bluuebunny/crossref_metadata_2025 huggingface dataset:
“Clinging‐Microdroplet” Patterning Upon High‐Adhesion, Pillar‐Structured Silicon Substrates
Authors: Su Bin , Wang Shutao , Ma Jie , Song Yanlin , Jiang Lei
Published: June 2011

The rapidly increasing research interest in nanodevices, including nanoelectronics, nano‐optoelectronics, and sensing, requires the development of surface‐patterning techniques to obtain large‐scale arrays of nanounits (mostly nanocrystals and/or nanoparticles) on a silicon substrate. Herein, we demonstrate a “clinging‐microdroplet” method to fabricate patterning crystal arrays based on the employment of high‐adhesion, superhydrophobic, pillar‐structured silicon substrates. Different from the previous hydrophilic/hydrophobic patterned self‐assembly monolayer technique, this method provides a novel strategy to fabricate patterning crystal arrays upon pillar‐structured silicon substrates of homogenous superhydrophobicity and high adhesion, which greatly simplifies the modification process of the supporting substrates. Ordered crystal arrays with a tunable size and distribution density were successfully generated, and individual crystals grew on the top of each micropillar. Besides soluble inorganic materials, protein microspheres and suspending Ag‐nanoparticle or polystyrene‐microsphere aggregations could also be patterned in regular arrays, showing the wide adaptation of such an adhesive patterning technique. This novel and low‐cost technique for patterning crystal arrays upon silicon substrates could yield breakthroughs in areas ranging from nanodevices to nanoelectronics.
ZrOCl2·8H2O as a highly efficient, eco‐friendly and recyclable Lewis acid catalyst for one‐pot synthesis of N‐substituted pyrroles under solvent‐free conditions at room temperature
Authors: Rahmatpour Ali
Published: June 2011

A new and efficient method for the synthesis of a variety of N‐substituted pyrroles from condensation reactions of 2,5‐hexanedione with amines or diamines using ZrOCl2·8H2O as a water‐tolerant Lewis acid catalyst at room temperature is described.The use of nontoxic, inexpensive, easily available and reusable catalyst under solvent‐free conditions make this protocol practical, environmentally friendly and economically attractive. Copyright © 2011 John Wiley & Sons, Ltd.
Suzuki cross‐coupling reactions of aryl chlorides using [Cl2Pd(COD)]/piperazine derivative under microwave conditions
Authors: Zhou Zhong‐Gao , Shi Ji‐Cheng , Hu Qiao‐Sheng , Xie Yong‐Rong , Du Zi‐Yi , Zhang Shi‐Yong
Published: June 2011

A new strategy to significantly improve the efficiency of Suzuki reactions was achieved under microwave irradiation. [Cl2Pd(COD)]/piperazine derivative 1 catalyzed aryl chlorides with phenylboronic acid in methanol (50%) affording excellent yields under aerobic conditions. Application of this strategy to the synthesis of liquid crystal material is also described. Copyright © 2011 John Wiley & Sons, Ltd.
Prejudice and the Unexamined Life: A Neuro‐psychoanalytic Framework for the Repressed Conflict between Ethnic and National Identities among Arab‐Jews in Israel
Authors: Cohen Shuki J.
Published: June 2011

This article proposes a framework for understanding the processes involved in politically‐motivated memory and identity formation. Specifically, it examines how these processes respond to both explicit and implicit politico‐social motivations to suppress certain parts of them while augmenting others. The proposed framework draws from emerging commonalities between neuro‐cognitive and psychoanalytic theories, and conceptualizes both internal and external prejudice as motivated cognitive‐emotional phenomena in and of themselves, devoid of politically‐motivated cognitive biases or prejudice. Using autobiographical, biographical and scholarly sources, I examine the motivated dissociation between the avowed and disavowed aspects of the conflicted Arab identity among Arab‐Jews in Israel is examined. Following psychoanalytic theory, the proposed framework may explain not only the internal conflict within the Iraqi‐Jewish community, but also the vehement support for anti‐Arab political sentiments within the larger Arab‐Jewish community in Israel (known more by the euphemism ‘Sephardi Jews’) – as ordained by the hegemonic Ashkenazi Zionist elite of Israel for the past 100 years. This article then traces evidence for the ‘return of the repressed’ among a growing number of contemporary Israeli Jews of Arab descent, who seem increasingly aware of the limited ability of the Zionist ‘melting pot’ ideology to adequately represent their identity. Based on the proposed framework, this article advocates for the impartial exploration of the disavowed Arab identity among Israeli Jews as a potential source of reducing pathogenic anti‐Arab prejudice and promoting greater humanism in the Israeli‐Palestinian conflict. Copyright © 2011 John Wiley & Sons, Ltd.
A Self‐Complementary Nucleoside: Synthesis, Solid‐State Structure, and Fluorescence Behavior
Authors: Bang Eun‐Kyoung , Won Jiyeon , Moon Dohyun , Lee Jin Yong , Kim Byeang Hyean
Published: June 2011

A novel self‐complementary nucleoside (AT), featuring two complementary nucleobases linked through an ethynyl group has been synthesized. The rigid aromatic nucleobases provided AT with a pale‐blue fluorescence. Unlike most fluorescent organic molecules, nucleoside AT gives enhanced fluorescence in solid state. It exhibits considerably enhanced fluorescence intensity and a remarkable redshift (ca. 70 nm) in its emission maximum upon an increase in concentration or decrease in temperature as a result of the formation of aggregates stabilized through hydrogen bonding and π–π stacking of well‐organized AT assemblies; these interactions are also evident in the solid‐state structure, determined by X‐ray crystallography. DFT calculations supported the preference of such aggregation processes.
Are viruses a source of new protein folds for organisms? – Virosphere structure space and evolution
Authors: Abroi Aare , Gough Julian
Published: June 2011

A crucially important part of the biosphere – the virosphere – is too often overlooked. Inclusion of the virosphere into the global picture of protein structure space reveals that 63 protein domain superfamilies in viruses do not have any structural and evolutionary relatives in modern cellular organisms. More than half of these have functions which are not virus‐specific and thus might be a source of new folds and functions for cellular life. The number of viruses on the planet exceeds that of cells by an order of magnitude and viruses evolve up to six orders of magnitude faster. As a result, cellular species are subject to a constitutive ‘flow‐through’ of new viral genetic material. Due to this and the relaxed evolutionary constraints in viruses, the transfer of domains between host‐to‐virus could be a mechanism for accelerated protein evolution. The virosphere could be an engine for the genesis of protein structures, and may even have been so before the last universal common ancestor of cellular life.
Polymorphisms in the toll-like receptor 9 gene associated with sepsis and multiple organ dysfunction after major blunt trauma
Authors: Chen K-H , Zeng L , Gu W , Zhou J , Du D-Y , Jiang J-X
Published: June 2011

Background

Toll-like receptor (TLR) 9 is the pattern recognition receptor for microbial DNA. Genetic variation within pattern recognition receptors for bacterial endotoxin and exotoxin has been shown to be associated with the risk of sepsis and organ dysfunction in critical illness. However, little is known about the clinical relevance of TLR9 gene polymorphisms in critical illness.

Methods

A total of 557 patients with major blunt trauma were included in the study. Genetic variation data for the entire TLR9 gene were obtained from the HapMap Project. The genotypes of TLR9 gene polymorphisms were determined using a pyrosequencing method. Whole peripheral blood samples obtained immediately after admission were stimulated with bacterial DNA and production of tumour necrosis factor (TNF) α was then determined. Sepsis morbidity rate and multiple organ dysfunction (MOD) scores were assessed.

Results

Of five single-nucleotide polymorphisms (SNPs) genotyped, four (rs187084, rs352139, rs352140 and rs352162) existed as common SNPs and were in strong linkage disequilibrium. Both rs187084 and rs352162 were significantly associated with TNF-α production by peripheral blood leucocytes in response to bacterial DNA stimulation and a higher sepsis morbidity rate in patients with major trauma. In addition, the rs352162 polymorphism was significantly associated with MOD scores, whereas rs187084 showed a trend to be associated with MOD score.

Conclusion

TLR9 polymorphisms rs187084 and rs352162 might be used to provide relevant risk estimates for the development of sepsis and MOD in patients with major trauma.
Five-year results of a randomized clinical trial comparing endovenous laser ablation with cryostripping for great saphenous varicose veins
Authors: Disselhoff B C V M , der Kinderen D J , Kelder J C , Moll F L
Published: June 2011

Background

This was the long-term follow-up of a previously reported randomized clinical trial comparing endovenous laser ablation (EVLA) with cryostripping for great saphenous varicose veins.

Methods

A total of 120 patients with great saphenous varicose veins were randomized 1:1 to EVLA or cryostripping. Principal outcome measures were freedom from incompetence or neovascularization on duplex imaging, and improvement in Venous Clinical Severity Score (VCSS) and Aberdeen Varicose Vein Severity Score (AVVSS) 5 years after treatment.

Results

Life-table analysis showed freedom from duplex-derived incompetence and neovascularization at 5 years in 62 (95 per cent confidence interval 50 to 76) per cent after EVLA and in 51 (39 to 66) per cent after cryostripping (P = 0·246). Neovascularization was more common after cryostripping, but incompetent tributaries were more common after EVLA. VCSS and AVVSS values improved significantly after treatment in both groups, and were maintained for 5 years, but with no significant difference between the groups.

Conclusion

In this study, no significant difference was demonstrated in late outcome after EVLA or cryostripping in patients with great saphenous varicose veins. Registration number: ISRCTN33832691 (http://www.controlled-trials.com).
Hydride Mobility in Trinuclear Sulfido Clusters with the Core [Rh3(μ‐H)(μ3‐S)2]: Molecular Models for Hydrogen Migration on Metal Sulfide Hydrotreating Catalysts
Authors: Jiménez M. Victoria , Lahoz Fernando J. , Lukešová Lenka , Miranda José R. , Modrego Francisco J. , Nguyen Duc H. , Oro Luis A. , Pérez‐Torrente Jesús J.
Published: June 2011

The treatment of [{Rh(μ‐SH){P(OPh)3}2}2] with [{M(μ‐Cl)(diolef)}2] (diolef=diolefin) in the presence of NEt3 affords the hydrido–sulfido clusters [Rh3(μ‐H)(μ3‐S)2(diolef){P(OPh)3}4] (diolef=1,5‐cyclooctadiene (cod) for 1, 2,5‐norbornadiene (nbd) for 2, and tetrafluorobenzo[5,6]bicyclo[2.2.2]octa‐2,5,7‐triene (tfb) for 3) and [Rh2Ir(μ‐H)(μ3‐S)2(cod){P(OPh)3}4] (4). Cluster 1 can be also obtained by treating [{Rh(μ‐SH){P(OPh)3}2}2] with [{Rh(μ‐OMe)(cod)}2], although the main product of the reaction with [{Ir(μ‐OMe)(cod)}2] was [RhIr2(μ‐H)(μ3‐S)2(cod)2{P(OPh)3}2] (5). The molecular structures of clusters 1 and 4 have been determined by X‐ray diffraction methods. The deprotonation of a hydrosulfido ligand in [{Rh(μ‐SH)(CO)(PPh3)}2] by [M(acac)(diolef)] (acac=acetylacetonate) results in the formation of hydrido–sulfido clusters [Rh3(μ‐H)(μ3‐S)2(CO)2(diolef)(PPh3)2] (diolef=cod for 6, nbd for 7) and [Rh2Ir(μ‐H)(μ3‐S)2(CO)2(cod)(PPh3)2] (8). Clusters 1–3 and 5 exist in solution as two interconverting isomers with the bridging hydride ligand at different edges. Cluster 8 exists as three isomers that arise from the disposition of the PPh3 ligands in the cluster (cis and trans) and the location of the hydride ligand. The dynamic behaviour of clusters with bulky triphenylphosphite ligands, which involves hydrogen migration from rhodium to sulfur with a switch from hydride to proton character, is significant to understand hydrogen diffusion on the surface of metal sulfide hydrotreating catalysts.
Two Cu21 Clusters with Pseudo‐D3 Symmetry Derived from the D‐Saccharate Pentaanion, C6H5O85−
Authors: Abrahams Brendan F. , McCormick Laura J. , Moubaraki Boujemaa , Murray Keith S. , Robson Richard , Waters Tom
Published: June 2011

The combination of Cu(NO3)2, potassium hydrogen saccharate (KC6H9O8) and 1,10‐phenanthroline (phen) yields a pair of chiral cluster compounds, each with composition Cu21(C6H5O8)6(phen)12(NO3)12⋅solvate. One of the compounds forms as orthorhombic crystals, while the other forms cubic crystals. Each of the clusters has D3 or approximate D3 symmetry, but the arrangement of the saccharate ion in the clusters is quite different in the two cases. The clusters in the cubic form interact with neighbouring clusters through face‐to‐face π interactions involving the phen ligands, an association that leads to the generation of very large solvent‐filled spaces in the crystal structure. In contrast the clusters in the orthorhombic form are much more densely packed. At the centre of each cluster that crystallises in the orthorhombic form is a nitrate anion that binds to six CuII centres. ESI mass spectral studies indicate that the Cu21 clusters exist in solution. Solid‐state magnetic studies of the cubic form of Cu21 show that antiferromagnetic coupling occurs to leave a non‐zero‐spin ground state, and comparisons are made to the magnetic data for other large CuII clusters.
Design, Synthesis, ADME Properties, and Pharmacological Activities of β‐Alanyl‐D‐histidine (D‐Carnosine) Prodrugs with Improved Bioavailability
Authors: Orioli Marica , Vistoli Giulio , Regazzoni Luca , Pedretti Alessandro , Lapolla Annunziata , Rossoni Giuseppe , Canevotti Renato , Gamberoni Luca , Previtali Massimo , Carini Marina , Aldini Giancarlo
Published: June 2011

β‐Alanyl‐D‐histidine (D‐CAR, the enantiomer of the natural dipeptide carnosine) is a selective and potent sequestering agent of reactive carbonyl species (RCS) that is stable against carnosinase, but is poorly absorbed in the gastrointestinal tract. Herein we report a drug discovery approach aimed at increasing the oral bioavailability of D‐CAR. In our study we designed, synthesized, and evaluated a series of novel lipophilic D‐CAR prodrugs. The considered prodrugs can be divided into two categories: 1) derivatives with both terminal groups modified, in which the carboxyl terminus is always esterified while the amino terminus is protected by an amidic (N‐acetyl derivatives) or a carbamate (ethyloxy or benzyloxy derivatives) function; 2) derivatives with only one terminus modified, which can be alkyl esters as well as amidic or carbamate derivatives. The prodrugs were designed considering their expected lipophilicity and their hydrolysis predicted by docking simulations on the most important human carboxylesterase (hCES1). The stability and metabolic profile of the prodrugs were studied by incubating them with rat and human serum and liver fractions. The octyl ester of D‐CAR (compound 13) was chosen as a candidate for further pharmacological studies due to its rapid hydrolysis to the bioactive metabolite in vitro. Pharmacokinetic studies in rats confirmed the in vitro data and demonstrated that the oral bioavailability of D‐CAR is increased 2.6‐fold if given as an octyl ester relative to D‐CAR. Compound 13 was then found to dose‐dependently (at daily doses of 3 and 30 mg kg−1 equivalent of D‐CAR) decrease the development of hypertension and dyslipidemia, to restore renal functions of Zucker fa/fa obese rats, and to inhibit the carbonylation process (AGEs and pentosidine) as well as oxidative stress (urinary 8‐epi‐prostaglandin F2α and nitrotyrosine). A plausible mechanism underlying the protective effects of 13 is RCS sequestration, as evidenced by the significant increase in the level of adduct between CAR and 4‐hydroxy‐trans‐2‐nonenal (HNE, the main RCS generated by lipid oxidation) in the urine of treated animals.
Alternating‐Current Measurements in Scanning Electrochemical Microscopy, Part 1: Principle and Theory
Authors: Trinh Dao , Keddam Michel , Novoa Xosé R. , Vivier Vincent
Published: June 2011

The development of the scanning electrochemical microscope in ac mode is presented from both experimental and theoretical point of views. The experiments are performed with the ferri/ferrocyanide redox mediator as model system. Based on analysis of the frequency‐dependent collection efficiency, diffusion between the probe and the substrate is investigated, and analysis of time constants allows evaluation of the size of the sensing area under investigation. The experimental results are in good agreement with numerical simulations.
Catalytic Production of Conjugated Fatty Acids and Oils
Authors: Philippaerts An , Goossens Steven , Jacobs Pierre A. , Sels Bert F.
Published: June 2011

The reactive double bonds in conjugated vegetable oils are of high interest in industry. Traditionally, conjugated vegetable oils are added to paints, varnishes, and inks to improve their drying properties, while recently there is an increased interest in their use in the production of bioplastics. Besides the industrial applications, also food manufactures are interested in conjugated vegetable oils due to their various positive health effects. While the isomer type is less important for their industrial purposes, the beneficial health effects are mainly associated with the c9,t11, t10,c12 and t9,t11 CLA isomers. The production of CLA‐enriched oils as additives in functional foods thus requires a high CLA isomer selectivity. Currently, CLAs are produced by conjugation of oils high in linoleic acid, for example soybean and safflower oil, using homogeneous bases. Although high CLA productivities and very high isomer selectivities are obtained, this process faces many ecological drawbacks. Moreover, CLA‐enriched oils can not be produced directly with the homogeneous bases. Literature reports describe many catalytic processes to conjugate linoleic acid, linoleic acid methyl ester, and vegetable oils rich in linoleic acid: biocatalysts, for example enzymes and cells; metal catalysts, for example homogeneous metal complexes and heterogeneous catalysts; and photocatalysts. This Review discusses state‐of‐the‐art catalytic processes in comparison with some new catalytic production routes. For each category of catalytic process, the CLA productivities and the CLA isomer selectivity are compared. Heterogeneous catalysis seems the most attractive approach for CLA production due to its easy recovery process, provided that the competing hydrogenation reaction is limited and the CLA production rate competes with the current homogeneous base catalysis. The most important criteria to obtain high CLA productivity and isomer selectivity are (1) absence of a hydrogen donor, (2) absence of catalyst acidity, (3) high metal dispersion, and (4) highly accessible pore architecture.
Genome‐wide association studies (GWAS): impact on elucidating the aetiology of diabetes
Authors: Hakonarson Hakon , Grant Struan F. A.
Published: June 2011

It has proven to be challenging to isolate the genes underlying the genetic components conferring susceptibility to type 1 and type 2 diabetes. Unlike previous approaches, ‘genome‐wide association studies’ have extensively delivered on the promise of uncovering genetic determinants of complex diseases, with a number of novel disease‐associated variants being largely replicated by independent groups. This review provides an overview of these recent breakthroughs in the context of type 1 and type 2 diabetes, and outlines strategies on how these findings will be applied to impact clinical care for these two highly prevalent disorders. Copyright © 2011 John Wiley & Sons, Ltd.
Early viral replication in lymph nodes provides HIV with a means by which to escape NK‐cell‐mediated control
Authors: Luteijn Rutger , Sciaranghella Gaia , van Lunzen Jan , Nolting Anne , Dugast Anne‐Sophie , Ghebremichael Musie S. , Altfeld Marcus , Alter Galit
Published: June 2011

Acute HIV infection is marked by dramatic viral replication associated with preferential replication within secondary lymphoid tissues, such as lymph nodes (LNs), that is rapidly but incompletely contained to a viral setpoint. Accumulating evidence supports a role for natural killer (NK) cells in the early control of HIV infection; however, little is known about the location of their antiviral control. Given that HIV replicates profusely in LNs during early infection, we sought to define whether changes occurred in the NK cell infiltrate within these sites during the first year of HIV infection. Surprisingly, NK cell numbers and distribution were unaltered during early HIV infection. LN NK cells expressed decreased inhibitory receptors, were more highly activated, and expressed elevated TRAIL, potentially conferring a superior capacity for NK cells to become activated and control infection. Most noticeably, KIR+ NK cells were rarely detected in the LN during HIV infection, associated with diminished migratory capacity in the setting of reduced expression of CX3CR1 and CXCR1. Thus, incomplete control of HIV viral replication during early disease may be due to the inefficient recruitment of KIR+ NK cells to this vulnerable site, providing HIV a niche where it can replicate unabated by early NK‐cell‐mediated innate pressure.
TLR activation enhances C5a‐induced pro‐inflammatory responses by negatively modulating the second C5a receptor, C5L2
Authors: Raby Anne‐Catherine , Holst Benjamin , Davies James , Colmont Chantal , Laumonnier Yves , Coles Barbara , Shah Sanjoy , Hall Judith , Topley Nicholas , Köhl Jörg , Morgan B. Paul , Labéta Mario O.
Published: June 2011

TLR and complement activation ensures efficient clearance of infection. Previous studies documented synergism between TLRs and the receptor for the pro‐inflammatory complement peptide C5a (C5aR/CD88), and regulation of TLR‐induced pro‐inflammatory responses by C5aR, suggesting crosstalk between TLRs and C5aR. However, it is unclear whether and how TLRs modulate C5a‐induced pro‐inflammatory responses. We demonstrate a marked positive modulatory effect of TLR activation on cell sensitivity to C5a in vitro and ex vivo and identify an underlying mechanistic target. Pre‐exposure of PBMCs and whole blood to diverse TLR ligands or bacteria enhanced C5a‐induced pro‐inflammatory responses. This effect was not observed in TLR4 signalling‐deficient mice. TLR‐induced hypersensitivity to C5a did not result from C5aR upregulation or modulation of C5a‐induced Ca2+ mobilization. Rather, TLRs targeted another C5a receptor, C5L2 (acting as a negative modulator of C5aR), by reducing C5L2 activity. TLR‐induced hypersensitivity to C5a was mimicked by blocking C5L2 and was not observed in C5L2KO mice. Furthermore, TLR activation inhibited C5L2 expression upon C5a stimulation. These findings identify a novel pathway of crosstalk within the innate immune system that amplifies innate host defense at the TLR‐complement interface. Unravelling the mutually regulated activities of TLRs and complement may reveal new therapeutic avenues to control inflammation.
ZnII–2,2′:6′,2″‐Terpyridine‐Based Complex as Fluorescent Chemosensor for PPi, AMP and ADP
Authors: Das Priyadip , Ghosh Amrita , Kesharwani Manoj K. , Ramu Vadde , Ganguly Bishwajit , Das Amitava
Published: June 2011

A new ZnII–2,2′:6′,2″‐terpyridine complex, derivatized with a coumarin moiety (L1Zn), acts as a fluorescent chemosensor for different biologically important phosphates like PPi, AMP and ADP in mixed aqueous media. Depending on the proportion of the aqueous fraction present in the solvent mixture, L1Zn shows a preference for different phosphate moieties at physiological pH. In an aqueous acetonitrile (2:3, v/v) medium this reagent shows a preference for AMP as compared to ADP, ATP and PPi. The binding affinities of L1Zn with different phosphate ions and associated shifts in the electronic spectra were rationalized by DFT calculations. Such an example of a receptor that is selective for AMP under physiological conditions is rare in the literature.
Guanidino‐Functionalised Aromatic Electron Donors at Work: Competing Hydrogen‐ and Electron‐Transfer Reactions in the Course of the Synthesis of Gold Acetylide Complexes
Authors: Emeljanenko Dimitri , Kaifer Elisabeth , Himmel Hans‐Jörg
Published: June 2011

In this work reactions between [AuCl(PPh3)] and HC≡CAr (Ar = phenyl, pyridinyl, biphenyl or p‐acetylphenyl) in the presence of the nitrogen base and organic electron donor1,2,4,5‐tetrakis(N,N′‐dimethyl‐N,N′‐ethyleneguanidino)benzene (1) were studied. Two different product types were isolated and characterised: the neutral AuI acetylides[Au(C≡CAr)PPh3] and the salts (1)[Au(C≡CAr)2]2. They can be easily separated from each other by crystallisation under different conditions. The yields strongly depend on the applied acetylene. While the first product type underlines the basic properties of 1, the second product type highlights its electron‐donor capacity. The experimental results indicate reduction of the C−H protons to H2 and two‐electron oxidation of 1. Thermal decomposition of (1)[Au(C≡CAr)2]2 (Ar = Ph) leads back to the neutral guanidine and Au nanoparticles (accompanied by oxidative coupling of the two acetylide ligands).
Tetrahedratic Mesophases, Ambidextrous Chiral Domains and Helical Superstructures Produced by Achiral 1,1′‐Disubstituted Ferrocene Derivatives
Authors: Kim Eun Ho , Kadkin Oleg Nikolaevich , Kim So Yeon , Choi Moon‐Gun
Published: June 2011

A series of symmetrically and asymmetrically 1,1′‐disubstituted mesogenic ferrocene derivatives exhibiting nonconventional lamellar and nematic phases has been synthesized. Liquid‐crystal properties of these compounds were investigated by polarizing optical microscopy (POM), thermal analysis (DSC) and X‐ray scattering methods (XRD). XRD patterns and optical textures of the mesophases have a complex appearance, standing apart from the signatures of previously classified liquid crystals. The most important features of the new mesophases are their spontaneous separation into large macroscopic chiral domains of opposite handednesses, intricate helical and myelinic supramolecular structures and a few signs of possible optical biaxiality. A reasonable explanation of these findings can be drawn from the tetrahedral liquid crystal order. Free rotation of the cyclopentadiene rings in the ferrocene moiety around their normal axis makes viable bent conformations of the rod‐like molecules and further stabilization of the conformational enantiomers through assembly into tetrahedral molecular associates. Thus, fundamentally new types of mesophases arise from such a molecular arrangement. In addition, a nontrivial case of mixed packing of bent and nonbent molecules into columnar mesophases was detected in one of the symmetrically substituted ferrocene derivatives. Basic relationships between mesomorphic properties, supramolecular organization and chemical structures of the ferrocenomesogens have been outlined.
Oxo Boron Clusters and Their Open Frameworks
Authors: Lin Zhi‐En , Yang Guo‐Yu
Published: June 2011

This review article briefly summarizes the recent research advances in the field of crystalline oxo boron clusters and their open frameworks. By using different amine molecules and transition metal complexes or inorganic ions as the charge‐balancing agents, different oxo boron clusters, such as [B3O3(OH)4]–, [B4O5(OH)4]2–, [B5O6(OH)4]–, [B7O9(OH)5]2–, [B8O10(OH)6]2–, [B9O12(OH)6]3–, and [B14O20(OH)6]4– polyanions, have been successfully isolated and structurally characterized. These polyborate anions may act as the main building blocks to create new open‐framework compounds with layered and three‐dimensional structures. Odd ring channels and helical channels are noteworthy in open‐framework borate structures. Besides their traditional zeolitic properties, open‐framework borates exhibit interesting optical properties including photoluminescence and second harmonic generation, suggesting their potential applications in catalysis, nonlinear optics, display and lighting devices.
Catalyst‐Free and Catalysed Addition of P(O)–H Bonds to Allenyl/Alkynyl‐Phosphonates and ‐Phosphane Oxides: Use of a Robust, Recoverable Dinuclear Palladium(I) Catalyst
Authors: Srinivas Venu , Balaraman E. , Sajna K. V. , Kumara Swamy K. C.
Published: June 2011

An effective, recoverable, dinuclear palladium(I) catalyst [(OCH2CMe2CH2O)PSPd(PPh3)]2 has been explored and compared with other traditional palladium catalysts (e.g., [Pd(PPh3)4]) in the phosphonylation/phosphanylation ofallenes (OCH2CMe2CH2O)P(O)CH=C=CH2 (1), Ph2P(O)CH=C=CH2 (2), (EtO)2P(O)CH=C=CH2 (3) (OCH2CMe2CH2O)P(O)CH=C=CMe2 (4), Ph2P(O)CH=C=CMe2 (5), (OCH2CMe2CH2O)P(O)C(Ph)=C=CH2 (6) and Ph2P(O)C(Ph)=C=CH2 (7). The phosphonylation/phosphanylation, in general, occurred at the carbon β to the phosphorus atom, but the concomitant proton addition took place at the α or γ positions leading to either allyl‐ or vinyl‐phosphonates. The use of P(nBu)3 as catalyst led to geminal and bis‐phosphonylation/phosphanylation with less substituted =CH2 terminal allenes 1 and 2. In conjunction with the use of the corresponding isomeric alkynes 8 and 9, as many as five different types of phosphonylated products have been synthesized. The reactions with the more substituted allenes 4–7 gave single products in most cases. Several examples of catalyst‐free, solvent‐free phosphanylation reactions are also described. The reactivity of the phosphonylating/phosphanylating agents was found to be (OCH2CMe2CH2O)P(O)H (10) < (OCH2CMe2CH2O)P(S)H (11) < Ph2P(O)H (12) ≈ Ph2P(S)H (13). The catalytic activity of the recoverable dinuclear palladium(I) complex [(OCH2CMe2CH2O)PSPd(PPh3)]2 (14), which poses interesting questions about the mechanistic pathway, is briefly highlighted. Structures of the dinuclear palladium(I) catalyst 14 and the key products were determined by X‐ray crystallography.
Ruthenium(II)‐Catalyzed Asymmetric Transfer Hydrogenation Using Unsymmetrical Vicinal Diamine‐Based Ligands: Dramatic Substituent Effect on Catalyst Efficiency
Authors: Zhang Bo , Wang Hui , Lin Guo‐Qiang , Xu Ming‐Hua
Published: June 2011

The use of unsymmetrical vicinal diamines as ligands for Ru‐catalyzed asymmetric transfer hydrogenation is described. With a SmI2‐mediated cross‐coupling protocol, a series of enantiomerically pure unsymmetrical vicinal diamines were readily prepared and examined in the asymmetric transfer hydrogenation. It was found that an aromatic substituent on the carbon bearing the –NHTs group and a bulky alkyl substituent on the other side, are both very important for the effectiveness of the ligand, suggesting that the substituent has a dramatic effect on the catalyst efficiency. With ligand 8, excellent enantioselectivities that are comparable to N‐tosyl‐1,2‐diphenylethane‐1,2‐diamine (TsDPEN) were achieved. The results provide some helpful information on the mechanism of Ru‐catalyzed asymmetric transfer hydrogenation.
Site‐Selective Synthesis of Arylated Indenones by Suzuki–Miyaura Cross‐Coupling Reactions of 2,3,5‐Tribromoinden‐1‐one
Authors: Zinad Dhafer Saber , Hussain Munawar , Villinger Alexander , Langer Peter
Published: June 2011

The first transition‐metal‐catalyzed cross‐coupling reactions of 2,3,5‐tribromo‐1H‐inden‐1‐one are reported. The Suzuki–Miyaura reaction of 2,3,5‐tribromo‐1H‐inden‐1‐one with three equivalents of arylboronic acid gave 2,3,5‐triaryl‐1H‐inden‐1‐ones. The reaction with one and two equivalents of arylboronic acid gave 2,5‐dibromo‐3‐aryl‐1H‐inden‐1‐ones and 5‐bromo‐2,3‐diaryl‐1H‐inden‐1‐ones, respectively, with very good site‐selectivity. The one‐pot reaction of 2,3,5‐tribromo‐1H‐inden‐1‐one with one equivalent of two different arylboronic acids afforded 5‐bromo‐2,3‐diaryl‐1H‐inden‐1‐ones containing two different terminal aryl groups. Other one‐pot reactions allowed the synthesis of 2,3,5‐triaryl‐1H‐inden‐1‐ones containing different aryl groups.
Organocatalyzed Aziridination of α‐Branched Enals: Enantioselective Synthesis of Aziridines with a Quaternary Stereo­center
Authors: Desmarchelier Alaric , Pereira de Sant'Ana Danilo , Terrasson Vincent , Campagne Jean Marc , Moreau Xavier , Greck Christine , Marcia de Figueiredo Renata
Published: June 2011

Organocatalytic access to N‐tosylaziridines catalyzed by diarylprolinol trimethylsilyl ether [Ar = 3,5‐(CF3)2C6H3] starting from different α‐substituted‐α,β‐unsaturated aldehydes is described. The products were obtained in good yields (up to 86 %) and enantioselectivities (up to 90 % ee) and could rapidly be transformed under various conditions, including ring opening, to afford useful small molecules possessing not only the aziridine and aldehyde moieties but also other functionalities such as alcohol, acid, ester, or amino alcohol.
Synthesis of Novel Iminosugar‐Based Trehalase Inhibitors by Cross‐Metathesis Reactions
Authors: Bini Davide , Forcella Matilde , Cipolla Laura , Fusi Paola , Matassini Camilla , Cardona Francesca
Published: June 2011

The synthesis of a novel class of trehalase inhibitors composed of iminopyranose or iminofuranose residues linked at the pseudoanomeric carbon through an alkyl chain is described. A set of six novel compounds was prepared by the same reaction sequence involving the Grubbs Ru–carbene‐catalyzed cross‐metathesis (CM) of different N‐Cbz‐protected allyl C‐iminoglycosides as the key step in homo‐ or heterodimerization reactions. The target products, obtained with the CM reaction, were fully hydrogenated by catalytic hydrogenolysis, and preliminary biological screening of the products as inhibitors of commercially available porcine trehalase was performed.
Stereoselective Strecker and Carbamate Annulation Methodology for the Synthesis of 1‐Amino‐1,2,5‐trideoxy‐2,5‐imino‐L‐iditol
Authors: Win‐Mason Anna L. , Dangerfield Emma M. , Tyler Peter C. , Stocker Bridget L. , Timmer Mattie S. M.
Published: June 2011

An efficient and highly stereoselective synthesis of L‐ido‐aminoiminosugar 3 has been described. Key in the synthesis is the application of a diastereoselective Strecker reaction and the extension of our carbamate annulation methodology to protected and functionalized alkenylamines. In addition, the identification of the primary iodide as a key intermediate during the carbamate annulation reaction provides insight into the mechanism of this reaction.
Embarrassment: The ingroup–outgroup audience effect in faux pas situations
Authors: Eller Anja , Koschate Miriam , Gilson Kim‐Michelle
Published: June 2011

Embarrassment arises when we reveal an apparent flaw of the self in front of others, for instance, in a faux pas situation. An audience is crucial for embarrassment, but the group membership of the audience has not yet been studied. According to the social identity approach, we assign more importance to evaluations by ingroup than by outgroup members, particularly when we identify highly, and the outgroup is of lower status. A pilot study (N = 30) showed that embarrassment correlated positively with group membership of the audience and with identification. Studies 1 to 3 presented participants with several faux pas scenarios. In Study 1 (between‐participants design; N = 75), participants reported higher embarrassment in ingroup (Norwegian) and equal‐status outgroup (Swedish) conditions than in a lower‐status outgroup condition (Polish). In Study 2 (within‐participants design; N = 135), participants reported higher embarrassment when they imagined the audience to be other Scots (ingroup) than Americans or Poles (outgroups), particularly when they perceived the outgroup to be lower in status. In Study 3 (between‐participants design; N = 59), high identifiers but not low identifiers showed the expected ingroup–outgroup audience effect. Implications for intergroup relations are discussed. Key Message: Embarrassment following faux pas situations depends on the group membership of the audience, relative status of the audience and ingroup identification. Copyright © 2011 John Wiley & Sons, Ltd.
Tree establishment on bars in low‐order gravel‐bed mountain streams
Authors: Charron Isabelle , Johnson Edward A. , Martin Y. E.
Published: June 2011

In many large alluvial rivers, trees often recruit and survive along laterally accreted sediments on bars. This produces a gradient of tree ages and composition with distance from the active channel. However, in low‐order, gravel‐bed mountain streams, such as the stream investigated in this study, it is suggested that vertical accretion results in sediment deposition patterns on bars that are often highly patchy. Consequently, tree species and ages are also heterogeneously distributed, rather than having distinct linear or arcuate banding patterns with distance from the channel. In addition, overall age patterns of trees on these bars follow the distribution of floods, with numerous young trees and few older trees. Recruitment is fairly continuous on these bars and is not correlated with high water years, suggesting that even flows close to bankfull levels are capable of transporting fine sediment to the bars on which trees establish. This pattern of sediment deposition/erosion and the resulting tree recruitment and survival seem to be a result of valley confinement and the lack of lateral accretion in these smaller, mountainous channels. Copyright © 2011 John Wiley & Sons, Ltd.
Lavender and peppermint essential oils as effective mushroom tyrosinase inhibitors: a basic study
Authors: Fiocco Daniela , Fiorentino Daniela , Frabboni Laura , Benvenuti Stefania , Orlandini Giulia , Pellati Federica , Gallone Anna
Published: June 2011

Screening and characterization of novel tyrosinase inhibitors is useful for applications in food technology, cosmetics and medicine. The hydrodistilled essential oils from lavender Lavandula spica L. and peppermint Mentha x piperita L. were investigated for tyrosinase inhibitory activity. Their composition was assessed by gas chromatography–mass spectrometry. Both oils inhibited mushroom tyrosinase in a dose dependent manner. The IC50 values were estimated, kinetics were analysed and Ki values were determined. Our results indicate that lavender and peppermint essential oils may be promising herbal ingredients for developing depigmenting agents in clinical, cosmetic and industrial processes. Copyright © 2011 John Wiley & Sons, Ltd.
Robust design in aerodynamics using third‐order sensitivity analysis based on discrete adjoint. Application to quasi‐1D flows
Authors: Papoutsis‐Kiachagias E. M. , Papadimitriou D. I. , Giannakoglou K. C.
Published: June 2011

In this paper, the second‐order second moment approach, coupled with an adjoint‐based steepest descent algorithm, for the solution of the so‐called robust design problem in aerodynamics is proposed. Because the objective function for the robust design problem comprises first‐order and second‐order sensitivity derivatives with respect to the environmental parameters, the application of a gradient‐based method , which requires the sensitivities of this function with respect to the design variables, calls for the computation of third‐order mixed derivatives. To compute these derivatives with the minimum CPU cost, a combination of the direct differentiation and the discrete adjoint variable method is proposed. This is presented for the first time in the relevant literature and is the most efficient among other possible schemes on condition that the design variables are much more than the environmental ones; this is definitely true in most engineering design problems. The proposed approach was used for the robust design of a duct, assuming a quasi‐1D flow model; the coordinates of the Bézier control points parameterizing the duct shape are used as design variables, whereas the outlet Mach number and the Darcy–Weisbach friction coefficient are used as environmental ones. The extension to 2D and 3D flow problems, after developing the corresponding direct differentiation and adjoint variable methods and software, is straightforward. Copyright © 2011 John Wiley & Sons, Ltd.
Channel movement and erosion response to rainfall variability in southeast Australia
Authors: Hancock G. R. , Coulthard T. J.
Published: June 2011

Intrinsic and extrinsic forces on the catchment and stream channel network drive morphological change. Separating individual forcings is difficult given the complexity of such nonlinear systems. Here a modelling approach is used to investigate the sensitivity of channel position and movement under a series of realistic rainfall scenarios for a catchment in southeastern Australia. The results demonstrate the sensitivity of the catchment to different rainfall patterns and how relatively small changes in rainfall can lead to much larger sediment outputs revealing sensitivity to subtle changes in climate. Channel movement occurs as an avulsion. This is the first time such a process has been observed and modelled in an ephemeral stream environment and demonstrates fluvial geomorphic change at human time scales. Human intervention by rock lining channels was demonstrated to prevent the movement of the main channel. Overall the CAESAR landscape evolution and erosion model used in this study is able to replicate both erosion rates and the variation in past channel movement. The modelling suggests that any landscape change is based on both internal and external forcing and that landscape history also plays a significant role. Here, we demonstrate the potential to quantify many of the nonlinearities and thresholds in soil‐mantled catchments using a landscape evolution model. Copyright © 2011 John Wiley & Sons, Ltd.
Changes and challenges in 20 years of research into the development of executive functions
Authors: Hughes Claire
Published: June 2011

This review of 20 years of developmental research on Executive Functions (EF) offers a broad‐brushstroke picture that touches on multiple issues including: (i) findings from typical and atypical groups, from infancy to adolescence; (ii) advances in assessment tools and in statistical analysis; (iii) the interplay between EF and other cognitive systems (e.g. those involved in children's developing understanding of mind, and in their processing of reward signals); (iv) integration of cognitive and neuroscience perspectives on EF; and (v) environmental factors that have either a positive influence (e.g. training/intervention programmes; parental scaffolding) or a negative influence (e.g. maltreatment, neglect, traumatic brain injury) on EF. Of the several themes to emerge from this review, two are particularly important; these concern the need to adopt developmental perspectives and the potential importance for intervention work of research on social influences on EF. Specifically, the review highlights both developmental continuities (e.g. in the correlates of EF) and contrasts (e.g. in the nature of EF and its neural substrates) and calls for research that compares developmental trajectories for EF in different groups (e.g. children with autism versus ADHD). In addition, findings from both family‐based research and randomized controlled trials of school‐based interventions highlight the importance of environmental influences on EF and so support the development of interventions to promote EF and hence improve children's academic and social outcomes. Copyright © 2011 John Wiley & Sons, Ltd.
Water order profiles on phospholipid/cholesterol membrane bilayer surfaces
Authors: Robinson David , Besley Nicholas A. , O'shea Paul , Hirst Jonathan D.
Published: June 2011

Water is pivotal in the stabilization of macromolecular biological structures, although the dynamic ensemble structure of water near to molecular surfaces has yet to be fully understood. We show, through molecular simulation and fluorescence measurements, that water at the membrane surface is substantially more ordered than bulk water, due to a loss of hydrogen bonding between water molecules, coupled with an alignment of lipid and water dipole moments. Ordering of the water leads to a gradient in the effective dielectric permittivity, which is evident in both the molecular simulations and the fluorescence measurements. A lower effective dielectric permittivity was correlated with a decreasing degree of hydrogen bonding over the same spatial range. The water molecules closest to the lipid headgroup oxygen atoms form hydrogen bonds which exhibit a mean lifetime of 6.3 ps, compared with a mean lifetime of water‐water hydrogen bonds of less than 2 ps. Membranes made up purely of phosphatidylcholine (PC) were compared with those made with a PC/cholesterol ratio relevant to cell membranes. Clear differences were found between these membrane configurations. These observations point to molecular structural differences in the surface environments of membranes and may underlie regional differences in the surface biophysical properties of membrane microdomains. © 2011 Wiley Periodicals, Inc. J Comput Chem, 2011.
The influence of cerium ion concentrations on the characteristics of hybrid films obtained on AA2024‐T3 aluminum alloy
Authors: Malfatti C. F. , Menezes T. L. , Radtke C. , Esteban J. , Ansart F. , Bonino J. P.
Published: June 2011

This work aimed to study the corrosion behavior of AA2024‐T3 aluminum alloy substrates pre‐treated with 3 glicidoxypropyltrimethoxysilane (GPTMS) silane layers doped with different cerium ion concentrations. The withdrawal speed of substrates from the sol was 20 cm · min−1. The hybrid films were obtained by dip‐coating process and analyzed by scanning electron microscopy (SEM) and energy dispersive spectroscopy, Rutherford scattering spectroscopy (RBS), salt spray test, and electrochemical analyses. The correlation among the results obtained from different analyses was very good and indicated that the addition of Ce ion in the hybrid coating contributed to the corrosion resistance; however, for the high Ce ion concentration, the barrier effect of the hybrid films was deteriorated. The results obtained by RBS showed that the concentration of Ce ion in the hybrid film increased linearly with the concentration of Ce ion in the sol. Moreover, it was verified that, for the nominal concentration of 0.05 M Ce ion in the sol, the Ce atomic fraction increased in the hybrid film, while the Si atomic fraction reduced, indicating the possible modification on the silane network due to the incorporation of Ce ions.
An embedded multi‐parameter corrosion sensor for reinforced concrete structures
Authors: Yu H. , Caseres L.
Published: June 2011

A prototype of an embedded corrosion sensor has been developed for assessing the corrosion status of reinforcing steel bar (rebar) in concrete. The integrated sensor unit includes an Ag/AgCl probe, a metallic oxide probe, a multi‐electrode array sensor (MAS), and a four‐pin (Wenner) array stainless steel electrode for chloride content, pH, microcell corrosion current, and localized concrete resistivity measurements, respectively. A stable solid probe was used as the reference probe in this unit to express the potentiometric measurement of chloride content and pH probes. In this study, the chloride and pH probes were calibrated in simulated pore solutions (SPSs) regarding temperature and pH fluctuations. The corrosion current results of the MAS probe in SPSs matched very well with those obtained by the linear polarization resistance technique, which was conducted on companion carbon steel specimens. A sensor prototype was embedded into a paste cylinder for long‐term performance evaluation. Up‐to‐date results show that the sensor probes exhibit excellent sensitivity and reliability through 1 year of monitoring. Continuous monitoring in the laboratory for extended periods is underway.