bluuebunny/crossref_metadata_2025 huggingface dataset:
Connected flow paths as first order control on critical zone water flows: coincidence or self-organized optimality?
Authors: Zehe E. , Blume T. , Kleidon A. , Ehret U. , Scherer U. , Westhoff M.
Published: September 2012

Abstract. This study proposes a theoretical framework that links hydrological dynamics to thermodynamics, with emphasis on dynamics and dissipation of free energy and production of entropy in the critical zone. Based on this theory we analyse simulations with a physically based hydrological model in the Weiherbach and the Malalcahuello catchments to learn about free energy dynamics and entropy production in these different hydro-climatic and hydro-pedological settings. Results for the Weiherbach catchment suggest the existence of a thermodynamic optimal hillslope structure as a result of co-evolution of biotic patterns and the soil catena. This optimum structure allowed acceptable un-calibrated reproduction of observed rainfall-runoff behaviour when being used in a catchment model – in fact it came close to the best fit. Results corroborate furthermore that connected network-like structures – vertical preferential pathways and the river network in this case – act as dissipative structures by accelerating flow against driving gradients, which implies accelerated entropy production. For the Malalcahuello catchment we found that maximum drainage is the functional optimum hillslope structure. This is explained by the very wet, energy limited climate, the presence of non-cohesive highly permeable ash soils and the different mechanism causing preferential flow.
Agricultural groundwater management in the Upper Bhima Basin, India: current status and future scenarios
Authors: Surinaidu L. , Bacon C. G. D. , Pavelic P.
Published: September 2012

Abstract. The basaltic aquifers of the Upper Bhima River Basin in Southern India are heavily utilized for small-scale agriculture but face increasing demand-related pressures along with uncertainty associated with climate change impacts. To evaluate likely groundwater resource impacts over the coming decades, a regional groundwater flow model for the basin was developed. Model predictions of different climate change and abstraction scenarios indicate continuation of current rates of abstraction would lead to significant groundwater overdraft, with groundwater elevations predicted to fall by −6 m over the next three decades. Groundwater elevations can however be stabilized, but would require 20–30% of the mean surface water discharge from the basin to be recharged to groundwater, along with reductions in pumping (5–10%) brought about by improved water efficiency practices and/or shifts towards lower-water use crops. Modest reductions in pumping alone cannot stabilize groundwater levels; targeted conjunctive use and improved water use efficiency are also needed.
Differential Expression Analysis for RNA-Seq Data
Authors: Gupta Rashi , Dewan Isha , Bharti Richa , Bhattacharya Alok
Published: September 2012

RNA-Seq is increasingly being used for gene expression profiling. In this approach, next-generation sequencing (NGS) platforms are used for sequencing. Due to highly parallel nature, millions of reads are generated in a short time and at low cost. Therefore analysis of the data is a major challenge and development of statistical and computational methods is essential for drawing meaningful conclusions from this huge data. In here, we assessed three different types of normalization (transcript parts per million, trimmed mean of M values, quantile normalization) and evaluated if normalized data reduces technical variability across replicates. In addition, we also proposed two novel methods for detecting differentially expressed genes between two biological conditions: (i) likelihood ratio method, and (ii) Bayesian method. Our proposed methods for finding differentially expressed genes were tested on three real datasets. Our methods performed at least as well as, and often better than, the existing methods for analysis of differential expression.
Fetal Nucleic Acids in Maternal Circulation: A Genetic Resource for Noninvasive Prenatal Diagnosis
Authors: Banerjee Monisha , Misra Deepika
Published: September 2012

Invasive prenatal diagnosis (PND) holds a multitude of psychological considerations for women, their partners, family and community as a whole. Earlier, the non-invasive screening methods for certain disorders were serum analytes or ultrasound with low sensitivity and high false positivity. The discovery of fetal DNA in maternal plasma has opened up an approach for noninvasive PND (NIPD). Presence of fetal cells and cell-free fetal DNA (cffDNA) in the blood of pregnant women has been accepted universally and constant efforts are being made to enrich fetal DNA from maternal blood/plasma. Real-time quantitative polymerase chain reaction (qrt-PCR) has enabled fetal DNA to serve as a marker for chromosomal abnormalities, for example, trisomy 21, preterm labor, and preeclampsia. In India, PND is provided in few centers since invasive methods require trained gynecologists, this limits investigation and therefore NIPD with cffDNA from mother's blood will revolutionize fetal medicine. The present paper deals with the latest developments in procurement of cffDNA, the probable source and enrichment of fetal DNA in maternal plasma, and the current status of its detection methodologies, applications, and its potential to be used as a powerful diagnostic tool.
Gestion positive des situations de classe : un modèle de formation en cours d’emploi pour aider les enseignants du primaire à prévenir les comportements difficiles des élèves
Authors: Gaudreau Nancy , Royer Égide , Beaumont Claire , Frenette Éric
Published: September 2012

Plusieurs auteurs dénoncent depuis quelques années le manque de formation des enseignants pour gérer efficacement les comportements difficiles des élèves. Afin de soutenir la réussite des élèves qui présentent des difficultés de comportement, il s’avère essentiel de développer des modèles de formation en cours d’emploi qui répondent aux besoins des enseignants. Cet article présente le programme de formation à la gestion positive des situations de classe (GPS), spécialement conçu pour les enseignants du premier cycle du primaire à partir des données probantes de recherches dans le domaine. Il vise le développement des compétences professionnelles des enseignants en matière de gestion de la classe et des comportements difficiles. Les formules pédagogiques proposées ont pour but de soutenir le développement des croyances d’efficacité personnelle chez les enseignants afin de favoriser l’implantation de pratiques éducatives permettant de prévenir les comportements difficiles et de les gérer efficacement en classe.
Preferred antiretroviral drugs for the next decade of scale up
Authors: Andrieux‐Meyer Isabelle , Calmy Alexandra , Cahn Pedro , Clayden Polly , Raguin Gilles , Katlama Christine , Vitoria Marco , Levin Andrew , Lynch Sharonann , Goemaere Eric , Ford Nathan ,   participants of the Art Sequencing meeting September 22–23 2011, Geneva, Switzerland
Published: September 2012

Global commitments aim to provide antiretroviral therapy (ART) to 15 million people living with HIV by 2015, and recent studies have demonstrated the potential for widespread ART to prevent HIV transmission. Increasingly, countries are adapting their national guidelines to start ART earlier, for both clinical and preventive benefits. To maximize the benefits of ART in resource‐limited settings, six key principles need to guide ART choice: simplicity, tolerability and safety, durability, universal applicability, affordability and heat stability. Currently available drugs, combined with those in late‐stage clinical development, hold great promise to simplify treatment in the short term. Over the longer term, newer technologies, such as long‐acting formulations and nanotechnology, could radically alter the treatment paradigm. This commentary reviews recommendations made in an expert consultation on treatment scale up in resource‐limited settings.
Studies on the surface properties of mixed‐matrix membrane and its antifouling properties for humic acid removal
Authors: Teow Y. H. , Ahmad A. L. , Lim J. K. , Ooi B.S.
Published: September 2012

A major factor limiting the use of ultrafiltration (UF) membrane in water treatment process is the membrane fouling by natural organic matter such as humic acid (HA). In this work, neat PVDF and PVDF/TiO2 mixed‐matrix membranes were prepared and compared in terms of their antifouling properties. Two commercial types of TiO2 namely PC‐20 and P25 were embedded to prepare the mixed matrix membranes via in situ colloidal precipitation method. The contact angles for the mixed‐matrix membranes were slightly reduced while the zeta potential was increased (more negatively charged) compared with the neat membrane. Filtration of HA with the presence of Ca2+ demonstrated that mixed‐matrix membrane could significantly mitigate the fouling tendency compared with the neat membrane with flux ratio (J/J0) of 0.65, 0.70, and 0.82 for neat PVDF membrane, PVDF/TiO2 mixed‐matrix membrane embedded with P25 and PC‐20, respectively. PC‐20 with higher anatase polymorphs exhibited better antifouling properties due to its hydrophilicity nature. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Ethylene‐methyl acrylate‐glycidyl methacrylate toughened poly(lactic acid) nanocomposites
Authors: Baouz Touffik , Rezgui Farouk , Yilmazer Ulku
Published: September 2012

Poly (lactic acid) (PLA) was melt blended in a twin screw extruder using an ethylene‐methyl acrylate‐glycidyl methacrylate rubber as a toughener. PLA/rubber blends were immiscible as observed by scanning electron microscopy. Impact strength and ductility of PLA were improved by the addition of the rubber at the expense of strength and stiffness. An organo‐montmorillonite (OMMT) was used at 2 wt % to counteract the negative effect of the rubber on modulus, and balanced properties were observed at 10 wt % rubber content. X‐ray diffraction and transmission electron microscopy revealed the formation of intercalated/exfoliated structure in the ternary nanocomposites. Thermal behavior analysis indicated that the degree of crystallinity is slightly affected by the clay and the rubber. Both the clay and the rubber decreased the crystallization temperature of PLA and acted as nucleating agents for PLA. The viscosity of the mixtures as measured by melt flow index was highly influenced by the rubber and the OMMT. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013
Controlling the Self‐Assembly of a Mixed‐Metal Mo/V–Selenite Family of Polyoxometalates
Authors: Corella‐Ochoa M. Nieves , Miras Haralampos N. , Long De‐Liang , Cronin Leroy
Published: September 2012

Five mixed‐metal mixed‐valence Mo/V polyoxoanions, templated by the pyramidal SeO32− heteroanion have been isolated: K10[MoVI12VV10O58(SeO3)8]⋅18 H2O (1), K7[MoVI11VV5VIV2O52(SeO3)]⋅31 H2O (2), (NH4)7K3[MoVI11VV5VIV2O52(SeO3)(MoV6VV‐ O22)]⋅40 H2O (3), (NH4)19K3[MoVI20VV12VIV4O99(SeO3)10]⋅36 H2O (4) and [Na3(H2O)5{Mo18−xVxO52(SeO3)} {Mo9−yVyO24(SeO3)4}] (5). All five compounds were characterised by single‐crystal X‐ray structure analysis, TGA, UV/Vis and FT‐IR spectroscopy, redox titrations, and elemental and flame atomic absorption spectroscopy (FAAS) analysis. X‐ray studies revealed two novel coordination modes for the selenite anion in compounds 1 and 4 showing η,μ and μ,μ coordination motifs. Compounds 1 and 2 were characterised in solution by using high‐resolution ESI‐MS. The ESI‐MS spectra of these compounds revealed characteristic patterns showing distribution envelopes corresponding to 2− and 3− anionic charge states. Also, the isolation of these compounds shows that it may be possible to direct the self‐assembly process of the mixed‐metal systems by controlling the interplay between the cation “shrink‐wrapping” effect, the non‐conventional geometry of the selenite anion and fine adjustment of the experimental variables. Also a detailed IR spectroscopic analysis unveiled a simple way to identify the type of coordination mode of the selenite anions present in POM‐based architectures.
Mechanistic Studies on the Gas‐Phase Dehydrogenation of Alkanes at Cyclometalated Platinum Complexes
Authors: Butschke Burkhard , Schwarz Helmut
Published: September 2012

In the ion/molecule reactions of the cyclometalated platinum complexes [Pt(LH)]+ (L=2,2′‐bipyridine (bipy), 2‐phenylpyridine (phpy), and 7,8‐benzoquinoline (bq)) with linear and branched alkanes CnH2n+2 (n=2–4), the main reaction channels correspond to the eliminations of dihydrogen and the respective alkenes in varying ratios. For all three couples [Pt(LH)]+/C2H6, loss of C2H4 dominates clearly over H2 elimination; however, the mechanisms significantly differs for the reactions of the “rollover”‐cyclometalated bipy complex and the classically cyclometalated phpy and bq complexes. While double hydrogen‐atom transfer from C2H6 to [Pt(bipyH)]+, followed by ring rotation, gives rise to the formation of [Pt(H)(bipy)]+, for the phpy and bq complexes [Pt(LH)]+, the cyclometalated motif is conserved; rather, according to DFT calculations, formation of [Pt(LH)(H2)]+ as the ionic product accounts for C2H4 liberation. In the latter process, [Pt(LH)(H2)(C2H4)]+ (that carries H2 trans to the nitrogen atom of the heterocyclic ligand) serves, according to DFT calculation, as a precursor from which, due to the electronic peculiarities of the cyclometalated ligand, C2H4 rather than H2 is ejected. For both product‐ion types, [Pt(H)(bipy)]+ and [Pt(LH)(H2)]+ (L=phpy, bq), H2 loss to close a catalytic dehydrogenation cycle is feasible. In the reactions of [Pt(bipyH)]+ with the higher alkanes CnH2n+2 (n=3, 4), H2 elimination dominates over alkene formation; most probably, this observation is a consequence of the generation of allyl complexes, such as [Pt(C3H5)(bipy)]+. In the reactions of [Pt(LH)]+ (L=phpy, bq) with propane and n‐butane, the losses of the alkenes and dihydrogen are of comparable intensities. While in the reactions of “rollover”‐cyclometalated [Pt(bipyH)]+ with CnH2n+2 (n=2–4) less than 15 % of the generated product ions are formed by CC bond‐cleavage processes, this value is about 60 % for the reaction with neo‐pentane. The result that CC bond cleavage gains in importance for this substrate is a consequence of the fact that 1,2‐elimination of two hydrogen atoms is no option; this observation may suggest that in the reactions with the smaller alkanes, 1,1‐ and 1,3‐elimination pathways are only of minor importance.
Wrapping an Organic Reducing Reagent in a Cationic Boron Complex and Its Use in the Synthesis of Polyhalide Monoanionic Networks
Authors: Vitske Viktoriia , Herrmann Hendrik , Enders Markus , Kaifer Elisabeth , Himmel Hans‐Jörg
Published: September 2012

The reaction between BF3⋅OEt2 and one of two guanidines, 1,8‐bis(tetramethylguanidinyl)naphthalene (btmgn) and 1,2,4,5‐tetrakis(tetramethylguanidinyl)naphthalene (ttmgn), yields the salts [(btmgn)(BF2)]BF4 and [(ttmgn)(BF2)2](BF4)2. NMR spectroscopic data show that the boron atoms in the cation and anion exchange in the case of [(ttmgn)(BF2)2](BF4)2, but not in the case of [(btmgn)(BF2)]BF4. The rate constant for this exchange was estimated to be 4 s−1 at 80 °C for solutions in CH3CN. These salts were subsequently used for the reduction of dihalides Br2 or I2 to give polyhalide salts. We report the synthesis and first complete characterization (including structural analysis) of salts that contain pentabromide monoanions. In these salts, the Br5− anions interact to give dimeric units or polymeric chains. Our results are compared to previous quantum chemical calculations on the gas‐phase structure of the Br5− anion. The possible pathways that lead to the polyhalides are evaluated. In the case of [(ttmgn)(BF2)2](BF4)2, reduction is accompanied by ttmgn oxidation, whereas in the case of [(btmgn)(BF2)]BF4 reduction is initiated by aromatic substitution.
Dual Hard/Soft Gold Catalysis: Intermolecular Friedel–Crafts‐Type α‐Amidoalkylation/Alkyne Hydroarylation Sequences by N‐Acyliminium Ion Chemistry
Authors: Boiaryna Liliana , El Mkaddem Mohamed Kamal , Taillier Catherine , Dalla Vincent , Othman Mohamed
Published: September 2012

Gold catalysts have been applied in cascade‐type reactions for the synthesis of different nitrogen‐based compounds. The reactions likely proceed by a new gold‐catalyzed cascade intermolecular α‐amidoalkylation/intramolecular carbocyclization cascade process by unifying both the σ‐ and π‐Lewis acid properties of the gold salts. In the first part of this report we show that the σ‐Lewis acidity of gold(I) and gold(III) could be exploited to efficiently catalyze the nucleophilic substitution of various alkoxy‐ and acetoxylactams. The reaction was found to be applicable to a wide range of cyclic N‐acyliminium ion precursors and various nucleophiles, including allyltrimethylsilane, silyl enol ethers, arenes, and active methylene derivatives. As a logical progression of this study, a combined hard/soft binary catalytic gold system was then used to implement an unprecedented tandem intermolecular Friedel–Crafts amidoalkylation/intramolecular hydroarylation sequence allowing an expedient access to new, complex, fused polyheterocyclic structures from trivial materials.
Synthesis of 11‐cis‐Retinoids by Hydrosilylation–Protodesilylation of an 11,12‐Didehydro Precursor: Easy Access to 11‐ and 12‐Mono‐ and 11,12‐Dideuteroretinoids
Authors: Bergueiro Julián , Montenegro Javier , Saá Carlos , López Susana
Published: September 2012

An expeditious, highly efficient approach to 11‐cis‐retinoids was achieved by semihydrogenation of a readily available 11‐yne precursor through a hydrosilylation–protodesilylation protocol. The complete chemo‐, regio‐, and syn‐stereoselectivity of the method also allowed direct access to 11‐ and 12‐monodeutero‐, and 11,12‐dideutero‐11‐cis‐retinoids. The analogous trans series was not accessible by this route, and was synthesized by means of Hiyama coupling.
ChemInform Abstract: Solid Solutions RE16Rh11‐xZx (RE: La, Ce, Pr, Nd, Sm; Z: Ga, Zn, Cd, In, Sn, Sb, Pb, Bi) — Centrosymmetric n = 2 Variants of Parthe′s Homologous Series A5n+6B3n+5.
Authors: Tappe Frank , Schappacher Falko M. , Langer Thorsten , Schellenberg Inga , Poettgen Rainer
Published: September 2012

The title solid solutions are prepared by high‐frequency melting of the elements in sealed Ta ampules and characterized by powder XRD.
ChemInform Abstract: Li0.97FeII0.79Fe III0.15(PO4), a New Oxidized Triphylite‐Type Phosphate.
Authors: Dal Bo Fabrice , Hatert Frederic
Published: September 2012

The mixed valence title compound is hydrothermally synthesized from an aqueous mixture of Li3PO4, FePO4, and Fe in a 4:2:1 molar ratio (autoclave, 0.1 GPa, 973 K, 7 d).
ChemInform Abstract: Synthesis, Crystal Structure and Properties of a New Lead Calcium Diborate.
Authors: Cao Jian , Pan Shilie , Gao Junyu , Huang Zhenjun , Dong Xiaoyu , Zhang Min
Published: September 2012

Single crystals of the new compound PbCaB2O5 are synthesized by the spontaneous crystallization method from a mixture of PbO, H3BO3, and CaF2 (Pt crucible, 700 °C, 1 d).
ChemInform Abstract: Catalytic C—H Oxidation by a Triazamacrocyclic Ruthenium Complex.
Authors: McNeill Eric , Du Bois J.
Published: September 2012

An efficient bench‐stable, easily prepared catalyst is presented in the title reaction.
ChemInform Abstract: Pyridinium o‐Iodoxybenzoate as a Safe Form of a Famous Oxidant.
Authors: Kumanyaev Ivan M. , Lapitskaya Margarita A. , Vasiljeva Ljudmila L. , Pivnitsky Kasimir K.
Published: September 2012

Readily available PIBX can serve as a convenient substitute of the widely‐used oxidant IBX for the oxidation of alcohols to the corresponding carbonyl compounds.
ChemInform Abstract: High‐Yielding, Versatile, and Practical [Rh(III)Cp*]‐Catalyzed ortho Bromination and Iodination of Arenes.
Authors: Schroeder Nils , Wencel‐Delord Joanna , Glorius Frank
Published: September 2012

The title reaction is compatible not only with the bromination and iodination of tertiary benzamide substrates bearing a variety of electron‐rich and electron‐poor groups but also with other classes of arenes, such as secondary benzamides, acetamides, and phenylpyridines.
ChemInform Abstract: Samarium‐Promoted Asymmetric Aldol—Tishchenko Reaction: Synthesis of Amino Acid‐Derived 4‐Amino‐1,3‐diols.
Authors: Rodriguez‐Solla Humberto , Concellon Carmen , Tuya Paula , Garcia‐Granda Santiago , Diaz M. Rosario
Published: September 2012

Enantiopure title compounds (V) are obtained after reduction of aldol—Tishchenko adducts formed with moderate diastereoselectivity from chiral amino ketones (I) and aliphatic aldehydes.
ChemInform Abstract: New Chiral Phase‐Transfer Catalysts Possessing a 6,6′‐Bridged Ring on the Biphenyl Unit: Application to the Synthesis of α,α‐Dialkyl‐α‐amino Acids.
Authors: Kubota Yasushi , Shirakawa Seiji , Inoue Tsutomu , Maruoka Keiji
Published: September 2012

Powerful chiral biphenyl catalysts possessing a 6,6′‐bridged ring on the biphenyl unit are designed and successfully applied to the enantioselective synthesis of amino acids having a quaternary stereocenter.
ChemInform Abstract: Organocatalyzed Isomerization of α‐Substituted Alkynoates into Trisubstituted Allenoates by Dynamic Kinetic Resolution.
Authors: Inokuma Tsubasa , Furukawa Masaya , Suzuki Yusuke , Kimachi Tetsutaro , Kobayashi Yusuke , Takemoto Yoshiji
Published: September 2012

The isomerization of alkynoates is smoothly catalyzed by a bicyclic guanidine—diamine catalyst to afford the trisubstituted allenoates (II) in high enantioselectivities (up to 94% e.e.).
ChemInform Abstract: Decarboxylative Bromination of Cinnamic Acids by 2‐Iodoxybenzoic Acid with Tetrabutylammonium Bromide.
Authors: Han Jianlei , Wei Yuping
Published: September 2012

The bromides of type (II) are useful coupling components for transition‐metal catalyzed reactions.
ChemInform Abstract: S‐Benzyl Isothiouronium Chloride as a Recoverable Organocatalyst for the Direct Reductive Amination of Ketones with Hantzsch Ester.
Authors: Nguyen Quynh Pham Bao , Kim Taek Hyeon
Published: September 2012

The procedure is successful for various ketones and aromatic amines to afford the desired products in moderate to good yield.
ChemInform Abstract: Zinc‐Catalyzed Oxidative Esterification of Aromatic Aldehydes.
Authors: Wu Xiao‐Feng
Published: September 2012

Best results are obtained with MeOH.
ChemInform Abstract: Chemoselective Suzuki—Miyaura Coupling of Bromophenyl‐Substituted Bromoallenes with Arylboronic Acids.
Authors: Du Xin , Liu Xuesong , Xu Liang , Jiang Wenfeng , Bao Ming , He Ren
Published: September 2012

It discovered that reaction of allenes of type (I) with arylboronic acids under the conditions shown exclusively takes place at the brominated double bond and not at the bromophenyl substituent.
ChemInform Abstract: Sonogashira Reactions of 2,3,4,5‐Tetrabromofuran: Synthesis of 2,3,4,5‐Tetraalkynylfurans, 2,3,5‐Trialkynylfurans and 2,5‐Dialkynylfurans.
Authors: Malik Imran , Ahmad Zeeshan , Reimann Sebastian , Nawaz Muhammed , Patonay Tamas , Langer Peter
Published: September 2012

Pd/Cu‐catalyzed regioselective Sonogashira cross‐coupling of (I) with acetylenes using diisopropylamine as base and solvent provides di‐, tri‐ and tetraalkynylated furans.
ChemInform Abstract: Synthesis of Functionalized 2,5‐Diaminofurans by Reaction of Isocyanides, Acetylenic Esters and Acid Anhydrides.
Authors: Hassanabadi Alireza , Mosslemin Mohammad H. , Anary‐Abbasinejad Mohammad , Ghalehbandy Sharminehsadat
Published: September 2012

The advantages of the presented protocol are mild reaction conditions, short reaction time and the tolerance of various functional groups.
ChemInform Abstract: Hindered Biaryls by C—H Coupling: Bisoxazoline‐Pd Catalysis Leading to Enantioselective C—H Coupling.
Authors: Yamaguchi Kazuya , Yamaguchi Junichiro , Studer Armido , Itami Kenichiro
Published: September 2012

The first enantioselective biaryl coupling through C—H bond functionalization is demonstrated [cf.
ChemInform Abstract: Synthesis of Unprotected Carboxy Indazoles via Pd‐Catalyzed Carbonylation.
Authors: Wainwright Philip , et al. et al.
Published: September 2012

The first synthesis of unprotected indazolecarboxylates from corresponding bromoindazoles is achieved using Pd‐catalyzed carbonylation reactions.
ChemInform Abstract: Synthesis of Cyanoacetyl Oxazolidinones.
Authors: Weeber Kaitlyn M. , Schwarz Jacob B.
Published: September 2012

Chloroacetyl imides derived from chiral oxazolidinones react with cyanide to give the title compounds (III).
ChemInform Abstract: Potassium tert‐Butoxide Promoted Cycloaddition Reaction for the Synthesis of 1,5‐Disubstituted 1,2,3‐Triazoles from Aromatic Azides and Trimethylsilyl‐Protected Alkynes.
Authors: Wu Luyong , Chen Yuxue , Tang Mi , Song Xinming , Chen Guangying , Song Xiaoping , Lin Qiang
Published: September 2012

Optimized conditions are developed for the desilylation of the starting alkynes and subsequent cycloaddition with aromatic azides to produce triazoles regioselectively.
ChemInform Abstract: Chemoselective Suzuki—Miyaura Reactions of 4‐Trifluoromethylsulfonyloxy‐6‐bromocoumarin.
Authors: Akrawi Omer A. , Nagy Gergo Z. , Patonay Tamas , Villinger Alexander , Langer Peter
Published: September 2012

A broad spectrum of biologically interesting mono‐ and diarylated coumarin derivatives is prepared.
ChemInform Abstract: A Convenient Synthesis of (1H‐Azol‐1‐yl)piperidines.
Authors: Shevchuk Nadiia V. , Liubchak Kostiantyn , Nazarenko Kostiantyn G. , Yurchenko Aleksandr A. , Volochnyuk Dmitriy M. , Grygorenko Oleksandr O. , Tolmachev Andrey A.
Published: September 2012

A convenient two‐step sequence including heteroarylation of azoles and subsequent reduction allows the synthesis of various N‐heterocyclic systems as potential drug candidates.
ChemInform Abstract: Efficient Synthesis of N‐Substituted 4‐Arylquinoline Derivatives Using ZnCl2 or ZrO2.
Authors: Zonouzi Afsaneh , Mirzazadeh Roghieh , Peivandi Azadeh , Dehdari Shahrzad
Published: September 2012

A new modification of Hantzsch dihydropyridine synthesis is given using either zinc chloride or zirconium(IV) oxide as inexpensive Lewis acid catalysts.
ChemInform Abstract: Gold‐Catalyzed Cascade Reaction of Hydroxy Enynes for the Synthesis of Oxanorbornenes and Naphthalene Derivatives.
Authors: Song Xian‐Rong , Xia Xiao‐Feng , Song Qing‐Bao , Yang Fang , Li Ying‐Xiu , Liu Xue‐Yuan , Liang Yong‐Min
Published: September 2012

Treatment of the enynes with [bmim]AuCl4 results in efficient formation of oxanorbornene derivatives.
ChemInform Abstract: Synthesis of Novel Tricyclic and Tetracyclic Sultone Scaffolds via Intramolecular 1,3‐Dipolar Cycloaddition Reactions.
Authors: Ghandi Mehdi , Taheri Abuzar , Bozcheloei Abolfazl Hasani , Abbasi Alireza , Kia Reza
Published: September 2012

This are the first examples for cycloadditions in which the dipolarophile is tethered to the dipole moiety by a sulfonate link.
ChemInform Abstract: Synthesis and Structure Analysis of 1‐(2‐Chlorobenzoyl)‐3,6‐diphenyl‐1,4‐dihydro‐1,2,4,5‐tetrazine.
Authors: Rao Guo‐Wu , Zhang Li‐Ling , Li Xiao‐Min
Published: September 2012

The title reaction leads to the 1,4‐dihydro rather than the 1,2‐dihydro derivative.
ChemInform Abstract: An Efficient One‐Pot Synthesis, Structure, Antimicrobial and Antioxidant Investigations of Some Novel Quinolyldibenzo[b,e][1,4]diazepinones.
Authors: Parmar Narsidas J. , Barad Hitesh A. , Pansuriya Bhavesh R. , Teraiya Shashikant B. , Gupta Vivek K. , Kant Rajni
Published: September 2012

A catalyst‐ and solvent‐free procedure for the one‐pot synthesis of novel N‐allylated quinolyldibenzodiazepinones via a multicomponent reaction is developed.
ChemInform Abstract: Synthesis of Novel Pyrido[1,2‐b][2,4]benzodiazepine Derivatives.
Authors: Kovtunenko Volodymyr O. , Potikha Lyudmila M. , Sypchenko Volodymyr V. , Zubatyuk Roman I. , Shishkin Oleg V.
Published: September 2012

The title compounds (IV) are stable on heating with Ac2O, Ph—NO2, benzaldehydes and amines but undergo cleavage in the presence of MeONa.
ChemInform Abstract: Synthesis of N‐Aryl‐1,5,3‐dithiazepanes and N‐Aryl‐1,5,3‐dithiazocanes in the Presence of Samarium‐ and Cobalt‐Containing Catalysts.
Authors: Murzakova N. N. , Prokof'ev K. I. , Tyumkina T. V. , Ibragimov A. G.
Published: September 2012

Efficient procedures for the synthesis of the title compounds (IV) are developed using cyclocondensation as well as by transamination processes.
ChemInform Abstract: DAST Mediated Preparation of β‐Fluoro‐α‐aminophosphonates.
Authors: Kazmierczak Marcin , Koroniak Henryk
Published: September 2012

A new and convenient route to β‐fluoro‐α‐aminophosphonates (IV) using diethylaminosulfur trifluoride for nucleophilic fluorination is described.
ChemInform Abstract: Synthesis of the Antitrypanosomal Agent (.+‐.)‐Hydroxyanthecotulide by Cr(II)‐Catalyzed Allylation and Meyer—Schuster Rearrangement.
Authors: Hodgson David M. , Talbot Eric P. A. , Clark Barry P.
Published: September 2012

A novel strategy for the stereocontrolled synthesis of anti‐ and syn‐hydroxyanthecotulide is presented.
ChemInform Abstract: Lewis Acids as α‐Directing Additives in Glycosylations by Using 2,3‐O‐Carbonate‐Protected Glucose and Galactose Thioglycoside Donors Based on Preactivation Protocol.
Authors: Geng Yiqun , Qin Qi , Ye Xin‐Shan
Published: September 2012

It is found that the carbohydrates can undergo highly α‐selective glycosylations in the presence of BF3 or SnCl4.
ChemInform Abstract: Nanoscale and Nano‐Structured Electrodes of Solid Oxide Fuel Cells by Infiltration: Advances and Challenges
Authors: Jiang San Ping
Published: September 2012

Review: 162 refs.
ChemInform Abstract: The Challenge of Storage in the Hydrogen Energy Cycle: Nanostructured Hydrides as a Potential Solution
Authors: Hanlon James M. , Reardon Hazel , Tapia‐Ruiz Nuria , Gregory Duncan H.
Published: September 2012

Review: 124 refs.
ChemInform Abstract: Synthesis of Highly13C Enriched Carotenoids: Access to Carotenoids Enriched with 13C at Any Position and Combination of Positions
Authors: Lugtenburg Johan , Dawadi Prativa B. S.
Published: September 2012

Review: 28 refs.
ChemInform Abstract: Formation of Five‐ and Six‐Membered Heterocyclic Rings under Radical Cyclization Conditions
Authors: Majumdar K. C. , Karunakar Galla V. , Sinha Biswajit
Published: September 2012

Review: ca. 150 refs.
ChemInform Abstract: Asymmetric Aldol Reactions of Heterocyclic Dienolsilanes and α,β‐Unsaturated Carbonyl Derived Dienolsilanes
Authors: Miao Zhenyuan , Chen Fener
Published: September 2012

Review: 31 refs.
ChemInform Abstract: Molecular Metal Oxide Cluster‐Surface Modified Titanium(IV) Dioxide Photocatalysts.
Authors: Nolan Michael , Iwaszuk Anna , Tada Hiroaki
Published: September 2012

Review: 49 refs.
ChemInform Abstract: Biofilms and Their Engineered Counterparts: A New Generation of Immobilized Biocatalysts
Authors: Winn Michael , Foulkes Joanne M. , Perni Stefano , Simmons Mark J. H. , Overton Tim W. , Goss Rebecca J. M.
Published: September 2012

Review: 41 refs.
ChemInform Abstract: Artificial Chirogenesis: A Gateway to New Opportunities in Material Science and Catalysis
Authors: Escarcega‐Bobadilla Martha V. , Kleij Arjan W.
Published: September 2012

Review: ca. 60 refs.
ChemInform Abstract: Efficient Phosphorescent Polymer Light‐Emitting Diodes by Suppressing Triplet Energy Back Transfer
Authors: Gong Shaolong , Yang Chuluo , Qin Jingui
Published: September 2012

Review: 57 refs.
ChemInform Abstract: Homonuclear Dipolar Recoupling in Solid‐State NMR
Authors: Tycko Robert
Published: September 2012

Review: 38 refs.
Arene–RuII Complexes of Curcumin Exert Antitumor Activity via Proteasome Inhibition and Apoptosis Induction
Authors: Bonfili Laura , Pettinari Riccardo , Cuccioloni Massimiliano , Cecarini Valentina , Mozzicafreddo Matteo , Angeletti Mauro , Lupidi Giulio , Marchetti Fabio , Pettinari Claudio , Eleuteri Anna Maria
Published: September 2012

Organometallic ruthenium(II) complexes of general formula [(η6‐arene)Ru(curcuminato)Cl], with arene being p‐iPrC6H4Me (1), C6H6 (2), and C6Me6 (3), were synthesized, characterized, and evaluated for their antitumor effects. Specifically, we explored their ability to regulate the proteasome, a validated pharmacological target in cancer treatment. Ruthenium complexes inhibited isolated proteasomes to various extents, with the biological activity of these complexes depending on the nature of the bound arene; in particular, [(η6‐arene)Ru(curcuminato)Cl] 2 suppressed proteasomal activities more potently than 1, 3, or free curcumin. Each complex also inhibited proteasomes in cultured colon cancer cells and consequently triggered apoptosis, with the [(η6‐benzene)Ru(curcuminato)Cl] complex 2 being the most active. The influence on the oxidative status of HCT116 cells and the DNA binding ability of the [(η6‐arene)Ru(curcuminato)Cl] complexes were studied. Complex 2 showed the highest antioxidant capacity; moreover, complexes 1 and 2 were shown to bind isolated DNA with higher affinity (up to threefold) than free curcumin. Collectively, our results demonstrate that the complexation of curcumin with ruthenium(II) is a promising starting point for the development of curcumin‐based anticancer drugs.
Highly Reproducible Surface‐Enhanced Raman Spectra on Semiconductor SnO2 Octahedral Nanoparticles
Authors: Jiang Li , Yin Penggang , You Tingting , Wang Hua , Lang Xiufeng , Guo Lin , Yang Shihe
Published: September 2012

Highly reproducible surface‐enhanced Raman scattering (SERS) spectra are obtained on the surface of SnO2 octahedral nanoparticles. The spot‐to‐spot SERS signals show a relative standard deviation (RSD) consistently below 20 % in the intensity of the main Raman peaks of 4‐mercaptobenzoic acid (4‐MBA) and 4‐nitrobenzenethiol (4‐NBT), indicating good spatial uniformity and reproducibility. The SERS signals are believed to mainly originate from a charge‐transfer (CT) mechanism. Time‐dependent density functional theory (TD‐DFT) is used to simulate the SERS spectrum and interpret the chemical enhancement mechanism in the experiment. The research extends the application of SERS and also establishes a new uniform SERS substrate.
Microstructure and molecular microbiology of rapidly formed hydrogen‐ and methane‐producing granules in a phase‐separated anaerobic environment
Authors: Siddiqui Zuhaib , Horan Nigel , Salter Michael
Published: September 2012

Hydrogen and methane were simultaneously produced in a two‐phase reactor, operated to separate the reactions of hydrogen and methanogen production. Each reactor was inoculated with a seed enriched with different microbial consortia. The first phase was operated with a hydraulic retention time of 7 days and at an organic loading rate of 7.7 g VS L−1 d−1 that produced a stable pH of 5.5. This suppressed the growth of methanogens and as a result, the off gas contained up to 27% hydrogen. The second phase was operated with a hydraulic retention time of 12 days and at an organic loading rate of 3.6 g VS L−1 d−1. This permitted the growth of hydrogenotrophs and methanogens to produce methane at a concentration of 60%. Examination of the microbial population of the two reactors both microscopically and using PCR, showed an effective separation of hydrogen‐ and methane‐producing microbial communities. The study revealed that the suppression of hydrogentrophs and methanogens can be achieved by adopting rapid method that leads the growth of hydrogen‐ and methane‐producing granules in phase‐separated anaerobic environment.
Organic contaminants of emerging concern in sediments and flatfish collected near outfalls discharging treated wastewater effluent to the Southern California Bight
Authors: Maruya Keith A. , Vidal-Dorsch Doris E. , Bay Steven M. , Kwon Jeong W. , Xia Kang , Armbrust Kevin L.
Published: September 2012

To investigate the occurrence and bioaccumulation of organic contaminants of emerging concern (CECs) near four major wastewater ocean outfalls in the Southern California Bight, more than 75 pharmaceutical and personal care products, current-use pesticides, and industrial/commercial chemicals were analyzed in sediment and liver tissues of hornyhead turbot (Pleuronichthys verticalis) using gas and liquid chromatography–mass spectrometry. Although most CECs targeted were infrequently detected or not detectable, triclosan, 4-nonylphenol (4-NP) and bis(2-ethylhexylphthalate) were detected in all sediments at median (maximum) concentrations of 5.1 (8.6), 30 (380), and 121 (470) µg/kg, respectively. In the liver, 4-NP and polybrominated diphenyl ether (PBDE) congeners 47 and 99 were detected in >90% of samples at median (maximum) concentrations of 85 (290) and 210 (480) µg/kg, respectively. The sedative diazepam was detected in all liver samples, but was infrequently detected in sediments. Sediment and liver concentrations across outfall locations ranged over several orders of magnitude and were elevated relative to a reference site. Relative to sediment, accumulation in liver of PBDEs 47 and 99 was comparable to that for legacy organochlorines, confirming their high bioaccumulation potential and suggesting their inclusion in future tissue monitoring studies. Mean tissue PBDE and diazepam concentrations were higher in livers from male versus female P. verticalis, suggesting that gender differences also be considered in designing such studies. Environ. Toxicol. Chem. 2012; 31: 2683–2688. © 2012 SETAC
Annual and seasonal evaluation of reproductive status in hornyhead turbot at municipal wastewater outfalls in the Southern California Bight
Authors: Forsgren Kristy L. , Bay Steven M. , Vidal-Dorsch Doris E. , Deng Xin , Lu Guanghua , Armstrong Jeff , Gully Joseph R. , Schlenk Daniel
Published: September 2012

Treated wastewater effluent containing endocrine-disrupting chemicals is discharged into the coastal waters of the Southern California Bight (SCB) daily. The present study investigated changes in indicators of reproductive health and environmental estrogen exposure in hornyhead turbot (Pleuronichthys verticalis) near wastewater outfalls. Fish were collected from discharge areas, farfield stations, and a reference location in the SCB to examine spatial and temporal patterns. Fish from the Orange County outfall farfield site were younger and less sexually mature than fish from other sites. The sex ratio was skewed in some fish from outfall sites as well as from the Dana Point reference site. However, no consistent pattern in sex ratio was present over time. Low-level induction of vitellogenin was frequently observed in male fish from all sites, suggesting widespread exposure to estrogenic compounds, but did not appear to impact reproductive function as there was no incidence of gonad abnormalities (ova-testis). Analysis of historical hornyhead turbot trawl data indicated that populations are either increasing or stable in the SCB; thus, environmental estrogen exposure was not adversely impacting fish abundance. Additional research is needed to determine the cause of the estrogenic response in hornyhead turbot and whether the source of the estrogenic compounds is a consequence of historical contamination or of ongoing sources or representative of baseline characteristic of this species. Environ. Toxicol. Chem. 2012; 31: 2701–2710. © 2012 SETAC
Effect of chronic exposure to zinc in young spats of the Pacific oyster (Crassostrea gigas)
Authors: Devos Alexandre , Voiseux Claire , Caplat Christelle , Fievet Bruno
Published: September 2012

The marine coastal environment is exposed to a mixture of environmental pollutants of anthropogenic origin, resulting in chronic low concentrations of contaminants. As a consequence, most coastal marine species are exposed to low doses of such pollutants during their entire life. Many marine species live for years in their natural environment, whereas they do not under laboratory exposure conditions. Using early stages of development in laboratory work allows animals to be chronically exposed from an early age over a reasonable experiment period. In the present study, the authors investigated the effect of chronic exposure to zinc in spats of the Pacific oyster (Crassostrea gigas), from metamorphosis up to 10 weeks. The authors investigated integrated biological endpoints that would account for the apparent general health of the animals as well as molecular markers showing more subtle effects that could potentially go unnoticed at a biologically integrated level. The authors measured in parallel both growth and the transcriptional level of target stress genes. Growth was monitored by image analysis of large samples to avoid high variability and ensure statistical robustness. A dose–response relationship was derived from growth data, yielding a median effective concentration (EC50) of 7.55 µM. Stress genes selected on the basis of available RNA sequences in C. gigas included genes involved in chaperone proteins, oxidative stress, detoxification, and cell cycle regulation. Out of nine stress target genes, only metallothionein displayed overexpression in response to high levels of zinc. Environ. Toxicol. Chem. 2012; 31: 2841–2847. © 2012 SETAC
Quantifying the effect of nanoparticles on As(V) ecotoxicity exemplified by nano-Fe2O3 (magnetic) and nano-Al2O3
Authors: Hu Ji , Wang Demin , Forthaus Brett E. , Wang Jianmin
Published: September 2012

Nano-Fe2O3 (magnetic) and nano-Al2O3 are increasingly used in biomedical fields for cellular labeling and drug delivery, and in the industry as catalysts. However, they may also serve as carriers of toxic contaminants and negatively impact the environment and human health. In the present study, Ceriodaphnia dubia was used to assess the toxicity of these nanoparticles (NPs) with and without the presence of background arsenic(V) (As[V]). The results showed that although these NPs alone did not exhibit significant toxicity in the experimental concentration range, they could significantly enhance the toxicity of As(V). The accumulation of As(V) on nano-Fe2O3 (m) and nano-Al2O3, as well as the uptake of these NPs in C. dubia, were verified. An inverse relationship between the median lethal concentration (LC50) of the soluble As(V) and the accumulation of NPs in C. dubia was developed. Therefore, the uptake of As(V)-loaded NPs in C. dubia played a key role in enhancing As(V) toxicity. Environ. Toxicol. Chem. 2012; 31: 2870–2876. © 2012 SETAC
An approach for calculating a confidence interval from a single aquatic sample for monitoring hydrophobic organic contaminants
Authors: Matzke Melissa M. , Allan Sarah E. , Anderson Kim A. , Waters Katrina M.
Published: September 2012

The use of passive sampling devices (PSDs) for monitoring hydrophobic organic contaminants in aquatic environments can entail logistical constraints that often limit a comprehensive statistical sampling plan, thus resulting in a restricted number of samples. The present study demonstrates an approach for using the results of a pilot study designed to estimate sampling variability, which in turn can be used as variance estimates for confidence intervals for future n = 1 PSD samples of the same aquatic system. Sets of three to five PSDs were deployed in the Portland Harbor Superfund site for three sampling periods over the course of two years. The PSD filters were extracted and, as a composite sample, analyzed for 33 polycyclic aromatic hydrocarbon compounds. The between-sample and within-sample variances were calculated to characterize sources of variability in the environment and sampling methodology. A method for calculating a statistically reliable and defensible confidence interval for the mean of a single aquatic passive sampler observation (i.e., n = 1) using an estimate of sample variance derived from a pilot study is presented. Coverage probabilities are explored over a range of variance values using a Monte Carlo simulation. Environ. Toxicol. Chem. 2012; 31: 2888–2892. © 2012 SETAC
Prognostic biomarkers of survival in oropharyngeal squamous cell carcinoma: Systematic review and meta‐analysis
Authors: Rainsbury James W. , Ahmed Waseem , Williams Hazel K. , Roberts Sally , Paleri Vinidh , Mehanna Hisham
Published: September 2012

Background

Human papillomavirus (HPV) positivity improves prognosis in patients with oropharyngeal squamous cell carcinoma (OPSCC). Combining HPV status with other biomarkers may improve its prognostic power.

Methods

The approach was a literature search for longitudinal studies of biomarkers in OPSCC, with systematic review and meta‐analysis.

Results

In all, 3130 articles were identified; 32 satisfied the inclusion and exclusion criteria. On meta‐analysis, there was a significant overall survival (OS) benefit for patients with HPV positive and p16 positive tumors. There was some evidence of improved OS of OPSCC patients with raised bcl2; amplification of 11q3 and loss of 16q genes; and low c‐met, ki67, IMD, PLK, FHIT, nuclear surviving, or nuclear cyclin D1. However, none of these was suitable for meta‐analysis.

Conclusion

Survival from OPSCC is associated with several biomarkers, which constitute potential targets for research into improving the prognostic power of HPV in OPSCC. Larger trials are needed, with standardization of cut‐points and adherence to consensus reporting guidelines. © 2012 Wiley Periodicals, Inc. Head Neck, 2013
On the role of soil moisture in daytime evolution of temperatures
Authors: Lockart Natalie , Kavetski Dmitri , Franks Stewart W.
Published: September 2012

This paper explores the relationship between temperature, evaporation and soil moisture using a planetary boundary layer (PBL) model. It focuses on illustrating and quantifying the effect of soil moisture on the evolution of daytime temperatures. A simple convective PBL model coupled with the Penman–Monteith (PM) equation is used to estimate evapotranspiration. Following calibration and sensitivity analysis, the model was used to simulate the relative impact of dry and wet soil moisture conditions on daytime temperatures by changing the surface resistance parameter in the PM equation. It was found that the maximum temperature that can be reached during a day is constrained by the amount of soil moisture and the available net radiation, confirming previously published results. Higher temperatures can be reached with greater net radiation and dry soil moisture conditions. Copyright © 2012 John Wiley & Sons, Ltd.
Quercetin reduces oxidative damage induced by paraquat via modulating expression of antioxidant genes in A549 cells
Authors: Zerin Tamanna , Kim Yong‐Sik , Hong Sae‐Yong , Song Ho‐Yeon
Published: September 2012

Oxidative injury can occur in the lung through the generation of reactive oxygen species (ROS) via redox cycling owing to intentional or accidental ingestion of paraquat (PQ), a common herbicide. A wide array of phytochemicals has been shown to reduce cellular oxidative damage by modulating cytoprotective genes. Quercetin, a well‐known flavonoid, has been reported to display cytoprotective effects by up‐regulating certain cytoprotective genes. In this context, we investigated the effect of quercetin on PQ‐induced cytotoxicity in alveolar A549 cells, modulation of antioxidant genes, activation of transcription factor‐Nrf2 and its target HO‐1 expression. Quercetin reduced PQ‐induced cytotoxicity in A549 cells that was evaluated by both 3‐(4,5‐dimethylthiazol‐2‐yl)‐2, 5‐diphenyl‐tetrazolium bromide (MTT) and lactate dehydrogenase (LDH) assays. Modulation of antioxidant genes was compared when cells were treated with PQ, quercetin and both using qRT‐PCR. Activation of transcription factor‐Nrf2 and induction of its target gene, HO‐1 was demonstrated by western blot analysis. A remarkable reduction in the ROS level as well as an increase in the total cellular glutathione (GSH) level occurred when PQ‐exposed cells were treated with quercetin. Our findings suggest that quercetin may be used to mitigate or minimize oxidative stress via reducing the generation of ROS. Copyright © 2012 John Wiley & Sons, Ltd.