Therefore, we examined whether NAFLD is linked to a prothrombotic state, independently of metabolic risk factors in a large single-center cohort of overweight/obese patients. Patients presenting to the obesity clinic underwent a detailed metabolic and liver assessment, including an extensive panel of coagulation factors. If NAFLD was suspected, a liver biopsy was proposed. A series of 273 consecutive patients (65% female) with a liver biopsy were included (age, 44 ± 0.76 years; body mass index: 39.6 ± 0.40 kg/m2). Increase in fibrinogen, factor VIII, and von Willebrand factor and decrease in antithrombin III correlated with metabolic features, but not with liver histology. Levels of plasminogen activator inhibitor-1 (PAI-1) increased significantly with increasing severity of steatosis (

P

< 0.001), lobular inflammation (

P

< 0.001), ballooning (

P

= 0.002), and fibrosis (

P

< 0.001). Patients with nonalcoholic steatohepatitis had significantly higher PAI-1 values than those with normal liver (

P

< 0.001). In multiple regression, including anthropometric and metabolic parameters, steatosis remained an independent predictor of PAI-1 levels, explaining, together with fasting C-peptide and waist circumference, 21% of the variance in PAI-1. No consistent correlations with histology were found for the other coagulation factors.

Conclusion :

In obesity, NAFLD severity independently contributes to the increase in PAI-1 levels, whereas other coagulation factors are unaltered. This finding might, in part, explain the increased cardiovascular risk associated with NAFLD.